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The repellent activity of two odourless vegetable oils (sweet almond—SAO and soybean—SO) applied on filter paper and four types of food packaging materials (polyethylene film, plastic gunnysacks, cardboard, and wood) was tested against three species of stored product pests (Sitophilus granarius, Tribolium castaneum, and Oryzaephilus surinamensis). The repellence of three doses was evaluated after 24 h, and after 7, 14, 21, and 28 days. Both oils exhibited a repellent effect when applied to filter paper, but this effect decreased with time and concentration. The most susceptible species was T. castaneum. The maximum repellence was 84% and 76% for SO and SAO, respectively. On packaging materials, the repellent effect diminished after a certain period of time, ranging from 7 to 28 days. Subsequently, the oils even became attractive. Generally, the repellent effects of both SO and SAO were higher on cardboard and wood slab than on polyethylene film and plastic gunnysacks. As such, in the case of SO, the repellence against T. castaneum was 88% 24 h after application on cardboard, whilst 68% on plastic bag. This work demonstrated the repellent potential of vegetable oils in the short term for the protection of packaged food against stored product pests. [ABSTRACT FROM AUTHOR]

Pogonomyrmex badius (Florida Harvester Ant) is an ecosystem engineer that feeds on both seeds and insects. Currently, we know little about this species' collection of seeds versus insects or how consumption of these diets might change seasonally. We also know little about how competition with Solenopsis invicta (Red Imported Fire Ant) influences diet choice of Florida Harvester Ants or how it may have contributed towards the observed range decline of the native species. To investigate collection of food items by Florida Harvester Ants and the effects of competition by Red Imported Fire Ants on Florida Harvester Ant foraging, we conducted 2-choice trials of seed and insect baits at 9 different Florida Harvester Ant nests, 5 of which had been treated to eliminate Red Imported Fire Ants. Collections were assessed on 7 separate occasions from July 2020 to April 2021. The collection of seeds and insects by Florida Harvester Ants was largely similar and varied with the seasons. The highest collection rates occurred in the summer and continued into autumn. There was a noticeable decline in collection starting in late November, though this seasonal trend was significant for insect collection but not seeds. The presence of Red Imported Fire Ants decreased the collection of both seeds and insects by the Florida Harvester Ants, though for both types of food items, the difference was significant only at distances closer to their nests. [ABSTRACT FROM AUTHOR]

BACKGROUND: Odorant‐binding proteins (OBPs) in insects are key to detection and recognition of external chemical signals associated with survival. OBP7 in Spodoptera frugiperda's larval stage (SfruOBP7) may search for host plants by sensing plant volatiles, which are important sources of pest attractants and repellents. However, the atomic‐level basis of binding modes remains elusive. RESULTS: SfruOBP7 structure was constructed through homology modeling, and complex models of six plant volatiles ((E)‐2‐hexenol, α‐pinene, (Z)‐3‐hexenyl acetate, lauric acid, O‐cymene and 1‐octanol) and SfruOBP7 were obtained through molecular docking. To study the detailed interactions between the six plant volatile molecules and SfruOBP7, we conducted three 300 ns molecular dynamics simulations for each study object. The correlation coefficients between binding free energy obtained by molecular mechanics/generalized Born surface area together with solvated interaction energy methods and experimental values are 0.90 and 0.88, respectively, showing a good correlation. By comparing binding free energy along with interaction patterns between SfruOBP7 and the six volatile molecules, hotspot residues of SfruOBP7 when binding with different volatile molecules were determined. Hydrophobic interactions stemming from van der Waals interactions play a significant role in SfruOBP7 and these plant volatile systems. CONCLUSION: The optimized three‐dimensional structure of SfruOBP7 and its binding modes with six plant volatiles revealed their interactions, thus providing a means for estimating the binding energies of other plant volatiles. Our study will help to guide the rational design of effective and selective insect attractants. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background Limited research has explored the impact of mosquito repellents exposure during early life on ADHD symptoms. This study aimed to explore the associations of exposure to mosquito repellents from pregnancy to 3 years old and the prevalence of ADHD-like behaviours among children aged 3–9 years, and further identify the sensitive exposure period. Methods A cross-sectional study was conducted, including 12 275 children in Hefei City, China. Exposure was self-reported via primary caregivers. ADHD-like behaviours were measured by the Swanson, Nolan and Pelham, version IV scale (SNAP-IV), and Conners' Parent Rating Scale (CPRS). Cross-over analysis, binary logistic regression and linear regression were employed. Results After adjusting for confounding variables, early-life exposure to mosquito repellents was associated with a higher risk of ADHD-like behaviours (OR = 1.81, 95% CI = 1.49–2.19). By comparing the strength of the association for each subgroup, we found exposure during 1–3 years old was a sensitive period (OR = 1.89, 95% CI = 1.25–2.87) by the cross-over analysis. Furthermore, we found a dose–response relationship in which the likelihood of ADHD-like behaviours increased with children's early-life mosquito repellents exposure dose. Conclusions Early-life exposure to mosquito repellents is linked with an elevated risk of ADHD-like behaviours in children, with a sensitive period identified during 1–3 years old. [ABSTRACT FROM AUTHOR]

Tithonia diversifolia has the potential for use as a reservoir for entomophages in pest control, as it attracts and preserves natural enemies before migrating to the target crop, where a high incidence of pests occurs. For example, in tomato crop production one of the limiting factors, under field condition, is the incidence of phytophagous insects. We determined the effects of Tithonia diversifolia on species assemblage structure of natural enemies and pest insects (abundance and diversity), plant growth (leaf area, stem length and diameter, number of leaves, flowers and fruits, and fruits weight/per plant), plant defense (leaf thickness and hardness) and fruit colouration on tomato plants in open conditions. Through direct and indirect samplings, a total of 456 insects were collected, comprising 76 natural enemies, 269 pests and 111 belonging other guilds. Length, stem diameter, number of flowers, leaf thickness, and hardness increased, while the number of leaves decreased. T. diversifolia plants increased natural enemies but not pest abundance in tomato plants, demonstrating that this plant can alter the structure of the insect community associated with tomato. [ABSTRACT FROM AUTHOR]

The textile industry comprises technologies that transform synthetic or natural fibers into yarn, cloth, and felt for manufacturing clothing, upholstery, and household linens. The major public health threat in tropical and subtropical countries is mosquito‐borne malaria. Nowadays, the demand for insect repellent‐based textiles is continuously rising, as they are used for protection against diseases transmitted by mosquitoes. The present work reviews studies on the fabrication of insect repellent containing electrospun polymeric nanofibers as principal tools for protecting people against mosquito bites. Electrospinning technology is a remarkably facile technique for fabricating polymeric nanofiber devices. The technique is outlined and elucidated. The performance of insect repellent‐based polymeric nanofibers against mosquitoes is carefully reported and comprehensively reviewed in‐depth. Furthermore, the progress made on the mathematical modeling of the release rate of repellents through polymeric nanofiber devices is reviewed. The reviewed studies demonstrate that repellents can be released slowly from electrospun nanofibers, increasing the product's protection period against insects. The reviewed works suggest that electrospinning technology has led to an effective and facile methodology for fabricating functional nanofiber textiles with insect repellent. The reviewed studies showed that product‐based repellents can be effective not only against malaria but also against other mosquito‐borne diseases. [ABSTRACT FROM AUTHOR]

In recent years, consumer preferences have begun to turn back to natural dyes, whereas synthetic dyes have been pushed into the background over the previous 60 years. This is a result of increased knowledge of the potential hazards associated with the creation of synthetic dyes, which use raw materials derived from petrochemicals and involve intense chemical interactions. Such dyes need a lot of energy to produce, and their negative effects on the environment increase pollution. It has been discovered that several of these dyes, particularly the azo-based ones are carcinogenic. On the contrary, natural dyes are getting more attention from scientists and researchers as a result of their several advantages like being eco-friendly, biodegradable and renewable, sustainable, available in nature, having no disposal problems, minimizing the consumption of fossil fuel, anti-bacterial, insect repellent, and anti-allergic, anti-ultraviolet, intensify dyeing and finishing process efficiency, less expensive, and no adverse effects on human health and environment. However, there are also some drawbacks, like poor fastness properties, natural dye printing for bulk production, difficulties in reproducibility of shades, and so forth. Despite all these limitations, the demand for natural dyes is increasing significantly in textile industries because they offer far more safety than synthetic dyes. This study provides an overall concept of the natural dyes in textile printing. It illustrates parameters of printing performance, methods, and techniques of extraction of natural dyes, printing methods, and printing of natural and synthetic fibers. Finally, this study describes the challenges and future prospects of natural dyes in textile printing. [ABSTRACT FROM AUTHOR]

Little is known about Native American adaptations to blood-sucking arthropods prior to and following European contact. Multiple accounts starting in the 16th century suggest that rancid animal grease was employed by Gulf Coast indigenes as a mosquito repellent. Although many Native American ethnobotanical remedies for biting insects have been recorded, the use of animal products for this purpose is not well documented. Moreover, few traditional Native American mosquito repellents have been examined using controlled laboratory methods for repellency testing. In this study, we tested the repellent efficacy of fats derived from alligator, bear, cod, and shark that were aged to various stages of rancidity. Using yellow fever mosquitoes, (Aedes aegypti), we performed an arm-in-cage assay to measure the complete protection times resulted from these fats, when applied to human skin. We used a Y-tube olfactometer assay to evaluate long-distance repellency and tested tick-repellency in a crawling assay. Our results suggest that rancid animal fats from cod, bear, and alligator are potent albeit short-lived mosquito repellents. We found that both rancid and fresh fats do not repel ticks. Our findings show the validity of traditional ethnozoological knowledge of Native American people and support aspects of the ethnohistorical record. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) are natural products currently used to control arthropods, and their interaction with insect odorant-binding proteins (OBPs) is fundamental for the discovery of new repellents. This in silico study aimed to predict the potential of EO components to interact with odorant proteins. A total of 684 EO components from PubChem were docked against 23 odorant binding proteins from Protein Data Bank using AutoDock Vina. The ligands and proteins were optimized using Gaussian 09 and Sybyl-X 2.0, respectively. The nature of the protein-ligand interactions was characterized using LigandScout 4.0, and visualization of the binding mode in selected complexes was carried out by Pymol. Additionally, complexes with the best binding energy in molecular docking were subjected to 500 ns molecular dynamics simulations using Gromacs. The best binding affinity values were obtained for the 1DQE-ferutidine (−11 kcal/mol) and 2WCH-kaurene (−11.2 kcal/mol) complexes. Both are natural ligands that dock onto those proteins at the same binding site as DEET, a well-known insect repellent. This study identifies kaurene and ferutidine as possible candidates for natural insect repellents, offering a potential alternative to synthetic chemicals like DEET. [ABSTRACT FROM AUTHOR]

Cuelure, an effective lure specifically targeting Tephritid fruit flies, has been widely adopted and applied in the monitoring and control of these pests, providing significant support for agricultural pest management. However, its uncontrollable release speed and duration usually lead to a lot of waste, diminishing its effectiveness and increasing the cost of pest control. In order to solve these problems, we focused on Zeugodacus cucurbitae Coquillett and developed a temperature-sensitive nano-controlled release agent for cuelure. The release rate of this agent can be adjusted by adjusting the ambient temperature. The results show that the temperature-sensitive cuelure nano-controlled release agent demonstrates remarkable temperature-responsive controlled release characteristics. It still exhibits exceptional stability even after being subjected to high-temperature treatment at 60 °C for a week, and the trapping efficiency of this attractant remains between 73% and 75%. This study not only holds immense practical value in monitoring, warning, and managing of fruit fly pests, but it also lays a novel theoretical foundation for the development of insect attractants. [ABSTRACT FROM AUTHOR]

Objectives: In Pakistan, cutaneous leishmaniasis is an emerging tropical disease and a very high number (>70%) of children are afflicted by this marring infection. This study aimed to scrutinise the prevalence, spatial distribution and socio‐demographic and behavioural risk factors associated with cutaneous leishmaniasis in children aged <5–15 years in Khyber Pakhtunkhwa. Methods: A total of 1, 559 clinically confirmed records of children diagnosed with cutaneous leishmaniasis (January–December) from 2020 and 2022 were obtained from selected district hospitals. In addition, a risk factors‐related questionnaire was administered to 1, 011 households (400 in 2020 and 611 in 2022) in nine districts during a household survey. Results: The maximum number of cutaneous leishmaniasis cases was recorded in 2022 (n = 877, 56.25%) as compared to 2020 (n = 682, 43.75%). The hospital records showed a greater number of male patients in the 2022 cohort (n = 603, 68.76%). The highest number of cases were observed in children aged 5–9 years in 2022 (n = 282, 32.16%) and 2020 (n = 255, 37.39%). In 2020 and 2022, cutaneous leishmaniasis cases showed peak aggregation in March (n = 118, 17.3%) and January (n = 322, 36.72%). From a spatial analysis, the maximum number of cutaneous leishmaniasis cases was recorded at 59–1700 m elevation in various land‐use/land‐cover and climatic regions with quaternary alluvium rock formations. A multivariate logistic regression model analysis of risk factors from the households survey suggested that age group, socio‐economic status, construction materials of the house, use of insect repellents, Afghan refugee camps in the village/district, knowledge and biting times of sand flies, frequent use of mosquito bed nets, presence of domestic animals in the house, knowledge of the transmission period and peak month of leishmaniasis infection increased the risk of acquiring cutaneous leishmaniasis (p value < 0.05). Conclusion: Our analysis demonstrated that cutaneous leishmaniasis in children is influenced by a variety of environmental, socio‐demographic and behavioural risk factors in Khyber Pakhtunkhwa. The increase in recorded cases of cutaneous leishmaniasis in children in 2022 compared to 2020 suggests that the infection likely extended to new foci in the province. [ABSTRACT FROM AUTHOR]

Nowadays, sustainable approaches for the colouration of textiles are in high demand. Functional textiles remain a top choice for the user as they serve dual functions. The present study focuses on the utilisation of turmeric natural dye for dyeing of cotton using a novel method. A mosquitorepellent ethyl anthranilate was diazotised in the presence of sodium nitrite and hydrochloric acid. The diazotised derivative of ethyl anthranilate was reacted with turmeric-treated fabric by in-situ azoic dyeing method. The developed dyed fabric was evaluated for fastness and colour measurements. Functional effects provided by dyed fabrics (mosquito repellency and UV protection) were also assessed using standard methods. Dyed fabrics indicated excellent UV protection and 100 % mosquito repellency. The introduction of functional groups (azo and aromatic) of the developed dye in the cotton was also confirmed through FTIR analysis. A novel functional finishing-cum-dyeing approach for the functionalization of cellulosic fabrics was explored using turmeric extract and ethyl anthranilate. [ABSTRACT FROM AUTHOR]

Looper infestation in tea growing region of the sub-Himalayan range poses a severe threat to tea industries that can jeopardize a major player in the nation's economy. Despite undertaking several control measures, their impact has only grown due to climate change and ineffective pest management strategies. This comprehensive review consolidates findings from various published articles, encompassing this pest's ecology, morphology, diversity, their resistance patterns to plant allelochemicals and pesticides, and impact of climate change on the growth and development. The pest's habit and habitat, lifecycles, interactions with the environment, and defensive strategies are being studied thoroughly. This review also underscores the paradoxical issue of shade tree planting in tea plantations, which, while integral for quality tea-leaves, inadvertently fosters pest outbreaks. To address this, the planting of suitable shade trees like Melia azedarach, having insect repellent ability has been endorsed. Understanding these factors may result in low-cost maintenance, reduction in crop losses, and improved overall efficiency in pest management. This knowledge facilitates the development of proactive and sustainable pest management strategies, which effectively minimize the emergence, and proliferation of resistance, thereby safeguarding the long-term efficiency of pest management strategies. [ABSTRACT FROM AUTHOR]

SUMMARY: Iridoids are non‐canonical monoterpenoids produced by both insects and plants. An example is the cat‐attracting and insect‐repelling volatile iridoid nepetalactone, produced by Nepeta sp. (catmint) and aphids. Recently, both nepetalactone biosynthetic pathways were elucidated, showing a remarkable convergent evolution. The iridoid, dolichodial, produced by Teucrium marum (cat thyme) and multiple insect species, has highly similar properties to nepetalactone but its biosynthetic origin remains unknown. We set out to determine the genomic, enzymatic, and evolutionary basis of iridoid biosynthesis in T. marum. First, we generated a de novo chromosome‐scale genome assembly for T. marum using Oxford Nanopore Technologies long reads and proximity‐by‐ligation Hi‐C reads. The 610.3 Mb assembly spans 15 pseudomolecules with a 32.9 Mb N50 scaffold size. This enabled identification of iridoid biosynthetic genes, whose roles were verified via activity assays. Phylogenomic analysis revealed that the evolutionary history of T. marum iridoid synthase, the iridoid scaffold‐forming enzyme, is not orthologous to typical iridoid synthases but is derived from its conserved paralog. We discovered an enzymatic route from nepetalactol to diverse iridoids through the coupled activity of an iridoid oxidase cytochrome P450 and acetyltransferases, via an inferred acylated intermediate. This work provides a genomic resource for specialized metabolite research in mints and demonstration of the role of acetylation in T. marum iridoid diversity. This work will enable future biocatalytic or biosynthetic production of potent insect repellents, as well as comparative studies into iridoid biosynthesis in insects. Significance Statement: Cat thyme (Teucrium marum) produces the iridoid dolichodial which can repel certain insects and attract cats; the compound is also produced by some insect species. We generated a de novo chromosome‐scale genome assembly for T. marum, investigated the genetic and enzymatic basis of iridoid biosynthesis, and demonstrated the role of acetylation in generating iridoid diversity. [ABSTRACT FROM AUTHOR]

The research conducted so far on the chemical mechanisms of trees' defence against foliophages has not uncovered the chemical compounds biosynthesized by plants that are essential for these mechanisms. The objective of this study was to identify a chemical indicator for the presence of the pine beauty moth in Pinus sylvestris stands. Fresh needled shoots were collected from the crowns of pine trees in stands where the pine beauty moth tends to occur in large numbers, as well as from control stands. Total phenolic contents, total flavonoids contents, total chlorophyll content, terpene compounds, phenolic compound concentration, LMWOAs, sugar content, and colour analysis were conducted. Chlorophyll content, the presence of Panolis flammea in forest stands, and the colour of pine needles were discovered to be related. Variable L* correlated positively with the concentrations of chlorophyll a and b. In pine needles that were not attacked by the pine beauty moth, significantly higher concentrations of 4‐hydroxybenzoic acid, salicylic acid, chlorogenic acid, syringic acid, quercitin, and rutin were found, with the first compound having the most significant effect (4‐hydroxybenzoic acid). Based on the study results, the connected compounds in pine needles make them susceptible to insect attack. In addition, insect repellent programmes were mentioned. [ABSTRACT FROM AUTHOR]

Malaria has been, and still is, a major cause of not only human suffering and death and infant mortality, but also an economic burden on the society. According to the WHO Report of 2022, in 2021 alone 247 m people were affected by malaria. Apart from the use of antimalaria drugs, the importance of different preventive measures including the use of mosquito nets and insect repellents in managing malaria cannot be gainsaid. It should be underscored that the determined research efforts by medical personnel such as Ronald Ross, Patrick Manson, Charles Louis Alphonse Laveran, Giovanni Battista Grassi, and a few others, despite several hardships they faced in pinning the mosquito as the transmitter of malaria was epoch-making. Obviously, this finding has played a key role in reducing the global impact of malaria. In this communication, I outline the efforts of Ronald Ross and the travails he went through while pursuing it, as well as his attitude in denying his co-workers their due credit, and the extroversion rooted in him which eventually made him turn hostile to his collaborators and to his mentor, Patrick Manson. [ABSTRACT FROM AUTHOR]

Microcapsules loaded with essential oils, namely Litsea cubeba, Cymbopogon nardus and Cymbopogon citratus, in gum arabic and chitosan were prepared to explore their mosquito repelling effects and their antimicrobial function. The encapsulation ratio, along with the materials characterization and release behavior of the essential oils from the microcapsules were studied, together with temperature and time dependences. Mosquito repellency was assessed against Ae. aegypti using the "arm-in-cage" method, and the antibacterial activity was tested against E. coli and S. aureus. The results demonstrated that microcapsules loaded with essential oils were successfully prepared for all three essential oils. Also, the results showed that the highest encapsulation ratio was found for microcapsules loaded with Cymbopogon citratus oil. The microcapsules loaded with all essential oils were effective in prolonging protection time against Ae. aegypti, especially in the case of the Litsea cubeba oil, while the Cymbopogon nardus and Cymbopogon citratus oils yielded the highest antibacterial activity against E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

Batocera horsfieldi (Hope) (Coleoptera: Cerambycidae) is an important pole borer pest. It causes serious harm to various hosts, particularly Juglans regia L. (Juglandaceae). In this study, headspace solid‐phase microextraction (HS‐SPME), gas chromatography–mass spectrometry (GC–MS), and electroantennogram (EAG) responses were combined to examine the mechanism by which B. horsfieldi adults locate their host, J. regia. The results showed that J. regia contained 65 volatile compounds in all, with 36 and 42 volatile substances in bark and leaves, respectively. Moreover, terpenes accounted for the largest relative content among the volatile compounds of bark and leaves, 43.4 and 78.9%, respectively. Ten of 19 selected volatile components elicited significant EAG responses in adult B. horsfieldi, which indicated that the pest may prefer certain volatile compounds when selecting a host. Sex and volatile concentration affected the responses of B. horsfieldi. Male adults had the strongest EAG responses to 1‐octen‐3‐ol, whereas female adults had the strongest EAG responses to linalool. Host selection in B. horsfieldi was somewhat positively associated with the concentrations of the effective volatile compounds in the host. Furthermore, B. horsfieldi showed varying preferences for isomers. This work provided data support for the development of insect attractants, and laid a theoretical foundation for the ecological protection of local forestry. [ABSTRACT FROM AUTHOR]

Catnip (Nepeta cataria L.) plants produce a wide array of specialized metabolites with multiple applications for human health. The productivity of such metabolites, including nepetalactones, and natural insect repellents is influenced by the conditions under which the plants are cultivated. In this study, we assessed how field-grown catnip plants, transplanted after being propagated via either single-node stem cuttings or seeds, varied regarding their phytochemical composition throughout a growing season in two distinct environmental conditions (Pittstown and Upper Deerfield) in the state of New Jersey, United States. Iridoid terpenes were quantified in plant tissues via ultra-high-performance liquid chromatography with triple quadrupole mass spectrometry (UHPLC-QqQ-MS), and phenolic compounds (phenolic acids and flavonoids) were analyzed via UHPLC with diode-array detection (UHPLC-DAD). The highest contents of total nepetalactones in Pittstown were found at 6 weeks after transplanting (WAT) for both seedlings and cuttings (1305.4 and 1223.3 mg/100 g, respectively), while in Upper Deerfield, the highest contents for both propagules were at 11 WAT (1247.7 and 997.1 mg/100 g, respectively) for seed-propagated and stem cuttings). The highest concentration of nepetalactones was associated with floral-bud to partial-flowering stages. Because plants in Pittstown accumulated considerably more biomass than plants grown in Upper Deerfield, the difference in nepetalactone production per plant was striking, with peak productivity reaching only 598.9 mg per plant in Upper Deerfield and 1833.1 mg per plant in Pittstown. Phenolic acids accumulated in higher contents towards the end of the season in both locations, after a period of low precipitation, and flavone glycosides had similar accumulation patterns to nepetalactones. In both locations, rooted stem cuttings reached their maximum nepetalactone productivity, on average, four weeks later than seed-propagated plants, suggesting that seedlings have, overall, better agronomic performance. [ABSTRACT FROM AUTHOR]

N, N‐diethyl‐meta‐toluamide (DEET) has been considered the 'gold standard' for insect repellent use since the 1950s and constitutes most insect repellents on the market. However, conflicting data in the scientific literature and confusing information in the media are at the core of debates about the safety of DEET insect repellents for the protection of children against arthropod bites. The few fatal occurrences involving DEET insect repellents and complications of their use in the pediatric population are typically the result of accidental overdoses or misuse of insect repellents that disregard warnings on product labels. With appropriate application, the safety record of DEET insect repellents continues to be excellent with few side effects. The purpose of this review is to provide a summary of the literature on safety outcomes of DEET insect repellent use in children; outline the pediatric recommendations relating to DEET insect repellents; and provide an overview of EPA‐approved and naturally derived alternatives to DEET that possess low toxicity while providing a similar level of protection to synthetic insect repellents. [ABSTRACT FROM AUTHOR]

Birds must cope with all manner of ectoparasites, from insects and mites to bacteria and fungi. During their grooming routine, several Norfolk Island green parrots Cyanoramphus cookii were observed and photographed, and a pair was videoed, biting off and chewing small pieces of lateral shoot and bark of pepper trees Piper excelsum and working the chewed material through their feathers. They also stripped the leaves and rubbed their beaks along the branches before extracting preen oil. Pepper trees are a well‐known source of piperine and other potent aromatic chemicals that are insect repellent and antimicrobial. This appears to be a rare example of a bird using plant material to anoint themselves, which we interpret as a way to repel blood‐sucking insects and ectoparasites and, possibly, void endoparasites, thereby improving fitness. [ABSTRACT FROM AUTHOR]

In the mobility market, there is a demand from customers for antimicrobial protection. As a result, the market has grown considerably to provide antiviral and antimicrobial polymers and coatings. This study examines how the efficacy of a non‐commercial antimicrobial thermoplastic elastomer will change over the life of the application. Using an example application of an electric scooter handlebar grip, durability requirements were identified, and antiviral efficacy (exceeding a log value of 3 or >99.9 microbial growth reduction) was compared before and after testing. A scooter handlebar grip was selected as the ideal example application as it was a high‐touch surface, with several different riders. During the start of this study, scooter companies were encouraging their riders to disinfect scooter handlebars before riding, use hand sanitizer, and wear gloves. If the handlebar grip could be antimicrobial, then they could eliminate these steps and provide a safe ride for the users. In order to simulate long‐term durability, UV exposure, temperature, humidity, artificial sweat, sunscreen, insect repellent, and abrasion tests were performed and evaluated in terms of antiviral activity. Accelerated weathering reduced the virucidal activity of the sample versus unexposed antiviral thermoplastic elastomer (TPE). However, the efficacy increased with contact time from 90% to 96.83% at 30 and 120 min, respectively. Abrasion resistance of antiviral TPE showed a volume loss of 66 mm3 compared to control samples of 83 mm3. The antiviral TPE sample exhibited slightly lower efficacy compared to the control after exposure to the artificial sweat (99.43% vs. 99.95%). Additionally, a skin tolerance test conducted on rabbits showed that antiviral TPE was not an irritant and showed no dermal toxicity. The outcome of this study will lead to the development of long‐term durable antimicrobial material for the transportation industry. Highlights: The effectiveness of an antimicrobial material depends on various environmental factors.Accelerated weathering of the antiviral TPE reduced the efficacy.The antiviral TPE was non‐irritating to the skin.Significant research needs to continue in this area to provide safe and robust solutions.This approach to antimicrobial incorporation can now be applied to the transportation industry. [ABSTRACT FROM AUTHOR]

Background: The wasabi receptor, also known as the Transient Receptor Potential Ankyrin 1 (TRPA1) ion channel, is a potential target for development of repellents for insects, like the pine weevil (Hylobius abietis) feeding on conifer seedlings and causing damage in forestry. Heterologous expression of TRPA1 from pine weevil in the yeast Pichia pastoris can potentially provide protein for structural and functional studies. Here we take advantage of the Green Fluorescent Protein (GFP) tag to examine the various steps of heterologous expression, to get more insight in clone selection, expression and isolation of the intact purified protein. Results: The sequence of HaTRPA1 is reported and GFP-tagged constructs were made of the full-length protein and a truncated version (Δ1-708 HaTRPA1), lacking the N-terminal ankyrin repeat domain. Clones were screened on GFP expression plates, induced in small liquid cultures and in fed-batch cultures, and evaluated by flow cytometry and fluorescence microscopy. The screening on plates successfully identifies low-expression clones, but fails to predict the ranking of the best performing clones in small-scale liquid cultures. The two constructs differ in their cellular localization. Δ1-708 HaTRPA1 is found in a ring at the perimeter of cell, whereas HaTRPA1 is forming highly fluorescent speckles in interior regions of the cell. The pattern is consistent in different clones of the same construct and persists in fed-batch culture. The expression of Δ1-708 HaTRPA1 decreases the viability more than HaTRPA1, and in fed-batch culture it is clear that intact cells first express Δ1-708 HaTRPA1 and then become damaged. Purifications show that both constructs suffer from degradation of the expressed protein, but especially the HaTRPA1 construct. Conclusions: The GFP tag makes it possible to follow expression by flow cytometry and fluorescence microscopy. Analyses of localization, cell viability and expression show that the former two parameters are specific for each of the two evaluated constructs, whereas the relative expression of the constructs varies with the cultivation method. High expression is not all that matters, so taking damaged cells into account, something that may be linked to protein degradation, is important when picking the most suitable construct, clone, and expression scheme. [ABSTRACT FROM AUTHOR]

Extrafloral nectaried plants and myrmecophytes offer resources to ants that engage in protective mutualisms. The role of different ant species in herbivore deterrence has long been analyzed by using insect baits, and ants are regarded as effective plant guards if they attack the insects. Here, by performing a literature review, we conducted a comparative investigation on which ants display aggression toward experimental prey, which ants are better plant guards, and which plants (extrafloral nectaried plants or myrmecophytes) are better defended by ants. Data revealed that studies evaluating ant aggression toward insect baits have been performed on 37 extrafloral nectaried plant species and 19 myrmecophytes, and have involved over 30 genera of ants. Extrafloral nectaried plants and myrmecophytes rely on specific ant fauna to defend them from herbivores. In extrafloral nectaried plants, Camponotus and Crematogaster were regarded as the best plant protectors, as they attacked insects in nearly all plants. In myrmecophytes, Azteca, Pheidole, and Pseudomyrmex were the most important insect attackers. Myrmecophytes were better protected by ants, as all insects were attacked; in extrafloral nectaried plants, some ants failed to attack the insects. Plants are patrolled by several different ants, but there is a core of ants that excel in protection, and this varies according to plant type (extrafloral nectaried plants and myrmecophytes). With this knowledge, it may be possible to label different ants as effective plant guards, to anticipate their effects on plant performance, and even to understand their potential role as biological control agents. [ABSTRACT FROM AUTHOR]

Malaria control efforts through vector control strategies are hindered by the development of insecticide resistance by major malaria vectors in many malaria-endemic areas, which necessitate the need for alternative control measures. The aim of this study was to document plants traditionally used as mosquito repellents in Seweyna district, southeastern Ethiopia. The ethnobotanical data were collected using semistructured interviews, field observation, and guided field walks in four kebeles of the district with 98 informants. A total of 19 plant species were used by the local community as mosquito repellent, with 42.1% being trees. These plant species belong to 12 families. Of these families, the family Burseraceae was the most represented, with four species, followed by Fabaceae (3 species). The most frequently mentioned plant species were Mimusops kummel (90.81%), followed by Acokanthera schimperi (84.69%), Boswellia microphylla (79.6%), and Calpurnia aurea (79.6%). The stem was the most common plant part used (47.3%) to repel mosquitoes. Most of the local communities (52.6%) use the burning of either fresh or dry plant parts to generate smoke, which is the most common practice. The current ethnobotanical study indicates that the local community in the Seweyna district uses the plants to repel mosquitoes. In the future, the repellent efficacy of these plants against the major malaria vector should be tested under laboratory and field conditions. Besides, the identification of the bioactive compounds responsible for the repellent activity should also be determined. [ABSTRACT FROM AUTHOR]

Death is a multifaceted process wherein each individual cell and tissue has a metabolic homeostasis and a time of functional cessation defined by the dying process as well as by intrinsic and extrinsic factors. Decomposition is physiologically associated with the release of different types of volatile organic compounds (VOCs), and these form volaboloma mortis. The main purpose of this study was to record the volabolomic fingerprint produced by volatile molecules during the physiological decomposition process of human tissue and muscle cells. The volatile chemical signature has important implications for an open issue in forensics and pathology, namely the estimation of the postmortem interval (PMI), which decreases in accuracy with the passage of time. Volatile metabolites emitted from human tissues and muscle cells at 0, 24, 48, and 72 h were recorded in real time with an electronic nose sensor device. The key findings were the continuous sampling of VOCs emitted from tissues and cells. These showed a common behavior as time progressed; particularly, after 48 h the distributions became dispersed, and after 72 h they became more variable. Volabolomic fingerprinting associated with time progression relevant to the study of PMIs was reconstructed. Additionally, there may be broader applications, such as in dog training procedures for detecting human remains, and perhaps even for studying scavenger and insect attractants. [ABSTRACT FROM AUTHOR]

Chamaecyparis obtusa (Siebold & Zucc.) Endl., which belongs to the Cupressaceae family, occurs naturally in North America and Asia, especially in Korea, Taiwan and Japan, where it is an evergreen, coniferous, sacred, ethnic tree. It has many useful varieties that are widespread throughout the world and grown for decorative purposes. It is most commonly used as an ornamental plant in homes, gardens or parks. It is also widely used in many areas of the economy; for example, its wood is used in architecture as well as furniture production. In addition, oil extracted from Chamaecyparis obtusa is increasingly used in cosmetology for skin care. Due to its wide economic demand, mainly in Japan, it represents the largest area of plantation forest. Despite this, it is on the red list of endangered species. Its use in ethnopharmacology has led to more and more research in recent years in an attempt to elucidate the potential mechanisms of its various biological activities, such as antimicrobial, antioxidant, anticancer, antidiabetic, antiasthmatic, anti-inflammatory, antiallergic, analgesic and central nervous system effects. It has also been shown that Chamaecyparis obtusa can be used as an insect repellent and an ingredient in plant disease treatment. This thesis provides a comprehensive review of the biological studies to date, looking at different areas of the economic fields of potential use of Chamaecyparis obtusa. [ABSTRACT FROM AUTHOR]

N,N-Diethyl-3-toluamide (DEET) is a commonly used insect repellent, which acts as an organic chemical contaminant in water and considered as an emerging contaminant which has been observed worldwide. It gets discharged into the environment through sewage waste. The various methods have been used to degrade DEET, such as UV based, ozonation, photocatalytic degradation, and biodegradation (based on the metabolic activity of fungi and bacteria). However, less research has been done on the degradation of DEET by deploying nanoparticles. Therefore, biodegradation and nanotechnology-based methods can be the potential solution to remediate DEET from the environment. This review is an attempt to analyze the routes of entry of DEET into the atmosphere and its environmental health consequences and to explore physical, chemical, and biological methods of degradation. Furthermore, it focuses on the various methods used for the biodegradation of the DEET, including their environmental consequences. Future research is needed with the application of biological methods for the degradation of DEET. Metabolic pathway for biodegradation was explored for the new potent microbial strains by the application of physical, chemical, and microbial genomics; molecular biology; genetic engineering; and genome sequencing methods. [ABSTRACT FROM AUTHOR]

Before the invasion of the fall armyworm (FAW) Spodoptera frugiperda into Africa, smallholder farmers had been using indigenous practices such as applying fish soup to plants to manage stemborer pests. Although farmers have since begun adapting this practice against FAW, no attempt has been made to scientifically evaluate this practice. Therefore, we assessed the efficacy of applying fish soup to maize plants that were artificially infested with FAW under semi-field conditions. Our results showed that foliar damage is inversely correlated with the concentration of a fish soup and sugar solution, with the highest (100%) concentration resulting in the lowest foliar damage and the highest plant recovery. The FAW foliar damage results for maize plants treated with 100%, 50%, 10% fish soup and sugar, and distilled water were 46.3 ± 5.6, 51.1 ± 5.0, 71.6 ± 5.2, and 99.4 ± 0.4%, respectively, whereas plant recovery results from the same treatments were 35.2 ± 3.7, 31.1 ± 5.4, 20.0 ± 4.6, and 0.0 ± 0.0%, respectively. A concentration of fish soup and sugar solution of at least 25.9% was required to achieve the lowest foliar damage of 17.8% and peak plant recovery of 73.6%. Fish soup and sugar solutions attracted a wide range of insects, including potential natural enemies (predators and parasitoids) of FAW, in a dose-dependent manner. Maize plants treated with fish soup and sugar showed higher chlorophyll content and better growth than the control did. Proximate and chemical analysis showed that fish soup contains essential plant growth nutrients (e.g., nitrogen, phosphorus, and calcium). Through GC-MS analyses, we identified 76 volatile organic compounds in fish soup, of which 16 have been reported as insect attractants, highlighting their potential ecological significance. Therefore, the indigenous pest management practices for FAW, such as the use of fish soup, deserve particular attention. These practices could contribute to food security and improve the livelihoods of vulnerable communities. Further field validation studies, economic analyses, product development, and optimisation are therefore required to optimise the use of fish soup based on fish waste. [ABSTRACT FROM AUTHOR]

The push–pull approach using semiochemicals in pest control requires both an attractant and a repellent. Many previous studies have arbitrarily tested one or more known insect repellents or plant essential oils (EOs) hoping to find repellents of an insect pest. We used a comprehensive approach that synergistically tests in the field numerous natural volatiles from commercial EOs to identify repellents of the red palm weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae), a worldwide pest of palms and date palms. Volatiles from 79 EOs in slow-release devices were divided into five groups and tested in traps with attractive pheromone compared to traps with pheromone alone. EO-treatment groups exhibiting repellency due to significant trap shutdown, were further subdivided into subgroups of four EOs each and tested further. Two groups of four EOs (cypress, desert wormwood, elemi, and Eucalyptus citriodora) and (niaouli, nutmeg, oregano, and orange sweet), or their corresponding mixtures of major volatiles, caused pheromone trap reductions of up to 92%. Further tests showed that seven of the eight EOs are similarly repellent as the corresponding subgroup. This systematic approach of successively testing sub-fractions of EOs in the field for trap shutdown should be useful to identify repellents of other insect pests of crops. [ABSTRACT FROM AUTHOR]

Gulf War illness (GWI) is a chronic multisymptom disorder of unknown etiology that is believed to be caused by neurotoxicant exposure experienced during deployment to the Gulf War. Posttraumatic stress disorder (PTSD) covaries with GWI and is believed to play a role in GWI symptoms. The present study examined the association between self‐reported military exposures and GWI, stratified by PTSD status, in veterans from the Gulf War Era Cohort and Biorepository who were deployed to the Persian Gulf during the war. Participants self‐reported current GWI and PTSD symptoms as well as military exposures (e.g., pyridostigmine [PB] pills, pesticides/insecticides, combat, chemical attacks, and oil well fires) experienced during the Gulf War. Deployed veterans' (N = 921) GWI status was ascertained using the Centers for Disease Control and Prevention definition. Individuals who met the GWI criteria were stratified by PTSD status, yielding three groups: GWI‐, GWI+/PTSD‐, and GWI+/PTSD+. Multivariable logistic regression, adjusted for covariates, was used to examine associations between GWI/PTSD groups and military exposures. Apart from insect bait use, the GWI+/PTSD+ group had higher odds of reporting military exposures than the GWI+/PTSD‐ group, adjusted odds ratio (aOR) = 2.15, 95% CI [1.30, 3.56]–aOR = 6.91, 95% CI [3.39, 14.08]. Except for PB pills, the GWI+/PTSD‐ group had a higher likelihood of reporting military exposures than the GWI‐ group, aOR = 2.03, 95% CI [1.26, 3.26]–aOR = 4.01, 95% CI [1.57, 10.25]. These findings are consistent with roles for both PTSD and military exposures in the etiology of GWI. [ABSTRACT FROM AUTHOR]

Geijera Schott is a plant genus of the Rutaceae Juss. (rue and citrus) family, comprising six species which are all native to Oceania. Of the plants belonging to this genus, the most significant species that has a customary use is Geijera parviflora, which was used by Indigenous Australians, primarily as a pain reliever. Herein, a comprehensive review of the literature published on the genus Geijera from 1930 to 2023 was conducted. This is the first review for this plant genus, and it highlights the chemical constituents reported to date, together with the range of pharmacological properties described from the various species and different parts of the plant. These properties include anti-inflammatory, anti-microbial, anti-parasitic, insect repellent, analgesic, neuroactive, and anti-cancer activities. Finally, a reflection on some of the important areas for future focused studies of this plant genus is provided. [ABSTRACT FROM AUTHOR]

This study aimed to develop a waterborne stain (WBS) that protects against weathering and increases resistance of wood to fungi when exposed to heavy rainfall. The WBS was prepared using an antibacterial agent, insect repellent, and copper nanoparticle solution (CN) as a surface coating agent. The WBS was applied on larch and hemlock wood, and changes in color and wettability due to natural and artificial weathering were evaluated. A gray-blue spot developed on the untreated wood surface within 30 d of outdoor exposure, which then spread over the entire wood surface, and the wood eventually turned black. Resistance to fungi increased when CN alone was applied; however, the CN surface was oxidized and turned gray after 30 d and 90 d for larch and hemlock, respectively. The water contact angle was increased due to leaching. The application of CN followed by WBS prevented wood discoloration under ultraviolet light and the wood showed excellent weathering resistance capacity. The prevention of wood discoloration and resistance to fungi by CN were confirmed, which could guide the development of a paint that can prolong protection from weathering of wood exposed to heavy rainfall events. [ABSTRACT FROM AUTHOR]

Azadirachta indica A. Juss (Neem) is a tree native to India that, due to its multiple properties, is currently widely distributed throughout the world, mainly in tropical and semi-arid areas, being able to withstand adverse conditions such as high temperatures and soils. arid, infertile, stony or acid. Insect repellents and insecticides, fungicides and fertilizers of extraordinary value for integrated or organic agriculture are made from this plant. The objective of this research is the determination of quality parameters of the physical-chemical variables of the oil from the seeds of Azadirachta indica A. Juss (Neem). The oil was extracted, by artisanal cold pressing, from the seeds of fruits collected from specimens cultivated in the San Antonio del Sur municipality of the Guantánamo province. The quality parameters were determined: density, acidity index, pH, refractive, iodine and saponification indices. The values of the oil quality parameters of the neem seeds were shown to be similar to the results of other researchers and to be within the ranges required by the Codex. Of all the parameters, the only one that is above the required values is the acidity index. The Neem oil from trees located in Guantánamo could be an alternative to replace imported vegetable oils for industrial use, although with previous refining processes. [ABSTRACT FROM AUTHOR]

Malaria is a disease affecting millions of people, especially in Africa, Asia, and South America, and has become a substantial economic burden. Because malaria is contracted through the bite of a mosquito vector, it is very challenging to prevent. Bed nets and insect repellents are used in some homes; others do not have or use them even when available. Thus, treatment measures are crucial to controlling this disease. Artemisinin-based combination therapy (ACT) is currently the first-line treatment for malaria. ACT has been used for decades, but recently, there has been evidence of potential resistance. This threat of resistance has led to the search for possible alternatives to ACT. In sub-Saharan Africa, Azadirachta indica, or simply neem, is a plant used to treat a variety of ailments, including malaria. Neem is effective against one of the more deadly malaria parasites Plasmodium falciparum. Reports show that neem inhibits microgametogenesis of P. falciparum and interferes with the parasite's ookinete development. Although there is substantial in vitro research on the biological activity of A. indica (neem), there is limited in vivo research. Herein, we discuss the in vivo effects of neem on malaria parasites. With A. indica, the future of malaria treatment is promising, especially for high-risk patients, but further research and clinical trials are required to confirm its biological activity. [ABSTRACT FROM AUTHOR]

The encapsulation of botanical compounds (such as citronellal) can be used to increase their efficiency and stability for functionalizing textile materials. In this study, the citronellal nanocapsules (CNC) with citronella oil as the core material and isophorone diisocyanate (IPDI) as the shell material were prepared and characterized. Factors, including core-to-shell ratio, single-phase ratios, emulsification time, as well as polymerization time and temperature, were investigated to determine the optimal process for the preparation of CNC. The average particle size of the prepared CNC was about several hundred nanometers, with uniform particle size distribution. Further, composite Lyocell fibers were prepared by the wet spinning process of co-blending CNC with Lyocell spinning stock. Evaluations were made of the biological activity of CNC towards mosquitoes, as well as E. coli and S. aureus, showing excellent mosquito repelling rate, of more than 90%, and an inhibition rate of 97.72% towards S. aureus. [ABSTRACT FROM AUTHOR]

Hyptis suaveolens (H. suaveolens), known as Gros baume or sweet-smelling Hyptis, is an invasive plant from tropical regions widely used to manage human and animal ailments, such as bacterial, viral, and parasitic diseases. This study aimed to synthesize scientific research works on the use of this medicinal plant in the traditional pharmacopeia, as well as the biological and pharmacological activities already recognized in the literature. Information for this synthesis was collected from physical (libraries and documentation centers of universities in Benin) and reliable scientific databases, such as PubMed, Google Scholar, Scopus, and Web of Science, which were queried based on the keywords related to H. suaveolens. This plant contains secondary metabolites in its aerial parts, such as leaves, and stems, which are rich in essential oils. From leaves to roots, all parts of this plant are of interest to both humans and animals to treat various pathologies. The most frequently cited diseases include asthma, panariasis, jaundice, hyperthermia, indigestion, stomach pains, nausea, colds, gall bladder infections, breast abscesses, hemorrhoids, oral-anal candidiasis, edemas, cramps, and skin infections. The various aqueous and ethanolic extracts are evaluated by researchers and the biological activities are indicated in the literature. Those activities include the antibacterial, antifungal, larvicidal, antioxidant, anticholinesterase, insect repellent, and insecticidal effects. However, no toxicity resulting from the use of this plant has yet been reported in the literature. Research on H. suaveolens toxicity must be continued to gain a comprehensive understanding of its application in human and livestock health. This literature review allows the virtues and risks related to the traditional use of H. suaveolens in human and animal pharmacopeia. The various potentialities of this plant provide a lever for exploring its antiviral effects in traditional veterinary medicine in general. [ABSTRACT FROM AUTHOR]

Introduction: In Indonesia, the average dengue cases are 121,191 each year with a Case Fatality Rate (CFR) of 0.69%. Mosquito control with common chemical methods will negatively impact the environment and human health and can cause mosquitoes to develop resistance. Environmentally-friendly replacement chemicals derived from plants such as citronella contains 16.27% citronella and 19.88% geraniol. In addition, lavender plants also contain 35% alcohol comprising linalool and geraniol as well as other chemicals such as borneol. Furthermore, 8-20% of camphor and borneol in rosemary can also be a natural mosquito repellent ingredient. Methods: This study is a True Experiment with The Posttest-Only Controlled Group Design. The number of Aedes aegypti mosquitoes used for each treatment was 20. The study subjects were divided into 4 groups comprising 0.4 ppm of citronella, lavender, and rosemary essential oils and aquades as control. Replication was carried out 3 times and observations were conducted for 20 minutes. Results and Discussion: The Anova Factorial test resulted in a p-value of ≤ 0.05. In addition, there was a significant difference in the number of Aedes aegypti mosquitoes expelled from humidifier vapor. Furthermore, the Least Significant Difference (LSD) test showed that citronella essential oil was most effective in repelling mosquitoes because it has a p-value of ≤ 0.05 and largest average difference between other essential oils. Conclusion: Essential oils from citronella are most effective and stable for 30 seconds to 20 minutes to repel mosquitoes compared to lavender and rosemary essential oils. [ABSTRACT FROM AUTHOR]

Amblyomma sculptum is a species of public health interest because it is associated with the transmission of the bacteria that causes Brazilian Spotted Fever (BSF). The use of repellents on humans is a prophylactic measure widely used to provide protection against a series of arthropod vectors, including mosquitoes and ticks. However, in Brazil, the effectiveness of commercial repellents against A. sculptum is little known. Therefore, it is necessary to carry out specific studies to evaluate the repellency of these commercial products, registered for use against mosquitoes, against the star tick. The main goal of the present work was to evaluate the effectiveness of six commercial repellents against A. sculptum. Unfed nymphs, aged between two and eight weeks, were tested against products based on DEET (OFF!® and Repelex®), Icaridin (Exposis® and SBP®), and IR3535 (Johnsons and Henlau). Three bioassays were conducted to evaluate tick behavior: (i) filter paper, (ii) fingertip, and (iii) field. All bases tested showed high repellent activity, differing significantly (p < 0.05) from the control. It was observed the formulation with DEET resulted in the best results in the filter paper bioassay. In the fingertip bioassay, the DEET base repelled a greater number of ticks compared to Icaridin. In the field bioassay, there was no significant difference between the Icaridin base and DEET, and both formulations differed from the control (p < 0.05). The six formulations tested showed significant percentages of repellency against ticks; however, for the fingertip and field bioassays, the products OFF!®, Repelex®, and Exposis® were tested as they showed better performance in the filter paper test. OFF!® showed the best percentage of repellency (100%), followed by Repelex® (96.8%), and Exposis® (93.1%), considering the two-hour period of the bioassay-field-test. Proving the effectiveness of repellents on the market against A. sculptum presented in this study is crucial, since this is the main ectoparasite of humans that can transmit Rickettsia rickettsii when infected. The effectiveness of commercial insect repellents against other tick species that parasitize humans can also be explored. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is an important olfactory cue in Drosophila melanogaster and can elicit both attractive and aversive behaviors. It is detected by gustatory receptors, Gr21a and Gr63a, found in the ab1C neuron in basiconic sensilla on the third antennal segment. Volatile substances that modulate the receptors' function are of interest for pest control. While several substances block ab1C neurons or mimic the activating effect of carbon dioxide, it is not known if these substances are indeed ligands of the CO2 receptor or might act on other proteins in the receptor neuron. In this study, we used the recombinant Xenopus laevis expression system and two-electrode voltage-clamp technology to investigate the receptor function. We found that application of sodium bicarbonate evokes large inward currents in oocytes co-expressing Gr21a and Gr63a. The receptors most likely form hetromultimeric complexes. Homomultimeric receptors of Gr21a or Gr63a are sufficient for receptor functionality, although oocytes gave significantly lower current responses compared to the probable heteromultimeric receptor. We screened for putative blockers of the sodium bicarbonate response and confirmed that some of the substances identified by spike recordings of olfactory receptor neurons, such as 1-hexanol, are also blockers in the Xenopus oocyte system. We also identified a new blocking substance, citronellol, which is related to insect repellents. Many substances that activate receptor neurons were inactive in the Xenopus oocyte system, indicating that they may not be ligands for the receptor, but may act on other proteins. However, methyl pyruvate and n-hexylamine were found to be activators of the recombinant Gr21a/Gr63a receptor. [ABSTRACT FROM AUTHOR]

The study of the semiochemicals produced by the flowers of Impatiens spp. is an important topic that may explain the reason for the rapid expansion of some species in this genus. Impatiens L. belongs to the Balsaminaceae family, which includes several species considered to be invasive plants in Europe. This study aimed to characterize the phytochemistry of four naturally occurring plant species in Poland, including three invasive alien taxa (Impatiens parviflora, I. glandulifera, and I. capensis) and one native species (I. noli-tangere). Gas chromatographic techniques were used to assess phytochemical profiles of chemical attractant cues in their pollination biology. We detected differences in the scent profiles of the investigated species. All the examined Impatiens species produce various alcohols, i.e., heptacosanol, octacosanol, aldehydes (e.g., octadecanal, eicosanal, etc.), and fatty acids, as well as long-chain hydrocarbons such as dodecane, tricosane, petacosane, hexacosane, and farnesene. Impatiens parviflora, I. glandulifera, and I. capensis produce geraniol and linalool, which attract members of the Apidae family, including bumblebees and honeybees. Impatiens parviflora also produces linalool-derived monoterpenes (linalool oxide and 8-hydroxylinalool), which are a strong attractant for Diptera; this may clarify why the species is mainly visited and pollinated by syrphid flies. A list of insect visitors to the Impatiens species under study can be found in the article. [ABSTRACT FROM AUTHOR]

Objective To explore whether exposure to household insect repellents and insecticides is associated with anxiety symptoms among older adults, and the sensitive population in this relationship. Methods Based on the data of Chinese Longitudinal Healthy Longevity Survey (CLHLS) in 2018, anxiety symptoms were assessed using the 7 一 item Generalized Anxiety Disorder Scale (GAD - 7), and the information of household insect repellents and insecticides use of the elderly was collected by face - to - face questionnaire. We used multivariate logistic regression to evaluate the effects of household insect repellents and insecticides on and anxiety. Subgroup analysis was used to clarify the relationship between household insect repellents and insecticides and anxiety symptoms of the elderly in different subgroups. Results A total of 14 286 participants aged 65 years and older were included and 1 720(12. 04%) had anxiety symptoms. Compared with never or rarely users, the anxiety symptoms in the high exposure group increased significantly (OR = 1.35, 95% CI: 1. 14 - 1. 60). We found no significant association between household insecticides and anxiety symptoms. In addition, the study associations were pronounced among female (OR = 1.51, 95% CI:1. 17 -1.95), less than 80 years old (OR = 1. 46, 95% CI: 1. 22 - 1. 74), better socioeconomic status (OR = 1.48, 95% CI: 1. 18 -1. 86) and living in the rural (OR = 1. 35, 95% CI: 1. 14 - 1. 60) elderly. Conclusion We linked household insect repellents exposure to elevated risks of anxiety symptoms prevalence in the older adults. Confirmation these associations by prospective evidence is warranted. [ABSTRACT FROM AUTHOR]

Mechanisms of carrion insect succession have been interpreted separately from interspecific interactions between early and later colonists or from changes in volatile organic compounds perceived by insects resulting from the progression of decomposition. To link these perspectives, we examined through laboratory and field experiments whether the modification of volatile organic compounds by early colonists could be a mechanism of succession. In the laboratory experiment, we used Necrophila japonica (Coleoptera, Staphylinidae) as an early colonist and examined its effects on the emissions of important volatile attractants for carrion insects, dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) from carcasses. We collected DMDS and DMTS, using the static headspace method, under the following conditions: (i) rat carcass, (ii) rat carcass with artificial damage to the abdomen, (iii) rat carcass fed on by 10 Ne. japonica individuals, and (iv) 10 Ne. japonica individuals, and analyzed the collected gases using a gas chromatograph‐mass spectrometer. After 12 and 30 h, carcasses fed on by Ne. japonica emitted higher concentrations of DMDS and DMTS than in other conditions. In the field experiment, we examined the effects of DMDS and DMTS on the attraction of carrion insects using traps baited with a mixture of DMDS and DMTS, hexane (odors unrelated to carcasses), or an empty microtube. Traps baited with DMDS and DMTS attracted more necrophagous species and individuals than traps not baited with this combination. These results showed that accelerated emissions of DMDS and DMTS from carcasses caused by early colonists may contribute to community assembly during carrion insect succession. [ABSTRACT FROM AUTHOR]

Entomopathogenic fungi are the most versatile and potential biocontrol agents, due to their adaptability, mode of entry, persistent nature and wide host range. The present study aimed to isolate and identify the native entomopathogenic fungi for the biocontrol of major sucking insect pests of floriculture. Eighty-one fungal isolates were isolated from 55 soil samples and 26 infected insect cadavers were collected from the eastern and southern dry zones of Karnataka, India. Serial dilution and plating techniques, and insect bait techniques were followed. The insecticidal activity of fungal isolates against aphids, mites, 2nd instar larvae of thrips and whitefly nymphs was determined by leaf disc bioassay under in vitro conditions. The results of the experiment revealed that among 81 fungal isolates, sixteen (19.25 %) exhibited insecticidal activity against test insects and further, a distribution study revealed that 50 per cent of EPF isolates were belonging to genera Beauveria and Metarhizium (25% each), 18.75% Aspergillus, 12.50% were Lecanicillium spp. and 13% were Paecilomyces spp. (6.25%) and Hirsutella spp. (6.25 %) respectively. It was concluded that the recovery rate of EPF is lower with 19.5% and the dominant genera of EPFs are Beauveria and Metarhizium. This show EPFs with broader host rage will have more chances of survival and the same criteria can be used for the selection of efficient EPFs. [ABSTRACT FROM AUTHOR]