Chiral three-dimensional supramolecular assemblies: colloidal onions, cubosomes, and hexosomes.

Amphiphilic molecules can self-assemble in solution into a variety of supramolecular assemblies, ranging from simple micelles, ribbons, and tubes to complex cubosomes with bicontinuous cubic nanostructures. It is well known that the self-assembly of chiral building blocks into one-dimensional (1D) twisted fibers, helical ribbons, and tubes enables chiral transfer from the molecular scale to super-assemblies. In this study, we investigate the chirality of three-dimensional (3D) supramolecular assemblies, such as colloidal onions, cubosomes, and hexosomes, formed from the same chiral heteroclusters. Unlike supramolecular 1D helical ribbons, these assemblies do not have chiral external shapes or chiral internal nanostructures, but they do exhibit circular dichroism, suggesting that they are chiral. Structural studies revealed that the ordered arrangement of the chiral units in curved superstructures is the origin of the supramolecular chirality of these 3D assemblies. Therefore, this study provides insights for enriching the diversity and complexity of supramolecular chiral assemblies.

Automatic Meter Reading from UAV Inspection Photos in the Substation by Combining YOLOv5s and DeeplabV3.

The combination of unmanned aerial vehicles (UAVs) and artificial intelligence is significant and is a key topic in recent substation inspection applications; and meter reading is one of the challenging tasks. This paper proposes a method based on the combination of YOLOv5s object detection and Deeplabv3+ image segmentation to obtain meter readings through the post-processing of segmented images. Firstly, YOLOv5s was introduced to detect the meter dial area and the meter was classified. Following this, the detected and classified images were passed to the image segmentation algorithm. The backbone network of the Deeplabv3+ algorithm was improved by using the MobileNetv2 network, and the model size was reduced on the premise that the effective extraction of tick marks and pointers was ensured. To account for the inaccurate reading of the meter, the divided pointer and scale area were corroded first, and then the concentric circle sampling method was used to flatten the circular dial area into a rectangular area. Several analog meter readings were calculated by flattening the area scale distance. The experimental results show that the mean average precision of 50 (mAP50) of the YOLOv5s model with this method in this data set reached 99.58%, that the single detection speed reached 22.2 ms, and that the mean intersection over union (mIoU) of the image segmentation model reached 78.92%, 76.15%, 79.12%, 81.17%, and 75.73%, respectively. The single segmentation speed reached 35.1 ms. At the same time, the effects of various commonly used detection and segmentation algorithms on the recognition of meter readings were compared. The results show that the method in this paper significantly improved the accuracy and practicability of substation meter reading detection in complex situations.

The Effects of Processing on Bioactive Compounds and Biological Activities of Sorghum Grains.

Sorghum is ranked the fifth most commonly used cereal and is rich in many kinds of bioactive compounds. Food processing can affect the accumulation and decomposition of bioactive compounds in sorghum grains, and then change the biological activities of sorghum grains. The present review aims to analyze the effects of processing technologies on bioactive compounds and the biological activities of sorghum grains. Decortication reduces the total phenols, tannins, and antioxidant activity of sorghum grains. The effects of thermal processes on bioactive compounds and potential biological activities of sorghum grains are complicated due to thermal treatment method and thermal treatment conditions, such as extrusion cooking, which has different effects on the bioactive compounds and antioxidant capacity of sorghum due to extrusion conditions, such as temperature and moisture, and food matrices, such as whole grain and bran. Emerging thermal processes, such as microwave heating and high-pressure processing, could promote the release of bound phenolic substances and procyanidins, and are recommended. Biological processes can increase the nutritive and nutraceutical quality and reduce antinutritional compounds, except for soaking which reduces water-soluble compounds in sorghum.

Symmetry and Topology of Twin Boundaries and Five-Fold Twin Boundaries in Soft Crystals.

Heteroclusters constructed by tethering dissimilar nanoclusters using organic linkers resemble lipids and self-assemble into cubosomes, namely, microparticles of soft crystals composed of unique nanochannel lattices with a defined symmetry and topology. The internal porous crystal structures can be accurately characterized using transmission electron microscopy. We herein describe twin boundaries and five-fold twin boundaries in cubosomes with a double-diamond Pn3̅m structure. Our analysis indicates a clear distinction in the conformation of the skeletal unit: a centrosymmetric staggered conformation with point group D3d for the normal skeletal unit and a mirror-symmetric eclipsed one with point group D3h for the skeletal unit on the twin boundary. This symmetry distinction causes the channels to change direction and elongate slightly as they pass through the twin boundary, but the topology is maintained. For cubosomes containing five-fold twin boundaries, one of the channels is in the center of the particles seamlessly connecting the five blocks. Our conclusion is that the two distinct channel systems are still continuous. This fundamental understanding will contribute to the development of soft crystals with defined shapes and special inner nanostructures for advanced applications.

Effects of ultrafine grinding on physicochemical, functional and surface properties of ginger stem powders.

BACKGROUND: Ginger stem (GS) is a by-product of ginger processing. It is not directly edible as a feed or food, which leads to it being discarded as waste or burned. Accordingly, it is very important to develop new functional products in the food or feed industry as a result of high nutritional and medicinal values. In the present study, the structures and physicochemical properties of GS powders of different sizes were evaluated after ultrafine grinding by a vibrating mill. RESULTS: The ultrafine powders exhibited a smaller particle size and uniform distribution. Higher values in bulk density (from 1.07 ± 0.06 to 1.62 ± 0.08 g mL-1 ), oil holding capacity (from 3.427 ± 0.04 to 4.83 ± 0.03 g mL-1 ), and repose and slide angles (from 42.33 ± 1.52 to 54.36 ± 1.15° and 33.62 ± 0.75 to 47.27 ± 1.34°, respectively) of ultrafine GS powders were exhibited compared to coarse powders. With a reduced particle size, the solubility of ultrafine powders increased significantly (P < 0.05), whereas the water holding and swelling capacities decreased with a reduced particle size and then increased. Fourier transform infrared spectroscopy analysis showed that ultrafine grinding did not damage the main cellular structure of GS powder. The reduction of fiber length and particle size in GS was observed by light microscopy and scanning electron microscopy. The X-ray diffraction patterns demonstrated the crystallinity and the intensity of the peak in superfine GS powders. CONCLUSION: The present study suggests that ultrafine grinding treatments influence the structures and physicochemical properties of GS powders, and such changes would improve the effective utilization of GS in the food or feed industry. © 2020 Society of Chemical Industry.

Unraveling the Self-Assembly of Heterocluster Janus Dumbbells into Hybrid Cubosomes with Internal Double-Diamond Structure.

Cubosomes are bicontinuous cubic-phase particles generated by amphiphile self-assembly with bicontinuous cubic phases, which creates an intricate network of interconnected nanochannels that endow these materials with special functions for advanced applications. On the other hand, clusters are an attractive class of molecules that exhibit intriguing functions and properties that differ from those of atoms and nanoparticles. Inspired by lipid self-assembly and attracted to the new functionalities of clusters, we prepared special heterocluster Janus dumbbells (HCJDs) composed of dissimilar nanoclusters: namely, a polyoxometalate and a polyhedral oligomeric silsesquioxane. HCJDs resemble conventional amphiphiles and, as such, they self-assemble in solution into faceted hybrid cubosomes via the transformation of vesicles into spongelike aggregates. Multiple mechanisms that lead to equilibrium, including molecular self-assembly, vesicle accumulation, membrane fusion, inner-structure reorganization, and cubic crystal growth, contributed to the overall process. On the basis of these results, we proposed a strategy for self-assembly-from basic molecular design that goes beyond traditional amphiphiles to the construction of micro- or nanomaterials with hierarchical structures and advanced functions.

Effect of packaging methods and storage conditions on quality characteristics of flour product naan.

The quality characteristics of naan from flour products under various packaging methods stored at different temperatures (25, 4 and - 20 °C) for different time (0-49 days) were investigated. Packaging methods included ordinary plastic packaging (OPP), vacuum packaging (VP) and deoxygenation packaging (DP). Sensory value, acid value, moisture content and microbial count of naan during storage were evaluated. The results showed that the total demerit points of sensory of DP naan stored at 25 °C had considerably lower levels. The moisture content of naan in DP and VP at 25 °C during storage had not been affected, while in OPP increased; the acid values of naan increased, but in DP was the lowest; the total microbiological count (MC) of naan in OPP, VP and DP at 5th day reached 2.25, 3.04 and 1.99 log CFU g-1, respectively. At 4 and - 20 °C, the moisture content of naan in OPP, VP and DP during storage reduced, the acid values at storage the 38th day dramatically increased (p < 0.05), the MC slowly increased, but these in DP samples was lower. The Ultraviolet (UV) and microwave (MW) radiation time was varied to study its effect on the shelf life of naan at 25 °C. The moisture content of UV and MW treated naan were not significantly different from those of control naan (p > 0.05), but the demerit points, acid values and MC reduced, the shelf life of naan was extended. The combination of DP and MW methods was a better efficient way to reduced negative quality changes of naan during storage.

Optimization of AOT reversed micelle forward extraction of 7S globulin subunits from soybean proteins.

The work attempted to study on separating the α', α and ß subunits of 7S globulin from soybean proteins by reverse micelles. The effects of six single factors (W0, time, temperature, pH, surfactant concentration and salt solution species) on three subunit partitioning were discussed. The main influence factors (time, temperature and surfactant concentration) were optimized by the response surface test (Box-Behnken design, three factor three level) in order to optimize the forward extracting three subunits of 7S globulin. It was observed that the independent factor had substantial effect on the forward extraction yield of three subunits of 7S globulin. The statistical analysis showed that the reverse micelles could significantly affect the forward extraction efficiency of protein subunits. The highest forward extraction efficiency of α', α and ß subunits achieved 78.21, 63.65 and 61.34%, respectively. The proposed method also showed that the forward extraction efficiency of subunits with larger molecular weight was higher than low molecular weight.

Generic tags for Mn(ii) and Gd(iii) spin labels for distance measurements in proteins.

High-affinity chelating tags for Gd(iii) and Mn(ii) ions that provide valuable high-resolution distance restraints for biomolecules were used as spin labels for double electron-electron resonance (DEER) measurements. The availability of a generic tag that can bind both metal ions and provide a narrow and predictable distance distribution for both ions is attractive owing to their different EPR-related characteristics. Herein we introduced two paramagnetic tags, 4PSPyMTA and 4PSPyNPDA, which are conjugated to cysteine residues through a stable thioether bond, forming a short and, depending on the metal ion coordination mode, a rigid tether with the protein. These tags exhibit high affinity for both Mn(ii) and Gd(iii) ions. The DEER performance of the 4PSPyMTA and 4PSPyNPDA tags, in complex with Gd(iii) or Mn(ii), was evaluated for three double cysteine mutants of ubiquitin, and the Gd(iii)-Gd(iii) and Mn(ii)-Mn(ii) distance distributions they generated were compared. All three Gd(iii) complexes of the ubiquitin-PyMTA and ubiquitin-PyNPDA conjugates produced similar and expected distance distributions. In contrast, significant variations in the maxima and widths of the distance distributions were observed for the Mn(ii) analogs. Furthermore, whereas PyNPDA-Gd(iii) and PyNPDA-Mn(ii) delivered similar distance distributions, appreciable differences were observed for two mutants with PyMTA, with the Mn(ii) analog exhibiting a broader distance distribution and shorter distances. ELDOR (electron-electron double resonance)-detected NMR measurements revealed some distribution in the Mn(ii) coordination environment for the protein conjugates of both tags but not for the free tags. The broader distance distributions generated by 4PSPyMTA-Mn(ii), as compared with Gd(iii), were attributed to the distributed location of the Mn(ii) ion within the PyMTA chelate owing to its smaller size and lower coordination number that leave the pyridine nitrogen uncoordinated. Accordingly, in terms of distance resolution, 4PSPyNPDA can serve as an effective generic tag for Gd(iii) and Mn(ii), whereas 4PSPyMTA is efficient for Gd(iii) only. This comparison between Gd(iii) and Mn(ii) suggests that PyMTA model compounds may not predict sufficiently well the performance of PyMTA-Mn(ii) as a tag for high-resolution distance measurements in proteins because the protein environment can influence its coordination mode.

Influence of pH and salt concentration on functional properties of walnut protein from different extraction methods.

The effect of pH and NaCl on solubility and functional properties of walnut proteins obtained through AOT reverse micelles, enzyme-assisted reverse micelles and aqueous phase extraction methods was investigated and compared. Extraction yield, foaming properties, water holding capacities of protein obtained through enzyme-assisted reverse micelles at pH 2-12 and NaCl concentration 0.1-1 M were significantly higher than those of the AOT reverse micelles and aqueous phase extracted two. The solubility of proteins by AOT reverse micelles and enzyme-assisted reverse micelles at certain pH and NaCl concentration had no significant difference, but was higher that of the aqueous buffer. Oil holding capacity of three proteins was 2.35, 3.96 and 1.08 cm3/g, respectively. At pH 6-12 and NaCl concentration 0.1-1 M, the emulsifying activity of protein from AOT reverse micelles was higher than those of other two methods, while the emulsifying stability of protein from enzyme-assisted reverse micelles was the highest. The functional properties of walnut proteins were affected by extraction methods. It indicated that the walnut protein might be potentially applied in food industry as a food ingredient.

Citric acid treatment inhibits fading of sorghum (Sorghum bicolor) by modulating the accumulation of flavonoids.

Sorghum seeds can discolor during storage. Treatment of seeds with citric acid improves sensory quality and antioxidant activity. This study compared the differences in phenotypic and antioxidant activity between citric acid-treated and water-treated sorghum seeds. The study used transcriptomics and metabolomics approaches to investigate the regulatory mechanisms. The ∆a, ∆b and ∆l values of citric acid-treated sorghum seeds significantly increased after 6 months of storage. The SOD, POD and CAT enzyme activities of the citric acid-treated group were 1.94, 1.91 and 2.45 times higher than those of the control, respectively. The joint transcriptome and metabolome analysis showed that the citric acid-induced changes were mainly focused on the flavonoid biosynthetic pathway. Citric acid treatment up-regulated CHS, ANR, MYB and bHLH genes and promoted flavonoid accumulation. In conclusion, citric acid treatment promotes flavonoid accumulation, delays sorghum seed discoloration, and enhances antioxidant activity and storage life.

Influence of germination on the bioactivity, structural, functional and volatile characteristics of different chickpea flours.

In this paper, the objective was to evaluated the impact of germination of chickpea cultivars (Muying1, Y2-514 and YZ-364) on the bioactivity, volatiles and functional properties. The results showed that the Vitamin C content of Muying1, Y2-514 and YZ-364 after germination significantly increased (p < 0.05). Moreover, the germination also caused a significant decrease in lower transition temperatures and enthalpy values in chickpea flours (p < 0.05). After germination treatment, ß-sheet and random coils in protein secondary structures increased and ß-turn decreased in YZ-364; α-helix, ß-sheet and random coil in Y2-514 and Muying1 decreased, while ß-turn increased. The germination significantly enhanced the functional properties of three chickpea flours (p < 0.05). It was proved that the germination significantly enhanced the total phenolic and flavonoids content, antioxidant activity and in vitro protein digestibility. The GC-IMS revealed that the germination could affect the contents of volatile compounds of chickpea flours.

Design and evaluation of an efficient mosquito trap.

BACKGROUND: Vector mosquito control is important for preventing and controlling mosquito-borne infectious diseases. This study designed and developed a mosquito killer (MK) with a specific light wavelength, simulated human body temperature, human odor, and a photocatalyst to stimulate CO2 based on the physiological characteristics and ecological habits of mosquitoes. We tested the trapping effect of individual and multiple mosquito-trapping elements of the MK through two-way selection experiments and compared them with several commercial mosquito traps. RESULTS: The 365 nm wavelength MK was significantly more effective than the 395 nm (Cx. quinquefasciatus: 62.00% vs. 34.25%; Ae. albopictus: 50.75% vs 45.00%, An. sinensis: 49.75% vs 39.00%). Mosquitoes captured by the MK with heaters at 365 nm were significantly more than those captured by the MK without heaters at 365 nm. A trap with a 365 nm wavelength, heating element, and lure showed significantly better capture effectiveness than MK with a 365 nm wavelength, heating element, but without lure (Cx. quinquefasciatus: 67.00% vs. 29.75%, Ae. albopictus: 60.25% vs 36.25%, An. sinensis: 49.75% vs 39.75%). The coated photocatalyst trap with a 365 nm wavelength, heating element, and lure showed significantly better capture effectiveness than the trap without coating (Cx. quinquefasciatus: 54.25% vs. 42.50%; Ae. albopictus: 53.50% vs 44.00%, An. sinensis: 50.00% vs 41.25%). This trap demonstrated a significantly better capture advantage for Cx. quinquefasciatus and Ae. albopictus compared to the three commercial products. CONCLUSION: The developed mosquito trap with multiple attractant factors significantly enhanced the capture effectiveness of common mosquitoes. © 2024 Society of Chemical Industry.

miR-2940-1 is involved in the circadian regulation of oviposition in Aedes albopictus.

The vast majority of all global species have circadian rhythm cycles that allow them to adapt to natural environments. These regular rhythms are regulated by core clock genes and recent studies have also implicated roles for microRNAs in this regulation. Oviposition is an important circadian behavior in the reproductive cycle of insect vectors of diseases, and little is known about the rhythm or its regulation in mosquitoes. Aedes albopictus is a diurnal mosquito that transmits arboviruses and is the major cause of outbreaks of dengue fever in China. We analyzed the oviposition rhythm patterns of A. albopictus under different light/dark conditions and show that the mosquitoes have an oviposition peak between zeitgeber time 9 (ZT 9) and ZT 12. Furthermore, the antagomir-mediated knockdown of expression of the microRNA miR-2940-1 affected the oviposition rhythm of A. albopictus. These data support the conclusion that miR-2940-1 is involved in the regulation of oviposition rhythm in A. albopictus and provide a foundation for using oviposition rhythms as a new target for vector mosquito control.

The Effect of Combining Millet and Corn Straw as Source Forage for Beef Cattle Diets on Ruminal Degradability and Fungal Community.

Three ruminal cannulated Simmental crossbreed bulls (approximately 3 years of age and with 380 ± 20 kg live weight at initiation of the experiment) were used in a 3 × 3 Latin square experiment in order to determine the effects of the treatments on ruminal pH and degradability of nutrients, as well as the rumen fungal community. The experimental periods were 21 d, with 18 d of adjustment to the respective dietary treatments and 3 d of sample collection. Treatments consisted of a basal diet containing a 47.11% composition of two sources of forage as follows: (1) 100% millet straw (MILLSTR), (2) 50:50 millet straw and corn straw (COMB), and (3) 100% corn straw (CORNSTR). Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) were tested for ruminal degradability using the nylon bag method, which was incubated for 6, 12, 24, 36, 48, and 72 h, and rumen fungal community in rumen fluid was determined by high-throughput gene sequencing technology. Ruminal pH was not affected by treatments. At 72 h, compared to MILLSTR, DM degradability of CORNSTR was 4.8% greater (p < 0.05), but when corn was combined with millet straw, the difference in DM degradability was 9.4%. During the first 24 h, degradability of CP was lower for CORNSTR, intermediate for MILLSTR, and higher for COMB. However, at 72 h, MILLSTR and COMB had a similar CP degradability value, staying greater than the CP degradability value of the CORNSTR treatment. Compared to MILLSTR, the rumen degradability of NDF was greater for CORNSTR and intermediate for the COMB. There was a greater degradability for ADF in CORNSTR, intermediate for COMB, and lower for MILLSTR. In all treatments, Ascomycota and Basidiomycota were dominant flora. Abundance of Basidiomycota in the group COMB was higher (p < 0.05) than that in the group CORNSTR at 12 h. Relative to the fungal genus level, the Thelebolus, Cladosporium, and Meyerozyma were the dominant fungus, and the abundance of Meyerozyma in COMB and CORNSTR were greater (p < 0.05) than MILLSTR at 12, 24, and 36 h of incubation. In conclusion, it is suggested to feed beef cattle with different proportions of millet straw and corn straw combinations.

Chsy1 deficiency reduces extracellular matrix productions and aggravates cartilage injury in osteoarthritis.

Osteoarthritis (OA) is a kind of degenerative joint disease marked by the destruction of articular cartilage due to the degeneration of chondrocytes. CHSY1, one of the glycosyltransferases, is involved in the synthesis of chondroitin sulfate. Herein, we found that the expression of Chsy1 was decreased in the knee cartilage of OA rats. In order to investigate the role of CHSY1 in chondrogenesis and OA, we established a Chsy1 stable knockdown cell line in mouse ATDC5 chondrocytes by lentivirus. It was found that Chsy1 deficiency resulted in a reduction of extracellular matrix production in chondrocytes and a promotion of endochondral osteogenesis, which was indicated by the decreased expression of early chondrocytes genes (Col2a1, Sox9), and the increased expression of cartilage hypertrophy genes (Col10a1, Runx2, Mmp13, Mmp3). The expression trend of these genes is considered to be the characteristic of osteoarthritis. In addition, knockdown of Chsy1 could upregulate BMP signaling in differentiated chondrocytes, whereas Chsy1 overexpression had opposite effects. The reduction of extracellular matrix production and the promotion of endochondral osteogenesis by Chsy1 knockdown could be rescued by BMP signaling inhibitor LDN193189. Furthermore, the abnormally enhanced BMP signaling and the high expression of OA biomarker Mmp3 in primary cells of OA rats could be rescued by either LDN193189 or Chsy1 overexpression. These results implicate a role for Chsy1 in regulating extracellular matrix production and endochondral osteogenesis through BMP signaling; and a lack of Chsy1 could aggravate the cartilage damage of osteoarthritis.

Cold plasma effects on the nutrients and microbiological quality of sprouts.

Sprouts have been more and more popular among people all over the world due to their health benefits and good taste. Cold plasma (CP) is a promising and efficient nonthermal technology that has been applied to various aspects, including seed germination, plant growth, the synthesis of secondary metabolites. This review aims to represent the current knowledge status and future insights of CP on germination, nutritional quality and microbial inactivation of sprouts, and influencing mechanism was also discussed. CP under favorable conditions can promote the growth of sprouts, thus increase the yield of sprouts and microgreens. Numerous studies suggest that CP can promote the accumulation of bioactive compounds in sprouts, and subsequently enhance biological activities and so on the antioxidant capacity and antiproliferative effect. CP is an effective method for the inactivation of microorganisms on seeds and sprouts by reactive species. Therefore, CP is a promising technology for the sustainable development of sprouts industry.

An extracellular matrix biosensing mimetic for evaluating cathepsin as a host target for COVID-19.

To combat the new virus currently ravaging the whole world, every possible anti-virus strategy should be explored. As the main strategy of targeting the virus itself is being frustrated by the rapid mutation of the virus, people are seeking an alternative "host targeting" strategy: neutralizing proteins in the human body that cooperate with the virus. The cathepsin family is such a group of promising host targets, the main biological function of which is to digest the extracellular matrix (ECM) to clear a path for virus spreading. To evaluate the potential of cathepsin as a host target, we have constructed a biosensing interface mimicking the ECM, which can detect cathepsin from 3.3 pM to 33 nM with the limit of detection of 1 pM. Based on our quantitative analysis enabled by this biosensing interface, it is clear that patients with background diseases such as chronic inflammation and tumor, tend to have higher cathepsin activity, confirming the potential of cathepsin to serve as a host target for combating COVID-19 virus.

Clock genes regulate mating activity rhythms in the vector mosquitoes, Aedes albopictus and Culex quinquefasciatus.

BACKGROUND: Endogenous circadian rhythms result from genetically-encoded molecular clocks, whose components and downstream output factors cooperate to generate cyclic changes in activity. Mating is an important activity of mosquitoes, however, the key aspects of mating rhythm patterns and their regulatory mechanisms in two vector mosquito species, Aedes albopictus and Culex quinquefasciatus, remain unclear. METHODOLOGY/PRINCIPAL FINDINGS: We determined and compared the diel mating activity rhythms of these two mosquito species and discovered that Ae. albopictus had mating peaks in the light/dark transition periods (ZT0-3 and ZT9-12), while Cx. quinquefasciatus only had a mating peak at ZT12-15. Knockouts of the clock (clk) orthologous genes (Aalclk and Cxqclk) resulted in phase delay or phase reversal of the mating peaks in Ae. albopictus and Cx. quinquefasciatus, respectively. In addition, the temporal expression pattern of the desaturase orthologous genes, desat1, in both mosquito species was also different in respective wild-type strains and showed phase changes similar to the mating rhythms in clk mutant strains. Inhibition of desat1 expression resulted in decreased mating activity in male mosquitoes of both species but not females. In addition, desat1 regulated cuticular hydrocarbons' synthesis in both species. Silencing desat1 in male Ae. albopictus resulted in decreases of nonadecane and tricosane, which promoted mating, with concomitant increases of heptacosane, which inhibited mating. Silencing desat1 in male Cx. quinquefasciatus also resulted in decreases of tricosane, which promoted mating. CONCLUSIONS/SIGNIFICANCE: These results suggest that Aalclk and Cxqclk have significant roles in the mating activity rhythms in both Ae. albopictus and Cx. quinquefasciatus by regulating the temporal expression of the desat1 gene under LD cycles, which affects sex pheromone synthesis and mating. This work provides insights into the molecular regulatory mechanism of distinct mating rhythm of Ae. albopictus and Cx. quinquefasciatus and may provide a basis for the control of these two important vector mosquitoes.

Interspecific mating bias may drive Aedes albopictus displacement of Aedes aegypti during its range expansion.

Aedes albopictus is the most invasive mosquito in the world and often displaces Ae. aegypti in regions where their populations overlap. Interspecific mating has been proposed as a possible cause for this displacement, but whether this applies across the range of their sympatry remains unclear. Aedes albopictus and Ae. aegypti collected from allopatric and sympatric areas in China were allowed to interact in cage experiments with different crosses and sex-choices. The results confirm that asymmetric interspecific mating occurs in these populations with matings between allopatric Ae. albopictus males and Ae. aegypti females being significantly higher (55.2%) than those between Ae. aegypti males and Ae. albopictus females (27.0%), and sympatric mosquitoes showed a similar but lower frequency bias, 25.7% versus 6.2%, respectively. The cross-mated females can mate second time (remate) with the respective conspecific males and the 66.7% remating success of female Ae. albopictus was significantly higher than the 9.3% of Ae. aegypti females. Furthermore, 17.8% of the matings of Ae. albopictus males exposed to mixed pools of Ae. albopictus and Ae. aegypti females and 9.3% of the matings of Ae. aegypti males with mixed Ae. aegypti and Ae. albopictus females were interspecific. The difference in the length of clasper between male Ae. albopictus (0.524 mm) and Ae. aegypti (0.409 mm) may be correlated with corresponding mates. We conclude that stronger Ae. albopictus male interspecific mating and more avid female intraspecific remating result in a satyr effect and contribute to competitive displacement of Ae. aegypti as allopatric Ae. albopictus invade during range expansion.