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1.
Pest Manag Sci ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459943

RESUMO

BACKGROUND: The ladybeetle, Coccinella septempunctata, an important predator, is widely used to control aphids, whiteflies, mites, thrips, and lepidopteran pests. Diapause control technology is key to extending C. septempunctata shelf-life and commercialization. Lipid accumulation is a major feature of reproductive diapause, but the function of AKH signaling as a regulator of lipid mobilization in reproductive diapause remains unclear. This study aimed to identify and characterize AKH and AKHR genes, and clarify their functions in reproductive diapause. RESULTS: The relative expression levels of CsAKH and CsAKHR were the highest in the head and fat body, respectively, and were significantly decreased under diapause conditions, both in developmental stages and tissues (head, midgut, fat body, and ovary). Furthermore, CsAKH and CsAKHR expression was increased significantly after juvenile hormone (JH) injection, but CsMet silencing significantly inhibited CsAKH and CsAKHR expression, whereas CsMet knockdown blocked the induction effect of JH. CsAKH and CsAKHR knockdown significantly reduced water content, increased lipid storage, and promoted the expression of genes related to lipid synthesis, but significantly blocked ovarian development, and induced forkhead box O (FOXO) gene expression in C. septempunctata under reproduction conditions. By contrast, injection of AKH peptide significantly inhibited FOXO expression, reduced lipid storage, and increased water content in C. septempunctata under diapause conditions. CONCLUSION: These results indicate that CsAKH and CsAKHR are involved in the regulation of lipid accumulation and ovarian development during diapause in C. septempunctata, and provide a promising target for manipulating C. septempunctata diapause. © 2024 Society of Chemical Industry.

2.
Sci Total Environ ; 924: 171329, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462006

RESUMO

Phenolic compounds, abundant secondary metabolites in plants, profoundly influence soil ecosystems, plant growth, and interactions with herbivores. In this study, we explore the intricate relationships between phenolics, soil microbes, and gall formation in Ageratina adenophora (A. adenophora), an invasive plant species in China known for its allelopathic traits. Using metabolomic and microbial profiling, significant differences in soil microbial composition and metabolite profiles were observed between bulk and rhizosphere soil samples. Phenolics influenced bacterial communities, with distinct microbial populations enriched in each soil type. Additionally, phenolics impacted soil metabolic processes, with variations observed in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis between different soil treatments. Analysis of phenolic content in plant and soil samples revealed considerable variations, with higher concentrations observed in certain plant tissues and soil types. Bioactive phenols extracted from plant and soil samples were identified using gas chromatography/mass spectrometry (GC-MS), providing insights into the diverse chemical composition of these compounds. Furthermore, the effects of phenolics on plant growth and gall formation were investigated. Phenols exhibited both stimulatory and inhibitory effects on plant growth, with optimal concentrations promoting emergence but higher concentrations hindering growth. Gall formation was influenced by phenolic concentrations, leading to structural alterations in stem tissue and gall morphology. Histochemical analysis revealed starch and lipid accumulation in gall tissues, indicating metabolic changes induced by phenolics. The presence of phenolics disrupted tissue structures and influenced vascular bundle orientation in gall tissues. Overall, our study highlights the multifaceted roles of phenolic compounds in soil ecosystems, plant development, and gall formation, facilitating the utilization of secondary metabolites in agriculture.


Assuntos
Ecossistema , Solo , Solo/química , Desenvolvimento Vegetal , Plantas/metabolismo , Fenóis/metabolismo , Dispersão Vegetal , Microbiologia do Solo , Raízes de Plantas/metabolismo
3.
Insect Mol Biol ; 33(1): 17-28, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37707297

RESUMO

In insects, vitellogenin (Vg) is generally viewed as a female-specific protein. Its primary function is to supply nutrition to developing embryos. Here, we reported Vg from the male adults of a natural predator, Chrysopa pallens. The male Vg was depleted by RNAi. Mating with Vg-deficient male downregulated female Vg expression, suppressed ovarian development and decreased reproductive output. Whole-organism transcriptome analysis after male Vg knockdown showed no differential expression of the known spermatogenesis-related regulators and seminal fluid protein genes, but a sharp downregulation of an unknown gene, which encodes a testis-enriched big protein (Vcsoo). Separate knockdown of male Vg and Vcsoo disturbed the assembly of spermatid cytoplasmic organelles in males and suppressed the expansion of ovary germarium in mated females. These results demonstrated that C. pallens male Vg signals through the downstream Vcsoo and regulates male and female reproduction.


Assuntos
Testículo , Vitelogeninas , Feminino , Masculino , Animais , Vitelogeninas/genética , Vitelogeninas/metabolismo , Insetos/genética , Reprodução , Gametogênese
4.
Nanoscale ; 16(1): 462-473, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38086655

RESUMO

Lithium-sulfur (Li-S) battery is one of the most promising next-generation energy-storage systems with a high energy density and low cost. However, their commercial applications face several challenges, such as the shuttle effect caused by the soluble lithium polysulfide (LiPSs) intermediates and the sluggish sulfur redox reaction. In this article, we systematically investigated the anchoring and electrochemical performance of a series of transition metal carbides (TMCs: TiC, VC, ZrC, NbC, HfC, TaC) as cathode materials for Li-S batteries by theoretical calculations. The lithiophilic/sulfiphilic non-polar (001) surfaces of TMCs can offer moderate binding strength with LiPS intermediates, ensuring good performance of sulfur immobilization. These TMCs can also facilitate lithium diffusion, indicating the good rate performance of Li-S batteries. We also demonstrated that the studied TMCs can be classified into two classes according to their catalytic activity for Li2S decomposition which originated from their different electronic structural features. Furthermore, TiC, ZrC, and HfC exhibited excellent bifunctional electrochemical activity through reducing the Gibbs free energy for sulfur reduction reactions (SRRs) and lowering the barrier for Li2S decomposition which facilitates accelerating electrode kinetics and elevating utilization of sulfur. Our results offer a systematic approach to designing and screening non-polar materials for high-performance Li-S batteries, based on the rational electronic structure and lattice match strategy.

5.
Small Methods ; : e2301206, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059756

RESUMO

In recent years, there have been significant advancements in Al-ion battery development, resulting in high voltage and capacity. Traditionally, only carbon-based materials with layered structures and strong bonding capabilities can deliver superior performance. However, most other materials exhibited low discharge voltages of 1.4 V, especially in aqueous Al-ion battery systems lacking anion intercalation. Thus, the development of high-voltage cathode materials has become crucial. This study introduces 2D MoS2 as a high-performance cathode for aqueous Al-ion batteries. The material's interlayer structure enables the intercalation of AlCl4 - anions, resulting in high-voltage intercalation. The resulting battery achieved a high voltage of 1.8 V with a capacity of 750 mAh g-1 , contributing to a high energy density of 890 Wh kg-1 and an impressive retention rate of ≈100% after 200 cycles. This research not only sheds light on the high-voltage anion-intercalation mechanism of MoS2 but also paves the way for the further development of advanced cathode materials in the field of Al-ion batteries. By demonstrating the potential of using 2D MoS2 as a cathode material, this finding can lead to the development of more efficient and innovative energy storage technologies, ultimately contributing to a sustainable and green energy future.

6.
Life (Basel) ; 13(10)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37895461

RESUMO

Flower-rich habitats are crucial for promoting biodiversity and ecosystem services within agricultural ecosystems, such as pollination and pest control. The present study investigates the efficacy of employing floral structures as a criterion for the selection of plant species in order to enhance the attraction of natural enemies within cucumber greenhouses, consequently augmenting floral resources. The results of our study provide evidence that flower strips have a beneficial effect on the fitness of critical natural predators, while not facilitating the proliferation of detrimental insect species. These findings exhibit potential for enhancing pest-management services in the agricultural sector. The findings of our study demonstrate that pest levels within greenhouse environments closely resemble those observed in real-world commercial cropping systems. As a result, the introduction of Coccinella septempunctata and Menochilus sexmaculatus biocontrol agents is confirmed to be a reliable and efficient method for pest management. The phenomenon of predator-prey density dependency is recognized as a crucial element in the implementation of biological control strategies. Furthermore, we investigate the impact of floral resources on the reproductive capacity of indigenous predators. The impact of Coriandrum sativum on fertility is substantial, indicating that the presence of a varied plant assortment with overlapping flowering periods can prolong the availability of floral resources. This study highlights the significance of flower-rich habitats and deliberate plant selection in augmenting biodiversity, ecosystem services, and pest management within agricultural settings. The implementation of conservation biological control technologies presents supplementary ecological advantages, thus offering practical implications for the promotion of sustainable agricultural practices.

7.
BMC Zool ; 8(1): 15, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37641154

RESUMO

BACKGROUND: Chrysopa pallens is one of the most beneficial and effective natural predators, and is famous for its extensive distribution, wide prey spectrum, and excellent reproductive performance. This study examined the anatomy and fine structure of the C. pallens reproductive system and spermatogenesis. RESULTS: The male reproductive system of C. pallens comprises a pair of testes, a vas deferens, seminal vesicles, accessory glands, and short ejaculatory ducts. The testes were already mature on the day of emergence, but the accessory glands did not mature until 5 days post-emergence. In early spermatids, the flagellum had an axoneme on one side of the two mitochondrial derivatives. The nucleus was surrounded by parallel crystalline and paracrystalline materials. The spermatid envelope extends towards the paracrystalline material in a tail-shaped wing. In mature spermatids, the axoneme is located between the two accessory bodies and mitochondrial derivative sets. The parallel-crystalline and paracrystalline materials disappeared. In the testes, the wall of seminal cysts consists of a layer of epithelium, a muscular-connective sheath, and several vesicles of different sizes. The mature seminal cysts contained 128 spermatozoa. The accessory gland is composed of six parts: ventral papilla-like protuberance, anterior glandular lobe, lateral glandular lobe, seminal cyst, posterior kidney-shaped lobe, and posterior papilla-like protuberance. Muscle fibers and secretory granules are extensive. CONCLUSIONS: This study provides information on the reproductive system of C. pallens and offers a resource for taxonomy and reproductive biology.

8.
Sci Adv ; 9(32): eadh1181, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37556543

RESUMO

Mg-ion batteries offer a safe, low-cost, and high-energy density alternative to current Li-ion batteries. However, nonaqueous Mg-ion batteries struggle with poor ionic conductivity, while aqueous batteries face a narrow electrochemical window. Our group previously developed a water-in-salt battery with an operating voltage above 2 V yet still lower than its nonaqueous counterpart because of the dominance of proton over Mg-ion insertion in the cathode. We designed a quasi-solid-state magnesium-ion battery (QSMB) that confines the hydrogen bond network for true multivalent metal ion storage. The QSMB demonstrates an energy density of 264 W·hour kg-1, nearly five times higher than aqueous Mg-ion batteries and a voltage plateau (2.6 to 2.0 V), outperforming other Mg-ion batteries. In addition, it retains 90% of its capacity after 900 cycles at subzero temperatures (-22°C). The QSMB leverages the advantages of aqueous and nonaqueous systems, offering an innovative approach to designing high-performing Mg-ion batteries and other multivalent metal ion batteries.

9.
Phys Chem Chem Phys ; 25(29): 19795-19803, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449881

RESUMO

As one of the promising next-generation energy storage systems, lithium-sulfur (Li-S) batteries have been the subject of much recent attention. However, the polysulfide shuttle effect remains problematic owing to the dissolution of intermediate polysulfide species in the electrolyte and the sluggish reaction dynamics in Li-S batteries. To overcome these issues, this work reports an effective strategy for enhancing the electrochemical performance of Li-S batteries using single atom Zn doping on the S-terminated Ti2C MXenes (Ti2-xZnxCS2). Spin-polarized density functional theory (DFT) calculations were performed to elucidate the interactions of lithium polysulfides (LiPSs) and the Ti2-xZnxCS2 surface in terms of geometric and electronic properties, as well as the delithiation process of Li2S on the Ti2-xZnxCS2 surface. It is found that doping single atom Zn could induce a new Lewis acid-based sites, which could provide proper affinity toward LiPSs. Combined with the metallic character, a low Li diffusion barrier and high catalytic activity for the delithiation process of Li2S, makes Ti2-xZnxCS2 a promising cathode material for Li-S batteries. The results demonstrate the importance of surface chemistry and the electronic structure of MXenes in LiPSs' adsorption and catalysis capability. We believe that our findings provide insights into the recent experimental results and guidance for the preparation and practical application of MXenes in Li-S batteries.

10.
Small Methods ; 7(7): e2300280, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37086111

RESUMO

Ni-rich layered cathodes with ultrahigh nickel content (≥90%), for example LiNi0.9 Co0.1 O2 (NC0.9), are promising for next-generation high-energy Li-ion batteries (LIBs), but face stability issues related to structural degradation and side reactions during the electrochemical process. Here, surface modulation is demonstrated by integrating a Li+ -conductive nanocoating and gradient lattice doping to stabilize the active cathode efficiently for extended cycles. Briefly, a wet-chemistry process is developed to deposit uniform ZrO(OH)2 nanoshells around Ni0.905 Co0.095 (OH)2 (NC0.9-OH) hydroxide precursors, followed by high temperature lithiation to create reinforced products featuring Zr doping in the crust lattice decorated with Li2 ZrO3 nanoparticles on the surface. It is identified that the Zr4+ infiltration reconstructed the surface lattice into favorable characters such as Li+ deficiency and Ni3+ reduction, which are effective to combat side reactions and suppress phase degradation and crack formation. This surface control is able to achieve an optimized balance between surface stabilization and charge transfer, resulting in an extraordinary capacity retention of 96.6% after 100 cycles at 1 C and an excellent rate capability of 148.8 mA h g-1 at 10 C. This study highlights the critical importance of integrated surface modulation for high stability of cathode materials in next-generation LIBs.

11.
J Am Chem Soc ; 145(13): 7397-7407, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36961942

RESUMO

Nickel-rich layered oxides (NLOs) are considered as one of the most promising cathode materials for next-generation high-energy lithium-ion batteries (LIBs), yet their practical applications are currently challenged by the unsatisfactory cyclability and reliability owing to their inherent interfacial and structural instability. Herein, we demonstrate an approach to reverse the unstable nature of NLOs through surface solid reaction, by which the reconstructed surface lattice turns stable and robust against both side reactions and chemophysical breakdown, resulting in improved cycling performance. Specifically, conformal La(OH)3 nanoshells are built with their thicknesses controlled at nanometer accuracy, which act as a Li+ capturer and induce controlled reaction with the NLO surface lattices, thereby transforming the particle crust into an epitaxial layer with localized Ni/Li disordering, where lithium deficiency and nickel stabilization are both achieved by transforming oxidative Ni3+ into stable Ni2+. An optimized balance between surface stabilization and charge transfer is demonstrated by a representative NLO material, namely, LiNi0.83Co0.07Mn0.1O2, whose surface engineering leads to a highly improved capacity retention and excellent rate capability with a strong capability to inhibit the crack of NLO particles. Our study highlights the importance of surface chemistry in determining chemical and structural behaviors and paves a research avenue in controlling the surface lattice for the stabilization of NLOs toward reliable high-energy LIBs.

12.
Int J Cardiol ; 381: 88-93, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36914072

RESUMO

BACKGROUND: The aim of this study was to investigate the clinical characteristics of patients between active and inactive Takayasu's arteritis with pulmonary artery involvement (PTA) and to identify better markers of disease activity in these patients. METHODS: Sixty-four PTA patients in Beijing Chao-yang hospital (2011 to 2021) were included. According to National Institutes of Health criteria, 29 patients were in active stage and 35 were in inactive stage. Their medical records were collected and analyzed. RESULTS: Compared with inactive group, patients in active group were younger. More patients in active stage presented fever (41.38% vs 5.71%), chest pain (55.17% vs 20%), increased C-reactive protein (2.91 vs 0.46 mg/L), erythrocyte sedimentation rate (35.0 vs 9 mm/h), and platelet count (291 vs 221 × 109/L). Pulmonary artery wall thickening was more common in active group (51.72% vs 11.43%). These parameters were restored after treatment. The incidence of pulmonary hypertension was comparable between groups (34.48% vs 51.43%), but patients in active group had lower pulmonary vascular resistance (PVR) (361.0 vs 891.0 dyn·s·cm-5) and higher cardiac index (2.76 ± 0.72 vs 2.01 ± 0.58 L/min/m2). On multivariate logistic regression analysis, chest pain [odds ratio (OR) 9.37, 95%CI (1.98-44.38), P = 0.005], increased platelet count (>242.5 × 109/L) [OR 9.03, 95%CI (2.10-38.87), P = 0.003] and pulmonary artery wall thickening [OR 7.08, 95%CI (1.44-34.89), P = 0.016] were independently associated with disease activity. CONCLUSION: Chest pain, increased platelet count, and pulmonary artery wall thickening are potential new indicators of disease activity in PTA. Patients in active stage may have lower PVR and better right heart function.


Assuntos
Hipertensão Pulmonar , Arterite de Takayasu , Humanos , Arterite de Takayasu/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/epidemiologia , Dor no Peito/diagnóstico por imagem , Dor no Peito/epidemiologia
13.
Pest Manag Sci ; 79(8): 2891-2901, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36947672

RESUMO

BACKGROUND: Telenomus remus (Nixon) is a dominant natural enemy controlling the invasive pest Spodoptera frugiperda (J. E. Smith). Continuous rearing of egg parasitoids on alternative hosts is crucial for mass production and cost reduction. However, to ensure the effectiveness of natural enemy products against target pests in the field, it is necessary to evaluate the parasitoid quality during the mass-rearing process. Despite the successful rearing of this parasitoid on the alternative host Spodoptera litura (Fabricius) eggs, less attention has been paid to the quality of parasitoids continuously reared for multiple generations. Therefore, we evaluated the performance of T. remus reared on S. litura eggs for 30 generations via morphological characteristics, flight ability, and life table analysis. RESULTS: Wing length, wing width, body length, and right hind tibia length of T. remus did not differ among the different generations. However, the body length of female parasitoids was significantly longer than that of males for any generation. Although the proportion of 'flyers' and 'deformed' T. remus varied among generations, the flight ability did not decline significantly after rearing on S. litura eggs. Moreover, T. remus continuously reared on S. litura eggs maintained stable parasitism performance and life table parameters on the target host S. frugiperda eggs. CONCLUSION: S. litura eggs are suitable hosts for the mass-rearing of T. remus. This study can be subsequently used to guide the production and facilitate the application of T. remus in the control of S. frugiperda. © 2023 Society of Chemical Industry.


Assuntos
Produtos Biológicos , Besouros , Himenópteros , Animais , Masculino , Feminino , Spodoptera
14.
Soft Robot ; 10(4): 797-807, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36854131

RESUMO

Electrostatic adhesion, as a promising actuation technique for soft robotics, severely suffers from the failure caused by the unpredictable electrical breakdown. This study proposes a novel self-clearing mechanism for electrostatic actuators, particularly for electrostatic adhesion. By simply employing an enough thin conductive layer (e.g., <7 µm for copper), this method can spontaneously clear the conductor around the breakdown sites effectively once breakdowns onset and survive the actuator shortly after the electrical damage. Compared with previous self-clearing methods, which typically rely on new specific materials, this mechanism is easy to operate and compatible with various materials and fabrication processes. In our tests, it can improve the maximum available voltage by 260% and the maximum electrostatic adhesive force by 276%. In addition, the robustness and repeatability of the self-clearing mechanism are validated by surviving consecutive breakdowns and self-clearing of 173 times during 65 min. This method is also demonstrated to be capable of recovering the electrostatic pad from severe physical damages such as punctures, penetrations, and cuttings successfully and enabling stable and reliable operation of the electrostatic clutch, or gripping, for example, even after the short-circuit takes place for hundreds of times. Therefore, the proposed self-clearing method sheds new light on high performance and more extensive practical applications of electrostatic actuators in the future.

15.
J Chem Theory Comput ; 19(5): 1381-1387, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36812059

RESUMO

All-solid-state lithium-ion batteries have been a promising solution for next-generation energy storage due to their safety and potentially high energy density. In this work, we developed a density-functional tight-binding (DFTB) parameter set for modeling solid-state lithium batteries, focusing on the band alignment at electrolyte/electrode interfaces. Despite DFTB being widely applied in the simulation of large-scale systems, parametrization is usually done for single materials, and less attention is paid to band alignment among multiple materials. Band offsets at the electrolyte/electrode interfaces are key quantities determining the performance. Here, an automated global optimization method based on DFTB confinement potentials of all elements is developed, while the band offsets between electrodes and electrolytes are introduced as constraints during the optimization. The parameter set is applied to model an all-solid-state Li/Li2PO2N/LiCoO2 battery, and its electronic structure shows a good agreement with that from density-functional theory (DFT) calculations.

16.
Bull Entomol Res ; 113(1): 49-62, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35904166

RESUMO

Understanding predator-prey interactions is essential for successful pest management by using predators, especially for the suppression of novel invasive pest. The green lacewing Chrysopa formosa is a promising polyphagous predator that is widely used in the biocontrol of various pests in China, but information on the control efficiency of this predator against the seriously invasive pest Spodoptera frugiperda and native Spodoptera litura is limited. Here we evaluated the predation efficiency of C. formosa adults on eggs and first- to third-instar larvae of S. frugiperda and S. litura through functional response experiments and determined the consumption capacity and prey preference of this chrysopid. Adults of C. formosa had a high consumption of eggs and earlier instar larvae of both prey species, and displayed a type II functional response on all prey stages. Attack rates of the chrysopid on different prey stages were statistically similar, but the handling time increased notably as the prey developed. The highest predation efficiency and shortest-handling time were observed for C. formosa feeding on Spodoptera eggs, followed by the first-instar larvae. C. formosa exhibited a significant preference for S. litura over S. frugiperda in a two-prey system. In addition, we summarized the functional response and predation efficiency of several chrysopids against noctuid pests and made a comparison with the results obtained from C. formosa. These results indicate that C. formosa has potential as an agent for biological control of noctuid pests, particularly for the newly invasive pest S. frugiperda in China.


Assuntos
Controle Biológico de Vetores , Comportamento Predatório , Animais , Spodoptera/fisiologia , Taiwan , Larva/fisiologia , Comportamento Predatório/fisiologia
17.
Mitochondrial DNA B Resour ; 7(1): 120-122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34993333

RESUMO

Rhynocoris fuscipes (Fabricius 1787) is an important predator in China. In current study, the complete mitochondrial genome of R. fuscipes is determined. The mitogenome is 15,542 bp in size and comprises of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and a control region. Gene arrangement is identical to that of the putative ancestral arrangement of insects. All protein-coding genes initiate with ATN codons and terminate with TAA codons except for COII, ND4, and ND5 use TA or a single T residue as the termination codons. All tRNAs have the clover-leaf structure except for the tRNASer(AGN) and the length of them range from 62 to 70 bp. The phylogenetic result supports the monophyly of Harpactorinae and the sister relationship between R. fuscipes and Rhynocoris incertis.

18.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614060

RESUMO

Cathepsin L protease, which belongs to the papain-like cysteine proteases family, is an important player in many physiological and pathological processes. However, little was known about the role of cathepsin L in ladybird beetles (Coccinella septempuctata Linnaeus) during diapause. Here, we analyzed the characteristics of cathepsin L (CsCatL) in the females of C. septempunctata and its role during the diapause of the ladybeetle. CsCatL was cloned and identified from beetle specimens by rapid amplification of cDNA-ends (RACE). The cDNA sequence of CsCatL was 971 bp in length, including an 843 bp open reading frame encoding a protein of 280 amino acids. It was identified as the cathepsin L group by phylogenetic analysis. Knockdown of CsCatL by RNA interference led to decreased expression levels of fatty acid synthase 2 (fas 2) genes and suppressed lipid accumulation. Furthermore, silencing the CsCatL gene distinctly reduced diapause-related features and the survival of female C. spetempunctata under diapause-inducing conditions. The results suggested that the CsCatL gene was involved in fatty acid biosynthesis and played a crucial role in the survival of adult C. septempunctata during the diapause preparation stage.


Assuntos
Besouros , Diapausa , Animais , Feminino , Catepsina L/genética , Catepsina L/metabolismo , Filogenia , DNA Complementar , Besouros/metabolismo , Diapausa/genética , Lipídeos
19.
Insects ; 12(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34940138

RESUMO

Telenomus remus (Nixon) is a dominant egg parasitoid of the destructive agricultural pest Spodoptera frugiperda (J. E. Smith), and so is used in augmentative biocontrol programs in several countries. An optimized mass-rearing system is essential to produce biological control products in a timely and cost-effective manner. In this study, the photoperiod, host egg:parasitoid ratio, and exposure time were evaluated to identify the optimal rearing conditions for T. remus on the alternative host Spodoptera litura (Fabricius) eggs. Results showed that increasing photoperiod above 12L:12D remarkably improved parasitoid progeny yield and life table parameters. Overlong photoperiods shortened female longevity, but within acceptable limits. There was a significant negative correlation between parasitism rate and host egg:parasitoid ratio under exposure times of 12 and 36 h, but not 24 h. Percentage of female progeny increased significantly along with increasing the host egg:parasitoid ratio. A significant negative relationship between the number of emerged adults per egg and the host egg:parasitoid ratio was observed at an exposure time of 36 h. It was concluded that T. remus may be mass-reared most efficiently on S. litura eggs using a photoperiod of more than 12L:12D, a 14-20:1 host egg:parasitoid ratio, and an exposure time of 24 h. These findings can be used to produce T. remus more efficiently and at lower costs.

20.
Materials (Basel) ; 14(24)2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34947258

RESUMO

The AlNbTiZr medium-entropy alloy (MEA) coatings with different Al contents were prepared on N36 zirconium alloy substrates by RF magnetron co-sputtering. The morphology, microstructure, mechanical properties, surface wettability and corrosion resistance of the AlNbTiZr MEA coatings were studied to evaluate the surface protection behavior of zirconium alloy cladding under operation conditions of a pressurized water reactor. The results showed that all the coatings were composite structures with amorphous and bcc-structured nanocrystals. With the increase of Al content, both the elastic modulus and hardness decreased first and then increased. The hydrophobicity of the coatings was enhanced compared with that of the substrate. The 10.2 at.% Al AlNbTiZr coating had the best corrosion resistance and the minimum oxygen penetration depth, which originated from the formation of a denser oxide layer consisting of Nb2Zr6O17 and ZrO2. This study provides an improved idea for the design and development of Al-containing MEA coating materials for accident tolerant fuel.

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