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1.
Mol Ecol ; 31(21): 5568-5580, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35984732

RESUMEN

How invasive species cope with novel selective pressures with limited genetic variation is a fundamental question in molecular ecology. Several mechanisms have been proposed, but they can lack generality. Here, we addressed an alternative solution, polygenic adaptation, wherein traits that arise from multiple combinations of loci may be less sensitive to loss of variation during invasion. We tested the polygenic signal of environmental adaptation of Colorado potato beetle (CPB) introduced in Eurasia. Population genomic analyses showed declining genetic diversity in the eastward expansion of Eurasian populations, and weak population genetic structure (except for the invasion fronts in Asia). Demographic history showed that all populations shared a strong bottleneck about 100 years ago when CPB was introduced to Europe. Genome scans revealed a suite of genes involved in activity regulation functions that are plausibly related to cold stress, including some well-founded functions (e.g., the activity of phosphodiesterase, the G-protein regulator) and discrete functions. Such polygenic architecture supports the hypothesis that polygenic adaptation and potentially genetic redundancy can fuel the adaptation of CPB despite strong genetic depletion, thus representing a promising general mechanism for resolving the genetic paradox of invasion. More broadly, most complex traits based on polygenes may be less sensitive to invasive bottlenecks, thus ensuring the evolutionary success of invasive species in novel environments.


Asunto(s)
Escarabajos , Solanum tuberosum , Animales , Escarabajos/genética , Herencia Multifactorial/genética , Especies Introducidas , Hidrolasas Diéster Fosfóricas/genética
2.
Nanotechnology ; 30(9): 095401, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30523902

RESUMEN

We present an all-solid-state flexible and stretchable pseudocapacitor composed of dodecylbenzenesulfonate-doped polypyrrole (PPy(DBS))-coated vertically aligned carbon nanotubes (VACNTs) partially embedded in a polydimethylsiloxane (PDMS) substrate. VACNTs are grown via atmospheric-pressure chemical vapor deposition on a Si/SiO2 substrate and transferred onto PDMS. Then, the PPy(DBS) film is coated with a surface charge of 300 mC cm-2 on individual carbon nanotubes (CNTs) via electropolymerization. The partial embedment of VACNTs in PDMS permits a rapid and facile integration of the PPy(DBS)/CNTs/PDMS structure to construct a flexible and stretchable supercapacitor electrode. The measured capacitance is 3.6 mF cm-2 with a PVA-KOH gel electrolyte at a scan rate of 100 mV s-1, which is maintained under stretching from 0% to 150% and bending/twisting angles from 0° to 180°. This all-solid-state stretchable supercapacitor shows a stable galvanostatic performance during 10 000 charge/discharge cycles with its capacitance retained at 109%.

3.
Angew Chem Int Ed Engl ; 58(33): 11390-11394, 2019 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-31187584

RESUMEN

Low n-doping efficiency and inferior stability restrict the thermoelectric performance of n-type conjugated polymers, making their performance lag far behind of their p-type counterparts. Reported here are two rigid coplanar poly(p-phenylene vinylene) (PPV) derivatives, LPPV-1 and LPPV-2, which show nearly torsion-free backbones. The fused electron-deficient rigid structures endow the derivatives with less conformational disorder and low-lying lowest unoccupied molecular orbital (LUMO) levels, down to -4.49 eV. After doping, two polymers exhibited high n-doping efficiency and significantly improved air stability. LPPV-1 exhibited a high conductivity of up to 1.1 S cm-1 and a power factor as high as 1.96 µW m-1 K-2 . Importantly, the power factor of the doped LPPV-1 thick film degraded only 2 % after 7 day exposure to air. This work demonstrates a new strategy for designing conjugated polymers, with planar backbones and low LUMO levels, towards high-performance and potentially air-stable n-type polymer thermoelectrics.

4.
Proc Biol Sci ; 285(1877)2018 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-29695448

RESUMEN

Extant stick and leaf insects commonly imitate twigs or leaves, with lateral lamellae used to enhance crypsis or achieve mimicry for protection. However, the origin and early evolution of such lateral expansions among Phasmatodea are unknown, because all known Mesozoic phasmatodeans hitherto lack preserved evidence of such structures. We report here the first Mesozoic stick insect, Elasmophasma stictum gen. et sp. nov., with well-preserved, thin, lateral lamellae on the thoracic pleura, the terga of abdominal segments I-X and the ventrolateral margins of all femora. This new species, from the mid-Cretaceous amber of northern Myanmar, has a clear, stick-like body and is assigned to Euphasmatodea. The abdominal structures of E. stictum exhibit traces of multiple expansions of the terga, suggesting that such structure might have been an early development of body expansions used to improve crypsis for stick or leaf insects when they sprawled on twigs or leaves.


Asunto(s)
Evolución Biológica , Fósiles/anatomía & histología , Insectos/anatomía & histología , Ámbar , Animales , Insectos/clasificación , Mianmar
5.
Nanotechnology ; 28(46): 465302, 2017 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-29064823

RESUMEN

Stretchable electrodes are a critical component for flexible electronics such as displays, energy devices, and wearable sensors. Carbon nanotubes (CNTs) and graphene have been considered for flexible electrode applications, due to their mechanical strength, high carrier mobility, and excellent thermal conductivity. Vertically aligned carbon nanotubes (VACNTs) provide the possibility to serve as interconnects to graphene sheets as stretchable electrodes that could maintain high electrical conductivity under large tensile strain. In this work, a graphene oxide (GO)-VACNT hybrid on a PDMS substrate was demonstrated. Here, 50 µm long VACNTs were grown on a Si/SiO2 wafer substrate via atmospheric pressure chemical vapor deposition. VACNTs were directly transferred by delamination from the Si/SiO2 to a semi-cured PDMS substrate, ensuring strong adhesion between VACNTs and PDMS upon full curing of the PDMS. GO ink was then printed on the surface of the VACNT carpet and thermally reduced to reduced graphene oxide (rGO). The sheet resistance of the rGO-VACNT hybrid was measured under uniaxial tensile strains up to 300% applied to the substrate. Under applied strain, the rGO-VACNT hybrid maintained a sheet resistant of 386 ± 55 Ω/sq. Cyclic stretching of the rGO-VACNT hybrid was performed with up to 50 cycles at 100% maximum tensile strain, showing no increase in sheet resistance. These results demonstrate promising performance of the rGO-VACNT hybrid for flexible electronics applications.

7.
J Econ Entomol ; 108(4): 1915-22, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26470335

RESUMEN

The codling moth Cydia pomonella (L.) is a worldwide pest of pome fruit. A better understanding of oviposition site selection by this insect would help management of this pest in orchards. Oviposition site selection of codling moth was assessed by manipulative experiments and field survey. In addition, the temperatures of different sites were recorded. Neonate infestation and egg hatching were tested to evaluate the consequences of oviposition site selection. The percentage of eggs laid on the shady side of apple clusters was significantly higher than on the sunny side. How.ever, this was not influenced by leaf surface turning. Percentage of eggs on upper and lower leaf surfaces was significantly influenced by leaf surface turning. Percentage of eggs on the lower leaf surface was significantly higher than turned lower leaf surface (∼41.1% higher) and significantly higher (∼35.5%) on the turned upper leaf surface on than upper leaf surfaces. There was no significant difference in neonate infestation between leaves and fruit, as well as between the upper and lower leaf surfaces. Number of eggs hatching on the shady side of clusters was significantly higher than on the sunny side (56.3% higher). In both the manipulative experiment and field survey, codling moths did not choose the sites with the highest mean temperature, but chose sites suitable for egg development and hatching. This indicates that in the field codling moth, oviposition site selection is not strictly thermophilous, but they look for the lower leaf surface on the shady side, which benefits the offspring.


Asunto(s)
Mariposas Nocturnas/fisiología , Oviposición , Hojas de la Planta/fisiología , Animales , Femenino , Larva/fisiología , Malus/fisiología , Mariposas Nocturnas/crecimiento & desarrollo , Óvulo/crecimiento & desarrollo , Dinámica Poblacional , Temperatura
8.
J Econ Entomol ; 108(4): 1708-19, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26470312

RESUMEN

Accurate assessment of insect pest establishment risk is needed by national plant protection organizations to negotiate international trade of horticultural commodities that can potentially carry the pests and result in inadvertent introductions in the importing countries. We used mechanistic and correlative niche models to quantify and map the global patterns of the potential for establishment of codling moth (Cydia pomonella L.), a major pest of apples, peaches, pears, and other pome and stone fruits, and a quarantine pest in countries where it currently does not occur. The mechanistic model CLIMEX was calibrated using species-specific physiological tolerance thresholds, whereas the correlative model MaxEnt used species occurrences and climatic spatial data. Projected potential distribution from both models conformed well to the current known distribution of codling moth. None of the models predicted suitable environmental conditions in countries located between 20°N and 20°S potentially because of shorter photoperiod, and lack of chilling requirement (<60 d at ≤10°C) in these areas for codling moth to break diapause. Models predicted suitable conditions in South Korea and Japan where codling moth currently does not occur but where its preferred host species (i.e., apple) is present. Average annual temperature and latitude were the main environmental variables associated with codling moth distribution at global level. The predictive models developed in this study present the global risk of establishment of codling moth, and can be used for monitoring potential introductions of codling moth in different countries and by policy makers and trade negotiators in making science-based decisions.


Asunto(s)
Distribución Animal , Especies Introducidas , Mariposas Nocturnas/fisiología , Animales , Modelos Biológicos , Fotoperiodo , Temperatura
9.
Zookeys ; 1197: 153-169, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38651114

RESUMEN

The Chinese species of the highland weevil genus Pachynotus is revised, including a single known species, P.lampoglobus Chao & Y.-Q. Chen, 1980, and the descriptions of two new species, P.pilosussp. nov. and P.arcuatussp. nov. All Chinese Pachynotus species occur in Xizang (Tibet), China, and a key to these species is presented. Additionally, the COI sequences of two species, P.lampoglobus and P.pilosussp. nov., are provided, with details of the genetic distance.

10.
J Econ Entomol ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748467

RESUMEN

Biopesticides based on RNA interference (RNAi) took a major step forward with the first registration of a sprayable RNAi product, which targets the world's most damaging potato pest. Proactive resistance management is needed to delay the evolution of resistance by pests and sustain the efficacy of RNAi biopesticides.

11.
medRxiv ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38826360

RESUMEN

This hypothesis-generating study aims to examine the extent to which computed tomography-assessed body composition phenotypes are associated with immune and PI3K/AKT signaling pathways in breast tumors. A total of 52 patients with newly diagnosed breast cancer were classified into four body composition types: adequate (lowest two tertiles of total adipose tissue [TAT]) and highest two tertiles of total skeletal muscle [TSM] areas); high adiposity (highest tertile of TAT and highest two tertiles of TSM); low muscle (lowest tertile of TSM and lowest two tertiles of TAT); and high adiposity with low muscle (highest tertile of TAT and lowest tertile of TSM). Immune and PI3K/AKT pathway proteins were profiled in tumor epithelium and the leukocyte-enriched stromal microenvironment using GeoMx (NanoString). Linear mixed models were used to compare log2-transformed protein levels. Compared with the normal type, the low muscle type was associated with higher expression of INPP4B (log2-fold change = 1.14, p = 0.0003, false discovery rate = 0.028). Other significant associations included low muscle type with increased CTLA4 and decreased pan-AKT expression in tumor epithelium, and high adiposity with increased CD3, CD8, CD20, and CD45RO expression in stroma (P<0.05; false discovery rate >0.2). With confirmation, body composition can be associated with signaling pathways in distinct components of breast tumors, highlighting the potential utility of body composition in informing tumor biology and therapy efficacies.

12.
Zootaxa ; 3620: 533-43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26120723

RESUMEN

Xenysmoderodes Yoshitake, 2007, belonging to the tribe Mecysmoderini, was described as a monotypic genus from Japan, including the species X. sasajii Yoshitake. Two new species, X. concavius sp. nov. and X. flos sp. nov., are described here from China, providing a new country record for this genus. We revise the description of the genus based on three species and present an updated key to the species.


Asunto(s)
Gorgojos/anatomía & histología , Gorgojos/clasificación , Distribución Animal , Animales , China , Femenino , Masculino , Especificidad de la Especie , Gorgojos/fisiología
13.
Zootaxa ; 3619: 161-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26131472

RESUMEN

The Chinese representatives of the entimine weevil genus Geotragus are here revised, including redescriptions of the two previously known species, G. himalayanus Boheman, 1845 and G tuberculatus Chen, 1990, and descriptions of three new species from the Hengduan Mountains, Yunnan province, China: G. brevidens sp. nov., G. declivis sp. nov. and G. rugosus sp. nov.. Diagnostic characters of the genus, a key to Chinese species of Geotragus and a checklist of the now 11 known world species are also provided.


Asunto(s)
Gorgojos/anatomía & histología , Gorgojos/clasificación , Distribución Animal , Animales , China , Femenino , Masculino , Especificidad de la Especie , Gorgojos/fisiología
14.
Zootaxa ; 3652: 401-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26269843

RESUMEN

The genus Pelenomus Thomson from China is revised and six species are found occurring in China. Among them, P. curvatus, sp. nov. is described from Yunnan province, and four species are newly recorded from China: P waltoni (Boheman, 1843), P. canaliculatus (Fåhraeus, 1843), P. quadricorniger (Colonnelli, 1986) and P roelofsi (Hustache, 1916). Taxonomic diagnosis, habitus photos, detailed illustrations and distribution map of each species are provided, as well as a key to all the Chinese species. This study raised the number of Chinese Pelenomus from one to six species.


Asunto(s)
Escarabajos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , China , Escarabajos/anatomía & histología , Escarabajos/crecimiento & desarrollo , Femenino , Masculino , Tamaño de los Órganos
15.
Zootaxa ; 3750: 143-66, 2013 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-25113685

RESUMEN

The genus Rhinoncomimus Wagner, 1940 includes seven species from Eastern Asia. One new species, Rh. continuus sp. nov. from Yunnan, China, is described. Habitus photos, illustrations and descriptions of all species except Rh. rubripes Korotyaev, 2006 (a possible junior synonym of R. niger Chûjô and Morimoto, 1959) are provided in detail, as well as key to species and distribution maps. In addition, the host plant of the type species Rh. klapperichi Wagner, 1940, Polygonum hydropiper L. (Polygonaceae) is newly recorded.


Asunto(s)
Gorgojos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Animales , China , Ecosistema , Femenino , Masculino , Gorgojos/anatomía & histología
16.
bioRxiv ; 2023 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-37066143

RESUMEN

Background: As high-throughput studies advance, more and more high-dimensional multi-omics data are available and collected from the same patient cohort. Using multi-omics data as predictors to predict survival outcomes is challenging due to the complex structure of such data. Results: In this article, we introduce an adaptive sparse multi-block partial least square (asmbPLS) regression method by assigning different penalty factors to different blocks in different PLS components for feature selection and prediction. We compared the proposed method with several competitive algorithms in many aspects including prediction performance, feature selection and computation efficiency. The performance and the efficiency of our method were demonstrated using both the simulated and the real data. Conclusions: In summary, asmbPLS achieved a competitive performance in prediction, feature selection, and computation efficiency. We anticipate asmbPLS to be a valuable tool for multi-omics research. An R package called asmbPLS implementing this method is made publicly available on GitHub.

17.
Genes (Basel) ; 14(5)2023 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-37239321

RESUMEN

With the growing use of high-throughput technologies, multi-omics data containing various types of high-dimensional omics data is increasingly being generated to explore the association between the molecular mechanism of the host and diseases. In this study, we present an adaptive sparse multi-block partial least square discriminant analysis (asmbPLS-DA), an extension of our previous work, asmbPLS. This integrative approach identifies the most relevant features across different types of omics data while discriminating multiple disease outcome groups. We used simulation data with various scenarios and a real dataset from the TCGA project to demonstrate that asmbPLS-DA can identify key biomarkers from each type of omics data with better biological relevance than existing competitive methods. Moreover, asmbPLS-DA showed comparable performance in the classification of subjects in terms of disease status or phenotypes using integrated multi-omics molecular profiles, especially when combined with other classification algorithms, such as linear discriminant analysis and random forest. We have made the R package called asmbPLS that implements this method publicly available on GitHub. Overall, asmbPLS-DA achieved competitive performance in terms of feature selection and classification. We believe that asmbPLS-DA can be a valuable tool for multi-omics research.


Asunto(s)
Algoritmos , Multiómica , Biomarcadores , Simulación por Computador , Fenotipo
18.
Insects ; 14(1)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36662001

RESUMEN

Numerous studies have confirmed that the trade-off between anti-predator behavior and mating behavior occurs in certain insect species. This suggests that insects invest more in anti-predator behavior, and fewer resources or time can be used in mating behavior. However, few studies focus on tonic immobility, an important anti-predator behavior in nature, and different stages in mating behavior. Tonic immobility (TI) is considered to be an important anti-predator behavior. Herein, we investigated the relationship between TI and mating behavior in the sweetpotato weevil (SPW), Cylas formicarius. As the first step, we artificially selected SPWs for the longer duration of TI (L-strain) and the shorter duration of TI (S-strain). The effect of courtship and copulation on the duration of TI in two artificial selection strains was tested. Furthermore, we compared the frequency and duration of two mating behaviors in four kinds of pairs (LF×LM, LF×SM, SF×LM, and SF×SM: LM-L-strain male; SM-S-strain male; LF-L-strain female; SF-S-strain female). Finally, we tested insemination success in four kinds of pairs (male and female SPWs from the L-strain or the S-strain). The courtship and copulation significantly reduced the duration of TI. Pairs with males from the L-strain showed lower frequency and longer duration of courtship than pairs with males from the S-strain. Similarly, males from L-strain pairs showed a longer period of copulation than pairs with males from the S-strain. However, there is no significant difference in the frequency of copulation and the success of insemination. These results support that there was a significant trade-off between TI and courtship as well as copulation in the SPW.

19.
Insects ; 14(11)2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37999052

RESUMEN

The aphid, Aphis gossypii Glover, is identified as a significant pest that causes severe damage to goji berries in China. To analyze the ladybird consumption of aphids, the functional responses of three ladybird species, Harmonia axyridis, Coccinella septempunctata, and Hippodamia variegata, and intraspecific competition among ladybird individuals were evaluated under laboratory conditions. Moreover, the practical impact of ladybirds on aphid population reduction was investigated in semi-field conditions. We found that all adult ladybirds of the three species exhibited a type II functional response toward aphids. According to Holling's disc equation, H. axyridis exhibited the highest searching efficiency (a = 0.79), while C. septempunctata had the shortest handling time (Th = 5.07 min) among the three ladybird species studied. Additionally, intraspecific competition had a greater impact on H. variegata (m = 0.41) compared to the other two ladybird species. The semi-field study demonstrated that H. axyridis (83.9% reduction) and C. septempunctata (78.7% reduction) exhibited higher efficacy in reducing aphid populations compared to H. variegata (27.3% reduction). This study suggests that H. axyridis and C. septempunctata exhibit potential as effective biological control agents against aphids on goji berry plants and highlights the importance of considering intraspecific competition. However, the results obtained from laboratory and semi-field studies cannot be directly extrapolated to field conditions due to the simplification of these experimental systems. Future field studies are crucial in ensuring the effective implementation of a biological control program.

20.
Insects ; 15(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38249025

RESUMEN

The psyllid Bactericera gobica is a serious pest in goji berry orchards. The current primary psyllid control methods involve chemical pesticides, which pose potential risks to human health and the environment. The implementation and promotion of biological control agents should receive increased attention as an alternative approach to safeguarding goji berry orchards. To compare the predatory performance of three potential biocontrol agents of psyllids, including Harmonia axyridis, Coccinella septempunctata and Hippodamia variegata, the functional response and intraspecific interactions of adult ladybirds were studied under laboratory conditions. We observed a significantly higher searching efficiency (0.84 ± 0.09) in H. axyridis when preying on psyllids compared to H. variegata (0.55 ± 0.05), whereas the handling time for psyllids was considerably longer in H. axyridis (7.33 ± 0.83 min) than in H. variegata (5.67 ± 0.97 min). The impact of intraspecific interactions on H. variegata (0.44 ± 0.04) was significantly greater than that on C. septempunctata (0.29 ± 0.03), whereas the maximum consumption by C. septempunctata (223.35 ± 41.3) significantly exceeded that of H. variegata (133.4 ± 26.9). Our study suggests that each of these three ladybird species possesses distinct advantages as a potential predator of psyllids. However, further field studies are required to determine the most promising ladybird species for rapid impact through inundative biological control, taking into consideration the specific environmental adaptability of each ladybird species. The present study is expected to provide evidence that supports the potential of incorporating promising ladybird species as an effective biological control agent in goji berry orchard management programs.

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