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1.
Sci Total Environ ; 925: 171664, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508278

RESUMO

Grapevine leafroll-associated virus 3 (GLRaV-3) is the most prevalent and economically damaging virus in grapevines and is found on nearly all continents, except Antarctica. Ten mealybugs act as vector insects transmitting the GLRaV-3. Understanding the potential distribution range of vector insects under climate change is crucial for preventing and managing vector insects and controlling and delaying the spread of GLRaV-3. This study investigated the potential geographical range of insect vectors of GLRaV-3 worldwide using MaxEnt (maximum entropy) based on occurrence data under environmental variables. The potential distributions of these insects were projected for the 2030s, 2050s, 2070s, and 2090s under the three climate change scenarios. The results showed that the potential distribution range of most vector insects is concentrated in Southeastern North America, Europe, Asia, and Southeast Australia. Most vector insects contract their potential distribution ranges under climate-change conditions. The stacked model suggested that potential distribution hotspots of vector insects were present in Southeastern North America, Europe, Southeast Asia, and Southeast Australia. The potential distribution range of hotspots would shrink with climate change. These results provide important information for governmental decision-makers and farmers in developing control and management strategies against vector insects of GLRaV-3. They can also serve as references for studies on other insect vectors.


Assuntos
Closteroviridae , Vitis , Animais , Doenças das Plantas , Insetos , Insetos Vetores
2.
Nanomaterials (Basel) ; 13(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38133031

RESUMO

Perovskites have been recognized as a class of promising materials for optoelectronic devices. We intentionally include excessive Cs+ cations in precursors in the synthesis of perovskite CsPbBr3 nanocrystals and investigate how the Cs+ cations influence the lattice strain in these perovskite nanocrystals. Upon light illumination, the lattice strain due to the addition of alkali metal Cs+ cations can be compensated by light-induced lattice expansion. When the Cs+ cation in precursors is about 10% excessive, the electron-phonon coupling strength can be reduced by about 70%, and the carrier cooling can be slowed down about 3.5 times in lead halide perovskite CsPbBr3 nanocrystals. This work reveals a new understanding of the role of Cs+ cations, which take the A-site in ABX3 perovskite and provide a new way to improve the performance of perovskites and their practical devices further.

3.
ACS Omega ; 6(10): 7157-7164, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748629

RESUMO

One recent development to improve optoelectronic properties of perovskites is to use a larger cation for multication engineering. The chain-like ethylammonium (EA) [(C2H5)NH3]+ cation is more likely to form a one-dimensional perovskite structure; however, there is no remarkable evidence in this connection. Therefore, in this work, for the first time, the EA cation as an alternative cation was introduced into FAPbBr3 cubic crystals to explore the stabilities and optoelectronic properties of mixed FA x EA(1-x)PbBr3 perovskites. The results indicate that replacing FA with EA is a more effective way to realize band gap tuning and morphology transformation between the cubic shape and microwires. The tuned band gap of perovskite is due to the variation of Pb-Br-Pb angles induced by the insertion of the larger EA cation. We highlight that this work provides new physical insights into the correlation between the engineering of organic cations and the formation of perovskite microwires and the tunable band gap. This observation will help us to find new ways to grow perovskite microwires and subsequently study the optoelectronic performance of low-dimensional perovskites devices.

4.
Onco Targets Ther ; 13: 8223-8232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32884300

RESUMO

BACKGROUND: New evidence suggests that histidine triad nucleotide-binding protein 1 (Hint1) exerts a tumor suppressor effect in various human tumors, such as colorectal cancer and gastric cancer. However, it has not been reported whether Hint1 is involved in the occurrence and development of osteosarcoma (OS). MATERIALS AND METHODS: The present study investigated the role of Hint1 in human OS cells by using cell lines, including 143B, U2OS, KHOS-240S, Saos-2 and MG-63. Cell proliferation and apoptosis were detected by flow cytometry. RESULTS: The present result revealed that Hint1 is downregulated in these cell lines. The overexpression of Hint1 by adenovirus transfection in 143B and MG63 cell lines suppressed the proliferation and cell cycle, and increased the cell apoptosis. Mechanically, it was found that Hint1 downregulated the cyclin D1 expression via FOXO1 inhibition. Furthermore, FOXO1 overexpression in the 143B and MG63 cell lines significantly blurred the effects of Hint1 on cellular proliferation and apoptosis. CONCLUSION: The present study indicates that Hint1 inhibits the development of OS by regulating FoxO1-cyclin D1, suggesting that Hint1 may be a new method for the treatment of OS.

5.
ACS Appl Mater Interfaces ; 12(4): 5081-5089, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31903740

RESUMO

In this work, the self-organized two-dimensional (2D) perovskite crystal sheet was synthesized for exciton-polariton studies. The layered 2D perovskite sheets naturally form Fabry-Pérot (F-P) optical cavities and exhibit evident cavity polariton modes. In the region of F-P cavity polariton modes, an exciton-polariton is formed by the superposition of strongly coupled exciton and photon states and the decreased spacing between two adjacent oscillation modes can be well explained by the formation of exciton polarities. Rabi splitting energy (Ω) evaluated from the energy-wavevector (E-k) dispersion relation of exciton-polariton coupling was about 259 ± 10 meV. For edge emissions of the laminated structure, the thickness-dependent quantum well exerts great influence on the band-gap absorption and emission. This work studies exciton-polariton properties in layered 2D perovskite sheets, making it possible application for polariton devices in the strong light-matter interaction region.

6.
ACS Appl Mater Interfaces ; 10(28): 24242-24248, 2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-29956540

RESUMO

A formamidinium (FA)-based perovskite is an ideal option for the potential efficient light-emitting diode (LED) in view of its high tolerance factor closer to 1. In this work, FA cation-based perovskite nanocrystals FA0.8Cs0.2Pb xBr3 ( x = 1.0, 0.8, 0.7, and 0.6) are fabricated with stoichiometric modification. The adoption of less-lead precursor is confirmed to be a feasible and effective approach in inhibiting nonradiative recombination by diminishing the presence of uncoordinated metallic Pb atoms. Note that the subsequent devices require the optimized lead ratio for an optimum behavior, a clear influence of Pb ratio on a perovskite LED has been established. No surprisingly, the less-lead perovskites exert positive roles on the perovskite LED performance, not only in terms of efficiency but also in stability. With an optimized composition FA0.8Cs0.2Pb0.7Br3, the perovskite LED displays the prominent performance with a current efficiency of 28.61 cd A-1, about 11-fold improvement than the previous best record of pure FA-based perovskite. Additionally, the perovskite device degradation can be mitigated under operating conditions by properly altering precursor stoichiometry, which can be attributed to the hydrogen reaction under moisture-induced ambient. The stoichiometric optimization of the metal Pb in the perovskite is an important strategy on the road to the further development of perovskite LEDs.

7.
Nanoscale ; 10(21): 9892-9898, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-29594286

RESUMO

Recently, lead halide perovskites have attracted significant scientific attention in the fields of photovoltaics, light emitting diodes, lasers, photo-detectors and other optoelectronic functional devices. The most stable crystal form of lead halide perovskites is the cube, including nano-cube and micro-cube, which hold great promise as functional materials due to their combination of unique optoelectronic properties and versatility through colloidal synthesis. Herein, we report the solution-processed synthesis of pure inorganic lead halide nano-cubes- and micro-cubes-based colloidal perovskites. The different size of cubes either into nano-cube or micro-cube are demonstrated that their phonon mode transformation which means the perovskite crystal structure phase change cross the nano-cube to micro-cube. The solution-processed colloidal synthesis method and phonon-mode transformation from nano-cube to micro-cube make pure inorganic lead halide perovskite an ideal platform for fundamental optoelectronic studies and the investigation of functional devices.

8.
Age Ageing ; 46(6): 957-964, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472415

RESUMO

Background: 'Frailty' is being increasing recognised as a geriatric syndrome of growing importance in the medical field. Acupressure is a non-pharmacological, non-invasive Traditional Chinese Medicine (TCM) treatment, which may serve to improve the quality of life (QOL) or prevent the progressive advancement of frailty in the aged population. Objective: to investigate the effects of a 12-week, TCM-principle guided acupressure intervention on the QOL of the frail older people living in the community. Methods: this is a randomised controlled trial with waitlist control design. Treatment group received 15 min of acupressure treatment, four times a week from both TCM practitioners and trained caregivers for 12 consecutive weeks. The waitlist control group served as a care-as-usual comparison to the treatment group for the 1st 12 weeks and then received the same treatment. Intention-to-treat principle was followed and mixed-effects models were used for data analysis. Results: the mean age of the participants was 76.12 ± 7.08, with a mean Tilburg frailty index score of 7.13 ± 1.76. Significant between-group differences were found in the change of physical domain score of WHOQOL-BREF (P = 0.001); change of Pittsburgh Sleep Quality Index (P < 0.001) and pain intensity (P = 0.006) with the treatment group demonstrating greater improvement. Within-group effect size analysis also indicated that the acupressure protocol has significant impact on these areas. Conclusions: the study's outcomes indicated that the acupressure protocol, when applied continuously for 12 weeks, 3-4 times a week, could improve the general QOL of frail older people living in community dwellings.


Assuntos
Acupressão/métodos , Fragilidade/terapia , Vida Independente , Pontos de Acupuntura , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/fisiopatologia , Fragilidade/psicologia , Avaliação Geriátrica , Hong Kong , Humanos , Masculino , Medição da Dor , Qualidade de Vida , Sono , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
9.
Artigo em Inglês | MEDLINE | ID: mdl-25103430

RESUMO

Although the brachyuran nature of Raninoidea is widely accepted, there is no consensus over the precise position of the Raninoidea within Brachyura. Long PCR and primer walking methods are employed to determine the first complete mitochondrial genome (mitogenome) sequence of raninoidian crab, Ranina ranina. It is a circular double-stranded DNA molecule of 15,563 base pairs (bp) in length with a standard set of 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), 13 protein-coding genes (PCGs) as well as a putative non-coding control region. The gene order is substantially consistent with that of the pancrustacean ground pattern with the tRNA(His) gene rearrangement. The basal placement of R. ranina in the phylogenetic tree integrated with a similar genomic organization to ancestral pancrustacea confirmed the primitive position of R. ranina in the Brachyura.


Assuntos
Braquiúros/genética , Genoma Mitocondrial , Animais , Composição de Bases , Sequência de Bases , Dados de Sequência Molecular , Fases de Leitura Aberta , RNA Ribossômico/genética , RNA de Transferência/genética
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 30(3): 481-5, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23865304

RESUMO

In order to research the infrared radiation characteristics of the skin covering Traditional Chinese acupuncture points, which are NeiGuan in the forearm and LaoGong in the center of the palm, we detected continuously the infrared radiation spectra of the human body surface by using Fourier Transform Infrared Spectroscopy. The experimental results showed that firstly, the differences of the infrared radiation spectra of the human body surface were obvious between individuals. Secondly, the infrared radiation intensity of the human body surface changed with time changing. The infrared radiation intensity in two special wavelength ranges (wavelengths from 6. 79 microm to 6. 85 microm and from 13. 6 microm to 14. 0 microm) changed much more than that in other ranges obviously. Thirdly, the proportions of the infrared radiation spectra changed, which were calculated from the spectra of two different aupuncture points, were same in these two special wavelength ranges, but their magnitude changes were different. These results suggested that the infrared radiation of acupuncture points have the same biological basis, and the mechanism of the infrared radiation in these two special wavelength ranges is different from other tissue heat radiation.


Assuntos
Pontos de Acupuntura , Raios Infravermelhos , Pele/efeitos da radiação , Adulto , Feminino , Humanos , Masculino , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Mar Genomics ; 6: 7-15, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22578654

RESUMO

As a phylogenetically valuable decapoda, a complete mitochondrial genome from Stenopodidea has not been reported to date. Here, we determined the complete mitochondrial DNA sequence of Stenopus hispidus (Olivier, 1811). The 15,528 bp genome is a circular molecule and consists of 13 protein-coding genes (PCGs) and two ribosomal RNA (rRNA) genes plus the putative control region (CR). This finding is similar to other metazoan animals but with the exception of 23 transfer RNA (tRNA) genes, which contain an additional tRNA-Gln compared with other crustaceans. With respect to the pancrustacean ground pattern mitochondria gene order, 5 tRNAs appear to be rearranged (tRNAs-Leu (CUN), Arg, Glu, Gln, and Met), one of which has also undergone inversion (tRNA-Leu (CUN)). Phylogenetic analyses reveal Stenopodidea and Reptantia form a clade sister to Caridea, which agrees with Abele and Felgenhauer's (1986) hypothesis. This topology contrasts with previous results based on morphological and some molecular data.


Assuntos
DNA Mitocondrial/química , Decápodes/genética , RNA de Transferência/genética , Animais , Composição de Bases , Sequência de Bases , Códon , DNA Mitocondrial/genética , Decápodes/classificação , Ordem dos Genes , Dados de Sequência Molecular , Filogenia , Proteínas/genética , RNA Ribossômico/genética , RNA de Transferência/química , Especificidade da Espécie , Translocação Genética
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