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1.
Langmuir ; 40(25): 13219-13226, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38865155

RESUMO

Manipulating the motion of water droplets on surfaces, which is crucial for various applications, such as microfluidics and heat transfer, presents considerable challenges, primarily due to the significant influence of capillary forces. This effect becomes more pronounced when droplets are in close proximity, often resulting in undesired coalescence. Triboelectrification, which involves charging pure water droplets, is a promising approach to enhance the ability to manipulate water droplets. For effective triboelectrification, charges must accumulate within the droplets; this ensures efficient and sustained droplet manipulation while minimizing dissipation. Low-friction, superhydrophobic, insulating surfaces are ideal for this purpose. However, few studies have explored the application of insulating superhydrophobic surfaces to manipulate droplet motion. In this study, we investigated the behavior of water droplets on insulating superhydrophobic quartz surfaces after triboelectrification. The droplets acquired significant charge when dripped onto a superhydrophobic glass surface. Consequently, these charged droplets exhibited behaviors such as repulsion and acceleration from one another, uphill movement, and rapid long-distance transport to specific positions. These advancements in droplet manipulation techniques hold promise for diverse fields such as microfluidics and heat exchangers.

2.
Pestic Biochem Physiol ; 200: 105814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38582586

RESUMO

To explore active natural products against tobacco powdery mildew caused by Golovinomyces cichoracearum, an extract from the fermentation of endophytic Aspergillus fumigatus 0338 was investigated. The mechanisms of action for active compounds were also studied in detail. As a result, 14 indole alkaloid derivatives were isolated, with seven being newly discovered (1-7) and the remaining seven previously described (8-14). Notably, compounds 1-3 are rare linearly fused 6/6/5 tricyclic prenylated indole alkaloids, with asperversiamide J being the only known natural product of this kind. The isopentenyl substitutions at the 5-position in compounds 4 and 5 are also rare, with only compounds 1-(5-prenyl-1H-indol-3-yl)-propan-2-one (8) and 1-(6-methoxy-5-prenyl-1H-indol3-yl)-propan-2-one currently available. In addition, compounds 6 and 7 are new framework indole alkaloid derivatives bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. The purified compounds were evaluated for their activity against G. cichoracearum, and the results revealed that compounds 7 and 9 demonstrated obvious anti-G. cichoracearum activities with an inhibition rate of 82.6% and 85.2%, respectively, at a concentration of 250 µg/mL, these rates were better than that of the positive control agent, carbendazim (78.6%). The protective and curative effects of compounds 7 and 9 were also better than that of positive control, at the same concentration. Moreover, the mechanistic study showed that treatment with compound 9 significantly increased the structural tightness of tobacco leaves and directly affect the conidiospores of G. cichoracearum, thereby enhancing resistance. Compounds 7 and 9 could also induce systemic acquired resistance (SAR), directly regulating the expression of defense enzymes, defense genes, and plant semaphorins, which may further contribute to increased plant resistance. Based on the activity experiments and molecular dockings, the indole core structure may be the foundation of these compounds' anti-G. cichoracearum activity. Among them, the indole derivative parent structures of compounds 6, 7, and 9 exhibit strong effects. Moreover, the methoxy substitution in compound 7 can enhance their activity. By isolating and structurally identifying the above indole alkaloids, new candidates for anti-powdery mildew chemical screening were discovered, which could enhance the utilization of N. tabacum-derived fungi in pesticide development.


Assuntos
Alcaloides , Aspergillus fumigatus , Neopreno , Nicotiana , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/química , Alcaloides/farmacologia
3.
Pestic Biochem Physiol ; 196: 105613, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945230

RESUMO

In this study, seven novel anthraquinones (1-7) and four described anthraquinones (8-11) were purified from Nicotiana tabacum-derived Aspergillus oryzae YNCA1220. It is worth noting that only analogs of 4 and 5 have been reported as natural products to date, while the nuclei of compounds 1-3, 6 and 7 were isolated for the first time in nature. Among them, compounds 1-3 bear an unusual anthra[2,3-b]furan-9,10-dione nucleus, 4 and 5 possess a rare 3-methyl-1H-pyrrol-2-yl substituent, and 6 and 7 are new framework anthraquinones bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring. Interestingly, the in vivo assays indicated that 1, 4 and 5 had inactivation effects against tobacco mosaic virus (TMV) with inhibition rates of 41.6%, 55.4% and 38.6%, respectively, at a concentration of 50 µg/mL, which were better than that of the positive control agent, ningnanmycin (33.8%). Compounds 1, 4 and 5 also had protective effects with inhibition rates of 48.7%, 60.2% and 43.5% at the same concentration, while 4 had a better curative effect than ningnanmycin at a concentration of 100 µg/mL. In addition, mechanistic studies also revealed that a potent direct effect on TMV, the induction of SAR in tobacco plants, and the effective regulation of defense enzymes, defense genes, and defense hormones may be the reasons for the significant effects of 4 against TMV. At the same time, downregulation of the expression of total NtHsp70 protein by inhibiting the related Hsp70 genes may also be involved in tobacco resistance to TMV. To evaluate whether compounds have broader antiviral activities, the antirotavirus activities of new isolates were also evaluated and found to be highly effective with a therapeutic index (TI) value ranging from 11.6 to 17.7. This study suggests that the above anthraquinone compounds, particularly 4, have broad spectrum antiviral activities. The successful isolation and structure identification of the above anthraquinones provide new materials for the screening of anti-TMV agents and contribute to the improved utilization of N. tabacum-derived fungi.


Assuntos
Aspergillus oryzae , Vírus do Mosaico do Tabaco , Nicotiana , Antraquinonas/farmacologia , Bioensaio , Antivirais/farmacologia
4.
Int J Mol Sci ; 24(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37175410

RESUMO

Glioblastoma (GBM) is a malignant brain tumor, commonly treated with temozolomide (TMZ). Upregulation of A disintegrin and metalloproteinases (ADAMs) is correlated to malignancy; however, whether ADAMs modulate TMZ sensitivity in GBM cells remains unclear. To explore the role of ADAMs in TMZ resistance, we analyzed changes in ADAM expression following TMZ treatment using RNA sequencing and noted that ADAM17 was markedly upregulated. Hence, we established TMZ-resistant cell lines to elucidate the role of ADAM17. Furthermore, we evaluated the impact of ADAM17 knockdown on TMZ sensitivity in vitro and in vivo. Moreover, we predicted microRNAs upstream of ADAM17 and transfected miRNA mimics into cells to verify their effects on TMZ sensitivity. Additionally, the clinical significance of ADAM17 and miRNAs in GBM was analyzed. ADAM17 was upregulated in GBM cells under serum starvation and TMZ treatment and was overexpressed in TMZ-resistant cells. In in vitro and in vivo models, ADAM17 knockdown conferred greater TMZ sensitivity. miR-145 overexpression suppressed ADAM17 and sensitized cells to TMZ. ADAM17 upregulation and miR-145 downregulation in clinical specimens are associated with disease progression and poor prognosis. Thus, miR-145 enhances TMZ sensitivity by inhibiting ADAM17. These findings offer insights into the development of therapeutic approaches to overcome TMZ resistance.


Assuntos
Neoplasias Encefálicas , Glioblastoma , MicroRNAs , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Linhagem Celular Tumoral , MicroRNAs/metabolismo , Regulação para Baixo , Neoplasias Encefálicas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Proteína ADAM17/genética , Proteína ADAM17/metabolismo
5.
J Nurs Manag ; 30(7): 3093-3101, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35695219

RESUMO

AIM: To examine the role of demographic factors, mindfulness, and perceived stress on resilience among nurses. BACKGROUND: Resilience is an important attribute in the nursing profession although factors affecting it are very diverse. Knowing these factors may help in enhancing nurses' resilience and their subsequent quality healthcare delivery. METHOD: Utilizing a cross-sectional descriptive survey, a convenience sample was recruited to answer questions assessing resilience, perceived stress, and mindfulness in Taiwan between October and November 2021. Independent t-tests, one-way analyses of variance (ANOVAs) and hierarchical regression were used to analyse the data. RESULTS: A total of 816 nurses participated in the study. Postgraduate degree nurses had lower perceived stress (p = .006) and higher resilience (p = .003) compared with their college and undergraduate counterparts. Nurses working in internal medicine had significantly higher levels of perceived stress (p = .006) and lower levels of mindfulness (p = .005) compared with those in other departments. Single nurses had significantly higher levels of mindfulness (p = .04) but lower levels of resilience (p = .049) than those who were married. Educational level, perceived stress, and mindfulness were all factors that influenced nurses' resilience. CONCLUSION: Higher educational levels, perceived stress, and mindfulness appear to influence nurses' resilience. Nurses should therefore be encouraged to upgrade themselves academically, attend refresher courses, and learn adaptive coping strategies. IMPLICATIONS FOR NURSING MANAGEMENT: Hospital authorities should help nurses deal with stressful issues and offer career development opportunities to update, upgrade, and enhance their skillsets in the profession.


Assuntos
Atenção Plena , Enfermeiras e Enfermeiros , Humanos , Estudos Transversais , Adaptação Psicológica , Estresse Psicológico/complicações , Demografia , Inquéritos e Questionários
6.
Entropy (Basel) ; 24(9)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36141129

RESUMO

With the successful development in computer vision, building a deep convolutional neural network (CNNs) has been mainstream, considering the character of shared parameters in a convolutional layer. Stacking convolutional layers into a deep structure improves performance, but over-stacking also ramps up the needed resources for GPUs. Seeing another surge of Transformers in computer vision, the issue has aroused severely. A resource-hungry model is hardly implemented for limited hardware or single-customers-based GPU. Therefore, this work focuses on these concerns and proposes an efficient but robust backbone, which equips with channel and spatial direction attentions, so the attentions help to expand receptive fields in shallow convolutional layers and pass the information to every layer. An attention-boosted network based on already efficient CNNs, Universal Pixel Attention Networks (UPANets), is proposed. Through a series of experiments, UPANets fulfil the purposes of learning global information with less needed resources and outshine many existing SOTAs in CIFAR-{10, 100}.

7.
J Integr Plant Biol ; 62(2): 165-180, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30697931

RESUMO

Targeting-induced local lesions in genomes (TILLING) is a powerful reverse-genetics tool that enables high-throughput screening of genomic variations in plants. Although TILLING has been developed for many diploid plants, the technology has been used in very few polyploid species due to their genomic complexity. Here, we established an efficient capillary electrophoresis-based TILLING platform for allotetraploid cultivated tobacco (Nicotiana tabacum L.) using an ethyl methanesulfonate (EMS)-mutagenized population of 1,536 individuals. We optimized the procedures for endonuclease preparation, leaf tissue sampling, DNA extraction, normalization, pooling, PCR amplification, heteroduplex formation, and capillary electrophoresis. In a test screen using seven target genes with eight PCR fragments, we obtained 118 mutants. The mutation density was estimated to be approximately one mutation per 106 kb on average. Phenotypic analyses showed that mutations in two heavy metal transporter genes, HMA2S and HMA4T, led to reduced accumulation of cadmium and zinc, which was confirmed independently using CRISPR/Cas9 to generate knockout mutants. Our results demonstrate that this powerful TILLING platform (available at http://www.croptilling.org) can be used in tobacco to facilitate functional genomics applications.


Assuntos
Nicotiana/metabolismo , Sistemas CRISPR-Cas , Cádmio/metabolismo , Eletroforese Capilar , Metanossulfonato de Etila/metabolismo , Mutagênese/genética , Mutagênese/fisiologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Reação em Cadeia da Polimerase , Poliploidia , Nicotiana/genética , Zinco/metabolismo
8.
BMC Cancer ; 19(1): 756, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370819

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the most severe type of primary brain tumor with a high mortality rate. Although extensive treatments for GBM, including resection, irradiation, chemotherapy and immunotherapy, have been tried, the prognosis is still poor. Temozolomide (TMZ), an alkylating agent, is a front-line chemotherapeutic drug for the clinical treatment of GBM; however, its effects are very limited because of the chemoresistance. Valproic acid (VPA), an antiepileptic agent with histone deacetylase inhibitor activity, has been shown to have synergistic effects with TMZ against GBM. The mechanism of action of VPA on TMZ combination therapy is still unclear. Accumulating evidence has shown that secreted proteins are responsible for the cross talking among cells in the tumor microenvironment, which may play a critical role in the regulation of drug responses. METHODS: To understand the effect of VPA on secreted proteins in GBM cells, we first used the antibody array to analyze the cell culture supernatant from VPA-treated and untreated GBM cells. The results were further confirmed by lentivirus-mediated knockdown and exogenous recombinant administration. RESULTS: Our results showed that amphiregulin (AR) was highly secreted in VPA-treated cells. Knockdown of AR can sensitize GBM cells to TMZ. Furthermore, pretreatment of exogenous recombinant AR significantly increased EGFR activation and conferred resistance to TMZ. To further verify the effect of AR on TMZ resistance, cells pre-treated with AR neutralizing antibody markedly increased sensitivity to TMZ. In addition, we also observed that the expression of AR was positively correlated with the resistance of TMZ in different GBM cell lines. CONCLUSIONS: The present study aimed to identify the secreted proteins that contribute to the modulation of drug response. Understanding the full set of secreted proteins present in glial cells might help reveal potential therapeutic opportunities. The results indicated that AR may potentially serve as biomarker and therapeutic approach for chemotherapy regimens in GBM.


Assuntos
Anfirregulina/metabolismo , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Neuroglia/efeitos dos fármacos , Temozolomida/farmacologia , Ácido Valproico/farmacologia , Anfirregulina/genética , Anticorpos Bloqueadores/farmacologia , Biomarcadores Tumorais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Técnicas de Silenciamento de Genes , Humanos , Lentivirus/genética
9.
Mol Carcinog ; 57(12): 1816-1824, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30230033

RESUMO

Chondrosarcoma is characterized by the ability to produce extracellular matrix of cartilage. Curative surgical resection becomes difficult when high-grade chondrosarcoma metastasizes to other parts of the body. Doxorubicin (Dox) has been widely used clinically to treat many different types of cancers, including chondrosarcomas. However, chondrosarcoma is often resistant to chemotherapy and radiotherapy. New systemic treatment regimens are needed to improve the prognosis. Amphiregulin (AR) has been reported to be involved in cancer metastasis and drug resistance. The aim of the present study was to investigate the role of AR on cell migration and Dox sensitivity. To gain insight into the mechanisms used by AR to mediate its effects, we generated two chondrosarcoma cell lines, migration-prone JJ012 and Dox-resistant SW1353, to analyze the relationship between AR levels and cell functions. AR was highly expressed and secreted in mobile and drug-resistant cells. Next, we used the lentivirus-mediated RNAi system to knock down AR expression and found that AR silencing was significantly attenuated in cell migration and drug resistance. In addition, we used exogenous recombinant AR (r-AR) to confirm cell function and we introduced antibody array analysis to investigate pathways of AR activation. The results showed that AR can promote migratory activity and Dox resistance through activation of the MAPK pathway. Whereas the inhibition of the MAPK pathway has the potential to inhibit chondrosarcoma cell migration, p38 inhibition, and ERK activation may render cells more sensitive to Dox. These findings suggest that combining AR with MAPK blockade may effectively treat chondrosarcoma.


Assuntos
Anfirregulina/metabolismo , Neoplasias Ósseas/metabolismo , Condrossarcoma/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Ósseas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Condrossarcoma/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Sistema de Sinalização das MAP Quinases , Regulação para Cima
10.
Opt Express ; 26(26): 33756-33763, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650808

RESUMO

We report on the realization of a high-power, ultranarrow-linewidth, and frequency-locked 532 nm laser system. The laser system consists of single-pass and intra-cavity second harmonic generation of a continuous-wave Ytterbium doped fiber laser at 1064 nm in the nonlinear crystal of periodically poled lithium niobate and lithium triborate, respectively. With 47 W infrared input, 30 W green laser is generated through the type I critical phase matching in the intracavity lithium triborate crystal. The laser linewidth is measured to be on the order of sub-kHz, which is achieved by simultaneously locking the single-pass frequency doubling output onto the iodine absorption line R69 (36-1) at 532 nm. Furthermore, the phase locking between the laser system and another slave 1064 nm laser is demonstrated with relative frequency tunability being up to 10 GHz. Our results completely satisfy the requirements of 532 nm laser for quantum simulation with ultracold atoms.

11.
BMC Infect Dis ; 18(1): 402, 2018 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-30107826

RESUMO

BACKGROUND: Yersinia pestis is a contributing agent to the epidemic disease, plague, which killed an estimated 200 million people during historical times. In this study, a rapid, cheap, sensitive, and specific technique, the lateral flow assay (F1 strips), has been successfully developed to detect this pathogen, by using paired monoclonal antibodies (MAbs) against Y. pestis capsule like fraction 1 (F1) protein. Compared with the polyclonal antibody (PAb) based F1 strips, the Mab-based F1 strips have a remarkable increased detection limitation (10 to 100 folds). Furthermore, besides the limitation and specificity evaluation, the application of this F1 strip on simulated clinical samples indicate the LFA can be a good candidate to detect plague. METHODS: Recombinant F1 antigen was expressed and purified from a series of works. The various anti-F1 monoclonal antibodies generated from hybridoma cells were screened with the ELISA technique. To evaluate the feasibility of this Y. pestis F1 test strip, the F1 protein/Y. pestis was spiked into simulated clinical samples such as human serum, mouse bronchoalveolar lavage fluids, and mouse blood to mimic natural infection status. Additionally, this technique was applied to detect the Y. pestis in the environment-captured rats, to evaluate the practical usefulness of the strips. RESULTS: By using this MAb-based-LFA technique, 4 ng/ml of recombinant F1-protein and 103 CFU/ml of Y. pestis could be detected in less than 10 mins, which is at least 10-folds than that of the PAb format. On the other hand, although various Yersinia strains were applied to the strips, only Y. pestis strain showed a positive result; all other Yersinia species did not produce a positive signal, indicating the high efficiency and specificity of the MAb-based F1-strips. CONCLUSION: Based on our findings, we suggest that the MAb-format-LFA will be valuable as a diagnostic tool for the detection of Y. pestis. This report shows that the F1 strip is sufficient to support not only the detection of plague in simulated clinical samples, but also it may be a good candidate to meet the epidemiological surveillance during an outbreak of the biological warfare.


Assuntos
Proteínas de Bactérias/sangue , Imunoensaio/métodos , Yersinia pestis/isolamento & purificação , Animais , Anticorpos Monoclonais/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Líquido da Lavagem Broncoalveolar/microbiologia , Ouro/química , Humanos , Camundongos , Peste/diagnóstico , Peste/patologia , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Sensibilidade e Especificidade , Yersinia pestis/metabolismo
12.
Nature ; 488(7410): 185-8, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22874963

RESUMO

Transferring an unknown quantum state over arbitrary distances is essential for large-scale quantum communication and distributed quantum networks. It can be achieved with the help of long-distance quantum teleportation and entanglement distribution. The latter is also important for fundamental tests of the laws of quantum mechanics. Although quantum teleportation and entanglement distribution over moderate distances have been realized using optical fibre links, the huge photon loss and decoherence in fibres necessitate the use of quantum repeaters for larger distances. However, the practical realization of quantum repeaters remains experimentally challenging. Free-space channels, first used for quantum key distribution, offer a more promising approach because photon loss and decoherence are almost negligible in the atmosphere. Furthermore, by using satellites, ultra-long-distance quantum communication and tests of quantum foundations could be achieved on a global scale. Previous experiments have achieved free-space distribution of entangled photon pairs over distances of 600 metres (ref. 14) and 13 kilometres (ref. 15), and transfer of triggered single photons over a 144-kilometre one-link free-space channel. Most recently, following a modified scheme, free-space quantum teleportation over 16 kilometres was demonstrated with a single pair of entangled photons. Here we report quantum teleportation of independent qubits over a 97-kilometre one-link free-space channel with multi-photon entanglement. An average fidelity of 80.4 ± 0.9 per cent is achieved for six distinct states. Furthermore, we demonstrate entanglement distribution over a two-link channel, in which the entangled photons are separated by 101.8 kilometres. Violation of the Clauser-Horne-Shimony-Holt inequality is observed without the locality loophole. Besides being of fundamental interest, our results represent an important step towards a global quantum network. Moreover, the high-frequency and high-accuracy acquiring, pointing and tracking technique developed in our experiment can be directly used for future satellite-based quantum communication and large-scale tests of quantum foundations.

13.
Phys Rev Lett ; 117(14): 145301, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27740822

RESUMO

Quantized vortices play an essential role in diverse superfluid phenomena. In a Bose-Fermi superfluid mixture, especially of two mass-imbalance species, such macroscopic quantum phenomena are particularly rich due to the interplay between the Bose and Fermi superfluidity. However, generating a Bose-Fermi two-species superfluid, producing coupled vortex lattices within, and further probing interspecies interaction effects remain challenging. Here, we experimentally realize a two-species superfluid with dilute gases of lithium-6 and potassium-41, having a mass ratio of about seven. By rotating the superfluid mixture, we simultaneously produce coupled vortex lattices of the two species and thus present a definitive visual evidence for the double superfluidity. Moreover, we report several unconventional behaviors, due to the Bose-Fermi interaction, on the formation and decay of two-species vortices.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3326-31, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-30246979

RESUMO

The Indo-Pacific humpback dolphins (Sousa chinensis) with long life-span are top predators in marine ecosystem -and they could accumulate heavy metals and persistent organic pollutants in their tissues, while the melon is a unique lipid-rich structure within the cetacean forehead that functions in the transmission of echolocation signals. To explore the baseline levels and the main characteristics of the components, the concentrations of vanadium (V), nickel (Ni), chromium (Cr), manganese (Mn), copper (Cu), arsenic (As), zinc (Zn), mercury (Hg), selenium (Se), cadmium (Cd) and lead (Pb) were determined in the melon of the Indo-Pacific humpback dolphins with inductively coupled plasma mass spectrometry (ICP-MS). The results showed that this method was quite suitable for the determination of trace elements in the melon of Indo-Pacific humpback dolphins with highly accuracy and precision, and the trace elements in melon existed individual differences. The average contents were in the order of Zn>As>Cu>Mn>Se>Hg>Cr>Ni>V>Pb>Cd. It is worth noting that the within (1.158 µg·g-1 ww), non-essential toxic trace element may cause toxic effect on the dolphins. Spearman correlation analysis showed positively significant correlations between As, Cd, Hg and body length, indicating that the concentrations of As, Cd, Hg may increase with age. Moreover, Cr and Ni were positively correlated (p<0.05), a significant negative correlation was observed between Mn and As (p<0.01), indicating that there are certain correlation among elements. In addition, the principal component analysis results showed that V, Mn, Ni, Se, Cu, Hg are the main characteristics of trace elements for melon. This study presents a reliable method for determination of the trace element analysis in cetacean melon, and this is the first study that reports the trance elements in the melon of the Indo-Pacific humpback dolphins in PRE that could provide reasonable and effective information for its conservation work.


Assuntos
Golfinhos , Animais , Arsênio , Cobre , Cucurbitaceae , Ecossistema , Espectrometria de Massas , Mercúrio , Metais Pesados , Selênio , Oligoelementos
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2407-11, 2015 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-26669139

RESUMO

The liver, kidney and muscle samples from seven cetaceans were digested by microwave digestion, and trace elements amounts of V, Cd, Cu, Zn, As, Cr, Ni, Mn, Se, Hg and Pb were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the health risk assessment for Zn, Cu, Cd, Hg, Se in the liver was conducted. The results of international lobster hepatopancreas standard (TORT-2) showed acceptable agreement with the certified values, and the relative standard deviation (RSD) of eleven kinds of trace elements were less than 3.54%, showing that the method is suitable for the determination of trace elements in cetaceans. The experimental results indicated that different tissues and organs of the dolphins had different trace elements, presenting the tissue specificity. There is a certain inter-species difference among different dolphins about the bioaccumulation ability of the trace elements. The distribution of trace elements in whales presented a certain regularity: the contents of most elements in liver, kidney were much higher than the contents of muscle tissues, Cu, Mn, Hg, Se, and Zn exhibit the higher concentrations in liver, while Cd was mainly accumulated in kidney. And according to the health risk assessment in liver, the exceeding standardrate of selenium and copper in seven kinds of whales was 100%, suggesting that these whales were suffering the contamination of trace elements. The experimental results is instructive to the study of trace elements in cetaceans, while this is the first report for the concentrations in organs of Striped dolphin, Bottlenose dolphin, Fraser's Dolphin and Risso's dolphin in China, it may provide us valuable data for the conservation of cetaceans.


Assuntos
Cetáceos , Oligoelementos/análise , Animais , China , Cobre , Rim/química , Fígado/química , Espectrometria de Massas , Mercúrio , Micro-Ondas , Músculos/química , Medição de Risco , Selênio
16.
Nano Lett ; 13(10): 4715-20, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-24024651

RESUMO

To explore good anode materials of high safety, high reversible capacity, good cycling, and excellent rate capability, a Li3VO4 microbox with wall thickness of 40 nm was prepared by a one-pot and template-free in situ hydrothermal method. In addition, its composite with graphene nanosheets of about six layers of graphene was achieved. Both of them, especially the Li3VO4/graphene nanosheets composite, show superior electrochemical performance to the formerly reported vanadium-based anode materials. The composite shows a reversible capacity of 223 mAh g(-1) even at 20C (1C = 400 mAh g(-1)). After 500 cycles at 10C there is no evident capacity fading.

17.
Eur J Radiol ; 170: 111197, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992611

RESUMO

PURPOSE: To develop CT radiomics models of resectable esophageal squamous cell carcinoma (ESCC) and lymph node (LN) to preoperatively identify LN+. MATERIALS AND METHODS: 299 consecutive patients with ESCC were enrolled in the study, 140 of whom were LN+ and 159 were LN-. Of the 299 patients, 249 (from the same hospital) were randomly divided into a training cohort (n = 174) and a test cohort (n = 75). The remaining 50 patients, from a second hospital, were assigned to an external validation cohort. In the training cohort, preoperative contrast-enhanced CT radiomics features of ESCC and LN were extracted, then integrated with clinical features to develop three models: ESCC, LN and combined. The performance of these models was assessed using area under receiver operating characteristic curve (AUC), and F-1 score, which were validated in both the test cohort and external validation cohort. RESULTS: An ESCC model was developed for the training cohort utilizing the 8 tumor radiomics features, and an LN model was constructed using 9 nodal radiomics features. A combined model was constructed using both ESCC and LN extracted features, in addition to cT stage and LN+ distribution. This combined model had the highest predictive ability among the three models in the training cohort (AUC = 0.948, F1-score = 0.878). The predictive ability was validated in both the test and external validation cohorts (AUC = 0.885 and 0.867, F1-score = 0.816 and 0.773, respectively). CONCLUSION: To preoperatively determine LN+, the combined model is superior to models of ESCC and LN alone.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/cirurgia , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Radiômica , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Estudos Retrospectivos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia Computadorizada por Raios X
18.
Opt Express ; 21(22): 27260-8, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24216948

RESUMO

We report a free-space entanglement-based quantum key distribution experiment, implementing the biased basis protocol between two sites which are 15.3 km apart. Photon pairs from a polarization-entangled source are distributed through two 7.8-km free-space optical links. An optimal bias 20:80 between the X and Z basis is used. A post-processing scheme with finite-key analysis is applied to extract the final secure key. After three-hour continuous operation at night, a 4293-bit secure key is obtained, with a final key rate of 0.124 bit per raw key bit which increases the final key rate by 14.8% comparing to the standard BB84 case. Our results experimentally demonstrate that the efficient BB84 protocol, which increases key generation efficiency by biasing Alice and Bob's basis choices, is potentially useful for the ground-satellite quantum communication.

19.
Phys Rev Lett ; 110(26): 260407, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23848853

RESUMO

In their well-known paper, Einstein, Podolsky, and Rosen called the nonlocal correlation in quantum entanglement a "spooky action at a distance." If the spooky action does exist, what is its speed? All previous experiments along this direction have locality and freedom-of-choice loopholes. Here, we strictly closed the loopholes by observing a 12 h continuous violation of the Bell inequality and concluded that the lower bound speed of spooky action was 4 orders of magnitude of the speed of light if Earth's speed in any inertial reference frame was less than 10(-3) time the speed of light.

20.
Molecules ; 18(8): 9663-9, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23945641

RESUMO

Phytochemical investigations of the leaves of Garcinia paucinervis resulted in the isolation of three new xanthones 1-3 and five known analogues 4-8. Structural elucidations of 1-3 were performed by spectral methods such as 1D and 2D (HMQC, HMBC, and ROESY) NMR spectroscopy, in addition to high resolution mass spectrometry. Compounds 1-3 showed anti-TMV activities, with inhibition rates above 20%, especially for 1, which had a lower IC50 value of 21.4 µM.


Assuntos
Garcinia/química , Vírus do Mosaico do Tabaco/efeitos dos fármacos , Xantonas/isolamento & purificação , Xantonas/farmacologia , Antivirais/química , Antivirais/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Xantonas/química
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