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1.
Int J Nanomedicine ; 19: 1909-1922, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38414522

RESUMEN

Background: Radionuclides have important roles in clinical tumor radiotherapy as they are used to kill tumor cells or as imaging agents for drug tracing. The application of radionuclides has been developing as an increasing number of nanomaterials are used to deliver radionuclides to tumor areas to kill tumor cells. However, promoting the efficient combination of radionuclides and nanocarriers (NCs), enhancing radionuclide loading efficiency, and avoiding environmental pollution caused by radionuclide overuse are important challenges that hinder their further development. Methods: In the present study, a new small molecule compound (3-[[(2S)-2-hydroxy-3-(4-hydroxyphenyl)-1-carbonyl] amino]-alanine, abbreviation: HN, molecular formula: C12H16N2O5) was synthesized as a linker between radionuclide iodine-125 (125I) and NCs to enable a more efficient binding between NCs and radionuclides. Results: In vitro evidence indicated that the linker was able to bind 125I with higher efficiency (labeling efficiency >80%) than that of tyrosine, as well as various NCs, such as cellulose nanofibers, metal oxide NCs, and graphene oxide. Single-photon emission computed tomography/computed tomography imaging demonstrated the biological distribution of 125I-labeled NCs in different organs/tissues after administration in mice. Conclusion: These results showed an improvement in radionuclide labeling efficiency for nanocarriers and provided an approach for nanocarrier image tracing.


Asunto(s)
Radioisótopos de Yodo , Neoplasias , Ratones , Animales , Radioisótopos de Yodo/química , Neoplasias/tratamiento farmacológico , Modelos Animales de Enfermedad , Tomografía Computarizada de Emisión de Fotón Único/métodos
2.
Sheng Wu Gong Cheng Xue Bao ; 40(2): 419-433, 2024 Feb 25.
Artículo en Chino | MEDLINE | ID: mdl-38369830

RESUMEN

Coronaviruses pose significant threats to animal and human health, leading to the development of various infectious diseases. It is critical to develop effective vaccines and antiviral medicines to prevent and treat these diseases. The coronavirus genome encodes several types of proteins, including structural, nonstructural, and accessory proteins. Among them, nonstructural protein 13 (NSP13) helicase plays a crucial role in regulating viral replication and the innate immune response of the host. Therefore, it serves as a vital target for the development of anti-coronavirus drugs. This paper presents a comprehensive review of NSP13 research, covering its source, structure, sequence conservation, unwinding mechanism, enzyme inhibitors, protein interaction, and immune regulation. Additionally, the paper analyzes the current challenges in NSP13 research and aims to provide a theoretical foundation for the development of broad-spectrum antiviral drugs targeting NSP13.


Asunto(s)
Infecciones por Coronavirus , Coronavirus , Animales , Humanos , ADN Helicasas/metabolismo , Proteínas no Estructurales Virales/genética , Replicación Viral , ARN Helicasas/genética , ARN Helicasas/metabolismo
3.
Poult Sci ; 103(3): 103397, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38295496

RESUMEN

Since 2011, the Gyrovirus galga 1 (GyVg1, previously recognized as avian gyrovirus 2) strain has extensively been detected worldwide. However, because there are no up-to-date reports of examining the distribution of GyVg1 in flocks in southern China, the epidemiology of this virus is unknown. To investigate the prevalence and genetic evolution of GyVg1, a total of 2,077 field samples collected from 113 chicken farms in 6 provinces in southern China during 2020 to 2022 were tested. Among them, 315 samples (315/2,077, 15.17%) were positive for GyVg1 by PCR. The positive rate of GyVg1 detection between different regions of southern China ranged from 11.69% (Guangdong) to 22.46% (Yunnan). The correlation between GyVg1 prevalence and sample source groups was analyzed, the results showing that the highest seroprevalence of GyVg1 was observed in visceral tissues (27.34%, 187/684), significantly higher (P < 0.05) than that of feather shafts (17.22%, 31/180), serums (8.85%, 78/881), and fecal (5.72%, 19/332). Additionally, the complete genomes of 10 GyVg1 strains were sequenced and analyzed, which showed nucleotide identities of 96.2 to 99.9%, 97.0 to 100.0%, 95.2 to 100.0%, and 95.7 to 99.8% in the complete genome, ORF1, ORF2, and ORF3, respectively, and 94.4 to 100.0%, 91.3 to 100.0%, and 98.7 to 100.0% amino acid similarity in the VP2, VP3, and VP1 proteins, respectively. Phylogenetic analysis of the whole genome showed that 10 GyVg1 strains belong to genotype I, and one strain belongs to genotype III. Sequence analysis showed several amino acid substitutions in both the VP1, VP2, and VP3 proteins. Our results enhance the understanding of the molecular characterization of GyVg1 infection in southern China. In conclusion, this study reveals the high prevalence and high genetic differentiation of GyVg1 in Chinese chickens and suggests that the potential impact of GyVg1 on the chicken industry may be of concern.


Asunto(s)
Gyrovirus , Animales , Gyrovirus/genética , Filogenia , Prevalencia , Estudios Seroepidemiológicos , Análisis de Secuencia de ADN/veterinaria , Pollos/genética , China/epidemiología
4.
Small Methods ; : e2301555, 2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38185747

RESUMEN

Iridium(III) complexes are particularly noted for their excellent potentials in fabrication of blue organic light-emitting diodes (OLEDs), but the severe efficiency roll-off largely hampered their practical applications. To reveal the underlying characteristics, three Ir(III) complexes, namely f-ct5c, f-ct5d, and f-ct11, bearing imidazo[4,5-b]pyrazin-2-ylidene cyclometalates are prepared and characterized in detail. Both f-ct5c and f-ct5d (also their mixture f-ct5mix) gave intensive blue emissions peaking at ≈465 nm with short radiative lifetimes of 1.76 and 2.45 µs respectively, in degassed toluene. Alternatively, f-ct11 with two 4-tert-butylphenyl substituents on each imidazo[4,5-b]pyrazin-2-ylidene entity, possessed a bluish-green emission (508 nm) together with an extended radiative lifetime of 34.3 µs in the dispersed PMMA matrix. Consequently, the resulting solution-processed OLED with f-ct11 delivered a maximum external quantum efficiency (EQEmax ) of 6.5% with serious efficiency roll-offs. In contrast, f-ct5mix based device achieved a high EQEmax of 27.2% and the EQE maintained at 23.0% of 1000 cd m-2 . Furthermore, the hyper-OLEDs with f-ct5mix as the sensitizer and v-DABNA as the terminal emitter afford narrowed emission with a considerably high EQEmax exceeding 32%, affirming the potential of f-ct5mix to serve as both the emitter and sensitizer in OLEDs.

5.
Poult Sci ; 103(2): 103264, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38035474

RESUMEN

In recent years, the infection rate of avian encephalomyelitis virus (AEV) infection in chickens has risen significantly, seriously endangering the development of the chicken industry. In order to study the current epidemiological status of AEV in China as well as the genetic and evolutionary patterns of the virus, we conducted a survey and genomic analysis of chicken AEV. The results showed that 46.26% (136/294) of the tissue samples tested (n = 294) were positive for AEV, with the highest positivity rate of 62.24% (61/98) among tissue samples from chickens aged 13 to 18 wk. The complete genomes of 2 representative AEV strains were determined, and the VP1 evolutionary tree results revealed that the 2 representative strains belonged to a novel AEV strain. Multiple alignment analysis showed that the ORF1 genes of the 2 representative strains differed by 82.3 to 99.9% at the amino acid level compared with the reference AEV strain, and the mutations at the key amino acid loci of VP2 and VP3 were the same as those in the chick embryo-adapted strain. The analysis makes up for the molecular epidemiological data and genetic variation of the 2 representative strains. The analysis makes up for the molecular epidemiological data and genetic variation of AEV and provides a basis for further understanding the spread of AEV in China.


Asunto(s)
Virus de la Encefalomielitis Aviar , Enfermedades de las Aves de Corral , Embrión de Pollo , Animales , Pollos , Virus de la Encefalomielitis Aviar/genética , Mutación , Aminoácidos , China/epidemiología , Enfermedades de las Aves de Corral/epidemiología
6.
Small ; : e2311114, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38157494

RESUMEN

Due to the relatively low photoluminescence quantum yield (PLQY) and horizontal dipole orientation of doped films, anthracene-based fluorescent organic light-emitting diodes (F-OLEDs) have faced a great challenge to achieve high external quantum efficiency (EQE). Herein, a novel approach is introduced by incorporating penta-helicene into anthracene, presented as linear-shaped 3-(4-(10-phenylanthracen-9-yl)phenyl)dibenzo[c,g]phenanthrene (BABH) and 3-(4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)dibenzo[c,g]phenanthrene (NABH). These blue hosts exhibit minimal intermolecular overlap of π-π stacking, effectively suppressing excimer formation, which facilitates the effective transfer of singlet energy to the fluorescent dopant for PLQY as high as 90%. Additionally, the as-obtained two hosts of BABH and NABH have effectively demonstrated major horizontal components transition dipole moments (TDM) and high thermal stability with glass transitional temperature (Tg ) surpassing 188 °C, enhancing the horizontal dipole orientation of their doped films to be 89% and 93%, respectively. The OLEDs based on BABH and NABH exhibit excellent EQE of 10.5% and 12.4% at 462 nm and device lifetime up to 90% of the initial luminance over 4500 h at 100 cd m-2 , which has firmly established them as among the most efficient blue F-OLEDs based on anthracene to date to the best knowledge. This work provides an instructive strategy to design an effective host for highly efficient and stable F-OLEDs.

7.
Small ; : e2307500, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37940631

RESUMEN

The promising cyclometalated iridium (III) complexes have been proved to possess great potential in vacuum-deposited organic light-emitting diodes (OLEDs) applications for full-color displays and white solid-state lighting sources. Herein, based on the unique bidentate ligand of dibenzo[a,c]phenazine (dbpz) group with strong conjugated effect of aromatic rings for red emission, four novel [3+2+1] coordinated iridium (III) emissive materials have been rationally designed and synthesized. The monodentate ligands of -CN and -OCN have been effectively employed to tune the deep-red emission of 628-675 nm with high photoluminescence quantum yields up to 98%. Moreover, all devices displayed deep-red color coordinates ranging from (0.675, 0.325) to (0.716, 0.284), which is close to the standard-red color coordinates of (0.708, 0.292), as recommended by International Telecommunication Union Radiocommunication (ITU-R) BT.2020. The device based on n BuIr(dbpz)CN with an exciplex cohost has exhibited maximum external quantum efficiencies of 20.7% and good stability. With n BuIr(dbpz)CN as an effective sensitizer, the n BuIr(dbpz)OCN based phosphorescent OLED devices have successfully demonstrated cascading energy transfer processes, contributing to pure red emission with maximum luminance as high as 6471 cd m-2 . Therefore, this work has been successfully demonstrated rational molecular design strategy of [3+2+1] iridium complexes to obtain highly efficient deep-red electrophosphorescent emission.

9.
BMC Vet Res ; 19(1): 232, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37936127

RESUMEN

BACKGROUND: Goose astrovirus (GoAstV) is an important pathogen that causes joint and visceral gout in goslings. It has been circulating in many provinces of China since 2017. Goose astrovirus genotypes 2 (GoAstV-2) is the main epidemic strain, and its high morbidity and mortality have caused huge economic losses to the goose industry. An accurate point-of-care detection for GoAstV-2 is of great significance. In this study, we developed a real-time reverse transcription recombinase polymerase amplification (RT-RPA) method for the on-site detection of GoAstV-2 infection. RESULTS: The real-time RT-RPA reaction was carried out at a constant temperature of 39 °C, and the entire detection time from nucleic acid preparation to the end of amplification was only 25 min using the portable device. The results of a specificity analysis showed that no cross-reaction was observed with other related pathogens. The detection limit of the assay was 100 RNA copies/µL. The low coefficient of variation value indicated excellent repeatability. We used 270 clinical samples to evaluate the performance of our established method, the positive concordance rates with RT-qPCR were 99.6%, and the linear regression analysis revealed a strong correlation. CONCLUSIONS: The established real-time RT-RPA assay showed high rapidity, specificity and sensitivity, which can be widely applied in the laboratory, field and especially in the resource-limited settings for GoAstV-2 point-of-care diagnosis.


Asunto(s)
Recombinasas , Transcripción Reversa , Animales , Recombinasas/metabolismo , Gansos , Sensibilidad y Especificidad , China , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Técnicas de Amplificación de Ácido Nucleico/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
10.
Adv Sci (Weinh) ; 10(29): e2301112, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37653609

RESUMEN

Two newly designed and synthesized [3+2+1] iridium complexes through introducing bulky trimethylsiliyl (TMS) groups are doped with a terminal emitter of v-DABNA to form an coincident overlapping spectra between the emission of these two phosphors and the absorption of v-DABNA, creating cascade resonant energy transfer for efficient triplet harvesting. To boost the color quality and efficiency, the fabricated hyper-OLEDs have been optimized to achieve a high external quantum efficiency of 31.06%, which has been among the highest efficiency results reported for phosphor sensitized saturated-blue hyper-OLEDs, and pure blue emission peak at 467 nm with the full width at half maxima (FWHM) as narrow as 18 nm and the CIEy values down to 0.097, satisfying the National Institute of Standards and Technology (NIST) requirement for saturated blue OLEDs display. Surprisingly, such hyper-OLEDs have obtained the converted lifetime (LT50 ) up to 4552 h at the brightness of 100 cd m-2 , demonstrating effective Förster resonance energy transfer (FRET) process. Therefore, employing these new bulky TMS substituent [3+2+1] iridium(III) complexes for effective sensitizers can greatly pave the way for further development of high efficiency and stable blue OLEDs in display and lighting applications.

11.
Sci Total Environ ; 904: 166662, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37657541

RESUMEN

Machine learning has been widely used for groundwater prediction. However, the hysteresis response of groundwater depth (GD) to input features has not been fully investigated. This study uses an interpretation method to reveal the interplay between climate, human activity, and GD while considering the response of groundwater to multiple factors. Six factors [precipitation (P), wind speed (WS), temperature (T), population (POP), gross domestic product (GDP), and effective irrigated area (EIA)] were selected to analyze the hysteresis response of GD in terms of the lag correlation coefficient and lag time. The correlation between climatic variables and GD was weaker than that of anthropogenic variables. The lag time between variables and different types of GD was less than four months at most sites, except for EIA and WS in deep groundwater. The SVM model achieved satisfactory performance in 89 % of the sites. If there were sharp changes in GD during the testing period or significant variations in its seasonal patterns at different times, the SVM model performed poorly. The model was interpreted using the Shapley additive explanation method. The impact of POP and GDP on deep groundwater in irrigated areas was higher than that of shallow groundwater. In urban areas with intensive human activities, anthropogenic variables were the main factors affecting shallow groundwater while the impact of climate was gradually increasing in the suburbs. The influence of precipitation on shallow groundwater was decreased after water transfer from the South-to-North Water Diversion project. Furthermore, this study proposed a multifactor-driven conceptual model that can provide recommendations for analyzing groundwater dynamics in similar areas.

12.
Microbiome ; 11(1): 155, 2023 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-37475003

RESUMEN

BACKGROUND: For more than a century, the Koch's postulates have been the golden rule for determining the causative agents in diseases. However, in cases of multiple pathogens-one disease, in which different pathogens can cause the same disease, the selection of microorganisms that regress infection is hard when Koch's postulates are applied. Microbiome approaches can obtain relatively complete information about disease-related microorganisms and can guide the selection of target microorganisms for regression infection. In the present study, whitish muscle syndrome (WMS) of Scylla paramamosain, which has typical symptoms with whitish muscle and blackened hemolymph was used as an example to establish a new research strategy that integrates microbiome approaches and Koch's postulates to determinate causative agents of multiple pathogens-one disease. RESULTS: Microbiome results revealed that Aeromonas, Acinetobacter, Shewanella, Chryseomicrobium, Exiguobacterium, Vibrio and Flavobacterium, and Kurtzmaniella in hemolymph were bacterial and fungal indicators for WMS. A total of 23 bacteria and 14 fungi were isolated from hemolymph and muscle tissues, and among the bacteria, Shewanella chilikensis, S. xiamenensis, Vibrio alginolyticus, S. putrefaciens, V. fluvialis, and V. parahaemolyticus were present in hemolymph and/or muscle tissues in each WMS crab, and the last three species were also present in three Healthy crabs. The target bacteria and fungi were further screened to regression infections based on two criteria: whether they belonged to the indicator genera for WMS, whether they were isolated from both hemolymph and muscle tissues in most WMS crabs. Only S. chilikensis, S. putrefaciens, S. xiamenensis, V. alginolyticus, V. fluvialis, and V. parahaemolyticus met both two criteria. The six bacteria that met both two criteria and six fungi and another bacterium that unmatched any of two criteria were used to perform regression infection experiments based on Koch's postulates. S. chilikensis, S. putrefaciens, S. xiamenensis, V. alginolyticus, V. fluvialis, and V. parahaemolyticus met both two criteria, and the results indicate that they cause WMS in crabs independently. CONCLUSIONS: This study fully demonstrated that our research strategy that integrates the microbiome and Koch's postulates can maximize the ability to catch pathogens in one net for the situation of multiple pathogens-one disease. Video Abstract.


Asunto(s)
Braquiuros , Microbiota , Vibrio , Animales , Braquiuros/microbiología , Músculos
13.
BMC Plant Biol ; 23(1): 302, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280509

RESUMEN

Heat stress poses a threat to plants in arid and semiarid regions, leading to soil salinization and plant mortality. Researchers are exploring remedies to alleviate these effects, including using gibberellic acid (GA3) to regulate plant enzymes and antioxidants. Additionally, sodium nitroprusside (SNP) is gaining attention, but its combined effect with GA3 requires further research. To address this gap, we investigated the effects of GA3 and SNP on plants under heat stress conditions. For that, wheat plants were cultivated under 40 °C for 6 h per day (15 days). Sodium nitroprusside (donor of NO and SNP) and gibberellic acid (GA3), respectively, with 100 µM and 5 µg/ml concentrations, were applied as foliar sprays at 10 days after sowing (DAS). Results showed that SNP + GA3 treatment had the highest plant height (4.48% increase), plant fresh weight (29.7%), plant dry weight (87%), photosynthetic rate (39.76%) and stomatal conductance (38.10%), and Rubisco (54.2%) compared to the control. Our findings indicate a significant increase in NO, H2O2, TBARS, SOD, POD, APX, proline, GR, and GB that greatly scavenged reactive oxygen species (ROS) for decreasing the adverse effect of stress. Such findings confirmed the efficacy of the combined treatment of SNP + GA3 under high-temperature stress compared to the solitary application of GA3, SNP, and control. In conclusion, using SNP + GA3 is a better strategy for mitigating heat stress in wheat than individual applications. Further research is recommended to validate the effectiveness of SNP + GA3 in other cereal crops.


Asunto(s)
Peróxido de Hidrógeno , Triticum , Nitroprusiato/farmacología , Triticum/fisiología , Peróxido de Hidrógeno/farmacología , Respuesta al Choque Térmico
14.
Poult Sci ; 102(8): 102830, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37343345

RESUMEN

Poultry is one of the most commonly farmed species and the most widespread meat industries. However, numerous poultry flocks have been long threatened by pathogenic bacterial infections, especially antimicrobial resistant pathogens. Here the prevalence and the antimicrobial resistance (AMR) profiles of bacterial pathogens isolated from poultry in Jiangxi Province, China were investigated. From 2020 to 2022, 283 tissue and liquid samples were collected from clinically diseased poultry, including duck, chicken, and goose, with an overall positive isolation rate of 62.90%. Among all the 219 bacterial isolates, 29 strains were gram-positive and 190 strains were gram-negative. Major bacteria species involved were avian pathogenic Escherichia coli (APEC; 57.53%; 126/219), followed by Salmonella spp. (11.87%, 26/219), Pasteurella multocida (6.39%, 14/219), and Staphylococcus spp. (1.22%, 11/219). Antimicrobial susceptibility testing showed the APEC isolates displayed considerably higher levels of AMR than the Salmonella and P. multocida isolates. The APEC isolates showed high resistance rate to amoxicillin (89.68%), ampicillin (89.68%), and florfenicol (83.33%), followed by streptomycin (75.40%), cefradine (65.87%), and enrofloxacin (64.29%). Multidrug-resistant isolates were observed in APEC (99.21%), Salmonella spp. (96.16%), and P. multocida (85.71%), and nearly 3 quarters of the APEC strains were resistant to 7 or more categories of antimicrobial drugs. Moreover, blaNDM genes associated with carbapenemase resistance and mcr-1 associated with colisitin resistance were detected in the APEC isolates. Our findings could provide evidence-based guidance for veterinarians to prevent and control bacterial diseases, and be helpful for monitoring the emerging and development of AMR in poultry bacterial pathogens.


Asunto(s)
Infecciones por Escherichia coli , Pasteurella multocida , Enfermedades de las Aves de Corral , Animales , Aves de Corral , Antibacterianos/farmacología , Pollos , Farmacorresistencia Bacteriana , Prevalencia , Escherichia coli , Infecciones por Escherichia coli/veterinaria , Salmonella , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología
15.
Poult Sci ; 102(7): 102730, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37167886

RESUMEN

The epidemic of goose astrovirus (GoAstV) caused huge losses to the poultry industry. Epidemiological studies in China revealed 2 circulating genotypes of GoAstV, but there is a lack of differential diagnosis tools. By analyzing all published genomes of GoAstV, this study designed specific PCR primers and Taqman probes to recognize different genotypes of GoAstV. After optimization and verification, this study developed a Taqman-based real-time quantitative PCR method that is capable of differential diagnosis. The established qPCR exhibited detection limitations of 100 copies/µL or 10 copies/µL, respectively, for GoAstV genotype 1 and genotype 2, and showed no false positive for other common avian viruses. This method was then used to analyze 72 samples collected from different regions in Jiangxi, and the results were verified by genome sequencing and phylogenetic analysis. These results revealed a complex coinfection of GoAstV different genotypes in China, highlighting the importance of long-term focus on the prevalence and genome evolution of GoAstV.


Asunto(s)
Avastrovirus , Gansos , Animales , Gansos/genética , Filogenia , Pollos/genética , Avastrovirus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Genotipo , Sensibilidad y Especificidad
16.
Adv Sci (Weinh) ; 10(12): e2207743, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36808857

RESUMEN

The 2D MoS2 with superior optoelectronic properties such as high charge mobility and broadband photoresponse has attracted broad research interests in photodetectors (PD). However, due to the atomic thin layer of 2D MoS2 , its pure photodetectors usually suffer from inevitable drawbacks such as large dark current, and intrinsically slow response time. Herein, a new organic material BTP-4F with high mobility is successfully stacked with 2D MoS2 film to form an integrated 2D MoS2 /organic P-N heterojunction, facilitating efficient charge transfer as well as significantly suppressed dark current. As a result, the as-obtained 2D MoS2 /organic (PD) has exhibited excellent response and fast response time of 332/274 µs. The analysis validated photogenerated electron transition from this monolayer MoS2 to subsequent BTP-4F film, whereas the transited electron is originated from the A- exciton of 2D MoS2 by temperature-dependent photoluminescent analysis. The ultrafast charge transfer time of ≈0.24 ps measured by time-resolved transient absorption spectrum is beneficial for efficient electron-hole pair separation, greatly contributing to the obtained fast photoresponse time of 332/274 µs. This work can open a promising window to acquire low-cost and high-speed (PD).

17.
Artículo en Inglés | MEDLINE | ID: mdl-36673923

RESUMEN

The implementation of carbon peaking and carbon neutrality is an essential measure to reduce greenhouse gas emissions and actively respond to climate change. The net carbon sink efficiency (NCSE), as an effective tool to measure the carbon budget capacity, is important in guiding the carbon emission reduction among cities and the maintenance of sustainable economic development. In this paper, NCSE values are used as a measure of the carbon budget capacity to measure the spatiotemporal evolution of the carbon neutral capacity of three major urban agglomerations (UAs) in China during 2007-2019. The clustering characteristics of the NCSE of these three major UAs, and various influencing factors such as carbon emissions, are analyzed using a spatiotemporal cube model and spatial and temporal series clustering. The results reveal the following. (1) From the overall perspective, the carbon emissions of the three major UAs mostly exhibited a fluctuating increasing trend and a general deficit during the study period. Moreover, the carbon sequestration showed a slightly decreasing trend, but not much fluctuation in general. (2) From the perspective of UAs, the cities in the Beijing-Tianjin-Hebei UA are dominated by low-low clustering in space and time; this clustering pattern is mainly concentrated in Beijing, Xingtai, Handan, and Langfang. The NCSE values in the Yangtze River Delta UA centered on Shanghai, Nanjing, and the surrounding cities exhibited high-high clustering in 2019, while Changzhou, Ningbo, and the surrounding cities exhibited low-high clustering. The NCSE values of the remaining cities in the Pearl River Delta UA, namely Guangzhou, Shenzhen, and Zhuhai, exhibited multi-cluster patterns that were not spatially and temporally significant, and the spatiotemporal clusters were found to be scattered. (3) In terms of the influencing factors, the NCSE of the Beijing-Tianjin-Hebei UA was found to be significantly influenced by the industrial structure and GDP per capita, that of the Yangtze River Delta UA was found to be significantly influenced by the industrial structure, and that of the Pearl River Delta UA was found to be significantly influenced by the population density and technology level. These findings can provide a reference and suggestions for the governments of different UAs to formulate differentiated carbon-neutral policies.


Asunto(s)
Secuestro de Carbono , Desarrollo Económico , Ciudades , China , Beijing , Ríos , Carbono/análisis
18.
Front Neurol ; 14: 1328896, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38187143

RESUMEN

Objective: To compare the repositioning effect of the modified Epley maneuver and the traditional Epley maneuver for posterior semicircular canal benign paroxysmal positional vertigo (PC-BPPV). Methods: Sixty-five patients with unilateral PC-BPPV were randomly divided into two groups. The control group received the traditional Epley maneuver, while the experimental group received the modified Epley maneuver, which prolonged the time in the healthy side lying position and the final bowing position. The number of successful repositions after one, two, and three attempts and the total number of successful repositions were recorded and compared between the two groups. A BPPV virtual simulation model was used to analyze the mechanism of the modified Epley maneuver. Results: The first repositioning success rate of the experimental group was significantly higher than that of the control group (85% vs. 63%, p = 0.040). The experimental group achieved 100% repositioning success rate after two attempts, while the control group needed three attempts to reach 86% repositioning success rate. Four cases in the control group experienced canal switching during the repositioning process, while none in the experimental group did. The BPPV virtual simulation model showed that the modified Epley maneuver could facilitate the passage of otoliths through the posterior arm of the posterior semicircular canal, especially through the location of obstruction. Conclusion: The modified Epley maneuver is more effective than the traditional Epley maneuver in improving the single repositioning success rate and reducing the canal switching rate for PC-BPPV. This study provides a new option for the treatment of BPPV.

19.
Front Cell Infect Microbiol ; 12: 938286, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36439226

RESUMEN

Streptococcus suis serotype 2 (SS2) is an important zoonotic pathogen that causes severe infections in humans and the swine industry. Acquisition and utilization of available carbon sources from challenging host environments is necessary for bacterial pathogens to ensure growth and proliferation. Glycogen is abundant in mammalian body and may support the growth of SS2 during infection in hosts. However, limited information is known about the mechanism between the glycogen utilization and host adaptation of SS2. Here, the pleiotropic effects of exogenous glycogen on SS2 were investigated through transcriptome sequencing. Analysis of transcriptome data showed that the main basic metabolic pathways, especially the core carbon metabolism pathways and virulence-associated factors, of SS2 responded actively to glycogen induction. Glycogen induction led to the perturbation of the glycolysis pathway and citrate cycle, but promoted the pentose phosphate pathway and carbohydrate transport systems. Extracellular glycogen utilization also promoted the mixed-acid fermentation in SS2 rather than homolactic fermentation. Subsequently, apuA, a gene encoding the unique bifunctional amylopullulanase for glycogen degradation, was deleted from the wild type and generated the mutant strain ΔapuA. The pathogenicity details of the wild type and ΔapuA cultured in glucose and glycogen were investigated and compared. Results revealed that the capsule synthesis or bacterial morphology were not affected by glycogen incubation or apuA deletion. However, extracellular glycogen utilization significantly enhanced the hemolytic activity, adhesion and invasion ability, and lethality of SS2. The deletion of apuA also impaired the pathogenicity of bacteria cultured in glucose, indicating that ApuA is indeed an important virulence factor. Our results revealed that exogenous glycogen utilization extensively influenced the expression profile of the S. suis genome. Based on the transcriptome response, exogenous glycogen utilization promoted the carbon adaption and pathogenicity of SS2.


Asunto(s)
Infecciones Estreptocócicas , Streptococcus suis , Humanos , Porcinos , Animales , Streptococcus suis/metabolismo , Virulencia/genética , Transcriptoma , Glucógeno/metabolismo , Serogrupo , Infecciones Estreptocócicas/microbiología , Factores de Virulencia/genética , Factores de Virulencia/metabolismo , Glucosa/metabolismo , Carbono/metabolismo , Mamíferos/genética
20.
Front Aging Neurosci ; 14: 976164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072479

RESUMEN

Background: Increased social distance is one of the manifestations of social impairment. Chronic low back pain (CLBP) is one of factors associated with increased social distance and social withdrawal. Exercise therapy is an effective means to social impairment. However, whether exercise could reduce social distance in patients with CLBP remains unknown. This study aimed to investigate the effect of exercise on social distance in middle-aged and elderly patients with CLBP. Methods: The longitudinal intervention recruited 29 middle-aged and elderly patients with CLBP from various communities in Yangpu District, Shanghai, China. The participants received exercise intervention for 8 weeks. The assessments were conducted before and after the intervention, including social distance, pain intensity, unpleasantness of pain, Roland-Morris Questionnaire (RMDQ), Self-Rating Anxiety Scale (SAS), and Self-Rating Depression Scale (SDS). Intention to treat analysis was performed. Results: After the 8-week exercise intervention, the social distance of patients with CLBP was shorter than that before intervention and showed significant difference (p < 0.05). The scores of pain intensity, unpleasantness of pain, RMDQ, SAS, and SDS also decreased and were significantly different between pre- and post-intervention (p < 0.05). In addition, the social distance, pain intensity, unpleasantness of pain, RMDQ, SAS, and SDS scores of the moderate CLBP group decreased more after the intervention compared with those of the mild CLBP group. Conclusion: The 8-week exercise intervention cannot only shorten the social distance in middle-aged and elderly patients with CLBP but also relieve pain, disability, and negative emotions.

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