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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32814014

RESUMEN

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Asunto(s)
Variación Genética/genética , Enfermedades por Picaduras de Garrapatas/microbiología , Garrapatas/genética , Animales , Línea Celular , Vectores de Enfermedades , Especificidad del Huésped/genética
2.
Opt Express ; 31(14): 23642-23650, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37475444

RESUMEN

Ultra-precise reflectors in the advanced light source facilities urgently call for local slope error measurements with nano-radian precision. However, the existing methods currently utilized in the long trace profiler systems struggle to meet the requirements. In this paper, we present a weak-value amplification enhanced absolute local slope measurement scheme, in which the surface height difference between two adjacent points can be measured directly with precision on the pico-meter level. As a result, the absolute local slope measurement reaches a record precision level of 9.7 nrad (RMS) with a small lateral separation of 0.5 mm. Comparing to the existing methods, our scheme is more disturbance-resistant, more compact and cost-effective. The local curvature measuring capability is also validated with two synchronously parallel local slope measurement paths, between which the separation is set as 2mm. A local curvature measurement is obtained with precision of 3.4 × 10-6m-1 (RMS) and its corresponding slope variation is 6.8 nrad. Our method exhibits important application prospects in the field of ultra-precise surface fabrication inspection.

3.
Connect Tissue Res ; 64(6): 569-578, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37550846

RESUMEN

PURPOSE: Ultrashort wave diathermy (USWD) is commonly used in diseases associated with osteoarticular and soft tissue injuries. However, while accelerating wound healing and preventing joint stiffness, there have been few reports on whether it leads to excessive hypertrophic scarring. The aim was to investigate the effects of different doses of USWD on hypertrophic scars. MATERIALS AND METHODS: A rabbit model of hypertrophic scars was used to determine which dose of USWD reduced scar hyperplasia. The scar thickness was calculated using Sirius red staining. All protein expression levels were determined by western blotting, including fibrosis, collagen deposition, and neoangiogenesis related proteins. Subsequently, flow cytometry and ELISAs were used to determine the proportions of macrophage and inflammatory levels. RESULTS: The wounds with USWD in histopathology showed the dermis was more markedly thickened in the 120 mA group, whereas the wounds with the 60 mA were less raised, comparing with the 0 mA; all detected protein levels were increased significantly, the 120 mA group comparing with the others, including heat shock, fibrosis, and neoangiogenesis, whereas the collagen deposition relative protein levels were decreased, the 60 mA group comparing with Sham group; Finally, in the proportion of macrophages and inflammatory levels the 120 mA group were the highest, and the group Sham was lower than group 60 mA. CONCLUSIONS: In hypertrophic scars, the 60 mA USWD could relieve scar formation and inflammatory reactions; however, higher doses could result in opposite consequences.


Asunto(s)
Cicatriz Hipertrófica , Traumatismos de los Tejidos Blandos , Animales , Conejos , Cicatriz Hipertrófica/metabolismo , Oído/patología , Colágeno/metabolismo , Cicatrización de Heridas , Traumatismos de los Tejidos Blandos/patología
4.
Epidemiol Infect ; 151: e174, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37675640

RESUMEN

Rodents and shrews are major reservoirs of various pathogens that are related to zoonotic infectious diseases. The purpose of this study was to investigate co-infections of zoonotic pathogens in rodents and shrews trapped in four provinces of China. We sampled different rodent and shrew communities within and around human settlements in four provinces of China and characterised several important zoonotic viral, bacterial, and parasitic pathogens by PCR methods and phylogenetic analysis. A total of 864 rodents and shrews belonging to 24 and 13 species from RODENTIA and EULIPOTYPHLA orders were captured, respectively. For viral pathogens, two species of hantavirus (Hantaan orthohantavirus and Caobang orthohantavirus) were identified in 3.47% of rodents and shrews. The overall prevalence of Bartonella spp., Anaplasmataceae, Babesia spp., Leptospira spp., Spotted fever group Rickettsiae, Borrelia spp., and Coxiella burnetii were 31.25%, 8.91%, 4.17%, 3.94%, 3.59%, 3.47%, and 0.58%, respectively. Furthermore, the highest co-infection status of three pathogens was observed among Bartonella spp., Leptospira spp., and Anaplasmataceae with a co-infection rate of 0.46%. Our results suggested that species distribution and co-infections of zoonotic pathogens were prevalent in rodents and shrews, highlighting the necessity of active surveillance for zoonotic pathogens in wild mammals in wider regions.


Asunto(s)
Bartonella , Coinfección , Leptospira , Animales , Bartonella/genética , China/epidemiología , Filogenia , Roedores/microbiología , Musarañas/microbiología
5.
Acta Pharmacol Sin ; 44(10): 2075-2090, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37344564

RESUMEN

Renal fibrosis is a common pathological feature of chronic kidney disease (CKD) with various etiologies, which seriously affects the structure and function of the kidney. Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily and plays a critical role in regulating the genes related to xenobiotic and endobiotic metabolism in mammals. Previous studies show that PXR is expressed in the kidney and has protective effect against acute kidney injury (AKI). In this study, we investigated the role of PXR in CKD. Adenine diet-induced CKD (AD) model was established in wild-type and PXR humanized (hPXR) mice, respectively, which were treated with pregnenolone-16α-carbonitrile (PCN, 50 mg/kg, twice a week for 4 weeks) or rifampicin (RIF, 10 mg·kg-1·d-1, for 4 weeks). We showed that both PCN and RIF, which activated mouse and human PXR, respectively, improved renal function and attenuated renal fibrosis in the two types of AD mice. In addition, PCN treatment also alleviated renal fibrosis in unilateral ureter obstruction (UUO) mice. On the contrary, PXR gene deficiency exacerbated renal dysfunction and fibrosis in both adenine- and UUO-induced CKD mice. We found that PCN treatment suppressed the expression of the profibrotic Wnt7a and ß-catenin in AD mice and in cultured mouse renal tubular epithelial cells treated with TGFß1 in vitro. We demonstrated that PXR was colocalized and interacted with p53 in the nuclei of tubular epithelial cells. Overexpression of p53 increased the expression of Wnt7a, ß-catenin and its downstream gene fibronectin. We further revealed that p53 bound to the promoter of Wnt7a gene to increase its transcription and ß-catenin activation, leading to increased expression of the downstream profibrotic genes, which was inhibited by PXR. Taken together, PXR activation alleviates renal fibrosis in mice via interacting with p53 and inhibiting the Wnt7a/ß-catenin signaling pathway.


Asunto(s)
Receptor X de Pregnano , Insuficiencia Renal Crónica , Vía de Señalización Wnt , Animales , Humanos , Ratones , beta Catenina/metabolismo , Fibrosis , Mamíferos/metabolismo , Receptor X de Pregnano/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/tratamiento farmacológico , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Rifampin/farmacología
6.
Biol Pharm Bull ; 46(7): 883-892, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37394639

RESUMEN

Ovarian cancer (OC) is one of the most common tumors in female reproductive organs with a five-year survival rate of less than 45%. Metastasis is a crucial contributor to OC development. ETS transcription factor (ELK3), as a transcriptional factor, have been involved in multiple tumor development. However, its role in OC remains elusive. In this study, we observed high expression of ELK3 and AEG1 in human OC tissues. OVCAR-3 and SKOV3 cells were treated with hypoxia to mimic tumor microenvironment in vivo. We found that the expression of ELK3 was significantly increased in cells under hypoxia compared with normoxia. ELK3 knockdown inhibited cell migration and invasion abilities under hypoxia. Moreover, ELK3 knockdown decreased ß-catenin expression and inhibited the activation of Wnt/ß-catenin pathway in SKOV3 cells under hypoxia. Astrocyte-elevated gene-1 (AEG1) has been reported to promote OC progression. Our results showed that the mRNA level of AEG1 was decreased when ELK3 knockdown under hypoxia. Dural luciferase assay confirmed that ELK3 bound to gene AEG1 promoter (-2005-+15) and enhanced its transcriptional activity under hypoxia. Overexpression of AEG1 increased the migration and invasion abilities of SKOV3 cell with ELK3 knockdown. In the absence of ELK3, the activation of ß-catenin was recovered by AEG1 overexpression. To sum up, we conclude that ELK3 promotes AEG1 expression by binding to its promoter. ELK3 could promote migration and invasion of OC cells by targeting AEG1, which provides a potential basis for therapeutic approaches to OC.


Asunto(s)
MicroARNs , Neoplasias Ováricas , Femenino , Humanos , Apoptosis , Astrocitos/patología , beta Catenina/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Hipoxia , MicroARNs/genética , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Microambiente Tumoral
7.
Molecules ; 28(11)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37298972

RESUMEN

Magnesium phosphate (MgP) has garnered growing interest in hard tissue replacement processes due to having similar biological characteristics to calcium phosphate (CaP). In this study, an MgP coating with the newberyite (MgHPO4·3H2O) was prepared on the surface of pure titanium (Ti) using the phosphate chemical conversion (PCC) method. The influence of reaction temperature on the phase composition, microstructure, and properties of coatings was systematically researched with the use of an X-ray diffractometer (XRD), a scanning electron microscope (SEM), a laser scanning confocal microscope (LSCM), a contact angle goniometer, and a tensile testing machine. The formation mechanism of MgP coating on Ti was also explored. In addition, the corrosion resistance of the coatings on Ti was researched by assessing the electrochemical behavior in 0.9% NaCl solution using an electrochemical workstation. The results showed that temperature did not obviously affect the phase composition of the MgP coatings, but affected the growth and nucleation of newberyite crystals. In addition, an increase in reaction temperature had a great impact on properties including surface roughness, thickness, bonding strength, and corrosion resistance. Higher reaction temperatures resulted in more continuous MgP, larger grain size, higher density, and better corrosion resistance.


Asunto(s)
Aleaciones , Titanio , Temperatura , Titanio/química , Aleaciones/química , Fosfatos/química , Corrosión , Propiedades de Superficie , Materiales Biocompatibles Revestidos/química
8.
Acta Pharmacol Sin ; 43(9): 2362-2372, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35105957

RESUMEN

Bile acid (BA) homeostasis is regulated by the extensive cross-talk between liver and intestine. Many bile-acid-activated signaling pathways have become attractive therapeutic targets for the treatment of metabolic disorders. In this study we investigated the regulatory mechanisms of BA in the intestine. We showed that the BA levels in the gallbladder and faeces were significantly increased, whereas serum BA levels decreased in systemic Krüppel-like factor 9 (Klf9) deficiency (Klf9-/-) mice. These phenotypes were also observed in the intestine-specific Klf9-deleted (Klf9vil-/-) mice. In contrast, BA levels in the gallbladder and faeces were reduced, whereas BA levels in the serum were increased in intestinal Klf9 transgenic (Klf9Rosa26+/+) mice. By using a combination of biochemical, molecular and functional assays, we revealed that Klf9 promoted the expression of apical sodium-dependent bile acid transporter (Asbt) in the terminal ileum to enhance BA absorption in the intestine. Reabsorbed BA affected liver BA synthetic enzymes by regulating Fgf15 expression. This study has identified a previously neglected transcriptional pathway that regulates BA homeostasis.


Asunto(s)
Ácidos y Sales Biliares , Factores de Transcripción de Tipo Kruppel/metabolismo , Simportadores , Animales , Ácidos y Sales Biliares/metabolismo , Circulación Enterohepática , Intestinos , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Simportadores/metabolismo , Factores de Transcripción/metabolismo
9.
Parasitol Res ; 121(8): 2347-2358, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35650429

RESUMEN

Ticks are deemed to be second only to mosquitoes as the most common vector of human infectious diseases worldwide that give rise to human and animal diseases and economic losses to livestock production. Our understanding of the phylogenetic analysis between tick lineages has been restricted by the phylogenetic markers of individual genes. Genomic data research could help advance our understanding of phylogenetic analysis and molecular evolution. Mitochondrial genomic DNA facilitated the phylogenetic analysis of eukaryotes containing ticks. In this study, we sequenced and assembled the circular complete mitogenome information of Ixodes granulatus. The 14,540-bp mitogenome consists of 37 genes, including 13 protein-coding genes (PCGs), two genes for ribosomal RNA (rRNAs), and 22 genes for transfer RNA (tRNAs), and the origin of the L-strand replication region. The directions of the coding strand and component genes in the non-Australasian Ixodes mitochondrial genome were similar to those found in most other Australasian Ixodes, except for the loss of a lengthy control region. The phylogenetic tree based on maximum likelihood (ML) and Bayesian inference (BI) computational algorithms showed that I. granulatus exhibits a close relationship with I. hexagonus and I. ricinus. To our knowledge, this is the first study exploring the complete mitogenome for the species I. granulatus. Our results provide new insights for further research on the evolution, population genetics, systematics, and molecular ecology of ticks.


Asunto(s)
Genoma Mitocondrial , Ixodes , Ixodidae , Animales , Teorema de Bayes , ADN Mitocondrial , Humanos , Ixodes/genética , Ixodidae/genética , Mosquitos Vectores , Filogenia , ARN Ribosómico/genética , ARN de Transferencia/genética
10.
Parasitol Res ; 121(7): 1951-1962, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35505098

RESUMEN

Ticks transmit diverse pathogens that cause human and animal diseases, leading to an increasing number of new challenges around the world. Genomic data research could help advance our learning of phylogenetic analysis and molecular evolution. Mitochondrial genome DNA has been helpful in illustrating the phylogenetic analysis of eukaryotes containing ticks. In this research, we sequenced and assembled the circular complete mitogenome information of Haemaphysalis kolonini. The 14,948-bp mitogenome consists of 37 genes which included 13 genes for protein-coding, two genes for ribosomal RNA, 22 genes for transfer RNA, and two control regions (D-loops). Overall, the composition and arrangement of genes were compared with Haemaphysalis ticks previously recorded in Genbank. The phylogenetic tree based on Maximum likelihood (ML) and Bayesian inference (BI) computational algorithms showed that H. kolonini has a close relationship with Haemaphysalis inermis. The complete mitogenome data provide a preferable perception to the phylogenetic relationship than the single-gene data analysis. To our knowledge, this is the first research exploring the complete mitogenome for the species H. kolonini. Our results provide new insights for further research on the evolution, population genetics, systematics, and molecular ecology of ticks.


Asunto(s)
Genoma Mitocondrial , Ixodidae , Garrapatas , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Ixodidae/genética , Filogenia , ARN Ribosómico/genética , Garrapatas/genética
11.
J Bioenerg Biomembr ; 53(2): 247-258, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33689096

RESUMEN

Pyrroline-5-carboxylate reductase 1 (PYCR1) plays a significant role in the malignant progression of various cancers. However, the role of PYCR1 in bladder cancer has not been well studied. This study was performed to evaluate the potential relevance of PYCR1 in bladder cancer. Our data revealed that PYCR1 expression was increased in bladder cancer tissues, and increased expression of PYCR1 was predictive of decreased survival rates. In bladder cancer cell lines, knockdown of PYCR1 caused significantly retarded cell growth and invasion, while PYCR1 overexpression accelerated cellular proliferation and invasion. Moreover, PYCR1 knockdown decreased levels of phosphorylated Akt, and enhanced activation of Wnt/ß-catenin signaling. Akt inhibition markedly abrogated of PYCR1 overexpression-mediated activation of Wnt/ß-catenin signaling. In addition, overexpression of ß-catenin partially reversed PYCR1 knockdown-mediated tumor suppression. Notably, PYCR1 knockdown significantly impeded tumor formation and growth in bladder cancer cells in vivo. In conclusion, these data demonstrate that PYCR1 is highly expressed in bladder cancer and knockdown of PYCR1 exerts a remarkable inhibitory effect on tumor formation via downregulation of Akt/Wnt/ß-catenin signaling. Our study suggests a potential role for PYCR1 in promoting bladder cancer progression and indicates that PYCR1 may be utilized as an attractive and promising anticancer target for treatment of bladder cancer.


Asunto(s)
Pirrolina Carboxilato Reductasas/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Animales , Femenino , Xenoinjertos , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , delta-1-Pirrolina-5-Carboxilato Reductasa
12.
BMC Pulm Med ; 21(1): 302, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34560863

RESUMEN

BACKGROUND: Pressurized metered dose inhalers (pMDIs) and dry powder inhalers (DPIs) are commonly used drug-delivering devices for patients with chronic airway diseases. Appropriate peak inhalation flow rate (PIFR) and inhaler technique is essential for effective therapy. We aimed at optimizing inhalation therapy through the analysis of PIFRs in patients with chronic obstructive pulmonary disease (COPD) or asthma as well as the effect of technique training using In-Check DIAL® to help patients to achieve their optimal inspiratory flow rates. METHODS: The study continuously enrolled patients who were diagnosed as COPD or asthma from respiratory clinics. PIFRs were described and analyzed between the newly-diagnosed and follow-up patients, and the stable and acute exacerbation patients, respectively. Every participant was trained inhaler technique using In-Check DIAL®. PIFRs before and after training was compared by self-control analysis. RESULTS: Among a total of 209 patients, the average age was 56.9 years. For DPIs users, 10.8% patients had a PIFR < 30 L/min and 44.1% patients had a PIFR ≥ 60 L/min before technique training. After technique training, scarcely patient (1.5%) had a PIFR < 30 L/min, and 60.5% patients had a PIFR ≥ 60 L/min. The patient's average PIFR increased by 5.6L/min after training. The increase in PIFR before and after training was significant (p < 0.001) for most patients, but no significant variation was found in patients with acute exacerbation (p = 0.822). CONCLUSIONS: A considerable number of patients with COPD or asthma were not able to achieve the minimum or optimal PIFR for DPIs. Inhaler training can increase patients' PIFRs and improve their ability to use DPIs. Trail registration The study has registered in chictr.org.cn (ChiCTR1900024707) and been approved by the Ethics Committee of Zhongshan Hospital of Fudan University (B2019-142).


Asunto(s)
Asma/tratamiento farmacológico , Inhaladores de Polvo Seco , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Terapia Respiratoria , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Estudios Prospectivos
13.
J Neuroeng Rehabil ; 18(1): 86, 2021 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-34030720

RESUMEN

BACKGROUND: Exoskeleton-assisted walking (EAW) is expected to improve the gait of spinal cord injury (SCI) individuals. However, few studies reported the changes of pulmonary function (PF) parameters after EAW trainings. Hence, we aimed to explore the effect of EAW on PF parameters, 6-min walk test (6MWT) and lower extremity motor score (LEMS) in individuals with SCI and to compare those with conventional trainings. METHODS: In this prospective, single-center, single-blinded randomized controlled pilot study, 18 SCI participants were randomized into the EAW group (n = 9) and conventional group (n = 9) and received 16 sessions of 50-60 min training (4 days/week, 4 weeks). Pulmonary function parameters consisting of the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), forced expiratory flow (FEF), peak expiratory flow, and maximal voluntary ventilation, 6MWT with assisted devices and LEMS were reported pre- and post-training. RESULTS: Values of FVC (p = 0.041), predicted FVC% (p = 0.012) and FEV1 (p = 0.013) were significantly greater in EAW group (FVC: 3.8 ± 1.1 L; FVC% pred = 94.1 ± 24.5%; FEV1: 3.5 ± 1.0 L) compared with conventional group (FVC: 2.8 ± 0.8 L; FVC% pred = 65.4 ± 17.6%; FEV1: 2.4 ± 0.6 L) after training. Participants in EAW group completed 6MWT with median 17.3 m while wearing the exoskeleton. There was no difference in LEMS and no adverse event. CONCLUSIONS: The current results suggest that EAW has potential benefits to facilitate PF parameters among individuals with lower thoracic neurological level of SCI compared with conventional trainings. Additionally, robotic exoskeleton helped walking. TRIAL REGISTRATION: Registered on 22 May 2020 at Chinese Clinical Trial Registry (ChiCTR2000033166). http://www.chictr.org.cn/edit.aspx?pid=53920&htm=4 .


Asunto(s)
Terapia por Ejercicio/instrumentación , Dispositivo Exoesqueleto , Resistencia Física/fisiología , Fenómenos Fisiológicos Respiratorios , Traumatismos de la Médula Espinal/rehabilitación , Adulto , Terapia por Ejercicio/métodos , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Pruebas de Función Respiratoria , Robótica , Método Simple Ciego , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/fisiopatología , Caminata
14.
Small ; 16(4): e1905700, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31885160

RESUMEN

Codoping of N and O in ultrathin graphitic carbon nitride (g-C3 N4 ) nanosheets leads to an inner electric field. This field restrains the recombination of photogenerated carriers and, thus, enhances hydrogen evolution. The layered structure of codoped g-C3 N4 nanosheets (N-O-CNNS) not only provides abundant sites of contact with the reaction medium, but also decreases the distance over which the photogenerated electron-hole pairs are transported to the reaction interface. Quantum confinement in the ultrathin structure results in an increased bandgap and makes the photocatalytic reaction more favorable than bulk g-C3 N4 . Under visible light irradiation, N-O-CNNS with 3 wt% Pt achieves a hydrogen evolution rate of 9.2 mmol g-1 h-1 and a value of 46.9 mmol g-1 h-1 under AM1.5 with 5 wt% Pt. Thus, this work paves the way for designing efficient nanostructures with increased separation/transfer efficiency of photogenerated carriers and, hence, increased photocatalytic activities.

15.
Phys Chem Chem Phys ; 22(8): 4453-4463, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32052825

RESUMEN

Amorphous carbon nitrogen (a-CN) has attracted a lot of attention due to its unique properties, different from those of its crystal form. Here, we demonstrate a near-infrared (NIR) photothermal conversion assisted photocatalytic hydrogen evolution from a-CN with nitrogen vacancies (a-CNN) nanosheets. Experiments suggest that sp2 hybridized C[double bond, length as m-dash]C structures can be created in a-CNN. These structures, just like small islands, disperse on a-CNN, leading to fluorescence quenching and a superior vis-NIR light absorption. Meanwhile, these structures, like "hot islands", can generate a stronger NIR photothermal conversion. A series of in situ characterization techniques are developed to clarify the detailed mechanism of photothermal conversion assisted photocatalytic hydrogen evolution. It is found that photothermal conversion can not only accelerate the drift velocity of the photo-induced carrier, but also increase the carrier concentration, which finally promotes the photocatalytic hydrogen evolution. Due to photothermal conversion assistance, the hydrogen production rate of a-CNN nanosheets is promoted to 3.1 mmol g-1 h-1 compared to 0.71 mmol g-1 h-1 for a-CN, in which the NIR photothermal conversion is proven to contribute a 16% promotion to the hydrogen production. These findings suggest that creating an NIR photothermal conversion of photocatalysts by constructing "hot islands" can greatly promote photocatalytic hydrogen production.

16.
Indoor Air ; 30(3): 422-432, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31883403

RESUMEN

The role of ventilation in preventing tuberculosis (TB) transmission has been widely proposed in infection control guidance. However, conclusive evidence is lacking. Modeling suggested the threshold of ventilation rate to reduce effective reproductive ratio (ratio between new secondary infectious cases and source cases) of TB to below 1 is corresponding to a carbon dioxide (CO2 ) level of 1000 parts per million (ppm). Here, we measured the effect of improving ventilation rate on a TB outbreak involving 27 TB cases and 1665 contacts in underventilated university buildings. Ventilation engineering decreased the maximum CO2 levels from 3204 ± 50 ppm to 591-603 ppm. Thereafter, the secondary attack rate of new contacts in university dropped to zero (mean follow-up duration: 5.9 years). Exposure to source TB cases under CO2 >1000 ppm indoor environment was a significant risk factor for contacts to become new infectious TB cases (P < .001). After adjusting for effects of contact investigation and latent TB infection treatment, improving ventilation rate to levels with CO2 <1000 ppm was independently associated with a 97% decrease (95% CI: 50%-99.9%) in the incidence of TB among contacts. These results show that maintaining adequate indoor ventilation could be a highly effective strategy for controlling TB outbreaks.


Asunto(s)
Tuberculosis/epidemiología , Ventilación , Adulto , Brotes de Enfermedades , Femenino , Humanos , Masculino , Tuberculosis/transmisión , Universidades
17.
Sensors (Basel) ; 20(7)2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32260068

RESUMEN

With the development of unmanned aerial vehicle (UAV) techniques, UAV images are becoming more widely used. However, as an essential step of UAV image application, the computation of stitching remains time intensive, especially for emergency applications. Addressing this issue, we propose a novel approach to use the position and pose information of UAV images to speed up the process of image stitching, called FUIS (fast UAV image stitching). This stitches images by feature points. However, unlike traditional approaches, our approach rapidly finds several anchor-matches instead of a lot of feature matches to stitch the image. Firstly, from a large number of feature points, we design a method to select a small number of them that are more helpful for stitching as anchor points. Then, a method is proposed to more quickly and accurately match these anchor points, using position and pose information. Experiments show that our method significantly reduces the time consumption compared with the-state-of-art approaches with accuracy guaranteed.

18.
Opt Express ; 27(5): 7344-7353, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30876299

RESUMEN

Multiple-path interference plays a fundamental role in classical and quantum physics. In this work, we propose two general schemes to realize multiple electromagnetically induced transparency (EIT) and electromagnetically induced absorption (EIA) in coupled microresonators and optomechanical systems. We give explicit physical descriptions and find out that these two schemes are essentially equivalent to each other. More importantly, we experimentally demonstrate both multiple EIT and EIA by coupling a microtoroid to a microsphere that supports multiple high Q optical modes with dense modes distributions. The theory fits well with the experimental results. We believe that our study and experimental results lay a foundation for realizing arbitrary multiple pathways interference in applications.

19.
Appl Opt ; 58(22): 6091-6097, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31503932

RESUMEN

Owing to its material properties, aluminum-based optical loads are widely used in the aerospace field. At present, the main processing of an aluminum alloy mirror is single-point diamond turning followed by the combined polishing process. The surface will generate some white crystals during the chemical mechanical polishing process (CMP). These crystals can affect the improvement of surface quality and seriously reduce the processing efficiency of the whole process. In view of the above problems, four main factors of crystallization are obtained by interface theoretical analysis, Visual MINTEQ simulation of chemical morphological distribution, and experimental analysis. They are temperature, PH value of polishing fluid, solid-liquid contact angle, and impurity content of aluminum alloy. The crystallization phenomenon in the polishing process is successfully suppressed by improving the polishing process and selecting new materials. The experimental results showed that the surface roughness decreased from 7.21 to 2.98 nm without crystallization using the new method.

20.
Phys Chem Chem Phys ; 19(21): 14178-14184, 2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28530305

RESUMEN

Photoelectrochemical water splitting holds great potential for solar energy conversion and storage with zero greenhouse gas emission. Integration of a suitable co-catalyst with an absorber material enables the realization of highly efficient photocleavage of water. Herein, nanostructured hematite film was coated with an ultrathin and conformal CoOx overlayer through atomic layer deposition (ALD). The best performing hybrid hematite with a 2-3 nm ALD CoOx overlayer yielded a remarkable turn on potential of 0.6 VRHE for the water oxidation reaction. Moreover, material analyses revealed that the surface amorphous CoOx/Co(OH)2 component exhibited good optical transparency and hydrophilic properties, which were beneficial for the formation of an ideal hematite/electrolyte interface. In addition to the presence of the CoOx overlayer, a negative shift of flat band potential (VFB) as well as suppression of surface recombination helped to significantly promote the charge separation and collection properties, contributing to the overall solar conversion efficiency. As a result, the external quantum efficiency (IPCE) obtained on hematite increases by 66% at 1.23 VRHE.

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