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1.
Sensors (Basel) ; 22(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36080949

RESUMO

Red palm weevil (RPW) is a harmful pest that destroys many date, coconut, and oil palm plantations worldwide. It is not difficult to apply curative methods to trees infested with RPW; however, the early detection of RPW remains a major challenge, especially on large farms. In a controlled environment and an outdoor farm, we report on the integration of optical fiber distributed acoustic sensing (DAS) and machine learning (ML) for the early detection of true weevil larvae less than three weeks old. Specifically, temporal and spectral data recorded with the DAS system and processed by applying a 100-800 Hz filter are used to train convolutional neural network (CNN) models, which distinguish between "infested" and "healthy" signals with a classification accuracy of ∼97%. In addition, a strict ML-based classification approach is introduced to improve the false alarm performance metric of the system by ∼20%. In a controlled environment experiment, we find that the highest infestation alarm count of infested and healthy trees to be 1131 and 22, respectively, highlighting our system's ability to distinguish between the infested and healthy trees. On an outdoor farm, in contrast, the acoustic noise produced by wind is a major source of false alarm generation in our system. The best performance of our sensor is obtained when wind speeds are less than 9 mph. In a representative experiment, when wind speeds are less than 9 mph outdoor, the highest infestation alarm count of infested and healthy trees are recorded to be 1622 and 94, respectively.


Assuntos
Gorgulhos , Acústica , Animais , Larva , Redes Neurais de Computação , Fibras Ópticas
2.
Opt Express ; 30(3): 4231-4248, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35209664

RESUMO

We propose the asynchronous control of anisotropic diffusion (AD) algorithm, and such asynchronous anisotropic diffusion (AAD) algorithm is demonstrated experimentally to reduce noise from the sensing signals obtained from Brillouin distributed optical fiber sensors. The performance of the proposed AAD algorithm is analyzed in detail for different experimental conditions and compared with that of block-matching and 3D filtering, two-dimensional wavelet denoising, AD, and non-local means algorithms. Some key factors of the proposed algorithm, such as the impact of convolution kernel size on the performance of AD algorithms, the influence of low sampling point number (SPN) on the quality of Brillouin frequency shift and the selection of diffusion thresholds are analyzed and discussed with experimental results. The experimental results validate that the AAD algorithm can provide better root-mean-square error (RMSE) and spatial resolution (SR) than the other four algorithms, especially for higher signal-to-noise ratio (SNR) improvement and higher SPNs. For lower SPNs, the performance of AAD is also not inferior to the RMSE performance of NLM and AD. The runtime of the AAD algorithm is also quite low. Moreover, the proposed algorithm offers the best SR performance as compared to other noise reduction algorithms investigated in this study. Thus, the proposed AAD algorithm can be an effective candidate to improve the measurement accuracy of Brillouin distributed optical fiber sensors.

3.
Microbiol Spectr ; 9(2): e0018121, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-34668731

RESUMO

This study was conducted to determine the in vitro activities of gentamicin alone and in combination with ceftriaxone, ertapenem, and azithromycin against multidrug-resistant (MDR) Neisseria gonorrhoeae isolates. A total of 407 clinical isolates from Nanjing, China, obtained in 2016 to 2017, had MICs determined for gentamicin using the agar dilution method. MDR status was ascribed to 97 strains that displayed decreased susceptibility or resistance to extended-spectrum cephalosporins (ESCs) (ceftriaxone [MIC, ≥0.125 mg/liter] and cefixime [MIC, ≥0.25 mg/liter]), plus resistance to at least two of the following antimicrobials: penicillin (MIC, ≥2 mg/liter), ciprofloxacin (MIC, ≥1 mg/liter), and azithromycin (MIC, ≥1 mg/liter). MDR strains underwent MIC determinations for antimicrobial combinations using the antimicrobial gradient epsilometer test (Etest). Results that ranged from synergy to antagonism were interpreted using the fractional inhibitory concentration (FICI). All 407 gonococcal isolates were susceptible to gentamicin; MICs ranged from 2 mg/liter to 16 mg/liter. Synergy was demonstrated in 16.5% (16/97), 27.8% (27/97), and 8.2% (8/97) of MDR strains when gentamicin was combined with ceftriaxone (geometric mean [GM] FICI, 0.747), ertapenem (GM FICI, 0.662), and azithromycin (GM FICI, 1.021), respectively. No antimicrobial antagonism was observed with any combination tested against MDR strains; overall, antimicrobial combinations were indifferent. The GM MICs of gentamicin were reduced by 2.63-, 3.80-, and 1.98-fold when tested in combination with ceftriaxone, ertapenem, and azithromycin, respectively. The GM MICs of the three additional antimicrobials individually were reduced by 3-, 2.57-, and 1.98-fold, respectively, when each was tested in combination with gentamicin. Gentamicin alone was effective in vitro against N. gonorrhoeae, including MDR isolates. Combination testing of MDR strains showed lower MICs against gentamicin and each of three antimicrobials (ceftriaxone, ertapenem, and azithromycin) when used in combination. IMPORTANCE Antimicrobial-resistant Neisseria gonorrhoeae is a major global public health concern. New treatment options are urgently needed to successfully treat multidrug-resistant (MDR) Neisseria gonorrhoeae infections. This study showed that gentamicin maintained excellent in vitro susceptibility against clinical gonococcal isolates collected in 2016 and 2017, including MDR isolates. Combinations of gentamicin plus ertapenem, ceftriaxone, and azithromycin produced synergistic effects against certain MDR isolates. No antagonism was observed in any of the antimicrobial combinations, which may prove useful to guide clinical testing of combination therapies.


Assuntos
Antibacterianos/farmacologia , Azitromicina/farmacologia , Ceftriaxona/farmacologia , Ertapenem/farmacologia , Gentamicinas/farmacologia , Neisseria gonorrhoeae/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Sinergismo Farmacológico , Quimioterapia Combinada , Gonorreia/tratamento farmacológico , Gonorreia/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação
4.
Sensors (Basel) ; 21(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668776

RESUMO

Red palm weevil (RPW) is a detrimental pest, which has wiped out many palm tree farms worldwide. Early detection of RPW is challenging, especially in large-scale farms. Here, we introduce the combination of machine learning and fiber optic distributed acoustic sensing (DAS) techniques as a solution for the early detection of RPW in vast farms. Within the laboratory environment, we reconstructed the conditions of a farm that includes an infested tree with ∼12 day old weevil larvae and another healthy tree. Meanwhile, some noise sources are introduced, including wind and bird sounds around the trees. After training with the experimental time- and frequency-domain data provided by the fiber optic DAS system, a fully-connected artificial neural network (ANN) and a convolutional neural network (CNN) can efficiently recognize the healthy and infested trees with high classification accuracy values (99.9% by ANN with temporal data and 99.7% by CNN with spectral data, in reasonable noise conditions). This work paves the way for deploying the high efficiency and cost-effective fiber optic DAS to monitor RPW in open-air and large-scale farms containing thousands of trees.


Assuntos
Tecnologia de Fibra Óptica , Aprendizado de Máquina , Gorgulhos , Acústica , Animais , Larva
5.
Angew Chem Int Ed Engl ; 59(46): 20628-20635, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32725656

RESUMO

Inspired by the self-assembly of nanoparticle superlattices, we report a general method that exploits long-chain molecular ligands to induce ordered assembly of colloidal nanosheets (NSs), resulting in 2D laminate superlattices with high packing density. Co-assembly of two types of NSs further enables 2D/2D heterostructured superlattices. As a proof of concept, co-assembly of Ti3 C2 Tx and graphene oxide (GO) NSs followed by thermal annealing leads to MXene-rGO superlattices with tunable microstructures, which exhibit significantly higher capacitance than their filtrated counterparts, delivering an ultrahigh volumetric capacitance of 1443 F cm-3 at 2 mV s-1 . Moreover, the as-fabricated binder-free symmetric supercapacitors show a high volumetric energy density of 42.1 Wh L-1 , which is among the best reported for MXene-based materials in aqueous electrolytes. This work paves the way toward rational design of 2D material-based superstructures for energy applications.

6.
Opt Lett ; 45(11): 2969-2972, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32479435

RESUMO

An optical time-domain reflectometer (OTDR) is incapable of providing sensing or diagnostic information within dead-zones. We use a two-mode fiber (TMF) and a photonic lantern to completely overcome the main OTDR's dead-zone originating from the front facet of optical fiber. This is achieved by injecting the optical pulses of the OTDR in the form of the fundamental ${{\rm LP}_{{01}}}$ mode and meanwhile collecting the Rayleigh signals associated with the higher-order modes. Using the reported TMF-based OTDR, we accurately sense the position and frequency of a vibration event located within the dead-zone as a proof-of-concept demonstration.

7.
Sci Rep ; 10(1): 8402, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32439911

RESUMO

Although all wild-type bacterial populations exhibit antibiotic tolerance, bacterial mutants with higher or lower tolerant subpopulation sizes have been described. We recently showed that in mycobacteria, phenotypically-resistant subpopulations can grow in bulk-lethal concentrations of rifampicin, a first-line anti-tuberculous antibiotic targeting RNA polymerase. Phenotypic resistance was partly mediated by paradoxical upregulation of RNA polymerase in response to rifampicin. However, naturally occurring mutations that increase tolerance via this mechanism had not been previously described. Here, we used transposon insertional mutagenesis and deep sequencing (Tnseq) to investigate rifampicin-specific phenotypic resistance using two different in vitro models of rifampicin tolerance in Mycobacterium smegmatis. We identify multiple genetic factors that mediate susceptibility to rifampicin. Disruption of one gene, lepA, a translation-associated elongation factor, increased rifampicin tolerance in all experimental conditions. Deletion of lepA increased the subpopulation size that is able to grow in bulk-lethal rifampicin concentrations via upregulation of basal rpoB expression. Moreover, homologous mutations in lepA that are found in clinical Mycobacterium tuberculosis (Mtb) isolates phenocopy lepA deletion to varying degrees. Our study identifies multiple genetic factors associated with rifampicin tolerance in mycobacteria, and may allow correlation of genetic diversity of clinical Mtb isolates with clinically important phenotypes such as treatment regimen duration.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Mycobacterium smegmatis/efeitos dos fármacos , Mycobacterium smegmatis/genética , Fatores de Iniciação de Peptídeos/genética , Rifampina/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica , Humanos , Mutagênese , Mutação , Fenótipo , Tuberculose/microbiologia
8.
Environ Monit Assess ; 192(6): 370, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415432

RESUMO

The black soil region in Northeast China is an important production base of commodity grain. However, soil erosion is a major threat that has caused a decline in arable land area and productivity and a series of environmental problems in recent years. To understand the current situation of soil erosion and its changes in the whole black soil region, including six treatment regions, we used the spatial-temporal analysis of soil erosion from 2000 to 2015 and the overlay analysis with its drivers; additionally, soil erosion was evaluated qualitatively with the integrated evaluation method, and its change was indicated by the soil erosion change index (SECI). We found that soil erosion that caused soil loss occurred in each treatment region mainly at the light level in 2015. Water erosion, the most widely distributed erosion type, affected the largest area, while most serious erosion at intensive or higher levels stemmed from wind erosion. Although the situation of water erosion was improved in 2015 compared to that in 2000, the overall situation of soil erosion was worse due to the deterioration of wind and freeze-thaw erosion. Grassland, woodland, and cultivated land changes, such as the conversion from grassland to cultivated land, from woodland to sparse woodland and from dry land to paddy land, revealed these changes to a great extent.


Assuntos
Monitoramento Ambiental , Solo , China , Conservação dos Recursos Naturais , Florestas , Vento
9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(2): 553-557, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32319395

RESUMO

OBJECTIVE: To study the expression level and clinical significance of serum interleukin-6 (IL-6), its receptor (IL-6R) and myeloid cell leukemin-1(MCL-1) in patients with multiple myeloma(MM). METHODS: Ninety-eight cases of MM treated in our hospital from January 2014 to January 2019 were selected, and the patients were divided into three groups according to their DS stage: stage I (27 cases), stage II (34 cases) and stage III (37 cases). The expression levels of IL-6, IL-6R and MCL-1 in patients at different DS stages were compared, and the prognostic-related factors were analyzed. RESULTS: The expression levels of IL-6 and MCL-1 in patients rised with DS stages, and the difference showed statistical significance (P<0.05), but the level of IL-6R in three groups showed no significant difference (P>0.05). The prognosis of patients with different levels of IL-6 and MCL-1 was compared and the results were as follows, the median survival time of 41 patients with IL-6≥80 pg/ml was 33.0 months, and that of 57 patients with IL-6 <80 pg/ml was 33.5 months, which showed no significant difference (P>0.05). The median survival time of 45 patients with MCL-1≥200 pg/ml was 30.5 months, and that of 53 patients with MCL-1 <200 pg/ml was 37.0 months, and their difference was statistically significant (P<0.05). Sex, age, ß2-MG and Hb not significantly correlated with prognosis of patients (P>0.05), however, DS stage, IL-6 and MCL-1 correlated with prognosis of patients(r=2.261,r=1.754,r=1.905). CONCLUSION: The levels of IL-6 and MCL-1 in patients with multiple myeloma correlate with the DS stage and prognosis of patients.


Assuntos
Interleucina-6/metabolismo , Mieloma Múltiplo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Receptores de Interleucina-6/metabolismo , Humanos , Prognóstico , Transdução de Sinais
10.
Nanoscale ; 12(8): 5075-5083, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32068223

RESUMO

Fabricating lanthanide doped up-conversion luminescence based nanocomposites has drawn increasing attention in nanoscience and nanotechnology. Although challenging in precise synthesis, structure manipulation and interfacial engineering, fabricating dendritic mesoporous silica coated up-conversion nanoparticles (UCNP@dMSNs) with a tunable pore size is of great importance for the functionalization and application of UCNPs. Herein, we report a strategy to prepare uniform monodisperse UCNP@dMSNs with a core-shell structure. The silica shell has tunable center-radial and dendritic mesoporous channels. The synthesis was carried out in the heterogeneous oil-water microemulsion phase of the Winsor III system reaction system, which allows silica to be deposited directly on hydrophobic UCNPs through the self-anchoring of micelle complexes on the oleic acid ligand. The average pore size of UCNP@dMSNs could be tailored from ∼10 to ∼35 nm according to the varied amounts of co-solvent in the mixture. The microemulsion approach could also be used to prepare hierarchical UCNP@dMSNs with a multi-generational mesostructure. The resultant UCNP@dMSNs exhibit the unique advantage of loading "guest" nanoparticles in a self-absorption manner. We proved that Cu1.8S NPs (∼10 nm), Au NPs (∼10 nm) and Fe3O4 NPs (∼25 nm) could be incorporated in UCNP@dMSNs, which in turn validates the high adsorption capacity of UCNP@dMSNs.

11.
Opt Express ; 27(25): 36100-36113, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873396

RESUMO

In this paper, video block-matching and 3D filtering (VBM3D) denoising has been proposed and experimentally demonstrated for the first time in 100.8 km long-distance Brillouin optical time domain analyzer (BOTDA) sensing system with 2 m spatial resolution. Both experiments under static and slowly varying temperature environment are carried out. A temperature uncertainty of 0.43°C has been achieved with denoising by VBM3D in static temperature measurement. To our knowledge, this is one of the best temperature uncertainty reported for a sensing distance beyond 100 km. The slowly varying temperature at the end of 100.8 km fiber has also been accurately measured. VBM3D exploits both the spatial and temporal correlations of the data for denoising, thus it can significantly reduce the temperature fluctuations and keep the measured values close to the real temperature even if the temperature is temporally changing. We believe it would be useful for the long-distance sensing where the measurand may have temporal evolution in the slowly varying environment.

12.
Nano Converg ; 6(1): 4, 2019 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30710178

RESUMO

Recently, iron, nitrogen and sulfur codoped carbon-based materials have gained increasing attention for their synergistic effect towards superior electrocatalytic oxygen reduction performance. To gain insight into the contributions of the heteroatoms, we developed a facile and reproducible method for constructing Fe, N, S-codoped carbon frameworks derived from self-assembled Fe3O4 nanocrystal superlattices. The material constructed by the suggested method exhibited excellent ORR activity with more positive half-wave potential (∼ 0.869 V, vs RHE), higher diffusion-limiting current density (∼ 5.88 mA/cm2) and smaller Tafel slope (45 mV/dec) compared with Fe, N-codoped carbon frameworks and Pt/C. Notably, Fe3O4 nanocrystals served as both the building blocks for constructing carbon frameworks and the source of Fe residues leaving in the frameworks at the same time. By artificially tailoring the doping type and level as well as the homogeneousness of heteroatoms, the results discussed herein prove the importance of each kind of heteroatom in boosting ORR activity.

13.
Opt Express ; 27(3): 2530-2543, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732290

RESUMO

Simultaneous temperature and strain measurement with enhanced accuracy by using Deep Neural Networks (DNN) assisted Brillouin optical time domain analyzer (BOTDA) has been demonstrated. After trained by using combined ideal clean and noisy BGSs, the DNN is applied to extract both the temperature and strain directly from the measured double-peak BGS in large-effective-area fiber (LEAF). Both simulated and experimental data under different temperature and strain conditions have been used to verify the reliability of DNN-based simultaneous temperature and strain measurement, and demonstrate its advantages over BOTDA with the conventional equations solving method. Avoiding the small matrix determinant-induced large error, our DNN approach significantly improves the measurement accuracy. For a 24-km LEAF sensing fiber with a spatial resolution of 2m, the root mean square error (RMSE) and standard deviation (SD) of the measured temperature/strain by using DNN are improved to be 4.2°C/134.2µÎµ and 2.4°C/66.2µÎµ, respectively, which are much lower than the RMSE of 30.1°C/710.2µÎµ and SD of 19.4°C/529.1µÎµ for the conventional equations solving method. Moreover, the temperature and strain extraction by DNN from 600,000 BGSs along 24-km LEAF requires only 1.6s, which is much shorter than that of 5656.3s by the conventional equations solving method. The enhanced accuracy and fast processing speed make the DNN approach a practical way of achieving simultaneous temperature and strain measurement by the conventional BOTDA system without adding system complexity.

14.
Chem Commun (Camb) ; 55(9): 1229-1232, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30608074

RESUMO

Mesoporous FeS2@C superparticles chemically converted from Fe3O4 nanoparticle superlattices were used as anode materials for sodium-ion batteries with superior electrochemical performance. The partial etching of Fe3O4 nanoparticles creates appropriate void space, which is beneficial for confining the growth of ultrasmall FeS2 nanoparticles during sulfidation and for mitigating volume change of active materials during cycling.

15.
Nat Commun ; 9(1): 4218, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310059

RESUMO

Metrics commonly used to describe antibiotic efficacy rely on measurements performed on bacterial populations. However, certain cells in a bacterial population can continue to grow and divide, even at antibiotic concentrations that kill the majority of cells, in a phenomenon known as antibiotic tolerance. Here, we describe a form of semi-heritable tolerance to the key anti-mycobacterial agent rifampicin, which is known to inhibit transcription by targeting the ß subunit of the RNA polymerase (RpoB). We show that rifampicin exposure results in rpoB upregulation in a sub-population of cells, followed by growth. More specifically, rifampicin preferentially inhibits one of the two rpoB promoters (promoter I), allowing increased rpoB expression from a second promoter (promoter II), and thus triggering growth. Disruption of promoter architecture leads to differences in rifampicin susceptibility of the population, confirming the contribution of rifampicin-induced rpoB expression to tolerance.


Assuntos
Antibacterianos/farmacologia , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/genética , Rifampina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Sequência de Bases , RNA Polimerases Dirigidas por DNA/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Modelos Biológicos , Mycobacterium/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
16.
J Am Chem Soc ; 140(44): 15038-15047, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30359001

RESUMO

Self-assembled binary nanocrystal superlattices (BNSLs) represent an important class of solid-state materials with potentially designed properties. In pursuit of widening the range of applications for binary superlattice materials, it is desirable to develop scalable assembly methods that enable high-quality BNSLs with tailored compositions, structures, and morphologies. Here, we report the gram-scale assembly of crystalline binary nanocrystal superparticles with high phase purity through an emulsion-based process. The structure of the resulting BNSL colloids can be tuned in a wide range (AB13, AlB2, MgZn2, NaCl, and CaCu5) by varying the size and/or number ratios of the two nanocrystal components. Access to large-scale, phase-pure BNSL colloids offers vast opportunities for investigating their physiochemical properties, as exemplified by AB13-type CoFe2O4-Fe3O4 binary superparticles. Our results show that CoFe2O4-Fe3O4 binary superparticles not only display enhanced magnetic coupling but also exhibit superior lithium-storage properties. The nonclosed-packed NC packing arrangements of AB13-type binary superparticles are found to play a key role in facilitating lithiation/delithiation kinetics and maintaining structural integrity during repeated cycling. Our work establishes the scalable assembly of high-quality BNSL colloids, which is beneficial for accelerating the exploration of multicomponent nanocrystal superlattices toward various applications.

17.
Zhonghua Nan Ke Xue ; 24(12): 1073-1077, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-32212485

RESUMO

OBJECTIVE: To analyze Mycoplasma genitalium (MG) infection among the patients attending the clinic of sexually transmitted diseases (STD) in Nanjing. METHODS: Urethral and cervical swabs were collected from 2 753 patients (2 161 males and 592 females) who first sought medical care at our STD Clinic from November 2015 to December 2017. The patients ranged in age from 18 to 67 years (ï¼»37.55 ± 10.37ï¼½ yr), divided into six age groups: ≤20, 21-30, 31-40, 41-50, 51-60, and >60 yr. The samples were examined for MG infection by simultaneous amplification and testing, Chlamydia trachomatis (CT) by quantitative real-time PCR, Neisseria gonorrhoeae (NG), Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) with the Thayer-Martin medium, and the count of polymorphonuclear leukocytes (PMNL) by microscopy with Methylene blue stain. RESULTS: Among the 2 753 samples, 219 (7.95%), including 176 males (8.14%) and 43 females (7.26%), were found positive for MG, with no statistically significant differences between the male and female groups (χ2 = 0.492, P = 0.483). The MG infection rates in the male and female groups were 6.67% vs 12.12% in the ≤20-year-olds, 8.44% vs 8.64% in the 21-30-year-olds, 7.63% vs 6.19% in the 31-40-year-olds, 10% vs 4.72% in the 41-50-year-olds, 5.64% vs 0 in the 51-60-year-olds, and 8.33% vs 0 in the >60-year-olds, with no statistically significant differences among the age groups (χ2 = 4.76, P = 0.446), or in the males (χ2 = 7.240, P = 0.200) or females (χ2 = 6.718, P = 0.076). The incidence rate of MG simple infection was markedly higher in the males than in the females (62.30% ï¼»76/122ï¼½ vs 36.84% ï¼»14/38ï¼½, χ2 = 7.041, P < 0.01). MG infection was found in combination with one or more pathogens like NG, CT, UU and MH, with MG+UU as the most common co-infection (21.31% ï¼»26/122ï¼½ in males and 31.85% ï¼»12/38ï¼½ in females). Of the 76 male patients with MG simple infection, 30 (39.47%) had ≥5 PMNLs per high-power field, and 66 (86.84%) showed symptoms of urethritis. CONCLUSIONS: MG infection was found in both the symptomatic and asymptomatic patients attending the STD clinic in Nanjing, with no significant difference in the incidence rate between males and females. A higher rate of MG simple infection was observed in the males than in the females, most of the male patients with symptoms of urethritis and urethral PMNLs.


Assuntos
Infecções por Chlamydia , Infecções por Mycoplasma , Mycoplasma genitalium , Uretrite , Adolescente , Adulto , Idoso , Infecções por Chlamydia/complicações , Chlamydia trachomatis , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Mycoplasma/complicações , Mycoplasma genitalium/isolamento & purificação , Mycoplasma genitalium/patogenicidade , Mycoplasma hominis , Ureaplasma urealyticum , Uretrite/microbiologia , Adulto Jovem
18.
J Am Chem Soc ; 139(35): 12133-12136, 2017 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-28837323

RESUMO

Self-assembled nanocrystal (NC) superlattices are emerging as an important class of materials with rationally modulated properties. Engineering the nanoscale structure of constituent building blocks as well as the mesoscale morphology of NC superlattices is a crucial step in widening their range of applications. Here, we report a template-assisted epitaxial assembly strategy, enabling growth of freestanding, carbon-coated tubular monolayer superlattices (TMSLs). Specifically, we design and construct TMSLs of hollow Mn3O4 NCs (h-Mn3O4-TMSLs) by exploiting structural evolution of MnO NCs. The tubular superlattices obtained possess a number of unique and advantageous structural features unavailable in conventional NC superlattices, rendering them particularly attractive for energy conversion applications. We demonstrate this by employing h-Mn3O4-TMSLs as electrocatalysts for oxygen reduction, the catalytic performance of which is comparable to that of state-of-the-art Pt/C catalysts and superior to that of most manganese oxide-based catalysts reported.

19.
Nano Lett ; 17(3): 2003-2009, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28128964

RESUMO

Iron and nitrogen codoped carbons (Fe-N-C) have attracted increasingly greater attention as electrocatalysts for oxygen reduction reaction (ORR). Although challenging, the synthesis of Fe-N-C catalysts with highly dispersed and fully exposed active sites is of critical importance for improving the ORR activity. Here, we report a new type of graphitic Fe-N-C catalysts featuring numerous Fe single atoms anchored on a three-dimensional simple-cubic carbon framework. The Fe-N-C catalyst, derived from self-assembled Fe3O4 nanocube superlattices, was prepared by in situ ligand carbonization followed by acid etching and ammonia activation. Benefiting from its homogeneously dispersed and fully accessible active sites, highly graphitic nature, and enhanced mass transport, our Fe-N-C catalyst outperformed Pt/C and many previously reported Fe-N-C catalysts for ORR. Furthermore, when used for constructing the cathode for zinc-air batteries, our Fe-N-C catalyst exhibited current and power densities comparable to those of the state-of-the-art Pt/C catalyst.

20.
Toxicol Lett ; 265: 38-46, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27866976

RESUMO

The peroxisome proliferator-activated receptor gamma (PPAR-γ) is a ligand-activated nuclear receptor that regulates glucose and lipid metabolism. The aim of the present study was to investigate the effects of rosiglitazone (RSG), a synthetic PPAR-γ agonist, on acetaminophen (APAP)-induced acute liver injury. Male CD-1 mice were injected with APAP (300mg/kg). Some mice were pretreated with RSG (20mg/kg) 48, 24 and 1h before APAP injection. As expected, RSG pretreatment alleviated APAP-induced acute liver injury. Moreover, RSG pretreatment attenuated APAP-induced hepatic cell death and improved the survival. Although it did not affect hepatic cytochrome P450 (CYP)2E1 expression, RSG pretreatment attenuated reduction of hepatic glutathione peroxidase (GSH-Px), glutathione reductase (GSH-Rd) and glutathione S-transferase (GST) activities, inhibited upregulation of hepatic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX)-2 and NOX-4, and alleviated hepatic GSH depletion during APAP-induced acute liver injury. In addition, RSG pretreatment suppressed activation of hepatic nuclear factor kappa B (NF-κB) and extracellular signal-related kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling during APAP-induced acute liver injury. These results provide a novel mechanistic explanation for RSG-mediated protection against APAP-induced acute liver injury. The present results suggest that synthetic PPAR-γ agonists might be effective agents for preventing the progression of APAP-induced acute liver injury.


Assuntos
Acetaminofen/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/efeitos dos fármacos , NADPH Oxidases/genética , PPAR gama/agonistas , Tiazolidinedionas/uso terapêutico , Animais , Morte Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação para Baixo , Glutationa/metabolismo , Marcação In Situ das Extremidades Cortadas , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Fígado/imunologia , Fígado/patologia , Masculino , Camundongos Endogâmicos , Rosiglitazona , Tiazolidinedionas/administração & dosagem
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