Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
Appl Opt ; 63(12): 3130-3137, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856457

RESUMO

Numerous applications at the photon-starved regime require a free-space coupling single-photon detector with a large active area, low dark count rate (DCR), and superior time resolutions. Here, we developed a superconducting microstrip single-photon detector (SMSPD), with a large active area of 260 µm in diameter, a DCR of ∼5k c p s, and a low time jitter of ∼171p s, operated at a near-infrared of 1550 nm and a temperature of ∼2.0K. As a demonstration, we applied the detector to a single-pixel galvanometer scanning system and successfully reconstructed the object information in depth and intensity using a time-correlated photon counting technology.

2.
Plant Mol Biol ; 114(3): 37, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602592

RESUMO

Reactive oxygen species (ROS) is a chemically reactive chemical substance containing oxygen and a natural by-product of normal oxygen metabolism. Excessive ROS affect the growth process of crops, which will lead to the decrease of yield. Nitrogen, as a critical nutrient element in plants and plays a vital role in plant growth and crop production. Nitrate is the primary nitrogen source available to plants in agricultural soil and various natural environments. However, the molecular mechanism of ROS-nitrate crosstalk is still unclear. In this study, we used the foxtail millet (Setaria italica L.) as the material to figure it out. Here, we show that excessive NaCl inhibits nitrate-promoted plant growth and nitrogen use efficiency (NUE). NaCl induces ROS accumulation in roots, and ROS inhibits nitrate-induced gene expression in a short time. Surprisingly, low concentration ROS slight promotes and high concentration of ROS inhibits foxtail millet growth under long-term H2O2 treatment. These results may open a new perspective for further exploration of ROS-nitrate signaling pathway in plants.


Assuntos
Nitratos , Setaria (Planta) , Espécies Reativas de Oxigênio , Nitratos/farmacologia , Setaria (Planta)/genética , Peróxido de Hidrogênio , Cloreto de Sódio , Oxigênio , Transdução de Sinais , Perfilação da Expressão Gênica , Nitrogênio
3.
Nanomicro Lett ; 16(1): 173, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619642

RESUMO

With the diversified development of big data, detection and precision guidance technologies, electromagnetic (EM) functional materials and devices serving multiple spectrums have become a hot topic. Exploring the multispectral response of materials is a challenging and meaningful scientific question. In this study, MXene/TiO2 hybrids with tunable conduction loss and polarization relaxation are fabricated by in situ atomic reconstruction engineering. More importantly, MXene/TiO2 hybrids exhibit adjustable spectral responses in the GHz, infrared and visible spectrums, and several EM devices are constructed based on this. An antenna array provides excellent EM energy harvesting in multiple microwave bands, with |S11| up to - 63.2 dB, and can be tuned by the degree of bending. An ultra-wideband bandpass filter realizes a passband of about 5.4 GHz and effectively suppresses the transmission of EM signals in the stopband. An infrared stealth device has an emissivity of less than 0.2 in the infrared spectrum at wavelengths of 6-14 µm. This work can provide new inspiration for the design and development of multifunctional, multi-spectrum EM devices.

4.
Appl Opt ; 62(16): 4203-4212, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706905

RESUMO

We propose a method for coupling a tapered optical fiber to an inverted tapered SiN waveguide by fabricating a microfiber using 3D nanoprinting lithography. The microfiber consists of three parts: a tapered cladding cap, an S-bend, and a straight part, all composed of high-refractive-index material. Light is adiabatically coupled from the tapered fiber to the printed microfiber through the cladding cap. The light is then transmitted through the S-bend and the straight part with low loss and is finally coupled to the waveguide through the evanescent field. In the simulation, our design can achieve a high coupling efficiency (TE mode) of ∼97% at a wavelength of 1542 nm with a wide bandwidth of ∼768n m at the 1-dB cutoff criterion.

5.
Interdiscip Sci ; 15(4): 602-615, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37525066

RESUMO

Classification of glomerular pathology based on histology sections is the key to diagnose the type and degree of kidney diseases. To address problems in the classification of glomerular lesions in children, a deep learning-based complete glomerular classification framework was designed to detect and classify glomerular pathology. A neural network integrating Resnet and Senet (RS-INet) was proposed and a glomerular classification algorithm implemented to achieve high-precision classification of glomerular pathology. SE-Resnet was applied with improvement by transforming the convolutional layer of the original Resnet residual block into a convolutional block with smaller parameters as well as reduced network parameters on the premise of ensuring network performance. Experimental results showed that our algorithm had the best performance in differentiating mesangial proliferative glomerulonephritis (MsPGN), crescent glomerulonephritis (CGN), and glomerulosclerosis (GS) from normal glomerulus (Normal) compared with other classification algorithms. The accuracy rates were 0.960, 0.940, 0.937, and 0.968, respectively. This suggests that the classification algorithm proposed in the present study is able to identify glomerular lesions with a higher precision, and distinguish similar glomerular pathologies from each other.

6.
Opt Express ; 31(10): 16348-16360, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157715

RESUMO

The effective and convenient detection of single photons via advanced detectors with a large active area is becoming significant for quantum and classical applications. This work demonstrates the fabrication of a superconducting microstrip single-photon detector (SMSPD) with a millimeter-scale active area via the use of ultraviolet (UV) photolithography. The performances of NbN SMSPDs with different active areas and strip widths are characterized. SMSPDs fabricated by UV photolithography and electron beam lithography with small active areas are also compared from the aspects of the switching current density and line edge roughness. Furthermore, an SMSPD with an active area of 1 mm × 1 mm is obtained via UV photolithography, and during operation at 0.85 K, it exhibits near-saturated internal detection efficiency at wavelengths up to 800 nm. At a wavelength of 1550 nm, the detector exhibits a system detection efficiency of ∼5% (7%) and a timing jitter of 102 (144) ps, when illuminated with a light spot of ∼18 (600) µm in diameter, respectively.

7.
Zhongguo Gu Shang ; 34(3): 243-8, 2021 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-33787169

RESUMO

OBJECTIVE: To compared with the modified Robert Jones bandage of 3M elastic bandage, to evaluate the fitness, convenience, safety and comfort of the modular combination lower limb elastic compression device. METHODS: Forty healthy adult college students, including 28 males and 12 females, aged 16 to 25 (20.3±2.2) years old and weighing 40 to 81 (60.4±20.2) kg, were randomly divided into two groups with 40 samples in each group. According to the body surface parameters of Chinese lower limbs and guided by the concept of modularization, a group of modular combined lower limb elastic compression device was designed. Each module was combined to evaluate the fitness of the modular combined compression device in thelength and circumference of the lower limbs. The left and right lower limbs were randomly paired and divided into groups, with 40 samples in each group. The convenience of the operation time, adjustment times and required time were compared between two groups. The safety of the two groups after 24 hours of application of pressure injury was compared. The subjective pain feeling changes within 24 hours were recorded by visual analogue scale (VAS) to evaluate the comfort. RESULTS: The device was composed of several elastic compression outer lining modules with different length and width of 15 cm, an inner lining module for buffering, positioning and attaching the main body, and an elastic ankle compression module. The length of the elastic compression outer lining module covers the circumference of the human lower limbs. The length of a single outer lining module increased from 15 cm to 80 cm every 5 cm interval, and the length of a single inner lining module increased from 62 cm to 83 cm every 3 cm interval. After the modules were selected and combined, the length and circumference of the lower limbs can reach 100% fitness. The operation time of the first placement(118.23±7.33) s and re operation(60.08±5.88) s of experimental group were significantly shorter than those of control group (164.68±8.93) s and re operation (131.23±7.91) s. The adjustment times (3) and operation time (3.50±0.71) s of experimental group were significantly shorter than those of control group(11)and operation time(139.00±5.66) s (P<0.05), but there was no significant difference between two groups (P>0.05). The VAS score of experimental group was significantly lower than that of control group at each time point (P<0.01). CONCLUSION: The modular combined elastic compression device has good fitness, better placement and flexible adjustment, convenience and safety, and better comfort than modified Robert Jones bandage of 3M elastic bandage.


Assuntos
Bandagens Compressivas , Extremidade Inferior , Adolescente , Adulto , Feminino , Humanos , Masculino , Medição da Dor , Pressão , Resultado do Tratamento , Adulto Jovem
8.
Orthop Surg ; 12(3): 756-760, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32476289

RESUMO

OBJECTIVE: To evaluate the effect of cholecystectomy on the occurrence of knee osteoarthritis (KOA). METHODS: The present study was a case-control study with a retrospective, cross-sectional, and longitudinal study design. The clinical data for knee osteoarthritis in the Second Hospital of Shanxi Medical University from January 2016 to September 2018 was analyzed. Clinical data, including gender, age, height, weight, smoking, alcohol abuse, prior medical history, and previous surgical history, were recorded. A logistic regression model was used for the univariate and multivariate analysis. RESULTS: A total of 1659 patients with KOA (KOA group) and 1195 limb fracture patients (control group) were included in this study. Among the 1659 patients with KOA, 388 patients were male and 1271 were female, while among the 1195 patients in the control group, 638 patients were male and 557 patients were female. The period between cholecystectomy and knee osteoarthritis onset ranged from 0.5 years to 17 years; the average interval time was 8.73 ± 2.11 years. The age at disease onset was significantly older when compared to the control group, while the body mass index in the KOA group was significantly higher when compared to the control group (P < 0.05). There were 97 patients undergoing cholecystectomy in the KOA group and there were 15 patients undergoing cholecystectomy in the control group. The proportion of cholecystectomy in the two groups was statistically significant. After the univariate analysis, there was a statistically significant difference in distribution between the two groups (P < 0.05). The multivariate logistic regression analysis revealed that there was a significant difference in the distribution of these two groups (P < 0.05), indicating that cholecystectomy is associated with the occurrence of KOA. CONCLUSION: There is a close relationship between cholecystectomy and KOA. However, the specific mechanism remains unknown and should be further researched.


Assuntos
Colecistectomia , Osteoartrite do Joelho/epidemiologia , Idoso , Estudos de Casos e Controles , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Eur Radiol ; 29(3): 1607-1615, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30255258

RESUMO

OBJECTIVE: To quantitatively compare the diagnostic values of various diffusion parameters obtained from mono- and biexponential diffusion-weighted imaging (DWI) models and diffusion kurtosis imaging (DKI) in differentiating between benign and malignant solitary pulmonary lesions (SPLs). METHODS: Multiple b-value DWIs and DKIs were performed in 89 patients with SPL by using a 3-T magnetic resonance (MR) imaging unit. The apparent diffusion coefficient (ADC) of various b-value sets, true diffusivity (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), apparent diffusional kurtosis (Kapp), and kurtosis-corrected diffusion coefficient (Dapp) were calculated and compared between the malignant and benign groups using a Mann-Whitney U test. Receiver-operating characteristic analysis was performed for all parameters. RESULT: The ADC(0, 150) values of malignant tumors were lower than those of the benign group (p = 0.01). The ADC(0, 300), ADC(0, 500), ADC(0, 600), ADC(0, 800), ADC(0, 1000), ADCtotal, D, and Dapp of malignant tumors were significantly lower than those of benign lesions (all p < 0.001). D*, f, and Kapp showed no statistically significant differences between the two groups. ADCtotal showed the highest area under the curve (AUC = 0.862), followed by ADC(0, 800)(AUC = 0.844), ADC(0, 600)(AUC = 0.843), D(AUC = 0.834), ADC(0, 1000)(AUC = 0.834) and ADC(0, 500)(AUC = 0.824), Dapp(AUC = 0.796), and ADC(0, 300) (AUC = 0.773). However, the difference in diagnostic efficacy among these parameters was not statistically significant (p > 0.05). CONCLUSION: Intravoxel incoherent motion (IVIM) and DKI-derived parameters have similar performance compared with conventional ADC in differentiating SPLs. KEY POINTS: • Mono- and biexponential DWI and DKI are feasible for differentiating SPLs. • ADC (0, ≥500) has better performance than ADC (0, <500) in assessing SPLs. • IVIM and DKI have similar performance compared with conventional DWI in differentiating SPLs.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Diferencial , Imagem Ecoplanar/métodos , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Zhongguo Gu Shang ; 30(10): 933-939, 2017 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-29457416

RESUMO

OBJECTIVE: To system evaluate the clinical effect and safety of PFNA and InterTAN internal fixation methods for femoral intertrochanteric fracture. METHODS: According to the Cochrane systemic analysis method, randomized controlled trials and quasi-randomized controlled trials which were about the comparison of PFNA and InterTAN for intertrochanteric fracture were collected from Cochrane Library(2017, issue 4), PubMed (January, 2003-May, 2017), Wanfang Med Online (January, 2003-May, 2017) and China Academic Journals Full-text Database(January, 2003-May, 2017) by computer searching. Cross-checking was done after assessing the quality of the included trials and extracting the data by two reviewers independently. Data analysis were performed with RevMan 5.3. RESULTS: Two randomized controlled trials and five quasi-randomized controlled trials involving 611 cases met the inclusion criteria. The meta-analyses showed no significant differences between the two methods on Harris scores[MD=-1.00, 95%CI(-2.29, 0.28), P=0.13], union time[MD=0.04, 95%CI (-0.70, 0.77), P=0.92], full weight-bearing time[MD=1.06, 95%CI(-0.29, 2.42), P=0.13], hospital stay[MD=-0.04, 95%CI (-0.52, 0.45), P=0.89] and length of incision[MD=-1.00, 95%CI (-2.64, 0.65), P=0.23]. There were significant differences between the two methods on operative time[MD=-25.75, 95%CI (-37.47, -14.03), P<0.000 1], intraoperative blood loss[MD=-55.67, 95%CI(-108.07, -3.27), P=0.04] and the internal fixation complication rate[MD=4.17, 95%CI (1.33, 13.08), P=0.01]. CONCLUSIONS: Both PFNA and InterTAN could provide good effect for intertrochanteric fracture. The operation time of PFNA is shorter than that of InterTAN, and there is less blood loss during operation. PFNA may be the first choice for the treatment of patients who have many complications and can't endure long-time operation. The complications of PFNA are more than those of InterTAN. In patients with long life expectancy and high requirements, InterTAN may be preferentially selected to reduce complications. According to the patient's situation, after a comprehensive consideration, appropriate treatment can be selected.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas do Quadril/cirurgia , Pinos Ortopédicos , China , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA