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The performance of gradient and shim coils affect the quality of magnetic resonance imaging (MRI) directly. Conventional gradient/shim coils have some inherent disadvantages, such as the state of produced magnetic field is single and inflexible, many types of coils are required and the structure is complex, while the matrix gradient coils are able to overcome those problems. This paper introduces the concept and characteristics of matrix gradient coil, and reviews the current progresses in this research topic according to the structure and function of the gradient coil. The development tendency of matrix gradient coil in the future is proposed. In addition, the preliminary research on matrix gradient coil is presented.

Space optical remote sensor of high spatial resolution need achieve both light and small design and high imaging quality. An optimization method of optical remote sensor based on imaging chain simulation is presented. All factors in imaging chain are analyzed according to MTF models and noise models. Additionally, image restoration is considered as one part of imaging chain. The simulation model are built to optimize remote sensor overall performance by the evaluation of remote sensor and simulation image. This method is used to enhance image quality and reduce the development difficulties of optical remote sensor. The test validates the feasibility and predominance of the optimization design method.

Electrodeposition of lithium is of both fundamental significance and practical importance. However, Li deposition has to proceed beneath a solid‐electrolyte interphase (SEI). Herein, we present a fundamental study on the formation of SEIs and their influences on Li initial‐stage deposition on Cu in Py14 cation‐based ionic liquids (ILs) combined with different ratios of TFSI and FSI anions. Different SEIs are pre‐formed on Cu by using cyclic voltammetry, followed by detailed characterizations by XPS and AFM, which elucidate that all the SEIs bear mosaic‐like I−O structures but with different compositions and structures and varying thicknesses of approximately 60–150 nm. The Li initial‐stage depositions are studied by using cyclic voltammetric and potential stepping techniques, and current‐time transients are analyzed with the aid of the Scharifker‐Hills model. Discrepancies in nucleation density and diffusion coefficients and their relationships with overpotentials are investigated in correlation with the SEI structures. The present work demonstrates that interfacial and bulk properties of SEI strongly affect the Li deposition processes, which provides opportunities for uniform Li deposition. [ABSTRACT FROM AUTHOR]

Chinese HY-1C/1D satellites will use a 5nm/10nm-resolutional visible-near infrared(VNIR) hyperspectral sensor with the solar calibrator to cross-calibrate with other sensors. The hyperspectral radiance data are composed of average radiance in the sensor's passbands and bear a spectral smoothing effect, a transform from the hyperspectral radiance data to the 1-nm-resolution apparent spectral radiance by spectral reconstruction need to be implemented. In order to solve the problem of noise cumulation and deterioration after several times of iteration by the iterative algorithm, a novel regression method based on SVM is proposed, which can approach arbitrary complex non-linear relationship closely and provide with better generalization capability by learning. In the opinion of system, the relationship between the apparent radiance and equivalent radiance is nonlinear mapping introduced by spectral response function(SRF),SVM transform the low-dimensional non-linear question into high-dimensional linear question though kernel function, obtaining global optimal solution by virtue of quadratic form. The experiment is performed using 6S-simulated spectrums considering the SRF and SNR of the hyperspectral sensor, measured reflectance spectrums of water body and different atmosphere conditions. The contrastive result shows: firstly, the proposed method is with more reconstructed accuracy especially to the high-frequency signal; secondly, while the spectral resolution of the hyperspectral sensor reduces, the proposed method performs better than the iterative method; finally, the root mean square relative error(RMSRE) which is used to evaluate the difference of the reconstructed spectrum and the real spectrum over the whole spectral range is calculated, it decreses by one time at least by proposed method. [ABSTRACT FROM AUTHOR]

Highlights: [•] It is first used excess spectra to investigate the interactions between [BMIM][BF4] and DMSO. [•] C2–H is the main interaction site in investigated complexes. [•] The two turning points of the wavenumber shift changes of C2–H may indicate the dilution process. [•] Hydrogen-bond interactions are the main cause influencing the wavenumber shift changes. [ABSTRACT FROM AUTHOR]

Objective: To reveal the relationship between iodine nutrition and the change of spectrum on thyroid diseases through comparing the different iodine environments pre- and post- the universal salt iodization(USI)campaign., Methods: To compare the urinary iodine concentration between 1000 normal people and 5998 patients with thyroid disease who had undergone surgical operations, from 4 major cities, including iodine deficient and rich areas of Guangxi Zhuang Autonomous Region., Results: After USI was put into practice, the urinary iodine concentration of patients with thyroid appeared higher than those of normal people(324.3 µg/L vs. 238.5 µg/L, P < 0.05). The urinary iodine concentrations of nodular goiter,Graves disease, toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis were higher than those before the USI was taken(263.8 µg/L vs. 69.75 µg/L, 289.7 µg/L vs. 228.3 µg/L, 346.8 µg/L vs. 268.4 µg/L, 350.3 µg/L vs. 316.2 µg/L and 378.5 µg/L vs. 305.8 µg/L). The proportions of toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis appeared as 7.59% vs. 4.80%, 5.85% vs. 4.02% and 3.88% vs. 2.46%, all higher than those before the implementation of USI, except the nodular goiter which showed a reduction (63.56% vs. 69.75%)., Conclusion: The spectrum of thyroid diseases appeared an obvious change in Guangxi within the last 10-year implementation of USI. However, the excessive intake of iodine might serve as a risk factor for toxic nodular goiter, thyroid papillary carcinoma and Hashimoto's thyroiditis.

Aim: To explore the influence of angiotensin-(1-7) [Ang-(1-7)] on cell activation and extracellular matrix secretion in rat renal interstitial fibroblasts (NRK-49F) induced by aldosterone (ALD)., Methods: The NRK-49F cells were cultured in vitro, and then were divided into control group, ALD group, Ang-(1-7) group, and ALD+Ang-(1-7) group. When the cells were cultured for 48 h, the expression of α-smooth muscle actin (α-SMA) (a sign of cell activation) was detected by immunocytochemistry; the level of collagen type I (Col I ) in the cultured supernatant was measured by enzyme-linked immunosorbent assay (ELISA). When the cells were cultured for 30 min, the expressions of phosphorylated and total ERK1/2 (pERK1/2, tERK1/2) in the cell lysate were detected by Western blotting., Results: Compared with control group, the expressions of α-SMA, Col I and the Phos/Total ERK1/2 ratio in ALD group and ALD+Ang-(1-7) group increased significantly (P<0.05). Compared with ALD group, the expressions of α-SMA, Col I and the Phos/Total ERK1/2 ratio in ALD+Ang-(1-7) group decreased significantly (P<0.05)., Conclusion: Ang-(1-7) can inhibit ALD-induced cell activation and decrease the secretion of Col I in rat renal interstitial fibroblasts. Inhibition of ERK1/2 pathway may play an important role in this process.

Aim: To explore the influence of angiotensin-(1-7)[Ang-(1-7)] on angiotension II(Ang II) induced rat's tubular epithelial-myofibroblast transdifferentiation and the secretion of extracellular matrix., Methods: The NRK52E were maintained and sub-cultured treated with Ang-(1-7) (10(-6); mmol/L) and Ang II(10(-6); mmol/L) for 24, 48, 72, 96 hours, we detect the protein expressions of E-cadherin and α-SMA by immunocytochemistry method; The content of Col I and FN in the cultured supernatant were measured by ELISA; The mRNA expression of E-cadherin, α-SMA, Col I and FN was detected by real-time PCR., Results: Treat with ang II 96 h, the protein and mRNA expression of E-cadherin decreased significantly (P<0.05), but the protein and mRNA expression α-SMA, col I and FN increased significantly (P<0.05); treat with Ang II and Ang-(1-7), the protein and mRNA expression of E-cadherin increased significantly (P<0.05), but the protein and mRNA expression α-SMA, col I and FN decreased significantly (P<0.05)., Conclusion: Ang-(1-7) can inhibits Ang II-induced rat's tubular epithelial myofibroblast transdifferentiation and decrease the secretion of FN and Col I.

Objective: This study aimed to investigate Chinese medical interns' cancer knowledge and associated factors, focusing on cancer screening., Methods: A questionnaire survey was conducted in ten leading Chinese medical schools from June to July in 2011. Medical interns were invited to fill the questionnaire., Results: Out of the 1350 copies sent, 1135 eligible responses were returned. Around 50% of interns had positive attitude toward oncology, but the knowledge score was low, particularly in screening. The percentages of scores were 44.8% (8.95/20) for overall and only 29.6% (2.07/7) for screening. The majority of internship length in oncology department was eight to fourteen days. Screening and prevention was ranked as third most taught, following diagnosis and treatment. Multivariate analysis showed that positive attitude to oncology correlated with positive self-evaluated overall (OR = 1.76, 95% CI (1.45, 2.12)) and screening (OR = 1.62, 95% CI (1.35, 1.95)) competence, but unexpectedly predicted lower screening score (OR = 0.77, 95% CI (0.61, 0.97)). Interns with positive self-evaluated screening competence were not found to possess higher cancer screening knowledge., Conclusion: Current medical education in Chinese medical schools fails to equip interns with optimal cancer knowledge, particularly in screening, even in interns who hold positive view to oncology. Interns' self-evaluated competence is not proportional to their knowledge scores.

Objective: To observe the effects of low-level laser irradiation on mesenteric microcirculation of rats in vivo in the early stage of endotoxemia (ETM)., Methods: The experimental model of ETM was reproduced by injection of lipopolysaccharide (LPS). Sixty healthy male Sprague-Dawley (SD) rats were divided into three groups used random number table: control group, LPS group and low-level laser irradiation group, each group included 20 rats which were subdivided into four temporal subgroups (1, 2, 4, 6 hours, respectively). In low-level laser irradiation group, the rats were irradiated by type SLT semiconductor laser (650 nm, 5 mW) on unilateral femoral artery and vein, and blood vessel of the ear concurrently for 30 minutes. The interference course was vertical irradiation taken at 30 minutes after the injection of LPS. At 1, 2, 4, 6 hours after the injection of LPS, changes in mesenteric microcirculation and microcirculatory blood flow were recorded with the laser Doppler flowmeter, the velocity of red blood cells in venules was observed, and the number of open capillaries and adherent leukocytes were recorded., Results: The blood flow velocity (mm/s) of the mesenteric microcirculation in LPS group was accelerated at 1 hour and 2 hours after LPS injection (1 hour: 0.190+/-0.007 vs. 0.174+/-0.009, 2 hours: 0.200+/-0.010 vs. 0.172+/-0.015, both P<0.05, respectively), but decelerated at 6 hours (0.116+/-0.015 vs. 0.164+/-0.011, P<0.05). The blood flow volume in the mesenteric vessels and the number of open capillaries did not show any significant change at that time. Significant increase in number of adherent leukocytes was observed at 2, 4, 6 hours after injury (2 hours: 2.60+/-1.14 vs. 0.40+/-0.55, 4 hours: 5.40+/-0.89 vs. 0.40+/-0.55, 6 hours : 5.40+/-1.52 vs. 0.60+/-0.90, all P<0.05, respectively). The state of blood flow in the microcirculation became abnormal. After irradiated with laser in low dose, the blood flow velocity was smooth and stable (mm/s, 1 hour: 0.174+/-0.011, 2 hours: 0.180+/-0.023, 4 hours: 0.168+/-0.013, 6 hours: 0.162+/-0.023), and the number of adherent leukocytes was reduced significantly at 4 hours and 6 hours than that in LPS group (4 hours: 2.00+/-0.71 vs. 5.40+/-0.89, 6 hours: 2.60+/-1.52 vs. 5.40+/-1.52, both P<0.05) and the microcirculatory flow state was improved obviously., Conclusion: Low-level laser irradiation may ameliorate the local mesenteric microcirculation, alleviate the microcirculatory disorder in early stage of ETM.