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Interferometric Synthetic Aperture Radar (InSAR) coherence is important not only in determining measurement quality but also for extracting thematic information about objects on the ground in combination with backscattering coefficient. The decorrelation of repeat-pass InSAR caused by soil moisture change has received little attention in comparison with other sources of decorrelation. In this paper, we use ENVISAT ASAR data and laboratory experiments to analyze the repeat-pass InSAR coherence loss results due to soil moisture change. C-band ASAR data has high coherence over bare soil and grassland areas, which indicates that these two types of land cover are good choices for the analysis of InSAR coherence loss due to soil moisture change. In addition, spaceborne SAR with short revisit capability, has great potential for this specific application, even for agricultural fields. We conducted further analysis of the soil-sample laboratory data acquired in an anechoic chamber because of its controllable environment and the ability to exclude other sources of decorrelation. We found that the lower frequency range, 2-2.5 GHz, has the highest coherence and is the most insensitive to the initial soil moisture value. This indicates that the S band is more advantageous than the C band when using InSAR coherence to detect soil moisture change. This is true at least with respect to the S band's high coherence level and insensitivity to initial soil moisture values.

Aiming at detecting the change regions of high resolution Synthetic Aperture Radar (SAR) images, we propose to use the Dempster-Shafer (D-S) evidence theory to fuse coherent/incoherent features from sensors that form an integral part of the system. First, we use the Simple Linear Iterative Clustering (SLIC) segmentation algorithm to implement multi-scale joint segmentation for multi-temporal SAR images. Second, we extract multiple intensity and coherence difference features on each segment level by SLIC using mean operator to complete the fusion of multi-scale features to get the multi-feature difference mapped by a ratio operator. Finally, we fuse the multi-feature difference maps to get the final change detection result using the D-S evidence theory. The experimental results in our study prove the effectiveness of our proposed computational algorithm.

This study proposes a novel Multiple Input Multiple Output (MIMO) microwave imaging mode based on arc antenna array, which is mounted on the belly of platform. In this mode, an arc aperture is quickly synthesized using an MIMO. Consequently, high space and time resolution images of the illuminated scene around the platform are acquired. First, an imaging principle model based on arc antenna array is described, and its signal model is developed. Then, an imaging algorithm based on confocal projection is discussed and the performance of the mode is analyzed. Finally, the feasibility of the imaging mode and the validity of the proposed algorithm are demonstrated with a numerical simulation.

The Pixel Relativity (PR) measurement of SAR image, which is the key of the despeckling techniques based on weighted average, is researched in three aspects. Firstly, the rationality of ratio PR model is expounded, and two new ratio PR models, which are the LOG-domain Gaussian model and the pixel similarity probability model, are proposed. Meanwhile, the Probability Density Function (PDF) of SAR image and the PDF of the ratio between pixels are transformed into ratio PR models. Then, in order to evaluate the four ratio PR models, the weighted maximum likelihood filters are designed using the PR. Finally, a novel method, performed by calibrating the maximum location of the PR model, is introduced to improve the radiation preservation of those models whose maximum do not locate at 1. The effectiveness of the two proposed PR models and the approach to calibrate the maximum location of the PR model, are indicated by the theoretical analysis and experimental comparison.

Based on the ratio distance pixel-relativity and thresholding pixel-similarity, a modified non-local filter is proposed for SAR image despeckling in this paper. Firstly, the ratio distance pixel-relativity is obtained by transforming the joint probability density function of two pixels. Then, a table of pixel-similarity threshold, as a function of the SAR image look number and neighboring reflectivity ratio, is trained according to the minimum error probability. Finally, the pixel-similarity threshold is applied to select similar pixels from the searching window for the real reflectivity estimation. The proposed approach was verified by synthetic and real SAR images, and was compared with the PPB and LHRS-PRM filters. The visual quality and the quantification comparison show that the proposed approach is excellent not only in the reconstruction of the uniform area, the character of edges, texture, and details, but also with the lower computation complexity.

Aim: To explore the actual experience of training effect of Baduanjin on patients with hemiplegic limb dysfunctions after cerebral infarction through semistructured interviews and promote Baduanjin training application in clinical and community settings. Design: This qualitative study was conducted using the conventional content analysis approach. Methods: Twenty‐five patients with hemiplegic limb dysfunctions after cerebral infarction were recruited as participants by applying purposive sampling method between September 2017–December 2020 in the physical therapy department of a rehabilitation hospital affiliated with Fujian University of Traditional Chinese Medicine in China. Semistructured interviews were conducted after patients participated in Baduanjin training for 6 weeks. Data were analysed using qualitative content analysis method of Graneheim and Lundman. Results: Three major themes were identified after analysis, namely improving functions of hemiplegic limbs, improving the condition of the entire body and the feelings of practice. The participants indicated that Baduanjin could improve the limb functions and general conditions of hemiplegic patients. Their experience in practicing Baduanjin was generally positive, and they were willing to continue practicing. [ABSTRACT FROM AUTHOR]

In this letter, a modified bilateral filter suitable for synthetic aperture radar (SAR) image despeckling, named space-domain filter with alterable window (SFAW), is proposed. SFAW features geometric adaptivity, in both spatial and similarity functions, respectively driven by the following: 1) the local coefficient of variation ( CV) and 2) the joint probability density function model of two pixels having the same reflectivity. Tests on synthetic and real SAR images show that SFAW notably smoothes speckle with unperceivable detail blurring and achieves better performances than other related methods. [ABSTRACT FROM PUBLISHER]

This study aimed to develop and assess a chitosan biomedical antibacterial gel ZincOxide-GrapheneOxide/Chitosan/β-Glycerophosphate (ZnO-GO/CS/β-GP) loaded with nano-zinc oxide (ZnO) and graphene oxide (GO), known for its potent antibacterial properties, biocompatibility, and sustained drug release. ZnO nanoparticles (ZnO-NPs) were modified and integrated with GO sheets to create 1% and 3% ZnO-GO/CS/β-GP thermo-sensitive hydrogels based on ZnO-GO to Chitosan (CS) mass ratio. Gelation time, pH, structural changes, and microscopic morphology were evaluated. The hydrogel's antibacterial efficacy against Porphyromonas gingivalis, biofilm biomass, and metabolic activity was examined alongside its impact (MC3T3-e1). The findings of this study revealed that both hydrogel formulations exhibited temperature sensitivity, maintaining a neutral pH. The ZnO-GO/CS/β-GP formulation effectively inhibited P. gingivalis bacterial activity and biofilm formation, with a 3% ZnO-GO/CS/β-GP antibacterial rate approaching 100%. MC3T3-e1 cells displayed good biocompatibility when cultured in the hydrogel extract.The ZnO-GO/CS/β-GP thermo-sensitive hydrogel demonstrates favorable physical and chemical properties, effectively preventing P. gingivalis biofilm formation. It exhibits promising biocompatibility, suggesting its potential as an adjuvant therapy for managing and preventing peri-implantitis, subject to further clinical investigations.

Objective: To observe the effect of chiropractics on intervertebral disk extracell matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, cellular collagen type Ⅱ (COL-Ⅱ), tissue inhibitor 1 of metalloproteinase (TIMP-1) and extracellular matrix (ECM) in the rats with cervical spondylosis, so as to explore its mechanism underlying improvement of cervical spondylosis., Methods: A total of 40 SD rats were randomized into a sham group, a model group, a chiropractics group and a mobic group, 8 rats in each one. The model was established by static-dynamic imbalance method. The rats in the chiropractics group were treated with chiropractic therapy for two courses, 14 times a day and 14 days as a course. The rats in the mobic group were treated with intragastric administration of mobic. The expression of MMP-1, MMP-3, MMP-13, COL-Ⅱ and TIMP-1 in the intervertebral disk tissue were detected by immunohistochemistry, and the protein expression of ECM was detected by Western blot., Results: Compared with those in the sham group, the expressions of MMP-1, MMP-3, MMP-13 in the model group increased (all P <0.05), and COL-Ⅱ, TIMP-1 decreased (both P <0.05).Compared with those in the model group, the expressions of MMP-1, MMP-3, MMP-13 in the chiropractics group and the mobic group decreased (all P <0.05), and COL-Ⅱ, TIMP-1 increased (all P <0.05). Compared with that in the sham group, the expression of ECM protein in the model group decreased ( P <0.05). Compared with that in the model group, the expression of ECM protein in the chiropractics group and the mobic group increased (both P <0.05)., Conclusions: Chiropractics may improve the degeneration in rats with cervical spondylosis by regulating intervertebral disc ECM system and relevant metabolic enzymes.

Objective: To compare the efficacy and safety of 3 different regimens, namely MAC, FLAG and CAG, as the re-induction chemotherapy for acute myeloid leukemia(AML) patients with primary induction failure and relapse., Methods: The clinical data of 156 AML patients with primary induction failure and relapse, except patients with acute promyelocytic leukemia(APL), treated with any of the above 3 regimens in our center from January 2008 to April 2016 were analyzed retrospectively. According to the treatment regimens, 156 patients were divided into MAC group (n=60), FLAG group (n=45) and CAG group (n=51). The complete remission(CR), partial remissison(PR), overall survival(OS), disease-free survival(DFS) and adverse events during the treatment were analyzed, so as to compare and evaluate the efficacy and safety of the 3 different regimens., Results: After 1 course of re-induction chemotherapy, CR in MAC group was significantly higher than that in FLAG and CAG group (55.4% vs 34.1% vs 34.0%)(P<0.05). The OS was not statistically significantly different among 3 groups (P>0.05) with a median OS of 11 months, 5.46 months and 10.2 months, respectively. The myelosuppression was the main adverse event with no significant difference among the groups(P>0.05). More patients treated with MAC regimen underwent febrile neutropenia (93.3% vs 86.7% vs 64.7%)(P<0.001). However, the incidence of fatal infections was not signicantly different among 3 groups(5% vs 8.9% vs 5.9%)(P>0.05)., Conclusion: Compared with FLAG and CAG regimen, the MAC regimen can enable more AML patients with primary induction failure and refractory to achieve CR without increasing severe adverse events,therefore,this regimen may provide a opportunity for patients to recieve hematopoietic stem cell transplantation.

Objective: To evaluate the long-term clinical effect of autologous peripheral blood mononuclear cells (PB-MNC) on critical limb ischemia (CLI) in patients with thromboangiitis obliterans (TAO) patients., Methods: The clinical data of 22 patients with CLI caused by TAO from July 2004 to May 2013 were analyzed retrospectively, 22 patients were divided into 2 groups; out of them 12 cases in one group were treated with granulocyte colony-stimulating factor (G-CSF)-mobilized autologous peripheral blood mononuclear cells (auto-PBMNC group), 10 cases in another group received conservative treatment (CT group). The log-rank test was used to compare the long-term outcomes in auto-PBMNC group and CT group., Results: The wound healing rate (P=0.016) and CLI-free rate (P=0.013) were significantly higher in PB-MNC group compared with that in CT group. No difference was found in amputation rates between the 2 groups (major amputation: P=0.361, minor and major amputation: P=0.867). No patients died or no serious adverse events occurred during the follow-up period., Conclusion: The auto-PBMNC therapy can significantly promote the wound healing, and protect against CLI in TAO patients, but the risk of amputation is not low in comparison with conservative treatment.

In nature, plants have to cope with a wide range of stress conditions that often occur simultaneously or in sequence. To investigate how plants cope with multi-stress conditions, we analyzed the dynamics of whole-transcriptome profiles of Arabidopsis thaliana exposed to six sequential double stresses inflicted by combinations of: (i) infection by the necrotrophic fungus Botrytis cinerea, (ii) herbivory by chewing larvae of Pieris rapae, and (iii) drought stress. Each of these stresses induced specific expression profiles over time, in which one-third of all differentially expressed genes was shared by at least two single stresses. Of these, 394 genes were differentially expressed during all three stress conditions, albeit often in opposite directions. When two stresses were applied in sequence, plants displayed transcriptome profiles that were very similar to the second stress, irrespective of the nature of the first stress. Nevertheless, significant first-stress signatures could be identified in the sequential stress profiles. Bioinformatic analysis of the dynamics of co-expressed gene clusters highlighted specific clusters and biological processes of which the timing of activation or repression was altered by a prior stress. The first-stress signatures in second stress transcriptional profiles were remarkably often related to responses to phytohormones, strengthening the notion that hormones are global modulators of interactions between different types of stress. Because prior stresses can affect the level of tolerance against a subsequent stress (e.g. prior herbivory strongly affected resistance to B. cinerea), the first-stress signatures can provide important leads for the identification of molecular players that are decisive in the interactions between stress response pathways., (© 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.)

Objective: To extract the volatile oils from Lithospermum erythrorhizon via ultrasound-enhanced sub-critical water extraction (USWE) and compare with ultrasound-enhanced solvent extraction (USE) and steam distillation extraction (SD)., Methods: The extraction yield of the volatile oils, the containing components of extract, the effect of scanvenging activities on free radical DPPH and reducing activities as well as the inhibitory on escherichia coli and staphylococcus aureus were investigated., Results: The extraction yield of volatile oils by USWE, USE and SD were 2.39%, 1.93% and 0.62%, respectively, the extracts by three methods all contained six major components, but the extracts by SD and USE contained more impurities. The inhibitory effect on escherichia coli and staphylococcus aureus of the extract by SD and its reducing action were the best,but those by USWE were the worst., Conclusion: the extraction yield of volatile oils by USWE is the highest, and it contains less impurities based on the worst in reducing power and inhibitory effects.

Objective: To analyze the efficacy and its correlation with species of transplant cells of autologous mobilized peripheral blood (PB) mononucleated cells (MNCs) transplantation on 59 patients with lower limbs ischemia., Methods: Fifty-nine patients were evaluated with symptoms scores and after that their PBMNCs were mobilized and collected and then injected into the ischemic area at equal distance. They effectiveness and scores were evaluated at 7th day and 4th month after therapy. The correlation of CD34(+) cells and of MNCs with effectiveness was analysed respectively, and formula for correlations between them and effectiveness was calculated., Results: After MNCs injection, the effectiveness was observed both at 7th day and 4th month. The correlation of MNCs with effectiveness was stronger than that of CD34(+) cells (the effectiveness was represented by nimodipine value), According to the formula of nimodipine value, the value of the latter = 0.484 + 1.055 × CD34(+) cells number and the former = 0.288 + 0.401 × MNCs number with a correlation coefficient of R = 0.461 (P = 0.047) and R = 0.473 (P = 0.000) respectively., Conclusion: Autologous mobilized PBMNCs number is a better indicator for effectiveness than CD34(+) cells number.