36 research outputs found
The preparation of 3,5-dihydroxy-4-isopropylstilbene nanoemulsion and in vitro release
We have reported a novel procedure to prepare 3,5-dihydroxy-4-isopropylstilbene (DHPS) nanoemulsion, using a low-energy emulsification method. Based on the phase diagram, the optimum prescription of nanoemulsion preparation was screened. With polyoxyethylenated castor oil (EL-40) as the surfactant, ethanol as the co-surfactant, and isopropyl myristate (IPM) as the oil phase, the DHPS nanoemulsion was obtained with a transparent appearance, little viscosity, and spherically uniform distribution verified by transmission electron microscopy and laser scattering analyzer. The nanoemulsion was also determined by FT-Raman spectroscopy. The DHPS nanoemulsion demonstrated good stability and stable physical and chemical properties. The nanoemulsion dramatically improved the transdermal release of DHPS (from 8.02 μg · cm−2 to 273.15 μg · cm−2) and could become a favorable new dosage form for DHPS
A Multilayer-Stacked UWB Yagi Antenna
By taking advantage of a wideband bow-tie antenna in the Yagi configuration, a novel multilayer-stacked ultra-wideband (UWB) Yagi antenna is proposed. First, the fundamental 3-layered UWB Yagi model is studied with respect to a few critical dimensions. Then, several directors are added to form a multilayer-stacked Yagi antenna, where the width of the directors is optimized in a monotonic decreasing manner. A sixlayered UWB Yagi antenna is studied by simulations. It covers 3.4-10.6 GHz with its return loss better than 10 dB, and it achieves a high directivity up to 13 dBi and a relative cross-polar level better than -10 dB in the whole band
Spatial and temporal variability in net primary production (NPP) of alpine grassland on Tibetan Plateau from 1982 to 2009
Abstract HKT-ISTP 2013
B
An Improved RSSI Measurement In Wireless Sensor Networks
AbstractNode localization is one of the basic problem in wireless sensor networks.The localization method based on RSSI measurement is studied in this paper. Because the RF signals is affected by the environment,the exact distance between the nodes can not obtain by RSSI measurement.The parameters of measurement model are determined by anchor nodes,and further correct the measurement data,which can reduce the measurement error.The above methods can effectively reduce the measurement error.The improved RSSI measurment can improve the accuracy of the unknown nodes localization
comparisonofphotocatalyticactivityoftio2filmdopednonuniformlybymnandzn
The thin films of TiO2, doped by Mn or Zn with nonuniform distribution, were prepared by sol-gel method under process control. The actinic absorption of the catalyst thin films was evaluated by UV-vis spectrophotometry. And the activity of the photocatalyst was evaluated by photocatalytic degradation kinetics of aqueous methyl orange under UV radiation. The results show that the photocatalytic activity of the TiO2 thin film can be evidently enhanced by Mn non-uniformly doping in the bottom layer and can be decreased by Mn doping in the surface layer. The activity of TiO2 thin film can be evidently enhanced by Zn non-uniform doping in either the bottom or the surface layer. But the activity of TiO2 is less affected by uniformly Zn doping. The different mechanisms for enhanced photocatalytic activity of Mn or Zn non-uniformly doped titanium dioxide film were discussed in terms of the separation of photon-generated carrier in the TiO2 films
UN Rescuing Child Soldiers Programme (UN-RCSP) Return the Childhood to Children
Child-soldiers, UN-RCSP, Global governance, Z13,
Evaluating the value of 18F-PSMA-1007 PET/CT in the detection and identification of prostate cancer using histopathology as the standard
Abstract Background Prostate-specific membrane antigen (PSMA) PET/CT is a highly regarded radionuclide imaging modality for prostate cancer (PCa). This study aimed to evaluate the diagnostic performance of 18F-PSMA-1007 PET/CT in detecting intraprostatic lesions of PCa using radical prostatectomy (RP) specimens as a reference standard and to establish an optimal maximum standardized uptake value (SUVmax) cutoff for distinguishing between PCa and non-PCa lesions. Methods We retrospectively collected 117 patients who underwent 18F-PSMA-1007 PET/CT before RP. The uptake of the index tumor and contralateral non-PCa lesion was assessed. Histopathology of RP specimens was used as the gold standard. Kappa test was used to evaluate the consistency of preoperative PSMA PET/CT staging and postoperative pathological staging. Finally, an SUVmax cutoff value was identified by receiver operating characteristic (ROC) curve analysis to distinguish PCa lesions from non-PCa lesions. A prospective cohort including 76 patients was used to validate the results. Results The detection rate of 18F-PSMA-1007 PET/CT for prostate cancer was 96.6% (113/117). 18F-PSMA-1007 had a sensitivity of 91.2% and a positive predictive value (PPV) of 89.8% for the identification of intraprostatic lesions. The consistency test (Kappa = 0.305) indicated poor agreement between the pathologic T-stage and PSMA PET/CT T-stage. Based on ROC curve analysis, the appropriate SUVmax to diagnose PCa lesions was 8.3 (sensitivity of 71.3% and specificity 96.8%) with an area under the curve (AUC) of 0.93 (P < 0.001). This SUVmax cutoff discriminated PCa lesions from non-PCa lesions with a sensitivity of 74.4%, a specificity of 95.8% in the prospective validation group. Conclusions 18F-PSMA-1007 PET/CT demonstrated excellent performance in detecting PCa. An optimal SUVmax threshold (8.3) could be utilized to identify lesions of PCa by 18F-PSMA-1007 PET/CT. Trial registration ClinicalTrials.gov Identifier: NCT04521894, Registered: August 17, 2020
Mesorectal reconstruction with pedicled greater omental transplantation to relieve low anterior resection syndrome following total intersphincteric resection in patients with ultra-low rectal cancer
Abstract Background Total intersphincteric resection (ISR) is the ultimate anus-preserving surgery for patients with ultra-low rectal cancer (ULRC), which can result in various degrees of anorectal dysfunction. Known as low anterior resection syndrome (LARS), it seriously affects the postoperative quality of life of patients. The aim of this study was to discuss the value of mesorectal reconstruction with pedicled greater omental transplantation (PGOT) to relieve LARS following total ISR in patients with ULRC, hoping to provide new ideas and strategies for the prevention and improvement of LARS. Methods We retrospectively analyzed hospitalization data and postoperative anorectal function of 26 ULRC patients, who were met inclusion and exclusion criteria in our center from January 2015 to February 2022. And combined with the results of anorectal manometry and rectal magnetic resonance imaging (MRI) defecography of some patients, we assessed comprehensively anorectal physiological and morphological changes of the patients after surgery, and their correlation with LARS. Results In this study, 26 patients with ULRC were enrolled and divided into observation group (n = 15) and control group (n = 11) according to whether PGOT was performed. There were no significant differences in surgical results such as operative time, intraoperative blood loss and postoperative complications between the two groups (P > 0.05). Postoperative follow-up showed that patients in both groups showed severe LARS within 3 months after surgery, but from the 3rd month after surgery, LARS in both groups gradually began to decrease, especially in the observation group, which showed faster recovery and better recovery, with statistically significant difference (P < 0.001). Through anorectal manometry, the mean rectal resting pressure in the observation group was significantly lower than that in the control group (P = 0.010). In addition, the postoperative thickness of the posterior rectal mesenterium in the observation group was significantly higher than that in the control group (P = 0.001), and also higher than the preoperative level (P = 0.018). Moreover, rectal MRI defecography showed that the neo-rectum had good compliance under the matting of greater omentum, and its intestinal peristalsis was coordinated. Conclusions ULRC patients, with the help of greater omentum, coordinated their neo-rectum peristalsis after total ISR and recovery of LARS was faster and better. PGOT is expected to be an effective strategy for LARS prevention and treatment of ULRC patients after surgery and is worthy of clinical promotion