For orthogonal frequency-division multiplexing (OFDM) communication systems, the frequency offset in mobile radio channels distorts the orthogonality between sub-carriers, which results in Intercarrier Interference(ICI) and seriously degrades the performance of systems. Based on ICI coefficients analysis, a novel precoder design scheme is proposed for mitigation of ICI. In this technique, precoder matrix is designed by the way of linear counteraction and inserted in the former transmitter signal. Computer simulation results show that this new scheme can effectively reduce ICI and significantly provide the carrier-interference power ratio improvement. Compared with existing ICI mitigation schemes with channel estimation, the proposed scheme has lower computational complexity, and compared with self-cancellation scheme, the bandwidth efficiency can be improved in this proposed scheme. The proposed scheme also has better convergence stability for time-varying frequency selective fading channel.

In order to investigate the impact of channel estimation error on channel capacity of multiple input multiple output (MIMO) system, a novel method is proposed to explore the channel capacity in correlated Rayleigh fading environment. A system model is constructed based on the channel estimation error at receiver side. Using the properties of Wishart distribution, the lower bound of the channel capacity is derived when the MIMO channel is of full rank. Then a method is proposed to select the optimum set of transmit antennas based on the lower bound of the mean channel capacity. The novel method can be easily implemented with low computational complexity. The simulation results show that the channel capacity of MIMO system is sensitive to channel estimation error, and is maximized when the signal-to-noise ratio increases to a certain point. Proper selection of transmit antennas can increase the channel capacity of MIMO system by about 1 bit/s in a flat fading environment with deficient rank of channel matrix.

In order to better accommodate heterogeneous quality of service (QoS) in wireless networks, an algorithm called QeS-aware power and admission controls (QAPAC) is proposed. The system is modeled as u non- cooperative game where the users adjust their transmit powers to maximize the utility, thus restraining the interferences. By using adaptive utility functions and tunable pricing parameters according to QoS levels, this algorithm can well meet different QoS reqniremcnts and improve system capacity compared with those that ignore the QoS differ- ences.

Objective To explore the continuous improvement to reduce the suctioning pediatrics lumen instruments return-cleaning rate of the first time washing, improve work efficiency and reduce the cost by applying root cause analysis. Methods Using causal analysis of fishbone diagram to analysis and verify the main reason of leading to high lumen instruments return-cleaning rate. According to the three terminal factors of continuous quality improvement, quality control group was set up, lumen instruments cleaning quality control standards was made, water flow mode of lumen instruments cleaning was changed, selected the appropriate cleaning tools and real picture show, synchronize quality control measures of publishing the quality and safety board. Compared before and after return-cleaning rate of three different detection methods and the different parts of the same suction lumen instruments. Results Before carrying out eye-measurement, cotton swab to wipe, ATP bioluminescence back washing rate was 0.89% (2/225), 7.11%(16/225), 27.11%(61/225), respectively after implementation of 0, 0.44%(1/226), 3.98%(9/226), visual observation before and after the return rate of washing was no statistically significant difference (χ2=2.018, P>0.05);Cotton swab to wipe, ATP bioluminescence back washing rate difference was statistically significant (χ2=13.820, 45.999, P<0.01). The lumen instruments total return-washing rate was decreased from 35.11% (79/225) to 4.42% (10/226). Among them, the return- washing rate of the inside surface of lumen instruments was decreased from 32.89% (74/225) to the 3.10% (7/226) and the difference was statistically significant(χ2=67.028, 67.915,P<0.01). By contraries, the thread interface and the outside surface of lumen instruments return- cleaning rate before and after the implementation has no statistical significance (P>0.05). Conclusions ATP bioluminescence assay has fine effects to detect the return-washing rate of the inner wall of the lumen instruments. The Root Cause Analysis method significantly reduced the return-washing rate of the inside surface of the suction lumen instruments, improve the efficiency, save the medical cost and reduce the hospital infection.

Objective To review the imaging appearances and clinical symptoms of primary hepatic and gallbladder neuroendocrine carcinomas (PHGNC). Methods Five patients (4 females and 1 male) were examined. Long-term diarrhea not controlled by drug was found in four patients, and two of them accompanied by abdominal pain. The liver rupture occurred in one case due to the huge tumor bleeding. Five patients were examined by using ultrasonography (US), four patients by CT, and three patients by hepatic angiography. The tumor originated from liver in three cases, from liver and gallbladder in one case, and from gallbladder in one case. The tumors were diagnosed by surgery in 3 cases, by biopsy and by autopsy in 1 case, respectively. Results Multiple hyperechoic inhomogeneous masses in two cases and hypoechoic inhomogeneous masses in one case were revealed, all with some small fluid areas and abundant vessels. A huge cyst-solid tumor was clearly demonstrated by using US. A small mural nodule along the gallbladder wall was displayed by using US in a gallbladder tumor, and it showed no specific sign in the diagnosis. CT findings included hypodense inhomogeneous masses on plain CT scan, and slightly enhanced masses with some small fluid areas after injection of contrast agent. A huge cyst-solid tumor was clearly displayed by CT due to the hemorrhage, necrosis, and cystic changes in the tumor. Hepatoangiography displayed abundant vessels and stain in the solid part of the tumor, and absent vessel in the cystic region of the cyst-solid tumor accompanied by dislocation of surrounding vessels. Conclusion Imaging appearances of the liver tumor were inhomogeneous mass with abundant vessels and tumor stains. Imaging appearances of the gallbladder tumor were raised mural nodule along the gallbladder wall without specific sign in the diagnosis of the tumor. The tumor may develop hemorrhage, necrosis, and cystic changes if it is large enough. PHGNC was prone to hepatic metastases. The patients often presented with diarrhea and abdominal pain.

Objective:To investigate the anti-proliferation effect of carvacrol on human gastric cancer cell BGC-823 and explore the molecular mechanism. Methods:The proliferation of BGC-823 cells was evaluated by MTT assay. Flow cytometry was used to ana-lyze the cell apoptosis after exposed to carvacrol. Transwell assay was used to analyze the effect of carvacrol on cell metastasis. Quanti-tative realtime-PCR was used to detect the expression of MMP-9 and TIMP-1. The expression of caspase-9 and PARP,and the activa-tion of ERK and P38 were detected by Western blot. Results:The incubation with carvacrol resulted in a significant inhibition of BGC-823 cell proliferation. After the treatment with carvacrol,the apoptotic rate was significantly increased( 0 μmol · L-1 vs 10 μmol · L-1 ,P<0. 000 1;0 μmol·L-1 vs 20 μmol·L-1 ,P<0. 000 1;0 μmol·L-1 vs 40 μmol·L-1 ,P<0. 000 1;0 μmol·L-1 vs 80μmol·L-1 ,P<0. 000 1)and the invasion ability was decreased(0 μmol·L-1 vs 80 μmol·L-1 ,P<0. 000 1). The expression of caspase-9(0 μmol·L-1 vs 80 μmol·L-1,P<0. 000 1)and TIMP-1 was increased(P<0. 000 1),PRAP fragment occurred(P<0. 000 1)and P38 signaling pathway was activated in the carvacrol treated group,while the expression of MMP-9 activity of ERK signa-ling pathway was inhibited(P<0.000 1). Conclusion:Carvacrol can inhibit cell growth and invasion,and induce cell apoptosis, which is closely related to MAPK signaling pathway.

Objective To evaluate the value of echocardiography in transcatheter closure of ruptured sinus of Valsalva aneurysm(TC-RSVA).Methods TC-RSVA was attempted in 11 patients.The location,shape,size of defects and its relationship with the neighbor structures were revealed before the procedure.Then the deployment of occluder was monitored during the procedure,and the effectiveness was observed in the follow-up.Results Eleven patients were diagnosed as the isolated RSVA by echocardiography.The size of defects was 2 - 13 mm estimated by echo.The procedures were successful in all patients.Usually the Amplatzer duct occluders were chosen to be 1 to 5 mm larger than the size of defects.Three patients had mild residual shunt during the procedure,which all dispeared in the first month of follow-up,but one of them demonstrated recurrent mild residual shunt in the 32nd month of follow-up.There was no aggravating aortic regurgitation in the follow-up.Conclusions TC-RSVA is relatively safe and effective.Observation of long-term effectiveness is still necessary.Echocardiagraphy plays an important role in TC-RSVA.

Objective To compare the safety and clinical efficiency between minimally invasive percutaneous nephrolithotomy(MPCNL)in supine position and flexible ureteroscopy(FURS)in management of proximal ureteral calculi.Methods From Oct.2010 to May.2012,76 patients with single proximal ureteral calculus between 10-20 mm failed in SWL or other conservative therapy accepted MPCNL (32 cases)or FURS(44 cases).There was no significant difference between the groups in base-line parameters.Stone sizes were(15.6±2.5)mm and(14.9±2.3)mm,P＞0.05.Procedural time,post-operative hospitalization stay,complication rates(Clavien degree Ⅱ or over)and stone free rates were compared.Results In these two groups,procedural time was(49.3± 11.7)and(67.2± 17.3)min,P＜0.05,postoperative hospitalization stay were(4.2±1.1)and(1.8±0.8)days,P＜0.05,complication rates were 12.5％ and 6.8％,P＞0.05 and stone free rates(residual fragments≤3 mm)were 93.7％ and 84.1％,P＞0.05.Conclusions For patients with surgically indicated proximal ureteral calculi,both minimally invasive percutaneous nephrolithotomy in supine position and flexible ureteroscopy are effective and safe therapeutic modalities.Patients treated with flexible ureteroscopy have faster postoperative recovery.

Objective To analyse the effectiveness of the preoperative 3-dimensional conformal radiotherapy for large nephroblastoma up to 10 centimeters in diameter,and to investigate more effective preoperative therapies for intermediate and advanced nephroblastoma.Methods 32 cases of nephroblastoma were treated with preoperative radiotherapy with a dose fractionation as follows:150-200 cGy/fraction,5 fraction/week,the total dose of 1 000-2 000cGy,the mean dose of 1 600 cGy.During the radiotherapy,the B ultrasonic examination and CT were performed weekly to measure the variation of tumor volumes.The time of operation were determined based on the overall health status of patients,the shrinkage of tumor,and adhesions between tumor and adjacent vital organs.Radiontherapy was terminated one week before operation.4 patients who were found tumor adhered to normal tissues around kidney during operation were placed silver clip,and were given postoperative radiotherapy with additional dose of 1 000-2 000 cGy and the mean dose of 1 200 cGy.Results The median tumor reduction rate was 37 ％.The effective rate of preoperative radiotherapy was 100 ％.The complete resection rate was 87.5 ％.2-years tumor-free survival rates was 84.4 ％ and 5-years was 78.1％.There was no surgery-related death.Conclusion Preoperative 3-dimensional conformal radiotherapy reduces tumor volume,and raises resection and survival rate.

Objective To summarize the research status and hotspots of Wumei Pills;To provide ideas and methods for the follow-up research of Wumei Pills.Methods Related literature about Wumei Pills was retrieved from CNKI,VIP,Wanfang Data and CBM from the establishment of the databases to January 12,2023.The publication time,author,author unit and keywords were collected and extracted through NoteExpress 3.0 software to manage bibliographic data.VOSviewer 1.6.18 software was used to conduct co-occurrence and clustering analysis,and construct keyword time superposition network.Results After screening,a total of 2 105 articles were included,involving 3 554 authors,such as Yan Shuguang,Fan Heng,and Hui Yi.They were from 1 135 units,such as Dongzhimen Hospital of Beijing University of Chinese Medicine,Shandong University of Traditional Chinese Medicine and Beijing University of Chinese Medicine.The included articles contained 2 565 keywords,which appeared 7 061 times,and the research involved 4 main directions:digestive system diseases(ulcerative colitis),study on TCM classics(Shang Han Za Bing Lun),medical cases and experience,and biliary ascariasis.The hotspots of Wumei Pills were scattered in recent years.Six meridian disease to appear,opening and closing pivots,intestinal microbiota,serum inflammatory factors and insomnia were research hotspots in recent 3 years.Conclusion The research of Wumei Pills mainly focus on the research of digestive system diseases,TCM classics,medical cases and experience,and biliary ascariasis.Theoretical research of TCM and mechanism research possibly become new hotspots of this field.