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The study of a neutron spectrum unfolding method based on particle swarm optimization combined with maximum likelihood expectation maximization 被引量:1
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作者 Hong-Fei Xiao Qing-Xian Zhang +5 位作者 He-Yi Tan Bin Shi Jun Chen zhi-qiang cheng Jian Zhang Rui Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期149-160,共12页
The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In or... The neutron spectrum unfolding by Bonner sphere spectrometer(BSS) is considered a complex multidimensional model,which requires complex mathematical methods to solve the first kind of Fredholm integral equation. In order to solve the problem of the maximum likelihood expectation maximization(MLEM) algorithm which is easy to suffer the pitfalls of local optima and the particle swarm optimization(PSO) algorithm which is easy to get unreasonable flight direction and step length of particles, which leads to the invalid iteration and affect efficiency and accuracy, an improved PSO-MLEM algorithm, combined of PSO and MLEM algorithm, is proposed for neutron spectrum unfolding. The dynamic acceleration factor is used to balance the ability of global and local search, and improves the convergence speed and accuracy of the algorithm. Firstly, the Monte Carlo method was used to simulated the BSS to obtain the response function and count rates of BSS. In the simulation of count rate, four reference spectra from the IAEA Technical Report Series No. 403 were used as input parameters of the Monte Carlo method. The PSO-MLEM algorithm was used to unfold the neutron spectrum of the simulated data and was verified by the difference of the unfolded spectrum to the reference spectrum. Finally, the 252Cf neutron source was measured by BSS, and the PSO-MLEM algorithm was used to unfold the experimental neutron spectrum.Compared with maximum entropy deconvolution(MAXED), PSO and MLEM algorithm, the PSO-MLEM algorithm has fewer parameters and automatically adjusts the dynamic acceleration factor to solve the problem of local optima. The convergence speed of the PSO-MLEM algorithm is 1.4 times and 3.1 times that of the MLEM and PSO algorithms. Compared with PSO, MLEM and MAXED, the correlation coefficients of PSO-MLEM algorithm are increased by 33.1%, 33.5% and 1.9%, and the relative mean errors are decreased by 98.2%, 97.8% and 67.4%. 展开更多
关键词 Particle swarm optimization Maximum likelihood expectation maximization Neutron spectrum unfolding Bonner spheres spectrometer Monte Carlo method
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Comparison of modified gunsight suture technique and traditional interrupted suture in enterostomy closure
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作者 Chang Chen Xiang Zhang +5 位作者 zhi-qiang cheng Bin-Bin Zhang Xin Li Ke-Xin Wang Yong Dai Yan-Lei Wang 《World Journal of Gastroenterology》 SCIE CAS 2023年第29期4571-4579,共9页
BACKGROUND Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors.However,the ... BACKGROUND Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors.However,the traditional interrupted suturing technique used in enterostomy closure surgery has several issues,including longer surgical incisions and higher incision tension,which can increase the risk of postoperative complications.To address these issues,scholars have proposed the use of a“gunsight suture”technique.This technique involves using a gunsight incision instead of a traditional linear incision,leaving a gap in the center for the drainage of blood and fluid to reduce the risk of infection.Building on this technique,we propose an improved gunsight suture technique.A drainage tube is placed at the lowest point of the incision and close the gap in the center of the gunsight suture,which theoretically facilitates early postoperative mobility and reduces the burden of dressing changes,thereby reducing the risk of postoperative complications.AIM To compare the effectiveness of improved gunsight suture technique with traditional interrupted suture in closing intestinal stomas.METHODS In this study,a retrospective,single-center case analysis was conducted on 270 patients who underwent prophylactic ileostomy closure surgery at the Department of Colorectal Surgery of Qilu Hospital from April 2017 to December 2021.The patients were divided into two groups:135 patients received sutures using the improved gunsight method,while the remaining 135 patients were sutured with the traditional interrupted suture method.We collected data on a variety of parameters,such as operation time,postoperative pain score,body temperature,length of hospital stays,laboratory indicators,incidence of incisional complications,number of wound dressing changes,and hospitalization costs.Non-parametric tests and chi-square tests were utilized for data analysis.RESULTS There were no statistically significant differences in general patient information between the two groups,including the interval between the first surgery and the stoma closure[132(105,184)d vs 134(109,181)d,P=0.63],gender ratio(0.64 vs 0.69,P=0.44),age[62(52,68)years vs 60(52,68)years,P=0.33],preoperative body mass index(BMI)[23.83(21.60,25.95)kg/m²vs 23.12(20.94,25.06)kg/m²,P=0.17].The incidence of incision infection in the improved gunsight suture group tended to be lower than that in the traditional interrupted suture group[(n=2/135,1.4%)vs(n=10/135,7.4%),P<0.05],and the postoperative hospital stay in the improved gunsight suture group was significantly shorter than that in the traditional interrupted suture group[5(4,7)d vs 7(6,8)d,P<0.05].Additionally,the surgical cost in the modified gunsight suture group was slightly lower than that in the traditional suture group[4840(4330,5138)yuan vs 4980(4726,5221)yuan,P>0.05],but there was no significant difference in the total hospitalization cost between the two groups.CONCLUSION In stoma closure surgery,the improved gunsight technique can reduce the incision infection rate,shorten the postoperative hospital stay,reduce wound tension,and provide better wound cosmetic effects compared to traditional interrupted suture. 展开更多
关键词 ENTEROSTOMY Abdominal wound closure technique Suture techniques Surgical wound infection Hospital costs Hospital stay
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Third-Order Nonlinear Optical Responses of Bis(15-crown-5)-stilbenes Binding to One-or Two-Alkali Metal Cation(Li^(+),Na^(+)and K^(+))
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作者 Hai-Ling Yu Tong Zhang +2 位作者 Tian-Liang Ma Bo Hong zhi-qiang cheng 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2023年第5期601-612,I0002,共13页
Bis(15-crown-5)-stilbenes containing crown ether parts have been widely used in a variety of chemical applications,such as cation detectors,because of their ability to selectively bind to alkali metal cations,Bis(15-c... Bis(15-crown-5)-stilbenes containing crown ether parts have been widely used in a variety of chemical applications,such as cation detectors,because of their ability to selectively bind to alkali metal cations,Bis(15-crown-5)-stilbenes and its derivatives with complexation of one-or two-alkali metal cation(Li^(+),Na^(+)and K^(+))have been theoretically investigat-ed by quantum chemistry methods.The coordination of alkali cations results in partial shrinkage of crown ethers,which directly affected natural distribution analysis charges and molecular orbital energy levels.The number of alkali metal ions has significant effects on absorption spectra and mean second hyperpolarizability.When one alkali metal ion was added to the anticonformer of bis(15-crown-5)-stilbene,the absorption spectra were obvious-ly redshifted and the mean second hyperpolarizability values were slightly increased;while two alkali metal ions were added to bis(15-crown-5)-stilbene,the absorption spectra were ob-viously blue shifted and the mean second hyperpolarizability values decreased.On the other hand,as the radius of the alkali ions increased,the mean second hyperpolarizability values of the compounds increased gradually.It is indicated that the mean second hyperpolarizability value is sensitive to the number and radius of the alkali metal cations,thus the third order nonlinear optical response can be used as a signal to detect the number and type of alkali met-al ions. 展开更多
关键词 Bis(crown)-stilbene Cation detector Metal cation Quantum chemistry Sec-ond hyperpolarizability
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Vascular anatomy of inferior mesenteric artery in laparoscopic radical resection with the preservation of left colic artery for rectal cancer 被引量:18
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作者 Ke-Xin Wang zhi-qiang cheng +2 位作者 Zhi Liu Xiao-Yang Wang Dong-Song Bi 《World Journal of Gastroenterology》 SCIE CAS 2018年第32期3671-3676,共6页
AIM To investigate the vascular anatomy of inferior mesenteric artery(IMA) in laparoscopic radical resection with the preservation of left colic artery(LCA) for rectal cancer. METHODS A total of 110 patients with rect... AIM To investigate the vascular anatomy of inferior mesenteric artery(IMA) in laparoscopic radical resection with the preservation of left colic artery(LCA) for rectal cancer. METHODS A total of 110 patients with rectal cancer who underwent laparoscopic surgical resection with preservation of the LCA were retrospectively reviewed. A 3 D vascular reconstruction was performed before each surgical procedure to assess the branches of the IMA. During surgery, the relationship among the IMA, LCA, sigmoid artery(SA) andsuperior rectal artery(SRA) was evaluated, and the length from the origin of the IMA to the point of branching into the LCA or common trunk of LCA and SA was measured. The relationship between inferior mesenteric vein(IMV) and LCA was also evaluated.RESULTS Three vascular types were identified in this study. In type A, LCA arose independently from IMA(46.4%, n = 51); in type B, LCA and SA branched from a common trunk of the IMA(23.6%, n = 26); and in type C, LCA, SA, and SRA branched at the same location(30.0%, n = 33). The difference in the length from the origin of IMA to LCA was not statistically significant among the three types. LCA was located under the IMV in 61 cases and above the IMV in 49 cases. CONCLUSION The vascular anatomy of the IMA and IMV is essential for laparoscopic radical resection with preservation of the LCA for rectal cancer. To recognize different branches of the IMA is necessary for the resection of lymph nodes and dissection of vessels. 展开更多
关键词 INFERIOR MESENTERIC ARTERY Left COLIC ARTERY RECTAL cancer LAPAROSCOPIC
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Khubchandani's procedure combined with stapled posterior rectal wall resection for rectocele 被引量:5
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作者 Yi Shao Yong-Xing Fu +3 位作者 Qing-Fa Wang zhi-qiang cheng Guang-Yong Zhang San-Yuan Hu 《World Journal of Gastroenterology》 SCIE CAS 2019年第11期1421-1431,共11页
BACKGROUND Obstructed defecation syndrome(ODS) is a widespread disease in the world.Rectocele is the most common cause of ODS in females. Multiple procedures have been performed to treat rectocele and no procedure has... BACKGROUND Obstructed defecation syndrome(ODS) is a widespread disease in the world.Rectocele is the most common cause of ODS in females. Multiple procedures have been performed to treat rectocele and no procedure has been accepted as the gold-standard procedure. Stapled transanal rectal resection(STARR) has been widely used. However, there are still some disadvantages in this procedure and its effectiveness in anterior wall repair is doubtful. Therefore, new procedures are expected to further improve the treatment of rectocele.AIM To evaluate the efficacy and safety of a novel rectocele repair combining Khubchandani's procedure with stapled posterior rectal wall resection.METHODS A cohort of 93 patients were recruited in our randomized clinical trial and were divided into two different groups in a randomized manner. Forty-two patients(group A) underwent Khubchandani's procedure with stapled posterior rectal wall resection and 51 patients(group B) underwent the STARR procedure.Follow-up was performed at 1, 3, 6, and 12 mo after the operation. Preoperative and postoperative ODS scores and depth of rectocele, postoperative complications, blood loss, and hospital stay of each patient were documented. All data were analyzed statistically to evaluate the efficiency and safety of our procedure.RESULTS In group A, 42 patients underwent Khubchandani's procedure with stapled posterior rectal wall resection and 34 were followed until the final analysis. In group B, 51 patients underwent the STARR procedure and 37 were followed until the final analysis. Mean operative duration was 41.47 ± 6.43 min(group A) vs39.24 ± 6.53 min(group B). Mean hospital stay was 3.15 ± 0.70 d(group A) vs 3.14± 0.54 d(group B). Mean blood loss was 10.91 ± 2.52 mL(group A) vs 10.14 ± 1.86 m L(group B). Mean ODS score in group A declined from 16.50 ± 2.06 before operation to 5.06 ± 1.07 one year after the operation, whereas in group B it was17.11 ± 2.57 before operation and 6.03 ± 2.63 one year after the operation. Mean depth of rectocele decreased from 4.32 ± 0.96 cm(group A) vs 4.18 ± 0.95 cm(group B) preoperatively to 1.19 ± 0.43 cm(group A) vs 1.54 ± 0.82 cm(group B)one year after operation. No other serious complications, such as rectovaginal fistula, perianal sepsis, or deaths, were recorded. After 12 mo of follow-up, 30 patients'(30/34, 88.2%) final outcomes were judged as effective and 4(4/34,11.8%) as moderate in group A, whereas in group B, 30(30/37, 81.1%) patients' outcomes were judged as effective, 5(5/37, 13.5%) as moderate, and 2(2/37,5.4%) as poor.CONCLUSION Khubchandani's procedure combined with stapled posterior rectal wall resection is an effective, feasible, and safe procedure with minor trauma to rectocele. 展开更多
关键词 RECTOCELE RECTAL prolapse Obstructed defecation syndrome Khubchandani’s PROCEDURE Stapled POSTERIOR RECTAL WALL RESECTION Stapled transanal RECTAL RESECTION
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Fast nuclide identification based on a sequential Bayesian method 被引量:3
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作者 Xiao-Zhe Li Qing-Xian Zhang +4 位作者 He-Yi Tan zhi-qiang cheng Liang-Quan Ge Guo-Qiang Zeng Wan-Chang Lai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第12期116-127,共12页
The rapid identification of radioactive substances in public areas is crucial.However,traditional nuclide identification methods only consider information regarding the full energy peaks of the gamma-ray spectrum and ... The rapid identification of radioactive substances in public areas is crucial.However,traditional nuclide identification methods only consider information regarding the full energy peaks of the gamma-ray spectrum and require long recording times,which lead to long response times.In this paper,a novel identification method using the event mode sequence(EMS)information of target radionuclides is proposed.The EMS of a target radionuclide and natural background radiation were established as two different probabilistic models and a decision function based on Bayesian inference and sequential testing was constructed.The proposed detection scheme individually processes each photon.When a photon is detected and accepted,the corresponding posterior probability distribution parameters are estimated using Bayesian inference and the decision function is updated.Then,value of the decision function is compared to preset detection thresholds to obtain a detection result.Experiments on different target radionuclides(137Cs and 60Co)were performed.The count rates of the regions of interest(ROI)in the backgrounds between[651,671],[1154,1186],and[1310,1350]keV were 2.35,5.14,and 0.57 CPS,respectively.The experimental results demonstrate that the average detection time was 6.0 s for 60Co(with an activity of 80400 Bq)at a distance of 60 cm from the detector.The average detection time was 7 s for 137Cs(with an activity of 131000 Bq)at a distance of 90 cm from the detector.The results demonstrate that the proposed method can detect radioactive substances with low activity. 展开更多
关键词 Natural radiation Nuclide identification Sequential testing Nuclear safety
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Edaravone attenuates paraquat-induced lung injury by inhibiting oxidative stress in human type Ⅱalveolar epithelial cells 被引量:8
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作者 zhi-qiang cheng Ji-yuan Han +4 位作者 Peng Sun Yu-ying Weng Jiao Chen Guo-yan Wu Hong-xia Ma 《World Journal of Emergency Medicine》 CAS 2012年第1期55-59,共5页
BACKGROUND:Edaravone(3-methyl-1-penyl-2-pyrazolin-5-one) is a potent free-radical scavenger and has the antioxidant ability to inhibit lipid peroxidation.The study aimed to examine the effect of edaravone on protectin... BACKGROUND:Edaravone(3-methyl-1-penyl-2-pyrazolin-5-one) is a potent free-radical scavenger and has the antioxidant ability to inhibit lipid peroxidation.The study aimed to examine the effect of edaravone on protecting the acute injury of human type II alveolar epithelial cells(A549cells) induced by paraquat(PQ) and the change of production of reactive oxygen species(ROS),malondialdehyde(MDA),superoxide dismutase(SOD).METHODS:A549 cells were cultured and divided into PQ group(group P),edaravone-treated group(group E) and normal control group(group C).The cells in group P were exposed to paraquat(600 umol/L),and the cells in group E were treated with edaravone(100 umol/L) additionally,and no drug intervention was given to the cells in group C.Real-time monitoring by LSCM was used to detect the cell response and the intracellular dynamic change of ROS level in A549 cells after administration of PQ and edaravone.And the levels of SOD and MDA were detected respectively by biochemistry colorimetry.Data were expressed as mean ± standard error of the mean.Statistical analysis was carried out with the soft SPSS 16.0.RESULTS:The concentration of intracellular ROS significantly increased when PQ was given to A549 cells.But after administration of edaravone,the concentration of intracellular ROS was decreased.Compared to the PQ group,the levels of SOD in the edaravone group were significantly increased while the levels of MDA were markedly decreased.CONCLUSIONS:Paraquat can increase the oxidative stress,and induce the lipid peroxidation of A549 cells.Edaravone has the effect to scavenge reactive oxygen species,and to protect against the PQ-induced lung toxicity. 展开更多
关键词 PARAQUAT Intracellular reactive oxygen species EDARAVONE A549 cells POISONING
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Duodenal-jejunal bypass reduces serum ceramides via inhibiting intestinal bile acid-farnesoid X receptor pathway
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作者 zhi-qiang cheng Tong-Ming Liu +4 位作者 Peng-Fei Ren Chang Chen Yan-Lei Wang Yong Dai Xiang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2022年第31期4328-4337,共10页
BACKGROUND Bile acids play an important role in the amelioration of type 2 diabetes following duodenal-jejunal bypass(DJB).Serum bile acids are elevated postoperatively.However,the clinical relevance is not known.Bile... BACKGROUND Bile acids play an important role in the amelioration of type 2 diabetes following duodenal-jejunal bypass(DJB).Serum bile acids are elevated postoperatively.However,the clinical relevance is not known.Bile acids in the peripheral circulation reflect the amount of bile acids in the gut.Therefore,a further investigation of luminal bile acids following DJB is of great significance.AIM To investigate changes of luminal bile acids following DJB.METHODS Salicylhydroxamic acid(SHAM),DJB,and DJB with oral chenodeoxycholic acid(CDCA)supplementation were performed in a high-fat-diet/streptozotocininduced diabetic rat model.Body weight,energy intake,oral glucose tolerance test,luminal bile acids,serum ceramides and intestinal ceramide synthesis were analyzed at week 12 postoperatively.RESULTS Compared to SHAM,DJB achieved rapid and durable improvement in glucose tolerance and led to increased total luminal bile acid concentrations with preferentially increased proportion of farnesoid X receptor(FXR)-inhibitory bile acids within the common limb.Intestinal ceramide synthesis was repressed with decreased serum ceramides,and this phenomenon could be partially antagonized by luminal supplementation of FXR activating bile acid CDCA.CONCLUSION DJB significantly changes luminal bile acid composition with increased proportion FXR-inhibitory bile acids and reduces serum ceramide levels.There observations suggest a novel mechanism of bile acids in metabolic regulation after DJB. 展开更多
关键词 Bariatric surgery Duodenal-jejunal bypass Farnesoid X receptor CERAMIDE Bile acids Liver fat accumulation
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Correction to:Fast nuclide identification based on a sequential Bayesian method
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作者 Xiao-Zhe Li Qing-Xian Zhang +4 位作者 He-Yi Tan zhi-qiang cheng Liang-Quan Ge Guo-Qiang Zeng Wan-Chang Lai 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期29-29,共1页
Correction to:NUCL SCI TECH(2021)32:143 https://doi.org/10.1007/s41365-021-00982-z In the original article,the funding information were missing and in this correction the funding information is given below:Funding Thi... Correction to:NUCL SCI TECH(2021)32:143 https://doi.org/10.1007/s41365-021-00982-z In the original article,the funding information were missing and in this correction the funding information is given below:Funding This work was supported by the National Natural science Foundation of China(No.41774190),the Special-funded program on national key scientific instruments and equipment development(No.2017YFC0602105),and the Department of Science and Technology of Sichuan Province(No.2020JDRC0109). 展开更多
关键词 funded CORRECTION FUNDING
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Growth hormone improves insulin resistance in visceral adipose tissue after duodenal-jejunal bypass by regulating adiponectin secretion
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作者 Zi-Tian Liu Guang-Wei Yang +9 位作者 Xiang Zhao Shuo-Hui Dong Yang Jiao Zheng Ge Ao Yu Xi-Qiang Zhang Xin-Zhen Xu zhi-qiang cheng Xiang Zhang Ke-Xin Wang 《World Journal of Diabetes》 SCIE 2024年第6期1340-1352,共13页
BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not clear.AIM To study the morphological and functional changes in adipose tissue after DJB and explore the poten... BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not clear.AIM To study the morphological and functional changes in adipose tissue after DJB and explore the potential mechanisms contributing to postoperative insulin sensitivity improvement of adipose tissue in a diabetic male rat model.METHODS DJB and sham surgery was performed in a-high-fat-diet/streptozotocin-induced diabetic rat model.All adipose tissue was weighed and observed under microscope.Use inguinal fat to represent subcutaneous adipose tissue(SAT)and mesangial fat to represent visceral adipose tissue.RNA-sequencing was utilized to evaluate gene expression alterations adipocytes.The hematoxylin and eosin staining,reverse transcription-quantitative polymerase chain reaction,western blot,and enzyme-linked immunosorbent assay were used to study the changes.Insulin resistance was evaluated by immunofluorescence.RESULTS After DJB,whole body blood glucose metabolism and insulin sensitivity in adipose tissue improved.Fat cell volume in both visceral adipose tissue(VAT)and SAT increased.Compared to SAT,VAT showed more significantly functional alterations after DJB and KEGG analysis indicated growth hormone(GH)pathway and downstream adiponectin secretion were involved in metabolic regulation.The circulating GH and adiponectin levels and GH receptor and adiponectin levels in VAT increased.Cytological experiment showed that GH stimulated adiponectin secretion and improve insulin sensitivity.CONCLUSION GH improves insulin resistance in VAT in male diabetic rats after receiving DJB,possibly by increasing adiponectin secretion. 展开更多
关键词 Growth hormone Insulin resistance Bariatric surgery Adipose tissue Adiponectin
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