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THEORETICAL BASIS AND GENERAL OPTIMAL FORMULATIONS OF ISOPARAMETRIC GENERALIZED HYBRID/MIXED ELEMENT MODEL FOR IMPROVED STRESS ANALYSIS 被引量:2
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作者 张武 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第3期277-288,共12页
By the modified three-field Hu-Washizu principle, this paper establishes a theoretical founda- tion and general convenient formulations to generate convergent stable generalized hybrid/mixed cle- ment (GH/ME) model wh... By the modified three-field Hu-Washizu principle, this paper establishes a theoretical founda- tion and general convenient formulations to generate convergent stable generalized hybrid/mixed cle- ment (GH/ME) model which is invariant with respect to coordinate, insensitive to geometric distortion and suitable for improved stress computation. In the two proposed formulations, the stress equilibrium and orthogonality constraints are imposed through incompatible displacement and internal strain modes respectively. The proposed model by the general formulations in this paper is characterized by including as- sumed stress/strain, assumed stress, variable-node, singular, compatible and incompatible GH/ME models. When using regular meshes or the constant values of the isoparametric Jacobian Det in the assumed strain in- terpolation, the incompatible GH/ME model degenerates to the hybrid/mixed element model. Both general and concrete guidelines for the optimal selection of element shape functions are suggested. By means of the GH/ME theory in this paper, a family of new GH/ME can be and have been easily constructed. The software can also be developed conveniently because all the standard subroutines for the corresponding isoparametric displacement elements can be utilized directly. 展开更多
关键词 generalized hybrid/mixed model element formulation equilibrium orthogonality least energy fit convergence stability coordinate invariance distortion insensitivity accuracy
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A POTENTIAL-HYBRID/MIXED FINITE ELEMENT SCHEME FOR ANALYSIS OF PLATES AND CYLINDRICAL SHELLS
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作者 陈大鹏 潘亦甦 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第9期809-820,共12页
Based on the potential-hybrid/mixed finite element scheme, 4-node quadrilateral plate-bending elements MP4, MP4a and cylindrical shell element MCS4 are derived with, the inclusion of splitting rotations. All these ele... Based on the potential-hybrid/mixed finite element scheme, 4-node quadrilateral plate-bending elements MP4, MP4a and cylindrical shell element MCS4 are derived with, the inclusion of splitting rotations. All these elements demonstrate favorable convergence behavior over the existing counterparts, free from spurious kinematic mode's and do not exhibit locking phenomenon in thin platef shell limit. Inter-connections between the existing modified variational functionals for the use of formulating C0-and C1-continuous elements are also indicated. Important particularizations of the present scheme include Prathop's consistent field formulation, the RIT/SRIT-compatible displacement model and so on. 展开更多
关键词 potential-hybrid/mixed F.E. consistent field R. I. T. plate cylindrical shell
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Hybrid Effects on MHD Mixed Convective Boundary Layer Flow through a Sloped Plate in Existence of Nanofluid-Saturated Porous Medium
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作者 Md. Nasir Uddin Abdul Halim Bhuiyan +1 位作者 Zahurul Islam Tahmina Tahrim 《Journal of Applied Mathematics and Physics》 2024年第9期3037-3052,共16页
This study examines the effects of heat, mass, and boundary layer assumptions-based nanoparticle characteristics on the hybrid effects of using MHD in conjunction with mixed convective flow through a sloped vertical p... This study examines the effects of heat, mass, and boundary layer assumptions-based nanoparticle characteristics on the hybrid effects of using MHD in conjunction with mixed convective flow through a sloped vertical pore plate in the existence of medium of porous. Physical characteristics such as thermo-diffusion, injection-suction, and viscous dissipation are taken into consideration, in addition to an equally distributed magnetic force utilized as well in the completely opposite path of the flow. By means of several non-dimensional transformations, the momentum, energy, concentration, and nanoparticle volume fraction equations under investigation are converted in terms of nonlinear boundary layer equations and computationally resolved by utilizing the sixth-order Runge-Kutta strategy in combination together with the iteration of Nachtsheim-Swigert shooting procedure. By contrasting the findings produced for a few particular examples with those found in the published literature, the correctness of the numerical result is verified, and a rather good agreement is found. Utilizing various ranges of pertinent factors, computing findings are determined not only regarding velocity, temperature, and concentration as well as nanoparticle fraction of volume but also concerning with local skin-friction coefficient, local Nusselt and general Sherwood numbers associated with nanoparticle Sherwood number. The findings of the study demonstrate that increasing the fluid suction parameter decreases the velocity and temperature of the flow field in conjunction with concentration and has a variable impact on the nanoparticle fraction of volume, despite an increasing behavior in the local skin friction coefficient and local Nusselt as well as general Sherwood numbers and an increasing behavior in the local nanoparticle Sherwood number. Furthermore, enhancing a Schmidt number leads to a reduction in the local nanoparticle Sherwood number and a rise in the nanoparticle proportion of volume. Along with concentration, it also reduces temperature and velocity. However, it also raises the local Sherwood and Nusselt numbers and reduces the local skin friction coefficient. 展开更多
关键词 hybrid Effects mixed Convection MHD NANOFLUID Viscous Dissipation
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Ag-integrated mixed metallic Co-Fe-Ni-Mn hydroxide composite as advanced electrode for high-performance hybrid supercapacitors
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作者 Anki Reddy Mule Bhimanaboina Ramulu +2 位作者 Shaik Junied Arbaz Anand Kurakula Jae Su Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期579-591,I0013,共14页
Direct growth of redox-active noble metals and rational design of multifunctional electrochemical active materials play crucial roles in developing novel electrode materials for energy storage devices.In this regard,s... Direct growth of redox-active noble metals and rational design of multifunctional electrochemical active materials play crucial roles in developing novel electrode materials for energy storage devices.In this regard,silver(Ag)has attracted great attention in the design of efficient electrodes.Inspired by the house/building process,which means electing the right land,it lays a strong foundation and building essential columns for a complex structure.Herein,we report the construction of multifaceted heterostructure cobalt-iron hydroxide(CFOH)nanowires(NWs)@nickel cobalt manganese hydroxides and/or hydrate(NCMOH)nanosheets(NSs)on the Ag-deposited nickel foam and carbon cloth(i.e.,Ag/NF and Ag/CC)substrates.Moreover,the formation and charge storage mechanism of Ag are described,and these contribute to good conductive and redox chemistry features.The switching architectural integrity of metal and redox materials on metallic frames may significantly boost charge storage and rate performance with noticeable drop in resistance.The as-fabricated Ag@CFOH@NCMOH/NF electrode delivered superior areal capacity value of 2081.9μA h cm^(-2)at 5 mA cm^(-2).Moreover,as-assembled hybrid cell based on NF(HC/NF)device exhibited remarkable areal capacity value of 1.82 mA h cm^(-2)at 5 mA cm^(-2)with excellent rate capability of 74.77%even at 70 mA cm^(-2)Furthermore,HC/NF device achieved maximum energy and power densities of 1.39 mW h cm^(-2)and 42.35 mW cm^(-2),respectively.To verify practical applicability,both devices were also tested to serve as a self-charging station for various portable electronic devices. 展开更多
关键词 Current collectors Redox-active silver Transition metal-hydroxides Electrochemical performance hybrid supercapacitor
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Mixed neuroendocrine non-neuroendocrine neoplasms in gastroenteropancreatic tract 被引量:3
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作者 Sebastián Díaz-López Jerónimo Jiménez-Castro +2 位作者 Carlos Enrique Robles-Barraza Carlos Ayala-de Miguel Manuel Chaves-Conde 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1166-1179,共14页
Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic tract.They are composed of a neuroendocrine(NE)and a non-NE com... Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are a hetero-geneous group of malignant neoplasms that can settle in the gastroenteropan-creatic tract.They are composed of a neuroendocrine(NE)and a non-NE compo-nent in at least 30%of each tumour.The non-NE component can include different histological combinations of glandular,squamous,mucinous and sarcomatoid phenotypes,and one or both of the components can be low-or high grade malignant.Recent changes in the nomenclature of these neoplasms might lead to great deal of confusion,and the lack of specific clinical trials is the main reason why their management is difficult.The review aims to clarify the definition of MiNEN and analyze available evidence about their diagnosis and treatment options according to their location and extension through careful analysis of the available data.It would be important to reach a general consensus on their diagnosis in order to construct a classification that remains stable over time and facilitates the design of clinical trials that,due to their low incidence,will require long recruitment periods. 展开更多
关键词 mixed neuroendocrine non-neuroendocrine neoplasms mixed adenoneuroendocrine carcinomas mixed tumours Gastroenteropancreatic Treatment Etiology Diagnosis
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Mixed neuroendocrine and adenocarcinoma of gastrointestinal tract:A complex diagnosis and therapeutic challenge 被引量:1
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作者 Santosh Shenoy 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2295-2299,共5页
In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction.Mixed neuroendocrine and non-neuroendocrine neoplasms of the ga... In this editorial we comment on the manuscript describing a case of adenocarcinoma mixed with a neuroendocrine carcinoma of the gastroesophageal junction.Mixed neuroendocrine and non-neuroendocrine neoplasms of the gastrointestinal system are rare heterogeneous group of tumors characterized by a high malignant potential,rapid growth,and poor prognosis.Due to the rarity of these cancers,the standard therapy is poorly defined.The diagnosis of these tumors is based on combination of morphological features,immunohistochemical and neuroendocrine and epithelial cell markers.Both endocrine and epithelial cell components can act independently of each other and thus,careful grading of each component separately is required.These cancers are aggressive in nature and the potential of each component has paramount importance in the choice of treatment and response.Regardless of the organ of origin,these tumors portend poor prognosis with increased proportion of neuroendocrine component.Multidisciplinary services and strategies are required for the management of these mixed malignancies to provide the best oncological outcomes.The etiopathogenesis of these mixed tumors remains obscure but poses interesting question.We briefly discuss a few salient points in this editorial. 展开更多
关键词 mixed adenocarcinoma and neuroendocrine carcinoma mixed neuroendocrine and non-neuroendocrine neoplasm mixed adeno-neuroendocrine cancer Cell reprograming Tumor plasticity
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Mixed neuroendocrine non-neuroendocrine tumors:The quest for evidence 被引量:1
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作者 Mauro Cives Camillo Porta Raffaele Palmirotta 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第12期4532-4536,共5页
Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are rare mixed tumors containing both neuroendocrine and non-neuroendocrine components that occupy at least 30%of the whole tumor.Biologically,both components a... Mixed neuroendocrine non-neuroendocrine neoplasms(MiNENs)are rare mixed tumors containing both neuroendocrine and non-neuroendocrine components that occupy at least 30%of the whole tumor.Biologically,both components appear to derive from an identical cellular precursor undergoing early dual differentiation or late transdifferentiation.While our understanding of MiNENs has improved in recent years,many areas of uncertainty remain.In this context,setting diagnostic criteria capable of capturing the continuum of disease biology while providing clinically meaningful information in terms of prognosis and response to treatments appears vital to advance the field and improve patients’outcomes.Evidence is needed to generate robust classification schemes,and multi-institutional cooperation will likely play a crucial role in building adequately powered cohorts to address some of the most pressing questions discussed in this Editorial.What is the minimum representation for each component needed to define MiNENs?How can the epidemiology of MiNENs change according to different diagnostic definitions?How can we generate the clinical evidence nee-ded to optimize the management of MiNENs? 展开更多
关键词 mixed neuroendocrine non-neuroendocrine neoplasms Neuroendocrine neoplasm Neuroendocrine carcinoma mixed tumors DIGESTIVE Gastroenteropancreatic
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Dendroclimatological study of Sabina saltuaria and Abies faxoniana in the mixed forests of the Qionglai Mountains,eastern Tibetan Plateau 被引量:1
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作者 Teng Li Jianfeng Peng +3 位作者 Tsun Fung Au Jingru Li Jinbao Li Yue Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期72-82,共11页
Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-e... Tree-ring chronologies were developed for Sabina saltuaria and Abies faxoniana in mixed forests in the Qionglai Mountains of the eastern Tibetan Plateau.Climate-growth relationship analysis indicated that the two co-exist-ing species reponded similarly to climate factors,although S.saltuaria was more sensitive than A.faxoniana.The strong-est correlation was between S.saltuaria chronology and regional mean temperatures from June to November.Based on this relationship,a regional mean temperature from June to November for the period 1605-2016 was constructed.Reconstruction explained 37.3%of the temperature variance during th period 1961-2016.Six major warm periods and five major cold periods were identified.Spectral analysis detected significant interannual and multi-decadal cycles.Reconstruction also revealed the influence of the Atlantic Multi-decadal Oscillation,confirming its importance on climate change on the eastern Tibetan Plateau. 展开更多
关键词 Tree-ring analysis mixed forests DENDROCLIMATOLOGY Qionglai Mountains
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Amino-functionalized UiO-66-doped mixed matrix membranes with high permeation performance and fouling resistance 被引量:1
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作者 Yi Zhang Di Liu +6 位作者 Zhaoli Wang Junjian Yu Yanyin Cheng Wenjing Li Zhe Wang Hongzhe Ni Yuchao Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期68-77,共10页
For the reduction of bovine serum proteins from wastewater,a novel mixed matrix membrane was prepared by functionalizing the substrate material polyaryletherketone(PAEK),followed by carboxyl groups(C-SPAEKS),and then ... For the reduction of bovine serum proteins from wastewater,a novel mixed matrix membrane was prepared by functionalizing the substrate material polyaryletherketone(PAEK),followed by carboxyl groups(C-SPAEKS),and then adding amino-functionalized UiO-66-NH_(2)(Am-UiO-66-NH_(2)).Aminofunctionalization of UiO-66 was accomplished by melamine,followed by an amidation reaction to immobilize Am-UiO-66-NH_(2),which was immobilized on the surface of the membrane as well as in the pore channels,which enhanced the hydrophilicity of the membrane surface while increasing the negative potential of the membrane surface.This nanoparticle-loaded ultrafiltration membrane has good permeation performance,with a pure water flux of up to 482.3 L·m^(-2)·h^(-1) for C-SPAEKS/AmUiO-66-NH_(2) and a retention rate of up to 98.7%for bovine serum albumin(BSA)-contaminated solutions.Meanwhile,after several hydrophilic modifications,the flux recovery of BSA contaminants by this series of membranes increased from 56.2%to 80.55%of pure membranes.The results of ultra-filtration flux time tests performed at room temperature showed that the series of ultrafiltration membranes remained relatively stable over a test time of 300 min.Thus,the newly developed mixed matrix membrane showed potential for high efficiency and stability in wastewater treatment containing bovine serum proteins. 展开更多
关键词 ULTRAFILTRATION mixed matrix membranes Amino functionalization Hydrophilic modification Negatively charged
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A mixed-coordination electron trapping-enabled high-precision touch-sensitive screen for wearable devices 被引量:1
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作者 Xi Zhang Junchi Ma +5 位作者 Hualin Deng Jinming Zhong Kaichen Xu Qiang Wu Bo Wen Dongfeng Diao 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期413-427,共15页
Touch-sensitive screens are crucial components of wearable devices.Materials such as reduced graphene oxide(rGO),carbon nanotubes(CNTs),and graphene offer promising solutions for flexible touch-sensitive screens.Howev... Touch-sensitive screens are crucial components of wearable devices.Materials such as reduced graphene oxide(rGO),carbon nanotubes(CNTs),and graphene offer promising solutions for flexible touch-sensitive screens.However,when stacked with flexible substrates to form multilayered capacitive touching sensors,these materials often suffer from substrate delamination in response to deformation;this is due to the materials having different Young’s modulus values.Delamination results in failure to offer accurate touch screen recognition.In this work,we demonstrate an induced charge-based mutual capacitive touching sensor capable of high-precision touch sensing.This is enabled by electron trapping and polarization effects related to mixed-coordinated bonding between copper nanoparticles and vertically grown graphene nanosheets.Here,we used an electron cyclotron resonance system to directly fabricate graphene-metal nanofilms(GMNFs)using carbon and copper,which are firmly adhered to flexible substrates.After being subjected to 3000 bending actions,we observed almost no change in touch sensitivity.The screen interaction system,which has a signal-to-noise ratio of 41.16 dB and resolution of 650 dpi,was tested using a handwritten Chinese character recognition trial and achieved an accuracy of 94.82%.Taken together,these results show the promise of touch-sensitive screens that use directly fabricated GMNFs for wearable devices. 展开更多
关键词 Flexible touch-sensitive screen Graphene-metal nanofilms mixed coordination Wearable device
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Recent progress in ternary mixed matrix membranes for CO_(2) separation 被引量:1
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作者 Zikang Qin Yulei Ma +13 位作者 Jing Wei Hongfang Guo Bangda Wang Jing Deng Chunhai Yi Nanwen Li Shouliang Yi Yi Deng Wentao Du Jian Shen Wenju Jiang Lu Yao Lin Yang Zhongde Dai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期831-858,共28页
Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,s... Mixed matrix membranes(MMMs)could combine the advantages of both polymeric membranes and porousfillers,making them an effective alternative to conventional polymer membranes.However,interfacial incompatibility issues,such as the presence of interfacial voids,hardening of polymer chains,and blockage of micropores by polymers between common MMMsfillers and the polymer matrix,currently limit the gas sep-aration performance of MMMs.Ternary phase MMMs(consisting of afiller,an additive,and a matrix)made by adding a third compound,usually functionalized additives,can overcome the structural problems of binary phase MMMs and positively impact membrane separation performance.This review introduces the structure and fabrication processes for ternary MMMs,categorizes various nanofillers and the third component,and summarizes and analyzes in detail the CO_(2) separation performance of newly developed ternary MMMs based on both rubbery and glassy polymers.Based on this separation data,the challenges of ternary MMMs are also discussed.Finally,future directions for ternary MMMs are proposed. 展开更多
关键词 CO_(2) separation mixed matrix membranes Ternary phase
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Synergistic anionic/zwitterionic mixed surfactant system with high emulsification efficiency for enhanced oil recovery in low permeability reservoirs 被引量:1
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作者 Hai-Rong Wu Rong Tan +6 位作者 Shi-Ping Hong Qiong Zhou Bang-Yu Liu Jia-Wei Chang Tian-Fang Luan Ning Kang Ji-Rui Hou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期936-950,共15页
Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant... Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs. 展开更多
关键词 Anionic/zwitterionic mixed surfactant system EMULSIFICATION Synergistic effect Low permeability reservoir Enhanced oil recovery
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Analysis of factors impacting postoperative pain and quality of life in patients with mixed hemorrhoids:A retrospective study 被引量:1
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作者 Xiao-Wen Sun Jing-Yi Xu +3 位作者 Chang-Zhen Zhu Si-Jia Li Lu-Jia Jin Zhi-Dong Zhu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第3期731-739,共9页
BACKGROUND Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery.They are venous clusters formed by con-gestion,expansion,and flexion of the venous plexus in ... BACKGROUND Hemorrhoids are among the most common and frequently encountered chronic anorectal diseases in anorectal surgery.They are venous clusters formed by con-gestion,expansion,and flexion of the venous plexus in the lower part of the rec-tum.Mixed hemorrhoids bleed easily and recurrently,and this can result in severe anemia.Hence,they may have a negative effect on the health of the patient and surgical treatment is required.Milligan-Morgan hemorrhoidectomy has been widely used since 1937 for the treatment of grade III and IV hemorrhoids.How-ever,most patients experience different degrees of postoperative pain that may cause anxiety.with mixed hemorrhoids post-surgery.METHODS The clinical data of patients with mixed hemorrhoids who underwent Milligan-Morgan hemorrhoidectomy were collected retrospectively.The basic character-istics of the enrolled patients with mixed hemorrhoids were recorded,and based on the Goligher clinical grading system,the hemorrhoids were classified as grades III or IV.The endpoint of this study was the disappearance of pain in all patients.Quantitative data were presented as mean±SD,such as age,pain score,and QoL score.Student’s t-test was used to compare the groups.RESULTS A total of 164 patients were enrolled.The distribution of the visual analog scale pain scores of all patients at 3,7,14 and 28 d after surgery showed that post-surgery pain was significantly reduced with the passage of time.Fourteen days after the operation,the pain had completely disappeared in some patients.Twenty-eight days after the surgery,none of the patients experienced any pain.Comparing the World Health Or-ganization Quality of Life-BREF self-reporting questionnaire scores of patients between 14 and 28 d after surgery,we observed that the quality-of-life scores of the patients post-surgery had significantly improved.There were six items that were compared at 14-and 28-d post-surgery.The mean QoL score 28 d after surgery(4.79±0.46)was higher than that at 14 d post-surgery(3.79±0.57).The mean health condition score 28 d after surgery(4.80±0.41)was also higher than that at 14 d post-surgery(4.01±0.62).The mean physical health score 28 d after surgery(32.10±2.96)was significantly higher than that at 14 d post-surgery(23.41±2.85).The mean psychological health score 28 d after surgery(27.22±1.62)was significantly higher than that at 14 d post-surgery(21.37±1.70).The mean social relations score 28 d after surgery(12.21±1.59)was significantly higher than that at 14 d post-surgery(6.32±1.66).The mean surrounding environment score 28 d after surgery(37.13±2.88)was significantly higher than that at 14 d post-surgery(28.42±2.86).The differences in quality-of-life scores at day 14 and day 28 post-surgery were ob-served to be statistically significant(P<0.001).CONCLUSION Milligan-Morgan hemorrhoidectomy can significantly improve the postoperative QoL of patients.Age,sex,and the number of surgical resections were important factors influencing Milligan-Morgan hemorrhoidectomy. 展开更多
关键词 HEMORRHOIDS mixed hemorrhoids Milligan organ hemorrhoidectomy Postoperative pain Quality of life Anesthesia mode
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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu
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作者 Wanxia Peng Tongqing Song +5 位作者 Hu Du Feng Wang Fuping Zeng Yang Wang Shulin Chen Yinzhu Chen 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期81-94,共14页
Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communiti... Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand. 展开更多
关键词 Diversity Abundant taxa Rare taxa THINNING mixed stand
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Performance analysis of the tight combination of GPS, BDS, GALILEO, and QzsS mixed frequencies signals
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作者 Yu Han Fangjun Qin +3 位作者 Xugang Lian Shengliang Wang Leiyuan Qian Wenhua Huang 《Geodesy and Geodynamics》 EI CSCD 2024年第4期366-378,共13页
With the gradual development and modernization of satellite navigation systems,using observation information from multi-GNss has become one of the hot-spot issues in recent years.Multi-system loose combinations form d... With the gradual development and modernization of satellite navigation systems,using observation information from multi-GNss has become one of the hot-spot issues in recent years.Multi-system loose combinations form double-difference observation equations within their respective systems,and the positioning effect is improved.However,the interchangeability and compatible interoperability between global navigation satellite systems(GNSS)cannot be truly realized.At the same time,when the number of visible satellites decreases abruptly,the positioning performance deteriorates sharply.This paper focuses on the GNsS multi-system tight combination relative positioning technique,gives a mathe-matical model of multi-system tight combination relative positioning considering differential inter-system bias(DISB),and analyzes the time-varying characteristics of DISB at overlapping and non-overlapping frequencies among GPS/Galileo,GPS/BDS,and GPS/QZSS in terms of receiver brand,tem-perature,and receiver restart.The GNsS tight combination relative positioning performance is verified by static data from Curtin University and dynamic data measured at Taiyuan University of Technology.The results show that compared with loose combination,the ambiguity-fixed rate increases from 62.18%to 97.60%for static data and from 74.97%to 99.53%for dynamic data when the elevation mask angle is 50°,resulting in a significant improvement in positioning performance. 展开更多
关键词 GNSS mix frequencies REDUNDANCY Tightcombination Differential inter-system bias
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Stability Analysis and Performance Evaluation of Additive Mixed-Precision Runge-Kutta Methods
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作者 Ben Burnett Sigal Gottlieb Zachary J.Grant 《Communications on Applied Mathematics and Computation》 EI 2024年第1期705-738,共34页
Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and analyzed.These specially designed methods use reduced precision for the implic... Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and analyzed.These specially designed methods use reduced precision for the implicit computations and full precision for the explicit computations.In this work,we analyze the stability properties of these methods and their sensitivity to the low-precision rounding errors,and demonstrate their performance in terms of accuracy and efficiency.We develop codes in FORTRAN and Julia to solve nonlinear systems of ODEs and PDEs using the mixed-precision additive Runge-Kutta(MP-ARK)methods.The convergence,accuracy,and runtime of these methods are explored.We show that for a given level of accuracy,suitably chosen MP-ARK methods may provide significant reductions in runtime. 展开更多
关键词 mixed precision Runge-Kutta methods Additive methods ACCURACY
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Influences of oscillation on the physical stability and explosion characteristics of solid-liquid mixed fuel
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作者 Chi Zhang Ge Song +2 位作者 Hui Guo Jiafan Ren Chunhua Bai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期191-198,共8页
The stratification phenomenon resulting from differences in the physical properties of solid-liquid components seriously affect the final combustion and explosion characteristics of mixed fuel under the action of osci... The stratification phenomenon resulting from differences in the physical properties of solid-liquid components seriously affect the final combustion and explosion characteristics of mixed fuel under the action of oscillation.The effects of oscillation on the physical stability of mixed fuel with two solid-liquid ratios and three liquid component distribution ratios have been investigated using a self-designed experimental system at oscillation frequencies of 60-300 r/min.The explosion characteristics of mixed fuel before and after oscillation are gained from a 20 L spherical explosion container system.When the mass ratio of liquid components is controlled at 66.9%,64.7%,62.6%the final explosion characteristics are stable,with a maximum difference of only 0.71%.The volume of liquid fuel precipitation increases with increasing oscillation frequency when the mass ratio of liquid components reaches 71.7%,69.6%,67.7%.The fuel explosion overpressure after oscillation decreases with increasing liquid precipitation volume,and the repeatability is poor,with a maximum standard deviation of 82.736,which is much higher than the ratio without stratification.Properly controlling the mass ratio of liquid components of the mixed fuel can effectively combat the impact of oscillation on the physical state and maintain the stability of the final explosion characteristics. 展开更多
关键词 Solid-liquid mixed fuel Physical stability Explosion characteristics
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On the Application of Mixed Models of Probability and Convex Set for Time-Variant Reliability Analysis
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作者 Fangyi Li Dachang Zhu Huimin Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1981-1999,共19页
In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems... In time-variant reliability problems,there are a lot of uncertain variables from different sources.Therefore,it is important to consider these uncertainties in engineering.In addition,time-variant reliability problems typically involve a complexmultilevel nested optimization problem,which can result in an enormous amount of computation.To this end,this paper studies the time-variant reliability evaluation of structures with stochastic and bounded uncertainties using a mixed probability and convex set model.In this method,the stochastic process of a limit-state function with mixed uncertain parameters is first discretized and then converted into a timeindependent reliability problem.Further,to solve the double nested optimization problem in hybrid reliability calculation,an efficient iterative scheme is designed in standard uncertainty space to determine the most probable point(MPP).The limit state function is linearized at these points,and an innovative random variable is defined to solve the equivalent static reliability analysis model.The effectiveness of the proposed method is verified by two benchmark numerical examples and a practical engineering problem. 展开更多
关键词 mixed uncertainty probability model convex model time-variant reliability analysis
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Impacts of bus holding strategy on the performance and pollutant emissions of a two-lane mixed traffic system
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作者 Yanfeng Qiao Ronghan Yao +1 位作者 Baofeng Pan Yu Xue 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期236-248,共13页
This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissio... This paper investigates the impacts of a bus holding strategy on the mutual interference between buses and passenger cars in a non-dedicated bus route,as well as the impacts on the characteristics of pollutant emissions of passenger cars.The dynamic behaviors of these two types of vehicles are described using cellular automata(CA)models under open boundary conditions.Numerical simulations are carried out to obtain the phase diagrams of the bus system and the trajectories of buses and passenger cars before and after the implementation of the bus holding strategy under different probabilities of passenger cars entering a two-lane mixed traffic system.Then,we analyze the flow rate,satisfaction rate,and pollutant emission rates of passenger cars together with the performance of a mixed traffic system.The results show that the bus holding strategy can effectively alleviate bus bunching,whereas it has no significant impact on the flow rate and pollutant emission rates of passenger cars;the flow rate,satisfaction rate,and pollutant emission rates of passenger cars for either the traffic system or for each lane are influenced by the bus departure interval and the number of passengers arriving at bus stops. 展开更多
关键词 mixed traffic flow bus holding strategy cellular automata traffic emissions
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Practical hints for the diagnosis of mixed neuroendocrine-nonneuroendocrine neoplasms of the digestive system
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作者 Paola Mattiolo 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第11期4326-4332,共7页
In this editorial,a comment on the article by Díaz-López et al published in the recent issue of the 2024 is provided.We focus on the practical implications critical for providing a correct and complete diagn... In this editorial,a comment on the article by Díaz-López et al published in the recent issue of the 2024 is provided.We focus on the practical implications critical for providing a correct and complete diagnosis of mixed neuroendocrine-nonneuroendocrine neoplasm(MiNEN)in the gastrointestinal system.The diagnosis of MiNEN begins with the recognition of neuroendocrine features in one component of a biphasic tumor.The non-neuroendocrine counterpart can be virtually represented by any neoplastic type,even though the most frequent histologies are glandular and squamous.However,qualification of the neuroendocrine component requires histological and immunohistochemical confirmation.Neuroendocrine tumors are characterized by a peculiar architectural organization and bland nuclei with granular“salt and pepper”chromatin.Although neuroendocrine carcinomas have multiple and variable presentations,they typically show a solid or organoid architecture.The histological aspect needs to be confirmed by immunohistochemistry,and a diagnosis is confirmed whenever the expression of keratin and neuroendocrine markers is observed.Once both histopathological and immunohistochemical features of neuroendocrine neoplasms are identified,it is important to consider the three major pitfalls of MiNEN diagnostics:(1)Entrapment of neuroendocrine non-neoplastic cells within the tumor mass;(2)Differential diagnosis with amphicrine neoplasms;and(3)Differential diagnosis of tumors that partially express neuroendocrine markers.According to the current guidelines for diagnosing digestive MiNEN,each component must represent at least 30%of the entire neoplastic mass.Although the high-grade histopathological subtype frequently determines disease prognosis,both components can significantly affect prognosis.Thus,if one of the components,either neuroendocrine or non-neuroendocrine,does not fulfill the volumetric criteria,the guidelines still encourage reporting it.These strict criteria are essential for correctly recognizing and characterizing digestive MiNENs.This task is essential because it has prognostic relevance and substantial potential value for guiding further studies in this field.In the future,systematic analyses should be performed to validate or reconsider the current 30%cutoff value. 展开更多
关键词 mixed neuroendocrine-non-neuroendocrine neoplasm Digestive system Neuroendocrine neoplasm IMMUNOHISTOCHEMISTRY
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