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International Journal of Minerals,Metallurgy and Materials 2019年第8期26卷 1005-1012页

作者： Ghasem Jamali Salman Nourouzi Roohollah Jamaati Department of Materials Engineering Babol Noshirvani University of Technology

In the present work,the friction stir back extrusion(FSBE)process was used as a novel method for the fabrication of AA6063 aluminum alloy *** electron microscopy(SEM)equipped with energy dispersive spectroscopy(EDS),tensile and hardness tests were *** FSBE via the rotational speed of 475 r/min resulted in fine equiaxed grains,and the mean grain size decreased from 179.0μm to 15.5μm due to the occurrence of dynamic recrystallization(DRX).Heat generated by the FSBE changed the size and volume fraction of the Mg2Si precipitated *** minimum particle size and maximum volume fraction obtained in the sample were processed by rotational speeds of 475 and 600 r/min,*** 475-r/min sample had the maximum hardness value due to having the lowest grain size(i.e.,15.5μm)and the presence of many fine Mg2Si precipitates in the aluminum *** increasing rotational speed up to 600 r/min,the hardness decreased,owing to the growth of both grains and *** FSBE process with a rotational speed of 475 r/min increased the tensile strength(from 150 to 209 MPa)and ductility(from 21.0%to 30.2%)simultaneously.

关键词： aluminum alloys friction stir back extrusion microstructure mechanical properties

back Pressure Characteristics for Turbine Channel of External-Parallel TBCC Inlet

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第5期36卷 808-816页

作者： SUN Bo XIANG Cuiling ZHUO Changfei Department of Aerospace Engineering Nanjing University of Science and TechnologyNanjing 210094P.R.China Shanxi North Xing'an Chemical Indutry Co. Ltd.Taiyuan 030008P.R.China.

For investigating the back pressure characteristics of turbine channel of an external-parallel turbine-based combined cycle(TBCC)inlet during the mode transition with the freestream air Mach number of 1.8,wind tunnel tests and numerical simulations are carried *** results show that the critical back pressure of the turbine channel decreases linearly with the decrease of the open degree of splitter *** turbine channel has self-starting capacity when the open degree of the turbine channel is 100%.The total pressure recovery coefficient increases with the increase of back pressure when turbine channel is at supercritical and critical *** mass capture ratio,total pressure recovery coefficient and outlet pressure ratio decrease obviously when turbine channel is at subcritical *** of the research would provide scheme reference and technology storage for TBCC propulsion evolution.

关键词： turbine-based combined cycle inlet turbine channel mode transition back pressure wind tunnel test

Influence of rooftop telecommunication tower on set back-step back building resting on different ground slopes

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 351-362页

作者： Amit Thakur Deepankar Kumar Ashish Surender Kumar Verma Civil Engineering Department Kurukshetra University Civil Engineering Department Maharaja Agrasen Institute of Technology Maharaja Agrasen University Civil Engineering Department Punjab Engineering College (Deemed to be University)

In the hilly region due to scarcity of the plain area, buildings like set back-step back are more often used and also as a big surge in the telecommunication industries, rooftop tower adaptation is very common story nowadays. In the present study an analogy has been drawn to find out the influence of the rooftop telecommunication tower on the setback-step back building resting on ground at 20° and 30° slopes. A dynamic analysis has been performed and compared on the 4 legged angled section telecommunication tower which is located on the roof top of set back-step back building by varying positions of tower with the existing host structure built up on ground slope of 20° and 30° in both directions(X and Y).

关键词： rooftop telecommunication tower set back-step back building response spectrum analysis steel, RC frame, earthquake SAP2000

back analysis of mechanical parameters of roller compacted concrete dam

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Science China(Technological Sciences) 2010年第3期53卷 848-853页

作者： GU ChongShi 1,2,3,LI Bo 1,XU GuangLei 4 &YU Hong 1,2,3 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2College of Water Conservancy Hydropower,Hohai University,Nanjing 210098,China 3National Engineering Research Center of Water Resources Engineering Safety,Efficient Utilization and Nanjing 210098,China 4 Nanjing Hydraulic Research Institute,Nanjing 210029,China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing China College of Water Conservancy Hydropower Hohai University Nanjing China National Engineering Research Center of Water Resources Engineering Safety Efficient Utilization and Nanjing Nanjing China Nanjing Hydraulic Research Institute Nanjing China

In view of the diversity and complexity of mechanical parameters of roller compacted concrete dam(RCCD),the uniform design method,partial least-squares regression(PLS)and least squares support vector machine(LSSVM)were applied to the back analysis of RCCD with the use of the complex nonlinear relationship between dam mechanical parameters and dam *** the process of back analysis,the initial samples of parameters were designed with uniform design ***,a transversely isotropic model of RCCD was established by *** *** this model,training samples of LSSVM model could be *** then,the complex nonlinear relationship between relative values of hydraulic components of dam displacements and mechanical parameters was ***,actual relative values of dam hydraulic components are isolated from the measured data of dam displacements by using *** inputting the isolated relative values into LSSVM model,the back analysis values of RCCD mechanical parameters can be *** example analysis showed that mechanical parameters obtained by the above-mentioned back analysis method are reasonable,and the back analysis method is feasible.

关键词： roller compacted concrete dam mechanical parameters back analysis

Effect of acupressure on postpartum low back pain, salivary cortisol, physical limitations, and depression: a randomized controlled pilot study

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Journal of Traditional Chinese Medicine 2020年第1期40卷 128-136页

作者： Cheng Hsuesh-Yu Carol Shieh Wu Bei-Yu Cheng Yu-Fen Department of Nursing Kaohsiung Chang Gung Memorial HospitalKaohsiung 80830Taiwan China Department of Community and Health Systems Indiana University School of NursingIndiana 600USA Department of Chinese Medicine Kaohsiung Chang Gung Memorial HospitalKaohsiung 80830Taiwan China

OBJECTIVE:To investigate the effect of acupressure on postpartum low back pain(LBP),salivary cortisol,physical limitations,and postpartum ***:Participants were 70 postpartum women who were randomly assigned to either an intervention(n=35)or a control(n=35)*** intervention group received 10 acupressure sessions(1 session per day,5 d per week).The control group received 10 sham acupressure *** were assessed using a visual analogue scale(LBP intensity),salivary cortisol values(LBP biomarker),and Chinese versions of the Roland-Morris Disability Questionnaire(daily activity limitations),Oswes-try Disability Index(physical activity limitations),and the Edinburgh Postnatal Depression Scale(postpartum depression).RESULTS:Participants in the intervention group had significantly lower levels of LBP intensity,daily activity limitations,physical activity limitations,and postpartum depression than those in the control *** was no significant between-group difference in salivary ***:Acupressure may reduce postpartum LBP intensity and limitations in daily and physical activity,and alleviate postpartum depressive *** should be offered in postpartum care settings as an alternative treatment for postpartum women with LBP.

关键词： Acupressure Low back pain Postpartum period Depression Randomized controlled trial Pilot projects

Effect of hand-ear acupuncture on chronic low-back pain: a randomized controlled trial

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Journal of Traditional Chinese Medicine 2019年第4期39卷 587-594页

作者： Luo Yong Yang Min Liu Tao Zhong Xiaolong Tang Wen Guo Mingyang Hu Yonghe Graduate College The People's Liberation Army Naval Medical UniversityShanghai 200433China Traditional Chinese Medicine Department The General Hospital of Western Theater CommandChengdu 610083China Traditional Chinese Medicine Department The General Hospital of Western Theater CommandChengdu 610083China The People's Liberation Army 32357 troops Chengdu 611630China

OBJECTIVE: To evaluate the effect of hand-ear acupuncture on chronic low-back pain(cLBP).METHODS: This was an open, randomized and controlled trial in The General Hospital of Western Theater Command, Sichuan Province. The trial was registered with ***, NCT02260284. All the 152 participates with cLBP were randomly assigned to hand-ear acupuncture(n = 54), standard acupuncture(n = 50), or usual care groups(n = 48).Eighteen treatments were provided over 7 ***-related dysfunction and symptom severity were assessed by the Roland-Morris Disability Questionnaire(RMDQ) and the Visual Analogue Scale(VAS), which were collected at baseline, 2 months and 6 months post to the ***: At 6 months, the RMDQ scores improved by 7.74 points of hand-ear acupuncture group. Significant improvement of VAS and RMDQ was observed in hand-ear acupuncture group(P < 0.001),but no significant changes of RMDQ were observed in both standard acupuncture group and usual care group. We also observed an overall efficacy rate of 88.89% in hand-ear acupuncture group, as evaluated by Diagnosis and Curative Effect Standard for Symptom pattern of Traditional Chinese Medicine, which was much higher than 45.84% in the usual care group(H = 16.000, P < 0.001).CONCLUSION: Both of the hand-ear acupuncture and standard acupuncture modes have beneficial and persistent effectiveness against cLBP compared with the usual care. Furthermore, hand-ear acupuncture is significantly more effective than the standardized acupuncture, especially in the long term.

关键词： Low back pain Acupuncture Visual analogue scale Questionnaire Randomized controlled trial

Slope reliability and back analysis of failure with geotechnical parameters estimated using Bayesian inference

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 628-643页

作者： Luis-Fernando Contreras Edwin T.Brown The University of Queensland St Lucia Campus

A Bayesian approach is proposed for the inference of the geotechnical parameters used in slope *** methodology involves the construction of posterior probability distributions that combine prior information on the parameter values with typical data from laboratory tests and site investigations used in *** posterior distributions are often complex,multidimensional functions whose analysis requires the use of Markov chain Monte Carlo(MCMC)*** procedures are used to draw representative samples of the parameters investigated,providing information on their best estimate values,variability and *** paper describes the methodology to define the posterior distributions of the input parameters for slope design and the use of these results for evaluation of the reliability of a slope with the first order reliability method(FORM).The reliability analysis corresponds to a forward stability analysis of the slope where the factor of safety(FS)is calculated with a surrogate model from the more likely values of the input *** Bayesian model is also used to update the estimation of the input parameters based on the back analysis of slope *** this case,the condition FS?1 is treated as a data point that is compared with the model prediction of *** analysis requires a sufficient number of observations of failure to outbalance the effect of the initial input *** parameters are updated according to their uncertainty,which is determined by the amount of data supporting *** methodology is illustrated with an example of a rock slope characterised with a Hoek-Brown rock mass *** example is used to highlight the advantages of using Bayesian methods for the slope reliability analysis and to show the effects of data support on the results of the updating process from back analysis of failure.

关键词： Bayesian analysis Hoek-Brown criterion Slope reliability back analysis of failure

Cetacean morbillivirus: A Land-to-Sea Journey and back?

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Virologica Sinica 2019年第3期34卷 240-242页

作者： Giovanni Di Guardo Sandro Mazzariol Faculty of Veterinary Medicine University of TeramoLocalita Piano d'Accio64100 TeramoItaly Department of Comparative Biomedicine and Food Science University of PaduaAgripolis35020 LegnaroPadovaItaly

Cetacean morbillivirus(CeMV),the most relevant pathogen impacting the health and conservation of several already threatened cetacean populations worldwide(Van Bressem et al.2014),has shown in recent years an apparently increased tendency to cross"interspecies barriers"(Jo et al.2018a),thereby giving rise to disease and mortality outbreaks in free-ranging dolphins and whales(Mazzariol et al.2016,2017;Jo et al.2018b).

关键词： Cetacean morbillivirus A Land-to-Sea Journey and back

Wet-Cupping Is Effective on Persistent Nonspecific Low back Pain: A Randomized Clinical Trial

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Chinese Journal of Integrative Medicine 2019年第7期25卷 502-506页

作者： Mohsen Mardani-Kivi Reza Montazar Mohammad Azizkhani Keyvan Hashemi-Motlagh Department of Orthopedic Guilan University of Medical Sciences Rasht Iran General Practitioner Traditional Medicine Specialist Tehran Iran Orthopedic Research Center Rasht Iran

Objective: To compare the possible effects of wet-cupping therapy with conventional therapy on persiste nt non specific low back pain (PNSLBP). Methods: In this ran domized clinical trial, 180 participa nts with the mean age of 45 ±10 years old, who had been suffering from PNSLBP were randomly assigned to wet-cupping and conventional groups using random blook. The wet-cupping group was treated with two separate sessions (4 weeks in total) on the inter-scapular and sacrum area. In the conventional group, patients were conservatively treated using rest (6 weeks) and oral medicati ons (3 weeks). The primary and the sec on dary outcome were the qua ntity of disability using Oswestry Disability Index (ODI), and pain intensity using Visual Analogue Scale (VAS), respectively. Results: There was no significant difference in demographic characteristics (age, gender, and body mass index) between the two groups (P>0.05). Therapeutic effect of wet-cupping therapy was comparable to conventional treatment in the 1st month follow-up visits (P<0.05). The functional outcomes of wet-cupping at the 3rd and 6th month visits were significantly increased compared to the conventional group. Final ODI scores in the wet-cupping and conventional groups were 16.7 ±5.7 and 22.3 ±4.5, respectively (P<0.01). Conclusion: Wet-cupping may be a proper method to decrease PNSLBP without any conventional treatment. The therapeutic effects of wet-cupping can be longer lasting than conventional therapy.(Registration No. IRCT2013021672741).

关键词： low back pain chronic wet-cupping therapy traditi onal medici ne Chin ese medici ne alter native medicine conservative treatment randomized clinical trial

Altered small-world,functional brain networks in patients with lower back pain

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Science China(Life Sciences) 2018年第11期61卷 1420-1424页

作者： Jing Liu Feng zhang Xiufen Liu Zhizheng Zhuo Juan Wei Minyi Du Queenie Chan Xiaoying Wang Dongxin Wang Department of Radiology Peking University First HospitalBeijing 100034China Department of Anesthesiology Peking University First HospitalBeijing 100034China Philips Healthcare Beijing 100600China Philips Research China Shanghai 200040China Philips Healthcare Hong KongChina

In this study, we aimed to investigate the functional network changes that occur in patients with lower back pain(LBP). We also investigated the link between LBP and the small-world properties of functional networks within the brain. Functional MRI(fMRI) was performed on 20 individuals with LBP and 17 age and gender-matched normal controls during the resting state. The severity of the pain in the individuals with LBP ranged from 5 to 8 on a 0–10 scale, with 0 indicating no pain. Network-based statistics were performed to investigate the differences between the brain networks of individuals with LBP and those of normal controls. Several small-world parameters of brain networks were calculated, including the clustering coefficient, characteristic path length, local efficiency, and global efficiency. These criteria reflect the overall network efficiency. The brain networks in the individuals with LBP due to herniation of a lumbar disc demonstrated a significantly longer characteristic path length as well as a lower clustering coefficient, global efficiency, and local efficiency compared to those in control subjects. We found that LBP patients tended to have unstable and inefficient brain networks when compared with healthy controls. In addition, LBP individuals showed significantly decreased functional connectivity in the anterior cingulate cortex, middle cingulate cortex, post cingulate cortex, inferior frontal gyrus, middle temporal gyrus, occipital gyrus, postcentral gyrus, precentral gyrus, supplementary motor area, thalamus, fusiform, caudate, and cerebellum. We believe that these regions may be involved in the pathophysiology of lower back pain.

关键词： small-world network brain functional networks resting-state fMRI low back pain