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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 713-726页

作者： m.A.Najafgholipour S.Heidarian Radbakhsh E.Erfani Department of Civil and Environmental Engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

this paper presents an investigation of the seismic behavior of reinforced concrete(rc)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the OpenSees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： rc flat slab-column frames seismic behavior nonlinear analysis time history analysis

Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted t-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed m.AttA Reda N.BEHIRY mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt Nile Higher Institute for Engineering and technology Mansoura 11001Egypt

Recently,inverted t-beams have been used in reinforced concrete(rc)bridges to support transverse precast *** t-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-t beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted t-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened rc inverted t-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： rc bridges inverted t-beams strengthening hanger failure external prestressing

A hybrid machine-learning model for solar irradiance forecasting

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Clean Energy 2024年第1期8卷 100-110页

作者： Ameera m.Almarzooqi maher maalouf tarek H.m.El-Fouly Vasileios E.Katzourakis mohamed S.El moursi Constantinos V.Chrysikopoulos Department of Industrial and Systems Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE Electrical Engineering and Computer Science Department Khalifa University Abu DhabiUAE Department of Civil Infrastructure and Environmental Engineering Khalifa UniversityAbu DhabiPO Box 127788UAE School of Chemical and Environmental Engineering Technical University of CreteChaniaGreece

Nowcasting and forecasting solar irradiance are vital for the optimal prediction of grid-connected solar photovoltaic(PV)power *** plants face operational challenges and scheduling dispatch difficulties due to the fluctuating nature of their power *** the generation capacity within the electric grid increases,accurately predicting this output becomes increasingly essential,especially given the random and non-linear characteristics of solar irradiance under variable weather *** study presents a novel prediction method for solar irradiance,which is directly in correlation with PV power output,targeting both short-term and medium-term forecast *** proposed hybrid framework employs a fast trainable statistical learning technique based on the truncated-regularized kernel ridge regression *** proposed method excels in forecasting solar irradiance,especially during highly intermittent weather periods.A key strength of our model is the incorporation of multiple historical weather parameters as inputs to generate accurate predictions of future solar irradiance values in its scalable *** evaluated the performance of our model using data sets from both cloudy and sunny days in Seattle and medford,USA and compared it against three forecasting models:persistence,modified 24-hour persistence and least *** on three widely accepted statistical performance metrics(root mean squared error,mean absolute error and coefficient of determination),our hybrid model demonstrated superior predictive accuracy in varying weather conditions and forecast horizons.

关键词： solar power generation kernel ridge regression hybrid model forecasting

Correlation between Saccharomyces cerevisiae DNA in intestinal mucosal samples and anti-Saccharomyces cerevisiae antibodies in serum of patients with IBD

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World Journal of Gastroenterology 2006年第2期12卷 292-297页

作者： rc mallant-Hent m mooij BmE von Blomberg RK Linskens AA van Bodegraven PHm Savelkoul Department of Gastroenterology VU University Medical CenterAmsterdamThe Netherlands Department of medical microbiology and Infection Control VU University Medical CenterAmsterdamThe Netherlands Department of Immunology VU University Medical CenterAmsterdamThe Netherlands Department of Gastroenterology St Anna ZiekenhuisGeldropThe Netherlands

AIm： to investigate the correlation between ASCA and presence of mucosal S. cerevisiae DNA in a population of CD, ulcerative colitis （UC） patients and controls. mEtHODS： S. cerevisiae-specific primers and a fluorescent probe were designed for a 5＇ exonuclease real time PCR （taqmantm） assay, which is a homogenous system using a fluorescent-labelled probe for the detection of PCR product in real time. We analyzed the relation of the PCR results with the ASCA findings in a group of 76 inflammatory bowel disease （IBD） patients （31 CD, 45 UC） and 22 healthy controls （HC）. RESULtS： ASCA （IgA or IgG） were positive in 19 （61%） patients with CD, 12 （27%） with UC and none of the HC. PCR amplification was inhibited and excluded from the final results in 10 （22%） UC patients, 7 （22%） CD patients, and 6 （30%） HC. In only 15 of the mucosal samples, S. cerevisiae DNA was detected by real time PCR, including 7 （29%） in CD, 7 （19%） in UC, 1 （6%） in HC. In 4 CD and in 4 UC patients, ASCA and mucosal S. cerevisiae were positive. Hucosal S. cerevisiae was present in combination with negative ASCA IgA and IgG in 3 UC, and 3 CD patients. CONCLUSION： We conclude that since the presence of S. cerevisiae in colonic mucosal biopsy specimens is very rare, ASCA is unlikely to be explained by continuous exposure to S. cerevisiae in the mucosa. therefore, ASCA formation must occur earlier in life and levels remain relatively stable thereafter in immunological susceptible persons.

关键词： ASCA Saccharomyces cerevisiae mucosa IBD

Obstructive jaundice due to hepatobiliary cystadenoma or cystadenocarcinoma

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World Journal of Gastroenterology 2006年第35期12卷 5735-5738页

作者： Deha Erdogan Olivier rc Busch Erik AJ Rauws Otto m van Delden Dirk J Gouma thomas m van Gulik Department of Surgery Academic Medical Center University of Amsterdam The Netherlands Department of Hepatology Academic Medical Center University of Amsterdam The Netherlands Department of Surgery Radiology Academic Medical Center University of Amsterdam The Netherlands

Hepatobiliary cystadenomas (HBC) and cystadenocarci- nomas are rare cystic lesions. most patients with these lesions are asymptomatic, but presentation with ob- structive jaundice may occur. the first patient presented with intermittent colicky pain and recurrent obstructive jaundice. Imaging studies revealed a polypoid lesion in the left hepatic duct. the second patient had recurrent jaundice and cholangitis. Endoscopic retrograde cholan- giopancreatography (ErcP) showed a cystic lesion at the confluence of the hepatic duct. In the third patient with intermittent jaundice and cholangitis, cholangioscopy re- vealed a papillomatous structure protruding into the left bile duct system. In the fourth patient with obstructive jaundice, Ct-scan showed slight dilatation of the intrahe- patic bile ducts and dilatation of the common bile duct of 3 cm. ErcP showed filling of a cystic lesion. All patients underwent partial liver resection, revealing HBC in the specimen. In the fifth patient presenting with obstructive jaundice, ultrasound examination showed a hyperecho- genic cystic lesion centrally in the liver. the resection specimen revealed a hepatobiliary cystadenocarcinoma. HBC and cystadenocarcinoma may give rise to obstruc- tive jaundice. Evaluation with cross-sectional imaging techniques is useful. ErcP is a useful tool to differentiate extraductal from intraductal obstruction.

关键词： Liver Hepatobiliary cystadenoma Cystadenocarcinoma Obstructive jaundice Endoscopic retrograde cholangiopancreatography

Characterization of C-N thin Films Prepared by Ion Beam Sputtering

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Journal of materials Science & technology 1996年第4期12卷 312-314页

作者： tian, YJ Ren, XJ Yu, DL He, JL Chen, SZ Li, DC Yu, rc Zhang, m Wang, WK CHINESE ACAD SCI INST PHYSBEIJING 100080PEOPLES R CHINA

C-N thin films have been prepared by ion beam sputtering using pure N-2 as discharge gas. the ratio N/C of the films measured by Auger spectrum is 20% on an average. the results of X-ray diffraction and transmission electron microscopy show that beta-C3N4. phase exists in the films. X-ray photoelectron spectroscopy shows that nitrogen is mostly combined with carbon with triple (C=N) and double (C=N) bonds. the IR absorption shows an absorption bond near 2185 cm(-1) assigned to the C=N, no trace of C-C bond was observed.

关键词： thin films

Wound healing effect of methanolic leaf extract of Napoleona vogelii(Family:Lecythidaceae) in rats

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Asian Pacific Journal of tropical medicine 2014年第8期7卷 620-624页

作者： Adiele LC Adiele rc Enye JC Department of Pharmacology and toxicology Faculty of PharmacyMadonna UniversityEleleRiver StateNigeria Department of Pharmacy Federal Medical CenterOwerriImo StateNigeria Department of Anatomy and Cell Biology Division of Biomedical SciencesCollege of MedicineUniversity of SaskatchewanSaskatoonSKS7N 5E5Canada Cameco mS Neuroscience Research Center Saskatoon City HospitalSaskatoonSKS7K 0M7Canada

Objective:to investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric ***:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant *** the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),*** w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or *** wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under *** first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,***:the percentage yield of the extract was 49.80%w/w dry *** phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,***,steroids,proteins,and *** LD_(50) was beyond our experimental limit and was not *** concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,Pt on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:these data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine.

关键词： Wound healing Napoleona vogelii Petroleum jelly Neobacin Folkloric medicine

New methodological Approach to Investigation of Kinetics of REE Extraction in Nonstationary Conditions

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Journal of Rare Earths 2007年第4期25卷 385-391页

作者： Kopyrin A A Fomichev A A Afonin m A todd t A Saint-Petersburg Institute of technology Idaho National Laboratory

the influence of periodical oscillations of the temperature on extraction and stripping processes in the extraction systems was studied. two extraction systems were investigated：（1） 6 mol · L^-1 NaNO3-Nd（NO3）3-Pr（NO3）3-tBP kerosene and （2） [Nd（NO3）3 · 3tBP] -[ Pr（NO3）3 · 3tBP] -kerosene - 0.1 mol · L^-1 HNO3. mathematical modeling of the nonstationary membrane extraction has been enhanced by including the dependence of the extraction rate constants on temperature. the values of activation energy for direct and reverse extraction and stripping reactions of Pr and Nd were calculated from experimental temporal dependencies of metal concentration and temperature by solving the reverse kinetics problem using the proposed mathematical model, A series of experiments with periodical oscillations of the temperature on the extraction system for the separation of rare earth elements （REE） using bulk liquid membrane between two extractors were performed. the mathematical model adequately describes the experimental data. the optimization of the extraction process for separation of REE by liquid membrane, under the influence of periodical oscillation of the temperature, was made based on the extraction rate constants and activation energies. the optimal conditions of separation by liquid membrane were found： frequency and amplitude of thermal oscillations, liquid membrane flow rate, and optimal ratio between organic and aqueous phase in extractors.

关键词： kinetics extraction non-stationary rare earths

Results of percutaneous sclerotherapy and surgical treatment in patients with symptomatic simple liver cysts and polycystic liver disease

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World Journal of Gastroenterology 2007年第22期13卷 3095-3100页

作者： Deha Erdogan Otto m van Delden Erik AJ Rauws Olivier rc Busch Johan S Lameris Dirk J Gouma thomas m van Gulik Department of Surgery Academic Medical Center University of Amsterdam The Netherlands Department of Radiology Academic Medical Center University of Amsterdam The Netherlands Department of Gastroenterology Academic Medical Center University of Amsterdam The Netherlands

AIm: to evaluate the results of the treatment of simple liver cysts (solitary and multiple) and polycystic liver disease (PLD) using percutaneous sclerotherapy and/or surgical procedures in a single tertiary referral centre. mEtHODS: Retrospective analysis of 54 patients referred for evaluation and possible treatment of simple liver cysts (solitary and multiple) and PLD, from January 1997 to July 2006. RESULtS: Simple liver cysts were treated in 41 pts (76/) with a mean size of 12.6 cm. the most common reason for referral was abdominal pain or discomfort (85/). Percutaneous sclerotherapy was performed as initial treatment in 30 pts, showing cyst recurrence in 6 pts (20/). Surgical treatment was initially performed in 11 pts with cyst recurrence in 3 pts (27/). PLD was treated in 13 pts (24/) with a mean size of the dominant cyst of 13 cm. Percutaneous sclerotherapy for PLD was performed in 9 pts with recurrence in 7 pts (77.8/). Surgical treatment for PLD was undertaken in 4 pts (30.8/) with recurrence in all. Eventually, 2 pts with PLD in the presence of polycystic kidney disease underwent liver-and kidney transplantation because of deterioration of liver and kidney function. CONCLUSION: the majority of patients with simple liver cysts and PLD are referred for progressive abdominal pain. As initial treatment, percutaneous sclerotherapy is appropriate. Surgical deroofing is indicated in caseof cyst recurrence after percutaneous sclerotherapy. However, the results of percutaneous sclerotherapy and surgical treatment for PLD are disappointing. Partial liver resection is indicated when there is suspicion of a pre-malignant lesion.

关键词： Simple liver cyst Polycystic liver disease Percutaneous sclerotherapy Deroofing Complications

An Investigation on the Formation of Submerged Bar Under Surges in Sandy Coastal Region

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China Ocean Engineering 2012年第3期26卷 535-546页

作者： mustafa DEmIrcI m.Sami AKZ Civil Engineering Department Engineering FacultyMustafa Kemal UniversityskenderunHatay 31040Turkey Civil Engineering Department Engineering and Architecture Facultyukurova UniversityAdana 01100Turkey

Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accretion due to onoff shore sediment transportation. In the present study, the experiments on cross-shore sediment transport are carried out in a laboratory wave channel with initial beach slopes of 1/8, 1/10 and 1/15. By using the regular waves with different deep-water wave steepnesses generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials with medium diameters of d50=0.25, 0.32, 0.45, 0.62 and 0.80 mm. the offshore bar geometric characteristics are the horizontal distances from the shoreline to the bar beginning （Xb）, crest （Xt）, and ending （Xs） points, the depth from the bar crest to the still water level （ht）, and the bar volume （Vbar）. the experimental results have indicated that when the deep-water steepness （Ha/L0） increased, the net movement to seaside increased. With the increasing wave steepness, the bars moved to widen herewith the vertical distances from still water level to the bar beginning （Xb）, crest （Xt） and ending （Xs） points and the horizontal distances from the coast line to the bar beginning, crest and ending points increased. It was also shown from experimental results that the horizontal distances from the bar beginning and ending points to the coast line increased with the decrease of the beach slope. the experimental results obtained from this study are compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.

关键词： cross-shore sediment transport beach profiles bar parameters experimental study