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Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： nilo Cesar Consoli João Vítor de Azambuja Carvalho Alexia Cindy Wagner Hugo Carlos Scheuermann Filho Inácio Carvalho Pedro Pazzoto Cacciari João Paulo de Sousa Silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

Optimal transcorneal electrical stimulation parameters for preserving photoreceptors in a mouse model of retinitis pigmentosa

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neural Regeneration Research 2024年第11期19卷 2543-2552页

作者： Sam Enayati Karen Chang Anton Lennikov Menglu Yang Cherin Lee Ajay Ashok Farris Elzaridi Christina Yen Kasim Gunes Jia Xie Kin-Sang Cho tor Paaske Utheim Dong Feng Chen Schepens Eye Research Institute of Massachusetts Eye and Ear Department of OphthalmologyHarvard Medical SchoolBostonMAUSA Institute of clinical medicine Faculty of MedicineUniversity of OsloOsloNorway Department of Medical Biochemistry Oslo University HospitalUniversity of OsloOsloNorway Department of Ophthalmology Drammen HospitalVestre Viken Hospital TrustDrammenNorway Department of Histology and Embryology School of MedicineMarmara UniversityIstanbulTurkiye

Retinitis pigmentosa is a hereditary retinal disease that affects rod and cone photoreceptors,leading to progressive photoreceptor *** research supports the beneficial effect of electrical stimulation on photoreceptor *** study aims to identify the most effective electrical stimulation parameters and functional advantages of transcorneal electrical stimulation(tcES)in mice affected by inherited retinal ***,the study seeked to analyze the electric field that reaches the retina in both eyes in mice and post-mortem *** this study,we recorded waveforms and voltages directed to the retina during transcorneal electrical stimulation in C57BL/6J mice using an intraocular needle probe with rectangular,sine,and ramp *** investigate the functional effects of electrical stimulation on photoreceptors,we used human retinal explant cultures and rhodopsin knockout(Rho^(-/-))mice,demonstrating progressive photoreceptor degeneration with *** retinal explants isolated from the donors’eyes were then subjected to electrical stimulation and cultured for 48 hours to simulate the neurodegenerative environment in *** density was evaluated by rhodopsin *** vivo Rho^(-/-)mice were subjected to two 5-day series of daily transcorneal electrical stimulation using rectangular and ramp *** function and visual perception of mice were evaluated by electroretinography and optomotor response(OMR),*** was used to assess the morphological and biochemical changes of the photoreceptor and bipolar cells in mouse *** recordings indicated effective delivery of rectangular,sine,and ramp waveforms to the retina by transcorneal electrical stimulation,of which the ramp waveform required the lowest *** of the total conductive resistance of the post-mortem human compared to the mouse eyes indicated higher cornea-to-retina resistance in human *** tem

关键词： bipolar cells electrical stimulation neuroprotection photoreceptor degeneration retina retinal explants retinitis pigmentosa transcorneal electrical stimulation waveform

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Efficacy of Cyanoacrylate Tissue Adhesive Application in the Management of Corneal Perforations at Preah Ang Duong Hospital in Cambodia

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Open Journal of Ophthalmology 2024年第1期14卷 44-54页

作者： Guechlaing Chea Amarin Mar Saly Saint Remy tor Ponndara Ith Piseth Kong Ophthalmology Department Preah Ang Duong Hospital Phnom Penh Cambodia Faculty of Medicine University of Health Sciences Phnom Penh Cambodia

Purpose: The study was to evaluate the efficacy of cyanoacrylate tissue adhesive (CTA) application in corneal perforations. Method: This was a prospective study on 20 patients of corneal perforations who received cyanoacrylate tissue adhesive application as treatment between March 2021 and March 2022 at Preah Ang Duong Hospital. The primary outcome measure was success rate of CTA application, while the secondary outcome was to measure postoperative best-corrected visual acuity (BCVA) and ocular complications. Results: The mean age of patients was 44.15 ± 16.05 years old and 7 (35%) were female. Causes of perforation were microbial infection in 12 patients (60%), trauma in 5 patients (25%), and sterile melting in 3 patients (15%). The perforation of size smaller than 1.5 mm was in 8 patients (40%) while 12 patients (60%) had perforated size between 1.5 mm to 3 mm. The perforation was 60% (12 patients) central, 25% (5 patients) paracentral, and 15% (3 patients) peripherally. Out of 20 patients, 5 patients (25%) received CTA application more than 1 time. The mean glue retention was 57.60 ± 31.84 days. Success rate of glue application (defined as intact globe without surgical intervention regardless of number of CTA applications) was 85%. At the last visit, 7 patients (35%) had BCVA of 6/120 or better. Common complications were uveitis (45%), ocular hypertension (30%), cataract (25%) and neovascularization (20%). no serious complications were found. Conclusion: Cyanoacrylate tissue adhesive is an effective treatment option in sealing corneal perforations with no serious complications. .

关键词： Cyanoacrylate Tissue Adhesive Corneal Perforation Microbial Infection Sterile Melting

Epidemiologic, Diagnostic, and Therapeutic Features of Urinary Stone Disease in northern Benin from 2018 to 2023

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Open Journal of Urology 2024年第2期14卷 128-137页

作者： Gandaho Isidore Sossa Jean toré Sanni Rafiou Dènon Emmanuel Allodé Alexandre Avakoudjo Déjinnin Josué Georges Département de Chirurgie et Spécialités Chirurgicales Université de Parakou Parakou Bénin Faculté des Sciences de la Santé Université d’Abomey-Calavi Abomey-Calavi Bénin

Objective: To determine the epidemiologic, diagnostic, and therapeutic features of urinary in northern Benin from 2018 to 2023. Patients and Method: The study was an observational and descriptive one. We exhaustively and retrospectively collected data from the medical records of the patients that were managed from February 1, 2018 to February 1, 2023 at the Department of Surgery of “Centre Hospitalier Universitaire Départmental Borgou-Alibori or CHUD-BA”. Results: Among the 4522 patients managed, 75% or 1.7% had urinary stone disease. Their mean age was 41 years. The sex ratio was 2.75, the males being predominantly affected. Of the 75 cases of urinary stone disease, 30.7% (n = 23) were renal, 46.7% (n = 35) were ureteral, and 22.7% (n = 17) were vesical. The patients came from variable geographical areas, ethnic groups, and professional sectors. Their main complaints were pain (57.3%), hematuria (14.7%), dysuria (12%), and fever (5.3%). 15 (20%) patients, i.e., 7 renal stone and 8 ureteral stone patients, had an obstructive renal failure. The imaging tools available were ultrasonography, tomography and computed tomographic scan. 11 of the bladder stone cases (64.7%) were associated with a bladder outlet obstruction. Overall, 38.7% of the patients had either diabetes mellitus (6.7%), hypertension or high blood pressure (6.7%), benign prostate hyperplasia (8%), urinary schistosomiasis (6.7%), ureteral pelvic junction obstruction (2.7%), and prostate cancer (1.3%). Of the 19 patients whose dietary behavior was investigated 15 (79%), 11 (57.9%) et 11 (57.9%) demonstrated a diet which was respectively rich in milk, fromage and meat. 100% of bladder stones were removed through cystolithotomy. Renal stones were removed by pyelolithtomy (52.2%) and nephrolithotomy (21.7%). Ureteral stones were removed through ureterolithotomy (40%), expelled by means of alpha-blockers (40%) or managed with ureteral pigtail stent (20%). Conclusion: The hospital prevalence of urinary stone d

关键词： Urinary Stone Epidemiologic Diagnostic Therapeutic

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特网座面的绷紧度对办公椅舒适度的影响

林业工程学报 2024年

作者：齐蔚葛海林 OnDER tor 魏佳丽林珈好张继雷胡玲玲卡斯塔莫努大学森林工程系密西西比州立大学可持续生物质产品系浙江农林大学化学与材料工程学院圣奥科技股份有限公司

特网网布作为高端办公椅的接触面材料，因其良好的弹性和透气性，备受消费者亲徕。但是，有关特网材料的力学性能对办公椅舒适度影响的研究报道还较少，严重制约网布办公椅的研发升级。研究了特网的拉伸力学性能和座面绷紧度对不同体型... 详细信息

特网网布作为高端办公椅的接触面材料，因其良好的弹性和透气性，备受消费者亲徕。但是，有关特网材料的力学性能对办公椅舒适度影响的研究报道还较少，严重制约网布办公椅的研发升级。研究了特网的拉伸力学性能和座面绷紧度对不同体型人群的臀腿部体压分布和主观舒适度的影响。首先，测试分析了两种特网材料经、纬方向的拉伸力学性能；其次，通过改变特网尺寸量化了3种特网座面的绷紧度，并测试分析了6种特网座面与3种不同体型人群之间的体压分布；最后，针对6种不同特网和绷紧度的座面进行了舒适度主观评价。结果表明：特网种类和绷紧度对人体臀腿部的峰值压力、最大压力梯度和平均压力梯度有显著的交互作用影响。当座面为MW特网、绷紧度为T时，峰值压力、最大压力梯度和平均压力梯度最低；当座面为MJW特网、绷紧度为T时，峰值压力、最大压力梯度和平均压力梯度最高；综合主观评分和体压指标得出MW-T座椅的舒适度最高。本研究从主客观两方面分析了不同特网种类和绷紧度对座面舒适度的影响，为网布办公椅的网布座面设计和舒适度提升提供了科学依据。

关键词：特网拉伸性能座面绷紧度身体指数体压分布

Hormonal Regulation of Tissue-type Plasminogen Activator and Plasminogen Activator Inhibitor Type-1 Gene Expression in Cultured Mouse Sertoli Cells

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Science China Chemistry 1993年第3期36卷 319-328页

作者：刘以训杜群胡召元 ny tor Department of Endocrinology Institute of Zoology Academia Sinica Beijing 100080 PRC State Key Laboratory of Reproductive Biology Institute of Zoology Academia Sinica Beijing 100080 PRC Unit for Applied Cell and Molecular Biology Umea University S90187 Umea Sweden

We have demonstrated for the first time that (ⅰ) mouse Sertoli cells predominantly secrete tPA under the action of FSH and cAMP-generating agents, whereas Leydig cells mainly produce uPA; (ⅱ) Sertoli cells are also capable of secreting PAI-1, as well as FSH, growth factors and GnRH increase PAI-1 gene expression; (ⅲ) the increases in tPA and PAI-1 activities by different hormones in the conditioned media of Sertoli cells correspond to the increases in the levels of tPA and PAI-1 mRnA in the cultured cells, suggesting that the synthesis of the activator-inhibitor in mouse Sertoli cells is regulated at a transcriptional level and the tPA secreted by Sertoli cells may be involved in the spermatogenesis.

关键词： Sertoli cells tPA PAl-1 spermiation spermatogenesis.

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The Euclidean Distance Spectra of FDMA-CPM: Algorithms and Applications

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Chinese Journal of Electronics 2014年第4期23卷 821-826页

作者： LI Bing BAI Baoming tor Aulin ISn State Key Laboratory of Xidian University TCT Computer Science and Engineering Chalmers University of Technology

The performance of multiuser Continuous phase modulation(CPM) over the additive white Gaussian noise channel with coherent maximum likelihood detection is considered. Algorithms are developed to calculate the Euclidean distance spectra employing tree-search and Astar algorithm. The complexity of proposed algorithms are further reduced using trellis minimization. The distance spectrum is then used to evaluate the performance of multiuser CPM systems, which reveals that the performance of multiuser CPM can be significantly improved by using optimized parameters. Both equally-powered and non-equally powered systems are considered. numerical and simulated results confirm that the proposed algorithms can generate the distance spectra of all systems with lower complexity relative to previous methods and are particularly suited for multi user CPM systems.

关键词： Continuous phase modulation Minimum achievable Euclidean distance Achievable spectral efficiency Frequency division multiple acc

CVaR-based stochastic wind-thermal generation coordination for Turkish electricity market

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1307-1318页

作者： Aycan AYDOGDU Osman Bulent tor Ali nezih GUVEn Department of Electrical and Electronics Engineering Middle East Technical UniversityAnkara 06800Turkey The Bucharest University of Economic Studies BucharestRomania

Uncertainties in wind power forecasting,dayahead and imbalance prices for the next day possess a great deal of risks for the profit of generation companies participating in a day-ahead electricity *** companies are exposed to imbalance penalties in the balancing market for unordered mismatches between associated day-ahead power schedule and real-time *** of wind and thermal power plants alleviates the risks raised from wind *** paper proposes a novel optimal coordination strategy by balancing wind power forecasting deviations with thermal units in the Turkish day-ahead electricity *** main focus of this study is to provide an optimal trade-off between the expected profit and the risk under wind uncertainty through conditional value at risk(CVa R)*** problem is formulated as a two-stage mixed-integer stochastic programming problem,where scenario-based wind power approach is used to handle the stochasticity of the wind *** programming approach is utilized to attain the commitment status of thermal *** of the coordination with different day-ahead bidding strategies and trade-off between expected profit and CVa R are examined with comparative scenario studies.

关键词： Conditional value at risk(CVaR) Windthermal coordination Electricity market Wind power Thermal power

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Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： tor J. Johansen Richard Meadow Arctic Agriculture and Land Use Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence