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Finite Element Simulation of In-Stent Restenosis with Tissue Growth Model 认领
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作者 Jie Cheng Lucy T. Zhang 《生物医学工程(英文)》 2021年第2期33-47,共15页
In this study, a finite element simulation of in-stent restenosis (ISR) is conducted to simulate the deployment and expansion of a stent in an occluded artery with a contact model and a mechanics-based growth model. A... In this study, a finite element simulation of in-stent restenosis (ISR) is conducted to simulate the deployment and expansion of a stent in an occluded artery with a contact model and a mechanics-based growth model. A tissue growth model based on the multiplicative decomposition of deformation is applied to investigate the growth of the plaque and artery wall upon the stent’s implantation. Due to the high stresses at the contact points between the stent struts and the tissue, further tissue injury or restenosis is observed. The simulation results show that after the stent deployment, the von Mises stress is significantly larger in the plaque compared to the artery wall, especially in the region that is in contact with the stent. However, the growth of the plaque and artery tends to even out the stress concentration over time. The tissue growth is found to be more significant near the inner wall than the outer layer. A 0.77 mm restenosis is predicted, which agrees with published clinical observations. The features of the artery growth are carefully analyzed, and the underlying mechanism is discussed. This study is the first attempt to apply finite element analysis to artery restenosis, which establishes a framework for predicting ISR’s occurrence and severity. The results also provide insights into understanding the underlying mechanism of in-stent restenosis. 展开更多
关键词 STENTS In-Stent Restenosis Tissue Growth Finite Element Simulation Growth Model
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Functional recovery after peripheral nerve injury via sustained growth factor delivery from mineral-coated microparticles 认领
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作者 Daniel J.Hellenbrand Clayton L.Haldeman +9 位作者 Jae-Sung Lee Angela G.Gableman Elena K.Dai Stephen D.Ortmann Jerrod CGotchy Kierra K.Miller Adrianna M.Doucas Nicole C.Nowak William L.Murphy Amgad S.Hanna 《中国神经再生研究:英文版》 SCIE CAS 2021年第5期871-877,共7页
The gold standard for treating peripheral nerve injuries that have large nerve gaps where the nerves cannot be directly sutured back together because it creates tension on the nerve,is to incorporate an autologous ner... The gold standard for treating peripheral nerve injuries that have large nerve gaps where the nerves cannot be directly sutured back together because it creates tension on the nerve,is to incorporate an autologous nerve graft.However,even with the incorporation of a nerve graft,generally patients only regain a small portion of function in limbs affected by the injury.Although,there has been some promising results using growth factors to induce more axon growth through the nerve graft,many of these previous therapies are limited in their ability to release growth factors in a sustained manner and tailor them to a desired time frame.The ideal drug delivery platform would deliver growth factors at therapeutic levels for enough time to grow axons the entire length of the nerve graft.We hypothesized that mineral coated microparticles(MCMs)would bind,stabilize and release biologically active glial cell-derived neurotrophic factor(GDNF)and nerve growth factor(NGF)in a sustained manner.Therefore,the objective of this study was to test the ability of MCMs releasing growth factors at the distal end of a 10 mm sciatic nerve graft,to induce axon growth through the nerve graft and restore hind limb function.After sciatic nerve grafting in Lewis rats,the hind limb function was tested weekly by measuring the angle of the ankle at toe lift-off while walking down a track.Twelve weeks after grafting,the grafts were harvested and myelinated axons were analyzed proximal to the graft,in the center of the graft,and distal to the graft.Under physiological conditions in vitro,the MCMs delivered a burst release of NGF and GDNF for 3 days followed by a sustained release for at least 22 days.In vivo,MCMs releasing NGF and GDNF at the distal end of sciatic nerve grafts resulted in significantly more myelinated axons extending distal to the graft when compared to rats that received nerve grafts without growth factor treatment.The rats with nerve grafts incorporated with MCMs releasing NGF and GDNF also showed significant improvement in hind 展开更多
关键词 AUTOGRAFTS axon growth drug delivery glial cell-derived neurotrophic factor growth factors mineral coatings nerve grafting nerve growth factor
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Angiogenesis and nerve regeneration induced by local administration of plasmid pBud-coVEGF165-coFGF2 into the intact rat sciatic nerve 认领
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作者 Ruslan Masgutov Alina Zeinalova +11 位作者 Alexey Bogov Galina Masgutova Ilnur Salafutdinov Ekaterina Garanina Valeriia Syromiatnikova Kamilla Idrisova Adelya Mullakhmetova Dina Andreeva Liliya Mukhametova Adilet Kadyrov Igor Pankov Albert Rizvanov 《中国神经再生研究:英文版》 SCIE CAS 2021年第9期1882-1889,共8页
Vascular endothelial growth factor(VEGF) and fibroblast growth factor 2(FGF2) are well-known growth factors involved in the regeneration of various tissues and organs, including peripheral nerve system. In the present... Vascular endothelial growth factor(VEGF) and fibroblast growth factor 2(FGF2) are well-known growth factors involved in the regeneration of various tissues and organs, including peripheral nerve system. In the present study, we elucidated the local and systemic effects of plasmid construct рBud-coVEGF165-coFGF2 injected into the epineurium of intact rat sciatic nerve. Results of histological examination of sciatic nerve and multiplex immunoassays of serum showed the absence of immunogenicity and biosafety of plasmid рBud-coVEGF165-coFGF2. Moreover, local administration of plasmid DNA construct resulted in significantly decreased levels of pro-inflammatory cytokines in the peripheral blood, including tumor necrosis factor α(TNFα) and interleukin-12, and significantly increased levels of cytokines and chemokines including Regulated upon Activation, Normal T Cell Expressed and Presumably Secrete(RANTES), epidermal growth factor, interleukin-2, and monocyte chemoattractant protein 1. These changes in the peripheral blood on day 7 after injection of plasmid construct рBud-coVEGF165-coFGF2 show that the plasmid construct has systemic effects and may modulate immune response. At the same time, reverse transcriptionpolymerase chain reaction revealed transient expression of coFGF2, coVEGF165, ratFGF2 and ratVEGFA with direct transport of transcripts from distal part to proximal part of the sciatic nerve. Immunohistochemical staining revealed prolonged presence of VEGFA in sciatic nerve till 14 days post-injection. These findings suggest that local administration of plasmid construct рBud-coVEGF165-coFGF2 at a concentration of 30 ng/μL results in the formation of pro-angiogenic stimuli and, and the plasmid construct, used as a drug for gene therapy, might potentially facilitate regeneration of the sciatic nerve. The study was approved by the Animal Ethics Committee of Kazan Federal University, procedures were approved by the Local Ethics Committee(approval No. 5) on May 27, 2014. 展开更多
关键词 CHEMOKINES CYTOKINES fibroblast growth factor gene therapy growth factors peripheral nerve system sciatic nerve regeneration vascular endothelial growth factor
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Determine the Optimal Density of Nile Tilapia (<i>Oreochromis niloticus</i>) Fingerlings Cultured in Floating Cages 认领
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作者 B. A. El Nouman O. A. Egbal +3 位作者 Y. A. Sana M. S. Anwar A. A. Eman F. A. Yosif 《自然资源(英文)》 2021年第1期1-9,共9页
The objective of the study was to determine the optimal density of fingerlings of the Nile tilapia (<em>Oreochromis niloticus</em>) culture in floating cages with respect to growth performance and to know ... The objective of the study was to determine the optimal density of fingerlings of the Nile tilapia (<em>Oreochromis niloticus</em>) culture in floating cages with respect to growth performance and to know the effect of temperature on growth during the winter period. Tilapia fingerlings (mean weight 8.5 ± 0.36 g) were stocked at densities of 120, 180 and 360 fish/m<sup>3</sup> for 10 weeks. During culture, fish were fed a diet contains 35% protein made of peanut seed, cottonseed, wheat bran, and Sorghum. The results showed that the increase in fish density reduced the final weight of the fish. The percentage of the fish weight increased and reached 111% ± 1.45% in the lowest fish density (120 fish/m<sup>3</sup>), 79% ± 1.87% in the medium density (240 fish/m<sup>3</sup>), and 63% ± 2.03% of high fish density (360 fish/m<sup>3</sup>), therefore the daily growth rate was better in the lowest density. The rate of food conversion ratio was also better in the lowest density with 2.17 ± 0.33, followed by the medium density with 2.79 ± 0.28 and then the highest density with 3.09 ± 0.21. However, the total production in the cage increased with increasing fish density, and the return to the cost of food was better with higher fish density. According to various performance evaluation criteria, it can be concluded that the medium density 240 fish/m<sup>3</sup> is the best for growing Nile tilapia fingerlings in floating cages. It was observed that the growth rates of the three treatments were low due to the decrease in water temperature in most of the study period, which may indicate the useless of culture in cages in the winter season. 展开更多
关键词 Cage Culture Stocking Density Nile Tilapia Fingerlings Growth Performance SUDAN
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成长、成人、成才:新时代高校思想政治教育优化策略 认领
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作者 刘艳 《教育理论与实践》 北大核心 2021年第3期23-26,共4页
思政课是落实立德树人根本任务的关键课程。从思想政治教育实践来看,成长、成人、成才能引导学生内化主流价值观,在实现培养社会主义的建设者和接班人目标方面具有重要意义。“三成”理念是新时代高校思政工作铸魂育人的本质要求。要对... 思政课是落实立德树人根本任务的关键课程。从思想政治教育实践来看,成长、成人、成才能引导学生内化主流价值观,在实现培养社会主义的建设者和接班人目标方面具有重要意义。“三成”理念是新时代高校思政工作铸魂育人的本质要求。要对标“三成”目标,找准现阶段思想政治教育的角色定位。在此基础上,用好“三成”理念加快思想政治教育的优化,要树立系统性育人理念,明确立德树人的本质要求;要构建一体化育人平台,强化思想政治教育的载体支撑;要探索全方位育人模式,打造思想政治教育的科学体系;要构建专业化育人团队,形成以人为本的教育生态。 展开更多
关键词 高校 思想政治教育 成长 成人 成才 健康成长 立德成人 立志成才 育人平台 育人模式 育人团队
Fruit Mass of <i>Carica papaya</i>L. from Cultivars Aliança and THB from the Width and Length of the Fruit 认领
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作者 Karina Tiemi Hassuda dos Santos Vinicius de Souza Oliveira +3 位作者 Gleyce Pereira Santos Jéssica Sayuri Hassuda Santos Omar Schmildt Edilson Romais Schmildt 《农业科学(英文)》 2021年第1期9-17,共9页
Papaya (<em>Carica papaya</em> L.) is a typical plant with a tropical climate, but also grown in subtropical regions. Using mathematical models well-adjusted allows with good precision to estimate characte... Papaya (<em>Carica papaya</em> L.) is a typical plant with a tropical climate, but also grown in subtropical regions. Using mathematical models well-adjusted allows with good precision to estimate characteristics of interest. The objective was to adjust an equation tha<em></em>t estimates the fruit mass for each cultivar of papaya, Alian<span style="white-space:nowrap;">&#231;</span>a and THB, using only one measure, length or width. The experiment was conducted in the municipality of Linhares in the state of Espírito Santo, Brazil. Seedlings were planted on the same day, spaced 3.6 × 1.5 m and in rows side by side. Initially, the equations were modeled, they were linearized and then the covariance analysis was performed in order to verify the possibility of an equation that would serve both cultivars. As the covariance was significant, it was necessary to develop equations for each cultivar. To obtain the growth equations, 350 fruits of cultivar Alian<span style="white-space:nowrap;">&#231;</span>a and 550 of THB were used. The validation was performed with 50 fruits of each. The characteristics evaluated were the largest width (W in mm), the longest fruit length (L, in mm) and the observed mass (OM in g). The equations that best fit were those of the power model that use width (W) as an independent variable. 展开更多
关键词 Non-Destructive Method Regression Validation Mathematical Equations Growth Modeling
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Comparative Growth Performance, Carcass Characteristics and Meat Quality of Local Horro and Exotic Cockerels of Tropical Origin Fed Growers Diet 认领
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作者 Abrar Biazen Urge Mengistu +3 位作者 Ameha Negassi Aseffa Getenet Abegaz Solomon Dessie Tadelle 《动物科学期刊(英文)》 2021年第1期62-83,共22页
Growth performance, carcass characteristics and meat quality of male chickens were evaluated using eight-week-old 360 cockerels from three exotic (Koekoek, Kuroiler and Sasso-R) and one Ethiopian indigenous (Horro) ge... Growth performance, carcass characteristics and meat quality of male chickens were evaluated using eight-week-old 360 cockerels from three exotic (Koekoek, Kuroiler and Sasso-R) and one Ethiopian indigenous (Horro) genotypes. Cockerels in each breed (90) were randomly allocated into three replications of 30 birds each and housed in deep litter pens for the experiment that lasted for 8 to</span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">16 weeks. The experiment was arranged in a Completely Randomized Design. Seven birds per breed were slaughtered at the end to determine carcass yield, chemical composition and quality attributes of meat. </span><span style="font-family:Verdana;">The Kuroiler breed has higher body weight</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> body weight change (</span><span style="font-family:Verdana;">1621.8 </span><span style="font-family:Verdana;">g)</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> average daily gain (</span><span style="font-family:Verdana;">28.9 g/day),</span><span style="font-family:Verdana;"> daily feed consumption (</span><span style="font-family:Verdana;">127.4 g/day) and better feed conversion ratio (4.40) than other breed</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;">. The Kuroiler breed has heavier </span><span style="font-family:Verdana;">slaughter weight (</span><span style="font-family:Verdana;">2716.3 </span><span style="font-family:Verdana;">g)</span><span style="font-family:Verdana;">,</span><span> </span><span style="font-family:Verdana;">dressed carcass weight (2201.0 g), eviscerated carcass weight (1905.1 g), breast weight (537.7 g), thigh weight (303.1 g) and drumstick weight (274.8 g) than other breeds. Total edible offal was higher </span><span style="font-family:Verdana;">for </span><span style="font-family:Verdana;">Kuroiler (324.2 g) and 展开更多
关键词 BREED Carcass Characteristics CHICKEN COCKEREL Growth Meat Quality
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Effect of Food Waste Compost (FWC) and its Non-Aerated Fermented Extract (NFCE) on Seeds Germination and Plant Growth 认领
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作者 Raja Jarboui Bilel Dhouib Emna Ammar 《土壤科学期刊(英文)》 2021年第2期122-138,共17页
The aim of this study was to investigate the effect of the food wastes compost (FWC) and its non-aerated fermented extract (NFCE) on seed germination and growth of tomato (<i>Solanum</i> <i>lycopersi... The aim of this study was to investigate the effect of the food wastes compost (FWC) and its non-aerated fermented extract (NFCE) on seed germination and growth of tomato (<i>Solanum</i> <i>lycopersicum</i> L.), watercress (<i>Nasturtium</i> <i>officinale</i>), chili pepper (<i>Capsicum</i> <i>annuum</i>), peas (<i>Pisum</i> <i>sativum</i> L.), chickpea (<i>Cicer</i> <i>arietinum</i>) and beans (<i>Vicia</i> <i>faba</i>) under greenhouse conditions. The FWC and NFCE were physico-chemically and microbiologically characterized. The NFCE effect was evaluated on tomato, watercress, and chili pepper seeds germination and seedling growth. However, for leguminous, pea, chickpea and bean seedlings, the FWC amended soils and irrigated with NFCE were tested for plants growth. The results of FWC analyses revealed that FWC has neutral pH, low EC and C/N ratio, with fertilizing elements (N, P, K and Mg) and lack of phytotoxic effect. The NFCE was characterized by low EC and relatively high carbon content (COD = 9700 mg/l), and intense microbial activity, notably mesophilic bacteria. Therefore, in fermented compost extract, mesophilic bacteria were increased by 225, yeasts by 25 and molds by 10 times compared to those of the investigated compost. In greenhouse, the diluted NFCE increased significantly (<i>p</i>< 0.05) germination and growth of the tested seedlings. Used alone, the FWC amended soil or the NFCE irrigated soil, improved the growth of tested seedlings. The use of soil amended with compost and irrigated by fermented compost extract decreased significantly the growth of the same experimented seedlings. Therefore, the FWC and its fermented extract were a suitable substrate for germination and growth of the studied seeds. 展开更多
关键词 Food Wastes COMPOST Fermented Compost Extract Seed Germination SEEDLING Growth
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基于D4S理论的可成长型婴儿床设计 认领
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作者 张浩 张雯 《湖南包装》 2021年第1期147-150,160,共5页
从婴童不同年龄阶段对家具的需求出发,探寻能够伴随婴童共同成长的家具,满足相应年龄阶段的使用需求。以D4S理论(Design For Sustainability)和可成长型理念为指导,通过用户市场调研与分析,对儿童的生理及心理特性、儿童产品的需求与功... 从婴童不同年龄阶段对家具的需求出发,探寻能够伴随婴童共同成长的家具,满足相应年龄阶段的使用需求。以D4S理论(Design For Sustainability)和可成长型理念为指导,通过用户市场调研与分析,对儿童的生理及心理特性、儿童产品的需求与功能进行分析,在此基础上总结可成长型儿童家具设计原则,做出合理的功能设计,包括可调节的结构、尺寸及功能。通过零件的组合、变化和转换实现最少资源的多功能化,以多功能的使用方式延长家具的使用寿命。运用可持续设计理念和可成长型设计的原则设计儿童家具,可有效延长婴儿床的使用生命周期,有利于满足不同阶段儿童使用需求的变化,丰富婴幼儿的使用体验感,培养儿童独立性帮助儿童健康成长,同时可提高儿童家具产品的利用率及同类产品的竞争力。 展开更多
关键词 D4S 可成长 儿童家具 婴儿床 模块化
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Growth and Simulation Study of Glycine Sodium Nitrate Non-Linear Single Crystal 认领
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作者 Wafa S. Abdelrahman Abdelrazig M. Abdelbagi +1 位作者 Abbaker A. Abdalla Mubarak E. Ahmed 《材料物理与化学进展(英文)》 2021年第1期20-30,共11页
The present study is designed to simulate and study the production of single crystals of semi-organic non-linear optical Glycine Sodium Nitrate (GSN) by using hyper6 software and experimentally by slow evaporation tec... The present study is designed to simulate and study the production of single crystals of semi-organic non-linear optical Glycine Sodium Nitrate (GSN) by using hyper6 software and experimentally by slow evaporation technique. This work has investigated the molecular properties of the crystals using the density functional theory to obtain the infrared spectrum of the crystal by simulation. The FTIR investigation of growing crystal has shown that the spectrum of the GSN crystal compared to simulation evaluation is similar;the only difference is in the range of 1.9% to 2.75% of wavelength peak values. The ultraviolet experimental measurement of the GSN molecule reveals the possibility of non-linear properties due to the spectrum cutoff in the wavelength peak of 301 nm. There was a significantly positive correlation between simulation and experimental assessment. 展开更多
关键词 Glycine Sodium Nitrate Simulation Crystal Growth FTIR Spectrometer UV-Spectrophotometer
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Impact of Composts Maturity on Growth and Agronomic Parameters of Maize (<i>Zea mays</i>) 认领
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作者 Mawuli Tamakloe Edem Komi Koledzi +2 位作者 Etsè Aziable Maglwa Tcha-Thom Nitale M’Balikine Krou 《美国分析化学(英文)》 2021年第2期29-45,共17页
Several methods have been developed in the literature which allow the maturity of composts to be assessed before it is used in agriculture. The objective of this study is to assess the maturity of the composts produce... Several methods have been developed in the literature which allow the maturity of composts to be assessed before it is used in agriculture. The objective of this study is to assess the maturity of the composts produced at the platform of the NGO ENPRO in Lomé on the growth and agronomic parameters of maize (<i>Zea mays</i> L., var. IKENE). To do so, three types of compost (gargabe, fruit waste, animal litter) were made for at least 3 months. The chemical analysis, phytotoxicity and agronomic tests carried out made it possible to assess the maturity of these composts. Indeed, the evolution of the C/N ratio, of the electrical conductivity, the phytotoxicity tests and the growth parameters of the composts show that the composts N°1 and N°2 are mature at the end of the 3<sup>rd</sup> month of composting while the compost N°3 can only be considered mature at the end of the 5<sup>th</sup> month of composting. But, with a yield of 2.39 ± 0.28 t/ha and a mass of 1000 grains of 346 ± 4 g, the treatment at 5 t/ha of compost N°3, has the best agronomic parameters compared to other types of compost and treatment without organic amendment. These results also show that compost with a high electrical conductivity has an inhibitory effect on the growth of corn plants (<i>Zea mays</i> L., var. IKENE). Basic chemical analysis, phytotoxicity tests and height growth of maize (<i>Zea mays</i> L., var. IKENE) are relatively efficient methods for evaluating the maturity of composts. 展开更多
关键词 Compost Phytotoxicity Agronomic Parameters GROWTH Maize (Zea mays L. var. IKENE)
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Adsorption of Phosphate and Nitrate Using Modified Spent Coffee Ground and Its Application as an Alternative Nutrient Source for Plant Growth 认领
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作者 Aisyah Humayro Hiroyuki Harada Kanako Naito 《农业化学和环境(英文)》 2021年第1期80-90,共11页
Phosphate (PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup><span style="font-family:Verdana;">) and Nitrate (NO<sub>3</sub><sup style="margin-... Phosphate (PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup><span style="font-family:Verdana;">) and Nitrate (NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;">) are two main nutrients that cause wa</span><span style="font-family:Verdana;">ter eutrophication. In the other hand, the presence of PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> is </span><span style="font-family:Verdana;">needed for plant growth. The aims of this study </span><span style="font-family:Verdana;">are </span><span style="font-family:Verdana;">to recycl</span><span style="font-family:Verdana;">e</span><span style="font-family:Verdana;"> Spent Coffee Ground (SCG) modified with calcium hydroxide for adsorption PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;">. The optimum adsorption capacity for PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> is 36.74 mg/L and 20.21 mg/L, respectively. The Freundlich isotherm model was suitable for PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and NO<sub>3</sub><sup style="margin-left:-9px;">-</sup></span><span style="font-family:Verdana;"> adsorption. The kinetic model for adsorption was linear using Pseudo-second order. The application of modified SCG after enrich</span><span style="font-family:Verdana;">ment with PO<sub>4</sub><sup style="margin-left:-9px;">3-</sup></span><span style="font-family:Verdana; 展开更多
关键词 Spent Coffee Ground ADSORPTION Calsium Hydroxide Phosphate and Nitrate Plant Growth
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Void Growth and Interaction in a Structural Aluminum Alloy: Experiments and Theory 认领
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作者 Scott Gampert Abu Bakar Siddique Tariq A. Khraishi 《矿物质和材料特性和工程(英文)》 2021年第1期14-37,共24页
The problem of void growth and interaction is of importance to understanding the mechanics of failure in metals exhibiting ductility. In this work, the growth and interaction of voids in 6061-T6 aluminum were studied ... The problem of void growth and interaction is of importance to understanding the mechanics of failure in metals exhibiting ductility. In this work, the growth and interaction of voids in 6061-T6 aluminum were studied experimentally. Specifically, holes of varying numbers and relative placement were investigated for their normalized area growth with applied displacement. Flat dog-bone specimens were carefully drilled in their gauge area with no (zero) holes, one hole, and two holes (arranged vertically or horizontally) for experimentation after polishing. The growth of holes, captured by video recordings, exhibited exponential behavior and was influenced greatly by the number and arrangement of holes with the horizontal voids growing the fastest and the vertical ones growing the slowest. Also, the ensuring deformation of the sample was studied using load-displacement curves, pictography and videography, SEM imaging and Atomic Force Microscopy (AFM). The methods revealed that although the major part failure is due to large crack formation, it was preceded by intense dislocation slip activity and the formation of micro cavities. Also, the AFM quantified the three-dimensional nature of crystal or grain deformation and how it is greatly influenced by distance and location from the hole. Lastly, theoretical understanding of hole growth was offered. 展开更多
关键词 Voids HOLES Stress Concentration Void Growth Void Interaction
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Synthesis, Growth and Characterization of Nonlinear Optical Single Crystal of Serine Succinate 认领
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作者 S. Akilandeswari L. Jothi 《矿物质和材料特性和工程(英文)》 2021年第1期75-89,共15页
Nonlinear optical single crystal of Serine Succinate (SSA) was grown from a mixed solvent of water, ethanol and methanol. Since amino acid exhibits nonlinear optical property, it is of interest to dope them in serine.... Nonlinear optical single crystal of Serine Succinate (SSA) was grown from a mixed solvent of water, ethanol and methanol. Since amino acid exhibits nonlinear optical property, it is of interest to dope them in serine. The overwhelming success of molecular engineering in controlling nonlinear optical properties in last decade has prompted better initiative in crystal engineering. In the present study single crystals of serine doped with succinic acid in different ratios have been grown by slow evaporation solution growth method. Grown serine succinate crystals were subjected to various characterization techniques. The cell parameters of the grown crystals were characterized by X-ray diffraction analysis. FT-Raman spectral studies were carried out on the SAA grown material to confirm the synthesized compound and the functional groups of serine succinate single crystal were identified from FTIR analysis. The optical transparency and upper cut off value of UV transmission spectrum of SSA crystal were recorded. Fluorescence study was also carried out for the grown materials. The mechanical hardness was estimated by Vickers’s micro hardness tester. The second harmonic generation (SHG) of the grown crystal was confirmed by Kurtz powder technique. Thermal properties of serine succinate crystal were evaluated with thermogravimetric, differential thermal and differential scanning calorimetric analyses. The SEM studies were also reported. 展开更多
关键词 Crystal Growth Slow Evaporation Technique Thermo Gravimetric Analysis
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外源褪黑素对桃生长及果实品质的影响 认领
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作者 吴彩芳 李红艳 +9 位作者 刘琴 廖明安 刘磊 吕秀兰 梁东 王进 夏惠 林立金 陈栋 涂美艳 《果树学报》 CAS 北大核心 2021年第1期40-49,共10页
【目的】探讨外源褪黑素对桃生长和果实品质的影响。【方法】以早熟桃‘早蜜’为试材,于果实膨大期对其叶片喷施不同浓度的褪黑素,测定了桃果实成熟期的新梢生长量、生理状况和果实品质指标。【结果】50~150μmol·L^-1的褪黑素处... 【目的】探讨外源褪黑素对桃生长和果实品质的影响。【方法】以早熟桃‘早蜜’为试材,于果实膨大期对其叶片喷施不同浓度的褪黑素,测定了桃果实成熟期的新梢生长量、生理状况和果实品质指标。【结果】50~150μmol·L^-1的褪黑素处理能促进桃新梢的生长,增加其茎长和茎粗。150μmol·L^-1褪黑素提高了桃叶片超氧化物歧化酶活性,但其余处理较对照有所降低;50~100μmol·L^-1褪黑素提高了桃叶片过氧化氢酶活性,其余处理较对照有所降低。褪黑素提高了桃果实的苯丙氨酸解氨酶、抗坏血酸过氧化酶和脂氧合酶活性,降低了多酚氧化酶活性。100~150μmol·L^-1褪黑素增加了桃果实单果质量、果实纵横径,降低了果实硬度,提高了果实维生素C、可溶性固形物、蔗糖、果糖和山梨醇含量,降低了葡萄糖含量。【结论】褪黑素能够促进桃生长、改善桃果实品质。 展开更多
关键词 褪黑素 生长 果实品质
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成龄枣树高接换优新技术 认领
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作者 薛晓芳 赵爱玲 +3 位作者 王永康 任海燕 李登科 李毅 《果树资源学报》 2021年第1期56-58,共3页
高接换优是实现枣树良种化的有效途径,对枣园提质增效、促进农民增收具有重要意义。介绍了一种当年截干促发新枝、翌年在新萌发枝条上进行嫁接的成龄枣树高接换优新技术,并从接口愈合状况、嫁接后枝条生长状况、早期产量等方面对比了新... 高接换优是实现枣树良种化的有效途径,对枣园提质增效、促进农民增收具有重要意义。介绍了一种当年截干促发新枝、翌年在新萌发枝条上进行嫁接的成龄枣树高接换优新技术,并从接口愈合状况、嫁接后枝条生长状况、早期产量等方面对比了新技术与传统高接换优技术的差异。结果表明,新技术高接后接口愈合好、枝条生长量大、产量高,可大大提高枣园经济效益。 展开更多
关键词 枣树 高接换优 愈合 生长量 产量
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Association of an Increased Risk of Pre-eclampsia and Fetal Growth Restriction in Singleton and Twin Pregnancies with Female Fetuses 认领
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作者 Shilei Bi Lizi Zhang +10 位作者 Zhijian Wang Jingman Tang Sushan Xie Jingjin Gong Lin Lin Luwen Ren Lijun Huang Shanshan Zeng Jingsi Chen Lili Du Dunjin Chen 《母胎医学杂志(英文)》 2021年第1期18-23,共6页
Objective: To investigate whether the fetal gender affects the incidence of pre-eclampsia (PE) and fetal growth restriction (FGR) in singleton and twin pregnancies.Methods: This was a 10-year single-center, retrospect... Objective: To investigate whether the fetal gender affects the incidence of pre-eclampsia (PE) and fetal growth restriction (FGR) in singleton and twin pregnancies.Methods: This was a 10-year single-center, retrospective, cohort study from January 2009 to January 2019. A total of 57,129 singleton and 3699 twin pregnancies aged between 18-55 years old were recruited at the Third Affiliated Hospital of Guangzhou Medical University, China. We used multivariable logistic regression to analyze the effect of fetal gender on the incidence of PE and FGR.Results: In singleton pregnancies, the incidence rates of PE and FGR with a female fetus were higher than those with a male fetus (6.4% (1713/26,793)vs. 5.9% (1803/30,336),P < 0.05 and 3.5% (932/26,793)vs. 2.4% (745/30,336),P < 0.05, respectively). A female fetus was an independent risk factor for either PE or FGR (adjusted odds ratio: 1.169 or 1.563;95% confidence interval: 1.036-1.319 or 1.349-1.810, respectively). In twin pregnancies, the incidence of early-onset PE was greater in pregnancies with two females compared with two males or one male plus one female (4.6% (46/1003)vs. 4.1% (54/1305)vs. 2.4% (33/1391),P < 0.05). Female-female twins was an independent risk factor for PE (adjusted odds ratio: 1.367, 95% confidence interval: 1.011-1.849), especially early-onset PE.Conclusion: The female fetus was associated with PE in both singleton and twin pregnancies and was also a risk factor of FGR in singleton pregnancies. 展开更多
关键词 PRE-ECLAMPSIA Fetal growth restriction SEX SINGLETON Twin pregnancies X chromosome Risk factor Placenta derived disease
试论《贵妇的画像》中伊莎贝尔的成长 认领
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作者 张艳萍 《赤峰学院学报:汉文哲学社会科学版》 2021年第1期95-98,共4页
《贵妇的画像》是19世纪末美国著名小说家亨利·詹姆斯的杰作之一,同时也是其创作早期代表作,是美国现代小说的一个里程碑式的作品,具有较强的可读性。这部作品结构严谨、内涵丰富,以精巧的笔触对女性的心理进行了细致入微的刻画。... 《贵妇的画像》是19世纪末美国著名小说家亨利·詹姆斯的杰作之一,同时也是其创作早期代表作,是美国现代小说的一个里程碑式的作品,具有较强的可读性。这部作品结构严谨、内涵丰富,以精巧的笔触对女性的心理进行了细致入微的刻画。本文通过《贵妇的画像》这本小说,对主人伊莎贝尔·阿切尔的成长进行了深入探讨。 展开更多
关键词 贵妇的画像 主人公 伊莎贝尔 成长
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Complications of Monochorionic Diamniotic Twins: Stepwise Approach for Early Identification, Differential Diagnosis, and Clinical Management 认领
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作者 Taita Micheletti Elisenda Eixarch +2 位作者 Mar Bennasar Josep Maria Martinez Eduard Gratacos 《母胎医学杂志(英文)》 2021年第1期42-52,共11页
One in three monochorionic twins may develop complications during pregnancy. Monochorionic twins, especially monochorionic diamniotic (MCDA), present specific problems caused by the presence of interfetal placental an... One in three monochorionic twins may develop complications during pregnancy. Monochorionic twins, especially monochorionic diamniotic (MCDA), present specific problems caused by the presence of interfetal placental anastomoses. The first critical step in the management of MCDA twins is identification in the first trimester. Secondly, close follow-up every 2 weeks is mandatory to allow early diagnosis and timely treatment of twin-twin transfusion syndrome. Other potentially severe complications include selective fetal growth restriction, twin anemia polycythemia syndrome or single fetal death. Thirdly, a correct differential diagnosis is critical to establish the best therapy. This may represent a clinical challenge since MCDA twin complications often overlap. A simple diagnostic algorithm may be of great help to establish the right diagnosis and management option. In this review we summarize the main steps for the clinical follow-up, differential diagnosis, and targeted management of MCDA twins complications. 展开更多
关键词 Acute feto-fetal transfusion Discordant malformation Monochorionic diamniotic twin pregnancy Pregnancy TWIN Selective fetal growth restriction Single intrauterine fetal death Twin anemia-polycythemia sequence Twin-twin transfusion syndrome
不同糊精含量低氮饲料对鲤生长及生理生化指标的影响 认领
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作者 韩依笑 汤雨 +4 位作者 郭立 程镇燕 孙金辉 崔培 乔秀亭 《天津农学院学报》 CAS 2021年第1期34-39,44,共7页
本试验研究了不同糊精含量低氮饲料对鲤(13.12±0.55)g生长及部分生理生化指标的影响。3组试验饲料(分别记作D1、D2和D3)糊精添加量分别为0%、7.5%、15.0%。经56 d养殖试验后测定鲤的生长和部分生理生化指标。结果表明,鱼体的增重... 本试验研究了不同糊精含量低氮饲料对鲤(13.12±0.55)g生长及部分生理生化指标的影响。3组试验饲料(分别记作D1、D2和D3)糊精添加量分别为0%、7.5%、15.0%。经56 d养殖试验后测定鲤的生长和部分生理生化指标。结果表明,鱼体的增重率、特定生长率和肥满度差异均不显著(P>0.05),D1的增重率和特定生长率均高于其他两组,均值为357.43%和2.53%,D3的肥满度达到3组最高,均值为4.00%。D2的血清中总胆固醇、甘油三酯和血清低密度脂蛋白胆固醇含量显著低于其他处理组(P<0.05),均值分别为16.70、1.73和1.27 mmol/L,血清高密度脂蛋白含量显著高于其他处理组(P<0.05),均值为2.33 mmol/L。D2的血清SOD活力显著高于D1(P<0.05),与D3无显著差异(P>0.05)。肝胰脏中SOD活力,D3为最高值,且与其他组没有显著差异(P>0.05)。D2血清CAT活力最高(P<0.05),血清及肝胰脏内MDA活力最低(P<0.05),AKP和LZM活力最高,且D2与D3的AKP活力差异显著(P<0.05)。由此可知,本试验饲料中糊精含量对鲤的生长没有显著效果,添加7.5%糊精的饲料对鲤的抗氧化能力和免疫力均有提高。 展开更多
关键词 糊精 生长 生理生化指标
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