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Study of geometric parameters for the design of short intakes with fan modelling 被引量:3
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作者 Andrea MAGRINI Ernesto BENINI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第11期18-32,共15页
The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodolog... The flow over a short intake is characterised by a strong interaction with the fan, that can only be captured when the rotor blades are modelled in the numerical simulations. In this paper, we use a coupled methodology to derive indications about relevant geometric variables affecting the high-incidence operation of an ultra-high bypass ratio turbofan intake with a length-to-diameter ratio of 0.35. By reproducing the effect of the fan through a body force model, we carry out a parametric study of the influence of the contraction ratio and the scarf angle at take-off conditions for a grid of 28 different three-dimensional shapes. The analysis of the selected performance metrics distributions at three angles of attack of 16., 24., and 28. reveals that a contraction ratio higher than 1.20 is needed to avoid separation at high incidence. While for an attached inlet the best performance is found with a moderate scarf angle, in presence of a developed separation the distortion level reduces as the scarf decreases up to negative values. We discuss the correspondence between the distortion indexes and the flow field, highlighting the origin of the detachment for the different geometries, according to the operating condition, and analysing the fan operation in the most distorted case. Finally, we assess the influence of modelling the rotor in the simulations, showing that its suppression effect on the separation at a given incidence depends on the intake geometric features. 展开更多
关键词 Body force method Coupled methods fan/intake interaction Nacelle aerodynamics Short intake UHBPR
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Nutrient Intakes from Food of Lactating Women Do Not Meet Many Dietary Recommendations Important for Infant Development and Maternal Health 被引量:1
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作者 Nathan S. Pratt Holiday A. Durham Christina L. Sherry 《Food and Nutrition Sciences》 2014年第17期1644-1651,共8页
Literature describing dietary intakes of lactating mothers in the United States (US) is limited and none of the existing studies attempts to identify whether dietary shortcomings of lactating mothers are distinct from... Literature describing dietary intakes of lactating mothers in the United States (US) is limited and none of the existing studies attempts to identify whether dietary shortcomings of lactating mothers are distinct from those of women of childbearing age in the US. The first objective of this observational study was to comprehensively analyze the dietary intakes of lactating mothers in the US to determine whether nutrient intakes from food were sufficient to meet recommendations. The second objective was to compare these intakes to those of women of childbearing age in the US. Weekly 3-day food records were collected from subjects for six weeks in 2012-2013. Subject mean daily intakes of food groups, macronutrients, vitamins, minerals, carotenoids, and specific fats including omega-3 and omega-6 fatty acids were determined and compared to daily recommendations. Intakes were compared to US women using the 2009-2010 National Health and Nutrition Examination Survey. Fruit, vegetable, and dairy intakes of mothers were ≤50% of recommendations, resulting in 12 of 26 analyzed vitamins or minerals including potassium, iodine, chromium, choline, and vitamins A, D, and E having mean daily intakes below the Estimated Average Requirement. Vitamin D intake of subjects was 18% lower than US women, while most other nutrients showed intakes within 10% of each other between populations. Lactating women are not meeting the increased dietary needs associated with breastfeeding, supporting education initiatives and interventions specifically tailored to breastfeeding populations to increase intakes of vitamin D, vitamin E, iodine, biotin, carotenoids, and polyunsaturated fatty acids from food. 展开更多
关键词 BREASTFEEDING DIETARY intake NUTRITION Lactating
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Maternal Body Composition and Its Relationship to Infant Breast Milk Intake in Rural Pakistan 被引量:1
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作者 Nafeesa Nazlee Rakhshanda Bilal +1 位作者 Zahid Latif Les Bluck 《Food and Nutrition Sciences》 2011年第9期932-937,共6页
Some women in rural Pakistan are chronically undernourished, and consequently underweight. Concerns have been expressed that the degree of undernourishment might be sufficiently severe to affect lactation performance.... Some women in rural Pakistan are chronically undernourished, and consequently underweight. Concerns have been expressed that the degree of undernourishment might be sufficiently severe to affect lactation performance. We have obtained data on maternal body composition and infant breast milk intake using stable isotope methods in a group of thirty three mother and infant pairs at approximately six months of age. The maternal body mass index ranged from 16.6 to 29.1 kg·m-2. In this population we found that exclusive breast-feeding tended to be associated with lower maternal body fat, and that there was no evidence for compromised lactational performance due to malnourishment. Finally we note that when our data is combined with that from other studies there may be a generalised negative correlation between breast milk intake and maternal body fat. 展开更多
关键词 Stable ISOTOPES BREAST MILK intake MATERNAL Body Composition
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Evaluation of the Dietary Reference Intakes for Japanese (2010 Edition): Recommended Protein, Pantothenic acid, Vitamin D, and Iron Intakes for Breast-Fed Infants Aged 6 - 11 Months 被引量:1
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作者 Setsuko Tsutie Nobutaka Kurihara +3 位作者 Aki Sasaki Arisa Takagi Harumiti Seguti Tetsuya Inatome 《Food and Nutrition Sciences》 2011年第4期272-280,共9页
Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for ... Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula. 展开更多
关键词 Dietary Reference intakeS Breast-Fed INfanTS (6 - 11-Month-Old) Pantothenic Acid PROTEIN Vitamin D Iron
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Comparison of dietary intakes of Canadian Armed Forces personnel consuming field rations in acute hot, cold, and temperate conditions with standardized infantry 被引量:1
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作者 Mavra Ahmed Iva Mandic +3 位作者 Wendy Lou Len Goodman Ira Jacobs Mary R.L’Abbé 《Military Medical Research》 SCIE CAS CSCD 2020年第1期77-92,共16页
Background:Dietary Reference Intakes are used to guide the energy intake of the Canadian Armed Forces(CAF)field rations provided to military personnel deployed for training or operations.However,the high energy expend... Background:Dietary Reference Intakes are used to guide the energy intake of the Canadian Armed Forces(CAF)field rations provided to military personnel deployed for training or operations.However,the high energy expenditures likely to occur under harsh environmental/metabolically challenging deployment conditions may not be adequately considered.This study examined the Ad libitum energy and nutrient intakes of CAF personnel(n=18)consuming field rations in a resting thermoneutral environment and during a day of standardized strenuous infantry activities at varying environmental temperatures.Methods:Dietary intake was assessed using a measured food intake/food waste method during the experimental treatment and for 6 h after treatment.Four treatments were administered in a randomized counterbalanced design:exercise(as standardized infantry activities)in the heat(30℃),exercise in the cold(–10℃),exercise in temperate thermoneutral(21℃)air temperatures and a resting(sedentary)trial(21℃).Results:The average Ad libitum consumption of field rations was 70%of the provided total energy(2776±99 kcal/8 h)during all treatments.Even with an acute challenge of increased energy expenditure and temperature stress in the simulated field conditions,participants’energy intakes(1985±747 kcal/8 h)under hot,cold and temperate treatments did not differ from energy intake during the sedentary condition(1920±640 kcal/8 h).Participants’energy intakes(1009±527 kcal/6 h)did not increase during the 6 h posttreatment period when the stresses of the strenuous physical activities and the harsh environmental temperatures had subsided.Conclusions:These results should be considered when planning the provision of field rations for CAF personnel expected to be engaged in strenuous physical activities with prolonged exposure to temperature extremes. 展开更多
关键词 Dietary assessment Nutrient intakes Military personnel Physical activity Temperature extremes Field rations
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SPOCK2,a novel potential target for cereal intake in knee osteoarthritis
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作者 Erliang Li Jin Sun +2 位作者 Haishi Zheng Jiachen Wang Peng Xu 《Food Science and Human Wellness》 2025年第9期3519-3528,共10页
Lifestyle is related to many chronic diseases,such as knee osteoarthritis(KOA).Food intake is important because it can be controlled.However,the causal relationship of food intake and KOA still remain unclear.To ident... Lifestyle is related to many chronic diseases,such as knee osteoarthritis(KOA).Food intake is important because it can be controlled.However,the causal relationship of food intake and KOA still remain unclear.To identify the relationship between food intake and KOA and to screen relevant targets.First,we performed two-sample Mendelian randomization(MR)analysis.A total of 16 kinds of food intake datasets were included,the inverse variance-weighted analysis showed that the KOA was negatively correlated with cereal intake(odds ratio(OR)0.48;95%CI 0.35-0.68;P=1.98×10−5).Second,potential drug targets of KOA in plasma were explored,secreted protein acidic and rich in cysteine(SPARC,or osteonectin),SPARC,Cwcv,and Kazal-like domains proteoglycan 2(SPOCK2)as the causal protein for plasma with KOA,and increased SPOCK2(OR 0.84;95%CI 0.77-0.92;P=5.52×10−5),decreased the risk of KOA.Integrated transcriptomic analysis(P=0.0285)and in vivo(P=0.0395)showed consistent results.Finally,by metabolomics analysis and molecular docking,seven co-expressed small molecules were detected in cereal and were bound to SPOCK2.Our findings indicate the cereal intake was negatively correlated with KOA,and support the SPOCK2 as a novel potential target for cereal intake in KOA.Our study will provide a clinical dietary guidance for KOA patients and a theoretical basis for the development of novel,side-effect-free drugs for KOA. 展开更多
关键词 Knee osteoarthritis Mendelian randomization Food intake Cereal intake
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Re-Exploration for Dietary Iodine Intake in Chinese Adults using the Obligatory Iodine Loss Hypothesis
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作者 Xiaobing Liu Jun Wang +10 位作者 Yajie Li Hongxing Tan Deqian Mao Yanyan Liu Weidong Li Wei Yu Junan Yan Jianhua Piao Chongzheng Guo Xiaoli Liu Xiaoguang Yang 《Biomedical and Environmental Sciences》 2025年第8期952-960,共9页
Objective This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis.Methods Data from 171 Chinese adults(19–21 ... Objective This study aimed to reexplore minimum iodine excretion and to build a dietary iodine recommendation for Chinese adults using the obligatory iodine loss hypothesis.Methods Data from 171 Chinese adults(19–21 years old)were collected and analyzed based on three balance studies in Shenzhen,Yinchuan,and Changzhi.The single exponential equation was accordingly used to simulate the trajectory of 24 h urinary iodine excretion as the low iodine experimental diets offered(iodine intake:11-26μg/day)and to further deduce the dietary reference intakes(DRIs)for iodine,including estimated average requirement(EAR)and recommended nutrient intake(RNI).Results The minimum iodine excretion was estimated as 57,58,and 51μg/day in three balance studies,respectively.Moreover,it was further suggested as 57,58,and 51μg/day for iodine EAR,and 80,81,and 71μg/day for iodine RNI or expressed as 1.42,1.41,and 1.20μg/(day·kg)of body weight.Conclusion The iodine DRIs for Chinese adults were established based on the obligatory iodine loss hypothesis,which provides scientific support for the amendment of nutrient requirements. 展开更多
关键词 Iodine requirement Obligatory iodine loss Dietary reference intakes(DRIs) Estimated average requirement(EAR) Recommended nutrient intake(RNI)
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Optimal Design of Intake System for Racing Engine
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作者 Yang Sun Runze Yang 《Fluid Dynamics & Materials Processing》 2025年第7期1737-1751,共15页
The intake system of a racing engine plays a crucial role in determining its performance,particularly in terms of volumetric efficiency,power output,and throttle response.According to Formula Society of Automotive Eng... The intake system of a racing engine plays a crucial role in determining its performance,particularly in terms of volumetric efficiency,power output,and throttle response.According to Formula Society of Automotive Engineers(FSAE)regulations,the engine intake systemmust incorporate a 20mmdiameter flow-limiting valve within the intake manifold.This restriction significantly reduces the airflow into the engine,leading to a substantial drop in power output.To mitigate this limitation,the intake system requires a redesign.In this study,theoretical calculations and one-dimensional thermodynamic simulations are employed to determine the optimal parameters for the intake system.A numerical simulation of the intake system’s flow field is then conducted to refine its structure and layout.Finally,experiments are performed on an engine equipped with the optimized intake system,and its feasibility is evaluated based on experimental results.Thefindings indicate that the maximumengine torque increases from56.36 to 59.91 N⋅m,while the maximum power output rises from 59.16 to 63.94 kW.To further enhance performance and adaptability across different competitions,a variable-length intakemanifold control system is also designed,improving both power delivery and overall operational stability of the racing car. 展开更多
关键词 Internal combustion engine guide vane cascade variable intake manifold CFD
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Diagnostic dilemma of avoidant/restrictive food intake disorder after bariatric surgery:A case report and review of literature
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作者 Kamila Cass Adam Leggett Dennis Glen Gibson 《World Journal of Clinical Cases》 2025年第24期59-65,共7页
BACKGROUND Bariatric surgery is an effective treatment for severe obesity but is associated with an increased risk for development of eating disorders.Indeed,numerous maladaptive eating behaviors and eating disorders ... BACKGROUND Bariatric surgery is an effective treatment for severe obesity but is associated with an increased risk for development of eating disorders.Indeed,numerous maladaptive eating behaviors and eating disorders have been described following bariatric surgery.However,the differentiation of pathologic eating patterns from expected dietary changes following bariatric surgery can sometimes be difficult to discern.CASE SUMMARY A female in her early 40s presented for medical stabilization of severe protein calorie malnutrition after losing 52.3 kg over the last six months after Roux-en-Y gastric bypass,with subsequent development of cyclic nausea and vomiting.Fear of these aversive physical symptoms led to further restriction of nutritional intake and weight loss.The patient was diagnosed with avoidant/restrictive food intake disorder,which has not been previously reported after bariatric surgery.CONCLUSION Improvement in the diagnostic nomenclature for feeding and eating disorders is warranted for patients who have undergone bariatric surgery. 展开更多
关键词 MALNUTRITION Avoidant/restrictive food intake disorder Bariatric surgery Eating disorders Case report
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Spray Icing Simulation and Anti⁃icing Optimization for Ship Intake Grilles in Cold Environments
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作者 FENG Huiying PAN Tao +1 位作者 LOU Yanxia BU Xueqin 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第2期226-237,共12页
This study addresses the issue of spray icing on the air intake grilles of ship power systems in cold maritime environments.Through numerical simulation methods,the influence of environmental parameters on icing chara... This study addresses the issue of spray icing on the air intake grilles of ship power systems in cold maritime environments.Through numerical simulation methods,the influence of environmental parameters on icing characteristics is revealed,and an energy-efficient zoned electric heating anti-icing strategy is proposed.A threedimensional grille model is constructed to systematically analyze the effects of environmental temperature(from−20℃to−4℃),droplet diameter(from 50μm to 500μm),and liquid water content(from 0.5 g/m³to 8 g/m³)on icing rates and blockage of the flow channel.The results indicate that low temperature and high liquid water content significantly exacerbate icing.Under the condition of an environmental temperature of−20℃,droplet diameter of 500μm,and liquid water content of 8 g/m³,the flow channel blockage ratio reaches 30.95%within 10 min.Additionally,as droplet diameter increases,the droplet impingement and icing regions become more concentrated toward the leading edge of blades.To mitigate grille icing in cold environments,an electric heating film configuration is employed for thermal protection.Optimization of the heating strategy reveals that the zoned heating approach,compared to the initial uniform heating scheme,effectively homogenizes surface temperature distribution while reducing total power consumption by 37.47%.This study validates the engineering applicability of the zoned electric heating anti/de-icing strategy,providing theoretical and technical support for the design of anti-icing systems in ship power systems operating in cold maritime regions. 展开更多
关键词 ship intake grilles icing characteristics maritime environment flow channel blockage zoned electric heating strategy
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Causal relationship between multiple types of food intake and myopia:a Mendelian randomization study
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作者 Sha-Sha Zhang Jiao-Jiao Liang +4 位作者 Yun Feng Xia Hong Yi-Jia Zhao Ling Chen Ping Lin 《International Journal of Ophthalmology(English edition)》 2025年第9期1718-1729,共12页
AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to e... AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to examine associations between myopia and various dietary factors.MR analysis,incorporating both univariable and multivariable approaches,assessed the impact of food intake on myopia risk through five analytical methods,with inverse variance weighted(IVW)serving as the primary reference.Sensitivity analyses,including heterogeneity assessment,horizontal pleiotropy evaluation,and leave-oneout analysis,were conducted to validate the MR findings.RESULTS:Univariable MR analysis identified a causal link between food intake and myopia.Consumption of breaded fish,canned soup,sweet biscuits,and certain fruits correlated with a lower risk of myopia,whereas intake of low-calorie hot chocolate and cereal was associated with an increased risk.Multivariable MR analysis further confirmed that breaded fish consumption exerted a direct protective effect against myopia,particularly when consumed alongside other dietary components.These findings highlight the intricate interplay between specific dietary factors and myopia development,offering valuable insights for further research.CONCLUSION:MR analysis provides evidence supporting a potential causal relationship between breaded fish intake and myopia,underscoring its relevance in targeted myopia prevention strategies. 展开更多
关键词 MYOPIA genome-wide association study food intakes univariable Mendelian randomization analysis multivariable Mendelian randomization analysis
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Metabolic associated steatotic liver disease in Qatar:Analysis of dietary patterns and nutrient intake
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作者 Joud Alalwani Moutaz Derbala +1 位作者 Reema Tayyem Maya Bassil 《World Journal of Hepatology》 2025年第11期255-269,共15页
BACKGROUND Metabolic dysfunction-associated steatotic liver disease(MASLD)is a common and increasingly prevalent condition in the Middle East,but its determinants in the region are underexplored.Diet and lifestyle are... BACKGROUND Metabolic dysfunction-associated steatotic liver disease(MASLD)is a common and increasingly prevalent condition in the Middle East,but its determinants in the region are underexplored.Diet and lifestyle are known to significantly influence MASLD progression.AIM To assess energy and nutrient intake among MASLD patients living in Qatar and evaluate their dietary patterns.METHODS Using a cross-sectional design,94 Arab patients with MASLD,aged≥18 years,living in Qatar were studied.MASLD was diagnosed using ultrasonography,fibro scan,or elastography.Sociodemographic information was collected using a self-administered questionnaire.Dietary intake was assessed through three 24-hour recalls and a qualitative food frequency questionnaire.Energy,macro-,and micronutrient intake were analyzed using Elizabeth Stewart Hands and Associates Food Processor®Nutrition Analysis software.Statistical analyses,including factor loadings were performed using STATA 18.RESULTS Compared to recommended dietary allowance,MASLD patients had high intakes of fat,saturated fat,and cholesterol.They also showed reduced intakes of vitamin K in men,and vitamins E and A(retinol),calcium and magnesium in both genders,while selenium and sodium intakes were higher than recommendations.Three dietary patterns were identified:The‘Traditional Qatari food’pattern,the‘Prudent’pattern,and the‘Fast-food’pattern.However,no significant associations were found between these dietary patterns and body mass index or low-density lipoprotein,using adjusted regression models.CONCLUSION Findings warrant replication in longitudinal studies and call for dietary interventions to reduce energy density and enhance overall diet quality,including micronutrient intake,for MASLD prevention and management in the region. 展开更多
关键词 Metabolic-associated steatotic liver disease Non-alcoholic fatty liver Nutrient intakes Dietary patterns Body mass index Low-density lipoprotein
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Validation and Reproducibility of an Iodine-specific Food Frequency Questionnaire for Evaluating Dietary Iodine Intake in the Elderly Population of Gansu Province,China
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作者 Qi Jin Tao Wang +8 位作者 Meina Ji Jizun Wang Xing Ma Xinyi Wang Jiaqi Wang Hexi Zhang Yanling Wang Wenxing Guo Wanqi Zhang 《Biomedical and Environmental Sciences》 2025年第9期1168-1172,共5页
Iodine is an essential element for the synthesis of thyroid hormones.Iodine deficiency increases the burden on thyroid function and causes harm to health.The identification of convenient and reliable biomarkers for as... Iodine is an essential element for the synthesis of thyroid hormones.Iodine deficiency increases the burden on thyroid function and causes harm to health.The identification of convenient and reliable biomarkers for assessing iodine nutritional status is essential for evaluating iodine intake.Urinary iodine concentration(UIC)is commonly used for population level iodine status assessment but is less reliable for individuals.A 24-h urine sample is more accurate but difficult to collect[1].Thyroid volume(Tvol)and goiter rate are suitable for evaluating the long-term iodine nutritional status in populations[2].Blood indicator collection is an invasive procedure. 展开更多
关键词 goiter rate dietary iodine intake urinary iodine concentration iodine specific food frequency questionnaire thyroid volume synthesis thyroid hormonesiodine elderly population iodine concentration uic
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Laser Measurement and Intensity Evaluation of Intake Swirl in Engine Using a Water Analog 被引量:4
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作者 孙柏刚 李向荣 杜巍 《Journal of Beijing Institute of Technology》 EI CAS 2000年第4期391-396,共6页
The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simul... The intake swirl in the cylinder was induced by a swirler which was fixed in one of two intake ports. In order to understand the characteristics of the intake swirl, a transparent water analog was designed which simulated 150 type single cylinder engine. At the same time, the particle image velocimetry was used to measure the flow fields induced by various swirlers in the analog. After measurement, a new method was presented to evaluate the intensity of the intake swirl. Then, when the measured sections, the lifts of valve and the swirlers were different, the calculated results of the flow field were compared. 展开更多
关键词 diesel engine intake swirl water analog particle image velocimetry MEASUREMENT
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From Input to Output-Exploring the Role of Intake in English Learning
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作者 黄志红 《山东师范大学外国语学院学报(基础英语教育)》 2007年第4期7-17,54,共12页
This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not t... This paper aims to explore the role of intake in second language learning.Based on her literature review and the case of an English lesson in a Chinese secondary school,the author argues that L2 acquisition does not take place directly from input to output.In each sqecific part of L2 acquisition process,intake plays various important roles such as filtering,facilitating in comprehensible input and processing in pushed output.In the Chinese foreign language teaching context,it is also found that L2 acquisition is an arduous task for learners to extract information from the input,utilize it in forming a grammar and produce target language forms accurately and fluently.It is the same with L2 teachers who need to play their roles of a controller,a corrector,an organizer and a prompter in the learning process. 展开更多
关键词 英语教学 第二语言习得 中学 输入 输出 消化吸收
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Gating system optimization of low pressure casting A356 aluminum alloy intake manifold based on numerical simulation 被引量:15
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作者 Jiang Wenming Fan Zitian 《China Foundry》 SCIE CAS 2014年第2期119-124,共6页
To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on fi lling and solidifi cation processes of the casting was carried out using the Pr... To eliminate the shrinkage porosity in low pressure casting of an A356 aluminum alloy intake manifold casting, numerical simulation on fi lling and solidifi cation processes of the casting was carried out using the ProCAST software. The gating system of the casting is optimized according to the simulation results. Results show that when the gating system consists of only one sprue, the fi lling of the molten metal is not stable; and the casting does not follow the sequence solidifi cation, and many shrinkage porosities are observed through the casting. After the gating system is improved by adding one runner and two in-gates, the fi lling time is prolonged from 4.0 s to 4.5 s, the fi lling of molten metal becomes stable, but this casting does not follow the sequence solidifi cation either. Some shrinkage porosity is also observed in the hot spots of the casting. When the gating system was further improved by adding risers and chill to the hot spots of the casting, the shrinkage porosity defects were eliminated completely. Finally, by using the optimized gating system the A356 aluminum alloy intake manifold casting with integrated shape and smooth surface as well as dense microstructure was successfully produced. 展开更多
关键词 low pressure casting A356 aluminum alloy numerical simulation OPTIMIZATION intake manifold
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Association of Red Meat Usual Intake with Serum Ferritin and the Risk of Metabolic Syndrome in Chinese Adults: A Longitudinal Study from the China Health and Nutrition Survey 被引量:5
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作者 HUANG Li Na WANG Hui Jun +4 位作者 WANG Zhi Hong ZHANG Ji Guo JIA Xiao Fang ZHANG Bing DING Gang Qiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第1期19-29,共11页
Objective The present study aimed to investigate the association of red meat usual intake with metabolic syndrome(Met S),and explore the contribution of red meat usual intake to serum ferritin.Methods Based on the dat... Objective The present study aimed to investigate the association of red meat usual intake with metabolic syndrome(Met S),and explore the contribution of red meat usual intake to serum ferritin.Methods Based on the data from the longitudinal China Health and Nutrition Survey(CHNS),2,797 healthy adults aged 18–75 years without hypertension,diabetes,and Met S were selected in 2009 as subjects and follow-up studies were carried out till 2015.We used the National Cancer Institute(NCI)method to estimate the usual intake of foods.Multivariable logistic regressions were performed to evaluate the association between red meat usual intake and the risk of Met S.Quantile regression analysis was used to study the relationship between red meat consumption and serum ferritin levels.Results After adjusting for potential confounders,red meat,and fresh red meat were positively associated with the risk of Met S(RR=1.41,95%CI:1.05–1.90 and RR=1.37,95%CI:1.02–1.85,respectively).These relationships showed increasing trend(P<0.05).The level of serum ferritin increased significantly with the number of Met S components(P<0.05).The quantile regression analysis showed that red meat and fresh red meat usual intake had a significant positive association with serum ferritin levels across the entire conditional serum ferritin distribution(P<0.05).Processed red meat did not exhibit a similar association.Conclusion Higher red meat usual intake was associated with an increased risk of Met S and elevated serum ferritin levels. 展开更多
关键词 Usual intake Red MEAT METABOLIC syndrome SERUM FERRITIN
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Association of Dietary Carotenoids Intake with Skeletal Fluorosis in the Coal-burning Fluorosis Area of Guizhou Province 被引量:8
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作者 LIU Jun YANG Sheng +3 位作者 LUO Ming Jiang ZHAO Xun ZHANG Yuan Mei LUO Ya 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第6期438-447,共10页
Objective To explore whether the intake of dietary carotenoids could protect against skeletal fluorosis in Guizhou province in which coal-burning fluorosis is endemic. Methods A case-control study of 196 patients with... Objective To explore whether the intake of dietary carotenoids could protect against skeletal fluorosis in Guizhou province in which coal-burning fluorosis is endemic. Methods A case-control study of 196 patients with skeletal fluorosis and 196 age and gender-matched controls was conducted in Zhijin, Guizhou Province. Face-to-face interviews were conducted to assess habitual dietary intake using a 75-item food frequency questionnaire and various covariates with structured questionnaires. Urinary fluoride was measured using an ion-selective electrode method. The genotype of superoxide dismutase 2(SOD2) rs11968525 was detected by Taq Man method. Results We observed significant dose-dependent inverse associations of skeletal fluorosis with intake of β-carotene, lutein/zeaxanthin, lycopene, and total carotenoids(P-trend = 0.002 to 0.018), whereas α-carotene and β-cryptoxanthin intakes were not found to be related to skeletal fluorosis, after adjustment for potential confounders. The adjusted ORs and 95% CI of skeletal fluorosis for the highest versus lowest quartile were 0.30(0.10, 0.86) for β-carotene, 0.23(0.08, 0.66) for lycopene, 0.26(0.10, 0.75) for lutein/zeaxanthin and 0.34(0.14, 0.74) for total carotenoids(all P-trend &lt; 0.05). Stratified analyses showed that the protective effects of lutein/zeaxanthin and total carotenoids on skeletal fluorosis were more evident for individuals with the AG+AA genotypes of SOD2(rs11968525). Conclusion Increased intakes of β-carotene, lutein/zeaxanthin, lycopene, and total carotenoids are independently associated with a lower risk of coal-burning skeletal fluorosis. SOD2(rs11968525) polymorphisms might modify the inverse associations between dietary carotenoids and skeletal fluorosis. 展开更多
关键词 Case-control study Dietary intake Carotenoids Skeletal fluorosis
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Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake 被引量:6
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作者 Yunyi Xie Zezhong Wu +1 位作者 Diming Wang Jianxin Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第4期1059-1066,共8页
Background: Residual feed intake(RFI) is an inheritable measure of feed efficiency that is independent on level of production. However, physiological and metabolic mechanisms underlying divergent RFI are not fully elu... Background: Residual feed intake(RFI) is an inheritable measure of feed efficiency that is independent on level of production. However, physiological and metabolic mechanisms underlying divergent RFI are not fully elucidated.This study was conducted to investigate dietary nitrogen(N) partitioning and microbial protein synthesis in lactating dairy cows divergent in phenotypic RFI.Results: Thirty Holstein dairy cows(milk yield = 35.3 ± 4.71 kg/d;milk protein yield = 1.18 ± 0.13 kg/d;mean ± standard deviation) were selected for the experiment to derive RFI. After the RFI measurement period of 50 d, the 10 lowest RFI cows and 8 highest RFI cows were selected. The low RFI cows had lower dry matter intake(DMI, P < 0.05) than the high RFI cows, but they produced similar energy-corrected milk. The ratios of milk to DMI(1.41 vs. 1.24, P < 0.01) and energy-corrected milk to DMI(1.48 vs. 1.36, P < 0.01) were greater in low RFI cows than those in the high RFI cows. The low RFI cows had lower milk urea nitrogen than that in the high RFI cows(P = 0.05). Apparent digestibility of nutrients did not differ between two groups(P > 0.10). Compared with high RFI animals, the low RFI cows had a lower retention of N(5.72 vs. 51.4 g/d, P < 0.05) and a higher partition of feed N to milk N(29.7% vs. 26.5%, P < 0.05).Conclusions: The results suggest that differences in N partition, synthesis of microbial protein, and utilization of metabolizable protein could be part of the mechanisms associated with variance in the RFI. 展开更多
关键词 Lactating COWS MICROBIAL protein Nitrogen partitioning RESIDUAL FEED intake
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Intake of Volatile N-nitrosamines and Their Ability to Exogenously Synthesize in the Diet of Inhabitants from High-risk Area of Esophageal Cancer in Southern China 被引量:7
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作者 LINKUN SHENZHONG-YING 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第4期277-282,共6页
Objective Nan'ao County in Guandong Province is a high-risk area of esophageal cancer in Southern China. Of the suspected etiological factors in the environment, N-nitrosamines and their precursors have received t... Objective Nan'ao County in Guandong Province is a high-risk area of esophageal cancer in Southern China. Of the suspected etiological factors in the environment, N-nitrosamines and their precursors have received the greatest attention. Methods Sixty samples of the diet ingested by the inhabitants were collected and detected for volatile N-nitrosamines and their precursors. Five N-nitrosamines detected by Gas Chromatography-Thermal Energy Analyzer were N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopyrrolidine, N-nitrosopiperidine and N-nitrosomethyl-benzylamine. Results The average content of 5 volatile N-nitrosamines in the diet was 312.0 μg/kg (median). The daily intake of the nitrosamines was 286.5 μg/head/day. Only the ability to exogenously synthesize N-nitrosopiperidine was powerful among 5 volatile N-nitrosamines. By a computerized stepwise regression analysis and curve fitting, we studied the correlation among the nitrosamines, the precursors and the major food items in the samples. Conclusion It demonstrated that a relatively high content of volatile N-nitrosamines was present in the diet collected in the area. 展开更多
关键词 Volatile nitrosamines intake Exogenous synthesis Esophageal cancer
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