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Boxing Practitioners Physiology Review: 3. Dietary Supplementation, Weight Control, Recovery and Altitude
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作者 André Mukala Nsengu Tshibangu 《Open Journal of Molecular and Integrative Physiology》 2024年第1期1-29,共29页
The preceding parts of the review concerned kinanthropometric parameters, skeletal muscle recruitment, ergometry, systemic responses and adaptations. Main teachings of this third part of the whole review follow. At th... The preceding parts of the review concerned kinanthropometric parameters, skeletal muscle recruitment, ergometry, systemic responses and adaptations. Main teachings of this third part of the whole review follow. At the 1996 Atlanta Olympic Game, most vitamin users (91 percent) were boxers. After 18 days of endurance training at the altitude of 1800 m, in boxers, 1) erythropoietin and reticulocytes values increased, 2) remained unchanged parameters of iron metabolism and maximal oxygen uptake values, 3) iron supplementation decreased total body hemoglobin values. Zinc supplementation and/or regularity while boxing influenced plasma levels of calcium, copper, iron, magnesium, phosphorus and zinc in boxers. Sodium bicarbonate ingestion increased punches frequency and time to fatigue in boxers. Boxing-induced thermal dehydration yielded 1) body and muscle masses decrease compensated by increased neural input to muscle, to maintain muscle strength, but 2) a 26.8 percent performance fall. In boxers, fluid and food intake restriction 1) changed neither blood vitamin status nor plasma glutathione levels, 2) yielded a) a negative mood profile and a performance decrease, when resulted in body mass fall by 5.16 percent but b) no performance decrease when fall was by three percent. Diet protein or protein and caloric components decrease increased, in boxers, protein catabolism and, for the same submaximal workload, heart rate and oxygen intake. In food-restricted boxers, myoprotein catabolism increased with decreasing meal intake frequency. Competition and no-competition boxers utilize massage. Massage increased perceptions of recovery after a whole boxing performance. High level of cardiorespiratory fitness accelerates recovery process between boxing rounds. 展开更多
关键词 boxing Integrative Physiology Martial Arts Molecular Physiology Musculoskeletal Physiology
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Strategies for Boxing Teaching in Competitive Sports Schools
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作者 Yu Huang 《Journal of Contemporary Educational Research》 2024年第7期258-263,共6页
To improve the quality of boxing teaching in competitive sports schools,it is necessary to first analyze the strengths and weaknesses of boxing teaching in competitive sports schools,and then optimize the teaching str... To improve the quality of boxing teaching in competitive sports schools,it is necessary to first analyze the strengths and weaknesses of boxing teaching in competitive sports schools,and then optimize the teaching strategy.The strategies include innovating the boxing curriculum system and content,building learning communities inside and outside the classroom,personalizing the teaching forms and methods,using multimedia to broaden the teaching path,focusing on the integration of boxing teaching leagues,and diversifying the teaching incentives and evaluations. 展开更多
关键词 Competitive sports schools boxing Teaching strategies
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Box-Behnken响应面法结合层次分析法优化萸仙茅炮制工艺
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作者 徐国伟 王巍 +3 位作者 刘思翰 洪艺丹 张立强 鞠成国 《中国中医药信息杂志》 CAS 2025年第1期134-139,共6页
目的优选萸仙茅炮制工艺。方法在单因素试验基础上,以料液比、炒制时间和炒制温度为影响因素,以仙茅苷、苔黑酚葡萄糖苷、苔黑酚龙胆二糖苷含量及外观性状的综合评分为评价指标,利用Box-Behnken响应面法结合层次分析法优化萸仙茅最佳炮... 目的优选萸仙茅炮制工艺。方法在单因素试验基础上,以料液比、炒制时间和炒制温度为影响因素,以仙茅苷、苔黑酚葡萄糖苷、苔黑酚龙胆二糖苷含量及外观性状的综合评分为评价指标,利用Box-Behnken响应面法结合层次分析法优化萸仙茅最佳炮制工艺,并进行工艺验证。结果萸仙茅最佳炮制工艺为:取生仙茅饮片,加入等量吴茱萸汁拌匀,置密闭容器内,闷润至药汁被完全吸尽,于130℃炒制6min,取出,60℃干燥。每100kg仙茅用吴茱萸10kg。吴茱萸汁制法:取吴茱萸10kg,加12倍量水浸泡60min,煎煮50min,提取3次,合并滤液,浓缩至100kg。结论本研究优化所得萸仙茅的炮制工艺可行、稳定。 展开更多
关键词 萸仙茅 box-Behnken响应面法 层次分析法 炮制工艺
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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基于Box-Behnken设计-响应面法优化调肝活血稳压颗粒提取工艺及其质量标准的研究
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作者 李凡 张国松 +4 位作者 魏鑫华 贾超 夏明艳 李东勲 张文锍 《陕西中医药大学学报》 2025年第1期100-106,共7页
目的优化调肝活血稳压颗粒的提取工艺,并对其质量标准进行研究。方法本研究以浸膏得率及丹酚酸B的转移率的综合评分为指标,采用单因素考察结合Box-Behnken设计-响应面法优化调肝活血稳压颗粒的提取工艺,采用薄层色谱法对方中药材进行鉴... 目的优化调肝活血稳压颗粒的提取工艺,并对其质量标准进行研究。方法本研究以浸膏得率及丹酚酸B的转移率的综合评分为指标,采用单因素考察结合Box-Behnken设计-响应面法优化调肝活血稳压颗粒的提取工艺,采用薄层色谱法对方中药材进行鉴别。结果确定最终提取工艺为:第一次加入10倍量水煎煮90 min,第二次加入6倍量水煎煮60 min。测定方法结果准确可靠。薄层色谱法检测出天麻、栀子、丹参等三味中药的特征性斑点。结论优化后的提取工艺操作简单,提取效果良好,结果稳定可靠。 展开更多
关键词 调肝活血稳压颗粒 丹酚酸B 薄层色谱法 高效液相色谱法 box-Behnken设计-响应面法
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Plackett-Burman联用Box-Behnken响应面法优选伤痛凝胶贴膏基质处方的研究
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作者 钱珊珊 李舒寒 +3 位作者 杨满琴 谢若男 桂双英 彭成军 《牡丹江医科大学学报》 2025年第1期118-122,162,共6页
目的优选伤痛凝胶贴膏基质处方的配比。方法在单因素试验基础上,采用Plackett-Burman联用Box-Behnken响应面法,以感官评价、初黏力、持黏力作为伤痛凝胶贴膏的综合评价指标,优选伤痛凝胶贴膏基质处方。结果优选的伤痛凝胶贴膏基质处方为... 目的优选伤痛凝胶贴膏基质处方的配比。方法在单因素试验基础上,采用Plackett-Burman联用Box-Behnken响应面法,以感官评价、初黏力、持黏力作为伤痛凝胶贴膏的综合评价指标,优选伤痛凝胶贴膏基质处方。结果优选的伤痛凝胶贴膏基质处方为NP-7002.82 g,甘羟铝0.15 g,甘油11.02 g,PVPK902.50 g,高岭土0.50 g,酒石酸0.14 g。结论优选的伤痛凝胶贴膏有很好的黏性和成型性,顺应性好,便于临床推广使用。 展开更多
关键词 伤痛凝胶贴膏 基质处方 PLACKETT-BURMAN box-Behnken
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基于Box-Behnken设计-响应面法优化败毒止泻提取物制备工艺研究
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作者 房思远 赵兵令 +2 位作者 郗艳菊 朱永明 李辰荃 《中兽医医药杂志》 2025年第1期73-79,共7页
为探索败毒止泻提取物的合理提取工艺,提高秦皮甲素和秦皮乙素总含量以及复方浸出物出膏率,选择影响试验指标的提取次数、提取时间、加水量等3个核心因素进行单因素试验,以最优单因素为影响因子,采用Box-Behnken中心组合设计建立数学模... 为探索败毒止泻提取物的合理提取工艺,提高秦皮甲素和秦皮乙素总含量以及复方浸出物出膏率,选择影响试验指标的提取次数、提取时间、加水量等3个核心因素进行单因素试验,以最优单因素为影响因子,采用Box-Behnken中心组合设计建立数学模型,考察相关参数对综合评分的影响程度。结果表明,败毒止泻提取物的最佳提取条件为提取3次,提取时间为1.5 h,加水量为12倍水;模型预测综合评分为96.932,验证值为96.757,理论值与验证值相对误差为0.18%。优化后的败毒止泻提取物标准工艺为中试生产转化以及临床使用的顺应性奠定了基础。 展开更多
关键词 败毒止泻提取物 box-Behnken响应面法 综合评分
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Evaluation of Ability of Two Different Pneumatic Boxing Gloves to Reduce Delivered Impact Forces and Improve Safety 被引量:3
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2018年第2期457-491,共35页
Two prototype pneumatic boxing gloves of different design were compared against conventional 10?oz (Std 10?oz) and 16?oz (Std 16?oz) gloves in terms of ability to reduce impact forces delivered to a target. One of the... Two prototype pneumatic boxing gloves of different design were compared against conventional 10?oz (Std 10?oz) and 16?oz (Std 16?oz) gloves in terms of ability to reduce impact forces delivered to a target. One of the pneumatic gloves (SBLI) contained a sealed air bladder inflated to a pressure of 2?kPa. The other (ARLI) incorporated a bladder that allowed release of air to the external environment upon contact with a target, followed by rapid air reuptake. Each glove was placed on to a mechanical fist and dropped 10 times on to an in-floor force plate from each of nine heights ranging from 1.0 to 5.0 metres, with the 5-metre drop generating a peak pre-impact glove velocity close to the reported maximum for elite boxers. Compared to the conventional gloves, the ARLI glove substantially reduced peak impact forces at all drop heights, with the reduction exceeding 30% even at the 5-metre level. The SBLI glove was as effective as the ARLI glove in reducing peak impact forces at drop heights of up to 2.5 metres, but its performance then progressively diminished, and at drop heights of 4.0, 4.5 and 5.0 metres it produced peak force readings similar to those recorded for the Std 10?oz and Std 16?oz gloves. The superiority of the ARLI glove was even more evident in relation to peak rate of force development, with reductions relative to the Std 10?oz glove being ~60% at drop heights up to 3.5 metres and still ~47% at 5 metres. Peak rate of force development for the SBLI glove exceeded that for the ARLI glove for all drop heights of 2.0 metres and above, and at 4.0, 4.5 and 5.0 metres it was higher than the readings for the Std 10 oz and 16?oz gloves. The protective effect of the ARLI glove was?associated with an increase in impact compliance and prolongation of contact time between glove and target. It is concluded that a pneumatic boxing glove that provides for air exchange with the external environment can greatly reduce impact magnitudes across the whole range of pre-impact glove velocities likely to be encountered in boxing, thereby mitigating risks associated with the sport. While acceptance of the gloves by the boxing community is uncertain, opportunity may exist for almost immediate uptake in modified boxing programs. 展开更多
关键词 boxing boxing SAFETY box’Tag Modifed boxing Modbox PNEUMATIC box-ing GLOVE SPORT Technology
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Depositional Environment of Es_4~u and Es_3~l Shales Based on Biomarkers from the Boxing Sag of Dongying Depression, East China 被引量:1
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作者 WANG Ying LIU Luofu +3 位作者 MENG Jianghui JIANG Zhenxue GAO Yongjin LIU Shuhui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第5期1556-1564,共9页
The Boxing Sag is located in the southwest of Dongying Depression, southern Bohai Bay Basin of East China. It is one of the main petroliferous sags in the Dongying Depression, and has two major source rocks, namely th... The Boxing Sag is located in the southwest of Dongying Depression, southern Bohai Bay Basin of East China. It is one of the main petroliferous sags in the Dongying Depression, and has two major source rocks, namely the upper 4th Member (Es4u) and lower 3rd Member (Es31) shales of Eocene Shahejie Formation, which are the new exploration targets in recent years. In this study, 16 core samples were collected from Es4u and Es31 shales in the Boxing Sag, and the saturate hydrocarbons were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), respectively. The results show that Es4u shale has obvious phytane and gammacerane predominance, higher concentration of tricyclic terpanes and regular steranes, and very low concentration of 4- methly steranes; Es31 shale has pristane predominance, lower concentration of tricyclic terpanes, gammacerane and regular steranes, and higher concentration of 4-methly steranes. The Es4u shale can be further divided into two types based on the distribution of n-alkanes in gas chromatograms: normal distribution and double peak pattern. The biomarker characteristics and sedimentary facies distribution show that Es4u shale was deposited in the saline-hypersaline semi-deep (Type A Es4u shale, sag center) to shallow (Type B Es4u shale, sag edge) lacustrine environments, Es31 shale was deposited in the freshwater-brackish semi-deep-deep lacustrine environments, and the former sedimentary facies maps of Es4u and Es31 in the Boxing Sag are further modified. 展开更多
关键词 BIOMARKER lacustrine environment SHALE Shahejie Formation boxing Sag Dongying Depression
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基于Box-Behnken设计-响应面法优化酒黄精炮制工艺
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作者 罗诚 蔡文菲 +4 位作者 张阿凤 汪晨怡 代安琳 胡菊 万军 《安徽医药》 CAS 2024年第10期1930-1934,I0001,共6页
目的采用Box-Behnken设计-响应面法(Box-Behnken design-response surface method,BBD-RSM)对黄精炮制工艺进行优化,筛选最佳工艺参数。方法研究于2023年1—5月开展。以黄精外观性状、醇浸出物、多糖含量等为评价指标,基于单因素试验进... 目的采用Box-Behnken设计-响应面法(Box-Behnken design-response surface method,BBD-RSM)对黄精炮制工艺进行优化,筛选最佳工艺参数。方法研究于2023年1—5月开展。以黄精外观性状、醇浸出物、多糖含量等为评价指标,基于单因素试验进行响应面综合实验,运用BBD-RSM,探索黄精饮片润制时间、蒸制时间、焖制时间等对其品质的影响,优选炮制工艺参数及炮制设备。结果通过拟合模型,外观性状评分、醇浸出物含量、黄精多糖含量预测值分别为72.31分、64.86%、12.96%,优选黄精最佳酒制工艺为润制时间1.5 h、蒸制时间5.5 h、焖制时间1.0 h;蒸制设备拟选用回转式蒸药机,干燥设备拟选用敞开式烘干箱。结论所优选酒黄精炮制工艺合理、可行,为酒黄精炮制生产工艺及设备选型提供了依据。 展开更多
关键词 黄精 酒制工艺 box-BEHNKEN设计 响应面法 炮制设备
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基于Box-Behnken响应面法优化方便藜麦粥制备工艺
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作者 郑守晶 黄思梅 +2 位作者 岳文杰 黄子建 郑明锋 《武夷科学》 2024年第1期73-80,共8页
以复水率、复水时间和感官品质为指标,通过单因素试验优选方便藜麦粥的最佳浸泡温度、料水比和蒸煮时间;利用Box-Behnken响应面法优化其制备工艺,并采用加权法计算综合得分。结果表明,最佳制备工艺为浸泡温度41℃,料水比1∶9,蒸煮时间23... 以复水率、复水时间和感官品质为指标,通过单因素试验优选方便藜麦粥的最佳浸泡温度、料水比和蒸煮时间;利用Box-Behnken响应面法优化其制备工艺,并采用加权法计算综合得分。结果表明,最佳制备工艺为浸泡温度41℃,料水比1∶9,蒸煮时间23 min。经验证试验,其综合得分为96.08,与理论预测值(96.43)的相对偏差为0.35%(<5.0%)。优化的方便藜麦粥制备工艺为其开发应用提供重要支撑。 展开更多
关键词 藜麦 方便粥 box-Behnken响应面法 制备工艺
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Box-Behnken响应面法优化葛根异黄酮提取纯化工艺及损伤心肌细胞治疗作用研究
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作者 蔡琳 《山东化工》 CAS 2024年第2期9-13,20,共6页
目的:采用Box-Behnken响应面优化葛根异黄酮最佳提取工艺,并研究葛根异黄酮对损伤心肌细胞的治疗作用。方法:在单因素实验的基础上,以料液比、提取时间、溶剂浓度为考察因素,以3'-羟基葛根素、葛根素、3'-甲氧基葛根素、大豆苷... 目的:采用Box-Behnken响应面优化葛根异黄酮最佳提取工艺,并研究葛根异黄酮对损伤心肌细胞的治疗作用。方法:在单因素实验的基础上,以料液比、提取时间、溶剂浓度为考察因素,以3'-羟基葛根素、葛根素、3'-甲氧基葛根素、大豆苷的含量为评价指标,采用Box-Behnken响应面法设计实验,以葛根异黄酮总提取率为考察指标,通过分析回归方程模型,优选最佳提取工艺并验证工艺;采用MTT法检测葛根异黄酮对损伤心肌细胞的治疗作用。结果:Box-Behnken响应面法优化得到葛根异黄酮最佳提取工艺为:料液比为30 mg·mL^(-1),提取时间为100 min,乙醇体积分数为73%,葛根异黄酮的总提取率平均值为41.6 mg·g^(-1),与预测值42.08 mg·g^(-1),相对误差0.81%;葛根异黄酮对H 2O_(2)损伤的缺氧复氧模型和Na 2S_(2)O 4损伤的缺血再灌注模型OD值分别为0.7436±0.0292和0.7457±0.0094,细胞存活率分别为81.32%和73.41%。结论:优选葛根抗氧化活性异黄酮最佳工艺稳定,预测模型效果良好,且葛根异黄酮对心肌缺血有良好的治疗作用。 展开更多
关键词 葛根异黄酮 box-Behnken 提取率 提取工艺 损伤心肌细胞
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Pneumatic Boxing Glove Reduces Upward Drift in Peak Force and Loading Rate over a Long Series of Impacts
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2019年第1期18-53,共36页
A conventional boxing glove and a prototype pneumatic glove were each fitted to a mechanical fist and dropped 253 times from a height of 3 metres on to a force plate covered by an ethylene vinyl acetate (EVA) mat. Imp... A conventional boxing glove and a prototype pneumatic glove were each fitted to a mechanical fist and dropped 253 times from a height of 3 metres on to a force plate covered by an ethylene vinyl acetate (EVA) mat. Impact dynamics were measured and modelled. From the outset, peak impact force and peak rate of force development (loading rate) were lower for the pneumatic glove. For both gloves, these variables displayed upward drift during the drop series, but the drift was smaller for the pneumatic glove. Consequently, the magnitude of the protective effect provided by the pneumatic glove increased with the number of impacts. For the conventional glove, change in peak force showed a close inverse relationship to force plate contact time (R2?>?0.96) and the time from first contact of the glove with the force plate to attainment of peak force (R2?=?0.85). These relationships were much weaker for the pneumatic glove (R2?=?0.09 and 0.59 respectively), suggesting the possibility of a more complex impact damping mechanism. Following the 253 drops of the pneumatic glove, the EVA mat covering the force plate was replaced, and another 10 drops then performed. Peak force readings were immediately reduced to an extent suggesting that 26%?-?34% of the increase that had occurred over the 253 drops was attributable to impact-induced change in mat properties. This has implications for future experimental designs. Overall, the findings provided further evidence of the potential of pneumatic gloves to enable safer boxing. 展开更多
关键词 boxing SAFETY Low-Impact boxing GLOVES Modified boxing PNEUMATIC boxing GLOVES Protective Equipment for boxing SPORT Technology SPORT SAFETY
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多指标综合评分法结合Box-Behnken响应面法优选栀子茯苓压片糖果的提取工艺
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作者 邓刚 梁可文 蒋婳影 《化工科技》 CAS 2024年第3期40-45,共6页
以提取液中栀子苷含量及干膏率作为考察指标,在单因素试验基础上采用直接回流提取法、多指标综合评分法结合Box-Behnken响应面法考察了乙醇浓度、提取时间和料液比3个因素对提取工艺的影响。结果表明,制剂的最佳提取工艺为乙醇浓度75%,... 以提取液中栀子苷含量及干膏率作为考察指标,在单因素试验基础上采用直接回流提取法、多指标综合评分法结合Box-Behnken响应面法考察了乙醇浓度、提取时间和料液比3个因素对提取工艺的影响。结果表明,制剂的最佳提取工艺为乙醇浓度75%,提取时间120 min,料液比17倍,栀子苷平均含量为3.17%,平均干膏率为11.33%,综合评分平均值为98.30(n=3,RSD=0.18%)。该工艺合理可行,有效成分提取率高,适合大规模生产。 展开更多
关键词 栀子茯苓压片糖果 多指标综合评分法 box-Behnken响应面法 提取工艺
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Performance of Prototype Pneumatic Boxing Gloves under Two Different Conditions of Target Padding
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2018年第3期603-624,共22页
The impact damping capabilities of four different boxing gloves were assessed under two different conditions of target padding to determine whether target characteristics might influence previous conclusions concernin... The impact damping capabilities of four different boxing gloves were assessed under two different conditions of target padding to determine whether target characteristics might influence previous conclusions concerning potential for impact mitigation through novel glove design. A conventional 10?oz glove (Std 10?oz), a conventional 16?oz glove (Std 16?oz), a prototype pneumatic glove with a sealed bladder (SBLI) and a prototype pneumatic glove with a bladder allowing air exchange with the external environment (ARLI) were each dropped three times on to a force plate from six heights ranging from 2.5 to 5.0 metres. The force plate was covered by a 50 mm thick mat of EVA material and results obtained were compared with those of an earlier experiment involving use of a similar protocol but a 25 mm thick EVA force plate covering. The thicker mat greatly reduced peak impact forces for all gloves, with values for the Std 10?oz glove becoming much closer to those reported by other researchers for punches delivered by elite boxers to crash test manikins. Peak rates of force development were also substantially decreased. Protective effects provided by the ARLI glove relative to the Std 10?oz glove were diminished but still in the order of 17%?-?22% for peak impact force and 27%?-?49% for peak rate of force development across the range of drop heights. With the 50 mm mat thickness, the SBLI glove was as effective as the ARLI glove in reducing peak impact force, whereas this was not the case with the 25 mm mat. It was, however, always inferior to the ARLI glove in decreasing peak rate of force development. The ability of the ARLI glove to afford protection across a spectrum of impact conditions could yield important practical advantages. 展开更多
关键词 boxing SAFETY Low-Impact boxing GLOVES Modified boxing Protective Equipment for boxing SPORT Technology SPORT SAFETY
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Box-Behnken响应面法优选紫斑牡丹中丹皮酚和芍药苷提取工艺 被引量:3
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作者 周坤 付永莉 +2 位作者 罗婷 罗星 吴春芳 《中国药业》 2024年第3期68-73,共6页
目的优选紫斑牡丹中丹皮酚和芍药苷的提取工艺。方法在单因素试验基础上,以液料比、提取时间和乙醇体积分数为影响因素,以丹皮酚和芍药苷提取率的总权重综合评分为评价指标,采用Box-Behnken响应面法优选最佳提取工艺,并进行验证试验。... 目的优选紫斑牡丹中丹皮酚和芍药苷的提取工艺。方法在单因素试验基础上,以液料比、提取时间和乙醇体积分数为影响因素,以丹皮酚和芍药苷提取率的总权重综合评分为评价指标,采用Box-Behnken响应面法优选最佳提取工艺,并进行验证试验。结果最佳提取工艺为液料比28倍,提取时间150 min,乙醇体积分数52%。此工艺条件下,丹皮酚提取率为0.49%(RSD=1.33%,n=3),芍药苷提取率为5.38%(RSD=1.07%,n=3)。结论该提取工艺稳定、可行,可用于紫斑牡丹中丹皮酚和芍药苷的提取。 展开更多
关键词 紫斑牡丹 丹皮酚 芍药苷 box-Behnken响应面法 提取工艺
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Effect of Pneumatic Boxing Gloves on Impact Kinematics and Their Relationship to Impact Forces
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作者 Paul Perkins Alex Jamieson +1 位作者 Wayne Spratford Allan Hahn 《World Journal of Engineering and Technology》 2019年第3期472-512,共41页
This study was aimed at improved understanding of the mechanisms of previously reported protective effects of a pneumatic boxing glove. A Motion Capture System was used to obtain velocity data from four different boxi... This study was aimed at improved understanding of the mechanisms of previously reported protective effects of a pneumatic boxing glove. A Motion Capture System was used to obtain velocity data from four different boxing gloves dropped on to a force plate from nine heights ranging from 1 to 5 metres. Two gloves were of the conventional type but differed in mass. The other two were prototype pneumatic gloves. One of these (SBLI) had a sealed bladder while the other (ARLI) incorporated a port allowing air exchange with the external environment. The pneumatic gloves decelerated more slowly than the conventional gloves following impact and compressed through a greater absolute distance. Consequently, they took longer to reach zero velocity. As drop height increased, these trends became more pronounced for the ARLI glove than the SBLI glove. Increase in velocity during rebound was also slower for the pneumatic gloves. The ARLI glove had a lower coefficient of restitution than any of the other gloves at low to moderate drop heights but not at high drop heights. The SBLI glove had a higher coefficient of restitution than the other gloves at all drop heights from 2 metres upwards. This indicated that, overall, the ARLI glove was the most effective, and the SBLI glove the least effective, in dissipating the kinetic energy of impact through conversion to other energy forms. For all gloves at all drop heights, peak positive acceleration at the beginning of rebound was of lower absolute magnitude than peak negative acceleration at the end of compression. The influence of drop height on an index characterising this relationship differed between the conventional and pneumatic gloves, possibly reflecting structural changes to gloves as impact energy increased. The conventional and pneumatic gloves differed regarding temporal alignment between key kinematic and kinetic events, and there were some differences between the two pneumatic gloves in this respect. Nevertheless, peak glove deceleration correlated highly with peak impact force, not only for each glove individually but also when data for all gloves were combined. The findings confirmed the potential practical utility of the ARLI glove and identified air cushion thickness, glove compressibility and capacity for air release and subsequent reuptake as critical aspects of its design. 展开更多
关键词 PNEUMATIC boxing GLOVES boxing SAFETY Modified boxing SPORT SAFETY SPORT Technology Sports Equipment Design Coefficient of RESTITUTION Elas-tic-Plastic Impacts
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蓝莓B-box型锌指蛋白基因家族的鉴定及其在果实发育期的表达模式 被引量:1
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作者 黄巧玉 杨珺菲 +6 位作者 汪旭祥 陆晓莹 李晓谊 李永强 徐丽珊 宗宇 郭卫东 《浙江师范大学学报(自然科学版)》 CAS 2024年第2期185-195,共11页
B-box(BBX)基因家族成员在植物生长发育中起重要作用.为探究BBX在蓝莓果实成熟发育过程中的作用,通过生物信息学的方法鉴定BBX基因家族成员,并对其进行染色体定位、系统进化关系、基因结构、启动子顺式作用元件及表达模式分析.结果表明... B-box(BBX)基因家族成员在植物生长发育中起重要作用.为探究BBX在蓝莓果实成熟发育过程中的作用,通过生物信息学的方法鉴定BBX基因家族成员,并对其进行染色体定位、系统进化关系、基因结构、启动子顺式作用元件及表达模式分析.结果表明:在蓝莓基因组中鉴定出38个BBX基因成员,基因结构保守,外显子平均个数为3.13,这些基因可分成Ⅰ~Ⅲ3个亚族,不均匀分布于23条染色体;BBX基因的启动子序列中存在光响应、植物激素响应、胁迫响应和植物生长发育等4类顺式作用元件;VcBBX基因成员在‘Star’和‘O’Neal’蓝莓果实发育过程中存在显著性差异表达,VcBBX9,VcBBX16,VcBBX25和VcBBX20在S8表达量最高,VcBBX26在S6表达量最高,VcBBX30在S3表达量最高.研究结果将为进一步探究BBX型锌指蛋白在蓝莓果实发育过程中的功能奠定基础. 展开更多
关键词 蓝莓 B-box 基因家族 果实硬度 基因结构 基因表达量
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一类单调递减正项数列的BOX维数估计
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作者 张云 梁永顺 《理论数学》 2024年第7期275-283,共9页
当使用比较原则、 柯西判别法在讨论正项级数敛散性时,会遇到比值极限为1从而无法使用的情况,典型的例子为数组{1/n}和{1/n2}的正项级数具有不同的敛散性。 本文讨论了形如1/na(α > 0) 正项级数的敛散性与对应点集的BOX维数存在一... 当使用比较原则、 柯西判别法在讨论正项级数敛散性时,会遇到比值极限为1从而无法使用的情况,典型的例子为数组{1/n}和{1/n2}的正项级数具有不同的敛散性。 本文讨论了形如1/na(α > 0) 正项级数的敛散性与对应点集的BOX维数存在一定关联,当点集的BOX维数大于等于1/2时,正项级数发散;小于1/2时,正项级数收敛,同时提出了利用1/n为参照对象判断数列正项级数敛散性的一种新方法。 展开更多
关键词 正项级数 box维数 敛散性
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Boxing Practitioners Physiology Review 1. Kinanthropometric Parameters, Skeletal Muscle Recruitment and Ergometry
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作者 André Mukala Nsengu Tshibangu 《Open Journal of Molecular and Integrative Physiology》 2020年第1期1-24,共24页
Seven percent voluntary body weight decrease by boxers requires 21 days while 4.4 percent increase needs only one day. Energy and fluid intakes reduction does not affect boxers punching force. Boxers effective punch m... Seven percent voluntary body weight decrease by boxers requires 21 days while 4.4 percent increase needs only one day. Energy and fluid intakes reduction does not affect boxers punching force. Boxers effective punch masses and body weights correlate. Wrist girths and competition rankings of boxers correlate. Boxers show leanness body fat percentage. Boxers, generally highly mesomorphic, with increasing body weight, show ectomorphy decreases but endomorphy and mesomorphy increases. Vibration treatment enhances power in boxers arm flexors. Presence, nature and thickness of bandages and gloves donned influence boxers punch force. Stance posture adopted by boxers ends in locomotion functional parameters adaptations. Muscular recruitment sequence during rear straight punches may be influenced by the target height (head or body levels) and the boxer intention (produce maximal force or maximal speed). Handgrip strength: 1) increases from younger to older and from lighter to heavier boxers, and 2) correlates with competition ranking. Rear knee extension increases rear straight punching force to the head. Compared to uppercut and straight punches, the hook produces the highest change in hand velocity. Maximal forces are larger for the rear than the lead hand, and greater in more than in less experienced boxers. Hook punch force is greater than those of uppercut and straight punches. Boxer aim (produce maximum force or maximum speed) influence his punching force. Massage neither prevents a decrement in repeated performance nor has detrimental effects on performance, but increases recovery perceptions, compared with the passive rest intervention. 展开更多
关键词 boxing Integrative PHYSIOLOGY Martial Arts Molecular PHYSIOLOGY MUSCULOSKELETAL PHYSIOLOGY
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