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Mie散射 1

“一带一路”，制造业，六大经济走廊，显性比较优势指数，多维尺度分析 1

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三峡工程 1

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中医理论研究；临床优势评价；中药资源开发与利用；中药智能制造；中医药走向国际 1

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EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 61-72 doi: 10.15302/J-FASE-2022476

摘要：

● Promotion of local sustainable innovation developed by forest farmers.

关键词： agroforestry     forest farmers     local innovation     relative advantage     social forestry    

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HOW MULTISPECIES INTERCROP ADVANTAGE RESPONDS TO WATER STRESS: A YIELD-COMPONENT ECOLOGICAL FRAMEWORK

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 416-431 doi: 10.15302/J-FASE-2021412

摘要：

Absolute yield and land use efficiency can be higher in multicrops. Though this phenomenon is common, it is not always the case. Also, these two benefits are frequently confused and do not necessarily occur together. Cropping choices become more complex when considering that multicrops are subject to strong spatial and temporal variation in average soil moisture, which will worsen with climate change. Intercropping in agroecosystems is expected to buffer this impact by favoring resistance to reduced humidity, but there are few empirical/experimental studies to validate this claim. It is not clear if relatively higher multicrop yield and land use efficiency will persist in the face of reduced soil moisture, and how the relation between these benefits might change. Here, we present a relatively simple framework for analyzing this situation. We propose a relative multicrop resistance (RMR) index that captures all possible scenarios of absolute and relative multicrop overyield under water stress. We dissect the ecological components of RMR to understand the relation between higher multicrop yield and land use efficiency and the ecological causes of different overyield scenarios. We demonstrate the use of this framework with data from a 128 microplot greenhouse experiment with small annual crops, arranged as seven-species multicrops and their corresponding monocrops, all under two contrasting watering regimes. We applied simple but robust statistical procedures to resulting data (based on bootstrap methods) to compare RMR, and its components, between different plants/plant parts. We also provide simple graphical tools to analyze the data.

 

关键词： agroecosystem sustainability     crop overyielding     intercrop drought resistance     overyield ecological components    

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Taking advantage of drug resistance, a new approach in the war on cancer

null

《医学前沿（英文）》 2018年 第12卷 第4期   页码 490-495 doi: 10.1007/s11684-018-0647-7

摘要：

Identification of the driver mutations in cancer has resulted in the development of a new category of molecularly targeted anti-cancer drugs. However, as was the case with conventional chemotherapies, the effectiveness of these drugs is limited by the emergence of drug-resistant variants. While most cancer therapies are given in combinations that are designed to avoid drug resistance, we discuss here therapeutic approaches that take advantage of the changes in cancer cells that arise upon development of drug resistance. This approach is based on notion that drug resistance comes at a fitness cost to the cancer cell that can be exploited for therapeutic benefit. We discuss the development of sequential drug therapies in which the first therapy is not given with curative intent, but to induce a major new sensitivity that can be targeted with a second drug that selectively targets the acquired vulnerability. This concept of collateral sensitivity has hitherto not been used on a large scale in the clinic and holds great promise for future cancer therapy.

关键词： cancer     drug resistance     genetic screens     senescence     targeted therapy    

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Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

《医学前沿（英文）》 2007年 第1卷 第1期   页码 54-57 doi: 10.1007/s11684-007-0011-9

摘要： The objective of this paper is to explore the value of bone alkaline phosphatase (BALP) for diagnosing osteosarcoma, evaluating the effect of the chemotherapy, judging the prognosis and supervising the relapse and metastasis. The immunoassay was used to check the BALP of the blood serum that was from 42 primary osteosarcoma patients. Alkaline phosphatase (ALP) in blood serum was checked with auto biochemistry equipment. The biopsy tissue and the lesion resected in operation were treated with pathology and histological response was counted. The patients were followed up from five months to 49 months with an average of 24.3 months. Eighteen cases relapsed and transferred, among which, 16 of them were dead, and others were survival to the end of the follow-up. BALP was more sensitive than ALP in diagnosing osteosarcoma ( = 0.015). Fifteen cases decreased to normal value in ALP after preoperative chemotherapy, and 34 cases decreased in BALP. Both ALP and BALP in all cases decreased to normal value in postoperative. There was significant difference in positive correlation between the decrease of BALP and the increase of histological response ( = 0.001, = 0.642). In the followup, there was significant difference in BALP between the group of relapse and transfer and the group of free disease survival ( = 0.000). As a check marker in blood serum, BALP, reflecting the process of ossification, has a higher sensitivity than ALP. It has applied value in the diagnosis of osteosarcoma, reflection of the effect of chemotherapy and forecast the prognosis.
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Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

《医学前沿（英文）》 2007年 第1卷 第3期   页码 274-278 doi: 10.1007/s11684-007-0052-0

摘要： The relative risk (RR) of stroke in patients with hypertension was evaluated by using synthetic index of cerebrovascular hemodynamics. A total of 7,371 patients with hypertension with ages ≥40 years were selected from a population-based cohort study of the risk factors for stroke. The data on the baseline investigation of risk factors, the determination of cerebrovascular hemodynamic parameters (CVHP), and stroke follow-up were analyzed. The RR of stroke in patients with hypertension was evaluated by CVHP scores. Univariate analysis indicated that hypertension, complicated by other risk factors, had significant statistical association with the onset of stroke. RRs for stroke when hypertension complicated with decrease of hemodynamic scores, heart disease, cigarette smoking and alcohol consumption were 4.93 (95%CI, 3.26–7.45), 1.90 (95%CI, 1.36–2.66), 1.99 (95%CI, 1.42–2.79) and 1.73 (95%CI, 1.19–2.53) respectively. In multivariate analysis, hemodynamic score, age, sex, cigarette smoking, family history of stroke and systolic blood pressure were selected by the Cox regression for inclusion in the final analysis. Among them, the RR of hemodynamic score was highest. The analysis of doseresponse relationships indicated that when the hemodynamic scores in patients with hypertension were lower than 75 points, the RR of stroke at 75, 60, 45, 30 and 15 points were 2.85, 4.43, 4.54, 5.40 and 9.88, respectively. The risk of stroke in patients with hypertension is closely asso ciated with hemodynamic impairment and the hemodynamic score may be used for quantitative evaluation of relative risks of stroke.

关键词： inclusion     quantitative evaluation     cerebrovascular     relative     decrease    

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palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

《环境科学与工程前沿（英文）》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1206-4

摘要： • Pd nanoparticles could be reduced and supported by activated sludge microbes. • The effect of biomass on Pd adsorption by microbes is greater than Pd reduction. • More biomass reduces Pd particle size, which is more dispersed on the cell surface. • When the biomass/Pd add to 6, the catalytic reduction rate of Cr(VI) reaches stable. Palladium, a kind of platinum group metal, owns catalytic capacity for a variety of hydrogenations. In this study, Pd nanoparticles (PdNPs) were generated through enzymatic recovery by microbes of activated sludge at various biomass/Pd, and further used for the Cr(VI) reduction. The results show that biomass had a strong adsorption capacity for Pd(II), which was 17.25 mg Pd/g sludge. The XRD and TEM-EDX results confirmed the existence of PdNPs associated with microbes (bio-Pd). The increase of biomass had little effect on the reduction rate of Pd(II), but it could cause decreasing particle size and shifting location of Pd(0) with the better dispersion degree on the cell surface. In the Cr(VI) reduction experiments, Cr(VI) was first adsorbed on bio-Pd with hydrogen and then reduced using active hydrogen as electron donor. Biomass improved the catalytic activity of PdNPs. When the biomass/Pd (w/w) ratio increased to six or higher, Cr(VI) reduction achieved maximum rate that 50 mg/L of Cr(VI) could be rapidly reduced in one minute.

关键词： Palladium nanoparticles     Activated sludge     Hexavalent chromium    

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Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 357-362 doi: 10.1007/s11684-009-0046-1

摘要： The purpose of this study was to investigate the expression of pituitary tumor transforming gene (PTTG) and basic fibroblast growth factor (bFGF) in oral squamous cell carcinoma (OSCC) and tongue cancer cell line Tca8113, as well as their effects on each other. We detected PTTG protein and bFGF in OSCC tissues from 56 cases using the streptavidin-biotin peroxidase (S-P) method; additionally, after being treated with different concentrations of anti bFGF or PTTG antibody, PTTG or bFGF expression in Tca8113 was examined by immunocytochemistry. The results were as follows: (1) Positive rates of PTTG protein and bFGF were 78.2% and 67.3% in OSCC, respectively, which were significantly higher than those in normal mucosal tissues (<0.05). PTTG protein was significantly up-regulated in poorly and moderately differentiated tumors compared to well differentiated tumors (<0.05), and there was also a significant difference between tumors with lymph node metastasis and tumors without lymph node metastasis (<0.05). PTTG protein expression was positively correlated with bFGF ( = 0.382, <0.05); (2) PTTG protein emitted strong fluorescence in Tca8113, and it decreased after being treated with anti-bFGF antibody. Anti-PTTG antibody also had an inhibitive effect on bFGF expression. In summary, the overexpression of PTTG protein is closely related with OSCC differentiation and lymph node metastasis. PTTG protein expression conforms to bFGF in OSCC tissues and Tca8113 cells. Detection of both PTTG and bFGF may help to judge the degree of malignancy and prognosis of patients with OSCC.

关键词： carcinoma     squamous cell     pituitary tumor transforming gene (PTTG) protein     basic fibroblast growth factor    

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Iteration framework for solving mixed lubrication computation problems

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 635-648 doi: 10.1007/s11465-021-0632-8

摘要： The general discrete scheme of time-varying Reynolds equation loses the information of the previous step, which makes it unreasonable. A discretization formula of the Reynolds equation, which is based on the Crank–Nicolson method, is proposed considering the physical message of the previous step. Gauss–Seidel relaxation and distribution relaxation are adopted for the linear operators of pressure during the numerical solution procedure. In addition to the convergent criteria of pressure distribution and load, an estimation framework is developed to investigate the relative error of the most important term in the Reynolds equation. Smooth surface with full contacts and mixed elastohydrodynamic lubrication is tested for validation. The asperity contact and sinusoidal wavy surface are examined by the proposed discrete scheme. Results show the precipitous decline in the boundary of the contact area. The relative error suggests that the pressure distribution is reliable and reflects the accuracy and effectiveness of the developed method.

关键词： mixed lubrication     discretization formula     relative error     Reynolds equation     asperity    

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Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on

GUO Ting, BAI Zhipeng, WU Can, ZHU Tan

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 224-229 doi: 10.1007/s11783-008-0039-3

摘要： TiO supported on active carbon fiber (TiO/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO/ACF were studied, and then, the purification capability of TiO/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH = 30% is the optimal condition for purifying toluene in our experimental system.

关键词： application     gas-solid adsorption     technique     TiO/ACF     experimental    

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大相对口径大线视场光学系统的设计

潘君骅

《中国工程科学》 2000年 第2卷 第8期   页码 89-90

摘要：

文章论述了用于红外远距离探测的光学应是全反射式的大相对口径、大视场的离轴非球面系统。给出了一个通光口径为Φ600mm，相对口径1:1.67，线视场为±5°的设计结果。

关键词： 红外探测     相对口径     大视场     离轴系统     非球面    

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An autonomous miniature wheeled robot based on visual feedback control

CHEN Haichu

《机械工程前沿（英文）》 2007年 第2卷 第2期   页码 197-200 doi: 10.1007/s11465-007-0033-7

摘要： Using two micro-motors, a novel omni-direction miniature wheeled robot is designed on the basis of the bi-corner driving principle. The robot takes advantage of the Bluetooth technology to wirelessly transmit data at a short distance. Its position and omni-direction motion are precise. A Charge Coupled Device (CCD) camera is used for measuring and for visual navi gation. A control system is developed. The precision of the position is 0.5 mm, the resolution is about 0.05 mm, and the maximum velocity is about 52 mm/s. The visual navigation and control system allow the robot to navigate and track the target and to accomplish autonomous locomotion.

关键词： measuring     distance     autonomous locomotion     advantage     navigation    

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LYX: A novel aerobic bacterium with advantage of removing nitrate high effectively by assimilation and

Yuxin Li, Jiayin Ling, Pengcheng Chen, Jinliang Chen, Ruizhi Dai, Jinsong Liao, Jiejing Yu, Yanbin Xu

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1349-3

摘要： Abstract • Pseudomonas mendocina was first reported for aerobic nitrate removal. • It removed 90% of NO3−-N in 24 h under aerobic conditions. • This strain converted NO3−-N to bio-nitrogen (37.9%) and gaseous nitrogen (49.7%). • Inoculation of this strain increased sludge denitrification rate by 4.3 times. The problem of nitrate accumulation in aerobic tank and total nitrogen excessive discharge in effluent was very common in traditional livestock and poultry farming wastewater treatment systems owing to the lengthy process flow and low process control level. A strain LYX of aerobic bacterium was isolated from the activated sludge of a wastewater treatment system in a pig farm, which could remove nitrate effectively in aerobic tank and was identified Pseudomonas mendocina by 16S rRNA sequencing. Under the condition of nitrate as the sole nitrogen source, this strain removed over 90% of NO3−-N with an initial concentration of 110 mg/L under aerobic conditions within 48 hours. Among them, 37.9% of NO3−-N was assimilated into Bio-N, about 51.9% was reduced to gaseous nitrogen and less than 0.5% of nitrogen was replaced by NO2−-N and NH4+-N, 9.7% NO3−-N remained in the effluent at the end. At the same time, four key genes (napA, nirK, norB and nosZ) related to nitrate nitrogen removal were expressed during the denitrification process of P. mendocina LYX, in which the transcription level of the indicator genes of this aerobic denitrifying bacterium (napA) was the highest. In addition, it was found with the 15N tracer technique that inoculation of this strain on sludge increased the amount of nitrogen loss from 9.26 nmol N/(g·h) to 23.835 nmol N/(g·h). Therefore, P. medocina LYX is a potential bioagent for advanced nitrogen removal by assimilating and reducing nitrate simultaneously in aerobic tanks.

关键词： Pseudomonas mendocina     Aerobic nitrate removal     15N tracing technique     Denitrification assimilatively and disimilatively     Aerobic denitrifying genes    

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Modeling of coal swelling induced by water vapor adsorption

Zhejun PAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 94-103 doi: 10.1007/s11705-011-1172-2

摘要： Gas adsorption-induced coal swelling is a well-know phenomenon. Coal swelling or shrinkage by adsorption or desorption of water vapor has not been well understood but has significant implications on gas drainage process for underground coal mining and for primary and enhanced coalbed methane production. Decreased matrix moisture content leads to coal shrinkage and thus the change of cleat porosity and permeability under reservoir conditions. Unlike gas adsorption in coal which usually forms a single layer of adsorbed molecules, water vapor adsorption in the coal micropores forms multilayer of adsorbed molecules. In this work, a model has been developed to describe the coal swelling strain with respect to the amount of moisture intake by the coal matrix. The model extended an energy balance approach for gas adsorption-induced coal swelling to water vapor adsorption-induced coal swelling, assuming that only the first layer of adsorbed molecules of the multilayer adsorption changes the surface energy, which thus causes coal to swell. The model is applied to describe the experimental swelling strain data measured on an Australian coal. The results show good agreement between the model and the experimental data.

关键词： multilayer adsorption     vapour pressure     coal shrinkage     relative humidity     permeability    

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Mechanical and geometric advantages in compliant mechanism optimization

Michael Yu WANG

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 229-241 doi: 10.1007/s11465-009-0066-1

摘要： This paper presents a focused examination of the mechanical and geometric advantages in compliant mechanisms and their ramifications in the design formulations of compliant mechanisms posed as a topology optimization problem. With a linear elastic structural analysis, we quantify mechanical (and geometric) advantage in terms of the stiffness elements of the mechanism's structure. We then analyze the common formulations of compliant mechanism optimization and the role of the external springs added in the formulations. It is shown that the common formulations using mechanical (or geometric) advantage would directly emulate at best a rigid-body linkage to the true optimum design. As a result, the topology optimization generates point flexures in the resulting optimal mechanisms. A case study is investigated to demonstrate the resulting trends in the current formulations.

关键词： compliant mechanisms     topology optimization     mechanical advantage     pseudo rigid-body mechanisms    

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Analysis of stress and failure in rock specimens with closed and open flaws on the surface

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1222-1237 doi: 10.1007/s11709-021-0773-1

摘要： The influence of closed and open surface flaws on the stress distribution and failure in rock specimens is investigated. Heterogeneous finite element models are developed to simulate the compression tests on flawed rock specimens. The simulated specimens include those with closed flaws and those with open flaws on the surface. Systematic analyses are conducted to investigate the influences of the flaw inclination, friction coefficient and the confining stress on failure behavior. Numerical results show significant differences in the stress, displacement, and failure behavior of the closed and open flaws when they are subjected to pure compression; however, their behaviors under shear and tensile loads are similar. According to the results, when compression is the dominant mode of stress applied to the flaw surface, an open flaw may play a destressing role in the rock and relocate the stress concentration and failure zones. The presented results in this article suggest that failure at the rock surface may be managed in a favorable manner by fabricating open flaws on the rock surface. The insights gained from this research can be helpful in managing failure at the boundaries of rock structures.

关键词： surface flaw     heterogeneity     circular hole     numerical modeling     relative displacement    

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标题 作者 时间 类型 操作

EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

期刊论文

HOW MULTISPECIES INTERCROP ADVANTAGE RESPONDS TO WATER STRESS: A YIELD-COMPONENT ECOLOGICAL FRAMEWORK

期刊论文

Taking advantage of drug resistance, a new approach in the war on cancer

null

期刊论文

Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

期刊论文

Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

期刊论文

palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

期刊论文

Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

期刊论文

Iteration framework for solving mixed lubrication computation problems

期刊论文

Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on

GUO Ting, BAI Zhipeng, WU Can, ZHU Tan

期刊论文

大相对口径大线视场光学系统的设计

潘君骅

期刊论文

An autonomous miniature wheeled robot based on visual feedback control

CHEN Haichu

期刊论文

LYX: A novel aerobic bacterium with advantage of removing nitrate high effectively by assimilation and

Yuxin Li, Jiayin Ling, Pengcheng Chen, Jinliang Chen, Ruizhi Dai, Jinsong Liao, Jiejing Yu, Yanbin Xu

期刊论文

Modeling of coal swelling induced by water vapor adsorption

Zhejun PAN

期刊论文

Mechanical and geometric advantages in compliant mechanism optimization

Michael Yu WANG

期刊论文

Analysis of stress and failure in rock specimens with closed and open flaws on the surface

期刊论文