表面增强拉曼试纸的制备及保质性

以滤纸的多级纤维结构为基底,通过物理气相沉积(PVD)方法蒸镀一定厚度的银膜,制备了表面增强拉曼试纸,以罗丹明6G(R6G)为探针分子,其最低检测限(LOD)可以达到10-10mol/L.采用密闭氮气环境保存可解决银SERS基底使用寿命短的问题,使得试纸可以长时间保持活性.

Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves

[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following： water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical.

Study on Present Status of Plant Germplasm Resources Conservation and Countermeasures

Plant germplasm resources is the material foundation and key point for agricultural production, crop breeding and bioengineering. China is one of the centers for the origin of the cultivated plants worldwide, as well as one of the countries with most abundant plant resources and the highest biodiversity. Strengthening research in the conservation and utilization of plant germplasm resources is of significant value and importance. In this study, the present status of conservation, utilization, and existing problems of plant germplasm resources in China and around the world were reviewed; further, through analyzing measures taken by global countries for plant germplasm resources protection, countermeasures for plant germplasm resources conservation in China were also presented from three aspects, namely, collection and conservation, information network construction and national legislation and policies.

Analysis of Application of Superabsorbent Polymer in Sandy Soils

[Objective]The aim was to research water retention of superabsorbent polymer （SAP） in sandy soils. [Method] With soils from an ancient course in the Yel ow River as materials, acrylate SAP was taken as water retention materials to conduct the test. [Result] With 0.2%-0.4% SAP added, dewatering period of sandy soil extended after irrigation; the period of water retention quantity over 10% last for 42 d, which was significantly more than that of the control group in 16 d （saturated water reducing to 10%）; water retention effect proved better at the 2nd irrigation without soil stirring compared with the 1st irrigation. [Conclusion] The mixture of SAP with sandy soils promotes water retention in soils.

Primary Identification of Alien Chromatin in T911289,a Maintainer of Wheat Male Sterile Line with Cytoplasm of Aegilops kotschyi

The genomic composition of 1911289, a wheat ( Tritium aestivum L.) maintainer of K-CMS, was examined by several methods, such as genomic in situ hybridization (GISH), biochemical marking, and DNA molecular marking. The results got by GISH and PCR amplification of dispersed rye-specific repetitive DNA sequence suggested that the alien chromatin in T911289 derived from rye. Specifically PCR amplification of the rye-specific microsatellite primers (SCM9) and seed storage protein analysis indicated that the alien chromatin in T911289 had developed from the short arm of 1R chromosome of rye (1RS). PCR amplification by using microsatellite primers locating on 1BS and seed storage protein analysis also revealed that 1911289 had lost the arm of 1BS or a small distal segment of it. We conclude that T911289 is a heterogeneous population which displays two distinct different types of translocation, i.e. the Robertsonian translocation and small segment translocation. The Robertsonian translocation type observed in our study is different from the 1BL/1RS translocation which is widely used in wheat production; it may be a novel and complex translocation form. Though the linkage between the desirable agronomic traits and the deleterious genes expressed as sticky dough has not got broken in T911289, the recovery of small segment translocation will still benefit the genetic study of wheat and rye.

Comparison of Genetic Diversity Between Local Cultivated Aromatic and Non-aromatic Rice in Yunnan Province

[ Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice. [Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [ Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice, respectively. Average genetic multiplicity index（Hs） was 0.46 and 0.67 respectively. The average polymorphism information content （PIC） was 0.43 and 0.58 in aromatic and non-aromatic rice respectively. [ Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice.

Progress on Light-controlled Preservation Technology of Postharvest Vegetables

Preservation technology of light control has received the widespread atten- tion for its safety, green, environmental-protection, high efficiency. It has become the hotspot in the area of postharvest vegetables preservation. It could mainly be divid- ed into three categories： LED preservation, UV preservation and radiation preserva- tion. This paper systematically reviewed the mechanisms of different preservation technology of light control, summarized the research progress of light-controlled tech- nology in the physiological characteristics regulation, maintenance of nutritional quali- ty and microbial control of postharvest vegetables at home and aborad, and prospected the further studies on preservation technology for postharvest vegetables.

Mei Symmetry and Conserved Ouantity of Tzénoff Equations for Nonholonomic Systems of Non-Chetaev's Type

Mei symmetry of Tzenoff equations for nonholonomic systems of non-Chetaev＇s type under the infinitesimal transformations of groups is studied. Its definitions and discriminant equations of Mei symmetry are given. Sufficient and necessary condition of Lie symmetry deduced by the Mei symmetry is also given. Hojman conserved quantity of Tzenoff equations for the systems through Lie symmetry in the condition of special Mei symmetry is obtained.

Recent Advances in Researches on Physiologically Active Substances in Holothurians

In this report, we reviewed recent literature on physiologically active substances from sea cucumbers (SCs) andtheir activities together with results obtained from our study. Preventive properties against lipid metabolism were reported inrats using a whole SC preparation with no particular constituent specified. Administration of the preparation lowered serumand hepatic cholesterol levels and improved the HDL/LDL ratio. These functions may be attributed to the stimulatory effectof the extract on the secretion of cholesterol in feces. Novel fucosylated chondroitin sulfates (FCSs) from Ludwigothureagrisea significantly induced fibroblast growth factor 2-dependent angiogenesis in human umbilical vein endothelial cells (HU-VECs). The proangiogenetic activity seemed attributable to the action of the sulfated fucose branches on the polysaccharide.SCs contain mycosporine-like amino acids (MAAs) that are capable of absorbing UV. A biogenetic precursor of MAAs wasfirst reported in SCs. The anti-proliferative effects of a branched chain fatty acid from a sea cucumber on prostate cancercells was reported with the activity of 5-lipoxygenase. Glycosphingolipid constituents in SCs have been systematically ana-lyzed over the past ten years. The results showed that the gangliosides in several SCs differed from those of mammals in thata sialic acid of SC gangliosides directly binded to glucose of cerebroside. Neuritogenic activity of the glycosphingolipids wasdemonstrated in vitro experiments and may lead to the development of therapeutic products for neurological disorders. Ourstudy also showed that sphingoid bases, the hydrolyzed products of glycosphingolipids from SCs, induced significant apoptosisin several tumor cell lines.

IMPROVING ELEVATOR MAINTENANCE PERFORMANCE: WORK STUDY APPROACH

Strategic quality management is implemented in a local elevator company. Quality strategies, policies and goals focusing on customers′ needs are clearly established. Continuous quality improvement has been adopted as the corporate strategy to improve its performance and competitive edge. This paper presents the successful implementation of a quality improvement project using the work study approach. On the completion of the project, the rate of serious defects which may lead to an accident is reduced by 55%, i.e., from 2%￣0.9% over a period of two years. A total of HK$ 1.1 million spent on the project is justified when compared with the reduction of financial risks involved. The success of the project demonstrates that the work study approach could be an effective tool for improving the performance of maintenance work.

A Preliminary Study on the Calculating Method for the Evolution of Siltation and Erosion of Tidal Flat Based on GIS

T he estuary and coast is an area where the land and the sea interact and a place in which human beings frequently move about so that understanding and controlling the change and development modes of the coastal landform plays a vital part in exploiting and protecting coastal resources. A model is the generalization and abstraction of objective things. This paper summarizes four methods for the landform development of the tidal shore and underwater delta, mainly discusses the model’s structural elements, and presents their specific application on the basis of the authors’ case study. With the application of the profile model, the dynamic change of coastal landform can be clearly seen by contrasting the different profiles of different years. Through the shrinking, expanding and transformation of the isobath, plane model is used to study the macro-change of the shoal and the coastal landform. Speed model is an efficient means to analyze the trend of erosion and deposition and the local change in a great area of the sea. Statistical survey model is a static analysis, which can be used to establish the relationship between the erosion and deposition of the shoal and the altitude and slope of survey spot.

THE RHEOLOGICAL PROPERTIES AND OUTBURST MECHANISM OF GASEOUS COAL

Coal and methane outburst is one of the harmful disasters in coal mines. We have studied the rheological properties of gaseous coal in laboratory and obtained its rheological fracture principle. This principle can better explain and describe the outburst mechanism of gaseous coal. Thereby a rheological hypothesis of coal and methane outburst is put forward in this paper.

Quantum Properties of Two-Mode Squeezed Even and Odd Coherent States

Two new types of quantum states are constructed by applying the operator s（ξ） = exp（ξ＊ ab - ξa＋b＋） on the two-mode even and odd coherent states. The mathematical and quantum statistical properties of such states are investigated. Various nonclassical features of these states, such as squeezing properties, the inter-mode photon bunching, and the violation of Cauchy-Schwarz inequality, are discussed. The Wigner function in these states are studied in detail.

A customized extended warranty policy with heterogeneous usage rate and purchasing date

To increase customers'satisfaction and promote product's competitiveness,a customized extended warranty(EW)policy is proposed,where the diversities in both the usage rate and purchase date are considered.The marginal approach is applied to describe the product's two-dimensional failure in terms of age and usage,respectively.Moreover,minimal repair is adopted to restore the failure,and the virtual age method is applied to depict the effect of preventive maintenance(PM).On this basis,an optimization model is established to minimize the maintenance cost and warranty cost from the manufacturer's view,and multiple factors are taken into account,including the PM's intensity and its period,and EW's interval,etc.A numerical case study is provided to illustrate the effectiveness of the proposed approach.The results show that by considering the product's usage rate and the purchasing date of EW,the number of failures as well as the cost of maintenance and warranty can be reduced effectively.

Evaluation of Infiltration Capacity and Water Retention Potential of Amended Soil Using Bamboo Charcoal and Humus for Urban Flood Prevention

In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whole basin. There are several basic technologies for river basin management, such as infiltration trenches or rainwater storage. However, a method of soil amendment that prevents flood disasters has not been established. This study aims to evaluate the infiltration capacity of soil amendments using bamboo charcoal and humus. A constant-head infiltration test and rainfall simulation were conducted to evaluate the properties of the soil amendments. The constant-head infiltration test＇s results showed that soils mixed with 30% humus had the greatest potential for influencing initial and final infiltration rates, and the more the mixing rates of bamboo charcoal and humus were increased, the higher the water retention capacity. The results of the rainfall simulation showed that soils mixed with 30% humus had the highest final infiltration rates and lowest multiplication spillage. To reduce the runoff volume using soil amendment technology, it is important to delay overland flow, and the hydraulic properties of the soils mixed with bamboo charcoal and humus were as effective as those of granite soils.

The new economy of nature:can carbon pay for nature conservation? The case of the Hong Kong Country Parks

The Country Parks of Hong Kong occupy 40%of the total landmass of Hong Kong,and consists of vast areas of secondary woodlands,scrublands,grasslands,and reservoirs.That vegetation-and the soil underneathsubtract carbon from the atmosphere,which has a market value.The aim of this paper is to estimate the value of that carbon,to assess whether that value would be sufficient to pay for the upkeep of the Country Parks,and to compare that value to the costs of alternative ways to reduce atmospheric carbon dioxide.To do this,we compare the land cover of 1978,1991,1997 and 2004 using remote sensing,and identify the three predominant land covers(woodlands,scrublands,grasslands) .We then estimate the amount and value of the carbon sequestered by the vegetation and soil of the Country Parks,and compare it to the budget available to the Agriculture,Fisheries and Conservation Department to run the Country Parks(HK$234 million in 2009/2010) .We extrapolate our results over 50 years,from 1978 to 2028.We conclude that by 2028 the carbon sequestered would be valued over HK$800 million,but the value of the additional carbon subtracted yearly would only cover approximately 7%of the total budget needed to run the Country Parks.We also conclude that because of the large budget allocated to the Country Parks,alternative methods of carbon sequestration-represented by the EU ETS price of carbon-are much cheaper.

Effect of lead on ERK activity and the protective function of bFGF in rat primary culture astroglia

Objective： To observe the effects of lead on levels ofphosphorylated extracellular signal regulated kinase （p-ERK） in the cytoplasm of primary cultures of rat astroglial cells and the possible protective effect of basic fibroblast growth factor （bFGF） on lead-induced effects. Methods： The primary astroglia cells from 1-6 d old Wistar rats were cultured. The cells pretreated with the MEK1 （mitogen-activated protein kinase kinase 1） inhibitor PD98059 and bFGF, respectively, were exposed to Pb acetate of different concentrations for different times. Western blotting and reverse transcription polymerase chain reaction （RT-PCR） methods were used to detect the protein and mRNA expressions of ERK. Results： mRNA expression for ERK peaked 15 min after initiation of lead exposure （P〈0.05） and protein expression of p-ERK peaked at 30 min （P〈0.05）. ERK mRNA levels and p-ERK protein levels returned to baseline after 60 and 120 min of lead exposure, respectively （P〉0.05）. The increase in p-ERK levels in lead-treated cells could be inhibited by PD098059. Activation of ERK in the cells by lead was prevented by pretreatment with bFGF. Total ERK protein levels did not change under the same experimental conditions （P〉0.05）. Conclusion： Low-level lead exposure resulted in transient activation of ERK through the MEK pathway, which then returned to basal levels in the continued presence of lead. Exogenous bFGF protected ERK signaling components in astroglia from lead poisoning.

Microbial Aspects in Comparing Modified Atmosphere Packaging and Vacuum Packaging on Shelf Life of Fresh Bull Meat

The importance of meat preservation and various reports on different types of packaging, and to compare the effects of modified atmosphere packaging （MAP） and vacuum packaging （VP） on shelf life of flesh bull meat, and microbiological tests on meat together with some chemical and sensory tests was on tight observation. It was an experimental study, 96 samples were randomly packaged in two groups of MAP and VP equally. The package consists of five layers which are Polyvinylidin Chloride （PVDC）, Ethyl Vinyl Alcohol （EVOH）, Poly Ethylene （PE）, Linear Low Density Poly Ethylene （LLDPE）, and poly Amid （PA）, respectively. MAP meat with 700 mL of CO2 per kg of meat. The packaging were made in at-ameh-pars factory and transported in chilled condition to a well prepared refrigerator in National Research Institute of Food Science （NRIFS） of Shahidbeheshti University of Medical Sciences. These samples tested weekly, since first day after packaging, and week 2, 3, 4, 5, 6, 7, and 8. Microbial tests include Total Microbial, Coliform, Lactic Acid Bacteria, Pseudomonas Counts, and Clostridium. Chemical and sensory tests also carried out. Total volatile bases （TVN）, TBA, and pH as chemical analyses and color, odor, and weep as sensory analyses are also added. Results revealed that total microbial count was in standard range within the 6 weeks for VP, and 5 weeks for MAP technique. Other microbial factors including coliforms, lactic acid bacteria are less and somehow in chemical and sensory tests emphasized the microbial figures. recommended for meat packaging. similar pattern to total count, and no clostridia were found. By the way, The results showed that according to our existing facilities, VP is

Effect of Soil and Water Conservation Measures on Selected Soil Physical and Chemical Properties and Barley （Hordeum spp.） Yield

A study was conducted in 2007/2008 at Absela locality, Banja Shikudad District of the Amhara National Regional State, Ethiopia to evaluate the effects of soil bunds stabilized with vetiver grass （IT. zizanioides） and tree lucerne （C. palmensis） on soil physical and chemical properties, bund height, inter-terrace slope and barley （Hordeum vulgare L.） yield. Data were analyzed using one-way analysis of variance （ANOVA） and mean values for the treatments were separated using Duncan＇s Multiple Range Test. Results indicated that the non-conserved fields had significantly （p 〈 0.05） lower organic carbon and was found to contain 66% less OM from the average of the conserved treatment. 9-year old sole soil bund, the 9-year old soil bund stabilized with tree lucerne, the 9-year old soil bund stabilized with vetiver, and the 6-year old soil bund stabilized with tree lucerne had 71.20, 68.56, 52.30, and 36.12%, respectively higher percent OM than the control treatment. The trend was similar for total nitrogen. The non-conserved treatment had a higher bulk density when compared to the conserved fields. Fields with soil bunds stabilized with vetiver grass had the highest bund height and the lowest inter-terrace slope than fields treated with the rest of remaining conservation measures. Barley grain yields were significantly （P 〈 0.05） greater in both the soil accumulation and loss zones of the conserved fields than the non-conserved （control） treatment. Practicing soil conservation measures and curtailing causes of land degradation could improve the soil physical and chemical properties thereby increase land productivity of the conserved land.

A Simple Bio-preservation Technique to Increase Shelf Life of Ampalavi Mango Fruits Using Aloe vera Gel

Aloe vera is being identified as a potential medicinal plant for its application in industries as well as traditional usage. The gel obtained from the leaves of A. vera has numerous properties. In this study, using the gel to extend the shelf life of Ampalavi mango fruits was studied. Even sized, uniform coloured, matured Ampalavi cultivar mango fruits were surface cleaned and coated with 33%, 66% and 100% gel, respectively. Results revealed that the ripening was delayed due to the coating. The total soluble solid （TSS）, pH and weight loss were high in uncoated fruits. The mean pH of the pulp from fruits kept as control was 4.94 at 4 d fruit preservation period （FPP） and was slightly increased to 5.43 within 12 d FPP, whereas the minimal pH （4.69 at 4 d FPP and 5.03 at 9 d FPP） was noticed in 100% gel coated fruits. The TSS （brix） was significantly in higher levels （13.67°Bx within 4 d FPP and 20.77°Bx within 12 d FPP） in control fruits, whereas the minimum TSS value was 9.27°Bx and 18.03° Bx within 4 d and 12 d FPP, respectively, recorded from the 100% gel coated fruits in storage. The weight loss percentage （WLP） was significantly （P 〈 0.05） higher in control fruits （8.46%）, whereas the lower WLP （1.13%） was found in 100% gel coated fruits after 12 d of storage. This low-scale gel coating technique prolonged the fruits shelf life by delaying the fruit ripening. This effect has to be further investigated to commercialize the natural product for large scale ready-made application.