酶箱模具设计和改讲

通过对酶箱模具设计和改进过程的分析,提出了企业在追求低投入高产出时,必须是在确保产品质量的前提下考虑效益最大化,否则是得不偿失的。提示设计人员在搞设计时,要把握住质量和投入的平衡。     

Convergence of the IRWLS Procedure to the Support Vector Machine Solution

An iterative reweighted least squares (IRWLS) procedure recently proposed is shown to converge to the support vector machine solution. The convergence to a stationary point is ensured by modifying the original IRWLS procedure.     

Difficulties in the approval of clinical trials in Spain. An obstacle race]

The purpose of this study is to observe the disease-disability association through a cross-sectional study. Between 1994 and 1995, we conducted a questionnaire survey in 5 towns in Japan. Among the items included in the questionnaire, 5 related to ADL (bathing, feeding, dressing/undressing, toileting, and going out socially) were treated as purpose variables; and 5 related to the history of medical treatment received over the past year (diabetes, heart disease, cerebrovascular disease, neuralgia, and bone fractures) were used as explanatory variables. Multiple logistic models were applied to observe the relationship. The history of medical treatment for cerebrovascular disease greatly and unavoidably affects disability related to ADL. Bone fractures, diabetes, and heart diseases contributed to specific ADL disabilities.     

服装市场调查的若干误区及改进

基于应用统计学知识及市场调研文献资料,通过对服装市场调研方法、工具以及问卷调研的评价指标梳理,结合服装市场问卷调研的实际案例和常见问题及误区,探析产生原因及改进方法,为从事相关工作的调查者提供借鉴。     

上海浦东新区屋顶绿化建设要素分析

在对上海市浦东新区屋顶绿化现状系统调查的基础上,从建筑基础、屋面类型、功能定位、建设面积、绿化方式、植物应用等方面,对屋顶绿化建设要素进行系统分类和分析.分析了屋顶绿化各个建设因子的特征,比较各个因子的异同点和相互联系,讨论屋顶绿化与建筑的相互关系,分析屋顶绿化建设模式,提出屋顶绿化建设的整合分析以及屋顶绿化建设的认同性和定位性,总结屋顶绿化建设的适宜途径,为屋顶绿化发展提供借鉴和参考.     

A combined analysis of backward trajectories and aerosol chemistry to characterise long-range transport episodes of particulate matter: the Madrid air basin, a case study

This study has investigated the influence of synoptic weather patterns and long-range transport episodes on the concentration levels of airborne particulate matter (TSP, PM10 and PM2.5) and some major ions (SO(4)(2-), NO(3)(-) and NH(4)(+)) at a background rural station in central Spain. Air mass back-trajectories arriving at the site in 1999-2005 have been analysed by statistical methods. First, cluster analysis was used to group trajectories into 8 clusters depending on their direction and speed. Meteorological scenarios associated to each cluster have been obtained and interpreted. Then, the incidence of different air mass transport patterns on particle concentrations and composition recorded at this station was evaluated. This evaluation included PM10 and PM2.5 concentrations and chemical composition data, obtained at three representative sites of the Madrid air basin during sampling campaigns carried out in the course of the 1999-2005 period. Finally, a residence time analysis of trajectories was also performed to detect remote sources and transport pathways. Significantly elevated concentrations of TSP and PM10 were observed for Northern African flows as a consequence of the transport of mineral dust. Significant inter-cluster differences were also observed for PM2.5 and secondary inorganic compounds, with the highest concentrations associated with low baric gradient situations and Southern European flows. The residence time analysis confirmed that current TSP and PM10 concentrations in central Spain are likely to be influenced significantly by long-range transport of desert dust from different desert regions in North Africa. Furthermore, emissions from continental Europe with a high time of residence in the western and central areas of the Mediterranean basin, seem to significantly influence PM2.5 and secondary inorganic aerosol concentrations in this region.     

Extending the shelf life of kohlrabi stems by modified atmosphere packaging

ABSTRACT:  Kohlrabi stems (without leaves) were stored under modified atmosphere packaging (MAP) for 60 d at 0 °C. An additional retail sale period of 3 d at 12 °C after each cold storage evaluation (30 and 60 d) was applied. Under high relative humidity (RH) and 0 °C, the stems showed low metabolic activity, as no changes in sugars and organic acids were found. From day 21 at 0 °C, air-stored stems showed a yellowing of stalks and later they fell down. This disorder severely affected the appearance of stems. A gas composition of 4.5 to 5.5 kPa O₂ plus 11 to 12 kPa CO₂ was reached using antimist oriented polypropylene plastic bags of 20-μm thicknesses. The stems in MAP conditions kept a high sensorial quality. It was enough for commercial purpose of 2 mo. The storage of kohlrabi stems in plastic bags, either MA or in perforated (control) packages, provided an additional protection reducing physical damage. The MAP conditions delayed the weight loss and development of bacterial soft and black rot, extending the shelf life of kohlrabi stems to 60 d at 0 °C plus 3 d at 12 °C. Stems are not chilling injury sensitive.     

Quality of cauliflower as influenced by film wrapping during shipment

 Throughout the season, 'Siria' cauliflower heads from three harvesting periods were film-wrapped and stored for 1 week at 1.5  °C to simulate a maximum period of commercial shipment. After cold storage, the heads were kept for 2.5 days at 20  °C to simulate a retail sale period. Different polymeric films – polyvinyl chloride (PVC) of 14 μm thickness, low-density polyethylene (LDPE) of 11, 15 and 20 μm thicknesses and a special LDPE of 11 μm thickness adapted for microwave ovenuse – were used for wrapping. Soluble solid content, pH, titratable acidity, weight loss, physiological disorders, fungal attacks, visual quality and gas composition within packages were monitored. After the shelf life simulation, among the LDPE films studied, the best results were obtained by using 11 μm LDPE. Gas composition (about 16% O₂ and 2% CO₂ during cold storage, and about 11% O₂ and 3.5% CO₂ during retail sale simulation), overall quality, yellowing and browning of the head, and Alternaria spp. development were at similar levels among the films studied. However, weight loss was considerably lower for all LDPE films than for PVC film. For commercial purposes 11 μm LDPE could be a good alternative to PVC for wrapping cauliflower. Received: 30 October 1998 / Revised version: 18 January 1999     

Browning susceptibility of minimally processed Baby and Romaine lettuces

 This study was conducted to determine the effects of cultivar, tissue susceptibility and storage temperature on the keeping quality of minimally processed Baby and Romaine lettuces. Midrib and photosynthetic tissues were lightly processed and stored for up to 7 days at 5  °C and 13  °C. Changes in L ^* and a ^* values and absorbance at 430 nm were compared. The relationship between polyphenols, phenylalanine ammonia lyase (PAL) and polyphenol oxidase (PPO) activities and browning was examined. Measurements of L ^* and a ^* values on midribs showed that browning discoloration was the same for Baby as for Romaine lettuces and there was no relationship for temperature. In addition, L ^* and a ^* values in photosynthetic tissue indicated a decrease in green pigmentation during storage, especially at 13  °C. For both kinds of tissue at the end of cold storage an increase in soluble brown polymers was detected. In midribs, total phenolics increased significantly throughout the storage period because of the tissue-wounding response. The photosynthetic tissue had a higher phenolic content than the midrib one. For both kinds of tissue an increase in PPO activity occurred throughout cold storage. On the other hand, PAL activity in midrib tissue only increased initially, followed by a slow decline to reach normal levels. Browning potential estimated by L ^* values correlated significantly (P>95%) with PPO activity and with absorbance at 430 nm for Romaine lettuce. Based on colour and browning potential no differences between Romaine and Baby lettuce cultivars were observed. However, photosynthetic tissue was the most suitable tissue for the preparation of minimally processed salad mixes because of its high phenolic content. Received: 28 September 1998