The sensitivity of a simple root of a polynominal is finite and well defined. For a multiple root, however, the existing definition becomes infinite, even when the root displacements remain finite. In this letter, a well behaved function is proposed to define a multiple-root sensitivity. It is also shown that the new definition, which degenerates to the conventional definition under a special condition, is a meaningful measure of actual root displacements. 相似文献
A novel sanitizer composed of lactic acid and peroxyacetic acid (LA-PAA) was developed as an alternative to chlorinated water (CW) for fresh produce processing. Single strains of Lactobacillus plantarum, nonpathogenic Escherichia coli K-12, and Listeria innocua were used to demonstrate the microbial efficacy of LA-PAA. LA-PAA achieved a >7.8-log reduction of L. innocua and L. plantarum suspended in water at 4°C for 20 s, and LA, PAA, and CW achieved reductions of 0.4, 4.8, and 2.7 log, respectively. LA-PAA, when compared with LA, PAA, and CW, enhanced the reduction of L. innocua attached to romaine leaves by >2.2 log, and improved the removal of E. coli attached to spinach leaves by >2.4 log. The exponential improvement in the microbial efficacy of LA-PAA showed synergism between LA and PAA. LA-PAA microbial efficacy was inversely proportional to pH value and directly correlated with residence time and concentration. Despite an improvement in microbial reduction through the addition of surfactant to LA-PAA, the usage of surfactant in washing fresh produce was impeded by excessive foaming during actual processing. Effects of organic matter on the performance of LA-PAA were minimal. External sensory evaluations showed that LA-PAA had no negative effects on the quality of lettuce and tender leaves. Temperature-abuse studies demonstrated that LA-PAA reduced decay by ~50% when compared with CW. Overall, these results support the premise that LA-PAA has significant potential to be an alternative to CW for fresh produce processing. 相似文献
The effect of preheating on the survival of L. monocytogenes in Richard's broth, which mimics the composition of Camembert cheese composition, was examined. Experiments were carried out to reproduce contamination of cheese with environmental heat-stressed cells of L. monocytogenes surviving hot-cleaning procedures. Cells in mid-log phase were heated for 30 min at 56 degrees C before being inoculated into Richard's broth. The pHs and temperatures of Richard's broth were chosen to recreate the conditions of curd dripping (pH 5, 25 degrees C), of the beginning of cheese ripening (pH 5, 12 degrees C), and of the beginning (pH 5, 4 degrees C) and the end (pH 7, 4 degrees C) of cheese storage. Immediately after heat treatment, the viability loss was especially high for strain 306715, which exhibited only 0.6% +/- 0.2% survival, compared with 22% +/- 8.7% for strain EGD. The percentages of the surviving heated cells that were injured were 93% +/- 8% for strain 306715 and 98% +/- 3% for strain EGD. The destruction of the surviving L. monocytogenes cells was accelerated when they encountered the pH and temperature conditions of Camembert cheese during manufacturing, ripening, and cold storage (pH 5 at 25, 12, and 4 degrees C, respectively). The multiplication of the surviving heated cells was retarded under favorable growth conditions similar to those of storage by the distributor and the consumer (pH 7 at 4 and 12 degrees C, respectively). 相似文献
In this study, new and efficient sorbent with density 0.2 g/cm3 was fabricated by incorporating rice straw into polyurethane matrix to get an open cell structure material with high oil uptake capacity. The influences of various important factors such as amount of adding rice straw, size of rice straw particles, and adsorption time on oil adsorption capacity of new sorbent material were investigated. The results showed that the oil absorption rate occurred fast in first 15–30 min, then slowed down and reached saturation level after about 2 h of treatment. Oil adsorption capacity of the new sorbent material was relatively high, up to 12.0 g/g. In comparison with pristine polyurethane or lignocellulosic materials, the new sorbents had higher oil adsorption capacity. Some characteristics of the as-obtained sorbent, such as surface shapes and porosity, were also studied by SEM analysis. 相似文献
Nonthermal plasma (NTP) is defined in terms of partly ionised gas which overall temperature is quite low because the stored energy is mostly in free electrons. Applications of NTP have been expanded to new areas of food applications such as the microbial inactivation and also the elimination of pesticide and toxic chemical residues in food such as fruits and vegetables while nutritional content and key characteristics are still preserved. Plasma treatment has successfully decreased the concentrations of pesticides by about 45‐71%. In this article, NTP technologies as well as investigations about applying of NTP for removing pesticide residues and improving microbial safety in fresh produce are described. Potential applications of NTP in food processing together with some of their challenges and limitations are also discussed. 相似文献
Stretchable and wearable sensor technology has attracted significant interests and created high technological impact on portable healthcare and smart human–machine interfaces. Wearable electromechanical systems are an important part of this technology that has recently witnessed tremendous progress toward high‐performance devices for commercialization. Over the past few years, great attention has been paid to simultaneously enhance the sensitivity and stretchability of the electromechanical sensors toward high sensitivity, ultra‐stretchability, low power consumption or self‐power functionalities, miniaturisation as well as simplicity in design and fabrication. This work presents state‐of‐the‐art advanced materials and rational designs of electromechanical sensors for wearable applications. Advances in various sensing concepts and structural designs for intrinsic stretchable conductive materials as well as advanced rational platforms are discussed. In addition, the practical applications and challenges in the development of stretchable electromechanical sensors are briefly mentioned and highlighted. 相似文献
Obesity is a serious epidemic health problem that can cause many other diseases including type 2 diabetes and cardiovascular diseases. Current approaches to combat obesity suffer from low effectiveness and adverse side effects. Here, a new self‐administrable and minimally invasive transdermal drug delivery strategy for home‐based long‐term treatment of obesity and other diseases is developed. Specifically, ultrathin, core‐shelled, and lance‐shaped polymeric drug reservoirs (micro‐lances [MLs]) are readily fabricated by a thermal pressing molding method and totally implanted into subcutaneous fat by lancing through the skin. Using a diet‐induced obese mouse model, it is shown that the development of obesity and associated metabolic disorders is effectively inhibited by applying therapeutic core‐shelled MLs once every 2 weeks. The outstanding therapeutic effects are attributable to highly localized and biphasic drug release, as well as combination therapy based on browning transformation of white fat and enhanced insulin sensitivity. 相似文献
Due to the distributed and decentralized nature of social media, respective content that contains misinformation is usually propagated without any type of moderation, which may mislead the public and have a profound real-world impact. In addition, it is quite challenging to distinguish misinformation with high precision, since the content is often short and lacks of semantics. A promising solution is to utilize the crowdsourcing wisdom that pushes the suspected misinformation to relevant users based on the expertise and collects the assessments to judge the credibility. Even though a lot of expert finding models have been employed, however, these methods cannot effectively deal with the misinformation-oriented expert matching tasks since the data collected from social network is different form traditional text collection. To this end, we focus on how to obtain an appropriate matching between the suspect misinformation and corresponding experts, and propose a multi-topic expert finding method, called LTM (List based Topic Model), to sufficiently utilize crowdsourcing wisdom. Moreover, we optimize the query results with the help of supervised information that extracted from Twitter Lists. Finally, we demonstrate the effectiveness of our work with experiments on real-world data and verify the superiority of our proposed model in accuracy.
Yield improvement efforts traditionally involve extensive experimental work aimed at diagnosis of defect sources. This paper proposes a methodology for supplementing such experimental work with defect simulation. In particular, it is shown that lithography defect simulation can provide insight into defect mechanisms that cause major distortions in photoresist profiles. The nature of the distorted patterns can assist us in yield improvement efforts, since by comparing simulation results with the observed photoresist profiles on wafers, defect sources may be identified. Several lithography defect diagnosis examples are presented to demonstrate the approach 相似文献