徜徉花海

早春三月，花花草草从沉睡中醒来，带给我们无限惊喜，在我们的幻想世界中，人们都佩戴着美丽的首饰，其外表能够与毛莨，勿忘我，矢车菊和其它花朵相媲美，黎明，从花朵到露珠润湿的叶片，无不散发着隐藏的魔力。     

MOCVD Growth of Doped GaAs/AlGaAs Quantum Heterostructures

The influences of growth techniques of AP-MOCVD GaAs/AlGaAs silicon-doped multi-quantum wells(MQWs), heterostructure bipolar transistors (HBTs), double barrier resonant tunneling diodes(DBRTDs) ontheir structures and performances were studied. Continuously grown MQWs, that is, no growth interruption atthe heterointerfaces, shown blue-shifted, narrower and stronger photoluminescence(PL) compared withinterruptedly grown ones.TEM examination of the interrupted interfaces revealed a bright line correspondingto the compositional fluctuation and impurity adsorption, and indicated noncommutative structures ofAlGaAs/GaAs and GaAs/AlGaAs interfaces. High performance HBTs and DBRTDs were obtained bycontinuously grown method while growth interruption caused performance degradation. It was concluded thatgrowth interruption may cause accumulation of residua1 impurities in the ambient as well as compositionalfluctuation while continuous growth at very low growth rates can overcome such problems.     

Quantitative mass spectrometry for colorectal cancer proteomics

This review documents the uses of quantitative MS applied to colorectal cancer (CRC) proteomics for biomarker discovery and molecular pathway profiling. Investigators are adopting various labeling and label-free MS approaches to quantitate differential protein levels in cells, tumors, and plasma/serum. We comprehensively review recent uses of this technology to examine mouse models of CRC, CRC cell lines, their secretomes and subcellular fractions, CRC tumors, CRC patient plasma/serum, and stool samples. For biomarker discovery these approaches are uncovering proteins with potential diagnostic and prognostic utility, while in vitro cell culture experiments are characterizing proteomic and phosphoproteomic responses to disrupted signaling pathways due to mutations or to inhibition of drugable enzymes.     

Visualization of diversity in large multivariate data sets

Understanding the diversity of a set of multivariate objects is an important problem in many domains, including ecology, college admissions, investing, machine learning, and others. However, to date, very little work has been done to help users achieve this kind of understanding. Visual representation is especially appealing for this task because it offers the potential to allow users to efficiently observe the objects of interest in a direct and holistic way. Thus, in this paper, we attempt to formalize the problem of visualizing the diversity of a large (more than 1000 objects), multivariate (more than 5 attributes) data set as one worth deeper investigation by the information visualization community. In doing so, we contribute a precise definition of diversity, a set of requirements for diversity visualizations based on this definition, and a formal user study design intended to evaluate the capacity of a visual representation for communicating diversity information. Our primary contribution, however, is a visual representation, called the Diversity Map, for visualizing diversity. An evaluation of the Diversity Map using our study design shows that users can judge elements of diversity consistently and as or more accurately than when using the only other representation specifically designed to visualize diversity.     

Facilitation of consumer loyalty toward branded applications: The dual-route perspective

Although many brands develop mobile applications (apps) to build relationships with consumers, most branded apps fail to retain consumers’ loyalty. This study examines the facilitation of consumer loyalty toward branded apps (continuance intention, in-app purchase intention, and word-of-mouth intention) from the dual-route perspective. One route is the affective (relationship) route, where brand benefits (functional benefits, experiential benefits, symbolic benefits, and monetary benefits) drive parasocial interactions between consumers and the brand, which, in turn, influences branded app loyalty. The other route is the utility route, where system characteristics (system quality and information quality) affect perceived usefulness, which, in turn, facilitates branded app loyalty. An online survey was conducted, and the research model was empirically tested using partial least squares structural equation modeling. The findings support the dual-route perspective according to which both affective and utilitarian paths facilitate branded app loyalty. The key theoretical contribution of this study is that it moves beyond the utilitarian path and finds the affective (relationship) path to give a more complete picture of the facilitation of consumer loyalty in the branded app context. A strategy is provided to suggest to practitioners how to design branded apps to facilitate consumer loyalty.     

Limits and potentials to deliberative engagement in highly regulated planning systems: Norm development within fixed rules

Planning practice requires ongoing interaction between regulatory “facts” and deliberative “norms”. Played out in local and strategic developments, “norms” are the agreed values and positions developed by advancing deliberative engagement of residents; while “facts” are the more rigid statutory procedures through which planning decisions are typically made. However, conflict arises between residents' groups and local government decision-makers when deliberative norms, now a key tenet of strategic planning processes, struggle to gain traction in the factual spaces provided by statutory planning regulations. A contentious planning process in St Kilda, Melbourne, Australia (concerning the redevelopment of a car park into a commercial and public space) highlights the challenges to deliberative engagement in highly-regulatory planning systems. Drawing on this contested case, this paper examines how the broader formal and relatively fixed framework of regulatory-based decision-making fails to support participatory principles, undermining both the desired communicative ethos and enduring collaborative outcomes and norm development. Specifically, the paper problematises tensions between residents' growing expectations for greater transparency and participation in planning, arising from a growing regard for deliberation in strategic planning, and the hegemonic nature of statutory planning that preserves planning control within the formal domain of government and the private sector.     

Genetically engineered brain drug delivery vectors: cloning, expression and in vivo application of an anti-transferrin receptor single chain antibodystreptavidin fusion gene and protein

A single chain Fv antibody–streptavidin fusion proteinwas expressed and purified from bacterial inclusion bodies followingcloning of the genes encoding the variable region of the heavychain and light chain of the murine OX26 monoclonal antibodyto the rat transferrin receptor. The latter undergoes receptormediated transcytosis through the brain capillary endothelialwall in vivo, which makes up the blood–brain barrier (BBB);therefore, the OX26 monoclonal antibody and its single chainFv analog may act as brain drug delivery vectors in vivo. Attachmentof biotinylated drugs to the antibody vector is facilitatedby production of the streptavidin fusion protein. The bi-functionalityof the OX26 single chain Fv antibody–streptavidin fusionprotein was retained, as the product both bound biotin and therat transferrin receptor in vitro and in vivo, based on pharmacokineticand brain uptake analyses in anesthetized rats. The attachmentof biotin–polyethyleneglycol–fluorescein to theOX26 single chain Fv antibody–streptavidin fusion proteinresulted in illumination of isolated rat brain capillaries inconfocal fluorescent microscopy. In conclusion, these studiesdemonstrate that genetically engineered single chain Fv antibody–streptavidinfusion proteins may be used for non-invasive neurotherapeuticdelivery to the brain using endogenous BBB transport systemssuch as the transferrin receptor.     

三种新激光染料的双光子吸收荧光和上转换激射

用实验方法研究了三种新激光染料PSPI,DEASPI和HEASPI的双光子吸收荧光和上转换激射。它们的二甲基酰胺溶液在锁模Nd∶YAG激光器 10 64nm红外光照射下 ,发射出很强的红色可见荧光和激射光。荧光峰值和激射波长分别位于～ 648nm和～ 62 4nm。实验测得DEASPI,PSPI和HEASPI的二甲基酰胺溶液的上转换激射效率高达 10 7% ,9 8%和 7 1%。