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The prevailing 'division of labor' concept in cellular immunity is that CD8+ T cells primarily utilize cytotoxic functions to kill target cells, while CD4+ T cells exert helper/inducer functions. Multiple subsets of CD4+ memory T cells have been characterized by distinct chemokine receptor expression. Here, we demonstrate that analogous CD8+ memory T-cell subsets are present characterized by identical chemokine receptor expression signatures. Among them, Tc2, Tc17 and Tc22 cells, in contrast to Tc1 and Tc17+1 cells, expressed IL-6R but not SLAMF7, completely lacked cytotoxicity and instead displayed helper functions including CD40L expression. CD8+ helper T cells exhibited a unique TCR repertoire, expressed genes related to skin resident memory T cells (TRM) and were altered in the inflammatory skin disease psoriasis. Our findings provide evidence that the conventional view of CD4+ and CD8+ T cell capabilities and functions in human health and disease needs to be revised.

Greek unifloral honeys (pine, thyme, fir, orange blossom) were characterized and classified according to botanical origin based on phenolic compound content and conventional physicochemical parameters using MANOVA and Linear Discriminant Analysis. One hundred and nineteen honey samples were collected during the harvesting period 2011 from 14 different regions in Greece known to produce unifloral honey of good quality. The analysis of phenolic compounds quercetin (3,5,7,3′,4′-pentahydroxyflavone), myricetin (3,5,7,3′,4′,5′-hexahydroxyflavone), kaempferol (3,5,7,4′-tetrahydroxyflavone), chrysin (5,7-dihydroxyflavanone), and syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid), was performed by high pressure liquid chromatography. Conventional quality parameter analysis included the determination of: pH, free, lactonic and total acidity, electrical conductivity, moisture, ash, as well as lactonic/free acidity ratio and colour parameters L*, a*, and b*. Using 4 phenolic compounds and 10 conventional quality parameters honey samples were satisfactorily classified (96.6% correct prediction) according to botanical origin.

We consider a new workload allocation policy addressing fairness for user level performance measures. More specifically the criterion used for optimal workload allocation is the one which minimizes the maximum expected response time at computer systems to which jobs are routed. The policy to attain this criterion is therefore referred to as the min-max policy (MMP). It is shown that this optimization criterion is tantamount to routing to the fastest M processors, where M depends on system statistics and equalizing the expected response times on these processors. The algorithm to compute job routing probabilities is applicable to increasing continuous functions of system response time versus the job arrival rate. We next investigate some properties of the MMP and show that it results in minimizing the coefficient of variation of response time when the job processing times are exponentially distributed. We compare the MMP with the one that minimizes the mean overall response time. It is shown that the new policy attains fairness by equalizing the mean response times at different systems, at a tolerable increase in overall response time. Finally, we report on a sensitivity analysis with respect to changes in job arrival rate and errors in estimating this rate.

Workloads in distributed database applications consist of queries and transactions. In order to address performance requirements, distributed transaction processing systems have to deal with two related issues: transaction routing and scheduling. Due to the distribution of data objects among nodes and the access cost incurred by remote accesses, efficient transaction routing is an important consideration for overall system performance. Another important consideration is workflow scheduling and routing. Workflows are complex units of work consisting of multiple, possibly interdependent, transactions. In this survey, we discuss a number of different transaction routing mechanisms and their performance.