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Pre-exposure to uninfected sand fly bites (USFB) protects against Leishmania major infection. Little is known about the initial immune response responsible for this protection. During blood feeding, the insect sand fly inoculates Leishmania parasites into the skin alongside saliva. Here, we explore the early inflammatory response in the skin of pre-exposed (PE) mice challenged with L. major-infected P. duboscqi flies. The relative expression of cytokines and chemokines by skin cells were investigated 2- 48h post-infection using a macroarray (Oligo GEArray®). There is a rapid and strong early expression of inflammatory genes in PE compared to naive mice following challenge. Two to twelve hours post-infection, naïve mice showed an increased expression of MCP-1, MCP-3 and eotaxin that attract macrophages and granulocytes while PE mice upregulated TCA-3, BRAK and I-TAC related to migration of NK cells, macrophages, granulocytes and activated T cells. Characterization of leukocytes by FACS 24-48h post-infection showed a significantly increased recruitment of neutrophils, NK cells, macrophages and CD4+ cells in PE mice. PE mice also presented a higher frequency of IFN-γ producing CD4+ and NK cells 24h post-infection. This suggests that induced cytokines and chemokines are altered by pre-exposure to USFB. Thus, protection from Leishmania infection observed in PE mice may result from Th1 priming by an anti-saliva immunity that acts in concert with a modulated innate immune response.

A notion of effective gauge fields which does not involve a background metric is introduced. The role of scale is played by cellular decompositions of the base manifold. Once a cellular decomposition is chosen, the corresponding space of effective gauge fields is the space of flat connections with singularities on its codimension two skeleton, ${\cal A}_{C-flat} \subset \bar{\cal A}_M$. If cellular decomposition $C_2$ is finer than cellular decomposition $C_1$, there is a coarse graining map $\pi_{C_2 \to C_1}: {\cal A}_{C_2-flat} \to {\cal A}_{C_1-flat}$. We prove that the triple $({\cal A}_{C_2-flat}, \pi_{C_2 \to C_1}, {\cal A}_{C_1-flat})$ is a principal fiber bundle with a preferred global section given by the natural inclusion map $i_{C_1 \to C_2}: {\cal A}_{C_1-flat} \to {\cal A}_{C_2-flat}$. Since the spaces ${\cal A}_{C-flat}$ are partially ordered (by inclusion) and this order is directed in the direction of refinement, we can define a continuum limit, $C \to M$. We prove that, in an appropriate sense, $\lim_{C \to M} {\cal A}_{C-flat} = \bar{\cal A}_M$. We also define a construction of measures in $\bar{\cal A}_M$ as the continuum limit (not a projective limit) of effective measures., Comment: 29 pages, 2 figures

Fresh apricots (Prunus armeniaca L.) are in high demand, but are available for only a short period during the Spring and the beginning of the Summer. There is no information on the correct harvest maturity stage that should be chosen to ensure a long post-harvest life and high sensory quality. The objective of this study was to evaluate the effect of maturity stage at harvest oil the sensory quality of 'Palsteyn' apricots after 14, 28, or 42 d in cold storage. Sourness, flavour, and acceptability showed major changes during cold storage. Ripe fruit (orange-yellow skin colour) showed the highest acceptability, as assessed by a "mini-consumer test" (i.e., an untrained panel: n = 36). Fruit harvested at an intermediate stage of maturity (light yellow skin colour) reached all average acceptability, while unripe fruit (greenish skin colour) were not acceptable. After 28 d of cold storage, fruits were still acceptable; but, after 42 d, fruits reached the "dislike" zone. On a principal component analysis, acceptability was shown to be positively associated with, juiciness, and aroma. and negatively associated with sourness. After 28 d and 42 d of cold storage, sweetness, flavour. unripe fruit appeared to have low acceptability and quality attributes. 'Palsteyn' apricot harvested with all orange-yellow skin colour, as the least ripe fruits, showed that they could reach high sensory quality standards and were able to withstand long periods of cold storage.

Kiwifruit breeding still largely relies on phenotypic observation of cross progeny grown in the field to fruiting maturity, without any selection prior to juvenility being overcome. Developing marker-assisted selection for traits of interest would greatly help breeders to screen rapidly breeding populations, thereby saving costs and labor. With the aim of mapping several characters of interest in kiwifruit, a pseudo test-cross population of diploid Actinidia chinensis was produced by crossing parents with contrasting phenotypic traits. Ninety-four individuals were analysed to obtain a saturated genetic map based on 167 SSRs retrieved from the literature and 9,397 segregating loci obtained through haplotype calling of SNP markers identified by a modified ddRAD protocol as proposed by Peterson et al. (2012). To improve the accuracy of genotype calling, restriction site-associated reads were aligned to the scaffolds of the recently published kiwifruit genome (Huang et al., 2013). This strategy provided genetic anchoring to 557M bp (90%) of the available assembly, helping also to anchor some unmapped 120 Mbp and to identify some mis-joined scaffolds. Phenotypic traits, such as gender, bud burst, flowering time, fruit weight, flesh color, sugar content, pH and flesh acidity, were recorded during two consecutive seasons in individual seedlings of both populations. Several genetic determinants of traits were mapped and markers for selection are being identified. The methodological approach to the production of linkage maps based on genotyping-by-sequencing strategy together with the mapping of genetic determinants of several phenotypic traits are presented and discussed.