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Walnut blight is a significant above-ground disease of walnuts caused by Xanthomonas arboricola pv. juglandis (Xaj). The secreted form of chorismate mutase (CM), a key enzyme of the shikimate pathway regulating plant immunity, is highly conserved between plant-associated beta and gamma proteobacteria including phytopathogens belonging to the Xanthomonadaceae family. To define its role in walnut blight disease, a dysfunctional mutant of chorismate mutase was created in a copper resistant strain Xaj417 (XajCM). Infections of immature walnut Juglans regia (Jr) fruit with XajCM were hypervirulent compared with infections with the wildtype Xaj417 strain. The in vitro growth rate, size and cellular morphology were similar between the wild-type and XajCM mutant strains, however the quantification of bacterial cells by dPCR within walnut hull tissues showed a 27% increase in XajCM seven days post-infection. To define the mechanism of hypervirulence, proteome analysis was conducted to compare walnut hull tissues inoculated with the wild type to those inoculated with the XajCM mutant strain. Proteome analysis revealed 3296 Jr proteins (five decreased and ten increased with FDR ≤ 0.05) and 676 Xaj417 proteins (235 increased in XajCM with FDR ≤ 0.05). Interestingly, the most abundant protein in Xaj was a polygalacturonase, while in Jr it was a polygalacturonase inhibitor. These results suggest that this secreted chorismate mutase may be an important virulence suppressor gene that regulates Xaj417 virulence response, allowing for improved bacterial survival in the plant tissues.

We showed previously that gallic acid is produced in walnut from 3-dehydroshikimate by a shikimate dehydrogenase (JrSkDH). This study focuses on the next step in the hydrolysable tannin pathway, the formation of 1-O-galloyl-β-D-glucose from the phenolic gallic acid and UDP glucose by a glycosyltransferase. JrGGT1 (UGT84A73) and JrGGT2 (UGT84A74) are predicted to be two such glycosyltransferases, which we expressed in tobacco plants. GC-MS analysis of the transgenic tobacco revealed moderate, yet significant alterations in plant secondary metabolism, such as depleted phenolic acids, including gallic acid. We postulate that these effects are due to JrGGT1 and JrGGT2 activity, as JrGGT orthologs glycosylate these phenolic compounds in vitro. Moreover, JrGGT expression in tobacco caused upregulation of shikimic acid pathway metabolites and differing responses in phenylpropanoids, such as phenolic acids and flavonoids. In transcriptome analysis of walnut pellicle tissues, both JrGGTs showed substantial and significant expression correlations with the gallic acid-producing JrSkDHs and were highly coexpressed with the genetic circuits constituting the shikimic acid and phenylpropanoid biosynthetic pathways. Verification of JrGGT gene expression by transcriptome analysis of 20 walnut tissues revealed striking similarities with that of the pellicle data, with the greatest expression in roots, wood, buds, and leaves of Juglans regia cv. Chandler: tissues that typically accumulate hydrolysable tannins. Like the transgenic tobacco, pellicle metabolomic analyses revealed that many phenylpropanoids correlated negatively with JrGGT expression, while shikimic acid pathway metabolites correlated positively with JrGGT expression. This research supports the hypothesis that JrGGT1 and JrGGT2 play non-trivial roles in metabolism of phenolic acids, flavonoids, and ostensibly, tannins.

Walnut blight is a significant above-ground disease of walnuts caused by Xanthomonas arboricola pv. juglandis (Xaj). The secreted form of chorismate mutase (CM), a key enzyme of the shikimate pathway regulating plant immunity, is highly conserved between plant-associated beta and gamma proteobacteria including phytopathogens belonging to the Xanthomonadaceae family. To define its role in walnut blight disease, a dysfunctional mutant of chorismate mutase was created in a copper resistant strain Xaj417 (XajCM). Infections of immature walnut Juglans regia (Jr) fruit with XajCM were hypervirulent compared with infections with the wildtype Xaj417 strain. The in vitro growth rate, size and cellular morphology were similar between the wild-type and XajCM mutant strains, however the quantification of bacterial cells by dPCR within walnut hull tissues showed a 27% increase in XajCM seven days post-infection. To define the mechanism of hypervirulence, proteome analysis was conducted to compare walnut hull tissues inoculated with the wild type to those inoculated with the XajCM mutant strain. Proteome analysis revealed 3296 Jr proteins (five decreased and ten increased with FDR ≤ 0.05) and 676 Xaj417 proteins (235 increased in XajCM with FDR ≤ 0.05). Interestingly, the most abundant protein in Xaj was a polygalacturonase, while in Jr it was a polygalacturonase inhibitor. These results suggest that this secreted chorismate mutase may be an important virulence suppressor gene that regulates Xaj417 virulence response, allowing for improved bacterial survival in the plant tissues.

Walnuts (Juglans regia L.) are a valuable dietary source of polyphenols and lipids, with increasing worldwide consumption. California is a major producer, with 'Chandler' and 'Tulare' among the cultivars more widely grown. 'Chandler' produces kernels with extra light color at a higher frequency than other cultivars, gaining preference by growers and consumers. Here we performed a deep comparative proteome analysis of kernel pellicle tissue from these two valued genotypes at three harvest maturities, detecting a total of 4937 J. regia proteins. Late and early maturity stages were compared for each cultivar, revealing many developmental responses common or specific for each cultivar. Top protein biomarkers for each developmental stage were also selected based on larger fold-change differences and lower variance among replicates, including proteins for biosynthesis of lipids and phenols, defense-related proteins and desiccation stress-related proteins. Comparison between the genotypes also revealed the common and specific protein repertoires, totaling 321 pellicle proteins with differential abundance at harvest stage. The proteomics data provides clues on antioxidant, secondary, and hormonal metabolism that could be involved in the loss of quality in the pellicles during processing for commercialization.

Addressing mental and behavioral health effects of disaster media coverage is an important part of a disaster public health response, and school staff may be particularly well suited to help children and youth cope with disaster media. We conducted qualitative interviews (N = 42) to explore US school staff (e.g., teachers, mental health staff, administrators) perspectives on disaster media coverage and students and used an inductive thematic method for analysis. We found that school staff reported that students often exhibited reactions to disaster media that included expressing emotions and asking questions. With regard to school staff coping efforts with students, participants described different ways they talked with students about disaster media, but also reported a need for help with these conversations.

Objective: The purpose of this pilot study was to evaluate the Resilience and Coping Intervention (RCI) with college students. Participants: College students (aged 18-23) from a large Midwest US university who volunteered for a randomized controlled trial during the 2015 spring semester. Methods: College students were randomly assigned to an intervention (n = 64) or a control (n = 65) group. Intervention participants received three 45-minute RCI sessions over subsequent weeks. All participants completed pre- and post-intervention assessments at the beginning of Week 1 and end of Week 3. Student resilience, coping, hope, stress, depression, and anxiety were assessed. Results. RCI participants reported significantly more hope and less stress and depression from Week 1 to Week 3 compared with control participants. Results for resilience also approached statistical significance. Effect sizes were small to moderate. Conclusions: This study found preliminary evidence that RCI is an effective resilience intervention for use with college students.

This study examined deployment effects in children and spouses of National Guard troops using a longitudinal design to assess 18 children (ages 6 to 17 years) and 13 nondeployed spouses before, during, and after deployment. Both self- and parent reports revealed that children of deployed service personnel experienced emotional and behavioral symptoms during the deployment of their fathers relative to pre- and post-deployment. The children's worry and uncertainty, along with aspects of family interactions, may give rise to ambiguous loss associated with deployment in military families. (Contains 3 tables.)

Focus groups were conducted with 23 children and adolescents, aged 9 to 17 years, who relocated from Louisiana to Texas following Hurricane Katrina to explore their disaster, evacuation, and resettlement experiences. The resilience described by some was remarkable and, despite evidence of cultural disparity and stigma, many identified positive aspects of the new communities in which they resided. Attempts to help displaced children must begin with a full understanding of the individual experiences and reactions of those being served rather than being based on assumptions about what may have occurred.

Media coverage of disasters is often pervasive, continuous, and intense. Because media use has been found to influence the way that individuals view the world, it is worth reviewing how such coverage affects children who do not directly experience a disaster. This article reviews what is known about how disaster coverage in traditional media (i.e., newspapers, television) and new media (i.e., Internet, cell phones) impacts youth who do not directly experience the disaster. To date, the impact of new media disaster coverage on youth has received little attention in the scientific literature. However, by considering what is known about how traditional media disaster coverage impacts youth and combining that knowledge with an understanding of the specific structure of new media, this article is able to provide new media usage recommendations for parents and clinicians to utilize with children following a disaster. This article also discusses potential positive outcomes that could result when youth are exposed to media disaster coverage. (Contains 4 tables.)

A number of factors can contribute to youth's reactions to disasters. These factors can include characteristics of the event; the nature of youth's exposure; and individual, family, and social predictors. This article describes both outcomes and predictors in order to prepare professionals who might work with youth in post-disaster situations. (Contains 1 table.)