Animal Defenses against Infectious Agents: Is Damage Control More Important Than Pathogen Control?

The ability of hosts to withstand a given number of pathogens is a critical component of health. Now playing catch-up with plant biologists, animal biologists are starting to formally separate this form of defense from classical resistance

The Vehicle, Fall 1985

Vol. 27, No. 1 Table of Contents Satchel AssMichael D. Smithpage 3 PhotoDoug Andersonpage 7 CounselingChristy Dunphypage 8 Grave SiteJay D. Fiskpage 8 Sight-Seeing Outside PhoenixBob Zordanipage 9 PerformanceDan Von Holtenpage 10 NightmareKandy Bellpage 10 Photo (The Loft)Lawrence McGownpage 11 LaboringJanet Gracepage 12 Blood DonorDan Von Holtenpage 13 Photo (Pier)Lawrence McGownpage 14 ExamplesChristopher Albinpage 14 Three PoemsPatrick Peterspage 15 Sometimes I Dream in Cotton CandyKathy Graypage 16 One Day While BoatingF. Link Rapierpage 17 DepartureBob Zordanipage 17 140 Print That\u27s Life Peter Dowlingpage 18 Photo (Around the Bend)Mike Freckerpage 20 Light ConversationDan Hintzpage 22 She Waits For the WorldJim Harrispage 22 HoneyKathy Graypage 23 Photo AlbumPatrick Peterspage 24 Photo (Stairs)Lawrence McGownpage 25 Fallen From Grace to SaturdayF. Link Rapierpage 26 Post MortemF. Link Rapierpage 27 ConfessionJohn Kayserpage 27 Child\u27s PlayChristopher Albinpage 27 Seeking A Friend\u27s Advice on DietingKathy Graypage 28 PhotoDoug Andersonpage 28 She Came Back to MeJim Harrispage 29 Farm BoyDiana Winsonpage 30 DilemmaJanet Wilhelmpage 31 In a Rock or StoneRichard Donnellypage 32 In November He Came To MeJean Kover Chandlerpage 33 EndingChristy Dunphypage 34 The Honor GradEddie Simpsonpage 35 Photo (Thirst)Mike Freckerpage 40https://thekeep.eiu.edu/vehicle/1046/thumbnail.jp

Antecedents to value diminution: A dyadic perspective

© 2016, © The Author(s) 2016. The purpose of this article is to identify the antecedents of diminished value in business-to-business exchange. There is only a limited amount of research on value destruction in the context of service-dominant (S-D) logic and, to the best of our knowledge, no dyadic studies. From a business perspective, awareness of factors that have the potential to impede value creation will enable relationship partners to increase mutual value realization. The article examines the accuracy of the term ‘value co-destruction’ as a blanket description for interaction that results in value reduction, and proposes that, in many instances, ‘value diminution’ may be more appropriate. The study adopts an exploratory, qualitative approach. One-to-one interviews are conducted with clients and their creative agencies. The results suggest that diminished value outcomes are caused by resource deficiencies and resource misuse by both relational partners, separately and jointly. We propose a model of five higher-order antecedents of value diminution: absence of trust, inadequate communication, power/dependence imbalance, inadequate coordination and inadequate human capital

Do Children with Fragile X Syndrome Show Declines or Plateaus in Adaptive Behavior?

This study explores if children with fragile X syndrome (FXS) show advances, declines, or plateaus in adaptive behavior over time and the relationship of nonverbal cognitive abilities and autistic behavior on these trajectories. Parents of 55 children with FXS completed the Vineland Adaptive Behavior Scales between 3 and 6 times from 2 to 10 years of age. Using raw scores, results indicate that about half of the sample showed advances in adaptive behavior, while the other half showed declines, indicating a regression in skills. Children who were more cognitively advanced and had less autistic behaviors had higher trajectories. Understanding the developmental course of adaptive behavior in FXS has implications for educational planning and intervention, especially for those children showing declines

Tracing Personalized Health Curves during Infections

By concentrating on the relationship between health and microbe number over the course of infections, most pathogenic and mutualistic infections can be summarized by a small alphabet of curves, which has implications not only for basic research but for how we might treat patients

Dissecting the Genetic Architecture of Host–Pathogen Specificity

International audienc

Natural Variation in Partial Resistance to Pseudomonas syringae Is Controlled by Two Major QTLs in Arabidopsis thaliana

BACKGROUND: Low-level, partial resistance is pre-eminent in natural populations, however, the mechanisms underlying this form of resistance are still poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we used the model pathosystem Pseudomonas syringae pv. tomato DC3000 (Pst) - Arabidopsis thaliana to study the genetic basis of this form of resistance. Phenotypic analysis of a set of Arabidopsis accessions, based on evaluation of in planta pathogen growth revealed extensive quantitative variation for partial resistance to Pst. It allowed choosing a recombinant inbred line (RIL) population derived from a cross between the accessions Bayreuth and Shahdara for quantitative genetic analysis. Experiments performed under two different environmental conditions led to the detection of two major and two minor quantitative trait loci (QTLs) governing partial resistance to Pst and called PRP-Ps1 to PRP-Ps4. The two major QTLs, PRP-Ps1 and PRP-Ps2, were confirmed in near isogenic lines (NILs), following the heterogeneous inbred families (HIFs) strategy. Analysis of marker gene expression using these HIFs indicated a negative correlation between the induced amount of transcripts of SA-dependent genes PR1, ICS and PR5, and the in planta bacterial growth in the HIF segregating at PRP-Ps2 locus, suggesting an implication of PRP-Ps2 in the activation of SA dependent responses. CONCLUSIONS/SIGNIFICANCE: These results show that variation in partial resistance to Pst in Arabidopsis is governed by relatively few loci, and the validation of two major loci opens the way for their fine mapping and their cloning, which will improve our understanding of the molecular mechanisms underlying partial resistance

Contributions of phonological and verbal working memory to language development in adolescents with fragile X syndrome

Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability. Although language delays are frequently observed in FXS, neither the longitudinal course of language development nor its cognitive predictors are well understood. The present study investigated whether phonological and working memory skills are predictive of growth in vocabulary and syntax in individuals with FXS during adolescence. Forty-four individuals with FXS (mean age = 12.61 years) completed assessments of phonological memory (nonword repetition and forward digit recall), verbal working memory (backward digit recall), vocabulary, syntax, and nonverbal cognition. Vocabulary and syntax skills were reassessed at a 2-year follow-up. In a series of analyses that controlled for nonverbal cognitive ability and severity of autism symptoms, the relative contributions of phonological and working memory to language change over time were investigated. These relationships were examined separately for boys and girls. In boys with FXS, phonological memory significantly predicted gains in vocabulary and syntax skills. Further, verbal working memory was uniquely associated with vocabulary gains among boys. In girls with FXS, phonological and working memory skills showed no relationship with language change across the 2-year time period. Our findings indicate that, for adolescent boys with FXS, acquisition of vocabulary and syntax may be constrained by the ability to maintain and manipulate phonological representations online. Implications for the identification and treatment of language disorders in this population are discussed. The present study is the first to identify specific cognitive mechanisms contributing to language growth over time in individuals with FXS

The Relationship of Within-Host Multiplication and Virulence in a Plant-Virus System

Background. Virulence does not represent any obvious advantage to parasites. Most models of virulence evolution assume that virulence is an unavoidable consequence of within-host multiplication of parasites, resulting in trade-offs between within-host multiplication and between-host transmission fitness components. Experimental support for the central assumption of this hypothesis, i.e., for a positive correlation between within-host multiplication rates and virulence, is limited for plant-parasite systems. Methodology/Principal Findings. We have addressed this issue in the system Arabidopsis thaliana-Cucumber mosaic virus (CMV). Virus multiplication and the effect of infection on plant growth and on viable seed production were quantified for 21 Arabidopsis wild genotypes infected by 3 CMV isolates. The effect of infection on plant growth and seed production depended of plant architecture and length of postembryonic life cycle, two genetically-determined traits, as well as on the time of infection in the plant's life cycle. A relationship between virus multiplication and virulence was not a general feature of this host-parasite system. This could be explained by tolerance mechanisms determined by the host genotype and operating differently on two components of plant fitness, biomass production and resource allocation to seeds. However, a positive relationship between virus multiplication and virulence was detected for some accessions with short life cycle and high seed weight to biomass ratio, which show lower levels of tolerance to infection. Conclusions/Significance. These results show that genotype-specific tolerance mechanisms may lead to the absence of a clear relationship between parasite multiplication and virulence. Furthermore, a positive correlation between parasite multiplication and virulence may occur only in some genotypes and/or environmental conditions for a given host-parasite system. Thus, our results challenge the general validity of the trade-off hypothesis for virulence evolution, and stress the need of considering the effect of both the host and parasite genotypes in analyses of host-parasite interactions. © 2007 Pagán et al.Ministerio de Educación y Ciencia, Spain.Peer Reviewe

The Relationship of Within-Host Multiplication and Virulence in a Plant-Virus System

Background. Virulence does not represent any obvious advantage to parasites. Most models of virulence evolution assume that virulence is an unavoidable consequence of within-host multiplication of parasites, resulting in trade-offs between within-host multiplication and between-host transmission fitness components. Experimental support for the central assumption of this hypothesis, i.e., for a positive correlation between within-host multiplication rates and virulence, is limited for plant-parasite systems. Methodology/Principal Findings. We have addressed this issue in the system Arabidopsis thaliana-Cucumber mosaic virus (CMV). Virus multiplication and the effect of infection on plant growth and on viable seed production were quantified for 21 Arabidopsis wild genotypes infected by 3 CMV isolates. The effect of infection on plant growth and seed production depended of plant architecture and length of postembryonic life cycle, two genetically-determined traits, as well as on the time of infection in the plant's life cycle. A relationship between virus multiplication and virulence was not a general feature of this host-parasite system. This could be explained by tolerance mechanisms determined by the host genotype and operating differently on two components of plant fitness, biomass production and resource allocation to seeds. However, a positive relationship between virus multiplication and virulence was detected for some accessions with short life cycle and high seed weight to biomass ratio, which show lower levels of tolerance to infection. Conclusions/Significance. These results show that genotype-specific tolerance mechanisms may lead to the absence of a clear relationship between parasite multiplication and virulence. Furthermore, a positive correlation between parasite multiplication and virulence may occur only in some genotypes and/or environmental conditions for a given host-parasite system. Thus, our results challenge the general validity of the trade-off hypothesis for virulence evolution, and stress the need of considering the effect of both the host and parasite genotypes in analyses of host-parasite interactions. © 2007 Pagán et al.Ministerio de Educación y Ciencia, Spain.Peer Reviewe