bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial spot of tomato and pepper: diverse Xanthomonas species with a wide variety of virulence factors posing a worldwide challenge
Authors: Potnis Neha , Timilsina Sujan , Strayer Amanda , Shantharaj Deepak , Barak Jeri D. , Paret Mathews L. , Vallad Gary E. , Jones Jeffrey B. 
Published: February 2015

SummaryTaxonomic statusBacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadaceae; Genus Xanthomonas; Species Xanthomonas euvesicatoria, Xanthomonas vesicatoria, Xanthomonas perforans and Xanthomonas gardneri.Microbiological propertiesGram‐negative, rod‐shaped bacterium, aerobic, motile, single polar flagellum.Host rangeCauses bacterial spot disease on plants belonging to the Solanaceae family, primarily tomato (Solanum lycopersicum), pepper (Capsicum annuum) and chilli peppers (Capsicum frutescens).Disease symptomsNecrotic lesions on all above‐ground plant parts.DistributionWorldwide distribution of X. euvesicatoria and X. vesicatoria on tomato and pepper; X. perforans and X. gardneri increasingly being isolated from the USA, Canada, South America, Africa and Europe.A wide diversity within the bacterial spot disease complex, with an ability to cause disease at different temperatures, makes this pathogen group a worldwide threat to tomato and pepper production. Recent advances in genome analyses have revealed the evolution of the pathogen with a plethora of novel virulence factors. Current management strategies rely on the use of various chemical control strategies and sanitary measures to minimize pathogen spread through contaminated seed. Chemical control strategies have been a challenge because of resistance by the pathogen. Breeding programmes have been successful in developing commercial lines with hypersensitive and quantitative resistance. However, durability of resistance has been elusive. Recently, a transgenic approach has resulted in the development of tomato genotypes with significant levels of resistance and improved yield that hold promise. In this article, we discuss the current taxonomic status, distribution of the four species, knowledge of virulence factors, detection methods and strategies for disease control with possible directions for future research.
Strong altitudinal partitioning in the distributions of ectomycorrhizal fungi along a short (300 m) elevation gradient
Authors: Jarvis Susan G. , Woodward Steve , Taylor Andy F. S. 
Published: February 2015

Summary

Changes in species richness and distributions of ectomycorrhizal (ECM) fungal communities along altitudinal gradients have been attributed to changes in both host distributions and abiotic variables. However, few studies have considered altitudinal relationships of ECM fungi associated with a single host to identify the role of abiotic drivers. To address this, ECM fungal communities associated with one host were assessed along five altitudinal transects in Scotland.

Roots of Scots pine (Pinus sylvestris) were collected from sites between 300 and 550–600 m altitude, and ECM fungal communities were identified by 454 pyrosequencing of the fungal internal transcribed spacer (ITS) region. Soil moisture, temperature, pH, carbon : nitrogen (C : N) ratio and organic matter content were measured as potential predictors of fungal species richness and community composition.

Altitude did not affect species richness of ECM fungal communities, but strongly influenced fungal community composition. Shifts in community composition along the altitudinal gradient were most clearly related to changes in soil moisture and temperature.

Our results show that a 300 m altitudinal gradient produced distinct shifts in ECM fungal communities associated with a single host, and that this pattern was strongly related to climatic variables. This finding suggests significant climatic niche partitioning among ECM fungal species.
Does Training Matter? Evidence from Performance Management Reforms
Authors: Kroll Alexander , Moynihan Donald P. 
Published: February 2015

AbstractTraining is much discussed but rarely studied in public management. Using multiple waves of survey data, the authors examine the effects of training on the implementation of performance management reforms in the U.S. federal government, asking whether those exposed to training are more likely to use performance data and strategic goals when making decisions. Training is positively associated with reform implementation, but there is little evidence that this association can be explained by the development of specific capacities to overcome performance management challenges. The findings offer two implications for the practice and study of training. The authors propose that training is likely to succeed if it is designed and funded to close specific capacity gaps needed for successful reform implementation. However, it is also necessary to better understand alternative causal mechanisms by which training facilitates reform implementation, such as explaining and justifying reforms.Practitioner Points
Training can facilitate the implementation of new policies by providing information about the policies, justifying why they are needed, and giving employees the capacity to put the new policies in place.
Using training to build specific employee capacities is more complex, resource intensive, and rare than using training to provide information and justify reforms.
Effective training in government requires not just more resources but also better understanding of the specific capacities needed and how to create them—research can help by identifying the most significant capacity gaps in policy implementation.
Citizen (Dis)satisfaction: An Experimental Equivalence Framing Study
Authors: Olsen Asmus Leth 
Published: February 2015

AbstractThis article introduces the importance of equivalence framing for understanding how satisfaction measures affect citizens’ evaluation of public services. Does a 90 percent satisfaction rate have a different effect than a logically equivalent 10 percent dissatisfaction rate? Two experiments were conducted on citizens’ evaluations of hospital services in a large, nationally representative sample of Danish citizens. Both experiments found that exposing citizens to a patient dissatisfaction measure led to more negative views of public service than exposing them to a logically equivalent satisfaction metric. There is some support for part of the shift in evaluations being caused by a negativity bias: dissatisfaction has a larger negative impact than satisfaction has a positive impact. Both professional experience at a hospital and prior exposure to satisfaction rates reduced the negative response to dissatisfaction rates. The results call for further study of equivalence framing of performance information.Practitioner Points
The valence (positive/negative) of performance information can have substantial effects on citizens’ perception of public services—even if the underlying performance is exactly the same.
Presenting citizens with a dissatisfaction rate of 10 percent induces a much more negative evaluation of public services than presenting them with a logically equivalent satisfaction rate of 90 percent.
Policy makers must carefully consider how minor equivalent changes in the presentation of performance information can induce large shifts in citizens’ perceptions of public service performance.
Faddists, Enthusiasts and Canadian Divas: Broadcasting Quotas and the Supply Response
Authors: Richardson Martin , Wilkie Simon 
Published: February 2015

AbstractThis paper constructs a model of the recorded music market to investigate the consequences of local content requirements in broadcasting for the “internationalization” of domestic music. It models the entry decisions of bands, the contracting decisions of record companies, the airplay decisions of radio stations and the radio listening and recording purchasing decisions of consumers. The paper shows that a local content quota leads, perversely, to the increased internationalization of domestic music. A quota that also requires increased broadcasting of “new” music yields an additional welfare loss but does nothing to a record company's incentives to sign up new bands.
MicroRNA‐155 Deficiency Suppresses Th17 Cell Differentiation and Improves Locomotor Recovery after Spinal Cord Injury
Authors: Yi J. , Wang D. , Niu X. , Hu J. , Zhou Y. , Li Z. 
Published: February 2015

AbstractSpinal cord injury (SCI) is considered to be primarily associated with loss of motor function and leads to activate diverse cellular mechanisms in the central nervous system to attempt to repair the damaged spinal cord tissue. Mir‐155 has been reported to be involved in both innate and adaptive immune responses. But the role of Mir‐155 in spinal cord injury is still unknown. In our current study, Mir‐155 deficiency displays increased myelin sparring and enhanced SC repair process. The number of T cells, B cells and neutrophils are all significantly lower in Mir‐155−/− group than that in WT group after SCI. IL‐17A‐producing cells and the expression of IL‐17A are markedly lower in Mir‐155−/− mice than that in WT mice. We also found higher production of IL‐17 by WT CD4+ T cells than Mir‐155−/− CD4+ T cells in vitro. In our further DC‐T cell coculture system, Mir‐155 deficiency in DCs results in significantly less IL‐17 production from T cells. Furthermore, the inhibited Th17 differentiation induced by Mir‐155 deficiency is partly dependent on increased expression of SOCS1. In conclusion, our present work provides evidence to support the concept that Mir‐155 deficiency suppresses Th17 cell differentiation and improves locomotor recovery after SCI.
Carbon and nitrogen in a Ferralsol under zero‐tillage rotations based on cover, cash or hay crops
Authors: Alburquerque M. A. , Dieckow J. , Sordi A. , Piva J. T. , Bayer C. , Molin R. , Pergher M. , Ribeiro‐Junior P. J. 
Published: February 2015

AbstractTo identify crop rotation systems capable of sequestering C and N to 1 metre depth in a subtropical Ferralsol of Southern Brazil managed under long‐term zero‐tillage (21 yrs), we evaluated six crop sequences: wheat (Triticum aestivum)–soybean (Glycine max) [W‐S], the baseline; oat (Avena strigosa, as cover crop)–maize (Zea mays)–wheat–soybean [O‐M‐W‐S]; vetch (Vicia villosa, as legume cover crop)–maize–wheat–soybean [V‐M‐W‐S]; vetch–maize–oat–soybean–wheat–soybean [V‐M‐O‐S‐W‐S]; ryegrass (Lolium multiflorum, for hay)–maize–ryegrass–soybean [R‐M‐R‐S]; and alfalfa (Medicago sativa, for hay)–maize [A‐M]. Compared to W‐S and to 1 metre, the hay‐based system of A‐M showed the largest C and N sequestration rates (0.50 and 0.06 Mg/ha/yr, respectively). Alfalfa, being a perennial legume under cut‐regrowth cycles, possibly added more C and N through roots. The other hay system, R‐M‐R‐S, also sequestered C efficiently (0.27 Mg/ha/yr), but not N (0.01 Mg/ha/yr). The legume‐based system of V‐M‐W‐S sequestered significant amounts of both C (0.29 Mg/ha/yr) and N (0.04 Mg/ha/yr). The grass‐based system of O‐M‐W‐S showed the lowest sequestration of C (0.09 Mg/ha/yr). In all systems, a positive relationship (R2 = 0.71) occurred between estimated addition of root C and soil C stock to 1 metre. Whenever C and N sequestration occurred, more than half of that occurred below 20 cm depth. Results suggest that adoption of legume‐based systems, perennially as A‐M or annually as V‐M‐W‐S, is efficient for C and N sequestration in subtropical zero‐tillage soils and that roots possibly contribute more to that sequestration than aboveground biomass.
Invasive mold infections in lung and heart‐lung transplant recipients: Stanford University experience
Authors: Vazquez R. , Vazquez‐Guillamet M.C. , Suarez J. , Mooney J. , Montoya J.G. , Dhillon G.S. 
Published: February 2015

AbstractBackgroundRecipients of lung transplantation (LT) and heart‐lung transplantation (HLT) are at increased risk of infection, including invasive mold infections (IMIs). The clinical presentation, radiographic correlates, and outcomes of Aspergillus and non‐AspergillusIMIs in this population have not been well documented.MethodsLT and HLT recipients diagnosed with IMIs between 1990 and 2012 were identified using the Stanford Translational Research Integrated Database Environment and Stanford LT and HLT clinical database. Recipient clinical and radiographic characteristics were obtained via retrospective review of medical records and compared between Aspergillus and non‐Aspergillus mold recipients. Risk factors for mortality were identified using multivariate logistic regression analysis.ResultsDuring the study period, 87 (14%) transplant recipients were diagnosed with IMIs. Aspergillus species were isolated in 63 (72%) and non‐Aspergillus molds in 24 (28%) recipients. No significant difference was seen in presenting symptoms or radiographic findings between Aspergillus and non‐Aspergillus mold recipients. Median time to diagnosis was 363 days in the Aspergillus group and 419 days in the non‐Aspergillus group, with dissemination occurring only within the non‐Aspergillus group (12.5%). Overall 90‐day and 1‐year mortality following IMI was 24% and 44%. One‐year mortality was increased in the non‐Aspergillus group (39.5% vs. 60.5%, P = 0.03).ConclusionsThere is significant overlap in risk factors, presentation, and radiographic patterns in IMI in LT or HLT recipients. Non‐Aspergillus molds were more likely to present late, with disseminated disease, and portend increased 1‐year mortality.
Mechanisms of growth and patterns of gene expression in oxygen‐deprived rice coleoptiles
Authors: Narsai Reena , Edwards Joshua M. , Roberts Thomas H. , Whelan James , Joss Gregory H. , Atwell Brian J. 
Published: February 2015

SummaryColeoptiles of rice (Oryza sativa) seedlings grown under water commonly elongate by up to 1 mm h−1 to reach the atmosphere. We initially analysed this highly specialized phenomenon by measuring epidermal cell lengths along the coleoptile axis to determine elongation rates. This revealed a cohort of cells in the basal zone that elongated rapidly following emergence from the embryo, reaching 200 μm within 12 h. After filming coleoptiles in vivo for a day, kinematic analysis was applied. Eight time‐sliced ‘segments’ were defined by their emergence from the embryo at four‐hourly intervals, revealing a mathematically simple growth model. Each segment entering the coleoptile from the embryo elongated at a constant velocity, resulting in accelerating growth for the entire organ. Consistent with the epidermal cell lengths, relative rates of elongation (mm mm−1 h−1) were tenfold greater in the small, newly emerged basal segments than the older distal tip segments. This steep axial gradient defined two contrasting growth zones (bases versus tips) in which we measured ATP production and protein, RNA and DNA content, and analysed the global transcriptome under steady‐state normoxia, hypoxia (3% O2) and anoxia. Determination of the transcriptome revealed tip‐specific induction of genes encoding TCP [Teosinte Branched1 (Tb1) of maize, Cycloidea (Cyc), and Proliferating Cell Factor (Pcf)] transcription factors, RNA helicases, ribosomal proteins and proteins involved in protein folding, whilst expression of F–box domain‐containing proteins in the ubiquitin E3–SCF complex (Skp, Cullin, F‐box containing complex) was induced specifically in bases under low oxygen conditions. We ascribed the sustained elongation under hypoxia to hypoxia‐specific responses such as controlled suppression of photosystem components and induction of RNA binding/splicing functions, indicating preferential allocation of energy to cell extension.
Oxygen cost of exercise hyperpnoea is greater in women compared with men
Authors: Dominelli Paolo B. , Render Jacqueline N. , Molgat‐Seon Yannick , Foster Glen E. , Romer Lee M. , Sheel A. William 
Published: February 2015

Key points
The oxygen cost of breathing represents a significant fraction of total oxygen uptake during intense exercise.
At a given ventilation, women have a greater work of breathing compared with men, and because work is linearly related to oxygen uptake we hypothesized that their oxygen cost of breathing would also be greater.
For a given ventilation, women had a greater absolute oxygen cost of breathing, and this represented a greater fraction of total oxygen uptake.
Regardless of sex, those who developed expiratory flow limitation had a greater oxygen cost of breathing at maximal exercise.
The greater oxygen cost of breathing in women indicates that a greater fraction of total oxygen uptake (and possibly cardiac output) is directed to the respiratory muscles, which may influence blood flow distribution during exercise.
AbstractWe compared the oxygen cost of breathing () in healthy men and women over a wide range of exercise ventilations (). Eighteen subjects (nine women) completed 4 days of testing. First, a step‐wise maximal cycle exercise test was completed for the assessment of spontaneous breathing patterns. Next, subjects were familiarized with the voluntary hyperpnoea protocol used to estimate . During the final two visits, subjects mimicked multiple times (four to six) the breathing patterns associated with five or six different exercise stages. Each trial lasted 5 min, and on‐line pressure–volume and flow–volume loops were superimposed on target loops obtained during exercise to replicate the work of breathing accurately. At ∼55 l min−1 , was significantly greater in women. At maximal ventilation, the absolute was not different (P > 0.05) between the sexes, but represented a significantly greater fraction of whole‐body in women (13.8 ± 1.5 vs. 9.4 ± 1.1% ). During heavy exercise at 92 and 100% , the unit cost of was +0.7 and +1.1 ml O2 l−1 greater in women (P < 0.05). At , men and women who developed expiratory flow limitation had a significantly greater than those who did not (435 ± 44 vs. 331 ± 30 ml O2 min−1). In conclusion, women have a greater for a given , and this represents a greater fraction of whole‐body . The greater in women may have implications for the integrated physiological response to exercise.
p53-Derived Host Restriction of HIV-1 Replication by Protein Kinase R-Mediated Tat Phosphorylation and Inactivation
Authors: Yoon Cheol-Hee , Kim Sang-Yoon , Byeon Se Eun , Jeong Yideul , Lee Jinjoo , Kim Kwang Pyo , Park Jinseu , Bae Yong-Soo 
Published: February 2015

ABSTRACT

Tumor suppressor p53 has been suggested to be a host restriction factor against HIV-1 replication, but the detailed molecular mechanism has remained elusive for decades. Here, we demonstrate that p53-mediated HIV-1 suppression is attributed to double-stranded RNA (dsRNA)-dependent protein kinase (PKR)-mediated HIV-1
trans
-activator (Tat) phosphorylation and inactivation. p53 silencing significantly enhanced HIV-1 replication in infected cells. Ectopic expression of p53 suppressed Tat activity, which was rescued by PKR silencing. In addition, ectopic expression of PKR abolished Tat activity in p53
−/−
and eIF2α
CA
cells. Finally, we found that HIV-1 infection activates p53, followed by the induction and activation of PKR. PKR directly interacted with HIV-1 Tat and phosphorylates the first exon of Tat exclusively at five Ser/Thr residues (T23, T40, S46, S62, and S68), which inhibits Tat-mediated provirus transcription in three critical steps: (i) phosphorylation near the arginine-rich motif (ARM) inhibits Tat translocation into the nucleus, (ii) accumulation of Tat phosphorylation abolishes Tat–Tat-responsive region (TAR) binding, and (iii) Tat phosphorylation at T23 and/or T40 obliterates the Tat-cyclin T1 interaction. These five Ser/Thr sites on Tat were highly conserved in HIV-1 strains prevalent in Europe and the United States. Taken together, our findings indicate that p53-derived host restriction of HIV-1 replication is likely attributable, at least in part, to a noncanonical p53/PKR/Tat phosphorylation and inactivation pathway in HIV-1 infection and AIDS pathogenesis.

IMPORTANCE
HIV-1-mediated disease progression to AIDS lasts for years to decades after primary infection. Host restriction and associated viral latency have been studied for several decades. p53 has been suggested as an important host restriction factor against HIV-1 replication. However, the detailed molecular mechanism is still unclear. In the present study, we found that the p53-mediated HIV-1 restriction is attributed to a p53/PKR/Tat-inactivation pathway. HIV-1 infection activated p53, which subsequently induced PKR expression and activation. PKR directly phosphorylated Tat exclusively at five specific Ser/Thr residues, which was accompanied by significant suppression of HIV-1 replication. Accumulation of Tat phosphorylation at these sites inhibited Tat function by blocking Tat nuclear localization, Tat binding to TAR, and Tat-cyclin T1 interaction. Our findings provide a better understanding of the p53-derived host restriction mechanism against HIV-1 replication in AIDS pathogenesis and may contribute to further research focusing on the investigation of potential therapeutic targets for HIV-1.
CceR and AkgR Regulate Central Carbon and Energy Metabolism in Alphaproteobacteria
Authors: Imam Saheed , Noguera Daniel R. , Donohue Timothy J. 
Published: February 2015

ABSTRACT Many pathways of carbon and energy metabolism are conserved across the phylogeny, but the networks that regulate their expression or activity often vary considerably among organisms. In this work, we show that two previously uncharacterized transcription factors (TFs) are direct regulators of genes encoding enzymes of central carbon and energy metabolism in the alphaproteobacteriumRhodobacter sphaeroides. The LacI family member CceR (RSP_1663) directly represses genes encoding enzymes in the Entner-Doudoroff pathway, while activating those encoding the F1F0ATPase and enzymes of the tricarboxylic acid (TCA) cycle and gluconeogenesis, providing a direct transcriptional network connection between carbon and energy metabolism. We identified bases that are important for CceR DNA binding and showed that DNA binding by this TF is inhibited by 6-phosphogluconate. We also showed that the GntR family TF AkgR (RSP_0981) directly activates genes encoding several TCA cycle enzymes, and we identified conditions where its activity is increased. The properties of single and double ΔCceR and ΔAkgR mutants illustrate that these 2 TFs cooperatively regulate carbon and energy metabolism. Comparative genomic analysis indicates that CceR and AkgR orthologs are found in other alphaproteobacteria, where they are predicted to have a conserved function in regulating central carbon metabolism. Our characterization of CceR and AkgR has provided important new insight into the networks that control central carbon and energy metabolism in alphaproteobacteria that can be exploited to modify or engineer new traits in these widespread and versatile bacteria.IMPORTANCETo extract and conserve energy from nutrients, cells coordinate a set of metabolic pathways into integrated networks. Many pathways that conserve energy or interconvert metabolites are conserved across cells, but the networks regulating these processes are often highly variable. In this study, we characterize two previously unknown transcriptional regulators of carbon and energy metabolism that are conserved in alphaproteobacteria, a group of abundant, environmentally and biotechnologically important organisms. We identify the genes they regulate, the DNA sequences they recognize, the metabolite that controls the activity of one of the regulators, and conditions where they are required for growth. We provide important new insight into conserved cellular networks that can also be used to improve a variety of hosts for converting feedstock into valuable products.