3,399 research outputs found

    Planting date effects on the germinability and seedling vigour of Abutilon theophrasti (Malvaceae) seeds

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    Abutilon theophrasti (Malvaceae) is a troublesome annual weed in many maize and soybean cropping systems of Canada and the United States. Seeds of A. theophrasti exhibit physical dormancy. Differences in the growing environment of parent plants may influence the germinability of seeds and vigour of seedlings produced by this species because of variation in resource allocation to seed development. Thus, the germinability of seeds and subsequent seedling vigour were examined for A. theophrasti plants grown in monoculture at a density of 4.2 plants m-2 under varying natural photoperiods in central New York State. Treatments were established by transplanting A. theophrasti seedlings on three dates: 15 May, 4 June, and 30 June 2000, which correspond to peak photoperiods of 15, 14, and 13 hours, respectively. Seeds produced under the shorter photoperiod (13 h) weighed, on average, 1.5 mg less than seeds produced under the longer photoperiod (15 h). Contrary to expectations, seeds of A. theophrasti that matured under shorter photoperiods had lower germinability (80%) than seeds produced under longer photoperiods (98%). Early radicle growth, a measure of seedling vigour, did not differ between the photoperiod treatments. Environmental conditions other than photoperiod (i.e. water availability) prevailing during the 2000-growing season may have influenced seed coat thickness and consequently affected the germinability of seeds.L’Abutilon theophrasti (Malvaceae) est une mauvaise herbe annuelle qui gêne la production du maïs et du soja dans plusieurs systèmes de culture du Canada et des États-Unis. Les graines de l’A. theophrasti possèdent une dormance physique. Des différences de l’environnement dans lequel croissent les plantes mères peuvent influencer la germination des graines et la vitalité des plantules de cette espèce à cause de variations dans l’affectation des ressources avant que les graines soient pleinement développées. Ainsi, la germination des graines et la vitalité des plantules qui en sont issues ont été étudiées pour l’A. theophrasti en monoculture à une densité de 4,2 plantes m-2 sous diverses photopériodes naturelles du centre de l’État de New York. Les traitements ont débuté par la plantation de plantules de l’A. theophrasti à trois dates, 15 mai, 6 juin et 30 juin 2000, qui correspondent respectivement à des photopériodes maximales de 15, 14 et 13 heures. Les graines produites avec la photopériode la plus courte (13 h) pesaient en moyenne 1,5 mg de moins que les graines produites avec les plus longues photopériodes (15 h). Contrairement à ce qui était prévu, les graines de l’A. theophrasti qui se sont formées lors des photopériodes les plus courtes avaient une germination plus faible (80 %) que les graines formées lors des photopériodes les plus longues (98 %). La croissance précoce de la radicule, une mesure de la vitalité des plantules, est restée la même pour les différentes photopériodes. Les conditions environnementales autres que la photopériode (c.-à-d. la disponibilité en eau) qui régnaient au cours de la saison de croissance de 2000 peuvent avoir influencé l’épaisseur du tégument et avoir ainsi eu un effet sur la germination des graines

    Handbook for the Post-Earthquake Safety Evaluation of Bridges and Roads

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    It is acknowledged that the most damaging earthquake within the state took place on September 27, 1909 near the Illinois border between Vincennes and Terre Haute. Both nonstructural and structural damage occurred to the buildings in this area, and it was felt strongly in the southwest of Indiana including Indianapolis. Unfortunately, due to the long recurrence interval of strong earthquakes in Mid-America, a large inventory of structures has accumulated without explicit consideration of seismic resistance. Highway bridges are a significant component of this inventory. The seismic vulnerability of highway bridges constructed within the state, especially in southwestern portion of Indiana, presents a problem of serious consequences. The main purpose of this handbook is to provide INDOT personnel of various backgrounds with a rapid and effective methodology for the post-earthquake safety inspection of bridges and roads in Indiana. This methodology is intended to promote and maintain the uniformity of the inspection as much as possible while assessing and rating bridge and road damage. This handbook contains the material necessary for a systematic safety evaluation of bridge structures and roads for a wide range of INDOT personnel. In the handbook, the necessary material is arranged according to two inspection levels. Level 1 inspection consists of the rapid visual evaluation of the bridges and roads in the affected area to establish obviously unsafe structures and roads. The Level 1 section of the handbook is intended for INDOT personnel with a broad range of backgrounds. Level 2 inspection consists of a more in-depth safety evaluation of bridges and roads, as well as temporary repair and long-term monitoring techniques. This segment is designed specifically for INDOT engineers. The Level 2 inspection team will be expected to make a more detailed structural and geotechnical post-earthquake condition assessment of the bridge. The organization and the management of the post-earthquake inspections are under the jurisdiction of INDOT, unless declared a State Disaster by the Governor and taken over by SEMA, and it is outside the scope of this handbook

    Clinical Research in Pneumonia: Role of Artificial Intelligence

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    Measuring Concurrency Attitudes: Development and Validation of a Vignette-Based Scale

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    Concurrent sexual partnerships (partnerships that overlap in time) may contribute to higher rates of HIV transmission in African Americans. Attitudes toward a behavior constitute an important component of most models of health-related behavior and behavioral change. We have developed a scale, employing realistic vignettes that appear to reliably measure attitudes about concurrency in young African American adults

    SN 2007gr: a Normal Type Ic Supernova with a Mildly Relativistic Radio Jet?

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    A nearby type Ic supernova, SN 2007gr was observed with the EVN in two epochs 60 days apart (second observation also included the Green Bank Telescope). In both cases one of the EVN stations was the Westerbork Synthesis Radio Telescope (WSRT), which recorded the observational data not only in the VLBI mode, but also in its normal interferometric mode. Thus it provided an important reference observation. In the first epoch the fluxes measured by the VLBI network and the WSRT alone match well. However in the second epoch the peak brightness observed in the VLBI experiment is much lower than the total flux recorded by the WSRT. There could be multiple reasons for this discrepancy: a resolution effect, coherence losses in VLBI, or extended emission contaminating the WSRT measurement. With new WSRT observations we costrain the level of background emission and find that there is still a difference between the corrected total flux density and the VLBI peak brightness. If one assumes that this is dominated by resolution, this would correspond to an average apparent expansion speed of ~0.4c

    The Community-Acquired Pneumonia Organization (CAPO) Cloud-Based Research Platform (the CAPO-Cloud): Facilitating Data Sharing in Clinical Research

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    Background: Pneumonia is a costly and deadly respiratory disease that afflicts millions every year. Advances in pneumonia care require significant research investment and collaboration among pneumonia investigators. Despite the importance of data sharing for clinical research it remains difficult to share datasets with old and new investigators. We present CAPOCloud, a web-based pneumonia research platform intended to facilitate data sharing and make data more accessible to new investigators. Methods: We establish the first two use cases for CAPOCloud to be the automatic subsetting and constraining of the CAPO database and the automatic summarization of the database in aggregate. We use the REDCap data capture software and the R programming language to facilitate these use cases. Results: CAPOCloud allows CAPO investigators to access the CAPO clinical database and explore subsets of the data including demographics, comorbidities, and geographic regions. It also allows them to summarize these subsets or the entire CAPO database in aggregate while preserving privacy restrictions. Discussion: CAPOCloud demonstrates the viability of a research platform combining data capture, data quality, hypothesis generation, data exploration and data sharing in one interface. Future use cases for the software include automated univariate hypothesis testing, automated bivariate hypothesis testing, and principal component analysis

    Human Pleural Fluid Elicits Pyruvate and Phenylalanine Metabolism in Acinetobacter baumannii to Enhance Cytotoxicity and Immune Evasion

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    The CCAAT box-harboring proteins represent a family of heterotrimeric transcription factors which is highly conserved in eukaryotes. In fungi, one of the particularly important homologs of this family is the Hap complex that separates the DNA-binding domain from the activation domain and imposes essential impacts on regulation of a wide range of cellular functions. So far, a comprehensive summary of this complex has been described in filamentous fungi but not in the yeast. In this review, we summarize a number of studies related to the structure and assembly mode of the Hap complex in a list of representative yeasts. Furthermore, we emphasize recent advances in understanding the regulatory functions of this complex, with a special focus on its role in regulating respiration, production of reactive oxygen species (ROS) and iron homeostasis.Fil: Nyah, Rodman. California State University; Estados UnidosFil: Martinez, Jasmine. California State University; Estados UnidosFil: Fung, Sammie. California State University; Estados UnidosFil: Nakanouchi, Jun. California State University; Estados UnidosFil: Myers, Amber L.. California State University; Estados UnidosFil: Harris, Caitlin M.. California State University; Estados UnidosFil: Dang, Emily. California State University; Estados UnidosFil: Fernandez, Jennifer. California State University; Estados UnidosFil: Liu, Christine. California State University; Estados UnidosFil: Mendoza, Anthony M.. California State University; Estados UnidosFil: Jimenez, VerĂłnica. California State University; Estados UnidosFil: Nikolaidis, Nikolas. California State University; Estados UnidosFil: Brennan, Catherine A.. California State University; Estados UnidosFil: Bonomo, Robert A.. Louis Stokes Cleveland Department of Veterans Affairs Medical Cente; Estados Unidos. Center for Antimicrobial Resistance and Epidemiology; Estados Unidos. Case Western Reserve University School of Medicine; Estados UnidosFil: Sieira, Rodrigo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Instituto de Investigaciones BioquĂ­micas de Buenos Aires. FundaciĂłn Instituto Leloir. Instituto de Investigaciones BioquĂ­micas de Buenos Aires; ArgentinaFil: Ramirez, Maria Soledad. California State University; Estados Unido

    Allergens and Irritants Transcriptionally Upregulate CD80 Gene Expression in Human Keratinocytes

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    The human CD80 costimulatory molecule is an important signal between professional antigen-presenting cells and T helper cells. The immunobiology of CD80 expression by keratinocytes, especially during allergic and irritant contact dermatitis, however, is less well understood. CD80 cell surface expression and gene transcription by keratinocytes was increased when keratinocytes were exposed to certain allergens (chemicals that induce inflammation via hapten-specific T cells) and irritants (chemicals that are toxic to epidermal cells). Therefore, the human CD80 promoter was cloned and luciferase reporter constructs containing various promoter fragments were engineered. Promoter mapping of these CD80 constructs in transiently transfected keratinocytes showed that a construct containing the proximal 231 bp immediately upstream of the transcription start site of the CD80 promoter was most active in keratinocytes and was inducible to a level ranging from 2- to 10-fold higher in keratinocytes treated with certain allergens and irritants, compared with untreated keratinocytes. This pattern of promoter fragment activity in keratinocytes is identical to that found in professional antigen-presenting cells. This is the first demonstration that the CD80 promoter is active in keratinocytes and that this activity is further increased in keratinocytes treated with certain allergens and irritants. These data suggest that allergens and irritants may, in part, break peripheral tolerance by their direct effects on keratinocyte costimulatory molecule expression, thereby facilitating interactions with epidermotropic T helper cells via the CD80–CD28 or CTLA-4 pathways
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