522 research outputs found
Coupling bioturbation activity to metal (Fe and Mn) profiles in situ
This work was supported by a University of Aberdeen 6th century scholarship (awarded to L. T.), CEFAS Lowestoft (DP204), NERC NFSD support (08/02) and a SAMS research bursary (awarded to L. T)Peer reviewedPublisher PD
Parasitic nematode Meloidogyne incognita interactions with different Capsicum annum cultivars reveal the chemical constituents modulating root herbivory
Open Access Journal; Published online: 06 June 2017Plant volatile signatures are often used as cues by herbivores to locate their preferred hosts. Here, we report on the volatile organic compounds used by the subterranean root-knot nematode (RKN) Meloidogyne incognita for host location. We compared responses of infective second stage juveniles (J2s) to root volatiles of three cultivars and one accession of the solanaceous plant, Capsicum annum against moist sand in dual choice assays. J2s were more attracted to the three cultivars than to the accession, relative to controls. GC/MS analysis of the volatiles identified common constituents in each plant, five of which were identified as α-pinene, limonene, 2-methoxy-3-(1-methylpropyl)-pyrazine, methyl salicylate and tridecane. We additionally identified thymol as being specific to the accession. In dose-response assays, a blend of the five components elicited positive chemotaxis (71â88%), whereas individual components elicited varying responses; Methyl salicylate (MeSA) elicited the highest positive chemotaxis (70â80%), α-pinene, limonene and tridecane were intermediate (54â60%), and 2-methoxy- 3-(1-methylpropyl)-pyrazine the lowest (49â55%). In contrast, thymol alone or thymol combined with either the preferred natural plant root volatiles or the five-component synthetic blend induced negative chemotaxis. Our results provide insights into RKN-host plant interactions, creating new opportunities for plant breeding programmes towards management of RKNs
- shell gap reduction in neutron-rich systems and cross-shell excitations in O
Excited states in O were populated in the reaction
Be(C,) at Florida State University. Charged particles
were detected with a particle telescope consisting of 4 annularly segmented Si
surface barrier detectors and radiation was detected with the FSU
detector array. Five new states were observed below 6 MeV from the
- and -- coincidence data. Shell model
calculations suggest that most of the newly observed states are core-excited
1p-1h excitations across the shell gap. Comparisons between
experimental data and calculations for the neutron-rich O and F isotopes imply
a steady reduction of the - shell gap as neutrons are added
Aspirin and extended-release dipyridamole versus clopidogrel for recurrent stroke
Background
Recurrent stroke is a frequent, disabling event after ischemic stroke. This study compared
the efficacy and safety of two antiplatelet regimens â aspirin plus extendedrelease
dipyridamole (ASAâERDP) versus clopidogrel.
Methods
In this double-blind, 2-by-2 factorial trial, we randomly assigned patients to receive
25 mg of aspirin plus 200 mg of extended-release dipyridamole twice daily or to receive
75 mg of clopidogrel daily. The primary outcome was first recurrence of stroke.
The secondary outcome was a composite of stroke, myocardial infarction, or death
from vascular causes. Sequential statistical testing of noninferiority (margin of 1.075),
followed by superiority testing, was planned.
Results
A total of 20,332 patients were followed for a mean of 2.5 years. Recurrent stroke
occurred in 916 patients (9.0%) receiving ASAâERDP and in 898 patients (8.8%) receiving
clopidogrel (hazard ratio, 1.01; 95% confidence interval [CI], 0.92 to 1.11). The
secondary outcome occurred in 1333 patients (13.1%) in each group (hazard ratio for
ASAâERDP, 0.99; 95% CI, 0.92 to 1.07). There were more major hemorrhagic events
among ASAâERDP recipients (419 [4.1%]) than among clopidogrel recipients (365
[3.6%]) (hazard ratio, 1.15; 95% CI, 1.00 to 1.32), including intracranial hemorrhage
(hazard ratio, 1.42; 95% CI, 1.11 to 1.83). The net risk of recurrent stroke or major
hemorrhagic event was similar in the two groups (1194 ASAâERDP recipients [11.7%],
vs. 1156 clopidogrel recipients [11.4%]; hazard ratio, 1.03; 95% CI, 0.95 to 1.11).
Conclusions
The trial did not meet the predefined criteria for noninferiority but showed similar rates
of recurrent stroke with ASAâERDP and with clopidogrel. There is no evidence that either
of the two treatments was superior to the other in the prevention of recurrent
stroke. (ClinicalTrials.gov number, NCT00153062.
A Forward Genetic Screen Reveals Novel Independent Regulators of Ulbp1, an Activating Ligand for Natural Killer Cells
Recognition and elimination of tumor cells by the immune system is crucial for limiting tumor growth. Natural killer (NK) cells become activated when the receptor NKG2D is engaged by ligands that are frequently upregulated in primary tumors and on cancer cell lines. However, the molecular mechanisms driving NKG2D ligand expression on tumor cells are not well defined. Using a forward genetic screen in a tumor-derived human cell line, we identified several novel factors supporting expression of the NKG2D ligand ULBP1. Our results show stepwise contributions of independent pathways working at multiple stages of ULBP1 biogenesis. Deeper investigation of selected hits from the screen showed that the transcription factor ATF4 drives ULBP1 gene expression in cancer cell lines, while the RNA-binding protein RBM4 supports ULBP1 expression by suppressing a novel alternatively spliced isoform of ULBP1 mRNA. These findings offer insight into the stress pathways that alert the immune system to danger
Tracking the tempo of a continental margin arc: Insights from a forearc succession in West Antarctica
The Fossil Bluff Group of eastern Alexander Island records the exceptional preservation of more than 8 km of Mesozoic sedimentary rocks deposited into an accretionary forearc basin that developed unconformably above a late Paleozoic accretionary complex, and in proximity to a continental margin arc during a prolonged phase of enhanced magmatism. Through the Mesozoic, the Fossil Bluff Group evolved from a trench-slope environment to a forearc basin sourced from the continental margin arc. During this period, the Antarctic Peninsulaâs convergent margin was characterized by episodes of magmatic flare-ups that developed during tectonic compression, crustal thickening, extension, and uplift. U-Pb and Lu-Hf detrital zircon data are used to determine the provenance of the forearc succession and as a monitor of arc magmatic tempos during the late Mesozoic. The magmatic record in the adjacent arc is poorly preserved or partially absent, but the sedimentary record of the forearc basin preserves a largely uninterrupted record of arc magmatism that can be studied with detrital zircon geochronology and geochemistry. The basal succession of the Fossil Bluff Group is sourced from the adjacent accretionary complex, but thereafter it is strongly controlled by the proximal arc in western Palmer Land and is characterized by a mixed arc/recycled signature during episodes of renewed sedimentation. However, the main phases of deposition during the Early Jurassic (ca. 180 Ma), Early Cretaceous (141â131 Ma), and mid-Cretaceous (125â102 Ma) are dominated by arc-only sources. The Lu-Hf isotopic record supports a transition from convergence to extension and a return to convergence during the Mesozoic, which is consistent with accretionary orogens from elsewhere along the West Gondwanan margin. The provenance record during the depositional history of the basin points overwhelmingly to an autochthonous origin; as such, models for parts of the western province of the Antarctic Peninsula being allochthonous are unsupported
Managing Coastal Resources In The 21St Century
Coastal ecosystems are increasingly dominated by humans. Consequently, the human dimensions of sustainability science have become an integral part of emerging coastal governance and management practices. But if we are to avoid the harsh lessons of land management, coastal decision makers must recognize that humans are one of the more coastally dependent species in the biosphere. Management responses must therefore confront both the temporal urgency and the very real compromises and sacrifices that will be necessary to achieve a sustainable coastal ecosystem, one that is economically feasible, socially just, and ecologically sound
Changes in Pharmacy Students After Experiencing Interprofessional Education Activities
Background: Interprofessional education (IPE) has become increasingly important among healthcare professionals. The purpose of this study was to assess the impact of IPE experiences on pharmacy studentsâ perceived level of comfort with and level of reliability regarding other healthcare professionals. Methods and Findings: A survey of third- and fourth-year pharmacy students (N = 190) was analyzed using descriptive statistics and bivariate analyses to address the study objectives. Students experienced a significant increase in their level of comfort with questioning other professions after IPE (pre IPE: 5.45 ± 2.24 and post IPE: 7.22 ± 1.62, p<0.01) and being questioned by other professions (pre IPE: 5.39 ± 2.24 and post IPE: 7.04 ± 1.68, p<0.01). Students also experienced a significant increase in the perceived reliability and accuracy of information from nurses after IPE (pre IPE: 5.91 ± 1.82 and post IPE: 6.41 ± 1.62, p = 0.01). Conclusions: Pharmacy students who experienced any IPE perceived themselves as more comfortable with questioning and being questioned by other healthcare professionals than students without IPE. Additional research is needed to more clearly define the benefits of IPE and how it should be designed
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