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Essential Oils in Holy Basil (Ocimum tenuiflorum L.) as Influenced by Planting Dates and Harvest Times in North Alabama
Commonly known as Holy basil, Ocimum tenuiflorum (Lamiaceae), is a popular medicinal herb used for treating ailments ranging from colds to chronic diseases, such as cancers and diabetes. While Holy basil is well known in India and Southeast Asia, the plant is less known in western countries where a lack of information on cultural practices exists. In the current study, a field trial was established to determine the optimum planting date, the changes in essential oil content, and composition of O. tenuiflorum in Alabama. A total of three Holy basil accessions, PI 652056, PI 652057, and PI 288779, were planted three times at monthly intervals, beginning in April 2007. At 30, 60, and 90 days after transplanting (DATP), the aerial parts of two plants from each plot were harvested and used to determine essential oil content and composition of stems and leaves using gas chromatography-mass spectrometry. Sensory properties, yield, and composition of essential oils were affected by planting dates and harvest times. Harvesting during summer months yielded the highest amounts of oil for all three accessions. The chemotypes were identified as one high in eugenol (PI 652056), one high in β-caryophyllene (PI 652057), and a third dominated by eugenol (PI 288779) at the end of the growing period. In accession PI 652056, the level of eugenol increased with a delay in harvest time. For accession PI 652057, the level of β-caryophyllene was high at the 30-day harvest, but decreased significantly by the time of the 60-day harvest when eugenol became the dominant essential oil constituent. For the third accession (PI 288779), the essential oil was dominated by eugenol, reaching over 50% eugenol at 60 days DATP in the June planting, but the percentage of eugenol decreased towards the end of the growing season with a significant increase in (trans)-β-guaiene by 90-DATP. Of the 26 essential oil components identified in the accessions, eugenol, β-caryophyllene, E-methyl cinnamate and (trans)-β-guaiene were the most abundant constituents. The level of these essential oil constituents varied significantly in all accessions at all harvest stages. For O. tenuiflorum seedlings, the date of seeding, transplanting, and harvest DATP (plant maturity) significantly impacted total essential oil content and composition, although the level of changes within the various constituents were dependent upon the accession
Data report: X-ray fluorescence core scanning of IODP Site U1474 sediments, Natal Valley, Southwest Indian Ocean, Expedition 361
Continental-scale variation in otolith geochemistry of juvenile American shad (Alosa sapidissima)
Author Posting. Š NRC Research Press, 2008. This article is posted here by permission of NRC Research Press for personal use, not for redistribution. The definitive version was published in Canadian Journal of Fisheries and Aquatic Sciences 65 (2008): 2623-2635, doi:10.1139/F08-164.We assembled a comprehensive atlas of geochemical signatures in juvenile American shad (Alosa sapidissima) to discriminate natal river origins on a large spatial scale and at a high spatial resolution. Otoliths and (or) water samples were collected from 20 major spawning rivers from Florida to Quebec and were analyzed for elemental (Mg:Ca, Mn:Ca, Sr:Ca, and Ba:Ca) and isotope (87Sr:86Sr and δ18O) ratios. We examined correlations between water chemistry and otolith composition for five rivers where both were sampled. While Sr:Ca, Ba:Ca, 87Sr:86Sr, and δ18O values in otoliths reflected those ratios in ambient waters, Mg:Ca and Mn:Ca ratios in otoliths varied independently of water chemistry. Geochemical signatures were highly distinct among rivers, with an average classification accuracy of 93% using only those variables where otolith values were accurately predicted from water chemistry data. The study represents the largest assembled database of otolith signatures from the entire native range of a species, encompassing approximately 2700 km of coastline and 19 degrees of latitude and including all major extant spawning populations. This database will allow reliable estimates of natal origins of migrating ocean-phase American shad from the 2004 annual cohort in the future.This work was funded by National Science
Foundation (NSF) grants OCE-0215905 and OCE-0134998
to SRT and by an American Museum of Natural History
LernerâGray Grant for Marine Research and a scholarship
from SEASPACE, Inc., to BDW
High-throughput screening and classification of chemicals and their effects on neuronal gene expression using RASL-seq
We previously used RNA-seq to identify chemicals whose effects on neuronal gene expression mimicked transcriptional signatures of autism, aging, and neurodegeneration. However, this approach was costly and time consuming, which limited our study to testing a single chemical concentration on mixed sex cortical neuron cultures. Here, we adapted a targeted transcriptomic method (RASL-seq, similar to TempO-seq) to interrogate changes in expression of a set of 56 signature genes in response to a library of 350 chemicals and chemical mixtures at four concentrations in male and female mouse neuronal cultures. This enabled us to replicate and expand our previous classifications, and show that transcriptional responses were largely equivalent between sexes. Overall, we found that RASL-seq can be used to accelerate the pace at which chemicals and mixtures that transcriptionally mimic autism and other neuropsychiatric diseases can be identified, and provides a cost-effective way to quantify gene expression with a panel of marker genes
Logarithmic two-loop corrections to the Lamb shift in hydrogen
Higher order logarithmic corrections to the
hydrogen Lamb shift are calculated. The results obtained show the two-loop
contribution has a very peculiar behavior, and significantly alter the
theoretical predictions for low lying S-states.Comment: 14 pages, including 2 figures, submitted to Phys. Rev. A, updated
with minor change
âEngage the Worldâ: examining conflicts of engagement in public museums
Public engagement has become a central theme in the mission statements of many cultural institutions, and in scholarly research into museums and heritage. Engagement has emerged as the go-to-it-word for generating, improving or repairing relations between museums and society at large. But engagement is frequently an unexamined term that might embed assumptions and ignore power relationships. This article describes and examines the implications of conflicting and misleading uses of âengagementâ in relation to institutional dealings with contested questions about culture and heritage. It considers the development of an exhibition on the Dead Sea Scrolls by the Royal Ontario Museum, Toronto in 2009 within the new institutional goal to âEngage the Worldâ. The chapter analyses the motivations, processes and decisions deployed by management and staff to âEngage the Worldâ, and the degree to which the museum was able to re-think its strategies of public engagement, especially in relation to subjects,issues and publics that were more controversial in nature
Can we avoid high coupling?
It is considered good software design practice to organize source code into modules and to favour within-module connections (cohesion) over between-module connections (coupling), leading to the oft-repeated maxim "low coupling/high cohesion". Prior research into network theory and its application to software systems has found evidence that many important properties in real software systems exhibit approximately scale-free structure, including coupling; researchers have claimed that such scale-free structures are ubiquitous. This implies that high coupling must be unavoidable, statistically speaking, apparently contradicting standard ideas about software structure. We present a model that leads to the simple predictions that approximately scale-free structures ought to arise both for between-module connectivity and overall connectivity, and not as the result of poor design or optimization shortcuts. These predictions are borne out by our large-scale empirical study. Hence we conclude that high coupling is not avoidable--and that this is in fact quite reasonable
Pairing Correlations in a Generalized Hubbard Model for the Cuprates
Using numerical diagonalization of a 4x4 cluster, we calculate on-site s,
extended s and d pairing correlation functions (PCF) in an effective
generalized Hubbard model for the cuprates, with nearest-neighbor correlated
hopping and next nearest-neighbor hopping t'. The vertex contributions (VC) to
the PCF are significantly enhanced, relative to the t-t'-U model. The behavior
of the PCF and their VC, and signatures of anomalous flux quantization,
indicate superconductivity in the d-wave channel for moderate doping and in the
s-wave channel for high doping and small U.Comment: 5 pages, 5 figure
Conservation Laws in Doubly Special Relativity
Motivated by various theoretical arguments that the Planck energy (Ep - 10^19
GeV) - should herald departures from Lorentz invariance, and the possibility of
testing these expectations in the not too distant future, two so-called "Doubly
Special Relativity" theories have been suggested -- the first by
Amelino-Camelia (DSR1) and the second by Smolin and Magueijo (DSR2). These
theories contain two fundamental scales -- the speed of light and an energy
usually taken to be Ep. The symmetry group is still the Lorentz group, but in
both cases acting nonlinearly on the energy-momentum sector. Accordingly, since
energy and momentum are no longer additive quantities, finding their values for
composite systems (and hence finding the correct conservation laws) is a
nontrivial matter. Ultimately it is these possible deviations from simple
linearly realized relativistic kinematics that provide the most promising
observational signal for empirically testing these models. Various
investigations have narrowed the conservation laws down to two possibilities
per DSR theory. We derive unique exact results for the energy-momentum of
composite systems in both DSR1 and DSR2, and indicate the general strategy for
arbitrary nonlinear realizations of the Lorentz group.Comment: V2: Extensive revisions: merged with gr-qc/0205093, new author added,
references added, discussion amplified. 4 pages, revtex4; V3: Revised in
response to referee comments; no physics changes; version to appear in
Physical Review
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