585 research outputs found
Organic Lawn Care Case Studies on Home Turf
The consistent growth in certified organic farming and demand for organic foods has fostered a companion movement towards employing organic growing methods for land care. With the objective of evaluating the agronomic potential for organic land care, I conducted a case study on my property in Monroe, NJ following land disturbance from construction. After the site was remediated with deep tillage to alleviate compaction and amended with compost and limestone based on soil tests it was seeded in September 2009 with a mix of modern turf type Kentucky bluegrass cultivars. Once established, this lawn was attractive, competitive against most weeds, and performed well over the following six years under organic management. This lawn was mowed frequently with the clippings always returned so as to recycle nutrients in place. It remained attractive without fertilizer input. In 2014, another organic lawn study was established at my farm in Ringoes, NJ to evaluate several organic fertilizers. Observations from this second case study indicated that soil test P was a key factor for turf establishment. Experience with the organic lawn in Ringoes, when contrasted to the results in Monroe, suggested that rapid germination and establishment of a dense turf stand is very important to preventing weeds during establishment
An Investigation of the Labor Market Earnings of Panamanian Males: Evaluating Sources of Inequality
The strategic use of patents in standardization in relation to US, European and Chinese competition law
Technologies embedded in standards are most often protected by patents. This research shows that competition law concerns will be raised as soon as the standardization process is manipulated to enable patent holders to gain unfair competitive advantages. Strategic patenting has become common practice in the telecommunications industry. Substantial patent portfolios are used as “weapons of mass destruction” to fend off infringement cases by competitors. This study argues that patent pools are a possible solution to the aforementioned problems in the US, EU and China. Chinese firms may benefit from Western technology in standards that are cooperatively developed. Western companies would appreciate the increased legal certainty and the possibility of outsourcing more sophisticated forms of manufacturing to Chinese firms. Patent pools are a good alternative for the Chinese government and businesses to participate more in standards. A patent pool can facilitate a smoother and more efficient technology transfer for foreign companies in China, which would benefit all the relevant stakeholders, including the Chinese government
Making Sense of the Epigenome Using Data Integration Approaches
Epigenetic research involves examining the mitotically heritable processes that regulate gene expression, independent of changes in the DNA sequence. Recent technical advances such as whole-genome bisulfite sequencing and affordable epigenomic array-based technologies, allow researchers to measure epigenetic profiles of large cohorts at a genome-wide level, generating comprehensive high-dimensional datasets that may contain important information for disease development and treatment opportunities. The epigenomic profile for a certain disease is often a result of the complex interplay between multiple genetic and environmental factors, which poses an enormous challenge to visualize and interpret these data. Furthermore, due to the dynamic nature of the epigenome, it is critical to determine causal relationships from the many correlated associations. In this review we provide an overview of recent data analysis approaches to integrate various omics layers to understand epigenetic mechanisms of complex diseases, such as obesity and cancer. We discuss the following topics: (i) advantages and limitations of major epigenetic profiling techniques, (ii) resources for standardization, annotation and harmonization of epigenetic data, and (iii) statistical methods and machine learning methods for establishing data-driven hypotheses of key regulatory mechanisms. Finally, we discuss the future directions for data integration that shall facilitate the discovery of epigenetic-based biomarkers and therapies.Peer reviewe
Evidence for a Black Hole and Accretion Disk in the LINER NGC 4203
We present spectroscopic observations from the Hubble Space Telescope that
reveal for the first time the presence of a broad pedestal of Balmer-line
emission in the LINER galaxy NGC 4203. The emission-line profile is suggestive
of a relativistic accretion disk, and is reminiscent of double-peaked transient
Balmer emission observed in a handful of other LINERs. The very broad line
emission thus constitutes clear qualitative evidence for a black hole, and
spatially resolved narrow-line emission in NGC 4203 can be used to constrain
its mass, with M_BH less than 6 x 10^6 solar masses at 99.7% confidence. This
value implies a ratio of black-hole mass to bulge mass of less than
approximately 7 x 10^-4 in NGC 4203, which is less by a factor of ~3 - 9 than
the mean ratio obtained for other galaxies. The availability of an independent
constraint on central black-hole mass makes NGC4203 an important testbed for
probing the physics of weak active galactic nuclei. Assuming M_BH near the
detection limit, the ratio of observed luminosity to the Eddington luminosity
is approximately 10^-4. This value is consistent with advection-dominated
accretion, and hence with scenarios in which an ion torus irradiates an outer
accretion disk that produces the observed double-peaked line emission.
Follow-up observations will make it possible to improve the black-hole mass
estimate and study variability in the nuclear emission.Comment: 10 pages (LaTeX, AASTeX v4.0), 2 postscript figures, accepted for
publication in The Astrophysical Journal Letter
F-theory Compactifications for Supersymmetric GUTs
We construct a family of elliptically fibered Calabi-Yau four-folds Y_4 for
F-theory compactifications that realize SU(5) GUTs in the low-energy limit. The
three-fold base X_3 of these fibrations is almost Fano and satisfies the
topological criteria required to ensure that the U(1)_Y gauge boson remains
massless, while allowing a decoupling of GUT and Planck scale physics. We study
generic features of these models and the ability to engineer three chiral
generations of MSSM matter. Finally, we demonstrate that it is relatively easy
to implement the topological conditions required to reproduce certain
successful features of local F-theory models, such as the emergence of flavor
hierarchies.Comment: 55 pages, 10 figure
Barriers to the management of Heart Failure in Ontario Long-Term Care Homes: an Interprofessional Care perspective
Background: With population aging, the prevalence of heart failure (HF) is risingin long-term care (LTC) homes. Given this burden, there is an urgent need to establish effective HF management programs.Methods and Findings: To understand what barriers would need to be addressed to develop such a program, we conducted a series of consultations among various LTC staff, as well as residents and their family caregivers. This article uses data obtained from the consultations to describe the interprofessional (IP) barriers that exist among the various LTC staff roles. Consultation methods included a Delphi survey followed by focus group interviews of LTC staff, and then personal interviews with LTC residents with HF and their family caregivers. Data were interpreted using an IP care framework in which interpersonal relationships among LTC staff provide the most direct influence on collaborative resident-centred practice, within the broader context of conditions within the LTC home, which in turn are housed in the broader context of systemic determinants.Conclusion: Across all data sets, the most consistently mentioned determinant was communication between the resident and the healthcare team, between different healthcare providers, between shifts, between medical specialists, and between the long-term care home and the hospital
STIS ultraviolet/optical spectroscopy of `warm' ultraluminous infrared galaxies
(Abridged) We present high spatial resolution ultraviolet and optical
spectroscopy, obtained using the Space Telescope Imaging Spectrograph on board
the Hubble Space Telescope, of nuclear structures within four `warm'
Ultraluminous Infrared Galaxies (ULIRGs). We find an AGN in at least three, and
probably all four of our sample, hosted in a compact, optically luminous
`knot'. In three cases these knots were previously identified as a putative AGN
nucleus from multiband optical imaging. Three of the sample also harbor a
starburst in one or more knots, suggesting that the optically luminous knots
seen in local ULIRGs are the most likely sites of the dust-shrouded starburst
and AGN activity that power the infrared emission. The four AGN have a diverse
range of properties; two are classical narrow line AGN, one shows both broad
and narrow lines and evidence for lines of sight from the narrow through to the
broad line regions, and one is plausibly a FeLoBAL AGN. The probable presence
in one object of an FeLoBAL AGN, which are extremely rare in the QSO
population, supports the idea that LoBAL AGN may be youthful systems shrouded
in gas and dust rather than AGN viewed along a certain line of sight. The three
starbursts for which detailed constraints are possible show a smaller range in
properties; all three bursts are young with two having ages of ~4Myr and the
third having an age of 20Myr, suggesting that ULIRGs undergo several bursts of
star formation during their lifetimes. None of the starbursts show evidence for
Initial Mass Function slopes steeper than about 3.3. The metallicities of the
knots for which metallicities can be derived are all at least 1.5 times the
Solar value. The properties of one further starburst knot are consistent with
it being the forming core of an elliptical galaxy.Comment: ApJ, accepte
ROSAT PSPC observations of nearby spiral galaxies - II. Statistical properties
We present a statistical analysis of the largest X-ray survey of nearby
spiral galaxies in which diffuse emission has been separated from discrete
source contributions. Regression and rank-order correlation analyses are used
to compare X-ray properties such as total, source and diffuse luminosities, and
diffuse emission temperature, with a variety of physical and multi-wavelength
properties, such as galaxy mass, type and activity, and optical and infrared
luminosity. The results are discussed in terms of the way in which hot gas and
discrete X-ray sources scale with the mass and activity of galaxies, and with
the star formation rate. We find that the X-ray properties of starburst
galaxies are dependent primarily on their star-forming activity, whilst for
more quiescent galaxies, galaxy mass is the more important parameter. One of
the most intriguing results is the tight linear scaling between far-infrared
and diffuse X-ray luminosity across the sample, even though the hot gas changes
from a hydrostatic corona to a free wind across the activity range sampled
here.Comment: 13 pages, latex file, 18 postscript figures, to appear in MNRA
LINER/H II "Transition" Nuclei and the Nature of NGC 4569
Motivated by the discovery of young, massive stars in the nuclei of some
LINER/H II ``transition'' nuclei such as NGC 4569, we have computed
photoionization models to determine whether some of these objects may be
powered solely by young star clusters rather than by accretion-powered active
nuclei. The models were calculated with the photoionization code CLOUDY, using
evolving starburst continua generated by the the STARBURST99 code of Leitherer
et al. (1999). We find that the models are able to reproduce the emission-line
spectra of transition nuclei, but only for instantaneous bursts of solar or
higher metallicity, and only for ages of ~3-5 Myr, the period when the
extreme-ultraviolet continuum is dominated by emission from Wolf-Rayet stars.
For clusters younger than 3 Myr or older than 6 Myr, and for models with a
constant star-formation rate, the softer ionizing continuum results in an
emission spectrum more typical of H II regions. This model predicts that
Wolf-Rayet emission features should appear in the spectra of transition nuclei.
While such features have not generally been detected to date, they could be
revealed in observations having higher spatial resolution. Demographic
arguments suggest that this starburst model may not apply to the majority of
transition nuclei, particularly those in early-type host galaxies, but it could
account for some members of the transition class in hosts of type Sa and later.
The starburst models during the Wolf-Rayet-dominated phase can also reproduce
the narrow-line spectra of some LINERs, but only under conditions of
above-solar metallicity and only if high-density gas is present (n_e >~ 10^5
cm^{-3}). This scenario could be applicable to some ``Type 2'' LINERs which do
not show any clear signs of nonstellar activity.Comment: To appear in PASP. 22 pages, includes 9 figures, uses AASTeX v5.
- …