178,738 research outputs found
Aquaculture, fisheries, poverty and food security
Fisheries and aquaculture play important roles in providing food and income in many developing countries, either as a stand-alone activity or in association with crop agriculture and livestock rearing. The aim of this paper is to identify how these contributions of fisheries and aquaculture to poverty reduction and food security can be enhanced while also addressing the need for a sustainability transition in over-exploited and over-capitalized capture fisheries, and for improved environmental performance and distributive justice in a rapidly growing aquaculture sector. The focus of the paper is on the poverty and food security concerns of developing countries, with an emphasis on the least developed. The emphasis is on food security rather than poverty reduction policies and strategies, although the two are of course related. The food security agenda is very much to the fore at present; fish prices rose along with other food prices in 2007-8 and as fish provide important nutritional benefits to the poor, food security has become a primary concern for sector policy
Dark matter, singlet extensions of the nuMSM, and symmetries
We consider an extension of the nuMSM in which sterile neutrino masses
originate from the VEV of a Higgs singlet phi and dark matter is produced
through the decays of phi rather than through active-sterile neutrino mixing.
This model, which we refer to as the nuNMSM, can readily satisfy or escape the
constraints on warm dark matter from the Lyman-alpha forest and other small
scale structure. However, it requires a particular hierarchy of Majorana masses
and Yukawa couplings without an obvious origin. We show that the hierarchical
parameters of the nuNMSM can arise from symmetries broken at or near the Planck
scale for two specific examples of this model: one in which phi helps stabilize
the electroweak vacuum through a scalar threshold effect and one in which phi
is a light inflaton. Both examples require a complex phi and have several
experimental signatures that are distinct from the nuMSM. These signatures
include additional dark radiation that is relativistic at both primordial
nucleosynthesis and CMB decoupling and, for the former, a large invisible
branching ratio of the Higgs.Comment: 22 pages, 3 tables. v2: Discussion clarified and references added.
Matches published versio
The Effect of Print Angulation on the Accuracy and Precision of 3D-Printed Orthodontic Retainers
Purpose: The aims of this study were: 1) to compare the accuracy and precision of 3-
dimensional (3D) printed retainers at various angulations, 2) to evaluate the effect of angulation
on printing time and the amount of resin consumed.
Methods: Using a stereolithography (SLA) 3D printer, a total of 60 clear retainers were printed at five angulations (n=12, each): 15, 30, 45, 60, and 90 degrees. Six retainers were printed each cycle at a random order for all print angulations as print 1 and print 2. Digital images of the original and printed retainers were superimposed. Discrepancies on eight landmarks were measured by two independent examiners. 0.25 mm was set as the clinically acceptable threshold to determine the accuracy of the retainers.
Results: Deviations ranged from 0.074 mm to 0.225 mm from the reference retainer at the cusp tips and incisal edges at all angulations, falling within the threshold of clinical acceptance. Smooth surfaces ranged from 0.263 mm to 0.480 mm, falling beyond the level of clinical acceptance. Printing at 15 degrees was estimated to be the most time-efficient, while printing at 45 degrees was estimated to be the most cost-effective.
Conclusions: 3D-printed retainers, using an SLA printer, were found to be accurate within 0.25 mm at all print angulations at the cusp tips and incisal edges when compared to the reference digital file. Smooth facial surfaces fell beyond of the level of clinical acceptability. Printing at 15 degrees was estimated to be the most time-efficient, while printing at 45 degrees was estimated to be the most cost-effective
Addressing Cultural Barriers in Australia’s Acute Care System: Problems the United States Can Learn From
Breaking the Mold: Four Asian American women define beauty, detail identity, and deconstruct stereotypes
The experiences of four women reveal how notions of outer beauty touch ideas of personal ethnic identity, racism, media-imposed pressure, and social stereotypes; shaping the lives of Chinese, Chinese American, and Asian American women
A Pragmatic Look at Schopenhauer’s Pessimism
Schopenhauer’s pessimistic philosophy is a depressing read. He writes many
pages about how suffering is the norm, and any happiness we feel is merely a
temporary alleviation of suffering. Even so, his account of suffering rings true
to many readers. What are we to do with our lives if Schopenhauer is right,
and we are doomed to suffer? In this paper, I use William James’ pragmatic
method to find practical implications of Schopenhauer’s pessimism. I provide
a model for how we are to live our lives in a suffering world, a model that
provides means to reduce suffering
Consciousness Duplication And Our Capacity To Learn From Literary Fictions
Many of us share a strong intuition that fictional literature possesses cognitive value in the sense that it has the capacity to expand and/or clarify our knowledge or understanding of the world. If we agree that we learn something when we read and discuss certain texts, we may nevertheless find the form this learning takes to be anything but obvious
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