7,954 research outputs found
Three computer codes to read, plot and tabulate operational test-site recorded solar data
Computer programs used to process data that will be used in the evaluation of collector efficiency and solar system performance are described. The program, TAPFIL, reads data from an IBM 360 tape containing information (insolation, flowrates, temperatures, etc.) from 48 operational solar heating and cooling test sites. Two other programs, CHPLOT and WRTCNL, plot and tabulate the data from the direct access, unformatted TAPFIL file. The methodology of the programs, their inputs, and their outputs are described
de Sitter geodesics: reappraising the notion of motion
The de Sitter spacetime is transitive under a combination of translations and
proper conformal transformations. Its usual family of geodesics, however, does
not take into account this property. As a consequence, there are points in de
Sitter spacetime which cannot be joined to each other by any one of these
geodesics. By taking into account the appropriate transitivity properties in
the variational principle, a new family of maximizing trajectories is obtained,
whose members are able to connect any two points of the de Sitter spacetime.
These geodesics introduce a new notion of motion, given by a combination of
translations and proper conformal transformations, which may possibly become
important at very-high energies, where conformal symmetry plays a significant
role.Comment: 9 pages. V2: Presentation changes aiming at clarifying the text;
version accepted for publication in Gen. Rel. Gra
Developing teachers' competences for designing inclusive learning experiences
Inclusive education, namely the process of providing all learners with equal educational opportunities, is a major challenge for many educational systems worldwide. In order to address this issue, a widely used framework has been developed, namely the Universal Design for Learning (UDL), which aims to provide specific educational design guidelines to ensure accessibility of all learner types to the learning environment. On the other hand, nowadays teachers are provided with ample opportunities for freely accessing a wide number of Open Educational Resources (OERs) that are available through existing OER initiatives. Within this context and following the UDL principles, teachers are expected to be able to select and transform and/or augment, OERs to fit their learners' diverse needs towards delivering inclusive learning experiences. This calls for developing specific teachers' competences that are aligned with existing competence frameworks such as the Competence Framework for Inclusive Teachers (CFIT) towards effectively engaging them in the aforementioned process. To this end, the scope of this paper is to present the design, implementation and evaluation of a teacher professional development program (PDP) aligned with CFIT for designing inclusive OERs by applying the UDL principles. The evaluation results of the teacher PDP demonstrated its added value for developing teachers' competences towards designing inclusive learning experiences for their students
Land Market Valuation of Groundwater
We estimate irrigation premiums and implicit marginal valuations of water in-storage using parcel-level transaction data for land sales in the Kansas portion of the High Plains Aquifer. We find that agricultural land values are 53% higher for irrigated parcels than non-irrigated parcels on average and that the irrigation premium has increased at an average rate of 1.0 percentage points per year over the sample period (1988–2015). Spatial heterogeneity in irrigation premiums is explained by differences in saturated thickness of the aquifer. Water in-storage is capitalized into land prices at average marginal values ranging from 15.86/acre-ft
I can see CRISPR now, even when phage are gone: a view on alternative CRISPR-Cas functions from the prokaryotic envelope
Purpose of review: CRISPR-Cas systems are prokaryotic immune systems against invading nucleic acids that adapt as new environmental threats arise. There are emerging examples of CRISPR-Cas functions in bacterial physiology beyond their role in adaptive immunity. This highlights the poorly understood, but potentially common, moonlighting functions of these abundant systems. We propose that these noncanonical CRISPR-Cas activities have evolved to respond to stresses at the cell envelope.
Recent findings: Here, we discuss recent literature describing the impact of the extracellular environment on the regulation of CRISPR-Cas systems, and the influence of CRISPR-Cas activity on bacterial physiology. These described noncanonical CRISPR-Cas functions allow the bacterial cell to respond to the extracellular environment, primarily through changes in envelope physiology.
Summary: This review discusses the expanding noncanonical functions of CRISPR-Cas systems, including their roles in virulence, focusing mainly on their relationship to the cell envelope. We first examine the effects of the extracellular environment on regulation of CRISPR-Cas components, and then discuss the impact of CRISPR-Cas systems on bacterial physiology, concentrating on their roles in influencing interactions with the environment including host organisms
Precautionary labelling of foods for allergen content: are we ready for a global framework?
© 2014 Allen et al.; licensee BioMed Central Ltd.Food allergy appears to be on the rise with the current mainstay of treatment centred on allergen avoidance. Mandatory allergen labelling has improved the safety of food for allergic consumers. However an additional form of voluntary labelling (termed precautionary allergen labelling) has evolved on a wide range of packaged goods, in a bid by manufacturers to minimise risk to customers, and the negative impact on business that might result from exposure to trace amounts of food allergen present during cross-contamination during production. This has resulted in near ubiquitous utilisation of a multitude of different precautionary allergen labels with subsequent confusion amongst many consumers as to their significance. The global nature of food production and manufacturing makes harmonisation of allergen labelling regulations across the world a matter of increasing importance. Addressing inconsistencies across countries with regards to labelling legislation, as well as improvement or even banning of precautionary allergy labelling are both likely to be significant steps forward in improved food safety for allergic families. This article outlines the current status of allergen labelling legislation around the world and reviews the value of current existing precautionary allergen labelling for the allergic consumer. We strongly urge for an international framework to be considered to help roadmap a solution to the weaknesses of the current systems, and discuss the role of legislation in facilitating this
The ROTSE-III Robotic Telescope System
The observation of a prompt optical flash from GRB990123 convincingly
demonstrated the value of autonomous robotic telescope systems. Pursuing a
program of rapid follow-up observations of gamma-ray bursts, the Robotic
Optical Transient Search Experiment (ROTSE) has developed a next-generation
instrument, ROTSE-III, that will continue the search for fast optical
transients. The entire system was designed as an economical robotic facility to
be installed at remote sites throughout the world. There are seven major system
components: optics, optical tube assembly, CCD camera, telescope mount,
enclosure, environmental sensing & protection and data acquisition. Each is
described in turn in the hope that the techniques developed here will be useful
in similar contexts elsewhere.Comment: 19 pages, including 4 figures. To be published in PASP in January,
2003. PASP Number IP02-11
On the full scale and model scale cavitation comparisons of a Deep-V catamaran research vessel
In pushing for greener ships and more sustainable operations, designers and researchers are being challenged to increase vessel performance whilst reducing environmental impact. One topical, and a somewhat challenging aspect of this pursuit, is the reduction in Underwater Radiated Noise (URN). There are several European Collaborative Research Projects currently underway that aim to outline a framework for noise standards, amongst these projects is the Seventh Framework Project (FP7) “Suppression of Underwater Noise Induced by Cavitation” (SONIC) that has been tasked with concentrating on the URN from propeller cavitation; the main contributor to underwater noise generation. As one of the participants of the SONIC project the Newcastle University was involved in the full-scale trials and model-scale propeller testing campaign. The full-scale trial conducted on board Newcastle University’s catamaran research vessel R/V The Princess Royal involved cavitation observations though the dedicated observation windows above each propeller, Propeller Excited Vibration measurements as well as the off-board URN measurements. The model scale tests were made in The Emerson Cavitation Tunnel using a 1:3.5 scale dummy model of the starboard side demi-hull of the vessel. These tests tried to emulate, as best as possible, the full-scale trials in terms of measurement locations and viewing angles
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