7,252 research outputs found
Recommended from our members
Geographic variation and evolutionary history of Dipodomys nitratoides (Rodentia: Heteromyidae), a species in severe decline
We examined geographic patterns of diversification in the highly impacted San Joaquin kangaroo rat, Dipodomys nitratoides, throughout its range in the San Joaquin Valley and adjacent basins in central California. The currently recognized subspecies were distinct by the original set of mensural and color variables used in their formal diagnoses, although the Fresno kangaroo rat (D. n. exilis) is the most strongly differentiated with sharp steps in character clines relative to the adjacent Tipton (D. n. nitratoides) and short-nosed (D. n. brevinasus) races. The latter two grade more smoothly into one another but still exhibit independent, and different, character clines within themselves. At the molecular level, as delineated by mtDNA cytochrome b sequences, most population samples retain high levels of diversity despite significant retraction in the species range and severe fragmentation of local populations in recent decades due primarily to landscape conversion for agriculture and secondarily to increased urbanization. Haplotype apportionment bears no relationship to morphologically defined subspecies boundaries. Rather, a haplotype network is shallow, most haplotypes are single-step variants, and the time to coalescence is substantially more recent than the time of species split between D. nitratoides and its sister taxon, D. merriami. The biogeographic history of the species within the San Joaquin Valley appears tied to mid-late Pleistocene expansion following significant drying of the valley resulting from the rain shadow produced by uplift of the Central Coastal Ranges
Making and doing: critical and cross-disciplinary engagement within interdisciplinary iSchools
Introduction:
Like many iSchools, the Faculty of Information at the University of Toronto integrates a variety of
disciplinary fields (LIS, Records Management, Information Systems and Design, Critical and Cultural
theory, Policy, Technology Studies, etc.) and a diversity of institutional foci (libraries, archives, museums,
universities, government, corporate contexts, etc.) Such diversity is both an asset and a challenge for the
Faculty as we seek to provide professional and academic training for our masters and PhD students and
look to engage in collaborative work among faculty members. Importantly, the types of skills and
experiences that we collectively bring to bear and the kinds of issues and questions addressed by faculty
and graduate students transgress more than just standard disciplinary barriers. In order to address the
important social, cultural, and political questions posed by the continuing transformation of information
practices, the boundary between material and technical work and reflexive, critical, social scholarship must
be bridged. This is a crucial challenge for iSchools ??? how do we bring various perspectives, interests, and
backgrounds to bear while staying connected through an emphasis on common theoretical concerns
Trustworthy repositories: Audit and certification (TRAC) Cline Library internal audit, spring 2014
Audit and Certification of Trustworthy Digital Repositories (TRAC) is a recommended practice developed by the Consultative Committee for Space Data Systems. The TRAC international standard (ISO 16363:2012) provides institutions with guidelines for performing internal audits to evaluate the trustworthiness of digital repositories, and creates a structure to support external certification of repositories. TRAC establishes criteria, evidence, best practices and controls that digital repositories can use to assess their activities in the areas of organizational infrastructure, digital object management, and technical infrastructure and risk management. The Cline Library at Northern Arizona University has undertaken an internal audit based on TRAC in order to evaluate the policies, procedures and workflows of the existing digital archives and to prepare for the development and implementation of the proposed institutional repository. The following document provides an overview of the results and recommendations produced by this internal audit
Highly Ionized Potassium Lines in Solar X-ray Spectra and the Abundance of Potassium
The abundance of potassium is derived from X-ray lines observed during flares
by the RESIK instrument on the solar mission CORONAS-F between 3.53 A and 3.57
A. The lines include those emitted by He-like K and Li-like K dielectronic
satellites, which have been synthesized using the CHIANTI atomic code and newly
calculated atomic data. There is good agreement of observed and synthesized
spectra, and the theoretical behavior of the spectra with varying temperature
estimated from the ratio of the two GOES channels is correctly predicted. The
observed fluxes of the He-like K resonance line per unit emission measure gives
log A(K) = 5.86 (on a scale log A(H) = 12), with a total range of a factor 2.9.
This is higher than photospheric abundance estimates by a factor 5.5, a
slightly greater enhancement than for other elements with first ionization
potential (FIP) less than about 10 eV. There is, then, the possibility that
enrichment of low-FIP elements in coronal plasmas depends weakly on the value
of the FIP which for K is extremely low (4.34 eV). Our work also suggests that
fractionation of elements to form the FIP effect occurs in the low chromosphere
rather than higher up, as in some models.Comment: 14 pages, 3 figure
Comparison of CRNAs with and without Supervision on Cost and Safety of Anesthesia
There has been controversy in the field of anesthesia regarding whether certified registered nurse anesthetists (CRNAs) or anesthesiologists provide safer and more cost-effective care. This study was done to compare CRNAs with and without supervision of an anesthesiologist and how it affects the cost and safety of anesthesia delivery. The results of this systematic review could provide information to affect policies regarding who is responsible for providing anesthesia, with safety and cost as the necessary variables. Twenty articles, published between the years 1999 and 2017, retrieved from the databases PubMed and Cinahl were analyzed and synthesized as part of this review. Studies that examined safety and cost effectiveness among CRNAs and anesthesiologists were included in this review. All but one article was from the US. Sample sizes in the studies ranged from 27 to over 1,000,000 participants ranging from patient chart reviews to surveys. Findings of this review showed that there was not enough evidence to conclude if CRNAs are more cost effective or provide better quality care alone or supervised
Letter from the Waikato
Because 2016 is the 20th anniversary of Te WhÄriki and 12 years since the publication of the first 10 books of Kei Tua o te Pae (Ministry of Education, 1996; 2004), we have been reflecting on developments in teaching, particularly in assessment practices in early childhood services
New Oral Anticoagulants in the Treatment of Pulmonary Embolism: Efficacy, Bleeding Risk, and Monitoring
Anticoagulation therapy is mandatory in patients with pulmonary embolism to prevent significant morbidity and mortality. The mainstay of therapy has been vitamin-K antagonist therapy bridged with parenteral anticoagulants. The recent approval of new oral anticoagulants (NOACs: apixaban, dabigatran, and rivaroxaban) has generated significant interest in their role in managing venous thromboembolism, especially pulmonary embolism due to their improved pharmacokinetic and pharmacodynamic profiles, predictable anticoagulant response, and lack of required efficacy monitoring. This paper addresses the available literature, on-going clinical trials, highlights critical points, and discusses potential advantages and disadvantages of the new oral anticoagulants in patients with pulmonary embolism
Applying rotorcraft modelling technology to renewable energy research
The perceived need to reduce mankind's impact on the global climate motivates towards a future society in which a significant proportion of its energy needs will be extracted from the winds and the tides of the planet. This paper shows several examples of the application of Brown's Vorticity Transport Model, originally developed to perform simulations of helicopter aeromechanics and wake dynamics, to the analysis of the performance of renewable energy devices and their possible impact on the environment. Prediction of the loading on wind turbines introduces significant additional challenges to such a model, including the need to account fully for the effects of radial flow on blade stall. The wake-mediated aerodynamic interactions that occur within a wind farm can reduce its power output significantly, but this problem is very similar to that where the aerodynamic unsteadiness of the coupled wake of the main and tail rotors of a helicopter can result in significantly increased pilot workload. The helicopter-related problem of brownout, encountered during operations in desert conditions, has its analogue in the entrainment of sediment into the wakes of tidal turbines. In both cases it may be possible to ameliorate the influence of the rotor on its environment by careful and well-informed design. Finally, calculations of the distortion and dispersal of the exhaust plumes of a helicopter by the wake of its rotor allow insight into how wind turbines might interfere with the dispersal of pollutants from nearby industrial sites. These examples show how cross-disciplinary information transfer between the rotorcraft field and the renewable energy community is helping to develop the technologies that will be required by our future society, as well as helping to understand the environmental issues that might need to be faced as these technologies become more prevalent
Domestic violence perpetrator programmes : an historical overview. Briefing note 2
Since the 1970s, the feminist movement has campaigned to bring the issue of domestic violence to the social agenda. Yet, all too often, the men who perpetrate violence and abuse against their partners have remained absent, and left to continue their abusive regime. The need to address this absence was the basis upon which domestic violence perpetrator programmes (DVPPs) emerged
- ā¦