1,066 research outputs found
Incorporating sustainable forestry into standards for professional forestry education
In 1991, the National Association of Professional Forestry Schools and Colleges (NAPFSC) and the Society of American Foresters (SAF) co-hosted a three-day Forest Resources Education Symposium, entitled Forest Resources Management in the 21st Century: Will Forestry Education Meet the Challenge? The objectives of the national symposium were to present major forces shaping the country\u27s management of forest resources, and then to discuss the adequacy of educational criteria in preparing tomorrow\u27s resource managers to excel under an expanding array of consumer and employer demands. As an outcome, the discussants developed a summary of specific challenges and solutions within five issue areas: The Future of Forestry, Future Educational Needs, Defining Appropriate Curricula, Student Characteristics, and Faculty Characteristics. Many existing problems were identified as a result of that process, as well as potentially useful strategies for corrective action
Cooperative action in eukaryotic gene regulation: physical properties of a viral example
The Epstein-Barr virus (EBV) infects more than 90% of the human population,
and is the cause of several both serious and mild diseases. It is a
tumorivirus, and has been widely studied as a model system for gene
(de)regulation in human. A central feature of the EBV life cycle is its ability
to persist in human B cells in states denoted latency I, II and III. In latency
III the host cell is driven to cell proliferation and hence expansion of the
viral population, but does not enter the lytic pathway, and no new virions are
produced, while the latency I state is almost completely dormant. In this paper
we study a physico-chemical model of the switch between latency I and latency
III in EBV. We show that the unusually large number of binding sites of two
competing transcription factors, one viral and one from the host, serves to
make the switch sharper (higher Hill coefficient), either by cooperative
binding between molecules of the same species when they bind, or by competition
between the two species if there is sufficient steric hindrance.Comment: 7 pages, 6 figures, 1 tabl
Epstein-Barr virus IL-10 gene expression by a recombinant murine gammaherpesvirus in vivo enhances acute pathogenicity but does not affect latency or reactivation.
BackgroundMany viral genes affect cytokine function within infected hosts, with interleukin 10 (IL-10) as a commonly targeted mediator. Epstein-Barr virus (EBV) encodes an IL-10 homologue (vIL-10) expressed during productive (lytic) infection and induces expression of cellular IL-10 (cIL-10) during latency. This study explored the role of vIL-10 in a murine gammaherpesvirus (MHV) model of viral infection.MethodsThe EBV vIL-10 gene was inserted into MHV-76, a strain which lacks the ability to induce cIL-10, by recombination in transfected mouse cells. Mice were infected intranasally with the recombinant, vIL-10-containing MHV-76 or control virus strains and assayed at various days post infection for lung virus titer, spleen cell number, percentage of latently infected spleen cells and ability to reactivate virus from spleen cells.ResultsRecombinant murine gammaherpesvirus expressing EBV vIL-10 rose to significantly higher titers in lungs and promoted an increase in spleen cell number in infected mice in comparison to MHV strains lacking the vIL-10 gene. However, vIL-10 expression did not alter the quantity of latent virus in the spleen or its ability to reactivate.ConclusionsIn this mouse model of gammaherpesvirus infection, EBV vIL-10 appears to influence acute-phase pathogenicity. Given that EBV and MHV wild-type strains contain other genes that induce cIL-10 expression in latency (e.g. LMP-1 and M2, respectively), vIL-10 may have evolved to serve the specific role in acute infection of enlarging the permissive host cell population, perhaps to facilitate initial survival and dissemination of viral-infected cells
Integrated water resources management in North Georgia implications of wastewater management policy
Water management in the southeast, and
particularly in Georgia, has become increasingly more
complex due to rapid population growth, dwindling water
supplies, water quality and instream flow concerns, and
allocation disputes with neighboring states. The Georgia
state legislature responded with two key initiatives: SB
130, passed in 2001, which formed the Metropolitan North
Georgia Water Planning District (MNGWPD), and HB
237, passed in 2004, which requires the development of a
Comprehensive Statewide Water Plan (CSWP). In 2003,
the MNGWPD adopted wastewater management,
watershed protection, and water supply and conservation
plans that will guide water resources in metropolitan
Atlanta for the next 30 years.
Implementation costs of the MNGWPD water and
wastewater plans through 2030 has been estimated to total
$60B. To conserve financial resources and encourage a
sustainable development pattern, it is necessary to
prioritize these investments, i.e., focus investments upon
areas have the ability to increase population density due to
the proximity of existing services. Currently, growth
management policies in some jurisdictions encourage
septic system development, increasing overall wastewater
treatment costs and interfering with water management
goals.Sponsored by:
Georgia Environmental Protection Division
U.S. Geological Survey, Georgia Water Science Center
U.S. Department of Agriculture, Natural Resources Conservation Service
Georgia Institute of Technology, Georgia Water Resources Institute
The University of Georgia, Water Resources Facult
VerdictDB: Universalizing Approximate Query Processing
Despite 25 years of research in academia, approximate query processing (AQP)
has had little industrial adoption. One of the major causes of this slow
adoption is the reluctance of traditional vendors to make radical changes to
their legacy codebases, and the preoccupation of newer vendors (e.g.,
SQL-on-Hadoop products) with implementing standard features. Additionally, the
few AQP engines that are available are each tied to a specific platform and
require users to completely abandon their existing databases---an unrealistic
expectation given the infancy of the AQP technology. Therefore, we argue that a
universal solution is needed: a database-agnostic approximation engine that
will widen the reach of this emerging technology across various platforms.
Our proposal, called VerdictDB, uses a middleware architecture that requires
no changes to the backend database, and thus, can work with all off-the-shelf
engines. Operating at the driver-level, VerdictDB intercepts analytical queries
issued to the database and rewrites them into another query that, if executed
by any standard relational engine, will yield sufficient information for
computing an approximate answer. VerdictDB uses the returned result set to
compute an approximate answer and error estimates, which are then passed on to
the user or application. However, lack of access to the query execution layer
introduces significant challenges in terms of generality, correctness, and
efficiency. This paper shows how VerdictDB overcomes these challenges and
delivers up to 171 speedup (18.45 on average) for a variety of
existing engines, such as Impala, Spark SQL, and Amazon Redshift, while
incurring less than 2.6% relative error. VerdictDB is open-sourced under Apache
License.Comment: Extended technical report of the paper that appeared in Proceedings
of the 2018 International Conference on Management of Data, pp. 1461-1476.
ACM, 201
Neurofilament light plasma concentration positively associates with age and negatively associates with weight and height in the dog
Plasma neurofilament light chain (pNfL) concentration is a biomarker for neuroaxonal injury and degeneration and can be used to monitor response to treatment. Spontaneous canine neurodegenerative diseases are a valuable comparative resource for understanding similar human conditions and as large animal treatment models. The features of pNfL concentration in healthy dogs is not well established. We present data reporting basic pNfL concentration trends in the Labrador Retriever breed. Fifty-five Labrador Retrievers were enrolled. pNfL concentration was measured and correlated to age, sex, neuter status, height, weight, body mass index, and coat color. We found increased pNfL with age (P < 0.0001), shorter stature (P = 0.009) and decreased body weight (P < 0.001). These are similar to findings reported in humans. pNfL concentration did not correlate with sex, BMI or coat color. This data further supports findings that pNfL increase with age in a canine population but highlights a need to consider weight and height when determining normal pNfL concentration in canine populations
In Defense of the Epistemic Imperative
Sample (2015) argues that scientists ought not to believe that their theories are true because they cannot fulfill the epistemic obligation to take the diachronic perspective on their theories. I reply that Sample’s argument imposes an inordinately heavy epistemic obligation on scientists, and that it spells doom not only for scientific theories but also for observational beliefs and philosophical ideas that Samples endorses. I also delineate what I take to be a reasonable epistemic obligation for scientists. In sum, philosophers ought to impose on scientists only an epistemic standard that they are willing to impose on themselves
A mathematical description of nerve fiber bundle trajectories and their variability in the human retina
AbstractWe developed a mathematical model wherein retinal nerve fiber trajectories can be described and the corresponding inter-subject variability analyzed. The model was based on traced nerve fiber bundle trajectories extracted from 55 fundus photographs of 55 human subjects. The model resembled the typical retinal nerve fiber layer course within 20° eccentricity. Depending on the location of the visual field test point, the standard deviation of the calculated corresponding angular location at the optic nerve head circumference ranged from less than 1° to 18°, with an average of 8.8°
Jamming and Fluctuations in Granular Drag
We investigate the dynamic evolution of jamming in granular media through
fluctuations in the granular drag force. The successive collapse and formation
of jammed states give a stick-slip nature to the fluctuations which is
independent of the contact surface between the grains and the dragged object --
thus implying that the stress-induced collapse is nucleated in the bulk of the
granular sample. We also find that while the fluctuations are periodic at small
depths, they become "stepped" at large depths, a transition which we interpret
as a consequence of the long-range nature of the force chains.Comment: 7 pages, 4 figures, RevTe
Effect of analgesic therapy on clinical outcome measures in a randomized controlled trial using client-owned dogs with hip osteoarthritis
BACKGROUND: Pain and impaired mobility because of osteoarthritis (OA) is common in dogs and humans. Efficacy studies of analgesic drug treatment of dogs with naturally occurring OA may be challenging, as a caregiver placebo effect is typically evident. However, little is known about effect sizes of common outcome-measures in canine clinical trials evaluating treatment of OA pain. Forty-nine client-owned dogs with hip OA were enrolled in a randomized, double-blinded placebo-controlled prospective trial. After a 1 week baseline period, dogs were randomly assigned to a treatment (ABT-116 – transient receptor potential vanilloid 1 (TRPV1) antagonist, Carprofen – non-steroidal anti-inflammatory drug (NSAID), Tramadol - synthetic opiate, or Placebo) for 2 weeks. Outcome-measures included physical examination parameters, owner questionnaire, activity monitoring, gait analysis, and use of rescue medication. RESULTS: Acute hyperthermia developed after ABT-116 treatment (P < 0.001). Treatment with carprofen (P ≤ 0.01) and tramadol (P ≤ 0.001) led to improved mobility assessed by owner questionnaire. Nighttime activity was increased after ABT-116 treatment (P = 0.01). Kinetic gait analysis did not reveal significant treatment effects. Use of rescue treatment decreased with treatment in the ABT-116 and Carprofen groups (P < 0.001). Questionnaire score and activity count at the end of treatment were correlated with age, clinical severity at trial entry, and outcome measure baseline status (S(R) ≥ ±0.40, P ≤ 0.005). Placebo treatment effects were evident with all variables studied. CONCLUSION: Treatment of hip OA in client-owned dogs is associated with a placebo effect for all variables that are commonly used for efficacy studies of analgesic drugs. This likely reflects caregiver bias or the phenomenon of regression to the mean. In the present study, outcome measures with significant effects also varied between groups, highlighting the value of using multiple outcome measures, as well as an a priori analysis of effect size associated with each measure. Effect size data from the present study could be used to inform design of future trials studying analgesic treatment of canine OA. Our results suggest that analgesic treatment with ABT-116 is not as effective as carprofen or tramadol for treatment of hip arthritis pain in client-owned dogs
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