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Session D3: Net Ecosystem Services Analysis as a Floodplain Restoration and Management Tool
Abstract:
Established ecological fundamentals typically determine design, success and efficiency of restoration and management of floodplain and aquatic resources. Some of the more common criticisms center around the facts that commonly used methods: 1) do not have a quantitative basis for the estimates, 2) are not transparent to allow thorough review and stakeholder input, and 3) do not demonstrate direct and indirect benefits to the affected public. Integrating ecosystem services concepts and approaches and their evaluation for planning and performing ecological restoration is a practical alternative to the traditional restoration approach and can improve the restoration product, provide stakeholder support and ultimate value to the local public.
Increased human influence and potential global influences (e.g. climate change) will directly affect floodplains and aquatic resources in the future with potential for substantial changes in physical effects (e.g. flooding and storm events), chemical changes (water quality), biological (changes in habitat and species distribution), and ultimately how humans use the services provided by these ecosystems. This will have substantial financial and human use implications in floodplain areas and general ecosystem health that provide these services to humans. Recent scientific thinking is increasingly focused on an ecosystems services approach. The concept, advanced by the United Nation’ Millennium Ecosystem Assessment (2005), brings a fresh approach to identifying and managing environmental risks within the limited financial and infrastructural resources available to most entities. This presentation will focus on the use of Net Ecosystem Services Analysis (NESA) for maximizing benefit and prioritizing future expenditures. The key to this is the quantification and rigorous analysis of the services provided by ecosystems that are important to people. NESA case studies will be used to demonstrate quantification tools and approaches used in similar assessments to manage floodplain ecosystem services
CD4 Cell Count Threshold for Cryptococcal Antigen Screening of HIV-Infected Individuals: A Systematic Review and Meta-analysis.
Background: Current guidelines recommend screening all people living with human immunodeficiency virus (PLHIV) who have a CD4 count ≤100 cells/µL for cryptococcal antigen (CrAg) to identify those patients who could benefit from preemptive fluconazole treatment prior to the onset of meningitis. We conducted a systematic review to assess the prevalence of CrAg positivity at different CD4 cell counts. Methods: We searched 4 databases and abstracts from 3 conferences up to 1 September 2017 for studies reporting prevalence of CrAg positivity according to CD4 cell count strata. Prevalence estimates were pooled using random effects models. Results: Sixty studies met our inclusion criteria. The pooled prevalence of cryptococcal antigenemia was 6.5% (95% confidence interval [CI], 5.7%-7.3%; 54 studies) among patients with CD4 count ≤100 cells/µL and 2.0% (95% CI, 1.2%-2.7%; 21 studies) among patients with CD4 count 101-200 cells/µL. Twenty-one studies provided sufficient information to compare CrAg prevalence per strata; overall, 18.6% (95% CI, 15.4%-22.2%) of the CrAg-positive cases identified at ≤200 cells/µL (n = 11823) were identified among individuals with a CD4 count 101-200 cells/µL. CrAg prevalence was higher among inpatients (9.8% [95% CI, 4.0%-15.5%]) compared with outpatients (6.3% [95% CI, 5.3%-7.4%]). Conclusions: The findings of this review support current recommendations to screen all PLHIV who have a CD4 count ≤100 cells/µL for CrAg and suggest that screening may be considered at CD4 cell count ≤200 cells/µL
The Radial Velocity Distribution of Class I and Flat-Spectrum Protostars
We analyze radial velocities for a sample of 31 Class I and flat spectrum
protostars in Taurus-Auriga, rho Ophiuchi and Serpens for evidence of the
global dynamical state of extremely young stellar populations buried within
parental molecular clouds. Comparing the radial velocity of each protostar to
that of the local CO gas, we are able to constrain the one dimensional radial
velocity dispersion of Class I and flat spectrum objects to ~ 2.5 km/sec or
below. This upper limit to the protostellar velocity dispersion is consistent
with the velocity dispersions of surrounding CO gas which we measure to be ~
1.4 km/sec, suggesting that the motions of protostars and local CO gas are
dynamically linked and dominated by the gravitational potential of the
molecular cloud. However, the upper limit on the protostellar velocity
dispersion could still allow for slightly inflated motions of protostars
relative to the local molecular gas. Four of the protostars analyzed appear to
have velocities more than 3 sigma (7.5 km/sec) away from the central local CO
gas velocity while showing spectroscopic indicators of youth and accretion such
as H_2 emission, HI Br Gamma emission, or K band continuum veiling. These
radial velocity outliers may represent protostellar spectroscopic binaries or
ejected cluster members.Comment: 9 pages in emulate ApJ format, accepted for publication in A
Intermediate-mass black holes and the fundamental plane of black hole accretion
We present new 5 GHz VLA observations of a sample of 8 active
intermediate-mass black holes with masses
found in galaxies with stellar masses . We
detected 5 of the 8 sources at high significance. Of the detections, 4 were
consistent with a point source, and one (SDSS J095418.15+471725.1, with black
hole mass ) clearly shows extended emission that has a
jet morphology. Combining our new radio data with the black hole masses and
literature X-ray measurements, we put the sources on the fundamental plane of
black hole accretion. We find that the extent to which the sources agree with
the fundamental plane depends on their star-forming/composite/AGN
classification based on optical narrow emission line ratios. he single
star-forming source is inconsistent with the fundamental plane. The three
composite sources are consistent, and three of the four AGN sources are
inconsistent with the fundamental plane. We argue that this inconsistency is
genuine and not a result of misattributing star-formation to black hole
activity. Instead, we identify the sources in our sample that have AGN-like
optical emission line ratios as not following the fundamental plane and thus
caution the use of the fundamental plane to estimate masses without additional
constraints, such as radio spectral index, radiative efficiency, or the
Eddington fraction.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical
Society. 9 pages, 2 figures. Images can be accessed in fits format from
https://doi.org/10.7302/3100-6e6
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