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Session B2: VisAdvies Protocol for Testing and Evaluating Pumping Station Pumps on Fish Survivability
Abstract:
In the context of fish welfare, pump manufacturers focus on the development of fish friendly pumps. The assessment of fish survivability in a field situation turns out to be difficult. Lack of migration (eels), presence of fish or insufficient species composition with a narrow range in length class at the moment of the research leads to unreliable conclusions. Therefore a guideline is developed, based on forced exposure of fish, to test and evaluate fish friendly pumps with a standardized method: “VisAdvies protocol for testing and evaluating pumping station pumps on fish survivability”. The protocol serves two purposes. First, the guideline gives direction to the way the test should be performed.
It advises in the fish species the numbers and size classes and the zero-groups (untreated fish) that should be used. It describes how damage and mortality should be categorized in different groups. Part of the test is the assessment of of delayed mortality that may take place a few days after the actual test.
In the second place is the guideline concerned with the evaluation of the results. The final outcome gives the score, based on the survivability rate of all species. A separate test should be carried out for all combinations of pump speed (rpm), discharge (m3/min), and head (m) that are of interest.
The protocol will be illustrated by means of a test in a dry dock in the Netherlands, on a pump of the Bedford company. The pump was especially designed to be fish friendly
Strategische Planungen in naturräumlich definierten Handlungsräumen - Anpassung an den Klimawandel in der Region Starkenburg
Der Beitrag beschreibt die Erarbeitung eines Handlungskonzepts „Anpassung an den
Klimawandel“ im Einzugsgebiet des südhessischen Flusses Gersprenz. Dabei handelt es
sich um einen strategischen Planungsprozess, der im Rahmen des Forschungsprojekts
KLARA-Net gemeinsam mit den regionalen Akteuren durchgefĂĽhrt wird. Die Vorgehensweise
in einem solchen akteursgetragenen Planungsprozess und die einzelnen Bausteine
des Konzepts werden vorgestellt. Ăśberdies werden diese praktischen Erfahrungen
eingebettet in den theoretischen Kontext, wobei insbesondere auf die noch junge Diskussion
zur strategischen Planung bei der Anpassung an den Klimawandel Bezug genommen
wird.This paper describes work to frame an action strategy for “Adaptation to climate
change” for the catchment area of the river Gersprenz in the south of the state of Hesse.
This is an example of a strategic planning process conducted in partnership with regional
actors within the framework of the KLARA-Net research project. The authors
describe the approach adopted in a planning process of this type, which is carried by
the actors involved in it; they then set out the individual component parts of the strategy.
Moreover, practical experience is embedded within the theoretical context; here
reference is made in particular to the discussion – still in its infancy – on strategic
planning in the context of adaptation to climate change
Beurteilung der Gesamtumweltexposition von Silberionen aus Biozid-Produkten
BEURTEILUNG DER GESAMTUMWELTEXPOSITION VON SILBERIONEN AUS BIOZID-PRODUKTEN
Beurteilung der Gesamtumweltexposition von Silberionen aus Biozid-Produkten / Hund-Rinke, Kerstin (Rights reserved) ( -
Imaging the circumstellar envelopes of AGB stars
We report the results of an exploratory program to image the extended
circumstellar envelopes of asymptotic giant branch (AGB) stars in
dust-scattered galactic light. The goal is to characterize the morphology of
the envelopes as a probe of the mass-loss process. The observations consist of
short exposures with the VLT and longer exposures with 1-2m telescopes,
augmented with archival images from the Hubble Space Telescope. We observed 12
AGB stars and detected the circumstellar envelopes in 7. The detected envelopes
have mass loss rates more than about 5 10E-6 solar mass per year, and they can
be seen out to distances of about 1 kpc. The observations provide information
on the mass loss history on time scales up to about 10,000 years. For the five
AGB envelopes in which the circumstellar geometry is well determined by
scattered light observations, all except one (OH348.2-19.7) show deviations
from spherical symmetry. Two (IRC+10216 and IRC+10011) show roughly spherical
envelopes at large radii but asymmetry or bipolarity close to the star; one
(AFGL 2514) shows an extended, elliptical envelope, and one (AFGL 3068) shows a
spiral pattern. The non-spherical structures are all consistent with the
effects of binary interactions. Our observations are in accord with a scenario
in which binary companions play a role in shaping planetary nebulae, and show
that the circumstellar gas is already partly shaped on the AGB, before
evolution to the proto-planetary nebula phase.Comment: Accepted by AA 21 Feb 2006; 18 pages, 14 figs; for high resolution
images, contact mauron at graal.univ-montp2.f
The massive expanding molecular torus in the planetary nebula NGC 6302
We measure the mass and kinematics of the massive molecular torus in the
planetary nebula NGC 6302. The nebula is the proto-typical butterfly nebula.
The origin of the wing-like morphology is disputed: determining the mass-loss
history of the confining torus is an important step in understanding the
formation of this structure. We performed submillimeter observations with JCMT
and the SMA interferometer. The continuum emission as well as the J=2-1 and 3-2
transitions of 12CO and 13CO are analysed at arcsecond resolution. The CO
emission indicates a mass of the torus of ~ 2Msun +/- 1Msun. The 12CO and 13CO
emission matches the dark lane seen in absorption in the Halpha image of the
object. The CO torus is expanding with a velocity of ~ 8 km/s, centred at
Vlsr=-31.5 km/s. The size and expansion velocity of the torus indicates that
the torus was ejected from ~ 7500 yr to 2900 yr ago, with a mass-loss rate of
5x10^{-4}Msun/yr. We also see a ballistic component in the CO images with a
velocity gradient of 140 km/s/pc.
The derived mass-loss history of the torus favours binary interaction as the
cause of the ejection of the torus. We predict the existence of a companion
with an orbital period P < 1 month.Comment: 13 pages, 10 figures, accepted for publication in A&
Ectopic pregnancy: when is expectant management safe?
This study was conducted to evaluate expectant management in asymptomatic patients with an initial serum beta-hCG titer of <2,500 IU/l and to determine the independent ability of initial serum beta-hCG titers and trend of serum beta-hCG to predict successful expectant management. A cohort of patients (N = 418) with suspected ectopic pregnancy (EP) between January 1991 and July 2008 is described. Three groups were defined: group I (n = 182), immediate surgical intervention (<24 h); group IIa (n = 130), unsuccessful expectant management (surgical intervention during follow-up), and group IIb (n = 99), successful expectant management (spontaneous regression of trophoblast). Hospital protocol was not complied in 35 cases (Table 1). Beta-hCG levels >3,000 IU/l occur in our expectant management group; however, none of these cases were successful. Unnecessary surgery was prevented in 14% (n = 7) of asymptomatic patients with initial beta-hCG of >2,000 IU/l. The success rate of expectant management was 49%, without a rise in complication rate or number of acute cases. In conclusion, the initial serum beta-hCG cutoff level of 2,000 IU/l is not a rigid upper limit for accepting expectant management in suspected EP and best practice is case specific. In asymptomatic patients, the serum beta-hCG cutoff level of at least 2,500 IU/l can be used for expectant management. This cutoff could be higher, but interpretation is limited due to censure in follow-up inherent to the predefined clinical protocol. There is no gain in including patients for expectant management with initial serum beta-hCG level >3,000 IU/l
Low-Mass Binary Induced Outflows from Asymptotic Giant Branch Stars
A significant fraction of planetary nebulae (PNe) and proto-planetary nebulae
(PPNe) exhibit aspherical, axisymmetric structures, many of which are highly
collimated. The origin of these structures is not entirely understood, however
recent evidence suggests that many observed PNe harbor binary systems, which
may play a role in their shaping. In an effort to understand how binaries may
produce such asymmetries, we study the effect of low-mass (< 0.3 M_sun)
companions (planets, brown dwarfs and low-mass main sequence stars) embedded
into the envelope of a 3.0 M_sun star during three epochs of its evolution (Red
Giant Branch, Asymptotic Giant Branch (AGB), interpulse AGB). We find that
common envelope evolution can lead to three qualitatively different
consequences: (i) direct ejection of envelope material resulting in a
predominately equatorial outflow, (ii) spin-up of the envelope resulting in the
possibility of powering an explosive dynamo driven jet and (iii) tidal
shredding of the companion into a disc which facilitates a disc driven jet. We
study how these features depend on the secondary's mass and discuss
observational consequences.Comment: 24 pages, 6 figures, submitted to MNRA
Coordinated Analyses of Presolar Grains in the Allan Hills 77307 and Queen Elizabeth Range 99177 Meteorites
We report the identification of presolar silicates (~177 ppm), presolar
oxides (~11 ppm), and one presolar SiO2 grain in the Allan Hills (ALHA) 77307
chondrite. Three grains having Si isotopic compositions similar to SiC X and Z
grains were also identified, though the mineral phases are unconfirmed. Similar
abundances of presolar silicates (~152 ppm) and oxides (~8 ppm) were also
uncovered in the primitive CR chondrite Queen Elizabeth Range (QUE) 99177,
along with 13 presolar SiC grains and one presolar silicon nitride. The O
isotopic compositions of the presolar silicates and oxides indicate that most
of the grains condensed in low-mass red giant and asymptotic giant branch
stars. Interestingly, unlike presolar oxides, few presolar silicate grains have
isotopic compositions pointing to low-metallicity, low-mass stars (Group 3).
The 18O-rich (Group 4) silicates, along with the few Group 3 silicates that
were identified, likely have origins in supernova outflows. This is supported
by their O and Si isotopic compositions. Elemental compositions for 74 presolar
silicate grains were determined by scanning Auger spectroscopy. Most of the
grains have non-stoichiometric elemental compositions inconsistent with
pyroxene or olivine, the phases commonly used to fit astronomical spectra, and
have comparable Mg and Fe contents. Non-equilibrium condensation and/or
secondary alteration could produce the high Fe contents. Transmission electron
microscopic analysis of three silicate grains also reveals non-stoichiometric
compositions, attributable to non-equilibrium or multistep condensation, and
very fine scale elemental heterogeneity, possibly due to subsequent annealing.
The mineralogies of presolar silicates identified in meteorites thus far seem
to differ from those in interplanetary dust particles.Comment: 23 pages, 16 figure
Dietary supplement use among health care professionals enrolled in an online curriculum on herbs and dietary supplements
BACKGROUND: Although many health care professionals (HCPs) in the United States have been educated about and recommend dietary supplements, little is known about their personal use of dietary supplements and factors associated with their use. METHODS: We surveyed HCPs at the point of their enrollment in an on-line course about dietary supplements between September, 2004 and May, 2005. We used multivariable logistic regression to analyze demographic and practice factors associated with use of dietary supplements. RESULTS: Of the 1249 health care professionals surveyed, 81 % reported having used a vitamin, mineral, or other non-herbal dietary supplements in the last week. Use varied by profession with highest rates among nurses (88%), physician assistants or nurse practitioners (84 %) and the lowest rates among pharmacists (66%) and trainees (72%). The most frequently used supplements were multivitamins (60%), calcium (40%), vitamin B (31%), vitamin C (30%), and fish oil (24%). Factors associated with higher supplement use were older age, female, high knowledge of dietary supplements, and discussing dietary supplements with patients. In our adjusted model, nurses were more likely than other professionals to use a multivitamin and students were more likely to use calcium. CONCLUSION: Among HCPs enrolled in an on-line course about dietary supplements, women, older clinicians, those with higher knowledge and those who talk with patients about dietary supplements had higher use of dietary supplements. Additional research is necessary to understand the impact of professionals' personal use of dietary supplements on communication with patients about them
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