5,149 research outputs found
Better by design: Business preferences for environmental regulatory reform
We present the preferences for environmental regulatory reform expressed by 30 UK businesses and industry bodies from 5 sectors. While five strongly preferred voluntary regulation, seven expressed doubts about its effectiveness, and 18 expressed no general preference between instrument types. Voluntary approaches were valued for flexibility and lower burdens, but direct regulation offered stability and a level playing field. Respondents sought regulatory frameworks that: are coherent; balance clarity, prescription and flexibility; are enabled by positive regulatory relationships; administratively efficient; targeted according to risk magnitude and character; evidence-based and that deliver long-term market stability for regulatees. Anticipated differences in performance between types of instrument can be undermined by poor implementation. Results underline the need for policy makers and regulators to tailor an effective mix of instruments for a given sector, and to overcome analytical, institutional and political barriers to greater coherence, to better coordinate existing instruments and tackle new environmental challenges as they emerge
Natural Enemies of Cranberry Fruitworm, \u3ci\u3eAcrobasis Vaccinii\u3c/i\u3e, (Lepidoptera: Pyraudae) in Michigan Highbush Blueberries
A two-year study was conducted in Michigan highbush blueberries to determine the complex of parasitoids attacking cranberry fruitworm, Acrobasis vaccinii. Eight parasitoid species and one fungal pathogen were collected. Parasitism of collected hosts ranged from 6.6% to 28.1%. The more common larval parasitoid encountered was Campoletis patsuiketorum (Hymenoptera: Ichneumonidae). The more common parasitoid recovered from fruitworm hibernacula was Villa lateralis (Diptera: Bombyliidae). This study documented six unreported natural enemies of cranberry fruitworm, including C. patsuiketorum; V. lateralis; Diadegma compressum (Hymenoptera: Ichneumonidae); Compsilura concinnata (Diptera: Tachinidae); Memorilla pyste (Diptera: Tachinidae); an undescribed Microtypus species (Hymenoptera: Braconidae); and a fungal pathogen, Paecilomyces near farinosus. This is the first known host association for the undescribed Microtypus species, and increases the known parasitoid complex of cranberry fruitworm to 17 species
Aging and aerobic fitness affect the contribution of noradrenergic sympathetic nerves to the rapid cutaneous vasodilator response to local heating
Sedentary aging results in a diminished rapid cutaneous vasodilator response to local heating. We investigated whether this diminished response was due to altered contributions of noradrenergic sympathetic nerves; assessing 1) the age-related decline and, 2) the effect of aerobic fitness. We measured skin blood flow (SkBF)(laser-Doppler flowmetry) in young (24±1 yr) and older (64±1 yr) endurance-trained and sedentary men (n=7 per group) at baseline and during 35 min of local skin heating to 42 °C at three forearm sites: 1) untreated; 2) bretylium tosylate (BT), preventing neurotransmitter release from noradrenergic sympathetic nerves; and 3) yohimbine and propranolol (YP), antagonising α- and β-adrenergic receptors. SkBF was converted to cutaneous vascular conductance (CVC) (SkBF/mean arterial pressure) and normalized to maximal CVC (%CVCmax) achieved by skin heating to 44 °C. Pharmacological agents were administered using microdialysis. In the young trained, the rapid vasodilator response was reduced at the BT and YP sites (P0.05) but treatment with BT did (P>0.05). Neither BT nor YP treatments affected the rapid vasodilator response in the older sedentary group (P>0.05). These data suggest that the age-related reduction in the rapid vasodilator response is due to an impairment of sympathetic-dependent mechanisms, which can be partly attenuated with habitual aerobic exercise. Rapid vasodilation involves noradrenergic neurotransmitters in young trained men, and non-adrenergic sympathetic cotransmitters (e.g.,
neuropeptide Y) in young sedentary and older trained men, possibly as a compensatory mechanism. Finally, in older sedentary men, the rapid vasodilation appears not to involve the sympathetic system
A lower limit on the dark particle mass from dSphs
We use dwarf spheroidal galaxies as a tool to attempt to put precise lower
limits on the mass of the dark matter particle, assuming it is a sterile
neutrino. We begin by making cored dark halo fits to the line of sight velocity
dispersions as a function of projected radius (taken from Walker et al. 2007)
for six of the Milky Way's dwarf spheroidal galaxies. We test Osipkov-Merritt
velocity anisotropy profiles, but find that no benefit is gained over constant
velocity anisotropy. In contrast to previous attempts, we do not assume any
relation between the stellar velocity dispersions and the dark matter ones, but
instead we solve directly for the sterile neutrino velocity dispersion at all
radii by using the equation of state for a partially degenerate neutrino gas
(which ensures hydrostatic equilibrium of the sterile neutrino halo). This
yields a 1:1 relation between the sterile neutrino density and velocity
dispersion, and therefore gives us an accurate estimate of the Tremaine-Gunn
limit at all radii. By varying the sterile neutrino particle mass, we locate
the minimum mass for all six dwarf spheroidals such that the Tremaine-Gunn
limit is not exceeded at any radius (in particular at the centre). We find
sizeable differences between the ranges of feasible sterile neutrino particle
mass for each dwarf, but interestingly there exists a small range 270-280eV
which is consistent with all dSphs at the 1- level.Comment: 13 pages, 2 figures, 1 tabl
Simulation of Pasture Phase Options for Mixed Livestock and Cropping Enterprises
In southern Australia, 50% of grain-producing farms also run beef and/or sheep enterprises. Legume pasture leys are used to replace soil nitrogen and manage crop disease risks. Deep-rooted perennials, predominantly lucerne (Medicago sativa), are replacing annual Trifolium subterraneum-based leys to increase pasture production. They also have the environmental benefits of limiting soil acidity, rising water tables and dryland salinity. After recent droughts depletion of soil water by lucerne has penalised wheat yields. Decision support tools can help farmers evaluate the long-term effects of grazed annual and perennial leys on animal and crop production at the whole farm level
Assessment of the limitations on the seismic detectability of injected CO2 within a deep geological reservoir
Aquistore is a deep saline CO2 storage research and demonstration project located near Estevan, Saskatchewan where CO2 is transported via pipeline and injected into a sandstone reservoir ∼3200 m below the surface. A pre-injection time-lapse analysis performed on two sparse 3D seismic datasets was used to characterise the background time-lapse signal-to-noise level at the storage site. The time-lapse analysis revealed that the lowest global nRMS was 0.07 which was taken to represent the level above which CO2 would be detectable in the reservoir. We investigate the conditions under which the injected CO2 can be detected above the defined minimum noise level through Gassmann fluid substitution and 3D seismic forward modelling. Additionally, Wave Unix was used to simulate the seismic response of the reservoir due to the injected CO2 by generating the synthetic surface reflection seismic data from an explosive surface P-wave source. We generated noise-free synthetic seismograms for the baseline model as well as for the 2-phase fluid replacement of brine with CO2 for CO2 concentrations up to 100% within the target zone – the monitors. The baseline and monitor traces from the 3D seismic survey at Aquistore are used as the noise traces in this study, and were added to their respective baseline and monitor synthetic traces. The nRMS within the reservoir was then computed for the noisy baseline and various noisy monitor surveys and was used in the assessment of the limitation to the detection of the injected CO2 in the reservoir under the background noise level at the site. We are able to conclude that the time-lapse repeatability will not limit the ability to monitor the CO2 induced changes in the reservoir at the Aquistore storage site
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