Dealing with construction and demolition waste abroad: lessons for Hong Kong [Part II]

In the second instalment of a two-part article Dr Arthur McInnis and David Hall-Jones of Denton Wilde Sapte finish their look at how construction and demolition (C&D) waste is dealt with in other leading jurisdictions and set out their conclusions for how Hong Kong might address the issue.published_or_final_versio

Dealing with construction and demolition waste abroad: lessons for Hong Kong [Part I]

Few issues in construction give rise to more controversy than dealing with construction and demolition (C&D) waste. The problem is the same the world over. In Hong Kong it has been exacerbated by conflicting definitions in governing primary and secondary legislation as to what qualifies as waste, which affects how it should be dealt with - whether recycled or filled. In the first instalment of a two-part article Dr Arthur McInnis and David Hall-Jones of Denton Wilde Sapte look at how C&D waste is dealt with in other leading jurisdictions and then draw some conclusions for how Hong Kong might address the issue.published_or_final_versio

XCEED™ canola, introduction of the first herbicide tolerant Brassica juncea canola for western Canada

Non-Peer ReviewedCanola-quality Brassica juncea has been developed to provide a reliable method of producing canola in areas prone to heat and drought and where straight-cut combing is desirable. Conventional varieties have been available since 2002 and have been grown on a limited acreage. CLEARFIELD varieties have been developed and will provide improved weed control options for the crop and thereby increase the cultivated acreage. These varieties will be marketed as XCEED canola by Viterra

Edited NSSL meso-scale upper air network data in southwestern Oklahoma, 1966 and 1967

Cover title."Atmospheric General Circulation Technical Document No. 1.

Aqueous route for the synthesis of platinum, ruthenium and ceria nanoparticles on multi-walled carbon nanotubes for the electrooxidation of methanol and ethanol

The electrochemical oxidation of methanol and ethanol in acidic media was studied using electrodes composed of multi-walled carbon nanotubes (MWCNTs) decorated with Pt, Ru and ceria nanoparticles. Polystyrene sulfonate (PSS) was used to disperse the MWCNTs in water and provide nucleation sites for the growth of catalyst nanoparticles. Composite electrodes were characterized for structural and electrochemical properties and all electrodes modified with Ru displayed greater catalytic ability for alcohol oxidation than those without Ru. In addition, the inclusion of ceria seemed to increase the catalytic ability in every sample suggesting a synergistic effect between Pt, Ru and ceria for the oxidation of methanol and ethanol. The catalytic effect of Pt and Ru concentration was studied by holding Ru concentrations constant and increasing the concentration of Pt. The same concentration of ceria was used for all modified electrodes. The results of this study show that the electrode prepared from 3:1 Pt:Ru solutions with ceria showed the highest peak current density for methanol oxidation (at 0.6 V vs. Ag/AgCl/Cl-) which was nearly 20 times greater than that for an unmodified Pt electrode. Similar results were seen for ethanol oxidation on the same electrode which resulted in peak current densities greater than 20 times those for the unmodified Pt electrode at 0.8 V versus Ag/AgCl/Cl-

Imaging of Laser-Plasma X-ray Emission with Charge-Injection Devices

This work details the method of obtaining time-integrated images of laser–plasma x-ray emission using charge-injection devices (CIDs), as has been demonstrated on the University of Rochester’s 60-beam UV OMEGA laser facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. The CID has an architecture similar to a charge-coupled device. The differences make them more resistant to radiation damage and, therefore, more appropriate for some application in laser–plasma x-ray imaging. CID-recorded images have been obtained with x-ray pinhole cameras, x-ray microscopes, x-ray spectrometers, and monochromatic x-ray imaging systems. Simultaneous images obtained on these systems with calibrated x-ray film have enabled determination of the absolute detection efficiency of the CIDs in the energy range from 2 to 8 keV

Riodinid butterfly fauna (Lepidoptera) of the Cosñipata Region, Peru: Annotated checklist, community structure, and contrast with Lycaenidae

A team of experienced lepidopterists sampled the butterfly fauna of Peru’s Cosñipata Region from 400 to 4,000 m elevation for more than a decade (7,440 field person-hours) and supplemented this sam­ple with data from museum specimens and the scientific literature. An annotated checklist of Cosñipata Riodinidae (Lepidoptera: Papilionoidea) documents 398 species, which represents 29% of the world Rio­dinidae fauna. For each, it lists sample abundance, adult behavior, elevation, and temporal distribution. In the fieldwork sample, 75 species (20.9%) were sampled once and 39 (9.8%) were not encountered (collected or imaged by others). A riodinid species of median abundance was sampled an average of once every 826 field person-hours. Sampled sex ratios were 81.2% male, but were not statistically higher in species in which male perching behavior was observed. We document examples of conspicuous geographic variation in the time of male perching behavior. Species richness is greatest at low elevation and at the transition between the dry and wet seasons. There is little evidence that the community is composed of species restricted to narrow elevational bands or restricted in the adult stage to a single season. Compared with Lycaenidae, Riodinidae are significantly more restricted to lowland habitats and were sampled 2.5 times as frequently with a mean number of individuals per species more than twice as great as that of Lycaenidae

Gause's exclusion principle revisited: artificial modified species and competition

Gause's principle of competition between two species is studied when one of them is sterile. We study the condition for total extinction in the niche, namely, when the sterile population exterminates the native one by an optimal use of resources. A mathematical Lotka-Volterra non linear model of interaction between a native and sterile species is proposed. The condition for total extinction is related to the initial number $M_{o}$ of sterile individuals released in the niche. In fact, the existence of a critical sterile-population value $M_{c}$ is conjectured from numerical analysis and an analytical estimation is found. When spatial diffusion (migration) is considered a critical size territory is found and, for small territory, total extinction exist in any case. This work is motived by the extermination agriculture problem of fruit flies in our region.Comment: 11 pages. Published in Jour.Phys.A Math.Gen. 33, 4877 (2000

Suicide prevention and mood disorders: Self-exclusion agreements for firearms as a suicide prevention strategy

Suicide involves a complex set of behaviors and emotions that lead up to actions that may be based on planning and forethought or the result of impulse. While there are a host of antecedent circumstances the presence of a mood disorder, primarily depression, is the most common factor in suicide. While management of depression is recognized as important prevention strategy in depression, the means by which suicide occurs must be a critical element of prevention. Policies that lower access to the means for suicide will decrease the fatality. Guns are associated with half of suicides and the case fatality rate of gun associated suicide is over 90% compared to 7% for all other means. This emphasizes the importance of offering strategies that limit access to guns to those at higher risk for suicide. A declaration of formal self-exclusion for access to firearms (guns and ammunition) offers the individual at greater risk for suicide to place themselves on an official list that would prevent them from purchasing lethal weapons. A person with depression, when well, might wish to enroll voluntarily to prevent themselves, when ill, from procuring a weapon to harm themselves or others. This recognizes the autonomy of the person and protects both the individual, the family, and society