Small is Possible by George McRobie and Small is Beautiful and Possible... But Access to Land is Critical by Robert A. Williams

On April 29 1982 George McRobie visited Simon Fraser University to deliver a lecture on his favourite topic - "appropriate" technology. To give special point to that occasion and underline the relevance of the topic for British Columbia Robert Williams was invited to give a counterpoint talk. This Siamese-twin paper is the result of that juxtaposition.  George McRobie spent some fifteen years with the National Coal Board in Britain, during which he was closely associated with E.F. Schumacher, author of Small is Beautiful. In 1965 they founded the Intermediate Technology Development Group in London, U .K., of which Mr. McRobie is now chairman. A graduate in economics of the London School of Economics Mr. McRohie is the author of Small is Possible. Robert A. Williams is best known in British Columbia for his political activities, especially as Minister of Lands, Forests and Water Resources in the NDP government from 1972 to 1975. Having degrees in economics and urban planning from the University of British Columbia he has a special interest in land issues

Multi-Gain-Stage InGaAs Avalanche Photodiode with Enhanced Gain and Reduced Excess Noise

We report the design, fabrication, and test of an InGaAs avalanche photodiode (APD) for 950-1650 nm wavelength sensing applications. The APD is grown by molecular beam epitaxy on InP substrates from lattice-matched InGaAs and InAlAs alloys. Avalanche multiplication inside the APD occurs in a series of asymmetric gain stages whose layer ordering acts to enhance the rate of electron-initiated impact ionization and to suppress the rate of hole-initiated ionization when operated at low gain. The multiplication stages are cascaded in series, interposed with carrier relaxation layers in which the electric field is low, preventing avalanche feedback between stages. These measures result in much lower excess multiplication noise and stable linear-mode operation at much higher avalanche gain than is characteristic of APDs fabricated from the same semiconductor alloys in bulk. The noise suppression mechanism is analyzed by simulations of impact ionization spatial distribution and gain statistics, and measurements on APDs implementing the design are presented. The devices employing this design are demonstrated to operate at linear-mode gain in excess of 6000 without avalanche breakdown. Excess noise characterized by an effective impact ionization rate ratio below 0.04 were measured at gains over 1000

Diverter AI based decision aid, phases 1 and 2

It was determined that a system to incorporate artificial intelligence (AI) into airborne flight management computers is feasible. The AI functions that would be most useful to the pilot are to perform situational assessment, evaluate outside influences on the contemplated rerouting, perform flight planning/replanning, and perform maneuver planning. A study of the software architecture and software tools capable of demonstrating Diverter was also made. A skeletal planner known as the Knowledge Acquisition Development Tool (KADET), which is a combination script-based and rule-based system, was used to implement the system. A prototype system was developed which demonstrates advanced in-flight planning/replanning capabilities

Fire-induced Carbon Emissions and Regrowth Uptake in Western U.S. Forests: Documenting Variation Across Forest Types, Fire Severity, and Climate Regions

The forest area in the western United States that burns annually is increasing with warmer temperatures, more frequent droughts, and higher fuel densities. Studies that examine fire effects for regional carbon balances have tended to either focus on individual fires as examples or adopt generalizations without considering how forest type, fire severity, and regional climate influence carbon legacies. This study provides a more detailed characterization of fire effects and quantifies the full carbon impacts in relation to direct emissions, slow release of fire-killed biomass, and net carbon uptake from forest regrowth. We find important variations in fire-induced mortality and combustion across carbon pools (leaf, live wood, dead wood, litter, and duff) and across low- to high-severity classes. This corresponds to fire-induced direct emissions from 1984 to 2008 averaging 4 TgC/yr and biomass killed averaging 10.5 TgC/yr, with average burn area of 2723 sq km/yr across the western United States. These direct emission and biomass killed rates were 1.4 and 3.7 times higher, respectively, for high-severity fires than those for low-severity fires. The results show that forest regrowth varies greatly by forest type and with severity and that these factors impose a sustained carbon uptake legacy. The western U.S. fires between 1984 and 2008 imposed a net source of 12.3 TgC/yr in 2008, accounting for both direct fire emissions (9.5 TgC/yr) and heterotrophic decomposition of fire-killed biomass (6.1 TgC yr1) as well as contemporary regrowth sinks (3.3 TgC/yr). A sizeable trend exists toward increasing emissions as a larger area burns annually

Combinations of isoform-targeted histone deacetylase inhibitors and bryostatin analogues display remarkable potency to activate latent HIV without global T-cell activation

AbstractCurrent antiretroviral therapy (ART) for HIV/AIDS slows disease progression by reducing viral loads and increasing CD4 counts. Yet ART is not curative due to the persistence of CD4+ T-cell proviral reservoirs that chronically resupply active virus. Elimination of these reservoirs through the administration of synergistic combinations of latency reversing agents (LRAs), such as histone deacetylase (HDAC) inhibitors and protein kinase C (PKC) modulators, provides a promising strategy to reduce if not eradicate the viral reservoir. Here, we demonstrate that largazole and its analogues are isoform-targeted histone deacetylase inhibitors and potent LRAs. Significantly, these isoform-targeted HDAC inhibitors synergize with PKC modulators, namely bryostatin-1 analogues (bryologs). Implementation of this unprecedented LRA combination induces HIV-1 reactivation to unparalleled levels and avoids global T-cell activation within resting CD4+ T-cells.</jats:p

Genome analysis of a highly virulent serotype 1 strain of streptococcus pneumoniae from West Africa

Streptococcus pneumoniae is a leading cause of pneumonia, meningitis, and bacteremia, estimated to cause 2 million deaths annually. The majority of pneumococcal mortality occurs in developing countries, with serotype 1 a leading cause in these areas. To begin to better understand the larger impact that serotype 1 strains have in developing countries, we characterized virulence and genetic content of PNI0373, a serotype 1 strain from a diseased patient in The Gambia. PNI0373 and another African serotype 1 strain showed high virulence in a mouse intraperitoneal challenge model, with 20% survival at a dose of 1 cfu. The PNI0373 genome sequence was similar in structure to other pneumococci, with the exception of a 100 kb inversion. PNI0373 showed only15 lineage specific CDS when compared to the pan-genome of pneumococcus. However analysis of non-core orthologs of pneumococcal genomes, showed serotype 1 strains to be closely related. Three regions were found to be serotype 1 associated and likely products of horizontal gene transfer. A detailed inventory of known virulence factors showed that some functions associated with colonization were absent, consistent with the observation that carriage of this highly virulent serotype is unusual. The African serotype 1 strains thus appear to be closely related to each other and different from other pneumococci despite similar genetic content

Clinical Significance of Sleep Desaturation in Hypoxemic Chronic Obstructive Pulmonary Disease: Studies in 130 Patients

We studied 130 patients with hypoxemic chronic obstructive lung disease to determine if nocturnal desaturation aggravates hypoxia-induced complications. All had tests of neuropsychological and physiological function known to be affected by chronic hypoxia. Of the 130 patients, 25 had complete polysomnography and 105 had their sleep judged visually and arterial oxygen saturation recorded continuously. Severe and mild desaturation groups were defined relative to the mean for both mean and maximal sleep desaturation, and the severity of waking complications were compared. No significant differences were noted between patients with mild and severe mean desaturation or maximal desaturation for hematocrit, neuropsychological tests, maximal exercise tolerance, or measures of quality of life. Waking pulmonary artery pressure did not differ significantly between patients with mild and severe mean desaturation or maximal desaturation, except in 20 patients with the most severe mean desaturation during sleep. We conclude that nocturnal desaturation does not aggravate hypoxia-induced complications in most patients who are chronically hypoxemic from chronic obstructive pulmonary disease

A Cross-Institutional Perspective of Pre Laboratory Activities in Undergraduate Chemistry

Pre-laboratory exercises may help reduce cognitive load in the laboratory, boost confidence, develop theoretical understanding and skills, and improve grades on assessment tasks. This study compared pre-laboratory activities at two institutions, Go8-1 and Go8-2, to evaluate which attributes of pre-laboratory activities were perceived by students to best prepare them for laboratory classes. Students were surveyed towards the end of their laboratory course, and were asked a series of Likert-style and open response questions. Factor analysis was used to construct three scales, incorporating items relating to performance and understanding, items relating to affective and personal laboratory experience, and items relating to requiring support with laboratory equipment. No difference between cohorts was observed between the two institutions regarding requiring support with equipment. While Go8-1 students rated performance and understanding more highly than Go8-2 students, the opposite result was observed for affective and personal factors. The factor analysis results and responses to the open response questions indicated that students felt most prepared for laboratory exercises when the pre-class activities touched upon all aspects of the laboratory class. It is recommended that quizzes and video be used in pre-laboratory activities, with these resources covering theory, aims, methods, calculations and data analysis