Embedded Sensors in the Landscape: Measuring On-site Plant Stress Factors

This paper investigates the production of low-cost environmental sensors to collect data on environmental factors influencing plant stress in designed landscapes. Parameters measured include soil moisture, humidity, temperature and solar exposure. A prototype sensor is constructed from available components and installed on a trial site in Sydney, Australia. Data received from the prototype sensor is integrated with a Landscape Information Model to provide ongoing post-occupancy feedback. Results indicate that such sensors are straightforward to assemble, and are cost effective. It is suggested that developing familiarity with this and other sensor applications has potential to improve landscape education and practice. Lack of uptake in the landscape professions is, as indicated by the literature, primarily resulting from lack of training and knowledge barriers. An implementation guide is proposed to address this gap

Simulation and Visualisation of Plant Growth Using a Functional-structural Model

This paper investigates the simulation of plant growth in a virtual model using a combination of computational techniques. Equations from the GreenLab model are used to calculate the quantity of new biomass produced through photosynthesis, while a modified space colonisation algorithm is used to describe geometric growth. The geometric model is used to calculate intercepted light, which is fed back to the production equation. This simulation-modelling approach is used to generate visualisations of plant growth under varying environmental conditions and in mixed communities. The macro and micro scale virtual environment influences plant architecture and development. Semi-realistic simulation of growth is achieved across a number of plant species with the possibility of further application. The species are selected from those installed at a trial project in Sydney, Australia. Maintenance pro-cesses such as pruning and coppicing are implemented in the dynamic growth model. Challenges include increasing computational complexity when plants are simulated on a large scale site, and cost to validate growth parameters from in-situ study of plants

Why lose weight? Reasons for seeking weight loss by overweight but otherwise healthy men

OBJECTIVE: To identify the reasons for seeking weight loss in overweight or obese but otherwise healthy men. DESIGN: Interviews, prior to intervention, with subjects who had volunteered to participate in a work-site-based weight loss study. SUBJECTS: Ninety-one overweight=obese male workers. Mean age 41, range 18 – 55 y, mean body mass index (BMI) 31.0, range 26.2 – 41.6 kg=m2. MEASUREMENTS: Anthropometric measurements; body weight and height. Body mass index calculated. A short interview using open questions to determine the individuals reason for seeking weight loss. RESULTS: The message that weight loss is beneficial to health for the overweight was recognized by all subjects regardless of BMI, and was reported as the main factor for attempting weight loss. Improved fitness and effects on appearance and well-being were reported half as often as the primary reason for weight loss. CONCLUSION: Overweight lay members of the public have accepted the health education message that weight loss can improve health. Overweight but otherwise healthy men who responded, of their own accord, to an electronic mail message offering help to lose weight did not regard obesity and overweight as primarily a cosmetic issue. This is still, however, important, especially to younger people

How Filaments are Woven into the Cosmic Web

Observations indicate galaxies are distributed in a filament-dominated web-like structure. Numerical experiments at high and low redshift of viable structure formation theories also show filament-dominance. We present a simple quantitative explanation of why this is so, showing that the final-state web is actually present in embryonic form in the overdensity pattern of the initial fluctuations, with nonlinear dynamics just sharpening the image. The web is largely defined by the position and primordial tidal fields of rare events in the medium, with the strongest filaments between nearby clusters whose tidal tensors are nearly aligned. Applications of the cosmic web theory to observations include probing cluster-cluster bridges by weak gravitational lensing, X-rays, and the Sunyaev-Zeldovich effect and probing high redshift galaxy-galaxy bridges by low column density Lyman alpha absorption lines.Comment: 9 pages, gzipped uuencoded postscript file, 4 figures in separate files. The text + figures are also available from anonymous ftp site: ftp://ftp.cita.utoronto.ca/ftp/cita/bond/bkp_natur

Patient-maintained sedation for oral surgery using a target-controlled infusion of propofol - a pilot study

OBJECTIVE: To assess the safety and efficacy of a new patient-maintained propofol system for conscious sedation in dentistry. DESIGN: Prospective clinical trial SETTING: Department of Sedation, Glasgow Dental Hospital and School, 2001 SUBJECTS AND METHODS: Patients scheduled for oral surgery with conscious sedation. Exclusions included ASA IV -V, inability to use the handset, opioid use and severe respiratory disease. INTERVENTIONS: Patients were given intravenous propofol to a level of 1.0 microg/ml (reducing from 1.5 microg/ml) using a target controlled infusion system, they then controlled their sedation level by double-clicking a handset which on each activation increased the propofol concentration by 0.2 microg/ml. MAIN OUTCOME MEASURES: Oxygen saturation, patient satisfaction, and surgeon satisfaction. RESULTS: Twenty patients were recruited, 16 female and four male. Nineteen patients completed sedation and treatment successfully. Mean lowest oxygen saturation was 94%. No patients were over-sedated. All patients successfully used the system to maintain a level of sedation adequate for their comfort. Patient and surgeon satisfaction were consistently high. CONCLUSIONS: Initial experience with this novel system has confirmed safety, patient satisfaction and surgeon satisfaction

Assessing methods for dealing with treatment switching in randomised controlled trials: a simulation study

<p>Abstract</p> <p>Background</p> <p>We investigate methods used to analyse the results of clinical trials with survival outcomes in which some patients switch from their allocated treatment to another trial treatment. These included simple methods which are commonly used in medical literature and may be subject to selection bias if patients switching are not typical of the population as a whole. Methods which attempt to adjust the estimated treatment effect, either through adjustment to the hazard ratio or via accelerated failure time models, were also considered. A simulation study was conducted to assess the performance of each method in a number of different scenarios.</p> <p>Results</p> <p>16 different scenarios were identified which differed by the proportion of patients switching, underlying prognosis of switchers and the size of true treatment effect. 1000 datasets were simulated for each of these and all methods applied. Selection bias was observed in simple methods when the difference in survival between switchers and non-switchers were large. A number of methods, particularly the AFT method of Branson and Whitehead were found to give less biased estimates of the true treatment effect in these situations.</p> <p>Conclusions</p> <p>Simple methods are often not appropriate to deal with treatment switching. Alternative approaches such as the Branson & Whitehead method to adjust for switching should be considered.</p

Switchable pi-coordination and C-H metallation in small-cavity macrocyclic uranium and thorium complexes

New, conformationally restricted ThIV and UIV complexes, [ThCl2(L)] and [UI2(L)], of the small-cavity, dipyrrolide, dianionic macrocycle trans-calix[2]benzene[2]pyrrolide (L)2− are reported and are shown to have unusual κ5:κ5 binding in a bent metallocene-type structure. Single-electron reduction of [UI2(L)] affords [UI(THF)(L)] and results in a switch in ligand binding from κ5-pyrrolide to η6-arene sandwich coordination, demonstrating the preference for arene binding by the electron-rich UIII ion. Facile loss of THF from [UI(THF)(L)] further increases the amount of U–arene back donation. [UI(L)] can incorporate a further UIII equivalent, UI3, to form the very unusual dinuclear complex [U2I4(L)] in which the single macrocycle adopts both κ5:κ5 and η6:κ1:η6:κ1 binding modes in the same complex. Hybrid density functional theory calculations carried out to compare the electronic structures and bonding of [UIIII(L)] and [UIII2I4(L)] indicate increased contributions to the covalent bonding in [U2I4(L)] than in [UI(L)], and similar U–arene interactions in both. MO analysis and QTAIM calculations find minimal U–U interaction in [U2I4(L)]. In contrast to the reducible U complex, treatment of [ThCl2(L)] with either a reductant or non-nucleophilic base results in metallation of the aryl rings of the macrocycle to form the (L−2H)4− tetraanion and two new and robust Th–C bonds in the –ate complexes [K(THF)2ThIV(μ-Cl)(L−2H)]2 and K[ThIV{N(SiMe3)2}(L−2H)]

Genetic variation for tuber mineral concentrations in accessions of the Commonwealth Potato Collection

The variation in tuber mineral concentrations amongst accessions of wild tuber-bearing Solanum species in the Commonwealth Potato Collection (CPC) was evaluated under greenhouse conditions. Selected CPC accessions, representing the eco-geographical distribution of wild potatoes, were grown to maturity in peat-based compost under controlled conditions. Tubers from five plants of each accession were harvested, bulked and their mineral composition analysed. Among the germplasm investigated, there was a greater range in tuber concentrations of some elements of nutritional significance to both plants and animals, such as (Ca, Fe and Zn; 6.7, 3.6, and 4.5-fold respectively) than others, such as (K, P and S; all <3-fold). Significant positive correlations were found between mean altitude of the species' range and tuber P, K, Cu and Mg concentrations. The amount of diversity observed in the CPC collection indicates the existence of wide differences in tuber mineral accumulation among different potato accessions. This might be useful in breeding for nutritional improvement of potato tubers

Rectal Transmission of Transmitted/Founder HIV-1 Is Efficiently Prevented by Topical 1% Tenofovir in BLT Humanized Mice

Rectal microbicides are being developed to prevent new HIV infections in both men and women. We focused our in vivo preclinical efficacy study on rectally-applied tenofovir. BLT humanized mice (n = 43) were rectally inoculated with either the primary isolate HIV-1(JRCSF) or the MSM-derived transmitted/founder (T/F) virus HIV-1(THRO) within 30 minutes following treatment with topical 1% tenofovir or vehicle. Under our experimental conditions, in the absence of drug treatment we observed 50% and 60% rectal transmission by HIV-1(JRCSF) and HIV-1(THRO), respectively. Topical tenofovir reduced rectal transmission to 8% (1/12; log rank p = 0.03) for HIV-1(JRCSF) and 0% (0/6; log rank p = 0.02) for HIV-1(THRO). This is the first demonstration that any human T/F HIV-1 rectally infects humanized mice and that transmission of the T/F virus can be efficiently blocked by rectally applied 1% tenofovir. These results obtained in BLT mice, along with recent ex vivo, Phase 1 trial and non-human primate reports, provide a critically important step forward in the development of tenofovir-based rectal microbicides