Using collaborative virtual environments to plan wind energy installations

Countries around the world are introducing requirements to significantly increase their proportion of energy from renewable sources, such as wind. Poor siting or poor decision process will produce considerable local opposition delaying implementation and costing both proponents and the concerned public significant time, effort and stress. We propose that collaborative virtual environments have the advantage of allowing multiple involved parties to play out multiple planning scenarios and gather instant feedback in the process – ultimately with the goal of both effective energy generation and maintenance of local amenity. We have built a case study at the real wind turbine site of the Challicum Hills in Victoria, Australia. We use SIEVE (Spatial Information Exploration and Visualisation Environment) as a collaborative environment. SIEVE allows us to automatically build a virtual landscape model from the GIS data and then explore the model in 3D. Users get instant feedback about visible and audible impact (the simulation included attenuated wind turbine sounds). Edits can be performed in 3D and are saved into the GIS database. Finally, SIEVE allows collaborative planning where each participant can make and see changes and gather instant feedback on how these changes affect others (and if they meet resistance). Collaborative environments have the advantage that proposed changes are dynamic (compared to still images) and changes and feedback are directly linked (compared to an iterative planning process where planners develop plans without instant feedback).     

Update: offshore electrical installation practices

As the search for oil and gas progressed, platforms were located further offshore in deeper waters. This necessitated the requirement for offshore living quarters located on the platforms. Thus, the generation of electricity became a natural part of the scene on most platforms as the requirements grew to include cooking, heating and air conditioning, and lighting requirements for living quarters. This article discusses the development of electricity systems for offshore platforms form the 1950s to the 1990s. The development of the American Petroleum Institute's recommended practices (API RP) to cope with the unique design and installation requirements of the electrical systems is discussed. Revisions to the API RP 14F in the areas of power generating stations, distribution systems, electric motors, lighting, battery powered DC systems, and special systems are also discussed     

A silicon MEMS optical switch attenuator and its use in lightwavesubsystems

A single-mode fiber connectorized microelectromechanical systems (MEMS) reflective optical switch attenuator operating in the 1550-nm wavelength region is described. The device consists of an electrostatically actuated gold-coated silicon vane interposed in a fiber gap yielding 0.81-dB minimum insertion loss in the transmit state and high transmission isolation in the reflection state with 2.15-dB minimum return loss. The switch attenuators also work as continuously variable optical attenuators capable of greater than 50-dB dynamic range and can be accurately regulated with a simple feedback control circuit. Switching voltages were in the range of 5-40 V and a switching time of 64 μs was achieved. The MEMS switch can be used in optical subsystems within a wavelength-division-multiplexed (WDM) optical network such as optical power regulators, crossconnects, and add/drop multiplexers. We used a discrete array of 16 switch attenuators to implement a reconfigurable 16-channel 100-GHz spacing WDM drop module of an add/drop multiplexer. Thru-channel extinction was greater than 40 dB and average insertion loss was 21 dB. Both drop-and-transmit of multiple channels (11-18-dB contrast, 14-19-dB insertion loss) and drop-and-detect of single channels (>20-dB adjacent channel rejection, 10-14-dB insertion loss) were demonstrated     

Silicon/organic hybrid heterojunction infrared photodetector operating in the telecom regime

The authors report on the fabrication of a silicon/organic heterojunction based IR photodetector. It is demonstrated that an Al/p-Si/perylene-derivative/Al heterostructure exhibits a photovoltaic effect up to 2.7 μm (0.46 eV), a value significantly lower than the bandgap of either material. Although the devices are not optimized, at room temperature a rise time of 300 ns, a responsivity of ≈0.2 mA/W with a specific detectivity of D¹ ≈ 7 × 10⁷ Jones at 1.55 μm is found. The achieved responsivity is two orders of magnitude higher compared to our previous efforts [1], [2]. It will be outlined that the photocurrent originates from an absorption mechanism involving excitation of an electron from the Si valence band into the extended LUMO state in the perylene-derivative, with possible participation of intermediate localized surface state in the organic material.The non-invasive deposition of the organic interlayer onto the Si results in compatibility with the CMOS process, making the presented approach a potential alternative to all inorganic device concepts.     

Genetic and environmental influences on academic achievement trajectories during adolescence.

Most studies have considered the effects of particular characteristics on academic achievement individually, which means that little is known about how they function together. Using the population-based Minnesota Twin Family Study, the authors investigated the effects of child academic engagement (interest, involvement, effort), IQ, depression, externalizing behavior, and family environmental risk on academic achievement (reported school grades) from ages 11 through 17. Hierarchical linear growth curve modeling showed main effects on initial reported Grades for all variables, and IQ mitigated the deleterious effects of family risk and externalizing. Only engagement affected change in Grades through adolescence. Influences on initial Grades were strongly genetically influenced, associated primarily with IQ, engagement, and externalizing behavior. Shared environmental influences on initial Grades linked engagement, IQ, and family risk. Genetic influences on change in Grades were substantial, but they were not associated with the academic, family risk, and mental health covarying factors. These results indicate that age 11 achievement and change in achievement through adolescence show systematic patterns and document the existence of individual differences in the commonly shared developmental experience of adapting to the school environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic and environmental influences on personality trait stability and growth during the transition to adulthood: A three-wave longitudinal study.

During the transition to adulthood individuals typically settle into adult roles in love and work. This transition also involves significant changes in personality traits that are generally in the direction of greater maturity and increased stability. Competing hypotheses have been offered to account for these personality changes: The intrinsic maturation hypothesis suggests that change trajectories are endogenous, whereas the life-course hypothesis suggests that these changes occur because of transactions with the social environment. This study investigated the patterns and origins of personality trait changes from ages 17 to 29 using 3 waves of Multidimensional Personality Questionnaire data provided by twins. Results suggest that (a) trait changes were more profound in the first relative to the second half of the transition to adulthood; (b) traits tend to become more stable during the second half of this transition, with all the traits yielding retest correlations between .74 and .78; (c) Negative Affectivity declined over time, and Constraint increased over time; minimal change was observed on agentic or communal aspects of Positive Emotionality; and (d) both genetic and nonshared environmental factors accounted for personality changes. Overall, these genetically informed results support a life-course perspective on personality development during the transition to adulthood. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Phase I trial of docetaxel and cisplatin in previously untreated patients with advanced non-small-cell lung cancer

PURPOSE: To determine the maximum-tolerated doses (MTDs), principal toxicities, and pharmacokinetics of the combination of docetaxel and cisplatin administered every 3 weeks to patients with advanced non-small-cell lung cancer (NSCLC) who have not received prior chemotherapy and to recommend a dose for phase II studies. PATIENTS AND METHODS: Patients with advanced NSCLC and performance status 0 to 2 who had not received prior chemotherapy received docetaxel over 1 hour followed by cisplatin over 1 hour with hydration. Dose levels studied were (docetaxel/cisplatin) 50/75, 75/75, 75/100, and 100/75 mg/m2 repeated every 3 weeks. Colony-stimulating factor (CSF) support was not used. Pharmacokinetics of docetaxel and cisplatin were studied in the first cycle of therapy. Most patients (79%) had metastatic disease or intrathoracic recurrence after prior radiation and/or surgery. RESULTS: Of 24 patients entered, all were assessable for toxicity and 18 for response. The MTD schedules were docetaxel 75 mg/m2 with cisplatin 100 mg/m2 (dose-limiting toxicities [DLTs] in five of six patients), and docetaxel 100 mg/m2 with cisplatin 75 mg/m2 (DLTs in two of two patients, including one fatal toxicity). Limiting toxicities were febrile neutropenia and nonhematologic, principally diarrhea and renal. Two patients had neutropenic enterocolitis. Pharmacokinetics of both drugs were consistent with results from single-agent studies, which suggests no major pharmacokinetic interaction. Neutropenia was related to docetaxel area under the plasma concentration-versus-time curve (AUC). An alternative schedule was investigated, with cisplatin being administered over 3 hours commencing 3 hours after docetaxel, but toxicity did not appear to be less. Independently reviewed responses occurred in eight of 18 patients (44%; 95% confidence interval, 22% to 69%), most following 75 mg/m2 of both drugs. CONCLUSION: Docetaxel 75 mg/m2 over 1 hour followed by cisplatin 75 mg/m2 over 1 hour is recommended for phase II studies. The responses seen in this phase I study suggest a high degree of activity of this combination in previously untreated advanced NSCLC.     

A deubiquitinating enzyme that disassembles free polyubiquitin chains is required for development but not growth in Dictyostelium

Although cell differentiation usually involves synthesis of new proteins, little is known about the role of protein degradation. In eukaryotes, conjugation to ubiquitin polymers often targets a protein for destruction. This process is regulated by deubiquitinating enzymes, which can disassemble ubiquitin polymers or ubiquitin-substrate conjugates. We find that a deubiquitinating enzyme, UbpA, is required for Dictyostelium development. ubpA cells have normal protein profiles on gels, grow normally, and show normal responses to starvation such as differentiation and secretion of conditioned medium factor. However, ubpA cells have defective aggregation, chemotaxis, cAMP relay, and cell adhesion. These defects result from low expression of cAMP pulse-induced genes such as those encoding the cAR1 cAMP receptor, phosphodiesterase, and the gp80 adhesion protein. Treatment of ubpA cells with pulses of exogenous cAMP allows them to aggregate and express these genes like wild-type cells, but they still fail to develop fruiting bodies. Unlike wild type, ubpA cells accumulate ubiquitin-containing species that comigrate with ubiquitin polymers, suggesting a defect in polyubiquitin metabolism. UbpA has sequence similarity with yeast Ubp14, which disassembles free ubiquitin chains. Yeast ubp14 cells have a defect in proteolysis, due to excess ubiquitin chains competing for substrate binding to proteasomes. Cross-species complementation and enzyme specificity assays indicate that UbpA and Ubp14 are functional homologs. We suggest that specific developmental transitions in Dictyostelium require the degradation of specific proteins and that this process in turn requires the disassembly of polyubiquitin chains by UbpA.     

Hydrophobic forces dominate the thermodynamic characteristics of UvrA-DNA damage interactions

The Streptomyces coelicolor obg gene, which encodes a putative GTP-binding protein of the Obg/Gtp1 family, was characterized. The obg gene was essential for viability. Introduction of multiple copies of obg into wild-type S. coelicolor suppressed aerial mycelium formation. A single amino acid substitution at any of six positions was introduced into the GTP binding site of Obg, and the mutated proteins were expressed in wild-type cells. Obg(P168-->V) exerted a more accentuated suppressive effect on aerial mycelium formation than did the wild-type Obg protein. In contrast, Obg(G171-->A) accelerated the development of aerial mycelium. These results show that Obg protein functions as a pivotal regulator for the onset of cell differentiation through its ability to bind GTP. Western analysis revealed that expression of obg is regulated in a growth phase-dependent manner, indicating a sharp decrease just after onset of aerial mycelium development or at the end of vegetative growth. Obg was a membrane-bound protein as determined by immunoelectron microscopy.