Renewable energy power system at Swan Valley Nyungah Community: Industry or community innovation?

The paper presents a case study in renewable energy application, namely the renewable energy power system installed in the Swan Valley Nyungah Community (SVNC) in Perth, Western Australia. The objectives of the 1998 project, which involved the Perth based International Centre for Application of Solar Energy (CASE), were to provide electricity in a culturally acceptable form, reduce power costs and demonstrate the viability of the renewable energy technology used. The outcomes, however, did not match the expectations of the Aboriginal community or the Alternative Energy Development Board. The industry representatives did not have site specific knowledge for the implementation of their technology. The local end-users were not involved in the project itself. For projects like this to work, high professional responsibility, transparent accountability and community participation and acceptance of the technology should accompany good intentions

A survey of the views of program implementers on success factors of solar PV programs in Asia and the Pacific

Much effort has been invested in identifying the important barriers to the widespread take-up of renewable energy systems and in using information to develop best practice guidelines for the implementation of rural renewable energy electrification programs in developing countries. Many renewable electrification programs have been implemented in developing countries of Asia and the Pacific to improve the quality of life of the people living in remote rural areas. Those that have been successful demonstrate that a market for household renewable energy systems can be developed quickly and efficiently given the right combination of institutional, financial and policy instruments. The literature indicates, however, that a number of these programs have met with limited success. Much effort has been invested in attempting to identify the reasons behind this lack of success. Understanding the reasons behind the limited success of some programs, and for the relatively high success of others, is important as this information can inform program implementers and improve the success rates of future programs. Most of the research effort to date has focused on the identification of barriers to the widespread take-up of renewable energy systems and this information has been used in the development of best practice guidelines for the implementation of these programs. This narrow focus on barriers, however, does not consider other important factors behind the success of programs. An email survey of those implementing programs in SE Asian and Pacific countries was therefore undertaken with the aim of obtaining the views of program implementers on not only what barriers they see as hindering the uptake, but also on what essential factors they consider need to be included in designing and implementing programs in order ensure program success and the criteria to measure the program success

Efficient radiative transfer calculation and sensor performance requirements for the aerosol retrieval by airborne imaging spectroscopy

Detailed aerosol measurements in time and space are crucial to address open questions in climate research. Earth observation is a key instrument for that matter but it is biased by large uncertainties. Using airborne imaging spectroscopy, such as ESA's upcoming airborne Earth observing instrument APEX, allows determining the widely used aerosol optical depth (AOD) with unprecedented accuracy thanks to its high spatial and spectral resolution, optimal calibration and high signal-to-noise ratios (SNR). This study was carried out within the overall aim of developing such a tropospheric aerosol retrieval algorithm. Basic and efficient radiative transfer equations were applied to determine the sensor performance requirement and a sensitivity analysis in context of the aerosol retrieval. The AOD retrieval sensitivity requirement was chosen according to the demands of atmospheric correction processes. Therefore, a novel parameterization of the diffuse path-radiance was developed to simulate the atmospheric and surface effects on the signal at the sensor level. It was found for typical remote sensing conditions and a surface albedo of less than 30% that a SNR of circa 300 is sufficient to meet the AOD retrieval sensitivity requirement at 550nm. A surface albedo around 50% requires much more SNR, which makes the AOD retrieval very difficult. The retrieval performance is further analyzed throughout the visual spectral range for a changing solar geometry and different aerosol characteristics. As expected, the blue spectral region above dark surfaces and high aerosol loadings will provide the most accurate retrieval results. In general, the AOD retrieval feasibility could be proven for the analyzed cases for APEX under realistic simulated conditions

Measuring degree-degree association in networks

The Pearson correlation coefficient is commonly used for quantifying the global level of degree-degree association in complex networks. Here, we use a probabilistic representation of the underlying network structure for assessing the applicability of different association measures to heavy-tailed degree distributions. Theoretical arguments together with our numerical study indicate that Pearson's coefficient often depends on the size of networks with equal association structure, impeding a systematic comparison of real-world networks. In contrast, Kendall-Gibbons' $\tau_{b}$ is a considerably more robust measure of the degree-degree association

Clinically relevant concentrations of lidocaine and ropivacaine inhibit TNFα-induced invasion of lung adenocarcinoma cells in vitro by blocking the activation of Akt and focal adhesion kinase

BACKGROUND Matrix-metalloproteinases (MMP) and cancer cell invasion are crucial for solid tumour metastasis. Important signalling events triggered by inflammatory cytokines, such as tumour necrosis factor α (TNFα), include Src-kinase-dependent activation of Akt and focal adhesion kinase (FAK) and phosphorylation of caveolin-1. Based on previous studies where we demonstrated amide-type local anaesthetics block TNFα-induced Src activation in malignant cells, we hypothesized that local anaesthetics might also inhibit the activation and/or phosphorylation of Akt, FAK and caveolin-1, thus attenuating MMP release and invasion of malignant cells. METHODS NCI-H838 lung adenocarcinoma cells were incubated with ropivacaine or lidocaine (1 nM-100 µM) in absence/presence of TNFα (20 ng ml(-1)) for 20 min or 4 h, respectively. Activation/phosphorylation of Akt, FAK and caveolin-1 were evaluated by Western blot, and MMP-9 secretion was determined by enzyme-linked immunosorbent assay. Tumour cell migration (electrical wound-healing assay) and invasion were also assessed. RESULTS Ropivacaine (1 nM-100 μM) and lidocaine (1-100 µM) significantly reduced TNFα-induced activation/phosphorylation of Akt, FAK and caveolin-1 in NCI-H838 cells. MMP-9 secretion triggered by TNFα was significantly attenuated by both lidocaine and ropivacaine (half-maximal inhibitory concentration [IC50]=3.29×10(-6) M for lidocaine; IC50=1.52×10(-10) M for ropivacaine). The TNFα-induced increase in invasion was completely blocked by both lidocaine (10 µM) and ropivacaine (1 µM). CONCLUSIONS At clinically relevant concentrations both ropivacaine and lidocaine blocked tumour cell invasion and MMP-9 secretion by attenuating Src-dependent inflammatory signalling events. Although determined entirely in vitro, these findings provide significant insight into the potential mechanism by which local anaesthetics might diminish metastasi

Seasonal study of directional reflectance properties of snow

We present an analysis of the hemispherical-directional reflectance factor (HDRF) of snow, using 16 seasonal datasets of the spectral range from 400 to 2,500 nm. The data was measured under clear sky conditions in Davos Dorf (Grisons, Switzerland, 1,560 m a. s. l.). Fieldwork was carried out on seven days between February 5 and March 30 2004 with the Swiss Field Goniometer System (FIGOS). In addition to the HDRF measurements, snow stratigraphy, temperature and density were measured, and chemical and photomicroscopical analyses of snow samples were performed. Concentration of organic and elemental carbon was determined by chemical analysis. The grain size analyses through image processing of micrographs revealed relatively small differences of 0.21 to 0.33 mm mean radius in the top layers of snow cover. Seven datasets present HDRF of wet snow surfaces with similar anisotropy at smaller sun zenith angles (qI = 3.3 to 64.5°) compared to the nine surfaces measured at larger sun zenith angles (qI = 6.5 to 75.3°). Spectral albedo is relatively constant throughout datasets of different sun zenith angles of the same day, but has large variability among measurements of different days. With increasing wavelength, it decreases significantly faster for wet surfaces than for dry surfaces. The forward scattering peak was found to strengthen with increasing sun zenith angle and with increasing wavelength for both wet and dry surfaces at wavelengths above 700 nm. Finally, a spectral wet snow determination method is performed and the cross-sensitivity to HDRF variation could be derived. The best differentiability was found for 1,380 nm. This basis work increases the understanding of snow signatures for potential imaging spectroscopy applications in alpine regions

A scalable high-performance magnetic shield for very long baseline atom interferometry

We report on the design, construction, and characterization of a 10 m-long high-performance magnetic shield for very long baseline atom interferometry. We achieve residual fields below 4 nT and longitudinal inhomogeneities below 2.5 nT/m over 8 m along the longitudinal direction. Our modular design can be extended to longer baselines without compromising the shielding performance. Such a setup constrains biases associated with magnetic field gradients to the sub-pm/s2 level in atomic matterwave accelerometry with rubidium atoms and paves the way toward tests of the universality of free fall with atomic test masses beyond the 10-13 level. © 2020 Author(s)