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Given increasing investments in ecological restoration around the globe, there is a need to develop standards of practice to improve professional training and encourage the highest quality of performance possible. Although professional certification is a mechanism for promoting and improving the profession, until now certification has not been available to individuals who practice ecological restoration. The Society for Ecological Restoration (SER) is launching a professional certification program in early 2017. The program requires professional experience, a knowledge base in five broad subject areas, understanding of the foundations of the profession, and adherence to a code of ethics. The SER certification program will certify both practitioners (Certified Ecological Restoration Practitioners [CERPs]) and practitioners-in-training (Certified Ecological Restoration Practitioners-in-training [CERPITs]). [ABSTRACT FROM AUTHOR]

Purpose: A novel 169Yb low dose rate permanent implant brachytherapy source, the GammaClip™, was developed by Source Production & Equipment Co. (New Orleans, LA) which is designed similar to a surgical staple while delivering therapeutic radiation. In this report, the brachytherapy source was characterized in terms of 'Dose calculation for photon-emitting brachytherapy sources with average energy higher than 50 keV: Report of the AAPM and ESTRO' by Perez-Calatayud et al. [Med. Phys. 39, 2904-2929 (2012)] using the updated AAPM Task Group Report No. 43 formalism. Methods: Monte Carlo calculations were performed using Monte Carlo N-Particle 5, version 1.6 in water and air, the in-air photon spectrum filtered to remove photon energies below 10 keV in accordance with TG-43U1 recommendations and previously reviewed 169Yb energy cutoff levels [D. C. Medich, M. A. Tries, and J. M. Munro, 'Monte Carlo characterization of an Ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty,' Med. Phys. 33, 163-172 (2006)]. TG-43U1 dosimetric data, including SK, D(r,θ), Λ, gL(r), F(r, θ), [lowercase_phi_synonym]an(r), and [lowercase_phi_synonym]an were calculated along with their statistical uncertainties. Since the source is not axially symmetric, an additional set of calculations were performed to assess the resulting axial anisotropy. Results: The brachytherapy source's dose rate constant was calculated to be (1.22 ± 0.03) cGy h-1 U-1. The uncertainty in the dose to water calculations, D(r,θ), was determined to be 2.5%, dominated by the uncertainties in the cross sections. The anisotropy constant, [lowercase_phi_synonym]an, was calculated to be 0.960 ± 0.011 and was obtained by integrating the anisotropy factor between 1 and 10 cm using a weighting factor proportional to r-2. The radial dose function was calculated at distances between 0.5 and 12 cm, with a maximum value of 1.20 at 5.15 ± 0.03 cm. Radial dose values were fit to a fifth order polynomial and dual exponential regression. Since the source is not axially symmetric, angular Monte Carlo calculations were performed at 1 cm which determined that the maximum azimuthal anisotropy was less than 8%. Conclusions: With a higher photon energy, shorter half-life and higher initial dose rate 169Yb is an interesting alternative to 125I for the treatment of nonsmall cell lung cancer. [ABSTRACT FROM AUTHOR]

Purpose: To study the effects of the breast-air and breast-lung interfaces on the absorbed dose within the planning target volume (PTV) of a MammoSite® balloon dose delivery system as well as the effect of contrast material on the dose rate in the PTV. Methods: The Monte Carlo MCNP5 code was used to simulate dose rate in the PTV of a 2 cm radius MammoSite® balloon dose delivery system. The simulations were carried out using an average female chest phantom (AFCP) and a semi-infinite water phantom for both Yb-169 and Ir-192 high dose rate sources for brachytherapy application. Gastrografin was introduced at varying concentrations to study the effect of contrast material on the dose rate in the PTV. Results: The effect of the density of the materials surrounding the MammoSite® balloon containing 0% contrast material on the calculated dose rate at different radial distances in the PTV was demonstrated. Within the PTV, the ratio of the calculated dose rate for the AFCP and the semi-infinite water phantom for the point closest to the breast-air interface (90°) is less than that for the point closest to the breast-lung interface (270°) by 11.4% and 4% for the HDR sources of Yb-169 and Ir-192, respectively. When contrast material was introduced into the 2 cm radius MammoSite® balloon at varying concentrations, (5%, 10%, 15%, and 20%), the dose rate in the AFCP at 3.0 cm radial distance at 90° was decreased by as much as 14.8% and 6.2% for Yb-169 and Ir-192, respectively, when compared to that of the semi-infinite water phantom with contrast concentrations of 5%, 10%, 15%, and 20%, respectively. Conclusions: Commercially available software used to calculate dose rate in the PTV of a MammoSite® balloon needs to account for patient anatomy and density of surrounding materials in the dosimetry analyses in order to avoid patient underdose. [ABSTRACT FROM AUTHOR]

Purpose: Absorbed dose energy correction factors, used to convert the absorbed dose deposited in a LiF thermoluminescent dosimeter (TLD) into the clinically relevant absorbed dose to water, were obtained for both spherical volumetric sources and for the model 4140 HDR Yb-169 source. These correction factors have a strong energy dependence below 200 keV; therefore, spectral changes were quantified as Yb-169 photons traveled through both source material (Yb2O3) and water with the corresponding absorbed dose energy correction factors, f(r,θ), calculated as a function of location in a phantom. Methods: Using the MCNP5 Monte Carlo radiation transport simulation program, the Yb-169 spectrum emerging from spherical Yb2O3 sources (density 6.9 g/cm3) with radii between 0.2 and 0.9 mm were analyzed and their behavior compared against those for a point-source. The absorbed dose deposited to both LiF and H2O materials was analyzed at phantom depths of 0.1–10 cm for each source radius and the absorbed dose energy correction factor calculated as the ratio of the absorbed dose to water to that of LiF. Absorbed dose energy correction factors for the Model 4140 Yb-169 HDR brachytherapy source similarly were obtained and compared against those calculated for the Model M-19 Ir-192 HDR source. Results: The Yb-169 average spectral energy, emerging from Yb2O3 spherical sources 0.2–0.9 mm in radius, was observed to harden from 7% to 29%; as these photons traveled through the water phantom, the photon average energy softened by as much as 28% at a depth of 10 cm. Spectral softening was dependent on the measurement depth in the phantom. Energy correction factors were found to vary both as a function of source radius and phantom depth by as much as 10% for spherical Yb2O3 sources. The Model 4140 Yb-169 energy correction factors depended on both phantom depth and reference angle and were found to vary by more than 10% between depths of 1 and 10 cm and angles of 0° and 180°. This was in contrast to that of the Model M-19 Ir-192 source which exhibited approximately 3.5%–4.4% variation in its energy correction factors from phantom depths of 0.5–10 cm. The absorbed dose energy correction factor for the Ir-192 source, on the other hand, was independent of angle to within 1%. Conclusions: The application of a single energy correction factor for Yb-169 TLD based dosimetry would introduce a high degree of measurement uncertainty that may not be reasonable for the clinical characterization of a brachytherapy source; rather, an absorbed dose energy correction function will need to be developed for these sources. This correction function should be specific to each source model, type of TLD used, and to the experimental setup to obtain accurate and precise dosimetric measurements. [ABSTRACT FROM AUTHOR]

Radiochromic film dosimetry has been extensively used for intravascular brachytherapy applications for near field within 1 cm from the sources. With the recent introduction of new model of radiochromic films, GAFCHROMIC® EBT, with higher sensitivity than earlier models, it is promising to extend the distances out to 5 cm for low dose rate (LDR) source dosimetry. In this study, the use of new model GAFCHROMIC® EBT film for 125I seed dosimetry in Solid Water® was evaluated for radial distances from 0.06 cm out to 5 cm. A multiple film technique was employed for four 125I seeds (Implant Sciences model 3500) with NIST traceable air kerma strengths. Each experimental film was positioned in contact with a 125I seed in a Solid Water® phantom. The products of the air kerma strength and exposure time ranged from 8 to 3158 U-h, with the initial air kerma strength of 6 U in a series of 25 experiments. A set of 25 calibration films each was sequentially exposed to one 125I seed at about 0.58 cm distance for doses from 0.1 to 33 Gy. A CCD camera based microdensitometer, with interchangeable green (520 nm) and red (665 nm) light boxes, was used to scan all the films with 0.2 mm pixel resolution. The dose to each 125I calibration film center was calculated using the air kerma strength of the seed (incorporating decay), exposure time, distance from seed center to film center, and TG43U1S1 recommended dosimetric parameters. Based on the established calibration curve, dose conversion from net optical density was achieved for each light source. The dose rate constant was determined as 0.991 cGy U-1 h-1 (±6.9%) and 1.014 cGy U-1 h-1 (±6.8%) from films scanned using green and red light sources, respectively. The difference between these two values was within the uncertainty of the measurement. Radial dose function and 2D anisotropy function were also determined. The results obtained using the two light sources corroborated each other. We found good agreement with the TG43U1S1 recommended values of radial dose function and 2D anisotropy function, to within the uncertainty of the measurement. We also verified the dosimetric parameters in the near field calculated by Rivard using Monte Carlo method. The radial dose function values in Solid Water® were lower than those in water recommended by TG43U1S1, by about 2%, 3%, 7%, and 14% at 2, 3, 4, and 5 cm, respectively, partially due to the difference in the phantom material composition. Radiochromic film dosimetry using GAFCHROMIC® EBT model is feasible in determining 2D dose distributions around low dose rate 125I seed. It is a viable alternative to TLD dosimetry for 125I seed dose characterization. [ABSTRACT FROM AUTHOR]

The MCNP5 Monte Carlo code was used to simulate the dosimetry of an M-19 iridium-192 high dose rate brachytherapy source in both air/vacuum and water environments with the in-air photon spectrum filtered to remove low-energy photons below δ=10 keV. Dosimetric data was organized into an away-along table and was used to derive the updated AAPM Task Group Report No. 43 (TG-43U1) parameters including SK, D(r,θ), Λ, gL(r), F(r,θ), [lowercase_phi_synonym]an(r), and [lowercase_phi_synonym]an and their respective statistical uncertainties. [ABSTRACT FROM AUTHOR]

From the seventeenth century, the world's finest wools have been those produced by descendants of the Spanish merino. During the middle ages, however, England produced Europe's finest wools. Not until the fourteenth century does a distinct merino breed appear in Spain; and, before then, 'Spanish' wools were amongst the very worst in Europe, used in the production of only the very cheapest fabrics. By the late fourteenth century, some merino wools were being used in some Italian draperies; but, in the north, long‐held historic prejudices against 'Spanish' wools hindered their introduction, especially into the Low Countries' draperies, which, because of structural changes in international trade, had become re‐oriented to manufacturing luxury woollens, most woven from the finest English wools. From the 1420s, however, disastrous changes in England's fiscal policies so increased the cost of these exported wools that many of the younger Flemish draperies, the so‐called nouvelles draperies, producing imitations of the finer woollens from the older established draperies, decided to switch to Spanish merino wools (often mixed with English wools). By the mid‐fifteenth century, the merinos had indeed improved enough in quality to rival at least the mid‐range English wools. Most of the traditional draperies, however, did not adopt merino wools until much too late, and thus, by the early sixteenth century found themselves displaced by the nouvelle draperies as the leading cloth manufacturers in the Low Countries. [ABSTRACT FROM AUTHOR]

Books reviewed:Michael W. Klein, Scott Schuh, and Robert K. Triest,Job Creation, Job Destruction, and International CompetitionCarl Davidson and Steven J. Matusz,International Trade and Labor Markets: Theory, Evidence, and Policy ImplicationsWilliam R. Black,Transportation: A Geographical AnalysisBernard Fingleton,European Regional GrowthBernard Fingleton, Ayda Eraydin, and Raffaele Paci,Regional Growth, SMEs and the Wider EuropeJulia Traistaru, Peter Nijkamp, and Laura Resmini,The Emerging Economic Geography in EU Accession CountriesJohannes Bröcker, Dirk Dohse, and Rüdiger Soltwedel,Innovation Clusters and Interregional CompetitionAlan Hyde,Working in Silicon Valley: Economic and Legal Analysis of a High-Velocity Labor MarketRobert Mark Silverman,Community-Based Organizations: The Intersection of Social Capital and Local Context in Contemporary Urban SocietyWilliam A. V. Clark,Immigrants and the American Dream: Remaking the Middle ClassBarry G. Rabe,Statehouse and Greenhouse: The Emerging Politics of American Climate Change PolicyAmrita Daniere and Lois M. Takahashi,Rethinking Environmental Management in the Pacific Rim: Exploring Local Participation in Bangkok, ThailandCenter for Sustainable Environments, Northern Arizona University, with Terralingua and Grand Canyon Wildlands Council,Safeguarding the Uniqueness of the Colorado Plateau: An Ecoregional Assessment of Biocultural Diversity [ABSTRACT FROM AUTHOR]

The Yellow-faced Honeyeater Lichenostomus chrysops is a diurnal migrant which covers short to moderate distances in eastern Australia. Recordings of locomotor activity of nine wild-caught Yellow-faced Honeyeaters kept under a simulated natural photoperiod in the laboratory over a period of 13 months showed that these birds exhibit a distinct seasonal pattern in hopping activity. Two major seasonal peaks of enhanced activity were observed. The first occurred during the time of autumn migration in March to July, while a second peak from September to December coincided roughly with spring migration. Daily activity patterns of Yellow-faced Honeyeaters showed two major peaks. The first peak ranged from the early morning hours to approximately early afternoon, while a second smaller peak was observed in the late afternoon. During their migratory periods in spring and autumn, the morning as well as the afternoon peaks were considerably higher than in months when Yellow-faced Honeyeaters do not migrate. [ABSTRACT FROM AUTHOR]

Background. Cognitive style has been shown to influence several areas of academic learning. Aims. This study examines the influence of one aspect of cognitive style, the verbal-imagery dimension, on the ability to learn to write a specific type of text, the letter of complaint, taught using genre-based teaching procedures. Samples. A group of 41 post-compulsory secondary school students (23 females and 18 males) aged between 15 years 6 months and 16 years 9 months. Methods. The study employed a time series design in which the influence of cognitive style on acquiring components of the text type was monitored during learning. Students wrote letters of complaint under six conditions that matched genre-based teaching procedures; pre- and immediately post exposure to teaching, retention and transfer with and without access to exemplary models of the genre. Prior to involvement, students were assessed as displaying either a verbal, imagery or medial cognitive preference. Results. Cognitive style influenced learning the text type only when there was access to models of it; verbal preferrers used these models better than the imagery preferrers. This influence was greatest for the components of the letter associated with a knowledge of verbal conventions. As well, its influence was greater during the initial learning than on its long term retention. Conclusions. The findings suggest that, in learning to write a genre, cognitive style has a greater influence on the processing of the information presented during teaching than on its long term retention. [ABSTRACT FROM AUTHOR]

Presents information on a study which examined the allocation of British Columbia highway expenditures among electoral districts over the period 1954 to 1969. Advantages of highway expenditure analysis as an avenue for exploring the interaction of economic and political variables in government decision-making; Details of a model for highway expenditure allocation analysis; Political influence in highway expenditures.