Broughton Archipelago Clam Terrace Survey : final report

During a 1995 aerial video survey of the coastline of Johnstone Strait, an unusual shoreline feature was noted and termed “clam terraces” (inset) because of the terrace-type morphology and the apparent association with high clam productivity on the sandflats. Typical alongshore lengths of the terrace ridges are 20-50m, and across-shore widths are typically 20-40m. An area with an especially high density of clam terraces was noted in the Broughton Archipelago, between Broughton and Gilford Islands of southeastern Queen Charlotte Strait. Clam terraces in this area were inventoried from the aerial video imagery to quantify their distribution. The terraces accounted for over 14 km of shoreline and 365 clam terraces were documented. A three-day field survey by a coastal geomorphologist, archeologist and marine biologist was conducted to document the features and determine their origin. Nine clam terraces were surveyed. The field observations confirmed that: the ridges are comprised of boulder/cobblesized material, ridge crests are typically in the range of 1-1.5m above chart datum, sandflats are comprised almost entirely of shell fragments (barnacles and clams) and sandflats have very high shellfish production. There are an abundance of shell middens in the area (over 175) suggesting that the shellfish associated with the terraces were an important food source of aboriginal peoples. The origin of the ridges is unknown; they appear to be a relict feature in that they are not actively being modified by present-day processes. The ridges may be a relict sea-ice feature, although the mechanics of ridge formation is uncertain. Sand accumulates behind the ridge because the supply rate of the shell fragments exceeds the dispersal rate in these low energy environments. The high density areas of clam terraces correspond to high density areas of shell middens, and it is probable that the clam terraces were subjected to some degree of modification by aboriginal shellfish gatherers over the thousands of years of occupation in the region. (Document contains 39 pages

A Chromosomal Deletion and New Frameshift Mutation Cause ARSACS in an African-American

Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay (ARSACS) is a rare, progressive, neurodegenerative disease characterized by ataxia, spasticity and polyneuropathy. First described in the French-Canadian population of Quebec in 1978, ARSACS has since been identified in multiple patients worldwide. In this clinical case report, we describe the evaluation of an 11-years-old African-American male who presented to neuromuscular clinic for assessment of a gait abnormality. He had a history of gross motor delay since early childhood, frequent falls and a below average IQ. Chromosomal microarray revealed a 1.422 megabase loss in the 13q12.12 region, which includes the SACS gene. Next Generation Sequencing then showed a novel, predicted to be pathogenic missense mutation (c.11824dup) of this gene. His clinical presentation and neurological imaging further confirmed the diagnosis of ARSACS. To our knowledge, this is the first reported case of this disease in the African-American population of the United States. This case report further highlights the growing trend of identifying genetic diseases previously restricted to single, ethnically isolated regions in many different ethnic groups worldwide

Chromatic transit light curves of disintegrating rocky planets

Context. Kepler observations have revealed a class of short period exoplanets, of which Kepler-1520 b is the prototype, which have comet-like dust tails thought to be the result of small, rocky planets losing mass. The shape and chromaticity of the transits constrain the properties of the dust particles originating from the planet's surface, offering a unique opportunity to probe the composition and geophysics of rocky exoplanets. Aims. We aim to approximate the average Kepler long-cadence light curve of Kepler-1520 b and investigate how the optical thickness and transit cross-section of a general dust tail can affect the observed wavelength dependence and depth of transit light curves. Methods. We developed a new 3D model that ejects sublimating particles from the planet surface to build up a dust tail, assuming it to be optically thin, and used 3D radiative transfer computations that fully treat scattering using the distribution of hollow spheres (DHS) method, to generate transit light curves between 0.45 and 2.5 $\mu$m. Results. We show that the transit depth is wavelength independent for optically thick tails, potentially explaining why only some observations indicate a wavelength dependence. From the 3D nature of our simulated tails, we show that their transit cross-sections are related to the component of particle ejection velocity perpendicular to the planet's orbital plane and use this to derive a minimum ejection velocity of 1.2 kms$^{-1}$. To fit the average transit depth of Kepler-1520 b of 0.87%, we require a high dust mas-loss rate of 7 $-$ 80 M$_\oplus$ Gyr$^{-1}$ which implies planet lifetimes that may be inconsistent with the observed sample. Therefore, these mass-loss rates should be considered to be upper limits.Comment: 22 pages, 22 figures, accepted for publication in A&

Evaluating the Effectiveness of an Established Community-Based Eccentric Viewing Rehabilitation Training Model—the EValuation Study

Purpose: This study evaluated the community-based eccentric viewing (EV) training offered across the United Kingdom by the Macular Society. Volunteer trainers deliver free one-to-one training, usually in learners' homes. They also share information about lighting, magnification, social support, and low-vision technology. Methods: The audio-recorded reading performance of learners was compared before and after training. Telephone questionnaires were used to assess life satisfaction, amount of reading performed, and health- and vision-related quality of life. Learners were also interviewed to obtain their subjective opinions. Results: A total of 121 learners completed all stages of the study. There was no significant change in maximum reading speed. A statistically significant (P < 0.001) but small improvement in both critical print size and threshold print size was found, but frequency and duration of reading did not increase. There was a borderline significant (P = 0.022) increase in “life satisfaction” for the learners, but a highly significant (P < 0.001) decrease in their “positive affect.” There was no change in health- or vision-related quality of life, or in the difficulty experienced in performing everyday tasks. However, according to learner interviews, 72% felt they had achieved a positive outcome from the training, and 75% felt they had received helpful advice in addition to the EV training. Conclusions: The lack of improvement of reading speed and modest improvement in threshold print size should be interpreted in the context of the unique features of this EV program, since many learners who would seem to have limited scope for improvement still undertake the training

Evaluating the effectiveness of the Macular Society Eccentric Viewing Rehabilitation Training - the evaluation study

Background: The Macular Society have provided Eccentric Viewing (EV) training across the UK since 2006, by training volunteers to deliver a community based model. Trainers deliver free one-to-one training during 1-3, 1 hour over a 2–3 month period, usually in learners’ homes. During sessions, trainers also share handy hints and tips about (e.g.) lighting, magnification, social support and technology. Methods: An independent research team evaluated the effectiveness of the programme using a wide range of outcome measures, including reading ability; well-being; and health- and vision-related quality of life. Learners were also interviewed for their opinions. Results: 121 learners completed all stages of the study. They perceived the trainers to be knowledgeable, well- trained and friendly. 75% of learners felt they had received helpful advice in addition to EV training; and 65% of learners felt they had achieved a positive outcome. Objective results were less encouraging. There was a borderline significant increase in “life satisfaction” for the learners, but a highly significant decrease in their “positive affect” (PANAS). There was no significant change in measured reading speed or acuity (MNRead-style test); or in health- or vision-related quality of life (EQ-5D-5L; VisQoL; NEI-VFQ-7). There was, however, an increase in the proportion of learners reporting that they could read a newspaper with “little or no difficulty” (from 13% to 23%); and a significant decrease in the number reporting “extreme difficulty” whilst watching television (from 27% to 15%). Conclusion: The findings may be explained by some of the unique features of this programme: many learners who would seem to have limited scope for improvement still wish to undertake the training; the interval between training sessions is lengthy; and there is no link to a low vision assessment. Acknowledgements: Commissioned and funded by the Macular Society

Disposal of Household Wastewater in Soils of High Stone Content (1981-1983)

Four experimental filter fields were constructed with built-in monitoring equipment in Nixa soils. These soils contain many chert fragments and a fragipan about 60 cm below the soil surface. The fragipan restricts downward movement of water and is the designlimitingfeature. The four filter fields were: 1. A standard filter field, 76 cm deep. The bottom of the trench was in the fragipan. 2. A modified standard filter field, 30 cm deep. The bottom of the trench was above the fragipan. 3. A modified pressure filter field, 40 cm deep. The bottom of the trench was above the fragipan. In addition, a pressure-distribution system was used to insure uniform distribution of effluent in the trench. Inadvertently, this field was installed in a different soil, and the results cannot be compared directly with the other three. 4. Another modified pressure filter field with the bottom of the trench only 6 cm below the soil surface. Observation of these systems confirms that placing filter fields higher in the soil above the hydraulically limiting horizon results in improved hydraulic performance. The presence of the fragipan amplified the adverse effects attributable to climatic stress. The seepage beds which are higher in the soil profile are able to handle the effluent load and climate load with less danger of surfacing

Generating Bijections between HOAS and the Natural Numbers

A provably correct bijection between higher-order abstract syntax (HOAS) and the natural numbers enables one to define a "not equals" relationship between terms and also to have an adequate encoding of sets of terms, and maps from one term family to another. Sets and maps are useful in many situations and are preferably provided in a library of some sort. I have released a map and set library for use with Twelf which can be used with any type for which a bijection to the natural numbers exists. Since creating such bijections is tedious and error-prone, I have created a "bijection generator" that generates such bijections automatically together with proofs of correctness, all in the context of Twelf.Comment: In Proceedings LFMTP 2010, arXiv:1009.218

Transoral Approach to Excision of Massive Dermoid Cysts in Pediatric Patients: A Case Series

Floor of mouth (FOM) dermoid cysts are a rare but clinically significant lesion of the head and neck. Classically, large cysts have been excised via a transcervical approach, although the limits of the transoral approach are expanding. The majority of FOM dermoid cysts present in the midline, but true lateral cysts have been reported. In this case series, we describe 3 pediatric patients who all underwent successful transoral excision of massive dermoid cysts, along with a literature review. Massive cystic lesions were identified on preoperative imaging. The dermoid cysts averaged 6 × 4.3 × 5 cm and were successfully removed via a transoral approach. Two were removed via a median ventral FOM incision and one via a lateral trans-sublingual approach to the FOM. When needed, the geniohyoid muscle was divided to gain access to the cyst. All cysts were removed intact, although partial, controlled decompression was performed to aid in dissection. There were no post-operative complications. FOM dermoid cysts are a rare but important cause of pediatric neck masses that present a challenging but satisfying surgical opportunity. The transoral approach is a viable option for massive dermoid cysts superior to the mylohyoid