The Design, Construction and Commissioning of a Small Scale Dynamic Calibrated Hot Box (CHB)

Sustainable construction and in particular the sustainability of materials is a global issue with legislation on material properties and product performance at the forefront. In traditional constructed buildings however, it can be extremely challenging to get accurate data on performance. The variability of building materials design, manufacture and construction from different eras is substantial, even within local areas due to the vernacular nature of construction from these periods. Material properties testing can be expensive and is not always readily available when required and is therefore often ignored, particularly in the retrofitting of historic buildings. This can have major adverse effects on the building fabric and for its inhabitant’s health if the appropriate material interventions are not chosen. An inexpensive environmental chamber for testing such materials has been designed and built at the Dublin Institute of Technology, (DIT) Ireland, adopting comparable standards from EN ISO 8990 and ASTM C1363. This paper describes the design requirements for the construction of an affordable and mobile calibrated hot box (CHB) for the testing of historic materials. A characterisation panel has been used to carry out early calibration testing and the results of this are discussed. Improvements and tweaking of the first test are also discussed

A systematic review of randomized controlled trials on exercise parameters in the treatment of patellofemoral pain: what works?

Daniel Harvie, Timothy O'Leary, Saravana Kumar International Centre for Allied Health Evidence (iCAHE), City East Campus, University of South Australia, Adelaide, Australia Purpose: There is research evidence which supports the effectiveness of exercise in reducing pain and increasing function in patients with patellofemoral pain syndrome. However, what is unclear are the parameters underpinning this intervention. This has led to uncertainty when operationalizing exercises for patients with patellofemoral pain syndrome in clinical practice. The aim of this review was to evaluate the parameters of exercise programs reported in primary research, to provide clinicians with evidence-based recommendations for exercise prescription for patellofemoral pain. Methods: A systematic review of randomized controlled trials was undertaken. Only trials that identified exercise to be effective in treating patellofemoral pain were included. Appropriate databases and reference lists were searched using established keywords. Data relating to common exercise parameters such as the type of exercise, length, and frequency of intervention, intensity, repetitions, sets, and specific technique were extracted, along with details of co-interventions that may have been used. Results: A total of ten randomized controlled trials were included in this review and from these trials 14 interventions arms were evaluated. All 14 interventions focused on active exercises, all but two of which also included a passive stretching component. The current body of evidence demonstrates positive results with exercise interventions such as knee extension, squats, stationary cycling, static quadriceps, active straight leg raise, leg press, and step-up and down exercises for patients with patellofemoral pain syndrome. A progressive regime of daily exercises of two to four sets of ten or more repetitions over an intervention period of 6 weeks or more, combined with exercises to address flexibility of the lower limb musculature was commonly used. Conclusion: Currently, the primary research on this topic supports the use of closed kinetic chain, strengthening exercises for musculature of the lower limb, combined with flexibility options. The current evidence base supports a prescription of daily exercises of two–four sets of ten or more repetitions over a period of 6 weeks or more. Keywords: patellofemoral pain syndrome, PFPS, repetitions, lower limb, musculatur

The Effect of Dynamical Scattering on Single-plane Phase Retrieval in Electron Ptychography

Segmented and pixelated detectors on scanning transmission electron microscopes enable the complex specimen transmission function to be reconstructed. Imaging the transmission function is key to interpreting the electric and magnetic properties of the specimen, and as such four-dimensional scanning transmission electron microscopy (4D-STEM) imaging techniques are crucial for our understanding of functional materials. Many of the algorithms used in the reconstruction of the transmission function rely on the multiplicative approximation and the (weak) phase object approximation, which are not valid for many materials, particularly at high resolution. Herein, we study the breakdown of simple phase imaging in thicker samples. We demonstrate the behavior of integrated center of mass imaging, single-side band ptychography, and Wigner distribution deconvolution over a thickness series of simulated GaN 4D-STEM datasets. We further give guidance as to the optimal focal conditions for obtaining a more interpretable dataset using these algorithms

A comparison of biomarker records of northeast African vegetation from lacustrine and marine sediments (ca. 3.40 Ma)

Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Organic Geochemistry 38 (2007): 1607-1624, doi:10.1016/j.orggeochem.2007.06.008.Integrated terrestrial and marine records of northeast African vegetation are needed to provide long, high resolution records of environmental variability with established links to specific terrestrial environments. In this study, we compare records of terrestrial vegetation preserved in marine sediments in the Gulf of Aden (DSDP Site 231) and an outcrop of lacustrine sediments in the Turkana Basin, Kenya, part of the East African Rift System. We analyzed higher plant biomarkers in sediments from both deposits of known equivalent age, corresponding to a ca. 50 – 100 ka humid interval prior to the β-Tulu Bor eruption ca. 3.40 Ma, when the Lokochot Lake occupied part of the Turkana Basin. Molecular abundance distributions indicate that long chain n-alkanoic acids in marine sediments are the most reliable proxy for terrestrial vegetation (Carbon Preference Index, CPI, = 4.5), with more cautious interpretation needed for n-alkanes and lacustrine archives. Marine sediments record carbon isotopic variability in terrestrial biomarkers of 2 – 3‰, roughly equivalent to 20% variability in the C3/C4 vegetation contribution. The proportion of C4 vegetation apparently increased at times of low terrigenous dust input. Terrestrial sediments reveal much larger (2 – 10‰) shifts in n-alkanoic acid δ13C values. However, molecular abundance and isotopic composition suggest that microbial sources may also contribute fatty acids, contaminating the lacustrine sedimentary record of terrestrial vegetation.Funding was provided by the U.S. National Science Foundation HOMINID Grant 0218511