LENS® and SFF: Enabling Technologies for Optimized Structures

Optimized, lightweight, high-strength structures are needed in many applications from aerospace to automotive. In pursuit of such structures, there have been proposed analytical solutions and some specialized FEA solutions for specific structures such as automobile frames. However, generalized 3D optimization methods have been unavailable for use by most designers. Moreover, in the cases where optimized structural solutions are available, they are often hollow, curving, thin wall structures that cannot be fabricated by conventional manufacturing methods. Researchers at Sandia National Laboratories and the University of Rhode Island teamed to solve these problems. The team has been pursuing two methods of optimizing models for generalized loading conditions, and also has been investigating the methods needed to fabricate these structures using Laser Engineered Net Shaping™ (LENS®) and other rapid prototyping methods. These solid freeform fabrication (SFF) methods offer the unique ability to make hollow, high aspect ratio features out of many materials. The manufacturing development required for LENS to make these complex structures has included the addition of rotational axes to Sandia’s LENS machine bringing the total to 5 controlled axes. The additional axes have required new efforts in process planning. Several of the unique structures that are only now possible through the use of SFF technology are shown as part of the discussion of this exciting new application for SFF.Mechanical Engineerin

A systematic review of interventions in primary care to improve health literacy for chronic disease behavioral risk factors

Background: To evaluate the effectiveness of interventions used in primary care to improve health literacy for change in smoking, nutrition, alcohol, physical activity and weight (SNAPW). Methods: A systematic review of intervention studies that included outcomes for health literacy and SNAPW behavioral risk behaviors implemented in primary care settings. We searched the Cochrane Library, Johanna Briggs Institute, Medline, Embase, CINAHL, Psychinfo, Web of Science, Scopus, APAIS, Australasian Medical Index, Google Scholar, Community of Science and four targeted journals (Patient Education and Counseling, Health Education and Behaviour, American Journal of Preventive Medicine and Preventive Medicine). Study inclusion criteria: Adults over 18 years; undertaken in a primary care setting within an Organisation for Economic Co-operation and Development (OECD) country; interventions with at least one measure of health literacy and promoting positive change in smoking, nutrition, alcohol, physical activity and/or weight; measure at least one outcome associated with health literacy and report a SNAPW outcome; and experimental and quasi-experimental studies, cohort, observational and controlled and non-controlled before and after studies. Papers were assessed and screened by two researchers (JT, AW) and uncertain or excluded studies were reviewed by a third researcher (MH). Data were extracted from the included studies by two researchers (JT, AW). Effectiveness studies were quality assessed. A typology of interventions was thematically derived from the studies by grouping the SNAPW interventions into six broad categories: individual motivational interviewing and counseling; group education; multiple interventions (combination of interventions); written materials; telephone coaching or counseling; and computer or web based interventions. Interventions were classified by intensity of contact with the subjects (High ≥ 8 points of contact/hours; Moderate \u3e3 and \u3c8; Low ≤ 3 points of contact hours) and setting (primary health, community or other). Studies were analyzed by intervention category and whether significant positive changes in SNAPW and health literacy outcomes were reported. Results: 52 studies were included. Many different intervention types and settings were associated with change in health literacy (73% of all studies) and change in SNAPW (75% of studies). More low intensity interventions reported significant positive outcomes for SNAPW (43% of studies) compared with high intensity interventions (33% of studies). More interventions in primary health care than the community were effective in supporting smoking cessation whereas the reverse was true for diet and physical activity interventions. Conclusion: Group and individual interventions of varying intensity in primary health care and community settings are useful in supporting sustained change in health literacy for change in behavioral risk factors. Certain aspects of risk behavior may be better handled in clinical settings while others more effectively in the community. Our findings have implications for the design of programs

Diferentiation of SH‑SY5Y neuroblastoma cells using retinoic acid and BDNF: a model for neuronal and synaptic diferentiation in neurodegeneration

There has been much interest in the use of cell culture models of neurones, to avoid the animal welfare and cost issues of using primary and human-induced pluripotent stem cell (hiPSC)-derived neurones respectively. The human neuroblastoma cell line, SH-SY5Y, is extensively used in laboratories as they can be readily expanded, are of low cost and can be differentiated into neuronal-like cells. However, much debate remains as to their phenotype once differentiated, and their ability to recapitulate the physiology of bona fide neurones. Here, we characterise a differentiation protocol using retinoic acid and BDNF, which results in extensive neurite outgrowth/branching within 10 days, and expression of key neuronal and synaptic markers. We propose that these differentiated SH-SY5Y cells may be a useful substitute for primary or hiPSC-derived neurones for cell biology studies, in order to reduce costs and animal usage. We further propose that this characterised differentiation timecourse could be used as an in vitro model for neuronal differentiation, for proof-of principle studies on neurogenesis, e.g. relating to neurodegenerative diseases. Finally, we demonstrate profound changes in Tau phosphorylation during differentiation of these cells, suggesting that they should not be used for neurodegeneration studies in their undifferentiated state

Absolute probability estimates of lethal vessel strikes to North Atlantic right whales in Roseway Basin, Scotian Shelf

Author Posting. © Ecological Society of America, 2012. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecological Applications 22 (2012): 2021–2033, doi:10.1890/11-1841.1.Vessel strikes are the primary source of known mortality for the endangered North Atlantic right whale (Eubalaena glacialis). Multi-institutional efforts to reduce mortality associated with vessel strikes include vessel-routing amendments such as the International Maritime Organization voluntary “area to be avoided” (ATBA) in the Roseway Basin right whale feeding habitat on the southwestern Scotian Shelf. Though relative probabilities of lethal vessel strikes have been estimated and published, absolute probabilities remain unknown. We used a modeling approach to determine the regional effect of the ATBA, by estimating reductions in the expected number of lethal vessel strikes. This analysis differs from others in that it explicitly includes a spatiotemporal analysis of real-time transits of vessels through a population of simulated, swimming right whales. Combining automatic identification system (AIS) vessel navigation data and an observationally based whale movement model allowed us to determine the spatial and temporal intersection of vessels and whales, from which various probability estimates of lethal vessel strikes are derived. We estimate one lethal vessel strike every 0.775–2.07 years prior to ATBA implementation, consistent with and more constrained than previous estimates of every 2–16 years. Following implementation, a lethal vessel strike is expected every 41 years. When whale abundance is held constant across years, we estimate that voluntary vessel compliance with the ATBA results in an 82% reduction in the per capita rate of lethal strikes; very similar to a previously published estimate of 82% reduction in the relative risk of a lethal vessel strike. The models we developed can inform decision-making and policy design, based on their ability to provide absolute, population-corrected, time-varying estimates of lethal vessel strikes, and they are easily transported to other regions and situations.This research was supported by the Environment Canada Habitat Stewardship Programme, the Canadian Whale Institute, and R. K. Smedbol (St. Andrews Biological Station)

Fecundity variation in Icelandic summer-spawning herring and implications for reproductive potential

An exploration of fish fecundity aimed at estimating the reproductive potential of a stock requires comprehensive and quantitative examinations of the influencing factors. Here, Icelandic summer-spawning herring (Clupea harengus) are used to quantify potential fecundity (F P , number of eggs) and relative fecundity [RF P ¼ F P (body weight ÿ ovary weight) ÿ1 ] as functions of length (L) and weight (W ) in mature prespawning herring. Using a coupled examination of atresia (oocyte degeneration in the ovary) and the maturation stage of oocytes as characterized by size, we show that atresia has no meaningful effect on fecundity estimates if determined near the spawning time. Among prespawning herring, F P is a strong function of L or W (r 2 ¼ 0.84 in either case). Fulton's condition factor K

Passive tracer reconstruction as a least-squares problem with a semi-Lagrangian constraint: An application to fish eggs and larvae

A variational, data assimilation, algorithm was developed for reconstruction of a two-dimensional, nonstationary, passive tracer field in the ocean with open boundaries and a known velocity field. The observations, spatial smoothing terms and passive tracer conservation equation were included as weak constraints. The algorithm was tested with simulated, nonstationary, pseudo-oceanographic data integrated for a 7-day period. Simulations were run to determine the robustness of the algorithm and the effect of theoretical, simulated \u27sampling events,\u27 mimicking the standard oceanographic survey. We explored the sensitivity of the reconstructed tracer fields to the distribution of the pseudo-oceanographic sampling strategy, essentially an antenna problem, and to errors in the velocity field and the observations. The algorithm was applied to observations of silver hake ( Merluccius bilinearis) eggs and larvae obtained in August 1998 on the Scotian Shelf. Finally, the evolution of fish eggs and larvae concentration was found. The corresponding mortality rate of fish eggs and larvae was determined to be 0.28 day-1, with errors of 0.03 day-1. The approach, which is quite general and could be applied to many different problems requiring minimization subject to constraints, allows for error analysis of the results