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life cycle testing

Dimorvan Bordin, Edmara T P Bergamo, Estevam A Bonfante, Vinicius P Fardin, Paulo G Coelho
PURPOSE: To evaluate the influence of implant diameter in the reliability and failure mode of extra-short dental implants. MATERIALS AND METHODS: Sixty-three extra-short implants (5mm-length) were allocated into three groups according to platform diameter: Ø4.0-mm, Ø5.0-mm, and Ø6.0-mm (21 per group). Identical abutments were torqued to the implants and standardized crowns cemented. Three samples of each group were subjected to single-load to failure (SLF) to allow the design of the step-stress profiles, and the remaining 18 were subjected to step-stress accelerated life-testing (SSALT) in water...
September 21, 2017: Journal of the Mechanical Behavior of Biomedical Materials
Belen Zapata-Diomedi, Luke D Knibbs, Robert S Ware, Kristiann C Heesch, Marko Tainio, James Woodcock, J Lennert Veerman
INTRODUCTION: An alarmingly high proportion of the Australian adult population does not meet national physical activity guidelines (57%). This is concerning because physical inactivity is a risk factor for several chronic diseases. In recent years, an increasing emphasis has been placed on the potential for transport and urban planning to contribute to increased physical activity via greater uptake of active transport (walking, cycling and public transport). In this study, we aimed to estimate the potential health gains and savings in health care costs of an Australian city achieving its stated travel targets for the use of active transport...
2017: PloS One
Phoeve Macario, Mauro Pichorim, Paul F Doherty, Guilherme S Toledo-Lima, Tonny M Oliveira-Júnior, Thanyria P F Câmara, Shirley Macjane Melo, João Lucas S Silveira, Juliana C Araújo, Leonardo F França
Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-lined Tanager (Tachyphonus rufus) using capture-mark-recapture data from northeastern Brazil. We tested whether survival varied seasonally (breeding vs...
2017: PloS One
Megan L McKenna, Shannon McAtee, Patricia E Bryan, Rebecca Jeun, Tabitha Ward, Jacob Kraus, Maria E Bottazzi, Peter J Hotez, Catherine C Flowers, Rojelio Mejia
Hookworm infection affects 430 million people worldwide, causing iron deficiency, impaired cognitive development, and stunting in children. Because of the environmental conditions needed for the hookworm life-cycle, this parasite is endemic to resource-limited countries. Necator americanus was endemic in the southern United States before improvement of sewage disposal systems and eradication programs. With continued poverty, poor sanitation, and an environment suitable for the hookworm life-cycle in some regions of the southern United States, a current prevalence study using modern molecular diagnostics is warranted...
September 5, 2017: American Journal of Tropical Medicine and Hygiene
Melissa D Conrad, Daniel Mota, Alex Musiime, Maxwell Kilama, John Rek, Moses Kamya, Grant Dorsey, Philip J Rosenthal
Controlling malaria in high transmission areas, such as much of sub-Saharan Africa, will require concerted efforts to slow the spread of drug resistance and to impede malaria transmission. Understanding the fitness costs associated with the development of drug resistance, particularly within the context of transmission, can help guide policy decisions to accomplish these goals, as fitness constraints might lead to decreased transmission of drug-resistant strains. To determine if Plasmodium falciparum resistance-mediating polymorphisms impact on development at different parasite stages, we compared the genotypes of parasites infecting humans and mosquitoes from households in Uganda...
September 25, 2017: American Journal of Tropical Medicine and Hygiene
Marian Wilson, Regan Permito, Ashley English, Sandra Albritton, Carlana Coogle, Hans P A Van Dongen
Hospitals are around-the-clock operations and nurses are required to care for patients night and day. The nursing shortage and desire for a more balanced work-to-home life has popularized 12-h shifts for nurses. The present study investigated sleep/wake cycles and fatigue levels in 22 nurses working 12-h shifts, comparing day versus night shifts. Nurses (11day shift and 11 night shift) were recruited from a suburban acute-care medical center. Participants wore a wrist activity monitor and kept a diary to track their sleep/wake cycles for 2 weeks...
October 5, 2017: Accident; Analysis and Prevention
Peter T Green, Kyle E Harms
The emergent properties of the collection of species in a natural community, such as diversity and the distribution of relative abundances, are influenced by both niche-based and neutral (stochastic) processes. This pluralistic view of the natural world reconciles theory with empirical observations better than does either a strictly niche- or neutrality-based perspective. Even so, rules (or rules-of-thumb) that govern the relative contributions that niche-based and stochastic processes make as communities assemble remain only vaguely formulated and incompletely tested...
October 4, 2017: Ecology
Michael J Thorpy, George Hiller
BACKGROUND: The neurologic disorder narcolepsy results from dysregulation of the sleep-wake cycle and is primarily characterized by chronic, severely excessive daytime sleepiness and cataplexy, an emotionally induced muscle weakness. The prevalence of narcolepsy is approximately 0.05%, and onset generally occurs during the first 2 decades of life. Narcolepsy is believed to be an autoimmune disorder with destruction of hypocretin-producing neurons in the lateral hypothalamus. OBJECTIVES: To provide an enhanced understanding of narcolepsy and establish the need for early diagnosis and rapid initiation of effective treatment for patients with narcolepsy...
July 2017: American Health & Drug Benefits
Ola Stedje Hanserud, Francesco Cherubini, Anne Falk Øgaard, Daniel B Müller, Helge Brattebø
Increased nutrient cycling in the agri-food system is a way to achieve a healthier nutrient stewardship and more sustainable food production. In life cycle assessment (LCA) studies, use of recycled fertilizer products is often credited by the substitution method, which subtracts the environmental burdens associated with avoided production of mineral fertilizer from the system under study. The environmental benefits from avoided fertilizer production can make an important contribution to the results, but different calculation principles and often implicit assumptions are used to estimate the amount of avoided mineral fertilizer...
September 30, 2017: Science of the Total Environment
Othman Al-Khudairi, Homayoun Hadavinia, Christian Little, Gavin Gillmore, Peter Greaves, Kirsten Dyer
In this paper, the sensitivity of the structural integrity of wind turbine blades to debonding of the shear web from the spar cap was investigated. In this regard, modal analysis, static and fatigue testing were performed on a 45.7 m blade for three states of the blade: (i) as received blade (ii) when a crack of 200 mm was introduced between the web and the spar cap and (iii) when the crack was extended to 1000 mm. Calibration pull-tests for all three states of the blade were performed to obtain the strain-bending moment relationship of the blade according to the estimated target bending moment (BM) which the blade is expected to experience in its service life...
October 3, 2017: Materials
Gregory R Hopkins, Bradley E Dougherty, Angela M Brown
SIGNIFICANCE: This report describes the first clinical use of the Ohio Contrast Cards, a new test that measures the maximum spatial contrast sensitivity of low-vision patients who cannot recognize and identify optotypes and for whom the spatial frequency of maximum contrast sensitivity is unknown. PURPOSE: To compare measurements of the Ohio Contrast Cards to measurements of three other vision tests and a vision-related quality-of-life questionnaire obtained on partially sighted students at Ohio State School for the Blind...
October 2017: Optometry and Vision Science: Official Publication of the American Academy of Optometry
Ivan Valkov, Radina Ivanova, Assen Alexiev, Krasimir Antonov, Lyudmila Mateva
INTRODUCTION: Hepatitis C Virus (HCV) relies on host lipids for its life cycle contributing to lipid abnormalities and hepatic steatosis. Disease progression is influenced by viral factors interacting with host immune and metabolic pathways. The significance of serum lipids for Chronic Hepatitis C (CHC) assessment is not clearly established yet. AIM: Our aim was to investigate serum lipids' association with stage of liver fibrosis, steatosis and genotypes in patients with CHC...
August 2017: Journal of Clinical and Diagnostic Research: JCDR
Donelly A van Schalkwyk, Robert W Moon, Benjamin Blasco, Colin J Sutherland
Background: The simian malaria parasite Plasmodium knowlesi is now a well-recognized pathogen of humans in South-East Asia. Clinical infections appear adequately treated with existing drug regimens, but the evidence base for this practice remains weak. The availability of P. knowlesi cultures adapted to continuous propagation in human erythrocytes enables specific studies of in vitro susceptibility of the species to antimalarial agents, and could provide a surrogate system for testing investigational compounds against Plasmodium vivax and other non- Plasmodium falciparum infections that cannot currently be propagated in vitro ...
August 30, 2017: Journal of Antimicrobial Chemotherapy
Aamir Ilyas, Tone M Muthanna
The aim of this paper was to conduct pilot-scale column tests on an alternative treatment filter designed for the treatment of highway stormwater in cold climates. The study evaluated adsorption performance of the filter with regard to the four most commonly found metals (Cu, Ni, Pb, and Zn) in highway stormwater. An alternative method was used to estimate the operational life of the filter from the adsorption test data without a breakthrough under high hydraulic loads. The potential environmental impact of the filter was assessed by comparing desorption test data with four different environmental quality standards...
September 29, 2017: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Rene Molina, Michael S Okun, Jonathan B Shute, Enrico Opri, P Justin Rossi, Daniel Martinez-Ramirez, Kelly D Foote, Aysegul Gunduz
Deep brain stimulation (DBS) has emerged as a promising intervention for the treatment of select movement and neuropsychiatric disorders. Current DBS therapies deliver electrical stimulation continuously and are not designed to adapt to a patient's symptoms. Continuous DBS can lead to rapid battery depletion, which necessitates frequent surgery for battery replacement. Next-generation neurostimulation devices can monitor neural signals from implanted DBS leads, where stimulation can be delivered responsively, moving the field of neuromodulation away from continuous paradigms...
September 29, 2017: Journal of Neurosurgery
David W Cobb, Anat Florentin, Manuel A Fierro, Michelle Krakowiak, Julie M Moore, Vasant Muralidharan
Export of parasite proteins into the host erythrocyte is essential for survival of Plasmodium falciparum during its asexual life cycle. While several studies described key factors within the parasite that are involved in protein export, the mechanisms employed to traffic exported proteins within the host cell are currently unknown. Members of the Hsp70 family of chaperones, together with their Hsp40 cochaperones, facilitate protein trafficking in other organisms, and are thus likely used by P. falciparum in the trafficking of its exported proteins...
September 2017: MSphere
Kaikai Li, Baohua Li, Junxiong Wu, Feiyu Kang, Jang-Kyo Kim, Tong-Yi Zhang
Ideal lithium-ion batteries (LIBs) should possess a high power density, be charged extremely fast (e.g., 100C), and have a long service life. To achieve them all, all battery components, including anodes, cathodes, and electrolytes should have excellent structural and functional characteristics. The present work reports ultrafast-charging and long-life LIB anodes made from TiO2-B/anatase dual-phase nanowires. The dual-phase nanowires are fabricated with anatase TiO2 nanoparticles through a facile and cost-effective hydrothermal process, which can be easily scaled up for mass production...
October 6, 2017: ACS Applied Materials & Interfaces
Priya Gupta, Sonali Mehrotra, Anil Sharma, Monika Chugh, Rajan Pandey, Abhinav Kaushik, Sachin Khurana, Neha Srivastava, Tarushikha Srivastava, Arunaditya Deshmukh, Ashutosh Panda, Priyanka Aggarwal, Neel Sarovar Bhavesh, Raj K Bhatnagar, Asif Mohmmed, Dinesh Gupta, Pawan Malhotra
Hemoglobin degradation/hemozoin formation, essential steps in the Plasmodium life cycle, are targets of existing antimalarials. The pathway still offers vast possibilities to be explored for new antimalarial discoveries. Here, we characterize heme detoxification protein, PfHDP, a major protein involved in hemozoin formation, as a novel drug target. Using in silico and biochemical approaches, we identified two heme binding sites and a hemoglobin binding site in PfHDP. Treatment of Plasmodium falciparum 3D7 parasites with peptide corresponding to the hemoglobin binding domain in PfHDP resulted in food vacuole abnormalities similar to that seen with a cysteine protease inhibitor, E-64 (I-1)...
October 11, 2017: Journal of Medicinal Chemistry
Mirna Kaafarani, Christian Schroer, Tim Takken
BACKGROUND: It is now common practice to use hemodynamic responses to exercise as markers of diagnosis for cardiac diseases in children, systolic blood pressure especially. However, the reference values for SBP in children at peak exertion level are outdated, and, without a current definition of normal, clinicians cannot determine the physiologically impaired. OBJECTIVE: This study aimed to establish current reference values for peak systolic blood pressure (SBP), rate pressure product (RPP), and circulatory power (CircP)...
September 26, 2017: Expert Review of Cardiovascular Therapy
Silvia I Quinzio, John O Reiss
The aquatic-to-terrestrial shift in the life cycle of most anurans suggests that the differences between the larval and adult morphology of the nose are required for sensory function in two media with different physical characteristics. However, a better controlled test of specialization to medium is to compare adult stages of terrestrial frogs with those that remain fully aquatic as adults. The Ceratophryidae is a monophyletic group of neotropical frogs whose diversification from a common terrestrial ancestor gave rise to both terrestrial (Ceratophrys, Chacophrys) and aquatic (Lepidobatrachus) adults...
September 26, 2017: Journal of Morphology
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