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排序方式: 共有1484条查询结果,搜索用时 15 毫秒
21.
Erik D. Marchant Jamie P. Kaluhiokalani Taysom E. Wallace Mohadeseh Ahmadi Abigail Dorff Jessica J. Linde Olivia K. Leach Robert D. Hyldahl Jayson R. Gifford Chad R. Hancock 《International journal of molecular sciences》2022,23(15)
AIM: Mild heat stress can improve mitochondrial respiratory capacity in skeletal muscle. However, long-term heat interventions are scarce, and the effects of heat therapy need to be understood in the context of the adaptations which follow the more complex combination of stimuli from exercise training. The purpose of this work was to compare the effects of 6 weeks of localized heat therapy on human skeletal muscle mitochondria to single-leg interval training. METHODS: Thirty-five subjects were assigned to receive sham therapy, short-wave diathermy heat therapy, or single-leg interval exercise training, localized to the quadriceps muscles of the right leg. All interventions took place 3 times per week. Muscle biopsies were performed at baseline, and after 3 and 6 weeks of intervention. Mitochondrial respiratory capacity was assessed on permeabilized muscle fibers via high-resolution respirometry. RESULTS: The primary finding of this work was that heat therapy and exercise training significantly improved mitochondrial respiratory capacity by 24.8 ± 6.2% and 27.9 ± 8.7%, respectively (p < 0.05). Fatty acid oxidation and citrate synthase activity were also increased following exercise training by 29.5 ± 6.8% and 19.0 ± 7.4%, respectively (p < 0.05). However, contrary to our hypothesis, heat therapy did not increase fatty acid oxidation or citrate synthase activity. CONCLUSION: Six weeks of muscle-localized heat therapy significantly improves mitochondrial respiratory capacity, comparable to exercise training. However, unlike exercise, heat does not improve fatty acid oxidation capacity. 相似文献
22.
Jessica Lin 《The Electricity Journal》2018,31(6):33-39
This case study highlights the success of the Ouachita Electric Cooperative’s Pay As You Save program in Camden, Ark., in bringing both electricity bill savings to customers and benefits to implementing utilities, especially in rural areas. It is not specifically a low-income energy assistance program, but does benefit customers with high energy burdens. Through its on-bill tariff design, PAYS overcomes many barriers, such as the split incentive challenge and the need for upfront outlays. 相似文献
23.
Julie K. Furmick Dr. Ichiro Kaneko Angela N. Walsh Joanna Yang Jaskaran S. Bhogal Geoffrey M. Gray Juan C. Baso Drew O. Browder Jessica L. S. Prentice Luis A. Montano Chanh C. Huynh Lisa M. Marcus Dorian G. Tsosie Jungeun S. Kwon Alexis Quezada Nicole M. Reyes Brittney Lemming Puneet Saini Dr. Arjan van der Vaart Dr. Thomas L. Groy Dr. Pamela A. Marshall Dr. Peter W. Jurutka Dr. Carl E. Wagner 《ChemMedChem》2012,7(9):1551-1566
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Christina M. Rudin-Brown Michael G. LennéJessica Edquist Jordan Navarro 《Accident; analysis and prevention》2012
Although collisions at level crossings are relatively uncommon occurrences, the potential severity of their consequences make them a top priority among safety authorities. Twenty-five fully-licensed drivers aged between 20 and 50 years participated in a driving simulator study that compared the efficacy, and drivers’ subjective perception, of two active level crossing traffic control devices: flashing lights with boom barriers and standard traffic lights. Because of its common usage in most states in Australia, a stop sign-controlled level crossing served as the passive referent. Although crossing violations were less likely at the level crossings controlled by active devices than at those controlled by stop signs, both kinds of active control were associated with a similar number of violations. Further, the majority (72%) of drivers reported preferring flashing lights to traffic lights. Collectively, results indicate that the installation of traffic lights at real-world level crossings would not be likely to offer safety benefits over and above those provided already by flashing lights with boom barriers. Furthermore, the high rate of violations at passively controlled crossings strongly supports the continued practice of upgrading level crossings with active traffic control devices. 相似文献
26.
Jessica Jones Schonna Manning Morela Montoya Karin Keller Martin Poenie 《Journal of the American Oil Chemists' Society》2012,89(8):1371-1381
Algae are a promising source of biofuel but claims about their lipid content can be ambiguous because extraction methods vary and lipid quantitation often does not distinguish between particular lipid classes. Here we compared methods for the extraction of algal lipids and showed that 2-ethoxyethanol (2-EE) provides superior lipid recovery (>150–200 %) compared to other common extraction solvents such as chloroform:methanol or hexane. Extractions of wet and dry algal biomass showed that 2-EE was more effective at extracting lipids from wet rather than dried algal pellets. To analyze lipid content we used normal-phase HPLC with parallel quantitation by an evaporative light scattering detector and a mass spectrometer. Analysis of crude lipid extracts showed that all major lipid classes could be identified and quantified and revealed a surprisingly large amount of saturated hydrocarbons (HC). This HC fraction was isolated from extracts of bioreactor-grown algae and further analyzed by HPLC/MS, NMR, and GC/MS. The results showed that the sample consisted of a mixture of saturated, straight- and branched-chain HC of different chain lengths. These algal HC could represent an alternative biofuel to triacylglycerols (TAG) that could feed directly into the current petroleum infrastructure. 相似文献
27.
Dan A. Buzatu Willie M. Cooper Christine Summage-West John B. Sutherland Anna J. Williams Deborah A. Bass Lisa L. Smith Robert S. Woodruff Jessica M. Christman Steven Reid Randal K. Tucker Christopher J. Haney Ashfaqe Ahmed Fatemeh Rafii Jon G. Wilkes 《Food microbiology》2013
A flow cytometric method (RAPID-B™) with detection sensitivity of one viable cell of Escherichia coli serotype O157:H7 in fresh spinach (Spinacia oleracea) was developed and evaluated. The major impediment to achieving this performance was mistaking autofluorescing spinach particles for tagged target cells. Following a 5 h non-selective enrichment, artificially inoculated samples were photobleached, using phloxine B as a photosensitizer. Samples were centrifuged at high speed to concentrate target cells, then gradient centrifuged to separate them from matrix debris. In external laboratory experiments, RAPID-B and the reference method both correctly detected E. coli O157:H7 at inoculations of ca. 15 cells. In a follow-up study, after 4 cell inoculations of positives and 6 h enrichment, RAPID-B correctly identified 92% of 25 samples. The RAPID-B method limit of detection (LOD) was one cell in 25 g. It proved superior to the reference method (which incorporated real time-PCR, selective enrichment, and culture plating elements) in accuracy and speed. 相似文献
28.
Linkenauger Sally A.; Witt Jessica K.; Stefanucci Jeanine K.; Bakdash Jonathan Z.; Proffitt Dennis R. 《Canadian Metallurgical Quarterly》2009,35(6):1649
Previous research has suggested that perceived distances are scaled by the action capabilities of the body. The present studies showed that when “reachability” is constrained due to a difficult grasp required to pick up an object, perceived distance to the object increases. Participants estimated the distances to tools with handle orientations that made them either easy or difficult to grasp with their dominant and nondominant hands. Right-handed participants perceived tools that were more difficult to grasp to be farther away than tools that were easier to grasp. However, perceived distance did not differ in left-handed participants. These studies suggest that, when reaching toward a target, the distance to that target is scaled in terms of how far one can effectively reach, given the type of reaching posture that is executed. Furthermore, this effect is modulated by handedness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The Density of States and the Transport Effective Mass in a Highly Oriented Semiconducting Polymer: Electronic Delocalization in 1D 下载免费PDF全文