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2011

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Articles 421 - 450 of 5492

Full-Text Articles in Life Sciences

Planning Combinatorial Disulfide Cross-Links For Protein Fold Determination, Fei Xiong, Alan M Friedman, Chris Bailey-Kellogg Nov 2011

Planning Combinatorial Disulfide Cross-Links For Protein Fold Determination, Fei Xiong, Alan M Friedman, Chris Bailey-Kellogg

Dartmouth Scholarship

Fold recognition techniques take advantage of the limited number of overall structural organizations, and have become increasingly effective at identifying the fold of a given target sequence. However, in the absence of sufficient sequence identity, it remains difficult for fold recognition methods to always select the correct model. While a native-like model is often among a pool of highly ranked models, it is not necessarily the highest-ranked one, and the model rankings depend sensitively on the scoring function used. Structure elucidation methods can then be employed to decide among the models based on relatively rapid biochemical/biophysical experiments.


Phylogenomics Of Reichenowia Parasitica, An Alphaproteobacterial Endosymbiont Of The Freshwater Leech Placobdella Parasitica, Sebastian Kvist, Apurva Narechania, Alejandro Oceguera-Figueroa, Bella Fuks, Mark E. Siddall Nov 2011

Phylogenomics Of Reichenowia Parasitica, An Alphaproteobacterial Endosymbiont Of The Freshwater Leech Placobdella Parasitica, Sebastian Kvist, Apurva Narechania, Alejandro Oceguera-Figueroa, Bella Fuks, Mark E. Siddall

Publications and Research

Although several commensal alphaproteobacteria form close relationships with plant hosts where they aid in (e.g.,) nitrogen fixation and nodulation, only a few inhabit animal hosts. Among these, Reichenowia picta, R. ornata and R. parasitica, are currently the only known mutualistic, alphaproteobacterial endosymbionts to inhabit leeches. These bacteria are harbored in the epithelial cells of the mycetomal structures of their freshwater leech hosts, Placobdella spp., and these structures have no other obvious function than housing bacterial symbionts. However, the function of the bacterial symbionts has remained unclear. Here, we focused both on exploring the genomic makeup of R. parasitica and on …


An Appreciation Of Ralph Marvin Steinman (1943-2011), Carol L. Moberg Nov 2011

An Appreciation Of Ralph Marvin Steinman (1943-2011), Carol L. Moberg

Steinman and the Nobel Prize

Posted with Permission.The Rockefeller University Press J. Exp. Med. Vol. 208 No. 12 2337-2342 www.jem.org/cgi/doi/10.1084/jem.20112294


Insulin Receptor-Mediated Signaling Via Phospholipase C-Γ Regulates Growth And Differentiation In Drosophila, Juan M. Murillo-Maldonado, Fouad Bou Zeineddine, Rachel Stock, Justin Thackeray, Juan R. Riesgo-Escovar Nov 2011

Insulin Receptor-Mediated Signaling Via Phospholipase C-Γ Regulates Growth And Differentiation In Drosophila, Juan M. Murillo-Maldonado, Fouad Bou Zeineddine, Rachel Stock, Justin Thackeray, Juan R. Riesgo-Escovar

Biology

Coordination between growth and patterning/differentiation is critical if appropriate final organ structure and size is to be achieved. Understanding how these two processes are regulated is therefore a fundamental and as yet incompletely answered question. Here we show through genetic analysis that the phospholipase C-γ (PLC-γ) encoded by small wing (sl) acts as such a link between growth and patterning/differentiation by modulating some MAPK outputs once activated by the insulin pathway; particularly, sl promotes growth and suppresses ectopic differentiation in the developing eye and wing, allowing cells to attain a normal size and differentiate properly. sl mutants have previously been …


Additive Functions In Boolean Models Of Gene Regulatory Network Modules, Christian Darabos, Ferdinando Ferdinando Di Cunto, Marco Tomassini, Jason H. Moore Nov 2011

Additive Functions In Boolean Models Of Gene Regulatory Network Modules, Christian Darabos, Ferdinando Ferdinando Di Cunto, Marco Tomassini, Jason H. Moore

Dartmouth Scholarship

Gene-on-gene regulations are key components of every living organism. Dynamical abstract models of genetic regulatory networks help explain the genome’s evolvability and robustness. These properties can be attributed to the structural topology of the graph formed by genes, as vertices, and regulatory interactions, as edges. Moreover, the actual gene interaction of each gene is believed to play a key role in the stability of the structure. With advances in biology, some effort was deployed to develop update functions in Boolean models that include recent knowledge. We combine real-life gene interaction networks with novel update functions in a Boolean model. We …


A Comparative Study On The Polyphenolic Content, Antibacterial Activity And Antioxidant Capacity Of Different Solvent Extracts Of Brassica Oleracea Vegetables, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta Nov 2011

A Comparative Study On The Polyphenolic Content, Antibacterial Activity And Antioxidant Capacity Of Different Solvent Extracts Of Brassica Oleracea Vegetables, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Brassica vegetables are rich in polyphenols, flavonoids and glucosinolates. Investigation was undertaken to optimise the best solvents among 60% ethanol, acetone and methanol for the extraction of polyphenols from Brassica vegetables. Furthermore, different properties such as antibacterial activity and antioxidant capacity were also investigated. Results showed that a 60% methanolic extract showed the highest total phenolic content which was 23.6, 20.4 and 18.7 mg gallic acid equivalents (GAE) g−1 extract for broccoli, Brussels sprouts and white cabbage, respectively. The hydroxybenzoic acid content of various solvent extracts ranged from 5.86 to 8.91 GAE g−1 extract for broccoli, 2.70 to 5.44 GAE …


Physical And Mechanical Properties Of Jute Mat Reinforced Epoxy Composites, Sadaf S.M, Siddik M, Ahsan Q Nov 2011

Physical And Mechanical Properties Of Jute Mat Reinforced Epoxy Composites, Sadaf S.M, Siddik M, Ahsan Q

ASEAN Journal on Science and Technology for Development

Cellulose jute fibre offers a number of benefits as reinforcement for synthetic polymers since it has a high specific strength and stiffness, low hardness, relatively low density and biodegradability. To reduce moisture uptake and hence to improve the mechanical properties of the composites, bleached jute mats were incorporated as reinforcing elements in the epoxy matrix. Composites at varying volume fractions and different orientations of jute mat were fabricated by hot compression machine under specific pressures and temperatures. Tensile, flexure, impact and water absorption tests of composites were conducted. Jute mat oriented at (0 ± 45–90)° composites showed reduced strength compared …


Nutrient Composition Of Artocarpus Champeden And Its Hybrid (Nanchem) In Negara Brunei Darussalam, Lim L.B.L, Chieng H.I, Wimmer F.L Nov 2011

Nutrient Composition Of Artocarpus Champeden And Its Hybrid (Nanchem) In Negara Brunei Darussalam, Lim L.B.L, Chieng H.I, Wimmer F.L

ASEAN Journal on Science and Technology for Development

The flesh and seeds of ripened and unripened Artocarpus champeden and its ripened hybrid (Nanchem) were analyzed for their moisture, ash, crude fibre, crude protein, crude fat, total carbohydrate, energy and mineral content. Generally, unripened A. champeden which is always treated and cooked as a vegetable contains higher amounts of moisture, ash, crude fibre and crude protein for its flesh than ripened A. champeden and Nanchem. Ripened A. champeden and Nanchemhave higher total carbohydrates and energy content than the unripe fruit. Similarly, the unripened A. champeden seed has more nutritional components in terms of moisture, ash, crude fibre, crude protein, …


Field And Laboratory-Based Approach For The Determination Of Friction Angle Of Geological Discontinuities Of Malaysian Granites, Ghani R. A, Goh T. L, Hariri A. M, Baizura Y. N Nov 2011

Field And Laboratory-Based Approach For The Determination Of Friction Angle Of Geological Discontinuities Of Malaysian Granites, Ghani R. A, Goh T. L, Hariri A. M, Baizura Y. N

ASEAN Journal on Science and Technology for Development

The basic friction angle, Φb for artificially sawn discontinuity planes for fresh granite, as determined by tilt testing, has an average value of 30º. For the natural rough discontinuity surfaces, a wide range of values have been determined for the peak friction angle, Φpeak ranging from 47º to a maximum value of 80º, depending on the joint roughness coefficient (JRC). The average values of the friction angles for the different degrees of roughness were as follows: JRC 2–4 = 58°; JRC 6–8 = 60°; JRC 8–10 = 47°; JRC 12–14 = 60°; JRC 14–16 = 71° ; JRC 18–20 = …


Usage Of Uasb Reactor To Assess Feasibility Of Treatment Of Paper Mill Effluent, Arshad A, Hashim N.H, Ghazala N Nov 2011

Usage Of Uasb Reactor To Assess Feasibility Of Treatment Of Paper Mill Effluent, Arshad A, Hashim N.H, Ghazala N

ASEAN Journal on Science and Technology for Development

Upflow anaerobic sludge blanket (UASB) reactors R-I and R-II, each with an effective volume of 6.0 l were used to study the treatability of actual effluent obtained from paper mills at a mesophilic temperature and neutral pH. Methanol, as a source of an easily biodegradable substance along with activated carbon of effective size 1.5 mm–2.5 mm were added to the reactor R-I to a total depth of 12 cm to evaluate its efficiency. The pH of both the reactors were kept constant at neutral by adding an external buffer solution of 0.03 M NaHCO3 with the feed solution. It was …


Recycling Mimeograph-Printed Newsprint Paper, Mari E. L, Torres A.S, Austria C.O Nov 2011

Recycling Mimeograph-Printed Newsprint Paper, Mari E. L, Torres A.S, Austria C.O

ASEAN Journal on Science and Technology for Development

Virgin newsprint paper from thermo-mechanical pulp was subjected to a laboratory recycling scheme, which involved mimeograph-printing, re-pulping, de-inking, washing, refining, and handsheetforming, without adding other fibre in between cycles. Fibre dimension, pulp freeness and paper properties were determined after each cycle until the fifth, at which about 20% of the original material remained. The remaining fibre was then mixed with virgin pulp, the original newsprint and unsorted mixed office waste to determine the proportion necessary for acceptable properties. The results indicated remarkable modification in distribution of fibre properties, a decreasing amount of long fibre with corresponding increase of short fibre …


Assessment Of The Treatment Of Textile Mill Effluent Using Uasb Reactor, Arshad A, Hashim N.H, Kashif A.K, Bashir A Nov 2011

Assessment Of The Treatment Of Textile Mill Effluent Using Uasb Reactor, Arshad A, Hashim N.H, Kashif A.K, Bashir A

ASEAN Journal on Science and Technology for Development

This study was designed to evaluate the feasibility of the treatment of actual textile mill effluent using a upflow anaerobic sludge blanket (UASB) reactor. The main objective of this study was to generate design aids; in terms of organic loading rate (OLR), hydraulic retention time (HRT) versus chemical oxygen demand (COD) and colour removal in the textile effluent using a UASB reactor at neutral pH and constant mesophilic temperature. The COD, colour and total suspended solids concentration of the textile wastes used in the study were analyzed as 5440 mg/l, 3280 mg/l, 2320 units and 955 mg/l, respectively. The UASB …


The Invasive Cactus Moth, Cactoblastis Cactorum: Host Plant Testing, Species Interactions, And Effects On Local Opuntia Populations, Heather Jezorek Nov 2011

The Invasive Cactus Moth, Cactoblastis Cactorum: Host Plant Testing, Species Interactions, And Effects On Local Opuntia Populations, Heather Jezorek

USF Tampa Graduate Theses and Dissertations

The invasive cactus moth, Cactoblastis cactorum, poses a threat to opunitoid cacti species of North America. The following work contains four separate studies investigating C. cactorum host plant preference and performance, predation and parastitism of C. cactorum, effects of C. cactorum on local Opuntia populations, and associational effects of host and non-host plants on C. cactorum and native Opuntia-feeding herbivores. We found that, among southwestern and Mexican opuntioid taxa, moths preferred O. engelmannii var. linguiformis and var. engelmannii for oviposition, while Consolea rubescens and O. streptacantha were superior larval hosts. Oviposition was best predicted by number of cladodes and degree …


Shifting Species Interactions In Terrestrial Dryland Ecosystems Under Altered Water Availability And Climate Change, Kevin E. Mccluney, Jayne Belnap, Scott L. Collins, Angélica L. González, Elizabeth M. Hagen, J. Nathaniel Holland, Burt P. Kotler, Fernando T. Maestre, Stanley D. Smith, Blair O. Wolf Nov 2011

Shifting Species Interactions In Terrestrial Dryland Ecosystems Under Altered Water Availability And Climate Change, Kevin E. Mccluney, Jayne Belnap, Scott L. Collins, Angélica L. González, Elizabeth M. Hagen, J. Nathaniel Holland, Burt P. Kotler, Fernando T. Maestre, Stanley D. Smith, Blair O. Wolf

Biological Sciences Faculty Publications

No abstract provided.


Effects Of Supplementing Propionibacteria In Lactation Dairy Diets On Ruminal Fermentation In Continuous Cultures, Karmella Ann Dolecheck Nov 2011

Effects Of Supplementing Propionibacteria In Lactation Dairy Diets On Ruminal Fermentation In Continuous Cultures, Karmella Ann Dolecheck

Undergraduate Honors Capstone Projects

The aim of the present study was to assess characteristics of in vitro ruminal fermentation when mixed cultures were offered lactation dairy diets supplemented with the direct-fed microorganism, Propionibacterium P63 in continuous cultures. The design of the experiment was a 2 × 2 factorial with 4 replications. Diets based on corn silage and alfalfa hay as the forage sources were formulated; high forage (HF) or low forage (LF) diet with a forage-to-concentrate ratio of 60:40 or 40:60 (DM basis), respectively, was combined without or with P63 to form 4 treatments: HF without P63, HF with P63, LF without P63, and …


Smokejumper Obituary: Mullin, James "Jim" (Redding 1968), National Smokejumper Association Nov 2011

Smokejumper Obituary: Mullin, James "Jim" (Redding 1968), National Smokejumper Association

Smokejumper Obituaries

No abstract provided.


Shrubs As Sentinels Of Ordnance Contamination: Using Plant Physiology And Remote Sensing To Detect Tnt In Soils, Kathryn Rubis Nov 2011

Shrubs As Sentinels Of Ordnance Contamination: Using Plant Physiology And Remote Sensing To Detect Tnt In Soils, Kathryn Rubis

Theses and Dissertations

Methods for rapid, safe and effective detection of unmapped buried ordnance are vital to the protection of humans and environmental quality throughout the world. This study aimed to investigate the use of phytosensing and to understand the physiological response of woody plants to 2,4,6-trinitrotoluene (TNT) contamination. Baccharis halimifolia were potted in soils containing various concentrations of TNT and physiological responses were observed over a 9-week experimental period. Measurements included the collection of remotely sensed data, such as hyperspectral reflectance and chlorophyll fluorescence, and traditional plant-level physiological data. In accordance with the hypothesis, low levels of TNT improved physiological response in …


The Short-Term Effect Of Whole Body Vibration Training On Physical Capabilities On Active Young Recreational Athletes, Esteban Martinez Ballester, Ivan Chulvi Dr Nov 2011

The Short-Term Effect Of Whole Body Vibration Training On Physical Capabilities On Active Young Recreational Athletes, Esteban Martinez Ballester, Ivan Chulvi Dr

International Journal of Exercise Science: Conference Proceedings

In recent years, whole body vibration (WBV) has been the subject of a great amount of research towards improving physical capabilities as a postactivation potentiation because the muscle spindle’s sensitivity can be increased (Rittweger, 2010). Typically, WBV is realized by the subject above the platform in squat position while the platform oscillates at differences intensities and amplitudes. Previous reports have shown that WBV produces preconditioning effects that lead an increase of power and flexibility (Jacobs & Burns, 2009), but controversial data exists that have shown no positive effect if an optimal dosage is not used in a controlled manner (Wilcock …


On Centruroides Margaritatus (Gervais, 1841) And Closely Related Species (Scorpiones: Buthidae), Luis F. De Armas, Rolando Teruel, František Kovařík Nov 2011

On Centruroides Margaritatus (Gervais, 1841) And Closely Related Species (Scorpiones: Buthidae), Luis F. De Armas, Rolando Teruel, František Kovařík

Euscorpius

Centruroides edwardsii (Gervais, 1843) comb. nov. is restored as a valid species, and a male neotype from Riohacha, La Guajira Department, Colombia is herein designated; this species ranges from Mexico through Colombia, but there are no reliable records from Guatemala, Belize, and Panama; introduced populations also occur in Cuba (West Indies) and Senegal (Africa). We regard the following species as its junior synonyms: Scorpio (Atreus) degeerii Gervais, 1844, Centrurus gambiensis Karsch, 1879, Centruroides margaritatus septentrionalis Hoffmann, 1932, and Rhopalurus danieli Prado et Rios-Patiño, 1940. We also consider Centruroides margaritatus morenoi Mello-Leitão, 1945 as a junior synonym of …


A Checklist Of The Scorpions (Arachnida: Scorpiones) Of Panama, With Two New Records, Rolando Teruel, Michiel A.C. Cozijn Nov 2011

A Checklist Of The Scorpions (Arachnida: Scorpiones) Of Panama, With Two New Records, Rolando Teruel, Michiel A.C. Cozijn

Euscorpius

In the present note, we compile a checklist of all scorpion species recorded from Panama. A total of three families, five genera and 14 species are confirmed to occur in the country, and previous records of two other families, four genera, and nine species are discarded as misidentifications, mislabelings, or accidental introductions. Two Buthidae species are herein recorded for the first time from Panama: Tityus tayrona Lourenço, 1991 (so far known only from northern Colombia) and one apparently undescribed species of Ananteris Thorell, 1891.


An Examination Of Diet, Acculturation And Risk Factors For Heart Disease Among Jamaican Immigrants, Carol Renee Oladele Nov 2011

An Examination Of Diet, Acculturation And Risk Factors For Heart Disease Among Jamaican Immigrants, Carol Renee Oladele

USF Tampa Graduate Theses and Dissertations

Background: The South Florida region is home to over 85,000 Jamaican immigrants. Yet, little is known about the dietary intakes and predictors of risk of disease within this immigrant group. An assessment of dietary intakes and the development of dietary intake methodologies specific to the Jamaican population was important as it permitted accurate estimation of the nutrient intakes of this immigrant population whose dietary habits are not well documented. In addition, nothing is known about the prevalence of risk factors for heart disease or factors influencing risk factors among this immigrant group. The purpose of this study was to assess …


Discriminating Between Copers And Those With Chronic Ankle Instability With Clinical Outcomes, Erik A. Wikstrom, Jessica Plante Nov 2011

Discriminating Between Copers And Those With Chronic Ankle Instability With Clinical Outcomes, Erik A. Wikstrom, Jessica Plante

International Journal of Exercise Science: Conference Proceedings

Introduction: Chronic ankle instability (CAI) is a common consequence of lateral ankle sprains and a leading cause of post-traumatic ankle osteoarthritis. Despite a history of a lateral ankle sprain, there are some individuals (copers) who appear to have a mechanism that allows them to avoid recurrent lateral ankle sprains and giving way episodes. To date, research has identified differences in perceptual (e.g. self-assessed disability), mechanical (e.g. ligament laxity), and sensorimotor (e.g. balance) outcomes between copers and those with CAI. However, the vast majority of these outcomes are considered research and/or laboratory based and thus impractical for most clinicians to use …


Comparing Dominant And Non-Dominant Torque And Work Using Biodex 3 Isokinetic Protocol For Knee Flexors And Extensors, Joshua Sparks, Jeremy Carter, Kelly Brooks Nov 2011

Comparing Dominant And Non-Dominant Torque And Work Using Biodex 3 Isokinetic Protocol For Knee Flexors And Extensors, Joshua Sparks, Jeremy Carter, Kelly Brooks

International Journal of Exercise Science: Conference Proceedings

INTRODUCTION. There is often a misconception when looking at comparing dominant and non-dominant limbs of any sort. Although there will be a lack of control in non-dominant limbs compared to dominant, the amount of torque and power associated with each limb may be equal; even so, there may be an instance of bilateral deficit, where even though the dominant limb may be used to do work on a specific limb, the non-dominant limb may still receive strength benefits. PURPOSE. The main purpose of this study is to directly relate ability (torque and total work) in both dominant and non-dominate limbs …


Influences On Pulmonary And Muscular V’O2-Kinetics, Uwe Drescher, Uwe Hoffmann Nov 2011

Influences On Pulmonary And Muscular V’O2-Kinetics, Uwe Drescher, Uwe Hoffmann

International Journal of Exercise Science: Conference Proceedings

Introduction

Muscular and respiratory V’O2-kinetics are influenced by many factors. At cellular level muscular V’O2 (V’O2musc) is affected by O2-delivery and O2-consumption. Further, these factors can be divided into muscle perfusion, capillary density, enzyme activity, mitochondrial proliferation, muscle fiber composition and some more.

Focusing on the difference between V’O2resp and V’O2musc the venous blood volume, the venous O2-stores and the dynamics of cardiac output can be identified as influences. These influences result in a time delay and a distortion of V’O2resp. Usually exercise step responses are used for estimating V’O2resp-kinetics. But it has to be recognized, that V’O2resp may be …


Micro-Fracture Simulation In Human Vertebral Body Due To Weight Lifting, Harcharan S. Ranu Nov 2011

Micro-Fracture Simulation In Human Vertebral Body Due To Weight Lifting, Harcharan S. Ranu

International Journal of Exercise Science: Conference Proceedings

Abstract Lumbar vertebrae are a heavily loaded component of the human body. They are subjected to repetitive loading in daily activities. However, limited information on failure mechanism of lumbar vertebrae are available to date. Thus, the need to develop an analytical model to predict stress-fracture characteristics of vertebral body. A linear elastic fracture mechanics approach has been considered and a mathematical model has been proposed so that the predictions can be made more easily related to the occurrence of injury. Study reveals that for a person weighing 1334 N and lifting a weight of 345 kg during squat exercise causes …


Injury Simulation In Female Gymnasts, Harcharan S. Ranu Nov 2011

Injury Simulation In Female Gymnasts, Harcharan S. Ranu

International Journal of Exercise Science: Conference Proceedings

Abstract Female gymnasts often place un-physiological extreme repetitive loading on their bodies during the common maneuvers characteristic of this sport. Thus, it was necessity to provide quantitative and qualitative analyses of impact behavior of feet of gymnasts. The response of fracture or injury due to jumping is also important in designing safety equipment related to sports. A linear elastic fracture mechanics approach has been used for this analysis. Typical behavior of crack growth rate for a force of F= 6.1 KN and m being 1.25, revealed that 6 landings were sufficient to initiate micro-fracture of bone due to landing after …


A Leucine-Enriched Diet Enhances Overload-Induced Growth And Markers Of Protein Synthesis In Aged Rat Skeletal Muscle, Rengfei Shi, Hoke Whitworth, William Mixon, Scott E. Gordon Nov 2011

A Leucine-Enriched Diet Enhances Overload-Induced Growth And Markers Of Protein Synthesis In Aged Rat Skeletal Muscle, Rengfei Shi, Hoke Whitworth, William Mixon, Scott E. Gordon

International Journal of Exercise Science: Conference Proceedings

Introduction: The hypertrophic response to overload in fast-twitch skeletal muscle is impaired in aged humans and rats, and impaired protein synthesis pathway activation is hypothesized to be a contributing factor. Muscle growth occurs when protein synthesis exceeds protein degradation. Dietary supplementation of the essential amino acid leucine has been shown to enhance protein synthesis in both young and aged skeletal muscle. Leucine acts in part by activating mammalian target of rapamycin (mTOR; a key upstream regulator of protein synthesis pathways) as well as by attenuating the activation of 5'-AMP-activated protein kinase (AMPK; a negative regulator of mTOR and protein synthesis). …


A Leucine-Enriched Diet Enhances Overload-Induced Growth And Suppresses Markers Of Protein Degradation In Aged Rat Skeletal Muscle, Scott E. Gordon, William Mixon, Hoke Whitworth, Rengfei Shi Nov 2011

A Leucine-Enriched Diet Enhances Overload-Induced Growth And Suppresses Markers Of Protein Degradation In Aged Rat Skeletal Muscle, Scott E. Gordon, William Mixon, Hoke Whitworth, Rengfei Shi

International Journal of Exercise Science: Conference Proceedings

Introduction: The hypertrophic response to overload in fast-twitch skeletal muscle is impaired in aged humans and rats, and upregulation of protein degradation pathways are hypothesized to be a contributing factor. Muscle growth occurs when protein synthesis is greater than protein degradation. Dietary supplementation of the essential amino acid leucine has been shown to reduce protein degradation in both young and aged skeletal muscle. Specifically, leucine acts in part by attenuating 5'-AMP-activated protein kinase (AMPK) activation as well as the translocation of the forkhead box transcription factor 3A (FoxO3, known to promote transcription of mRNAs encoding degradation pathway proteins) to the …


Isokinetic Muscle Strength And Fatigue Evaluation Following A Combined Aerobic And Resistance Training Program On A Gravity Independent Flywheel Device, Joshua A. Cotter, Tomasz Owerkowicz, Alvin M. Yu, Marinelle L. Camilon, Theresa Hoang, Per A. Tesch, Vincent J. Caiozzo, Gregory R. Adams Nov 2011

Isokinetic Muscle Strength And Fatigue Evaluation Following A Combined Aerobic And Resistance Training Program On A Gravity Independent Flywheel Device, Joshua A. Cotter, Tomasz Owerkowicz, Alvin M. Yu, Marinelle L. Camilon, Theresa Hoang, Per A. Tesch, Vincent J. Caiozzo, Gregory R. Adams

International Journal of Exercise Science: Conference Proceedings

Exposure to microgravity imposes changes on the musculoskeletal and cardiovascular systems leading to decreases in aerobic capacity, muscular strength, and muscular fatigue (1). Anti-gravity muscles, those that play a postural role in a standard gravity environment such as the soleus and quadriceps, are most affected by microgravity (2) with nearly all musculature affected with extended spaceflight (3). The multi-mode exercise device (M-MED) is a gravity independent device that provides both high force resistance type and low force aerobic type modes of exercise. Consequently, the M-MED has the ability to enhance both skeletal muscle function through resistance training exercises as well …


Genetic Regulation Of Myofiber Hypertrophy?, Anna Thalacker-Mercer, Xiangqin Cui, Michael Stec, Edward Merritt, Marcas Bamman Nov 2011

Genetic Regulation Of Myofiber Hypertrophy?, Anna Thalacker-Mercer, Xiangqin Cui, Michael Stec, Edward Merritt, Marcas Bamman

International Journal of Exercise Science: Conference Proceedings

Introduction. Progressive, resistance exercise training (RT) induces skeletal muscle hypertrophy, increases strength, power, and quality of muscle, and is potentially the most promising method to regenerate and re-grow muscle in populations suffering from involuntary atrophy. However, we have previously shown that there is a large degree of intersubject variability for myofiber hypertrophy in response to RT with adults having no response [-16μm2 (mean myofiber growth), Non], a modest response (1111μm2, Mod), or an extreme hypertrophic response (2475μm2, Xtr). Underlying mechanisms for this differential growth response are largely unknown. Therefore, the purpose of this study was to determine whether differences in …