1,456 results on '"Buffering"'
Search Results
102. Multistate modeling of Florida scrub‐jay adult survival and breeding transitions.
- Author
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Breininger, David R., Carter, Geoffrey M., Legare, Stephanie A., Payne, William V., Stolen, Eric D., Breininger, Daniel J., and Lyon, James E.
- Subjects
FAMILY size ,ENDANGERED species ,PARENTAL death ,PARAMETERS (Statistics) ,WILDLIFE conservation ,SURVIVAL analysis (Biometry) ,HABITATS - Abstract
Adult nonbreeders are important for the stability and conservation of many species despite that their functional roles are often undervalued. Nonbreeders can buffer breeding population sizes and help their kin raise new generations of offspring, but in high numbers can compete and have negative effects. Long‐term studies are useful for elucidating relationships among nonbreeder population parameters, such as density, survival, and transitions to breeding status. Florida scrub‐jays are cooperative breeders where young delay breeding often for many years and are at risk of extinction across most of their range. Our objectives were to estimate how population covariates (pair density and mean family size) influenced Florida scrub‐jay adult nonbreeder survival and breeding transitions using long‐term data of uniquely marked birds and multistate capture–recapture models. The evolution and maintenance of Florida scrub‐jay delayed breeding has been attributed to living in crowded and sharply delineated habitat at Archbold Biological Station, the site of longest long‐term study. Contrastingly, most habitat we studied had a dynamic mixture of habitat quality with mean family sizes and pair densities much lower than the stable, optimal habitat at Archbold Biological Station. Despite having densities below carrying capacity, Florida scrub‐jays still delayed breeding. We found that greater mean family size was associated with greater breeder survival, possibly because nonbreeders contributed to predator detection and territory defense. Nonbreeder‐to‐breeder transitions increased with increased annual breeder mortality rates but were influenced little by population densities. Most Florida scrub‐jays became breeders by replacing dead breeders within occupied territories, and many male and female nonbreeders inherited their territories upon the death of their parents. Nonbreeders buffered changes in the breeding population supporting greater recognition of nonbreeder population roles within field and modeling studies. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
103. A Low Latency Adaptive Video Streaming Framework To Control The Congestion And Reduce The Switching Times Between Quality Levels.
- Author
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Alqhtani, Wafa A., Taha, Ashraf A., and Alsabaan, Maazen S.
- Abstract
Video streaming over the Internet is considered the most essential communication technology in recent years, especially with the spread of the SARS-CoV2 pandemic where the communication between people and the work via online videos. This technology faces various challenges that may be obstacles for the customer and the service provider to deliver videos with a flexible quality and without interruption. The high congestion value of the frames on the buffer of the client is one of these challenges. Consequently, the video latency is increased, and thus reduced the video throughput with more interruptions and low quality. The paper is suggested an adaptive video streaming framework by introducing a low latency in an online application to control the congestion and reduce switching times between levels to make video streaming more seamless. The low latency scheme aims to increase the bitrates to optimal values to avoid the congestion of frames on the buffer with a minimum delay value. Analyzing the video load based on three Parameters: latency, Buffering, and throughput of the dynamic system will control the congestion to reduce the switching between quality levels and consequently improve the performance. [ABSTRACT FROM AUTHOR]
- Published
- 2022
104. An Analysis of the Optimal Facility Location of Tourism Industry in Plain Region by Utilizing GIS.
- Author
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Chen, Yen-Chieh, Yao, Hsiao-Li, Weng, Shou-Der, and Tai, Yang-Fei
- Abstract
In this study, we utilize regional public facilities as the factors of evaluation criteria, apply buffering and weighted overlay analysis in GIS as the multi-criteria spatial information analysis tools, and take the Lanyang Plain, Yilan, Taiwan as the test area for the optimal facility location analysis of tourism industry. We take the "optimal service/influence distance" of each regional public facility from literature review as the radius of neighborhood for buffering and build the buffer objects in GIS. The process of weighted overlay analysis is conducted by using grid method. After a series of grid size testing, we find that while the grid size decreases to 320 m × 320 m, the distribution of grids with weighted overlay values is close to the distribution of all the buffer objects mentioned above. The distribution of grids with higher weighted overlap values obviously presents the optimal facility location of tourism industry that is apparently consistent with the distribution of the famous tour sites or facilities of tourism industry and the four to five star hotels. Therefore, we conclude that this optimal facility location model of tourism industry should be quite suitable for land use or site selection planning of tourism and relative industries. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
105. PLASMA LEVELS OF BUFFERED LIDOCAINE AND METABOLITE MONOETHYLGLYCINEXYLIDIDE (MEGX) COMPARED WITH A NON-BUFFERED ANALOG. PRELIMINARY RESULTS.
- Author
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TSVETANOV, Tsvetan and TOMOV, Desislav
- Subjects
LIQUID chromatography-mass spectrometry ,LIDOCAINE ,LOCAL anesthetics ,MANDIBULAR nerve ,NERVE block - Abstract
Introduction. Lidocaine is the most common local anesthetic used in dentistry. The aim of the current study was to assess plasma concentrations of Lidocaine (buffered and non-buffered) and metabolite Monoethylglycinexylidide (MEGX). Materials and methods: The study included 45 healthy patients followed during mandibular nerve block and oral surgery interventions. The blood samples were taken 30 minutes after anaesthesia, and plasma levels were measured by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode. Results and discussion: Median buffered lidocaine plasma levels (26 blood samples) at 30 minutes were 0.313±0.179 mg/L, while median non-buffered lidocaine plasma levels (19 blood samples) were 0.310±0.190 mg/L. Mean buffered monoethylglycinexylidide (MEGX) plasma levels (26 blood samples) at 30 minutes were 0.015± 0.013 mg/L, while mean non-buffered monoethylglycinexylidide (MEGX) plasma levels (19 blood samples) were 0.012±0.012 mg/L. Conclusions: No statistical difference in blood plasma levels between the mean values of buffered and nonbuffered lidocaine and its metabolite monoethylglycinexylidide (MEGX) (p > 0.05) was observed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
106. The influence of progressive-chronic and acute sodium bicarbonate supplementation on anaerobic power and specific performance in team sports: a randomized, double-blind, placebo-controlled crossover study
- Author
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Krzysztof Durkalec-Michalski, Paulina M. Nowaczyk, Jacek Adrian, Joanna Kamińska, and Tomasz Podgórski
- Subjects
Ergogenic support ,Buffering ,Acid-base balance ,Alkalizing agent ,Exercise performance ,Sports nutrition ,Nutrition. Foods and food supply ,TX341-641 ,Nutritional diseases. Deficiency diseases ,RC620-627 - Abstract
Abstract Background The aims of this study were to verify the effect of progressive-chronic and acute sodium bicarbonate (SB) supplementation on the anaerobic capacity, blood acid-base balance, and discipline-specific performance in team sports disciplines. Methods Twenty-four trained male field hockey players completed a randomized, placebo-controlled, crossover trial of either progressive-chronic (increments from 0.05 up to 0.2 g/kg) or an acute one-off dose (0.2 g/kg) supplementation protocol. Before and after treatments, athletes completed an exercise protocol that comprised of a discipline-specific field performance test conducted between two separate Wingate anaerobic tests (WAnTs). Results Progressive-chronic SB supplementation improved anaerobic capacity in the first bout of WAnTs, as observed based on an increase in mean power (MP: 575 ± 71 vs. 602 ± 67 W, p = 0.005, ~ + 4.7%), peak power (PP: 749 ± 94 vs. 777 ± 96 W, p = 0.002, ~ + 3.7%), power carry threshold (PCT) at 97%PP (727 ± 91 vs. 753 ± 93 W, p = 0.002, ~ + 3.6%) and average power over PCT (739 ± 94 vs. 765 ± 95 W, p = 0.001, ~ + 3.5%). Acute SB supplementation had no effect on anaerobic capacity. However, an improvement in time during discipline-specific field performance test was observed after progressive-chronic (919 ± 42 vs. 912 ± 27 s, p = 0.05; ~ − 0.8%) and acute (939 ± 26 vs. 914 ± 22 s, p = 0.006, ~ 2.7%) SB supplementation. Acute SB supplementation also improved post-exercise parameters of acid-base balance (based on blood pH, bicarbonate concentration and base excess) compared to no supplementation or placebo. Conclusions Our study indicates that both chronic and acute SB supplementation positively supports discipline-specific performance among field hockey athletes. Moreover, the chronic protocol supported anaerobic power indices before the inset of exercise-induced fatigue but had no significant impact afterwards. However, only the acute protocol significantly affected the buffering capacity, which can be used to determine athlete’s performance during high-intensity sporting events. This study design therefore highlighted that future studies focusing on sodium bicarbonate supplementation in team sports should concentrate on the efficiency of chronic and acute supplementation in varying time frames.
- Published
- 2020
- Full Text
- View/download PDF
107. Multistate modeling of Florida scrub‐jay adult survival and breeding transitions
- Author
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David R. Breininger, Geoffrey M. Carter, Stephanie A. Legare, William V. Payne, Eric D. Stolen, Daniel J. Breininger, and James E. Lyon
- Subjects
buffering ,delayed breeding ,long‐term studies ,nonbreeders ,population density ,Ecology ,QH540-549.5 - Abstract
Abstract Adult nonbreeders are important for the stability and conservation of many species despite that their functional roles are often undervalued. Nonbreeders can buffer breeding population sizes and help their kin raise new generations of offspring, but in high numbers can compete and have negative effects. Long‐term studies are useful for elucidating relationships among nonbreeder population parameters, such as density, survival, and transitions to breeding status. Florida scrub‐jays are cooperative breeders where young delay breeding often for many years and are at risk of extinction across most of their range. Our objectives were to estimate how population covariates (pair density and mean family size) influenced Florida scrub‐jay adult nonbreeder survival and breeding transitions using long‐term data of uniquely marked birds and multistate capture–recapture models. The evolution and maintenance of Florida scrub‐jay delayed breeding has been attributed to living in crowded and sharply delineated habitat at Archbold Biological Station, the site of longest long‐term study. Contrastingly, most habitat we studied had a dynamic mixture of habitat quality with mean family sizes and pair densities much lower than the stable, optimal habitat at Archbold Biological Station. Despite having densities below carrying capacity, Florida scrub‐jays still delayed breeding. We found that greater mean family size was associated with greater breeder survival, possibly because nonbreeders contributed to predator detection and territory defense. Nonbreeder‐to‐breeder transitions increased with increased annual breeder mortality rates but were influenced little by population densities. Most Florida scrub‐jays became breeders by replacing dead breeders within occupied territories, and many male and female nonbreeders inherited their territories upon the death of their parents. Nonbreeders buffered changes in the breeding population supporting greater recognition of nonbreeder population roles within field and modeling studies.
- Published
- 2022
- Full Text
- View/download PDF
108. The Magnitude of the Blood Acid-Base Response, but Not Time to Peak, Is Reliable Following the Ingestion of Acute, Individualized Sodium Citrate.
- Author
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Tinnion DJ, Dobson B, Hilton N, McNaughton LR, and Sparks SA
- Abstract
Enhanced buffering capacity following sodium citrate (SC) ingestion may be optimized when subsequent exercise commences at individual time-to-peak (TTP) alkalosis (blood pH or bicarbonate concentration [HCO3-]). While accounting for considerable interindividual variation in TTP (188-300 min), a reliable blood alkalotic response is required for practical use. This study evaluated the reliability of blood pH, HCO3-, and sodium (Na+) following acute SC ingestion. Fourteen recreationally active males ingested 0.4 or 0.5 g/kg body mass (BM) of SC on two occasions each and 0.07 g/kg BM of sodium chloride (control) once. Blood pH and HCO3- were measured for 4 hr postingestion. Blood pH and HCO3- displayed good reliability following 0.5 g/kg BM SC (r = .819, p = .002, standardized technical error [sTE] = 0.67 and r = .840, p < .001, sTE = 0.63, respectively). Following 0.4 g/kg BM SC, blood HCO3- retained good reliability (r = .771, p = .006, sTE = 0.78) versus moderate for blood pH (r = .520, p = .099, sTE = 1.36). TTP pH was moderately reliable following 0.5 (r = .676, p = .026, sTE = 1.05) and 0.4 g/kg BM SC (r = .679, p = .025, sTE = 0.91) versus poor for HCO3- following 0.5 (r = .183, p = .361, sTE = 5.38) and 0.4 g/kg BM SC (r = .290, p = .273, sTE = 2.50). Although the magnitude of (and displacement in) blood alkalosis, particularly HCO3-, appears reliable following potentially ergogenic doses of SC, strategies based on individual TTP cannot be recommended.
- Published
- 2024
- Full Text
- View/download PDF
109. Quantitative Service Reliability Assessment on Single and Multi Layer Networks
- Author
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Pandey, Harshit, Tan, Cher Ming, Barbosa, Simone Diniz Junqueira, Series Editor, Filipe, Joaquim, Series Editor, Kotenko, Igor, Series Editor, Sivalingam, Krishna M., Series Editor, Washio, Takashi, Series Editor, Yuan, Junsong, Series Editor, Zhou, Lizhu, Series Editor, Ghosh, Ashish, Series Editor, Minz, Sonajharia, editor, Karmakar, Sushanta, editor, and Kharb, Latika, editor
- Published
- 2019
- Full Text
- View/download PDF
110. Biogeochemical Processes and Inorganic Carbon Dynamics
- Author
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Middelburg, Jack J., Lohmann, Gerrit, Series Editor, Mysak, Lawrence A., Series Editor, Notholt, Justus, Series Editor, Rabassa, Jorge, Series Editor, Unnithan, Vikram, Series Editor, and Middelburg, Jack J.
- Published
- 2019
- Full Text
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111. Scaling nitrogen and carbon interactions: What are the consequences of biological buffering?
- Author
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Wullschleger, Stan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)]
- Published
- 2015
- Full Text
- View/download PDF
112. Invigorating entrepreneurial ecosystems : How bridging and buffering resource theories can help motivate entrepreneurialism
- Published
- 2020
- Full Text
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113. Exact Zoning Optimization Model for Marine Spatial Planning (MSP)
- Author
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Mohadese Basirati, Romain Billot, Patrick Meyer, and Erwan Bocher
- Subjects
marine spatial planning ,multi-objective integer linear optimization ,buffering ,interest ,compactness ,raster data ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Marine spatial planning (MSP) has recently attracted more attention as an efficient decision support tool. MSP is a strategic and long-term process gathering multiple competing users of the ocean with the objective to simplify decisions regarding the sustainable use of marine resources. One of the challenges in MSP is to determine an optimal zone to locate a new activity while taking into account the locations of the other existing activities. Most approaches to spatial zoning are formulated as non-linear optimization models involving multiple objectives, which are usually solved using stochastic search algorithms, leading to sub-optimal solutions. In this paper, we propose to model the problem as a Multi-Objective Integer Linear Program. The model is developed for raster data and it aims at maximizing the interest of the area of the zone dedicated to the new activity while maximizing its spatial compactness. We study two resolution methods: first, a weighted-sum of the two objectives, and second, an interactive approach based on an improved augmented version of the ϵ-constraint method, AUGMECON2. To validate and study the model, we perform experiments on artificially generated data. Our experimental study shows that AUGMECON2 represents the most promising approach in terms of relevance and diversity of the solutions, compactness, and computation time.
- Published
- 2021
- Full Text
- View/download PDF
114. Examining Practice Effects in a Randomized Controlled Trial: Daily Life Mindfulness Practice Predicts Stress Buffering Effects of Mindfulness Meditation Training.
- Author
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Manigault, Andrew W., Slutsky, Jeremiah, Raye, Julianna, and Creswell, John David
- Abstract
Objectives: Mindfulness practice is thought to underlie the therapeutic effects of mindfulness interventions. Yet, more research is needed to evaluate mindfulness practice effects and identify effective practice types. The present study examined the effects of two types of mindfulness practice (audio-guided and daily life mindfulness practice) on measures of stress and coping in a workplace sample. Methods: Employees from a digital marketing firm undergoing stressful organizational restructuring (n
final = 60; aged 21–57; 95.0% white; 66.7% women) were randomly assigned to a high- (1-day seminar plus 6-week practice) or low-dose (1-day seminar) mindfulness training program. Participants completed 3 days of ecological momentary assessments of stress/coping pre- and post-interventions. Audio-guided mindfulness practice was assessed by the number of audio-guided practice sessions completed during the intervention period; daily life mindfulness practice was indexed by how often participants reported applying mindfulness to daily activities during the intervention period. Results: Across the full sample, more frequent daily life mindfulness practice buffered against pre- to post-intervention increases in stress ratings (β = −.18, p =.002), stressor frequency (β = −.32, p <.001), and stressor intensity (β = −.27, p =.003), and decreases in successful coping (β =.25, p =.005). Comparable (but weaker) results were observed for audio-guided mindfulness practice (stress ratings: β = −.15, p =.013; stressor frequency: β = −.27, p <.001; stressor intensity: β = −.22, p =.015; successful coping: β =.17, p =.066). Conclusions: Much of the mindfulness meditation RCT literature to date has not measured or reported guided or daily life practices, and this work suggests that measuring both may be important for understanding the stress buffering effects of mindfulness meditation training. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
115. Why do states in conflict with each other also sustain resilient cooperation in international regulation? Britain and telegraphy, 1860s–1914.
- Author
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6, Perri and Heims, Eva
- Subjects
- *
INTERNATIONAL cooperation , *TELEGRAPH & telegraphy , *GOVERNMENT agencies , *PUBLIC understanding of science , *INTERNATIONAL relations theory - Abstract
This article compares the explanatory power of five mainstream theories from International Relations, political science and public management in understanding why – when they are engaged in deepening conflict and tension and even preparations for wars – states might simultaneously sustain deepening cooperation in global regulatory bodies. Analysis of explanatory power focuses on trade-offs among five key methodological virtues, and on buffering as an indicator of state unitariness. The theories are examined against the crucial case of one state's commitment to the first international regulatory regime, the International Telegraph Union (ITU) and the Submarine Cable Convention (SCC) of 1884, from the founding of the ITU in 1865 to the outbreak of the Great War. In this article, we use UK National Archives files to reconstruct Britain's decisions in telegraphy policy as our case of a state's decision-making. We focus on four key clusters of decisions, spanning three sub-periods. The study finds each of the theories can descriptively capture some developments in some sub-periods, but not for the reasons identified in the theory and without generality of application. It therefore provides the basis for future theoretical development work and demonstrates the value of theory comparison by analysis of trade-offs among methodological virtues. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
116. Complex Approach to the Control of Car Body Buffering in the Paint Shop
- Author
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Alszer, Sara, Krystek, Jolanta, Bysko, Szymon, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Szewczyk, Roman, editor, Zieliński, Cezary, editor, and Kaliczyńska, Małgorzata, editor
- Published
- 2018
- Full Text
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117. The Optimal Control of Storage for Arbitrage and Buffering, with Energy Applications
- Author
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Cruise, James, Zachary, Stan, Drobinski, Philippe, editor, Mougeot, Mathilde, editor, Picard, Dominique, editor, Plougonven, Riwal, editor, and Tankov, Peter, editor
- Published
- 2018
- Full Text
- View/download PDF
118. Buffering of pulp pH and its influence on process water chemistry during iron ore flotation.
- Author
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Min Tang and Qingfei Xiao
- Subjects
IRON ores ,WATER chemistry ,FLOTATION ,IRON oxides ,FERRIC oxide ,BUFFER solutions ,DISSOLVED air flotation (Water purification) - Abstract
It is inevitable for the occurrences of pulp pH buffering during pH control in flotation as the minerals with acidic/alkali properties tend to interact with pH modifiers and restore the pulp pH. This could result in some disturbing ions and alter the water/pulp chemistry. The purpose of this study was to identify the influences of pulp pH buffering on process water chemistry through a series of pH buffering tests, bench flotation experiments, ore dissolution tests, zeta potential measurement, and Xray diffraction (XRD) analysis. The built-up and distribution of the dominant cations in the process water from different locations in an industrial flotation system of the iron ore were analyzed and recorded by Inductively Coupled Plasma-Optical Emission (ICP-OES) at a period of about six months when the operations were stable. The data showed that a near five-minute buffer of pulp pH at a range from near 7.9 to 8.9 occurred before it reached a stable value. At this period, the dissolution of Ca/Mg from the iron ore was dominant. And, the pulp pH at a lower value tended to induce more dissolved Ca
2+ and Mg2+ ions. These divalent cations seem to have different influences on the flotation properties of iron oxides at the same concentrations, indicating a positive effect on the recovery of iron oxides with the presence of Mg2+ ions but an opposite effect if Ca2+ ions occurred. The presence of sulfate, however, tended to restore the floatability of silicate depressed by Ca2+ ions. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
119. Oxytocin, cortisol, and cognitive control during acute and naturalistic stress.
- Author
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Young Kuchenbecker, Shari, Pressman, Sarah D., Celniker, Jared, Grewen, Karen M., Sumida, Kenneth D., Jonathan, Naveen, Everett, Brendan, and Slavich, George M.
- Subjects
- *
CONTROL (Psychology) , *HYDROCORTISONE , *OXYTOCIN , *EMOTIONS , *NEUROHORMONES , *PSYCHOLOGICAL resilience , *ACUTE stress disorder - Abstract
Although stress is a strong risk factor for poor health, especially for women, it remains unclear how stress affects the key neurohormones cortisol and oxytocin, which influence stress-related risk and resilience. Whereas cortisol mediates energy mobilization during stress, oxytocin has anti-inflammatory, anxiolytic, and analgesic effects that support social connection and survival across the lifespan. However, how these neurohormones interrelate and are associated with cognitive control of emotional information during stress remains unclear. To address these issues, we recruited 37 college-aged women (Mage = 19.19, SD = 1.58) and randomly assigned each to a one-hour experimental session consisting of either an acute stress (emotionally stressful video) or control (non-stressful video) condition in a cross-sectional manner across the semester. Salivary cortisol and oxytocin samples were collected at baseline and after the video, at which point participants also completed measures assessing affect and an emotional Stroop task. As hypothesized, the emotional stressor induced negative emotions that were associated with significant elevations in cortisol and faster Stroop reaction times. Moreover, higher baseline oxytocin predicted greater positive affect after the stressor and also better cognitive accuracy on the Stroop. Analyses examining the naturalistic stress effects revealed that basal oxytocin levels rose steeply three weeks before the semester's end, followed by rising cortisol levels one week later, with both neurohormones remaining elevated through the very stressful final exam period. Considered together, these data suggest that women's collective experiences of stress may be potentially buffered by a synchronous oxytocin surge that enhances cognitive accuracy and reduces stress "when the going gets tough". [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
120. Measures of excess V̇CO2 and recovery V̇CO2 as indices of performance fatigability during exercise: a pilot study.
- Author
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Wooten, Liana C., Neville, Brian T., and Keyser, Randall E.
- Subjects
EXERCISE intensity ,OXYGEN consumption ,EXERCISE tests ,ANAEROBIC metabolism ,PILOT projects ,ANAEROBIC capacity ,SKELETAL muscle ,CARBON dioxide - Abstract
Background: The severity of performance fatigability and the capacity to recover from activity are profoundly influenced by skeletal muscle energetics, specifically the ability to buffer fatigue-inducing ions produced from anaerobic metabolism. Mechanisms responsible for buffering these ions result in the production of excess carbon dioxide (CO
2 ) that can be measured as expired CO2 ( V ̇ CO2 ) during cardiopulmonary exercise testing (CPET). The primary objective of this study was to assess the feasibility of select assessment procedures for use in planning and carrying out interventional studies, which are larger interventional studies investigating the relationships between CO2 expiration, measured during and after both CPET and submaximal exercise testing, and performance fatigability. Methods: Cross-sectional, pilot study design. Seven healthy subjects (30.7±5.1 years; 5 females) completed a peak CPET and constant work-rate test (CWRT) on separate days, each followed by a 10-min recovery then 10-min walk test. Oxygen consumption ( V ̇ O2 ) and V ̇ CO2 on- and off-kinetics (transition constant and oxidative response index), excess- V ̇ CO2 , and performance fatigability severity scores (PFSS) were measured. Data were analyzed using regression analyses. Results: All subjects that met the inclusion/exclusion criteria and consented to participate in the study completed all exercise testing sessions with no adverse events. All testing procedures were carried out successfully and outcome measures were obtained, as intended, without adverse events. Excess- V ̇ CO2 accounted for 61% of the variability in performance fatigability as measured by V ̇ O2 on-kinetic ORI (ml/s) (R2 =0.614; y = 8.474x − 4.379, 95% CI [0.748, 16.200]) and 62% of the variability as measured by PFSS (R2 =0.619; y = − 0.096x + 1.267, 95% CI [−0.183, −0.009]). During CPET, V ̇ CO2 -off ORI accounted for 70% (R2 =0.695; y = 1.390x − 11.984, 95% CI [0.331, 2.449]) and V ̇ CO2 -off Kt for 73% of the variability in performance fatigability measured by V ̇ O2 on-kinetic ORI (ml/s) (R2 =0.730; y = 1.818x − 13.639, 95% CI [0.548, 3.087]). Conclusion: The findings of this study suggest that utilizing V ̇ CO2 measures may be a viable and useful addition or alternative to V ̇ O2 measures, warranting further study. While the current protocol appeared to be satisfactory, for obtaining select cardiopulmonary and performance fatigability measures as intended, modifications to the current protocol to consider in subsequent, larger studies may include use of an alternate mode or measure to enable control of work rate constancy during performance fatigability testing following initial CPET. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
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121. Forest microclimates and climate change: Importance, drivers and future research agenda.
- Author
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De Frenne, Pieter, Lenoir, Jonathan, Luoto, Miska, Scheffers, Brett R., Zellweger, Florian, Aalto, Juha, Ashcroft, Michael B., Christiansen, Ditte M., Decocq, Guillaume, De Pauw, Karen, Govaert, Sanne, Greiser, Caroline, Gril, Eva, Hampe, Arndt, Jucker, Tommaso, Klinges, David H., Koelemeijer, Irena A., Lembrechts, Jonas J., Marrec, Ronan, and Meeussen, Camille
- Subjects
- *
FOREST microclimatology , *CLIMATE change , *FOREST biodiversity , *FOREST mapping , *ECOSYSTEM services , *SPATIAL variation - Abstract
Forest microclimates contrast strongly with the climate outside forests. To fully understand and better predict how forests' biodiversity and functions relate to climate and climate change, microclimates need to be integrated into ecological research. Despite the potentially broad impact of microclimates on the response of forest ecosystems to global change, our understanding of how microclimates within and below tree canopies modulate biotic responses to global change at the species, community and ecosystem level is still limited. Here, we review how spatial and temporal variation in forest microclimates result from an interplay of forest features, local water balance, topography and landscape composition. We first stress and exemplify the importance of considering forest microclimates to understand variation in biodiversity and ecosystem functions across forest landscapes. Next, we explain how macroclimate warming (of the free atmosphere) can affect microclimates, and vice versa, via interactions with land‐use changes across different biomes. Finally, we perform a priority ranking of future research avenues at the interface of microclimate ecology and global change biology, with a specific focus on three key themes: (1) disentangling the abiotic and biotic drivers and feedbacks of forest microclimates; (2) global and regional mapping and predictions of forest microclimates; and (3) the impacts of microclimate on forest biodiversity and ecosystem functioning in the face of climate change. The availability of microclimatic data will significantly increase in the coming decades, characterizing climate variability at unprecedented spatial and temporal scales relevant to biological processes in forests. This will revolutionize our understanding of the dynamics, drivers and implications of forest microclimates on biodiversity and ecological functions, and the impacts of global changes. In order to support the sustainable use of forests and to secure their biodiversity and ecosystem services for future generations, microclimates cannot be ignored. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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- View/download PDF
122. Buffered 2% articaine versus non-buffered 4% articaine in maxillary infiltration: randomized clinical trial.
- Author
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Amorim, Klinger Souza, Fontes, Vanessa Tavares Silva, Gercina, Anne Caroline, Groppo, Francisco Carlos, and Souza, Liane Maciel Almeida
- Subjects
- *
CLINICAL trials , *LOCAL anesthesia , *LOCAL anesthetics , *INJECTIONS , *CROSSOVER trials , *PAIN management - Abstract
Objectives: This randomized, triple-blind, crossover clinical trial aimed to evaluate the efficacy, onset, length of pulp and soft tissue anesthesia, and pain during injection of 2% buffered articaine and 4% non-buffered articaine solutions. Methods: Each volunteer received two maxillary supraperiosteal anesthesia infiltrations in canine area. The infiltrations were performed at two different sessions using a different local anesthetic solution for each session, and the anesthetic injection speed was always 1 mL/min. The assessment of the onset and length of pulpal and soft tissue anesthesia was performed with the pulp electrical test "pulp tester" and the esthesiometer kit, respectively. Volunteers marked pain during injection on a visual analog scale (VAS). The anesthetics solutions pH was evaluated through the pH meter equipment. Results: There was no difference between the two anesthetic solutions (onset of soft tissue anesthesia, p = 0.5386; length of soft tissue anesthesia, p = 0.718; onset of pulpal anesthesia, p = 0.747; length of pulpal anesthesia, p = 0.375), except for pain during the injection which was lower when buffered 2% articaine was used (p = 0.001) and the pH. The pH analysis revealed that the solutions differed from one another (p < 0.01). Conclusion: The 2% buffered articaine solution provided the same anesthetic properties then 4% unbuffered articaine with a great reduction in pain during injection. Clinical relevance: The possibility of use 2% buffered articaine solution instead of 4% articaine maintaining the same anesthetic properties with a great reduction in pain during injection and half of the anesthetic salt concentration. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
123. Protective Parenting Behavior Buffers the Impact of Racial Discrimination on Depression Among Black Youth.
- Author
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Lei, Man Kit, Lavner, Justin A., Carter, Sierra E., Hart, Ariel R., and Beach, Steven R. H.
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PARENTING , *RACE discrimination , *BLACK youth , *AFRICAN American families , *BLACK people - Abstract
The adverse impact of racial discrimination on youth, and particularly its impact on the development of depressive symptoms, has prompted attention regarding the potential for family processes to protect youth from these erosive effects. Evidence from non-experimental studies indicates that protective parenting behavior (PPB) which occurs naturally in many Black families can buffer youth from the negative impact of racial discrimination. Of interest is whether "constructed resilience" developed through family-centered prevention programming can add to this protective buffering. The current paper examines the impact of constructed resilience in the form of increased protective parenting using 295 families randomly assigned either to a control condition or to the Protecting Strong African American Families (ProSAAF) program, a family-based prevention program previously shown to enhance protective parenting. We found that baseline racial discrimination was predictive of change in youths' depressive symptoms across the pre–post study period. Second, we found that parents participating in ProSAAF, relative to those randomly assigned to the control group, significantly improved in their use of an intervention targeting PPB. Third, we found a significant effect of change in PPB on the association of discrimination with change in depressive symptoms. Finally, we found that ProSAAF participation buffered the impact of racial discrimination on change in depressive symptoms through change in PPB. Results provide experimental support for constructed resilience in the form of change in PPB and call for increased attention to the development of family-based intervention programs to protect Black youth from the pernicious effects of racial discrimination. [ABSTRACT FROM AUTHOR]
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- 2021
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124. The effect of β-alanine supplementation on high intensity cycling capacity in normoxia and hypoxia.
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Patel, Kiran Akshay, Farias de Oliveira, Luana, Sale, Craig, and James, Ruth M
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EXERCISE tolerance , *NEUROPEPTIDES , *EXERCISE physiology , *CYCLING , *ALANINE , *DIETARY supplements , *RANDOMIZED controlled trials , *EXERCISE intensity , *DESCRIPTIVE statistics , *LACTATES , *STATISTICAL sampling , *HYPOXEMIA - Abstract
The availability of dietary beta-alanine (BA) is the limiting factor in carnosine synthesis within human muscle due to its low intramuscular concentration and substrate affinity. Carnosine can accept hydrogen ions (H+), making it an important intramuscular buffer against exercise-induced acidosis. Metabolite accumulation rate increases when exercising in hypoxic conditions, thus an increased carnosine concentration could attenuate H+ build-up when exercising in hypoxic conditions. This study examined the effects of BA supplementation on high intensity cycling capacity in normoxia and hypoxia. In a double-blind design, nineteen males were matched into a BA group (n = 10; 6.4 g·d−1) or a placebo group (PLA; n = 9) and supplemented for 28 days, carrying out two pre- and two post-supplementation cycling capacity trials at 110% of powermax, one in normoxia and one in hypoxia (15.5% O2). Hypoxia led to a 9.1% reduction in exercise capacity, but BA supplementation had no significant effect on exercise capacity in normoxia or hypoxia (P > 0.05). Blood lactate accumulation showed a significant trial x time interaction post-supplementation (P = 0.016), although this was not significantly different between groups. BA supplementation did not increase high intensity cycling capacity in normoxia, nor did it improve cycling capacity in hypoxia even though exercise capacity was reduced under hypoxic conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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125. Doubling of Muscle Carnosine Concentration Does Not Improve Laboratory 1-Hr Cycling Time-Trial Performance.
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Weiliang Chung, Baguet, Audrey, Bex, Tine, Bishop, David J., and Derave, Wim
- Subjects
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ALANINE , *ANALYSIS of variance , *ATHLETIC ability , *BICARBONATE ions , *CYCLING , *HEART beat , *HYDROGEN-ion concentration , *LACTATES , *NEUROPEPTIDES , *NUCLEAR magnetic resonance spectroscopy , *PLACEBOS , *PROBABILITY theory , *QUESTIONNAIRES , *RESEARCH funding , *T-test (Statistics) , *ERGOGENIC aids , *RANDOMIZED controlled trials , *REPEATED measures design , *OXYGEN consumption , *ERGOMETRY , *SKELETAL muscle , *DIARY (Literary form) - Abstract
Muscle carnosine loading through chronic oral beta-alanine supplementation has been shown to be effective for short-duration, high-intensity exercise. This randomized, placebo-controlled study explored whether the ergogenic effect of beta-alanine supplementation is also present for longer duration exercise. Subjects (27 well-trained cyclists/triathletes) were supplemented with either beta-alanine or placebo (6.4 g/day) for 6 weeks. Time to completion and physiological variables for a 1-hr cycling time-trial were compared between pre and postsupplementation. Muscle carnosine concentration was also assessed via proton magnetic resonance spectroscopy before and after supplementation. Following beta-alanine supplementation, muscle carnosine concentration was increased by 143 ± 151% (mean ± SD; p < .001) in the gastrocnemius and 161 ± 56% (p < .001) in the soleus. Postsupplementation time trial performance was significantly slower in the placebo group (60.6 ± 4.4–63.0 ± 5.4 min; p < .01) and trended toward a slower performance following beta-alanine supplementation (59.8 ± 2.8–61.7 ± 3.0 min; p = .069). We found an increase in lactate/proton concentration ratio following beta-alanine supplementation during the time-trial (209.0 ± 44.0 (beta-alanine) vs. 161.9 ± 54.4 (placebo); p < .05), indicating that a similar lactate concentration was accompanied by a lower degree of systemic acidosis, even though this acidosis was quite moderate (pH ranging from 7.30 to 7.40). In conclusion, chronic beta-alanine supplementation in well-trained cyclists had a very pronounced effect on muscle carnosine concentration and a moderate attenuating effect on the acidosis associated with lactate accumulation, yet without affecting 1-h time-trial performance under laboratory conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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126. Effect of Sodium Bicarbonate and Beta-Alanine on Repeated Sprints During Intermittent Exercise Performed in Hypoxia.
- Author
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Saunders, Bryan, Sale, Craig, Harris, Roger C., and Sunderland, Caroline
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ALANINE , *ANALYSIS of variance , *HYPOXEMIA , *ATHLETIC ability , *BODY weight , *CLINICAL trials , *EXERCISE , *RUNNING , *SODIUM bicarbonate , *STATURE , *TREADMILLS , *OXYGEN consumption , *DATA analysis software , *DESCRIPTIVE statistics - Abstract
Purpose: To investigate the separate and combined effects of sodium bicarbonate and beta-alanine supplementation on repeated sprints during simulated match play performed in hypoxia. Methods: Study A: 20 recreationally active participants performed two trials following acute supplementation with either sodium bicarbonate (0.3 g·kg-1 BM) or placebo (maltodextrin). Study B: 16 recreationally active participants were supplemented with either a placebo or beta-alanine for 5 weeks (6.4 g·day-1 for 4 weeks, 3.2 g·day-1 for 1 week), and performed one trial before supplementation (with maltodextrin) and two following supplementation (with sodium bicarbonate and maltodextrin). Trials consisted of 3 sets of 5 × 6 s repeated sprints performed during a football specific intermittent treadmill protocol performed in hypoxia (15.5% O2). Mean (MPO) and peak (PPO) power output were recorded as the performance measures. Results: Study A: Overall MPO was lower with sodium bicarbonate than placebo (p = .02, 539.4 ± 84.5 vs. 554.0 ± 84.6 W), although there was no effect across sets (all p > .05). Study B: There was no effect of beta-alanine, or cosupplementation with sodium bicarbonate, on either parameter, although there was a trend toward higher MPO with sodium bicarbonate (p = .07). Conclusions: The effect of sodium bicarbonate on repeated sprints was equivocal, although there was no effect of beta-alanine or cosupplementation with sodium bicarbonate. Individual variation may have contributed to differences in results with sodium bicarbonate, although the lack of an effect with beta-alanine suggests this type of exercise may not be influenced by increased buffering capacity. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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127. Take one for the team: on the time efficiency of application-level buffer-aided relaying in edge cloud communication.
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Li, Zheng, Millar-Bilbao, Francisco, Rojas-Durán, Gonzalo, and Ladra, Susana
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DATA packeting ,DATA transmission systems ,CLOUD computing ,DECODE & forward communication ,FAULT-tolerant computing ,ENERGY consumption ,EDGES (Geometry) - Abstract
Background: Adding buffers to networks is part of the fundamental advance in data communication. Since edge cloud computing is based on the heterogeneous collaboration network model in a federated environment, it is natural to consider buffer-aided data communication for edge cloud applications. However, the existing studies generally pursue the beneficial features of buffering at a cost of time, not to mention that many investigations are focused on lower-layer data packets rather than application-level communication transactions. Aims: Driven by our argument against the claim that buffers "can introduce additional delay to the communication between the source and destination", this research aims to investigate whether or not (and if yes, to what extent) the application-level buffering mechanism can improve the time efficiency in edge-cloud data transmissions. Method: To collect empirical evidence for the theoretical discussion, we built up a testbed to simulate a remote health monitoring system, and conducted both experimental and modeling investigations into the first-in-first-served (FIFS) and buffer-aided data transmissions at a relay node in the system. Results: An empirical inequality system is established for revealing the time efficiency of buffer-aided edge cloud communication. For example, given the reference of transmitting the 11th data entity in the FIFS manner, the inequality system suggests buffering up to 50 data entities into one transmission transaction on our testbed. Conclusions: Despite the trade-off benefits (e.g., energy efficiency and fault tolerance) of buffering data, our investigation argues that the buffering mechanism can also speed up data transmission under certain circumstances, and thus it would be worth taking data buffering into account when designing and developing edge cloud applications even in the time-critical context. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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128. Reinterpreting Fisher’s coordinated strategies: a longitudinal case study
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Stratton, Roy
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- 2018
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129. Buffered Local Anesthesia in Dentistry-A Review
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Pia., Joseph Changankary, Mitthra, Suresh, Anuradha, Balasubramanian, and Subbiya, Arunajetasan
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- 2019
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130. Capsule Size Alters the Timing of Metabolic Alkalosis Following Sodium Bicarbonate Supplementation
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India Middlebrook, Joe Peacock, Daniel J. Tinnion, Nicholas K. Leach, Nathan P. Hilton, Bryan Saunders, S. Andy Sparks, and Lars R. Mc Naughton
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buffering ,gastrointestinal disturbance ,performance ,acid base balance ,palatability ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Introduction: Sodium bicarbonate (NaHCO3) is a well-established nutritional ergogenic aid that is typically ingested as a beverage or consumed in gelatine capsules. While capsules may delay the release of NaHCO3 and reduce gastrointestinal (GI) side effects compared with a beverage, it is currently unclear whether the capsule size may influence acid–base responses and GI symptoms following supplementation.Aim: This study aims to determine the effects of NaHCO3 supplementation, administered in capsules of different sizes, on acid–base responses, GI symptoms, and palatability.Methods: Ten healthy male subjects (mean ± SD: age 20 ± 2 years; height 1.80 ± 0.09 m; weight 78.0 ± 11.9 kg) underwent three testing sessions whereby 0.3 g NaHCO3/kg of body mass was consumed in either small (size 3), medium (size 0), or large (size 000) capsules. Capillary blood samples were procured pre-ingestion and every 10 min post-ingestion for 180 min. Blood samples were analyzed using a radiometer (Radiometer ABL800, Denmark) to determine blood bicarbonate concentration ([HCO3-]) and potential hydrogen (pH). GI symptoms were measured using a questionnaire at the same timepoints, whereas palatability was recorded pre-consumption.Results: Capsule size had a significant effect on lag time (the time [HCO3-] changed, Tlag) and the timing of peak blood [HCO3-] (Tmax). Bicarbonate Tlag was significantly higher in the large-sized (28 ± 4 min) compared with the small-sized (13 ± 2 min) capsules (P = 0.009). Similarly, Tmax was significantly lower in the small capsule (94 ± 24 min) compared with both the medium-sized (141 ± 27 min; P < 0.001) and the large-sized (121 ± 29 min; P < 0.001) capsules. The GI symptom scores were similar for small-sized (3 ± 3 AU), medium-sized (5 ± 3 AU), and large-sized (3 ± 3 AU) capsules, with no significant difference between symptom scores (F = 1.3, P = 0.310). Similarly, capsule size had no effect on palatability (F = 0.8, P = 0.409), with similar scores between different capsule sizes.Conclusion: Small capsule sizes led to quicker Tlag and Tmax of blood [HCO3-] concentration compared to medium and large capsules, suggesting that individuals could supplement NaHCO3 in smaller capsules if they aim to increase extracellular buffering capacity more quickly.
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- 2021
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131. Integrative Omics Analysis Reveals a Limited Transcriptional Shock After Yeast Interspecies Hybridization
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Hrant Hovhannisyan, Ester Saus, Ewa Ksiezopolska, Alex J. Hinks Roberts, Edward J. Louis, and Toni Gabaldón
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hybridization ,yeast hybrid ,transcriptome shock ,allele-specific expression ,buffering ,Genetics ,QH426-470 - Abstract
The formation of interspecific hybrids results in the coexistence of two diverged genomes within the same nucleus. It has been hypothesized that negative epistatic interactions and regulatory interferences between the two sub-genomes may elicit a so-called genomic shock involving, among other alterations, broad transcriptional changes. To assess the magnitude of this shock in hybrid yeasts, we investigated the transcriptomic differences between a newly formed Saccharomyces cerevisiae × Saccharomyces uvarum diploid hybrid and its diploid parentals, which diverged ∼20 mya. RNA sequencing (RNA-Seq) based allele-specific expression (ASE) analysis indicated that gene expression changes in the hybrid genome are limited, with only ∼1–2% of genes significantly altering their expression with respect to a non-hybrid context. In comparison, a thermal shock altered six times more genes. Furthermore, differences in the expression between orthologous genes in the two parental species tended to be diminished for the corresponding homeologous genes in the hybrid. Finally, and consistent with the RNA-Seq results, we show a limited impact of hybridization on chromatin accessibility patterns, as assessed with assay for transposase-accessible chromatin using sequencing (ATAC-Seq). Overall, our results suggest a limited genomic shock in a newly formed yeast hybrid, which may explain the high frequency of successful hybridization in these organisms.
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- 2020
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132. SAHCI: Scheduling Approach for Heterogeneous Content-Centric IoT Applications
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Fadi Al-Turjman, Enver Ever, Yousaf Bin Zikria, Sung Won Kim, and Abdulmalek Elmahgoubi
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Networks ,scheduling ,simulation quality of service ,IoT ,buffering ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The Internet of Things (IoT) is one of the dominating paradigms of the new era with its abilities to provide ubiquitous intelligence and pervasive interconnections to diverse physical objects. With the advancements, such as new generation 5G communication and cloud/edge computing-based paradigms, the degree of domination is expected to further increase. Therefore, improvements for quality of service have become a critical issue. Traditional packets scheduling algorithms cannot meet the requirements of the large-scale IoT systems. In this paper, a novel scheduling approach is proposed for different data classes (types) to be exchanged between heterogeneous nodes of a generic IoT infrastructure. The possible ways of organizing these classes depending on different metrics, such as time latency, reliability, and data loss, are investigated. The proposed approach has the advantage of being able to tune the priorities and network characteristics to reach a specifically desired performance state. Since each type of packets is considered separately, it is possible to prioritize them, by tuning the related parameters, which changes the priorities between packets. The numerical results presented show that the new approach performs better than the existing typical scheduling approaches. The developed approach can be used in the various IoT applications with the support of 5G communication and edge computing, such as agriculture, wearables, connected cars, smart retail, and smart cities.
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- 2019
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133. Buffering Performance Analysis of an Ostrich-like Leg Based on a Seven-Link Parallel Mechanism
- Author
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Daming Nie, Ruilong Du, Jiangren Tian, Pu Zhang, Fangyan Shen, Jason Gu, and Yili Fu
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biomimetic robotics ,parallel mechanism ,buffering ,leaf spring ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
As one of the fastest running animals on land, the ostrich’s excellent athletic ability benefits from its unique leg structure. Based on the idea of bionics, this paper intends to obtain a kind of robotic leg structure with a similar buffering capacity to that of the ostrich. For this purpose, the structural characteristics of a seven-link parallel mechanism are analyzed firstly, having some specific features similar to ostrich legs, such as the center of mass (COM) located at the root of the leg, a large folding/unfolding ratio, and so on. Then, the kinematic model of the bionic leg is established, and the energy storage of the flexible parts of the leg is investigated. Finally, an impact experiment of the structure onto the ground is carried out to verify the accuracy of the established kinematic model. This paper systematically reveals the nonlinear law of the elasticity of an ostrich-like leg and provides the buffering performance characteristics of the leg in the process of hitting the ground, based on its elastic properties by the kinematic model and the experiment.
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- 2022
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134. Effect of Beta-Alanine Supplementation on 800-m Running Performance.
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Ducker, Kagan J., Dawson, Brian, and Wallman, Karen E.
- Subjects
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ALANINE , *ANALYSIS of covariance , *ANALYSIS of variance , *STATISTICAL correlation , *EXERCISE , *HYDROGEN-ion concentration , *HEALTH outcome assessment , *PLACEBOS , *PROBABILITY theory , *RUNNING , *STATISTICS , *T-test (Statistics) , *DATA analysis , *EFFECT sizes (Statistics) , *ERGOGENIC aids , *BODY movement , *RANDOMIZED controlled trials , *PRE-tests & post-tests , *REPEATED measures design , *DATA analysis software , *DIARY (Literary form) - Abstract
Beta-alanine supplementation has been shown to improve exercise performance in short-term, high-intensity efforts. Purpose: The aim of this study was to assess if beta-alanine supplementation could improve 800 m track running performance in male recreational club runners (n = 18). Methods: Participants completed duplicate trials (2 presupplementation, 2 postsupplementation) of an 800 m race, separated by 28 days of either beta-alanine (n = 9; 80 mg·kg-1BM·day-1) or placebo (n = 9) supplementation. Results: Using ANCOVA (presupplementation times as covariate), postsupplementation race times were significantly faster following beta-alanine (p = .02), with post- versus presupplementation race times being faster after beta-alanine (-3.64 ± 2.70 s, -2.46 ± 1.80%) but not placebo (-0.59 ± 2.54 s, -0.37 ± 1.62%). These improvements were supported by a moderate effect size (d = 0.70) and a very likely (99%) benefit in the beta-alanine group after supplementation. Split times (ANCOVA) at 400 m were significantly faster (p = .02) postsupplementation in the beta-alanine group, compared with placebo. This was supported by large effect sizes (d = 1.05-1.19) and a very likely (99%) benefit at the 400 and 800 m splits when comparing pre- to postsupplementation with beta-alanine. In addition, the first and second halves of the race were faster post- compared with presupplementation following beta-alanine (1st half -1.22 ± 1.81 s, likely 78% chance of benefit; 2nd half -2.38 ± 2.31 s, d = 0.83, very likely 98% chance of benefit). No significant differences between groups or pre- and postsupplementation were observed for postrace blood lactate and pH. Conclusion: Overall, 28 days of beta-alanine supplementation (80 mg·kg-1BM·day-1) improved 800 m track performance in recreational club runners. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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135. Effect of Beta-Alanine Supplementation on 2,000-m Rowing-Ergometer Performance.
- Author
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Ducker, Kagan J., Dawson, Brian, and Wallman, Karen E.
- Subjects
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ALANINE , *ANALYSIS of variance , *ATHLETIC ability , *STATISTICAL correlation , *HYDROGEN-ion concentration , *LACTATES , *PLACEBOS , *PROBABILITY theory , *ROWING , *STATISTICS , *T-test (Statistics) , *DATA analysis , *EFFECT sizes (Statistics) , *ERGOGENIC aids , *RANDOMIZED controlled trials , *ELITE athletes , *DATA analysis software , *DIARY (Literary form) - Abstract
Beta-alanine supplementation has been shown to improve exercise performance in short-term high-intensity efforts. However, whether supplementation with beta-alanine is ergogenic to actual sporting events remains unclear and should be investigated in field testing or race simulations. Purpose: The aim of this study was to assess if beta-alanine supplementation could improve 2,000-m rowing-ergometer performance in well-trained male rowers. Methods: Participants (N = 16) completed duplicate trials (2 × before supplementation and 2 × after supplementation) of a 2,000-m rowing-ergometer race separated by 28 days of either beta-alanine (n = 7; 80 mg · kg–1 BM · d–1) or placebo (n = 9; glucose) supplementation. Results: Beta-alanine group (pooled) race times improved by 2.9 ± 4.1 s and placebo group slowed by 1.2 ± 2.9 s, but these results were inconclusive for performance enhancement (p = .055, ES = 0.20, smallest worthwhile change = 49% beneficial). Racesplit times and average power outputs only significantly improved with beta-alanine at the 750-m (time –0.7 s, p = .01, power +3.6%, p = .03) and 1,000-m (time –0.5 s, p = .01, power +2.9%, p = .02) distances. Blood La– and pH postrace values were not different between groups before or after supplementation. Conclusions:Overall, 28 d of beta-alanine supplementation with 80 mg · kg–1 BM · d–1 (~7 g/d) did not conclusively improve 2,000-m rowing-ergometer performance in well-trained rowers. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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136. Systemic signalling and local effectors in developmental stability, body symmetry, and size
- Author
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Sergio Juarez-Carreño, Javier Morante, and Maria Dominguez
- Subjects
robustness ,fluctuating asymmetry ,environmental stress ,somatic mutations ,developmental stability ,buffering ,neuroendocrine signaling ,Dilp8 ,Lgr3 ,relaxin ,IGF ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Symmetric growth and the origins of fluctuating asymmetry are unresolved phenomena of biology. Small, and sometimes noticeable, deviations from perfect bilateral symmetry reflect the vulnerability of development to perturbations. The degree of asymmetry is related to the magnitude of the perturbations and the ability of an individual to cope with them. As the left and right sides of an individual were presumed to be genetically identical, deviations of symmetry were traditionally attributed to non-genetic effects such as environmental and developmental noise. In this review, we draw attention to other possible sources of variability, especially to somatic mutations and transposons. Mutations are a major source of phenotypic variability and recent genomic data have highlighted somatic mutations as ubiquitous, even in phenotypically normal individuals. We discuss the importance of factors that are responsible for buffering and stabilizing the genome and for maintaining size robustness and quality through elimination of less-fit or damaged cells. However, the important question that arises from these studies is whether this self-correcting capacity and intrinsic organ size controls are sufficient to explain how symmetric structures can reach an identical size and shape. Indeed, recent discoveries in the fruit fly have uncovered a conserved hormone of the insulin/IGF/relaxin family, Dilp8, that is responsible for stabilizing body size and symmetry in the face of growth perturbations. Dilp8 alarm signals periphery growth status to the brain, where it acts on its receptor Lgr3. Loss of Dilp8-Lgr3 signaling renders flies incapable of detecting growth perturbations and thus maintaining a stable size and symmetry. These findings help to understand how size and symmetry of somatic tissues remain undeterred in noisy environments, after injury or illnesses, and in the presence of accumulated somatic mutations.
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- 2018
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137. Post-translational buffering leads to convergent protein expression levels between primates
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Sidney H. Wang, Chiaowen Joyce Hsiao, Zia Khan, and Jonathan K. Pritchard
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Buffering ,Translation ,Ribosome profiling ,Primate evolution ,Gene regulation ,Biology (General) ,QH301-705.5 ,Genetics ,QH426-470 - Abstract
Abstract Background Differences in gene regulation between human and closely related species influence phenotypes that are distinctly human. While gene regulation is a multi-step process, the majority of research concerning divergence in gene regulation among primates has focused on transcription. Results To gain a comprehensive view of gene regulation, we surveyed genome-wide ribosome occupancy, which reflects levels of protein translation, in lymphoblastoid cell lines derived from human, chimpanzee, and rhesus macaque. We further integrated messenger RNA and protein level measurements collected from matching cell lines. We find that, in addition to transcriptional regulation, the major factor determining protein level divergence between human and closely related species is post-translational buffering. Inter-species divergence in transcription is generally propagated to the level of protein translation. In contrast, gene expression divergence is often attenuated post-translationally, potentially mediated through post-translational modifications. Conclusions Results from our analysis indicate that post-translational buffering is a conserved mechanism that led to relaxation of selective constraint on transcript levels in humans.
- Published
- 2018
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138. Pain perception of a new Ahmad‐Humayun solution for local anesthesia in hair transplantation: One step ahead.
- Author
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Mohmand, Mohammad Humayun, Ahmad, Muhammad, and Jabeen, Mussarat
- Subjects
- *
HAIR transplantation , *PAIN perception , *LOCAL anesthesia , *OPERATIVE surgery , *LOCAL anesthetics , *SODIUM bicarbonate - Abstract
Background: Local anesthetic is one of the major ways to obtain satisfactory anesthesia in majority of plastic surgical procedures. Objectives: To compare the effect on pain while injecting buffered vs nonbuffered local anesthetic. Materials and methods: The single‐blind, split‐scalp study was conducted in 25 patients undergoing first hair transplant surgery after informed consent and ethics committee approval using two solutions. Solution A was composed of normal saline (200 mL), 2% lidocaine (40 mL), 1 mL of epinephrine 1:1000, and triamcinolone acetate (40 mg). Solution B was composed of normal saline (200 mL), 2% lidocaine (40 mL), 1 mL of epinephrine 1:1000, triamcinolone acetate (40 mg), and 8.4% soda bicarbonate (5 mL). A 3‐mL syringe with 30‐G needle was used. On one side of the scalp, solution A was used and solution B on the other side. The pain response was recorded using Wong‐Baker Faces Pain Scale corresponding to 0‐10 scale. The data were analyzed statistically. No preoperative analgesic was used in any patient. The injections were administered by the 2nd author. Results: A total of 25 patients were included in the study. The mean age of the patients was 33.4 years (range; 28 to 41 years). The average pain score was 4.96 (range, 3‐7) with solution A whereas 3.28 (range, 2‐6) using the solution B (P <.05). Eleven of the patients (44%) were smokers. The average pain score in smokers was 5.82 with solution A and 3.73 with solution B. The pain score in nonsmokers was 4.29 with solution A and 2.93 with solution B (P <.05). [ABSTRACT FROM AUTHOR]
- Published
- 2021
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- View/download PDF
139. Steel Corrosion in Calcium Aluminate Cement Mortar against Chloride.
- Author
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Ki Yong Ann, Hee Jun Yang, Hansol Kim, Jiseok Kim, Won Jung Cho, and Ho Seop Jung
- Subjects
CALCIUM aluminate ,PORTLAND cement ,CHLORIDES ,CEMENT ,CORROSION resistance - Abstract
Three different types of calcium aluminate cement (CAC) were investigated about their resistance to chloride-induced corrosion of steel. CAC imposed higher corrosion resistance compared with ordinary portland cement (OPC). The corrosion current density in CAC was nearly indicative of the passivity, ranging below 1.0 mA/m2 (6.45 × 10-4 mA/in.2) during the entire duration of monitoring. Some rust was slightly formed on the steel surface in a CAC mixture in the visual examination, while the steel reinforcing bars in OPC were severely corroded along the entire surface, with a corrosion current density up to 56.3 mA/m2 (3.63 × 10-2 mA/in.2). Additionally, chloride transport was delayed in CAC by a reduction in the surface chloride, accounting for 1.34 to 1.84% by weight of the binder. The chloride binding capacity of CAC was lower but buffering against a pH fall was higher to keep bound chlorides unreactive in the CAC matrix to enhance the corrosion resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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140. Bargain Hunting for Buffered Lidocaine: A Collaborative Discovery of Cost-saving Strategies That Can Improve Patient Care.
- Author
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Simmons, Curtis L., Harper, Laura K., Holst, Kathryn J., Brinkman, Nathan J., and Lee, Christine U.
- Subjects
LIDOCAINE ,ANESTHETICS ,SODIUM bicarbonate ,COST control ,PHARMACY - Abstract
Buffered lidocaine is a local anesthetic option during percutaneous needle-directed procedures in the breast. At our institution, sodium bicarbonate (the buffer) is dispensed in volumes that frequently lead to medical waste and shortages. In this study, we describe how moving the buffering of lidocaine from the procedure room to our clinical hospital pharmacy results in a reduction in costs and improves satisfaction across the breast radiology department. While cost savings are difficult to tease out in practices that opt for bundled payments, we were able to access pricing and supply data and coordinate with our pharmacy to change our practice. Making these changes saves our practice $26 000 a year and allows us to continue to offer buffered lidocaine even during sodium bicarbonate shortages. This manuscript describes how these changes came about and their economic impact. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
141. A periodic optimization approach to dynamic pickup and delivery problems with time windows.
- Author
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Karami, Farzaneh, Vancroonenburg, Wim, and Vanden Berghe, Greet
- Subjects
MIXED integer linear programming - Abstract
In dynamic pickup and delivery problems with time windows (PDPTWs), potentially urgent request information is released over time. This gradual data availability means the decision-making process must be continuously repeated. These decisions are therefore likely to deteriorate in quality as new information becomes available. It is still believed that the state of the art for this problem remains far from reaching maturity due to the distinct absence of algorithms and tools for obtaining high-quality solutions within reasonable computational runtimes. This paper proposes a periodic approach to the dynamic PDPTW based on buffering, more specifically a two-step scheduling heuristic which consists of the cheapest insertion followed by a local search. The heuristic's performance is assessed by comparing its results against those obtained by a mixed integer linear programming model which operates under the assumption that all information is available in advance. Results illustrate how the performance is impacted by urgency levels, the degree of dynamism associated with request arrivals and re-optimization frequency. The findings indicate that increases in dynamism improve solution quality, whereas increases in urgency have the opposite effect. In addition, the proposed approach's performance is only slightly affected by re-optimization frequency when changing these two characteristics. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
142. Post‐adoption buffering effects of innovative product aesthetics.
- Author
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Nagel, Christian and Schumann, Jan H.
- Subjects
DIFFUSION of innovations ,AESTHETICS ,ATTITUDE (Psychology) - Abstract
Innovative aesthetic product appearances can create buffering effects in the pre‐adoption phase that lead consumers to base their expectations on the aesthetics rather than on objective information about innovative products. How do innovative aesthetics influence product experience in the post‐adoption phase? Using longitudinal post‐adoption data from early adopters of an electric car model, this study shows that consumers' perceptions of innovative aesthetic value buffer the effect of product‐related hedonic experience on attitudes towards the product. The more value consumers derive from innovative product aesthetics post‐adoption, the less they ground their attitudes on actual hedonic experience. Product managers thus should opt for designs that grant aesthetic utility over time. Innate consumer innovativeness levels moderate the buffering effect, such that the effect of aesthetic innovative product evaluations on the relationship between experienced hedonic utility and attitude is stronger for more innovative consumers. Innovative consumers are especially sensitive to innovative aesthetic value, so in their co‐creation efforts, managers should seek out these customers, because doing so can increase early adopters' long‐term product satisfaction and word of mouth, both of which expand the breadth of diffusion for the innovations. [ABSTRACT FROM AUTHOR]
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- 2020
- Full Text
- View/download PDF
143. High-Accuracy Packet Pacing on Commodity Servers for Constant-Rate Flows.
- Author
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Hawari, Mohammed, Cordero-Fuertes, Juan-Antonio, and Clausen, Thomas
- Subjects
COMMERCIAL products ,MEDIA consumption ,STREAMING media - Abstract
This paper addresses the problem of high-quality packet pacing for constant-rate packet consumption systems, with strict buffering limitations. A mostly-software pacing architecture is developed, which has minimal hardware requirements, satisfied by commodity servers – rendering the proposed solution easily deployable in existing (data-centre) infrastructures. Two algorithms (free-running and frequency-controlled pacing, for explicitly and implicitly indicated target rates, respectively) are specified, and formally analysed. The proposed solution, including both algorithms, is implemented, and is tested on real hardware and under real conditions. The performance of these implementations is experimentally evaluated and compared to existing mechanisms, available in general-purpose hardware. Results of both exhaustive experiments, and of an analytical modeling, indicate that the proposed approach is able to perform low-jitter packet pacing on commodity hardware, being thus suitable for constant rate transmission and consumption in media production scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
144. Ocean Alkalinity, Buffering and Biogeochemical Processes.
- Author
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Middelburg, Jack J., Soetaert, Karline, and Hagens, Mathilde
- Abstract
Alkalinity, the excess of proton acceptors over donors, plays a major role in ocean chemistry, in buffering and in calcium carbonate precipitation and dissolution. Understanding alkalinity dynamics is pivotal to quantify ocean carbon dioxide uptake during times of global change. Here we review ocean alkalinity and its role in ocean buffering as well as the biogeochemical processes governing alkalinity and pH in the ocean. We show that it is important to distinguish between measurable titration alkalinity and charge balance alkalinity that is used to quantify calcification and carbonate dissolution and needed to understand the impact of biogeochemical processes on components of the carbon dioxide system. A general treatment of ocean buffering and quantification via sensitivity factors is presented and used to link existing buffer and sensitivity factors. The impact of individual biogeochemical processes on ocean alkalinity and pH is discussed and quantified using these sensitivity factors. Processes governing ocean alkalinity on longer time scales such as carbonate compensation, (reversed) silicate weathering, and anaerobic mineralization are discussed and used to derive a close‐to‐balance ocean alkalinity budget for the modern ocean.Plain Language Summary: The ocean plays a major role in the global carbon cycle and the storage of anthropogenic carbon dioxide. This key function of the ocean is related to the reaction of dissolved carbon dioxide with water to form bicarbonate (and minor quantities of carbonic acid and carbonate). Alkalinity, the excess of bases, governs the efficiency at which this occurs and provides buffering capacity toward acidification. Here we discuss ocean alkalinity, buffering, and biogeochemical processes and provide quantitative tools that may help to better understand the role of the ocean in carbon cycling during times of global change.Key Points: Titration and charge balance alkalinity differThe impact of biogeochemical processes on pH depends on environmental conditionsOcean alkalinity budget is balanced when the additional alkalinity input from riverine particulate inorganic carbon and sedimentary sources is included [ABSTRACT FROM AUTHOR]
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- 2020
- Full Text
- View/download PDF
145. ПРОУЧВАНЕ СЪДЪРЖАНИЕТО И РАЗПРЕДЕЛЕНИЕТО НА АКТИВЕН КАЛЦИЙ ПО ПОЧВЕНИЯ ПРОФИЛ НА БЕЗКАРБОНАТНИ ПОЧВИ В КАЗАНЛЪШКАТА КОТЛОВИНА
- Author
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Алмалиев, Младен
- Abstract
The content and the forms of calcium association in the soils is a complex characteristic of the plant nutrient regimes, soil buffering, condition and capacity of the sorption complex, the degree of development of the soil profile and some economic characteristics related to the general functionality and suitability of the soil for agriculture. Each of these calcium conditions in the soil is established by different research methods, and they in turn are associated with models of interpretation of the role of Ca in the respective aspect - genesis and development of the soil profile, physic-chemical characteristics of acid-alkaline balance, condition and stability of the organicmineral absorption complex, conditions of mineral nutrition of the plants, etc. In a large part of the studied genetically acid soils it was found that the structure of harmful soil acidity was based on increased levels of easily mobile aluminum, hydrogen and manganese, as well as a strong reduction in the levels of the easily mobile exchangeable bases. In order to neutralize the harmful acidity and to cover the cost levels in the calcium balance and ultimately to increase the yield, a balance rate must be calculated, leading not to complete neutralization of the constant sorption positions, but to reduction of the toxic action of mobile aluminum, hydrogen and manganese. [ABSTRACT FROM AUTHOR]
- Published
- 2020
146. The Muscle Carnosine Response to Beta-Alanine Supplementation: A Systematic Review With Bayesian Individual and Aggregate Data E-Max Model and Meta-Analysis.
- Author
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Rezende, Nathália Saffioti, Swinton, Paul, de Oliveira, Luana Farias, da Silva, Rafael Pires, da Eira Silva, Vinicius, Nemezio, Kleiner, Yamaguchi, Guilherme, Artioli, Guilherme Giannini, Gualano, Bruno, Saunders, Bryan, and Dolan, Eimear
- Subjects
CARNOSINE ,META-analysis ,DATA modeling ,MUSCLES ,SKELETAL muscle - Abstract
Beta-alanine (BA) supplementation increases muscle carnosine content (MCarn), and has many proven, and purported, ergogenic, and therapeutic benefits. Currently, many questions on the nature of the MCarn response to supplementation are open, and the response to these has considerable potential to enhance the efficacy and application of this supplementation strategy. To address these questions, we conducted a systematic review with Bayesian-based meta-analysis of all published aggregate data using a dose response (Emax) model. Meta-regression was used to consider the influence of potential moderators (including dose, sex, age, baseline MCarn, and analysis method used) on the primary outcome. The protocol was designed according to PRISMA guidelines and a three-step screening strategy was undertaken to identify studies that measured the MCarn response to BA supplementation. Additionally, we conducted an original analysis of all available individual data on the MCarn response to BA supplementation from studies conducted within our lab (n = 99). The Emax model indicated that human skeletal muscle has large capacity for non-linear MCarn accumulation, and that commonly used BA supplementation protocols may not come close to saturating muscle carnosine content. Neither baseline values, nor sex, appeared to influence subsequent response to supplementation. Analysis of individual data indicated that MCarn is relatively stable in the absence of intervention, and effectually all participants respond to BA supplementation (99.3% response [95%CrI: 96.2–100]). [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
147. The role of incubator support in new firms accumulation of resources and capabilities.
- Author
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Breivik-Meyer, Marit, Arntzen-Nordqvist, Marianne, and Alsos, Gry Agnete
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BUSINESS incubators ,INCUBATORS ,BUSINESS enterprises ,SOCIAL networks ,COMPETITIVE advantage in business - Abstract
Entrepreneurs need to accumulate different types of resources and capabilities to gain a competitive advantage for their firms, often in settings characterised by uncertainty and complexity. The purpose of business incubators is to provide new firms with a structured and nurturing environment during the early development stages and thus help firms accumulate the necessary capabilities and resources for development and growth. Drawing from an organizational sponsorship framework, this study examines the role of incubator support, referred to as buffering and bridging mechanisms, in the accumulation of capabilities and external resources in new firms. We conceptualise two types of buffering mechanisms in the context of business incubation: sheltering and building. Acknowledging that incubator services may differ in their influence on firm development, and that such influence depends on the extent to which the firms actually utilise the provided services, this study analyses firms' use of various incubator services, and its effect on their accumulation of resources and capabilities. Analyses of data collected from 253 tenant firms of business incubators in Norway suggest that the bridging mechanism (i.e., external network support) and the sheltering mechanism provided by incubator management are important for firms to acquire external resources (i.e., financing, new customers) and to develop capabilities (i.e., organisational processes and routines). This study highlights the importance of different incubator support mechanisms for the resource and capability accumulation of new firms. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
148. Biochemical composition and quality of herring preserves with addition of bio-protective cultures.
- Author
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Bazarnova, J., Korableva, N., Ozerova, O., and Moskvicheva, E.
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UNSATURATED fatty acids , *OMEGA-3 fatty acids , *ATLANTIC herring , *FISH spoilage , *DOCOSAHEXAENOIC acid , *TRYPTOPHAN - Abstract
Herrings rich in vitamins B12, A, D, minerals, including calcium, potassium, magnesium, iodine, possess high levels of lysine, tyrosine, phenylalanine and tryptophan, as well as omega-3 unsaturated fatty acids, namely eicosapentanoic, docosahexoenoic and docosapentoenoic. To suppress the microbiological spoilage of fish preserves, it is promising to use bio-protective cultures that have minimal impact on the production process and product properties. Bacterial strains are able to exert a static effect on the microflora, which causes biodeterioration of food products. Microorganisms as part of bio-protective cultures are included in the fermentation process, so they can be attributed to ordinary food ingredients, so there is no need to put separate information on the packaging. The chemical composition of the frozen Atlantic and Pacific herring fillet, the amino acid composition of proteins, and the fatty acid composition of lipids were studied. The difference between Atlantic and Pacific herrings was detected, which consists in a significantly higher content of docosahexaenoic acid. The difference in the fractional composition of triacylglycerols for the Atlantic and Pacific herring was established. The microflora of SafePro B-2 biological product (Chr. Hansen GmbH), containing multiple strains of Lactobacillus sakei, and the viability of the culture in preserves fillings were studied. The experimental development of canned food with SafePro B-2 additives was carried out. Microbiological, organoleptic and biochemical indicators of the preserves quality during cold storage were studied. The influence of introduced culture on the dynamics of preserves curing period and their shelf life was established. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
149. The influence of progressive-chronic and acute sodium bicarbonate supplementation on anaerobic power and specific performance in team sports: a randomized, double-blind, placebo-controlled crossover study.
- Author
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Durkalec-Michalski, Krzysztof, Nowaczyk, Paulina M., Adrian, Jacek, Kamińska, Joanna, and Podgórski, Tomasz
- Subjects
SPORTS nutrition ,ATHLETIC ability ,HOCKEY ,STATISTICAL sampling ,SODIUM bicarbonate ,SPORTS medicine ,ANAEROBIC threshold ,RANDOMIZED controlled trials ,DESCRIPTIVE statistics - Abstract
Background: The aims of this study were to verify the effect of progressive-chronic and acute sodium bicarbonate (SB) supplementation on the anaerobic capacity, blood acid-base balance, and discipline-specific performance in team sports disciplines. Methods: Twenty-four trained male field hockey players completed a randomized, placebo-controlled, crossover trial of either progressive-chronic (increments from 0.05 up to 0.2 g/kg) or an acute one-off dose (0.2 g/kg) supplementation protocol. Before and after treatments, athletes completed an exercise protocol that comprised of a discipline-specific field performance test conducted between two separate Wingate anaerobic tests (WAnTs). Results: Progressive-chronic SB supplementation improved anaerobic capacity in the first bout of WAnTs, as observed based on an increase in mean power (MP: 575 ± 71 vs. 602 ± 67 W, p = 0.005, ~ + 4.7%), peak power (PP: 749 ± 94 vs. 777 ± 96 W, p = 0.002, ~ + 3.7%), power carry threshold (P
CT ) at 97%PP (727 ± 91 vs. 753 ± 93 W, p = 0.002, ~ + 3.6%) and average power over PCT (739 ± 94 vs. 765 ± 95 W, p = 0.001, ~ + 3.5%). Acute SB supplementation had no effect on anaerobic capacity. However, an improvement in time during discipline-specific field performance test was observed after progressive-chronic (919 ± 42 vs. 912 ± 27 s, p = 0.05; ~ − 0.8%) and acute (939 ± 26 vs. 914 ± 22 s, p = 0.006, ~ 2.7%) SB supplementation. Acute SB supplementation also improved post-exercise parameters of acid-base balance (based on blood pH, bicarbonate concentration and base excess) compared to no supplementation or placebo. Conclusions: Our study indicates that both chronic and acute SB supplementation positively supports discipline-specific performance among field hockey athletes. Moreover, the chronic protocol supported anaerobic power indices before the inset of exercise-induced fatigue but had no significant impact afterwards. However, only the acute protocol significantly affected the buffering capacity, which can be used to determine athlete's performance during high-intensity sporting events. This study design therefore highlighted that future studies focusing on sodium bicarbonate supplementation in team sports should concentrate on the efficiency of chronic and acute supplementation in varying time frames. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
150. Integrative Omics Analysis Reveals a Limited Transcriptional Shock After Yeast Interspecies Hybridization.
- Author
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Hovhannisyan, Hrant, Saus, Ester, Ksiezopolska, Ewa, Hinks Roberts, Alex J., Louis, Edward J., and Gabaldón, Toni
- Subjects
PLANT hybridization ,SACCHAROMYCES ,SPECIES hybridization ,YEAST ,THERMAL shock ,GENE expression ,NUCLEOTIDE sequence - Abstract
The formation of interspecific hybrids results in the coexistence of two diverged genomes within the same nucleus. It has been hypothesized that negative epistatic interactions and regulatory interferences between the two sub-genomes may elicit a so-called genomic shock involving, among other alterations, broad transcriptional changes. To assess the magnitude of this shock in hybrid yeasts, we investigated the transcriptomic differences between a newly formed Saccharomyces cerevisiae × Saccharomyces uvarum diploid hybrid and its diploid parentals, which diverged ∼20 mya. RNA sequencing (RNA-Seq) based allele-specific expression (ASE) analysis indicated that gene expression changes in the hybrid genome are limited, with only ∼1–2% of genes significantly altering their expression with respect to a non-hybrid context. In comparison, a thermal shock altered six times more genes. Furthermore, differences in the expression between orthologous genes in the two parental species tended to be diminished for the corresponding homeologous genes in the hybrid. Finally, and consistent with the RNA-Seq results, we show a limited impact of hybridization on chromatin accessibility patterns, as assessed with assay for transposase-accessible chromatin using sequencing (ATAC-Seq). Overall, our results suggest a limited genomic shock in a newly formed yeast hybrid, which may explain the high frequency of successful hybridization in these organisms. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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