Research data indicates a persistence of elevated muscle glycogen concentration 3 days post-supercompensation in resting athletes. This study expands our earlier findings by determining whether muscle glycogen remains elevated 3, 5, or 7 days post-supercompensation. Seventeen trained male cyclists underwent one bout of exhaustive exercise to deplete muscle glycogen. This was followed by a 3-day consumption of a high carbohydrate/low protein/low fat diet (85:08:07%). Three post-loading phases followed with subjects randomly assigned to either a 3-day, 5-day, or 7-day post-loading maintenance diet of 60% carbohydrate and limited physical activity. Biopsies (50-150 mg) of the vastus lateralis were obtained pre-load (BASELINE), at peak-load (PEAK), and either at 3-day, 5-day, or 7-day post-load (POST). On average, PEAK to POST muscle glycogen concentrations decreased 34, 20 and 46% respectively for the 3-, 5-, and 7-day POST groups. Only the 7-day post-load group's PEAK to POST mean muscle glycogen concentration decreased significantly. In addition, multi-regression analysis indicated that the PEAK glycogen level was the main determinant of the number of days that glycogen levels remained significantly greater than BASELINE. Thus, trained athletes-supercompensated glycogen levels can remain higher than normal for up to 5 days post-loading. The amount of carbohydrate consumed, the level of physical activity, and the magnitude of the glycogen supercompensation determine the interval for which the glycogen levels are elevated.

Geogrid reinforcement can improve the performance of pavements by stiffening the aggregate base material and decreasing pavement deformations. Understanding the effects of cyclic loading on the modulus of geogrid-reinforced base materials would help engineers better anticipate actual increases in the modulus of aggregate base materials under given traffic loads. The objective of this laboratory research was to investigate the effects of cyclic loading on the resilient modulus, the modulus to peak axial stress, the elastic modulus, and the modulus at 2 percent strain of geogrid-reinforced aggregate base materials. The scope of the research included two aggregate base materials (Wells Draw and Springville) having different particle-size distributions and particle angularity. Geogrid-reinforced and unreinforced specimens were subjected to conditioning periods consisting of cyclic loading ranging from 10 to 10,000 cycles. Immediately following cyclic loading, all specimens were tested using the quick shear portion of the American Association of State Highway and Transportation Officials T 307 (Determining the Resilient Modulus of Soils and Aggregate Materials). Specimen preparation involved material weigh-outs, compaction, and membrane applications. Specimen testing in the loading machine consisted of two testing portions, including cyclic loading and quick shear testing. The cyclic loading data were used to calculate the resilient modulus on 200-cycle intervals throughout the duration of the conditioning period. The quick shear data were used to calculate the peak axial stress, the modulus to peak axial stress, the elastic modulus and the modulus at 2 percent strain. For the Wells Draw material, the resilient modulus increases by 11 percent for the specimens with geogrid and increases by 8 percent for the specimens without geogrid as the number of load cycles increases from 1,000 to 10,000. For the Springville material, the resilient modulus increases by 2 percent for the specimens with geogrid and increases by 3 percent for the specimens without geogrid as the number of load cycles increases from 1,000 to 10,000. As with other studies, the results do not show a consistent or significant effect of geogrid reinforcement on the resilient modulus of the tested materials. The modulus at 2 percent strain has the most potential for consistently showing improvements to aggregate base materials due to both cyclic loading and geogrid reinforcement. For the Wells Draw and Springville materials, the modulus at 2 percent strain increases by 31 and 9 percent, respectively, as the number of load cycles increases from 10 to 10,000. Additionally, for the Wells Draw and Springville materials, the modulus at 2 percent strain of the specimens with geogrid is 23 and 46 percent, respectively, greater than that of the specimens without geogrid. The results show a consistent and significant positive effect of geogrid reinforcement on modulus at 2 percent strain of the tested materials. According to the modulus at 2 percent strain results, a sufficient conditioning period appears to occur at 5,000 cycles for the Wells Draw material and 10,000 cycles for the Springville material.

Aims: The peak transmitral velocity/peak mitral annular velocity (E/e′) ratio has been used as a left ventricular (LV) filling pressure (LVFP) correlate. However, the E/e′ and its changes with haemodynamic alterations have not always correlated with changes in LVFP's. We hypothesized that indexing E/e′ to a measure of LV filling volume may enhance the correlation with LVFP and LVFP changes. Methods and results: We summarized previously obtained haemodynamic and Doppler echo data in 137 dogs with coronary microsphere embolization induced-chronic LV dysfunction prior to and following haemodynamic induced alterations in LVFP's. E/e′ values were obtained as E∗tau where tau is the inverse logarithmic LV pressure decay. E∗tau was indexed to LV filling volume by dividing by the diastolic time velocity integral (DVI) and correlated with LV mean diastolic pressure (LVmDP). Similarly, the relationship of E/e′ and E/e′/DVI to LV pre A wave pressure was evaluated in 84 patients by invasive haemodynamics and Doppler echo. Combining data from all interventions, LVmDP correlated with E∗tau (r = 0.408) but more strongly with E∗tau/DVI (r = 0.667, z = 3.03, P = 0.0008). The change in LVmDP correlated with the change in E∗tau/DVI (r = 0.742) more strongly than E∗Tau (r = 0.187, Z = 4.01, P < 0.0001). In the patient cohort, E/e′ was modestly correlated with LV pre A wave pressure (r = 0.301) but more strongly correlated with E/e′/DVI (r = 0.636, z = 2.36, P = 0.0161). Conclusion: Indexing E to both LV relaxation and filling volume results in a more robust relation with LVFP's and with LVFP changes.

Dynamic Visual Acuity (DVA) in the visual periphery has not been extensively studied. DVA is a measure of an observer's ability to resolve critical details in a target when there is relative motion between the target and the observer. This dissertation examined static and dynamic acuity in the 25-55 deg region of retinal eccentricity under a variety of conditions. Functionally, this region of the visual field is just beyond the "blind spot," but not yet in the "far" visual periphery of 60-90 deg of eccentricity. Traditionally, DVA research has been confined to the assessment of DVA for the foveal (or "central") visual system. However, the peripheral (or "ambient") visual system provides very important information content for the visual and neuro-vestibular systems. This peripheral visual information content is also used to create a sense of ego motion (termed "vection"), and for alerting the visual system to targets entering or leaving the field of view. Past findings involving visual acuity in the peripheral retina have demonstrated that peripheral acuity performance has components related to the notion of "attention" as well. This is particularly true if the peripheral vision research results are to be applied to visually and attentionally complex and/or dynamic real-world environments. In this experiment, the 25-55 deg eccentric region of the retina was tested for DVA in 50 observers. This study used a mixed four-factor research design with Eccentricity (25, 35, 45, 50, 55 deg) as a between-subjects factor. Tracking Difficulty (monitor only, easiest, moderate, most difficult tracking levels), Landolt C Target Velocities (0.0, 4.88, 14.62, and 24.40 deg/s), and Target Direction ("F/R:" fixed or random direction of target appearance) were used as within-subjects factors. A computer presented the Landolt C ring targets under the stated conditions in a random fashion. Acuity was determined for each trial by a modified descending method-of-limits approach with the Landolt C ring target gap widths utilized as the determinant for the acuity measure. The Tracking Task was designated as the primary task, with the secondary task being to indirectly observe the orientation (up, down, right, left) of the Landolt C rings being presented under the various conditions of Target Velocity and Target Direction in the retinal periphery. The resulting Analysis of Variance (ANOVA) revealed significant differences (p < 0.05) for each of the main effects of Eccentricity, Tracking Task Difficulty, Velocity, and Target Direction (F/R). Only two of the two-way interactions were found to be significant (p < 0.05)-- those of Tracking Difficulty x Target Velocity and Target Velocity x Target Direction interactions. The results are discussed in terms of the psychophysical, attention, and "tunnel vision" like models of peripheral visual performance, along with other related human factors literature in the domain of "situation awareness" that are relevant to this general problem area. The results of a separate follow-on mini-study are discussed using a Two-way Contingency Table analysis across all of the treatment conditions when verbal intrusion was embedded in the previously described experimental conditions. This mini-study revealed a significant association (p < 0.05) with not seeing the peripheral targets as accurately when intrusion was present, versus when there was no verbal intrusion. This effect was more pronounced at the highest velocities (14.62 and 24.40 deg/s) as compared with the slower ones (0 and 4.88 deg/s) in terms of the strength of the association, as assessed by a Kappa test statistic. Taken all together, and with consideration given to the relatable scientific literature, these results indicate that the more "busy" a person is with cognitive, visual, or motor-skills tasks, the more likely an individual will show degradation in static or dynamic peripheral visual acuity tasks. Peripheral vision often serves as a "warning" or "status" sensory modality for what is occurring in the local task environment, separate from the foveal visual system. Future research is suggested given the sensitivity of the peripheral visual system to these factors, particularly with regard to how factors involving the notion of attention may affect such "peripheral visual awareness" issues. These issues in turn may play an important role from a human factors and safety perspective in a variety of person-rated vehicular domains. Specific areas that are highlighted for future research in the domain of attention and "peripheral visual awareness" include the low-altitude high-performance flying realm, the flying environment more generally, and in other dynamic multi-task vehicular environments such as that encountered while simultaneously driving and using a car cellular phone. / Ph. D.

Metal-plate-connected (MPC) splice joints were tested in combined tension and bending to generate data that were used in the development of a design procedure for determining the steel net-section strength of bottom chord splice joints of MPC wood trusses. Several common wood truss splice joint configurations were tested at varying levels of combined tension and bending loading. The joint configurations were 2x4 lumber with 20-gauge truss plates, 2x6 lumber with 20-gauge truss plates, and 2x6 lumber with 16-gauge truss plates. All the joints tested failed in the steel net-section of the truss plates. The combined loading was achieved by applying an eccentric axial tension load to the ends of each splice joint specimen. Three structural models were developed to predict the ultimate strength of the steel net-section of the splice joints tested under combined tension and bending loading. The test data were fitted to each model, and the most accurate model was selected. Data from other published tests of splice joints were used to validate the accuracy of the selected model. A design procedure for determining the allowable design strength of the steel net-section of a splice joint subjected to combined tension and bending was developed based on the selected model. The new design procedure was compared with two existing design methods. The proposed design procedure is recommended for checking the safe capacity of the steel net-section of bottom chord splice joints of MPC wood trusses subjected to combined tension and bending. / Master of Science

Lake Manassas is an approximate 706 acre man-made lake located in greater Prince William County near the town of Gainesville, Virginia. The lake was created in 1968 on Broad Run to serve as the primary water supply for the City of Manassas and its residents. The Lake Manassas watershed lies within the greater Occoquan River watershed which drains into the Potomac River and Chesapeake Bay. Water within Lake Manassas and its tributaries has been monitored since 1971 and this thesis presents a comprehensive limnological analysis of the Lake with an analysis of water quality impacts over time. Lake Manassas remains an enriched or eutrophic system, meaning the levels of nutrients and biomass production in lake waters is above desired standards. Nutrient loading occurs via a stream network with the largest contributor being Broad Run which is consistent with previous water quality studies. The lake serves as the sole water source for nearly 40,000 residents and businesses and ensuring clean and safe water is of significant importance. Close monitoring in conjunction with the implementation of appropriate management practices within the watershed are necessary to prevent water quality from becoming significantly degraded. / Master of Science

Indiana University-Purdue University Indianapolis (IUPUI) / Phosphorus (P) is essential for aquatic life; cycling between both inorganic and organic forms to maintain an ecological balance. Its addition into P-scarce freshwaters, either through terrestrial (external) or sedimentary (internal) loading, may disrupt this balance causing blooms of phytoplankton to flourish, often resulting in harmful environmental and anthropogenic consequences. Accordingly, reduction of external P loading has been commonly implemented with a recent focus on sediment-bound legacy P that is mobilized into the water column during dynamic redox conditions. Mobile P species have been identified as both inorganic and organic, with the former representing the most bioavailable fraction, and the latter serving as a source for labile P in freshwaters when in high demand, particularly during blooms. Missisquoi Bay in Lake Champlain, VT experiences harmful cyanobacterial blooms driven by internal P loading and has been the target of numerous geochemical and hydrological studies. This thesis describes a high-resolution investigation of both the organic P and organic matter compositions of the bay with respect to mobility, reactivity, and bioavailability using Fourier Transform-Ion Cyclotron Mass Spectrometry (FT-ICR MS). Sediment from Missisquoi Bay was extracted with a diverse set of reagents, resulting in fractionation of both organic matter and organic P, and illustrating the distribution of various labile and recalcitrant compounds. Many of these molecules are associated with porewater or easily extractable mineral surfaces providing a link to the benthic organic matter and phosphorus fractions available to microorganisms. Additionally, the organic chemistry of the bay was investigated seasonally from May 2017 to January 2018 revealing biological processing from the spring runoff season through the post-bloom summer season. The transition from late summer to under ice conditions in winter was less severe with a higher commonality between both organic matter and organic P compounds, suggesting reduced biological and abiotic degradation. Moreover, short-term anoxic incubations of sediment cores from each season revealed the presence of diverse organic signatures from sorption processes, and a significant contribution of benthic microbial activity to the benthic organic geochemistry.

Ökad folkmängd och infrastruktur skapar alltmer behov av godstransport. Godstransporter är en väsentlig del av samhällsutvecklingen och kommer alltid att vara. Men tyvärr medför det negativa belastningar på miljön. Dock finns det teorier som säger att det finns samband mellan fyllnadsgraden och antalet lastbilar. Att effektivisera fyllnadsgraden är att minska antalet lastbilar som eventuellt leder till mindre miljöbelastningar. Syftet med studien är att undersöka korrelationen mellan lastbilstrafiken och dess fyllnadsgrad. Vidare är syftet att föreslå en lösning till att optimera fyllnadsgraden för lastbilar. För att få ett omfattande perspektiv kring problematiken och föreslå ett tillämpbart koncept inom projektets ramar, avgränsas studien till godstransportsektorn i Göteborg. Motiveringen till den geografiska avgränsningen är med hänsyn till Göteborgs vision att bli Nordens logistikcentrum 2035 (Trafikkontoret, 2014). Projektet är därav begränsat ytterligare till lastbilar som står för ca 30 procent av växthusgasutsläppen (Naturvårdsverket, 2020). Statistiken från trafikanalys om lastbilar (Trafikanalys, 2021) blev grunden till konstaterandet att fyllnadsgraden inte utnyttjas fullt och därför behöver effektiviseras. Den kvalitativa metoden “semistrukturerad intervju” hölls med Trafikkontoret och några aktörer inom transportsektorn, vilka kom att bli Derome och Bring, för att ytterligare kartlägga var exakt i värdeflödet bristen ligger. Projektets frågeställningar är konstruerade utefter samhällets behov och dagens bekymmer som även kan påverka framtida generationer. Underlag till projektets resultat är kvalitativ och kvantitativ insamlad data. Resultatet av studien visade sig att dålig fyllnadsgrad, samt frekventa tomkörningar av lastbilar ökar transportsträckorna som leder till miljöbelastning. En lösning är att optimera fyllnadsgraden och minska tomkörningar hos lastbilstransport, vilket görs genom samlastning som denna studie föreslår. Samlastning (Figur 3) minskar lastbilarnas transportsträckor och effektiviserar godstransporters värdeflöde. Konceptet leder till mindre buller, emissioner, skadliga partiklar, slitage och trafikering, utan att ha en negativ påverkan på näringslivet. Studien är generell och riktar sig till alla berörda aktörer och myndigheter som berörs av transportbranschen, speciellt lastbilstransporter, och som ett underlag till deras uppsatta miljömål och en potentiell strategi för en hållbar transport. / The increasing population and infrastructure development creates need for more demands and supplies, which eventually leads to increase in transport movements. Freight transport have become an essential part of the rapidly growing communities, but unfortunately entails the negative impact on environment as well. The purpose of this project is to find the correlation between fright transport and its loading factor. Furthermore, the purpose is to suggest a solution for optimizing the loading factor in fright transport. In order to gain a comprehensive perspective on the subject and suggest an applicable solution within the projects framework, this project is limited to optimization of freight transport sector in Gothenburg. The motivation for the geographical delimitation is, regarding to Gothenburg's vision to become the Nordic logistics center 2035 (Trafikkontoret, 2014). This project is further limited to transport by road, which often are trucks. The motivation for this delimitation is, transport by roads being responsible for almost 30 percent of greenhouse gas emissions (Naturvårdsverket, 2020). The statistical data from “Trafikanalys” on trucks (Trafikanalys, 2021) is the basis for stating that loading factor in freight transport is not efficient and needs to improve. Interviews were held with the Swedish transport agency “Trafikkontoret” and other suppliers in the transport branch to further map where exactly in the value chain lies the shortcomings. The project's issues are constructed according to society's needs and current concerns that may also affect future generations and the basis for the project's results are the qualitative and quantitative data collected. This project's issues are constructed according to society's needs and current concerns that may also affect future generations and the basis for the project's results are the qualitative and quantitative data collected. The result of this study shows that poor utilization of truck´s capacity and frequent empty rides of trucks increase the quantity of transports by trucks which eventually leads to negative environmental impacts. A solution is improving the capacity utilization and reducing empty rides of transports by trucks which could be achieved by co-loading that this project suggests. Co-loading (Figure 3) Improves capacity utilization and improves the value chain of freight transport which eventually leads to less noise, less emissions, less production of harmful particles from trucks, less traffic caused by trucks etc. without having a negative impact on the efficiency. This report in general, is aimed to aid all relevant suppliers and authorities in the transport industry and can be used as a basis for their set environmental policies and potential strategy towards sustainability.

No description available.

Detonation of an explosive charge, such as a mine or an improvised explosive device (IED) at the ground surface or buried at shallow depth in soil, can produce high airblast pressures and significant dynamic soil debris loads on an overlying or nearby structure, such as a vehicle passing over the explosive. The blast loading environment is a function of many factors including the explosive type, configuration, mass, and depth of burial, soil characteristics, and the distance between the ground surface and the structure or object. During the past several years, the US Army has focused considerable attention on developing improved methods for predicting this environment, particularly for use by vehicle/armor analysts, thereby, improving the survivability of these platforms. Research is needed to better understand the aboveground environment created by the detonation of a shallow-buried explosive in order to design adequate protective measures for an aboveground structure. Unfortunately, there is no accurate methodology for predicting these airblast and soil debris loads to support the designs. Development of the required prediction tools is hampered by lack of well controlled and documented experimental results for these complex loads. Without detailed experimental data, the numerical simulations of these loads cannot be adequately validated for the large deformation, stress, and motion gradients and the resulting interactions with structures. The focus of this research is to quantify the influence of soil properties on the aboveground environment from the detonation of a bare explosive charge resting on the soil surface or shallow-buried. In order to fully quantify the influence of soil parameters, well-controlled experiments were designed to directly measure soil debris and airblast loadings on an aboveground reaction structure due to the detonation of explosives at the surface of and shallow buried in three very different soils. The experiments were performed using specifications and strict quality controls that limited the influence of outside variables and ensured the experiments were repeatable. The experiments provided blast pressure, soil stress, and impulse data for each soil type. These data were analyzed to investigate the influence of the properties of the different soil types on the aboveground environment.