This study is an evaluation of epoxy coated reinforcing steel (ECR) and its ability to effectively provide corrosion protection in reinforced concrete highway bridge decks. An analysis was conducted on 10 bridge decks built in the state of Virginia between the years 1981 and 1995. A total of 141 cores containing either ECR or bare steel were evaluated. A chloride solution was applied to the surface on a weekly cycle (for a total duration of 3.06 years) and a nondestructive electrochemical testing was performed on each core on a monthly cycle. Cores were also inspected for surface cracks, the thermal properties of the epoxy coating, and the concrete conditions at bar depth. The concrete was tested for saturation percentages, diffusion coefficients, and chloride contents, while the epoxy was tested for its glass transition temperature, moisture content, and amount of surface cracking. The results indicate that the best predictor for estimating the times to corrosion initiation and cracking is the amount of chlorides present in the concrete encasing the ECR. The presence of chloride ions will have a determining effect on corrosion regardless of the epoxy coating condition. As a result, it is likely that ECR is not the solution to corrosion prevention and it is recommended that closer attention be given to improving concrete conditions that reduce the diffusion of chloride ions. The conclusion that ECR is an unreliable corrosion prevention method is in agreement with the results of previous studies. / Master of Science

Corrosion of reinforcing steel in concrete exposed to chloride-laden environments is a well-known and documented phenomenon. The need for cost effective systems for protection against corrosion has become increasingly clear since the first observations of severe corrosion damage to interstate bridges in the 1960's. As one potential solution to the mounting problem of corrosion deterioration of structures, corrosion-inhibiting admixtures have been researched and introduced into service. This report conveys the results of a three-part laboratory study of corrosion inhibiting admixtures in concrete. The commercial corrosion inhibiting admixtures for concrete have been analyzed by three evaluation methods, including: • Conventional concrete corrosion cell prisms under ponding, • Black steel reinforcing bars immersed in simulated concrete pore solutions, • Electrochemical screening tests of special carbon steel specimens in electrochemical corrosion cells containing filtered cement slurry solution. The purposes of the study include: • Determining the influence of a series of commercially available corrosion inhibiting admixtures on general concrete handling, performance and durability properties not related to corrosion. • Determining the effectiveness of corrosion inhibiting admixtures for reduction or prevention of corrosion of reinforcing steel in concrete, relative to untreated systems, under laboratory conditions. • Conducting a short-term pore solution immersion test for inhibitor performance and relating the results to those of the more conventional long-term corrosion monitoring techniques that employ admixtures in reinforced concrete prisms. • Determining whether instantaneous electrochemical techniques can be applied in screening potential inhibitor admixtures. Concrete properties under test included air content, slump, heat of hydration, compressive strength, and electrical indication of chloride permeability. Monitoring of concrete prism specimens included macro-cell corrosion current, mixed-cell corrosion activity as indicated by linear polarization, and ancillary temperature, relative humidity, and chloride concentration documentation. Simulated pore solution specimens were analyzed on the basis of weight loss and surface area corroded as a function of chloride exposure. Electrochemical screening involved polarization resistance of steel in solution. Results include corrosion potential, polarization resistance and corrosion current density. / Master of Science

Yes / This paper investigated the bond strength of eight nanoinclusions reinforced concrete with old concrete through a splitting tensile test. The reinforcing mechanisms of bond due to nanoinclusion was also explored by means of scanning electron microscope and energy dispersive spectrometer. A prediction model for the bond strength between nanoinclusion reinforced concrete with old concrete substrate was developed and calibrated against the experimental results obtained. The experimental results indicated that bond strength between nanoinclusions reinforced concrete and old concrete can reach 2.85 MPa, which is 0.8 MPa/39.0% higher than that between new concrete without nanoinclusions and old concrete. The reinforcing mechanisms can be attributed to the enrichment of nanoinclusions in the new-to-old concrete interface, compacting the interfacial microstructures and connecting hydration products in micropores of old concrete with that in bulk new concrete. In addition, the prediction model proposed on the basis of reinforcing mechanisms can accurately describe the relationship of the nanoinclusion content and the bond strength of nanoinclusions reinforced concrete with old concrete.

Yes / By controlling the crystallization behavior of poly(lactic acid) (PLA) in the presence of a hydrazide nucleating agent (HNA), PLA-HNA foams with enhanced microcellular structures were prepared via supercritical CO2 foaming. It was found that HNA can self-assemble into fibrillar networks, inducing the crystallization of PLA on their surface, and "shish-kebab"crystalline structures with high crystallinity formed, which can be maintained during the whole foaming process. Incorporation of HNA promoted the formation of gt conformers, improved the amount of dissolved CO2, hindered the escape of CO2, and increased the viscoelasticity of PLA. Compared with neat PLA foam, for PLA-HNA foam, the average cell diameter decreased obviously, from 64.39 to 6.59 μm, while the cell density increased up to nearly three orders of magnitudes, from 6.82 × 106 to 4.44 × 109 cells/cm3. Moreover, lots of fibrillar structures appeared and entangled with each other on the cell wall of the foam. By forming such dense micropores and enhanced fibrillar structures, PLA foam was highly reinforced with significantly improved compressive strength. / This research was financially supported by National Natural Science Foundation of China (grant no. 51773122) and State Key Laboratory of Polymer Materials Engineering (grant no. sklpme2019-2-21).

No description available.

Background: According to the Centers for Disease Control and Prevention (CDC), over one-third of US adults are obese. In order to assess causes of and treatments for obesity, researchers have evaluated a number of processes underlying health-related behaviors, one of which is delay discounting. Delay discounting is a cognitive process that describes the phenomenon by which individuals discount the value of a future reward compared to the value of an immediate reward. Researchers have associated delay discounting with drug addiction, alcoholism, and cigarette smoking. More recently, delay discounting has been studied with regards to health-related behaviors, such as body weight management, food intake, glucose control, and physical activity. While a number of studies have concluded that obese individuals tend to be greater discounters, the relationship between delay discounting and various health-related behaviors beyond smoking and drug use remains unclear. The purpose of this study is to evaluate the relationship between delay discounting and diet quality, glucose tolerance, physical activity, and fasting vs. non-fasting conditions. Methods: Sixty-five males (n=20) and females (n=45) were recruited for the present study. Participants completed two lab sessions: one under non-fasting conditions, and one under fasting conditions which involved measurements of body mass and composition, blood pressure, blood glucose, blood lipids, and health-related questionnaires. Delay discounting and food purchase tasks were completed at both visits. Participants were asked to complete a four-day food intake record and wear a physical activity monitor for four days. Results: Lower rates of discounting were found in those who consumed more total vegetables, and lower food reinforcement was observed in those who spent less time sedentary and more time physically active, had greater dietary Restraint, and had a lower resting heart rate. There were no significant differences between discounting rates and food reinforcement across fasting and non-fasting conditions. / Master of Science / More than one-third of US adults are obese. Obesity brings with it a number of chronic health conditions as well as the financial burden of increased healthcare costs. There are a multitude of treatment methods for obesity, and researches have evaluated many aspects of behaviors that contribute to obesity. Decision-making processes are an important factor related to management of body weight as well as general health. One field of study concerned with decision-making is called behavioral economics, and it includes the concept of delay discounting. Delay discounting is a cognitive process by which individuals tend to discount the value of future rewards in favor of more immediate rewards. This behavior has been associated with drug use and addiction, alcoholism, and cigarette smoking, as well as a number of other psychological or social parameters. More recently, research has connected delay discounting with health-related factors such as body weight management, glucose control, physical activity, and diet quality. A number of studies have concluded that obese individuals tend to be greater discounters, meaning that they prefer immediate rewards rather than delaying gratification for future rewards, however the relationship between delay discounting and various health-related behaviors remains unclear. The purpose of this study is to evaluate the relationship between delay discounting and diet quality, glucose tolerance, physical activity, and fasting vs. nonfasting conditions. Methods: Sixty-five males (n=20) and females (n=45) were recruited for the present study. Participants completed two lab sessions: one under non-fasting conditions, and one under fasting conditions which involved measurements of body mass and composition, blood pressure, blood glucose, blood lipids, and health-related questionnaires. Delay discounting and food purchase tasks were completed at both visits. Participants were asked to complete a four-day food intake record and wear a physical activity monitor for four days. Results: Lower rates of discounting were found in those who consumed more total vegetables, and lower food reinforcement was observed in those who spent less time sedentary and more time physically active, had greater dietary Restraint, and had a lower resting heart rate. There were no significant differences between discounting rates and food reinforcement across fasting and non-fasting conditions.

Cocaine dependence is a major health concern worldwide, but despite this high rate of abuse there are currently no approved therapies for cocaine dependence. Replacement pharmacotherapies are one possible approach for treating cocaine dependence, and identification of such therapeutics for cocaine abuse is the long-term goal of this research. Cocaine binds to, and inhibits uptake at the dopamine (DAT), serotonergic (SERT) and noradrenaline (NET) uptake transporters, but studies have shown that cocaine produces its strong behavioural and positive reinforcing effects through inhibition of the DAT. To this end a great number of diverse, non-selective DAT-inhibiting compounds have been investigated as potential cocaine replacement therapies. It was the initial objective of this research to determine whether the behavioral profile of a novel, selective DAT inhibitor, D-84, fit with that thought for an ideal cocaine replacement therapy. Results indicated that D-84 stimulated locomotor activity, incompletely generalized to the cocaine cue in discrimination tests, attenuated cocaine-self-administration and was self-administered. These observations provide a profile consistent, although perhaps not ideal, with one possible treatment strategy for cocaine dependence. Although it is well established that cocaine predominantly produces its abuse-related effects through inhibition of the DAT, recent evidence suggests that inhibition at the SERT may have modulating effects on the pharmacology of cocaine-like compounds. The second part of this dissertation investigated what effects that increasing SERT inhibition had on the cocaine-like behavioural effects of DAT inhibitors, as a method of determining the fruitfulness of incorporating this feature into future drug candidates to improve them. RTI-55 (DAT Ki 2.7 nM SERT Ki 3 nM) and GBR-12909 (DAT Ki 4.3 nM SERT Ki 73 nM) were selected based on their high and intermediate SERT inhibitory effects, respectively. They were compared in behavioural studies with D-84, which is considered to be a selective DAT inhibitor. The results indicated that although increasing SERT inhibition attenuated locomotor activity effects, it had less effect on cocaine-like discriminative stimulus and reinforcing effects, at least with the doses tested

Syftet med studien är att se om det skolkurativa arbetet influeras av empowerment, det vill säga, om skolkuratorerna arbetar utifrån att stärka elevernas egen kapacitet. För att finna svar har fyra skolkuratorer från två olika kommuner, som är verksamma från grundskola till gymnasienivå intervjuas. Tolkningsramen för analysen av det empiriska materialet utformades efter Adams tre dimensioner för empowermentbaserat socialt arbete. Resultaten visade på att skolkuratorerna hade kännedom om empowerment begreppet och även insikt i vad ett empowerment inriktat arbete bidrar till. Det framkom även att samtliga skolkuratorers arbetssätt innehöll drag av empowerment även om det inte var den uttalade arbetsmetoden och utförandet skilde sig. Studiens slutsats är således att det skolkurativa arbetet uttryckligen inte följer empowerment teori men att det återfinns i arbetssättet. Studien indikerar på att ett behov av vidare forskning kring empowermentbaserade arbetsmetoder och dess applicering inom det skolkurativa arbetet. / The purpose of the study is to see if the school counselors work is influenced by empowerment, that is, if the school counselors aim to strengthen the students' own capacity. Four school counselors from two different municipalities who work from elementary school through high school have been interviewed. The interpretation framework for the analysis of the empirical material was designed according to Adam's three dimensions for empowerment-based social work. The results showed that the school counselors were aware of the empowerment concept and had insight into what empowerment-oriented work contributes to. It also emerged that the work methods of all school counselors contained features of empowerment even though it was not the stated working method and the performance differed. The study concludes that the school counselors work does not explicitly follow empowerment theory but that it is found in the working method. The study indicates a need for further research on empowerment-based working methods and its application in school counseling.

Energy intake (EI) and energy expenditure (EE) across the menstrual cycle (MC), while considering body adiposity, have not been previously evaluated in the same individuals. This study mainly examined the variations in energy balance (EB) across MC. Seventeen women (Body fat-DXA:28.5%) participated in three identical sessions during distinct phases of the MC: Early-follicular, Late-follicular/ovulation and Mid-luteal (confirmed by basal temperature and sex-steroid hormones). EI, resting metabolic rate (RMR), physical-activity EE (PAEE), severity of PMS, leptin and relative-reinforcing value (RRV) of preferred foods were measured during each phase. No differences in body fat, EI, RMR, PAEE, leptin and RRV of food were noted across MC. Trends were noted in preferred snack (p=0.06) and combined snack/fruit (p=0.06) intakes, while differences were noted in severity of PMS (p<0.05) across phases. Changes in EB across the MC were not noted. PMS was more severe, and preferred snack and combined snack/fruit intakes were slightly higher during mid-luteal phase.

Energy intake (EI) and energy expenditure (EE) across the menstrual cycle (MC), while considering body adiposity, have not been previously evaluated in the same individuals. This study mainly examined the variations in energy balance (EB) across MC. Seventeen women (Body fat-DXA:28.5%) participated in three identical sessions during distinct phases of the MC: Early-follicular, Late-follicular/ovulation and Mid-luteal (confirmed by basal temperature and sex-steroid hormones). EI, resting metabolic rate (RMR), physical-activity EE (PAEE), severity of PMS, leptin and relative-reinforcing value (RRV) of preferred foods were measured during each phase. No differences in body fat, EI, RMR, PAEE, leptin and RRV of food were noted across MC. Trends were noted in preferred snack (p=0.06) and combined snack/fruit (p=0.06) intakes, while differences were noted in severity of PMS (p<0.05) across phases. Changes in EB across the MC were not noted. PMS was more severe, and preferred snack and combined snack/fruit intakes were slightly higher during mid-luteal phase.