Renal cell carcinoma

This issue of eMedRef provides information to clinicians on the pathophysiology, diagnosis, and therapeutics of renal cell carcinoma

Investigating the effect of chronic activation of AMP-activated protein kinase in the liver

Obesity and its associated complications, are an increasing global problem. Non-alcoholic fatty liver disease (NAFLD), the hepatic component of the Metabolic Syndrome currently affects an estimated 25% of the world’s population, with 2% of those affected dying from a NAFLD liver related cause, such as hepatocellular cancer (HCC). AMP-activated protein kinase (AMPK), a master regulator of energy homeostasis that regulates anabolic and catabolic pathways in response to ATP depletion has received substantial attention as a therapeutic target in treatment of the Metabolic Syndrome. More recently, a growing number of studies have focussed on the role of AMPK in cancer. This study has characterised a novel, activating mutation in the γ1 subunit of AMPK (D316A). Mice which express this mutation specifically in the liver (D316-Tg) have been used to investigate the effects of chronic hepatic AMPK activation under basal conditions and in response to the metabolic stresses of hypercaloric, high fat and lipogenic, high fructose diets. D316A-Tg mice have also been crossed with mice with liver specific Phospatase and tensin homologue (Pten) loss to evaluate the role of AMPK in NAFLD related HCC. Fatty acid synthesis was reduced in hepatocytes isolated from D316A-Tg mice and these mice were protected from hepatic steatosis under lipogenic conditions. Fatty acid oxidation in hepatocytes was unaffected by increased AMPK activity and correspondingly D316A-Tg mice were not protected from hepatic lipid accumulation, following high fat feeding. Increased hepatic AMPK activity also attenuated steatohepatitis and had a marked inhibitory effect on tumourgenesis in mice with liver specific Pten loss. Further work is required to elucidate the precise role of AMPK in tumour development. However, the findings of this study suggest that activation of AMPK in the liver may inhibit NAFLD progression and tumourgenesis and support the development of pharmacological, specific AMPK activators for use in these settings.Open Acces

The Effect of Corrosion Defects on the Failure of Oil and Gas Transmission Pipelines: A Finite Element Modeling Study

The transportation of oil and gas and their products through the pipelines is a safe and economically efficient way, when compared with other methods of transportation, such as tankers, railroad, trucks, etc. Although pipelines are usually well-designed, during construction and later in service, pipelines are subjected to a variety of risks. Eventually, some sections may experience corrosion which can affect the integrity of pipeline, which poses a risk in high-pressure operations. Specifically, in pipelines with long history of operation, the size and location of the corrosion defects need to be determined so that pressure levels can be kept at safe levels, or alternatively, a decision to repair or replace the pipe section can be made. To make this decision, there are several assessment techniques available to engineers, such as ASME B31G, MB31G, DNV-RP, software code called RSTRENG. These assessment techniques help engineers predict the remaining strength of the wall in a pipe section with a corrosion defect. The corrosion assessment codes in the United States, Canada and Europe are based on ASME-B31G criterion for the evaluation of corrosion defects, established based on full-scale burst experiments on pipes containing longitudinal machined grooves, initially conducted in 1960s. Because actual corrosion defects have more complex geometries than machined grooves, an in-depth study to validate the effectiveness of these techniques is necessary. This study is motivated by this need. The current study was conducted in several stages, starting with the deformation behavior of pipe steels. In Phase 1, true-stress-true plastic strain data from the literature for X42 and X60 steel specimens were used to evaluate how well four commonly used constitutive equations, namely, those developed by Hollomon, Swift, Ludwik and Voce, fit the experimental data. Results showed that all equations provided acceptable fits. For simplicity, the Hollomon equation was selected to be used in the rest of the study. In Phase 2, a preliminary finite element modeling (FEM) study was conducted to compare two failure criteria, stress-based or strain-based, performed better. By using data from the literature for X42 and X60 pipe steels, experimental burst pressure data were compared with predicted burst pressure data, estimated based on the two failure criteria. Based on this preliminary analysis, the stress-based criterion was chosen for further FEM studies. In Phase 3, failure data from real corrosion pits in X52 pipe steels with detailed profiles were used to develop a FEM scheme, which included a simplified representation of the defect. Comparison of actual and predicted burst pressures indicated a good fit, with a coefficient of determination (R2) level of 0.959. In Phase 4, burst pressure levels were estimated for real corrosion pits for the experiments from the same study as in Phase 3, but only with corrosion pit depths and length and without corrosion widths. Widths were estimated from the data used in Phase 3, by using an empirical equation as a function of pit length. There was significant error between experimental and predicted burst pressure. Errors in Phases 3 and 4 were compared statistically. Results showed that there is a statistically significant difference in the error when the width of the corrosion pit is unknown. This finding is significant because none of the assessment techniques in the literature takes width into consideration. Subsequently, a parametric study was performed on three defect geometries from the same study in Phase 3. The pit depths and lengths were held constant but widths were changed systematically. In all cases, the effect of the pit width on burst pressure was confirmed. In Phase 5, the three assessment techniques, ASME B31G, MB31-G and DNV-RP were evaluated by using experimental test results for X52 pipe. Synthetic data for deeper pits were developed by FEM and used along with experimental data in this phase. Two types of the error were distinguished to classify defects. Type I errors (α) and Type II errors (β) were defined using Level 0 evaluation method. Results showed that although ASME B31G is the most conservative technique, it is more reliable for short defects than MB31G and DNV-RP. The least conservative technique was DNV-RP but it yielded β error, i.e., the method predicted a safe operating pressure and pipe section would fail. Therefore, DNV-RP is not recommended for assessment of steel pipes, specifically for X52 pipes

Tamoxifen or Estradiol Limited to the Induction Phase of Nicotine Sensitization Enhances the Expression of Locomotor Sensitization in Ovariectomized and in Intact Female Rats

In both humans and rodents, females are more vulnerable to addiction than males, which has been linked to higher concentrations of the hormone estradiol in females. In rats, nicotine injections produce greater sensitization (neurological changes responsible for drug cravings) in females than in males, which could contribute to sex differences in susceptibility to addiction. The purpose of these experiments was to investigate the effects of estradiol during three nicotine injections (two consecutive days and a third injection nine days later). Results from these experiments indicate that depletion of estradiol via ovariectomy attenuates nicotine sensitization in females, which can be rescued by estradiol injection limited to the induction phase of sensitization. Administration of tamoxifen (antagonist at nuclear estradiol receptors, agonist of the membrane-bound estradiol receptor GPER1) did not alter sensitization in gonadally intact rats, and was sufficient to restore expression of sensitization in ovariectomized females (similar to estradiol). Findings from these experiments indicate that the enhancing effects of estradiol on nicotine sensitization occur during the induction phase, and may be mediated by membrane bound estrogen receptors (e.g., GPER1)

Alien Registration- Thompson, Jennet W. (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/21438/thumbnail.jp

Butterfly community temporal trends and responses to resource availability along a hydrologic gradient of montane meadows

Butterfly species have proven to be useful indicators of environmental change in many ecosystems. Their tight association with plant communities and their sensitivity to microclimates can provide insight regarding changes in landscape or vegetative composition. Here we report on a study within two regions of the Greater Yellowstone Ecosystem where butterflies have been surveyed in montane meadows along a hydrological gradient since 1997. We have studied this system to better understand butterfly community ecology within one of the most pristine meadow systems in the lower 48 of the United States. This research examined the temporal and spatial patterns of montane meadow butterfly communities in relation to meadow moisture availability and quantity of floral and larval host plant resources. This information is a valuable tool for conservation of montane meadows, and could be useful in monitoring meadow changes due to climatic, anthropogenic, or other natural changes in the landscape

The Value of Public Sector Annual Reports and Annual Reporting Awards as a Signal of Management Performance

Australian public sector reforms have emphasised the accountability of agencies for the performance of management. Despite considerable diversity in public sector organisations, annual reports have been promoted as an appropriate tool to discharge the accountability of all government agencies. However, there remains an absence of consistent empirical evidence as to the value of the annual report for reporting on management performance. Further, debates about the role of public sector annual reports often become intertwined with notions of the quality of reports. Prior research has investigated the incentives of agencies to enter annual reporting awards as a means of signalling the quality of management. However, the research ignores the possibility that the value of annual reports to discharge performance accountability and the value of entry into an annual reporting award may vary depending on the type of public sector agency and on the relationships between stakeholders. This study focuses on the Queensland public sector and the Queensland Annual Reporting Award (QARA) and uses a series of case studies to examine the value of the annual report as a means of discharging accountabilities. The results reveal a cross sectional variation in the perceived value of the annual report in discharging accountabilities. In some cases it was thought that alternative forms of communication provided a more suitable means to discharge the accountability demands of stakeholders. Further, while annual reporting awards provide a mechanism to supply a credible signal of quality, it will only be used in those situations where the participants identify direct benefits of entry

Rural tourism support, size, and geographic characteristics impact on tourism development

Main purpose of this investigate what is the impact and the benefits of EU sponsorship to rural tourism Hosts. More of that is examines if the size and geographical characteristics of rural tourism host enterprises affects how positive are hosts on rural tourism development. To answer to the hypotheses a questionnaire was developed then a factor analysis was implemented to discover the most important questions to define “successful rural tourism development”. Then T-Test and ANOVA test was applied to examine if hypothesis one will be accepted or no. Our population was 652 rural tourism hosts and 174 replied giving a response rate of 27%. Findings revealed that subsiding, size and peripheral economic condition are significantly influencing the respondents' views for and against the topic of successful rural enterprises factors. Significant differences based on size do exist in the case of skillful persons who manage well the available resources and they ensure the right management of the financial capitals

The impact of EU sponsorship, size, and geographic characteristics on rural tourism development

© 2019 by the authors. The main purpose of this study was to investigate the factors that promote successful rural tourism development in light of EU sponsorship of rural tourism hosts. The paper examines the effect of the size and geographical characteristics of rural tourism hosts on their views towards rural tourism development. The paper employs factor analysis, t-tests, and ANOVA to analyze the data from the survey of the hosts. The survey was sent to 652 rural tourism hosts, of whom 174 replied, giving a response rate of 27%. The results show the following. Firstly, subsidies, leadership, and cooperation are viewed by the hosts as important factors. Secondly, sponsorship, size, and peripheral economic conditions influence rural tourism hosts\u27 views on success factors of rural enterprises

Factors influencing the intention to use cryptocurrency payments: An examination of blockchain economy

In summary, this study has applied TAM model to examine cryptocurrency payment adoption in Taiwanese hotels, examining the factors that are more likely to affect the behavioral intent. The empirical results suggest that intent to adopt cryptocurrency payments is affected by perceived usefulness, and perceived ease of use of these payments. In turn, perceived usefulness is affected by trust towards these payments. Interestingly, perceived usefulness was not shown to be significantly affected by different types of risks associated with cryptocurrency payments, including financial risk, technological risk, and social risk. Perceived ease of use, in turn, is affected by convenience of cryptocurrency payments; and is not shown to be significantly affected by trust