3D Seismic Interpretation, Mechanical Stratigraphy and Production Analysis of the Marcellus Shale in Northern West Virginia

The Marcellus shale is one of the most developed unconventional shale gas reservoirs in the world with a calculated 84.5 trillion cubic feet in proved natural gas reserves in Pennsylvania and West Virginia. To better exploit this resource all geological aspects of the Marcellus shale are being studied. In this study, mechanical stratigraphy and interpreted seismic fracture zones within the Marcellus shale are examined. These geologic criteria are assessed for potential to impact gas production by analyzing the gas production of fourteen horizontal Marcellus shale wells within and around the study area.;Mechanical stratigraphy is evaluated from the top of the Tully limestone to the base of the Onondaga limestone to assess vertical heterogeneity of brittleness within and around the Marcellus shale. Brittleness estimations are derived from petrophysical well logs including bulk density, shear velocity and compressional velocity. Mineralogy assessment is completed using Schlumberger\u27s SpectroLithRTM gamma ray spectroscopy mineralogy logs. Elastic moduli including Young\u27s modulus, Poisson\u27s ratio and Lame\u27s parameters are assessed in terms of brittleness and total organic content to develop constraints for areas of high brittleness and high total organic content. The constraints developed at the study well are compared to studies at four other unconventional shale gas sites. The results suggest that mechanical properties are variable and site dependent. Conclusive ranges for Poisson\u27s ratio and Young\u27s modulus constraints for areas of high brittleness and high total organic cannot be developed for an entire shale play but may be useful in local analyses.;Seismic discontinuities were extracted from two three dimensional seismic surveys using a post-stack processing workflow that included Ant-Tracking. They are interpreted to be associated with small faults and fracture zones. The relationship between the number of seismic discontinuities intersecting horizontal wells in the Marcellus shale and cumulative gas production was evaluated. Number of intersecting discontinuities per 1000 feet of wellbore is linearly correlated to cumulative gas production with R2 values greater than 0.9

Relevance of basic laboratory and clinical research activities as part of the vascular surgery fellowship: An assessment by program directors and postfellowship surgeons

AbstractIntroduction: Decreased federal monies for graduate medical education, increased clinical training demands, and a decreased pool of general surgery trainees applying to vascular surgery fellowships have brought into question the relevance of the fellowship research experience. This study sought to describe the recent laboratory experience of the fellows, the value of this experience to program directors (PDs) and the trainees, and what factors related to this experience contributed to the trainee entering an academic career versus a private practice career. Methods: A survey regarding the relevance of research experience during fellowship training was mailed in 2001 to all Accreditation Council for Graduate Medical Education-approved vascular surgery fellowship PDs and vascular surgery fellows (VSFs) from 1988 to 2000 applying for the American Board of Surgery Certificate of Added Qualification in General Vascular Surgery. Results: Survey responses were received from 89% of the PDs (74/83) and 69% of the VSFs (259/378). Among the PDs, 70% had completed an approved fellowship, and current bench research was performed by 46%. The PDs afforded protected research time to 69% of the VSFs (with a mean duration of 12 months). This research was in the basic science laboratory 34% of the time. Only 42% of the PDs considered basic laboratory research to be an important part of the fellowship, whereas 99% believed that clinical research was important. Among the PDs, 42% believed that more practice-oriented fellowships with no basic research were needed, whereas 35% believed that basic research should remain an integral component of the fellowship. VSF basic science productivity was significantly greater from those programs that offered protected research time as compared with those that did not (mean basic science paper published, 1.7 ± 0.1 versus 0.3 ± 0.6 per VSF; P < .001). At the time of the survey, 99 VSFs had entered academic careers and 136 were in private practice. Basic science research had been undertaken by 56% of the VSFs during medical school and by 53% during general surgery residency. Research during the fellowship was performed by 65% of the VSFs. This experience was considered helpful in choosing an academic or private practice career by 44% of the VSFs. A greater proportion of academic surgeons had research experience as VSFs when compared with VSFs who became private practitioners (71% versus 57%; P < .05). VSFs who entered academic careers had a more productive publication record in fellowship than did those who chose private practice (mean paper, 2.4 versus 1.5; P < .05). Overall, 78% of the VSFs believed that their research experience was maturing beyond the technical skills learned. Conclusion: This report provides a benchmark of the vascular surgery fellowship research experience. Most VSFs considered the research experience as it now exists to be worthwhile, and less than half of the PDs believed that it should remain as it is. Research experience in fellowship seemed more influential than that in medical school or general surgical residency in promoting an academic career. (J Vasc Surg 2002;36:1083-91.

Noise and Bell's inequality

From the beginning of quantum mechanics, there has been a discussion about the concept of reality, as exemplified by the EPR paradox. To many, the idea of the paradox and the possibility of local hidden variables was dismissed by the Bell inequality. Yet, there remains considerable evidence that this inequality can be violated even by classical systems, so that experiments showing quantum behavior and the violation of the inequality must be questioned. Here, we demonstrate that classical optical polarization experiments based upon noise in the system can be shown to violate the Bell inequality.Comment: Fluctuation and Noise Letters, in pres

Characteristics and Motivational Factors of Effective Extension Advisory Leaders: Implications for Building Strong Extension Advisory Councils

The purpose of this study was to determine the characteristics and motivational factors of effective Extension advisory leaders. This Delphi study was conducted with a selected group of County Extension Directors and a group of Extension State Advisory Leaders. The study identified 10 characteristics that distinguish an effective Extension advisory leader. Some of these characteristics are explicit and easy to observe, while others are implicit and difficult to directly observe. Therefore, it is practical to use directly observable characteristics of effective advisory leaders when selecting volunteers. Once potential volunteers are spotted in the community, implicit characteristics of effective advisory leaders should be used to further screen them before they are selected. The study also identified the eight most important factors motivating individuals to volunteer as effective advisory leaders. Understanding these motivational factors is helpful for creating an environment for attracting and retaining effective volunteers. Understanding their motivation for volunteer work and creating an environment for them to meet the motivating factors for volunteering will lead to volunteer satisfaction and retention. The findings of this study can be used to build strong Extension advisory councils

The stator complex of the A1A0-ATP synthase--structural characterization of the E and H subunits.

Archaeal ATP synthase (A-ATPase) is the functional homolog to the ATP synthase found in bacteria, mitochondria and chloroplasts, but the enzyme is structurally more related to the proton-pumping vacuolar ATPase found in the endomembrane system of eukaryotes. We have cloned, overexpressed and characterized the stator-forming subunits E and H of the A-ATPase from the thermoacidophilic Archaeon, Thermoplasma acidophilum. Size exclusion chromatography, CD, matrix-assisted laser desorption ionization time-of-flight mass spectrometry and NMR spectroscopic experiments indicate that both polypeptides have a tendency to form dimers and higher oligomers in solution. However, when expressed together or reconstituted, the two individual polypeptides interact with high affinity to form a stable heterodimer. Analyses by gel filtration chromatography and analytical ultracentrifugation show the heterodimer to have an elongated shape, and the preparation to be monodisperse. Thermal denaturation analyses by CD and differential scanning calorimetry revealed the more cooperative unfolding transitions of the heterodimer in comparison to those of the individual polypeptides. The data are consistent with the EH heterodimer forming the peripheral stalk(s) in the A-ATPase in a fashion analogous to that of the related vacuolar ATPase

Why We Read Wikipedia

Wikipedia is one of the most popular sites on the Web, with millions of users relying on it to satisfy a broad range of information needs every day. Although it is crucial to understand what exactly these needs are in order to be able to meet them, little is currently known about why users visit Wikipedia. The goal of this paper is to fill this gap by combining a survey of Wikipedia readers with a log-based analysis of user activity. Based on an initial series of user surveys, we build a taxonomy of Wikipedia use cases along several dimensions, capturing users' motivations to visit Wikipedia, the depth of knowledge they are seeking, and their knowledge of the topic of interest prior to visiting Wikipedia. Then, we quantify the prevalence of these use cases via a large-scale user survey conducted on live Wikipedia with almost 30,000 responses. Our analyses highlight the variety of factors driving users to Wikipedia, such as current events, media coverage of a topic, personal curiosity, work or school assignments, or boredom. Finally, we match survey responses to the respondents' digital traces in Wikipedia's server logs, enabling the discovery of behavioral patterns associated with specific use cases. For instance, we observe long and fast-paced page sequences across topics for users who are bored or exploring randomly, whereas those using Wikipedia for work or school spend more time on individual articles focused on topics such as science. Our findings advance our understanding of reader motivations and behavior on Wikipedia and can have implications for developers aiming to improve Wikipedia's user experience, editors striving to cater to their readers' needs, third-party services (such as search engines) providing access to Wikipedia content, and researchers aiming to build tools such as recommendation engines.Comment: Published in WWW'17; v2 fixes caption of Table