Physical Transport and Chemical Behavior of Dispersed Oil

During response operations, scientific information is provided to decision makers, such as the Federal On-Scene Coordinator (FOSC), state and federal trustees, and the public. The decision to use chemical dispersants during a response is made among all these parties, and during the Deepwater Horizon (DWH) oil spill the dispersant discussion included both surface and subsurface application of chemical dispersants. This paper is intended to provide perspective on research needs considered pre- and post-DWH oil spill related to response modeling and data collection needs for decision support of dispersant application and its potential effects. Given time constraints for implementing models and sampling strategies for response, requirements for data and types of questions to be addressed may be significantly different than requirements for research or damage assessment activities. At the time of this writing, just over a year after the successful response operations to cap the well, many studies are still in progress, and data are still being collected and evaluated to assess dispersant effectiveness and possible impacts. More information and research results will become available over the next months to years. Thus these research needs, as summarized for this workshop, should be evaluated again at a later time

Amplitude death criteria for coupled complex Ginzburg-Landau systems

Amplitude death, which occurs in a system when one or more macroscopic wavefunctions collapse to zero, has been observed in mutually coupled solid-state lasers, analog circuits, and thermoacoustic oscillators, to name a few applications. While studies have considered amplitude death on oscillator systems and in externally forced complex Ginzburg-Landau systems, a route to amplitude death has not been studied in autonomous continuum systems. We derive simple analytic conditions for the onset of amplitude death of one macroscopic wavefunction in a system of two coupled complex Ginzburg-Landau equations with general nonlinear self- and cross-interaction terms. Our results give a more general theoretical underpinning for recent amplitude death results reported in the literature, and suggest an approach for tuning parameters in such systems so that they either permit or prohibit amplitude death of a wavefunction (depending on the application). Numerical simulation of the coupled complex Ginzburg-Landau equations, for examples including cubic, cubic-quintic, and saturable nonlinearities, is used to illustrate the analytical results.Comment: 7 pages, 4 figure

IRT assessment of readiness for interprofessional learning scale (RIPLS) : dimensionality, reliability, and item function

This poster presentation aims to bring evidence from modern psychometric methods to bear on a popularly deployed questionnaire in interprofessional education (IPE) assessment. Specifically, three interrelated problems raised against the Readiness for Interprofessional Learning Scale (RIPLS) are examined in a study with n =280 medical and nursing student participants. Firstly, findings indicate a strong, general factor underlying the RIPLS that supports unidimensional interpretations. Secondly, findings support RIPLS overall reliability, but fail to support subscale reliabilities. Thirdly, findings support the RIPLS potential sensitivity to changes with appropriate lower ranges for our pre-training student sample. Recommendations for refinement to the RIPLS include: use of more appropriate reliability indices; factor generalizability; and a subset of items. More generally, refinement is possible, whereas RIPLS disuse or continued misuse with problematic scales is likely to hinder progress in the field of IPE research

Cultural Resources Report for the Cane Island Branch Section of the Buffalo Bayou Project Between Katy-Flewellen Road and Kingsland Boulevard in Fort Bend County, Texas

Gray & Pape, Inc., of Houston, Texas, under contract with BIO-WEST, Inc., has prepared the following report on cultural resources management activities in Fort Bend County, Texas. The project includes an archaeological survey of a total of approximately 0.93 kilometers (0.58 miles) along Buffalo Bayou between Katy-Flewellen Road and Kingsland Boulevard in Katy, Texas. The archaeological Area of Potential Effects is defined as the maintenance corridor, 30 to 60 meters (98 to 196 feet) long. The goal of this study was to assist Fort Bend County, the Texas Historical Commission, and the lead federal agency in determining whether or not intact cultural resources are present within areas for construction, and if so to provide management recommendations for these resources. All activities described herein were subject to Section 106 of the National Historic Preservation Act and issuance of an Antiquities Permit for Archeology (Permit 9319) applied for by Gray & Pape, Inc. on February 13, 2020, and issued by the Texas Historical Commission. No diagnostic or non-diagnostic artifacts were collected in the course of the current survey. As a project permitted through the Texas Historical Commission; however, Gray & Pape, Inc. submitted project records to the Center of Archaeological Studies at Texas State University. The Natural Resource Conservation Service is the lead federal agency for the project. Fieldwork was conducted between March 12 and March 16, 2020 and required approximately 40- person hours to complete. Subsurface testing included a combination of systematic shovel testing and judgement sample auger probing. The site file research revealed two previously recorded archaeological sites (41FB101 and 41FB102) are located within the project area. At the beginning of the survey, an initial attempt was made to relocate previously recorded Sites 41FB101 and 41FB102 through surface inspection and limited shovel testing across the Area of Potential Effects along both sides of Buffalo Bayou. Recent disturbances from mechanical excavation along the channel slopes, the dumping of spoil across the surface of the two-track right-of-way along the bayou, and the active installation of sheet piling were photographed and mapped. Sites 41FB101 and 41FB102 could not be relocated within the Area of Potential Effects during the surface inspection, shovel testing or auger probing. No other historic or prehistoric artifacts or cultural features were identified as a result of this survey. During the initial reconnaissance, Rangia shells (n=8), including whole (closed) specimens and half shell, were observed on the surface in an area recently disturbed by heavy machinery. The shells were located east of Site 41FB101 along the two-track right-of-way and slope of the east bank of Buffalo Bayou. The majority of them were smaller than 3 centimeters (1.2 inches), with one whole specimen measuring approximately 6 centimeters (2.4 inches). Surface and subsurface inspection in the immediate area of these specimens failed to find evidence of associated cultural features or artifacts on the surface or in a buried context. A variety of modern bricks and brick fragments were also observed along the inner slopes of the east bank near the shell scatter. These same materials were later observed among the variety of riprap materials along the west bank of the bayou west of Site 41FB102 near a residential property immediately adjacent to the Area of Potential Effects. No additional cultural materials were observed on the surface with the exception of modern debris including plastics and aluminum cans. Gray & Pape, Inc. is not recommending a site designation for the Rangia shell or brick scatter observed during the survey for the foregoing reasons:1) there were no intact, buried deposits or features found; 2) there was no material that could be positively identified as artifacts; 3) the bricks observed were modern and likely deposited by landowners in attempts to prevent erosion; 4) the size, quantity, and inclusion of whole Rangia identified on the surface appear to be natural occurrences as opposed to the remains of an archaeological deposit or feature; and 5) it is impossible to determine the original location of the shell specimens at this time. Based on the results of this investigation, Sites 41FB101 and 41FB102 do not appear to extend into the existing easement belonging to the Fort Bend County Drainage District. Instead, both sites appear to be located on private property outside of the project Area of Potential Effects. As such, these sites have not been evaluated for National Register eligibility, but Gray & Pape, Inc. recommends that there will be no direct impact to these sites. It is also recommended that because the majority of project impacts will occur within sediments that have been repeatedly impacted by past channelization activities, the potential to identify intact, significant cultural resources is low. Gray & Pape, Inc. recommends the project be allowed to proceed as currently planned. As a protective measure during construction, highvisibility temporary fencing should be installed against the edge of the Area of Potential Effects in the vicinity of the two known sites. No additional cultural resources activities are recommended unless project plans change

Out of the Vault: Developing a Wikipedia Edit-a-thon to Enhance Public Programming for University Archives and Special Collections

Academic libraries are more cognizant of their public program offerings than ever before. How does this shift impact the university archives and special collections? How does this area of the academic library meet the challenge of public programming that engages their users with their core missions? At Eastern Washington University (EWU), a regional comprehensive university, library and archives staff collaborated to develop a Wikipedia edit-a-thon that would provide an opportunity for undergraduate students to 1) expose them to archival materials, and 2) provide them with experience in collaborative knowledge creation. This article reviews the literature on the use of the Wikipedia platform and edit-a-thon events by cultural heritage institutions (libraries, archives, and museums), as well as the literature on public programming for archives and special collections. It details the steps taken to organize the event held at EWU, and reflects on the implications of this type of outreach and public programming event for archives and special collections in academic libraries

Concurrent formation of supermassive stars and globular clusters : implications for early self-enrichment

19 pages, 5 figures, accepted to MNRAS (shortened abstract and included feedback from the community)We present a model for the concurrent formation of globular clusters (GCs) and supermassive stars (SMSs, ≳10 3M ⊙) to address the origin of the HeCNONaMgAl abundance anomalies in GCs. GCs form in converging gas flows and accumulate low-angular momentum gas, which accretes on to protostars. This leads to an adiabatic contraction of the cluster and an increase of the stellar collision rate. A SMS can form via runaway collisions if the cluster reaches sufficiently high density before two-body relaxation halts the contraction. This condition is met if the number of stars ≳10 6 and the gas accretion rate ≳10 5M ⊙ Myr -1, reminiscent of GC formation in high gas-density environments, such as - but not restricted to - the early Universe. The strong SMS wind mixes with the inflowing pristine gas, such that the protostars accrete diluted hot-hydrogen burning yields of the SMS. Because of continuous rejuvenation, the amount of processed material liberated by the SMS can be an order of magnitude higher than its maximum mass. This 'conveyor-belt' production of hot-hydrogen burning products provides a solution to the mass budget problem that plagues other scenarios. Additionally, the liberated material is mildly enriched in helium and relatively rich in other hot-hydrogen burning products, in agreement with abundances of GCs today. Finally, we find a super-linear scaling between the amount of processed material and cluster mass, providing an explanation for the observed increase of the fraction of processed material with GC mass. We discuss open questions of this new GC enrichment scenario and propose observational tests.Peer reviewe

Retrospective file review shows limited genetic services fails most patients – an argument for the implementation of exome sequencing as a first-tier test in resource-constraint settings

Background: Exome sequencing is recommended as a first-line investigation for patients with a developmental delay or intellectual disability. This approach has not been implemented in most resource-constraint settings, including Africa, due to the high cost of implementation. Instead, patients have limited access to services and testing options. Here, we evaluate the effectiveness of a limited genetic testing strategy and contrast the findings to a conceivable outcome if exome sequencing were available instead. Results: A retrospective audit of 934 patient files presenting to a medical genetics clinic in South Africa showed that 83% of patients presented with developmental delay as a clinical feature. Patients could be divided into three groups, representing distinct diagnostic pathways. Patient Group A (18%; mean test cost $131) were confirmed with aneuploidies, following a simple, inexpensive test. Patient Group B (25$140) presented with clinically recognizable conditions but only 39% received a genetic diagnostic confirmation due to limited testing options. Patient Group C – the largest group (57%; mean test cost $337) – presented with heterogenous conditions and DD, and 92% remained undiagnosed after limited available testing was performed. Conclusions: Patients with DD are the largest group of patients seen in medical genetics clinics in South Africa. When clinical features are not distinct, limited testing options drastically restricts diagnostic yield. A cost- and time analysis shows most patients would benefit from first-line exome sequencing, reducing their individual diagnostic odysseys

Shovel-truck cycle simulation methods in surface mining

This study investigates the main factors of production, their interaction and influence on cycle time efficiency for shovel-truck systems on surface mines. The main factors are truck payload, cycle time and operator proficiency. It is now routine that shoveltruck cycles are analysed using simulation methods. The Elbrond, FPC, Talpac, Arena and Machine Repair simulation models are discussed to explain how their model characteristics contribute to the differences in their reported cycle efficiency as indicated by productivity results. The Machine Repair Model based on Markov chains is adapted for shovel-truck systems and examined for calculating shovel-truck cycle times. The various probability distributions that can be use to model particular cycle time variables and some methods in selecting the “best” fit are examined. Truck cycle time variable sensitivity is examined by using the Excel® add-on program @Risk (Palisade Corp.) in determining their respective weighting or contribution within the total cycle time variability. The analysis of cycle efficiency leads ultimately to sizing of a shovel-truck system. When determining a fleet size for a particular surface operation the planning engineers will tend to use one and to a lesser extent perhaps two separate simulation models. This study calculates the productivity (tonnes per hour) for a “virtual mine” with a variable number of trucks, variable cycle distances and variable truck loading times. The study also includes a separate analysis of cycle time variables and their probability distributions for the Orapa diamond mine in Botswana, to show possible distributions for various cycle variables. The study concludes with a calculation of the truck fleet size using the Elbrond, FPC, Talpac and Arena and Machine Repair models for the Optimum Colliery coal mine and then compares the results and their correlation. The main findings are that the calculation of waiting time is different for the various models, each model yields a unique fleet sizing solution and any solution in effect represents a range of results