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Oilfield water and oil tracers have historically been pumped into the fracturing fluid during well stimulation. This paper will introduce an alternative method of injecting oilfield tracers that utilizes perforating guns with energetic propellant to force the tracer into a perforation cluster prior to fracturing operations. Direct tracer injection from perforating guns offers several advantages to operators that are interested in oilfield tracer diagnostics, they include: Monitoring a wells oil or water returns down to an individual cluster level of resolution. Energetic propellent assisted perforation cluster breakdown. Direct tracer injection into clusters for wells that are: Perforated but not hydraulically fractured. Bullhead refracturing treatments with long open intervals of newly fired perforations. Not sufficiently isolated between stages from poor cementing or leaking plugs. Not isolated or experimentally isolated between stages. Oilfield tracers in solid form were first injected into perforation clusters with energetic propellants on two Marcellus Shale wells. The primary purpose of this experiment was to determine if Perforation Gun Tracing (PGT) could be used to provide flow-assurance diagnostic information to the well operator. Additionally, standard liquid water tracers were also injected into the flowstream during the corresponding fracture treatment stages and used as a control for the PGT. Both tracer injection methods indicated that the toe side of the wellbore was contributing to the fluid returns profile and also showed similar trends in tracer response over time. This experiment showed that PGT could provide valuable diagnostic information to well operators. Several additional field trials that exploit the unique benefits of PGT were completed after the success of the initial experiment and are included in the case studies section of the paper. In each case, PGT was able to provide the intended diagnostic which included flow-assurance, flow-profiling, fracture driven interactions and/or refracturing effectiveness. In refracturing, PGT has tremendous benefits because the energetic propellent can help the new perforations breakdown and compete with the existing broken down and eroded perforations. Additionally, unique tracers are injected at several known cluster depths throughout the lateral. Any returns of the unique tracers in the flowback water will correspond to fracturing fluid that has contacted the depth of that specific traced cluster. This provides an operator valuable diagnostic information to determine how deep their refracture treatment was able to reach into the lateral. PGT also delivers information on the returns of an individual cluster, without post-frac well intervention or permanent hardware installation.

The first Paraguayan records of the Broad-winged Hawk Buteo platypterus are reported from Itapúa and Central departments.

To aid understanding of the effect of antiviral treatment on population-level influenza transmission, we used a novel pharmacokinetic–viral kinetic transmission model to test the correlation between nasal viral load and infectiousness, and to evaluate the impact that timing of treatment with the antivirals oseltamivir or baloxavir has on influenza transmission. The model was run under three candidate profiles whereby infectiousness was assumed to be proportional to viral titer on a natural-scale, log-scale, or dose–response model. Viral kinetic profiles in the presence and absence of antiviral treatment were compared for each individual (N = 1000 simulated individuals); subsequently, viral transmission mitigation was calculated. The predicted transmission mitigation was greater with earlier administration of antiviral treatment, and with baloxavir versus oseltamivir. When treatment was initiated 12–24 hours post symptom onset, the predicted transmission mitigation was 39.9–56.4% for baloxavir and 26.6–38.3% for oseltamivir depending on the infectiousness profile. When treatment was initiated 36–48 hours post symptom onset, the predicted transmission mitigation decreased to 0.8–28.3% for baloxavir and 0.8–19.9% for oseltamivir. Model estimates were compared with clinical data from the BLOCKSTONE post-exposure prophylaxis study, which indicated the log-scale model for infectiousness best fit the observed data and that baloxavir affords greater reductions in secondary case rates compared with neuraminidase inhibitors. These findings suggest a role for baloxavir and oseltamivir in reducing influenza transmission when treatment is initiated within 48 hours of symptom onset in the index patient.

Perforating cemented casing is a staple for completing wells in every major basin in North America. The objective is to provide a highly conductive pathway between the wellbore and the target formation for both the stimulation and production fluids. New technology, statistical analysis, experimentation and trial-and-error are all used to find the optimal method for creating this pathway. Diagnostics like proppant tracers, downhole cameras, distributed temperature sensing (DTS), distributed acoustic sensing (DAS) and perforation friction pressure analysis can also be used to help evaluate the successes associated with the different methods for perforating. New technology in creating consistent hole perforations in a horizontal wellbore, without the need for mechanical centralization or positioning systems, has recently been developed. This method of perforating employs a specialty shaped charge that allows for more control in the distribution of entry hole diameter (EHD) across a given cluster. This provides operators a more predictable and consistent pathway from the wellbore to the formation. Not only is a consistent hole desirable in a standard multi-cluster stage treatment, but other recent completions trends can also benefit from increased precision in perforating. High density perforating (HDP) is being used in order to create more transverse fractures along the length of the well. A consistent hole allows for more precise estimations of pressure drop across each cluster in these mostly limited-entry or extreme limited entry (XLE) completions. Additionally, near-wellbore (NWB) perf sealing pods are being used to divert treatments from initially open clusters to bypassed or partially open clusters in an attempt to force perf cluster efficiencies higher and distribute stimulation fluids and proppant more evenly. Having a consistent hole for every perforation is ideal in attempting to seal the perforations in the NWB region with a fixed diameter pod. SPE 189900 (Senters, et al 2018) provides more detail on diversion optimization. Engineered completions design is employed in an attempt to selectively perforate rock within a stage with similar mechanical properties to drive stimulated cluster efficiencies higher. Perforating similar rock with a consistent hole shaped charge only stands to improve the chances of distributing the treatment more evenly throughout the clusters. This paper will provide insight into the recent trends in perforating which show an increase in the amount of consistent hole shaped charges versus conventional shaped charges like deep penetrating and large hole. Diagnostic data accompanies entry hole diameter statistics and friction pressure calculations for the consistent hole shaped charges in order to demonstrate how they differ from conventional shaped charges. Finally, proppant tracer diagnostics will highlight several case studies where consistent hole shaped charges or other recent perforating methods were employed.

The generation of adaptive immune responses requires presentation of major histocompatibility (MHC) class II restricted immunogenic peptides to CD4 T cells by antigen presenting cells (APCs). These peptides are derived from the processing of protein antigens in acidic endosomal compartments. Classically, the generation of such peptides has been thought to have occurred through an exogenous pathway that involves internalization of antigens from the extracellular milieu. Recently, it has been demonstrated that peptides can also be generated from endogenously synthesized and retained antigen. While research in this field is burgeoning the physiological consequences of the processing of intracellular antigen are unknown. This dissertation examines the in vivo consequences and in vitro pathways relevant to the processing and presentation of antigen that is endogenously synthesized and retained in different intracellular compartments by B lymphocytes. I show that peptides derived from the processing of intracellular antigen are able to prime a CD4 T cell response irrespective of intracellular targeting. Furthermore, I show that T cells primed by peptides derived from antigen retained in the endoplasmic reticulum (ER) induce higher secretion of IFN-g and TNFa in responding cells. This increase is associated with upregulation of the ER stress responsive genes GADD34, Grp78 and CHOP, and down regulation of the costimulatory molecule OX40L in B lymphocytes. An OX40L reduced phenotype was recapitulated in CpG activated B lymphocytes by treatment with the ER stress inducing compounds tunicamycin and thapsigargin. I also show that presentation of ER retained antigen is linked to the ER associated degradation (ERAD) pathway. Presentation of the model antigen Ea from an ER targeted IgH requires mannose processing, cytosolic translocation and degradation by the resident cytosolic protease tripeptidyl peptidase II. Additionally, ER stress inducing compounds are able to initiate presentation of a secretory IgH that traffics through the ER but is not normally presented. Ultimately, the research presented here has far reaching implications for immune responses generated under states of cellular stress, such as viral infection oncogenic transformation and anti-idiotype responses at the levels of antigen processing and immune priming. These results reveal important considerations for vaccine design, as ER stress may serve an important adjuvant effect in the induction of cellular immunity

ObjectiveBeta radiation from nuclear weapons fallout could pose a risk of cutaneous radiation injury (CRI) to evacuating populations but has been investigated only cursorily. This work examines 2 components of CRI necessary for estimating the potential public health consequences of exposure to fallout: dose protraction and depth of dose.MethodsDose protraction for dry and moist desquamation was examined by adapting the biological effective dose (BED) calculation to a hazard function calculation similar to those recommended by the National Council on Radiation Protection and Measurements for other acute radiation injuries. Depth of burn was examined using Monte Carlo neutral Particle version 5 to model the penetration of beta radiation from fallout to different skin tissues.ResultsNonlinear least squares analysis of the BED calculation estimated the hazard function parameter θ1 (dose rate effectiveness factors) as 25.5 and 74.5 (Gy-eq)2 h−1 for dry and moist desquamation, respectively. Depth of dose models revealed that beta radiation is primarily absorbed in the dead skin layers and basal layer and that dose to underlying tissues is small (ConclusionsThe low relative dose to tissues below the basal layer suggests that radiation-induced necrosis or deep skin burns are unlikely from direct skin contamination with fallout. These results enable future modeling studies to better examine CRI risk and facilitate effectively managing and treating populations with specialized injuries from a nuclear detonation. (Disaster Med Public Health Preparedness. 2019;13:463-469)

The effects of surfactant and temperature on the spreading of a viscous droplet are studied. Lubrication theory is used to develop a model for the evolution of the droplet. The surfactant is assumed to be insoluble and transport onto and off of the droplet interface at the contact line is allowed. A linear temperature gradient plus a gradient in the surface energy are allowed along the substrate. We find that these effects together can increase the speed of the translation of the droplet. We also find that allowing the static contact angle to vary with the surfactant concentration and temperature, as described by Young’s law, can speed up droplet motion. When contact angle hysteresis is allowed, it is possible for the droplet to stop moving when surfactant transport is allowed along the interface.

We have undertaken a comprehensive spectroscopic survey of the Horologium-Reticulum supercluster (HRS) of galaxies. With a concentration on the intercluster regions, our goal is to resolve the "cosmic web" of filaments, voids, and sheets within the HRS and to examine the interrelationship between them. What are the constituents of the HRS? What can be understood about the formation of such a behemoth from these current constituents? More locally, are there small-scale imprints of the larger, surrounding environment, and can we relate the two with any confidence? What is the relationship between the HRS and the other superclusters in the nearby universe? These are the questions driving our inquiry. To answer them, we have obtained over 2500 galaxy redshifts in the direction of the intercluster regions in the HRS. Specifically, we have developed a sample of galaxies with a limiting brightness of betaJ < 17.5, which samples the galaxy luminosity function down to one magnitude below M? at the mean redshift of the HRS, z is approximately equal to 0.06. Exclusively, these intercluster redshifts were obtained with the six-degree field (6dF), multi-fiber spectrograph at the Anglo-Australian Observatory. In conjunction with the wide-field, 1.2m UK Schmidt, 6dF is the ideal supercluster observatory. Because it deploys the 150 fiber buttons over a 6-degree field, we are able to obtain coherent information over large areas of the sky, as is the case with a supercluster. In addition, we have obtained a complete sample of mean cluster redshifts and velocity dispersions for Abell clusters in the HRS using the Australian National University/2.3m, primarily. For most of the clusters, more than 10 galaxies were observed, and a reliable mean cluster redshift is determined. Furthermore, we have a near complete sample of bJ < 18.6 galaxies over a 4 degree × 4 degree region that encompasses several HRS clusters. With these datasets, we are able to "piece" together various structures over a large range of scales. We have also obtained high-resolution radio imaging over much of this smaller area. We find six void structures in the region with 10 less than or equal to RVOID less than or equal to 15 h-1 Mpc that are completely absent of 6dF galaxies (except for one void that contains a single galaxy down to our observational limits). To discover the voids, we implement the GyVe software tool that provides a 3-D, interactive visualization environment. Furthermore, four of these voids are embedded within the supercluster environment, while the other two are located at the observed boundaries of the HRS. This is reflected in the intrinsically different galaxy number counts profiles as a function of radius. The voids maintain their distinct profiles despite the fact that the 6dF sample is augmented with thousands of previously published redshifts. We also observe that matter (galaxies and clusters) is not distributed evenly around these voids, but seems to follow a highly ordered arrangement. Lastly, the intercluster regions (5-10 h-1 Mpc) within one of the most dense HRS volumes are examined. We define three different intercluster extensions varying in over-density from 20-60, which is 7-10 times the adjacent control volumes. Furthermore, we calculate a velocity dispersion of approximately 350 kms-1 within one intercluster filament approximately 11 h-1 Mpc in projected length. While varying in projected spatial width, the extended collection of intercluster galaxies joins the two richest complexes in the region. These galaxies also exhibit a preferred orientation of 60-90 degrees along its length. We further note that while some preferred orientations are found within smaller substructures, e.g., galaxy groups, these characterizations do not match the larger-scale galaxy distributions.