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Assimilation of country rock xenoliths by the host kimberlite can result in the development of concentric reaction zones within the xenoliths and a reaction halo in the surrounding contaminated kimberlite. Petrographic and geochemical changes across the reaction zones in the xenoliths and the host kimberlite were studied using samples with different kimberlite textures and contrasting xenolith abundances from the Renard 65 kimberlite pipe. The pipe, infilled by Kimberley-type pyroclastic (KPK) and hypabyssal kimberlite (HK) and kimberlite with transitional textures, was emplaced into granitoid and gneisses of the Superior Craton. Using samples of zoned, medium-sized xenoliths of both types, mineralogical and geochemical data were collected across xenolith-to-kimberlite profiles and contrasted with those of fresh unreacted country rock and hypabyssal kimberlite. The original mineralogy of the unreacted xenoliths (potassium feldspar-plagioclase-quartz-biotite in granitoid and plagioclase-quartz-biotite-orthopyroxene in gneiss) is replaced by prehnite, pectolite, and diopside. In the kimberlite halo, olivine is completely serpentinized and diopside and late phlogopite crystallized in the groundmass. The xenoliths show the progressive degrees of reaction, textural modification, and mineral replacement in the sequence of kimberlite units KPK — transitional KPK — transitional HK. The higher degree of reaction observed in the HK-hosted xenoliths as compared to the KPK-hosted xenoliths in this study and elsewhere may partly relate to higher temperatures in xenoliths included in an HK melt. The correlation between the degree of reaction and the kimberlite textures suggests that the reactions are specific to and occur within each emplaced batch of magma and cannot result from external post-emplacement processes that should obliterate the textural differences across the kimberlite units. Xenolith assimilation may have started in the melt, as suggested by the textures in the xenoliths and the surrounding halos and proceeded in the subsolidus. Elevated CaO at the kimberlite-xenolith contact appears to be an important factor in producing the concentric mineralogical zoning in assimilated xenoliths.

Renard 65, a diamondiferous pipe in the Neoproterozoic Renard kimberlite cluster (Quebec, Canada), is a steeply-dipping and downward-tapering diatreme comprised of three pipe-filling units: kimb65a, kimb65b, and kimb65d. The pipe is surrounded by a marginal and variably-brecciated country rock aureole and is crosscut by numerous hypabyssal dykes: kimb65c. Extensive petrographic and mineralogical characterization of over 700 m of drill core from four separate drill holes, suggests that Renard 65 is a Group I kimberlite, mineralogically classified as phlogopite kimberlite and serpentine-phlogopite kimberlite. Kimb65a is a massive volcaniclastic kimberlite dominated by lithic clasts, magmaclasts, and discrete olivine macrocrysts, hosted within a fine-grained diopside and serpentine-rich matrix. Kimb65b is massive, macrocrystic, coherent kimberlite with a groundmass assemblage of phlogopite, spinel, perovskite, apatite, calcite, serpentine and rare monticellite. Kimb65c is a massive, macrocrystic, hypabyssal kimberlite with a groundmass assemblage of phlogopite, serpentine, calcite, perovskite, spinel, and apatite. Kimb65d is massive volcaniclastic kimberlite with localized textures that are intermediate between volcaniclastic and coherent, with tightly packed magmaclasts separated by a diopside- and serpentine-rich matrix. Lithic clasts of granite-gneiss in kimb65a are weakly reacted, with partial melting of feldspars and crystallization of richterite and actinolite. Lithic clasts in kimb65b and kimb65d are entirely recrystallized to calcite + serpentine/chlorite + pectolite and display inner coronas of diopside-aegirine and an outer corona of phlogopite. Compositions are reported for all minerals in the groundmass of coherent kimberlites, magmaclasts, interclast matrices, and reacted lithic clasts. The Renard 65 rocks are texturally classified as Kimberley-type pyroclastic kimberlites and display transitional textures. The kimberlite units are interpreted to have formed in three melt batches based on their distinct spinel chemistry: kimb65a, kimb65b and kimb65d. We note a strong correlation between the modal abundances of lithic clasts and the textures of the kimberlites, where increasing modal abundances of granite/gneiss are observed in kimberlites with increasingly fragmental textures.

We evaluated the strengths and weaknesses of Intel extensions to HTM - TSX.We described features that are likely to yield performance gains when using TSX.We explored with the aid of a new tool called htm-pBuilder the performance of TSX.We introduced a efficient policy for guaranteeing forward progress on top of TSX.We explored various fall-back policy tunings and transaction properties of TSX. This paper presents an extensive performance study of the implementation of Hardware Transactional Memory (HTM) in the Haswell generation of Intel x86 core processors. It evaluates the strengths and weaknesses of this new architecture by exploring several dimensions in the space of Transactional Memory (TM) application characteristics using the Eigenbench?(Hong et?al., 2010 1) and the CLOMP-TM?(Schindewolf et?al., 2012 2), benchmarks. This paper also introduces a new tool, called htm-pBuilder that tailors fallback policies and allows independent exploration of its parameters.This detailed performance study provides insights on the constraints imposed by the Intel's Transaction Synchronization Extension (Intel's TSX) and introduces a simple, but efficient policy for guaranteeing forward progress on top of the best-effort Intel's HTM which was critical to achieving performance. The evaluation also shows that there are a number of potential improvements for designers of TM applications and software systems that use Intel's TM and provides recommendations to extract maximum benefit from the current TM support available in Haswell.

Eclipse OMR is an open-source C++ framework for building robust language runtimes. The OMR toolkit includes a dynamic Just-In-Time (JIT) compiler, a garbage collector, a platform abstraction library, and a set of developer tooling capabilities. To support the diverse languages and architectures targeted by the framework, OMR's variability implementation uses a combination of build-system variability and static polymorphism. That is, all implementation classes that depend on the selected language and architecture are decided at compile time. However, OMR developers now realize that the current variability design decision, specifically the static polymorphism implementation, has its drawbacks. They are considering using dynamic polymorphism instead of static polymorphism. Before making such a fundamental design change, however, it is crucial to collect function information and overload/override statistics about the current variability in the code base.In this paper, we present OMRStatistics, a static analysis tool that we built for OMR developers to help them collect this information. Specifically, OMRStatistics (1) visualizes the class hierarchy from OMR's current static polymorphic implementation, (2) visualizes the function overloads and overrides with their respective locations in the source code, (3) collects important information about the classes and functions, and (4) stores all the collected information in a database for further analysis. Our tool OMRStatistics allows OMR developers to make better design decisions on which variability extension points should be switched from static polymorphism to dynamic polymorphism.

This paper describes an end-to-end system implementation of a transactional memory (TM) programming model on top of the hardware transactional memory (HTM) of the Blue Gene/Q machine. The TM programming model supports most C/C++ programming constructs using a best-effort HTM and the help of a complete software stack including the compiler, the kernel, and the TM runtime. An extensive evaluation of the STAMP and the RMS-TM benchmark suites on BG/Q is the first of its kind in understanding characteristics of running TM workloads on real hardware TM. The study reveals several interesting insights on the overhead and the scalability of BG/Q HTM with respect to sequential execution, coarse-grain locking, and software TM.

From 1990-2005 at Ochsner Medical Center in New Orleans, LA, cardiopulmonary bypass (CPB) was used only when necessary during lung transplantation surgeries. Ochsner's lung transplant program was closed for more than 4 years after Hurricane Katrina, and since the program's reestablishment in 2010, the majority of lung transplantation surgeries have been performed with the patient on CPB and with a median sternotomy incision. The purpose of this study was to compare the outcomes of the CPB and non-CPB groups.After institutional review board approval, we conducted a retrospective review of the entire program using the Ochsner lung transplant database to identify patients in the non-CPB group from 1990-2005 and in the CPB group from 2010-2014. We calculated 1- and 3-year survival rates for each patient and reviewed medical records for evidence of stroke, the need for operative reexploration, and venous stenosis. We also performed a subgroup analysis of the first 20 consecutive patients undergoing lung transplantation on CPB with median sternotomy from February 2010 through April 2011 to examine intraoperative blood product use, the quantity of blood products administered, CPB cannulation and pump complications, ischemic time, and primary graft dysfunction.Of the 208 patients in the non-CPB group, 74% had 1-year graft survival and 55% had 3-year survival following transplantation. After February 2010, 79 patients underwent lung transplantation on CPB with median sternotomy, and 90% of those patients had 1-year graft survival. Of the 46 patients available for 3-year follow-up, 59% were alive with functional grafts. The difference in 1-year survival rates between the 2 cohorts was statistically significant. Two deaths, 3 strokes, and 5 reexplorations of the chest for bleeding occurred during the perioperative time period in the CPB group, but no mortality was associated with these perioperative events. One patient who had perioperative complications died within the first year; the death was attributable to gastric perforation.Patients' early outcomes appear to have improved with the use of CPB and median sternotomy; however, 3-year survival is similar to the non-CPB group. Technical benefits of CPB with median sternotomy include decreased warm ischemia time during graft implantation, controlled hemodynamics and reperfusion, avoidance of single-lung ventilation of a freshly implanted graft, and the option to open the left atrium for implantation of a venous cuff without using a clamp. The surgical exposure facilitated by CPB with median sternotomy for lung transplantation appears to be a safe and feasible approach for lung transplantations.

Traumatic blunt cerebrovascular injury (BCVI) may portend catastrophic complications if untreated. Who should be screened for BCVI is controversial. The purpose of this study was to develop and validate a prediction score (pBCVI) to identify those at sufficient risk to warrant dedicated screening.We conducted a cohort study using data for years 2002-2007 from the National Trauma Data Bank. Blunt trauma patients aged 16 years and older were randomly divided into two groups for score creation and validation. Final prediction model included age, sex, Trauma Mortality Prediction Model p(death), traumatic intracranial hemorrhage, cerebellar/brain stem injury, malar/maxillary fracture, mandible fracture, cervical spine fracture, cervical spinal cord injury, thoracic spinal cord injury, and chest Abbreviated Injury Scale ≥3. pBCVI was evaluated using receiver operating characteristic curve area and the Hosmer-Lemeshow statistic. The Youden Index estimated an optimal cut-point (J) of the pBCVI.The cohort numbered 1,398,310 patients, including 2,125 with BCVI. The overall incidence of BCVI was 0.15%. Cervical spine fracture had the strongest association with BCVI (odds ratio 4.82, p0.001). The receiver operating characteristic curve for pBCVI was 0.93 and the Hosmer-Lemeshow statistic was 206.3, p0.01. The optimal cut-point (J) of pBCVI was 0.0013 (sensitivity 0.91, specificity 0.82) and would miss 186 (8.8%) injuries in our cohort. To identify all BCVI using this model, an unrealistic 96% of the cohort would require screening.A model based on a pattern of other injuries cannot be used as a stand-alone instrument to determine screening for BCVI. "Optimal" model cut-points are not ideal for all injuries. Clinical suspicion that integrates energy of mechanism and associated injuries remains essential to effectively screen for BCVI and minimize patient risk for a catastrophic missed injury.

Most studies of Best-Effort HTM (BE-HTM) performance use a single serialization manager and a single parameter value across all benchmarks, inputs and thread counts. The experimental study in this paper indicates that the values chosen for serialization-manager parameters have a significant effect on performance in the Blue Gene/Q's (BG/Q) BE-HTM system. Moreover, for a given serialization manager, different benchmarks typically require different parameter values to achieve the best performance. BG/Q features two TM settings that represent two different HTM designs. A study of these two settings indicate that serialization-management decisions are also sensitive to changes in the HTM design. Therefore the choice of serialization management, including the tuning parameters, should be reevaluated for each new platform because effectiveness is affected even by relatively small changes to the HTM design.

Transactional Memory (TM) is a new programming paradigm for both simple concurrent programming and high concurrent performance. Hardware Transactional Memory (HTM) is hardware support for TM-based programming. It has lower overhead than software transactional memory (STM), which is a software-based implementation of TM. There are now four commercial systems, IBM Blue Gene/Q, IBM zEnterprise EC12, Intel Core, and IBM POWER8, offering HTM. Our work is the first to compare the performance of these four HTM systems. We measured the STAMP benchmarks, the most widely used TM benchmarks. We also evaluated the specific features of each HTM system. Our experimental results show that: (1) there is no single HTM system that is more scalable than the others in all of the benchmarks, (2) there are measurable performance differences among the HTM systems in some benchmarks, and (3) each HTM system has its own implementation characteristics that limit its scalability.

The primary goal of this research is to identify and examine the components of responsible drinking advertisements. We will examine industry and government related advertisements as we try to understand one of our major questions: does the source influence the validity of the message? The next group of major questions that we will be looking to answer is how are the vague quantifiers used in responsible drinking campaigns interpreted by the public? How many drinks do people consider “too much?” What does “drink responsibly” really mean? The third major question is whether or not an individual’s current consumption patterns of alcohol have any effect on how individuals assess responsible drinking campaigns. Our qualitative research has indicated that social influences can be strongly related with drinking patterns; this will be further examined in our quantitative research. Also, we will be looking into some of the psychology behind industry and government sponsored advertisements as well as gathering and interpreting information from a sample of our target demographic. Our target demographic consists of both male and females between the ages 18-24. Our literature review and qualitative analysis gave us good insight into some of the potential answers to our questions. We will use these potential answers from our previous research to guide us as we attempt to conduct conclusive research based on a sample data of 169 individuals. Our findings will aid us in developing conclusions and recommendations for Alberta Health Services.

This paper presents an extensive performance study of the implementation of Hardware Transactional Memory (HTM) in the Haswell generation of Intel x86 core processors. This study evaluates the strengths and weaknesses of this new architecture exploring several dimensions in the space of Transactional Memory (TM) application characteristics using the Eigenbench [1] and the CLOMP-TM [2] benchmarks. This detailed performance study provides insights on the constraints imposed by the Intel's Transaction Synchronization Extension (Intel's TSX) and introduces a simple, but efficient policy for guaranteeing forward progress on top of the besteffort Intel's HTM and also was critical to achieving performance. The evaluation also shows that there are a number of potential improvements for designers of TM applications and software systems that use Intel's TM and provides recommendations to extract maximum benefit from the current TM support available in Haswell.

Outlier detection and ensemble learning are well established research directions in data mining yet the application of ensemble techniques to outlier detection has been rarely studied. Here, we propose and study subsampling as a technique to induce diversity among individual outlier detectors. We show analytically and experimentally that an outlier detector based on a subsample per se, besides inducing diversity, can, under certain conditions, already improve upon the results of the same outlier detector on the complete dataset. Building an ensemble on top of several subsamples is further improving the results. While in the literature so far the intuition that ensembles improve over single outlier detectors has just been transferred from the classification literature, here we also justify analytically why ensembles are also expected to work in the unsupervised area of outlier detection. As a side effect, running an ensemble of several outlier detectors on subsamples of the dataset is more efficient than ensembles based on other means of introducing diversity and, depending on the sample rate and the size of the ensemble, can be even more efficient than just the single outlier detector on the complete data.

Blue Gene/Q's (BG/Q) unique transactional memory system provides hardware isolation, atomicity and consistency for memory locations while leaving the details of the transactional programming system to software layers above the hardware [3]. This design allows for complex systems implemented as part of the software runtime. Here a profiling extension to the software runtime is presented.

This paper describes an end-to-end system implementation of the transactional memory (TM) programming model on top of the hardware transactional memory (HTM) of the Blue Gene/Q (BG/Q) machine. The TM programming model supports most C/C++ programming constructs on top of a best-effort HTM with the help of a complete software stack including the compiler, the kernel, and the TM runtime. An extensive evaluation of the STAMP benchmarks on BG/Q is the first of its kind in understanding characteristics of running coarse-grained TM workloads on HTMs. The study reveals several interesting insights on the overhead and the scalability of BG/Q HTM with respect to sequential execution, coarse-grain locking, and software TM.