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The Open MPI for Exascale (OMPI-X) project was one of two in the Exascale Computing Project (ECP) focused on advancing the MPI ecosystem. The OMPI-X team worked with other MPI Forum members to champion several important features for inclusion in the MPI 4.0, 4.1, and upcoming 5.0 MPI standard versions, in support of the needs of exascale applications and systems. The team also worked with the larger Open MPI community to bring implementations of these new features and other enhancements into Open MPI, one of the leading open-source implementations of the MPI interface. This paper describes the motivation for the work of the OMPI-X project in the context of exascale computing needs, the nature of the resulting new capabilities in the MPI standard, and how they were implemented in the Open MPI library. Features include improved support for "MPI + X" programming models through partitioned communications and support for user-level threading, sessions, fault tolerance through the user-level fault mitigation (ULFM) and Reinit models, and other features. We also discuss enhancements to Open MPI providing improved performance and scalability for existing features, such as collective operations, one-sided operations, support for the Slingshot-11 interconnect of the initial exascale systems, and how the OMPI-X team worked to improve quality assurance for the Open MPI library, particularly on platforms of interest to the Department of Energy community. [ABSTRACT FROM AUTHOR]

Over the past few years, students by the thousands have refused to take their state's standardized tests. This "opt-out" phenomenon has prompted debate in state legislatures and in Washington, putting states at risk of losing Title I funds. Advocates describe opt-out as a grassroots movement of parents concerned about overtesting, teaching to the test, and a lack of transparency. Others oppose opt-out, viewing universal standardized testing as an important source of information for educators, students, and parents and a necessary tool for ensuring equity in public education. Scott Levy, a New York State public-school parent and local school board member, and Jonah Edelman, cofounder and CEO of Stand for Children, a national organization advocating for college and career readiness for all, draw different conclusions in their analyses of the topic.

Over the past few years, students by the thousands have refused to take their state's standardized tests. This 'opt-out' phenomenon has prompted debate in state legislatures and in Washington, putting [...]

Purpose: Delivering evidence-based tobacco dependence treatments to hospital patients in real-world settings continues to be a challenge. To achieve long-term abstinence, a program should provide both bedside counseling and post-discharge contacts. These program features are necessary but difficult to implement due to lack of training, time and low administrative support. The Rochester Model is a tobacco treatment program using existing staff and medical students to reduce the barriers for treating hospitalized smokers. Patients and Methods: Any smoking patient admitted to a participating hospital unit can participate. Staff nurses, mid-level providers and physicians deliver the counseling steps during the admission. Nurses hold two bedside counseling sessions, while providers give quitting advice and encourage pharmacotherapy. Nurses also contribute as unit champions and post-discharge call counselors. New York State quit line counselors combined with a University of Rochester call team fulfill the post-discharge calls. The latter call team is composed of staff nurses, respiratory therapists and medical students. Results: The number of smoking patients screened was 2610 while 385 enrolled after a proof-of-concept period. The 7-day point prevalence quit rates using the as treated (patients contacted) analysis is 50% at 4 weeks, 42% at 3 months and 38% at 6 months. The 7-day point prevalence quit rates using the intent-to-treat (all patients) analysis is 23% at 4 weeks, 16% at 3 months and 14% at 6 months. Conclusion: Preliminary data on the Rochester Model is showing an effective yet affordable tobacco treatment program using hospital staff and medical students. Nurses serve as bedside counselors, unit champions and post-discharge call counselors. Hospitals, even with limited resources, can implement tobacco treatment programs using existing staff. [ABSTRACT FROM AUTHOR]

Th cells are the major effector cells in transplant rejection and can be divided into Th1, Th2, Th17, and Treg subsets. Th differentiation is controlled by transcription factor expression, which is driven by positive and negative cytokine and chemokine stimuli at the time of T cell activation. Here we discovered that chemokine platelet factor 4 (PF4) is a negative regulator of Th17 differentiation. PF4-deficient and platelet-deficient mice had exaggerated immune responses to cardiac transplantation, including increased numbers of infiltrating Th17 cells and increased plasma IL-17. Although PF4 has been described as a platelet-specific molecule, we found that activated T cells also express PF4. Furthermore, bone marrow transplantation experiments revealed that T cell-derived PF4 contributes to a restriction in Th17 differentiation. Taken together, the results of this study demonstrate that PF4 is a key regulator of Th cell development that is necessary to limit Th17 differentiation. These data likely will impact our understanding of platelet-dependent regulation of T cell development, which is important in many diseases, in addition to transplantation., Introduction Platelets are the cellular mediator of thrombosis, but it is becoming increasingly evident that platelets actively participate in inflammation and immune responses (1-5). Platelets either initiate or accelerate the [...]

Relaxed synchronization offers the potential for maintaining application scalability, by allowing many processes to make independent progress when some processes suffer delays. Yet the benefits of this approach for important parallel workloads have not been investigated in detail. In this paper, we use a validated simulation approach to explore the noise-mitigation effects of idealized nonblocking collectives, in workloads where these collectives are a major contributor to total execution time. Although nonblocking collectives are unlikely to provide significant noise mitigation to applications in the low operating system noise environments expected in next-generation high-performance computing systems, we show that they can potentially improve application runtime with respect to other noise types. [ABSTRACT FROM AUTHOR]

The article reports that in order to deal with the growing health care costs in the U.S. the Affordable Care Act created the Center for Medicare and Medicaid Innovation (CMMI). It mentions that CMMI was meant to be the U.S. government's innovation laboratory for health care. It states that Tom Price, Health and Human Services (HHS) Secretary of the U.S. President Donald Trump, paused the Obama-era mandatory bundled-payment programs.

Building the next-generation of extreme-scale distributed systems will require overcoming several challenges related to system resilience. As the number of processors in these systems grow, the failure rate increases proportionally. One of the most common sources of failure in large-scale systems is memory. In this paper, we propose a novel runtime for transparently exploiting memory content similarity to improve system resilience by reducing the rate at which memory errors lead to node failure. We evaluate the viability of this approach by examining memory snapshots collected from eight high-performance computing (HPC) applications and two important HPC operating systems. Based on the characteristics of the similarity uncovered, we conclude that our proposed approach shows promise for addressing system resilience in large-scale systems. [ABSTRACT FROM AUTHOR]

This article aims to provide a more comprehensive overview of the Narcotics Eviction Program (NEP), an effort initiated by Manhattan's District Attorney Robert Morgenthau in 1988 to stem the tide of the crack cocaine epidemic in New York City, and reframe and expand the legal and policy debate to include an understanding of this dynamic feedback mechanism. It looks at the institutional, procedural, and doctrinal structure of the NEP in light of the traditional crime prevention/tenants' rights dichotomy. It argues that the program fails to perform this balancing act adequately because the mechanisms in place to protect the interests of innocent tenants are unreliable and insufficient. The article analyzes the NEP through the lens of social organization theory.

Measurement of recirculation and intradialytic venous line pressures may aid in the detection of hemodialysis vascular access stenoses. The authors screened 29 consecutive asymptomatic patients for recirculation values exceeding 15% or venous pressures greater than ISO mmHg. All 13 patients requiring and agreeing to angiography on the basis of the screening protocol proved to have high-grade stenoses of their vascular access outflow or inflow. Asymptomatic vascular access pathology is common. High-risk asymptomatic populations may be detected by simple screening procedures. [ABSTRACT FROM AUTHOR]

Summary: Coordinated checkpoint/restart is currently the dominant approach to mitigating the impact of failures on important scientific applications running on large‐scale distributed systems. However, there is widespread evidence that coordinated checkpointing may no longer be viable on next‐generation systems. Uncoordinated checkpoint/restart attempts to address the shortcomings of coordinated checkpoint/restart by allowing application processes to checkpoint their state independently. However, eliminating coordination may significantly degrade application performance. In this paper, we propose an approach that leverages existing coordination in important scientific applications to approximately coordinate checkpoints. Specifically, we propose to extend MPI implementations to force checkpoints to occur immediately after the completion of a collective operation. We evaluate the performance implications of this approach using an existing validated simulation framework. Our results demonstrate that approximately coordinated checkpointing can significantly improve application performance relative to totally uncoordinated checkpointing. We also show that forcing checkpoints to occur following a collective operation has a small impact on the nominal checkpoint interval for several important workloads. As a whole, the results presented in this paper demonstrate that approximately coordinated checkpointing may provide significant performance benefits without significantly increasing the cost of failure recovery. [ABSTRACT FROM AUTHOR]

Summary: This paper explores key differences of MPI match lists for several important United States Department of Energy (DOE) applications and proxy applications. This understanding is critical in determining the most promising hardware matching design for any given high‐speed network. The results of MPI match list studies for the major open‐source MPI implementations, MPICH and Open MPI, are presented, and we modify an MPI simulator, LogGOPSim, to provide match list statistics. These results are discussed in the context of several different potential design approaches to MPI matching–capable hardware. The data illustrate the requirements for different hardware designs in terms of performance and memory capacity. This paper's contributions are the collection and analysis of data to help inform hardware designers of common MPI requirements and highlight the difficulties in determining these requirements by only examining a single MPI implementation. [ABSTRACT FROM AUTHOR]

Th cells are the major effector cells in transplant rejection and can be divided into Th1, Th2, Th17, and Treg subsets. Th differentiation is controlled by transcription factor expression, which is driven by positive and negative cytokine and chemokine stimuli at the time of T cell activation. Here we discovered that chemokine platelet factor 4 (PF4) is a negative regulator of Th17 differentiation. PF4-deficient and platelet-deficient mice had exaggerated immune responses to cardiac transplantation, including increased numbers of infiltrating Th17 cells and increased plasma IL-17. Although PF4 has been described as a platelet-specific molecule, we found that activated T cells also express PF4. Furthermore, bone marrow transplantation experiments revealed that T cell-derived PF4 contributes to a restriction in Th17 differentiation. Taken together, the results of this study demonstrate that PF4 is a key regulator of Th cell development that is necessary to limit Th17 differentiation. These data likely will impact our understanding of platelet-dependent regulation of T cell development which is important in many diseases, in addition to transplantation. [ABSTRACT FROM AUTHOR]

Background: A limitation of diffusion tensor imaging (DTI)-based tractography is peritumoral edema that confounds traditional diffusion-based magnetic resonance metrics., Objective: To augment fiber-tracking through peritumoral regions by performing novel edema correction on clinically feasible DTI acquisitions and assess the accuracy of the fiber-tracks using intraoperative stimulation mapping (ISM), task-based functional magnetic resonance imaging (fMRI) activation maps, and postoperative follow-up as reference standards., Methods: Edema correction, using our bi-compartment free water modeling algorithm (FERNET), was performed on clinically acquired DTI data from a cohort of 10 patients presenting with suspected high-grade glioma and peritumoral edema in proximity to and/or infiltrating language or motor pathways. Deterministic fiber-tracking was then performed on the corrected and uncorrected DTI to identify tracts pertaining to the eloquent region involved (language or motor). Tracking results were compared visually and quantitatively using mean fiber count, voxel count, and mean fiber length. The tracts through the edematous region were verified based on overlay with the corresponding motor or language task-based fMRI activation maps and intraoperative ISM points, as well as at time points after surgery when peritumoral edema had subsided., Results: Volume and number of fibers increased with application of edema correction; concordantly, mean fractional anisotropy decreased. Overlay with functional activation maps and ISM-verified eloquence of the increased fibers. Comparison with postsurgical follow-up scans with lower edema further confirmed the accuracy of the tracts., Conclusion: This method of edema correction can be applied to standard clinical DTI to improve visualization of motor and language tracts in patients with glioma-associated peritumoral edema., (© Congress of Neurological Surgeons 2021.)

Purpose: The clinical utility of plasma cell-free DNA (cfDNA) has not been assessed prospectively in patients with glioblastoma (GBM). We aimed to determine the prognostic impact of plasma cfDNA in GBM, as well as its role as a surrogate of tumor burden and substrate for next-generation sequencing (NGS)., Experimental Design: We conducted a prospective cohort study of 42 patients with newly diagnosed GBM. Plasma cfDNA was quantified at baseline prior to initial tumor resection and longitudinally during chemoradiotherapy. Plasma cfDNA was assessed for its association with progression-free survival (PFS) and overall survival (OS), correlated with radiographic tumor burden, and subjected to a targeted NGS panel., Results: Prior to initial surgery, GBM patients had higher plasma cfDNA concentration than age-matched healthy controls (mean 13.4 vs. 6.7 ng/mL, P < 0.001). Plasma cfDNA concentration was correlated with radiographic tumor burden on patients' first post-radiation magnetic resonance imaging scan (ρ = 0.77, P = 0.003) and tended to rise prior to or concurrently with radiographic tumor progression. Preoperative plasma cfDNA concentration above the mean (>13.4 ng/mL) was associated with inferior PFS (median 4.9 vs. 9.5 months, P = 0.038). Detection of ≥1 somatic mutation in plasma cfDNA occurred in 55% of patients and was associated with nonstatistically significant decreases in PFS (median 6.0 vs. 8.7 months, P = 0.093) and OS (median 5.5 vs. 9.2 months, P = 0.053)., Conclusions: Plasma cfDNA may be an effective prognostic tool and surrogate of tumor burden in newly diagnosed GBM. Detection of somatic alterations in plasma is feasible when samples are obtained prior to initial surgical resection., (©2019 American Association for Cancer Research.)