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Exascale computing systems will exhibit high degrees of hierarchical parallelism, with thousands of computing nodes and hundreds of cores per node. Efficiently exploiting hierarchical parallelism is challenging due to load imbalance that arises at multiple levels. OpenMP is the most widely-used standard for expressing and exploiting the ever-increasing node-level parallelism. The scheduling options in OpenMP are insufficient to address the load imbalance that arises during the execution of multithreaded applications. The limited scheduling options in OpenMP hinder research on novel scheduling techniques which require comparison with others from the literature. This work introduces LB4OMP, an open-source dynamic load balancing library that implements successful scheduling algorithms from the literature. LB4OMP is a research infrastructure designed to spur and support present and future scheduling research, for the benefit of multithreaded applications performance. Through an extensive performance analysis campaign, we assess the effectiveness and demystify the performance of all loop scheduling techniques in the library. We show that, for numerous applications-systems pairs, the scheduling techniques in LB4OMP outperform the scheduling options in OpenMP. Node-level load balancing using LB4OMP leads to reduced cross-node load imbalance and to improved MPI+OpenMP applications performance, which is critical for Exascale computing. [ABSTRACT FROM AUTHOR]

Abstract.  In termites, the soldiers’ sex ratio is often biased toward one sex. Unlike in the Hymenoptera, this bias cannot easily be explained by relatedness asymmetries because termites are diploid. Matsuura proposed that when large body size is adaptive for colony defence (e.g. in case of phragmotic defence) then the larger sex (given sexual size dimorphism exists) should be more likely to reach a threshold size and develop into soldiers. This would explain biased sex ratios. Matsuura validated his hypothesis for four Reticulitermes species. Here, we tested his hypothesis for two species of Cryptotermes with phragmotic defence. These drywood termites have a life type that is thought to be ancestral in termite’s evolution, thus giving us potential insights into the evolution of the soldier caste. In one of these species, the sex ratio of soldiers was highly female biased, but we could not support Matsuura’s hypothesis. Both species lacked sexual size dimorphism in all castes. Additionally, in both species, the sex ratio of helpers and sexuals did not deviate from a 1:1 ratio, and hence can also not account for the bias observed in soldiers. However, this study showed that there were behavioural differences between the sexes in both species, which could shed some light on biased sex ratio in soldiers. Our findings also indicate that the developmental pathway taken by individuals reflects a ‘decision’ at the colony level. The discovery of behavioural differences between sexes in termites should open the way to similar studies in other taxa with helpers/ workers of both sexes, as it might reveal more task partitioning in colonies than previously thought and it raises questions concerning the selective pressures that acted on caste evolution in termites. [ABSTRACT FROM AUTHOR]

Antigen-specific vaccines are one of several molecularly targeted approaches under investigation as possible treatments for prostate cancer. Important to the development of vaccines is the identification of appropriate target antigens. We hypothesized that antigens of the prostate might be identified in patients with the chronic prostatitis/pelvic pain syndrome, a syndrome for which an autoimmune pathology has been proposed. Such antigens might represent naturally recognized target antigens of the prostate that could be investigated in the future as prostate tumor antigens. In this report, we used SEREX to identify proteins expressed in a prostate cDNA expression library recognized by IgG from the sera of patients with chronic prostatitis. Candidate proteins were evaluated using a panel of sera from 62 subjects with symptomatic prostatitis and 71 control male blood donors. We identified one protein that was recognized primarily in sera from subjects with prostatitis compared with controls. MAD-PRO-34, a nucleolar autoantigen, was recognized in 6/62 subjects and 0/71 controls (p = 0.00897). This protein had previously been identified as an autoantigen in patients with prostate cancer. In addition, the NY-CO-7 protein was recognized in 9/62 subjects and 3/71 controls (p = 0.0654). Two subjects had IgG specific for both the MAD-PRO-34 and NY-CO-7 gene products. Our results demonstrate that some patients with the chronic prostatitis/pelvic pain syndrome have autoantibodies to specific proteins. Proteins identified, and MAD-PRO-34 in particular, could be further investigated as potential prostate tumor antigens. [ABSTRACT FROM AUTHOR]

Specific removal of the sentinel lymph node (SLN) during breast cancer surgery presents physicians with the opportunity to detect early metastatic disease. To increase the accuracy of intraoperative SLN detection, new methods with higher sensitivity and specificity are required. We have quantitatively compared conventional preoperative lymphoscintigraphy with albumin radiocolloids (99mTc-NanoColl) with optical intraoperative guidance using the near infrared dye indocyanine green (ICG) in an orthotopic mouse model for metastatic breast cancer. Furthermore, we have applied a self-assembled multimodal complex, in which ICG is non-covalently bound to the albumin radiocolloid, to attain identical dynamics of the radioactive and optical components. The SLN specificity of the multimodal complex is similar to conventional lymphoscintigraphy, while the fluorescent signal-to-noise ratio is improved by 86% compared to ICG alone. In addition, the multimodal complex permits scintigraphic validation of the fluorescent findings. The multimodal ICG-99mTc-NanoColl complex can be used both for lymphoscintigraphy by preoperative single photon emission computed tomography/computed tomography and for surgical navigation by intraoperative fluorescence imaging. [ABSTRACT FROM AUTHOR]

The derivation of the correct functional form of source terms in plasma fluid theory is revisited. The relation between the fluid source terms and atomic physics differential cross sections is established for particle-impact ionization. It is shown that the interface between atomic and plasma physics is completely described by three scalar functions of the incident particle energy. These are the total cross section and the newly introduced forward momentum and energy functions, which are properties of the differential cross sections only. For electron-impact ionization, the binary-encounter-Bethe (BEB) and binary-encounter-dipole (BED) models (Kim and Rudd 1994 Phys. Rev. A 50 3954) are used to calculate these functions analytically, yielding expressions that both accurately capture the physics and can be efficiently evaluated within fluid simulation codes. The source terms explain the observed electron temperature regimes in a wide variety of basic plasma physics experiments, including the trends across different gases. [ABSTRACT FROM AUTHOR]