The Pan-STARRS Moving Object Processing System

We describe the Pan-STARRS Moving Object Processing System (MOPS), a modern software package that produces automatic asteroid discoveries and identifications from catalogs of transient detections from next-generation astronomical survey telescopes. MOPS achieves >99.5% efficiency in producing orbits from a synthetic but realistic population of asteroids whose measurements were simulated for a Pan-STARRS4-class telescope. Additionally, using a nonphysical grid population, we demonstrate that MOPS can detect populations of currently unknown objects such as interstellar asteroids. MOPS has been adapted successfully to the prototype Pan-STARRS1 telescope despite differences in expected false detection rates, fill-factor loss, and relatively sparse observing cadence compared to a hypothetical Pan-STARRS4 telescope and survey. MOPS remains highly efficient at detecting objects but drops to 80% efficiency at producing orbits. This loss is primarily due to configurable MOPS processing limits that are not yet tuned for the Pan-STARRS1 mission. The core MOPS software package is the product of more than 15 person-years of software development and incorporates countless additional years of effort in third-party software to perform lower-level functions such as spatial searching or orbit determination. We describe the high-level design of MOPS and essential subcomponents, the suitability of MOPS for other survey programs, and suggest a road map for future MOPS development.

Deterministic Scale-Free Pipeline Parallelism with Hyperqueues

Ubiquitous parallel computing aims to make parallel programming accessible to a wide variety of programming areas using deterministic and scale-free programming models built on a task abstraction. However, it remains hard to reconcile these attributes with pipeline parallelism, where the number of pipeline stages is typically hard-coded in the program and defines the degree of parallelism.

This paper introduces hyperqueues, a programming abstraction that enables the construction of deterministic and scale-free pipeline parallel programs. Hyperqueues extend the concept of Cilk++ hyperobjects to provide thread-local views on a shared data structure. While hyperobjects are organized around private local views, hyperqueues require shared concurrent views on the underlying data structure. We define the semantics of hyperqueues and describe their implementation in a work-stealing scheduler. We demonstrate scalable performance on pipeline-parallel PARSEC benchmarks and find that hyperqueues provide comparable or up to 30% better performance than POSIX threads and Intel's Threading Building Blocks. The latter are highly tuned to the number of available processing cores, while programs using hyperqueues are scale-free.

The role of SOCS3/pSTAT3 pathway in the development of diabetic retinopathy

Purpose: Suppressor of cytokine signalling (SOCS) proteins are feedback inhibitors of the JAK/STAT pathway. SOCS3 critically controls STAT3 activation, cytokine signalling and inflammatory gene expression in macrophages and microglia. In this study, we investigated the role of SOCS3/STAT3 in myeloid cells in the initiation and progression of diabetic retinopathy (DR). 
Methods: Mice with a conditional deletion of SOCS3 in myeloid cells (LysMCre-SOCS3 fl/fl) and C57BL/6J (as control) were rendered diabetic by a low-dose multiple intraperitoneal injections of Stroptozocine. Diabetes related retinal changes, including leukostasis, acellular capilliaries, and microglial activation were assessed at different stages of disease. Bone marrow derived macrophages (BMDMs) from LysMCreSOCS3 fl/fl and C57BL/6J mice were cultured in high glucose (HG) medium, and cell activation was evaluated by real-time RT-PCR.
Results: In C57BL/6J diabetic mice the expression of phosphorylated STAT3 (pSTAT3) was increased and SOCS3 was decreased in the retina. Interleukin 6 (IL-6), the main cytokine that stimulates STAT3 activation, was increased in the plamsa in diabetic mice. Although blood glucose levels and Hbac-1 were comparable between LysMCre-SOCS3fl/fl and WT mice after STZ injection, the LysMCreSOCS3 fl/fl diabetic mice developed severe retinal vasculopathy, including increased leukostasis and microglial activation at one month and enhanced acellular capillary formation at 6 months after diabetes induction. 
Conclusions: our study suggests that the JAK/STAT3 pathway is involved in the initiation and progression of DR, and uncontrolled STAT3 activation results in accelerated DR progression. Targeting the STAT3 pathway may be a novel approach for the management of DR.

Special condition wind power forecasting based on Gaussian process and similar historical data

Due to the variability of wind power, it is imperative to accurately and timely forecast the wind generation to enhance the flexibility and reliability of the operation and control of real-time power. Special events such as ramps, spikes are hard to predict with traditional methods using solely recently measured data. In this paper, a new Gaussian Process model with hybrid training data taken from both the local time and historic dataset is proposed and applied to make short-term predictions from 10 minutes to one hour ahead. A key idea is that the similar pattern data in history are properly selected and embedded in Gaussian Process model to make predictions. The results of the proposed algorithms are compared to those of standard Gaussian Process model and the persistence model. It is shown that the proposed method not only reduces magnitude error but also phase error.

What do high penetrations of wind power mean for gas generation?

Dependency on thermal generation and continued wind power growth in Europe due to renewable energy and greenhouse gas emissions targets has resulted in an interesting set of challenges for power systems. The variability of wind power impacts dispatch and balancing by grid operators, power plant operations by generating companies and market wholesale costs. This paper quantifies the effects of high wind power penetration on power systems with a dependency on gas generation using a realistic unit commitment and economic dispatch model. The test system is analyzed under two scenarios, with and without wind, over one year. The key finding of this preliminary study is that despite increased ramping requirements in the wind scenario, the unit cost of electricity due to sub-optimal operation of gas generators does not show substantial deviation from the no wind scenario.