FPGA-accelerated group-by aggregation using synchronizing caches

Recent trends in hardware have dramatically dropped the price of RAM and shifted focus from systems operating on disk-resident data to in-memory solutions. In this environment high memory access latency, also known as memory wall, becomes the biggest data processing bottleneck. Traditional CPU-based architectures solved this problem by introducing large cache hierarchies. However algorithms which experience poor locality can limit the benefits of caching. In turn, hardware multithreading provides a generic solution that does not rely on algorithm-specific locality properties. In this paper we present an FPGA-accelerated implementation of in-memory group-by hash aggregation. Our design relies on hardware multithreading to efficiently mask long memory access latency by implementing a custom operation datapath on FPGA. We propose using CAMs (Content Addressable Memories) as a mechanism of synchronization and local pre-aggregation. To the best of our knowledge this is the first work, which uses CAMs as a synchronizing cache. We evaluate aggregation throughput against the state-of-the-art multithreaded software implementations and demonstrate that the FPGA-accelerated approach significantly outperforms them on large grouping key cardinalities and yields speedup up to 10x

A Comprehensive Classification and Evolutionary Analysis of Plant Homeobox Genes

The full complement of homeobox transcription factor sequences, including genes and pseudogenes, was determined from the analysis of 10 complete genomes from flowering plants, moss, Selaginella, unicellular green algae, and red algae. Our exhaustive genome-wide searches resulted in the discovery in each class of a greater number of homeobox genes than previously reported. All homeobox genes can be unambiguously classified by sequence evolutionary analysis into 14 distinct classes also characterized by conserved intron–exon structure and by unique codomain architectures. We identified many new genes belonging to previously defined classes (HD-ZIP I to IV, BEL, KNOX, PLINC, WOX). Other newly identified genes allowed us to characterize PHD, DDT, NDX, and LD genes as members of four new evolutionary classes and to define two additional classes, which we named SAWADEE and PINTOX. Our comprehensive analysis allowed us to identify several newly characterized conserved motifs, including novel zinc finger motifs in SAWADEE and DDT. Members of the BEL and KNOX classes were found in Chlorobionta (green plants) and in Rhodophyta. We found representatives of the DDT, WOX, and PINTOX classes only in green plants, including unicellular green algae, moss, and vascular plants. All 14 homeobox gene classes were represented in flowering plants, Selaginella, and moss, suggesting that they had already differentiated in the last common ancestor of moss and vascular plants

A population-specific material model for sagittal craniosynostosis to predict surgical shape outcomes

Sagittal craniosynostosis consists of premature fusion (ossification) of the sagittal suture during infancy, resulting in head deformity and brain growth restriction. Spring-assisted cranioplasty (SAC) entails skull incisions to free the fused suture and insertion of two springs (metallic distractors) to promote cranial reshaping. Although safe and effective, SAC outcomes remain uncertain. We aimed hereby to obtain and validate a skull material model for SAC outcome prediction. Computed tomography data relative to 18 patients were processed to simulate surgical cuts and spring location. A rescaling model for age matching was created using retrospective data and validated. Design of experiments was used to assess the effect of different material property parameters on the model output. Subsequent material optimization—using retrospective clinical spring measurements—was performed for nine patients. A population-derived material model was obtained and applied to the whole population. Results showed that bone Young’s modulus and relaxation modulus had the largest effect on the model predictions: the use of the population-derived material model had a negligible effect on improving the prediction of on-table opening while significantly improved the prediction of spring kinematics at follow-up. The model was validated using on-table 3D scans for nine patients: the predicted head shape approximated within 2 mm the 3D scan model in 80% of the surface points, in 8 out of 9 patients. The accuracy and reliability of the developed computational model of SAC were increased using population data: this tool is now ready for prospective clinical application

Staff experiences in promoting a sense of coherence for inmates in Sweden

Introduktion: Hälsan hos intagna på anstalter är sämre än hos den generella populationen. Att ha känslan av sammanhang är en viktig faktor för upplevd god hälsa samt för att kunna hantera stressfaktorer som uppkommer i livet. Teorin av känslan av sammanhang kretsar kring tre viktiga konstruktioner: begriplighet, hanterbarhet och meningsfullhet. Personalen på kriminalvårdsanstalterna är de individer som arbetar närmast de intagna under deras vistelse på anstalt och personalen är de som kommunicerar och möter dem mest under deras verkställighet. Syfte: Syftet med studien är att undersöka kriminalvårdspersonalens erfarenheter av att främja begriplighet, hanterbarhet och meningsfullhet för intagna individer på anstalt. Metod: Den här studien använde en kvalitativ ansats där sex tidigare eller nuvarande kriminalvårdsanställda intervjuades. Datamaterialet analyserades med kvalitativ innehållsanalys enligt Graneheim och Lundman (2004). Resultat: Resultatet identifierade fem kategorier relaterat till personalens förmåga att främja känslan av sammanhang för intagna vilka var; sysselsättning, bemötande, verktyg, hinder och positiva resultat. De fem kategorierna var områden där kriminalvårdspersonalen upplevde sig erfara främjandet av begriplighet, hanterbarhet och meningsfullhet för de intagna på anstalt samt vilka hinder men även positiva resultat de upplevde. Slutsats: Sammanfattningsvis visade studien på att det fanns erfarenhet bland kriminalvårdspersonalen av att främja teorins tre komponenter för intagna på anstalt. Framtida forskning föreslås vad gäller att undersöka hur känslan av sammanhang och dess tre komponenter kan användas som en del i det hälsofrämjande arbetet på anstalt.Introduction: Health among inmates in custody is worse compared to the general population. Having a sense of coherence is an important factor for perceived good health as well as to be able to handle stress factors that arise in life. The theory of sense of coherence centers around three important constructs: comprehensibility, manageability and meaningfulness. The staff of correctional facilities are the people who work closest to the inmates during their stay in custody and staff are those who communicate and meet them the most during their enforcement. Aim: The aim of the study is to examine the correctional staff's experiences of promoting comprehensibility, manageability and meaningfulness for incarcerated individuals in custody. Methods: This research used a qualitative approach where six former or current correctional officers were interviewed. The data was analyzed with qualitative content analysis according to Graneheim and Lundman (2004). Results: The results identified five categories related to staff´s ability to promote a sense of coherence for inmates, including were; occupation, interactions, tools, obstacles and positive results. Conclusion: In summary, the study showed that correctional staff had experience in promoting the theory´s three components for inmates in custody. Future research is suggested in terms of investigating how sense of coherence and its three components can be used as part of the health promotion work in custody

Tillämpning av flexibilitet i svenska militära styrdokument

Today's technological and unstable society places greater demands on military organizations to deal with military surprises and uncertainties. One method of dealing with these problems is by incorporating flexibility. Researcher Meir Finkel presents a theoretical framework that advances flexibility as a governing principle that enables military organizations to handle surprises and uncertainties. However, for military organisations there are two main problems with applying new methods on how they should act, firstly to translate it into concepts and operations, secondly to infuse the range of doctrines and regulations to influence the entire organization. Therefore, the purpose of this study is to increase the knowledge of how flexibility is applied in central military governing documents. And, to discuss any correlation between the documents and what effect the implementation may have on the organization’s flexibility. Since the Swedish Armed forces explicitly strive for flexibility, Finkel's theoretical framework aims to illustrate how flexibility has been applied. This was achieved by examining Sweden’s operational and naval doctrine through a qualitative text analysis. The result shows that flexibility plays a significant role in both Sweden's operational and naval doctrine as it has successfully been applied. Nonetheless, both doctrines present elements that may affect flexibility negatively and could therefore, limit the efficiency to deal with military surprises and uncertainties