bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperbolic orbifold tutte embeddings
Authors: Aigerman Noam , Lipman Yaron 
Published: November 2016

Tutte's embedding is one of the most popular approaches for computing parameterizations of surface meshes in computer graphics and geometry processing. Its popularity can be attributed to its simplicity, the guaranteed bijectivity of the embedding, and its relation to continuous harmonic mappings.
In this work we extend Tutte's embedding into hyperbolic cone-surfaces called orbifolds. Hyperbolic orbifolds are simple surfaces exhibiting different topologies and cone singularities and therefore provide a flexible and useful family of target domains. The hyperbolic Orbifold Tutte embedding is defined as a critical point of a Dirichlet energy with special boundary constraints and is proved to be bijective, while also satisfying a set of points-constraints. An efficient algorithm for computing these embeddings is developed.
We demonstrate a powerful application of the hyperbolic Tutte embedding for computing a consistent set of bijective, seamless maps between all pairs in a collection of shapes, interpolating a set of user-prescribed landmarks, in a fast and robust manner.
Be my guest
Authors: Wang Tianzheng , Chabbi Milind , Kimura Hideaki 
Published: November 2016

The MCS lock is one of the most prevalent queuing locks. It provides fair scheduling and high performance on massively parallel systems. However, the MCS lock mandates a
bring-your-own-context
policy: each lock user must provide an additional context (i.e., a queue node) to interact with the lock. This paper proposes MCSg, a variant of the MCS lock that relaxes this restriction.

Our key observation is that
not all lock users are created equal
. We analyzed how locks are used in massively-parallel modern systems, such as NUMA-aware operating systems and databases. We found that such systems often have a small number of "regular" code paths that enter the lock very frequently. Such code paths are the primary beneficiary of the high scalability of MCS locks.

However, there are also many "guest" code paths that infrequently enter the lock and do not need the same degree of fairness to access the lock (e.g., background tasks that only run periodically with lower priority). These guest users, which are typically spread out in various modules of the software, prefer context-free locks, such as ticket locks.
MCSg provides these guests a context-free interface while regular users still enjoy the benefits provided by MCS. It can also be used as a drop-in replacement of MCS for more advanced locks, such as cohort locking. We also propose MCSg++, an extended version of MCSg, which avoids guest starvation and non-FIFO behaviors that might happen with MCSg.
Our evaluation using microbenchmarks and the TPC-C database benchmark on a 16-socket, 240-core server shows that both MCSg and MCSg++ preserve the benefits of MCS for regular users while providing a context-free interface for guests.
Multi-core on-the-fly SCC decomposition
Authors: Bloemen Vincent , Laarman Alfons , van de Pol Jaco 
Published: November 2016

The main advantages of Tarjan's strongly connected component (SCC) algorithm are its linear time complexity and ability to return SCCs on-the-fly, while traversing or even generating the graph. Until now, most
parallel
SCC algorithms sacrifice both: they run in quadratic worst-case time and/or require the full graph in advance.

The current paper presents a novel parallel, on-the-fly SCC algorithm. It preserves the linear-time property by letting workers explore the graph randomly while carefully communicating partially completed SCCs. We prove that this strategy is correct. For efficiently communicating partial SCCs, we develop a concurrent, iterable disjoint set structure (combining the union-find data structure with a cyclic list).
We demonstrate scalability on a 64-core machine using 75 real-world graphs (from model checking and explicit data graphs), synthetic graphs (combinations of trees, cycles and linear graphs), and random graphs. Previous work did not show speedups for graphs containing a large SCC. We observe that our parallel algorithm is typically 10-30× faster compared to Tarjan's algorithm for graphs containing a large SCC. Comparable performance (with respect to the current state-of-the-art) is obtained for graphs containing many small SCCs.
Scalable adaptive NUMA-aware lock
Authors: Zhang Mingzhe , Lau Francis C. M. , Wang Cho-Li , Cheng Luwei , Chen Haibo 
Published: November 2016

Scalable locking is a key building block for scalable multi-threaded software. Its performance is especially critical in multi-socket, multi-core machines with non-uniform memory access (NUMA). Previous schemes such as local locking and remote locking only perform well under a certain level of contention, and often require non-trivial tuning for a particular configuration. Besides, for large NUMA systems, because of unmanaged lock server's nomination, current distance-first NUMA policies cannot perform satisfactorily.
In this work, we propose SANL, a locking scheme that can deliver high performance under various contention levels by adaptively switching between the local and the remote lock scheme. Furthermore, we introduce a new NUMA policy for the remote lock that jointly considers node distances and server utilization when choosing lock servers. A comparison with seven representative locking schemes shows that SANL outperforms the others in most contention situations. In one group test, SANL is 3.7 times faster than RCL lock and 17 times faster than POSIX mutex.
SPIRIT
Authors: Hegde Nikhil , Liu Jianqiao , Kulkarni Milind 
Published: November 2016

Repeated, depth-first traversal of trees is a common algorithmic pattern in an important set of applications from diverse domains such as cosmological simulations, data mining, and computer graphics. As these applications operate over massive data sets, it is often necessary to distribute the trees to process all of the data.
In this work, we introduce SPIRIT, a runtime system to ease the writing of distributed tree applications. SPIRIT automates the challenging tasks of tree distribution, optimizing communication and parallelizing independent computations. The common algorithmic pattern in tree traversals is exploited to effectively schedule parallel computations and improve locality. As a result, pipeline parallelism in distributed traversals is identified, which is complemented by load-balancing, and locality-enhancing, message aggregation optimizations. Evaluation of SPIRIT on tree traversal in Point Correlation (PC) shows a scalable system, achieving speedups upto 38x on a 16-node, 64 process system compared to a 1-node, baseline configuration. We also find that SPIRIT results in substantially less communication and achieves significant performance improvements over implementations in other distributed graph systems.
Concurrent hash tables
Authors: Maier Tobias , Sanders Peter , Dementiev Roman 
Published: November 2016

Concurrent hash tables are one of the most important concurrent data structures with numerous applications. Since hash table accesses can dominate the execution time of the overall application, we need implementations that achieve good speedup. Unfortunately, currently available concurrent hashing libraries turn out to be far away from this requirement in particular when contention on some elements occurs.
Our starting point for better performing data structures is a fast and simple lock-free concurrent hash table based on linear probing that is limited to word-sized key-value types and does not support dynamic size adaptation. We explain how to lift these limitations in a provably scalable way and demonstrate that dynamic growing has a performance overhead comparable to the same generalization in sequential hash tables.
We perform extensive experiments comparing the performance of our implementations with six of the most widely used concurrent hash tables. Ours are considerably faster than the best algorithms with similar restrictions and an order of magnitude faster than the best more general tables. In some extreme cases, the difference even approaches four orders of magnitude.
Acute limb heating improves macro- and microvascular dilator function in the leg of aged humans
Authors: Romero Steven A. , Gagnon Daniel , Adams Amy N. , Cramer Matthew N. , Kouda Ken , Crandall Craig G. 
Published: November 2016

Local heating of an extremity increases blood flow and vascular shear stress throughout the arterial tree. Local heating acutely improves macrovascular dilator function in the upper limbs of young healthy adults through a shear stress-dependent mechanism but has no such effect in the lower limbs of this age group. The effect of acute limb heating on dilator function within the atherosclerotic prone vasculature of the lower limbs of aged adults is unknown. Therefore, the purpose of this study was to test the hypothesis that acute lower limb heating improves macro- and microvascular dilator function within the leg vasculature of aged adults. Nine young and nine aged adults immersed their lower limbs at a depth of ~33 cm into a heated (~42°C) circulated water bath for 45 min. Before and 30 min after heating, macro (flow-mediated dilation)- and microvascular (reactive hyperemia) dilator functions were assessed in the lower limb, following 5 min of arterial occlusion, via Doppler ultrasound. Compared with preheat, macrovascular dilator function was unchanged following heating in young adults ( P = 0.6) but was improved in aged adults ( P = 0.04). Similarly, microvascular dilator function, as assessed by peak reactive hyperemia, was unchanged following heating in young adults ( P = 0.1) but was improved in aged adults ( P < 0.01). Taken together, these data suggest that acute lower limb heating improves both macro- and microvascular dilator function in an age dependent manner. NEW & NOTEWORTHY We demonstrate that lower limb heating acutely improves macro- and microvascular dilator function within the atherosclerotic prone vasculature of the leg in aged adults. These findings provide evidence for a potential therapeutic use of chronic lower limb heating to improve vascular health in primary aging and various disease conditions.
Positive versus negative effects of VEGF165 on Ca2+ signaling and NO production in human endothelial cells
Authors: Boeldt Derek S. , Krupp Jennifer , Yi Fu-Xian , Khurshid Nauman , Shah Dinesh M. , Bird Ian M. 
Published: November 2016

The role increased vascular endothelial growth factor (VEGF) plays in vascular function during normal vs. preeclamptic pregnancy has been a source of some controversy of late. In this study, we seek to understand how VEGF165 influences vasodilator production via Ca2+ signaling mechanisms in human endothelial cells. We utilize human umbilical vein endothelial cells (HUVEC) as well as intact ex vivo human umbilical vein (HUV Endo) to address direct stimulation of Ca2+ and NO by VEGF165 alone, as well as the effect of VEGF165 on subsequent ATP-stimulated Ca2+ signaling and NO production. We show that VEGF165 stimulates Ca2+ responses in both HUVEC and HUV Endo, which results in a corresponding increase in NO production in HUV Endo. Longer-term VEGF165 pretreatment then inhibits sustained Ca2+ burst responses to ATP in HUVEC and HUV Endo. This is paralleled by a corresponding drop in ATP-stimulated NO production in HUV Endo, likely through inhibition of Cx43 gap-junction function. Thus, although VEGF165 makes a small initial positive impact on vasodilator production via direct stimulation of Ca2+ responses, this is outweighed by the greater subsequent negative impact on Ca2+ bursts and vasodilator production promoted by more potent agonists such as ATP. Overall, elevated levels of VEGF165 associated with preeclampsia could contribute to the endothelial dysfunction by preventing Ca2+ bursts to other agonists including but not limited to ATP. NEW & NOTEWORTHY In this manuscript, we show that VEGF levels associated with preeclampsia are a net negative contributor to potential vasodilator production in both a human ex vivo and in vitro endothelial cell model. Therefore, pharmacological targeting of VEGF-stimulated signaling pathways could be a novel treatment modality for preeclampsia-related hypertension.
Aurora A and NF-κB Survival Pathway Drive Chemoresistance in Acute Myeloid Leukemia via the TRAF-Interacting Protein TIFA
Authors: Wei Tong-You Wade , Wu Pei-Yu , Wu Ting-Jung , Hou Hsin-An , Chou Wen-Chien , Teng Chieh-Lin Jerry , Lin Chih-Ru , Chen Jo-Mei Maureen , Lin Ting-Yang , Su Hsiang-Chun , Huang Chia-Chi Flora , Yu Chang-Tze Ricky , Hsu Shih-Lan , Tien Hwei-Fang , Tsai Ming-Daw 
Published: November 2016

AbstractAurora A–dependent NF-κB signaling portends poor prognosis in acute myeloid leukemia (AML) and other cancers, but the functional basis underlying this association is unclear. Here, we report that Aurora A is essential for Thr9 phosphorylation of the TRAF-interacting protein TIFA, triggering activation of the NF-κB survival pathway in AML. TIFA protein was overexpressed concurrently with Aurora A and NF-κB signaling factors in patients with de novo AML relative to healthy individuals and also correlated with poor prognosis. Silencing TIFA in AML lines and primary patient cells decreased leukemic cell growth and chemoresistance via downregulation of prosurvival factors Bcl-2 and Bcl-XL that support NF-κB–dependent antiapoptotic events. Inhibiting TIFA perturbed leukemic cytokine secretion and reduced the IC50 of chemotherapeutic drug treatments in AML cells. Furthermore, in vivo delivery of TIFA-inhibitory fragments potentiated the clearance of myeloblasts in the bone marrow of xenograft-recipient mice via enhanced chemotoxicity. Collectively, our results showed that TIFA supports AML progression and that its targeting can enhance the efficacy of AML treatments. Cancer Res; 77(2); 494–508. ©2016 AACR.
Combining Molecularly Targeted Agents: Is More Always Better?
Authors: Sundar Raghav , Valeri Nicola , Harrington Kevin J. , Yap Timothy A. 
Published: November 2016

Abstract
The concurrent targeting of critical nodes along key signaling pathways with molecularly targeted agents is a rational antitumor strategy, which has had varying degrees of success. Combinatorial challenges include overcoming synergistic toxicities and establishing whether combinations are truly active, to make “go, no-go” decisions to proceed to later phase trials. Clin Cancer Res; 23(5); 1123–5. ©2016 AACR.
See related article by Calvo et al., p. 1177
Impact of fluctuating thermal regimes on Drosophila melanogaster survival to cold stress
Authors: Javal Marion , Renault David , Colinet Hervé 
Published: November 2016

Temperature directly affects survival, development and reproduction in insects and thereby it is a key environmental driver for geographic distribution and population dynamics. This study aims at testing the survival ofDrosophila melanogasterunder constant low temperatures (CLTs) (2, 3, 4, and 5°C)vs.fluctuating thermal regimes (FTRs). In the latter, the cold stress period was interrupted daily by 2 h pulses at 20°C. Since acclimation enhances cold tolerance, we tested whether benefits of acclimation can combine with those of FTRs. SinceD. melanogasteroverwinters as non-reproductive adults, we tested if actively reproducing adults are more susceptible to cold stress than virgin females that have a much reduced reproductive activity. The results show that short interruptions of cold stress enhanced survival of adult flies. Survival was time- and temperature-dependent. Prior acclimation to low temperature allowed flies to better cope with cold stress under CLTs. On the other hand, acclimated flies did not profit from the benefits of FTRs and even showed lower survival under FTRs, probably because flies deacclimated during the periodic warm intervals. Gravid females were overall less cold tolerant than virgin females, and both survived better under FTRs. Cold survival at pupal stage was much lower than at adult stage, and no clear benefit of FTR was observed in this life stage. Our study highlights critical variables to take into account when designing experiments of prolonged exposure to low temperature in insects.
Eight new species of Andrena Fabricius (Hymenoptera: Apoidea: Andrenidae) from Israel—a Mediterranean hotspot for wild bees
Authors: PISANTY GIDEON , SCHEUCHL ERWIN , DORCHIN NETTA 
Published: November 2016

More than 150 solitary bee species of the genus Andrena Fabricius are known from Israel and the West Bank, where they are distributed along a broad climatic gradient and diverse habitats and vegetation types. Extensive collecting throughout Israel in recent years has yielded eight new species and one new subspecies, adding to the rich bee fauna of the region: A. crocusella Pisanty & Scheuchl n. sp., A. danini Pisanty & Scheuchl n. sp., A. hermonella Scheuchl & Pisanty n. sp., A. israelica Scheuchl & Pisanty n. sp., A. judaea Scheuchl & Pisanty n. sp., A. menahemella Scheuchl & Pisanty n. sp., A. palaestina Pisanty & Scheuchl n. sp., A. perahia Pisanty & Scheuchl n. sp., and A. sphecodimorpha mediterranea Pisanty & Scheuchl n. ssp. The previously unknown female of A. fimbriatoides Scheuchl 2004 and male of A. wolfi Gusenleitner & Scheuchl 2000 are also described here for the first time. The discovery of males of A. wolfi lead us to reinstate A. iohannescaroli Nobile 2000 as a valid taxon. Detailed morphological description and differential diagnosis against closest relatives are provided for all species, as well as information on the distribution, phenology and flower visitation, when available. A neotype is designated for A. sphecodimorpha Hedicke, the holotype of which is considered to be lost. Additional collecting efforts in diverse habitats and seasons, incorporating diverse collecting techniques, are required in order to deepen our knowledge of the rich bee fauna in threatened habitats in the Mediterranean Basin, which constitutes one of the world’s major hotspots for wild bees.
The Influence of Successive Thermals on Entrainment and Dilution in a Simulated Cumulus Congestus
Authors: Moser Daniel H. , Lasher-Trapp Sonia 
Published: November 2016

Abstract
Cumulus clouds are frequently observed as comprising multiple successive thermals, yet numerical simulations of entrainment have not investigated this level of detail. Here, an idealized simulated cumulus congestus consisting of three successive thermals is used to analyze and understand their role in maintaining the high liquid water content in the core of the cloud, which past 1D modeling studies have suggested can ultimately determine its ability to precipitate. Entrainment and detrainment are calculated directly at the edge of the cloud core at frequent time intervals. Entrainment maxima occur at the rear of the toroidal circulation associated with each thermal and thus are transient features in the lifetime of multithermal clouds. The evolution of the least diluted parcels within each thermal shows that the entrainment rates alone cannot predict the erosion of the high liquid water content cores. A novel analysis of samples of entrained and detrained air within each successive thermal illustrates tendencies for even positively buoyant air, containing condensate, to be entrained by later thermals that rise in the wakes of their predecessors, limiting their dilution. The later thermals can achieve greater depths and produce precipitation when a single thermal could not. Future work is yet needed to evaluate the generality of these results using multiple clouds simulated in different environments with less-idealized modeling frameworks. Implications for current cumulus parameterizations are briefly discussed.
Impact of Tropical SSTs in the North Atlantic and Southeastern Pacific on the Eastern Pacific ITCZ
Authors: Song Fengfei , Zhang Guang J. 
Published: November 2016

Abstract
During boreal spring, observations show a double ITCZ over the eastern Pacific, with the northern ITCZ stronger than the southern ITCZ. However, it is opposite in most climate models. It is also evident that there exists a cold bias in tropical North Atlantic (TNA) sea surface temperature (SST) and a warm bias in southeastern Pacific (SEP) SST. In this study, the influences of TNA and SEP SSTs on the double-ITCZ bias are investigated by prescribing the observed SST in these regions in the NCAR CESM1. Results show that when TNA SST is prescribed, the northern ITCZ is substantially enhanced and the southern ITCZ is moderately reduced, although the SST response in these regions is small. When the SEP SST is prescribed, the southern ITCZ is reduced considerably. When both TNA and SEP SSTs are prescribed, the double-ITCZ bias is reduced by ~68%. Moisture budget analysis suggests that dynamics, mainly the low-level convergence change, determines the above precipitation changes. Based on a mixed layer model, changes in low-level convergence are shown to be determined by surface pressure Ps changes. With prescribed TNA/SEP SSTs, SST gradients change the Ps in the region directly via the Lindzen–Nigam mechanism. The corresponding low-level circulation changes affect the 850-hPa thermodynamic state in a wider region, which in turn not only strengthens the SST-induced Ps change locally but also leads to Ps changes remotely, including the northern ITCZ region. Furthermore, the low-level convergence changes the vertical structure of moist static energy, altering the atmospheric stability and modulating precipitation distribution.
Detectable Anthropogenic Shift toward Heavy Precipitation over Eastern China
Authors: Ma Shuangmei , Zhou Tianjun , Stone Dáithí A. , Polson Debbie , Dai Aiguo , Stott Peter A. , von Storch Hans , Qian Yun , Burke Claire , Wu Peili , Zou Liwei , Ciavarella Andrew 
Published: November 2016

Abstract
Changes in precipitation characteristics directly affect society through their impacts on drought and floods, hydro-dams, and urban drainage systems. Global warming increases the water holding capacity of the atmosphere and thus the risk of heavy precipitation. Here, daily precipitation records from over 700 Chinese stations from 1956 to 2005 are analyzed. The results show a significant shift from light to heavy precipitation over eastern China. An optimal fingerprinting analysis of simulations from 11 climate models driven by different combinations of historical anthropogenic (greenhouse gases, aerosols, land use, and ozone) and natural (volcanic and solar) forcings indicates that anthropogenic forcing on climate, including increases in greenhouse gases (GHGs), has had a detectable contribution to the observed shift toward heavy precipitation. Some evidence is found that anthropogenic aerosols (AAs) partially offset the effect of the GHG forcing, resulting in a weaker shift toward heavy precipitation in simulations that include the AA forcing than in simulations with only the GHG forcing. In addition to the thermodynamic mechanism, strengthened water vapor transport from the adjacent oceans and by midlatitude westerlies, resulting mainly from GHG-induced warming, also favors heavy precipitation over eastern China. Further GHG-induced warming is predicted to lead to an increasing shift toward heavy precipitation, leading to increased urban flooding and posing a significant challenge for mega-cities in China in the coming decades. Future reductions in AA emissions resulting from air pollution controls could exacerbate this tendency toward heavier precipitation.