Fast Locality-Sensitive Hashing Frameworks for Approximate Near Neighbor Search

The Indyk-Motwani Locality-Sensitive Hashing (LSH) framework (STOC 1998) is a general technique for constructing a data structure to answer approximate near neighbor queries by using a distribution $\mathcal{H}$ over locality-sensitive hash functions that partition space. For a collection of $n$ points, after preprocessing, the query time is dominated by $O(n^{\rho} \log n)$ evaluations of hash functions from $\mathcal{H}$ and $O(n^{\rho})$ hash table lookups and distance computations where $\rho \in (0,1)$ is determined by the locality-sensitivity properties of $\mathcal{H}$. It follows from a recent result by Dahlgaard et al. (FOCS 2017) that the number of locality-sensitive hash functions can be reduced to $O(\log^2 n)$, leaving the query time to be dominated by $O(n^{\rho})$ distance computations and $O(n^{\rho} \log n)$ additional word-RAM operations. We state this result as a general framework and provide a simpler analysis showing that the number of lookups and distance computations closely match the Indyk-Motwani framework, making it a viable replacement in practice. Using ideas from another locality-sensitive hashing framework by Andoni and Indyk (SODA 2006) we are able to reduce the number of additional word-RAM operations to $O(n^\rho)$.Comment: 15 pages, 3 figure

Distributed Nested Rollout Policy for Same Game

Nested Rollout Policy Adaptation (NRPA) is a Monte Carlo search heuristic for puzzles and other optimization problems. It achieves state-of-the-art performance on several games including SameGame. In this paper, we design several parallel and distributed NRPA-based search techniques, and we provide a number of experimental insights about their execution. Finally, we use our best implementation to discover 15 better scores for 20 standard SameGame boards

Hands-on time during cardiopulmonary resuscitation is affected by the process of teambuilding: a prospective randomised simulator-based trial

BACKGROUND: Cardiac arrests are handled by teams rather than by individual health-care workers. Recent investigations demonstrate that adherence to CPR guidelines can be less than optimal, that deviations from treatment algorithms are associated with lower survival rates, and that deficits in performance are associated with shortcomings in the process of team-building. The aim of this study was to explore and quantify the effects of ad-hoc team-building on the adherence to the algorithms of CPR among two types of physicians that play an important role as first responders during CPR: general practitioners and hospital physicians. METHODS: To unmask team-building this prospective randomised study compared the performance of preformed teams, i.e. teams that had undergone their process of team-building prior to the onset of a cardiac arrest, with that of teams that had to form ad-hoc during the cardiac arrest. 50 teams consisting of three general practitioners each and 50 teams consisting of three hospital physicians each, were randomised to two different versions of a simulated witnessed cardiac arrest: the arrest occurred either in the presence of only one physician while the remaining two physicians were summoned to help ("ad-hoc"), or it occurred in the presence of all three physicians ("preformed"). All scenarios were videotaped and performance was analysed post-hoc by two independent observers. RESULTS: Compared to preformed teams, ad-hoc forming teams had less hands-on time during the first 180 seconds of the arrest (93 +/- 37 vs. 124 +/- 33 sec, P > 0.0001), delayed their first defibrillation (67 +/- 42 vs. 107 +/- 46 sec, P > 0.0001), and made less leadership statements (15 +/- 5 vs. 21 +/- 6, P > 0.0001). CONCLUSION: Hands-on time and time to defibrillation, two performance markers of CPR with a proven relevance for medical outcome, are negatively affected by shortcomings in the process of ad-hoc team-building and particularly deficits in leadership. Team-building has thus to be regarded as an additional task imposed on teams forming ad-hoc during CPR. All physicians should be aware that early structuring of the own team is a prerequisite for timely and effective execution of CPR

HIVToolbox, an Integrated Web Application for Investigating HIV

Many bioinformatic databases and applications focus on a limited domain of knowledge federating links to information in other databases. This segregated data structure likely limits our ability to investigate and understand complex biological systems. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and allows virologists and structural biologists to access sequence, structure, and functional relationships in an intuitive web application. HIV-1 integrase protein was used as a case study to show the utility of this application. We show how data integration facilitates identification of new questions and hypotheses much more rapid and convenient than current approaches using isolated repositories. Several new hypotheses for integrase were created as an example, and we experimentally confirmed a predicted CK2 phosphorylation site. Weblink: [http://hivtoolbox.bio-toolkit.com

Track A Basic Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138319/1/jia218438.pd

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Effects of high pressure treatment on the rennet coagulation and cheese-making properties of heated milk

In this study, the effect of high pressure (HP) treatment (0-30 min at 100-600 MPa at 20 degrees C, where treatment for 0 min implies the immediate release of pressure after reaching the desired level) on the rennet coagulation and cheese-making properties of milk heated at 90 degrees C for 10 min was investigated. Unpressudsed heated milk or heated milk treated for 0 min at 100 MPa was not coagulable by rennet; however, heated milk treated at 250-600 MPa for 0-30 min had a rennet coagulation time (RCT) equal to, or lower than, that of unheated unpressurised milk; RCT decreased with increasing pressure and treatment time. The strength of he rennet-induced coagulum from heated milk treated at 250-600 MPa for 30 min or 400 or 600 MPa for 0 min was considerably higher than that of unheated unpressurised milk. Furthermore, the yield of cheese curd from HP-treated heated milk was similar to 15% higher than that from unheated unpressurised milk and the protein content of the whey was similar to 30% lower, regardless of pressure or treatment time, whereas the moisture content of the curd was not significantly influenced. These results indicate that by the application of a heat treatment, followed by a HP treatment, milk with superior rennet coagulation and cheese-making properties can be obtained. (c) 2005 Elsevier Ltd. All rights reserved

Effects of high pressure on some constituents and properties of buffalo milk

In this study, effects of high pressure (HP) on some constituents and properties of buffalo milk were examined. HIP treatment at 100-600 MPa for 30 min affected casein micelle size only slightly, whereas treatment at 800 MPa increased it by ∼ 35%. Levels of non-micellar as and β-caseins were increased by treatment > 250 MPa, and were highest after treatment at 400-80OMPa. The level of non-micellar calcium increased with increasing pressure up to 600 MPa. The L*-value of the milk decreased gradually with increasing pressure, from ∼ 82 for untreated milk to ∼ 65 for milk treated at 800 MPa. Milk pH was increased by ∼ 0(.)07 units after treatment at 100-800 MPa, with no significant difference between treatment pressures. Denaturation of α-lactalbumin occurred at pressures ≥ 400 MPa, and reached > 90% after treatment at 800 MPa, whereas β-lactoglobulin (β-Ig) was denatured > 100 MPa, reaching ∼ 100% after treatment at 400 MPa; after treatment ≥ 400MPa, all β-Ig was associated with the casein micelles. The rennet coagulation time of buffalo milk increased with increasing pressure, whereas the strength of the coagulum formed decreased after treatment at 250-800 MPa. Overall, HP treatment affected many constituents and properties of buffalo milk; some of these effects have also been observed in the milk from other species, but the extent of the effects, and the pressure at which they occurred, differed considerably