167 research outputs found
Eliciting Intelligence With the Scharff Technique:Interviewing More and Less Cooperative and Capable Sources
The objective was to compare the efficacy of the Scharff technique (conceptualized as 5 tactics) with the direct approach (open and direct questions) as a means of eliciting intelligence from human sources. The interview techniques were used with 4 different types of sources varying in their levels of both cooperation and capability to provide information as follows: (a) less willing/less able, (b) less willing/ more able, (c) more willing/less able, and (d) more willing/more able. The sources (N ﰁ 200) were given information about a notional planned terrorist attack and instructed to strike a balance between not revealing too much or too little information in a subsequent interview. Overall, the Scharff technique resulted in significantly more new information than the direct approach, particularly for the less cooperative sources. Furthermore, sources interviewed with the Scharff technique had a more difficult time reading the interviewer’s information objectives and consistently underestimated how much new information they revealed. The study substantiates the Scharff technique as an effective human- intelligence gathering tool
Olfactory function and viral recovery in COVID-19
Olfactory and taste disorders were reported in up to 30%-80% of COVID-19 patients. The purpose of our study was to objectively assess smell impairment in COVID-19 patients and to correlate olfactory function with viral recovery
Scapular body fractures—should we be fixing more of these?
The question of whether we should be fixing more scapular body fractures originates from the historical preference for nonoperative management of these fractures. Recently, there has been a renewed interest in operative management due to the recognition that scapular malunion can cause significant disability. While the treatment pendulum has shifted away from benign neglect, finding the right balance of surgical aggression remains controversial. In general, the majority of scapula fractures can successfully be treated nonoperatively with excellent functional results. However, numerous case studies exist demonstrating poor outcomes of scapular body or neck fractures with increased deformity. The literature suggests that a glenopolar angle (GPA) less than 20 degrees can lead to a significant decrease in shoulder function. Additionally, retrospective studies using lateral border offset (LBO) greater than >2 cm and angulation >45 degrees as a surgical indication demonstrate functional outcomes with near normal strength and range of motion and low complication rates. While numerous cut-offs for surgical indications have been recommended, all indications are considered relative and treatment should be individualized based on patient characteristics and goals
X-ray absorption spectroscopy study of diluted magnetic semiconductors: Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y = Se, Te)
We have investigated 3d electronic states of doped transition metals in II-VI
diluted magnetic semiconductors, Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y =
Se, Te), using the transition-metal L2,3-edge X-ray absorption spectroscopy
(XAS) measurements. In order to explain the XAS spectra, we employed a
tetragonal cluster model calculation, which includes not only the full ionic
multiplet structure but also configuration interaction (CI). The results show
that CI is essential to describe the experimental spectra adequately,
indicating the strong hybridization between the transition metal 3d and the
ligand p orbitals. In the study of Zn1-xMnxY (Y = Se, Te), we also found
considerable spectral change in the Mn L2,3-edge XAS spectra for different
ligands, confirming the importance of the hybridization effects in these
materials.Comment: This paper consists of 22 pages including 4 figures. This paper is
submitted to Physical Review
Isoperimetry and stability of hyperplanes for product probability measures
International audienceWe investigate stationarity and stability of half-spaces as isoperimetric sets for product probability measures, considering the cases of coordinate and non-coordinate half-spaces. Moreover, we present several examples to which our results can be applied, with a particular emphasis on the logistic measure
A cost-effective heuristic to schedule local and remote memory in cluster computers
Cluster computers represent a cost-effective alternative solution to supercomputers. In these systems, it is common to constrain the memory address space of a given processor to the local motherboard. Constraining the system in this way is much cheaper than using a full-fledged shared memory implementation among motherboards. However, memory usage among motherboards can be unfairly balanced. On the other hand, remote memory access (RMA) hardware provides fast interconnects among the motherboards of a cluster. RMA devices can be used to access remote RAM memory from a local motherboard. This work focuses on this capability in order to achieve a better global use of the total RAM memory in the system. More precisely, the address space of local applications is extended to remote motherboards and is used to access remote RAM memory. This paper presents an ideal memory scheduling algorithm and proposes a cost-effective heuristic to allocate local and remote memory among local applications. Compared to the devised ideal algorithm, the heuristic obtains the same (or closely resembling) results while largely reducing the computational cost. In addition, we analyze the impact on the performance of stand alone applications varying the memory distribution among regions (local, local to board, and remote). Then, this study is extended to any number of concurrent applications. Experimental results show that a QoS parameter is needed in order to avoid unacceptable performance degradation. © 2011 Springer Science+Business Media, LLC.This work was supported by Spanish CICYT under Grant TIN2009-14475-C04-01 and by Consolider-Ingenio under Grant CSD2006-00046.Serrano Gómez, M.; Sahuquillo Borrás, J.; Petit Martí, SV.; Hassan Mohamed, H.; Duato Marín, JF. (2012). A cost-effective heuristic to schedule local and remote memory in cluster computers. 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In: Proceedings of the 22nd annual international conference on supercomputing, Island of Kos, Greece, June 2008, pp 94–103Tipparaju V, Kot A, Nieplocha J, Bruggencate MT, Chrisochoides N (2007) Evaluation of remote memory access communication on the cray XT3. In: Proceedings of the 21th international parallel and distributed processing symposium, Long Beach, California, USA, March 2007, pp 1–7Nussle M, Scherer M, Bruning U (2009) A resource optimized remote-memory-access architecture for low-latency communication. In: International conference on parallel processing, Sept 2009, pp 220–227http://www.hypertransport.org/Serrano M, Sahuquillo J, Hassan H, Petit S, Duato J (2010) A scheduling heuristic to handle local and remote memory in cluster computers. In: Proceedings of the 12th IEEE international conference on high performance computing, Melbourne, Australia, Sept 2010, pp 35–42Keltcher CN, McGrath KJ, Ahmed A, Conway P (2003) The AMD opteron processor for multiprocessor servers. 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A new degree of freedom for memory allocation in clusters
Improvements in parallel computing hardware usually involve increments in the number of available resources for a given application such as the number of computing cores and the amount of memory. In the case of shared-memory computers, the increase in computing resources and available memory is usually constrained by the coherency protocol, whose overhead rises with system size, limiting the scalability of the final system. In this paper we propose an efficient and cost-effective way to increase the memory available for a given application by leveraging free memory in other computers in the cluster. Our proposal is based on the observation that many applications benefit from having more memory resources but do not require more computing cores, thus reducing the requirements for cache coherency and allowing a simpler implementation and better scalability. Simulation results show that, when additional mechanisms intended to hide remote memory latency are used, execution time of applications that use our proposal is similar to the time required to execute them in a computer populated with enough local memory, thus validating the feasibility of our proposal. We are currently building a prototype that implements our ideas. The first results from real executions in this prototype demonstrate not only that our proposal works but also that it can efficiently execute applications that make use of remote memory resources. © 2011 Springer Science+Business Media, LLC.This work has been supported by PROMETEO from Generalitat Valenciana (GVA) under Grant PROMETEO/2008/060.Montaner Mas, H.; Silla Jiménez, F.; Fröning, H.; Duato Marín, JF. (2012). A new degree of freedom for memory allocation in clusters. 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Voice-based assessments of trustworthiness, competence, and warmth in blind and sighted adults
The study of voice perception in congenitally blind individuals allows researchers rare insight into how a lifetime of visual deprivation affects the development of voice perception. Previous studies have suggested that blind adults outperform their sighted counterparts in low-level auditory tasks testing spatial localization and pitch discrimination, as well as in verbal speech processing; however, blind persons generally show no advantage in nonverbal voice recognition or discrimination tasks. The present study is the first to examine whether visual experience influences the development of social stereotypes that are formed on the basis of nonverbal vocal characteristics (i.e., voice pitch). Groups of 27 congenitally or early-blind adults and 23 sighted controls assessed the trustworthiness, competence, and warmth of men and women speaking a series of vowels, whose voice pitches had been experimentally raised or lowered. Blind and sighted listeners judged both men’s and women’s voices with lowered pitch as being more competent and trustworthy than voices with raised pitch. In contrast, raised-pitch voices were judged as being warmer than were lowered-pitch voices, but only for women’s voices. Crucially, blind and sighted persons did not differ in their voice-based assessments of competence or warmth, or in their certainty of these assessments, whereas the association between low pitch and trustworthiness in women’s voices was weaker among blind than sighted participants. This latter result suggests that blind persons may rely less heavily on nonverbal cues to trustworthiness compared to sighted persons. Ultimately, our findings suggest that robust perceptual associations that systematically link voice pitch to the social and personal dimensions of a speaker can develop without visual input
Role of nickel in high rate methanol degradation in anaerobic granular sludge bioreactors
The effect of nickel deprivation from the influent of a mesophilic (30°C) methanol fed upflow anaerobic sludge bed (UASB) reactor was investigated by coupling the reactor performance to the evolution of the Methanosarcina population of the bioreactor sludge. The reactor was operated at pH 7.0 and an organic loading rate (OLR) of 5–15 g COD l−1 day−1 for 191 days. A clear limitation of the specific methanogenic activity (SMA) on methanol due to the absence of nickel was observed after 129 days of bioreactor operation: the SMA of the sludge in medium with the complete trace metal solution except nickel amounted to 1.164 (±0.167) g CH4-COD g VSS−1 day−1 compared to 2.027 (±0.111) g CH4-COD g VSS−1 day−1 in a medium with the complete (including nickel) trace metal solution. The methanol removal efficiency during these 129 days was 99%, no volatile fatty acid (VFA) accumulation was observed and the size of the Methanosarcina population increased compared to the seed sludge. Continuation of the UASB reactor operation with the nickel limited sludge lead to incomplete methanol removal, and thus methanol accumulation in the reactor effluent from day 142 onwards. This methanol accumulation subsequently induced an increase of the acetogenic activity in the UASB reactor on day 160. On day 165, 77% of the methanol fed to the system was converted to acetate and the Methanosarcina population size had substantially decreased. Inclusion of 0.5 μM Ni (dosed as NiCl2) to the influent from day 165 onwards lead to the recovery of the methanol removal efficiency to 99% without VFA accumulation within 2 days of bioreactor operation
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