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

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

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. Journal of Supercomputing. 59(3):1533-1551. https://doi.org/10.1007/s11227-011-0566-8S15331551593IBM journal of Research and Development staff (2008) Overview of the IBM blue gene/P project. IBM J Res Dev 52(1/2):199–220Blocksome M, Archer C, Inglett T, McCarthy P, Mundy M, Ratterman J, Sidelnik A, Smith B, Almási G, Castaños J, Lieber D, Moreira J, Krishnamoorthy S, Tipparaju V, Nieplocha J (2006) Design and implementation of a one-sided communication interface for the IBM eServer Blue Gene® supercomputer. In: Proceedings of the 2006 ACM/IEEE conference on supercomputing, SC ’06, Tampa, FL, USA, November 2006, pp 54–54Kumar S, Dózsa G, Almasi G, Heidelberger P, Chen D, Giampapa M, Blocksome M, Faraj A, Parker J, Ratterman J, Smith BE, Archer C (2008) The deep computing messaging framework: generalized scalable message passing on the blue gene/P supercomputer. 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