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Summary: The breadth‐first search procedure is an algorithm that traverses the vertices of a graph, determining the distance from each vertex to the initial vertex. The distance is infinite for a non‐reachable vertex from the starting vertex. Despite having an efficient serial version, this important algorithm is irregular, making its effective parallel implementation a daunting task. This paper shows the results of an OpenMP‐based implementation of the breadth‐first search procedure using the bag data structure. Furthermore, the code relied on the C++ programming language. This paper reimplements an existing proposal coded using the Cilk++ programming language. The experiments relied on 32 strongly connected graphs and 31 disconnected graphs in executions performed on two machines. The first machine contained 28 cores and two threads per core. The second machine comprised 48 processing cores, with hyperthreading disabled. Regarding the serial version, the parallel implementation yielded a speedup of up to 20× when using 28 processing cores and up to 25× when using 56 threads in tests performed on a machine with the first generation of Intel® Xeon® Scalable processors. Furthermore, the new parallel implementation yielded speedups of up to 45× when using 48 cores in experiments performed on a machine with the second generation of Intel® Xeon® Scalable processors. [ABSTRACT FROM AUTHOR]

Seeking to understand the defense mechanisms of tilapia to assist in the health management of fish farms, associated with the lack of information on the use of COX-2 inhibitors in teleost fish, this study aimed to identify important aspects involved in the pathophysiology of the chronic inflammatory reaction in Nile tilapia, Oreochromis niloticus, by evaluating the antiinflammatory activity of celecoxib on the kinetics of migration and formation of gigantocytes in the foreign body response. For this purpose, 72 tilapia were used (Oreochromis niloticus), placed in 9 aquariums (n=8), with a capacity of 100 L of water each, consisting of the following treatments: Control - subjected to inflammatory stimulus without treatment with Celecoxib; TC - Conventional treatment with oral administration of 3mg/kg of Celecoxib after inflammatory stimulus; TP - Prolonged treatment with oral administration of 3mg/kg of Celecoxib for one week before and continuously after the inflammatory stimulus. 8 animals were evaluated per treatment in three periods, that is: 2, 4 and 8 days post-implantation (DPI) of the coverslips, with blood samples being collected to perform the differential leukocyte count in blood extensions, as well as collecting the coverslips. for cytological study. In the later phase of the inflammatory process (8DPI), a decrease in the cellular accumulation of macrophages and formation of polykaryotes was observed on the coverslips of tilapia treated with celecoxib, demonstrating the anti-inflammatory effect of this COX-2 inhibitor, associated with a significant decrease in the number of circulating monocytes in animals receiving conventional treatment. Tilapia treated with celecoxib (TC and TP) showed a significant decrease in total leukocyte count in the initial phase of the inflammatory process (2DPI), characterized by neutropenia and lymphopenia. Therefore, both treatment protocols (TC and TP) with 3mg/kg of celecoxib modulated the foreign body-type inflammatory response of tilapia by acting on the kinetics of macrophage accumulation and formation of polykaryotes on glass coverslips implanted in the subcutaneous tissue, demonstrating a correlation to the dynamics of circulating leukocytes. These results help to understand the role of prostanoids during the chronic inflammatory reaction of tilapia. [ABSTRACT FROM AUTHOR]

In this paper we present moving meshes for the numeric resolution of partial differential equations. We describe some important concepts on this topic and point to existing body of work for the solution of partial differential equations using the methods of finite volumes and finite elements, both with moving meshes.

In this paper, an overview on subjects and its matching reference books for the teaching of two algorithm classes in undergraduate courses on Computer Science, Computer Engineering, Information Systems, Computer Science Teaching, Software Engineering and other similar ones is given. Complementary literature for these subjects are also recommended.

In this work, we report a systematic investigation of upconversion losses and their effects on fluorescence quantum efficiency and fractional thermal loading in Nd3+-doped fluoride glasses. The energy transfer upconversion (γup) parameter, which describes upconversion losses, was experimentally determined using different methods: thermal lens (TL) technique and steady state luminescence (SSL) measurements. Additionally, the upconversion parameter was also obtained from energy transfer models and excited state absorption measurements. The results reveal that the microscopic treatment provided by the energy transfer models is similar to the macroscopic ones achieved from the TL and SSL measurements because similar γup parameters were obtained. Besides, the achieved results also point out the migration-assisted energy transfer according to diffusion-limited regime rather than hopping regime as responsible for the upconversion losses in Nd-doped glasses. [ABSTRACT FROM AUTHOR]

In this work we present a study of energy transfer processes in Yb3+-doped phosphate glasses with different OH- contents and Yb3+ concentrations. Fluorescence and thermal lens (TL) techniques were used in order to analyze the Yb3+–OH- and Yb3+-other impurity interactions. The role of OH- groups is also presented and discussed. The results show that in the low concentration region up to ∼3×1020 Yb ions/cm3, the interaction between Yb3+ and OH radicals is the dominant process reducing the lifetime, increasing the TL dioptric power, and then endangering the performance of the system. For the high Yb3+ concentration limit, the Yb3+-other impurity interaction, which is favored by energy migration, is comparable to the Yb3+–OH- energy transfer, even for high OH- concentration. The nonradiative decay rate due to hydroxyl groups follows Förster-Dexter theory [Ann. Phys. 2, 55 (1948); J. Chem. Phys. 21, 836 (1953)] except at low Yb3+ concentration, being more active at low OH- levels, where quenching rate is probably due to several impurities. [ABSTRACT FROM AUTHOR]

This work employs the Z-scan technique with 120 fs pulses to investigate the singlet excited state absorption spectra of tetrapyridyl and tetrasulfonatophenyl porphyrins. We have used a three-energy-level model to adjust Z-scan curves in order to obtain the singlet excited absorption cross section from 460 to 800 nm. Starting from these values, we determine the spectra of the ratio between excited and ground singlet state absorption cross sections, whose values are as good as the best found in the literature for reverse saturable absorbers. The results obtained point these porphyrins as good candidates for applications in optical limiting of ultrashort pulses. [ABSTRACT FROM AUTHOR]