Comparing Individual Versus Team Decision-Making Using Simulated Exercises in a Master of Public Health Program

In line with the complex modern health care system and the increasing importance of interprofessional teams, a powerful strategy to facilitate the acquisition of essential teamwork skills and expose students to complex decision-making processes is learning in teams. The purpose of our study was to obtain empirical evidence of superior decision-making by teams versus individuals in two simulated decision-making exercises conducted 4 months apart. We collected quantitative data from three cohorts of Master of Public Health students to determine if teams make better decisions than individuals (“team effect”) between September and January. Students completed simulated emergency survival exercises requiring them to make correct decisions individually and then as teams. Decision quality was determined by comparison to survival experts’ decisions. We calculated the “team effect” as the gain or loss of mean individual versus group scores across 10 learning teams per cohort for fall and winter exercises. All three cohorts had a consistently small average team effect in September and a much larger team effect in January. Our study showed consistent improvements in decision-making after students had worked in teams for 4 months. Overall, this study demonstrates the potential benefit of incorporating team learning into a public health curriculum and the importance of strategies to teach teamwork in health education. Using simulation in health education and promoting team learning activities can help prepare students for interprofessional collaboration, a part of the demanding public health landscape. These results might help convince students of the benefits of teamwork, facilitate collaborative decision-making, and enhance the learning experience

Rainbow polygons for colored point sets in the plane

Given a colored point set in the plane, a perfect rainbow polygon is a simple polygon that contains exactly one point of each color, either in its interior or on its boundary. Let rb-index(S) denote the smallest size of a perfect rainbow polygon for a colored point set S, and let rb-index(k) be the maximum of rb-index(S) over all k-colored point sets in general position; that is, every k-colored point set S has a perfect rainbow polygon with at most rb-index(k) vertices. In this paper, we determine the values of rb-index(k) up to k=7, which is the first case where rb-index(k)¿k, and we prove that for k=5, [Formula presented] Furthermore, for a k-colored set of n points in the plane in general position, a perfect rainbow polygon with at most [Formula presented] vertices can be computed in O(nlogn) time. © 2021 Elsevier B.V

Numerical Modelling of Caseless Ammunition with Coreless Bullet in Internal Ballistics

In the search of a new weapon for combat in short range, it is proposed the use of a new experimentally designed 7.62 mm calibre ammunition with a lighter weight (caseless-coreless). This can be used in carbine assault rifles with short barrel or pistols. In this work, the compressible gases flowing through the gun barrel caused by the proposed ammunition were experimentally and numerically analysed. The Large Eddy Simulation was used for the numerical simulation, considering a compressible and turbulent flow, with the chemical species transport model and a complete conversion of the propellant reaction. Variations in pressure and temperature were compared with the results obtained from a conventional 7.62 mm full metal jacket (FMJ) ammunition. Results of ballistic experimental tests and numerical simulations were similar than those of the 9 mm x 19 mm FMJ ammunitions, showing feasibility for the development of new weapons intended for operations of short range shots.Defence Science Journal, Vol. 65, No. 3, May 2015, pp.203-207, DOI: http://dx.doi.org/10.14429/dsj.65.851

Author Correction: Increased lactate dehydrogenase activity is dispensable in squamous carcinoma cells of origin.

The original version of this Article contained an error in the spelling of the authors J. H. Joly and N. A. Graham, which were incorrectly given as J. Jolly and N. Graham. Additionally, the affiliation of both authors with 'Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089' and N. A. Graham with 'Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089' was inadvertently omitted. This has now been corrected in both the PDF and HTML versions of the Article

Numerical and Experimental Analysis of Sound Suppressor for a 5.56 mm Calibre

A sound suppressor is an internal or external device coupled to the barrel of a firearm. Its development has been historically related to the negative effects produced by the noise. This article presents the numerical and experimental analysis of a sound suppressor for a 5.56 mm caliber rifle. It was designed, manufactured, and tested inside a shooting tunnel for 911 m/s and 344 m/s velocities. Three geometric configurations with curved deflectors, conical deflectors, and finally with a reactive spiral capable of dissipating the acoustic wave were compared considering reactive and dissipative systems. The attenuation of the sound inside the silencer depends directly on the reduction of the projectile wave velocity and the deflagration of the gases at the instant of firing. Then the MIL-STD-1474E standard was used to carry out the experiments. The results in the computational numerical simulation show an average value of 143 dB for the considered three models, the Sound Pressure Level in the reactive core model decreased by 25% with respect to other proposals, which have an average value of 141 dB. These results can be useful to improve in the design of sound suppressors based on the needs of the users and under the specific characteristics of each weapon ballistic.&nbsp

Presencia de paratuberculosis en rumiantes en el estado de Zacatecas a través de estudio histopatológico

This study aimed to determine the presence of histopathological lesions suggestive of Mycobacterium avium subspecies paratuberculosis in ruminants with clinical field manifestations of paratuberculosis in the Mexican state of Zacatecas. Sixteen sheep, five goats, and four cattle from the municipalities of Morelos, Enrique Estrada, Jerez de García Salinas, Víctor Rosales, Fresnillo, Saín Alto, and Tepetongo were examined. The animals ranged in age from 5 weeks to 4 years. At necropsy, representative samples were taken from organs such as the small intestine, ileocecal valve, and mesenteric lymph nodes, for the routine histological technique of hematoxylin and eosin (HE). Subsequently, the Ziehl-Neelsen (ZN) technique was performed. It was observed that 56% of the animals were positive for acid-fast bacilli (AFB), compatible with Mycobacterium avium subspecies paratuberculosis. Eighty percent of the cases came from goats and 62.5% from sheep. 58.3% of females of both species showed lesions suggestive of paratuberculosis, and there was no significant difference in males. The lesions observed in the intestine were: proliferative enteritis in 78.6% of the cases, in the jejunum, enteritis, and necrosis in 21.4% of the cases, in the ileum, proliferative enteritis in 100% of the cases and 57.1% of lymph nodes were lymphadenomegalic and 50% of the cases in of the cases contained an inflammatory infiltrate in. In the state of Zacatecas, there is complete lack of studies that have detected the presence of paratuberculosis in any species, despite its economic and health importance.El presente estudio tuvo como objetivo determinar la presencia de lesiones histopatológicas sugestivas de Mycobacterium avium subespecie paratuberculosis en rumiantes con manifestaciones clínicas de campo de paratuberculosis en el estado mexicano de Zacatecas. Se examinaron 16 ovinos, 5 caprinos y 4 bovinos de los municipios de Morelos, Enrique Estrada, Jerez de García Salinas, Víctor Rosales, Fresnillo, Saín Alto y Tepetongo. La edad de los animales osciló entre 5 semanas y 4 años. En la necropsia se tomaron muestras representativas de órganos tales como intestino delgado, válvula ileocecal y ganglios linfáticos mesentéricos, para la técnica histológica de rutina de hematoxilina y eosina (HE). Posteriormente, se realizó la tinción de Ziehl-Neelsen (ZN). Se observó que el 56% de los animales eran positivos para bacilos ácido-alcohol resistentes (BAAR), compatibles con Mycobacterium avium subespecie paratuberculosis. El 80% de casos procedían de cabras y el 62.5% de ovejas. El 58.3% de las hembras de ambas especies presentaban lesiones sugestivas de paratuberculosis, y no había diferencias significativas en los machos. Las lesiones observadas en el intestino fueron: enteritis proliferativa en el 78.6% de los casos, en el yeyuno, enteritis y necrosis en el 21.4% de los casos, en el íleon, enteritis proliferativa en el 100% de los casos y el 57.1% de los ganglios linfáticos eran linfadenomegálicos y el 50% de los casos contenían un infiltrado inflamatorio. En el estado de Zacatecas se carece por completo de estudios que hayan detectado la presencia de paratuberculosis en alguna especie, a pesar de su importancia económica y sanitaria

Parallel evolution of vgsc mutations at domains IS6, IIS6 and IIIS6 in pyrethroid resistant Aedes aegypti from Mexico

Aedes aegypti is the primary urban mosquito vector of viruses causing dengue, Zika and chikungunya fevers –for which vaccines and efective pharmaceuticals are still lacking. Current strategies to suppress arbovirus outbreaks include removal of larval-breeding sites and insecticide treatment of larval and adult populations. Insecticidal control of Ae. aegypti is challenging, due to a recent rapid global increase in knockdown-resistance (kdr) to pyrethroid insecticides. Widespread, heavy use of pyrethroid spacesprays has created an immense selection pressure for kdr, which is primarily under the control of the voltage-gated sodium channel gene (vgsc). To date, eleven replacements in vgsc have been discovered, published and shown to be associated with pyrethroid resistance to varying degrees. In Mexico, F1,534C and V1,016I have co-evolved in the last 16 years across Ae. aegypti populations. Recently, a novel replacement V410L was identifed in Brazil and its efect on vgsc was confrmed by electrophysiology. Herein, we screened V410L in 25 Ae. aegypti historical collections from Mexico, the frst heterozygote appeared in 2002 and frequencies have increased in the last 16 years alongside V1,016I and F1,534C. Knowledge of the specifc vgsc replacements and their interaction to confer resistance is essential to predict and to develop strategies for resistance management