A Comprehensive Survey on Resource Allocation Strategies in Fog/Cloud Environments.

The growing number of connected objects has allowed the development of new applications in different areas. In addition, the technologies that support these applications, such as cloud and fog computing, face challenges in providing the necessary resources to process information for different applications due to the highly dynamic nature of these networks and the many heterogeneous devices involved. This article reviews the existing literature on one of these challenges: resource allocation in the fog-cloud continuum, including approaches that consider different strategies and network characteristics. We also discuss the factors influencing resource allocation decisions, such as energy consumption, latency, monetary cost, or network usage. Finally, we identify the open research challenges and highlight potential future directions. This survey article aims to serve as a valuable reference for researchers and practitioners interested in the field of edge computing and resource allocation.

A DFT study of addition reaction between fragment ion (CH2) units and fullerene (C60) molecule.

The theoretical study of the interaction between CH(2) and fullerene (C(60)) suggests the existence of an addition reaction mechanism; this feature is studied by applying an analysis of electronic properties. Several different effects are evident in this interaction as a consequence of the particular electronic transfer which occurs during the procedure. The addition or insertion of the methylene group results in a process, where the inclusion of CH(2) into a fullerene bond produces the formation of several geometric deformations. A simulation of these procedures was carried out, taking advantage of the dynamic semi-classical Born-Oppenheimer approximation. Dynamic aspects were analyzed at different speeds, for the interaction between the CH(2) group and the two bonds: CC (6, 6) and CC (6, 5) respectively on the fullerene (C(60)) rings. All calculations which involved electrons employed DFT as well as exchange and functional correlation. The results indicate a tendency for the CH(2) fragment to attack the CC (6, 5) bond.

DFT: a dynamic study of the interaction of ethanol and methanol with platinum.

The interaction between alcohol molecules and platinum (Pt) was studied using molecular dynamics (MD; Born-Oppenheimer method). Alcohol molecules like ethanol and methanol present a similar molecular structure, with a methyl group (CH(3)) at one end and a fragment of hydroxyl (OH) at the other. This fact generates two orientations that are considered in the interaction with Pt. The MD calculation results for these two orientations indicate a preferential orientation due to energy interactions. A plausible reaction mechanism that takes into account the interaction between Pt and alcohol is presented. The charge transference obtained from the Pt-alcohol interaction was also analyzed. The energy for the two orientations was calculated by indicating the preferential orientation. The methyl and hydroxyl groups are involved in heterolytic breakage of hydrogen bonds, joined to a carbon atom in the former and to an oxygen atom in the latter; however, the methyl group reaction seems to be the most important.

Localized gingival recessions treated with the original envelope technique: a report of 50 consecutive patients.

BACKGROUND: The surgical techniques used to treat gingival recession have changed considerably in the last 50 years. The envelope technique described nearly 20 years ago still offers an excellent alternative for the problem of recession. The purpose of this retrospective study is to show the results of 115 recession sites treated in 50 patients using the envelope technique. METHODS: One hundred-fifteen consecutive procedures were performed in 50 patients in a private practice in the last 5 years using the envelope technique. Briefly, the teeth are scaled, a split thickness flap is performed around the recession, a subepithelial connective tissue graft is harvested from the palate and placed over the recession, and sutured with 6-0 silk. Four cases representing different types of recession will be reviewed and all cases will be analyzed. RESULTS: In general, this surgical method provided excellent root coverage and an increased amount of keratinized gingiva. The complete root coverage mean was 85%, 65%, and 16% for recession Class I, II, and IV, respectively. CONCLUSION: The cases support the use of the envelope technique to treat different types of single and multiple recessions.

Immediate replacement of single upper posterior teeth: a report of cases.

BACKGROUND: The immediate replacement of upper molar teeth with implants poses a significant challenge to the clinician because of its sinus involvement. PURPOSE: The purpose of this article is to report a protocol in which single molar teeth are replaced immediately with implants, minimizing the need for other surgical procedures. MATERIALS AND METHODS: This protocol has been employed in eight cases. Briefly, the teeth are extracted atraumatically, the sockets evaluated, an osteotomy performed following the direction of the socket, and a wide diameter implant placed using the socket walls and sinus floor to anchor it. A grafting material is placed when the space between implant and socket wall is considerably large. Three cases are reviewed here, and all eight are summarized. RESULTS: All cases have excellent soft and hard tissue healing after 6 months. Furthermore, the overall time needed to restore the cases has been considerably reduced and the need for sinus management eliminated. CONCLUSION: The cases presented support the use of the described protocol in the placement of implants in maxillary molar areas without any other sinus procedures.

Isquemia miocárdica producida por el origen anómalo de la arteria coronaria descendente anterior: caso clínico / Myocardial ischemia produced by anomalous origin of the anterior descending coronary artery: clinical case

Se presenta un raro caso de anomalía de origen coronario en el cual la arteria descendente anterior se originaba en forma normal en su tercio inicial; sin embargo no sucedía así con su segmento medio y distal, que nacía del seno coronario derecho transcurriendo entre la arteria aorta y la pulmonar. Si bien en este caso no existían lesiones estenosantes, dicha anomalía causaba isquemia miocárdica, la que fue resuelta quirúrgicamente

Preservation of esthetics with implant dentistry: a clinical report.

BACKGROUND: The replacement of single teeth with implants in the anterior maxilla poses a significant challenge to the clinician because of its esthetic implications. PURPOSE: The purpose of this article is to report a protocol in which single teeth are replaced by implants and temporarily restored without load, immediately after extraction. MATERIALS AND METHODS: Between June 2001 and July 2002, 16 cases were followed up in which this protocol was used. Briefly, the teeth are extracted with a Periotome (Friadent, Mannheim, Germany), using a flapless technique, the sockets are evaluated and débrided, an osteotomy is performed following the direction of the socket, and a tapered implant is placed using the alveolar crest as the landmark. A temporary abutment is immediately custom made, and a temporary crown is placed without loading. The 16 cases are summarized, and 4 of them are presented to illustrate this approach. RESULTS: All four cases have provided excellent esthetic results maintaining an ideal implant-to-supporting-tissue relationship. Furthermore, the overall time needed to restore the cases was considerably reduced when compared with time needed for the conventional approach. CONCLUSION: The four cases presented support the use of the described protocol in the placement of single implants in areas of the maxillary anterior region where esthetics is a high priority.

Anti-tick effect observed in mature plants of tropical legumes stylosanthes humilis and stylosanthes hamata

El efecto anti-garrapata de plantas maduras de las leguminosas tropicales stylosanthes humilis y stylosanthes hamata, fue evaluado en parcelas experimentalmente infestada con larvas de garrapata boophilus microplus, utilizando al pasto cenchurus ciliaris como tratamiento testigo. El efecto fue evaluado contando el número total de larvas vivas recuperadas de las parcelas experimentales por la técnica de bandera de doble recorrido durante un periodo de cuatro semana. El efecto anti-garrapata observado en ambas especies de stylosanthes no mostró diferencias entre ellas (p<0,05), el porcentaje de sobrevivencia de larvas fue del 5,1 por ciento para S. hamata. En la primera especie el efecto anti-garrapata fue menor que el reportado en plantas jóvenes, pero en S. hamata este efecto fue similar en plantas maduras y jóvenes. Es necesario realizar más estudios para complementar el conocimiento que tiene acerca de estas plantas y establecer su uso en condiciones de campo

Expresión génica del sistema renina-angiotensina en cardiomiocitos ventriculares de rata adulta / Genic expression of renin-angiotensin system in ventricular cardiomyocites in adult rats

Se ha postulado la existencia de un sistema renina-angiotensina (SRA) intracardíaco funcional que explica las acciones tróficas de la angiotensia II (AII) sobre las distintas poblaciones celulares, así como la acción preventiva y regresiva de distintos fármacos en la hipertrofia ventricular hipertensiva o secundaria al infarto del miocardio. En este estudio hemos determinado la expresión génica de los componentes del SRA en cardiomiocitos ventriculares de corazón de rata adulta, aislados por perfusión retrógrada con proteasas. La expresión de los RNA mensajeros (mRNA) para angiotensinógeno, renina, enzima convertidora (ECA) y receptor subtipo AT-1 para AII (AT-1R), se evaluó a través de la técnica de transcripción reversa asociada a la reacción en cadena de la DNA polimerasa (RT-PCR), usando oligonucleótidos partidores específicos. El procedimiento de aislamiento celular permitió obtener una población enriquecida de cardiomicitos ventriculares viables (> 95 por ciento), los cuales presentaron actividad contráctil espontánea e inmunorreactividad a anticuerpos dirigidos a proteínas específicas del cardiomiocito. En estas células y en tejidos controles (hígado, riñón y pulmón) se detectaron los mRNA para angiotensinógeno, renina, ECA y AT-1R. Se concluye que los cardiomiocitos ventriculares de rata expresan todos los genes esenciales del SRA,confirmando la existencia de este sistema intracardíaco. Igualmente, la implementación de estas metodologías permitirán estudiar in vitro la regulación del SRA local bajo condiciones fisiológicas y patológicas

Medida de torçäo femoral pelo ultra-som: comparaçäo com o método radiográfico biplanar / The measurement of femoral anteversion using ultrasound and biplanar radiographic methods

Em 19 indivíduos foi medido o ângulo de torçäo femoral de ambos os fêmures pelo método ultra-sonográfico. Os resultados foram comparados com os valores obtidos pela técnica radiológica biplanar em 12 desses indivíduos. Näo se encontrou correspondência precisa entre os valores angulares para cada paciente com os dois métodos. Concluímos que, nas condiçöes experimentais empregadas, o método ultra-sonográfico näo se apresentou com precisäo suficiente para recomendá-lo para aplicaçäo clínica