First record of elasmobranchs from the Lower Cretaceous of Argentina (Neuquén Basin)

The material reported herein comes from the Lower Cretaceous Agrio Formation (Neuquén Basin, west-central Argentina). These fishes dwelled in a Pacific Ocean embayment in southwestern Gondwana before the establishment of the Andean Cordillera. The material consists of an incomplete dorsal fin spine of the widespread Hybodontoidea clade (from upper Valanginian beds) and a partial tooth of one of the earliest known lamniforms (from upper Hauterivian beds).Facultad de Ciencias Naturales y Muse

Extraction and Characterization of Pectins From Peels of Criolla Oranges (<em>Citrus sinensis</em>): Experimental Reviews

The citriculture in the international field is important not only for its nutrient and vitamin characteristics but also for its valuable source of raw materials to obtain pectin, since it was found in the internal and external parts of the citrus peel. In our country, there are several varieties of orange, from which you can obtain by-products other than juice, such as essential oils, fertilizers, concentrates, and pectin. Pectin has different uses in the pharmaceutical industry for the preparation of suspensions, emulsions, cosmetics, capsules, etc. In the food industry, it is used as a film in packaging, thickener, and gelling agent in the manufacture of jellies and preserves, in wines as dehydrating plant tissues, in milk to precipitate casein, etc. The pectin extraction was carried out by basic or acid hydrolysis and then proceeds to purify and clarify. Once purified, the pectin was characterized in aqueous solution to determine its physicochemical properties such as molecular weight, hydrodynamic radius, hydration value, shape factor, etc. Thermal and mechanical characterizations were also performed, to assess its ability to form films

Dolomitized tidal cycles in the Agua de la Mula Member of the Agrio Formation (Lower Cretaceous), Neuquén Basin, Argentina

The Agrio Formation (Valanginian to early Barremian) is a siliciclastic and carbonate unit of the Neuquén Basin in west central Argentina. A conspicuous 20 m thick dolomitized section near the top of the upper Agua de la Mula Member of the Agrio Formation was identified for the first time in this unit. The analyzed section is composed of dolostones with scarce siliciclastic intercalations. A tidal flat environment with highfrequency cycles is suggested for the measured section. Petrography, SEM, X-Ray, EDAX and cathodoluminiscence analyses showed two different dolomitization processes. The first one comprises early mimetic and non mimetic dolomitization on ooids, bioclasts and early marine cements. The second one reveals precipitation of dolomite cement. The mimic dolomitization indicates that this process took place before the inversion from aragonite to calcite, or from low magnesium calcite to high magnesium calcite. The dolomitization should have been soon after the deposition. The presence of dolomite cement is probably related to a high concentration of Mg2+ coming from sea water flushing into highly porous sediments mixed with fresh waters from the continent. This is suggestive of a change of diagenetic environment from marine to meteoric, probably during sea level changes. A model that explains these processes is the shallow seawater dolomitization model. This model proposes that dolomitization is triggered by the drive of large amount of seawaters through the sediments

Determination of laser penetration in dentinal tubules

La anatomía de las piezas dentarias y principalmente la configuración interna de los conductos radiculares exigen que la terapia endodóntica tenga como objetivo principal logra una correcta desinfección del sistema de canales radiculares a través de la eliminación de bacterias, toxinas y barro dentinario. Se realizará el tratamiento endodóntica en piezas extraídas, necróticas y enmarcadas dentro de los criterios de inclusión y exclusión que estipula el proyecto. se dividirán las piezas en tres grupos, un primer grupo testigo al que solo se le realizará el acceso cameral para luego ser observados al microscopio, otro al que se le aplicará el protocolo de limpieza y conformación convencional y el último al que se le aplicara el protocolo convencional más la aplicación de láser de diodo de baja frecuencia. Luego se realizará la observación al microscopio electrónico buscando demostrar que con la aplicación del láser de diodo de baja frecuencia por una mayor penetración del láser en los túbulos dentinarios. Se pretende concluir que la utilización del láser como complemento de la limpieza redundará en un aumento significativo de la tasa de éxito de la terapia endodóntica.The complex anatomy of the teeth and mainly the internal configuration of the root canals require that endodontic therapy has as its main objective to achieve a correct disinfection of this root canal system through the elimination of bacteria, toxins and dentin sludge. Endodontic treatment will be performed on extracted, necrotic pieces and framed within the inclusion and exclusion criteria stipulated by the project. The pieces will be divided into three groups, a first control group to which only the cameral access will be performed and then be observed under the microscope, another to which the conventional cleaning and shaping protocol will be applied and the last to which the conventional protocol plus the application of low frequency diode laser. Then an electron microscope observation will be carried out, seeking to demonstrate that with the application of a low frequency diode laser it is possible to increase the effectiveness of endodontic disinfection, favored by a greater penetration of the laser in the dentin tubules. It is intended to conclude that the use of laser as a complement to cleaning will result in a significant increase in the success rate of endodontic therapy.Facultad de Odontologí

Determination of laser penetration in dentinal tubules

Para lograr una correcta desinfección del sistema de canales radiculares es fundamental que la terapia endodóntica tenga como objetivo principal la eliminación de bacterias, toxinas y barro dentinario. La anatomía compleja de las piezas dentarias y principalmente la configuración interna de los conductos radiculares dificulta alcanzar este objetivo. En este trabajo se realizará la preparación endodóntica en piezas extraídas enmarcadas dentro de los criterios de inclusión y exclusión que estipula el proyecto y se dividirán en tres grupos, un primer grupo testigo al que no se le realizara tratamiento alguno, otro al que se le aplicara el protocolo de limpieza y conformación convencional y el ultimo al que se le aplicara el protocolo convencional más la aplicación de laser de diodo de baja frecuencia. Luego serán seccionados y acondicionados para su observación al microscopio electrónico de barrido, buscando demostrar que con la aplicación del láser de diodo de baja frecuencia es posible elevar la efectividad de la desinfección del endodonto, favorecida por una mayor penetración del láser en los túbulos dentinarios. Se pretende concluir que la utilización del láser como complemento de la limpieza redundara en un aumento significativo de la tasa de éxito de la terapia endodóntica.In order to achieve a correct disinfection of the root canal system, it is essential that endodontic therapy has as its main objective the elimination of bacteria, toxins and toothpaste. The complex anatomy of the teeth and mainly the internal configuration of the root canals makes it difficult to achieve this objective. In this work, the endodontic preparation will be carried out in extracted pieces framed within the inclusion and exclusion criteria stipulated by the project and will be divided into three groups, a first control group to which no treatment will be performed, another to which it will be applied the conventional cleaning and shaping protocol and the last one to which the conventional protocol plus the application of a low frequency diode laser will be applied. They will then be sectioned and conditioned for observation under a scanning electron microscope, seeking to demonstrate that with the application of a low-frequency diode laser it is possible to increase the effectiveness of endodontic disinfection, favored by a greater penetration of the laser in the dentin tubules. It is intended to conclude that the use of laser as a complement to cleaning will result in a significant increase in the success rate of endodontic therapy.Facultad de Odontologí

Determination of laser penetration in dentinal tubules

La terapéutica odontológica estableció desde sus comienzos en 1838, una relación fundamental con la anatomía dentaria interna y los procesos de limpieza y ensanche ductal. Por lo tanto, el objetivo principal de la terapia endodóntica es lograr la desinfección del sistema de conductos radiculares a través de la eliminación de bacterias, toxinas y barro dentinario. Se realizara la limpieza del interior ductal en piezas extraídas necróticas, que serán divididas en tres grupos, uno testigo al que no se le hará tratamiento alguno solo acceso cameral y observación al microscopio; otro al que se le aplicara un protocolo convencional de tratamiento de conducto y otro con protocolo convencional y laser de diodo de baja frecuencia para poder evidenciar la influencia directa del láser en una mejor preparación sin barro dentinario y por ende sin biofilm. Dichas observaciones se harán con microscopia electrónica y con ello se pretende demostrar que con una aplicación de laser de diodo de baja frecuencia es posible elevar la efectividad de la limpieza del endodonto precisamente más en profundidad del túbulo. Se pretende concluir con un aumento significativo en la tasa de éxito en la terapéutica endodóntica incorporando de manera sinérgica a la irrigación la emisión laser.Dental therapy established since its inception in 1838, a fundamental relationship between internal dental anatomy and the processes of cleaning and ductal widening. Therefore, the main objective of endodontic therapy is to achieve disinfection of the root canal system through the elimination of bacteria, toxins and smear layer. The cleaning of root canals will be carried out into necrotic extracted pieces, which will be divided into three groups, first a witness group that will be treated only by making cameral access and observation under the microscope; another one, where a conventional canal treatment protocol will be applied and a last group, treated with conventional protocol and low frequency diode laser to be able to demonstrate the direct influence of the laser in a better preparation without smear layer and therefore without biofilm. Such observations will be made with electron microscopy and with this study it is intended to demonstrate that with a low frequency diode laser application it is possible to increase the effectiveness of the endodontic cleaning and precisely more in depth of the dentinal tubules. It is intended to conclude that a significant increase in the success rate in endodontic therapy is possible by incorporating laser emission synergistically to irrigation.Facultad de Odontologí

The Laser In Endodontics A Tool Full Of Advantages

Introducción: La endodoncia previene y trata las enfermedades del endodonto, región apical y periapical Para eso debe eliminarse el contenido del interior de los conductos radiculares El smear layer posee una capacidad de penetración en la dentina de 40 mieras, las bacterias pueden colonizar hasta una profundidad de 1,100 mieras, mientras que el Hipodorito de Sodio, imigante más utilizado por su alta eficacia desinfectante, solo posee un poder de penetración de 130 micrómetros dentro de los túbulos Actualmente, se sugiere la imple mentación del Láser para lograr la desinfección del sistema de conductos como un co-adyuvante del tratamiento endodóntico tradicional. El Láser puede ser implementado con estos objetivos mediante dos técnicas, la desinfección fotoactivada (PAD) y la desinfección fotoacústica (PIPS) y a su vez como bioestimulante de los tejidos blandos. Objetivos: Teniendo en cuenta los datos expuestos, este trabajo de investigación se propone evaluar el poder de penetración del Láser en el interior de los túbulos dentinarios.Introduction: Endodontics prevents and treats endodontic, apical and periapical diseases. For this, the content of the interior of the root canals must be removed. The smear layer has a penetration capacity of 40 microns into the dentin, bacteria can colonize up to a depth of 1.100 microns, while Sodium Hypochlorite, the most widely used irrigant forits high disinfection efficiency, it only has a penetration power of 130 micrometers inside the tubules. Currently, the implementation of the laser is suggested to achieve the disinfection of the canal system as a co-adjuvant of the traditional endodontic treatment The laser can be implemented with these objectives through two techniques, photoactivated disinfection (PAD) and photoacoustic disinfection (PIPS) and in turn as a biostimulant of soft tissues. Objectives: Taking into account the data presented, this research work aims to evaluate the penetration power of the Laser inside the dentin tubules.Facultad de Odontologí

Determination of laser penetration in dentinal tubules

La terapéutica odontológica estableció desde sus comienzos en 1838, una relación fundamental con la anatomía dentaria interna y los procesos de limpieza y ensanche ductal. Por lo tanto, el objetivo principal de la terapia endodóntica es lograr la desinfección del sistema de conductos radiculares a través de la eliminación de bacterias, toxinas y barro dentinario. Se realizara la limpieza del interior ductal en piezas extraídas necróticas, que serán divididas en tres grupos, uno testigo al que no se le hará tratamiento alguno solo acceso cameral y observación al microscopio; otro al que se le aplicara un protocolo convencional de tratamiento de conducto y otro con protocolo convencional y laser de diodo de baja frecuencia para poder evidenciar la influencia directa del láser en una mejor preparación sin barro dentinario y por ende sin biofilm. Dichas observaciones se harán con microscopia electrónica y con ello se pretende demostrar que con una aplicación de laser de diodo de baja frecuencia es posible elevar la efectividad de la limpieza del endodonto precisamente más en profundidad del túbulo. Se pretende concluir con un aumento significativo en la tasa de éxito en la terapéutica endodóntica incorporando de manera sinérgica a la irrigación la emisión laser.Dental therapy established since its inception in 1838, a fundamental relationship between internal dental anatomy and the processes of cleaning and ductal widening. Therefore, the main objective of endodontic therapy is to achieve disinfection of the root canal system through the elimination of bacteria, toxins and smear layer. The cleaning of root canals will be carried out into necrotic extracted pieces, which will be divided into three groups, first a witness group that will be treated only by making cameral access and observation under the microscope; another one, where a conventional canal treatment protocol will be applied and a last group, treated with conventional protocol and low frequency diode laser to be able to demonstrate the direct influence of the laser in a better preparation without smear layer and therefore without biofilm. Such observations will be made with electron microscopy and with this study it is intended to demonstrate that with a low frequency diode laser application it is possible to increase the effectiveness of the endodontic cleaning and precisely more in depth of the dentinal tubules. It is intended to conclude that a significant increase in the success rate in endodontic therapy is possible by incorporating laser emission synergistically to irrigation.Facultad de Odontologí

Determination of laser penetration in dentinal tubules

Durante la terapia endodóntica es primordial lograr una correcta desinfección del sistema de canales radiculares, constituyéndose como objetivo principal del tratamiento endodóntico la eliminación de bacterias, toxinas y barro dentinario. La complejidad anatómica de las piezas dentarias y principalmente la configuración interna de los conductos radiculares compromete alcanzar este objetivo. Este trabajo busca demostrar que con la aplicación del láser de diodo de baja potencia es posible elevar la efectividad de la desinfección del endodonto, favorecida por una mayor penetración del láser en los túbulos dentinarios para lo cual al número de piezas extraídas enmarcadas dentro de los criterios de inclusión y exclusión que estipula el proyecto , se las dividió en tres grupos, un primer grupo testigo al que no se le realizo tratamiento alguno, otro al que se le aplico el protocolo de limpieza y conformación convencional y el ultimo al que se le aplico el protocolo convencional más la aplicación de laser de diodo de baja frecuencia. Luego fueron seccionados y acondicionados para su observación al microscopio electrónico de barrido. Se pretende concluir que la utilización del láser como complemento de la limpieza redundara en un aumento significativo de la tasa de éxito de la terapia endodóntica.During endodontic therapy it is essential to achieve correct disinfection of the root canal system, the main objective of endodontic treatment being the elimination of bacteria, toxins and dentin smear. The anatomical complexity of the dental pieces and mainly the internal configuration of the root canals compromises achieving this objective. This work seeks to demonstrate that with the application of low power diode laser it is possible to increase the effectiveness of endodontic disinfection, favored by a greater penetration of the laser in the dentinal tubules for which the number of extracted pieces framed within the criteria of inclusion and exclusion stipulated by the project, they were divided into three groups, a first control group to which no treatment was carried out, another to which the conventional cleaning and conformation protocol was applied and the last to which was applied the conventional protocol plus the application of low frequency diode laser. They were then sectioned and conditioned for observation under a scanning electron microscope. It is intended to conclude that the use of laser as a complement to cleaning will result in a significant increase in the success rate of endodontic therapy.Facultad de Odontologí