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The increase in the global demand for energy and fossil fuel dependency is hindering efforts to reduce greenhouse gas (GHG) emissions. Geothermal resources supplement this increase in energy demand with reduced emissions because of their availability, base-load production profile, and climatic independence. Despite these advantages, the development of geothermal energy is limited because of different reasons such as subsurface exploration risk and high upfront capital cost for drilling and facility construction. However, similarities in infrastructure and operations between the oil and gas industry and the geothermal industry can optimize expense and development when exploiting geothermal resources. Thus, in this review, we present recent advances and applications of geothermal power systems in the oil and gas industry starting from the fundamentals and basic principles of geothermal energy and the organic Rankine cycle (ORC). These applications include the use of geothermal resources via abandoned wells, active wells, and paired thermal enhanced oil recovery processes with injection for fluid heating and energy production. Abandoned wells are alternatives that reduce costs in geothermal energy-use projects. The use of geothermal resources via active wells allows the valorization of a resource, such as the production of water, which is considered a byproduct of production activities in an oilfield. The use of thermally enhanced oil recovery processes enhances the energy conditions of fluids produced in the field, improving geothermal systems with fluids at higher temperatures. Finally, an overview is presented of the challenges and opportunities of geothermal energy in the oil industry where the requirement to improve the usage of technologies, such as the ORCs, with the working fluids used in the cycles, is highlighted. Furthermore, the importance of environmental studies and use of novel tools, such as nanotechnology, to improve the efficiency of geothermal energy usage is highlighted.

Si bien desde la constitución política de 1991 Colombia a realizado grandes a avances en materia de protección de derechos, hay un aspecto en el derecho de familia que ha sido desatendido: la familia plural. Esta figura, compuesta por las esferas de la poligamia y la pluriparentalidad, ya ha visto importantes avances en otros ordenamientos jurídicos, como lo son Brasil, Canadá y Estados Unidos; países que, ya sea por medio de una ley o mediante un precedente judicial, han logrado presentar una discusión que, con argumentos como la socioafectividad, o el mayor interés del menor, se han visto resueltas en la aceptación de estas figuras en sus ordenamientos. Es momento de que, como lo hicieron estos países, Colombia empiece una discusión argumentada sobre el tema.

Introducción: La producción de pollo de engorde es de gran interés para el departamento de Santander dada su alta participación dentro del PIB pecuario, lo que lo constituye en el principal centro avícola nacional. Es importante conocer las condiciones bajo las cuales se realiza la producción de pollo de engorde e identificar el potencial que tienen estos sistemas de producción. Objetivo: caracterizar los sistemas de producción industrial de pollo de engorde ubicados en el departamento de Santander. Materiales y métodos: Para el desarrollo del trabajo se contó con información proveniente de 79 predios avícolas los cuales se encontraban ubicados en 4 provincias: Metropolitana, Soto, Guanentá y Yariguíes. Se realizó un análisis de clúster y se generó un índice de adopción tecnológica. Resultados: Se encontró que existe variación en la adopción de tecnologías, siendo las más frecuentes las tecnologías blandas. Santander obtuvo un índice de adopción tecnológica bajo. Conclusiones: El sector avícola del departamento de Santander posee un bajo índice de adopción tecnológica, lo cual sugiere la necesidad de evaluar el efecto que esto tiene sobre los resultados productivos con miras al incremento de la productividad a largo plazo en la zona

Spring systems are efficient and fast precipitating non‐marine carbonate factories, but they are also prone to (early) diagenesis. Evidence of diagenesis in travertines remains controversial as the resulting textures have been considered primary in other deposits and the impact on geochemical/palaeo‐environmental signals is often poorly addressed. This study revisits the Y‐10 core, taken in 1967 at one of the upper terraces of Mammoth Hot Springs in Yellowstone National Park (USA). The travertine depositional facies in the upper 50 m of the core show a general distal to proximal facies trend upwards. To unravel the nature, impact and timing of early diagenesis, fabrics and geochemical signatures are also compared to modern hot spring carbonates. Secondary ion mass spectrometry and detailed microscopy proved powerful in determining the stable isotope signature of different cement generations, thereby detangling the fluid history. Diagenesis starts during spring activity, but these warm waters not only precipitate CaCO3 at the top, they also seem to have circulated through the porous spring fabrics below. It resulted in coarsening and homogenization of the primary textures through neomorphism of aragonite and calcite cementation, often resulting in new intracrystalline microporosity within the calcite crystals. Subsequent circulation of meteoric fluids led to dissolution and cementation, particularly near the top of the core. Careful interpretation of U/Th dates suggests that travertine deposition started at the beginning of the Holocene/end Pleistocene. Calculated depositional (precipitation) rates vary between 2 and 20 mm/year, assuming a constant rate between samples at different depths. Aragonite deposits are completely transformed to calcite below depths of 5–10 m, corresponding to a time span of 4,000 years. Core and petrography observations, together with dating, suggest that travertine strata below marine sandstones in the lower part of the core may relate to fault displacement after the onset of travertine deposition.

The start-up, build-up and demise of cold-water coral mounds are governed by environmental changes at global, regional and local scales. Whilst the formation of cold-water coral mounds across the globe is widely documented to follow interglacial-glacial cycles, less is known about their response to local environmental fluctuations during short time intervals. This study investigates the local variations in coral mound build-up along Brittlestar Ridge I (East Melilla Coral Province, Southeast Alboran Sea) by comparing three on-mound gravity cores collected ∼1 km apart, together with five previously described on-mound records, along a longitudinal transect on the ridge crest. Radiocarbon foraminiferal dating associated to U-series coral dating allowed to correlate the different records and to estimate mound aggradation rates, whilst grain-size analysis provided information on bottom current velocities. Prior to a rapid period of coral mound build-up initiated at ∼14.75 ka BP, the three cores present an occurrence of cm-thick bryozoan-dominated intervals nearly entirely consisting of the erect cheleistome Buskea dichotoma. Offsets between benthic foraminiferal and coral ages suggest that older dead allochtonous benthic foraminifera are possibly eroded from neighbouring settings, transported and deposited within the coral framework. In contrast, younger benthic foraminifera would develop on dead coral framework during periods of reef stagnation. The comparison of all cores indicates that mound build-up along the ridge did not follow the same timing during the last ∼16 kyr and that mound aggradation was marked by a staggered dynamic. Both local differences in bottom current velocities and patchiness of other key environmental actors (e.g. substrate availability) are suspected to drive the observed staggered mound build-up. Cold-water coral mound build-up shows important differences during Greenland Interstadial 1 (i.e. the Bølling-Allerød) and the Holocene, hence examplifying how local environmental variability may overprint global and regional climate variability over short time periods., Marine Geology, 457, ISSN:0025-3227

Objective: The objective of this study was to observe the effect that 3% Sodium Hypochlorite and 17% Ethylenediamine Tetraacetic Acid (EDTA) with water in between, used sequentially and individually had in the disinfection of dentin blocks that were contaminated with Enterococcus faecalis. Materials and Methods: Thirty apical and coronal dentin block samples were divided into five groups (n=5): All samples were inoculated with Enterococcus faecalis Group 1: Samples were submerged in 3% NaOCl then in 17% EDTA. Group 2: Samples were submerged first in 17% EDTA and then in 3% NaOCl. Group 3: Samples were immersed in 3% NaOCl only. Group 4: Samples were submerged in 17% EDTA only. Group 5 (positive control group): Samples were only submerged in distilled water. All samples were submerged in distilled water after each irrigation cycle. The irrigation protocol was repeated in all groups until all dentin samples were exposed to 24ml of the irrigating solutions. CFU units were counted and classified in an ordinal scale and compared with the linear-by-linear association test. Results: A significant linear trend in the reduction of CFU was observed when NaOCl and EDTA were combined (independently of the sequence used) when compared to groups 3 and 4 where the irrigants were used individually both in coronal (p=9.45 x 10-21), and apical slices (p=2.33 x 10-20). NaOCl was significantly more effective than EDTA in both coronal and apical slices (p ≥ 0.000001) when used alone. Conclusion: 3% Sodium Hypochlorite was more effective than 17% EDTA. However, alternating 3% NaOCl with 17% EDTA resulted in better dentinal disinfection. Clinical Relevance: Establishing an irrigation protocol that is effective in eradicating bacteria entrenched in dentinal tubules can lead to a more successful outcome in endodontically treated teeth.

Chitin and its derived products have great potential in various industries, such as biomedical, pharmaceutical, food, among others, due to its biodegradability, biocompatibility, null toxicity, and...

We study the elliptic genera of the non-critical strings of six dimensional superconformal field theories from the point of view of the strings' worldsheet theory. We formulate a general ansatz for these in terms of characters of the affine Lie algebra associated to the 6d gauge group at negative level, and provide ample evidence for the validity of this ansatz for 6d theories obtained via F-theory compactification on elliptically fibered Calabi-Yau manifolds over a Hirzebruch base. We obtain novel closed form results for many elliptic genera in terms of our ansatz, and show that our results specialize consistently when moving along Higgsing trees., 45 pages, many tables; v2: typos corrected, new closed form results for the elliptic genera of a B4 and an E7 theory conjectured

Tires, bitumen, and road markings are important sources of traffic-derived carbonaceous wear particles and microplastic (MP) pollution. In this study, we further developed a machine-learning algorithm coupled to an automated scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX) analytical approach to classify and quantify the relative number of the following subclasses contained in environmental road dust: tire wear particles (TWP), bitumen wear particles (BiWP), road markings, reflecting glass beads, metallics, minerals, and biogenic/organics. The method is non-destructive, rapid, repeatable, and enables information about the size, shape, and elemental composition of particles 2–125 µm. The results showed that the method enabled differentiation between TWP and BiWP for particles > 20 µm with satisfying results. Furthermore, the relative number concentration of the subclasses was similar in both analyzed size fractions (2–20 µm and 20–125 µm), with minerals as the most dominant subclass (2–20 µm x̄ = 78%, 20–125 µm x̄ = 74%) followed by tire and bitumen wear particles, TBiWP, (2–20 µm x̄ = 19%, 20–125 µm x̄ = 22%). Road marking wear, glass beads, and metal wear contributed to x̄ = 1%, x̄ = 0.1%, and x̄ = 1% in the 2–20-µm fraction and to x̄ = 0.5%, x̄ = 0.2%, and x̄ = 0.4% in the 20–125-µm fraction. The present results show that road dust appreciably consists of TWP and BiWP within both the coarse and the fine size fraction. The study delivers quantitative evidence of the importance of tires, bitumen, road marking, and glass beads besides minerals and metals to wear particles and MP pollution in traffic environments based on environmental (real-world) samples

En la actualidad las instituciones sociales tradicionales, tales como la familia, la religion, el Estado y la ciudad, se han revelado como estructuras llenas de contradicciones y fisuras internas manifestadas en la exclusion, la represion y la segregacion socio espacial que padecen millones de personas. Ante esta realidad incierta es dificil no buscar explicaciones que den cuenta de las razones para que el mundo se presente de esa forma. Las respuestas a este fenomeno se han dado desde la filosofia, la sociologia, la historia, entre otras disciplinas. Para este texto esperamos exponer como dicha realidad se puede comprender a partir de la interrelacion de dos dimensiones de lo humano nombradas por Gilles Deleuze y Felix Guattari[1] como lo liso y lo estriado. Lo liso corresponde a la realidad conformada por lo caotico, por lo que no puede ser medido ni cuantificado, por aquello que se da sin regulaciones racionales y que existe espontaneamente en la incertidumbre del devenir cotidiano. Lo estriado, por su parte, hace referencia a la realidad regulada, planeada y racionalizada, que se constituye por medio de la cuantificacion, el control y la consolidacion de un mundo previsible. Bajo esta premisa, y si tenemos en consideracion que el diseno es una actividad que se ubica en el limite entre la reflexion y la produccion material de objetos que intermedian en las practicas humanas, consideramos que existe la posibilidad de establecer puentes entre las interpretaciones filosoficas, existenciales y politicas y el quehacer del diseno, respondiendo a traves del lenguaje a nuestras propias inquietudes y aproximaciones conceptuales de nuestro quehacer como disenadores. Para hacer entonces explicita esta conexion nos valdremos de la experiencia vivida en el Laboratorio de Diseno Reforma (Medellin, Colombia) con el proyecto Fisuras y resquicios, en el que se desarrollaron objetos de uso diario elaborados por medio de la ceramica como tecnica propicia para la exploracion de texturas y formas dentro de un lenguaje visual que sintetiza lo provechoso de entender los resquicios y las fisuras sociales como espacios propicios para el desenvolvimiento de lo diverso y lo multiple. [1] Se hace referencia a las ideas desarrolladas por estos dos autores en su texto Mil mesetas. Capitalismo y esquizofrenia, publicado por la editorial Pre-textos en el ano 2004 en Valencia, Espana.

The localized compressive deformation (LCD) effect generated by an indentation process at the crack tip on the fatigue crack growth of the 7075-T651 aluminum alloy is reported. Eccentrically loaded single-edge crack tension specimens (ESE(T)) were pre-cracked at a crack length of about 20 mm by applying a constant amplitude fatigue loading. Subsequently, the LCD process was performed by using a semi-spherical indenter with a radius of 16 mm to compress the crack tip zone at different forces (5.0, 7.0, 12.5, 13.5, 15.5 kN), applied on the opposite surfaces of the specimens. The fatigue cracking process was continued on the compressed samples until an overall crack length of about 30 mm was obtained. The compressive load and the number of delayed cycles is discussed in terms of crack length and crack tip opening displacement (CTOD). A direct relationship between the compressive force induced by the LCD process and the delay of the crack propagation due to the crack arrest was observed. This effect became evident at a compressive force of 5.0 kN, where the crack propagation was arrested for about 9000 cycles in comparison with the non-LCD sample. However, when the force increased, the crack arrest also increased. The crack was considered to be completely arrested at a compressive load of 15.5 kN, since the crack did not grow after the application of more than 3 × 106 cycles.

In the oil and gas industry, there has not been a consistent, concerted effort to reduce global greenhouse gas (GHG) emissions across the supply chain. In addressing this challenge, this study evaluates the potential GHG emissions reduction that may be realized through deployment of a geothermal power co-production system in two Colombian oil fields, compared to a base case where energy needs are derived through non-renewable sources such as gas and diesel. These geothermal power co-production systems make use of organic Rankine cycle (ORC) engines to convert the heat from produced oilfield fluids into electrical energy. The energy potential of this resource is evaluated through the exergy concept, and a life cycle analysis is implemented to calculate the carbon footprint using the Intergovernmental Panel on Climate Change (IPCC) 2013 methodology. In the two oil fields of interest, OFA and OFB, the results show a maximum potential energy production of 2260 kWe for OFA and 657 kWe for OFB. The co-production of crude oil and electrical energy from geothermal resources suggests a possible a carbon footprint reduction of 19% and 11% for OFA and OFB, respectively, when compared to conventional power systems. In addition, four emissions scenarios are assessed where the current energy sources in these oil fields are substituted by gas, diesel, co-generated geothermal power, or a combination of the three while maintaining the average power output in each field. The highest carbon footprint reduction is found in Scenario 1, which replaces 100% of the liquid fuel consumption with purchased gas (gas provided by a third party and treated outside the system’s limits), thereby achieving carbon footprint reductions up to 54% for OFB. This research opens the prospect for the use of renewable energies in the oil and gas industry.

Fibrous aragonite crusts occur in two consecutive Pleistocene successions in the Danakil Depression (Afar, Ethiopia). Lateral transitions between pristine and altered fibrous aragonite crusts document changes in texture associated with diagenesis. Crusts formed as essentially abiotic seafloor precipitates at the transition frommarine to evaporitic conditions. Diagenesis started with the dissolution of aragonite fans at the interface between single fans in non-laminated crusts and along lamination planes in isopachous, irregular, or crudely laminated crusts. Incomplete dissolution resulted in the development of secondary porosity within amatrix of undissolved aragonite fibers. Subsequently, the porosity was filled with calcite that systematically encased remaining aragonite crystals. This was followed by the dissolution of remnant aragonite fibers, producing a network of elongated inter- and intracrystalline pores that were eventually filled with low-Mg calcite. The stepwise substitution of fibrous aragonite by low-Mg calcite resulted in sparry, sparry-cloudy, sparry-micritic (including clotted micrite), and peloidal textures, which obscure the fibrous nature of the original deposits. Stable C- and O-isotope compositions suggest that early diagenesiswas driven by meteoric and evaporative fluids. These observations unequivocally demonstrate destructive diagenesis, resulting in secondary textures, which mimic micritic and grumous (peloidal and clotted) textures associated with sparry microfabrics. This suggests that these textures, classically interpreted as primarymicrobial precipitates and used as evidence of biogenicity in ancient microbialites, might be diagenetic products in some cases, even though at some stage, microbial processes and/or degradation of organic matter could have been involved in the diagenetic process., Swiss National Science Foundation (SNSF) 200021_163114, SNSF Ambizione 154810

The carnage wrought by systemic racism through social, judicial, and health injustices compels us to work towards a system that is fair and just for patients and colleagues. The evidence that change is necessary in medicine is hiding in plain sight in literature, oral histories, medical records, and news media. Notwithstanding this evidence, changing a system 400 years in the making will require a major paradigm shift. One of the many ways our department sought to catalyze such a shift was through media consumption, reflection, and discussion. Reading and studying literature and humanities in medicine can awaken our consciousness by making medicine an embodied practice that considers the totality of patients' lives in ways that a disembodied, purely scientific approach cannot. Thus, we started a Racial and Social Justice Book Club to normalize discussions about racial and social (in)justice and examine everything through an anti-racist lens. Herein, we describe our experiences in the inaugural year of the Book Club, a space to lend credence and dignity to the voices, experiences, and stories of folks who have long been marginalized by power structures in America, including medicine.