Connecting Scientists Residing Abroad: A Review of Converciencia as a Practice to Engage the Guatemalan Scientific Diaspora From 2005-2020.

In 2005, the Guatemala National Secretariat of Science and Technology (Senacyt) introduced Converciencia, a program designed to connect Guatemalan scientists residing abroad with their country of origin. Converciencia has been a flagship practice for over 15 years. This program involves three main groups of participants: (i) science and technology (S&T) policy agents, (ii) the scientific community (including parts of the Guatemala scientific diaspora, GSD), and (iii) host institutions (local co-organizers, mainly universities, and research institutes). This article presents a comprehensive and balanced overview of the Converciencia program applying an in-depth analysis of its creation, evolution, leading trends, and legacies. Using a qualitative methodology and conducting a four-level analysis (descriptive, explanatory, normative, and prescriptive) allowed for the identification of nuances of this S&T practice in the context of a scientifically lagging country such as Guatemala. The detailed data collected through documentary and desk review, gray literature, focus group discussions, and semi-structured interviews resulted in a framework to highlight the strengths, weaknesses, opportunities, and threats (SWOTs) in the planning, organization, implementation, monitoring, and perception of the results achieved by Converciencia. Findings portray the contrasting views and perceptions from a single S&T practice, depending on the participating parties' roles and responsibilities. Direct participants examined how Converciencia has achieved its objectives while questioning the effectiveness and impact that the resources allocated to the initiative have yielded over time. Evidence indicates that despite the design, coordination, and evaluation limits of Converciencia, the GSD, the scientific community in Guatemala, and the host institutions are interested in the continuity of the practice. Indeed, the main recommendation involves restructuring and turning Converciencia into a robust S&T policy. Converciencia as a policy engaging the GSD could produce greater results and impacts by involving all the key actors in co-designing activities, clearly determining roles and responsibilities, and establishing performance and impact indicators for evaluation.

Engaging the Guatemala Scientific Diaspora: The Power of Networking and Shared Learning.

The underdevelopment of the higher education system in Guatemala and the fragility of its science and technology (S&T) contexts have compelled a significant number of talented Guatemalan scientists to be trained, educated, and employed abroad. The relocation of such skilled human power to different countries and regions has resulted in a growing Guatemalan Scientific Diaspora (GSD). Until recently, the emigration of scientists from the Global South to scientifically advanced countries in the North was studied as it negatively impacted the countries of origin. However, technological upgrades and globalization have progressively shifted the paradigm in which such scientific diasporas interact and connect, thus enabling them to influence their home countries positively. Due to the lack of knowledge-based evidence and functioning connecting platforms, the value and potential of the GSD in their involvement in proposing solutions to complex socio-economic, environmental, and other challenges faced by Guatemalan society remain unknown. Moreover, the lack of interaction of relevant stakeholders (S&T policy agents, international partners, higher education institutions and research centers, industry, and relevant not governmental organizations) represents a pervasive obstacle to the untapped impact of the GSD in the country. This study outlines the Guatemalan scientific diasporas' networking as a mechanism for building research excellence and intellectual capital. This force could respond to the need to strengthen the national science capacities and meet the demands for knowledge production and access to broader sectors of society. This research applied qualitative methodology that, through the conduction of focus group discussions and semi-structured interviews with members of the Guatemalan scientific community and relevant key stakeholders, delved into the existence and articulation of the GSD and potential stages for their engagement with their country of origin. Findings highlight the importance of digital and technological pathways that might leverage the GSD's knowledge and experience, channeling skills, and international connections for better interaction with the Guatemalan society. Furthermore, the discussion addresses how technology might turn brain drain into brain circulation, enabling the articulation of the GSD as a viable opportunity to generate collaboration between scientists abroad and local actors, ultimately impacting the building and development of Guatemalan science and national research capacities.

Photocatalytic activity, water absorption capacity, and thermal stability of white cement-based mortars with polysiloxane silicone and different doses of titanium dioxide nanoparticles / Actividad fotocatalítica, absorción de agua y estabilidad térmica de morteros a base de cemento blanco con silicona de polisiloxano y diferentes dosis de nanopartículas de dióxido de titanio

White cement-based mortars in urban areas are usually discolored and altered their esthetic properties due to air pollutants. The addition of nanoparticles in these mortars can provide photocatalytic properties that can decompose pollution agents. Likewise, other hydrophobic agents have been individually studied to improve outdoor building constructions. Therefore, this study presented the photocatalytic and hydrophobic effect of adding nano-TiO2and silicone hydrophobic powder (DOWSILTM) in a white cement matrix. The nano-TiO2 were characterized by X-Ray Diffraction (XRD); afterwards, the mortar was mixed with additions of nano-TiO2 (0.0, 0.5, 1.0, 3.0%) and DOWSILTM (0.0, 0.5%). The mortar's photocatalytic performance was evaluated using a modification of the standard Italian test Ente Nazionale Italiano di Unificazione 11259:2016 based on Rhodamine B (RhB) degradation on the sample exposed to UV irradiation. Therefore, mortar samples were subjected to UV irradiation to degrade the organic dye rhodamine B, monitoring their color variation using a C I E L* a* b* spectrophotometer. Moreover, the water permeability and the contact angle were evaluated. This research demonstrates that the white cement-based mortar samples added with nano-TiO2/DOWSILTM possess photocatalytic activity. The samples with the addition of 1.0%/0.5% and 3.0%/0.5% nano-TiO2/DOWSILTM showed a higher RhB degradation for R4 and R26. Therefore, these two materials can be employed in these proportions to improve the quality of the white cement-based mortars in urban constructions.

Los morteros a base de cemento blanco generalmente se decoloran y alteran sus propiedades estéticas debido a los contaminantes del aire en las áreas urbanas. Nanopartículas añadidas a estos morteros pueden proporcionar propiedades fotocatalíticas que descomponen estos contaminantes. Asimismo, otros agentes hidrofóbicos se han estu-diado individualmente para mejorar las construcciones a la intemperie. Por lo tanto, se presenta el efecto fotocatalítico e hidrofóbico al incorporar nano-TiO2 y silicona hidrofóbica de polisiloxano (DOWSILTM) en una matriz de cemento blanco. El nano-TiO2 se caracterizó por medio de Difracción de Rayos X (DRX); luego, el mortero se mezcló con adiciones de nano-TiO2 (0.0, 0.5, 1.0, 3.0%) y DOWSILTM (0.0, 0.5%). Los morteros se sometieron a irradiación UV, para degradar el colorante orgánico rodamina B, monitoreando su variación de color usando un espectrofotómetro C I E L* a* b*. La eficiencia fotocatalítica del mortero se evaluó utilizando una modificación de la norma italiana Ente Nazionale Italiano di Unificazione 11259:2016 basada en la degradación de la rodamina B (RhB) en el mortero expuesto a la radiación UV. Además, se evaluó la permeabilidad al agua y el ángulo de contacto. Esta investigación demostró que el mortero de cemento con nano-TiO2/ DOWSILTM posee actividad fotocatalítica. Las muestras con 1.0%/0.5% y 3.0%/0.5% nano-TiO2/DOWSILTM mostraron una mayor eficiencia de degradación de RhB para R4 y R26. Por lo tanto, estos materiales tienen potencial para mejorar la calidad de los morteros en construcciones urbanas.

Efficiency improvement using bis(trifluoromethane) sulfonamide lithium salt as a chemical additive in porphyrin based organic solar cells.

Two new conjugated acceptor-π-donor-π-acceptor (A-π-D-π-A) porphyrins have been synthesised using 3-ethylrhodanine (1a) or dicyanovinylene (1b) groups as acceptor units. Their optical and electrochemical properties made these materials excellent electron donors along with PC71BM as the acceptor for solution-processed bulk heterojunction organic solar cells. The devices based on 1a:PC71BM (1 : 2) and 1b:PC71BM (1 : 2) processed with CB showed low power conversion efficiencies (PCE) of 2.30% and 2.80%, respectively. Nonetheless, after processing the active layer using a mixture of 3 vol% of a pyridine additive in THF, the PCE was enhanced up to 5.14% and 6.06% for 1a:PC71BM and 1b:PC71BM, respectively. Moreover, when we used LiTFSI as the chemical additive in pyridine/CB-processed 1b:PC71BM an excellent PCE of 7.63% was recorded. The effects over the film morphology and the device characteristics (Jsc, Voc and FF) due to the introduction of LiTFSI are discussed.