Performance and applications of lightweight geopolymer and alkali activated composites with incorporation of ceramic, polymeric and lignocellulosic wastes as aggregates: A review.

As the construction industry moves towards greater sustainability, the application of more durable and environmentally friendly materials, capable of providing comfort in buildings and infrastructure, is a key element to consider. In this context, the use of alkali-activated binders (AAB) and geopolymers (GP), which have a lower carbon footprint than ordinary Portland cement (OPC), has emerged as an important alternative. Moreover, the addition of waste-based lightweight aggregates (LWA) to AAB and GP matrices produces lightweight composites that offer enhanced mechanical performance and improved comfort as building materials, while offering an alternative use to the increasing number of waste materials from diverse sources. This paper presents a comprehensive review of the literature on the above-mentioned topics (waste LWA in an AAB/GP matrix) published between 2012 and 2023, mainly indexed in the Scopus database. The waste-based LWA reported in the literature were categorized, and their properties and morphology presented. Then, the influence of the size, quantity, and nature of the LWA on the composite's properties and performance was analyzed. Fresh state performance, mechanical performance, density, and thermal and acoustic insulation were considered. This review is complemented by a bibliometric analysis, where keyword correlation and co-authorship networks on this field are established. The review highlights the potential of cementitious composites including waste-based LWA as a sustainable building material for structural and non-structural applications. However, more studies are required to further understand the behaviour of these composites under innovative manufacturing processes, such as extrusion and 3D printing.

Evaluation of the pathologic response to neoadjuvant treatment in rectal cancer. Experience at the Instituto de Cancerología de Medellín (Colombia, 2011-2017). / Evaluación de la respuesta patológica al tratamiento neoadyuvante en cáncer de recto. Experiencia del Instituto de Cancerología de Medellín (Colombia, 2011-2017).

INTRODUCTION AND AIMS: Neoadjuvant therapy in rectal cancer is associated with a decrease in tumor size and is the therapeutic indication for patients with T3 or T4 tumors or lymph node involvement. Our aim was to describe the frequency of pathologic response and the survival rate in patients that underwent neoadjuvant therapy for rectal cancer. MATERIALS AND METHODS: A retrospective follow-up study with a survival analysis was conducted. Patients with locally advanced rectal cancer that received neoadjuvant treatment and were operated on at the Instituto de Cancerología Las Américas (Medellín, Colombia) were analyzed. Survival was calculated using the Kaplan-Meier method. RESULTS: A total of 152 patients were included. Mean patient age was 59 years (12.8 SD), 53.9% were men, and 58.6% of the patients were diagnosed with stage IIIB disease. The pathologic complete response (pCR) was achieved in 17% of the patients. A total of 146 (96.1%) patients received the chemoradiotherapy protocol. Fifty-two (34.2%) patients developed metastasis and/or relapse, and one (3.8%) of those patients had presented with pCR. The median follow-up period was 33 months (Q1-Q3: 20-45), with an overall survival rate of 79.5% (95% CI 70.9-85.8). The 5-year survival rate for the patients that had pCR was 80% (95% CI 20.3-96.9). CONCLUSIONS: The frequency of pCR was similar to that in other published studies and disease recurrence was lower, compared with patients with no response. The 5-year survival rate in patients with pCR was high, albeit lower than that reported in other studies.

Expresión de azúcares endometriales y del oviducto durante el ciclo reproductivo de la coneja / Expression of endometrial and oviductal glycoproteins during the reproductive cycle of female rabbit

Antecedentes: Numerosos factores han sido implicados en el proceso de implantación, entre ellos se destaca la presencia de glicoproteínas de superficie. Se ha demostrado en ratones, entre otros, que los tipos y cantidades de azúcares de superficie varían según el período del ciclo reproductivo en el que se encuentran, lo que podría sugerir un importante papel de estas variaciones en la mayor receptividad del útero al blastocisto. Objetivos: Describimos los carbohidratos de superficie del aparato reproductor de la coneja, correlacionándolos con los cambios en sus genitales externos, y con los distintos períodos de su ciclo reproductivo. Métodos: Se usaron 15 conejas, ovuladoras coitales, en las que se identifica el período del ciclo según cambios en sus genitales externos; 5 tenían vulva blanca (poca receptividad al macho y bajo índice de embarazos), 5 tenían vulva rosa, y 5 roja (máxima receptividad al macho y alto índice de embarazos). Se estudiaron variaciones en los azúcares de superficie en el oviducto, útero distal, útero medio y cuello uterino, representados por el grado de tinción de 5 lectinas: eritrina cristagalli (ECL), dolichos biforus agglutinin (DBA), ulex europaeus aglutinin-1(UEA-1), pisum sativum agglutinin (PSA) y artocarpus integrifolia (Jacalin). Resultados: Hubo predominio del disacárido N-acetilgalactosamina alfa 1-3N-acetilgalac-tosamina (DBA) en todos los períodos y lugares del aparato reproductor, exceptuando el período de vulva roja en útero medio, donde prevalece la beta galactosa (Jacalina). Los residuos de manosa/alfa glucosa (PSA), presentan alta reacción en los períodos de vulva rosa y roja en el oviducto y útero distal. La galactosa beta 1-4 N-acetil glucosamina (ECL) y la L-fucosa (UEA-1) tienen bajo nivel de expresión en todos los sitios y períodos. Conclusión: La ausencia del disacárido N-acetilgalactosamina alfa 1-3N-acetilgalac-tosamina en el período de vulva roja y en el útero medio y la prevalencia de la beta galactosa en...

Versión cefálica externa en la presentación podálica en embarazos mayores o iguales a 36 semanas, en el Hospital General de Medellín. 1990 – 1992 / Cephalic external version in podalic position in pregnancies of 36 weeks or longer terms. Medellín General Hospital 1990 -1992

Se realizó un estudio prospectivo, descriptivo, en el servicio de gineco-obstetricia en el Hospital General de Medellín, en pacientes con embarazo – 36 semanas y presentación podálica, a quienes se sometió a versión cefálica externa (V.C.E.) en el periodo comprendido entre Noviembre de 1990 a Noviembre de 1992. Se ejecutaron 45 versiones, de las cuales 18 (40 por ciento) fueron exitosas: 12 (26.67 por ciento) terminaran en parto vaginal en cefálica y 6 (13.33 por ciento) en parto por cesárea en cefálica. 27 (60 por ciento) versiones fueron no exitosas: 2 (4.44 por ciento) de ellas terminaron en parto vaginal en podálica y 25 (55.56 por ciento) en parto por cesárea en podálica...