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The COVID pandemic forced teachers to be imaginative, especially with purely practical subjects such as laboratory chemistry. In the Universidad Nacional Autónoma de México, the first-semester chemistry laboratory of the Biology course was taught with a chemistry set to be used at home. The use of the kit was evaluated from the perspective of knowledge acquired, motivation, and attitude. For comparison, groups that did not have the kit were also evaluated. The results for the fall semester 2020, showed that students who were supplied with a home kit remained motivated and had greater confidence in their skills to cope in the chemistry laboratory than did those without it. Family involvement in setting up the materials for the experiments had a beneficial effect on the family dynamic while they were enduring lockdown. The home kit experience was again assessed in the fall semester of 2021 with a new cohort of students; these students were markedly less motivated that those of the previous year’s intake, and their attitudes were less positive. Socioeconomic background showed differences for the first cohort on their learning scores unlike the second cohort, probably attributable to depression, boredom, fear, or uncertainty. The teachers found that their interaction with the students during the experiments with the chemistry kit reinforced theoretical concepts. The experience gained with the chemistry set during the pandemic, together with feedback from the surveys applied to the teachers, gave us the necessary confidence to propose this approach to conduct on formal virtual classes.

Abstract: Endometrial cancer represents the most frequent neoplasia from the corpus uteri and comprisesthe 14th leading cause of death in women worldwide. Risk factors that contribute to the diseaseinclude early menarche, late menopause, nulliparity, and menopausal hormone use, as well as hypertensionand obesity comorbidities. The clinical effectiveness of chemotherapy is variable, suggestingthat novel molecular targeted therapies against specific cellular processes associated with the maintenanceof cancer cell survival and therapy resistance ameliorate the rates of success in endometrialcancer treatment. In the course of tumor growth, cancer cells must adapt to decreased oxygen availabilityin the microenvironment by upregulation of hypoxia-inducible factors, which orchestrate theactivation of a transcriptional program leading to cell survival. During this adaptative process, thehypoxic cancer cells may acquire invasive and metastatic properties as well as increased cell proliferationand resistance to chemotherapy, enhanced angiogenesis, vasculogenic mimicry, and maintenanceof cancer cell stemness, which contribute to more aggressive cancer phenotypes. Several studieshave shown that hypoxia-inducible factor 1 alpha (HIF-1α) protein is aberrantly overexpressed inmany solid tumors of the breast, prostate, ovarian, bladder, colon, brain, and pancreas. Thus, it hasbeen considered an important therapeutic target. Here, we reviewed the current knowledge of therelevant roles of cellular hypoxia mechanisms and HIF-1α functions in diverse processes associatedwith endometrial cancer progression. In addition, we also summarize the role of microRNAs in theposttranscriptional regulation of protein-encoding genes involved in the hypoxia response in endometrialcancer. Finally, we pointed out the need for urgent targeted therapies to impair the cellularprocesses activated by hypoxia in the tumor microenvironment.

This study presents the optical improvement of a high flux solar simulator (HFSS) with controllable flux-spot capabilities developed for researching solar thermal and thermochemical processes. The HFSS is comprised of seven 2.5  kW_el Xenon arc lamps coupled with ellipsoidal reflectors, a servo-controlled attenuator curtain, and three-axes linear test bench. Different attenuators were designed and tested in order to identify the best curtain geometry to improve the HFSS modulation with the lowest possible radiative losses. The optical design improvement was performed with the aid of TracePro, a Monte Carlo ray-tracing software. From simulation results, radiative peak flux from 1700 to 480  kWm^−2 from the focal plane to 300 mm further back was estimated without curtains. By using the attenuators, flux levels from 1570 to 92  kWm^−2 at the focal plane were also estimated. An experimental validation was achieved with a single lamp-reflector unit obtaining peak flux distributions from 200±20  kWm^−2 to 97±9.7  kWm^−2 from the focal plane to 300 mm behind. Flux modulation from 170 to 1.5  kWm^−2 was also measured at the focal plane using a servo-controlled curtain from fully-open slats (0°) to partially closed (60°). With this attenuator, introduced as the shutter of the system, the use of several lamps or electronic rectifiers is avoided and the radiative flux is modulated with high resolution in an optomechatronical form.

•A multi-lamp low flux solar simulator design is optimized by ray tracing analysis.•An average flux of 1198 W/m2can be achieved with an efficiency of 25.7%•The flux non-uniformity can be kept ≤2% over a target area of 2000 x 1000 mm.•The radiative flux level can be adjusted between 1162 to 105 W/m2.•A Class A modular solar simulator is achieved for large target areas.

Factors affecting immunogenicity of the first 2 doses of oral poliovirus vaccine (OPV) among unimmunized Mayan infants were prospectively evaluated. The relative impact of multiple variables, including mass or routine vaccination, concurrent enteric bacterial (salmonella, shigella, and campylobacter) and viral (adenovirus 40/41, astrovirus, nonpolio enteroviruses, and rotavirus) infections, interference among Sabin vaccine viruses, and preexisting poliovirus antibodies were studied. Sera were available from 181 infants after 2 OPV doses. Seroresponses were 86% to Sabin type 1, 97% to Sabin type 2, and 61% to Sabin type 3 vaccines. Mass versus routine vaccination and preexisting poliovirus antibodies did not affect immunogenicity. By multiple logistic regression analysis, fecal shedding of homologous Sabin strains was associated with increased seroresponses to all Sabin types, especially to Sabin type 3. Decreased OPV immunogenicity was primarily attributable to interference of Sabin type 3 by Sabin type 2. OPV formulations with higher doses of Sabin type 3 could improve immunogenicity among infants in developing countries.