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Additive manufacturing (AM), also known as 3D printing, has revolutionized the production of complex geometric structures across various industries. This study presents an innovative approach by integrating zinc carbonate basic (ZCB) precursor with polylactic acid (PLA) to develop composite filaments for fused deposition modeling (FDM) 3D printers. The resulting filaments undergo surface transformation into zinc oxide (ZnO) through high-power laser irradiation. Thermal analysis (TGA-DSC) and Fourier-transform infrared spectroscopy (FTIR) were used to confirm the decomposition of ZCB ([ZnCO₃]₂·[Zn(OH)₂]₃) into ZnO during the thermal decomposition stages. The study successfully extruded a composite filament containing 10% of ZCB, which worked adequately in 3D printing. The printed parts were analyzed through tensile tests (based on ASTM D638-5 standard), showing a notable difference in mechanical behavior between the commercial filament PLA and the composite filament (PLAC10). Laser irradiation of these samples facilitated a targeted conversion to ZnO, verified through scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The integration of zinc oxide within the printed structures enhances structural stability and provides surfaces enriched with ZnO, a metal oxide with widely reported applications. Furthermore, an irradiated 3D-printed sample demonstrated chemo-resistive properties upon carbon monoxide (CO) exposure, underlining its potential as a gas sensor and confirming its semiconductor nature. This approach provides a cost-effective and efficient way to develop innovative devices with integrated functional materials.

Introductions: Three patients presented with a colo-cutaneous fistula from the neo-rectum to previous laparoscopic port sites, following an otherwise technically correct pull-through for Hirschsprung disease. We evaluated each case to provide guidance to pediatric surgeons on how to avoid this previously unreported complication. Case presentation: All three patients were male and had a laparoscopic-assisted pull-through for Hirschsprung disease as neonates. All patients underwent intra-operative colonic biopsies above the transition zone, that were closed using an Endoloop ligature (Ethicon), which later proved to be the source of the fistula. The fistulas manifested at variable times: ten days, six months, and five years after the index pull-through. Clinical findings were skin changes, abscess or drainage at previous laparoscopic port sites. Contrast studies were performed to diagnose the underlying pathology. Two patients had primary fistula closure with a diverting ileostomy, followed by ileostomy closure. One patient with delayed symptom presentation had a temporary ileostomy, redo pull-through, and ultimately an ileostomy closure. All three patients recovered without long term sequelae. Conclusion: The technical error in all of these cases was the utilization of an endoloop ligature for the biopsy site. Furthermore, when the biopsy is taken above a transition zone, it can be postulated that the increased physiologic back-pressure from the sphincter could lead to fistula development and propagation. As more cases are performed with minimally invasive techniques, we must be adamant about evaluating for new, previously un-encountered complications such as this one. An adequate closure of the full-thickness biopsy site could prevent this complication.

Background: Postoperative anal dilations (PAD) are the standard of care for patients after a posterior sagittal anorectoplasty (PSARP) for anorectal malformation (ARM) or a transanal pull-through (TP) procedure for Hirschsprung disease (HD). This study assessed the psychosocial impact of PAD among caregivers of children with ARM or HD, which may inform postoperative care strategies. Methods: Caregivers of patients with ARM and HD who underwent PSARP or TP within five years participated in the online survey. Questions included demographics, patient and caregiver experiences with PAD, and baseline psychosocial functioning. Quantitative results were reported descriptively, while qualitative responses were summarized as major themes. Results: The survey indicated a response rate of 26% caregivers, with most being female (91%) and biological mothers (85%). Patients were mostly male (65%), born with ARM (74%), and were five months old on average when PAD began. Caregivers reported that during PAD, children experienced distress (56%), pain (44%), and fear (41%), while a third noted no negative reactions. Over time, their child’s ability to cope with PAD got easier (38%) or stayed the same (41%). Caregivers reported worry/anxiety (88%), guilt (71%), stress (62%), and frustration (35%), noting that additional coping strategies to manage the emotional and logistical challenges of daily PAD would be helpful. Conclusion: Although PAD is necessary, it can be highly stressful for the patients and their caregivers. Key findings emphasized the need for additional coping strategies and highlighted the importance of integrating psychosocial support into the postoperative care regimen.

Because of the SARS-CoV-2 pandemic, telemedicine has been implemented as an alternative channel for face-to-face medical care. It is essential to evaluate patient satisfaction regarding the use of telemedicine to assess its feasibility as a new care modality in the future. Objective: To evaluate the user satisfaction of the parents or caregivers of pediatric patients with colorectal pathology regarding the use of telemedicine. Material and method: Cross-sectional study using a survey with a Likert scale. The parents of patients with Hirschsprung disease, anorectal malformations, and severe constipation in a bowel management program were given the Telehealth Usability Questionnaire (TUQ) validated Spanish version through Google Forms. Results: 24 surveys were collected. 75 % consider that Telemedicine improves access to health care services and saves time traveling. 83 % report that they could express themselves adequately and felt comfortable using this means of communication. 57 % believe Telemedicine is an acceptable way to receive health care instructions. 75 % are satisfied with the system and would use it again. Conclusion: Telemedicine care is a valuable tool to complement the care of pediatric patients with colorectal pathology, which is probably here to stay. Strategies should be implemented since it has great potential to complement face-to-face care, exceptionally patient follow-up, in parental satisfaction. Level of evidence: III.

Background: In Patients with Hirschsprung Disease (HSCR) suffering from obstructive symptoms after their pull-through surgery, a transition zone pull-through (TZPT) was suggested as a causing factor. Current guidelines recommend a reoperation resecting the transition zone in these patients. This present study reports the clinical outcomes in patients with a confirmed TZPT. Methods: A retrospective review of patients who underwent a primary transanal pull-through for recto-sigmoid HSCR at the Children's Hospital Colorado from January 2010 until June 2020 was performed. We included patients with a TZPT confirmed on the definitive histopathological report of the proximal margin's circumference obtained at the time of their pull-through surgery and follow-up at the Children's Hospital Colorado. Demographic data were collected. The primary outcome of interest was fecal control, episodes of Hirschsprung-associated enterocolitis (HAEC), the necessity of bowel management (with either laxatives or enemas), and a redo pull-through. Results: Six patients had a TZPT. Two patients suffered episodes of HAEC. One patient is fecal incontinent. None of them underwent redo pull-through surgery. Medical treatment was successful in all with obstructive symptoms. Conclusion: Patients who underwent a pull-through surgery for HSCR with retained transition zone may suffer from obstructive symptoms, which can be managed conservatively with medical treatment. A TZPT is not necessarily associated with persistent obstructive symptoms. Level of evidence/type of study: Level III, retrospective.

Expression quantitative trait loci (eQTL) data have proven important for linking non-coding loci to protein-coding genes. But eQTL studies rarely measure microRNAs (miRNAs), small non-coding RNAs known to play a role in human brain development and neurogenesis. Here, we performed small-RNA sequencing across 212 mid-gestation human neocortical tissue samples, measured 907 expressed miRNAs, discovering 111 of which were novel, and identified 85 local-miRNA-eQTLs. Colocalization of miRNA-eQTLs with GWAS summary statistics yielded one robust colocalization of miR-4707–3p expression with educational attainment and brain size phenotypes, where the miRNA expression increasing allele was associated with decreased brain size. Exogenous expression of miR-4707–3p in primary human neural progenitor cells decreased expression of predicted targets and increased cell proliferation, indicating miR-4707–3p modulates progenitor gene regulation and cell fate decisions. Integrating miRNA-eQTLs with existing GWAS yielded evidence of a miRNA that may influence human brain size and function via modulation of neocortical brain development.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

How neurodevelopmental disorder-associated risk genes are translated into spatially patterned brain vulnerabilities is unclear. Here, the authors show that disorder-specific patterns of neuroanatomical changes are aligned to brain expression maps of disease risk genes in healthy subjects.

The advance in control engineering education needs well-designed studies that validate what methods and tools work best. This paper addresses the lack of empirical evidence supporting innovations in control engineering education by proposing a methodology that works at different abstraction levels. Hence, innovations' impact on students' performance can be statistically analyzed either globally or locally by examining competencies or fine-grained indicators, respectively. The article reports the application of the methodology for evaluating an interactive simulation tool, named LCSD, on 101 students at the Pontifical Catholic University of Valparaiso in Chile. According to the experimental results, LCSD is an effective free alternative to enhance the student's skills on control system analysis for our automatic control course. Also, some improvements have been identified for future LCSD versions.

Competency-based education is becoming increasingly adopted by higher education institutions all over the world. This paper presents a framework that assists instructors in this pedagogical paradigm and its corresponding open-source implementation. The framework supports the formal definition of competency assessment models and the students' evaluation under these models. It also provides distinct learning analytics for identifying course shortcomings and validating corrective actions instructors have introduced in a course. Finally, this paper reports the benefits of applying our framework to an engineering course at the Pontifical Catholic University, Valparaíso, Chile for three years.

The ethanol (active) and methanol (toxic) substances content were quantified for commercial sanitizing gels. The health emergency caused by the COVID-19 epidemic has motivated to production of sanitizing gels to cover higher demand. The analytical composition of 24 commercial gels is reported (15 produced by national and transnational companies, and 9 collected gels which were in use at public areas). From the results it was found, that only one brand of 15 gels meets the quality requirements regarding 70% (wt./wt.) of ethanol content. Concerning to the collected gels, none of them contains the minimum active compound required. The non-compliance of this requirement means that these gels present its sanitizing action diminished. A striking result is that 25% of commercially packaged gels contain methanol - a toxic substance - in alarming amounts, hundreds of times more than the FDA upper limits requirement. DOI: https://doi.org/10.54167/tecnociencia.v15i1.761

The open-source hardware movement is becoming increasingly popular due to the emergence of successful low-cost technologies, such as Arduino and Raspberry Pi, and thanks to the community of makers that actively share their creations to be freely studied, modified, and re-distributed. Numerous authors have proposed distinct ways to seize this approach for accomplishing a variety of learning goals: enabling scholars to explore scientific concepts, promoting students’ creativity, helping them to be more fluent and expressive with new technologies, and so on. This paper reports a systematic mapping study that overviews the literature on open-source hardware in education by analyzing and classifying 676 publications. The results of our work provide: 1) guidance on the published material (identifying the most relevant papers, publication sources, institutions, and countries); 2) information about the pedagogical uses of open-source hardware (showing its main educational goals, stages, and topics where it is principally applied); and 3) directions for future research.

Summary: The human cerebral cortex possesses distinct structural and functional features that are not found in the lower species traditionally used to model brain development and disease. Accordingly, considerable attention has been placed on the development of methods to direct pluripotent stem cells to form human brain-like structures termed organoids. However, many organoid differentiation protocols are inefficient and display marked variability in their ability to recapitulate the three-dimensional architecture and course of neurogenesis in the developing human brain. Here, we describe optimized organoid culture methods that efficiently and reliably produce cortical and basal ganglia structures similar to those in the human fetal brain in vivo. Neurons within the organoids are functional and exhibit network-like activities. We further demonstrate the utility of this organoid system for modeling the teratogenic effects of Zika virus on the developing brain and identifying more susceptibility receptors and therapeutic compounds that can mitigate its destructive actions. : Cerebral organoids recapitulate many aspects of human corticogenesis and are a useful platform for modeling neurodevelopmental mechanisms and diseases. Watanabe et al. describe enhanced organoid methods and model ZIKV pathology. More susceptibility receptors for ZIKV are identified, and differential effects of various compounds to mitigate ZIKV-induced cytopathy are demonstrated. Keywords: neurogenesis, neural stem cell, embryonic stem cell, organoid, differentiation, neural development, cerebral cortex, Zika virus, human brain

Contribution: A competency assessment framework that enables learning analytics for course monitoring and continuous improvement. Our work fills the gap in systematic methods for competency assessment in higher education. Background: Many institutions are shifting toward competency-based education (CBE), thus encouraging their educators to start evaluating their students under this paradigm. Previous research shows that structured assessment models are fundamental in guiding educators toward this adoption. Intended Outcomes: An assessment model for CBE that is easy to adopt and use, while facilitating the application of learning analytics techniques. Application Design: The new framework considerably extends a prior model we proposed three years ago. Two engineering competency-based courses used the framework for assessment. Assessment rubrics were prepared and used for evaluating and collecting the students' data progressively, thus enabling the use of learning analytics for decision-making. Findings: Thanks to the model: 1) students received a detailed report of their achievements, including a thorough explanation and justification of the evaluation criteria and 2) instructors could improve the course and provide objective evidence of their actions to quality assurance agencies. As a result, the framework is presently being used in 15 courses taught at eight different university degrees at the Pontifical Catholic University of Valparaiso (PUCV).

This paper presents an open course in the University Network of Interactive Laboratories, which offers several virtual and remote laboratories on automatic control, accessible to anyone. All the details on one of these labs (a two electric coupled drives system that allows performing control practices in a 2 × 2 MIMO system with industrial applications) and the activities that can be performed with it are given. We use a low-cost solution for developing the virtual and remote labs shared in this open course, based on the use of a free authoring tool Easy Java/Javascript Simulations (EJsS) for building the laboratories' user interfaces and a cheap development platform board (BeagleBone Black). The virtual and remote labs are deployed into a free Learning Management System (Moodle) Web environment that facilitates their management and maintenance.

Constipation is a common disease and one of the most frequent reasons of visits in pediatric clinics, complications related to constipation denote an inadequate diagnosis and/or treatment. This article is addressed for physicians who provide care to children with functional constipation and, it proposes in a practical manner how to diagnose this problem, emphasizing the essential information that should be obtained from the clinical history and from the workup helpful for its diagnosis. The “bowel management program” is the proposed treatment; this pro- gram has a rate success higher than 90%, even, in patients with severe chronic constipation with frequent relapses and multiple treatments.

El estreñimiento es un problema común y es una de las principales causas de consulta en la edad pediátrica, sus complicaciones indican un problema en el diagnóstico, en el tratamiento, o en ambos. Este tra- bajo está dirigido a los médicos que atienden niños con estreñimiento funcional e intenta explicar, de una manera práctica, cómo diagnosticar este problema destacando la información imprescindible que se debe obtener de la historia clínica y los estudios auxiliares de diagnóstico que pueden ser de utilidad para descartar organicidad. El “programa de rehabilitación intestinal” es la forma de tratamiento que se propone; éste tiene un éxito mayor a 90%, incluso en pacientes con estreñimiento crónico-grave en el que las recaídas y los fracasos son frecuentes.

Introduction: in Mexico, approximately 1 000 children each year are born with anorectal malformation (ARM). Despite surgical correction, those children present fecal function problems (60-70% have difficult to manage constipation). A Bowel Management Program (BMP) was implemented, which consists of initial rectal disimpaction, followed by administration of a stimulant laxative (sennosides), with favorable results. The objective of this study was to describe the effectiveness of the BMP in children with constipation secondary to ARM. Material and methods: A descriptive, retrospective, transverse study to answer the question: how effective is the BMP in children with constipation secondary to ARM? Efficacy was evaluated by means of a construct with three variables (daily fecal evacuations, absence of fecal staining, and simple abdominal x-ray without fecal residue in rectum and left colon after evacuation). All children with surgically corrected ARM and constipation from two national referral centers for children with the condition were included. Results: of 151 children with ARM monitored in outpatient service, only 67.33% had constipation. Of this group, 88.1% showed good response to the BMP. The average dose of sennoside was 8.45 mg/kg, 95% CI: 5.94-11.12 mg/kg (199.5 mg total dose; 95% CI: 139.50-259.50 mg). Abdominal cramp was the primary adverse effect reported (5.8%). Discussion: use of sennosides had a positive impact on our patients’ quality of life by achieving colonic and rectal emptying and preventing daily fecal staining.

Intellectual disability (ID) is a prevalent developmental disorder of cognition that remains incurable. Here, we report that knockdown of the X-linked ID (XLID) protein polyglutamine-binding protein 1 (PQBP1) in neurons profoundly impairs the morphogenesis of the primary cilium, including in the mouse cerebral cortex in vivo. PQBP1 is localized at the base of the neuronal cilium, and targeting its WW effector domain to the cilium stimulates ciliary morphogenesis. We also find that PQBP1 interacts with Dynamin 2 and thereby inhibits its GTPase activity. Accordingly, Dynamin 2 knockdown in neurons stimulates ciliogenesis and suppresses the PQBP1 knockdown-induced ciliary phenotype. Strikingly, a mutation of the PQBP1 WW domain that causes XLID disrupts its ability to interact with and inhibit Dynamin 2 and to induce neuronal ciliogenesis. These findings define PQBP1 and Dynamin 2 as components of a signaling pathway that orchestrates neuronal ciliary morphogenesis in the brain.

A través de este trabajo se desarrolla una nueva herramienta de sostenibilidad ambiental (Índice de Impacto Energético, IIE) para la clasificación de los diversos proyectos en minas de hierro, analizando dos parámetros principales: el consumo de energía y las consecuentes emisiones de CO2. El IIE tiene en cuenta diferentes propiedades del mineral (calidad, tamaño, dureza, ley, reducibilidad, ratio mineral/estéril y tipo de yacimiento), el proceso minero (método de explotación, mineralurgia o tecnología aplicada) y el transporte (considerando distancias recorridas).

Air levitation is the process by which an object is lifted without mechanical support in a stable position, by providing an upward force that counteracts the gravitational force exerted on the object. This work presents a low-cost lab implementation of an air levitation system, based on open solutions. The rapid dynamics makes it especially suitable for a control remote lab. Due to the system’s nature, the design can be optimized and, with some precision trade-off, kept affordable both in cost and construction effort. It was designed to be easily adopted to be used as both a remote lab and as a hands-on lab.

Autism spectrum disorder (ASD) involves substantial genetic contributions. These contributions are profoundly heterogeneous but may converge on common pathways that are not yet well understood. Here, through post-mortem genome-wide transcriptome analysis of the largest cohort of samples analysed so far, to our knowledge, we interrogate the noncoding transcriptome, alternative splicing, and upstream molecular regulators to broaden our understanding of molecular convergence in ASD. Our analysis reveals ASD-associated dysregulation of primate-specific long noncoding RNAs (lncRNAs), downregulation of the alternative splicing of activity-dependent neuron-specific exons, and attenuation of normal differences in gene expression between the frontal and temporal lobes. Our data suggest that SOX5, a transcription factor involved in neuron fate specification, contributes to this reduction in regional differences. We further demonstrate that a genetically defined subtype of ASD, chromosome 15q11.2-13.1 duplication syndrome (dup15q), shares the core transcriptomic signature observed in idiopathic ASD. Co-expression network analysis reveals that individuals with ASD show age-related changes in the trajectory of microglial and synaptic function over the first two decades, and suggests that genetic risk for ASD may influence changes in regional cortical gene expression. Our findings illustrate how diverse genetic perturbations can lead to phenotypic convergence at multiple biological levels in a complex neuropsychiatric disorder.