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Abstract This year-long research analyzed emerging risks in influent, effluent wastewaters and biosolids from six wastewater treatment plants in Spain’s Valencian Region. Specifically, it focused on human enteric and respiratory viruses, bacterial and viral faecal contamination indicators, extended-spectrum beta-lactamases-producing Escherichia coli, and antibiotic-resistance genes. Additionally, particles and microplastics in biosolid and wastewater samples were assessed. Human enteric viruses were prevalent in influent wastewater, with limited post-treatment reduction. Wastewater treatment effectively eliminated respiratory viruses, except for low levels of SARS-CoV-2 in effluent and biosolid samples, suggesting minimal public health risk. Antibiotic resistance genes and microplastics were persistently found in effluent and biosolids, thus indicating treatment inefficiencies and potential environmental dissemination. This multifaced research sheds light on diverse contaminants present after water reclamation, emphasizing the interconnectedness of human, animal, and environmental health in wastewater management. It underscores the need for a One Health approach to address the United Nations Sustainable Development Goals.

Abstract Classical epidemiology relies on incidence, mortality rates, and clinical data from individual testing, which can be challenging for many countries. Therefore, innovative, flexible, cost‐effective, and scalable surveillance techniques are needed. Wastewater‐based epidemiology (WBE) has emerged as a highly powerful tool in this regard. WBE analyses substances excreted in human fluids and faeces that enter the sewer system. This approach provides insights into community health status and lifestyle habits. WBE serves as an early warning system for viral surveillance, detecting the emergence of new pathogens, changes in incidence rates, identifying future trends, studying outbreaks, and informing the performance of action plans. While WBE has long been used to study different viruses such as poliovirus and norovirus, its implementation has surged due to the pandemic caused by the Severe Acute Respiratory Syndrome Coronavirus 2. This has led to the establishment of wastewater surveillance programmes at international, national, and community levels, many of which remain operational. Furthermore, WBE is increasingly applied to study other pathogens, including antibiotic resistance bacteria, parasites, fungi, and emerging viruses, with new methodologies being developed. Consequently, the primary focus now is on creating international frameworks to enhance states' preparedness against future health risks. However, there remains considerable work to be done, particularly in integrating the principles of One Health into epidemiological surveillance to acknowledge the interconnectedness of humans, animals, and the environment in pathogen transmission. Thus, a broader approach to analysing the three pillars of One Health must be developed, transitioning from WBE to wastewater and environmental surveillance, and establishing this approach as a routine practice in public health.

Climate change, unpredictable weather patterns, and droughts are depleting water resources in some parts of the globe, where recycling and reusing wastewater is a strategy for different purposes. To counteract this, the EU regulation for water reuse sets minimum requirements for the use of reclaimed water for agricultural irrigation, including a reduction in human enteric viruses. In the present study, the occurrence of several human enteric viruses, including the human norovirus genogroup I (HuNoV GI), HuNoV GII, and rotavirus (RV), along with viral fecal contamination indicator crAssphage was monitored by using (RT)-qPCR methods on influent wastewater and reclaimed water samples. Moreover, the level of somatic coliphages was also determined as a culturable viral indicator. To assess the potential viral infectivity, an optimization of a capsid integrity PMAxx-RT-qPCR method was performed on sewage samples. Somatic coliphages were present in 60% of the reclaimed water samples, indicating inefficient virus inactivation. Following PMAxx-RT-qPCR optimization, 66% of the samples tested positive for at least one of the analyzed enteric viruses, with concentrations ranging from 2.79 to 7.30 Log10 genome copies (gc)/L. Overall, most of the analyzed reclaimed water samples did not comply with current EU legislation and contained potential infectious viral particles.

Cold plasma is a promising alternative for water treatment owing to pathogen control and a plethora of issues in the agriculture and food sectors. Shellfish pose a serious risk to public health and are linked to large viral and bacterial outbreaks. Hence, current European regulations mandate a depuration step for shellfish on the basis of their geographical growth area. This study investigated the inactivation of relevant viral and bacterial pathogens of three plasma-activated seawaters (PASWs), and their reactive oxygen and nitrogen species (RONS) composition, as being primarily responsible for microbial inactivation. Specifically, F-specific (MS2) and somatic (φ174) bacteriophage, cultivable surrogate (murine norovirus, MNV, and Tulane virus, TV), and human norovirus (HuNoV GII.4) inactivation was determined using plaque counts and infectivity assays, including the novel human intestinal enteroid (HIE) model for HuNoV. Moreover, the kinetic decay of Escherichia coli, Salmonella spp., and Vibrio parahaemolyticus was characterized. The results showed the complete inactivation of phages (6–8 log), surrogates (5–6 log), HuNoV (6 log), and bacterial (6–7 log) pathogens within 24 h while preventing cytotoxicity effects and preserving mussel viability. Nitrites (NO2−) were found to be mostly correlated with microbial decay. This research shows that PASWs are a suitable option to depurate bivalve mollusks and control the biohazard risk linked to their microbiological contamination, either viral or bacterial.

Abstract Combined kinetic analysis of plasma SARS-CoV-2 RNAemia, Nucleocapsid (N)-antigenemia and virus-specific antibodies may help ascertain the role of antibodies in preventing virus dissemination in COVID-19 patients. We performed this analysis in a cohort of 71 consecutive critically ill COVID-19 patients (49 male; median age, 65 years) using RT-PCR assay, lateral flow immunochromatography method and receptor binding domain (RBD) and N-based immunoassays. A total of 338 plasma specimens collected at a median of 12 days after symptoms onset were available for analyses. SARS-CoV-2 RNAemia and N-antigenemia were detected in 37 and 43 specimens from 26 (36.5%) and 30 (42.2%) patients, respectively. Free RNA was the main biological form of SARS-CoV-2 found in plasma. The detection rate for both viral components was associated with viral load at the upper respiratory tract. Median time to SARS-CoV-2-RBD antibody detection was 14 days (range, 4–38) from onset of symptoms. Decreasing antibody levels were observed in parallel to increasing levels of both RNAemia and N-antigenemia, yet overall a fairly modest inverse correlation (Rho = −0.35; P

The 2023 International Virus Bioinformatics Meeting was held in Valencia, Spain, from 24–26 May 2023, attracting approximately 180 participants worldwide. The primary objective of the conference was to establish a dynamic scientific environment conducive to discussion, collaboration, and the generation of novel research ideas. As the first in-person event following the SARS-CoV-2 pandemic, the meeting facilitated highly interactive exchanges among attendees. It served as a pivotal gathering for gaining insights into the current status of virus bioinformatics research and engaging with leading researchers and emerging scientists. The event comprised eight invited talks, 19 contributed talks, and 74 poster presentations across eleven sessions spanning three days. Topics covered included machine learning, bacteriophages, virus discovery, virus classification, virus visualization, viral infection, viromics, molecular epidemiology, phylodynamic analysis, RNA viruses, viral sequence analysis, viral surveillance, and metagenomics. This report provides rewritten abstracts of the presentations, a summary of the key research findings, and highlights shared during the meeting.

Abstract Isolation, contact tracing and restrictions on social movement are being globally implemented to prevent and control onward spread of SARS-CoV-2, even though the infection risk modelled on RNA detection by RT-qPCR remains biased as viral shedding and infectivity are not discerned. Thus, we aimed to develop a rapid viability RT-qPCR procedure to infer SARS-CoV-2 infectivity in clinical specimens and environmental samples. We screened monoazide dyes and platinum compounds as viability molecular markers on five SARS-CoV-2 RNA targets. A platinum chloride-based viability RT-qPCR was then optimized using genomic RNA, and inactivated SARS-CoV-2 particles inoculated in buffer, stool, and urine. Our results were finally validated in nasopharyngeal swabs from persons who tested positive for COVID-19 and in wastewater samples positive for SARS-CoV-2 RNA. We established a rapid viability RT-qPCR that selectively detects potentially infectious SARS-CoV-2 particles in complex matrices. In particular, the confirmed positivity of nasopharyngeal swabs following the viability procedure suggests their potential infectivity, while the complete prevention of amplification in wastewater indicated either non-infectious particles or free RNA. The viability RT-qPCR approach provides a more accurate ascertainment of the infectious viruses detection and it may complement analyses to foster risk-based investigations for the prevention and control of new or re-occurring outbreaks with a broad application spectrum.

The COVID-19 pandemic has posed a significant global threat, leading to several initiatives for its control and management. One such initiative involves wastewater-based epidemiology, which has gained attention for its potential to provide early warning of virus outbreaks and real-time information on its spread. In this study, wastewater samples from two wastewater treatment plants (WWTPs) located in the southeast of Spain (region of Murcia), namely Murcia, and Cartagena, were analyzed using RT-qPCR and high-throughput sequencing techniques to describe the evolution of SARS-CoV-2 in the South-East of Spain. Additionally, phylogenetic analysis and machine learning approaches were applied to develop a pre-screening tool for the identification of differences among the variant composition of different wastewater samples. The results confirmed that the levels of SARS-CoV-2 in these wastewater samples changed concerning the number of SARS-CoV-2 cases detected in the population, and variant occurrences were in line with clinical reported data. The sequence analyses helped to describe how the different SARS-CoV-2 variants have been replaced over time. Additionally, the phylogenetic analysis showed that samples obtained at close sampling times exhibited a higher similarity than those obtained more distantly in time. A second analysis using a machine learning approach based on the mutations found in the SARS-CoV-2 spike protein was also conducted. Hierarchical clustering (HC) was used as an efficient unsupervised approach for data analysis. Results indicated that samples obtained in October 2022 in Murcia and Cartagena were significantly different, which corresponded well with the different virus variants circulating in the two locations. The proposed methods in this study are adequate for comparing consensus sequence types of the SARS-CoV-2 sequences as a preliminary evaluation of potential changes in the variants that are circulating in a given population at a specific time point.

Since the dawn of the Internet, technology has played a crucial role in all spheres. In particular, in the educational and research world, the use of Information and Communication Technologies (ICTs) has greatly advanced, making a complete transformation in the methodologies used. Thus, virtual research environments are considered essential these days for those scholars and researchers who want to advance their investigations in the field of Spanish as a second language (SL2) or foreign language (SFL) (Allan, 2009; Mairal-Usón & Faber, 2020; Whishart & Thomas, 2017). The book e-Research y español LE/L2: Investigar en la era digital, edited by Mar Cruz Piñol (2021), deals jointly with the contributions to SL2/SFL from three diverse fields, i.e., library science, corpus linguistics, and digital editing. This publication provides a new, interdisciplinary, and international vision combining theory with case studies.

El presente artículo analiza la contabilidad ambiental en empresas de servicios de transporte de carga en Colombia. Expone percepción de gerentes y contadores públicos sobre la influencia de sus procesos misionales en la implementación de la contabilidad ambiental en sus empresas, es decir, en la incorporación en los reportes financieros, de información cuantitativa o cualitativa medida o presentada en unidades monetarias o no monetarias, sobre impactos ambientales causados por su actividad empresarial. La investigación se desarrolló con una metodología de corte mixta, transversal y la información se recolectó mediante una encuesta aplicada a gerentes y contadores de empresas de transporte de carga en una ciudad periférica de Colombia. Los resultados indican que las empresas no reconocen en la contabilidad o en informes financieros los impactos ambientales generados por la actividad realizada. Resalta también que actores como usuarios de la información contable (inversionistas, clientes, competidores o entidades gubernamentales de supervisión) no exigen información financiera de tipo ambiental. En conclusión, no se contemplan activos o pasivos ambientales ni costos ambientales asociados a la operación empresarial por omisión o ignorancia de contadores y gerentes.

Las investigaciones en el aprendizaje y enseñanza de las matemáticas a nivel universitario no se focalizan únicamente en la transición del Bachillerato a los primeros años de la universidad, sino también en matemáticas más avanzadas. El monográfico que se presenta en esta ocasión toma en consideración la necesidad de acercar los resultados de investigación en educación matemática en la universidad a sus lectores.

En este artículo se usa la teoría Acción-Proceso-Objeto-Esquema (APOE) para examinar la tematización del Esquema de derivada y el papel que juegan los mecanismos de equilibración de dicho Esquema a través de la evidencia mostrada por estudiantes avanzados al enfrentar tareas diseñadas para confrontar el equilibrio de sus Esquemas y obtener evidencia de su posible tematización. Esta investigación contribuye al estudio de la tematización de un Esquema al enfocarse en los mecanismos que pueden ponerse en juego cuando los estudiantes requieren hacer Acciones sobre su Esquema de derivada. Los resultados del estudio muestran evidencias que hacen visible el papel que los mecanismos de acomodación y asimilación juegan en las estrategias de los estudiantes para re-equilibrar su Esquema y demostrar su tematización. Algo que no ha recibido atención previa.

Wastewater discharge to the environment or its reuse after sanitization poses a concern for public health given the risk of transmission of human viral diseases. However, estimating the viral infectivity along the wastewater cycle presents technical challenges and still remains underexplored. Recently, human-associated crAssphage has been investigated to serve as viral pathogen indicator to monitor fecal impacted water bodies, even though its assessment as biomarker for infectious enteric viruses has not been explored yet. To this end, the occurrence of potentially infectious norovirus genogroup I (GI), norovirus GII, hepatitis A virus (HAV), rotavirus A (RV), and human astrovirus (HAstV) along with crAssphage was investigated in influent and effluent water sampled in four wastewater treatment plants (WWTPs) over 1 year by a PMAxx-based capsid integrity RT-qPCR assay. Moreover, influent and effluent samples of a selected WWTP were additionally assayed by an in situ capture RT-qPCR assay (ISC-RT-qPCR) as estimate for viral infectivity in alternative to PMAxx-RT-qPCR. Overall, our results showed lower viral occurrence and concentration assessed by ISC-RT-qPCR than PMAxx-RT-qPCR. Occurrence of potentially infectious enteric virus was estimated by PMAxx-RT-qPCR as 88–94% in influent and 46–67% in effluent wastewaters with mean titers ranging from 4.77 to 5.89, and from 3.86 to 4.97 log10 GC/L, with the exception of HAV that was sporadically detected. All samples tested positive for crAssphage at concentration ranging from 7.41 to 9.99 log10 GC/L in influent and from 4.56 to 6.96 log10 GC/L in effluent wastewater, showing higher mean concentration than targeted enteric viruses. Data obtained by PMAxx-RT-qPCR showed that crAssphage strongly correlated with norovirus GII (ρ = 0.67, p < 0.05) and weakly with HAstV and RV (ρ = 0.25–0.30, p < 0.05) in influent samples. In effluent wastewater, weak (ρ = 0.27–0.38, p < 0.05) to moderate (ρ = 0.47–0.48, p < 0.05) correlations between crAssphage and targeted viruses were observed. Overall, these results corroborate crAssphage as an indicator for fecal contamination in wastewater but a poor marker for either viral occurrence and viral integrity/infectivity. Despite the viral load reductions detected in effluent compared to influent wastewaters, the estimates of viral infectivity based on viability molecular methods might pose a concern for (re)-using of treated water.

La adquisición de un segundo idioma es un constructo complejo en el cual no sólo factores cognitivos juegan un papel crucial, sino también afectivos. En las últimas décadas, el análisis de los factores afectivos en el aprendizaje de segundas lenguas e idiomas extranjeros ha ganado prominencia. Diversas investigaciones han demostrado una fuerte correlación entre el aprendizaje de lenguas y aspectos como la personalidad, la motivación, la actitud o la ansiedad (p. ej., Gardner, 2020; Hewitt & Stephenson, 2011; MacIntyre & Gardner, 1989). El objetivo de este artículo es examinar si el nivel de ansiedad causado por el aprendizaje de lenguas extranjeras (FLA) podría disminuir usando mundos virtuales tales cómo Second Life (SL) para la enseñanza de idiomas. Esta investigación compara los niveles de FLA de un Grupo Experimental (EG), que completó tres actividades a través de SL, con un Grupo de Control (CG), que completó las mismas actividades en el aula tradicional. Los resultados indican que los niveles de FLA de los participantes en el EG disminuyeron a medida que las clases avanzaban en comparación con los participantes en el CG. Además, las conclusiones sugieren que la confianza de los participantes que trabajaban en SL aumentó con el paso del tiempo. Este incremento en la confianza de los alumnos podría atribuirse al papel crucial que desempeña el anonimato en los mundos virtuales.

The aim of this research is to characterize the understanding of the numerical sequence concept in high school students (14-16 years old). The study draws on the APOS theory, which considers how students use mathematical elements, the relationships established between them, theirs modes of representation and the cognitive structures that are showed in the resolution of mathematical tasks. Our methodology is qualitative, using data from two questionnaires of diverse nature. The different levels of understanding of the scheme of the concept of numerical sequence were characterized taking into consideration the analysis of the two questionnaires.

Introducción: Existen numerosos tipos de fracaso en las restauraciones cerámicas en base de circonio, cerámicas sobre base o núcleo de circonio siendo el agrietamiento uno de los más frecuentes. Objetivo: Describir las asociaciones de los fracasos en las prótesis con núcleo de circonio y laminadas con cerámicas de recubrimiento. Métodos: Se realizó una revisión bibliográfica sobre los fracasos de la cerámica de restauraciones de circonio y sus mecanismos en MEDLINE, PubMed y SciELO. La búsqueda se orientó a artículos publicados fundamentalmente en los últimos 5 años sin hacer distinciones de idioma. Los tópicos consultados en la revisión estuvieron referidos a estudios experimentales en humanos, animales e in vitro que incluyeran los tópicos de fracaso, longevidad de restauraciones, mecanismos de fracaso, fracturas y tipos de ellas. Análisis e integración de la información: Se profundiza en el tema de los fracasos de la cerámica de restauraciones de circonio. La causa de fracaso más prevalente es el agrietamiento, en sus distintos grados que alcanzan hasta tasas de 16 % a los 5 años, lo que representa una causa de fracaso relevante. No existe evidencia de unión química entre el núcleo de circonio y la cerámica de revestimiento, esto explicaría la génesis de las fracturas. Conclusiones: Las complicaciones más comunes encontradas en restauraciones de núcleo de circonio recubiertas con porcelana están asociadas con el agrietamiento de la porcelana de recubrimiento, a las fracturas del núcleo de circonio que se asocian fundamentalmente a traumas y hábitos parfuncionales; la pérdida de retención y problemas endodónticos.

Introduction: In implant therapy, adequate alveolar bone volume and favorable alveolar ridge architecture are important considerations to obtain positive functional and esthetic rehabilitation. Objective: Describe prosthodontic treatment in an extraction socket with advanced palatal bone resorption secondary to a root fracture through the use of an implant-supported single fixed prosthesis. Principal case data: 39-year-old male patient, without systemic disease, and completely dentate with no occlusal parafunction. Radiographic examination showed the presence of advanced palatal bone resorption, almost total loss of the palatal plate in all its extension secondary to a root fracture of the maxillary left lateral incisor and a large osteolytic area on the palatal aspect of the root. The procedure consisted in extraction of the maxillary left lateral incisor and eventual regeneration of the palatal plate using a resorbable collagen membrane, which was adapted to the bone defect. Then, particulate cortical bone allograft was compacted into the site. Four months after grafting the extraction site, an implant was placed. Six months after implant placement osseointegration was confirmed, and after several stages restoration with a zirconium dioxide abutment and a full ceramic crown was obtained and followed up for 2 years. Conclusions: Regeneration of the palatal plate was possible through the use of particulate cortical bone allograft and a resorbable collagen membrane adapted to the bone defect and placed in position to recreate the palatal plate. This allowed installation of an implant 4 months after the procedure. This technique allowed esthetic and functional results using a single fixed prosthesis.

The results of the research related to the learning process of the derivative notion show that its understanding is very complex and that only a significant number of students acquire a partial comprehension of the concept. In this context, this research presents an exploratory/confirmatory analysis in which we identify and characterize, through mixed analysis methods, the different sub-levels of development of the derivative schema that university students previously instructed in Differential Calculus managed to reach. The results show how useful these methods are in this study, since they made it possible to identify the 9 sub-levels of development and to characterize 5 of them according to the dominant variables and their associated mathematical elements.

Microalgae have demonstrated a large potential in biotechnology as a source of various macromolecules (proteins, carbohydrates, and lipids) and high-added value products (pigments, poly-unsaturated fatty acids, peptides, exo-polysaccharides, etc.). The production of biomass at a large scale becomes more economically feasible when it is part of a biorefinery designed within the circular economy concept. Thus, the aim of this critical review is to highlight and discuss challenges and future trends related to the multi-product microalgae-based biorefineries, including both phototrophic and mixotrophic cultures treating wastewater and the recovery of biomass as a source of valuable macromolecules and high-added and low-value products (biofertilizers and biostimulants). The therapeutic properties of some microalgae-bioactive compounds are also discussed. Novel trends such as the screening of species for antimicrobial compounds, the production of bioplastics using wastewater, the circular economy strategy, and the need for more Life Cycle Assessment studies (LCA) are suggested as some of the future research lines.

Medicinal and aromatic plants (MAPs) are potential sources of natural bioactive phytochemical compounds of an incredible worth for the food industry, such as polyphenols. Lamiaceae medicinal and aromatic plants from Granada’s high plateau, concretely Origanum bastetanum, Thymus zygis gracilis, Thymus longiflorus, Thymus membranaceus and Ziziphora hispanica, were evaluated under different conventional solid–liquid extraction conditions to obtain extracts enriched in bioactive compounds. Phenolic profile was detected by HPLC-QTOF-MS, identifying a high abundance of bioactive constituents. Furthermore, antioxidant and antiviral activities of the mentioned plants were studied as biological properties of interest for the improvement of food shelf-life. Thus, Origanum bastetanum showed the highest antioxidant potential for all assays. Antiviral activity was also tested against some important foodborne viruses, feline calicivirus (FCV), murine norovirus (MNV) and hepatitis A virus (HAV), with the highest activity obtained for Ziziphora hispanica, Thymus longiflorus and Origanum bastetanum. This research proposes the studied plants as rich sources of bioactive compounds with potential use as preservatives in the food industry.

Conventional aerobic biological treatments of digested organic fraction of municipal solid waste (OFMSW) slurries–usually conventional activated sludge or aerobic membrane bioreactor (AeMBR)–are inefficient in terms of energy and economically costly because of the high aeration requirements and the high amount of produced sludge. In this study, the supernatant obtained after the anaerobic digestion of OFMSW was treated in a mesophilic demo-scale anaerobic membrane bioreactor (AnMBR) at cross flow velocities (CFVs) between 1 and 3.5 m⋅s–1. The aim was to determine the process performance of the system with an external ultrafiltration unit, in terms of organic matter removal and sludge filterability. In previous anaerobic continuous stirred tank reactor (CSTR) tests, without ultrafiltration, specific gas production between 40 and 83 NL CH4⋅kg–1 chemical oxygen demand (COD) fed and removals in the range of 10–20% total COD (tCOD) or 59–77% soluble COD (sCOD) were obtained, for organic loading rates (OLR) between 1.7 and 4.4 kg COD⋅m–3reactor d–1. Data helped to identify a simplified model with the aim of understanding and expressing the process performance. Methane content in biogas was in the range of 74–77% v:v. In the AnMBR configuration, the COD removal has been in the ranges of 15.6–38.5 and 61.3–70.4% for total and sCOD, respectively, with a positive correlation between solids retention time (SRT, ranging from 7.3 to 24.3 days) and tCOD removal. The constant used in the model expressing inhibition, attributable to the high nitrogen content (3.6 ± 1.0 g N-NH4+⋅L–1), indicated that this inhibition decreased when SRT increased, explaining values measured for volatile fatty acids concentration, which decreased when SRT increased and OLR, measured per unit of volatile suspended solids in the reactor, decreased. The alkalinity was high enough to allow a stable process throughout the experiments. Constant CFV operation resulted in excessive fouling and sudden trans-membrane pressure (TMP) increases. Nevertheless, an ultrafiltration regime based on alternation of CFV (20 min with a certain CFVi and then 5 min at CFVi + 1 m⋅s–1) allowed the membranes to filter at a flux (standardized at 20°C temperature) ranging from 2.8 to 7.3 L⋅m–2⋅h–1, over 331 days of operation, even at very high suspended solids concentrations (>30 g total suspended solids⋅L–1) in the reactor sludge. This flux range confirms that fouling is the main issue that can limit the spread of AnMBR potential for the studied stream. No clear correlation was found between CFV or SRT vs. fouling rate, in terms of either TMP⋅time–1 or permeability⋅time–1. As part of the demo-scale study, other operational limitations were observed: irreversible fouling, scaling (in the form of struvite deposition), ragging, and sludging. Because ragging and sludging were also observed in the existing AeMBR, it can be stated that both are attributable to the stream and to the difficulty of removing existing fibers. All the mentioned phenomena could have contributed to the high data dispersion of experimental results.

Resultados de investigaciones previas han puesto de manifiesto la complejidad de la transferencia de conocimiento entre Matemáticas y Física. El objetivo de este artículo es caracterizar las manifestaciones de transferencia o evidencia de conocimiento entre ambas áreas en estudiantes de Bachillerato (16-18 años) cuando resuelven problemas sobre la velocidad media. El enfoque metodológico es cualitativo. Nuestro instrumento de recogida de datos es dos tareas sobre velocidad media en distintos registros de representación, que realizaron un total de 119 estudiantes españoles. Los resultados han permitido identificar cuatro grupos de estudiantes en relación con la evidencia de conocimiento de la tasa de variación media y la velocidad media, puesta de manifiesto en la resolución de las tareas. Un primer grupo de estudiantes que no usa la velocidad media ni la tasa de variación media, un segundo grupo que usa la tasa de variación media, un tercer grupo que evidencia conocimiento de ambas áreas a partir de determinados datos y un cuarto grupo que manifiesta la transferencia de conocimiento entre ambas áreas a partir de cualquier tipo de datos. Estos resultados nos han permitido caracterizar una posible progresión en la transferencia de conocimiento entre ambas áreas en resolución de tareas sobre velocidad media.

There is no doubt that the use of Internet for purchasing products and services has constituted a crucial change in how people go about buying them. In the era of digital transformation, the possibility of accessing information provided by other users about their personal experiences has taken on more weight in the selection and buying processes. On these lines, traditional word-of-mouth (WOM) has given way to electronic word-of-mouth (eWOM), which constitutes a major social change. This behavior is particularly relevant in the services area, where potential users cannot in advance assess what is on offer. There is an abundant literature analyzing the effects of eWOM on different variables of interest in this sector. However, little is known about the factors that determine eWOM. Thus, the main objective of the present paper is to analyze the impact of two variables (objective quality and perceived quality) on eWOM. Both of them are crucial for potential customers in the process of finding hotel accommodations and they can motivate people to make such comments. The results demonstrate that these variables truly have a significant impact on whether or not users make comments on line. Moreover, it proved possible to observe certain differences according to the profile of the tourist involved and the destination where the hotel is located. In the current changing environment, this information is of great use for hotel managers in order to design strategies according to the type of guest they wish to attract.

The International Virus Bioinformatics Meeting 2022 took place online, on 23–25 March 2022, and has attracted about 380 participants from all over the world. The goal of the meeting was to provide a meaningful and interactive scientific environment to promote discussion and collaboration and to inspire and suggest new research directions and questions. The participants created a highly interactive scientific environment even without physical face-to-face interactions. This meeting is a focal point to gain an insight into the state-of-the-art of the virus bioinformatics research landscape and to interact with researchers in the forefront as well as aspiring young scientists. The meeting featured eight invited and 18 contributed talks in eight sessions on three days, as well as 52 posters, which were presented during three virtual poster sessions. The main topics were: SARS-CoV-2, viral emergence and surveillance, virus–host interactions, viral sequence analysis, virus identification and annotation, phages, and viral diversity. This report summarizes the main research findings and highlights presented at the meeting.

Coronaviruses (CoVs) cause severe respiratory, enteric, and systemic infections in a wide range of hosts, including humans and animals. Porcine epidemic diarrhea virus (PEDV), a member of the Coronaviridae family, is the etiological agent of porcine epidemic diarrhea (PED), a highly contagious intestinal disease affecting pigs of all ages. In this study, we optimized a viability real-time reverse transcriptase polymerase chain reaction (RT-qPCR) for the selective detection of infectious and heat-inactivated PEDV. PEMAX™, EMA™, and PMAxx™ photoactivable dyes along with PtCl4 and CDDP platinum compounds were screened as viability markers using two RT-qPCR assays: firstly, on PEDV purified RNA, and secondly on infectious and thermally inactivated virus suspensions. Furthermore, PMAxx™ pretreatment matched the thermal inactivation pattern obtained by cell culture better than other viability markers. Finally, we further optimized the pretreatment by coupling viability markers with Triton X-100 in inoculated serum resulting in a better estimation of PEDV infectivity than RT-qPCR alone. Our study has provided a rapid analytical tool based on viability RT-qPCR to infer PEDV infectivity with potential application for feed and feed ingredients monitoring in swine industry. This development would allow for greater accuracy in epidemiological surveys and outbreak investigations.

Introduction: A lot of research has been done on dental implants, however the osseointegrable area is still a little discussed topic in the scientific literature. Objective: To desing this area oseointegrable performs vital importance for the capture of clinical decisions. Material and Method: The areas of the implants, the royal(real) one calculated approximately on the basis of models of implants of size four times, using the formulae known for mantles of cylinder, trunks of cone, circle (between(among) others) and applying linear relations for the heights and for the diameters to the square (assimilation to model(models') theory) and using a Metal gauge, Magnifying glass and Escalímetro. The implants were divided in sectors according to his(her,your) different geometric configuration, which sum of surfaces allowed to obtain the total area of the implant. They were compared with the theoretical total area of the same implants. Then the information was extrapolated for all the models according to his(her,your) particular dimensions. Results: The areas obtained for implants Type Screw and Conical Type (diameter / length in mm) were respectively: 3,75/7=129mm2; 3,75/13=234mm2; 3,75/15=270mm2; 4/15=306mm2; 5/7=224mm2 and 3,5/13=143mm2; 4,3/10=166mm2; 4,3/13=215mm2; 4,3/16=265mm2; Conclusion: Implants of a similar size but of different design present a minor osseointegrated area like conical implants comparative with cilinder implants.

Los principales patógenos víricos que podemos ad­quirir ingiriendo alimentos contaminados son los norovirus, el virus de la hepatitis A y el virus de la hepatitis E que se propagan principalmente a través de la vía fecal oral. En los últimos años, la incidencia de brotes de transmisión alimentaria causados por estos patógenos ha experimentado un aumento considerable, en parte debido al comercio globalizado y a los cambios en los hábitos de consumo. Las matrices alimentarias que mayor riesgo representan para el consumidor son los moluscos bivalvos, ve­getales de IV gama, frutas tipo baya y platos listos para comer. Actualmente las técnicas moleculares son las más habituales para la detección de estos patógenos en alimentos, aunque toda­vía existen dudas acerca del significado de la presencia de estos genomas víricos en términos de seguridad alimentaria. La infec­tividad de estos patógenos en alimentos viene también determi­nada por su elevada persistencia ambiental y por su resistencia a los tratamientos aplicados para la conservación de los alimentos.

Hepatitis E virus (HEV), particularly zoonotic genotype 3, is present in environmental waters worldwide, especially in industrialized countries. Thus, monitoring the presence of HEV in wastewater treatment plants (WWTPs) is an emerging topic due to the importance of reusing water on a global level. Given the limited data, this study aimed to monitor the occurrence of HEV in influent and effluent water in waste- and drinking-water treatment plants (WWTPs and DWTPs). To this end, different procedures to concentrate HEV in influent and effluent water from WWTPs and DWTPs were initially evaluated. The evaluated procedures resulted in average HEV recoveries of 15.2, 19.9, and 16.9% in influent, effluent, and drinking water samples, respectively, with detection limits ranging from 103 to 104 international units (IU)/L. Then, a one-year pilot study was performed to evaluate the performance of the selected concentration method coupled with three RT-qPCR assays in influent and effluent water samples from four different WWTPs. HEV prevalence in influent water varied based on both the RT-qPCR assay and WWTP, while HEV was not detected in effluent water samples. In addition, HEV prevalence using only RT-qPCR3 was evaluated in influent (n = 62) and effluent samples (n = 52) from four WWTPs as well as influent (n = 28) and effluent (n = 28) waters from two DWTPs. The present study demonstrated that HEV circulated in the Valencian region at around 30.65% with average concentrations of 6.3 × 103 IU/L. HEV was only detected in influent wastewater samples, effluent samples from WWTPs and influent and effluent samples from DWTPs were negative. However, given that the infective dose in waterborne epidemics settings is not yet known and the low sensibility of the assay, unfortunately, no direct conclusion could be achieved on the risk assessment of environmental contamination.

ABSTRACT Introduction: chronic kidney disease is a frequent complication after liver transplantation. The use of calcineurin inhibitors is one of the causes of this complication. Current immunsuppression regimens that reduce the use of calcineurin inhibitors may be associated with an improved preservation of renal function. Objective: the study aimed to assess the evolution of renal function after liver transplantation in the current routine clinical practice. Methods: an observational, prospective, multicenter study in adult liver transplant recipients was performed. Two hundred and thirty patients with a good renal function before transplantation were assessed six months post-transplantation (baseline) and every six months until month 30. Results: at baseline, 32% of the patients had a reduction in the glomerular filtration rate below 60 ml/min/1.73 m2. The mean glomerular filtration rate increased from 72.3 to 75.6 ml/min/1.73 m2 at baseline and month 30 respectively (p < 0.01). The mean serum creatinine levels (mg/dl) decreased from 1.13 to 1.09 (p < 0.01). The percentage of patients with stage 3 chronic kidney disease decreased from 31.7% to 26.4%, whereas the percentage of patients with stage 4 remained unchanged (0.4% at baseline and 0.5% at month 30). No patients progressed to end-stage kidney disease that required dialysis or renal transplantation. Conclusion: in the routine clinical practice, a moderate deterioration of renal function is frequent after liver transplantation. However, advanced chronic kidney disease is infrequent in patients with a good pre-transplant renal function.

L’objectiu és examinar en quina mesura la identificació de la coordinació de les aproximacions en el domini i el rang d’una funció és considerat un avançament conceptual (KDU; Simon, 2006) en la comprensió del concepte de límit d’una funció pel futur professorat. 25 estudiants per ser mestres de matemàtiques a l’ESO van anticipar respostes d’estudiants de batxillerat a problemes sobre límits d’una funció que mostraven diferents característiques de la comprensió i van posar problemes per sostenir el progrés conceptual dels i de les estudiants. Els resultats mostren que identificar la coordinació de les aproximacions en el domini i el rang com un KDU va permetre al futur professorat considerar progressions en l’aprenentatge i fer-ne les seves propostes d’ensenyament.

The virological quality of process water (PW) used by the produce industry has received limited attention. As a first step to overcoming technical limitations in monitoring viruses in PW, the analytical performance of ultrafiltration was assessed to concentrate viral particles from 20 L of spiked PW. The selected method used for sample concentration of PW was carefully validated, thus enabling the accurate quantification and estimation of viral titers of human enteric viruses and phages. PW from the produce industry was collected periodically from the washing tanks of commercial facilities. The analysis of coliphages was performed by plaque assay, while the occurrence of enteric viruses and crAssphage was determined by molecular techniques. Significant differences in the physicochemical composition of PW, mostly due to the different nature of fresh produce types and differences in the sanitizer used in commercial operation, were observed. Accumulation of crAssphage and coliphages was observed in PW, but correlation with human enteric viruses was not possible due to the low prevalence of these pathogens in the PW analyzed. The obtained results showed that depending on the type of product washed, the product/water ratio and the residual concentrations of the sanitizers, the prevalence and concentration of bacteriophages changed significantly.

El objetivo de esta investigación es la caracterización de la compresión del concepto de sucesión numérica en los estudiantes de segundo ciclo de Educación Secundaria Obligatoria (14-16 años), considerando como marco teórico APOS, a través del uso que hacen los estudiantes de los elementos matemáticos, las relaciones que se establecen entre ellos, los modos de representación y los modos de conocer que se ponen de manifiesto en la resolución de las tareas matemáticas que se les proponen. Nuestra metodología es cualitativa, usando datos provenientes de dos cuestionarios de distinta naturaleza. A partir del análisis conjunto de los dos cuestionarios contestados por cada estudiante, se caracterizan los distintos niveles de comprensión del esquema del concepto de sucesión como lista numérica.

Los resultados de investigaciones relacionadas con el aprendizaje del concepto de derivada constatan que su comprensión resulta muy compleja y que una cantidad significativa de estudiantes solo logra una construcción parcial del concepto. Desde este contexto, en esta investigación presentamos un análisis exploratorio/confirmatorio en el que identificamos y caracterizamos, por medio de métodos de análisis mixtos, los distintos subniveles de desarrollo del esquema de derivada que alcanzaron estudiantes universitarios con instrucción previa en cálculo diferencial. Los resultados muestran la utilidad del uso de estos métodos que, en este estudio, permitieron identificar los 9 subniveles de desarrollo y caracterizar 5 de ellos en función de las variables dominantes y sus elementos matemáticos asociados.

AimWe describe the effectiveness and safety of the interferon-free regimen ombitasvir/paritaprevir/ritonavir plus dasabuvir with or without ribavirin (OBV/PTV/r ± DSV ± RBV) in a nationwide representative sample of the hepatitis C virus (HCV) monoinfected and human immunodeficiency virus-1/hepatitis C virus (HIV/HCV) coinfected population in Spain.Material and methodsData were collected from patients infected with HCV genotypes 1 or 4, with or without HIV-1 coinfection, treated with OBV/PTV/r ± DSV ± RBV at 61 Spanish sites within the initial implementation year of the first government-driven "National HCV plan." Effectiveness was assessed by sustained virologic response at post-treatment week 12 (SVR12) and compared between monoinfected and coinfected patients using a non-inferiority margin of 5% and a 90% confidence interval (CI). Sociodemographic and clinical characteristics or patients and adverse events (AEs) were also recorded.ResultsOverall, 2,408 patients were included in the intention-to-treat analysis: 386 (16%) were patients with HIV/HCV. Patient selection reflected the real distribution of patients treated in each participating region in Spain. From the total population, 96.6% (95% CI, 95.8-97.3%) achieved SVR12. Noninferiority of SVR12 in coinfected patients was met, with a difference between monoinfected and coinfected patients of -2.2% (90% CI, -4.5% - 0.2%). Only genotype 4 was associated with non-response to OBV/PTV/r ± DSV ± RBV treatment (pConclusionsOur results confirm that OBV/PTV/r ± DSV ± RBV is effective and generally well tolerated in a representative sample of the HCV monoinfected and HCV/HIV coinfected population in Spain within the experience of a national strategic plan to tackle HCV.

Resumen Este estudio analiza la importancia del tratamiento de puntos de no-derivabilidad en la tematización del esquema de derivada. Para ello, se consideró el marco propuesto por la teoría APOE, a través del uso y conexiones lógicas que los estudiantes universitarios establecen entre los elementos matemáticos y los modos de representación cuando resuelven tareas sobre derivada. Se utilizaron dos instrumentos: el primero fue un cuestionario conformado por tres tareas propuestas en distintos modos de representación, en cuya resolución era necesaria la utilización de los elementos matemáticos constitutivos del concepto de derivada; este instrumento fue aplicado a los 40 estudiantes participantes del estudio. El segundo instrumento correspondió a una entrevista clínica que se centró en el análisis de las respuestas de los estudiantes en relación con el tratamiento que realizan en los puntos de no-derivabilidad en derivadas sucesivas. Esta entrevista clínica se aplicó a 5 de los 9 estudiantes clasificados en el nivel de desarrollo Trans-derivada. Los resultados del análisis constatan que la coherencia del esquema es fundamental para identificar un esquema tematizado. Además, se observó el importante papel desempeñado por el análisis de los puntos de no-derivabilidad en la conexión y el tránsito entre derivadas de diferentes órdenes, especialmente desde el modo de representación gráfico, lo cual puede ser un factor que favorece la tematización del esquema de derivada.

In the last decades, berries have been identified as important vehicles for the transmission of foodborne viruses and different strategies are being explored to eliminate or reduce viral contamination in these fruits. The aim of this work was to develop novel edible coatings with antiviral properties for inactivating and reducing murine norovirus (MNV). Firstly, the effect of gelatin (G) addition on Persian gum (PG) films was studied in terms of microstructural, mechanical, optical, and water barrier properties. The following PG:G ratios were considered: 100:0, 75:25, 50:50, 25:75, and 0:100. Microstructure analysis revealed the compatibility of both hydrocolloids since no phase separation was observed. The addition of G to PG films provided stiffer and more deformable films than pure PG, with lower water vapor permeability values. Specifically, films prepared with 50:50 PG:G ratio presented better mechanical and barrier performance. Interestingly, pure PG showed antiviral activity on murine norovirus, probably due to the presence of some impurities (mainly tannins). Adding allyl isothiocyanate (AITC) enhanced the PG antiviral activity at refrigerated temperatures in blueberries, not being affected by the AITC concentration. This effect was not observed at ambient temperature, probably due to the volatilization of AITC.

Hepatitis E virus (HEV) is one of the causative agents of water-borne human viral hepatitis and considered in Europe an emerging zoonotic pathogen. Analysis of bottled water through a standard method validated for HEV can contribute towards the risk management of this hazard. Putting some recent reports by the European Food Safety Authority in place, this study aimed to assess the performance of the concentration and extraction procedures described in ISO 15216-1:2017 for norovirus and hepatitis A virus on HEV detection. Following the ISO recommendation, the bottled water samples were spiked using serially diluted HEV fecal suspensions together with mengovirus as process control and concentrated by filtration via positively charged nylon membranes. In order to extract viral RNA from the resulting concentrates, two different methods were compared in this study: The one recommended in the ISO norm, NucliSens® MiniMag® system (NS), and an alternative commercially available kit NucleoSpin®RNA virus kit (MN). Finally, three reverse transcription quantitative PCR (RT-qPCR) assays were used to quantify HEV titers. The evaluated procedures resulted in average HEV recoveries of 14.08 ± 4.90% and 3.58 ± 0.30% for the MN and NS methods, respectively. The limit of detection (LoD95%) was 1.25 × 104 IU/L for both extraction methods combined with the three RT-qPCR assays tested, with the exception of NS extraction coupled with RT-qPCR1 that showed a LoD95% of 4.26 × 103 IU/L. The method characteristics generated in this study support the limited suitability of the ISO 15216-1:2017 concentration procedure coupled with the evaluated RT-qPCR assays for detecting HEV in bottled water.

An antimicrobial polymeric bilayer structure based on the application of an acrylic coating containing hollow zinc oxide nanotubes over a polymeric substrate was developed in this work. Firstly, zinc oxide nanotubes (ZnONT) were obtained by an atomic layer deposition (ALD) process over electrospun polyvinyl alcohol nanofibers followed by polymer removal through calcination with the purpose of obtaining antimicrobial nanostructures with a high specific area. Parameters of electrospinning, ALD, and calcination processes were set in order to obtain successfully hollow zinc oxide nanotubes. Morphological studies through scanning electron microscopy (SEM) and transmission electron microscopy (TEM) microscopies confirmed the morphological structure of ZnONT with an average diameter of 180 nm and thickness of approximately 60 nm. Thermal and X-ray diffraction (XRD) analyses provided evidence that calcination completely removed the polymer, resulting in a crystalline hexagonal wurtzite structure. Subsequently, ZnONT were incorporated into a polymeric coating over a polyethylene extruded film at two concentrations: 0.5 and 1 wt. % with respect to the polymer weight. An antimicrobial analysis of developed antimicrobial materials was performed following JIS Z2801 against Staphylococcus aureus and Escherichia coli. When compared to active materials containing commercial ZnO nanoparticles, materials containing ZnONT presented higher microbial inhibition principally against Gram-negative bacteria, whose reduction was total for films containing 1 wt. % ZnONT. Antiviral studies were also performed, but these materials did not present significant viral reduction.

The hepatitis E virus (HEV) is an emerging pathogen showing a considerable increase in the number of reported cases in Europe mainly related to the ingestion of contaminated food. As with other relevant viral foodborne pathogens, real-time reverse transcriptase polymerase chain reaction (RT-qPCR) is the gold standard for HEV detection in clinical, food, and environmental samples, but these procedures cannot discriminate between inactivated and potentially infectious viruses. Thus, the aim of this study was to develop a viability PCR method to discriminate between native, heat-, and high-pressure processing (HPP)-treated HEV using the hepatitis A virus (HAV) as a cultivable surrogate. To this end, different concentrations of viability markers (PMAxx and platinum chloride, PtCl4) were screened firstly on purified viral RNA using different RT-qPCR assays. Reductions of HEV RNA signals of >17.5, >15.0, and >15.5 quantification cycles (Cq) were reported for PtCl4 and 1.6, 2.9, and 8.4 Cq for PMAxx, clearly indicating a better performance of PtCl4 than PMAxx irrespective of the RT-qPCR assay used. The most efficient viability pretreatment (500 μM PtCl4 incubated at 5°C for 30 min) was then assessed on native, heat-, and HPP-treated HEV suspension. The optimized viability RT-qPCR discriminated successfully between native, heat-, and HPP-treated HEV, to different extents depending on the experimental conditions. In particular, approximately 2-log10 reduction was reported by PtCl4-RT-qPCR at both 72 and 95°C compared to the control. Additionally, both viability pretreatments were tested for HPP-treated HAV without success, while PtCl4-RT-qPCR completely eliminated (>5.6-log10 reduction) the RT-qPCR signals of HPP-treated HEV. Although this viability procedure may still overestimate infectivity, the PtCl4 pretreatment represents progress to better interpreting the quantification of intact HEV, and it could be included in molecular procedures used to quantify enteric viruses in food and environmental samples.

The aim of this study is to examine to what extent the identification of the coordination of approximations in the domain and in the range is considered a Key Developmental Understanding (KDU in Simon, 2006) by prospective teachers. 25 prospective secondary school mathematics teachers anticipated high school students’ answers to problems about the limit of a function showing different characteristics of understanding and proposed problems that would support students’ conceptual progress. Results show that identifying the coordination of the approximations in the domain and in the range as KDU allowed prospective teachers to consider progressions in students’ learning in order to support their teaching decisions.

Background and rational. Telaprevir-based therapy (TBT) has been extensively evaluated in clinical trials. So we designed a study to compare the efficacy and safety of TBT between patients with moderate fibrosis and those suffering from advanced fibrosis in clinical practice. A multicenter observational and ambispective study was conducted. It included 582 patients with chronic hepatitis C genotype 1, 214 with fibrosis F2, and 368 with F3/F4 (F3: 148; F4: 220).Results. The mean patient age was 55 years, 67% male. Type of prior response was 22% naïve, 57% relapsers, and 21% partial/null responders, 69% had high viral load (> 800,000 IU/mL). HCV genotypes were 1a (19%), 1b (69%), and 1 (12%), respectively. Sixty-five percent were non-CC IL28B genotype. Week-12 sustained virologic response (SVR12) was significantly higher among F2-naïve patients (78%) compared with F3/F4-naïve patients (60%; p = 0.039) and among F2 non-responders (67%) compared with F3/F4 non-responders (42%; p = 0.014). SVR12 among relapsers was remarkably high in both groups (F2:89% vs. F3/F4:78%). Severe anemia and thrombocytopenia were more frequent among patients with F3/F4 than those with F2 (p < 0.01). Overall, 132 patients (22%) discontinued treatment: 58 due to adverse effects, 42 due to the stopping-rule, and 32 due to breakthrough. Premature discontinuation was more frequent among patients with F3/F4 (p = 0.028), especially due to breakthrough (p < 0.001). Conclusions. This multicenter study demonstrates high efficacy and an acceptable safety profile with regard to TBT in F2-patients in clinical practice.

Els processos de construcció de coneixement matemàtic, com definir, són clau en l'activitat de «fer matemàtiques». La caracterització del seu aprenentatge és un tema rellevant en el camp d'investigació en educació matemàtica. En aquest treball, adoptant una perspectiva sociocultural, a través d'una anàlisi inductiu, hem identificat diferents situacions d'aprenentatge matemàtic. Aquestes situacions es caracteritzen a través de les eines teòriques procedents de la perspectiva sociocultural quan grups d'estudiants resolen tasques en un context geomètric. Els resultats mostren que determinades rutines juguen un paper rellevant en els procediments de canvi en el discurs matemàtic.

Posidonia oceanica waste biomass has been valorised to produce extracts by means of different methodologies and their bioactive properties have been evaluated. Water-based extracts were produced using ultrasound-assisted and hot water methods and classified according to their ethanol-affinity (E1: ethanol soluble; E2: non-soluble). Moreover, a conventional protocol with organic solvents was applied, yielding E3 extracts. Compositional and structural characterization confirmed that while E1 and E3 extracts were mainly composed of minerals and lipids, respectively, E2 extracts were a mixture of minerals, proteins and carbohydrates. All the extracts showed remarkably high antioxidant capacity, which was not only related to phenolic compounds but also to the presence of proteins and polysaccharides. All E2 and E3 extracts inhibited the growth of several foodborne fungi, while only E3 extracts decreased substantially the infectivity of feline calicivirus and murine norovirus. These results show the potential of P. oceanica waste biomass for the production of bioactive extracts.

Questions are essential in the construction of new knowledge by scientists. Nevertheless, students ask very few questions in usual classroom situations. In this paper we review the research work on question generation and describe three empirical studies conducted with students of different educational levels facing experimental devices. The aims were: 1) To stimulate and to analyse the questions asked by students when trying to understand the devices; 2) To probe the idea that most of the information seeking questions are originated by failed inferences; 3) To study the influence of the level of students’ knowledge on the questions asked. The procedure produced a significant quantity of information seeking questions, caused by the students’ awareness of misunderstanding. The results obtained support the taxonomy of questions proposed and show that higher knowledge students ask significantly more questions addressed to the scientific model construction than lower knowledge students. The results are replicated consistently.

El objetivo del trabajo fue describir y analizar las consecuencias psicosociales que sufren los hijos de madres que cumplen pena privativa de libertad, a partir de este logro hacer aporte para la conformación de un modelo carcelario femenino que dignifique la vida de las internas, considere su condición de madre y las implicaciones de todo esto, tanto para ella, como para sus hijos. El estudio fue de tipo descriptivo analítico, la metodología cualitativa y como técnicas la entrevista semiestucturada, análisis de contenido y el test de familia, se integró a través de la triangulación. Los entrevistados fueron niños de edad escolar (entre 7 y 12 años) cuyas madres se encuentran recluidas en el Anexo Femenino de la Cárcel Nacional de Maracaibo y los tutores legales quienes ejercen su guarda y custodia. Los resultados indican que los niños entrevistados, cuyas madres cumplen pena privativa de libertad, tienden a desarrollar dificultades psicológicas como: la ansiedad ante la separación, estrés y depresión; en lo social, tienen dificultades para la autorregulación, la regulación social y la autoestima. Se recomienda que el Estado genere programas que brinden a estos niños el debido amparo, protección y orientaciones psicosociales para superar dificultades devenidas de la privación, desarraigo de la madre y la familia

El objetivo de este artículo es describir, desde nuestra perspectiva, lo que ha implicado llevar a cabo un proyecto de investigación en nuestro campo. Para ello, nos apoyamos en uno de esos proyectos desarrollado por nuestro equipo, cuyo objetivo ha sido obtener información sobre el aprendizaje matemático de los alumnos de bachillerato. En particular, abordamos el estudio conjunto de los metaconceptos defi nir, probar y modelar, que nosotros consideramos muy relevantes en la construcción del conocimiento matemático. La descripción del proceso se realiza en base a cuatro etapas clave: identificación del problema, su consideración dentro de un marco adecuado y compatible con él, un diseño metodológico que permita resolverlo en forma coherente, y el acceso a unos resultados válidos, verifi cables y contrastables, que supongan un avance en el cuerpo de conocimiento científi co propio del campo considerado.

Los procesos de construcción de conocimiento matemático, como definir, son clave en la actividad de «hacer matemáticas». La caracterización de su aprendizaje es un tema relevante en el campo de investigación en educación matemática. En este trabajo, adoptando una perspectiva sociocultural, a través de un análisis inductivo, hemos identificado diferentes situaciones de aprendizaje matemático. Dichas situaciones se caracterizan a través de las herramientas teóricas procedentes de la perspectiva sociocultural cuando grupos de estudiantes resuelven tareas en un contexto geométrico. Los resultados muestran que determinadas rutinas juegan un papel relevante en los procedimientos de cambio en el discurso matemático.

Las preguntas forman parte esencial del trabajo que desarrollan los científicos para construir nuevo conocimiento. Sin embargo, los alumnos formulan un número muy escaso de preguntas en las situaciones usuales de aula. En este trabajo se realiza una revisión de las investigaciones realizadas sobre génesis de preguntas y se describen tres estudios empíricos realizados con estudiantes de diferentes niveles educativos ante dispositivos experimentales. Los objetivos fueron: 1) Estimular y analizar las preguntas de los estudiantes cuando intentan comprender los dispositivos; 2) Clasificar las preguntas en función de los tipos de inferencias que aparecen durante el procesamiento de la información; 3) Estudiar la influencia del nivel de conocimientos sobre las preguntas formuladas. El procedimiento produjo una cantidad aceptable de preguntas motivadas por conciencia de incomprensión de los estudiantes. Los resultados obtenidos apoyan la taxonomía de preguntas propuesta y muestran que los estudiantes de mayor conocimiento formulan más preguntas destinadas a construir un modelo científico del funcionamiento de los dispositivos. Los resultados se replican de forma consistente.