Perception of photovoltaic energy consumption in the Spanish primary sector. An environmentally profitable alternative.

Agriculture and livestock farming are activities that depend on energy consumption. Photovoltaic self-consumption systems can reduce the production costs of these actors, especially in periods of high-energy price volatility. This work aimed to determine the degree of implementation of photovoltaic self-consumption systems, their relationship with the economic impact of the energy crisis, and the perception of producers to use renewable energy sources in the Spanish agricultural system as it is one of the most important at European level. For this purpose, a survey of the Spanish agricultural and livestock system, involving 396 primary producers, was carried out between December 2022 and March 2023. The results suggest that self-consumption systems are in place in 49.1% of all farms and that these have had a positive effect in alleviating the rising energy costs suffered by the Spanish primary sector. In summary, Spanish primary producers generally have a favorable perception of the use of renewable energies on their farms, especially photovoltaic. However, the cluster analysis shows the fact that there are two types of producers, active and passive, from an environmental point of view. The characterization of this type of producers can help the Spanish Administration to improve the efficiency of its energy strategy, and can be a source of inspiration for the governments of other countries.

Valor diagnóstico del índice de masa corporal en comparación con impedancia bioeléctrica para identificar sobrepeso u obesidad en jóvenes adultos mexicanos / Diagnostic value of body mass index versus bioelectrical impedance analysisfor detection of overweight and obesity among Mexican young adults

Introducción: El índice de masa corporal (IMC) es am-pliamente utilizado para diagnosticar estado de nutrición;pero tiene limitaciones porque no evalúa la grasa corporal. Objetivo: Determinar el valor diagnóstico del IMC en com-paración con impedancia bioeléctrica para identificar sobre-peso y obesidad (SpyOb) en adultos jóvenes mexicanos.Material y métodos: Estudio de validación en adultos jó-venes mexicanos. Se midió talla con estadímetro SECA 215,peso y composición corporal con InBody 270 por personal en-trenado. Se realizaron comparaciones por sexo con U deMann Whitney y Chi2; y correlaciones de Spearman para IMCy porcentaje de grasa corporal total (%GCT). Se calculó sen-sibilidad (s) y especificidad (e) con curvas ROC comparandoIMC y %GCT para diagnosticar SpyOb. Análisis se realizó conStata 14 y valores p<0.05 fueron considerados significativos. Resultados: Se evaluaron 351 universitarios con medianade edad de 19 años. El 42.4% fue diagnosticado con SpyObde acuerdo al IMC, y 48.1% fue identificado en esa mismacondición mediante %GCT; con diferencias significativas porsexo sólo en el diagnóstico por %GCT. La correlación entre IMC y %GCT fue alta para la muestra en general (r=0.68) ymuy alta por sexo (r=0.85 hombres y r=0.81 mujeres). ElAUC para diagnosticar obesidad en mujeres fue de 0.90, conalta sensibilidad (100%) y alta especificidad (80.4%), y paradiagnosticar sobrepeso el AUC fue de 0.52 con baja sensibili-dad (31.5%) y especificidad regular (73.1%). El AUC paradiagnosticar obesidad en hombres fue de 0.84, con alta sen-sibilidad (80%) y alta especificidad (88.9%), y para diagnos-ticar sobrepeso el AUC fue de 0.63, con baja sensibilidad(32.5%) y alta especificidad (94.3%).Conclusiones: Se encontró alta y muy alta correlaciónentre IMC y %GCT, tanto en hombres como en mujeres. ElIMC es un indicador útil y confiable para diagnosticar obesi-dad, pero no para diagnosticar sobrepeso en jóvenes adultos mexicanos.(AU)

Background:The Body Mass Index (BMI) is widely usedfor nutritional status assessment; nevertheless, it has limita-tions due to the fact that it doesn’t evaluate the body fat.Objective: Identify the diagnostic value of the BMI versusBioelectrical Impedance to determinate overweight and obe-sity in young Mexican adults.(AU)

Positivización de la autoestima específica en el docente quirúrgico. Resultados del Curso 2CeQ Docencia Quirúrgica® / Positivization of specific self-esteem in the surgical teacher. Results of the grade 2CeQ Surgical Teaching®

Resumen Objetivo: Evidenciar la mejora en la autoestima específica docente y del conocimiento integral de los dominios cognitivos de Bloom en los participantes en el curso 2CeQ®, estimados a través del incremento y análisis comparativo en la puntuación obtenida en la Escala de Autoestima de Rosenberg (EAR) y ejercicios de evaluación pre y poscurso. Diseño, metodología o aproximación: Estudio analítico comparativo transversal, de datos correspondientes a los valores de las variables (puntuación obtenida) de dos cuestionarios (Escala de Autoestima de Rosenberg [EAR] y ejercicios de evaluación pre y poscurso) contestados por los participantes en el curso. Análisis estadístico: frecuencia relativa de ocurrencia, medidas de dispersión y prueba t (p<0.05 fue estadísticamente significativo). Resultados: Se incluyeron 21 individuos. Se observó una mejora significativa en la puntuación de la autoestima específica como docente quirúrgico según la EAR (16.3±5 [7-25] vs 20.9±5.2 [13-30]; p=0.003). En el ejercicio de evaluación, hubo una diferencia estadísticamente significativa en la puntuación pre y poscurso (38.5±14.3 [10.3-70.6] vs 72.4±17 [29.4-88.2]; p=0.006). Limitaciones del estudio o implicaciones: Serie unicéntrica, con limitado número del tamaño de la muestra, lo que impide validar los resultados. Originalidad o valor: Estudio en epistemología educativa quirúrgica nacional, único en su clase. Hallazgos o conclusión: La participación en el Curso "2CeQ Docencia Quirúrgica®" aumenta la autoestima específica para el ejercicio docente y la capacidad técnica para desarrollar el proceso de enseñanza aprendizaje, por lo cual puede coadyuvar a elevar la calidad de los programas educativos.

Abstract Objetive: To show improvement in teaching-specific self-esteem and comprehensive knowledge on Bloom's cognitive domains, among participants in 2CeQ® Course, estimated through increase and comparative analysis of pre- and post-course scores obtained from Rosenberg's Self-esteem Scale (RSS) and evaluation-tests. Design, methodology and approximation: Transversal, analytic and comparative study of pre- and post-course values from data corresponding to RSS and evaluation tests scores, answered by participants. Statistics: Occurrence relative frequency, dispersion calculations, and t test (p<0.05 statistically significant). Results: 21 individuals were included. A significant improvement in surgical-teaching self-esteem from RSS (16.3±5 [7-25] vs 20.9±5.2 [13-30]; p=0.003) and a statistically significant difference between pre- and postcourse test's scores (38.5±14.3 [10.3-70.6] vs 72.4±17 [29.4-88.2]; p=0.006 were observed). Limitations and implications of study: Unicentric series and a limited sample, avoiding the validation of results. Originality or value: Study on national surgical education epistemology, one of a kind. Findings and conclusion: Participation in "2CeQ" Course increases specific self-esteem for teaching and technical ability to develop teaching and learning process, helping to optimize the quality of educational programs.

Sustainable and circular agro-environmental practices: A review of the management of agricultural waste biomass in Spain and the Czech Republic.

Sustainable and circular production models, such as the circular economy and circular bioeconomy, have become key mechanisms to leave behind the traditional linear model of food production. Under this approach and considering the waste biomass potential available in Spain and the Czech Republic, the main objective of this study is to analyse the most relevant aspects of the generation, use and regulation of agricultural waste biomass (AWB) in both countries. For this purpose, a scientometric analysis and systematic review of published research in the Scopus database were carried out. A complementary analysis of AWB management policies and regulations was also part of the methodology. The results show that Spain has published almost twice as much research as the Czech Republic. Furthermore, 91% of the retrieved research prioritizes the characterization and estimation of the potential of more than 15 AWB types. Among the main ones are olive residues, horticultural residues and wheat straw, which are used for producing organic amendments, bioenergy and biofuels. The results confirm that the reduction and valorization of AWB is an issue that has become more important in the last 13 years, mainly due to the policies and strategies for circular economy and circular bioeconomy. With this in mind, this study provides relevant information for governments on the aspects that need to be improved to advance in the valorization of AWB. This study also provides guidance to farmers on the reduction and/or recovery alternatives that they can implement to move towards sustainable and circular agriculture.

Sustainability and circularity in fruit and vegetable production. Perceptions and practices of reduction and valorization of agricultural waste biomass in south-eastern Spain.

This study aims to conduct an exploratory and comparative analysis between Fruit and Vegetable Producer Organizations (FVPOs) and fruit and vegetable producers that are not part of these organizations (Non-FVPOs) regarding the prioritization, perception, and adoption of sustainable and circular practices. For this purpose, data was collected from both groups through an online survey. Statistical techniques for the comparison of two independent groups (chi-square test, Fisher's exact test, and Mann-Whitney U test) were used to examine the differences on a sample of 14 FVPOs and 22 Non-FVPOs from Spain. Although the results show more similarities than differences between the two groups, they highlight that FVPOs are more likely to prioritize environmental factors and implement both green manuring and biodegradable raffia as the main Agricultural Waste Biomass (AWB) reduction and/or valorization practices. In addition, the findings point to the relevance of environmental considerations and specifically to the Sustainable and Circular Production Models (SCPMs) as an alternative to the traditional fruit and vegetable production system. Theoretically, the results mainly contradict resource and first mover advantage arguments by revealing that more resourceful organizations do not necessarily possess better environmental management. This study also provides innovative information and relevant contributions for governments. It allows them to identify aspects that should be strengthened in relation to policies, regulatory frameworks, and/or strategies that promote sustainable and circular production systems for both FVPOs and Non-FVPOs. In addition, it contributes with implications, for organizations and farmers, how to improve actions and opportunities to advance the transition to SCPMs.

Effect of Repeated Plant Debris Reutilization as Organic Amendment on Greenhouse Soil Fertility.

Greenhouse agriculture typically generates large amounts of waste with plant residue (agricultural biomass) being the most abundant. This residue is generated on a seasonal basis, which complicates the external management of the material. Recently, the European Union (EU) has been implementing a policy based on sustainability through the circular economy that seeks to minimize waste generation. The effect of reusing 3.5 kg·m-2 tomato plants from the previous season as the only fertilizer versus no fertilization and inorganic fertilization in 215-day tomato cycles after transplanting was studied in this trial. The study was carried out during three seasons in greenhouse agriculture in Almeria (Spain) with the repeated use of the solarization technique. The plant debris had similar production results during two of the three seasons and fruit quality parameters were similar to inorganic fertilization. In addition, some physicochemical variables improved and the biological depressive effect of solarization was mitigated. The results suggest that the reuse of the tomato plant debris as the only fertilizer could be an alternative to conventional fertilization under the conditions tested.

The Management of Agriculture Plastic Waste in the Framework of Circular Economy. Case of the Almeria Greenhouse (Spain).

In recent decades, ecosystems have suffered diverse environmental impacts caused by anthropogenic activities, including the dumping of plastic waste. This situation has prompted the European Union to introduce a new policy based on the circular economy. In this study, the present state and future perspectives on the generation and treatment of plastic waste in the intensive agriculture of Almeria (Spain) are analyzed. This activity generates 1503.6 kg·ha-1·year-1, on average, of plastic waste with an approximate treatment cost of 0.25 €/kg. The present study shows that the volume of plastic waste from intensive agriculture in Almeria is constantly increasing (48,948.2 tons in 2020/21) and it is suggested that the current management system does not meet the needs of the sector. Although it presents great opportunities for improvement under the framework of the circular economy. Furthermore, this work reports a direct relationship between the price of the raw materials needed for the production of plastic and the volume of recycled plastics. For this reason, it would be advisable for the administration to consider the implementation of a tax rebate system for the sector and specifically when the petroleum derivatives used to manufacture plastic are less expensive, and the recycling option is not so attractive.

Sustainable Business Model in the Product-Service System: Analysis of Global Research and Associated EU Legislation.

The business fabric is trying to resolve the many transformations that have occurred in recent decades. Companies are obliged to offer new ways to meet the needs of the market. This situation has led to the creation of new business models that combine both competitiveness and sustainability. Among the most consistent strategies, the product-service system (PSS) stands out. A bibliometric analysis was carried out on 1088 documents during the period 2000-2020, to synthesize the knowledge base on PSS in a global context and analyse future trends. The results obtained have made it possible to identify the evolution of scientific production, the main drivers of this issue, the lines of research developed and their link with EU legislation and reveal some critical gaps in knowledge. The main lines of research describe different aspects of PSS: servitisation, product design, manufacturing, life cycle, circular economy, and sustainable development. This study has identified how its analysis has developed to date and what terms allow us to glimpse new approaches; hence, it is a useful tool for PSS researchers and sponsors who provide financial resources that allow new directions in this research.

Examining the Research Evolution on the Socio-Economic and Environmental Dimensions on University Social Responsibility.

Responsible higher education institutions have an impact on society and economic, environmental, and social development. These effects define the axes of the socially responsible management of the universities. The concept of university social responsibility (USR) manages these relationships to produce a positive impact on society through higher education, research, and the transfer of knowledge and technology, as well as education for sustainability. For this study, worldwide research into this subject was studied for the period 1970-2019. A bibliometric analysis of 870 articles was made, obtaining results for the scientific productivity of the journals, authors, institutions, and countries contributing to this research. The main category is business, management, and accounting. The most productive journal is the Business and Society Review, while the California Management Review is the most cited. The authors with the most articles are Stavnezer, Luo, and Lanero. The most productive institution is Wuhan University. The United States is the country with the most publications and citations, and the same country, together with the United Kingdom, make the most international contributions. Evidence shows growing worldwide interest in the economic and environmental impacts of USR. Future research should focus on analysing the links between the responsible and sustainable consumption of universities and their short-term financial, economic, and sustainable impacts.

Analysis of the Circular Economic Production Models and Their Approach in Agriculture and Agricultural Waste Biomass Management.

As of now, circular economic production models of the circular economy (CEPMs), which include circular economy, bioeconomy, and circular bioeconomy, are among the main tools characterizing development policies in different countries. During the last five years, policies and strategies regarding CEPMs have promoted and contributed to the development of research on this topic. The evolution and most relevant aspects of the three CEPMs previously mentioned have been analyzed from a sample of 2190 scientific publications obtained from the Scopus database. Bibliometric analysis has been used to evaluate the approach of these models in agriculture and to introduce the ways in which they address the management of agricultural waste biomass (AWB). Results show that the circular economy is the most studied and prioritized model in China and most European countries, with the UK leading the way. Germany leads in topics related to the bioeconomy. The management policies and strategies of the circular bioeconomy are key to promoting research focused on AWB valorization since bioenergy and/or biofuel production continue to be a priority.

Profit Analysis of Papaya Crops under Greenhouses as an Alternative to Traditional Intensive Horticulture in Southeast Spain.

The high-yield agricultural model in Almería is based on eight different crops. Having led fruit and vegetable exports in Spain for more than 50 years, a decrease in melon and watermelon growing areas in Almería caused a change in supply that affected the model's profit. Papaya cultivation could reactivate the profit of the agricultural model in Almería and also improve the available product range. The papaya crop needs greenhouse infrastructures high enough to contain the growth and size of the plants during a cycle crop, which is possible in most of the greenhouses of the Horticultural production model of Almería. The papaya harvests obtained in the region meet the quality requirements demanded by European markets. Furthermore, yields obtained are equal or higher than yields obtained by other producing countries. This crop improves profit compared with the profit obtained from the rotation of other horticultural crops that have been traditionally grown in the region.

The Production and Quality of Different Varieties of Papaya Grown under Greenhouse in Short Cycle in Continental Europe.

In Europe, papaya consumption is growing due to its nutritional properties. The proximity of consumer markets to Southeast Spain allows fruits to be harvested at a more advanced stage of maturity compared to exporting countries from outside Europe, a timeline which improves the quality of the papaya. Experiments have been carried out to assess the adaptation of papaya to protected cropping systems (under greenhouse) in the region. In this paper, we showed the results obtained in an experiment with five varieties, taking the most cultivated variety as control, which was grafted on its own female rootstock, in addition to another four new varieties that were introduced. Transplanting was made with early sex-identified plants in the nursery. Cultivation was developed in a 446-day cycle, almost 15 months and fruits were always harvested from the soil, due to the height that the plant reached in that period. The best yield parameters and fruit characteristics were obtained from hermaphrodite Intenzza papaya grafted on female papaya rootstock, although there were also other varieties which gave results that made possible its cultivation under this production system.

Aquifer Sustainability and the Use of Desalinated Seawater for Greenhouse Irrigation in the Campo de Níjar, Southeast Spain.

In the Campo de Níjar (southeast Spain), an intensive horticulture model under plastic has been developed based on the use of groundwater. For many years, aquifers have been overexploited, almost generating an environmental collapse. The construction of a desalination plant was planned to improve this situation and to achieve sustainable aquifer management. However, the aquifer is still being overexploited, since farmers scarcely use desalinated seawater for irrigation. In this paper, farmers irrigating with desalinated seawater are characterized, since they contribute to aquifer sustainability. The study aimed to identify the variables which condition the use of this water resource, as well as the kinds of incentives that encourage this option. For this purpose, a survey was undertaken within a sample of 110 farmers. A cluster analysis and a binary logistic regression were employed. The results from the cluster analysis allowed the characterization of farmers who use desalinated seawater for irrigation. Furthermore, the regression model showed the variables that determine a more intensive use of this irrigation source, such as crop diversification, availability of different water resources and the conductivity of aquifer water available for irrigation. The incentives promoting the use of desalinated seawater for irrigation that most encourage farmers are the implementation of tax relief, price reductions and the obligation to install rainwater collection systems.

System to Detect Racial-Based Bullying through Gamification.

Prevention and detection of bullying due to racial stigma was studied in school contexts using a system designed following "gamification" principles and integrating less usual elements, such as social interaction, augmented reality and cell phones in educational scenarios. "Grounded Theory" and "User Centered Design" were employed to explore coexistence inside and outside the classroom in terms of preferences and distrust in several areas of action and social frameworks of activity, and to direct the development of a cell phone app for early detection of school bullying scenarios. One hundred and fifty-one interviews were given at five schools selected for their high multiracial percentage and conflict. The most outstanding results were structural, that is the distribution of the classroom group by type of activity and subject being dealt with. Furthermore, in groups over 12 years of age, the relational structures in the classroom in the digital settings in which they participated with their cell phones did not reoccur, because face-to-face and virtual interaction between students with the supervision and involvement of the teacher combined to detect bullying caused by racial discrimination.

Instructional Changes Adopted for an Engineering Course: Cluster Analysis on Academic Failure.

As first year students come from diverse backgrounds, basic skills should be accessible to everyone as soon as possible. Transferring such skills to these students is challenging, especially in highly technical courses. Ensuring that essential knowledge is acquired quickly promotes the student's self-esteem and may positively influence failure rates. Metaphors can help do this. Metaphors are used to understand the unknown. This paper shows how we made a turn in student learning at the University of Almeria. Our hypothesis assumed that metaphors accelerate the acquisition of basic knowledge so that other skills built on that foundation are easily learned. With these goals in mind, we changed the way we teach by using metaphors and abstract concepts in a computer organization course, a technical course in the first year of an information technology engineering degree. Cluster analysis of the data on collective student performance after this methodological change clearly identified two distinct groups. These two groups perfectly matched the "before and after" scenarios of the use of metaphors. The study was conducted during 11 academic years (2002/2003 to 2012/2013). The 475 observations made during this period illustrate the usefulness of this change in teaching and learning, shifting from a propositional teaching/learning model to a more dynamic model based on metaphors and abstractions. Data covering the whole period showed favorable evolution of student achievement and reduced failure rates, not only in this course, but also in many of the following more advanced courses. The paper is structured in five sections. The first gives an introduction, the second describes the methodology. The third section describes the sample and the study carried out. The fourth section presents the results and, finally, the fifth section discusses the main conclusions.

Heterogeneity of the environmental regulation of industrial wastewater: European wineries.

The European legislation of the pollution of industrial wastewater shows a high degree of heterogeneity. This fact implies that there is a market failure with relevant consequences. Within the European Union, each Member State performs a specific transposition of the Water Framework Directive 2000/60. The member states introduce different sanitation fees to correct water pollution. In this paper, the case of the European wine industry is analyzed. It studies the sanitation fees of the five major wine producing countries: France, Italy, Spain, Germany and Portugal. Results show significant differences among the wastewater fees and the study reveals how such heterogeneity leads to relevant market distortions. The research concludes that more homogeneous environmental regulation would promote more sustainable wine production processes with more efficient water management and purification systems, as well as the introduction of cutting edge technologies.

Molecular chaperone Hsp90 is a therapeutic target for noroviruses.

UNLABELLED: Human noroviruses (HuNoV) are a significant cause of acute gastroenteritis in the developed world, and yet our understanding of the molecular pathways involved in norovirus replication and pathogenesis has been limited by the inability to efficiently culture these viruses in the laboratory. Using the murine norovirus (MNV) model, we have recently identified a network of host factors that interact with the 5' and 3' extremities of the norovirus RNA genome. In addition to a number of well-known cellular RNA binding proteins, the molecular chaperone Hsp90 was identified as a component of the ribonucleoprotein complex. Here, we show that the inhibition of Hsp90 activity negatively impacts norovirus replication in cell culture. Small-molecule-mediated inhibition of Hsp90 activity using 17-DMAG (17-dimethylaminoethylamino-17-demethoxygeldanamycin) revealed that Hsp90 plays a pleiotropic role in the norovirus life cycle but that the stability of the viral capsid protein is integrally linked to Hsp90 activity. Furthermore, we demonstrate that both the MNV-1 and the HuNoV capsid proteins require Hsp90 activity for their stability and that targeting Hsp90 in vivo can significantly reduce virus replication. In summary, we demonstrate that targeting cellular proteostasis can inhibit norovirus replication, identifying a potential novel therapeutic target for the treatment of norovirus infections. IMPORTANCE: HuNoV are a major cause of acute gastroenteritis around the world. RNA viruses, including noroviruses, rely heavily on host cell proteins and pathways for all aspects of their life cycle. Here, we identify one such protein, the molecular chaperone Hsp90, as an important factor required during the norovirus life cycle. We demonstrate that both murine and human noroviruses require the activity of Hsp90 for the stability of their capsid proteins. Furthermore, we demonstrate that targeting Hsp90 activity in vivo using small molecule inhibitors also reduces infectious virus production. Given the considerable interest in the development of Hsp90 inhibitors for use in cancer therapeutics, we identify here a new target that could be explored for the development of antiviral strategies to control norovirus outbreaks and treat chronic norovirus infection in immunosuppressed patients.

Norovirus genome circularization and efficient replication are facilitated by binding of PCBP2 and hnRNP A1.

Sequences and structures within the terminal genomic regions of plus-strand RNA viruses are targets for the binding of host proteins that modulate functions such as translation, RNA replication, and encapsidation. Using murine norovirus 1 (MNV-1), we describe the presence of long-range RNA-RNA interactions that were stabilized by cellular proteins. The proteins potentially responsible for the stabilization were selected based on their ability to bind the MNV-1 genome and/or having been reported to be involved in the stabilization of RNA-RNA interactions. Cell extracts were preincubated with antibodies against the selected proteins and used for coprecipitation reactions. Extracts treated with antibodies to poly(C) binding protein 2 (PCBP2) and heterogeneous nuclear ribonucleoprotein (hnRNP) A1 significantly reduced the 5'-3' interaction. Both PCBP2 and hnRNP A1 recombinant proteins stabilized the 5'-3' interactions and formed ribonucleoprotein complexes with the 5' and 3' ends of the MNV-1 genomic RNA. Mutations within the 3' complementary sequences (CS) that disrupt the 5'-3'-end interactions resulted in a significant reduction of the viral titer, suggesting that the integrity of the 3'-end sequence and/or the lack of complementarity with the 5' end is important for efficient virus replication. Small interfering RNA-mediated knockdown of PCBP2 or hnRNP A1 resulted in a reduction in virus yield, confirming a role for the observed interactions in efficient viral replication. PCBP2 and hnRNP A1 induced the circularization of MNV-1 RNA, as revealed by electron microscopy. This study provides evidence that PCBP2 and hnRNP A1 bind to the 5' and 3' ends of the MNV-1 viral RNA and contribute to RNA circularization, playing a role in the virus life cycle.

Identification of RNA-protein interaction networks involved in the norovirus life cycle.

Human noroviruses are one of the major causes of acute gastroenteritis in the developed world, yet our understanding of their molecular mechanisms of genome translation and replication lags behind that for many RNA viruses. Due to the nonculturable nature of human noroviruses, many related members of the Caliciviridae family of small RNA viruses are often used as model systems to dissect the finer details of the norovirus life cycle. Murine norovirus (MNV) has provided one such system with which to study the basic mechanisms of norovirus translation and replication in cell culture. In this report we describe the use of riboproteomics to identify host factors that interact with the extremities of the MNV genome. This network of RNA-protein interactions contains many well-characterized host factors, including PTB, La, and DDX3, which have been shown to play a role in the life cycle of other RNA viruses. By using RNA coimmunoprecipitation, we confirmed that a number of the factors identified using riboproteomics are associated with the viral RNA during virus replication in cell culture. We further demonstrated that RNA inhibition-mediated knockdown of the intracellular levels of a number of these factors inhibits or slows norovirus replication in cell culture, allowing identification of new intracellular targets for this important group of pathogens.

Reverse genetics mediated recovery of infectious murine norovirus.

Human noroviruses are responsible for most cases of human gastroenteritis (GE) worldwide and are recurrent problem in environments where close person-to-person contact cannot be avoided (1, 2). During the last few years an increase in the incidence of outbreaks in hospitals has been reported, causing significant disruptions to their operational capacity as well as large economic losses. The identification of new antiviral approaches has been limited due to the inability of human noroviruses to complete a productive infection in cell culture (3). The recent isolation of a murine norovirus (MNV), closely related to human norovirus (4) but which can be propagated in cells (5) has opened new avenues for the investigation of these pathogens (6, 7). MNV replication results in the synthesis of new positive sense genomic and subgenomic RNA molecules, the latter of which corresponds to the last third of the viral genome (Figure 1). MNV contains four different open reading frames (ORFs), of which ORF1 occupies most of the genome and encodes seven non-structural proteins (NS1-7) released from a polyprotein precursor. ORF2 and ORF3 are contained within the subgenomic RNA region and encode the capsid proteins (VP1 and VP2, respectively) (Figure 1). Recently, we have identified that additional ORF4 overlapping ORF2 but in a different reading frame is functional and encodes for a mitochondrial localised virulence factor (VF1) (8). Replication for positive sense RNA viruses, including noroviruses, takes place in the cytoplasm resulting in the synthesis of new uncapped RNA genomes. To promote viral translation, viruses exploit different strategies aimed at recruiting the cellular protein synthesis machinery (9-11). Interestingly, norovirus translation is driven by the multifunctional viral protein-primer VPg covalently linked to the 5' end of both genomic and subgenomic RNAs (12-14). This sophisticated mechanism of translation is likely to be a major factor in the limited efficiency of viral recovery by conventional reverse genetics approaches. Here we report two different strategies based on the generation of murine norovirus-1 (referred to as MNV herewith) transcripts capped at the 5' end. One of the methods involves both in vitro synthesis and capping of viral RNA, whereas the second approach entails the transcription of MNV cDNA in cells expressing T7 RNA polymerase. The availability of these reverse genetics systems for the study of MNV and a small animal model has provided an unprecedented ability to dissect the role of viral sequences in replication and pathogenesis (15-17).