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Community-acquired pneumonia represents the third-highest cause of mortality in industrialized countries and the first due to infection. Although guidelines for the approach to this infection model are widely implemented in international health schemes, information continually emerges that generates controversy or requires updating its management. This paper reviews the most important issues in the approach to this process, such as an aetiologic update using new molecular platforms or imaging techniques, including the diagnostic stewardship in different clinical settings. It also reviews both the Intensive Care Unit admission criteria and those of clinical stability to discharge. An update in antibiotic, in oxygen, or steroidal therapy is presented. It also analyzes the management out-of-hospital in CAP requiring hospitalization, the main factors for readmission, and an approach to therapeutic failure or rescue. Finally, the main strategies for prevention and vaccination in both immunocompetent and immunocompromised hosts are reviewed. [ABSTRACT FROM AUTHOR]

Nosocomial pneumonia, or hospital-acquired pneumonia (HAP), and ventilator-associated pneumonia (VAP) are important health problems worldwide, with both being associated with substantial morbidity and mortality. HAP is currently the main cause of death from nosocomial infection in critically ill patients. Although guidelines for the approach to this infection model are widely implemented in international health systems and clinical teams, information continually emerges that generates debate or requires updating in its management. This scientific manuscript, written by a multidisciplinary team of specialists, reviews the most important issues in the approach to this important infectious respiratory syndrome, and it updates various topics, such as a renewed etiological perspective for updating the use of new molecular platforms or imaging techniques, including the microbiological diagnostic stewardship in different clinical settings and using appropriate rapid techniques on invasive respiratory specimens. It also reviews both Intensive Care Unit admission criteria and those of clinical stability to discharge, as well as those of therapeutic failure and rescue treatment options. An update on antibiotic therapy in the context of bacterial multiresistance, in aerosol inhaled treatment options, oxygen therapy, or ventilatory support, is presented. It also analyzes the out-of-hospital management of nosocomial pneumonia requiring complete antibiotic therapy externally on an outpatient basis, as well as the main factors for readmission and an approach to management in the emergency department. Finally, the main strategies for prevention and prophylactic measures, many of them still controversial, on fragile and vulnerable hosts are reviewed. [ABSTRACT FROM AUTHOR]

Cyberattacks capitalize on human behaviors. The prevalence of cyberattacks surged during the COVID-19 pandemic, fueled by the increased interconnectivity of individuals on online platforms and shifts in their psychological dynamics due to the pandemic's context. The enhancement of human factors becomes imperative in formulating a robust cybersecurity strategy against social engineering in the post-COVID-19 era and in anticipation of analogous pandemics. This study aims to propose a model for delineating strategies across various phases of cyberattacks, grounded in the cyber kill chain model, while also encompassing cognitive mechanisms for adaptive responses. This approach aims to cultivate defensive cognitive factors like resilience and self-efficacy. To achieve this objective, we conducted an exploratory study adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Subsequently, we pursued a descriptive and correlational study based on prevalent attacks during the pandemic. The intention was to pinpoint proactive factors conducive to the development of cognitive capabilities to counter cyberattacks. These insights could pave the way for the creation of training programs and technological solutions aimed at mitigating the impact of such cyberattacks. [ABSTRACT FROM AUTHOR]

Water scarcity is one of the greatest concerns for agronomy worldwide. In recent years, many water resources have been depleted due to multiple factors, especially mismanagement. Water resource shortages lead to cropland expansion, which likely influences climate change and affects global agriculture, especially horticultural crops. Fruit yield is the final aim in commercial orchards; however, drought can slow tree growth and/or decrease fruit yield and quality. It is therefore necessary to find approaches to solve this problem. The main objective of this review is to discuss the most recent horticultural, biochemical, and molecular strategies adopted to improve the response of temperate fruit crops to water stress. We also address the viability of cultivating fruit trees in dry areas and provide precise protection methods for planting fruit trees in arid lands. We review the main factors involved in planting fruit trees in dry areas, including plant material selection, regulated deficit irrigation (DI) strategies, rainwater harvesting (RWH), and anti-water stress materials. We also provide a detailed analysis of the molecular strategies developed to combat drought, such as Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) through gene overexpression or gene silencing. Finally, we look at the molecular mechanisms associated with the contribution of the microbiome to improving plant responses to drought. [ABSTRACT FROM AUTHOR]

This study aimed at the monitoring of the apricot (Prunus armeniaca L.) ripening progression through the expression analysis of 25 genes related to fruit quality traits in nine cultivars with great differences in fruit color and ripening date. The level of pigment compounds, such as anthocyanins and carotenoids, is a key factor in food taste, and is responsible for the reddish blush color or orange skin and flesh color in apricot fruit, which are desirable quality traits in apricot breeding programs. The construction of multiple linear regression models to predict anthocyanins and carotenoids content from gene expression allows us to evaluate which genes have the strongest influence over fruit color, as these candidate genes are key during biosynthetic pathways or gene expression regulation, and are responsible for the final fruit phenotype. We propose the gene CHS as the main predictor for anthocyanins content, CCD4 and ZDS for carotenoids content, and LOX2 and MADS-box for the beginning and end of the ripening process in apricot fruit. All these genes could be applied as RNA markers to monitoring the ripening stage and estimate the anthocyanins and carotenoids content in apricot fruit during the ripening process. [ABSTRACT FROM AUTHOR]

Technical drawing (TD) is a subject frequently perceived by engineering students as difficult and even lacking in practical application. Different studies have shown that there is a relationship between studying TD and improvement of spatial ability, and there are precedents of works describing successful educational methodologies based on information and communications technology (ICT), dedicated in some cases to improving spatial ability, and in other cases to facilitating the teaching of TD. Furthermore, interdisciplinary learning (IL) has proven to be effective for the training of science and engineering students. Based on these facts, this paper presents a novel IL educational methodology that, using ICT-based tools, links the teaching of industrial radiology with the teaching of TD, enhancing the spatial ability of students. First, the process of creating the didactic material is described in summary form, and thereafter, the way in which this educational methodology is implemented in the classroom. Finally, we analyze how the use of ICT-based didactic tools such as the one described in this paper can contribute to the achievement of the sustainable development goals set out in the 2030 Agenda of the United Nations. [ABSTRACT FROM AUTHOR]

Featured Application: The process of technological obsolescence suffered by the virtual reality learning environments used in higher education and its consequences in educational fields are analyzed in this paper. The concept of technological obsolescence that affects computer programs is a readily observable phenomenon that has been widely studied over the past half century. The so-called virtual reality learning environments (VRLEs) which are used to support university classes are significantly affected by this technological obsolescence, decreasing their formative effectiveness as the obsolescence process advances. In this study, the technological obsolescence of two VRLEs is analyzed by means of an empirical research based on survey results (N = 135) after using the VRLEs in engineering classes. Several key performance indicators (KPIs) were analyzed during seven academic courses, including motivation, interactivity, ease of use and usefulness. Since both VRLEs were updated during this research work, the influence of these improvements is discussed in detail from a technological obsolescence point of view. Results suggest that the technological obsolescence negatively affects the students' opinion regarding motivation and interactivity, but the other KPIs (ease of use and usefulness) are hardly affected. In contrast, results indicate that the technological obsolescence can be reversed if periodic updates of educational tools are carried out using modern development software. [ABSTRACT FROM AUTHOR]

Featured Application: The key characteristics that a virtual reality learning environment (VRLE) must have to support an appropriate level of meaningful learning in higher education are detailed in this paper. The increasing dissemination of virtual reality learning environments (VRLEs) compels the elucidation of how these didactic tools can improve their effectiveness at the formative level. The motivation generated in students by a VRLE is revealed as a key factor in achieving meaningful learning, but such a motivation by itself alone does not guarantee the long-term retention of knowledge. To identify the necessary characteristics of a VRLE to achieve an appropriate level of meaningful learning, this paper compares a set of VRLEs created in previous years with a group of recently developed VRLEs, after being used by engineering students. A description of the design process of the both VRLEs groups is included in this paper. Most significantly, analysis of the response of a total of 103 students in a specific survey reveals how a step-by-step protocol system helped improve students' knowledge and retention after one year of using a VRLE. Thus, this study not only demonstrates the importance of using modern development engines when creating or updating a VRLE to achieve student motivation, but also justifies in many cases the use of a step-by-step protocol as a method to improve the long-term retention of knowledge. [ABSTRACT FROM AUTHOR]

β-Glucosidase (EC 3.2.1.21) is a prominent member of the GH1 family of glycoside hydrolases. The properties of this β-glucosidase appear to include resistance to temperature, urea, and iodoacetamide, and it is activated by 2-ME, similar to other members. β-Glucosidase from chayote (Sechium edule) was purified by ionic-interchange chromatography and molecular exclusion chromatography. Peptides detected by LC-ESI-MS/MS were compared with other β-glucosidases using the BLAST program. This enzyme is a 116 kDa protein composed of two sub-units of 58 kDa and shows homology with Cucumis sativus β-glucosidase (NCBI reference sequence XP_004154617.1), in which seven peptides were found with relative masses ranging from 874.3643 to 1587.8297. The stability of β-glucosidase depends on an initial concentration of 0.2 mg/mL of protein at pH 5.0 which decreases by 33% in a period of 30 h, and then stabilizes and is active for the next 5 days (pH 4.0 gives similar results). One hundred μg/mL β-D-glucose inhibited β-glucosidase activity by more than 50%. The enzyme had a Km of 4.88 mM with p-NPG and a Kcat of 10,000 min−1. The optimal conditions for the enzyme require a pH of 4.0 and a temperature of 50 °C. [ABSTRACT FROM AUTHOR]

Fluoride is naturally present in the earth's crust and can be found in rocks, coal, and clay; thus, it can be found in small quantities in water, air, plants, and animals. Therefore, humans are exposed to fluoride through food, drinking water, and in the air they breathe. fluoride is essential to maintain bone strength and to protect against dental decay, but if it is absorbed too frequently, it can cause tooth decay, osteoporosis, and damage to kidneys, bones, nerves, and muscles. Therefore, the present work was aimed at determining the effect of intake of sodium fluoride (NaF) as an apoptosis inducer in leukocytes of rats treated for eight weeks with 1 or 50 parts per million (ppm) NaF. Expression of p53, bcl-2, and caspade-3 were used as apoptotic and general metabolism indicators of leukocyte-like indicators of the (INT) oxidation system. Male rats were exposed to NaF (1 and 500 ppm) for eight weeks, and then sacrificed weekly to obtain blood samples. Expression of p53, bcl-2, and caspase-3 were determined in leukocytes by Western blot, and general metabolism of leukocytes was analyzed with a commercial kit. We found changes in the expression of the proteins described, especially when the animals received 50 ppm of NaF. These results indicate that NaF intoxication can be an apoptosis inducer in rat leukocytes treated with the compound for eight weeks. [ABSTRACT FROM AUTHOR]

Fluoride intoxication has been shown to produce diverse deleterious metabolic alterations within the cell. To determine the effects of sodium fluoride (NaF) treatment on malondialdehyde (MDA) levels and on the activity of antioxidant enzymes in rat erythrocytes, Male Wistar rats were treated with 50 ppm of NaF or were untreated as controls. Erythrocytes were obtained from rats sacrificed weekly for up to eight weeks and the concentration of MDA in erythrocyte membrane was determined. In addition, the activity of the enzymes superoxide, dismutase, catalase, and glutathione peroxidase were determined. Treatment with NaF produces an increase in the concentration of malondialdehyde in the erythrocyte membrane only after the eight weeks of treatment. On the other hand, antioxidant enzyme activity was observed to increase after the fourth week of NaF treatment. In conclusion, intake of NaF produces alterations in the erythrocyte of the male rat, which indicates induction of oxidative stress. [ABSTRACT FROM AUTHOR]

Presently, several jobs require the collaboration of humans and machines to perform different services and tasks. The ease and intuitiveness of the worker when using each machine will not only improve the worker's experience but also improve the company's productivity and the satisfaction that all users have. Specifically, electromechanical devices used to provide cleaning services require complex interactions. These interactions determine the usability and performance of devices. Therefore, devices must have appropriate ergonomic arrangements for human–machine interactions. Otherwise, the desired performance cannot be achieved. This study analyzes the performance of an urban cleaning device (pressure washer on a power take-off van) using human–machine interaction method. The method measures visceral and behavioral levels (set by Norman) and service times. Using these measurements, the usability of the pressure washer is determined according to different factors that facilitate the operator's well-being in the working environment. A pressure washer from Feniks Cleaning and Safety, Limited Company, has been studied. Sixteen errors related to ergonomics, usability and safety were identified in this machine, which operates in more than 40 locations in Spain. Therefore, this study provides valuable information on the usability and performance of pressure washers, as well as possibilities for improvement. [ABSTRACT FROM AUTHOR]

Microfluidics has proven to be an extraordinary working platform to mimic and study blood flow phenomena and the dynamics of components of the human microcirculatory system. However, the use of real blood increases the complexity to perform these kinds of in vitro blood experiments due to diverse problems such as coagulation, sample storage, and handling problems. For this reason, interest in the development of fluids with rheological properties similar to those of real blood has grown over the last years. The inclusion of microparticles in blood analogue fluids is essential to reproduce multiphase effects taking place in a microcirculatory system, such as the cell-free layer (CFL) and Fähraeus–Lindqvist effect. In this review, we summarize the progress made in the last twenty years. Size, shape, mechanical properties, and even biological functionalities of microparticles produced/used to mimic red blood cells (RBCs) are critically exposed and analyzed. The methods developed to fabricate these RBC templates are also shown. The dynamic flow/rheology of blood particulate analogue fluids proposed in the literature (with different particle concentrations, in most of the cases, relatively low) is shown and discussed in-depth. Although there have been many advances, the development of a reliable blood particulate analogue fluid, with around 45% by volume of microparticles, continues to be a big challenge. [ABSTRACT FROM AUTHOR]

No natural sources of resistance to Plum pox virus (PPV, sharka disease) have been identified in peach. However, previous studies have demonstrated that grafting a "Garrigues" almond scion onto "GF305" peach rootstock seedlings heavily infected with PPV can progressively reduce disease symptoms and virus accumulation. Furthermore, grafting a "Garrigues" scion onto the "GF305" rootstock has been shown to completely prevent virus infection. This study aims to analyse the rewiring of gene expression associated with this resistance to PPV transmitted by grafting through the phloem using RNA-Seq and RT-qPCR analysis. A total of 18 candidate genes were differentially expressed after grafting "Garrigues" almond onto healthy "GF305" peach. Among the up-regulated genes, a HEN1 homolog stands out, which, together with the differential expression of RDR- and DCL2-homologs, suggests that the RNA silencing machinery is activated by PPV infection and can contribute to the resistance induced by "Garrigues" almond. Glucan endo-1,3-beta D-glucosidase could be also relevant for the "Garrigues"-induced response, since its expression is much higher in "Garrigues" than in "GF305". We also discuss the potential relevance of the following in PPV infection and "Garrigues"-induced resistance: several pathogenesis-related proteins; no apical meristem proteins; the transcription initiation factor, TFIIB; the speckle-type POZ protein; in addition to a number of proteins involved in phytohormone signalling. [ABSTRACT FROM AUTHOR]

Long polymeric chains highly stretched and aligned with the flow confer a strong mechanical anisotropy on a viscoelastic solution. The electrically-driven transport of free ions under such conditions is far from being understood. In this paper, we determine experimentally whether the above-mentioned deviation from isotropy affects the electric charge transport across the liquid. To this end, we measure the electrical conductivity in the flow (stretching) direction of the cylindrical liquid filament formed in the elasto-capillary thinning that arises during the breakup of a viscoelastic liquid bridge. First, we examine the behavior of monodisperse solutions of polyethylene oxide (PEO) in a mixture of glycerine and water. For all the concentrations and molecular weights considered, the filament conductivity remains practically the same as the isotropic conductivity measured under hydrostatic conditions. However, we observe a decrease in the electric current at the end of elasto-capillary regime which may partially be attributed to the reduction of the liquid conductivity. Then, we measure the conductivity of bidisperse solutions of PEO with very different molecular weights. In this case, a significant decrease in conductivity is observed as the filament radius decreases. This constitutes the first experimental evidence of ion mobility reduction in stretching viscoelastic filaments, a relevant effect in applications such as electrospinning. [ABSTRACT FROM AUTHOR]

Peach (Prunus persica (L.) Batsch) is one of the most produced and studied stone fruits. Many genetic and genomic resources are available for this species, including a high-quality genome. More recently, a new high-density Illumina peach Single Nucleotide Polymorphism (SNP) chip (9+9K) has been developed by an international consortium as an add-on to the previous 9K array. In the current study, this new array was used to study the genetic diversity and population structure of the National Peach Germplasm Collection of the Agrifood Research and Technology Centre of Aragon (CITA), located in Zaragoza (northern Spain). To accomplish this, 90 peach accessions were genotyped using the new peach SNP chip (9+9K). A total of 9796 SNPs were finally selected for genetic analyses. Through Identity-By-Descent (IBD) estimate analysis, 15 different groups with genetically identical individuals were identified. The genetic diversity and population structure elucidated a possible exchange of germplasm material among regions, mainly in the northern regions of Spain. This study will allow for more efficient management of the National Peach Germplasm Collection by classifying valuable individuals for genetic diversity preservation and will benefit forthcoming Genome-Wide Association Studies (GWAS) of commercially important fruit traits in peach. [ABSTRACT FROM AUTHOR]

Throughout history, new strategies and technologies have played a key role in promoting the development of agriculture. New strategies have led to substantial improvements in crop productivity and fruit quality. The cultivation of peach and apricot in controlled greenhouse conditions is one such strategy. The aim of the protected cultivation of these species in greenhouses is to grow fruit trees by modifying the natural environment of the tree, including the harvest duration, which can be extended. This protected cultivation should improve yield, thus increasing the benefit–cost ratio, especially in the case of organic production. Here we review the main factors involved in greenhouse fruit tree cultivation, including the planting systems and substrate, cultivar and rootstock selection, pollination management, orchard management, and environmental management. Greenhouse cultivation makes it possible to control environmental conditions like wind speed, moisture, temperature, mineral nutrients, light intensity, and the atmospheric composition, and thus gives us a better understanding of growth factor requirements, and the means to improve fruit productivity. A protected environment has been shown to be effective in maintaining a relatively high temperature and preventing leaf injury due to environmental factors, resulting in a longer period of photosynthetic activity, which increases the photosynthetic production, and is therefore a suitable alternative strategy for production in cold regions. The main benefits of apricot and peach cultivation in greenhouses are: (1) precocity; (2) high fruit quality, storage life, and market proximity; and (3) good plant health, suitable for organic cultivation. However, the main limiting factors for fruit tree production in greenhouse conditions to take into account are: (1) light scarcity at high latitudes; (2) a lack of cold for bud breaking, flowering, and fruit production; (3) potentially excessive temperatures in warm regions, which reduce the photosynthesis rate; and (4) a reduction of fruit quality, coloring, and aroma compounds in certain warm conditions with light day/night temperature variations. [ABSTRACT FROM AUTHOR]

In plants, fruit ripening is a coordinated developmental process that requires the change in expression of hundreds to thousands of genes to modify many biochemical and physiological signal cascades such as carbohydrate and organic acid metabolism, cell wall restructuring, ethylene production, stress response, and organoleptic compound formation. In Prunus species (including peaches, apricots, plums, and cherries), fruit ripening leads to the breakdown of complex carbohydrates into sugars, fruit firmness reductions (softening by cell wall degradation and cuticle properties alteration), color changes (loss of green color by chlorophylls degradation and increase in non-photosynthetic pigments like anthocyanins and carotenoids), acidity decreases, and aroma increases (the production and release of organic volatile compounds). Actually, the level of information of molecular events at the transcriptional, biochemical, hormonal, and metabolite levels underlying ripening in Prunus fruits has increased considerably. However, we still poorly understand the molecular switch that occurs during the transition from unripe to ripe fruits. The objective of this review was to analyze of the molecular bases of fruit quality in Prunus species through an integrated metabolic, genomic, transcriptomic, and epigenetic approach to better understand the molecular switch involved in the ripening process with important consequences from a breeding point of view. [ABSTRACT FROM AUTHOR]

Prunus species are important crops in temperate regions. In these regions, drought periods are predicted to occur more frequently due to climate change. In this sense, to reduce the impact of climate warming, obtaining new tolerant/resistant cultivars and rootstocks is a mandatory goal in Prunus breeding. Therefore, the current study assembled three Prunus species including almond, (P. dulcis Mill D.A. Webb), apricot (P. armeniaca L.) and peach (P. persica L.) to model the temporal effects of drought. A hybrid peach × almond and a wild almond-relative species Prunus webbii were also included in the study. Physiological traits associated with photosynthetic activity, leaf water status, and chlorophyll content were assessed under three watering treatments. Results showed that effects of time, genotype, and treatment interact significantly in all traits. In addition, results confirmed that P. webbii have a greater tolerance to drought than commercial rootstocks. However, "Real Fino" apricot showed the fastest recovery after re-irrigation while being one of the most affected cultivars. In addition, from the better response to these watering treatments by the almond genotypes, two different trends were observed after re-irrigation treatment that clearly differentiate the response of the almond cultivar "Garrigue" from the rest of Prunus genotypes. A better characterization of the short-term drought response in Prunus, an accurate and more efficient evaluation of the genotype effect was obtained from the use of mixed models considering appropriate variance–covariance structures. Although the advantages of these approaches are rarely used in Prunus breeding, these methodologies should be undertaken in the future by breeders to increase efficiency in developing new breeding materials. [ABSTRACT FROM AUTHOR]

Nowadays, there are many situations in which information and communications technology (ICT) is used as a vehicle to transmit knowledge. The fast evolution of technology in recent decades has favored the development of virtual reality (VR) and augmented reality (AR) and with them the emergence of virtual laboratories (VLs) using VR or AR. Since such technologies can help students understand the atomic spatial distribution, crystallography is a discipline that has taken advantage of the use of VL in the teaching of crystal lattices, thus solving the usual educational problem of visualization in two- and three-dimensions. This paper presents a literature review that helps to identify the main features of VLs (based on VR or AR) that have been developed in the academic field to support the learning of crystallography concepts. Furthermore, this paper describes a VL developed by the authors where students can learn the main contents related to the 14 Bravais lattices (unit cells, directions, crystallographic planes, interstitial sites, etc.) by exploring the stands of a virtual museum. Such a VL uses non-immersive VR and has been designed based on the authors' long-term research to achieve a high learning effectiveness educative platform. [ABSTRACT FROM AUTHOR]

We study with ultra-high-speed imaging the thinning of the filament formed during the breakup of a pendant droplet of very weakly viscoelastic polymer solutions of polyvinylpyrrolidone (PVP) and polyethylene oxide (PEO). In the latter case, we consider two molecular weights: 10 5 g/mol (PEO100K) and 2 × 10 6 g/mol (PEO2M). The results allow us to measure with high reproducibility extensional relaxation times of the order of 10 μ s. Despite the noticeable differences between PVP and PEO100K, very similar values are obtained for the range of concentrations where the linear elasto-capillary is established. For PEO2M, the extensional relaxation time depends on the concentration even for values significantly smaller than the overlap one. The prediction c low for the concentration below which the linear elasto-capillary regime cannot be reached qualitatively agrees with the results for PVP and PEO2M, while it underestimates the critical concentration for PEO100K. The results for PEO2M are consistent with those reported in the literature for higher concentrations. [ABSTRACT FROM AUTHOR]

Despite the interesting applications that the PDF-3D offers in teaching, especially for subjects related to spatial comprehension difficulties, such a didactic tool is not well known in the education sector. Thus, a proposal of using PDF-3D in engineering studies is presented in this paper, specifically, in the field of teaching ternary phase diagrams (TPDs). The didactic resource—easy to design and easy to use—allows students to overcome spatial visualization difficulties linked with TPDs. According to students' opinions, the PDF-3D is an effective tool to use in any topic related to spatial difficulties and, in addition, is a friendly and easy-to-use tool. This fact and the simplicity of designing a PDF-3D make it a useful tool for educational aims. [ABSTRACT FROM AUTHOR]

Students commonly exhibit serious spatial comprehension difficulties when they come to learning crystal systems. To solve this problem, an active methodology based on the use of a Didactic Virtual Tool (DVT)—developed by the authors—is presented in this paper. The students' opinion was obtained from a survey carried out on 40 mechanical engineering students. The analysis of the obtained results reveals that, by using this DVT, students achieve a better understanding of the contents where spatial difficulties often arise during conventional teaching. Several DVT features were highly valued by the students, e.g., didactic use was rated 9.5 out of 10 and the methodology using the DVT in the classroom was rated 8.5 out of 10. In addition, the results revealed two factors that the students considered essential for using a DVT, both related to the tool design: (i) the modern aspect, i.e., it is necessary to keep a DVT updated to avoid obsolescence; and (ii) the DVT must be appealing in order to attract the students' attention. [ABSTRACT FROM AUTHOR]

Plum pox virus (PPV, sharka) is a limiting factor for peach production, and no natural sources of resistance have been described. Recent studies, however, have demonstrated that grafting the almond cultivar "Garrigues" onto the "GF305" peach infected with Dideron-type (PPV-D) isolates progressively reduces disease symptoms and virus accumulation. Furthermore, grafting "Garrigues" onto "GF305" prior to PPV-D inoculation has been found to completely prevent virus infection, showing that resistance is constitutive and not induced by the virus. To unravel the phytohormone signaling of this mechanism, we analyzed the following phytohormones belonging to the principal hormone classes: the growth-related phytohormones cytokinin trans-zeatin (tZ) and the gibberellins GA3 and GA4; and the stress-related phytohormones ethylene acid precursor 1-aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA), and jasmonic acid (JA). PPV inoculation produced a significant increase in GA3 and ABA in peach, and these imbalances were related to the presence of chlorosis symptoms. However, grafting "Garrigues" almond onto the PPV-inoculated "GF305" peach produced the opposite effect, reducing GA3 and ABA contents in parallel to the elimination of symptoms. Our results showed the significant implication of SA in this induced resistance in peach with an additional effect on tZ and JA concentrations. This SA-induced resistance based in the decrease in symptoms seems to be different from Systemic Acquired Resistance (SAR) and Induced Systemic Resistance (ISR), which are based in other reactions producing necrosis. Further studies are necessary, however, to validate these results against PPV-D isolates in the more aggressive Marcus-type (PPV-M) isolates. [ABSTRACT FROM AUTHOR]

In plants, fruit ripening is a coordinated developmental process that requires the change in expression of hundreds to thousands of genes to modify many biochemical and physiological signal cascades such as carbohydrate and organic acid metabolism, cell wall restructuring, ethylene production, stress response, and organoleptic compound formation. In Prunus species (including peaches, apricots, plums, and cherries), fruit ripening leads to the breakdown of complex carbohydrates into sugars, fruit firmness reductions (softening by cell wall degradation and cuticle properties alteration), color changes (loss of green color by chlorophylls degradation and increase in non-photosynthetic pigments like anthocyanins and carotenoids), acidity decreases, and aroma increases (the production and release of organic volatile compounds). Actually, the level of information of molecular events at the transcriptional, biochemical, hormonal, and metabolite levels underlying ripening in Prunus fruits has increased considerably. However, we still poorly understand the molecular switch that occurs during the transition from unripe to ripe fruits. The objective of this review was to analyze of the molecular bases of fruit quality in Prunus species through an integrated metabolic, genomic, transcriptomic, and epigenetic approach to better understand the molecular switch involved in the ripening process with important consequences from a breeding point of view.

β-Glucosidase (EC 3.2.1.21) is a prominent member of the GH1 family of glycoside hydrolases. The properties of this β-glucosidase appear to include resistance to temperature, urea, and iodoacetamide, and it is activated by 2-ME, similar to other members. β-Glucosidase from chayote (Sechium edule) was purified by ionic-interchange chromatography and molecular exclusion chromatography. Peptides detected by LC-ESI-MS/MS were compared with other β-glucosidases using the BLAST program. This enzyme is a 116 kDa protein composed of two sub-units of 58 kDa and shows homology with Cucumis sativus β-glucosidase (NCBI reference sequence XP_004154617.1), in which seven peptides were found with relative masses ranging from 874.3643 to 1587.8297. The stability of β-glucosidase depends on an initial concentration of 0.2 mg/mL of protein at pH 5.0 which decreases by 33% in a period of 30 h, and then stabilizes and is active for the next 5 days (pH 4.0 gives similar results). One hundred μg/mL β-D-glucose inhibited β-glucosidase activity by more than 50%. The enzyme had a Km of 4.88 mM with p-NPG and a Kcat of 10,000 min(-1). The optimal conditions for the enzyme require a pH of 4.0 and a temperature of 50 °C.