Hospital-based screening outperforms primary care screening as a means of achieving hepatitis C virus micro-elimination.

AIM: To assess the respective performances of a HCV screening program in a hospital setting and a HCV screening model applied concomitantly in a primary care centre. METHODS: Adult patients consecutively admitted to hospital for ambulatory surgery were screened for anti-HCV antibodies (hospital screening cohort, HPSC), as were patients receiving blood tests for medical reasons in a primary care centre (primary care screening cohort, PCSC). Serum anti-HCV and HCV RNA levels were tested by ELISA and real-time PCR, respectively. RESULTS: Seroprevalence of HCV infection was 2.2 % in the HPSC and 1.4 % in the PCSC (p = 0.044). All viraemic patients (0.2 % in HPSC and 0.1 % in PCSC) were treated with direct-acting antivirals and 85.7 % experienced a sustained virological response. CONCLUSIONS: Hospital-based HCV screening outperformed primary care-centered screening, significantly increasing HCV case findings.

Supplementation with a Symbiotic Induced Neuroprotection and Improved Memory in Rats with Ischemic Stroke.

After an ischemic stroke, various harmful mechanisms contribute to tissue damage, including the inflammatory response. The increase in pro-inflammatory cytokines has been related to greater damage to the neural tissue and the promotion of neurological alterations, including cognitive impairment. Recent research has shown that the use of prebiotics and/or probiotics counteracts inflammation and improves cognitive function through the production of growth factors, such as brain-derived neurotrophic factor (BDNF), by reducing inflammatory molecules. Therefore, in this study, the effect of the symbiotic inulin and Enterococcus faecium on neuroprotection and memory improvement was evaluated in a rat model of transient middle cerebral artery occlusion (tMCAO). In order to accomplish this, the animals were subjected to ischemia; the experimental group was supplemented with the symbiotic and the control group with the vehicle. The neurological deficit as well as spatial and working memory were evaluated using the Zea Longa scale, Morris water maze, and the eight-arm maze tests, respectively. Infarct size, the levels of BDNF, and tumor necrosis factor-alpha (TNF-α) were also assessed. The results show that supplementation with the symbiotic significantly diminished the neurological deficit and infarct size, improved memory and learning, increased BDNF expression, and reduced TNF-α production. These findings provide new evidence about the therapeutic use of symbiotics for ischemic stroke and open up the possibilities for the design of further studies.

Isolation of Carbon Black from Soils by Dispersion for Analysis: Quantitation and Characterization by Field Flow Fractionation Techniques.

In the present work, a procedure based on a dispersive medium for carbon black (CB) isolation from soil samples for analysis was proposed for the first time. Polymeric and biological dispersants and a sequential use of both dispersants were assayed. Asymmetrical flow field flow fractionation with dynamic light scattering detector (AF4-DLS) and sedimentation field flow fractionation with multi-angle light scattering detector (SdF3-MALS) were used for CB quantitation and characterization in the achieved dispersions. Soil samples contaminated with CB were processed, and CB isolation depended on the solid size distribution and composition and dispersant nature. More quantitative isolations were achieved for the four soils treated by the biological dispersant. As the organic matter percentage is higher in soil, the CB isolation was better, varying between 75 and 99% with standard deviation (s) ⩽ 2% for all soils. A soil contaminated with a CB-based pigment paste was analyzed, achieving (99 ± 2)% expressed as expanded uncertainty (K = 2) of dispersive isolation by the biological dispersant, and the sampling was scaled to 250 g of soil with positive results. The procedure was completed by CB recovery to obtain a solid residue able to be reused if necessary. For the filter-aided recovery step, different membranes (fiberglass, nylon, and Teflon) with a pore size between 0.1 and 5 µm were tested. The quantitation of the CB retained in the filter was measured by diffuse reflectance spectroscopy. Teflon (0.10 µm) provided better results for CB recovery, and its re-dispersion was also studied with suitable results. Determination of CB from the filters by diffuse reflectance spectrometry provided the same results than AF4 for CB dispersions.

The Impact of an Antimicrobial Stewardship Clinical Pharmacy Specialist on Antimicrobial Days of Therapy through Education Driven Policies, Procedures, and Interventions.

The primary goal of antimicrobial stewardship is to improve patient outcomes and minimize the consequences of antibiotic use. Prospective audit and feedback cannot always be performed by an antimicrobial stewardship program member which is where policies, procedures and education can aid interventions. The purpose of this study was to evaluate the impact on antimicrobial days of therapy due to a dedicated clinical pharmacy specialist primarily responsible for developing policies and procedures and providing education. A pre-intervention and post-intervention retrospective analysis of antimicrobial days of therapy from September 2019-May 2020 and July 2020-March 2021 was performed. Inclusion criteria consisted of adults receiving IV vancomycin, azithromycin, meropenem, ciprofloxacin, and/or levofloxacin. Excluded criteria consisted of documented interventions that were not related to implemented policies and procedures or performed education and patients receiving antimicrobial surgical prophylaxis. The primary outcome was antimicrobial days of therapy. An average of 3.47 ± 2.46 days (pre-intervention, n = 203) and 3.21 ± 2.52 days (post-intervention, n = 203) were observed for the primary outcome (p < 0.04182). Pharmacists performed 75 interventions pre-intervention and 102 interventions post-intervention (p = 0.0092). The implementation of a dedicated antimicrobial stewardship clinical pharmacy specialist responsible for developing policies, procedures, and education successfully reduced antimicrobial days of therapy and documented interventions.

Biotechnological development of Trichoderma-based formulations for biological control.

Trichoderma spp. are a genus of well-known fungi that promote healthy growth and modulate different functions in plants, as well as protect against various plant pathogens. The application of Trichoderma and its propagules as a biological control method can therefore help to reduce the use of chemical pesticides and fertilizers in agriculture. This review critically discusses and analyzes groundbreaking innovations over the past few decades of biotechnological approaches to prepare active formulations containing Trichoderma. The use of various carrier substances is covered, emphasizing their effects on enhancing the shelf life, viability, and efficacy of the final product formulation. Furthermore, the use of processing techniques such as freeze drying, fluidized bed drying, and spray drying are highlighted, enabling the development of stable, light-weight formulations. Finally, promising microencapsulation techniques for maximizing the performance of Trichoderma spp. during application processes are discussed, leading to the next-generation of multi-functional biological control formulations. KEY POINTS: • The development of carrier substances to encapsulate Trichoderma propagules is highlighted. • Advances in biotechnological processes to prepare Trichoderma-containing formulations are critically discussed. • Current challenges and future outlook of Trichoderma-based formulations in the context of biological control are presented.

Determination of antioxidant activity by in situ synthesis of AgNPs using in-tube SPME coupled on-line to capillary liquid chromatography.

A chromatographic system based on in-tube SPME coupled to capillary LC-DAD has been used to study the synthesis of silver nanoparticles using polyphenols in different scenarios: excess of the reducing agent or of the silver salt, addition of the cationic surfactants, and thermal synthesis. The optimized synthesis conditions allowed to quantify the polyphenols used as reducing agents, such as Trolox and chlorogenic acid. Two chromatographic peaks with different absorption spectrum were monitored during the syntheses. Depending on the molar relationship, a linear relation between the area of the chromatographic peaks and the concentration of the silver or polyphenol was established. For stabilization of silver nanoparticles, different cationic surfactants were used allowing to evaluate the role of anion (chloride and bromide) and of the alkyl chain. The proposed methodology can be used to determine chlorogenic acid up to 3 mM with a detection limit of 34 µM at λ= 400 nm. Chlorogenic acid was determined in dietary products with successful results. Precision (RSD=10%) and recovery (97-100%) were also satisfactory.

Scientific evidence on the efficacy of effervescent tablets for cleaning removable prostheses. A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Scientific evidence to determine the optimal method of cleaning and disinfecting removable prostheses is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the effectiveness of effervescent tablets in the cleaning and sanitizing of removable prostheses compared with other chemical and physical methods by assessing the reduction of biofilm, microbial levels, and material stability. MATERIAL AND METHODS: A systematic literature search and meta-analysis was conducted in August 2021 in the MEDLINE/PubMed, Cochrane, Embase, Scopus, and Web of Science databases. Randomized and nonrandomized controlled clinical trials published in English were included without publication year limits. A total of 23 studies were included in the systematic review and 6 in the meta-analysis, which had been registered in the international prospective register of systematic reviews (PROSPERO) database (CRD42021274019). The Cochrane Collaboration tool was used to assess the risk of bias of randomized clinical trials. The physiotherapy evidence database (PEDro) scale was used to analyze the internal validity of clinical trials by assessing the quality of the data obtained. The studies included in the meta-analysis were combined by using a random-effects model with the inverse variance method. Publication bias was analyzed by using the Duvall and Tweedie trim-and-fill method. RESULTS: With regard to biofilm reduction, the standardized mean difference estimated with the 4 studies combined in the meta-analysis was P=.012: mean difference=-1.92; 95% confidence interval=-3.45 to -0.38, indicating a "large" effect of the combination of brushing and effervescent tablet versus brushing alone. To estimate the reduction in the total bacteria levels in the 3 combined studies, a "large" effect size was obtained for the combination of brushing and using an effervescent tablet versus brushing alone, P<.001: mean difference=-4.43; 95% confidence interval=-8.29 to -0.55. Finally, when the 3 studies were combined to assess the reduction of Candida or fungal infection, a "moderate" effect size was obtained for the combination of brushing combined with the use of an effervescent tablet, P<.001: mean difference=-0.78; 95% confidence interval=-1.19 to -0.37. CONCLUSIONS: The combination of brushing and the use of effervescent tablets versus brushing alone had a significantly higher effect on reducing biofilm and bacterial counts and a moderate effect on reducing Candida. Regarding color and dimensional stability, few studies were found, with the results depending on the concentration of the product and the immersion time of the device.

COVID-19 Severity and Survival over Time in Patients with Hematologic Malignancies: A Population-Based Registry Study.

Mortality rates for COVID-19 have declined over time in the general population, but data in patients with hematologic malignancies are contradictory. We identified independent prognostic factors for COVID-19 severity and survival in unvaccinated patients with hematologic malignancies, compared mortality rates over time and versus non-cancer inpatients, and investigated post COVID-19 condition. Data were analyzed from 1166 consecutive, eligible patients with hematologic malignancies from the population-based HEMATO-MADRID registry, Spain, with COVID-19 prior to vaccination roll-out, stratified into early (February-June 2020; n = 769 (66%)) and later (July 2020-February 2021; n = 397 (34%)) cohorts. Propensity-score matched non-cancer patients were identified from the SEMI-COVID registry. A lower proportion of patients were hospitalized in the later waves (54.2%) compared to the earlier (88.6%), OR 0.15, 95%CI 0.11-0.20. The proportion of hospitalized patients admitted to the ICU was higher in the later cohort (103/215, 47.9%) compared with the early cohort (170/681, 25.0%, 2.77; 2.01-3.82). The reduced 30-day mortality between early and later cohorts of non-cancer inpatients (29.6% vs. 12.6%, OR 0.34; 0.22-0.53) was not paralleled in inpatients with hematologic malignancies (32.3% vs. 34.8%, OR 1.12; 0.81-1.5). Among evaluable patients, 27.3% had post COVID-19 condition. These findings will help inform evidence-based preventive and therapeutic strategies for patients with hematologic malignancies and COVID-19 diagnosis.

On-Site Multisample Determination of Chlorogenic Acid in Green Coffee by Chemiluminiscent Imaging.

The potential of antioxidants in preventing several diseases has attracted great attention in recent years. Indeed, these products are part of a multi-billion industry. However, there is a lack of scientific information about safety, quality, doses, and changes over time. In the present work, a simple multisample methodology based on chemiluminiscent imaging to determine chlorogenic acid (CHLA) in green coffee samples has been proposed. The multi-chemiluminiscent response was obtained after a luminol-persulfate reaction at pH 10.8 in a multiplate followed by image capture with a charge-coupled device (CCD) camera as a readout system. The chemiluminiscent image was used as an analytical response by measuring the luminescent intensity at 0 °C with the CCD camera. Under the optimal conditions, the detection limit was 20 µM and precision was also adequate with RSD < 12%. The accuracy of the proposed system was evaluated by studying the matrix effect, using a standard addition method. Recoveries of chlorogenic acid ranged from 93-94%. The use of the CCD camera demonstrated advantages such as analysis by image inspection, portability, and easy-handling which is of particular relevance in the application for quality control in industries. Furthermore, multisample analysis was allowed by one single image saving time, energy, and cost. The proposed methodology is a promising sustainable analytical tool for quality control to ensure green coffee safety through dosage control and proper labelling preventing potential frauds.

Reliable assessment of carbon black nanomaterial of a variety of cell culture media for in vitro toxicity assays by asymmetrical flow field-flow fractionation.

Carbon black nanomaterial (CB-NM), as an industrial product with a large number of applications, poses a high risk of exposure, and its impact on health needs to be assessed. The most common testing platform for engineered (E)NMs is in vitro toxicity assessment, which requires prior ENM dispersion, stabilization, and characterization in cell culture media. Here, asymmetric flow field-flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series was used for the study of CB dispersions in cell culture media, optimizing instrumental variables and working conditions. It was possible to disperse CB in a non-ionic surfactant aqueous solution due to the steric effect provided by surfactant molecules attached on the CB surface which prevented agglomeration. The protection provided by the surfactant or by culture media alone was insufficient to ensure good dispersion stability needed for carrying out in vitro toxicity studies. On the other hand, cell culture media in combination with the surfactant improved dispersion stability considerably, enabling the generation of shorter particles and a more favourable zeta potential magnitude, leading to greater stability due to electrostatic repulsion. It was demonstrated that the presence of amino acids in the culture media improved the monodisperse nature and stability of the CB dispersions, and resulted in a turn towards more negative zeta potential values when the pH was above the amino acid isoelectric point (IEP). Culture media used in real cell culture scenarios were also tested, and in vitro toxicity assays were developed optimizing the compatible amount of surfactant.

Biopolymer-based emulsions for the stabilization of Trichoderma atrobrunneum conidia for biological control.

Trichoderma spp. are ubiquitous soil-borne fungi that are widely used in biological control to promote and regulate healthy plant growth, as well as protect against plant pathogens. However, as with many biological materials, the relative instability of Trichoderma propagules limits its practical use in industrial applications. Therefore, there has been significant research interest in developing novel formulations with various carrier substances that are compatible with these fungal propagules and can enhance the shelf-life and overall efficacy of the Trichoderma. To this end, herein, we investigate the use of a variety of biopolymers and nanoparticles for the stabilization of Trichoderma atrobrunneum T720 conidia for biological control. The best-performing agents-agar and cellulose nanocrystals (CNC)-were then used in the preparation of oil-in-water emulsions to encapsulate conidia of T720. Emulsion properties including oil type, oil:water ratio, and biopolymer/particle concentration were investigated with respect to emulsion stability, droplet size, and viability of T720 conidia over time. Overall, agar-based formulations yielded highly stable emulsions with small droplet sizes, showing no evidence of drastic creaming, or phase separation after 1 month of storage. Moreover, agar-based formulations were able to maintain ~ 100% conidial viability of T720 after 3 months of storage, and over 70% viability after 6 months. We anticipate that the results demonstrated herein will lead to a new generation of significantly improved formulations for practical biological control applications. KEY POINTS: • Various biopolymers were evaluated for improving the stability of Trichoderma conidia • Oil in water emulsions was prepared using cellulose nanocrystals and agar as interface stabilizers • Agar-based emulsions showed ~ 100% viability for encapsulated conidia after 3 months of storage.

Memory improvement in senile rats after prebiotic and probiotic supplementation is not induced by GLP-1.

INTRODUCTION: The mechanism underlying the memory improvement induced by prebiotic and probiotic supplementation remains unclear. Glucagon-like peptide type 1 (GLP-1) could play an important role since it is induced by prebiotics and enhances memory and learning. AIMS: We correlated the levels of GLP-1 with spatial memory in senile animals to determine its role in memory improvement after prebiotic and probiotic supplementation. METHODS: Senile rats were randomly assigned to four groups: (1) water (control); (2) Enterococcus faecium (probiotic); (3) agave inulin (prebiotic); and (4) E. faecium + agave inulin (symbiotic). Each supplement was administered by an orogastric cannula for 5 weeks. In the fifth week, spatial memory was assessed using the Morris Water Maze test (MWM). We extracted the hippocampus, intestine, and serum. GLP-1 levels were quantified by enzyme-linked immunosorbent assay. RESULTS: A significant decrease in escape latency time in the MWM was observed in all groups treated with supplements. The symbiotic group achieved the highest reduction (15.13 s ± 6.40) (p < 0.01). We did not find a significant increase in GLP-1 levels nor a direct correlation of its levels with spatial memory improvement (p > 0.05). CONCLUSION: Prebiotic and probiotic supplementation improved spatial memory in senile animals. However, this beneficial effect did not correlate with GLP-1 levels.

Improving Sustainability of the Griess Reaction by Reagent Stabilization on PDMS Membranes and ZnNPs as Reductor of Nitrates: Application to Different Water Samples.

A new approach based on the use of polydimethylsiloxane (PDMS) membranes doped with Griess reagents for in situ determination of NO2- and NO3-- in real samples is proposed. The influence of some doping compounds, on the properties of the PDMS membranes, such as tetraethyl orthosilicate (TEOS), or/and ionic liquids (OMIM PF6) has been studied. Membrane characterization was performed. To apply the procedure to NO3- determination, dispersed Zn nanoparticles (ZnNPs) were employed. The analytical responses were the absorbance or the RGB components from digital images. Good precision (RSD < 8%) and detection limit of 0.01 and 0.5 mgL-1 for NO2- and NO3-, respectively, were achieved. The approach was satisfactory when applied to the determination of NO2- and NO3- in drinking waters, irrigation and river waters, and waters from canned and fresh vegetables. The results obtained were statistically comparable with those by using nitrate ISE or UV measurement. This approach was transferred satisfactory to 96 wells for multianalysis. This study enables the improvement in the on-site determination of NO2- and NO3- in several matrices. It is a sustainable alternative over the reagent derivatizations in solution and presents several advantages such as being versatile, simplicity, low analysis time, cost, and energy efficiency. The response can be detected visually or by portable instruments such as smartphone.

Characterization and Quantitation of Carbon Black Nanomaterials in Polymeric and Biological Aqueous Dispersants by Asymmetrical Flow Field Flow Fractionation.

Characterization of carbon black (CB) nanomaterials is required in industrial and research areas. Hence, in this study, asymmetrical flow field flow fractionation coupled to UV-vis and DLS detectors in series (AF4-UV-vis-DLS) was studied to evaluate the CB dispersion behavior in polymeric and biological dispersants, given the relevance of these media in practical applications. Under the experimental conditions, the results indicated that polymeric and biological dispersions showed size distributions with hydrodynamic diameters of 404 and 175 nm, respectively, for a particle core diameter of 40 nm. The polymeric dispersant provided lower stability as a function of time than that achieved by the biological dispersant. AF4 allowed separation of different core-sized CB (40, 69, and 72 nm) according to their hydrodynamic size using cross-flow rates of 0.5 mL·min-1 and 1 mL·min-1 for polymeric and biological dispersants, respectively. The dilution of the polymeric dispersion with different real water matrices produced a dramatic loss of dispersion stability, this effect being negligible in the case of biological dispersions.

NQS-Doped PDMS Solid Sensor: From Water Matrix to Urine Enzymatic Application.

The development of in situ analytical devices has gained outstanding scientific interest. A solid sensing membrane composed of 1,2-naphthoquinone-4-sulfonate (NQS) derivatizing reagent embedded into a polymeric polydimethylsiloxane (PDMS) composite was proposed for in situ ammonium (NH4+) and urea (NH2CONH2) analysis in water and urine samples, respectively. Satisfactory strategies were also applied for urease-catalyzed hydrolysis of urea, either in solution or glass-supported urease immobilization. Using diffuse reflectance measurements combined with digital image processing of color intensity (RGB coordinates), qualitative and quantitative analyte detection was assessed after the colorimetric reaction took place inside the sensing membrane. A suitable linear relationship was found between the sensor response and analyte concentration, and the results were validated by a thymol-PDMS-based sensor based on the Berthelot reaction. The suggested sensing device offers advantages such as rapidity, versatility, portability, and employment of non-toxic reagents that facilitate in situ analysis in an energy-efficient manner.

Study of the Stability of Citrate Capped AgNPs in Several Environmental Water Matrices by Asymmetrical Flow Field Flow Fractionation.

Asymmetrical flow field-flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series, was tested for stability studies of dispersions of citrate-capped silver nanoparticles (AgNPs) in several water matrices. The main goal is to provide knowledge to understand their possible behavior in the environment for short times since mixturing (up to 180 min). Ultrapure (UPW), bottled (BW1, BW2), tap (TW), transitional (TrW) and sea water (SW) matrices were assayed. Observations were compatible with the aggregation of AgNPs, a change in the plasmon band and a size growth with time were done. Fractograms showed different evolution fingerprints in the function of the waters and batches. The aggregation rate order was BW2, SW, TrW, BW1 and TW, being BW2 the lowest and TW the highest. NP aggregation can be induced by increasing the salt concentration of the medium, however transitional and sea waters did not follow the rule. Both matrices presented a lower aggregation rate in comparison with other aqueous matrices with much lower ionic strength (BW1 and TW), which can be explained by the potential presence of dissolved organic matter and/or the high concentration of halides providing their stabilization and passivation, respectively. AF4 provides relevant information with respect to static DLS and UV-Vis Spectroscopy showing that at least two populations of aggregates with different sizes between them, depending on both, the mixture time for a given matrix and type of water matrix for the same time.

Polyamide-MIL-101(Cr) Thin Films Synthesized on Either the Outer or Inner Surfaces of a Polysulfone Hollow Fiber for Water Nanofiltration.

High-performance thin film nanocomposite (TFN) hollow fiber (HF) membranes, with MIL-101(Cr) MOF nanoparticles (52 ± 13 nm) embedded, have been synthesized with the polyamide layer formed either on the outer or inner surface of a polysulfone HF (250 and 380 µm ID and OD, respectively). The TFN_out membrane was developed using the conventional interfacial polymerization method, typically applied to obtain TFN flat membranes (MOF particles added to the thin layer by deposition). This membrane gave a water permeance value of 1.0 ± 0.7 L·m-2·h-1·bar-1 and a rejection of 90.9 ± 1.2% of acridine orange (AO, 265 Da). In contrast, the TFN_in membrane was synthesized by microfluidic means and gave a significantly higher water permeance of 2.8 ± 0.2 L·m-2·h-1·bar-1 and a slightly lower rejection of 87.4 ± 2.5% of the same solute. This remarkable increase of flux obtained with small solute AO suggests that the HF membranes developed in this work would exhibit good performance with other typical solutes with higher molecular weight than AO. The differences between the performances of both TFN_in and TFN_out membranes lay on the distinct superficial physicochemical properties of the support, the synthesis method, and the different concentrations of MOF present in the polyamide films of both membranes. The TFN_in is more desirable due to its potential advantages, and more effortless scalability due to the microfluidic continuous synthesis. In addition, the TFN_in membrane needs much fewer quantities of reactants to be synthesized than the TFN_out or the flat membrane version.

Habilidades Sociales y Aprendizaje Cooperativo el la Inclusión de Estudiantes con Necesidades Educativas Específicas / Social Skills and Cooperative Learning in the Inclusion of Students with Specific Educational Needs

RESUMEN Este estudio analiza cómo al trabajar con la metodología del aprendizaje cooperativo en el aula, los alumnos con necesidades educativas especiales pueden mejorar en sus habilidades sociales obteniendo mejores aprendizajes. Se realiza en el contexto del programa de formación docente universitaria del Experto en Aprendizaje Cooperativo online de la Universidad de Alcalá, en España. La metodología utilizada es de corte cualitativo en base a un diseño de estudio de casos desarrollado durante 6 años (2011 al 2017). Los participantes fueron 176 profesores de centros educativos españoles que cumplían los requisitos. Las acciones realizadas implicaron a un total de 3.964 estudiantes, de los cuales, 406 presentaban algún tipo de necesidad específica. Los resultados reflejan la influencia en las habilidades sociales de los alumnos con necesidades al trabajar con la metodología del aprendizaje cooperativo. Se concluye que para la mejora de las habilidades sociales del alumnado con necesidades es necesario que el docente potencie acciones que promuevan las habilidades sociales de estos alumnos a través del aprendizaje cooperativo y de las propuestas diversificadas, planificadas y ajustadas a sus necesidades concretas, dándoles la oportunidad de trabajar de forma conjunta con sus compañeros.

ABSTRACT This study analyzes how students with special educational needs can improve their social skills through better learning when working with the cooperative learning methodology in the classroom. The research was carried out as part of the Online Cooperative Learning Expert training program at the University of Alcalá, in Spain. The methodology used was qualitative based on a case study design developed over 6 years (2011 to 2017). The participants were 176 teachers from Spanish educational centers who met the requirements. The actions carried out involved a total of 3,964 students, of which 406 had some type of specific need. The results reflect the influence on the social skills of the students with needs when working with the cooperative learning methodology. It is concluded that for the improvement of the social skills of students with needs, it is necessary for the teacher to make use of actions that promote the social skills of these students through cooperative learning and diversified proposals, planned and adjusted to their specific needs, giving them the opportunity to work together with their peers.

Aqueous Dilution of Noble NPs Bulk Dispersions: Modeling Instability due to Dissolution by AF4 and Stablishing Considerations for Plasmonic Assays.

Among different nanomaterials, gold and silver nanoparticles (AuNPs and AgNPs) have become useful tools for a wide variety of applications in general, and particularly for plasmonic assays. Particle size and stability analysis are key elements for their practical applications since the NPs properties depend on these parameters. Hence, in the present work, asymmetrical flow field flow fractionation (AF4) coupled to UV-Vis and dynamic light scattering (DLS) detectors in series, has been evaluated for stability studies of citrate-capped AuNPs and AgNPs aqueous dispersions. First, experimental parameters, such as mobile phase or cross-flow rate were optimized. Sodium azide to pH 7 for AuNPs and pH 9.2 for AgNPs were selected as the optimum mobile phase. The analytical response of bulk dispersions of AuNPs (20, 40, 60 and 80 nm) and AgNPs (20, 40 and 60 nm) and their dilutions have been studied. Fractograms showed a decrease on the absorbance signal in diluted dispersions as a function of time and particle size for the diluted dispersions that can be explained by dissolution in diluted dispersion since hydrodynamic diameter was constant. The results indicated that the dependence of the signal with time was more intense for AgNPs than for AuNPs, which can be correlated with its lower stability. These findings should be considered when plasmonic assays are realized. Here, assays involving non-oxidant acidic acids as use cases, were tested for several batches of NPs and considerations about their stability and operability stablished.