Tidal volume selection in volume-controlled ventilation guided by driving pressure versus actual body weight in healthy anesthetized and mechanically ventilated dogs: A randomized crossover trial.

OBJECTIVE: To compare static compliance of the respiratory system (CstRS) and the ratio of partial pressure of end-tidal to arterial carbon dioxide (Pe'CO2/PaCO2), in healthy dogs using two approaches for tidal volume (VT) selection during volume-controlled ventilation: body mass based and driving pressure (ΔPaw) guided. STUDY DESIGN: Randomized, nonblinded, crossover, clinical trial. ANIMALS: A total of 19 client-owned dogs anesthetized for castration and ovariohysterectomy. METHODS: After a stable 10 minute baseline, each dog was mechanically ventilated with a VT selection strategy, randomized to a constant VT of 15 mL kg-1 of actual body mass (VTBW) or ΔPaw-guided VT (VTΔP) of 7-8 cmH2O. Both strategies used an inspiratory time of 1 second, 20% end-inspiratory pause, 4 cmH2O positive end-expiratory pressure and fraction of inspired oxygen of 0.4. Respiratory frequency was adjusted to maintain Pe'CO2 between 35 and 40 mmHg. Respiratory mechanics, arterial blood gases and Pe'CO2/PaCO2 were assessed. Continuous variables are presented as mean ± SD or median (interquartile range; quartiles 1-3), depending on distribution, and compared with Wilcoxon signed-rank tests. RESULTS: The VT was significantly higher in dogs ventilated with VTΔP than with VTBW strategy (17.20 ± 4.04 versus 15.03 ± 0.60 mL kg-1, p = 0.036). CstRS was significantly higher with VTΔP than with VTBW strategy [2.47 (1.86-2.86) versus 2.25 (1.79-2.58) mL cmH2O-1 kg-1, p = 0.011]. There were no differences in Pe'CO2/PaCO2 between VTΔP and VTBW strategies (0.94 ± 0.06 versus 0.92 ± 0.06, p = 0.094). No discernible difference in ΔPaw was noted between the strategies. CONCLUSIONS AND CLINICAL RELEVANCE: While no apparent difference was observed in the Pe'CO2/PaCO2 between the VT selection strategies employed, CstRS significantly increased during the VTΔP approach. A future trial should explore if VTΔP improves perioperative gas exchange and prevents lung damage.

Ultrasound-guided caudal quadratus lumborum block combined with the greater ischiatic notch plane block as motor-protective analgesia for the pelvic limb in dogs.

OBJECTIVE: To develop an ultrasound-guided caudal quadratus lumborum block (C-QLB) technique in canine cadavers and to compare sensory and motor blockade resulting from the combination of ultrasound-guided greater ischiatic notch (GIN) plane and C-QLB approaches (GIN-CQLB group) versus a lumbosacral plexus (LSP group) approach [combination of lateral pre-iliac (LPI) and parasacral (PS) techniques] in dogs. STUDY DESIGN: Descriptive anatomical study and prospective randomized, blinded, experimental crossover trial. ANIMALS: A total of six canine cadavers and six adult Beagle dogs. METHODS: Phase I: following ultrasound-guided C-QLB injections of 0.3 mL kg-1 of dye, using the interfascial plane located lateral to the quadratus lumborum muscle at the level of the sixth lumbar vertebra (L6) as injection point, the spread of injectate and nerve staining was evaluated using gross anatomical dissection. PHASE II: sensory and motor blockade achieved with the GIN-CQLB or LSP blocks in Beagle dogs were evaluated and compared. The assigned technique was performed with 2% lidocaine: 0.2 mL kg-1 for the GIN and PS approaches and 0.3 mL kg-1 for the C-QLB and LPI approaches. RESULTS: Dissection revealed distribution of dye around the lumbar hypaxial musculature, extending into the paravertebral spaces, with staining of 3 (2-4) [median (interquartile range)] spinal nerves, spanning L3 to L6. The median motor blockade in the GIN-CQLB and LSP groups was 7 (7-8) versus 16 (10-16) (p = 0.026), whereas the median sensory blockade was 5 (4-5) versus 3 (3-3) (p = 0.025), respectively. CONCLUSION AND CLINICAL SIGNIFICANCE: The GIN-CQLB approach desensitized the thigh dermatomes effectively. Compared with the LSP approaches, GIN-CQLB exhibits a motor-protective effect by preserving tonic muscle function.

Ultrasound-guided lateral pericapsular hip desensitization of the articular branches of the cranial gluteal nerve: A canine cadaveric study and feasibility study in dogs.

OBJECTIVE: To develop and assess the feasibility, as a diagnostic block, of an ultrasound-guided lateral pericapsular hip desensitization (L-PHD) technique in dogs. STUDY DESIGN: Prospective, randomized, anatomical and feasibility study. ANIMALS: A total of 11 canine cadavers and eight adult dogs scheduled for acetabular surgical denervation. METHODS: After studying the ultrasound anatomy of the lateral aspect of the gluteal region and determining an acoustic window to perform an ultrasound-guided L-PHD in three canine cadavers, the right and left hemipelves of eight canine cadavers were injected in the interfascial plane located lateral (LL-PHD group) or medial (LM-PHD group) to the deep gluteal muscle, with 0.05 mL kg-1 of dye per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection. Then, the LM-PHD was performed using 2% lidocaine as a diagnostic block in dogs scheduled for acetabular surgical denervation. Positive predictive value (PPV) was calculated for those animals who had favorable outcomes after acetabular surgical denervation. RESULTS: The ultrasound-guided LL-PHD and LM-PHD could be performed by inserting the needle lateral and medial to the deep gluteal muscle. Ultrasound-guided LL-PHD stained the cranial gluteal nerve and its muscular branches in all injections and partially stained the lumbosacral trunk in two out of eight cadavers. The LM-PHD selectively stained the articular branches of the cranial gluteal nerve in all but one cadaver. The PPV for LM-PHD successful test prediction was 85.7% (95% confidence interval: 48.6% to 98.6%). CONCLUSIONS: and clinical significance Ultrasound-guided LM-PHD using 0.05 mL kg-1 of dye selectively stained the articular branches of the cranial gluteal nerve in canine cadavers. The LM-PHD technique is feasible and could be used as a diagnostic block before acetabular surgical denervation in dogs.

Efficacy of tramadol for postoperative pain management in dogs: systematic review and meta-analysis.

OBJECTIVE: To evaluate the evidence of analgesic efficacy of tramadol for the management of postoperative pain and the presence of associated adverse events in dogs. DATABASES USED: A comprehensive search using PubMed/MEDLINE, LILACS, Google Scholar and CAB databases with no restrictions on language and following a prespecified protocol was performed from June 2019 to July 2020. Included were randomized controlled trials (RCTs) performed in dogs that had undergone general anesthesia for any type of surgery. Two authors independently classified the studies, extracted data and assessed their risk of bias using Cochrane's tool. RevMan and GRADE methods were used to rate the certainty of evidence (CoE). CONCLUSIONS: Overall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26-0.85; I2 = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20-1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16-3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00-0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95% CI: 0.66-18.08; I2 = 43%) and COX inhibitors (low CoE; RR: 2.27; 95% CI: 0.68-7.60; I2 = 45%). Compared with multimodal therapy, tramadol administration may make minimal to no difference in the requirement for rescue analgesia (low CoE; RR: 1.12; 95% CI: 0.48-2.60; I2 = 0%). Adverse events were inconsistently reported and the CoE was very low. The overall CoE of the analgesic efficacy of tramadol for postoperative pain management in dogs was low or very low, and the main reasons for downgrading the evidence were risk of bias and imprecision.

[Application of eHealth in the Cuban contextAplicação da eSaúde no contexto cubano]. / Aplicación de la eSalud en el contexto cubano.

The achievements and challenges arising from the application of eHealth in the Cuban context to support universal health are presented. The Ministry of Public Health defined the Computerization Strategy, whose lines of work are based on the components declared in the Strategy and Plan of Action on eHealth of the Pan American Health Organization, and in the Policy for the Computerization of the Society, approved by the Cuban Government. The paper describes the actions of the Cuban strategy elaborated to solve the limitations in the technological infrastructure, to develop the platforms, the tools and the applications required by the health services, and to stimulate the professionals' abilities to use them. The results of eHealth in Cuba are based on the application and evaluation of the strategy implemented in the framework of the improvement of the health sector through projects such as the electronic medical record called Galen Clínicas, the training of human resources and the resources for information and education from the Infomed Health Telematics Network. These models of solidarity and collaborative networking have contributed to universal health and positively impacted on the health system beyond the borders. The challenges of eHealth are the development of initiatives in mobile health -in which there is little experience-; telemedicine -a project that is stopped-; integration and interoperability among applications; the sustainability of the implemented solutions; insufficient technological infrastructure; and strengthening of the legal framework.

As descobertas e desafios decorrentes da aplicação da eSaúde no contexto cubano para apoiar a saúde universal são expostos. O Ministério da Saúde Pública definiu a Estratégia de informatização, cujas linhas de trabalho são baseadas nos componentes declarados na Estratégia e Plano de Ação da eSaúde da Organização Pan-Americana da Saúde e na Política de Informatização da Sociedade aprovada pelo governo cubano. O artigo especifica as ações da estratégia cubana para resolver as limitações da infra- estrutura tecnológica, desenvolver plataformas, ferramentas e aplicações que exigem serviços de saúde, e estimular nos profissionais as habilidades para usá-los. Os resultados da eSaúde em Cuba são o produto da aplicação e avaliação da estratégia aplicada no âmbito da melhoria do setor da saúde, através de projetos como o registro médico eletrônico chamado Galen Clínicas, a preparação do capital humano e os recursos de informação e educação a distância da Rede Telémática de Saúde Infomed. Estes modelos de solidariedade e trabalho colaborativo em redes contribuíram para a saúde universal e impactaram positivamente no sistema de saúde, além das fronteiras. Os desafios da eSaúde consistem no desenvolvimento de iniciativas em saúde móvel, em que há pouca experiência; telemedicina, cujo projeto foi interrompido; a integração e interoperabilidade das aplicações; a sustentabilidade das soluções implementadas; a infra-estrutura tecnológica insuficiente; e o fortalecimento do quadro legal.

Optimization of the excitation frequency for high probe sensitivity in single-eigenmode and bimodal tapping-mode AFM.

The cantilever excitation frequency and tip free oscillation amplitude are two critical imaging parameters in amplitude-modulation atomic force microscopy (AM-AFM, often referred to as tapping-mode AFM). In general, the excitation frequency is selected to be 'near' the measured resonance frequency of the probe, but there is no established systematic approach for making that choice. In this work we show that the choice of excitation frequency can play a very significant role in the characterization of viscoelastic materials, even when considering small deviations with respect to the resonance frequency. Additionally, we offer an analytical expression, verified through experiments and numerical simulations, which offers guidance for selecting the drive frequency that maximizes probe sensitivity. Our approach is illustrated experimentally through single-eigenmode and bimodal AFM measurements performed on spin-coated Nafion(®) proton exchange thin films. We find that very often, the phase contrast channel is optimized by selecting an excitation frequency that is not necessarily at or near the free resonance frequency.

GSK-3 kinase a putative therapeutic target in trypanosomatid parasites.

Trypanosomatids are an important group of parasites that predominate in tropical and subtropical areas of the planet, which cause diseases that are classified as forgotten and neglected by the world health organization. In this group of parasites, we find Trypanosoma cruzi, Trypanosoma brucei, Trypanosoma brucei rhodesiense and Leishmania spp, for which there is no vaccine available, and its control has focused mainly on pharmacological treatment. Due to the poverty situation where these diseases are found and the biological complexity of these parasites, there are multiple variables to control, including the diversity of species, the complexity of their life cycles, drug resistance, cytotoxicity, the limited use in pregnant women, the high costs of treatment and the little-known pharmacological mechanisms of action, among others. It is therefore necessary to find new strategies and approaches for the treatment of these parasitic diseases. Among these new approaches is the rational search for new targets based on the allosteric inhibition of protein kinases, which have been little studied in trypanosomatids. Among these kinases, we find Glycogen Synthase Kinase-3 (GSK-3), a kinase of great pharmacological interest, which is under intense basic and clinical research by pharmaceutical companies for the treatment of cancer. This kinase, highly studied in the PI3K/AKT/mTOR pathway signaling in humans, has an orthologous gene in these parasites (GSK-3 s), which has proven to be essential for them in response to different challenges; Therefore, it is notable to increase research in this kinase in order to achieve a broad structural and functional characterization in the different species of trypanosomatids.

Electrically evoked stapedial reflex threshold and behavioral method usefulness in the cochlear implant programming in pediatric population.

OBJETIVE: To determine the utility of the electrically evoked stapedial reflex test (ESRT) and behavioral method in the CIs programming as an objective method to identify MCL levels in the CIs programming in pediatric patients. METHOD: Cross-sectional cohort study that included 20 pediatric patients with postlingual deafness and CI unilateral. They were performed clinical history, tympanometry, ESRT and by free field audiometry, before and after programming modifications according to MCL levels obtained by ESRT were performed. ESRT threshold was assessed with individual 300 ms stimuli on the 12 electrodes and recorded through manual decay. Likewise, the maximum comfort threshold (MCL) of each electrode was obtained through a behavioral analysis. RESULTS: No significant differences were found between the ESRT and behavioral method in MCLs levels in each of the electrodes evaluated. In addition, the correlation coefficients were significant and located in a range of 0.55-0.81, higher in electrodes 7, 8, and 9 (r = 0.77, 0.76, and 0.81, respectively). However, the median hearing threshold established by the ESRT was significantly lower compared to the behavioral threshold (36.0 vs. 47.0 dB, p < 0.0001), regardless of age (p = 0.249) or the etiology of hearing loss (p = 0.292). The difference between the tests was in the number of times to do it, the ESRT was done once and the behavioral on average 4 ± 1 times. CONCLUSION: Similar MCL thresholds were obtained in both ESRT and behavioral test, establishing that both methods are reliable for use in pediatric patients; however, ESRT allows shortening the time to achieve normal hearing and language acquisition thresholds in a more optimal time.

Monitoring of (bio)available labile metal fraction in a drinking water treatment plant by diffusive gradients in thin films.

A performance study of diffusive gradients in thin films (DGT) and inductively coupled plasma optical emission spectrometry (ICP-OES) was applied for the monitoring of the labile fraction of metals Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn, in Sant Joan Despí Drinking Water Treatment Plant located in the South of Barcelona's Metropolitan Area (Spain). The DWTP monitoring protocol was optimized by working for 1 day of deployment (24 h) with the DGT device in contact with both treated and river water matrixes. Additionally, it was demonstrated that an increase in the deployment time of 1 week did not decrease the evaluated concentrations of the studied metals. The quality parameters of the DGT device and ICP-OES determination, such as limit of quantification, accuracy expressed as relative error (%) and reproducibility expressed as relative standard deviation, were evaluated. Good results were obtained for all the metals in ultrapure water; limits of quantification ranged from 1.5 µg L( - 1) for cadmium to 28 µg L( - 1) for zinc when deployment time of 24 h was used and from 0.2 µg L( - 1) for cadmium to 4 µg L( - 1) for zinc when this time was increased by 1 week. Accuracy and precisions lower than or equal to 10% were obtained at a parametric concentration value of the metals regulated in the European Drinking Water Guidelines (98/83/EC). DGT deployment was tested in river and treated water, and good results were obtained for Cd, Ni, Co and Zn, whereas for the other metals, a continuous control of their metallic labile fractions was monitored. Therefore, DGT device allows the continuous monitoring of the labile metal species in a drinking water treatment plant.

Engineering, Recyclable, and Biodegradable Plastics in the Automotive Industry: A Review.

The automotive industry has used plastics almost since the beginning. The lightness, flexibility, and many qualities of plastics make them ideal for the automotive industry, reducing cars' overall weight and fuel consumption. Engineering plastics in this industry belong to the high-performance segment of non-renewable resources. These plastics exhibit higher properties than commodity plastics. Fortunately, unlike recycled commodity plastics, the super properties and high-performance characteristics make engineering plastics effectively reused after recycling. The substitution of these fossil-fuel-derived plastics adds to the solution of lightweighting, a much-needed solution to waste management, and solves industrial and ecological issues surrounding plastic disposal. All major vehicle manufacturers worldwide use bioplastics and bio-based plastics, including natural-fiber composites and engineering plastics reinforced with natural fibers. Changing the source of plastics to raw materials from renewable resources is the logical approach to sustainability. Thus, high-quality plastics, recycled plastics, bio-based plastics, and biodegradable plastics could be exploited from design, making sustainability an integral concept of mobility development. This review analyzes that switching from fossil-fuel- to renewable-sources-derived plastics is a step toward meeting the current environmental goals for the automotive industry, including electric cars.

Measuring Online Teaching Service Quality in Higher Education in the COVID-19 Environment.

The use of the Internet to develop new technologies has generated a considerable change in teaching and student learning in higher education. The pandemic caused by COVID-19 has forced universities to switch from face-to-face to online instruction. Furthermore, this transfer process was planned and executed quickly, with urgent redesigns of courses originally conceived for live teaching. The aim of this work is to measure the service quality of online teaching delivered during the COVID-19 period. The methodology was based on an importance-performance analysis using a structural equations model. The data were obtained from a sample of 467 students attending a university in southern Spain. The results reveal five priority attributes of online teaching that need to be improved in order to enhance the service quality of the virtual instruction provided to students. Universities need to redefine their online format by integrating methodological and technological decisions and involving collaboration between teachers, students and administration staff and services. The results do not apply to educational institutions that exclusively teach courses online, but to those institutions that had to rapidly adapt, and shift course material originally designed for face-to-face training.

[Heavy metal distribution in superficial sedimenta ta Saco, Gulf of Cariaco, Sucre, Venezuela]. / Distribución de metales pesados en los sedimentos superficiales del Saco del Golfo de Cariaco, Sucre, Venezuela.

The Gulf of Cariaco is a marine ecosystem with high primary productivity, which gives it an ecological and socioeconomic importance. Nevertheless, anthropogenic activities around the Gulf produce wastes that are deposited directly or by runoff into the sediments, and consequently, increases concentrations of metals in this ecosystem. The objective of this study was to determine the distribution of cadmium, copper, lead, manganese, nickel and zinc in geochemical fractions of surface sediments, using modified BCR sequential extraction procedure. The concentrations were measured using flame atomic absorption spectroscopy. In addition, the contents of soluble and exchangeable metals associated to carbonate fractions, determined by BCR, were compared with those determined by the method of Campanella. Samples were collected in 12 stations during June 2007. The applied methodologies were evaluated with a certified reference material of marine sediments (HISS-1) and the results indicated that these methods provide adequate accuracy and precision for the extraction of metals. The total metal concentrations (microg g(-1)) were, Cd: < limit of detection (LD)-5.0; Pb: 1.79-60.41; Cu: no detected (ND)-42.18; Zn: 25.13-104.57; Mn: 66.31-80.29 and Ni: 3.29-24.58. Cd, Cu, Ni and Pb at several stations, exceeded the Canadian Sediment Quality Guidelines of the Lowest Effect Levels (LEL). Cadmium was identified as being the most mobile of the elements, having the highest concentrations in soluble and exchangeable cations and carbonates. However, Pb, Cu, Mn and Zn levels were found highly associated to organic matter and sulfide fractions. The methods did not show significant statistical differences for the extraction of soluble and exchangeable cations and the metals associated to carbonate fraction. There are several significant correlations between heavy metals, which suggest their common origin.

Spanish Neurohistology: Maturity and Evolution of a Research School.

During the early 20th century, a neurobiological research school combining diverse scientific approaches (basic neurohistology, anatomical pathology, neurology, and psychiatry) emerged around the figure of Santiago Ramón y Cajal (1852-1934). In the 1920s, a new building was erected and it was to become the major Spanish neurobiological research center. It was an oversized project that, unfortunately, did not facilitate the definitive consolidation of a Spanish neurohistological school. Later, the Civil War and the early years of Franco's dictatorship brought about the slow decline of this research group. Anat Rec, 303:1242-1251, 2020. © 2019 American Association for Anatomy.

GSK-3 kinase a putative therapeutic target in trypanosomatid parasites

ABSTRACT Trypanosomatids are an important group of parasites that predominate in tropical and subtropical areas of the planet, which cause diseases that are classified as forgotten and neglected by the world health organization. In this group of parasites, we find Trypanosoma cruzi, Trypanosoma brucei, Trypanosoma brucei rhodesiense and Leishmania spp, for which there is no vaccine available, and its control has focused mainly on pharmacological treatment. Due to the poverty situation where these diseases are found and the biological complexity of these parasites, there are multiple variables to control, including the diversity of species, the complexity of their life cycles, drug resistance, cytotoxicity, the limited use in pregnant women, the high costs of treatment and the little-known pharmacological mechanisms of action, among others. It is therefore necessary to find new strategies and approaches for the treatment of these parasitic diseases. Among these new approaches is the rational search for new targets based on the allosteric inhibition of protein kinases, which have been little studied in trypanosomatids. Among these kinases, we find Glycogen Synthase Kinase-3 (GSK-3), a kinase of great pharmacological interest, which is under intense basic and clinical research by pharmaceutical companies for the treatment of cancer. This kinase, highly studied in the PI3K/AKT/mTOR pathway signaling in humans, has an orthologous gene in these parasites (GSK-3 s), which has proven to be essential for them in response to different challenges; Therefore, it is notable to increase research in this kinase in order to achieve a broad structural and functional characterization in the different species of trypanosomatids.

[Impact of the financial crisis on activity and efficiency at a high-technology university hospital]. / Impacto de la crisis económica en la actividad y eficiencia de un hospital terciario universitario.

OBJECTIVE: The financial crisis that begun in 2008 significantly decreased the budget of the public health system on Spain. The aim of this study was to evaluate the impact of the financial crisis on the activity, quality and efficiency of a high-technology university hospital. METHODS: We retrospectively analyzed the outcomes of four sets of hospital management indicators between 2007 and 2016 (A: activity; B: quality and complexity of inpatientcare; C: staff, global production and budget expenses; D: patients satisfaction survey). The data were obtained from the center's information systems and treated as longitudinal series of descriptive type. The impact of the crisis was assessed by analyzing the percentage deviations of the different indicators in relation to the values of the year 2009, the year before initial budget adjustments. RESULTS: The overall activity of the hospital, adjusted for complexity, decreased 9% during the first two years of the crisis and recovered later. Inpatient complexity increased 14%. Quality set indicators did not deteriorate. Expenses decreased 16% between the years 2009 and 2014, and efficiency and global productivity improved by 13%. Patient satisfaction survey results did not change. CONCLUSIONS: The financial crisis and the subsequent decrease of budget provoked an initial reduction of hospital activity, associated with a complexity increase. It was progressively made up for with increased efficiency and global productivity. The financial crisis did not have negative effects on quality of care or patient satisfaction.

OBJETIVO: La crisis económica iniciada el año 2008 provocó una caída importante del gasto sanitario público en España. El objetivo del estudio fue evaluar el impacto de la crisis en la actividad, calidad y eficiencia de un hospital terciario universitario de alta complejidad. METODOS: Se analizó retrospectivamente la evolución entre los años 2007 y 2016 de cuatro grupos de indicadores de gestión (A: actividad asistencial; B: calidad y complejidad de las altas; C: plantilla, producción global y gasto; D: satisfacción de los pacientes hospitalizados). Los datos se obtuvieron de los sistemas de información del centro y se trataron como series longitudinales de tipo descriptivo. El impacto de la crisis se valoró analizando las desviaciones porcentuales de los diferentes indicadores en relación a los valores del año 2009, el año previo al inicio de los ajustes presupuestarios. RESULTADOS: La actividad global ajustada por complejidad disminuyó un 9% los dos primeros años de la crisis, y se recuperó en los años posteriores. La complejidad de los pacientes hospitalizados se incrementó en un 14%. Los indicadores de calidad no se deterioraron. El gasto ejecutado anual disminuyó un 16% entre el 2009 y el 2014, y la eficiencia y la productividad global aumentaron un 13%. Los indicadores de satisfacción no se modificaron. CONCLUSIONES: La crisis económica y la consecuente reducción del presupuesto y del gasto provocaron una disminución inicial de la actividad del centro, asociada a un incremento de la complejidad, que fue compensada progresivamente gracias a una mejora en la eficiencia y en la productividad global. La crisis no impactó negativamente ni en la calidad ni en la satisfacción de los pacientes atendidos en régimen de hospitalización.

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy.

Organic photovoltaic systems comprising donor polymers and acceptor fullerene derivatives are attractive for inexpensive energy harvesting. Extensive research on polymer solar cells has provided insight into the factors governing device-level efficiency and stability. However, the detailed investigation of nanoscale structures is still challenging. Here we demonstrate the analysis and modification of unidentified surface aggregates. The aggregates are characterized electrically by Kelvin probe force microscopy and conductive atomic force microscopy (C-AFM), whereby the correlation between local electrical potential and current confirms a defective charge transport. Bimodal AFM modification confirms that the aggregates exist on top of the solar cell structure, and is used to remove them and to reveal the underlying active layer. The systematic analysis of the surface aggregates suggests that the structure consists of PCBM molecules.

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation.

Bioinspired design has been central in the development of hierarchical nanocomposites. Particularly, the nacre-mimetic brick-and-mortar structure has shown excellent mechanical properties, as well as gas-barrier properties and optical transparency. Along with these intrinsic properties, the layered structure has also been utilized in sensing devices. Here we extend the multifunctionality of nacre-mimetics by designing an optically transparent and electron conductive coating based on PEDOT:PSS and nanoclays Laponite RD and Cloisite Na+. We carry out extensive characterization of the nanocomposite using transmittance spectra (transparency), conductive atomic force microscopy (conductivity), contact-resonance force microscopy (mechanical properties), and SEM combined with a variety of stress-strain AFM experiments and AFM numerical simulations (internal structure). We further study the nanoclay's response to the application of pressure with multifrequency AFM and conductive AFM, whereby increases and decreases in conductivity can occur for the Laponite RD composites. We offer a possible mechanism to explain the changes in conductivity by modeling the coating as a 1-dimensional multibarrier potential for electron transport, and show that conductivity can change when the separation between the barriers changes under the application of pressure, and that the direction of the change depends on the energy of the electrons. We did not observe changes in conductivity under the application of pressure with AFM for the Cloisite Na+ nanocomposite, which has a large platelet size compared with the AFM probe diameter. No pressure-induced changes in conductivity were observed in the clay-free polymer either.

Gastropod (Otala lactea) shell nanomechanical and structural characterization as a biomonitoring tool for dermal and dietary exposure to a model metal.

Metallic tungsten (W) was initially assumed to be environmentally benign and a green alternative to lead. However, subsequent investigations showed that fishing weights and munitions containing elemental W can fragment and oxidize into complex monomeric and polymeric tungstate (WO4) species in the environment; this led to increased solubility and mobility in soils and increased bioaccumulation potential in plant and animal tissues. Here we expand on the results of our previous research, which examined tungsten toxicity, bioaccumulation, and compartmentalization into organisms, and present in this research that the bioaccumulation of W was related to greater than 50% reduction in the mechanical properties of the snail (Otala lactea), based on depth-sensing nanoindentation. Synchrotron-based X-ray fluorescence maps and X-ray diffraction measurements confirm the integration of W in newly formed layers of the shell matrix with the observed changes in shell biomechanical properties, mineralogical composition, and crystal orientation. With further development, this technology could be employed as a biomonitoring tool for historic metals contamination since unlike the more heavily studied bioaccumulation into soft tissue, shell tissue does not actively eliminate contaminants.

Determination of odorous mixed chloro-bromoanisoles in water by solid-phase micro-extraction and gas chromatography-mass detection.

A headspace-solid-phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) method has been proposed for the simultaneous determination of odorous trihalogenated anisoles in water. Parameters affecting efficiency of HS-SPME procedure, such as the selection of the SPME coating, extraction time, temperature and ionic strength were optimized. The commercially available polydimethylsiloxane (PDMS 100 microm) fiber appears to be the most suitable for the simultaneous determination of these compounds. Run-to-run precision with relative standard deviations (R.S.D.s) between 5 and 15% were obtained for most of the compounds except for 2,5-dicloro-6-bromo-anisole, 2,3-dibromo-6-chloroanisole, pentachloro- and pentabromoanisole (>20%). The method was linear over two orders of magnitude, and detection limits were compound dependent and ranged from 0.03 ng/L for 2,4,6-trichloroanisole to 0.25 ng/L for 2,3-dibromo-6-chloroanisole. The HS-SPME-GC-MS procedure was tested using real samples and relatively good standard deviations were obtained when using p-iodoanisole as internal standard for quantification. This is the first time that the individual identification of odorous trihalogenated chloro-bromoanisoles has been reported, being HS-SPME-GC-MS a suitable method for simultaneous determination of these compounds in water at concentration levels below their odor limit of detection.

Determination of the odor threshold concentrations of chlorobrominated anisoles in water.

Trihalophenols, which are drinking water disinfection byproducts (DBPs) formed by chlorination or chloramination practices, can be biomethylated into trihalogenated anisoles. These latter compounds have traditionally been suspected of causing odor episodes in drinking water around the world. The odor threshold concentration (OTC) of mixed chlorobrominated anisoles, which were previously synthesized, was determined by flavor profile analysis (FPA) performed by an experienced panel trained to identify odors and tastes in water. The odor threshold amount (OTA) was evaluated by using a gas chromatograph equipped with olfactometry (GC-O) and electron capture detectors (ECD). FPA results for mixed chlorobromoanisoles gave a theoretical OTCs range from 2 to 30 ng/L, the 2,6-diBr-3Cl-anisole being the most odorous compound. Rubber is the general descriptor described by panelists for these compounds, although earthy and musty are the following most cited descriptors.