1,245 research outputs found

    Evolucion morfologica del aparato digestivo de postlarvas y prejuveniles de Prochilodus lineatus (Val., 1847) (Pisces, Curimatidae) y su relacion con la dieta

    Get PDF
    Le "sabalo" (#Prochilodus lineatus) est une espèce les plus importantes de poissons du Parana. Le régime alimentaire est détritivore chez l'adulte. Cet article présente l'analyse du régime alimentaire des post-larves et préjuvéniles de #Prochilodus lineatus capturé dans la rivière Salado (Santo Tomé, Argentina) et sa relation avec les changements dans la dentition et la morphologie de l'appareil digestif intervenant au cours de la croissance. Au stade de post-larves, l'espèce est planctophage, les cladocères étant la nourriture la plus importante en nombre et en occurence. L'intestin est un tube simple et court et les dents orales et du pharynx sont coniques et insérées sur les os. Le régime change avec la croissance : moins de microcrustacés et plus d'algues, de rotifères, de protozoaires et de détritus. L'appareil digestif s'allonge et présente la conformation de l'adulte ; les dents orales sont spatulées et fixées sur les lèvres et les dents pharyngiennes inférieures sont reabsorbées. Les modifications dans l'appareil de filtration permettent la rétention de particules de petite taille. (Résumé d'auteur

    Stereolithography 3D-Printed Catalytically Active Devices in Organic Synthesis

    Get PDF
    This article describes the synthesis of stereolithography (SLA) 3D-printed catalyst-impregnated devices and their evaluation in the organocatalyzed Friedel\u2013Crafts alkylation of N\u2013Me\u2013indole with trans--nitrostyrene. Using a low-cost SLA 3D printer and freeware design software, dierent devices were designed and 3D-printed using a photopolymerizable resin containing a thiourea-based organocatalyst. The architectural control oered by the 3D-printing process allows a straightforward production of devices endowed with dierent shapes and surface areas, with high reproducibility. The 3D-printed organocatalytic materials promoted the formation of the desired product up to a 79% yield, although with longer reaction times compared to reactions under homogeneous conditions

    The environmental noise level in the rejuvenation pruning on centuries-old olive tree

    Get PDF
    ArticleIn the Italian agricultural economy, olive cultivation plays a fundamental role, and this is especially true for the southern regions where almost all cultivation is spread. In Calabria, in particular, olive cultivation has seen over the last few decades significantly improve the quality of production also as a result of investments aimed at the creation of new mechanizable plants and/or the modernization of existing ones; today some areas have got both PDO and PGI certification. In the ‘Piana di Gioia Tauro’, located north-west of the Reggio Calabria metropolitan area, olive growing extends over 20,000 hectares and the presence of centuries-old olive tree is still widespread. The olive varieties mainly belong to the local cultivars of ‘Sinopolese’ and ‘Ottobratica’, characterized by a remarkable rusticity and high development, perhaps unique in the world; they reach 20–25 meters high, forming what is called a ‘forest of olive trees’. The pruning operations are carried out by means of chainsaws of different power and size whereby, in addition to the previously described difficulties, operators are exposed to prolonged periods of noise levels. The purpose of this study is precisely to assess the exposure of operators to this particular olive grove. The aim is to identify the acoustic levels generated by the two pruning and cross-cutting activities, the risk thresholds and the exposure to which the individual workers of the two work sites are subjected, giving indications on the appropriate safety distances to maintain (according to current regulations) compared to noise sources

    Potential to use Cyperus rotundus in areas of industrial waste disposal

    Get PDF
    A fitorremediação é um processo promissor de descontaminação de solos em que a planta é utilizada como um mecanismo de alocação do agente contaminante e indesejável ao sistema tratado. Plantas de Cyperus rotundus, colhidas em área onde ocorreram descartes de resíduos industriais, foram avaliadas utilizando microscopia óptica (MO) e plasma de argônio indutivamente acoplado (ICP-AES). O trabalho objetivou avaliar as alterações causadas pelos poluentes químicos na estrutura morfológica do corpo epígeo de plantas juvenis de C. rotundus e seu potencial fitorremediador em comparação a plantas colhidas em região não poluída do mesmo solo (testemunha). As alterações anatômicas estruturais identificadas demonstram o potencial efeito poluidor dos contaminantes e também sugerem o comportamento hiperacumulador da planta avaliada.Phytoremediation is a promising process of soil decontamination when the plant is used as a mechanism of allocation of the undesirable contaminant agent in the treated system. Samples of Cyperus rotundus collected in a contaminated area with industrial residues were evaluated through optical microscopy and inductively coupled plasma atomic emission spectroscopy (ICP - AES). This work aimed to evaluate the phytoremediator potential and the morphological alterations in young epigeous body of C. rotundus caused by pollutant chemicals in comparison with plants collected in the same soil with no contamination (witness). The observed anatomic alterations compared with the witnesses demonstrated the potential polluting effect of contaminants and also indicated the hyperaccumulating behavior of the analyzed plants.FAPES

    Photocatalytic performance of palladium and carbon modified TiO2 using solar radiation

    Get PDF
    TiO2 photocatalysts were synthesized by the sol–gel method in the presence of Pd2+ ions and Tween 80. For each material, the effect of the synthesis conditions was studied by its characterization. Photoactivity was evaluated for the selective degradation of phenol (as model pollutant) with Aldrich humic acid (as usual interference) in the reaction mixture, using UV or visible lamps, and under natural sunlight. The materials were able to efficiently degrade phenol, even in the presence of humic acid in the mixture. The solar radiation experiment showed the outstanding photocatalytic activity achieved by TiO2 modified with carbon and palladium: 74 % of phenol degradation (70 % of mineralization, without Pd leaching) after 5 h of exposure.Fil: Rossi, Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Villabrille, Paula Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas "Dr. Jorge J. Ronco". Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Ciencias Aplicadas; ArgentinaFil: Pastrana Martínez, L.M.. Universidad de Granada; EspañaFil: Caregnato, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Rosso, Janina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentin

    Reproducibility of Ablated Volume Measurement Is Higher with Contrast-Enhanced Ultrasound than with B-Mode Ultrasound after Benign Thyroid Nodule Radiofrequency Ablation—A Preliminary Study

    Get PDF
    The reproducibility of contrast-enhanced ultrasound (CEUS) and standard B-mode ultrasound in the assessment of radiofrequency-ablated volume of benign thyroid nodules was compared. A preliminary study was conducted on consecutive patients who underwent radiofrequency ablation (RFA) of benign thyroid nodules between 2014 and 2016, with available CEUS and B-mode post-ablation checks. CEUS and B-mode images were retrospectively evaluated by two radiologists to assess inter- and intra-observer agreement in the assessment of ablated volume (Bland-Altman test). For CEUS, the mean inter-observer difference (95% limits of agreement) was 0.219 mL (-0.372-0.809 mL); for B-mode, the mean difference was 0.880 mL (-1.655-3.414 mL). Reproducibility was significantly higher for CEUS (85%) than for B-mode (27%). Mean intra-observer differences (95% limits of agreement) were 0.013 mL (0.803-4.097 mL) for Reader 1 and 0.031 mL (0.763-3.931 mL) for Reader 2 using CEUS, while they were 0.567 mL (-2.180-4.317 mL, Reader 1) and 0.759 mL (-2.584-4.290 mL, Reader 2) for B-mode. Intra-observer reproducibility was significantly higher for CEUS (96% and 95%, for the two readers) than for B-mode (21% and 23%). In conclusion, CEUS had higher reproducibility and inter- and intra-observer agreement compared to conventional B-mode in the assessment of radiofrequency-ablated volume of benign thyroid nodules

    Non-adiabatic geometrical quantum gates in semiconductor quantum dots

    Get PDF
    In this paper we study the implementation of non-adiabatic geometrical quantum gates with in semiconductor quantum dots. Different quantum information enconding/manipulation schemes exploiting excitonic degrees of freedom are discussed. By means of the Aharanov-Anandan geometrical phase one can avoid the limitations of adiabatic schemes relying on adiabatic Berry phase; fast geometrical quantum gates can be in principle implementedComment: 5 Pages LaTeX, 10 Figures include

    Role of interventional radiology in the management of complications after pancreatic surgery: a pictorial review

    Get PDF
    Pancreatic resections are surgical procedures associated with high incidence of complications, with relevant morbidity and mortality even at high volume centres. A multidisciplinary approach is essential in the management of these events and interventional radiology plays a crucial role in the treatment of patients developing post-surgical complications. This paper offers an overview on the interventional radiological procedures that can be performed to treat different type of complications after pancreatic resection. Procedures such as percutaneous drainage of fluid collections, percutaneous transhepatic biliary procedures, arterial embolisation, venous interventions and fistula embolisation are viable treatment options, with fewer complications compared with re-look surgery, shorter hospital stay and faster recovery. A selection of cases of complications following pancreatic surgery managed with interventional radiological procedure are presented and discussed. Teaching Points \u2022 Interventional radiology is crucial to treat complications after pancreatic surgery \u2022 Percutaneous drainage of collections can be performed under ultrasound or computed tomography guidance \u2022 Percutaneous biliary procedures can be used to treat biliary complications \u2022 Venous procedures can be performed effectively through transhepatic or transjugular access \u2022 Fistulas can be treated effectively by percutaneous embolisation

    Trends in hospitalizations and survival of acute decompensated heart failure in four US communities (2005–2014) ARIC study community surveillance

    Get PDF
    BACKGROUND: Community trends of acute decompensated heart failure (ADHF) in diverse populations may differ by race and sex. METHODS: The ARIC study (Atherosclerosis Risk in Communities) sampled heart failure-related hospitalizations (≥55 years of age) in 4 US communities from 2005 to 2014 using International Classification of Diseases, Ninth Revision, Clinical Modification codes. ADHF hospitalizations were validated by standardized physician review and computer algorithm, yielding 40173 events after accounting for sampling design (unweighted n=8746). RESULTS: Of the ADHF hospitalizations, 50% had reduced ejection fraction, and 39% had preserved EF (HFpEF). HF with reduced ejection fraction was more common in black men and white men, whereas HFpEF was most common in white women. Average age-adjusted rates of ADHF were highest in blacks (38.1 per 1000 black men, 30.5 per 1000 black women), with rates differing by HF type and sex. ADHF rates increased over the 10 years (average annual percentage change: black women +4.3%, black men +3.7%, white women +1.9%, white men +2.6%), mostly reflecting more acute HFpEF. Age-adjusted 28-day and 1-year case fatality proportions were ≈10% and 30%, respectively, similar across race-sex groups and HF types. Only blacks showed decreased 1-year mortality over time (average annual percentage change: black women –5.4%, black men –4.6%), with rates differing by HF type (average annual percentage change: black women HFpEF –7.1%, black men HF with reduced ejection fraction –4.7%). CONCLUSIONS: Between 2005 and 2014, trends in ADHF hospitalizations increased in 4 US communities, primarily driven by acute HFpEF. Survival at 1 year was poor regardless of EF but improved over time for black women and black men

    Spin-based all-optical quantum computation with quantum dots: understanding and suppressing decoherence

    Full text link
    We present an all-optical implementation of quantum computation using semiconductor quantum dots. Quantum memory is represented by the spin of an excess electron stored in each dot. Two-qubit gates are realized by switching on trion-trion interactions between different dots. State selectivity is achieved via conditional laser excitation exploiting Pauli exclusion principle. Read-out is performed via a quantum-jump technique. We analyze the effect on our scheme's performance of the main imperfections present in real quantum dots: exciton decay, hole mixing and phonon decoherence. We introduce an adiabatic gate procedure that allows one to circumvent these effects, and evaluate quantitatively its fidelity
    • …
    corecore