949 research outputs found

    Oxidation reactions are required to produce atranorin from acetate by alginate-immobilized cells of Cladonia verticillaris.

    Get PDF
    Atranorin, a p-depside of the b-orcinol series, is produced by several Cladonia species. Immobilized cells of Cladonia verticillaris in calcium alginate are able to produce atranorin when they are supplied with 1.0 mM acetate as a precursor. Production of the depside is enhanced by adding an oxidant agent (NAD+ or FMN) to the incubation media and its secretion to these media is facilitated by permeabilizing the immobilized cells with 2 % iso-propanol

    Taguchi method application in the pilot production phase-a case study

    Get PDF
    30th International Conference on Flexible Automation and Intelligent Manufacturing (FAIM2021) -15-18 June 2021, Athens, GreeceThis work comes at the product and process development stage in a medical device company, namely the bone substitute. The production of bone substitutes has high regulatory requirements, also the consumer of these products has high-quality requirements. In the pilot production phase, a quality problem was detected in the bone substitute blocks. The work presented was developed in a real context requiring an understanding of the production process and the product. Through a multidisciplinary analysis allowed to direct the problem to the impregnation process. The study of the impregnation process was developed according to the DOE through the Taguchi method. For the experiment, six factors and one interaction allocated in an L8 array were identified. Results obtained show that the process variability is clearly superior to the effect of the studied factors. For future work, the removal of non-significant factors is recommended, adding new factors not included in the study.info:eu-repo/semantics/publishedVersio

    A low-cost platinum film deposited direct on glass substrate for electrochemical counter electrodes

    Get PDF
    AbstractThe preparation and characterization of platinum electrodes on glass substrates obtained by the Pechini method for a potential application as a counter electrode is presented in this paper. This method is based on the dissolution of citric acid (CA) and hexachloride platinum acid (H2PtCl6) in ethylene glycol (EG), and then calcinated in an appropriated temperature to produce the desired metallic film. Characterization was carried out by X-ray diffraction, scanning electron and atomic force microscopy and cyclic voltammetry. X-ray patterns of platinum on glass substrate showed the same features of the platinum bulk metal as well as its voltammetric profile. In order to determine the stability of the electrode, the electrode was subjected to 5000 voltammetric cycles and polarized at constant current of 100 mA cm−2 for at least 200 h, showing no considerable differences compared with the as synthesized electrode. Moreover, the main advantage of the electrode is the low cost (US$ 0.03 cm−2) of the prepared samples

    Investigation of Co(OH)2 formation during cobalt electrodeposition using a chemometric procedure

    Get PDF
    AbstractThe mechanism of Co electrodeposition in sulphate solutions containing boric acid was investigated using the EQCM technique and potentiostatic measurements. The effects of solution composition, temperature and deposition potential were studied using factorial design as a chemometric procedure. The boric acid was used as a buffer to prevent pH changes due to the hydrogen evolution reaction (HER) during electrodeposition. The results showed that Co(OH)2 was formed as a parallel reaction to metallic Co formation under some experimental conditions. The analysis of the factorial design revealed that temperature and [Co2+:H3BO3] molar ratio were the critical variables that affect the mechanism of cobalt electrodeposition. At high temperatures (48°C) and using a 5:1 molar ratio of [Co2+:H3BO3], the formation of cobalt hydroxide was detected simultaneously with cobalt deposition

    Het effect van licht op bio-aardappel vergroening in de retail

    Get PDF
    Uit peilingen van de Nederlandse Aardappel Organisatie en andere, blijkt dat er nog steeds kwaliteitsgebreken vast te stellen zijn bij de biologische aardappels in het schap. Vergroening lijkt één van de belangrijkste aspecten van de kwaliteitsgebreken te zijn. Het doel van dit projectonderdeel is daarom om te onderzoeken welk type licht in de supermarkt leidt tot de beste resultaten om vergroening van bio-aardappels in het schap tegen te gaan

    Food preservative extracts from pumpkin by-products

    Get PDF
    Pumpkin is a vegetable widely consumed around the world, popularly known for its nutritional and pharmacological properties. Some reports in the literature reveal the rich profile of nutrients and bioactive compounds of pumpkin varieties [1,2]. However, the seeds, peels, and fibers resulting from pumpkin processing are still poorly explored by food industry. Considering the alarming scenario of losses and waste during all the food supply chain worldwide [3] and seeking to promote a more sustainable food system, the present study purposed to investigate the by-products of different varieties of pumpkin as a source of extracts with preservative capacity for food application. For that purpose, hydroethanolic extracts from the varieties “Butternut squash”, “Common pumpkin”, and “Kabocha squash” from Portugal, and “Butternut squash”, “Common pumpkin”, and “Musquée de provence” from Algeria, were evaluated in terms of their bioactivities, more specifically the antioxidant, antimicrobial, and cytotoxic capacities. All the samples presented great antioxidant capacity through two based-cell assays, namely the lipid peroxidation inhibition capacity (TBARS) and the anti-hemolytic activity (OxHLIA). Interestingly, the seeds of the common pumpkin from Algeria did not present antihemolytic properties, despite showing the strongest lipid peroxidation inhibition capacity. In fact, the seeds stood out for all the pumpkin varieties in the TBARS assay, while in the OxHLIA assay, the results were quite similar between the type of bioresidues and between the varieties. Moreover, the samples from Portugal showed greater antioxidant capacity than the Algerian ones. Regarding cytotoxicity, the effect of inhibiting non-tumor cell growth was not observed, even at the highest tested concentration of 400 μg/mL. This first validation is of great importance to prevent food safety issues. These preliminary results are the basis for future studies aiming at the valorization of these bioresidues from food industry as a great source of preservative compounds toward the replacement of synthetic additives with natural alternatives allied to health benefits, as also the promotion of a circular economyThe authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional scientific employment program-contract for C. Pereira and L. Barros contracts and A.K. Molina and M.G. Leichtweis PhD grants (2020.06231.BD and 2020.06706.BD, respectively). To FCT, P.I., within the scope of the Project PRIMA Section 2 - Multi-topic 2019: PulpIng (PRIMA/0007/2019).info:eu-repo/semantics/publishedVersio

    Thermal Diffusivity Anisotropy In Calamitic-nematic Lyotropic Liquid Crystal

    Get PDF
    The temperature dependence of the thermal diffusivity of a lyotropic liquid crystal was studied using thermal lens technique. The sample under study was aligned in a magnetic field before measurements thus allowing the determination of the thermal diffusivity in both directions. The results show that the thermal diffusivity sharply decreases in the phase transition temperatures, and presents an anisotropy in the nematic phase.741 II822824Shen, J., Snook, R.D., (1993) J. Appl. Phys., 73, p. 5286Baesso, M.L., Shen, J., Snook, R.D., (1994) J. Appl. Phys., 75, p. 3732Bento, A.C., Palangana, A.J., Evangelista, L.R., Baesso, M.L., Pereira, J.R.D., Da Silva, E.C., Mansanares, A.M., (1996) Appl. Phys. Lett., 68, p. 3371Pereira, J.R.D., Mansanares, A.M., Palangana, A.J., Baesso, M.L., (1999) Mol. Cryst. Liq. Cryst., 332, p. 569Glorieux, C., Bozoki, Z., Fivez, J., Thoen, J., (1995) J. Appl. Phys., 78, p. 3096Mercuri, F., Zammit, U., Marinelli, M., (1998) Phys. Rev. E, 57, p. 596Touloukian, Y.S., Powel, R.W., Ho, C.Y., Nicolau, M.C., (1983) Thermal Properties of Matter, 10. , Plenum, New YorkGarlene, Y., Moarcerou, J.P., (1983) Phys. Rev. Lett., 51, p. 210

    Biochemical approaches on commercial strains of Agaricus subrufescens growing under two environmental cultivation conditions

    Get PDF
    In the present work, the effect of the cultivation process, in the field and under a con- trolled environment, on biochemical parameters by using commercial strains of A. subrufescens were evaluated. The results obtained revealed that the strains cultivated in the field presented higher levels for most of the parameters evaluated (organic acids (20.5–48.0 g/100 g dw), tocopherols (107.0–198.6 μg/100 g dw), and phenolic acids and related compounds (245.2–359.0 μg/100 g dw and 10.6–23.7 μg/100 g dw, respectively)), except for the carbohydrates (53.4–72.6 g/100 g dw), energetic value (373–380 Kcal/100 g dw), and total free sugars (28.8–43.1 g/100 g dw), parameters in which the strains grown in a controlled environment present better results. For both cultivation systems, similar results were obtained regarding saturated, monounsaturated, and polyunsaturated fatty acids, as well as antioxidant and antimicrobial activities. These data contribute to the knowledge and highlight the characterized strains and the cultivation process, which can be used to obtain ingredients with potential applicability as a source of functional compounds.This research was funded by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP no. 19/00419-8 and 2018/21492-2). The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); national funding by FCT, P.I., through the institutional scientific employment program-contract for A.F., C.P. and L.B. contracts. This work is funded by the European Structural and Investment Funds (FEEI) through the Regional Operational Program North 2020, within the scope of Project Mobilizador ValorNatural®.info:eu-repo/semantics/publishedVersio

    Biological activity of pumpkin byproducts: antimicrobial and antioxidant properties

    Get PDF
    Pumpkin fruits are widely appreciated and consumed worldwide. In addition to their balanced nutritional profile, pumpkin species also present valuable bioactive compounds that confer biological and pharmacological properties to them. However, the seeds, peels, and fibrous strands resulting from pumpkin processing are still poorly explored by the food industry. The current study used those fruit components from the genotypes of pumpkin that are economically significant in Portugal and Algeria to produce bioactive extracts. In order to support their usage as preservatives, their phenolic content (HPLC-DAD-ESI/MS) and antioxidant (OxHLIA and TBARS) and antimicrobial properties (against eight bacterial and two fungal strains) were assessed. In terms of phenolic profile, the peel of the Portuguese ‘Common Pumpkin’ showed the most diversified profile and also the highest concentration of total phenolic compounds, with considerable concentrations of (-)-epicatechin. Regarding the antioxidant capacity, the seeds of ‘Butternut Squash’ from both countries stood out, while the fibrous strands of Portuguese ‘Butternut Squash’ and the seeds of Algerian ‘Gold Nugget Pumpkin’ revealed the strongest antimicrobial activity. The bioactive compounds identified in the pumpkin byproducts may validate their enormous potential as a source of bio-based preservatives that may enhance consumers’ health and promote a circular economy.info:eu-repo/semantics/publishedVersio

    mHealth in urology

    Get PDF
    Introduction: Smartphones are increasingly playing a role in healthcare and previous studies assessing medical applications (apps) have raised concerns about lack of expert involvement and low content accuracy. However, there are no such studies in Urology. We reviewed Urology apps with the aim of assessing the level of participation of healthcare professionals (HCP) and scientific Urology associations in their development. Material and Methods: A systematic search was performed on PubMed, Apple's App Store and Google's Play Store, for Urology apps, available in English. Apps were reviewed by three graders to determine the app's platform, target customer, developer, app type, app category, price and the participation of a HCP or a scientific Urology association in the development. Results: The search yielded 372 apps, of which 150 were specific for Urology. A fifth of all apps had no HCP involvement (20.7%) and only a third had been developed with a scientific Urology association (34.7%). The lowest percentage of HCP (13.4%) and urological association (1.9%) involvement was in apps designed for the general population. Furthermore, there was no contribution from an Urology society in "Electronic Medical Record" nor in "Patient Information" apps. A limitation of the study is that only Android and iOS apps were reviewed. Conclusions: Despite the increasing Mobile Health (mHealth) market, this is the first study that demonstrates the lack of expert participation in the design of Urology apps, particularly in apps designed for the general public. Until clear regulation is enforced, the urological community should help regulate app development. Maintaining a register of certified apps or issuing an official scientific seal of approval could improve overall app quality. We propose that urologists become stakeholders in mHealth, shaping future app design and promoting peer-review app validation
    corecore