1,780 research outputs found

    Tameness of the pseudovariety LS1

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    The notion of k-tameness of a pseudovariety was introduced by Almeida and Steinberg and is a strong property which implies decidability of pseudovarieties. In this paper we prove that the pseudovariety LSl, of local semilattices, is k-tame.This work was supported, in part, by FCT through the Centro de Matemática da Universidade do Minho, and by the FCT and POCTI approved project POCTI/32817/MAT/2000 which is comparticipated by the European Community Fund FEDER

    Improved rhamnolipid biosurfactant production by Burkholderia thailandensis E264 using agro-industrial wastes

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    Biosurfactants are amphiphilic surface-active compounds, produced by various microorganisms, that reduce surface and interfacial tension. These compounds are attracting increasing interest over their chemical counterparts due to their advantages, such as biodegradability, high stability in extreme environments, low toxicity, low critical micelle concentrations (CMC) and the fact that they can be effectively produced from agro-industrial wastes and renewable resources. Furthermore, their diversity allows for a significant number of uses, including microbial enhanced oil recovery (MEOR), bioremediation and biomedical applications. However, the high operational costs, mainly regarding the use of expensive raw materials in the fermentation and the complex downstream processing due to the low production yields restricts their industrial-scale applications. Several attempts to solve these limitations by reducing the production costs have been conducted and include the use of low-cost agro-industrial wastes and by-products as substrates. One of these low-cost substrates, that has been successfully used to produce biosurfactants by Bacillus subtilis and Pseudomonas aeruginosa, is corn steep liquor (CSL). In this work, CSL is evaluated for rhamnolipid biosurfactant production by Burkholderia thailandensis E264. When grown in a culture medium containing CSL (7.5% v/v) as sole substrate, this strain produced 1.8 g rhamnolipid/L, which is about 2.6 times the amount of rhamnolipid produced in the standard synthetic medium. By supplementing the culture medium with olive oil mill wastewater (OMW, 10% v/v), a residue originating from the olive oil extraction industry, rhamnolipid production was increased up to 2.6 g/L, most likely due to the inductive effect of long-chain fatty acids present in OMW (mainly oleic, palmitic, linoleic and stearic acids) on rhamnolipid production. Rhamnolipids purification was also done and the biosurfactant produced in the low-cost medium (CSL + OMW) exhibited better surface-active properties when compared with those produced in the synthetic medium, reducing the surface tension of water to 26.8 ± 0.1 mN/m, with a CMC of 280 mg/L (28.8 ± 0.2 mN/m and 460 mg/L, respectively, in the synthetic medium). These results demonstrate that rhamnolipid production is more efficient in the low-cost medium. Furthermore, to the best of the authors knowledge, this is the first experimental research that describes the utilization of CSL and CSL + OMW as substrates for the production of rhamnolipids by B. thailandensis, with very optimistic results in terms of cost and production levels.This work was sponsored by PARTEX Oil and Gas and it was supported by the Portuguese Foundation for Science and Technology(FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

    The synthetic cannabinoids phenomenon: from structure to toxicological properties. A review

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    The word “cannabinoid” refers to every chemical substance, regardless of structure or origin, that joins the cannabinoid receptors of the body and brain and that have similar effects to those produced by the Cannabis plant and based on their source of production, cannabinoids can be classified into endocannabinoids, phytocannabinoids and synthetic cannabinoids. Synthetic cannabinoids represent the largest class of drugs detected through the EU Early Warning System with a total of 190 substances notified from 2008 to 2018 and about 280 have been reported worldwide to the United Nations Office on Drugs and Crime. Sprayed on natural herb mixtures with the aim to mimic the euphoria effect of cannabis and sold as “herbal smoking blends” or “herbal incense” under brand names like “Spice” or “K2”, synthetic cannabinoids are available from websites for the combination with herbal materials or more recently, for the use in e-cigarettes. Currently labeled as “not for human consumption” to circum vent legislation, their legal status varies by country with many government institutions currently push ing for their control. However, due to the emergence of new substances, it requires a constant update of the list of controlled drugs. Little is known about how these substances work and their toxic effects in humans and the same product could vary not only in the amount and in the type of substance added. In the last years, synthetic cannabinoids have been associated with deaths and acute intoxica tions in Europe and, despite a range of new measures introduced in this area, continue to represent a challenge to current drug policy models. These synthetic substances are much more potent than nat ural cannabis, as well as displayed greater efficacy, acting as full agonists at the cannabinoid receptors. It is possible that, along with being highly potent, some may also have long half-lives, potentially lead ing to a prolonged psychoactive effect. The present work provides a review on existing literature about the development of synthetic cannabinoids as substances of abuse, current patterns of abuse and their legal status, chemical classification, and some pharmacological and toxicological properties.info:eu-repo/semantics/publishedVersio

    A LINEAR STUDY OF HIGH-DRAG STATES AND FLOW STAGNATION PRODUCED BY MOUNTAIN WAVES

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    A linear model of gravity waves generated by stratified airflow over mountains is developed. The model provides simple, closed-form formulas for the surface drag in a situation where conditions for wave resonance exist. The wind is constant near the surface and decreases linearly above. The drag normalized by its value in the absence of shear is found to depend on two parameters: the height of the interface where the shear is discontinuous and the Richardson number, Ri, in the region above. This drag attains maxima when the height of the interface induces constructive interference between the upward and downward propagating reflected waves, and minima when there is destructive interference. The amplitude of the drag modulation becomes larger for lower Ri. It is also shown that, for Ri<2.25, the locations where wave breaking is first predicted to occur in flow over a 2D ridge become displaced horizontally and vertically by an amount depending on Ri

    Simulation of non-radiative energy transfer in photosynthetic systems using a quantum computer

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    Photosynthesis is an important and complex physical process in nature, whose comprehensive understanding would have many relevant industrial applications, for instance in the field of energy production. In this paper we propose a quantum algorithm for the simulation of the excitonic transport of energy, occurring in the first stage of the process of photosynthesis. The algorithm takes in account the quantum and environmental effects (pure-dephasing), influencing the quantum transport. We performed quantum simulations of such phenomena, for a proof of concept scenario, in an actual quantum computer the IBM Q, of 5 qubits. We validate the results with the Haken-Str\"obl model and discuss the influence of environmental parameters on the efficiency of the energy transport.POCI-01-0145-FEDER-03094

    Sepsis during pregnancy: case report

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    BACKGROUND AND OBJECTIVES: Sepsis during pregnancy is a rare complication. This potentially fatal disease often occurs due to maternal infectious and can lead to fetal loss. Therefore, any attempted treatment must be aimed at the mother s well being. As a matter of fact, there are few recent medical publications about sepsis in pregnancy. In spite of this, the treatment based on Surviving Sepsis Campaign seems suitable and practical. The aim of this article is making a case report highlighting a very well succeeded treatment of a pregnant woman with urinary sepsis. CASE REPORT: A 22 year old in her 27th week of pregnancy is hospitalized with pyelonefhritis. One day later, she begins presenting signs of sepsis and unresponsive hypoxemia, resulting in intubation. Afterwards, she evolved with persistent low blood pressure that was unresponsive to volume expansion and had to be put on vasopressor medication. She received intensive care support based on Surviving Sepsis Campaign. The patient evolved with an important improvement of her ventilatory stats and was extubated. After completing antibiotic treatment, she was discharged and delivered a healthy baby after 42 weeks pregnancy. CONCLUSIONS: Sepsis in pregnancy is a rare and potentially fatal complication. The main treatment is based on Surviving Sepsis Campaign. The patient had an outstanding improvement and overcame her condition after intensive care support.JUSTIFICATIVA E OBJETIVOS: A sepse durante a gestação é uma complicação rara. O comprometimento fetal resulta principalmente da descompensação materna, por conseguinte, o tratamento deve ser direcionado ao bem-estar da mãe. Poucas evidências permitem extrapolar o tratamento de pacientes não gestantes para as gestantes, porém, o tratamento baseado no Surviving Sepsis Campaing parece adequado e prático. O objetivo deste estudo foi rever o tratamento da sepse na gestação e relatar um caso de gestante com sepse grave que evoluiu favoravelmente. RELATO DO CASO: Paciente com 22 anos, primigesta, na 27ª semana de gestação foi internada com diagnóstico de pielonefrite aguda. Um dia após a internação apresentou quadro de sepse, com hipoxemia refratária às medidas não-invasivas necessitando de intubação traqueal. Após a intubação evoluiu com hipotensão refratária à expansão volêmica necessitando de fármaco vasoativo. Foi interrompido o uso de noradrenalina no mesmo dia e prescrito cefepima. Evoluiu com importante melhora dos padrões ventilatórios, sendo extubada e recebeu alta hospitalar logo após completar o tratamento com antibiótico. Ao completar a 42ª semana de gestação foi internada para indução do trabalho de parto, sendo realizado parto vaginal, sem intercorrências. CONCLUSÕES: A sepse na gestação, mesmo sendo rara é potencialmente fatal. O tratamento foi baseado no Surviving Sepsis Campaign e a paciente apresentou melhora significativa dos parâmetros de perfusão nas primeiras horas com ótima evolução, apesar da gravidade da doença.UNIFESP Clínica Médica da EPMUNIFESP Pronto Socorro da EPM Unidade de Terapia IntensivaUNIFESP, Clínica Médica da EPMUNIFESP, Pronto Socorro da EPM Unidade de Terapia IntensivaSciEL

    OPTEXPLOR – new application for water resources management for private water supply utilities

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    This article presents the steps made for the development of a new water management system (WMS) for a private water utility in the south of Portugal, and its main results. The WMS is composed of a set of models representing the water resources, surface and groundwater, water quality models, economic models, and water allocation optimization models. The system was developed at the request of the regional water utility (Águas do Algarve, S.A.), which is responsible for distributing water to the entire Algarve region (most touristic area in Portugal, with about ten million tourists per year, and a local population of about four hundred thousand). Results clearly show that independently of the amount of water available, inter-annual exploration is always the best solution, if possible. When water scarcity is high, as in consecutive dry years, the water utility will need to call municipalities to use their systems to complement supply. The level of supply deficit is higher, in any case, for annual exploration management, and so are exploration costs. These results clearly show that water resources management needs careful inter-annual planning, even for a private water supply utility with very limited control over water exploration by other competing users

    Leptomonas seymouri and Crithidia fasciculata exoantigens can discriminate human cases of visceral leishmaniasis from American tegumentary leishmaniasis ones

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    Exoantigens (exo) from Leptomonas seymouri and Crithidia fasciculata were used in an enzyme linked immunosorbent assay (ELISA), showing 100% reactivity with sera from visceral leishmaniasis (VL) cases, and no reactivity with American tegumentary leishmaniasis (ATL) ones. Our results have indicated that these exoantigens can be applied in the discrimination of VL and ATL cases

    Application of image analysis to the monitoring of fermentation

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