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1.
Biochim Biophys Acta Biomembr ; 1866(7): 184364, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38901662

ABSTRACT

The combined application of electric fields and ultrasonic waves has shown promise in controlling cell membrane permeability, potentially resulting in synergistic effects that can be explored in the biotechnology industry. However, further clarification on how these processes interact is still needed. The objective of the present study was to investigate the atomic-scale effects of these processes on a DPPC lipid bilayer using molecular dynamics simulations. For higher electric fields, capable of independently forming pores, the application of an ultrasonic wave in the absence of cavitation yielded no additional effects on pore formation. However, for lower electric fields, the reduction in bilayer thickness induced by the shock wave catalyzed the electroporation process, effectively shortening the mean path that water molecules must traverse to form pores. When cavitation was considered, synergistic effects were evident only if the wave alone was able to generate pores through the formation of a water nanojet. In these cases, sonoporation acted as a mean to focus the electroporation effects on the initial pore formed by the nanojet. This study contributes to a better understanding of the synergy between electric fields and ultrasonic waves and to an optimal selection of processing parameters in practical applications of these processes.


Subject(s)
Electroporation , Lipid Bilayers , Molecular Dynamics Simulation , Ultrasonic Waves , Lipid Bilayers/chemistry , Electroporation/methods , Electricity , Cell Membrane Permeability , 1,2-Dipalmitoylphosphatidylcholine/chemistry
2.
Bioresour Technol ; 394: 130234, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38142906

ABSTRACT

A new alternative for hydrodynamic cavitation-assisted pretreatment of sugarcane bagasse was proposed, along with a simultaneous saccharification and co-fermentation (SSCF) process performed in interconnected columns. Influential variables in the pretreatment were evaluated using a statistical design, indicating that an ozone flow rate of 10 mg min-1 and a pH of 5.10 resulted in 86 % and 72 % glucan and xylan hydrolysis yields, respectively, in the subsequent enzymatic hydrolysis process. Under these optimized conditions, iron sulfate (15 mg L-1) was added to assess Fenton pretreatment, resulting in glucan and xylan hydrolysis yields of 92 % and 71 %, respectively, in a material pretreated for 10 min. In SSCF, ethanol volumetric productivities of 0.33 g L-1 h-1 and of 0.54 g L-1 h-1 were obtained in batch and fed-batch operation modes, achieving 26 g L-1 of ethanol in 48 h in the latter mode.


Subject(s)
Cellulose , Saccharomycetales , Saccharum , Cellulose/metabolism , Fermentation , Saccharum/metabolism , Ethanol , Hydrodynamics , Cells, Immobilized/metabolism , Xylans , Hydrolysis
3.
Article in English | MEDLINE | ID: mdl-37737947

ABSTRACT

Nowadays, the presence of persistent dissolved pollutants in water has received increasing attention due to their toxic effects on living organisms. Considering the limitations of conventional wastewater treatment processes for the degradation of these compounds, advanced oxidation processes such as electro-Fenton and sono-chemical process, as well as their combination, appear as potentially effective options for the treatment of wastewater contaminated with bio-recalcitrant pollutants. In view of the importance of the development of processes using real effluents, this review aims to provide a comprehensive perspective of sono-electro-Fenton-related processes applied for real wastewater treatment. In the first section, the fundamentals and effectiveness of both homogeneous and heterogeneous electro-Fenton approaches for the treatment of real wastewater are presented. While the second part of this work describes the fundamentals of ultrasound-based processes, the last section focuses on the coupling of the two methods for real wastewater treatment and on the effect of the main operational parameters of the process. On the basis of the information presented, it is suggested that sono-electro-Fenton processes substantially increase the efficiency of the treatment as well as the biodegradability of the treated wastewater. The combined effect results from mass transfer improvement, electrode cleaning and activation, water electrolysis, and the electro-Fenton-induced production of hydroxyl radicals. The information presented in this work is expected to be useful for closing the gap between laboratory-scale assays and the development of novel wastewater technologies.

4.
Foods ; 12(12)2023 Jun 16.
Article in English | MEDLINE | ID: mdl-37372601

ABSTRACT

Meat is an important part of the food pyramid in Mexico, to such an extent that it is included in the basic food basket. In recent years, there has been great interest in the application of so-called emerging technologies, such as high-intensity ultrasound (HIU), to modify the characteristics of meat and meat products. The advantages of the HIU in meat such as pH, increased water-holding capacity, and antimicrobial activity are well documented and conclusive. However, in terms of meat tenderization, the results are confusing and contradictory, mainly when they focus on three HIU parameters: acoustic intensity, frequency, and application time. This study explores via a texturometer the effect of HIU-generated acoustic cavitation and ultrasonoporation in beef (m. Longissimus dorsi). Loin-steak was ultrasonicated with the following parameters: time tHIU = 30 min/each side; frequency fHIU = 37 kHz; acoustic intensity IHIU = ~6, 7, 16, 28, and 90 W/cm2. The results showed that acoustic cavitation has a chaotic effect on the loin-steak surface and thickness of the rib-eye due to Bjerknes force, generating shear stress waves, and acoustic radiation transmittance via the internal structure of the meat and the modification of the myofibrils, in addition to the collateral effect in which the collagen and pH generated ultrasonoporation. This means that HIU can be beneficial for the tenderization of meat.

5.
Ultrason Sonochem ; 95: 106388, 2023 May.
Article in English | MEDLINE | ID: mdl-37011519

ABSTRACT

In this study, a novel hydrodynamic cavitation unit combined with a glow plasma discharge system (HC-GPD) was proposed for the degradation of pharmaceutical compounds in drinking water. Metronidazole (MNZ), a commonly used broad-spectrum antibiotic, was selected to demonstrate the potential of the proposed system. Cavitation bubbles generated by hydrodynamic cavitation (HC) can provide a pathway for charge conduction during glow plasma discharge (GPD). The synergistic effect between HC and GPD promotes the production of hydroxyl radicals, emission of UV light, and shock waves for MNZ degradation. Sonochemical dosimetry provided information on the enhanced formation of hydroxyl radicals during glow plasma discharge compared to hydrodynamic cavitation alone. Experimental results showed a MNZ degradation of 14% in 15 min for the HC alone (solution initially containing 300 × 10-6 mol L-1 MNZ). In experiments with the HC-GPD system, MNZ degradation of 90% in 15 min was detected. No significant differences were observed in MNZ degradation in acidic and alkaline solutions. MNZ degradation was also studied in the presence of inorganic anions. Experimental results showed that the system is suitable for the treatment of solutions with conductivity up to 1500 × 10-6 S cm-1. The results of sonochemical dosimetry showed the formation of oxidant species of 0.15 × 10-3 mol H2O2 L-1 in the HC system after 15 min. For the HC-GPD system, the concentration of oxidant species after 15 min reached 13 × 10-3 molH2O2L-1. Based on these results, the potential of combining HC and GPD systems for water treatment was demonstrated. The present work provided useful information on the synergistic effect between hydrodynamic cavitation and glow plasma discharge and their application for the degradation of antibiotics in drinking water.


Subject(s)
Drinking Water , Metronidazole , Metronidazole/chemistry , Hydrogen Peroxide/chemistry , Hydrodynamics , Anti-Bacterial Agents , Oxidants
6.
Am J Bot ; 110(4): e16146, 2023 04.
Article in English | MEDLINE | ID: mdl-36826405

ABSTRACT

PREMISE: Understanding tree species' responses to drought is critical for predicting the future of tropical forests, especially in regions where the climate is changing rapidly. METHODS: We compared anatomical and functional traits of the dominant tree species of two tropical forests in southern Amazonia, one on deep, well-drained soils (cerradão [CD]) and one in a riparian environment (gallery forest [GF]), to examine potential anatomical indicators of resistance or vulnerability to drought. RESULTS: Leaves of CD species generally had a thicker cuticle, upper epidermis, and mesophyll than those of GF species, traits that are indicative of adaptation to water deficit. In the GF, the theoretical hydraulic conductivity of the stems was significantly higher, indicating lower investment in drought resistance. The anatomical functional traits of CD species indicate a greater potential for surviving water restriction compared to the GF. Even so, it is possible that CD species could also be affected by extreme climate changes due to the more water-limited environment. CONCLUSIONS: In addition to the marked anatomical and functional differences between these phytophysiognomies, tree diversity within each is associated with a large range of hydraulic morphofunctional niches. Our results suggest the strong potential for floristic and functional compositional shifts under continued climate change, especially in the GF.


Subject(s)
Trees , Water , Trees/physiology , Water/physiology , Tropical Climate , Forests , Droughts , Plant Leaves/physiology
7.
Foods ; 12(3)2023 Jan 19.
Article in English | MEDLINE | ID: mdl-36766002

ABSTRACT

In this study, we evaluate the most recently applied emerging non-thermal technologies (NTT) to improve meat tenderization, high-intensity ultrasound (HIUS), and high-pressure processing (HPP), aiming to understand if individual effects are beneficial and how extrinsic and intrinsic factors influence meat toughness. We performed a systematic literature search and meta-analysis in four databases (Web of Science, Scopus, Embase, and PubMed). Among the recovered articles (n = 192), 59 studies were included. We found better sonication time in the range of 2-20 min. Muscle composition significantly influences HIUS effects, being type IIb fiber muscles more difficult to tenderize (p < 0.05). HPP effects are beneficial to tenderization at 200-250 MPa and 15-20 min, being lower and higher conditions considered inconclusive, tending to tenderization. Despite these results, undesirable physicochemical, microstructural, and sensory alterations are still unknown or represent barriers against applying NTT at the industrial level. Optimization studies and more robust analyses are suggested to enable its future implementation. Moreover, combining NTT with plant enzymes demonstrates an interesting alternative to improve the tenderization effect caused by NTT. Therefore, HIUS and HPP are promising technologies for tenderization and should be optimized considering time, intensity, pressure, muscle composition, undesirable changes, and combination with other methods.

8.
Acta Vet. Brasilica ; 17(2): 91-98, 2023. ilus, tab, graf
Article in English | VETINDEX | ID: biblio-1513109

ABSTRACT

The objective of this work was to evaluate the use of an ultrafine bubble generator of own manufacture for oxygenation of Nile tilapia (Oreochromis niloticus) breeding tanks in a recirculating water system. The research was divided into two steps: 1) oxygen saturation test; 2) application of ultrafine bubble production technology for the breeding of Nile tilapia. In the first step, the water of a 2.0 m3 test tank was completely deoxygenated and the ultrafine bubble generator was turned on for 60 min. In the second step, the generator was connected to the water recirculating system for breeding of Nile tilapia to compare the overall performance of this system with other under conventional aeration system. The ultrafine bubble generator could reach 100% oxygen saturation in the test tank (27.8 °C) in approximately 21 min and, at the end of 60 min, the concentration was 21.8 mg L-1 (277.52% saturation). The results showed significant difference (p<0.05) between the mean dissolved oxygen concentration in the treatment with ultrafine bubbles (9.80 ±3.68 mg L-1) and the treatment with conventional aeration (3.47 ± 0.88 mg L-1). No significant difference (p>0.05) was found for the zootechnical performance parameters evaluated. The conclusion was that the ultrafine bubble generator is more efficient to maintain a high dissolved oxygen concentration in the recirculating water in Nile tilapia breeding tanks than the conventional aeration system


O objetivo da presente pesquisa foi avaliar a utilização do gerador de bolhas ultrafinas (fabricação própria) para oxigenação de tanques de criação de tilápia do Nilo em sistema de recirculação de água. A pesquisa foi dividida em duas etapas: 1) teste de saturação de oxigênio; 2) aplicação da tecnologia de produção de bolhas ultrafinas na criação da tilápia do Nilo. Na primeira, a água de um tanque teste (2,0 m³) foi completamente desoxigenada e o gerador de bolhas ultrafinas acionado por um período de 60 min. Na segunda, o gerador foi ligado a um sistema de recirculação para criação de tilápia para comparar o desempenho geral desse sistema ao de outro no qual utilizou-se aeração convencional. O gerador de bolhas ultrafinas foi capaz de atingir 100% de saturação de oxigênio no tanque teste (27,8 °C) em aproximadamente 21 min e, ao final de 60 min, a concentração foi 21,8 mg/L (saturação 277,52%). Foi observada diferença significativa (p<0,05) entre a concentração média de oxigênio dissolvido no tratamento com bolhas ultrafinas (9,80 ± 3,68 mg/L) e o tratamento com aeração convencional (3,47 ± 0,88 mg/L). Não foi observada diferença significativa (p>0,05) para nenhum dos parâmetros de desempenho zootécnico avaliados. Pode-se concluir que o gerador de bolhas ultrafinas é mais eficiente em manter alta a concentração de oxigênio dissolvido em tanques de criação de tilápia em sistema de recirculação de água quando comparado ao sistema convencional de aeração


Subject(s)
Animals , Aeration/methods , Water Recirculation , Oxygenation , Cichlids/physiology , Fisheries
9.
Sci. agric ; 80: e20220224, 2023. graf
Article in English | VETINDEX | ID: biblio-1450487

ABSTRACT

Most commercial apple orchards are established on either Marubakaido (Malus prunifolia Borkh.) (high vigor), M-9 (Malus pumila) (low vigor), or a combination of both rootstocks through the intergrafting technique. The Geneva® Series rootstocks were developed as an alternative to orchards modernization. The vigor of rootstocks influences the anatomical xylem formation and, therefore, the canopy cultivar's hydraulic conductivity. When affected by embolism, hydraulic conductivity harms plant metabolism, reducing crop yield and fruit quality. This study aimed to evaluate four Geneva® Series rootstocks with potential use in southern Brazil, in terms of hydraulic conductivity (K) and percentage loss of conductance (PLC), during the winter period in two different years. The G.213 rootstock presented the best performance for the variables analyzed; however, higher values of xylem functionality loss were observed in G.814.


Subject(s)
Malus , Water Discharge
10.
Environ Technol ; : 1-13, 2022 Dec 12.
Article in English | MEDLINE | ID: mdl-36508608

ABSTRACT

Dissolved Air Flotation (DAF) systems are designed to remove oil and grease (O&G) and total suspended solids (TSS) in wastewater treatment. These systems require saturation tanks, water pumps, and high-pressure compressors to control the pressure, hydraulic retention time, and airflow parameters. DAF process efficiency depends on complex operational controls associated with these components, and the most critical aspect of an effectively operating DAF unit is a generated bubble size. This work presents the design and operational test of a flotation unit prototype that replaces the saturation tank and high-pressure compressors present in DAF with the CARMIN microbubble injector, the evaluation of the proposed system's TSS and O&G removal efficiency was carried out considering different initial configurations of the injector to change the generated microbubble size, four synthetic wastewater solutions, and poly aluminum chloride as a flocculant to establish the potential of this system for the poultry processing wastewater treatment. Mean microbubble size results were obtained from 47.41 µm to 116.17 µm. The average removal efficiency of TSS exceeded 65% under a high concentration of suspended particles (1,560 mg/l) and 80% under a lower TSS concentration (795 mg/l). Meanwhile, 70% and 90% of O&G were removed from high (400 mg/l) and low (100 mg/l) initial O&G concentrations, respectively. These removal levels are similar to those reported in the literature for DAF for poultry processing wastewater, albeit with a simple configuration and better controllability and scalability.

11.
J Fungi (Basel) ; 8(11)2022 Oct 24.
Article in English | MEDLINE | ID: mdl-36354884

ABSTRACT

Shock waves, as used in medicine, can induce cell permeabilization, genetically transforming filamentous fungi; however, little is known on the interaction of shock waves with the cell wall. Because of this, the selection of parameters has been empirical. We studied the influence of shock waves on the germination of Aspergillus niger, to understand their effect on the modulation of four genes related to the growth of conidia. Parameters were varied in the range reported in protocols for genetic transformation. Vials containing conidia in suspension were exposed to either 50, 100 or 200 single-pulse or tandem shock waves, with different peak pressures (approximately 42, 66 and 83 MPa). In the tandem mode, three delays were tested. To equalize the total energy, the number of tandem "events" was halved compared to the number of single-pulse shock waves. Our results demonstrate that shock waves do not generate severe cellular effects on the viability and germination of A. niger conidia. Nevertheless, increase in the aggressiveness of the treatment induced a modification in four tested genes. Scanning electron microscopy revealed significant changes to the cell wall of the conidia. Under optimized conditions, shock waves could be used for several biotechnological applications, surpassing conventional techniques.

12.
Front Plant Sci ; 13: 974050, 2022.
Article in English | MEDLINE | ID: mdl-36092408

ABSTRACT

The search for drought tolerant species or cultivars is important to address water scarcity caused by climate change in Mediterranean regions. The anisohydric-isohydric behavior concept has been widely used to describe stomatal regulation during drought, simply in terms of variation of minimal water potential (Ψmin) in relation to pre-dawn water potential (Ψpd). However, its simplicity has sometimes failed to deliver consistent results in describing a complex behavior that results from the coordination of several plant functional traits. While Prunus dulcis (almond) is known as a drought tolerant species, little information is available regarding consistent metrics to discriminate among cultivars or the mechanisms underlying drought tolerance in almond. Here we show a sequence of plant stomatal, hydraulic, and wilting responses to drought in almonds, and the main differences between anisohydric and isohydric cultivars. In a pot desiccation experiment we observed that stomatal closure in P. dulcis is not driven by loss in turgor or onset of xylem cavitation, but instead, occurs early in response to decreasing Ψmin that could be related to the protection of the integrity of the hydraulic system, independently of cultivar. Also, we report that anisohydric cultivars of P. dulcis are characterized by maximum stomatal conductance, lower water potentials for stomatal closure and turgor loss, and lower vulnerability to xylem cavitation, which are traits that correlated with metrics to discriminate anisohydric and isohydric behavior. Our results demonstrate that P. dulcis presents a strategy to avoid cavitation by closing stomata during the early stages of drought. Future research should also focus on below-ground hydraulic traits, which could trigger stomatal closure in almond.

13.
Ultrason Sonochem ; 89: 106144, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36058139

ABSTRACT

Red-G dye is one of the main dyes used in the textile industry to dye alpaca wool. Therefore, considering the large volume of processed wool in Perú, the development of efficient technologies for its removal is a present scientific issue. In this study, an integrated system based on hydrodynamic cavitation (HC) and photo-Fenton process was evaluated to remove the Red-G dye. Using a hybrid cavitation device (venturi + orifice plate), the effect of pH was evaluated, achieving 21 % of removal at pH 2 which was more than 80 % higher compared to pH 4 and 6. The effect of temperature was also evaluated in HC-system at pH 2, where percentage of dye degradation increased at lower temperatures (around 20 °C). Then, 50.7 % of dye was removed under optimized condition of HC-assisted Fenton process (FeSO4:H2O2 of 1:30), that value was improved strongly by UV-light incorporation in the HC-system, increasing to 99 % removal efficiency with respect to HC-assisted Fenton process and reducing the time to 15 min. Finally, the developed cavitation device in combination with photo-Fenton process removed efficiently the dye and thus could be considered an interesting option for application to real wastewater.


Subject(s)
Camelids, New World , Wastewater , Animals , Coloring Agents , Hydrodynamics , Hydrogen Peroxide , Wool
14.
Heliyon ; 8(3): e09019, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35252616

ABSTRACT

Hydrodynamic cavitation is a new technology used for the treatment of wastewater. Landfill leachates contain a large variety of organic pollutants and inorganic matter, with recalcitrant and bio-refractory compounds. The present study was designed to evaluate the effect of hydrodynamic cavitation on landfill leachate quality indices. Three experimental designs were proposed. First, the influence of collection climate on leachate quality characteristics was analyzed. Second, the best cavitation time was chosen, which promoted the greatest reduction in the effluent pollutant load. Finally, the hydrogen peroxide (H2O2) concentration was evaluated as an adjuvant in the cavitation process. A model TEKMASH TEK-1SL equipment was used. This cavitation unit operated with a flow rate of 30 m3 h-1, a temperature of 75 °C, and an inlet pressure of 3 bar. The cavitation chamber was of the annular flow type. The statistical analyses were run through ANOVA and Tukey's test, with significance α = 0.05. The response variables for the factors were biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total organic carbon (TOC) and total suspended solids (TSS). An influence of the climatic condition on the leachate quality parameters was found, and the difference was marked in COD. In all cases, both for the cavitation process and for the cavitation-oxidant scheme, there was a reduction of 23%-51% BOD5, 30%-53% COD, 12%-21% TOC and 100% removal in TSS. In a 30-minute treatment, the highest COD removal percentage was reached, corresponding to 53.20%. Furthermore, a 200 ppm concentration of hydrogen peroxide enhanced the reduction of BOD5 and COD with proportions of 51.55% and 38.21%, respectively. Hydrodynamic cavitation offers advantages in the treatment of wastewater and can be used as an independent technique or as a hybrid method.

15.
Curr Res Food Sci ; 5: 345-350, 2022.
Article in English | MEDLINE | ID: mdl-35198993

ABSTRACT

A wide variety of by-products are produced by the industry when animals are slaughtered. However, the proteins present in these by-products, are not being fully useable, in the elaboration of value-added products. Staphylococcus xylosus is commonly used as a starter culture in meat products subjected to ripening for a long period, as it produces proteolytic and lipolytic enzymes that improve the sensory quality of the products. Ultrasound (US) has been arousing interest in the meat industry, as it reduces processing time and also improves the technological and sensory quality of meat products. However, the stimulate effect of US on the growth of S. xylosus in by-products from the poultry industry is still unknown. Thus, this study aimed to evaluate the stimulate effect of US on the growth of S. xylosus inoculated in by-products from the poultry industry. S. xylosus was inoculated (5.63 log CFU/g) in sterilized by-products from the poultry, which were then sonicated at 37 °C for 0, 15, 30, and 45 min according to the following parameters: frequencies of 130 and 35 kHz, amplitudes of 50% and 80% and normal and degas operating modes. The sonicated samples were incubated at 37 °C for 0, 24, 48, and 72 h. Soon after sonication, no stimulate effect of US was observed on the growth of S. xylosus. However, after 24 h of incubation, the samples sonicated for 15 and 30 min in normal mode, at 35 and 130 kHz, and amplitudes of 50 and 80% exhibited better stimulate effect at the growth S. xylosus counts (p < 0.01) when compared to the Control, with values of 8.23 and 7.77 log CFU/g, respectively. These results can be exploited to obtain new added-value products, having as raw material by-products from the poultry industry.

16.
HCA Healthc J Med ; 3(4): 253-256, 2022.
Article in English | MEDLINE | ID: mdl-37426868

ABSTRACT

Description Lung cavitation as a complication of COVID-19 is rare. A 56-year-old male presented with lung cavitation, small volume hemoptysis, and violaceous discoloration of the right great toe, 5 weeks after diagnosis with COVID-19 pneumonia. The digital changes were consistent with previously described microvascular changes called "COVID toe." CT angiography of the chest was negative for pulmonary embolism but showed a 2.5 x 3.1 x 2.2 cm cavitation within the right lung. Extensive evaluation for commonly implicated infectious and autoimmune causes was negative. We concluded that the cavitary lung lesions were likely a complication of COVID-19 pneumonia and may implicate microangiopathy as an important component of pathogenesis. This case highlights a rare complication of COVID-19 of which clinicians should be aware.

17.
Bioresour Technol ; 345: 126458, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34863850

ABSTRACT

Environmental problems due to utilization of fossil-derived materials for energy and chemical generation has prompted the use of renewable alternative sources, such as lignocellulose biomass (LB). Indeed, the production of biomolecules and biofuels from LB is among the most important current research topics aiming to development a sustainable bioeconomy. Yet, the industrial use of LB is limited by the recalcitrance of biomass, which impairs the hydrolysis of the carbohydrate fractions. Hydrodynamic cavitation (HC) and Advanced Oxidative Processes (AOPs) has been proposed as innovative pretreatment strategies aiming to reduce process time and chemical inputs. Therefore, the underlying mechanisms, procedural strategies, influence on biomass structure, and research gaps were critically discussed in this review. The performed discussion can contribute to future developments, giving a wide overview of the main involved aspects.


Subject(s)
Hydrodynamics , Lignin , Biofuels , Biomass , Lignin/metabolism , Oxidative Stress
18.
Bioresour Bioprocess ; 9(1): 7, 2022 Jan 25.
Article in English | MEDLINE | ID: mdl-38647820

ABSTRACT

The hydrodynamic cavitation comes out as a promising route to lignocellulosic biomass pretreatment releasing huge amounts of energy and inducing physical and chemical transformations, which favor lignin-carbohydrate matrix disruption. The hydrodynamic cavitation process combined with other pretreatment processes has shown an attractive alternative with high pretreatment efficiency, low energy consumption, and easy setup for large-scale applications compared to conventional pretreatment methods. This present review includes an overview of this promising technology and a detailed discussion on the process of parameters that affect the phenomena and future perspectives of development of this area.

19.
São José dos Campos; s.n; 2022. 48 p. tab, ilus.
Thesis in Portuguese | BBO - Dentistry | ID: biblio-1397956

ABSTRACT

A busca pela otimização dos resultados clínicos, levou ao desenvolvimento de novas tecnologias. O Sistema Piezoelétrico Odontológico (SPO), tem sido cada vez mais difundido e sua principal característica é o fenômeno da cavitação, que é o processo de vaporização, geração de bolhas e sua implosão subsequente. Tais fenômenos acústicos estão diretamente relacionados a lise das membranas celulares dos MO. O objetivo deste estudo foi investigar o fenômeno da cavitação do sistema piezoelétrico, em diferentes potências de ativação, em relação ao efeito antimicrobiano sobre Candida albicans. Para a execução do trabalho, foi utilizado o aparelho DENTSURG. Foi utilizada a cepa padrão de Candida albicans (18060), mantidas em freezer a -80ºC no Laboratório de Microbiologia e Imunologia do ICT UNESP. Para ativação de Candida albicans a cepa foi cultivada em ágar Sabouraud com cloranfenicol e incubada em estufa por 24 horas a 37°C. Após preparo dos MO, 100µL das células padronizadas foram adicionadas em placas de 24 poços e após essa etapa, um único operador treinado realizou a ativação, com os diferentes protocolos de ativação. Posteriormente, foram realizadas diluições seriadas que foram semeadas em placas contendo meios de cultura específicos e então foi determinado o número de Unidade Formadoras de Colônias por mililitro (UFC/mL). Após análise estatística os resultados mostraram que o grupo 1 (potência de 6,5W) e o grupo 2 (potência de 7,5W) não apresentaram diferença significativa. Não houve diferença do grupo em que houve a ativação do microrganismo, em relação ao grupo controle. Já o grupo 3 (potência de 13,6W) apresentou diferença significante, havendo diferença significativa do grupo em que houve a ativação do microrganismo. Com base nos resultados obtidos, conclui-se que uma potência mais elevada é mais eficaz na ação antimicrobiana de C. albicans. (AU)


The search for the optimization of clinical results led to the development of new technologies. The Dental Piezoelectric System (SPO) has been increasingly widespread and its main feature is the phenomenon of cavitation, which is the process of vaporization, generation of bubbles and their subsequent implosion. Such acoustic phenomena are directly related to the lysis of OM cell membranes. The aim of this study was to investigate the phenomenon of cavitation of the piezoelectric system, at different activation potencies, in relation to the antimicrobial effect on Candida albicans. To carry out the work, the DENTSURG device was used. A standard strain of Candida albicans (18060) was used, kept in a freezer at -80ºC in the Laboratory of Microbiology and Immunology of ICT UNESP. For Candida albicans activation, the strain was grown on Sabouraud agar with chloramphenicol and incubated in an oven for 24 h at 37°C. After OM preparation, 100µL of standardized cells were added in 24-well plates and after this step, a single trained operator performed the activation, with the different activation protocols. Subsequently, serial dilutions were performed and seeded in plates containing specific culture media and then the number of Colony Forming Units per milliliter (CFU/mL) was determined. After statistical analysis, the results showed that group 1 (6.5W power) and group 2 (7.5W power) showed no significant difference. There was no difference between the group in which the microorganism was activated and the control group. Group 3 (13.6W power) showed a significant difference, with a significant difference between the group in which the microorganism was activated. Based on the results obtained, it is concluded that a higher power is more effective in the antimicrobial action of C. albicans (AU)


Subject(s)
Ultrasonics , Candida albicans , Cavitation , Disinfection
20.
Heliyon ; 7(10): e08245, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34761135

ABSTRACT

Rhizophora mangle, one of the main neotropic mangrove species, has wide phenological variability associated with soil salinity. Since global warming is one of the main drivers of changes in salinity, understanding the influence of this variable at the species level would help improve the prediction of climate change in the ecological services provided by mangroves. To understand the physiological and/or anatomical responses to water stress generated by edaphic salinity and its relationship with phenological and structural diversity, we quantified the functional traits of leaf tissue subjected to a cross-seeding experiment between two forests with different ranges of natural salinity (0-18 PSU and 20 to 70 PSU). A total of 180 propagules, 90 native and 90 from the other forest, were planted in each forest. Every three months for a year, soil salinity and growth, adaptability, and survival of propagules that were transformed into seedlings were measured. The traits evaluated between the two saline regimes presented significant differences, as stated in the working hypothesis. Likewise, there were modifications in the hypodermis and the xylem vessels in the exchanged seedlings, tissues related to water storage, and conduction. These responses allowed native euhaline forest seedlings to grow in oligohaline. The opposite occurred with seedlings originating in low salinities that did not survive in high salinities. Differences in adaptability between populations of R. mangle subjected to ranges of contrasting salinity may imply changes at the structural level, zoning, and abundance of the species front to the climate change processes.

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