Modeling electroporation of the non-treated and vacuum impregnated heterogeneous tissue of spinach leaves

Uniform electroporation of the heterogeneous structure of spinach leaf cross section is a technological challenge that is addressed in this investigation. Three dimensional models were created with cells arranged in specific tissue types, considering a leaf with its air fraction and a leaf where the air fraction was replaced by a solution of known properties using vacuum impregnation. The models were validated before electroporation, in the frequency domain, where alternating voltage and current signal at frequencies from 20 Hz to I MHz were used to measure conductivity of the tissue. They were also validated through measurements of current during electroporation when a single 250 mu s rectangular pulse with amplitudes ranging from 50 to 500 V was applied. Model validations show that both the frequency dependent conductivity and electroporation are well predicted. The importance of the wax layer and stomata in the model is thoroughly discussed. Industrial relevance: Our aim was to investigate electroporation of the spinach leaf by developing a model which would enable us to meet the technological challenge of achieving uniform electroporation in a highly heterogeneous structure in the context of a process aimed at improving freezing stability of plant foods. Pulsed electric field treatment may be used to introduce the cryoprotectant molecules into the cells, and hence improve the structure and properties of frozen food plants. (C) 2014 Elsevier Ltd. All rights reserved

Local cryotherapy as an adjunct to the treatment of patients with degeneration of the hip

Wstęp. Mechanizm choroby zwyrodnieniowej stawów przypomina błędne koło, dochodzi do osłabienia siły mięśniowej lub zaburzenia równowagi mięśniowej. Materiał i metody. 72 pacjentów ze zmianami zwyrodnieniowymi stawu biodrowego podzielono na dwie grupy A i B w zależności od zastosowanej terapii. Wyniki. U badanych zastosowanie miejscowej krioterapii wpłynęło na zmniejszenie bólu oraz znaczną poprawę ruchu zgięcia i wyprostu stawu biodrowego. Wnioski. Krioterapia miejscowa jest skuteczną metodą wspomagającą leczenie pacjentów ze zmianami zwyrodnieniowymi stawu biodrowego.Introduction. The mechanism of osteoarthritis resembles a vicious circle, occur muscle weakness or muscle imbalance. Material and methods. 72 patients with osteoarthritis of the hip divided into two groups A and B, depending on the therapy. Results. In the patients local cryotherapy treatment had impact on pain reduction and a significant improvement in flexion and extension of the hip. Conclusions. Local cryotherapy is an effective adjunct to the treatment of patients with osteoarthritis of the hip

The Camberwell Assessment of Need for the Elderly questionnaire as a tool for the assessment of needs in elderly individuals living in long-term care institutions

AbstractObjectivesThe aim of the study was to evaluate the Camberwell Assessment of Need for the Elderly questionnaire (CANE) in assessing the needs of elderly individuals living in long-term care institutions (LTCI) in Poland.Setting and ParticipantsThe needs of 173 residents were assessed. The inclusion criteria were age (at least 75 years of age) and the lack of severe cognitive impairment (Mini Mental Scale Examination score of at least 15 points).MeasurementsIn all participants, met and unmet needs were assessed by themselves and by the nursing staff involved in care activities.ResultsThe number of met needs assessed by the staff was higher than in the users’ opinions (p<0.0001), whereas the number of unmet needs was lower (p<0.001). However, the average percentage of the agreement between the user and the staff was as high as 86.2%. The areas characterized by the lowest agreement were Company (65.3%), Memory (75.7%), Eyesight/hearing/communication (70.5%) and Psychological distress (70.5%).ConclusionsDespite a high percentage of agreement reached between the staff and user assessments of needs in our study, we were able to identify the areas of discrepancies between these two perceptions of needs. These can be treated as signals pointing to those aspects of care that should be addressed

Modeling electroporation of the non-treated and vacuum impregnated heterogeneous tissue of spinach leaves

Uniform electroporation of the heterogeneous structure of spinach leaf cross section is a technological challenge that is addressed in this investigation. Three dimensional models were created with cells arranged in specific tissue types, considering a leaf with its air fraction and a leaf where the air fraction was replaced by a solution of known properties using vacuum impregnation. The models were validated before electroporation, in the frequency domain, where alternating voltage and current signal at frequencies from 20 Hz to 1 MHz were used to measure conductivity of the tissue. They were also validated through measurements of current during electroporation when a single 250 μs rectangular pulse with amplitudes ranging from 50 to 500 V was applied. Model validations show that both the frequency dependent conductivity and electroporation are well predicted. The importance of the wax layer and stomata in the model is thoroughly discussed. Industrial relevance: Our aim was to investigate electroporation of the spinach leaf by developing a model which would enable us to meet the technological challenge of achieving uniform electroporation in a highly heterogeneous structure in the context of a process aimed at improving freezing stability of plant foods. Pulsed electric field treatment may be used to introduce the cryoprotectant molecules into the cells, and hence improve the structure and properties of frozen food plants

Zirconium-based metal–organic frameworks as acriflavine cargos in the battle against coronaviruses : a theoretical and experimental approach

[Image: see text] In this study, we present a complementary approach for obtaining an effective drug, based on acriflavine (ACF) and zirconium-based metal–organic frameworks (MOFs), against SARS-CoV-2. The experimental results showed that acriflavine inhibits the interaction between viral receptor-binding domain (RBD) of spike protein and angiotensin converting enzyme-2 (ACE2) host receptor driving viral cell entry. The prepared ACF@MOF composites exhibited low (MOF-808 and UiO-66) and high (UiO-67 and NU-1000) ACF loadings. The drug release profiles from prepared composites showed different release kinetics depending on the local pore environment. The long-term ACF release with the effective antiviral ACF concentration was observed for all studied ACF@MOF composites. The density functional theory (DFT) calculations allowed us to determine that π–π stacking together with electrostatic interaction plays an important role in acriflavine adsorption and release from ACF@MOF composites. The molecular docking results have shown that acriflavine interacts with several possible binding sites within the RBD and binding site at the RBD/ACE2 interface. The cytotoxicity and ecotoxicity results have confirmed that the prepared ACF@MOF composites may be considered potentially safe for living organisms. The complementary experimental and theoretical results presented in this study have confirmed that the ACF@MOF composites may be considered a potential candidate for the COVID-19 treatment, which makes them good candidates for clinical trials

Impregnation of Leaf Tissues and its Consequences on Metabolism and Freezing; Study on Vacuum Impregnation and Pulsed Electric Field Treatment

Freezing is a widely used method of preserving food products. Efforts are currently being directed towards improving the quality of the sensitive tissues of plant foods such as leaves, after freezing and thawing. One of the methods under investigation is the combination of vacuum impregnation (VI) with cryoprotectants and the application of a pulsed electric field (PEF) to the plant tissue prior to freezing. The main aims of this work were to identify mechanisms for the efficient introduction of a cryoprotectant molecule into the heterogeneous structure of leaf tissue, and to improve our understanding of the consequences of the introduction of this foreign molecule into the tissue regarding cell metabolism, freezing point and ice propagation rate. Leaf tissue is characterized by a high degree of heterogeneity, being composed of cells of different shapes and sizes arranged in easily distinguishable layers interspersed with a branched network of air spaces. It is of key importance to obtain uniform and optimal impregnation of the cryoprotectant molecule in this complex structure. PEF parameters leading to the uniform electroporation of the leaf surface and the bulk tissue were determined experimentally using fluorescence microscopy and electrical resistance measurements, respectively. The results suggest that the level of electroporation is highly influenced by pulse polarity, the number of pulses, and the interval between pulses. To obtain precise information on the electroporation of internally located cells, a three-dimensional numerical model of the cross section of a leaf was developed. Models were constructed using representations of both the untreated and the vacuum impregnated leaf. The models were validated in the frequency domain, where alternating voltage and current at frequencies from 20 Hz to 1 MHz were used to measure the conductivity of the tissue. The models were also validated through measurements of current during electroporation, where a single 250 μs rectangular pulse with amplitudes ranging from 50 to 500 V was applied. Validation of the models showed that both the frequency-dependent conductivity and electroporation are well predicted. The importance of the wax layer and stomata in the model and the pore density in the membranes of specific internal tissues are thoroughly discussed. The metabolic consequences of VI and PEF treatment were explored. The results showed that VI, and the subsequent application of PEF, increased the metabolic activity. It was also shown that VI drastically decreased the porosity of the leaves. However, a small air fraction remained in the tissue, suggesting that the oxygen-consuming pathways are active in the cells after VI. The increase in metabolic activity after VI was accompanied by the accumulation of trehalose-6-phosphate in the cells. The influence of VI with different sugars and PEF on ice propagation rates and freezing temperature was investigated. Leaves impregnated with trehalose, sucrose, glucose and mannitol exhibited significantly lower ice propagation rates and higher freezing temperatures than untreated controls. Leaves subjected to PEF also showed higher freezing temperatures than untreated leaves; however, the ice propagation rate was not influenced by PEF. The combination of VI and PEF resulted in freezing temperatures and ice propagation rates comparable to those for leaves subjected to VI only

A manifesto of a postmodern aesthetics in The savage detectives and 2666 of Roberto Bolaño.

Celem niniejszej pracy jest analiza dwóch powieści chilijskiego pisarza, Roberta Bolaño, pod kątem cech odpowiadających powieści postmodernistycznej. Praca składa się z dwóch części, teoretycznej i praktycznej. W pierwszym rozdziale została zamieszczona charakterystyka dzieł postmodernistycznych i zgodnie z tymi wytycznymi dokonano interpretacji Dzikich detektywów, oraz 2666. Analiza miała na celu wyróżnienie i omówienie takich pojęć jak: intertekstualność, polifoniczność, miejsce i czas w powieści postmodernistycznej, zatarcie granic pomiędzy gatunkami literackimi oraz nowy typ bohatera. Część praktyczna składa się z dwóch dużych rozdziałów, przy czym każdy rozdział odpowiada analizie jednej powieści. Interpretacja pozwoliła przedstawić manifest estetyki postmodernizmu na przykładzie dzieł chilijskiego pisarza.The object of this thesis is to present an analysis of the postmodern characteristics in two books of Chilean novelist, Roberto Bolaño. This work consists of two parts, one of them is theoretical and another one is analytical. The present thesis analyzes The savage detectives and 2666 in consideration to postmodern theories, which are presented in the first chapter. The purpose of this work is to investigate intertextuality, polyphony, time and space in postmodernism, combination of genres and a new type of a literary character. The part of the analysis consists of two big chapters which are interpretations of those books. The investigation permits the thesis and allows to read The savage detectives and 2666 as examples of the manifesto of the postmodern aesthetics.El objetivo de esta tesina es analizar la presencia de los rasgos característicos de la novela postmoderna en dos obras del escritor chileno, Roberto Bolaño. El trabajo consta de dos partes, de la parte teórica y la parte de análisis. La tesina realiza una investigación de Los detectives salvajes y 2666 a partir de la característica de las obras postmodernas, que se presenta en el primer capítulo. Se analiza los elementos postmodernos tales como la intertextualidad, la polifonía, el tiempo y el espacio postmodernos, la mezcla de los géneros literarios, la aparición de un nuevo héroe literario. La parte de análisis consta de dos grandes capítulos que son interpretaciones de las obras. El estudio permite confirmar la tesis y representar las obras del escritor chileno como los ejemplos del manifiesto de la estética postmoderna

Influence of Pulsed Electric Field Protocols on the Reversible Permeabilization of Rucola Leaves

Reversible electropermeabilization of plant tissues with heterogeneous structure represents a technological challenge as the response of the different structures within the same specimen to the application of electric field may differ due to different cell sizes, extracellular space configurations, and electrical properties. The influence of five different pulsed electric field protocols with different pulse polarity, number of pulses (25, 50, 75, 100, 250, and 500), and intervals between pulses (no intervals and 1- and 2-ms intervals) on the reversible permeabilization of rucola (Eruca sativa) leaves was investigated. The electric field intensity was 600 V/cm. Electrical resistance of the bulk tissue was measured before and after electroporation, and propidium iodide was used to analyze the electroporation at the surface of the leaf. Leaf viability was assessed from survival in storage, and cell viability was investigated with fluorescein diacetate. Results indicate that the viability of the leaves could not be predicted by measurements of electrical resistance or permeabilization levels of the leaf surface. Higher survival rate was demonstrated when applying bipolar pulses compared with monopolar pulses, but the latter proved to be more effective than bipolar pulses for permeabilizing the surface of the leaves. Longer intervals between bipolar pulses resulted in increased viability preservation, while the number of electroporated cells on the leaf surface was comparable for all tested protocols