Structural properties of fluids interacting via piece-wise constant potentials with a hard core

The structural properties of fluids whose molecules interact via potentials with a hard core plus two piece-wise constant sections of different widths and heights are presented. These follow from the more general development previously introduced for potentials with a hard core plus $n$ piece-wise constant sections [Condens. Matter Phys. {\bf 15}, 23602 (2012)] in which use was made of a semi-analytic rational-function approximation method. The results of illustrative cases comprising eight different combinations of wells and shoulders are compared both with simulation data and with those that follow from the numerical solution of the Percus-Yevick and hypernetted-chain integral equations. It is found that the rational-function approximation generally predicts a more accurate radial distribution function than the Percus-Yevick theory and is comparable or even superior to the hypernetted-chain theory. This superiority over both integral equation theories is lost, however, at high densities, especially as the widths of the wells and/or the barriers increase.Comment: 10 pages, 11 figures; v2: Old Fig. 1 removed, new text on the correlation length, 7 new references added, plus other minor change

Gallic acid and cyclodextrins : inclusion complexes and antimicrobial activity

Gallic acid (GA), or 3,4,5-trihydroxybenzoic acid, is the commonest and simplest phenolic acid, with just one aromatic ring. This phenolic molecule has been described as antioxidant, anti-inflammatory and anti-tumour, also, antimicrobial and anti-fungal activity has been attributed to it. Besides all the GA biological activities, this compound is cheap, due to the easy plant extraction, and non-toxic. Thus, this phenolic acid has been widely used in food, drugs and cosmetic industry. GA, as other phenolic compounds, is susceptible to environmental factors which may lead to the losing their structural integrity and bioactivity. This can be overcome by the encapsulation with cyclodextrins (CD). They are cyclic oligosaccharides arising from the degradation of starch; inexpensive and friendly to humans. CD are able to form an inclusion complex with a wide range of bioactive molecules, including hydrophobic ones, protect and modulate their release. In the present work, the formation of an inclusion complex (IC) between βCD, HPβCD (2-Hydroxypropyl-β-cyclodextrin) or MβCD (methyl-β-cyclodextrin) and GA was analysed by UV spectrophotometry. The antimicrobial activity of the complexes was also assessed, by qualitative and quantitative methods. The influence of the buffer and pH on the formation of the IC and on the GA antimicrobial activity was also tested. The IC formation was analysed in 2 buffer solutions (K2HPO4/ KH2PO4 and H3PO4/NaOH). The GA and IC absorbance spectrum showed different appearances depending on the buffer used. When K2HPO4/ KH2PO4 was used, the IC spectrum presented some alterations on the λmax comparatively to the GA spectrum. Since, the GA and ICs spectra obtained for the H3PO4/NaOH were similar, this buffer was selected. The IC formation between GA and βCD, HPβCD or MβCD was analysed at pH 5, 7 and 8. Based on the results it was clear that the pH used affected the IC formation in the conditions tested. The βCD formed IC 1:1 with GA for all pH values, being the pH5 the most favourable. The same was observed for MβCD, but these CD had the lowest values for the association constant, meaning that the IC formation between MβCD and GA is not very efficient. Regarding the HPβCD, in neutral pH the IC formed was 1:2 and for the others pH was 1:1, pH5 was the most favourable for the IC formation and pH7 the least. The antimicrobial activity was assessed for the best combinations of GA/CD (βCD pH5 and pH7; HPβCD pH5 and pH8). For all the IC tested, the antimicrobial activity of GA was improved or alike to the GA without encapsulation. To the authors knowledge, the IC formation between HPβCD or MβCD and GA has not been reported until know, as well as the antimicrobial activity of the IC βCD/GA and HPβCD/GA

Gut microbiota impact on Angolan children with sickle cell disease

FCT/Aga Khan (project nº330842553).FCT_UIDB/05608/2020. FCT_UIDP/05608/2020.Introduction: Clinical manifestations of Sickle cell disease (SCD) are very heterogeneous, and the intestinal microbiome appears to be crucial in the modulation of inflammation, cell adhesion, and induction of aged neutrophils, which are the main interveners of recurrent vaso-occlusive crisis. Enterocyte injury, increased permeability, altered microbial composition, and bacterial overgrowth have all been documented as microbial and pathophysiologic changes in the gut microbiome of SCD patients in recent research studies. Microbiota analysis in SCD populations will be essential to demonstrate the importance of specific bacteria and their function in this disease and provide new insights for attenuating symptoms and new drug targets. Purpose: Given this, our aim is to sequence by NGS bacterial 16S RNA gene in order to characterize the gut microbiome of SCD children and healthy siblings, as a control.info:eu-repo/semantics/publishedVersio

Assessment of antimicrobial activity of textiles for wound dressing: methodology optimization

Normally, the skin is capable of restore the tissue integrity, after wound injury. However, the deposition of bacteria on the wound site results on infection causing pain and healing delay. To control bacteria proliferation, antimicrobial textiles have been developed, and the assessment of their activity is a required step. Although, several standard methods were published to assess textiles antimicrobial activity, they are time and material consuming and have some shortcomings with regard to the real conditions of use. Therefore, the aim of this work was to optimize the method described on JIS L 1902:2008-Testing for antibacterial activity and efficacy on textile products, the most commonly used standard. Two textile samples were used: A-cotton without treatment (control) and B-cotton with 10% of the recommend concentration of Ruco-bac AGP. The microorganism used was Staphylococcus aureus-ATCC 6538. The first improvement was sample size. On the qualitative method, square samples with 1x1cm2 were used instead 2.5x2.5cm2 (suggested by the standard). For sample A no antimicrobial activity was observed and for sample B the halo size was similar for both sizes used. For the quantitative method, the samples used had 0.4g (standard suggestion) and 0.1g. Sample A had the same bacterial growth before and after contact with the fabric and sample B had no bacterial growth. With this improvement, the amount of sample and solutions need for the test was reduced four times. To reduce the use of disposable material, instead of 50mL falcons, 6 well plates were used. In this case, no bacteria were recovered from the sample A after incubation period on 6 well plates. These means, that the centrifugation is a crucial step to detach all bacteria from the fabric. The effect of the bacterial inoculum volume was also assessed. Three inoculum volumes (250, 100 and 50µL) were added to 0,1g samples. No significant differences were observed for both samples. A healthy skin has 105bacteria/cm2 and up to this value it is considered that the skin is infected. Therefore, 3 inoculum concentrations were tested-3x105, 3x106, 3x107cell/mL. The results showed that the inoculum concentration had no significant changes for both samples after the incubation period. In conclusion, it is possible to use samples 4 times smaller than the standard suggestion, use higher inoculum volume to simulate wound exudate and higher concentration, to accurately predict the sample behaviour on an infected skin

Microsatellite Markers For Urochloa Humidicola (poaceae) And Their Transferability To Other Urochloa Species

Background: Urochloa humidicola is a warm-season grass commonly used as forage in the tropics and is recognized for its tolerance to seasonal flooding. This grass is an important forage species for the Cerrado and Amazon regions of Brazil. U. humidicola is a polyploid species with variable ploidy (6X-9X) and facultative apomixis with high phenotypic plasticity. However, this apomixis and ploidy, as well as the limited knowledge of the genetic basis of the germplasm collection, have constrained genetic breeding activities, yet microsatellite markers may enable a better understanding of the species' genetic composition. This study aimed to develop and characterize new polymorphic microsatellite molecular markers in U. humidicola and to evaluate their transferability to other Urochloa species. Findings: A set of microsatellite markers for U. humidicola was identified from two new enriched genomic DNA libraries: the first library was constructed from a single sexual genotype and the second from a pool of eight apomictic genotypes selected on the basis of previous results. Of the 114 loci developed, 72 primer pairs presented a good amplification product, and 64 were polymorphic among the 34 genotypes tested. The number of bands per simple sequence repeat (SSR) locus ranged from 1 to 29, with a mean of 9.6 bands per locus. The mean polymorphism information content (PIC) of all loci was 0.77, and the mean discrimination power (DP) was 0.87. STRUCTURE analysis revealed differences among U. humidicola accessions, hybrids, and other Urochloa accessions. The transferability of these microsatellites was evaluated in four species of the genus, U. brizantha, U. decumbens, U. ruziziensis, and U. dictyoneura, and the percentage of transferability ranged from 58.33% to 69.44% depending on the species. Conclusions: This work reports new polymorphic microsatellite markers for U. humidicola that can be used for breeding programs of this and other Urochloa species, including genetic linkage mapping, quantitative trait loci identification, and marker-assisted selection.

A simple ceramic process aimed at sustainability

Foi desenvolvido um processo cerâmico de elevada simplicidade, que foi aplicado com sucesso à produção de produtos utilitários e decorativos em barro vermelho, com impacto favorável em termos ambientais, económicos e sociais, e por isso com efeito positivo sobre a sustentabilidade. O projeto desenvolvido neste processo, consiste essencialmente numa simbiose entre a valorização da manufatura e a redução do impacto ambiental do processo cerâmico, o que foi conseguido através da utilização de um barro vermelho local (Mendalvo, Alcobaça, Portugal) que se mostrou apto à conformação de produtos cerâmicos e compativel com vários vidrados, embora se tenha optado pela utilização de um vidrado transparente pela ausência de metais de transição corantes na sua composição.A highly simple ceramic process was developed and successfully applied to the production of utilitarian and decorative products in red clay, with a favorable impact in environmental, economic and social terms and therefore with a positive effect on sustainability. The project developed in this process, essentially consists of a symbiosis between the valorization of the manufacture and the reduction of the environmental impact of the ceramic process, which was achieved through the use of a local red clay (Mendalvo, Alcobaça, Portugal) that proved to be capable of forming ceramic products and compatible with several glazed, although it was decided to use a transparent glaze due to the absence of dye transition metals in its composition

Machine Learning Algorithms for Peripheral Blood Cell Classification - A Hemovision Project Experience

This research explores the use of machine learning algorithms to classify nucleated peripheral blood cells. The ResNet18 convolutional neural network was used to pre-process the images and replace the dense layers; and for the output, the Support Vector Machine (SVM) classifier was chosen. Images from different datasets were used for training and testing the model. Thus, the developed model achieved an accuracy and F1-Score of 99.96%. In face of the obtained results, it was found that machine learning algorithms can be satisfactorily integrated into educational and diagnostic support processes

Effects of Sensory Behavioral Tasks on Pain Threshold and Cortical Excitability

Background/objective: Transcutaneous electrical stimulation has been proven to modulate nervous system activity, leading to changes in pain perception, via the peripheral sensory system, in a bottom up approach. We tested whether different sensory behavioral tasks induce significant effects in pain processing and whether these changes correlate with cortical plasticity. Methodology/principal findings: This randomized parallel designed experiment included forty healthy right-handed males. Three different somatosensory tasks, including learning tasks with and without visual feedback and simple somatosensory input, were tested on pressure pain threshold and motor cortex excitability using transcranial magnetic stimulation (TMS). Sensory tasks induced hand-specific pain modulation effects. They increased pain thresholds of the left hand (which was the target to the sensory tasks) and decreased them in the right hand. TMS showed that somatosensory input decreased cortical excitability, as indexed by reduced MEP amplitudes and increased SICI. Although somatosensory tasks similarly altered pain thresholds and cortical excitability, there was no significant correlation between these variables and only the visual feedback task showed significant somatosensory learning. Conclusions/significance: Lack of correlation between cortical excitability and pain thresholds and lack of differential effects across tasks, but significant changes in pain thresholds suggest that analgesic effects of somatosensory tasks are not primarily associated with motor cortical neural mechanisms, thus, suggesting that subcortical neural circuits and/or spinal cord are involved with the observed effects. Identifying the neural mechanisms of somatosensory stimulation on pain may open novel possibilities for combining different targeted therapies for pain control

Development of biofunctional textiles by the application of resveratrol to cotton, bamboo and silk

The goal of this work was to create a new generation of greener fabrics made of natural materials. For that, resveratrol (Res), obtained from Polygonum cuspidatum extract and known to have antibacterial, antifungal, and anti-inflammatory activity, was applied by an exhaustion method to cotton, bamboo, and silk knit fabrics. The fabrics adsorption behavior was tested and the amount of Res adsorbed was determined by its decrease on the immersion solutions with time and measured by spectrophotometry at 350 nm. The maximum adsorption capacity was observed for silk and it was independent of pH conditions used (50.5 % at pH=7 and 58.3 % at pH=5 of the initial Res concentration). At acidic pH conditions, cotton adsorbed 51.2 % of Res and Bamboo adsorbed only 28.1 % in 15 min. However, neither cotton nor bamboo adsorbed Res at pH=7. The release behavior was also analyzed and the highest Res release was observed for cotton in alkaline sweat and urine mimic solutions. The lowest release was achieved by cotton in water (1.0 ng/ml). Moreover, no relation was found between the amounts of Res adsorbed or released and cell viability. In conclusion, this work shows that it is possible to obtain cotton, bamboo, and silk functionalized with resveratrol. The incorporating process here described is simple and silk-Res can be presented as a good combination

Microsatellite markers for urochloa Humidicola (poaceae) and their transferability to other urochloa species

Urochloa humidicola is a warm-season grass commonly used as forage in the tropics and is recognized for its tolerance to seasonal flooding. This grass is an important forage species for the Cerrado and Amazon regions of Brazil. U. humidicola is a polyploid species with variable ploidy (6X-9X) and facultative apomixis with high phenotypic plasticity. However, this apomixis and ploidy, as well as the limited knowledge of the genetic basis of the germplasm collection, have constrained genetic breeding activities, yet microsatellite markers may enable a better understanding of the species' genetic composition. This study aimed to develop and characterize new polymorphic microsatellite molecular markers in U. humidicola and to evaluate their transferability to other Urochloa species. Findings: A set of microsatellite markers for U. humidicola was identified from two new enriched genomic DNA libraries: the first library was constructed from a single sexual genotype and the second from a pool of eight apomictic genotypes selected on the basis of previous results. Of the 114 loci developed, 72 primer pairs presented a good amplification product, and 64 were polymorphic among the 34 genotypes tested. The number of bands per simple sequence repeat (SSR) locus ranged from 1 to 29, with a mean of 9.6 bands per locus. The mean polymorphism information content (PIC) of all loci was 0.77, and the mean discrimination power (DP) was 0.87. STRUCTURE analysis revealed differences among U. humidicola accessions, hybrids, and other Urochloa accessions. The transferability of these microsatellites was evaluated in four species of the genus, U. brizantha, U. decumbens, U. ruziziensis, and U. dictyoneura, and the percentage of transferability ranged from 58.33% to 69.44% depending on the species. Conclusions: This work reports new polymorphic microsatellite markers for U. humidicola that can be used for breeding programs of this and other Urochloa species, including genetic linkage mapping, quantitative trait loci identification, and marker-assisted selection8