PHYTOCHEMICAL SCREENING, CONTRIBUTION TO THE STUDY OF THE ANTIFUNGAL EFFECT OF FLAVONOIDS FROM DIFFERENT PARTS OF ZIZIPHUS LOTUS OF SOUTH-WEST ALGERIA

The biodiversity of our country allows us to medicinal plants used in the new research directions most of the plants used in traditional medicine for centuries. Because of the resistance of the proliferation of parasitic fungi in the food industries, plant diseases, this work aims to test the antifungal activity of a plant heritage which is the Ziziphus lotus. The phytochemical screening allowed us to see that the flavonoids extracts of leaves, roots, and seeds covered in this study are rich in bioactive substances namely alkaloids, flavonoids, saponins, tannins, and terpenes. Antifungal activity was tested using two methods; radial growth on solid media and evaluation of biomass on liquid environments against Aspergillus flavus-parasiticus and Aspergillus ochraceus. The results of the evaluation of the radial growth show that the extract of flavonoids of the best roots given percent inhibition of 73.3% against A. ochraceus has 4.37×10−4  g/ml concentration, followed by extraction of flavonoids grains that gave an inhibition of 55% against the Aspergillus flavus-parasiticus has 1.091×10−3 g/ml concentration. However, another extract of Z. lotus gave a fairly significant inhibition of fungal strains studied very limited. The results of the evaluation of biomass on liquid medium show the efficacy vis-à-vis studied extracts of the strains tested in accordance with the increase of the concentration thereof. The best inhibition was recorded for extraction of flavonoids grain against the two strains tested 61.92% for Aspergillus flavus-parasiticus and 84.33% for A. ochraceus 1.091×10−3 g/ml concentration.Keywords: Ziziphus lotus, Extracts flavonoids, Antifungal activity, Aspergillus flavus-parasiticus, Aspergillus ochraceus

Fully Transparent Gas Sensor Based on Carbon Nanotubes

In this paper, we demonstrate the feasibility of realization of transparent gas sensors based on carbon nanotubes (CNTs). Both sensing layer and electrodes consist of CNTs deposited by spray deposition. The transparent sensor—with a transmittance higher than 60% in both sensing layer and electrodes—is characterized towards NH3 and CO2 and compared with a reference sensor with the same active layer but evaporated Au electrodes. In particular, the sensitivity towards NH3 is virtually identical for both reference and transparent sensors, whereas the transparent device exhibits higher sensitivity to CO2 than the reference electrode. The effect of the spacing among consecutive electrodes is also studied, demonstrating that a wider spacing in fully CNT based sensors results in a higher sensitivity because of the higher sensing resistance, whereas this effect was not observed in gold electrodes, as their resistance can be neglected with respect to the resistance of the CNT sensing layer. Overall, the transparent sensors show performance comparable—if not superior—to the traditionally realized ones, opening the way for seamlessly integrated sensors, which do not compromise on quality.This work has been partially supported by the fellowship H2020-MSCA-IF-2017-794885-SELFSENS and the TUM Graduate Schoo

Gain-tunable complementary common-source amplifier based on a flexible hybrid thin-film transistor technology

In this letter, we report a flexible complementary common-source (CS) amplifier comprising one p-type spray-coated single walled carbon nanotube and one n-type sputtered InGaZnO4 thin-film transistor (TFT). Bottom-gate TFTs were realized on a free-standing flexible polyimide foil using a maximum process temperature of 150 °C. The resulting CS amplifier operates at 10 V supply voltage and exhibits a gain bandwidth product of 60 kHz. Thanks to the use of a p-type TFT acting as a tunable current source load, the amplifier gain can be programmed from 3.5 V/V up to 27.2 V/V (28.7 dB). To the best of our knowledge, this is the highest gain ever obtained for a flexible single-stage CS amplifiers

Clinical and laboratory characteristics of short-term mortality in Egyptian patients with acute heart failure

Objective: To identify the clinical and laboratory predictors of short-term mortality in patients with acute heart failure (AHF). Subjects and methods: We conducted a prospective, single center study on 120 consecutive patients presented with acute heart failure to the emergency department. All patients had clinical, laboratory, electrocardiographic and echocardiographic evaluation. Short-term mortality was reported within 30 days of presentation. Results: Mean age was 59.29 ± 10.1 years, 55.8% were males and 50.8% were smokers. The common AHF presentations were dyspnea (91.7%), chest tightness (62.5%) and lower limb edema (54.2%). Ischemic heart disease, diabetes and hypertension were present in 72.5%, 43.3% and 35% of patients, respectively. Short-term mortality was reported in 29 patients (24.16%); most of them died in-hospital (19 patients, 65.52%). The following parameters were significantly associated with short-term mortality: hypoxia (P < 0.001), tachycardia (P < 0.01), raised jugular venous pressure (JVP) (P < 0.001), low systolic blood pressure (P < 0.01), prolonged PR interval (P < 0.007), atrial fibrillation (AF) (P < 0.038), left bundle branch block (LBBB) (P < 0.04), impaired kidney function (P < 0.007), anemia (P < 0.029), hyponatremia (P < 0.006), hypoalbuminemia (P < 0.005), dilated left ventricle (LV) (P < 0.001), low LV ejection fraction (LVEF) (P < 0.001), and dilated left atrium (LA) (P < 0.002). ROC curve analysis showed that low LVEF (≤24%), dilated LV end diastolic diameter (LVESD) ≥ 66.5 mm, dilated LV end systolic diameter (LVESD) ≥ 53.5 mm, dilated LA diameter ≥ 48 mm, increased serum creatinine ≥ 1.6 mg/dl, and decreased serum albumin ≤ 3 g/dl can significantly predict short-term mortality in patients with acute heart failure. Conclusion: Variable clinical, laboratory, electrocardiographic and echocardiographic parameters were associated with short-term mortality. Our study showed that low LVEF, dilated LV diameter, dilated LA diameter, impaired kidney function and low serum albumin can predict short-term mortality in patients with acute heart failure

Transfer Printed P3HT/PCBM Photoactive Layers: From Material Intermixing to Device Characteristics

The fabrication of organic electronic devices involving complex stacks of solution-processable functional materials has proven challenging. Significant material intermixing often occurs as a result of cross-solubility and postdeposition treatments, rendering the realization of even the simplest bilayer architectures rather cumbersome. In this study we investigate the feasibility of a dry transfer printing process for producing abrupt bilayer organic photodiodes (OPDs) and the effect of thermal annealing on the integrity of the bilayer. The process involves the transfer of readily deposited thin films of poly­(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM) using a polydimethylsiloxane (PDMS) stamp. Fabricated structures are characterized by means of cross-sectional scanning electron microscopy (SEM), UV/vis absorption spectroscopy, and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Joint consideration of all results unveils abrupt interfaces with no thermal treatment applied and significant material intermixing for samples annealed above 100 °C. The role of the thermally assisted intermixing in determining the performance of complete devices is evaluated through the comparison of <i>J</i>–<i>V</i> characteristics and external quantum efficiencies (EQEs) of identical photodiodes subject to different annealing conditions. It is shown that the performance of such devices approaches the one of bulk heterojunction photodiodes upon thermal annealing at 140 °C for 5 min. Our results demonstrate that transfer printing is a reliable and simple process for the realization of functional multilayers, paving the way for organic electronic devices incorporating complex stacks. It further contributes to a fundamental understanding of material composition within photoactive layers by elucidating the process of thermally assisted intermixing

Fully-Sprayed and Flexible Organic Photodiodes with Transparent Carbon Nanotube Electrodes

In this study, we demonstrate the feasibility of TCO-free, fully sprayed organic photodiodes on flexible polyethylene terephthalate (PET) substrates. Transparent conducting films of single-wall carbon nanotubes are spray deposited from aqueous solutions. Low roughness is achieved, and films with sheet resistance values of 160 Ω/sq at 84% in transmittance are fabricated. Process issues related to the wetting of CNTs are then examined and solved, enabling successive spray depositions of a poly­(3,4-ethylenedioxythiophene):poly­(styrenesulfonate) (PEDOT:PSS) layer and a blend of regioregular poly­(3-hexylthiophene-2,5-diyl) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM). The active layer is then optimized, achieving a process yield above 90% and dark currents as low as 10^–4 mA/cm². An external quantum efficiency of 65% and high reproducibility in the performance of the devices are obtained. Finally, the impact of the characteristics of the transparent electrode (transmittance and sheet resistance) on the performances of the device are investigated and validated through a theoretical model and experimental data

Patterning poly(3-Hexylthiophene) in the sub-50-nm region by nanoimprint lithography

We use thermal and room temperature nanoimprint lithography (NIL) for directly patterning the photoactive polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) in the sub-50-nm region. Different types of molds were used to directly imprint the desired structures into P3HT thin films. Good pattern transfer is achieved independent of the presence of other underlying polymer layers or the type of substrate incorporated. Further, we discuss the future application of this technology to the fabrication of ordered heterojuction organic photovoltaic devices and demonstrate that the NIL process involved does not damage the polymer or alter its chemical or electrical properties