147 research outputs found

    Cyanobacterial community patterns as water quality bioindicators

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    The main goal of this study was to examine the use of cyanobacteria for evaluating the quality of running water. Accordingly epilithic cyanobacterial communities were collected in Dez River and Ojeyreb drain in south of Iran. Samples were collected in two seasons: autumn and spring. Effective physical and chemical factors on the structure of cyanobacterial communities and the dispersion of the species in relation with them were determined using PCA and CCA analyses. The Shannon-Wiener biodiversity index was used to define the species diversity. The concentration of nitrate as main nutrient had significant increase in Drain stations. A decline in species richness was observed associated with these increases in nutrient load in both seasons in different cyanobacterial community structure. The results indicated that order Oscillatoriales had higher proportion of cyanobacteria species at Drain. The species Oscillatoria chlorina, Chroococcus minor, Phormidium tenue and Lyngbya kuetzingii S had the most positive correlation with nutrient factor. Species Lyngbya infixa and Lyngbya mesotrichia had the most negative correlation with nitrate. Our results confirm the using of cyanobacteria species as indicators for monitoring eutrophication in rivers and define them as water eutrophication bioindicators

    A novel intervention technology for cerebral palsy: Brain stimulation

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    A common pediatric disorder with posture and motor dysfunction in neurological diseases is known as cerebral palsy (CP). Recently, a series of effective techniques have been developed for treatment of CP. These promising methods need high-tech equipment for brain stimulation and mainly classified into invasive and no-invasive approaches. This study aimed to introduce these techniques for treatment of patients who suffer from CP. The potential and performance of currently available brain stimulation techniques have been mentioned in detail. Moreover, the clinical application, safety, efficacy and challenges of these methods have been discussed. Here we review the recent advances in the CP treatment with an emphasis on brain stimulation techniques. © 2019, Iranian Child Neurology Society. All rights reserved

    Damage imaging post processing for delamination size assessment of CFRP aeronautic structures

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    Thanks to their high strength to mass ratio, composite materials are now widespread in the aerospace industry. Nevertheless, this type of material is sub- ject to internal damages like delamination. In order to detect and localize these damages, robust and precise Structural Health Monitoring algorithms exist for this purpose and have been validated experimentally. However, in order to avoid struc- tures catastrophic failures and to estimate their residual life, there is still a huge need of reliable damage size assessment methods. In this paper, a damage quanti cation method is proposed. This strategy is based on the extraction of a damage size sen- sitive feature computed from damage imaging results. Here damage imaging stands for methods that use ultrasonic Lamb waves-based map of damage localization like- lihood index. This feature is extracted from each labelled example of a training set in order to infer a mathematical model used to predict the area of a delamination of unknown damages. The proposed method is successfully validated on experimental data carried out on CFRP plate samples equipped with a piezoelectric transducers network.This work has received funding from the European Union's Horizon 2020 research and innovation program under the REMAP project (grant agreement number 769288). https://h2020-remap.eu

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Assessment of impact detection tchniques for aeronautical application: ANN vs. LSSVM

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    The Impact localisation in composite panels is assessed using two machine learning techniques: least square support vector machines (LSSVM) and artificial neural networks (ANN) with local strain signals from piezoelectric sensors. Sensor signals from impact experiments on a composite plate as well as signals simulated by a finite element model are used to train and test models. A comparative study shows that LSSVM achieves better accuracy than ANN on identifying location of impacts for a combination of large mass impact and small mass impact, in particular when less data is available for training which is more appropriate for real aeronautical application. Additionally, LSSVM is more capable of identifying new impact events which have not been considered in the training process

    Damage detectability model of pitch-catch configuration in composite plates

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    Detectability of damage using Lamb waves depends on many factors such as size and severity of damage, attenuation of the wave and distance to the transducers. This paper presents a detectability model for pitch-catch sensors configuration for structural health monitoring (SHM) applications. The proposed model considers the physical properties of lamb wave propagation and is independent of damage detection algorithm, which provides a generic solution for probability of detection. The applicability of the model in different environmental and operational conditions is also discussed

    Fluoride doping into SiO2-MgO-CaO bioactive glass nanoparticles: bioactivity, biodegradation and biocompatibility assessments

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    In this research, for the first time, the structure, bioactivity, biodegradation and biocompatibility of SiO2-MgO-CaO glasses doped with different levels of fluoride were studied. The glassy powder samples were synthesized by a coprecipitation method followed by calcination at 500 °C, where amorphicity and fluoride incorporation were verified by X-ray diffraction and Raman spectroscopy, respectively. The in vitro biomineralization and biodegradation of the samples were also investigated by electron microscopy, Raman spectroscopy and inductively coupled plasma optical emission spectrometry. These assessments revealed that there is an optimum level of fluoride doping to meet the highest bioactivity. Remarkably, the same level of incorporation presented the foremost biocompatibility with respect to osteoblast-like MG-63 human cells, as realized by the MTT assay and cell attachment studies

    Gating behavior of endoplasmic reticulum potassium channels of rat hepatocytes in diabetes

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    BACKGROUND: Defects in endoplasmic reticulum homeostasis are common occurrences in different diseases, such as diabetes, in which the function of endoplasmic reticulum is disrupted. It is now well established that ion channels of endoplasmic reticulum membrane have a critical role in endoplasmic reticulum luminal homeostasis. Our previous studies showed the presence of an ATP-sensitive cationic channel in endoplasmic reticulum. Therefore, in this study, we examined and compared the activities of this channel in control and diabetic rats using single-channel recording techniques. METHOD: Male Wistar rats were made diabetic for 2 weeks with a single dose injection of streptozotocin (45 mg/kg). Ion channel incorporation of rough endoplasmic reticulum of diabetic hepatocytes into the bilayer lipid membrane allowed the characterization of K+ channel. RESULTS: Ion channel incorporation of rough endoplasmic reticulum vesicles into the bilayer lipid revealed that the channel current-voltage (I-V) relation with a mean slope conductance of 520 +/- 19 pS was unaffected in diabetes. Interestingly, the channel Po-voltage relation was significantly lower in diabetic rats at voltages above +30 mV. CONCLUSION: We concluded that the endoplasmic reticulum cationic channel is involved in diabetes. Also, this finding could be considered as a goal for further therapeutic plans
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