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1.
Recirculating Aquaculture Systems (RAS) reduce water consumption by efficient filtration to maintain appropriate levels of accumulating compounds and sludge. Sludge is mechanically separated by drum filters and disposed of to the detriment of overall system water budgets. Dissolved nitrogen compounds are reduced via nitrification–denitrification filters, requiring commercial external carbon sources. The reuse of sludge after ozone pre-treatment may represent the next step in RAS optimization. The present study analyzes the content of sludge from RAS and tests ozonation as a pre-treatment for recycling as carbon source. The dissociative effect of ozone and the physicochemical changes due to ozonation lead to a significant increase in soluble carbon availability. Predominantly long-chain fatty acid (FA) (saturated and unsaturated) with 16 and 18 carbon atoms independently of the treatment were found in the profiles. Saturated FA concentrations in solution increased after 20, 40, and 60 min ozonation. The solid content of the sludge was practically unaffected by ozonation in terms of FA profile: only saturated FA slightly increases after 40 min treatment. The implications of these findings for denitrifying bacteria are discussed.

Abbreviations: Recirculating Aquaculture Systems (RAS); Advanced Oxidation Processes (AOPs)  相似文献   

2.
Human red blood cells (RBCs) are unique cells with the remarkable ability to deform, which is crucial for their oxygen transport function, and which can be significantly altered under pathophysiological conditions. Here we performed ultrastructural analysis of RBCs as a peripheral cell model, looking for specific signatures of the neurodegenerative pathologies (NDDs)—Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD), utilizing atomic force (AFM) and conventional optical (OM) microscopy. We found significant differences in the morphology and stiffness of RBCs isolated from patients with the selected NDDs and those from healthy individuals. Neurodegenerative pathologies’ RBCs are characterized by a reduced abundance of biconcave discoid shape, lower surface roughness and a higher Young’s modulus, compared to healthy cells. Although reduced, the biconcave is still the predominant shape in ALS and AD cells, while the morphology of PD is dominated by crenate cells. The features of RBCs underwent a marked aging-induced transformation, which followed different aging pathways for NDDs and normal healthy states. It was found that the diameter, height and volume of the different cell shape types have different values for NDDs and healthy cells. Common and specific morphological signatures of the NDDs were identified.  相似文献   
3.
To incorporate microorganisms and to preserve their integrity, new matrices of poly(N‐acryloylglycine) have been designed under appropriate conditions. To understand the interactions between the microorganisms and the organic part of the matrices, different conetworks of poly(N‐acryloylglycine) have been synthesized and characterized. Copolymerization with two crosslinkers was performed with different compositions. The thermal and swelling properties of conetworks are specifically controlled and compared. These investigations show that the swelling ratio of these materials is compatible with the incorporation of biomolecules in these matrices. They successfully permit Pseudomonasspecies 1625 bacteria incorporation. The biological activity of bacteria is also preserved, allowing the use of these materials for innovative biological applications. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 835‐841, 2013  相似文献   
4.
Circular RNAs (circRNAs) are a group of special endogenous long non-coding RNAs which are highly stable in the circulation, and, thus, more suitable as new biomarkers of colorectal cancer (CRC). The aim of our study was to explore the plasma expression levels of four circRNAs: has_circ_0001445, hsa_circ_0003028, hsa_circ_0007915 and hsa_circ_0008717 in patients with CRC and to evaluate their associations with clinicopathological characteristics and the clinical outcome of the patients. CircRNAs were extracted from patients’ plasma obtained prior to chemotherapy. Their expression levels were measured by qPCR and calculated applying the 2−ΔΔCt method. The levels of all four circRNAs were significantly increased in the plasma of CRC patients. At the optimal cut-off values hsa_circ_0001445 and hsa_circ_0007915 in plasma could significantly distinguish between patients with or without metastatic CRC with 92.56% sensitivity and 42.86% specificity, and with 86.07% sensitivity and 57.14% specificity, respectively. The mean overall survival (OS) of patients with high/intermediate expression of hsa_circ_0001445 was 30 months, significantly higher in comparison with the mean OS of the patients with low expression—20 months (log-rank test, p = 0.034). In multivariate Cox regression analysis, the low levels of hsa_circ_0001445 were also associated with shorter survival (HR = 1.59, 95% CI: 1.02–2.47, p = 0.040). A prognostic significance of hsa_circ_0001445 for patients with metastatic CRC was established.  相似文献   
5.
The synthesis, EPR characterisation and biological evaluation of two new metallodendrimers, i.e. a poly(propyleneamine) dendrimer functionalized at the external surface with 4-bromo-1,8-naphthalimide and conjugated with Cu(II) and Zn(II), was performed with the aim to evaluate their antimicrobial and anticancer activity. The antimicrobial activity was investigated in meat-peptone broth against bacteria B. subtilis and P. aeruginosa, and the yeast C. lipolytica. The results showed that the compounds inhibited effectively the tested pathogens even after their deposition on a textile fabric. Anticancer activity was investigated against three human permanent cell lines from non-small cell lung cancer (A549), triple negative breast cancer (MDA-MB-231) and carcinoma of the uterine cervix (HeLa) in the c?=?0.01–30 μM concentration range. The results suggest that these compounds are promising for application in biomedicine as anticancer drugs in the design of new effective preparations. The antimicrobial and anticancer activity may be related to the peculiar structural and dynamical properties revealed for the Cu(II) complexes, by a computer aided analysis of the electron paramagnetic resonance (EPR) spectra. This analysis indicated the formation, at the lowest Cu(II) concentrations, of a flexible rhombic Cu-N4 coordination with the internal amino groups of the dendrimer, which transformed into a Cu2-N4 coordination already at 0.25 equiv. of Cu(II).  相似文献   
6.
The paper presents an experimental study of ultrasonic surface waves propagation in the low carbon steel specimens with different degree of degradation of microstructure and mechanical properties, subjected to tensile deformation. The purpose of this paper is to investigate and analyze the dependence between microstructure, mechanical and acoustic properties and to find appropriate parameters for stress state evaluation. For identification of degradation and stress state we use ultrasonic Rayleigh waves (URW) velocity variation obtained by in-line and off-line measurements. The degradation is imitated by structural changes caused by heat treatment.  相似文献   
7.
The pH indicator proposed is a water‐soluble dye based on benzo[de]antracen‐7‐one. Dissolving in buffered aqueous solution, it changes color from yellow to orange and in the mean time decreases its fluorescence emission as a function of the amine concentration. Viscose fabric, dyed with the same dye has been investigated as a new reversible colorimetric and fluorescent sensor material for ammonia and aliphatic amines in buffered solution. The high value of the dye pKa and the influence of the textile matrix on the selective detection of dimethylamine compared to ammonia, trimethylamine, and metylamine have been studied. The different response of the solution and textile matrix as well as the optical analyses both as a color change and a fluorescence emission have been discussed. The advantage of this sensor is the fact that depending on the analytical problem to be solved and the available instrumentation it can be used either as a fluorogenic or as a chromogenic chemosensor. In addition, the textile sensor is characterized by facile fabrication, low cost, sensibility, and reproducibility. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   
8.

Purpose

The purpose of the current study was to observe and correlate the characteristics of mucin balls to the ocular surface properties, and furthermore, to report the effect of different mucin balls size and number on structural alteration of the anterior cornea.

Methods

The study included, two groups of patients fitted with one-month continuous, extended wear lenses for therapeutic (group 1) and optical (group 2) purposes; the later serving as a control group. Group 1 was comprised of patients with recurrent erosion syndrome, while group 2 included subjects with mild myopia and voluntary use of continuous wear lenses. The examination was performed when mucin balls were encountered during a routine visit. Clinical examination was reinforced with laser scanning in vivo confocal microscopy, which provided microstructural observations. The appearance and size of the mucin balls were described and measured at two independent time points. Qualitative analysis included shape (round, elliptical and irregular) and reflectivity (bright, homogenous and dark, heterogonous).

Results

Clinically 1460 mucin balls were encountered (822 in group 1 and 638 in group 2). The number of mucin balls analyzed by in vivo confocal microscopy was 820. Diversity was higher in group 1. The mucin balls of group 2, were more uniform – rounded in shape 81,2% and regular in reflectivity 98%. Qualitative analysis revealed a negative correlation between the size of the balls and impact on the basal epithelium morphology and also “activation” of the anterior stroma in adjacent areas.

Conclusions

Mucin balls affect corneal surface including both epithelia disintegration as well as keratocyte “activation”. The main predisposing factor for mucin ball formation appear to be the corneal surface irregularity. As structural alterations of the cornea are transient, mucin balls might be beneficial for corneal restoration due to mechanical and/or biochemical stimulation. In vivo, confocal microscopy is an innovative tool for evaluating mucin balls in their diversity and dynamics.  相似文献   
9.
In this work, we describe for the first time the synthesis of a hydrogel with iron oxide nanoparticles, uniformly distributed in its structure on a polyamide fabric by surface initiated photopolymerization. The type of outgoing iron ions Fe(II), Fe(III), and the combination between them influences the properties of the iron oxide particles and the obtained composite materials (PAF2, PAF3, and PAF32). All composite materials have been investigated as catalysts in heterogeneous Fenton process for treating real industrial wastewater after dyeing of cotton fabric with reactive dye Drimarene K-7B. Different conditions on the degradation of this dye have been investigated. The best result for discoloration has been obtained with PAF2 at concentration 9.4 g L−1 and pH = 2.2 in the presence of H2O2 (93.3 mmol L−1, where 78% of dye was degraded for 24 h and 90.5%-for 48 h. The high salinity of wastewaters, typical for dyeing with reactive dyes favors discoloration, while surface-active agents hinder the process. The obtained material is reusable and is more effective in less polluted water solutions. It has been found that the composite material can be used repeatedly.  相似文献   
10.
<正>"与蒙德里安共进早餐"是一个实验性项目,空间的形式、使用的线条和颜色都旨在能够对使用者产生愉悦身心的积极影响。整个项目的设计灵感来源于荷兰画家蒙德里安的作品,他采用水平和垂直两种线条,以此构成各种不同的正方形和长方形,简单而又复杂的图形以红、黄、蓝三原色或黑、白、灰来表示色彩的纯净。在他的笔下色彩充满了活力,运用黄金分割和等比数列将画面或图形按照一定的比例进行分割、排列,创造富有节奏与韵律的秩序与  相似文献   
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