Physical and chemical impacts of conventional unit processes and coagulants on the dinoflagellate, Ceratium hirundinella

2016 ◽  
Vol 11 (4) ◽  
pp. 754-764
Author(s):  
H. Ewerts ◽  
S. Janse van Vuuren ◽  
A. Swanepoel ◽  
L. Tiedt
Keyword(s):  
Cell Damage ◽  
Hydrated Lime ◽  
Organic Polymer ◽  
Cell Integrity ◽  
Water Treatment Process ◽  
Ceratium Hirundinella ◽  
Drinking Water Production ◽  
Plate Cell ◽  
Physical And Chemical ◽  
Conventional Unit

The freshwater dinoflagellate, Ceratium hirundinella (C. hirundinella) with its complex morphology and robust thecal plate cell covering, is responsible for extensive problems during drinking water production. To have a better understanding of these problems, knowledge of what happens to the integrity of the cells after each step of the conventional water treatment process is essential. Therefore, the aim of this study was to investigate the physical and chemical impacts of conventional unit processes (prior to sand filtration) on the morphology of C. hirundinella cells and the appearance of cells in aggregation or in flocs. Source water samples enriched with C. hirundinella cells (>500 cells/ml) were used to conduct jar stirring experiments. Samples for scanning electron microscopy (SEM) were collected from raw water, after flash mixing and from the sediment that formed when dosing various coagulant chemicals. The coagulant options included hydrated lime and activated silica (Ca(OH)2-SiO2) which increase the pH to levels above 10, hydrated lime in combination with organic polymer (Ca(OH)2-poly) that increases the pH to levels of approximately 9 and organic polymer (poly) alone which has no effect on the pH of the water. Results obtained from SEM investigations revealed significant damage to the cells due to flash mixing, as well as due to the dosing of Ca(OH)2-SiO2. When dosing organic polymer alone, no further impacts on the cell integrity were observed after flash mixing, but it resulted in poor cell removal. Ca(OH)2-poly caused less damaging effects to the cells when compared to Ca(OH)2-SiO2, but resulted in moderate removal of C. hirundinella cells. Treatment plants that experience algal-related problems, especially during coagulation should consider using SEM to select appropriate coagulant dosages in order to avoid further cell damage that may occur during floc formation.

Histological evaluation of cochlear hair cell damage from noise-induced hearing loss in chinchillas

1990 ◽  
Vol 48 (3) ◽  
pp. 332-333
Author(s):  
R.V. Harrison ◽  
R.J. Mount ◽  
P. White ◽  
N. Fukushima
Keyword(s):  
Hair Cell ◽  
Evoked Potential ◽  
Cell Damage ◽  
Acoustic Trauma ◽  
Histological Evaluation ◽  
Cell Integrity ◽  
Functional Changes ◽  
Cochlear Hair Cell ◽  
Left And Right ◽  
Contralateral Ear

In studies which attempt to define the influence of various factors on recovery of hair cell integrity after acoustic trauma, an experimental and a control ear which initially have equal degrees of damage are required. With in a group of animals receiving an identical level of acoustic trauma there is more symmetry between the ears of each individual, in respect to function, than between animals. Figure 1 illustrates this, left and right cochlear evoked potential (CAP) audiograms are shown for two chinchillas receiving identical trauma. For this reason the contralateral ear is used as control.To compliment such functional evaluations we have devised a scoring system, based on the condition of hair cell stereocilia as revealed by scanning electron microscopy, which permits total stereociliar damage to be expressed numerically. This quantification permits correlation of the degree of structural pathology with functional changes. In this paper wereport experiments to verify the symmetry of stereociliar integrity between two ears, both for normal (non-exposed) animals and chinchillas in which each ear has received identical noise trauma.

scholarly journals Application of Physical and Chemical Enhanced Backwashing to Reduce Membrane Fouling in the Water Treatment Process Using Ceramic Membranes

Membranes ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 110 ◽  
Author(s):  
Seogyeong Park ◽  
Joon-Seok Kang ◽  
Jeong Lee ◽  
Thi-Kim-Quyen Vo ◽  
Han-Seung Kim
Keyword(s):  
Membrane Fouling ◽  
Ceramic Membranes ◽  
Operating Efficiency ◽  
Operating Pressure ◽  
Chemical Safety ◽  
Water Treatment Process ◽  
Effluent Flow Rate ◽  
Influent Water ◽  
Physical And Chemical ◽  
Carbon Concentrations

This study investigated the improvement of operating efficiency through physical cleaning and chemical enhanced backwashing (CEB) using ceramic membranes with high permeability and chemical safety compared to organic membranes. The turbidity and DOC (Dissolved Organic Carbon) concentrations were selected to ensure that the degree of contamination was always constant. The operating pressures were fixed at 100, 200, and 300 kPa, and the filtration was terminated when the effluent flow rate decreased to 30% or less from the initial value. After filtration, backwashing was performed at a pressure of 500 kPa using 500 mL backwash water. The membrane was cleaned by dipping in NaOCl, and a new washing technique was proposed for steam washing. In this study, we investigated the recovery rate of membranes by selectively performing physical cleaning and CEB by changing the influent water quality and operating pressure conditions.

Zinc Selenide Quantum Dots Light Emitting Devices (ZnSe QDs-LEDs) with Different Organic Polymers

2017 ◽  
Vol 18 ◽  
pp. 11-19 ◽  
Author(s):  
Akeel M. Kadim
Keyword(s):  
Quantum Dots ◽  
Zinc Selenide ◽  
White Light ◽  
Color Temperature ◽  
Organic Polymer ◽  
Broad Emission Band ◽  
Light Emitting Devices ◽  
Hybrid Devices ◽  
White Luminescence ◽  
Physical And Chemical

The physical and chemical characterize of quantum dots (QDs) extensively depend upon the optical and morphological factors such as size and shape. The zinc selenide (ZnSe) quantum dots (QDs) have been prepared by chemical method and used to fabricate quantum dot hybrid junction devices with different types of organics polymers. The optical studies illustrate that the band gap value from the photoluminescence (PL) with high intensity of these QDs is found about 3.1 eV. The electroluminescence's (EL) hybrid devices were demonstrated by room temperature PL and electroluminescence (EL). Current-voltage (I–V) characteristics indicate that the output current is good compared to the few voltages (5.5 V) used which gives good results to get a generation of white light. The EL spectrum reveals a broad emission band covering the range from 350 - 700 nm. The emissions producing this white luminescence were recognized depending on the chromaticity coordinates (CIE 1931). The correlated color temperature (CCT) was found to be about 5759, 3500 and 3498 K for ITO/TPD/ZnSe, ITO/PPV/ZnSe and ITO/PEDOT/ZnSe QDs respectively. Fabrication of EL- hybrid devices from semiconductors materials (ZnSe QDs) with holes injection organic polymer (TPD, PPV and PEDOT) was effective in white light generation.

scholarly journals Eco-friendly production of metal nanoparticles immobilised on organic monolith for pepsin extraction

2020 ◽  
Vol 22 (1) ◽  
pp. 18-28
Author(s):  
Eman Alzahrani ◽  
Ashwaq T. Alkhudaidy
Keyword(s):  
Visual Observation ◽  
Sem Analysis ◽  
Porous Polymer ◽  
Organic Polymer ◽  
High Porosity ◽  
Polymer Monoliths ◽  
Spectra Analysis ◽  
Edx Analysis ◽  
Physical And Chemical ◽  
Monolithic Components

AbstractPolymer monoliths modified by using nanoparticles (NPs) integrate high NP specific surface area with different monolith surface chemistry and high porosity. As a result, they have extensive applications within different fields, whereas nanomaterial-functionalised porous polymer monoliths have elicited considerable interest from investigators. This study is aimed at fabricating organic polymer-based monoliths from polybutyl methacrylate-co-ethylenedimethacrylate (BuMA-co-EDMA) monoliths prior to immobilization of gold or silver metal on the pore surface of the monoliths using reducing reagent (extracts of lemon peels). This was intended to denote a sustainable technique of immobilizing nanoparticles that are advantageous over physical and chemical techniques because it is safe in terms of handling, readily available, environmentally friendly, and cheap. Two different methods were used in the study to effectively immobilize nanoparticles on monolithic components. The outcomes showed that soaking the monolith rod in the prepared nano solution directly and placing it within ovens at temperatures of 80°C constituted the most effective method. Characterisation of the fabricated monolith was undertaken using SEM/EDX analysis, UV-vis. spectra analysis, and visual observation. The SEM analysis showed that nanoparticles were extensively immobilised on the surface polymers. Another peak was attained through EDX analysis, thus confirming the Au atom existence at 2.83% alongside another peak that proved the Ag atom existence at 1.92%. The fabricated components were used as sorbents for purifying protein. The ideal performance was achieved using gold nanoparticles (GNPs) immobilised organic monolith that attained a greater pepsin extraction recovery compared to silver nanoparticles (SNPs) immobilised organic monoliths alongside bare organic-based monolith.

Microbial Production of Schwertmannite: Development from Microbial Fundamentals to Marketable Products

2017 ◽  
Vol 262 ◽  
pp. 568-572 ◽  
Author(s):  
Susan Reichel ◽  
Eberhard Janneck ◽  
Diana Burghardt ◽  
Stefan Peiffer ◽  
Gunter Kießig ◽  
...  
Keyword(s):  
Mine Water ◽  
Ferrous Iron ◽  
Iron Hydroxide ◽  
Iron Oxidation ◽  
Research Work ◽  
Industrial Effluents ◽  
Open Pit ◽  
Organic Polymer ◽  
Water Treatment Process ◽  
Ferrous Iron Oxidation

Pumped groundwater in the lignite open-cast mines in Lusatia, Germany, contains a high level of ferrous iron (up to 1000 mg/L) at an initial pH of about 5. In recent R&D projects G.E.O.S. developed an innovative water treatment process for ferrous iron oxidation using the autochthonous microbial consortium in the mine water. The pilot plant is operated in the Nochten open-pit mine in cooperation with the LEAG and produces 5 – 10 t of schwertmannite per year. Extensive research work was carried out in parallel to utilize the produced schwertmannite. Pigment production proved to be technically feasible but difficult due to economic and market constraints. However, the high affinity of schwertmannite to oxy-anions provides the suitability for utilization as adsorbent to remove arsenate, antimonate, chromate, molybdate, vanadate or phosphate from mine water or industrial effluents. In the R&D project SURFTRAPII two kinds of filter-stable sorption materials were developed 1) by compacting schwertmannite or 2) by adhesive curing using an organic polymer, respectively. The produced filter-stable adsorbents were tested under technical conditions in cooperation with potential end users to remove arsenate, molybdate and phosphate from mine and industrial water and to concentrate valuable metals. The results showed a better performance of the material compared to other commercially available iron hydroxide adsorbents.

scholarly journals UV Curable Heat Resistant Epoxy Acrylate Coatings

2010 ◽  
Vol 4 (3) ◽  
pp. 205-216
Author(s):  
Firdous Habib ◽  
◽  
Madhu Bajpai ◽  
Keyword(s):  
Heat Resistance ◽  
Chemical Resistance ◽  
Polymeric Materials ◽  
Organic Polymer ◽  
Epoxy Acrylate ◽  
Uv Curable ◽  
Heat Resistant ◽  
Acrylate Resin ◽  
Physical And Chemical ◽  
Silicone Acrylate

Polymeric materials are exposed to high temperatures that results in lowering of the film integrity. A blend of an epoxy resin with the silicone acrylate resin was developed to provide high heat resistance UV cured coatings. Earlier siliconized epoxy coatings had been developed by conventional curing. But due to environmental awareness, high productivity rate, low process costs and energy saving UV curable coatings are enjoying considerable growth. Thermally stable UV cured coatings used in the present study were developed from silicone acrylate and epoxy acrylate resin with different diluents and photoinitiator. Such coatings provide higher thermal stability (693 K) along with physical and chemical resistance. In addition, such coatings can also be obtained by using functional amino silanes. The resin developed provides a simple and practical solution to improve heat resistance along with physical and chemical resistance of the UV cured coatings. The purpose of this research paper is to develop UV curable heat resistant coatings by the combination of inorganic and organic polymer, taking epoxy acrylate as a base resin.

IL-9 Modulated MUC4 Gene and Glycoprotein Expression in Airway Epithelial Cells

2006 ◽  
Vol 26 (1) ◽  
pp. 55-67 ◽  
Author(s):  
Gautam Damera ◽  
Baoyun Xia ◽  
Hanumatha R. Ancha ◽  
Goverdhan P. Sachdev
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Damage ◽  
Airway Epithelial Cells ◽  
Lung Cancer Cell Line ◽  
Airway Epithelial ◽  
Cell Integrity ◽  
Western Blots ◽  
Mrna Stabilization ◽  
Muc4 Expression

Compromised epithelial cell integrity is a common feature associated with chronic lung inflammatory states such as asthma. While epithelial cell damage is largely due to sustained effects of inflammatory mediators localized to airways, the subsequent process of epithelial cell differentiation is attributed to members of the transmembrane receptor tyrosine kinase family called the ErbB's. MUC4, a large molecular weight membrane-bound glycoprotein, has recently been identified as a potential ligand for the ErbB-2 receptor. In this study, we investigated the possible role of interleukin-9 (IL-9), a Th2 cytokine, on MUC4 expression using a lung cancer cell line, NCI-H650. We determined that IL-9 up-regulates MUC4 expression in a time and concentration-dependent fashion. Nuclear run-on assays indicated transcriptional regulation of MUC4 while no post-transcriptional mRNA stabilization was observed by actinomycin D chase experiments. IL-9 also increased MUC4 glycoprotein expression as determined by Western blots using a monoclonal antibody specific for a non-tandem repeat region on ASGP-2 region of MUC4. Furthermore, a JAK3-selective inhibitor 4-(4′-hydroxyphenyl) amino-6, 7-dimethoxyquinazoline (WHI-P131), substantially reduced IL-9-induced MUC4 mRNA expression in a dose-dependent fashion. These results implicate a potential role for IL-9 upon MUC4 expression in human airway epithelial cells.

Complex permittivity measurements of RF plasma polymerized polyterpenol organic thin films employing split post dielectric resonator

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Kateryna Bazaka ◽  
Mohan V. Jacob
Keyword(s):  
Thin Films ◽  
Low Cost ◽  
Polymer Thin Films ◽  
Wavelength Region ◽  
Thickness Measurement ◽  
Organic Polymer ◽  
Rf Plasma ◽  
Potential Applications ◽  
Permittivity Measurements ◽  
Physical And Chemical

Abstract In the fields of organic electronics and biotechnology, applications for organic polymer thin films fabricated using low-temperature non-equilibrium plasma techniques are gaining significant attention because of the physical and chemical stability of thin films and the low cost of production. Polymer thin films were fabricated from non-synthetic terpinen-4-ol using radiofrequency polymerization (13.56 MHz) on low loss dielectric substrates and their permittivity properties were ascertained to determine potential applications for these organic films. Real and imaginary parts of permittivity as a function of frequency were measured using the variable angle spectroscopic ellipsometer. The real part of permittivity (k) was found to be between 2.34 and 2.65 in the wavelength region of 400–1100 nm, indicating a potential low-k material. These permittivity values were confirmed at microwave frequencies. Dielectric properties of polyterpenol films were measured by means of split post dielectric resonators (SPDRs) operating at frequencies of 10 GHz and 20 GHz. Permittivity increased for samples deposited at higher RF energy – from 2.65 (25 W) to 2.83 (75 W) measured by a 20-GHz SPDR and from 2.32 (25 W) to 2.53 (100 W) obtained using a 10-GHz SPDR. The error in permittivity measurement was predominantly attributed to the uncertainty in film thickness measurement.

scholarly journals Vitrification of Ovarian Tissue from Non-Human Primates

2017 ◽  
Vol 45 (1) ◽  
pp. 13
Author(s):  
Adriel Behn Brito ◽  
Cinthia Távora de Albuquerque Lopes ◽  
Ana Paula Ribeiro Rodrigues ◽  
José Ricardo de Figueiredo ◽  
Sheyla Farhayldes Souza Domingues ◽  
...  
Keyword(s):  
Cell Damage ◽  
Ovarian Tissue ◽  
Genetic Material ◽  
Reproductive Function ◽  
Practical Method ◽  
Primate Species ◽  
Future Application ◽  
Success Rates ◽  
Female Reproduction ◽  
Physical And Chemical

Background: One of the strategies to preserve genetic material from nonhuman primates (NHP) consists in the implementation of germplasm banks, for future application in reproductive biotechniques, as well as for biomedical research. Based on the success rates achieved in human, there is a prominent possibility to succeed also with NHP. However, studies with NHP are still scarce, especially regarding the cryopreservation of ovarian tissue.Review: Neotropical non-human primates, especially males, have been used in research related to reproductive biotechniques in Brazil. Regarding research on female reproduction and ovarian tissue preservation, most studies were performed using domestic animals as models. Current concepts and controversies in the restoration of gametes in adult females does not exclude the needs to preserve ovarian tissue. Importantly, ovarian tissue can be collected and preserved even after the death of the donors, being applied when finding dead females. Furthermore, collection of ovarian biopsies is also feasible and will not affect reproductive function. Among the cryopreservation methods, the vitrification has been indicated due to practical logistic, as well as because it will avoid the formation of large intracellular ice crystals, and it is claimed that ovarian stromal damage will be decreased under vitrification. Considering the number of threatened primate species and the needs to preserve their habitat, but also their gametes, development of preservation protocols are needed. Among the procedures, vitrification appears as a practical method to be applied in the near future. Although a low number of studies is reported, most of them were performed in the recent years. In this context, this article reviews recent information on the vitrification of ovarian tissue of non-human primates. Due to the limited number of studies in these species, observed data are compared with the literature in domestic and human mammals.Conclusion: Despite the advances summarized here, it is possible to conclude that there is still a need to improve procedures for the preservation of genetic material, including in post-mortem situations. The technique of vitrification, therefore, consists of a feasible and promising option. However, it is needed to study properly the methods of vitrification, as well as the introduction of new systems and supplements to minimize or avoid the cell damage caused by the cryopreservation procedure (physical and chemical).

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