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2021 ◽  
Vol 9 (9) ◽  
pp. 1018
Author(s):  
Ting Wang ◽  
Xi Chen ◽  
Song Qin ◽  
Jialin Li

Synechococcus is a dominant genus of the coastal phytoplankton with an effective contribution to primary productivity. Here, the phylogenetic and phenogenetic composition of Synechococcus in the coastal Yellow Sea was addressed by sequencing marker gene methods. Meanwhile, its co-occurrence pattern with bacterial and eukaryotic microbes was further investigated based on the construction of networks. The result revealed that Synechococcus abundance ranged from 9.8 × 102 cells mL−1 to 1.6 × 105 cells mL−1, which was significantly correlated to sampling depth and nutrient contents of nitrite, ammonia, and dissolved silicon. A total of eight Synechococcus phylogenetic lineages were detected, of which clade III was dominant in most of the samples. Meanwhile, clade I increased along the water column and even reached a maximum value of 76.13% at 20 m of station B. Phenogenetically, Synechococcus PT3 was always the predominant pigment type across the whole study zone. Only salinity was significantly correlated to the phenogenetic constitution. The networks revealed that Synechococcus co-occurred with 159 prokaryotes, as well as 102 eukaryotes including such possible grazers as Gymnodinium clades and Alveolata. Potential function prediction further showed that microbes co-occurring with Synechococcus were associated with diverse element cycles, but the exact mechanism needed further experimentation to verify. This research promotes exploring regularity in the genomic composition and niche position of Synechococcus in the coastal ecosystem and is significant to further discuss its potential participation in materials circulation and bottom-up effects in microbial food webs.


2021 ◽  
Vol 11 (11) ◽  
pp. 5187
Author(s):  
Fernando Pagels ◽  
Ricardo N. Pereira ◽  
António A. Vicente ◽  
A. Catarina Guedes

Pigments from microalgae and cyanobacteria have attracted great interest for industrial applications due to their bioactive potential and their natural product attributes. These pigments are usually sold as extracts, to overcome purification costs. The extraction of these compounds is based on cell disruption methodologies and chemical solubility of compounds. Different cell disruption methodologies have been used for pigment extraction, such as sonication, homogenization, high-pressure, CO2 supercritical fluid extraction, enzymatic extraction, and some other promising extraction methodologies such as ohmic heating and electric pulse technologies. The biggest constrain on pigment bioprocessing comes from the installation and operation costs; thus, fundamental and applied research are still needed to overcome such constrains and give the microalgae and cyanobacteria industry an opportunity in the world market. In this review, the main extraction methodologies will be discussed, taking into account the advantages and disadvantages for each kind of pigment, type of organism, cost, and final market.


2020 ◽  
Vol 2 (1) ◽  
pp. 19
Author(s):  
Erick Fabian Mosquera Quiñonez ◽  
Juan Enrique Tacoronte Morales ◽  
Mirna Geraldine Cevallos Mina

Ecuador is one of the countries in the Latin American region with a high textile production. However, chemical treatment strategies in the Ambato, Tungurahua and Quito areas are inefficient and not systematically applied, and the volumes of dyes and pigment-type contaminants generate serious environmental problems. The treatments of indigo textile wastewater and related indigo derivatives are very complex. Taking these into consideration, a simple photochemical protocol in heterogeneous conditions was developed, for degrading “blue-indigo” (Ambato textile group) in solution, using TiO2 (Degussa P25, with a purity of ≈99% and BET surface area 50 ± 15 m2/g) and solar light at lab scale. The photocatalytic oxidation of “blue-indigo” in aqueous solution was assessed by solar irradiation, in the presence of TiO2 particles. The effect of indigo concentrations, pH and TiO2 loading for maximum degree of degradation were evaluated. The mineralization of “blue-indigo” was reported by measuring COD-i and COD-f of the solution that was irradiated with sunlight under optimized conditions. The results enable the re-designing of strategies for controlling contamination in textile wastewaters in eco-sustainable conditions for Ecuador.


2020 ◽  
Vol 49 (D1) ◽  
pp. D667-D676 ◽  
Author(s):  
Laurence Garczarek ◽  
Ulysse Guyet ◽  
Hugo Doré ◽  
Gregory K Farrant ◽  
Mark Hoebeke ◽  
...  

Abstract Cyanorak v2.1 (http://www.sb-roscoff.fr/cyanorak) is an information system dedicated to visualizing, comparing and curating the genomes of Prochlorococcus, Synechococcus and Cyanobium, the most abundant photosynthetic microorganisms on Earth. The database encompasses sequences from 97 genomes, covering most of the wide genetic diversity known so far within these groups, and which were split into 25,834 clusters of likely orthologous groups (CLOGs). The user interface gives access to genomic characteristics, accession numbers as well as an interactive map showing strain isolation sites. The main entry to the database is through search for a term (gene name, product, etc.), resulting in a list of CLOGs and individual genes. Each CLOG benefits from a rich functional annotation including EggNOG, EC/K numbers, GO terms, TIGR Roles, custom-designed Cyanorak Roles as well as several protein motif predictions. Cyanorak also displays a phyletic profile, indicating the genotype and pigment type for each CLOG, and a genome viewer (Jbrowse) to visualize additional data on each genome such as predicted operons, genomic islands or transcriptomic data, when available. This information system also includes a BLAST search tool, comparative genomic context as well as various data export options. Altogether, Cyanorak v2.1 constitutes an invaluable, scalable tool for comparative genomics of ecologically relevant marine microorganisms.


2020 ◽  
Vol 35 (3) ◽  
pp. 408-418
Author(s):  
Petronela Nechita

AbstractThe work presented in this paper is focussed on study of structure and properties of coating layers based on natural pigments (ground calcium carbonate and clay) and butadiene acrylonitrile latex as binder in correlation with functional properties of the final coated paper. It is quantified the influence of binder content and pigment type on the structural and liquids penetration properties of coating layer. The obtained results confirm that by increasing of binder content in the coating formulations a reduced efficiency of light-scattering and increased roughness for coated surfaces is obtained. At the high binder amounts (over 15 pph), the coating layer porosity is reduced and as result a lower liquids penetration in the coated papers is obtained.


2020 ◽  
Vol 21 (17) ◽  
pp. 6129 ◽  
Author(s):  
Tokimasa Hida ◽  
Takafumi Kamiya ◽  
Akinori Kawakami ◽  
Jiro Ogino ◽  
Hitoshi Sohma ◽  
...  

Melanogenesis is the biological and biochemical process of melanin and melanosome biosynthesis. Melanin is formed by enzymic reactions of tyrosinase family proteins that convert tyrosine to form brown-black eumelanin and yellow-red pheomelanin within melanosomal compartments in melanocytes, following the cascades of events interacting with a series of autocrine and paracrine signals. Fully melanized melanosomes are delivered to keratinocytes of the skin and hair. The symbiotic relation of a melanocyte and an associated pool of keratinocytes is called epidermal melanin unit (EMU). Microphthalmia-associated transcription factor (MITF) plays a vital role in melanocyte development and differentiation. MITF regulates expression of numerous pigmentation genes for promoting melanocyte differentiation, as well as fundamental genes for maintaining cell homeostasis. Diseases involving alterations of EMU show various forms of pigmentation phenotypes. This review introduces four major topics of melanogenesis cascade that include (1) melanocyte development and differentiation, (2) melanogenesis and intracellular trafficking for melanosome biosynthesis, (3) melanin pigmentation and pigment-type switching, and (4) development of a novel therapeutic approach for malignant melanoma by elucidation of melanogenesis cascade.


2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Shuqiang Lyu ◽  
Yiyi Liu ◽  
Miaole Hou ◽  
Qinli Yin ◽  
Wangting Wu ◽  
...  

Abstract Background Mixed pigment analysis is an important and complex subject in preserving and restoring Chinese paintings since the colors observed by our naked eyes or instruments such as hyperspectral cameras are usually a mixture of several kinds of pigments. The purpose of this study was to explore a more effective method to confirm the type of every pure pigment and their proportion in pigment mixtures on the surface of paintings. Methods Two endmember extraction algorithms were adopted to identify the types of pigments and an improved method of ratio spectra derivative spectrophotometry was used to determine their proportion. Main works (1) Extracting the pure pigment components from mixed spectrum by adopting two blind source separation algorithms: Independent Component Analysis and Non-negative Matrix Factorization; (2) matching the separated pure spectrum with the pigment spectral library built in our laboratory to determine the pigment type; and (3) calculating the proportions of mixed pigments using the Ratio Spectra Derivative Spectrophotometry based on Mode, which is improved based on the original algorithm. Finally, a comparison was made with two abundance inversion algorithms: Least Squares Algorithm and Minimum Volume Simplex Analysis. The correlation coefficient and root mean square error were used to provide evidence for accuracy evaluation. Conclusions (1) Non-negative matrix factorization is more suitable for endmember extraction; and (2) Ratio spectra derivative spectrophotometry based on mode is more suitable for abundance inversion.


2019 ◽  
Vol 9 (4) ◽  
pp. 72-74
Author(s):  
Suraj Raj Bhattarai ◽  
Abhisekh Bhattarai ◽  
Kishor Kumar Tamrakar

A bile duct stone is defined as large if it is more than 15mm in size and giant when it is 5cm or more. Giant staghorn calculi are usually uncommon but can be found in oriental cholangio-hepatitis and usually pigment stones. Bile infection appears to be the initial event leading to stone formation. The primary bile duct stones form within the bile ducts and usually of brown pigment type while secondary bile duct stones arise from gall bladder and intra or extra hepatic ducts. There are very few published reports which describe a giant staghorn calculus in the common bile duct (CBD). The purpose of this case report is to report a new rare case of giant staghorn CBD calculus and discuss the diagnostic and surgical approach because staghorn calculi are very rare in the biliary tract.


2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Marcelo Coelho Goiato ◽  
Adhara Smith Nobrega ◽  
Emily Vivianne Freitas da Silva ◽  
Daniela Micheline dos Santos ◽  
André Pinheiro de Magalhães Bertoz ◽  
...  

Objective. The aim of this study was to evaluate the tear strength of MDX4-4210 and A-2186 silicones with different intrinsic pigments incorporated by mechanical and industrial methods, comparing nonaged and aged groups. Materials and Methods. Twenty-four groups were created according to the American Society for Testing and Materials D-624/type C, half nonaged and half aged (n = 10): bronze mechanical MDX4-4210, bronze industrial MDX4-4210, black mechanical MDX4-4210, black industrial MDX4-4210, pink mechanical MDX4-4210, pink industrial MDX4-4210, bronze mechanical A-2186, bronze industrial A-2186, black mechanical A-2186, black industrial A-2186, pink mechanical A-2186, and pink industrial A-2186. All specimens were submitted to tear strength analysis. Data were submitted to the ANOVA and Tukey test (p<0.05). Results. An increase in the tear strength values was observed only for the bronze and black MDX4-4210, comparing nonaged and aged silicones (p<0.05), regardless of the manufacturing method. There was a difference in all comparisons between MDX4-4210 and A-2186 silicones with the same pigment type (p<0.05), regardless of the manufacturing method. In all cases, there was no difference in the manufacturing method comparing the MDX4-4210 or A-2186 groups with the same pigment. Conclusion. Accelerated aging did not influence the tear strength in all aged A-2186 silicones and in aged pink industrial and mechanical MDX4-4210 silicones. The other MDX4-4210 groups had an increase in the results after aging. In all cases compared, the A-2186 groups had higher tear strength values than the MDX4-4210 groups. Mechanical and industrial methods can be used for silicone preparation, without changing the tear strength.


2019 ◽  
Vol 27 (5(137)) ◽  
pp. 160-169 ◽  
Author(s):  
Janina Leks-Stępień

The pigment coating of paper is usually performed to enhance the physical properties of paper and its printability. The coating generally makes paper whiter, brighter and more opaque. The properties of the coated paper depend, among others, on the porous structure of the coating developed, which is determined by the pigments, binders and their reactions. The influence of the type and quantity of coating components and ink absorption into the coating layer was studied in this work. Printing ink penetration was measured using a Penetration Dynamic Analyser with an HVL module (High Viscous Liquid). The evenness of liquid penetration into paper was measured using a Penetration Dynamic Analyser with a PEA module (Print Evenness Analyser). Results obtained indicate that all three variables – coating pigment type, latex dose and ink type – may have an equally strong influence on liquid and ink penetration,and thus on print quality.


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