scholarly journals Exopolysaccharides from Cyanobacteria: Strategies for Bioprocess Development

2020 ◽  
Vol 10 (11) ◽  
pp. 3763 ◽  
Author(s):  
Diogo Cruz ◽  
Vitor Vasconcelos ◽  
Guillaume Pierre ◽  
Philippe Michaud ◽  
Cédric Delattre
Keyword(s):  
Downstream Processing ◽  
Bioprocess Development ◽  
Relevant Research ◽  
Carbon Neutrality ◽  
Chemical Complexity ◽  
Production Parameters ◽  
Specific Trait ◽  
Bioactive Potential ◽  
Selection Of ◽  
Challenges And Strategies

Cyanobacteria have the potential to become an industrially sustainable source of functional biopolymers. Their exopolysaccharides (EPS) harbor chemical complexity, which predicts bioactive potential. Although some are reported to excrete conspicuous amounts of polysaccharides, others are still to be discovered. The production of this strain-specific trait can promote carbon neutrality while its intrinsic location can potentially reduce downstream processing costs. To develop an EPS cyanobacterial bioprocess (Cyano-EPS) three steps were explored: the selection of the cyanobacterial host; optimization of production parameters; downstream processing. Studying the production parameters allow us to understand and optimize their response in terms of growth and EPS production though many times it was found divergent. Although the extraction of EPS can be achieved with a certain degree of simplicity, the purification and isolation steps demand experience. In this review, we gathered relevant research on EPS with a focus on bioprocess development. Challenges and strategies to overcome possible drawbacks are highlighted.

scholarly journals Human body burdens of chemicals used in plastic manufacture

2009 ◽  
Vol 364 (1526) ◽  
pp. 2063-2078 ◽  
Author(s):  
Holger M. Koch ◽  
Antonia M. Calafat
Keyword(s):  
Analytical Chemistry ◽  
Bisphenol A ◽  
The United States ◽  
Environmental Chemicals ◽  
Biological Matrices ◽  
Relevant Research ◽  
Biomarkers Of Exposure ◽  
Accuracy And Precision ◽  
High Degree ◽  
Selection Of

In the last decades, the availability of sophisticated analytical chemistry techniques has facilitated measuring trace levels of multiple environmental chemicals in human biological matrices (i.e. biomonitoring) with a high degree of accuracy and precision. As biomonitoring data have become readily available, interest in their interpretation has increased. We present an overview on the use of biomonitoring in exposure and risk assessment using phthalates and bisphenol A as examples of chemicals used in the manufacture of plastic goods. We present and review the most relevant research on biomarkers of exposure for phthalates and bisphenol A, including novel and most comprehensive biomonitoring data from Germany and the United States. We discuss several factors relevant for interpreting and understanding biomonitoring data, including selection of both biomarkers of exposure and human matrices, and toxicokinetic information.

scholarly journals Thematic classification of English abbreviations for language teaching organizations. Introduction

2020 ◽  
Keyword(s):  
English Language ◽  
Language Teaching ◽  
Structural Type ◽  
Quantitative Composition ◽  
Relevant Research ◽  
Specific System ◽  
Parts Of Speech ◽  
The Common ◽  
Selection Of

The article analyzes the distribution of thematic subgroups (TSG) of English abbreviations within the thematic group (TG) "Names of language teaching organizations". Basing on the similar thematic classification studies of Ukrainian terminology, the authors found the lack of relevant research on English abbreviations, which, together with the need for their systematic thematic classification, allowed them to substantiate the relevance of the study, aimed to identify the said TSGs. The objectives involved the selection of the corpus, its analysis, as well as the formulation of conclusions and the prospects of further research. English terminology is a specific system based on the relevant conceptual features. It comprises a number of TGs, i.e. the sets of lexemes grouped together according to their extralinguistic properties. The criterion for defining a TG is a denotative feature reflecting the extralinguistic reality. The distribution of lexemes among the TGs is an important task of studying any terminological system. The corpus included 122 abbreviations selected from the original English-language sources. TSGs of English abbreviations within the said TG have varying degrees of complexity. The most sophisticated ones are the TSGs related to "Organizations directly involved in language teaching" (19%), "Government agencies" (14%) and some others. The proposed TSGs vary in their quantitative composition, structural type, parts of speech their full forms belong to, as well as the auxiliary words strategies. Some abbreviations are formally synonymic, though denoting different organizations. The analyzed TG includes ten TSGs, whose logic and clarity is provided for by the common conceptual features of their constituents, which are carriers of their thematic integrity. The said components are based on different term-formation models that constitute the prospect of further research.

scholarly journals Bayesian inference of the gene expression states of single cells from scRNA-seq data

2019 ◽  
Author(s):  
Jérémie Breda ◽  
Mihaela Zavolan ◽  
Erik van Nimwegen
Keyword(s):  
Gene Expression ◽  
Single Cell ◽  
Single Cells ◽  
Downstream Processing ◽  
Noise Removal ◽  
Rna Seq ◽  
Expression Of Genes ◽  
Normalization Methods ◽  
Quantify Gene Expression ◽  
Selection Of

AbstractIn spite of a large investment in the development of methodologies for analysis of single-cell RNA-seq data, there is still little agreement on how to best normalize such data, i.e. how to quantify gene expression states of single cells from such data. Starting from a few basic requirements such as that inferred expression states should correct for both intrinsic biological fluctuations and measurement noise, and that changes in expression state should be measured in terms of fold-changes rather than changes in absolute levels, we here derive a unique Bayesian procedure for normalizing single-cell RNA-seq data from first principles. Our implementation of this normalization procedure, called Sanity (SAmpling Noise corrected Inference of Transcription activitY), estimates log expression values and associated errors bars directly from raw UMI counts without any tunable parameters.Comparison of Sanity with other recent normalization methods on a selection of scRNA-seq datasets shows that Sanity outperforms other methods on basic downstream processing tasks such as clustering cells into subtypes and identification of differentially expressed genes. More importantly, we show that all other normalization methods present severely distorted pictures of the data. By failing to account for biological and technical Poisson noise, many methods systematically predict the lowest expressed genes to be most variable in expression, whereas in reality these genes provide least evidence of true biological variability. In addition, by confounding noise removal with lower-dimensional representation of the data, many methods introduce strong spurious correlations of expression levels with the total UMI count of each cell as well as spurious co-expression of genes.

scholarly journals Aktivitas Antimalaria Daun Gempol (Nauclea orientalis (L.) L) terhadap Plasmodium falciparum

2020 ◽  
Vol 30 (2) ◽  
pp. 135-146
Author(s):  
Mery Budiarti ◽  
Anshary Maruzy ◽  
Nengah Ratri RK ◽  
Endang Brotojoyo
Keyword(s):  
Plasmodium Falciparum ◽  
Antimalarial Activity ◽  
Raw Materials ◽  
Raw Material ◽  
Plant Parts ◽  
Phytochemical Compounds ◽  
Bioactive Potential ◽  
Layer Chromatography ◽  
Selection Of

Abstract The use of gempol (Nauclea orientalis (L.) L) stem as a malaria medicine has been empirically and scientifically proven. This condition encourages exploitation which can lead to scarcity of raw materials. Substitution of plant parts as raw material for medicine is one of the innovations that can be done for the sustainability of the plant species. Leaves are one part of the plant that is often used as a raw material for medicine. The selection of leaves as the main ingredient has many advantages over other parts. Until now, research related to the antimalarial bioactive potential of N. orientalis (L.) L leaves has not been published. Therefore, this study aimed to explore the potential for leaf antimalarial activity as an alternative to substitution of stem parts. The leaf extract of N. orientalis (L.) L was prepared by maceration method with 96% ethanol then fractionation was carried out in stage using hexane, ethyl acetate and methanol as solvents. Antimalarial activity testing was carried out in vitro against Plasmodium falciparum 3D7 and Thin Layer Chromatography (TLC) for screening phytochemical compounds in each sample. The hexane solvent was known to produce the most optimum extract by with a yield of 20%. The antimalarial activity of the hexane (IC 50 1.93 μg/mL) and methanol (IC 3.91 μg/ mL) fractions were classified as ‘very active’ and had a tendency to be able to compete with chloroquine phosphate activity. The potential for antimalarial activity in both samples was influenced by the content of alkaloids, steroids, flavonoids and terpenoids which had been developed as active ingredients for malaria drugs. The results of this study indicate that the leaves of Nauclea orientalis (L.) L have the potential to be developed as an alternative to malaria medicine. Abstrak Pemanfaatan batang gempol (Nauclea orientalis (L.) L) sebagai obat malaria telah terbukti secara empiris dan ilmiah. Kondisi tersebut mendorong terjadinya eksploitasi hingga dapat berujung pada kelangkaan bahan baku. Substitusi bagian tumbuhan sebagai bahan baku obat merupakan salah satu inovasi yang dapat dilakukan untuk keberlanjutan hidup spesies tumbuhan tersebut. Daun merupakan salah satu bagian tumbuhan yang sering digunakan sebagai bahan baku obat. Pemilihan daun sebagai bahan utama memiliki banyak kelebihan dibandingkan bagian lainnya. Penelitian terkait potensi bioaktif antimalaria daun Nauclea orientalis (L.) L hingga saat ini belum dipublikasikan. Oleh karena itu, penelitian ini bertujuan untuk menggali potensi aktivitas antimalaria daun sebagai alternatif subtitusi bagian batang. Ekstrak daun Nauclea orientalis (L.) L disiapkan dengan metode maserasi dengan etanol 96%, kemudian dilakukan fraksinasi cair-cair bertingkat menggunakan pelarut heksana, etil asetat, dan metanol. Pengujian aktivitas antimalaria dilakukan secara in vitro terhadap Plasmodium falciparum 3D7 dan Kromatografi Lapis Tipis (KLT) untuk penapisan senyawa fitokimia pada masingmasing sampel. Pelarut heksana diketahui menghasilkan ekstrak paling optimum dengan rendemen 20%. Aktivitas antimalaria fraksi heksana (IC 50 1,93 µg/mL) dan metanol (IC 3,91 µg/mL) yang tergolong dalam kategori ‘sangat aktif, serta memiliki kecenderungan mampu bersaing dengan aktivitas klorokuin fosfat. Potensi aktivitas antimalaria pada kedua sampel tersebut dipengaruhi oleh kandungan senyawa alkaloid, steroid, flavonoid dan terpenoid yang telah banyak dikembangkan sebagai bahan aktif obat malaria. Hasil penelitian ini menunjukkan bahwa daun Nauclea orientalis (L.) L berpotensi untuk dikembangkan sebagai alternatif obat malaria.

Study of sire selection in view of genetic relation involving fitness traits in Malpura sheep in an organized farm of Rajasthan, India

2017 ◽  
Author(s):  
Govind Mohan ◽  
G. R. Gowane ◽  
Arun Kumar ◽  
A. K. Chakravarthy
Keyword(s):  
Sex Ratio ◽  
Production Parameter ◽  
Replacement Rate ◽  
Genetic Relation ◽  
Production Parameters ◽  
Fitness Traits ◽  
Adaptive Value ◽  
Total Female ◽  
Selection Of ◽  
Sire Selection

The genetics of fitness traits, viz. replacement rate (RR) and selective value (SV) were studied in the flock of Malpura Sheep along the production parameters of the animals. The study was carried out on 10 years records for 2307 lambing sired by 187 sires. Sire wise incidence of replacement traits was as follows: abnormal birth (0.30%), sex ratio (49.98%), mortality (17.26%), culling (15.37%), RR on total lamb basis (33.98%) and RR on female lamb basis (68.44%). The selective value or adaptive value for the flock was 1.37. Sire did not affect abnormal birth, mortality, culling and SV significantly, whereas sire significantly affected sex ratio, and RR on total female lambs born basis. Ranking of the sires for selective value was incoherent with the ranking for production parameters such as age at first service, age at first lambing, weight at first service, productive flock life and longevity. Study indicated that the selection of sires for SV would not bring desired correlated change on any of the production parameter of the animals.

Persoonlikheids eienskappe as voorspellers van die loopbaansukses van provinsiale verkeersbeamptes

2001 ◽  
Vol 27 (3) ◽  
Author(s):  
Andre Geldenhuys ◽  
Delene Visser ◽  
Anne Crafford
Keyword(s):  
Provincial Government ◽  
Free State ◽  
Personality Factor ◽  
Personality Profiles ◽  
Relevant Research ◽  
Selection Decisions ◽  
Effective Selection ◽  
Selection Of ◽  
Urgent Necessity

The effective selection of competent provincial traffic officers has become an urgent necessity for provincial governments. Due to a lack of relevant research on which selection decisions can be based, a study was conducted on a total of 206 respondents from the Free State Provincial Government to determine whether differences exist between the personality profiles of successful and relatively unsuccessful provincial traffic officers. No statistically significant differences were found between the successful and unsuccessful groups on the 16 Personality Factor Questionnaire.Various shortcomings of the study are discussed and recommendations for research suggested. Opsomming Die doeltreffende keuring van bekwame provinsiale verkeersbeamptes het dringend noodsaaklik geword vir provinsiale regerings.Vanwee onvoldoende toepaslike navorsing waarop keuringsbesluite gebaseer kan word, is ’n ondersoek in die Vrystaatse Provinsiale Regering op 206 provinsiale verkeersbeamptes uitgevoer om te bepaal of daar verskille bestaan tussen die persoonlikheidsprofiele van suksesvolle en relatief onsuksesvolle beamptes. Geen statisties beduidende verskille ten opsigte van die faktore van die 16- Persoonlikheidsfaktorvraelys is tussen die suksesvolle en onsuksesvolle groepe gevind nie.Verskeie beperkings van die ondersoek is bespreek en voorstelle vir toekomstige navorsing is gemaak.

scholarly journals Preparative Purification of Recombinant Proteins: Current Status and Future Trends

2013 ◽  
Vol 2013 ◽  
pp. 1-18 ◽  
Author(s):  
Mayank Saraswat ◽  
Luca Musante ◽  
Alessandra Ravidá ◽  
Brian Shortt ◽  
Barry Byrne ◽  
...  
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
Downstream Processing ◽  
Current Status ◽  
Comprehensive Overview ◽  
Two Phase ◽  
Phase Partitioning ◽  
Absolute Requirement ◽  
Flow Filtration ◽  
Selection Of

Advances in fermentation technologies have resulted in the production of increased yields of proteins of economic, biopharmaceutical, and medicinal importance. Consequently, there is an absolute requirement for the development of rapid, cost-effective methodologies which facilitate the purification of such products in the absence of contaminants, such as superfluous proteins and endotoxins. Here, we provide a comprehensive overview of a selection of key purification methodologies currently being applied in both academic and industrial settings and discuss how innovative and effective protocols such as aqueous two-phase partitioning, membrane chromatography, and high-performance tangential flow filtration may be applied independently of or in conjunction with more traditional protocols for downstream processing applications.

Melt-spun talc-filled polypropylene fibers and yarns with higher thermal shock resistance

2016 ◽  
Vol 87 (1) ◽  
pp. 31-45
Author(s):  
Mevlut Tascan ◽  
Serkan Nohut
Keyword(s):  
Tensile Strength ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Polypropylene Fibers ◽  
Main Motivation ◽  
Production Parameters ◽  
Melt Spun ◽  
Shock Resistance ◽  
Talc Particle ◽  
Selection Of

An increase in the application areas of textiles has resulted in the need for improved and additional properties and functions, which should be provided by polymers with different functionalities or the addition of particles to the fibers. In the framework of this study, microsized talc particle-filled polypropylene (PP) fibers and yarns were produced and the mechanical, physical and thermal properties of the fibers and yarns were analyzed with respect to production parameters. The main motivation of the selection of talc as the filler material is to improve the thermal shock resistance and decrease the shrinkage of PP fibers and yarns. As a result of experimentation, it was observed that an increase of talc ratio decreases the tensile strength of fibers and yarns. However, this reduction does not seem to be an obstacle to produce fabrics. Furthermore, the addition of microsized talc particles in PP yarns dramatically improved thermal shock resistance and helped to decrease the shrinkage of these yarns.

scholarly journals Biased competition in the absence of input bias revealed through corticostriatal computation

2019 ◽  
Vol 116 (17) ◽  
pp. 8564-8569 ◽  
Author(s):  
Salva Ardid ◽  
Jason S. Sherfey ◽  
Michelle M. McCarthy ◽  
Joachim Hass ◽  
Benjamin R. Pittman-Polletta ◽  
...  
Keyword(s):  
Firing Rate ◽  
Rhythmic Activity ◽  
High Strength ◽  
Downstream Processing ◽  
Projection Neurons ◽  
Biased Competition ◽  
Cortical Input ◽  
Neuronal Ensembles ◽  
Input Strength ◽  
Selection Of

Classical accounts of biased competition require an input bias to resolve the competition between neuronal ensembles driving downstream processing. However, flexible and reliable selection of behaviorally relevant ensembles can occur with unbiased stimulation: striatal D1 and D2 spiny projection neurons (SPNs) receive balanced cortical input, yet their activity determines the choice between GO and NO-GO pathways in the basal ganglia. We here present a corticostriatal model identifying three mechanisms that rely on physiological asymmetries to effect rate- and time-coded biased competition in the presence of balanced inputs. First, tonic input strength determines which one of the two SPN phenotypes exhibits a higher mean firing rate. Second, low-strength oscillatory inputs induce higher firing rate in D2 SPNs but higher coherence between D1 SPNs. Third, high-strength inputs oscillating at distinct frequencies can preferentially activate D1 or D2 SPN populations. Of these mechanisms, only the latter accommodates observed rhythmic activity supporting rule-based decision making in prefrontal cortex.

scholarly journals Analysis of Carbon Neutrality Programmes in the  International Market

2021 ◽  
Author(s):  
◽  
Robert Mitchell
Keyword(s):  
Literature Review ◽  
Information Asymmetry ◽  
Adverse Selection ◽  
Service Providers ◽  
Market Failures ◽  
Environmental Reporting ◽  
Carbon Neutrality ◽  
Potential Market ◽  
Carbon Neutral ◽  
Selection Of

<p>Carbon Neutrality is a new concept that lacks a broadly accepted definition. There are diverse definitions and many different carbon neutrality programmes available in the market. The availability of so many diverse definitions and programmes can create confusion about what consumers are buying and whether or not it is of a reasonable level of quality. This thesis's aim was to analyse a selection of programmes from the Carbon Neutrality market to gain a greater understanding of content, process, and criteria that comprise carbon programmes. As there was a lack of literature available on Carbon Neutrality; this thesis developed a series of criteria that were developed from a literature review of the broader literature of environmental. The literature review focused on potential market failures, environmental reporting and eco-labels, which identified issues such as information asymmetry, lack of transparency, and adverse selection. Of the Carbon Neutrality service providers asked to participate in this thesis, the majority declined, as a result two were analysed; The Carbon Neutral Company, and CarbonZero. The analysis showed that the programmes use many, but not all, of the criteria identified by this thesis as necessary to provide accurate and comprehensive Carbon Neutral accreditation. The programmes varied in their definitions of what is Carbon Neutrality. This was illustrated by which sections of their programmes were voluntary and which were mandatory. This thesis came to the conclusion that as an undeveloped market there are issues around what should be included in a programme. The criteria developed by this thesis also have the potential to be used for analysing environmental reporting standards and eco-labels. Furthermore methods of communicating a programme's content and the outcome of CN accreditation varied, exhibiting both positive and negative aspects addressing issues such as information asymmetry and adverse selection.</p>

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