1,720,987 research outputs found
Multidimensional solid-state NMR spectroscopy of plant cell walls
No full textPlant biomass has become an important source of bio-renewable energy in modern society. The molecular structure of plant cell walls is difficult to characterize by most atomic-resolution techniques due to the insoluble and disordered nature of the cell wall. Solid-state NMR (SSNMR) spectroscopy is uniquely suited for studying native hydrated plant cell walls at the molecular level with chemical resolution. Significant progress has been made in the last five years to elucidate the molecular structures and interactions of cellulose and matrix polysaccharides in plant cell walls. These studies have focused on primary cell walls of growing plants in both the dicotyledonous and grass families, as represented by the model plants Arabidopsis thaliana, Brachypodium distachyon, and Zea mays. To date, these SSNMR results have shown that 1) cellulose, hemicellulose, and pectins form a single network in the primary cell wall; 2) in dicot cell walls, the protein expansin targets the hemicellulose-enriched region of the cellulose microfibril for its wall-loosening function; and 3) primary wall cellulose has polymorphic structures that are distinct from the microbial cellulose structures. This article summarizes these key findings, and points out future directions of investigation to advance our fundamental understanding of plant cell wall structure and function. Keywords:
Cellulose; Matrix polysaccharide; Expansin; Lignin; Magic-angle spinning; Multidimensional correlation; Structural polymorphism; Cellulose-pectin interaction
Barriers Influencing Digital Payment Intention to Adoption by MSME Owners. (Phyo Pyae Sone Win, 2024)
Full text linkThe study mainly focuses on the barriers influencing the intention to adopt
digital payments among MSMEs in the Pathein region. The quantitative research
method was used in this study. The primary data were collected from 283 out of 969
MSME owners with structured questionnaires. The secondary data were sourced from
relevant textbooks, digital payment reports, previously conducted research papers,
internet websites, and articles on Linkedin. This survey focuses on 210 MSMEs owners
who already adopted digital payment with barriers. The structured questionnaires used
a 5-point Likert scale to determine the level of agreement with various statements. The
multiple regression analysis was used in this study. According to the result, multiple
regression analysis showed that image and information barriers significantly and
negatively affect digital payment adoption. The continuous adoption of digital
payments among MSME owners cannot be successful if image and information barriers
remain high. Banks and digital payment organizations should prioritize building a
positive image and developing educational campaigns for MSME owners highlighting
digital payments' benefits and security. Additionally, banks and digital payment
organizations should share more information about promotions and the benefits of
adopting digital payments. Bankers and employees should communicate better with
MSME owners and show positive behavior to encourage the continuous adoption of
digital payments
A Study on Food Safety Knowledge, Attitudes and Prictices of Food Vendors in Yangon City( Phyo Pyae Maung, 2024)
Full text linkThis paper aims to study the food safety knowledge, attitudes and practices of
food vendors in Myanmar. The descriptive method is applied by using both primary
data and secondary data. Primary Data are collected through structured
questionnaires, and secondary data are collected from General Administration
Department (GAD), and Yangon City Development Committee (YCDC) and official
websites. The findings of the thesis reveal significant gaps in food safety practices
among street food vendors in Yangon City. Notably, 90% of vendors report never
undergoing medical inspections, highlighting a lack of regulatory oversight. While
86% acknowledge the importance of hand washing after handling money, inconsistent
practices are observed. Access to clean drinking water is reported by 86% of vendors,
yet this does not always translate into safe food handling. The study underscores the
need for targeted training and regulatory frameworks to enhance food safety, protect
public health, and improve the overall quality of street food in the cit
Effects of Pectin Molecular Weight Changes on the Structure, Dynamics, and Polysaccharide Interactions of Primary Cell Walls of
Full text linkSignificant cellulose–pectin interactions in plant cell walls have been reported recently based on 2D ¹³C solid-state NMR spectra of intact cell walls, but how these interactions affect cell growth has not been probed. Here, we characterize two Arabidopsis thaliana lines with altered expression of the POLYGALACTURONASE INVOLVED IN EXPANSION1 (PGX1) gene, which encodes a polygalacturonase that cleaves homogalacturonan (HG). PGX1[superscript AT] plants overexpress PGX1, have HG with lower molecular weight, and grow larger, whereas pgx1-2 knockout plants have HG with higher molecular weight and grow smaller. Quantitative ¹³C solid-state NMR spectra show that PGX1[superscript AT] cell walls have lower galacturonic acid and xylose contents and higher HG methyl esterification than controls, whereas high molecular weight pgx1-2 walls have similar galacturonic acid content and methyl esterification as controls. 1H-transferred ¹³C INEPT spectra indicate that the interfibrillar HG backbones are more aggregated whereas the RG-I side chains are more dispersed in PGX1[superscript AT] cell walls than in pgx1-2 walls. In contrast, the pectins that are close to cellulose become more mobile and have weaker cross peaks with cellulose in PGX1AT walls than in pgx1-2 walls. Together, these results show that polygalacturonase-mediated plant growth is accompanied by increased esterification and decreased cross-linking of HG, increased aggregation of interfibrillar HG, and weaker HG–cellulose interactions. These structural and dynamical differences give molecular insights into how pectins influence wall dynamics during cell growth
Gradients in Wall Mechanics and Polysaccharides along Growing Inflorescence Stems
Full text linkGradients in growth rate and cell wall compliances resemble gradients in pectin properties, suggesting that high growth rate is enabled by hydrated, highly mobile pectins with weak cellulose interactions
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Visual search in business
No full textWith a rapid increasing number of mobile phone users every year, there are also increase in number of technology that help in human society in daily activities using mobile phones. Each smart phone is equipped with a camera that can take high resolution images. With a combination of internet and smart phone’s camera, people can find information about commercial products by taking a photo of the product. This project is focused on the image recognition of 3D deformable objects and performing experiments on the image recognition techniques for its reliability, performance under different scenarios and recognizing accuracy rate.Bachelor of Engineerin
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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