scholarly journals Cyanobacterial Phycobilisomes. Particles from synechocystis 6701 and two pigment mutants

1980 ◽  
Vol 85 (3) ◽  
pp. 558-566 ◽  
Author(s):  
R Williams ◽  
J Gingrich ◽  
A Glazer
Keyword(s):  
White Light ◽  
Unicellular Cyanobacterium ◽  
The Core ◽  
Cell Extracts ◽  
Induced Mutants ◽  
Structural Details ◽  
Core Elements ◽  
Core Particles

The phycobilisomes of the unicellular cyanobacterium Synechocystis 6701, grown in white light, contain C-phycoerythrin, C-phycocyanin, and allophycocyanin in a molar ration of approximately 2:2:1, and in addition, polypeptides of 99, 46, 33.5, 31.5, 30.5, and 27 x 10(3) Daltons, as well as a trace of a approximately 9 x 10(3)-dalton component. Two nitrosoguanidine-induced mutants of this organism produce aberrant phycobilisomes. Crude cell extracts of these mutants, 6701-NTG25 and NTG31, contain phycoerythrin, phycocyanin, and allophycocyanin in a molar ration of 1:5:1:1 and 0.55:0.3:1.0, respectively. The phycobilisomes from both mutants lack the 33.5 x 10(3)-dalton polypeptide. Wile-type phycobilisomes consist of a core composed of an equilateral array of three cylindrical elements surrounded by six rods in a fanlike arrangement. The rods are made up of stacked disks, 11 nm in diameter and 6 nm thick. In phycobilisomes of mutant 6701-NTG25, numerous particles with fewer than six rods are seen. Mutant 6701-NTG31 produces incomplete structures that extend from triangular core particles, through cores with one or two attached rods, to cores with as many as five rods. The structure of the core appears unaltered throughout. The amount of phycocyanin (relative to allophycocyanin) appears to determine the number of rods per core. A common assembly form seen in 6701-NTG31 is the core with two rods attached at opposite sides. From observations of this form, it is concluded that the core elements are cylindrical, with a height of 14 nm and a diameter of 11 nm. No consistently recognizable structural details are evident within the core elements.

scholarly journals Rod substructure in cyanobacterial phycobilisomes: analysis of Synechocystis 6701 mutants low in phycoerythrin.

1982 ◽  
Vol 92 (2) ◽  
pp. 261-268 ◽  
Author(s):  
J C Gingrich ◽  
L K Blaha ◽  
A N Glazer
Keyword(s):  
Quantitative Analysis ◽  
White Light ◽  
Red Light ◽  
Molar Ratio ◽  
Wild Type ◽  
Wild Type Level ◽  
The Core ◽  
Induced Mutants ◽  
Alpha Beta ◽  
Mutant Cells

Synechocystis 6701 phycobilisomes contain phycoerythrin, phycocyanin, and allophycocyanin in a molar ratio of approximately 2:2:1, and other polypeptides of 99-, 46-, 33.5-, 31.5-, 30.5-, and 27-kdaltons. Wild-type phycobilisomes consist of a core of three cylindrical elements in an equilateral array surrounded by a fanlike array of six rods each made up of 3-4 stacked disks. Twelve nitrosoguanidine-induced mutants were isolated which produced phycobilisomes containing between 0 and 53% of the wild-type level of phycoerythrin and grossly altered levels of the 30.5- and 31.5-kdalton polypeptides. Assembly defects in these mutant particles were shown to be limited to the phycoerythrin portions of the rod substructures of the phycobilisome. Quantitative analysis of phycobilisomes from wild-type and mutant cells, grown either in white light or chromatically adapted to red light, indicated a molar ratio of the 30.5- and 31.5-kdalton polypeptides to phycoerythrin of 1:6, i.e., one 30.5- or one 31.5-kdaltons polypeptide per (alpha beta)6 phycoerythrin hexamer. Presence of the phycoerythrin-31.5-kdalton complex in phycobilisomes did not require the presence of the 30.5-kdalton polypeptide. The converse situation was not observed. These and earlier studies (R. C. Williams, J. C. Gingrich, and A. N. Glazer. 1980. J. Cell Biol. 85:558-566) show that the average rod in wild type Synechocystis 6701 phycobilisomes consists of four stacked disk-shaped complexes: phycocyanin (alpha beta)6-27 kdalton, phycocyanin (alpha beta)6-33.5 kdalton, phycoerythrin (alpha beta)6-31.5 kdalton, and phycoerythrin-30.5 kdalton, listed in order starting with the disk proximal to the core.

Imaging of ribosomal RNA-protein interactions by dark-field STEM

1989 ◽  
Vol 47 ◽  
pp. 250-251
Author(s):  
M. Boublik ◽  
V. Mandiyan ◽  
S. Tumminia ◽  
J.F. Hainfeld ◽  
J.S. Wall
Keyword(s):  
Nucleic Acid ◽  
16S Rrna ◽  
Dark Field ◽  
Radius Of Gyration ◽  
Central Domain ◽  
The Core ◽  
16S Rna ◽  
30S Subunit ◽  
Core Particles

Success in protein-free deposition of native nucleic acid molecules from solutions of selected ionic conditions prompted attempts for high resolution imaging of nucleic acid interactions with proteins, not attainable by conventional EM. Since the nucleic acid molecules can be visualized in the dark-field STEM mode without contrasting by heavy atoms, the established linearity between scattering cross-section and molecular weight can be applied to the determination of their molecular mass (M) linear density (M/L), mass distribution and radius of gyration (RG). Determination of these parameters promotes electron microscopic imaging of biological macromolecules by STEM to a quantitative analytical level. This technique is applied to study the mechanism of 16S rRNA folding during the assembly process of the 30S ribosomal subunit of E. coli. The sequential addition of protein S4 which binds to the 5'end of the 16S rRNA and S8 and S15 which bind to the central domain of the molecule leads to a corresponding increase of mass and increased coiling of the 16S rRNA in the core particles. This increased compactness is evident from the decrease in RG values from 114Å to 91Å (in “ribosomal” buffer consisting of 10 mM Hepes pH 7.6, 60 mM KCl, 2 m Mg(OAc)2, 1 mM DTT). The binding of S20, S17 and S7 which interact with the 5'domain, the central domain and the 3'domain, respectively, continues the trend of mass increase. However, the RG values of the core particles exhibit a reverse trend, an increase to 108Å. In addition, the binding of S7 leads to the formation of a globular mass cluster with a diameter of about 115Å and a mass of ∽300 kDa. The rest of the mass, about 330 kDa, remains loosely coiled giving the particle a “medusa-like” appearance. These results provide direct evidence that 16S RNA undergoes significant structural reorganization during the 30S subunit assembly and show that its interactions with the six primary binding proteins are not sufficient for 16S rRNA coiling into particles resembling the native 30S subunit, contrary to what has been reported in the literature.

What is the Core Elements of Social Innovation?

2019 ◽  
Vol 45 ◽  
pp. 83-109
Author(s):  
SangMi Cho ◽  
JongSerl Chun ◽  
SoYoung An ◽  
JiYeon Jung
Keyword(s):  
Social Innovation ◽  
The Core ◽  
Core Elements

Duoethnography: A Polytheoretical Approach to (Re)Storing, (Re)Storying the Meanings That One Gives

2020 ◽  
pp. 396-423
Author(s):  
John Joseph Norris ◽  
Richard D. Sawyer
Keyword(s):  
Social Justice ◽  
Critical Theory ◽  
Third Space ◽  
The Third ◽  
The Core ◽  
Wide Range ◽  
Core Elements ◽  
Feminist Inquiry

This chapter summarizes the advancement of duoethnography throughout its fifteen-year history, employing examples from a variety of topics in education and social justice to provide a wide range of approaches that one may take when conducting a duoethnography. A checklist articulates what its cofounders consider the core elements of duoethnographies, additional features that may or may not be employed and how some studies purporting to be duoethnographies may not be so. The chapter indicates connections between duoethnography and a number of methodological concepts including the third space, the problematics of representation, feminist inquiry, and critical theory using published examples by several duoethnographers.

scholarly journals 178. Implementation of the Core Elements of Antibiotic Stewardship in Nursing Homes – National Healthcare Safety Network (NHSN), 2016–2018

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S96-S96
Author(s):  
Katryna A Gouin ◽  
Sarah Kabbani; Angela Anttila ◽  
Josephine Mak ◽  
Elisabeth Mungai ◽  
Ti Tanissha McCray ◽  
...  
Keyword(s):  
Nursing Homes ◽  
Antibiotic Stewardship ◽  
Care Facility ◽  
Antibiotic Use ◽  
Infection Prevention And Control ◽  
Term Care ◽  
Long Term Care Facility ◽  
The Core ◽  
Use Of Resources ◽  
Core Elements

Abstract Background Since 2016, nursing homes (NHs) enrolled in the Centers for Disease Control and Prevention’s NHSN Long-term Care Facility (LTCF) Component have reported on their implementation of the core elements of antibiotic stewardship. In 2016, 42% of NHs reported implementing all seven core elements. Recent regulations require antibiotic stewardship programs in NHs. The objectives of this analysis were to track national progress in implementation of the core elements and evaluate how time dedicated to infection prevention and control (IPC) is associated with the implementation of the core elements. Methods We used the NHSN LTCF 2016–2018 Annual Surveys to assess NH characteristics and implementation of the core elements, defined as self-reported implementation of at least one corresponding stewardship activity. We reported absolute differences in percent implementation. We used log-binomial regression models to estimate the association between weekly IPC hours and the implementation of all seven core elements, while controlling for confounding by facility characteristics. Results We included 7,506 surveys from 2016–2018. In 2018, 71% of NHs reported implementation of all seven core elements, a 28% increase from 2016 (Fig. 1). The greatest increases in implementation from 2016–2018 were in Education (+19%), Reporting (+18%) and Drug Expertise (+15%) (Fig. 2). Ninety-eight percent of NHs had an individual responsible for antibiotic stewardship activities (Accountability), with 30% indicating that the role was fulfilled by an infection preventionist. Furthermore, 71% of NHs reported pharmacist involvement in improving antibiotic use, an increase of 27% since 2016. NHs that reported at least 20 hours of IPC activity per week were 14% more likely to implement all seven core elements, when controlling for facility ownership and affiliation, 95% CI: (1.07, 1.20). Conclusion NHs reported substantial progress in antibiotic stewardship implementation from 2016–2018. Improvements in accessing drug expertise, providing education and reporting antibiotic use may reflect increased stewardship awareness and use of resources among NH providers under new regulatory requirements. NHs with at least 20 hours dedicated to IPC per week may have greater capacity to implement all core elements. Disclosures All Authors: No reported disclosures

Webside manner: maskless communication

Diagnosis ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ankit Mehta ◽  
Benji K. Mathews
Keyword(s):  
Communication Skills ◽  
Rapid Expansion ◽  
Technical Aspects ◽  
The Core ◽  
Core Elements ◽  
Virtual Visits ◽  
Virtual Platform ◽  
Structured Approach

Abstract Telemedicine has seen a rapid expansion lately, with virtual visits ushering in telediagnosis. Given the shift in the interpersonal and technical aspects of communications in a virtual visit, it is prudent to understand its effect on the patient-provider relationships. A range of interpersonal and communication skills can be utilized during telemedicine consultations in establishing relationships, and reaching a diagnosis. We propose a construct of “webside manner,” a structured approach to ensure the core elements of bedside etiquette are translated into the virtual encounter. This approach entails the totality of any interpersonal exchange on a virtual platform, to ensure a clinician’s presence, empathy and compassion is translated through this medium.

scholarly journals nanocrystals (0 ≤ x ≤ 1): growth, size control and shell formation on β-NaCeF4:Tb core particles

CrystEngComm ◽  
2020 ◽  
Vol 22 (46) ◽  
pp. 8036-8044
Author(s):  
Jannis Wehmeier ◽  
Markus Haase
Keyword(s):  
Size Control ◽  
Lattice Parameters ◽  
Core Material ◽  
Shell Formation ◽  
Shell Material ◽  
Strontium Content ◽  
The Core ◽  
Lighter Lanthanides ◽  
Core Particles

is an interesting shell material for β-NaREF4 particles of the lighter lanthanides (RE = Ce, Pr, Nd), as variation of its strontium content x allows to vary its lattice parameters and match those of the core material.

Wrapping Blocks: A Fun Way to Teach Job Design

2019 ◽  
Vol 5 (2) ◽  
pp. 144-162
Author(s):  
Regina Yanson ◽  
Melissa J. Mann
Keyword(s):  
Resource Management ◽  
Human Resource Management ◽  
Human Resource ◽  
Job Characteristics ◽  
Job Design ◽  
Graduate Level ◽  
Experiential Teaching ◽  
The Core ◽  
Job Characteristics Model ◽  
Core Elements

This article provides an overview of job design and offers an experiential teaching exercise to help students develop a better comprehension of job design and redesign, as well as learn the importance and challenges of such undertakings. Understanding the core elements of job design is especially important because job design serves as the foundational block for a deeper understanding and application of other organizational phenomenon such as the job characteristics model. This exercise is intended for the introductory undergraduate and graduate-level human resource management course as well as any courses covering “staffing.” Additionally, this activity may be used in the undergraduate Principles of Management or associated introductory management class.

scholarly journals Introducing Gamification in the AR-Enhanced Order Picking Process: A Proposed Approach

Logistics ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 14
Author(s):  
Athina G. Bright ◽  
Stavros T. Ponis
Keyword(s):  
Industry 4.0 ◽  
Business Processes ◽  
Cyber Physical Systems ◽  
Order Picking ◽  
Physical Systems ◽  
The Core ◽  
Complex Process ◽  
Core Elements ◽  
Game Elements ◽  
Innovative Industry

In the last decade, the Industry 4.0 concept has introduced automation and cyber-physical systems as the core elements of future logistics, supported by an array of technologies, such as augmented reality (AR) providing the necessary support for the digital transformation of manufacturing and logistics and the smartification and digital refinement of traditional pre-Industry 4.0 processes. This paper studies the influence and the potential of gamification techniques in supporting innovative Industry 4.0-enhanced processes in the contemporary warehouse work ecosystem. Gamification in the workplace aims to motivate the employees and increase their involvement in an activity, while at the same time creating a sense of an everyday different experience rather than a set of repetitive and monotonous tasks. Since the design of such a system is a complex process, the most widespread design frameworks are studied, and the emphasis is on the principal game elements and their connection to mobilization mechanisms. Finally, an initial proposal of a gamification framework to support the AR-enhanced order picking process in contemporary logistics centers is provided with an emphasis on the mechanics of a fair and functional reward system. The proposed approach aims to showcase the potential alignment of business processes to human motivation, respecting the differences between tasks and the workers’ cognitive workload.

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