scholarly journals On an algorithmic definition for the components of the minimal cell

2018 ◽  
Author(s):  
Octavio Martínez ◽  
M. Humberto Reyes-Valdés
Keyword(s):  
Cell Survival ◽  
Theoretical Biology ◽  
Minimal Cell ◽  
Algorithmic Approach ◽  
Finite Set ◽  
Cell Components ◽  
Survival And Reproduction ◽  
The Many ◽  
Previous Existence

AbstractLiving cells are highly complex systems comprising a multitude of elements that are engaged in the many convoluted processes observed during the cell cycle. However, not all elements and processes are essential for cell survival and reproduction under steady-state environmental conditions. To distinguish between essential from expendable cell components and thus define the ‘minimal cell’ and the corresponding ‘minimal genome’, we postulate that the synthesis of all cell elements can be represented as a finite set of binary operators, and within this framework we show that cell elements that depend on their previous existence to be synthesized are those that are essential for cell survival. An algorithm to distinguish essential cell elements is presented and demonstrated within an interactome. Data and functions implementing the algorithm are given as supporting information. We expect that this algorithmic approach will lead to the determination of the complete interactome of the minimal cell, which could then be experimentally validated. The assumptions behind this hypothesis as well as its consequences for experimental and theoretical biology are discussed.

The many faces of STEM in materials science

1991 ◽  
Vol 49 ◽  
pp. 440-441
Author(s):  
John Silcox
Keyword(s):  
Materials Science ◽  
Auger Spectroscopy ◽  
Dark Field ◽  
High Tc Superconductors ◽  
High Tc ◽  
Acoustic Environment ◽  
Electromagnetic Vibration ◽  
The Many ◽  
Serial Mode

Determination of the microstructure and microchemistry of small features often provides the insight needed for the understanding of processes in real materials. In many cases, it is not adequate to use microscopy alone. Microdiffraction and microspectroscopic information such as EELS, X-ray microprobe analysis and Auger spectroscopy can all contribute vital parts of the picture. For a number of reasons, dedicated STEM offers considerable promise as a quantitative instrument. In this paper, we review progress towards effective quantitative use of STEM with illustrations drawn from studies of high Tc superconductors, compound semiconductors and metallization of H-terminated silicon.Intrinsically, STEM is a quantitative instrument. Images are acquired directly by detectors in serial mode which is particularly convenient for digital image acquisition, control and display. The VG HB501A at Cornell has been installed in a particularly stable electromagnetic, vibration and acoustic environment. Care has been paid to achieving UHV conditions (i.e., 10-10 Torr). Finally, it has been interfaced with a VAX 3200 work station by Kirkland. This permits, for example, the acquisition of bright field (or energy loss) images and dark field images simultaneously as quantitative arrays in perfect registration.

Enhanced information from biological materials through technological improvements in cryo-electron microscopy

1992 ◽  
Vol 50 (1) ◽  
pp. 788-789
Author(s):  
Marc J.C. de Jong ◽  
Wim M. Busing ◽  
Max T. Otten
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Biological Materials ◽  
Electron Crystallography ◽  
Cryo Electron Microscopy ◽  
Transmission Electron ◽  
The Many ◽  
Technological Improvements ◽  
Beam Damage

Biological materials damage rapidly in the electron beam, limiting the amount of information that can be obtained in the transmission electron microscope. The discovery that observation at cryo temperatures strongly reduces beam damage (in addition to making it unnecessaiy to use chemical fixatives, dehydration agents and stains, which introduce artefacts) has given an important step forward to preserving the ‘live’ situation and makes it possible to study the relation between function, chemical composition and morphology.Among the many cryo-applications, the most challenging is perhaps the determination of the atomic structure. Henderson and co-workers were able to determine the structure of the purple membrane by electron crystallography, providing an understanding of the membrane's working as a proton pump. As far as understood at present, the main stumbling block in achieving high resolution appears to be a random movement of atoms or molecules in the specimen within a fraction of a second after exposure to the electron beam, which destroys the highest-resolution detail sought.

The Collaborative Medical and Behavioral Management of Chronic Cough

2009 ◽  
Vol 19 (2) ◽  
pp. 49-57
Author(s):  
Brian E. Petty ◽  
Seth H. Dailey
Keyword(s):  
Medical Care ◽  
Chronic Cough ◽  
Therapeutic Management ◽  
Ambulatory Setting ◽  
Behavioral Management ◽  
Speech Language Pathologists ◽  
Speech Language Pathologist ◽  
The Many ◽  
Frequent Reason

Abstract Chronic cough is the most frequent reason cited by patients for seeking medical care in an ambulatory setting and may account for 10% to 38% of a pulmonologist's practice. Because chronic cough can be caused by or correlated with a wide array of disorders and behaviors, the diagnosis of etiologic factors and determination of appropriate therapeutic management in these cases can prove to be daunting for the physician and speech-language pathologist alike. This article will describe the phenomenon of chronic cough, discuss the many etiologic factors to consider, and review some of the more common ways in which speech-language pathologists and physicians collaborate to treat this challenging condition.

The departure of the Greeks from Egypt, 1961: the perspective of Greek diplomacy

2020 ◽  
pp. 1-18
Author(s):  
Evanthis Hatzivassiliou
Keyword(s):  
Near East ◽  
Political Leaders ◽  
The Mediterranean ◽  
Younger Generation ◽  
Post War ◽  
The Many ◽  
Economic Failure

The departure of the greater part of the Greek community from Egypt is one of the many sad stories of the post-war Mediterranean. This article focuses upon the reports of the Greek Consul-General in Alexandria, Byron Theodoropoulos, regarding the Egyptian ‘Socialist Laws’ of summer 1961, which gave the coup de grâce to the Greek community. It argues that the expulsion of the Greeks was part of a wider redistribution of power in the region. This episode, together with similar experiences in other parts of the Mediterranean, evidently cemented the determination of a younger generation of political leaders and diplomats to seek Greece's future in the cosmopolitan, post-nationalist West, rather than in a ‘Near East’ rife with nationalism and economic failure.

scholarly journals A design concept of active cooling for tailored forming workpieces during induction heating

2021 ◽  
Vol 15 (2) ◽  
pp. 177-186
Author(s):  
Caner-Veli Ince ◽  
Anna Chugreeva ◽  
Christoph Böhm ◽  
Fadi Aldakheel ◽  
Johanna Uhe ◽  
...  
Keyword(s):  
Dissimilar Materials ◽  
Heating Process ◽  
Algorithmic Approach ◽  
Cooling Strategy ◽  
Heating And Cooling ◽  
Temperature Constraint ◽  
Inhomogeneous Temperature ◽  
Specific Temperature ◽  
Tailored Forming

AbstractThe demand for lightweight construction is constantly increasing. One approach to meet this challenge is the development of hybrid components made of dissimilar materials. The use of the hybrid construction method for bulk components has a high potential for weight reduction and increased functionality. However, forming workpieces consisting of dissimilar materials requires specific temperature profiles for achieving sufficient formability. This paper deals with the development of a specific heating and cooling strategy to generate an inhomogeneous temperature distribution in hybrid workpieces. Firstly, the heating process boundaries with regard to temperature parameters required for a successful forming are experimentally defined. Secondly, a design based on the obtained cooling strategy is developed. Next a modelling embedded within an electro-thermal framework provides the basis for a numerical determination of admissible cooling rates to fulfil the temperature constraint. Here, the authors illustrate an algorithmic approach for the optimisation of cooling parameters towards an effective minimum, required for applicable forming processes of tailored forming.

Investigation of Radiant Superheater Crossover Pipe Weld Cracking at Big Cajun II Station

2002 ◽  
Author(s):  
James P. King ◽  
Robert D. Hendrix
Keyword(s):  
Growth Curves ◽  
Performance Testing ◽  
Circumferential Welds ◽  
Root Cause ◽  
Ultrasonic Time ◽  
History Of ◽  
The Many ◽  
Stress Fatigue ◽  
Ultrasonic Shear

This paper describes the many features of a detailed investigation into the determination of a root cause for internal cracking found in the circumferential welds of radiant superheater crossover piping lines, in the Units No. 1 and 2 boilers at Big Cajun II Station in New Roads, Louisiana. The history of inside diameter, circumferential cracks dates back to 1992. The cracking had been recorded during several outages for both units. It was discovered by use of ultrasonic shear wave testing, and verified by ultrasonic time of flight diffraction methods. During each of the ensuing unit outages, the crack depths were recorded and mapped. Repairs were undertaken by machining out the complete girth weld followed by re-welding. During the interim years cracking did re-occur at many of the weld locations. In 2000, a detailed investigation into the cause of the cracking was initiated, which resulted in recommendations for resolving the ongoing problem. This detailed study included; nondestructive testing and metallurgy of removed metal samples, boiler performance testing and analysis and stress, fatigue and fracture mechanics evaluations. The detailed background, applications and results of the many and varied testing and analytical tasks are fully described herein. The main conclusion to the root cause of the cracking is identified as fatigue caused by the combined effects of thermal and pressure cycles. Recommendations are given which address the actions needed to limit or prevent re-occurrence of the cracking, including revised boiler operating procedures. In addition, a series of fatigue crack growth curves is presented, as a monitoring toot for evaluating existing cracks in the welds.

scholarly journals Routine Determination of Ice Thickness for Cryo-EM Grids

2018 ◽  
Author(s):  
William J. Rice ◽  
Anchi Cheng ◽  
Alex J. Noble ◽  
Edward T. Eng ◽  
Laura Y. Kim ◽  
...  
Keyword(s):  
Data Collection ◽  
Sample Preparation ◽  
Quality Data ◽  
Ice Thickness ◽  
Limiting Factor ◽  
Test Cases ◽  
Slowing Down ◽  
Routine Monitoring ◽  
The Many

AbstractRecent advances in instrumentation and automation have made cryo-EM a popular method for producing near-atomic resolution structures of a variety of proteins and complexes. Sample preparation is still a limiting factor in collecting high quality data. Thickness of the vitreous ice in which the particles are embedded is one of the many variables that need to be optimized for collection of the highest quality data. Here we present two methods, using either an energy filter or scattering outside the objective aperture, to measure ice thickness for potentially every image collected. Unlike geometrical or tomographic methods, these can be implemented directly in the single particle collection workflow without interrupting or significantly slowing down data collection. We describe the methods as implemented into the Leginon/Appion data collection workflow, along with some examples from test cases. Routine monitoring of ice thickness should prove helpful for optimizing sample preparation, data collection, and data processing.

Use of projects methods in study of second context line of computer science

2021 ◽  
Vol 47 (2) ◽  
pp. 217-223
Author(s):  
A. Azizova ◽  
Keyword(s):  
Computer Science ◽  
Cognitive Abilities ◽  
Functional Model ◽  
Science Research ◽  
Educational Process ◽  
Project Method ◽  
Methodological Research ◽  
The Many ◽  
Procedural Components

The relevance of the topic is justified by the many existing interpretations of the cognitive interest of students. The authors note the lack of scientific and methodological research on the problem of the development of the cognitive abilities in the study of computer science and propose to focus on only one aspect of the research. The aim of the study is to develop the content and procedural components of the educational process using the project method to develop the cognitive interest of students in teaching the omputer science. Research objectives: determination of the psychological and pedagogical foundations of the project method for the development of students' cognitive interests in teaching and studying computer science; development of a structural and functional model of the project; development of a methodology for organizing project activities of students in teaching computer science. The article presents the results of the experiment, which testify to the successful use of the project method in teaching informatics.

Determination of Diazepam (Valium) Concentrations in Serum by Gas—Liquid Chromatography

1970 ◽  
Vol 16 (3) ◽  
pp. 177-179 ◽  
Author(s):  
Lowell B Foster ◽  
Christopher S Frings
Keyword(s):  
Liquid Chromatography ◽  
Chromatographic Method ◽  
Gas Liquid Chromatography ◽  
Gas Chromatograph ◽  
Serum Samples ◽  
The Many ◽  
Gas Chromatographic Method

Abstract A simple, rapid, and precise gas chromatographic method for determination of serum diazepam concentrations is described. Two milliliters of serum is extracted with chloroform, and the extract is concentrated and injected into a gas chromatograph. Of the many drugs and serum samples tested, none interferes with the determination of diazepam.

Multi-scale modeling of cell survival and death mediated by the p53 network: a systems pharmacology framework

2015 ◽  
Vol 11 (11) ◽  
pp. 3011-3021 ◽  
Author(s):  
Yuan Wang ◽  
Zihu Guo ◽  
Xuetong Chen ◽  
Wenjuan Zhang ◽  
Aiping Lu ◽  
...  
Keyword(s):  
Cell Survival ◽  
Cell Fate ◽  
Mammalian Cells ◽  
Regulatory Process ◽  
Systems Pharmacology ◽  
Multi Scale ◽  
Scale Modeling ◽  
Multi Scale Modeling ◽  
P53 Network

The determination of cell fate is a key regulatory process for the development of complex organisms that are controlled by distinct genes in mammalian cells.

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