scholarly journals TIME OF RECOMBINATION IN THE DROSOPHILA MELANOGASTER OOCYTE. III. SELECTION AND CHARACTERIZATION OF TEMPERATURE-SENSITIVE AND -INSENSITIVE, RECOMBINATION-DEFICIENT ALLELES IN DROSOPHILA

Genetics ◽  
1984 ◽  
Vol 108 (2) ◽  
pp. 425-443
Author(s):  
R F Grell
Keyword(s):  
Gene Dosage ◽  
Temperature Response ◽  
Sharp Decrease ◽  
The Other ◽  
Temperature Sensitive ◽  
Response Curves ◽  
Chromosome Arm ◽  
Complex Locus ◽  
Selection Of

ABSTRACT The procedure for the selection of a temperature-sensitive recombination mutant in Drosophila is described. Use of this procedure has led to the recovery of three alleles at a new recombination locus called rec-1, located within the region of chromosome 3 circumscribed by Deficiency(3R)sbd  105. One allele, rec-1  26, is temperature sensitive, and the other two alleles, rec-1  6 and rec-1  16, are temperature insensitive. Gene dosage studies reveal rec-1  26 to be a leaky mutant with greater recombination activity in two doses than in one. The other two alleles show no dose response, implying that they may be null mutants. The temperature response curves of rec-1  26 as a homozygote and in heteroallelic combination with rec-1  16 suggest that the sharp decrease in recombination between 28° and 31° indicates temperature denaturation of an enzyme or other protein specified by the mutant and associated with the recombination process. The ability of small changes in temperature to reverse or abolish polarity in recombination along the X chromosome arm in rec-1  26/rec-1  16 females brings into question the use of the "polarity" criterion to partition mutants into two functional types, i.e., precondition mutants that display polarity and exchange mutants that do not. Evidence that rec-1 may be part of a complex locus residing in a chromosome segment harboring a variety of recombination-related genes is presented.

scholarly journals Selection of Unusual Actinomycetal Primary σ70 Factors by Plant-Colonizing Frankia Strains

2004 ◽  
Vol 70 (2) ◽  
pp. 991-998 ◽  
Author(s):  
Céline Lavire ◽  
Didier Blaha ◽  
Benoit Cournoyer
Keyword(s):  
Growth Conditions ◽  
Infection Process ◽  
The Other ◽  
Gene Library ◽  
Pcr Screening ◽  
Liquid Cultures ◽  
Total Dna ◽  
Root Hair Infection ◽  
Selection Of

ABSTRACT Functional adaptations of σ70 transcriptional factors led to the emergence of several paralogous lineages, each one being specialized for gene transcription under particular growth conditions. Screening of a Frankia strain EaI-12 gene library by σ70 DNA probing allowed the detection and characterization of a novel actinomycetal primary (housekeeping) σ70 factor. Phylogenetic analysis positioned this factor in the RpoD cluster of proteobacterial and low-G+C-content gram-positive factors, a cluster previously free of any actinobacterial sequences. σ70 DNA probing of Frankia total DNA blots and PCR screening detected one or two rpoD-like DNA regions per species. rpoD matched the conserved region in all of the species tested. The other region was found to contain sigA, an alternative primary factor. sigA appeared to be strictly distributed among Frankia species infecting plants by the root hair infection process. Both genes were transcribed by Frankia strain ACN14a grown in liquid cultures. The molecular phylogeny of the σ70 family determined with Frankia sequences showed that the alternative actinomycetal factors and the essential ones belonged to the same radiation. At least seven distinct paralogous lineages were observed among this radiation, and gene transfers were detected in the HrdB actinomycetal lineage.

scholarly journals Development and Characterization of Cornstarch-Based Bioplastics Packaging Film Using a Combination of Different Plasticizers

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3487
Author(s):  
Walid Abotbina ◽  
S. M. Sapuan ◽  
M. T. H. Sultan ◽  
M. F. M. Alkbir ◽  
R. A. Ilyas
Keyword(s):  
Tensile Strength ◽  
Moisture Content ◽  
Water Absorption ◽  
Food Packaging ◽  
The Other ◽  
Packaging Film ◽  
Film Properties ◽  
Selection Of

This work aims to develop cornstarch (CS) based films using fructose (F), glycerol (G), and their combination (FG) as plasticizers with different ratios for food packaging applications. The findings showed that F-plasticized film had the lowest moisture content, highest crystallinity among all films, and exhibited the highest tensile strength and thermostability. In contrast, G-plasticized films showed the lowest density and water absorption with less crystallinity compared to the control and the other plasticized film. In addition, SEM results indicated that FG-plasticized films had a relatively smoother and more coherent surface among the tested films. The findings have also shown that varying the concentration of the plasticizers significantly affected the different properties of the plasticized films. Therefore, the selection of a suitable plasticizer at an appropriate concentration may significantly optimize film properties to promote the utilization of CS films for food packaging applications.

scholarly journals SIMULATION OF THE TEMPERATURE PROFILE OF A PECTIN SOLUTION IN A PLATE HEAT EXCHANGER: A NON-LINEAR SYSTEM APPROACH FOR CONTROL

2005 ◽  
Vol 4 (1) ◽  
Author(s):  
M. R. Scariot ◽  
M. I. Berto ◽  
V. Silveira
Keyword(s):  
Heat Exchanger ◽  
Temperature Profile ◽  
Temperature Response ◽  
Plate Heat Exchanger ◽  
Response Curves ◽  
Plate Heat ◽  
Linear Behavior ◽  
Non Linear ◽  
Non Linear System

Experimental measurement can be made only of inlet and outlet global temperature of plate heat exchanger (PHE), therefore the temperature profile along of a PHE is hardly ever known. The goal of this work was to evaluate the influence of a non-Newtonian behavior of pectin solution in the temperature response curves along of the PHE. The results were obtained using a simulation codified in Matlab 6.1 software. The response curves resulted from the simulations were fitted to models for identification and characterization of the system linearity. The result shows a clear non-linear behavior of the response curves along the PHE.

scholarly journals SIMULATION OF THE TEMPERATURE PROFILE OF A PECTIN SOLUTION IN A PLATE HEAT EXCHANGER: A NON-LINEAR SYSTEM APPROACH FOR CONTROL

2005 ◽  
Vol 4 (1) ◽  
pp. 30
Author(s):  
M. R. Scariot ◽  
M. I. Berto ◽  
V. Silveira
Keyword(s):  
Heat Exchanger ◽  
Temperature Profile ◽  
Temperature Response ◽  
Plate Heat Exchanger ◽  
Response Curves ◽  
Plate Heat ◽  
Linear Behavior ◽  
Non Linear ◽  
Non Linear System

Experimental measurement can be made only of inlet and outlet global temperature of plate heat exchanger (PHE), therefore the temperature profile along of a PHE is hardly ever known. The goal of this work was to evaluate the influence of a non-Newtonian behavior of pectin solution in the temperature response curves along of the PHE. The results were obtained using a simulation codified in Matlab 6.1 software. The response curves resulted from the simulations were fitted to models for identification and characterization of the system linearity. The result shows a clear non-linear behavior of the response curves along the PHE.

scholarly journals RECOVERY AND CHARACTERIZATION OF TEMPERATURE-SENSITIVE MUTATIONS AFFECTING ADULT VIABILITY IN DROSOPHILA MELANOGASTER

Genetics ◽  
1986 ◽  
Vol 113 (2) ◽  
pp. 367-389
Author(s):  
Theodore Homyk ◽  
Donald A R Sinclair ◽  
David T L Wong ◽  
Thomas A Grigliatti
Keyword(s):  
Temperature Shift ◽  
The Other ◽  
Temperature Sensitive ◽  
Cell Type ◽  
Lethal Mutations ◽  
Preimaginal Development ◽  
Depth Analysis ◽  
Mosaic Analysis ◽  
Developmental Analysis

ABSTRACT Temperature-sensitive (ts) autonomous cell-lethal mutations have been used extensively to study important developmental phenomena, such as pattern formation, in Drosophila. Their utility would be enhanced considerably if it were possible to establish which cell type is primarily affected by each lesion. To facilitate such an approach we have isolated and characterized 21 EMS- induced X-linked adult-lethal (adl) mutants, 16 of which are ts. Most of these lesions also elicit ts lethal effects during preimaginal development. They represent 19 different loci distributed randomly along the X chromosome. The general properties of these mutations are described. In addition, results of an in-depth analysis (focus mapping and, in some cases, temperature shift and heat-pulse studies) of four strains, adl-1ts  1, sesE, adl-2ts  1 and rex are reported. Two major temperature-sensitive periods (TSPs) of adl-1 lethality were resolved: one during the second half of embryogenesis and the other coinciding with pupariation. Mosaic analysis revealed separate mesodermal foci for leg paralysis. Developmental analysis of adl-1 embryos suggest that the adl-1 product may be required for maintenance of muscle tissue. Two discrete TSPs of sesE lethality exist: one during the second instar and the other extending from late third instar to early pupation. Mosaic analysis of sesE lethality resolved a pair of neural foci, each of which appears to incorporate three separate foci for leg paralysis. Mosaic analysis of adl-2ts  1 revealed the existence of paired lethal foci that appear to map to the vicinity of the subesophageal ganglion. Analysis of rex mosaics resolved separate mesodermal foci for leg paralysis.

scholarly journals INTERNATIONAL STANDARDS FOR THE FORMATION OF THE CORPS OF JUDGES AS THE BASIS OF IMPROVING THE GUARANTEES OF INDEPENDENCE OF THE COURT AND JUDGES

2020 ◽  
pp. 52-56
Author(s):  
P. V. Horinov
Keyword(s):  
International Standards ◽  
The Other ◽  
Court Cases ◽  
General Characterization ◽  
Administrative Procedures ◽  
The Subject ◽  
The Law ◽  
Selection Of

The article is devoted to the general characterization of the international standards for the formation of the corps of judges and the corresponding administrative procedures as a basis for improving the guarantees of independence of the court and judges, to determine on this basis the key ways of introducing these standards into the domestic system of legislation in order to resolve specific and specific other issues. It is substantiated that it is expedient to organize the international standards of formation of the corps of judges in the context of guaranteeing the independence of the court and judges according to the criterion of the object of their influence. According to this criterion, standards were identified concerning: recruitment of judges; staffing the subject of appointment of judges to positions; training of judges; guarantees during the service. In the course of the study, it was determined that in order to specify the notion of substantial disciplinary misconduct as a circumstance, which makes it impossible to appoint a judge, it is advisable to amend the Law «Оn the Judiciary and Status of Judges»: to supplement part 4 of Article 69 with paragraph 2, in which to specify the notion of substantial discipline misdemeanor as a circumstance, which makes it impossible to appoint a judge; amend Article 69, paragraph 4, after the words «for committing a material disciplinary offense» by the words «except as provided in the second paragraph of this paragraph». There are two ways to implement international standards in the work of the judiciary on the formation of a corps ofjudges. The first is the transfer of some of the powers of the High Qualifications Commission of Judges of Ukraine (including the selection of judges to the post) to the competence of the High Council of Justice. In the other part of its authority, the High Qualifications Commission of Judges of Ukraine must remain in charge of the judicial self-government bodies. The second is the complete retention of the relevant powers under the High Qualifications Commission of Judges of Ukraine, leaving the issue of the formation of the High Qualifications Commission of Judges of Ukraine within the jurisdiction of judicial self-governing bodies. The first way is recommended. In the course of the research, it was determined that guarantees of independence of the judiciary are purely practical categories. Actually enshrining them in the legislation will not guarantee the independence of the judicial branch of power, and in particular − the independence of judges in the resolution of court cases. Such guarantees only work if they are actually secured.

scholarly journals Selection of SHV Extended-Spectrum-β-Lactamase-Dependent Cefotaxime and Ceftazidime Resistance in Klebsiella pneumoniae Requires a Plasmid-Borne blaSHV Gene

2007 ◽  
Vol 52 (2) ◽  
pp. 441-445 ◽  
Author(s):  
David S. Hammond ◽  
Tegan Harris ◽  
Jan Bell ◽  
John Turnidge ◽  
Philip M. Giffard
Keyword(s):  
Klebsiella Pneumoniae ◽  
Copy Number ◽  
Gene Dosage ◽  
Single Cells ◽  
The Other ◽  
Gene Dosage Effects ◽  
Dosage Effects ◽  
Extended Spectrum ◽  
Copy Number Amplification ◽  
Selection Of

ABSTRACT In Klebsiella pneumoniae, it is common for plasmid-located and chromosome-located bla SHV copies to coexist within single cells. The plasmid-borne genes are mainly derived from two separate IS26-mediated mobilizations of bla SHV. The objective of this study was to test the hypothesis that the presence of a non-extended-spectrum β-lactamase (non-ESBL) encoding plasmid-borne form of bla SHV facilitates the cefotaxime (CTX)-mediated selection of ESBL-expressing mutants, even when there is a chromosomal copy of the same gene. Twenty-one diverse ESBL-negative, bla TEM-negative K. pneumoniae clinical isolates were tested for the IS26 insertions characteristic of the two mobilization events. The isolates were then tested for their ability to be selected for ESBL-mediated CTX resistance by serial subculturing with a doubling of the CTX concentration at every subculture. Fourteen isolates possessed neither of the IS26 insertions. None of these became ESBL positive, and all died during the course of the experiment, despite possessing chromosomal bla SHV copies. The other isolates all became ESBL positive and grew abundantly up to a CTX concentration of 128 μg/ml. Similar results were obtained with ceftazidime. ESBL expression was associated with the appearance of the expected G→A mutation at position 1 of codon 238 and also with bla SHV copy number amplification. It was concluded that plasmid-borne bla SHV greatly facilitates the selection of ESBL expression, even when the same gene is on the chromosome, and that gene dosage effects are likely to contribute to this phenomenon.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

A very rapid in situ Kikuchi technique to determine relative crystal misorientation

1988 ◽  
Vol 46 ◽  
pp. 830-831
Author(s):  
J. I. Bennetch
Keyword(s):  
Electron Beam ◽  
Analytical Techniques ◽  
Superplastic Forming ◽  
The Other ◽  
Kikuchi Pattern ◽  
Kikuchi Line ◽  
Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

Applications of Transmission Electron Microscopy in the Characterization of Metal Machinability

1968 ◽  
Vol 26 ◽  
pp. 442-443 ◽  
Author(s):  
L.E. Murr ◽  
A.B. Draper
Keyword(s):  
Electron Microscopy ◽  
State Physics ◽  
Test Material ◽  
Milling Machine ◽  
Rotary Table ◽  
Solid State Physics ◽  
Materials Properties ◽  
Transmission Electron ◽  
Selection Of

The industrial characterization of the machinability of metals and alloys has always been a very arbitrarily defined property, subject to the selection of various reference or test materials; and the adoption of rather naive and misleading interpretations and standards. However, it seems reasonable to assume that with the present state of knowledge of materials properties, and the current theories of solid state physics, more basic guidelines for machinability characterization might be established on the basis of the residual machined microstructures. This approach was originally pursued by Draper; and our presentation here will simply reflect an exposition and extension of this research.The technique consists initially in the production of machined chips of a desired test material on a horizontal milling machine with the workpiece (specimen) mounted on a rotary table vice. A single cut of a specified depth is taken from the workpiece (0.25 in. wide) each at a new tool location.

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