bluuebunny/crossref_metadata_2025_split huggingface dataset:
Date Palm fibre reinforced composite by multiple resin to enhance the properties of a composite - A Review
Authors: Rajan Rajthilak Krishnan , Ramesh S , Lokesh G.N. , Boppana Satish Babu 
Published: January 2021

Abstract
Numerous applications of the composites have been increased in this Era. The Research on polymer matrix composites using Natural fibre is wide. Natural fibres are one of the most abundant resources that exist in nature. In this paper, Date palm fibre is discussed for making of composites as it is one of the most available natural fibres in the world. It is the basic agricultural crop, especially in Middle East countries. Specific strength is the Parameter which makes date palm fibre superior compared to other fibres. To improve proper adhesion, the natural fibres are to be chemically treated to attain the better properties when compared to the untreated fibres. However, resins play a vital role in preparing a Composite. There are multiple resins used as matrices to make a composite. Hence, this paper is to analyse the date palm fibre-based polymer matrix composites for different resins for their Mechanical properties and Thermal properties. The Properties of various Natural fibres are also discussed in this paper.
Design of Parallel Sorting System Using Discrete-Time Neural Circuit Model
Authors: Tymoshchuk Pavlo V 
Published: January 2021

Abstract
A parallel sorting system based on discrete-time K-Winners-Take-All (KWTA) neural circuit (NC) model is designed. The system is described by a set of difference equations and by step functions. The KWTA NC model of discrete-time is given by difference equation and by step functions. Corresponding functional block-diagrams of the system are presented. The upper limit on the number of iterations required to achieve a convergence of the sorting process to the steady state is defined. The system does not need a knowledge of range of input data change. In order to use the system, the minimal difference between the inputs should be known. The system is suitable for processing unknown inputs of finite values located in arbitrary unknown finite range. The system is characterized by arbitrary finite resolution of inputs, high speed, moderate computational complexity and complexity of software implementation. The results of computer simulations illustrating efficiency of the system are provided.
Development and Modeling of Remote Laboratory Works for Engineering Education
Authors: Sus B B , Zagorodnyuk S P , Bauzha O S , Kozinetz A 
Published: January 2021

Abstract
The basic principles of finite-state machine synthesis and simulation on Proteus CAD and VHDL are discussed. The main steps of designing an electronic circuit of the control and operating finite-state machines that perform the calculation of a given algebraic expression were described. The main steps of consistent performance of a complex task for the development of cross-cutting knowledge and skills, which must be performed by the student in the framework of the normative discipline ware analysed in detail. It is shown that the developed cycle of laboratory works can be successfully implemented in various training courses.
Design Model for Determination of the Strength Fiber-Reinforced Concrete
Authors: Sylovanyuk Viktor , Lisnichuk Riy , Kolesnyk Kostiantyn , Panchak Roman 
Published: January 2021

Abstract
The model of fiber-reinforced concrete for determination of strength under tensile was developed. Formula for assessment of the strength of fiber-reinforced concrete, which takes into account micro-cracks and pores in the materials structure and the presence of reinforcing fibers, was established on the basis of the model. Experimental study for establishment of strength of cement reinforced with fiber of different nature and different volume content were conducted to confirm the received formula. It was shown that theoretical prediction of fiber-reinforced concrete strength correlates with experimental data.
Issues with Belt Guidance and Device Controls in the Automated Conveyor and Drive Belt Perforation Process
Authors: Wojtkowiak D , Talaśka K , Domek G , Wilczyński D , Górecki J 
Published: January 2021

Abstract
The perforation process for multi-layer composite polymer belts presents numerous challenges due to the varied mechanical characteristics and geometrical parameters of the entire range of belts used in the industry. Many problems can be minimized or eliminated with correct development of construction features of the machines for high precision mechanical belt perforation. Regardless of the construction solutions employed in the devices, a major factor influencing the quality of the final product as well as machine reliability is the method of controlling their operation as well as the correct guidance of the belt throughout the entire flow of material in the manufacturing process. The present work provides an analysis of the assemblies ensuring correct belt guidance and presents the causes and effects of incorrect development of these systems. Furthermore, it touches upon the aspects involving the control solutions for such equipment involving the definition of actuators and controllers, the selection of sensors and methods of measuring linear displacement of the belt and perforating head position together with the control algorithms for carrying out different patterns of perforation.
Does Reproducibility Drive Clinical Accuracy?
Authors: Emancipator Kenneth 
Published: January 2021

Abstract

Objectives
To develop a stochastic model relating measurement uncertainty, including reproducibility, to clinical accuracy, as demonstrated by the receiver operating characteristic curve.

Methods
A model is developed based on the symmetric case of the well-known binormal distribution. The overall distribution is partitioned further into analytical and biological components based on assumptions derived from the Cotlove criterion. Explicit mathematical solutions are derived and further verified by Monte Carlo analyses.

Results
The model demonstrates that tests with analytical error that conforms to the classic Cotlove criterion can achieve receiver operating characteristic curves with areas under the curve of 0.68 to 0.76 and Youden indices of 0.26 to 0.38 but have overall agreement for duplicate measurements of only 80% to 82%. Furthermore, the analytically accurate agreement is only 75% to 78%, and the clinically accurate agreement is only 50% to 60%.

Conclusions
The model suggests that assays may have reasonable clinical accuracy despite having reproducibility of less than 85%. Imperfect assays can substantially improve medical decision-making. The findings must be interpreted with caution given the binormal assumptions, but such assumptions are often useful as a first approximation. Practicing pathologists should feel comfortable performing semiquantitative assays shown to have a strong biological association with clinical outcome.
V-pipe: a computational pipeline for assessing viral genetic diversity from high-throughput data
Authors: Posada-Céspedes Susana , Seifert David , Topolsky Ivan , Jablonski Kim Philipp , Metzner Karin J , Beerenwinkel Niko 
Published: January 2021

Abstract

Motivation
High-throughput sequencing technologies are used increasingly not only in viral genomics research but also in clinical surveillance and diagnostics. These technologies facilitate the assessment of the genetic diversity in intra-host virus populations, which affects transmission, virulence and pathogenesis of viral infections. However, there are two major challenges in analysing viral diversity. First, amplification and sequencing errors confound the identification of true biological variants, and second, the large data volumes represent computational limitations.

Results
To support viral high-throughput sequencing studies, we developed V-pipe, a bioinformatics pipeline combining various state-of-the-art statistical models and computational tools for automated end-to-end analyses of raw sequencing reads. V-pipe supports quality control, read mapping and alignment, low-frequency mutation calling, and inference of viral haplotypes. For generating high-quality read alignments, we developed a novel method, called ngshmmalign, based on profile hidden Markov models and tailored to small and highly diverse viral genomes. V-pipe also includes benchmarking functionality providing a standardized environment for comparative evaluations of different pipeline configurations. We demonstrate this capability by assessing the impact of three different read aligners (Bowtie 2, BWA MEM, ngshmmalign) and two different variant callers (LoFreq, ShoRAH) on the performance of calling single-nucleotide variants in intra-host virus populations. V-pipe supports various pipeline configurations and is implemented in a modular fashion to facilitate adaptations to the continuously changing technology landscape.

Availabilityand implementation
V-pipe is freely available at https://github.com/cbg-ethz/V-pipe.

Supplementary information
Supplementary data are available at Bioinformatics online.
Second-site revertants of Escherichia coli trp repressor mutants.
Authors: Klig L S , Oxender D L , Yanofsky C 
Published: January 2021

Abstract
Second-site reversion studies were performed with five missense mutants with defects in the trp repressor of Escherichia coli. These mutants were altered throughout the gene. The same unidirectional mutagen used in the isolation of these mutants, hydroxylamine, was used in reversion studies, to increase the likelihood that the revertants obtained would have second-site changes. Most of the second-site revertants were found to have the same amino acid substitutions detected previously as superrepressor changes. These second-site revertant repressors were more active in vivo than their parental mutant repressors, in the presence or absence of exogenous tryptophan. Apparently superrepressor changes at many locations in this protein can act globally to increase the activity of mutant repressors.
Structure and evolution of the Adh genes of Drosophila mojavensis.
Authors: Atkinson P W , Mills L E , Starmer W T , Sullivan D T 
Published: January 2021

Abstract
The nucleotide sequence of the Adh region of Drosophila mojavensis has been completed and the region found to contain a pseudogene, Adh-2 and Adh-1 arranged in that order. Comparison of the sequence divergence of these genes to one another and to the Adh region of Drosophila mulleri and other species has allowed the development of a model for the evolution of the duplication of the Adh genes. There have been two major events. An initial duplication of an Adh gene whose dual promoter structure was similar to Drosophila melanogaster, resulted in a species with two Adh genes, one of which may have had only a proximal promoter. A second duplication of this gene generated an Adh region containing three genes. It is proposed that one of these is the ancestral gene having dual promoters, while the other two possess only proximal promoters. Subsequent events have resulted in both a change in the regulation of Adh-2 such that it is expressed as if it had a "distal" type promoter and the mutational inactivation of the most upstream gene resulting in the creation of a pseudogene. The sequence of the D. mojavensis Adh region has also revealed the presence of an element which is composed of juxtaposed inverted imperfectly repeated elements. There is a surprising and not fully explainable strong similarity of the nucleotide sequence of the 5' flanking region of the pseudogene in D. mojavensis and D. mulleri.
The alcohol dehydrogenase polymorphism in Drosophila melanogaster: fitness measurements and predictions under conditions with no alcohol stress.
Authors: Bijlsma-Meeles E , Bijlsma R 
Published: January 2021

Abstract
The relative fitnesses of the different Adh genotypes under normal laboratory conditions and in the absence of alcohol stress were estimated in Drosophila melanogaster according to Prout's method. The larval component (viability) did not reveal fitness differences between the genotypes but for the adult component significant differences were observed. The female adult component (fecundity) showed an overdominant pattern: both homozygous genotypes showed a relative fitness significantly lower than the heterozygous genotype. For the male adult component (virility) also differences were observed. The homozygous SS genotype showed a lower relative fitness than the other two genotypes. Predictions for gene frequency changes based on the estimated fitness values do show a reasonably good correspondence with frequency changes actually observed in a number of experimental cage populations and indicate a globally stable equilibrium around a frequency of the F allele of 0.40-0.70. The relevance of these fitness estimates, obtained under conditions with no alcohol stress, for the explanation of the Adh polymorphisms observed in nature is discussed.
Recombination within a subclass of restriction fragment length polymorphisms may help link classical and molecular genetics.
Authors: Meagher R B , McLean M D , Arnold J 
Published: January 2021

Abstract
Restriction fragment length polymorphisms (RFLPs) are being used to construct complete linkage maps for many eukaryotic genomes. These RFLP maps can be used to predict the inheritance of important phenotypic loci and will assist in the molecular cloning of linked gene(s) which affect phenotypes of scientific, medical and agronomic importance. However, genetic linkage implies very little about the actual physical distances between loci. An assay is described which uses genetic recombinants to measure physical distance from a DNA probe to linked phenotypic loci. We have defined the subset of all RFLPs which have polymorphic restriction sites at both ends as class II RFLPs. The frequency of class II RFLPs is computed as a function of sequence divergence and total RFLP frequency for highly divergent genomes. Useful frequencies exist between organisms which differ by more than 7% in DNA sequence. Recombination within class II RFLPs will produce fragments of novel sizes which can be assayed by pulsed field electrophoresis to estimate physical distance in kilobase pairs between linked RFLP and phenotypic loci. This proposed assay should have particular applications to crop plants where highly divergent and polymorphic species are often genetically compatible and thus, where class II RFLPs will be most frequent.
King's formula for the mutation load with epistasis.
Authors: Kondrashov A S , Crow J F 
Published: January 2021

Abstract
A formula by J. L. King gives the equilibrium mutation load as L = 2 sigma ui(1 - qi)/z - x) in which ui is the mutation rate to deleterious alleles at the ith locus, qi is the frequency of mutant alleles at this locus, x is the mean number of such mutant genes per individual before selection, z is the mean number in individuals eliminated by selection, and the summation is over all relevant loci. We show that this rule is inaccurate for intense selection and that a correct formula is L = 2 sigma ui(1 - qi) w/(z - x) = 2U w/(z - x) = 2U/(z - x + 2U) in which U is the mean number of new mutations per haploid genome in the population and w is the mean relative fitness before selection. If w/(z - x) less than 1/2, the mutation load is less than the Haldane value (U less than or equal to L less than or equal to 2U) and can be considerably less. In a diploid asexual population, however, with independent occurrence of mutations, L = 1 - e-2U regardless of the mode of selection.
Amplification of KP elements associated with the repression of hybrid dysgenesis in Drosophila melanogaster.
Authors: Jackson M S , Black D M , Dover G A 
Published: January 2021

Abstract
Mobile P elements in Drosophila melanogaster cause hybrid dysgenesis if their mobility is not repressed. One type of repression, termed P cytotype, is a complex interaction between chromosomes carrying P elements and cytoplasm and is transmitted through the cytoplasm only of females. Another type of repression is found in worldwide M' strains that contain approximately 30 copies per individual of one particular P element deletion-derivative termed the KP element. This repression is transmitted equally through both sexes. In the present study we show that biparentally transmitted repression increases in magnitude together with a rapid increase in KP copy-number in genotypes starting with one or a few KP elements and no other deletion-derivatives. Such correlated increases in repression and KP number per genome occur only in the presence of complete P elements, supporting the interpretation that they are probably a consequence of the selective advantage enjoyed by flies carrying the highest numbers of KP elements. Analysis of Q strains also reveals the presence of qualitative differences in the way the repression of dysgenesis is transmitted. In general, Q strains not containing KP elements have the P cytotype mode of repression, whereas Q strains with KP elements transmit repression through both sexes. This difference among Q strains further supports the existence of at least two types of repression of P-induced hybrid dysgenesis in natural populations of D. melanogaster.
A CRITICAL EXAMINATION OF THE USE OF THE JOLICOEUR-BRUNEL DIAGRAMS TO DEMONSTRATE SELECTION IN BIOLOGICAL POPULATIONS
Authors: Wool David 
Published: January 2021

ABSTRACT
The use of the Jolicoeur-Brunel hexagonal diagrams to demonstrate selection in biological populations was tested in a computer-simulation study.—The results show convincingly that the probabilities associated with the six deviation patterns illustrated in the hexagonal diagrams are not equal, but depend on the sample size and in particular on the genetic composition of the sampled population. The diagrams thus cannot be used to demonstrate selection, but only to illustrate trends of deviation patterns, which may be real biologically.
AN INVESTIGATION OF THE COMPONENTS OF SEGREGATION-DISTORTER SYSTEMS IN DROSOPHILA MELANOGASTER
Authors: Miklos George L Gabor 
Published: January 2021

ABSTRACT
The problems of the Segregation-Distorter system are approached and unified in terms of an orthodox quantitative genetic system. It is shown that the SD system involves positive and negative modifier genes of varying strengths, that there is no major Stabiliser gene, and that the Activator gene is not unique. It is further argued that the SD phenomenon is mainly male limited, with "female effects" being of small magnitude.
SELECTION IN FINITE POPULATIONS WITH MULTIPLE ALLELES. III. GENETIC DIVERGENCE WITH CENTRIPETAL SELECTION AND MUTATION
Authors: Latter B D H 
Published: January 2021

ABSTRACT
Natural selection for an intermediate level of gene or enzyme activity has been shown to lead to a high frequency of heterotic polymorphisms in populations subject to mutation and random genetic drift. The model assumes a symmetrical spectrum of mutational variation, with the majority of variants having only minor effects on the probability of survival. Each mutational event produces a variant which is novel to the population. Allelic effects are assumed to be additive on the scale of enzyme activity, heterosis arising whenever a heterozygote has a mean level of activity closer to optimal than that of other genotypes in the population.—A new measure of genetic divergence between populations is proposed, which is readily interpreted genetically, and increases approximately linearly with time under centripetal selection, drift and mutation. The parameter is closely related to the rate of accumulation of mutational changes in a cistron over an evolutionary time span.—A survey of published data concerning polymorphic loci in man and Drosophila suggests than an alternative model, based on the superiority of hybrid molecules, is not of general importance. Thirteen loci giving rise to hybrid zones on electrophoresis have a mean heterozygote frequency of 0.22 ±.06, compared with a value of 0.23 ±.04 for 16 loci classified as producing no hybrid enzyme.
DOSAGE OF THE MATERNAL EFFECT GENE ASSOCIATED WITH THE TUMOROUS-HEAD ABNORMALITY IN DROSOPHILA MELANOGASTER
Authors: Siervogel R M 
Published: January 2021

ABSTRACT
The penetrance of tuh-3 observed in the progeny of triploids with two doses of tuh-1 was not statistically different from that occurring in the progeny of their diploid sisters with two doses. A higher penetrance was observed in the progeny of triploids with three doses of tuh-1 than in the progeny of their diploid sisters with two doses. These observations suggest that the maternal effect responsible for increasing the penetrance of tuh-3, the gene causing the tumorous-head abnormality, is caused by a specific gene product of tuh-1, the maternal-effect allele. In addition there is probably a maternal-effect threshold, lying between amounts produced by one and two doses of tuh-1, below which no increased penetrance of tuh-3 is observed.
CIRCULAR DNA MOLECULES IN THE GENUS DROSOPHILA
Authors: Travaglini E C , Schultz J 
Published: January 2021

ABSTRACT
The satellite DNA's from the embryos of five species of Drosophila (D. melanogaster, D. simulans, D. nasuta, D. virilis and D. hydei) have been analyzed for the presence of closed circular duplex DNA molecules, as determined by CsCl-EBr gradients. Circular DNA molecules were found in every species but D. melanogaster. Analyses of cell fractions from adult Drosophila and organ fractions from Drosophila larvae show that fractions containing mitochondria are highly enriched in these molecules.
MACRONUCLEAR GENETICS OF TETRAHYMENA I. RANDOM DISTRIBUTION OF MACRONUCLEAR GENE COPIES IN T. PYRIFORMIS, SYNGEN 1
Authors: Orias Eduardo , Flacks Miriam 
Published: January 2021

ABSTRACT
The objective of this study was to test the idea that the macronuclear (somatic) genetic information is randomly distributed at each cell division in Tetrahymena pyriformis, syngen 1. We took advantage of a quick and reliable test for the detection of stable vegetative segregants in clones heterozygous for ts2, a heat-sensitive mutation. Clones that originated from cells inferred to contain very few (1-3) copies of the ts2 + allele in their macronuclei were selected for pedigree analysis. Experimental results were compared with the results of a computer simulation of the experiment. Our results are fully consistent with the predictions of the Allen-Nanney-Schensted model concerning the replication and distribution of functional gene copies. This model proposes that the macronucleus contains many functional copies of a given gene that are duplicated once during the cell cycle and are randomly distributed to the two-daughter nuclei. Our work has provided a more sensitive test of the assumption of randomness than was previously available. Our evidence for complete randomness suggests that 45, the effective number of macronuclear gene copies previously inferred from the segregation rate, indeed represents the actual number of copies. This conclusion, coupled with previously available evidence that the macronucleus is approximately 45-ploid, suggests that the segregating genetic units in the macronucleus are in effect haploid. This appears to remove the need to postulate inter-allelic repression to account for the phenomenon of phenotypic assortment. Our results, as well as those of others, also are inconsistent with any simple form of the master-slave hypothesis of Allen and Gibson.