bluuebunny/crossref_metadata_2025_split huggingface dataset:
ACTIVITY VARIANTS OF ACID PHOSPHATASE-3 AMONG CHROMOSOME 3 INVERSIONS OF DROSOPHILA PSEUDOOBSCURA
Authors: Norman R A , Prakash Satya 
Published: April 2021

ABSTRACT
Allozymes of the Ap-3 locus in Drosophila pseudoobscura show very strong associations with chromosome 3 inversions. The 0.98 electrophoretic allele is associated with the TL, SC, CH and PP gene arrangements, while the 1.00 electrophoretic allele is characteristic of the AR and ST gene arrangements. Variation in relative 0.98 and 1.00 AP-3 allozyme activities of chromosome 3 isogenic strains was examined on acrylamide gels in F1 heterozygotes obtained by crossing these strains individually to a reference strain with a slower 0.87 mobility allozyme. F2 analyses demonstrated that the activity variants cosegregate with the Ap-3 locus. Both 0.98 and 1.00 allelic classes are polymorphic for AP-3 activities. In contrast to the virtual monomorphism for an electrophoretic allele, each inversion is polymorphic for AP-3 activities. These results reveal substantially more genetic differentiation among gene arrangements than is evident from electrophoretic allele comparisons. Strains having the PP arrangement are distinct from TL strains in their AP-3 activity expression, and ST strains have a wider range of variation than AR strains. In contrast, no geographical differentiation is evident for strains from the Bogota population of D. pseudoobscura.
RESPONSE TO DIVERGENT SELECTION FOR NESTING BEHAVIOR IN MUS MUSCULUS
Authors: Lynch Carol Becker 
Published: April 2021

ABSTRACT
Replicated bidirectional selection (with control lines) for nest-building behavior in Mus musculus, where nesting scores consisted of the total weight of cotton pulled through the cage lid during four days of testing, yielded an eight-fold difference between high and low lines after 15 generations of selection. The overall realized heritability pooled across lines and replicates was 0.18 ± 0.02 (0.15 ± 0.03 for high nesting scores and 0.23 ± 0.04 for low nesting scores), or 0.28 ± 0.05 when adjusted for within-family selection. Across the 15 generations and the entire experiment, average body weight and number of infertile matings increased, while average litter size decreased, although these changes were not consistent across lines. Inbreeding could account for average decreases in the fertility traits, but there was also a correlated response to selection, since both high lines showed increased litter size and decreased infertile matings.
THE EFFECTS OF THREE PSO GENES ON INDUCED MUTAGENESIS: A NOVEL CLASS OF MUTATIONALLY DEFECTIVE YEAST
Authors: Cassier C , Chanet R , Henriques J A P , Moustacchi E 
Published: April 2021

ABSTRACT
Reverse and forward mutation, induced by photoaddition of 8-methoxypsoralen (8-MOP) and 3-carbethoxypsoralen (3-CPs) or ultraviolet light (UV), are reduced in three pso mutants of Saccharomyces cerevisiae. The pso1-1 strain exhibits a lower frequency of spontaneous reversion (antimutator) and is almost entirely unaffected by the three agents in both the haploid and diploid states. The pso2-1 strain demonstrates very reduced frequencies of 8-MOP and 3-CPs plus 365 nm radiation-induced mutations in happloid and diploid cells. UV-induced mutations are slightly reduced, whereas survival is almost normal. The pso3-1 strain is mutable by 8-MOP and 3-CPs photoaddition only in the low-dose range. After UV treatment, survival of pso3-1 is nearly normal, whereas the frequencies of induced mutants are diminished as compared to the normal PSO +. An analogue of adenine, 6-N-hydroxyaminopurine, is capable of inducing reversions in wild type, as well as in pso and rad6-1 mutant strains, indicating that this drug may act as a direct mutagen in yeast. The comparison of photoaddition of the bifunctional agent (8-MOP) to that of the monofunctional one (3-CPs) confirms that cross-links, as well as monoadditions, are mutagenic in S. cerevisiae. Repair, of the recombinational type, taking place in diploid cells or in haploid cells in G2 phase leads to higher survival, but appears to be error-free.
GENETICS OF LIFE HISTORY IN DROSOPHILA MELANOGASTER. II. EXPLORATORY SELECTION EXPERIMENTS
Authors: Rose Michael R , Charlesworth Brian 
Published: April 2021

ABSTRACT
Two types of small-scale selection experiments were performed. (1) Artificial selection experiments were performed on age-specific female fecundity. Selection for early fecundity over three generations produced a statistically detectable direct response. There was no detectable indirect response in other life-history characters. Selection for late fecundity over three generations did not produce any detectable direct response. Indirect responses were detected: early egg-laying decreased and longevity increased. (2) Natural selection for late-age fitness components increased late fecundity, female longevity, and the duration of female reproduction, while early fecundity and mean egg-laying rate decreased.
STUDIES OF ESTERASE 6 IN DROSOPHILA MELANOGASTER. VI. EJACULATE COMPETITIVE ABILITIES OF MALES HAVING NULL OR ACTIVE ALLELES
Authors: Gilbert Donald G , Richmond Rollin C 
Published: April 2021

ABSTRACT
Recent studies of the function of the polymorphic seminal fluid enzyme, esterase 6, of Drosophila melanogaster suggested that it may act in the process of sperm displacement (Gilbert, Richmond and Sheehan, 1981a). This report examines the competitive ability of ejaculates from males homozygous for null or active alleles of esterase 6 under three experimental conditions that model aspects of sexual selection affecting males. The results demonstrate no significant difference in ejaculate competition between esterase 6 null or active male types, but marker males used for paternity identification had poorly competitive ejaculates. The proportion of second-male progeny, P 2, used as an index of competition is primarily influenced by second-male genotype and uninfluenced by female genotype. P2 can change with time from remating and be unaffected by different intensities of competition, which suggests a complex ejaculate competition mechanism.
DEVELOPMENTAL STAGES OF GENOME ELIMINATION RESULTING IN TRANSMISSION RATIO DISTORTION OF THE T-007 MALE RECOMBINATION (MR) CHROMOSOME OF DROSOPHILA MELANOGASTER
Authors: Matthews Kathleen A 
Published: April 2021

ABSTRACT
T-007 is a Male Recombination (MR) second chromosome that induces transmission ratio distortion (at its own expense) when heterozygous with many laboratory marker chromosomes. The developmental timing of elimination of T-007 chromosomes has been investigated. About 21% of the T-007 chromosomes expected to be recovered among the progeny of heterozygous T-007 males are lost at some point between fertilization and eclosion (representing 29% of the total distortion observed in young males). Another 52% of the expected number of T-007 chromosomes are lost as a result of spermatid abortion during spermiogenesis (representing 71% of the total distortion). Abnormalities in both the number of spermatids per bundle and the structure of spermatid tails are seen at the earliest stages of spermiogenesis in T-007 males.
GENETICS OF ALDEHYDE DEHYDROGENASE ISOZYMES IN THE MOUSE: EVIDENCE FOR MULTIPLE LOCI AND LOCALIZATION OF Ahd-2 ON CHROMOSOME 19
Authors: Timms Glenn P , Holmes Roger S 
Published: April 2021

ABSTRACT
Electrophoretic and activity variation of the cytoplasmic isozyme of aldehyde dehydrogenase (designated AHD-B4) was observed among inbred strains and Harwell linkage-testing stocks of Mus musculus. The phenotypes are inherited in a normal Mendelian fashion, with two alleles showing co-dominant expression at a single locus (Ahd-2). The locus was shown to segregate independently of Ahd-1 (encoding the mitochondrial AHD-A2 isozymes on chromosome 4; Holmes 1978). Linkage data of Ahd-2 with ep (pale ears), ru (ruby eyes) and bm (brachymorphic) suggest that it is localized near the centromeric end of chromosome 19. Electrophoretic evidence for a third AHD isozyme (designated AHD-Cy), which is predominantly localized in the liver microsomal fraction, is also presented.
GENETIC AND DEVELOPMENTAL ANALYSIS OF A TEMPERATURE-SENSITIVE MINUTE MUTATION OF DROSOPHILA MELANOGASTER
Authors: Sinclair Donald A R , Suzuki David T , Grigliatti Thomas A 
Published: April 2021

ABSTRACT
A temperature-sensitive (ts) third chromosome Minute (M) mutation, designated Q-III, has been recovered and characterized. Q-III heterozygotes raised at 29" exhibit all of the dominant traits of M mutants including small bristles, rough eyes, prolonged development, reduced viability 2nd interactions with several unrelated mutations. Q-III homozygotes raised at 29° are lethal; death occurs primarily during the first larval instar. When raised at 22°, Q-Ill heterozygotes are phenotypically normal and Q-III homozygotes display moderate Mtraits. In addition, Q-IIIelicits ts sterility and maternal-effect lethality. As it true of Mlesions, the dominant traits of Q-111 are not expressed in triploid females raised at 29°. Complementation tests suggest that Q-III is a ts allele of M(3)LS4, which is located in 3L near the centromere.——Reciprocal temperature-shift experiments revealed that the temperature-sensitive period (TSP) of Q-111 lethality is polyphasic, extending from the first instar to the latter half of pupation. Heat-pulse experiments further resolved this into two post-embryonic TSPs: one occurring during the latter half of the second larval instar, and the other extending from the larval/pupal boundary to the second half of pupation. In addition, heat pulses elicited a large number of striking adult phenotypes in Q-III individuals. These included pattern alterations such as deficiencies and duplications and cther morphological defects in structures produced by the eye-antennal, leg, wing and genital imaginal discs and the abdominal histoblasts. Each defect or pattern alteration is associated with a specific TSP during development.——We favor the interpretation that most of the major Q-III defects, particularly the structural duplications and deficiencies, result from temperature-induced cell death in mitotically active imaginal anlagen, while the small macrochaete phene probably results from the direct effects of Q-III on bristle synthesis. The hypothesis that the Q-III locus specifices a component required for protein synthesis is discussed, and it is concluded that this hypothesis can account for the pleiotropy of Q-III, and that perhaps it can be extended to M loci in general.
GENETIC VARIABILITY AT THE ESTERASE-6 LOCUS IN NATURAL POPULATIONS OF DROSOPHILA SIMULANS IN RELATION TO ENVIRONMENTAL HETEROGENEITY
Authors: De Albuquerque Cleide M R , Napp Marly 
Published: April 2021

ABSTRACT
The allozymic variation at the esterase-6 locus was examined in fourteen samples of natural populations of Drosophila simulans collected in two different localities. The samples were collected from different species of fruits in the two localities and from banana baits located some meters apart from the fruits. The analysis was done by sequential electrophoresis, using varied gel concentrations and buffers. By this technique, we detected 27 alleles at the esterase-6 locus, where only five alleles were detected by the usual method. The results obtained suggest that habitat choice alone may not be a selective factor, but may be selective in combination with other environmental factors.
MUTATION-SELECTION BALANCE IN MULTI-LOCUS SYSTEMS. I. DUPLICATE GENE ACTION
Authors: Pritchett-Ewing Evelyn 
Published: April 2021

ABSTRACT
A theoretical model is presented that extends the case of selection against homozygous recessives counterbalanced by mutation to a system of n loci. This extension allows analysis of the role of gene duplication in the evolution of new function. The aspect of retention of function for sufficiently long periods of time to allow for divergence vs. silencing of nonfunctional loci is discussed in relation to examples in salmonid and catastomid fishes and in the globin-like clusters.
GENETIC VARIABILITY MAINTAINED BY MUTATION AND OVERDOMINANT SELECTION IN FINITE POPULATIONS
Authors: Maruyama Takeo , Nei Masatoshi 
Published: April 2021

ABSTRACT
Mathematical properties of the overdominance model with mutation and random genetic drift are studied by using the method of stochastic differential equations (Itô and McKean 1974). It is shown that overdominant selection is very powerful in increasing the mean heterozygosity as compared with neutral mutations, and if 2Ns (N = effective population size; s = selective disadvantage for homozygotes) is larger than 10, a very low mutation rate is sufficient to explain the observed level of allozyme polymorphism. The distribution of heterozygosity for overdominant genes is considerably different from that of neutral mutations, and if the ratio of selection coefficient (s) to mutation rate (ν) is large and the mean heterozygosity (h) is lower than 0.2, single-locus heterozygosity is either approximately 0 or 0.5. If h increases further, however, heterozygosity shows a multiple-peak distribution. Reflecting this type of distribution, the relationship between the mean and variance of heterozygosity is considerably different from that for neutral genes. When s/v is large, the proportion of polymorphic loci increases approximately linearly with mean heterozygosity. The distribution of allele frequencies is also drastically different from that of neutral genes, and generally shows a peak at the intermediate gene frequency. Implications of these results on the maintenance of allozyme polymorphism are discussed.
SELECTIVE ABORTION OF TWO NONSISTER NUCLEI IN A DEVELOPING ASCUS OF THE hfd1—1 MUTANT IN SACCHAROMYCES CEREVISIAE
Authors: Okamoto Susumu , Iino Tetsuo 
Published: April 2021

ABSTRACT
A recessive mutation, hfd1—1, in strain SOS4 of Saccharomyces cerevisiae leads the mutant cells to produce predominantly two-spored asci. Light microscopical examination of Giemsastained cells revealed no significant differences in the meiotic figures between mutant and wild-type strains. However, only two of the four meiotic products in a developing ascus matured to ascospores in SOS4. Dyad analysis was carried out on an hfd1-1 mutant strain heterozygous for three markers, asp5, gal1 and arg4, which are closely linked to their centromeres, and for his4, which is loosely linked to its centromere. The twospored asci produced by the hfd1—1 mutant segregated dominant (+) and recessive (-) alleles of each marker in a 1:1 ratio; they generally contained one + and one - spore for any given marker. The occurrence of rare dyads with two + or two - spores can be explained quantitatively by recombination between the marker and its centromere. From the results of these cytological and genetical analyses, we infer that, in the mutant strain, one genome set is partitioned to each of the four second-meiotic division poles, but only two nonsister genomes are incorporated into mature spores. Thus, the hfd1—1 mutation in SOS4 blocks incorporation of two nonsister nuclei into mature ascospores, but does not block enclosure of the remaining two nonsister nuclei.
Fast Fourier transform of electromagnetic data for computationally expensive kernels
Authors: Werthmüller Dieter , Mulder Wim A , Slob Evert C 
Published: April 2021

SUMMARY
3-D controlled-source electromagnetic data are often computed directly in the domain of interest, either in the frequency domain or in the time domain. Computing it in one domain and transforming it via a Fourier transform to the other domain is a viable alternative. It requires the evaluation of many responses in the computational domain if standard Fourier transforms are used. This can make it prohibitively expensive if the kernel is time-consuming as is the case in 3-D electromagnetic modelling. The speed of modelling obtained through such a transform is defined by three key points: solver, method and implementation of the Fourier transform, and gridding. The faster the solver, the faster modelling will be. It is important that the solver is robust over a wide range of values (frequencies or times). The method should require as few kernel evaluations as possible while remaining robust. As the frequency and time ranges span many orders of magnitude, the required values are ideally equally spaced on a logarithmic scale. The proposed fast method uses either the digital linear filter method or the logarithmic fast Fourier transform together with a careful selection of evaluation points and interpolation. In frequency-to-time domain tests this methodology requires typically 15–20 frequencies to cover a wide range of offsets. The gridding should be frequency- or time-dependent, which is accomplished by making it a function of skin depth. Optimizing for the least number of required cells should be combined with optimizing for computational speed. Looking carefully at these points resulted in much smaller computation times with speedup factors of ten or more over previous methods. A computation in one domain followed by transformation can therefore be an alternative to computation in the other domain domain if the required evaluation points and the corresponding grids are carefully chosen.
Factors influencing sustainability of online platforms for professionals: a mixed-method study in OECD countries
Authors: Hubertus Bessems Kathelijne Maria Hubertus , Simovska Venka , Driessen Willems Marion Daniëlle , Carlsson Monica , de Vries and Nanne K 
Published: April 2021

SummaryOnline platforms can support health and educational professionals in their daily work; however, it is challenging to keep online platforms sustainable. This paper aims to indicate the most important factors of platform sustainability from the perspective of professionals involved in online platforms. Further, it aims to understand how these factors operate. A mixed methods study was carried out among professionals from Europe, Australia, the USA and Canada. In the first phase, the importance of 54 factors from the literature was assessed with a questionnaire among 17 professionals. The relative importance of the factors and the consensus regarding this importance were calculated using median scores and interquartile deviations. In total, 19 factors were selected representing general characteristics, characteristics related to the platform, communication, visitor and context. In the second phase, insight was gained regarding the experiences with those factors through 12 individual Skype interviews. The most frequently mentioned important factors of platform sustainability were (i) having sufficient time, resources and expertise, (ii) user friendliness and (iii) creating a sense of belonging. Platforms should use a planned approach to address a combination of factors directly from platform development. Gaining long-term resources is challenging and should be considered from the start of a project by building partnerships. To promote user friendliness, platforms should be simple, have a clear set-up and provide high-quality tools. Finally, establishing a sense of belonging could be supported by branding and face-to-face networking activities. For all aspects, involving visitors and stakeholders is essential.
Use of a Persona to Support the Interdisciplinary Design of an Assistive Technology for Meal Preparation in Traumatic Brain Injury
Authors: Olivares Marisnel , Pigot Hélène , Bottari Carolina , Lavoie Monica , Zayani Taoufik , Bier Nathalie , Le Dorze Guylaine , Pinard Stéphanie , Le Pevedic Brigitte , Swaine Bonnie , Therriault Pierre-Yves , Thépaut André , Giroux Sylvain 
Published: April 2021

Abstract
User-centered design (UCD) facilitates the creation of technologies that are specifically designed to answer users’ needs. This paper presents the first step of a UCD using a persona, a fictitious character representing the targeted population, which in this case is people having sustained a traumatic brain injury (TBI). The persona is used to better understand the possible interactions of a TBI population with a prototype of a technology that we wish to develop, namely the Cognitive Orthosis for coOKing (COOK). COOK is meant to be an assistive technology that will be designed to promote independence for cooking within a supported-living residence. More specifically, this paper presents the persona’s creation methodology based on the first four phases of the persona’s lifecycle. It also describes how the persona methodology served as a facilitator to initiate an interdisciplinary collaboration between a clinical team and a computer science team. Creation of personas relied on a clinical model (Disability Creation Process) that contextualized the needs of this population and an evaluation tool [Instrumental Activities of Daily Living (IADL) Profile] that presented a wide range of cognitive assistance needs found in this same population. This paper provides an in-depth description of some of the most frequent everyday difficulties experienced by individuals with TBI as well as the persona’s abilities, limitations and social participation during the realization of IADL, and an evaluation of the manifestations of these difficulties during IADL performance as represented through scenarios. The interdisciplinary team used the persona to complete a first description of the interactions of a persona with TBI with COOK. This work is an attempt at offering a communication tool, the persona, to facilitate interdisciplinary research among diverse disciplines who wish to learn to develop a common language, models and methodologies at the beginning of the design process.
Staphylococcal cassette chromosome mec containing a novel mec gene complex, B4
Authors: Sabat Artur J , Bathoorn Erik , Becker Karsten , Akkerboom Viktoria , Miskoski Madalina , Durfee Tim , Friedrich Alexander W 
Published: April 2021

Abstract

Objectives
To describe a new subclass of mec class B complex identified in Staphylococcus epidermidis.

Methods
Four S. epidermidis isolates obtained from bloodstream infections in patients at University Medical Center Groningen (UMCG) were analysed by phenotypic antibiotic susceptibility testing and WGS.

Results
Sequence analysis revealed a new staphylococcal cassette chromosome mec (SCCmec) structure in isolate UMCG335. In this structure, plasmid pUB110 was found to be integrated into SCCmec IVc, creating a new SCCmec subtype, IVUMCG335. SCCmec IVc and a copy of plasmid pUB110 were found in other isolates, UMCG364 and UMCG341, respectively, indicating a probability that SCCmec IVUMCG335 could have evolved at the UMCG. SCCmec of UMCG337 contained a new genetic organization of the mec complex (IS431-ΔmecR1-mecA-IS431-pUB110-IS431-ψIS1272) that we have named B4. This new subclass of mec class B complex originated by IS431-mediated inversion of the DNA segment encompassing the plasmid and most of the genes of the mec complex with the exception of IS1272. As the SCCmec organization in UMCG337 differed by the inversion of an ∼10 kb sequence compared with SCCmec IVUMCG335, we have named it SCCmec subtype IVUMCG337. Isolates UMCG335 and UMCG337 carrying SCCmec IVUMCG335 and IVUMCG337, respectively, were associated with a restriction-modification system and a CRISPR-Cas system, creating a composite island of almost 70 kb.

Conclusions
Our findings highlight the importance of IS431 in the evolution of the SCCmec region. The increasing genetic diversity identified in the SCCmec elements imposes a great challenge for SCCmec typing methods and highlights possible difficulties with the SCCmec nomenclature.