bluuebunny/crossref_metadata_2025_split huggingface dataset:
STUDIES OF ENZYME POLYMORPHISMS IN THE KAMUELA POPULATION OF D. MERCATORUM. I. ESTIMATION OF THE LEVEL OF POLYMORPHISM
Authors: Clark R L , Templeton A R , Sing C F 
Published: April 2021

ABSTRACT
A Kamuela, Hawaii, population of Drosophila mercatorum was surveyed for enzyme variability. The mean heterozygosity and the proportion of polymorphic loci were estimated as 0.1255 and 0.37, respectively. Neither deviates more than one standard error from their respective means for 43 Drosophila species (Nevo 1978). Heterozygosity was distributed across enzyme categories in much the same manner as observed in other species (Gillespie and Kojima 1968; Johnson 1974), and enzymes associated with glycolysis were about as variable as other enzymes of central metabolism.——The levels of heterozygosity and polymorphism in this population do not seem to have been affected by a low-level capacity for parthenogenesis. The observed parthenogenetic reproduction is not strongly associated with particular allelic variants among viable parthenogenetic adults; however, the capacity to establish a self-sustaining parthenogenetic clone is strongly associated with the phenotype with the most frequent allele at every locus studied. We interpret these results to mean that isozyme variants do not strongly influence viability under total homozygosity (the genetic condition imposed by parthenogenesis), but they do have an impact upon the reproductive biology of parthenogenetic adults.
HIGH FREQUENCY OF GENETIC DUPLICATIONS IN THE dnaB REGION OF THE ESCHERICHIA COLI K12 CHROMOSOME
Authors: Sclafani Robert A , Wechsler James A 
Published: April 2021

ABSTRACT
The region that includes the dnaB locus on the E. coli K12 chromosome was shown to be duplicated at high frequency in cell populations. The duplications were shown to be arranged in tandem and segregated at various frequencies. Segregation was dependent on the recA recombination system, but independent of recB,C. Though most of the data was obtained with dnaB::Tn10 insertion mutants, the duplications were shown to occur in the absence of Tn10.
PERIODIC SELECTION, INFECTIOUS GENE EXCHANGE AND THE GENETIC STRUCTURE OF E. COLI POPULATIONS
Authors: Levin Bruce R 
Published: April 2021

ABSTRACT
As a consequence of sequential replacements by clones of higher fitness (periodic selection), bacterial populations would be continually purged of genetic variability, and the fate of selectively neutral alleles in very large populations of bacteria would be similar to that in demes of sexually reproducing organisms with small genetically effective population sizes. The significance of periodic selection in reducing genetic variability in these clonally reproducing species is dependent on the amount of genetic exchange between clones (recombination). In an effort to determine the relationship between the rates of periodic selection, recombination and the genetically effective sizes of bacterial populations, a model for periodic selection and infectious gene exchange has been developed and its properties analyzed. It shows that, for a given periodic selection regime, genetically effective population size increases exponentially with the rate of recombination.—With the parameters of this model in the range anticipated for natural populations of E. coli, the purging effects of periodic selection on genetic variability are significant; individual populations or lineages of this bacterial species would have very small genetically effective population sizes.—Based on this result, some other a priori considerations and a review of the results of epidemiological and genetic variability studies, it is postulated that E. coli is composed of a relatively limited number of geographically widespread and genetically nearly isolated and monomorphic lineages. The implications of these considerations of the genetic structure of E. coli populations of the interpretation of protein variation and the neutral gene hypothesis are discussed.
MALE-STERILIZING INTERACTIONS BETWEEN DUPLICATIONS AND DEFICIENCIES FOR PROXIMAL X-CHROMOSOME MATERIAL IN DROSOPHILA MELANOGASTER
Authors: Rahman Rezaur , Lindsley Dan L 
Published: April 2021

ABSTRACT
The genetic limits of sixty-four deficiencies in the vicinity of the euchromatic-heterochromatic junction of the X chromosome were mapped with respect to a number of proximal recessive lethal mutations. They were also tested for male fertility in combination with three Y chromosomes carrying different amounts of proximal X-chromosome-derived material (BSYy+, y+Ymal126 and y + Ymal +). All deficiencies that did not include the locus of bb and a few that did were male-fertile in all male-viable Df(1)/Dp(1;Y) combinations. Nineteen bb deficiencies fell into six different classes by virtue of their male-fertility phenotypes when combined with the duplicated Y chromosomes. The six categories of deficiencies are consistent with a formalism that invokes three factors or regions at the base of the X, one distal and two proximal to bb, which bind a substance critical for precocious inactivation of the X chromosome in the primary spermatocyte. Free duplications carrying these regions or factors compete for the substance in such a way that, in the presence of such duplications, proximally deficient X chromosomes are unable to command sufficient substance for proper control of X-chromosome gene activity preparatory to spermatogenesis. We conclude that there is no single factor at the base of the X that is required for the fertility of males whose genotype is otherwise normal.
MODIFICATION OF CHLOROPLAST GENE TRANSMISSION IN SOMATIC FUSION PRODUCTS AND VEGETATIVE ZYGOTES OF CHLAMYDOMONAS REINHARDI BY 5-FLUORODEOXYURIDINE
Authors: Matagne Rene F , Hermesse Marie-Paule 
Published: April 2021

ABSTRACT
Sexual crosses and somatic fusions were performed between complementing wall-less arg- mutant strains bearing chloroplast markers for resistance to antibiotics. The mode of chloroplast allele transmission was investigated in the diploid colonies developed from both vegetative zygotes and fusion products. Before mating or fusion, one or both of the parental strains were grown for 4 or 8 days on agar containing 5-fluorodeoxyuridine (FUdR, 0.1 to 1.0 mM), which selectively reduces the amount of chloroplast DNA in Chlamydomonas. When one parent was pregrown on FUdR, the frequency of vegetative zygotes transmitting chloroplast alleles of both parents (biparental or BP zygotes) decreased, the reduction being more drastic when the mt parent was treated. Transmission was mainly uniparental maternal (UPm) or paternal (UPp) depending on whether the mt- or the mt+ parent was pregrown for 8 days in the presence of 1 .OmM FUdR. Treatment of both parents led to a strong maternal transmission. In the experiments involving somatic fusion between parent 1 and parent 2(same or opposite mt), the ratio UP1/UP2, which was approximately equal to 1 in the control, decreased or increased according to whether the cells of parent 1 or 2 were pregrown on FUdR. In parallel, the frequency of BP fusion products always decreased. When both parental strains were treated with FUdR, the frequency of BP fusion products also decreased and the ratio UP,/cTP, was roughly equal to 1. The effect of FUdR can be interpreted in terms of reduction of the input frequencies of parental chloroplast genomes at the time of gametic or somatic cell fusion, the bias in favor of the maternal parent being operational only in sexual crosses.
EVIDENCE OF CHROMOSOMAL BREAKS NEAR THE MATING-TYPE LOCUS OF SACCHAROMYCES CEREVISIAE THAT ACCOMPANY MATα x MATα MATINGS
Authors: McCusker John H , Haber James E 
Published: April 2021

ABSTRACT
In order for two heterothallic MATα haploids of Saccharomyces cerevisiae to mate, one parent must apparently become, at least transiently, an a-like cell. Only about 25% of the matings result from an actual transposition of MATa sequences to replace MATα, and about 1% result from a deletion joining MAT to the normally silent HMRa allele. The majority of matings occur after an apparent chromosome break that deletes MATα and all of the known markers more distal on the right arm of chromosome III.——The chrdmosome break occurs at or very near MAT, invariably leaving the distal marker tsml hemizygous, but the closely linked proximal marker cry1 usually is heterozygous. The resulting diploid containing the broken chromosome is mitotically unstable; about 10% of the colonies contain visible sectors in which the rest of the broken chromosome is lost. The region close to the breakpoint (i.g., cryl) is unusually active in recombination. About 20% of the intact homologues remaining after chromosome loss were gene-converted for cryl. In addition, the broken end participated in reciprocal recombination events that joined the chromosome to the distal portion of the intact homologous chromosome.——The unstable diploids may also become stable and no longer give rise to mitotic segregants. We have found two distinct ways in which stabilization occurs. Most often the diploid becomes euploid by a recombination event that yields a cell homozygous for all markers distal to (and sometimes including) cryl. In one of 9 cases SO far analyzed, the stable diploid was still hemizygous for MATα and for other markers distal to MAT. This last case is similar to the healing of broken chromosomes in maize described by MCCLINTOCK(1 939,1941,1951).
INTERACTIONS BETWEEN SEX-TRANSFORMATION MUTANTS OF DROSOPHILA MELANOGASTER. I. HEMOLYMPH VITELLOGENINS AND GONAD MORPHOLOGY
Authors: Ota T , Fukunaga A , Kawabe M , Oishi K 
Published: April 2021

ABSTRACT
In Drosophila, vitellogenins (yolk protein precursors) are synthesized by the female fat body, secreted into the hemolymph and subsequently taken up by the developing oocytes. The male fat body, on the other hand, does not do this even when immature ovaries are transplanted into the body cavity and grow. Thus, the hemolymph vitellogenins serve as an easily detectable sexually dimorphic biochemical marker.——We have examined hemolymph vitellcgenins by SDS polyacrylamide gel electrophoresis in flies carrying various sex-transformation mutants (dsx, tra, tra-2 and tra-20TF) singly and in all possible combinations. Chromosomal females homozygous for tra or tra-2 have no detectable hemolymph vitellogenins, while those homozygous for tra-20TR exhibit appreciable levels of these proteins. Flies homozygous for dsz, bothX / X and X / Y, have hemolymph vitellogenins, although the amount is consistently smaller in the latter. Indeed, X / Y; dsx/dsx is the only genotype in which hemolymph vitellogenins are detected in the X/Y flies. A clear hierarchy of epistasis exists among these sex-transformation mutants when they are examined in various combinations: dsx &gt; tra, tra-2 &gt; tra-20TF. Moreover, an interaction between tra-20TF and tra was seen in these experiments: X / X; tra-20TF/tra-20TF flies show the presence of only a trace of hemolymph vitellogenins when they are made heterozygous for tra. These results, combined with observations on gonad morphology, are discussed with respect to the BAKERa nd RIDGE (1980) hypothesis of sex determination.
THE DISTRIBUTION OF RANDOMLY RECOVERED X-RAY-INDUCED SEX-LINKED GENETIC EFFECTS IN DROSOPHILA MELANOGASTER
Authors: Lefevre George 
Published: April 2021

ABSTRACT
Cytogenetic analysis of more than 1500 randomly recovered lethal Xchromosomes derived from 2QOO and 3000 r X-ray exposures of post-meiotic male germ cells has made possible a plot of the distribution in different regions of the Xchromosome of: (1) gene mutations associated with cytologically normal chromosomes, (2) mutations associated with chromosomal rearrangement breakpoints, (3) deficiencies, and (4) rearrangement breakpoints whether or not they are associated with mutations. The distribution of point mutations, vital loci and rearrangement breakpoints in different regions of the Xchromosome is not proportional to either the number of bands or the relative DNA content. Further, the density of vital loci (those capable of mutating toa lethal allele) is quite different in some regions as compared to others. For example, vital loci in the 3AB region, which has been thoroughly studied by JUDD and others, are at least as numerous as bands; whereas, the 3CD region, equally long, has only two vital loci. Other regions densely populated with vital loci include IB, 1F-2A, IOA, IIA, and 19EF; sparsely populated regions include 6EF and 10B-10E. It seems reasonable to conclude that the recovered X-rayinduced mutants available for analysis do not represent a random sample of those initially induced in the exposed male germ cells.
GENETIC DIVERSITY OF THE CYTOPLASM IN TRITICUM AND AEGILOPS. VIII. FRACTION I PROTEIN OF 39 CYTOPLASMS
Authors: Hirai Atsushi , Tsunewaki Koichiro 
Published: April 2021

ABSTRACT
The electrophoretic characteristics of the cytoplasmically controlled large subunit of the Fraction I protein of 36 alloplasmic and three euplasmic control lines are reported. These lines, representing the cytoplasms of 32Triticum and Aegilops species, had either H- or L-type large subunits in their Fraction I protein; the diploid Triticum and most Aegilops species, including Ae. bicornisand Ae. sharonensis,had the L-type subunits; whereas, all the polyploid Triticum species (emmer, timopheevi, common wheats), Ae. speltoides, Ae. aucheri,and Ae. longissimahad H-type subunits. Therefore, section Sitopsis of Aegilops exhibits interspecific heterogeneity. The H-type is believed to have originated in the Sitopsis section from an L-type subunit because of the prevalence of the latter among the diploid species.
EVIDENCE FOR AEGILOPS SHARONENSIS EIG AS THE DONOR OF THE B GENOME OF WHEAT
Authors: Kushnir U , Halloran G M 
Published: April 2021

ABSTRACT
A number of lines of evidence are advanced for the candidacy of Aegilops sharonensisEig as the donor of the B genome of wheat. The cytoplasm of Ae. shuronensis iscompatible with tetraploid wheat Triticum turgidum dicoccoides,as evidenced bythe high level of chromosome pairing and fertility of the amphiploid Ae. sharonensisx T. turgidum dicoccoides. Ae. sharonensischromosomes exhibit high levels of pairing with those of the B genome of wheat in hybrids with Ph-deficient hexaploid wheat and low levels of homoeologous pairing with T. monocmcumchromosomes.——The amphidiploid between Ae. sharonensisand T. monococcumis very similar to T. turgidum dicoccoidesin spike, spikelet and grain morphology. The karyotype of Ae. sharonensisresembles more closely that of extrapolated Bgenome karyotypes of wheat than do the karyotypes of other proposed B-genome donor species of Aegilops. Because of distinctiveness in cytological aftinity and karyotype morphology between Ae. sharonensisand Ae. longissima,a separate genome symbol Sshis proposed for the former species.
Balancing the formal and the informal in user-centred design
Authors: Harrison Michael D , Masci Paolo , Campos José Creissac 
Published: April 2021

Abstract
This paper explores the role of formal methods as part of the user-centred design of interactive systems. An iterative process is described, developing prototypes incrementally, proving user-centred requirements while at the same time evaluating the prototypes that are executable forms of the developed models using ‘traditional’ techniques for user evaluation. A formal analysis complements user evaluations. This approach enriches user-centred design that typically focuses understanding on context and producing sketch designs. These sketches are often non-functional (e.g. paper) prototypes. They provide a means of exploring candidate design possibilities using techniques such as cooperative evaluation. This paper describes a further step in the process using formal analysis techniques. The use of formal methods provides a systematic approach to checking plausibility and consistency during early design stages, while at the same time enabling the generation of executable prototypes. The technique is illustrated through an example based on a pill dispenser.
Ritual Chores: Catharine Beecher’s Domesticity
Authors: Logan Dana W 
Published: April 2021

AbstractWhat is a ritual chore? By analyzing the nineteenth-century American theorist of domesticity Catharine Beecher, this article argues that there is a form of gendered ritual that is submissive and unproductive. Unlike scholars such as Saba Mahmood and R. Marie Griffith who have argued for acknowledging the practical cultivation of virtue in conservative religious women’s piety, Beecher provides a model of gendered ritual that produced a flurry of activity rather than a self. Ritual chores, Beecher teaches us, do not result in self-mastery. The nineteenth-century middle-class Christian woman tended to her home by initiating the work of her servants; thus, her theory of domesticity was also a theory of ritual surrogacy, or the enactment of ritual at the behest of another. I argue that the dissatisfaction of the white-collar middle-manager and the nineteenth century northeastern housewife have much in common: both roles make the worker feel like their labor might in fact be pointless.
Comparative Study: Postmortem Long-Term Stability of Endogenous GHB in Cardiac Blood, Femoral Blood, Vitreous Humor, Cerebrospinal Fluid and Urine with and without Sodium Fluoride Stabilization
Authors: Küting Theresa , Madea Burkhard , Hess Cornelius , Krämer Michael 
Published: April 2021

Abstract
The interpretation of postmortem γ-hydroxybutyric acid (GHB) concentrations is challenging due to endogenous existence and postmortem GHB production in body tissues and fluids. As an additional complication, formation of GHB was also described in stored postmortem samples. We examined cardiac blood, femoral blood, vitreous humor, cerebrospinal fluid and urine of eight different corpses (male/female 5/3, aged 33–92 years, postmortem interval 1–6 days) where no intake of GHB or one of its precursors was assumed. All samples were collected during autopsy and divided into two aliquots. To one of the aliquots, sodium fluoride (NaF, 1% w/v) was added. Both aliquots were vortexed, further divided into seven aliquots and stored at −20°C. GHB concentrations were measured immediately and subsequently 1 day, 7 days, 2 weeks, 4 weeks, 3 months and 6 months, after sample collection using trimethylsilyl derivatization and gas chromatography, coupled to single quadrupole mass spectrometry. Similar progression curves of GHB concentrations were obtained for the different matrices in the individual corpses. Femoral and cardiac blood GHB concentrations were always found to be higher than in vitreous humor, cerebrospinal fluid, and urine irrespective of stabilization and storage time. None of the obtained GHB concentrations exceed the cutoff values for postmortem matrices commonly used for the identification of an exogenous GHB intake (urine, venous blood and cerebrospinal fluid: 30 mg/L, cardiac blood and vitreous humor 50 mg/L). No significant differences were found for the GHB concentrations measured immediately and 6 months after autopsy. However, we found a significant increase for the GHB concentrations 4 weeks as well as 3 months after sample collection, which was followed by a decrease nearly to initial values. There were no significant differences between samples with and without NaF addition. The data presented are useful for the interpretation of GHB concentrations in upcoming death cases, with special attention to storage conditions and different postmortem matrices.
A Material History of the DaśanāmīMaṭhaof Bodhgaya
Authors: Amar Abhishek S 
Published: April 2021

AbstractThis short essay examines the history of the Daśanāmī Giri maṭha of Bodhgaya, which has been largely ignored because of the focus on the Buddhist history of this site. Through a comparative study of nineteenth-century colonial accounts and documents, and material remains, this essay explores its claimed history and emergence as an important religio-political institution in the colonial period. In doing so, it specifically investigates network of samādhis across the villages of Gaya district and their role in establishing its position as an important zamindar.
Karyotype Description of Two Andean Species of the guarani Group of Drosophila (Díptera: Drosophilidae) and Cytological Notes
Authors: Vela Doris , Villavicencio Erika 
Published: April 2021

Abstract
The guarani group of Drosophila genus (Diptera: Drosophilidae) is formed by 24 species however the relationship of these species is not clear. In the present study are described the karyotypes of Drosophila sachapuyu Peñafiel and Rafael, 2018 and Drosophila zamorana Peñafiel and Rafael, 2018, two Andean species members of the guarani group. Mitotic chromosomes from cerebral ganglia of third stand larval were obtained by thermal shock and cell suspension techniques. The karyotype of D. sachapuyu, presents 2n = 10 (4R, 1V; X = R, Y = R) while D. zamorana exhibits karyotype 2n = 12 (5R, 1V; X = V, Y = R).
Application of Postprocessing Kinematic Methods with UAS Remote Sensing in Forest Ecosystems
Authors: Miller Zachary M , Hupy Joseph , Chandrasekaran Aishwarya , Shao Guofan , Fei Songlin 
Published: April 2021

AbstractUnmanned Aerial Systems (UAS) serve as an excellent remote-sensing platform to fulfill an aerial imagery data collection niche previously unattainable in forestry by satellites and manned aircraft. However, for UAS-derived data to be spatially representative, a precise network of ground control points (GCP) is often required, which can be tedious and limit the logistical benefits of UAS rapid deployment capabilities, especially in densely forested areas. Therefore, methods for efficient data collection without GCPs are highly desired in UAS remote sensing. Here, we demonstrate the use of postprocessing kinematic (PPK) technology to obtain subcentimeter precision in datasets of forested areas without the need for placing GCPs. We evaluated two key measures, positional variability and time efficiency, of the PPK technology by comparing them to traditional GCP methods. Results show that PPK displays consistently higher positional precision than traditional GCP approaches. Moreover, PPK surveys and processing take less time to complete than traditional GCP methods and require fewer logistical steps, especially in image acquisition. The time and resource savings with PPK as compared to GCP processing are undeniable. We conclude that PPK technology provides a practical means to produce precise aerial forest surveys.