bluuebunny/crossref_metadata_2025 huggingface dataset:
A SIMULATION STUDY OF TRUNCATION SELECTION FOR A QUANTITATIVE TRAIT OPPOSED BY NATURAL SELECTION
Authors: Minvielle Francis
Published: April 2021

A quantitative character controlled at one locus with two alleles was submitted to artificial (mass) selection and to three modes of opposing natural selection (directional selection, overdominance and underdominance) in a large random-mating population. The selection response and the limits of the selective process were studied by deterministic simulation. The lifetime of the process was generally between 20 and 100 generations and did not appear to depend on the mode of natural selection. However, depending on the values of the parameters (initial gene frequency, selection intensity, ratio of the effect of the gene to the environmental standard deviation, fitness values) the following outcomes of selection were observed: fixation of the allele favored by artificial selection, stable nontrivial equilibrium, unstable equilibrium and loss of the allele favored by artificial selection. Finally, the results of the simulation were compared to the results of selection experiments.
FUNCTIONAL EQUIVALENCE AND CO-DOMINANCE OF HOMOTHALLIC GENES HMα/hmα AND HM
a/hm
a IN SACCHAROMYCES YEASTS
Authors: Harashima Satoshi , Oshima Yasuji
Published: April 2021

The specificity of mating type in Saccharomyces yeasts is controlled by a pair of alleles, a and α, on chromosome III. They are mutually interconverted by the function of three kinds of homothallic genes, each consisting of a single pair of alleles, HO/ho, HMα/hmα and HMa/hma. For the a to α conversion, HO HMα HMa, HO hmα HMa and HO hmα hma genotypes are effective; whereas, the α to a conversion occurs in HO HMα HMa, HO HMα hma and HO hmα hma cells. To explain these observations, Naumov and Tolstorukov (1973) and Harashima, Nogi and Oshima (1974) suggested that hma and HMα are functionally equivalent and effective for the α to a conversion in combination with HO; whereas, hmα and HMa are functionally equivalent and effective for the a to α conversion with the function of HO. To test this idea and to compare it with two other possible mechanisms, some of the tetrad segregants from four kinds of a/a/α/α tetraploids homozygous for the HO allele and for one of the HMα/hmα and HMa/hma loci, while heterozygous for the other one with +/+/-/- configuration, were investigated with respect to their thallism by self-sporulation. Results indicated the functional equivalence of both the HMα and hma alleles and the hmα and HMα alleles in mating-type conversion, and the co-dominance of the alleles of each locus. From these findings and other data, we agree with the revision of the nomenclature of the HMα/hmα and HMa/hma genes to HMRa/HMRα and HMLα/HMLa, respectively.
TECHNIQUES AND MARKER GENES FOR USE IN MACROCYST GENETICS WITH POLYSPHONDYLIUM PALLIDUM
Authors: Francis David
Published: April 2021

Previous work has shown that genetic exchange occurs in the macrocyst of Polysphondylium pallidum, as in species of Dictyostelium. These studies are extended here. Mutants resistant to six different poisons have been isolated for use as genetic markers. A replica-plating technique has been engineered whereby 14 progeny clones growing on a master plate may be simultaneously transferred to test plates containing individual poisons. Germination percent of macrocysts has been greatly increased by the presence of a growing fungus during the resting stage. These means have been used to analyze crosses showing that: (1) Vegetative amebae are haploid, at least at the three marker loci tested. (2) Amebae emerging from a single macrocyst are identical about 90% of the time. (3) Any single combination of parental markers may emerge from a given macrocyst, and all combinations appear in approximately equal frequencies. These findings suggest that normally one of four nuclei produced by meiosis survives in every macrocyst and that all markers examined are unlinked. (4) About 10% of the macrocysts germinate to give two or more classes of progeny. These may result from the presence of a second zygote in the macrocyst or from the survival of two nuclei after meiosis. (5) If genetic exchange occurs during spore formation or microcyst formation, its frequency is low (<0.01%).
unc-93(e1500): A BEHAVIORAL MUTANT OF CAENORHABDITIS ELEGANS THAT DEFINES A GENE WITH A WILD-TYPE NULL PHENOTYPE
Authors: Greenwald Iva S , Horvitz H Robert
Published: April 2021

The uncoordinated, egg-laying-defective mutation, unc-93(e1500) III, of the nematode Caenorhabditis elegans spontaneously reverts to a wild-type phenotype. We describe 102 spontaneous and mutagen-induced revertants that define three loci, two extragenic (sup-9 II and sup-10 X) and one intragenic. Genetic analysis suggests that e1500 is a rare visible allele that generates a toxic product and that intragenic reversion, resulting from the generation of null alleles of the unc-93 gene, eliminates the toxic product. We propose that the genetic properties of the unc-93 locus, including the spontaneous reversion of the e1500 mutation, indicate that unc-93 may be a member of a multigene family. The extragenic suppressors also appear to arise as the result of elimination of gene activity; these genes may encode regulatory functions or products that interact with the unc-93 gene product. Genes such as unc-93, sup-9 and sup-10 may be useful for genetic manipulations, including the generation of deficiencies and mutagen testing.
MEIOTIC BEHAVIOR OF COMPOUND AUTOSOMES IN FEMALES OF DROSOPHILA MELANOGASTER: INTERCHROMOSOMAL EFFECTS AND THE SOURCE OF SPONTANEOUS NONSEGREGATION
Authors: Harger Hideh , Holm David G
Published: April 2021

In females of Drosophila melanogaster, compound autosomes enter the repulsion phase of meiosis uncommitted to a particular segregation pattern because their centromeres are not restricted to a bivalent pairing complex as a consequence of crossing over. Their distribution at anaphase, therefore, is determined by some meiotic property other than exchange pairing, a property that for many years has been associated with the concept of nonhomologous pairing. In the absence of heterologous rearrangements or a free Y chromosome, C(3L) and C(3R) are usually recovered in separate gametes, that is as products of meiotic segregation. Nevertheless, there is a regular, albeit infrequent, recovery of reciprocal meiotic products (the nonsegregational products) that are disomic and nullosomic for compound thirds. The frequency of these exceptions, which is normally between 0.5 and 5.0%, differs for the various strains examined, but remains constant for any given strain. Since previous studies have not uncovered a cause for this base level of nonsegregation, it has been referred to as the spontaneous frequency. In this study, crosses between males and females whose X chromosomes, as well as compound autosomes, are differentially marked reveal a highly significant positive correlation between the frequency of compound-autosome nonsegregation and the frequency of X-chromosome nondisjunction. However, an inverse correlation is found when the frequency of nondisjunction is related to the frequency of crossing over in the proximal region of the X chromosome. These findings have been examined with reference to the distributive pairing and the chromocentral models and interpreted as demonstrating (1) that nonsegregational meiotic events arise primarily as a result of nonhomologous interactions, (2) that forces responsible for the segregation of nonhomologous chromosomes are properties of the chromocentral region, and (3) that these forces come into expression after the exchange processes are complete.
RECOMBINATION AND CHROMOSOME SEGREGATION DURING THE SINGLE DIVISION MEIOSIS IN SPO12–1 AND SPO13–1 DIPLOIDS
Authors: Klapholz Sue , Esposito Rochelle Easton
Published: April 2021

This paper reports a study of chromosome segregation and recombination during sporulation of spo12—1 and spo13–1 diploid strains of S. cerevisiae. These strains undergo a single division to form asci containing two diploid or near-diploid spores. The segregation of centromere-linked markers in the two-spored (dyad) products indicates that the division is generally equational. However, in a small percentage of the spo12–1 and spo13–1 cells, it appears that a meiosis I-like division occurs. Aberrant segregation of the MAT locus on chromosome III, yielding a monosomic and a trisomic spore pair, occurs in 12% of all dyads. The segregation patterns of markers at various distances from their centromeres and several pairs of markers on the same chromosome indicate that recombination takes place in both strains at nearly standard meiotic levels.
ACTIVITY VARIANTS OF ACID PHOSPHATASE-3 AMONG CHROMOSOME 3 INVERSIONS OF DROSOPHILA PSEUDOOBSCURA
Authors: Norman R A , Prakash Satya
Published: April 2021

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

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

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

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

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

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

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

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

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

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

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

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

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

Online 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

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

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.
Defining and Reporting on Critical Values in Genetics: A Laboratory Survey
Authors: Goh Elaine S , Stavropoulos Dimitrios J , Adeli Khosrow
Published: April 2021

Background

Although an obvious critical value in metabolic genetics would be ammonia, it is more challenging to define critical values in molecular genetics and cytogenetics. The objective of this study was to survey genetic laboratories in Ontario, Canada, to determine whether different centers considered similar results as critical and thus potentially deserving of a different reporting process.

Methods

An online 11-question survey was emailed to Ontario laboratory directors, and the results were analyzed.

Results

The response rate was 82% (9/11). Cytogenetics and molecular genetics services were each provided by 7 of the 9 centers, with 3 centers providing biochemical/metabolic genetics services and 1 providing maternal marker serum screening services. The case type (e.g., prenatal, newborn, or expedited by the ordering physician) was one factor. Quantitative fluorescence PCR for autosomal aneuploidy, pathogenic variants in both prenatal and postnatal settings, and oncological results were considered critical cytogenetics results. Pathogenic prenatal cases, indeterminate results, and unexpected results were considered more critical for molecular genetics. Critical results were more likely to prompt a telephone call or email to the ordering physician.

Conclusion

Ontario genetics laboratories tended to have similar reporting processes for critical results. Both the types of cases and the pathogenicity of the result define what values are considered critical.
Global value chains, private governance and multiple end-markets: insights from Kenyan leather
Authors: Pasquali Giovanni , Alford Matthew
Published: April 2021

This article analyses how the private governance of global value chains (GVCs) varies across multiple end-markets. This is explored through a two-stage mixed-methods analysis of Kenya’s participation in leather value chains serving Europe, China, India and the COMESA region. We first draw on transaction-level customs data to analyse private governance in terms of the stability of buyer–supplier interactions and presence of intermediaries. We then interrogate these results through supplier interviews. Our article highlights the combined role of product specifications and trust in shaping private governance, and heterogeneity of GVCs across the global North and South, as well as within the South. It further questions commonly held assumptions that lower quality products (generally characterising Southern end-markets) are necessarily governed by market-based coordination mechanisms. We therefore challenge links established in the GVC literature between product standards and private governance.
Emerging Adults’ Adherence to Preventative Health Guidelines in Response to COVID-19
Authors: Feldman Estée C H , Balistreri Kathryn A , Lampert Sara , Durkin Lindsay K , Bugno Lindsey T , Davies W Hobart , Greenley Rachel Neff
Published: April 2021

Objective

To examine rates of emerging adults’ (EA) adherence to preventative health behavior recommendations during early months of the COVID-19 pandemic and to investigate demographic (i.e., gender, years of education, socioeconomic status, school enrollment status, and living situation) and exposure and impact-related correlates of adherence.

Methods

Participants were 273 [M (SD) age = 22 (2.1) years, 55% female, 32% from minoritized groups] EA completed an online survey of adherence to 11 preventative health behaviors recommended by the Centers for Disease Control (CDC) during summer 2020. Participants rated adherence via a visual analog scale. Participants also reported demographic information and completed the COVID-19 Exposure and Family Impact Adolescent and Young Adult Version (CEFIS-AYA).

Results

Median levels of adherence to preventative recommendations ranged from 66% to 100%. Highest adherence levels (Mdn > 90%) were reported for quarantining if exposed to COVID-19; covering mouth when sneezing; avoiding the elderly/those at high risk; and avoiding large gatherings. Median adherence was <80% for mask wearing; maintaining a 6-foot distance; avoiding in-person visits with romantic partners or friends; and disinfecting surfaces. Female gender was the only variable significantly associated with overall adherence, and it explained 4% of the variance.

Conclusions

Following guidelines related to social distancing practices may be particularly challenging for EA, possibly because of unique developmental needs of this group, and males may be at greater risk for non-adherence to CDC recommendations. Therefore, public health messaging and adherence intervention development should be designed with males and social distancing practices in mind.
Receptor-like cytoplasmic kinase MAZZA mediates developmental processes with CLAVATA1 family receptors in Arabidopsis
Authors: Blümke Patrick , Schlegel Jenia , Gonzalez-Ferrer Carmen , Becher Sabine , Pinto Karine Gustavo , Monaghan Jacqueline , Simon Rüdiger
Published: April 2021

The receptor-like kinases (RLKs) CLAVATA1 (CLV1) and BARELY ANY MERISTEMs (BAM1–BAM3) form the CLV1 family (CLV1f), which perceives peptides of the CLV3/EMBRYO SURROUNDING REGION (ESR)-related (CLE) family within various signaling pathways of Arabidopsis thaliana. CLE peptide signaling, which is required for meristem size control, vascular development, and pathogen responses, involves the formation of receptor complexes at the plasma membrane. These complexes comprise RLKs and co-receptors in varying compositions depending on the signaling context, and regulate expression of target genes, such as WUSCHEL (WUS). How the CLE signal is transmitted intracellularly after perception at the plasma membrane is not known in detail. Here, we found that the membrane-associated receptor-like cytoplasmic kinase (RLCK) MAZZA (MAZ) and additional members of the Pti1-like protein family interact in vivo with CLV1f receptors. MAZ, which is widely expressed throughout the plant, localizes to the plasma membrane via post-translational palmitoylation, potentially enabling stimulus-triggered protein re-localization. We identified a role for a CLV1–MAZ signaling module during stomatal and root development, and redundancy could potentially mask other phenotypes of maz mutants. We propose that MAZ, and related RLCKs, mediate CLV1f signaling in a variety of developmental contexts, paving the way towards understanding the intracellular processes after CLE peptide perception.
The demographic determinants of inter-provincial migration declines in Canada: A decomposition analysis
Authors: White Nathaniel , Haan Michael
Published: April 2021

This article studies the link between observed demographic changes and Canadian inter-provincial migration declines. Alongside recent changes in age composition, educational attainment, marital trends, and immigration, Canadian internal migration has widely been in decline. In this context, our project investigates the demographic determinants of Canadian provincial migration and the correlation between Canada’s socio-demographic shifts and the decline of inter-provincial migration. To do so, our analysis consists of two identical multivariate logistic regressions and an econometric decomposition using the data of the 1991 and 2016 Canadian Census Public Use Microdata Files. The dependent variable is inter-provincial migration, and the focal independent variables are age, educational attainment, marital status, immigrant status, and province of residence five years ago. By investigating how these determinants are associated with migration, we develop a greater understanding of how demographics predict inter-provincial migration in Canada, and how these demographics have changed and affected the overall decline in inter-provincial migration. In a broad sense, we examine the continuity of contemporary demographic trends in their relation to Canadian macro-economic human capital distribution. Through our investigation, we conclude that while compositional changes have some impact, it is a shift in the effects of these changes that largely explains the decline in Canadian inter-provincial migration.
Expanding Opportunities: An Evaluation of Uniformed Services University’s Premedical Program for Enlisted Service Members
Authors: Green Althea , Konopasky Abigail , Dong Ting , Saguil Aaron , Torre Dario , Durning Steven J
Published: April 2021

Introduction

Medical school leaders are seeking strategies to increase the diversity of their student populations. Post-baccalaureate premedical (PBPM) programs are one such pipeline that has supported diversity in medicine. The purpose of this study was to evaluate the Uniformed Services University’s (USU’s) PBPM program (the Enlisted to Medical Degree Preparatory Program, EMDP2) to determine how well it prepares its learners for the School of Medicine (SOM).

Materials and Methods

The National Board of Medical Examiners Clinical Science Subject Examination scores of EMDP2 learners from the SOM classes of 2020–2023 were compared to those of four similarly sized cohorts of their peers that varied by age and prior military service.

Results

We found that the performance of program graduates was comparable to their peers who followed more traditional and other alternative preparatory paths.

Conclusions

The EMDP2 appears to prepare medical students on a par with their non-EMDP2 peers. The EMDP2 contributes to USU’s commitment to train physicians who represent the nation and its citizens by making medical education available to enlisted service members, a population that closely mirrors the diversity of the nation.
Pattern of Cumulative Treatment Hours on Pain Impact and PROMIS Outcomes
Authors: Li Hongjin , Flynn Diane M , Highland Krista B , Burke Larisa A , Mcquinn Honor M , Steffen Alana D , Doorenbos Ardith Z
Published: April 2021

Introduction

Participation in interdisciplinary treatments is associated with improvement in pain intensity, physical function, and additional pain-related outcome domains. However, the effect of cumulative treatment hours on outcomes remains unknown among military patients. The present analysis examined the relationship between cumulative interdisciplinary treatment hours and pain management outcomes at a single interdisciplinary pain management center (IPMC).

Materials and Methods

This is a retrospective observational study of data previously collected as standard of care at the Madigan Army Medical Center, approved by the Institutional Review Board. We included patients who received treatment at the IPMC and completed at least two self-report assessment batteries: one at baseline and at least one between 90 and 180 days after baseline (n = 882). The primary outcome was pain impact. Secondary outcomes included fatigue, depression, anxiety, and sleep-related impairment.

Results

Generalized additive models indicated that cumulative treatment hours were significantly associated with improvement in pain impact, fatigue, and depression. Patients who had higher baseline pain impact, who had mild or no depressive symptoms, and who were >40 years of age had greater improvements in pain impact following treatment, relative to those with lower pain impact, moderate-to-severe depressive symptoms, and were 40 years of age or younger, respectively. Additional research is needed to elucidate the effect of different therapies and additional patient factors in understanding the “therapeutic dose” of interdisciplinary pain management.

Conclusions

A higher number of cumulative treatment hours was associated with improvement of pain impact, fatigue, and depression among military personnel receiving interdisciplinary pain treatment. At least 30 hours of sustained interdisciplinary treatment appears to be the threshold for improvement in pain impact and related outcomes.
Injuries and Referral Patterns During Basic Combat Training: An Examination of Data From the Certified Athletic Trainer-Forward Program
Authors: Hirschhorn Rebecca M , Yeargin Susan W , Mensch James M , Dompier Thomas P
Published: April 2021

Introduction

Injuries sustained during basic combat training (BCT) result in large economic costs to the U.S. Army. The inclusion of athletic trainers (ATs) in other military branches has reduced Troop Medical Clinic (TMC) referrals. However, the inclusion of ATs during BCT has yet to be studied. The purpose of this study was to describe the frequency and nature of sick call visits during BCT and determine how the presence of an AT affects referrals to the TMC.

Materials and Methods

A prospective cohort study was conducted at the Fort Jackson Army Training Center for one calendar year. Soldiers in BCT, aged 18–42, who reported to sick call were included. Independent variables collected included: Soldier demographics (sex and age), visit reason, and provider impression. Training battalions were placed in three conditions: control (CON), full-time medic (FTM), and part-time athletic trainer (PAT). The dependent variable was disposition (referred or returned to duty [RTD]). Frequencies and proportions were calculated. Logistic regression compared conditions while considering the other independent variables. Return on investment was calculated.

Results

Fourteen thousand three hundred and four visits were documented. Most soldiers were female (n = 7,650; 53.5%) and under 20 years old (n = 5,328; 37.2%). Visits were most commonly due to physical injury (n = 7,926; 55.4%), injuries affecting the knee (n = 2,264; 15.8%) and chronic/overuse conditions (n = 2,031; 14.2%). By condition, the FTM and PAT conditions resulted in 1.303 (95%CI: 1.187, 1.430; P < .001) and 1.219 (95%CI: 1.103, 1.348; P < .001), or 30.3% and 21.9% higher, odds of being RTD compared to the CON condition, respectively. Return on investment was $23,363,596 overall and $2,423,306 for musculoskeletal-related cases.

Conclusions

Injuries were common in BCT, particularly in females. Soldiers in both the PAT and FTM conditions were more likely to be RTD compared to those in the CON condition. Athletic trainers (ATs) are effective at reducing potentially unnecessary referrals, demonstrating their value as healthcare providers in the BCT environment. Understanding variables associated with recruit disposition may aid medics and ATs in the development of triage protocols and further reduction of potentially unnecessary soldier referrals. The Certified Athletic Trainer-Forward Program resulted in significant return on investment, further supporting the inclusion of ATs in BCT.
Preventing Surgical and Postpartum Hemorrhage in an Active Duty Patient With an Undiagnosed Coagulopathy at a Military Treatment Facility
Authors: Kopelman Zachary A , Villazana-Kretzer Diana , Yamasaki Meghan
Published: April 2021

Factor VII (FVII) deficiency is a hereditary bleeding disorder that significantly increases the risk of hemorrhage during the intrapartum and postpartum periods as well as during surgery. Management often requires careful pre- and post-operative planning, a multi-disciplinary approach, and management at a tertiary center. Most cases in the literature utilized recombinant FVII for treatment. We present a case of a young active duty female who had an undiagnosed FVII deficiency that became apparent during her expedited delivery for fetal distress. Our patient was admitted for delivery while undergoing a work up for an abnormal coagulation panel. Given high suspicion for FVII deficiency, anticipated hemorrhage, and need for cesarean delivery, she was treated with blood products containing FVII. Two days after delivery her diagnosis was confirmed. Available literature discusses the management of known FVII deficiency in pregnancy; however, to the best of our knowledge, there are no cases of an unknown bleeding diathesis incidentally identified just before delivery and later diagnosed as FVII deficiency. This case highlights the appropriate management of an unknown coagulopathy, the significant challenges associated, and the incorporation of a multi-disciplinary team critical to reducing significant maternal morbidity.