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Homology of Nonrepeated DNA Sequences in Phylogeny of Fungal Species
Published in S. K. Dutta, DNA Systematics, 2019
Sexuality and recombination provide another method for the evolution of genes. Fundamentally, they offer a means for selecting genes, since genes (or linked groups) are more feasible units for selection than the whole genome. Genes regulating the recombination frequency have been described and studied in detail in the yeasts Neurospora, Ustilago, and Schizophyllum.56,57 In Neurospora, the controlling gene is not closely linked to the gene or region controlled and the allele giving lower recombination frequency is dominant over that giving higher. In Schizophyllum commune, Starnberg58 showed that at least two regulatory genes are responsible for the control of recombination between the A and B incompatibility factor and that the genes are separate from the controlled regions and that they segregate and recombine with respect to one another.
Understanding Aging after Darwin
Published in Shamim I. Ahmad, Aging: Exploring a Complex Phenomenon, 2017
The key ingredients of Darwin's evolutionary recipe were: variation in individual traits with some variants conferring a fitness advantage in the competition with other individuals and with respect to environmental pressures, heritability of advantageous variants making them transmissible across successive generations, and the action of natural selection. Gould (1980) noted that evolution works on several levels. At the foundational level, genes are the building blocks of species since they supply the variation upon which natural selection operates. Individual organisms are the unit of selection but individuals do not evolve. Individuals only grow, reproduce, and die. The actual unit of evolution is a group of interacting organisms defined as a species.
Coding and content analysis
Published in Louis Cohen, Lawrence Manion, Keith Morrison, Research Methods in Education, 2017
Louis Cohen, Lawrence Manion, Keith Morrison
Krippendorp (2004, pp. 99–101) distinguishes three kinds of units. Sampling units are those units which are included in, or excluded from, an analysis; they are units of selection. Recording/coding units are units contained within sampling units, i.e. smaller than sampling units, thereby avoiding the complexity that characterizes sampling units; they are units of description. Context units are units of text which set boundaries on what is to be noted, i.e. the scope of the information which informs the coding of the material (p. 103).
Posttraumatic stress disorder (PTSD) and mental health comorbidity in firefighters
Published in Journal of Workplace Behavioral Health, 2022
Nattinee Jitnarin, Sara A. Jahnke, Walker S. C. Poston, Christopher K. Haddock, Christopher M. Kaipust
The association between the presence of probable PTSD, mental health prevalence rates, and occupational health outcomes differences was evaluated using logistic regression. For continuous outcomes, statistical models were developed using SAS 9.4 PROC MIXED. Models with discrete outcomes were constructed with SAS 9.4 PROC GLIMMIX and produced adjusted least squared means. For dichotomous and ordinal variables (e.g., rating scales), the logit linking and cumulative logit linking functions within GLIMMIX were used. Statistical models of ordinal outcomes produced odds ratios which represent the effect of the predictor variables on the odds of being in a lower rather than a higher ordered category, while the models for dichotomous outcomes represented the odds of having the outcome of interest (e.g., diagnosed with mental health conditions). To account for the sampling approaches, where the fire department was the unit of selection, we also included the department as a random covariate in each statistical model. Models also were adjusted for participant’s years working in the fire service and department. Odds ratio (OR), 95% confidence interval (CI), and p-value (p < .05) were used to evaluate result for significance.
Patients in phase 1 cancer trials: psychological distress and understanding of trial information
Published in Acta Oncologica, 2022
Katrine T. Gad, Ulrik Lassen, Anne K. Duun-Henriksen, Susanne O. Dalton, Morten Mau-Sørensen, Pernille E. Bidstrup, Beverley. L. Høeg, Kristoffer S. Rohrberg, Iben Spanggard, Annika von Heymann, Christoffer Johansen
The higher level of depression in our population compared to population norms was not surprising, as the association between cancer and subsequent depression is well known from registry data of more than 600,000 adults diagnosed with cancer [25]. In our population, 11% had moderate-severe symptoms of depression (a score of ≥10 on the PHQ-9) [17]. A control population of patients not referred to the Phase 1 Unit is not available, and although the clinical stage of the cancer and the limited treatment options are arguments for comparing patients in phase 1 cancer trials to patients in palliative-care settings, patients in phase 1 cancer trials have a better performance status. Nevertheless, we found a lower prevalence of depression than that of the 16–17% reported for both patients with mixed stages/early stages of cancer and late-stage cancer [1]. Nine percent of the patients in our population had moderate to severe symptoms of anxiety (a score of ≥10 on the GAD-7), which is slightly lower than the prevalence of 10% among patients with both early and late-stage cancer [1]. This suggests better psychological health in our population than in the general cancer population. Possible explanations include the referral of patients with better psychological health to the phase 1 unit, a selection bias in our population, or a psychological benefit gained from the prospect of a positive outcome through participating in a phase 1 cancer trial.