Towards a pedagogy for noticing: Piloting a novel intervention for health professions students

Teaching students to 'notice' what is happening around them, to be more attuned to what is going on within themselves, and nurturing self-inquiry into one's practice is desirable yet difficult to achieve. We sought to teach the metacognitive skill of 'noticing' to pre-registration health professions students in the context of interprofessional collaborative practice (IPCP). A three-part curriculum was designed: an e-module focused on 'noticing' in IPCP; a team-based workplace learning observation and interprofessional debrief; and a written reflective assignment. We found that students concentrated on the disciplinary content of IPCP in the assignments, which 'overshadowed' the metacognitive content. We learned that: we had underestimated the challenges of retrofitting new content into existing curricula; that we had not paid enough attention to students' perceptions about what they want to learn; and working with a large and diverse group of educators requires adequate preparation. The next iteration of this program will improve the constructive alignment between learning outcomes and assessments and provide better support for educators. In the future we will temper decisions to act quickly to implement curricular innovations. More broadly, we suggest that educational design that seeks to take account of qualitatively different but intersecting knowledge domains, such as IPCP and 'noticing', is worthy of further study.

The work performed through interprofessional meeting discourse: an observational study

The effectiveness of work performed through interprofessional practice is contingent on the nature and extent of communication between professionals. To date, there is little research exploring how the patterns of communication may impact interprofessional work. This study focused on communication during interprofessional meetings to better understand the interprofessional work performed through these encounters. Specifically, it examined how interactional discourse, that is, the patterns of language, influenced work performed during interprofessional meetings. A series of four interprofessional meetings in a rehabilitation unit were observed. Twenty-one participants were observed, including medical, nursing, allied health clinicians, and health professions students. Follow-up stimulated-recall interviews were conducted with five meeting participants. The data collection consisted of video and audio recordings and detailed field notes. Data were analyzed using a combination of genre analysis, a form of discourse analysis, and activity system analysis, drawing on Cultural Historical Activity Theory. This facilitated an in-depth examination of the structure of discourse and its influence on meeting outcomes. The meeting structure was defined and predictable. Two distinct forms of discourse were identified and labeled scripted and unscripted. Scripted discourse was prompted by standardized documents and facilitated the completion of organizational work. In contrast, unscripted discourse was spontaneous dialogue used to co-construct knowledge and contributed to collaboration. There was constant shifting between scripted and unscripted discourse throughout meetings which was orchestrated by experienced clinicians. Rather than fragmenting the discussion, this shifting enabled shared decision making. This research provides further insights into the interprofessional work performed during interprofessional meetings. The scripted discourse was highly influenced by artifacts (communication tools) in meetings, and these were used to ensure organizational imperatives were met. Unscripted discourse facilitated not only new insights and decisions but also social cohesion that may influence work within and outside the meeting.

Meaning making about performance: A comparison of two specialty feedback cultures

INTRODUCTION

Specialty trainees often struggle to understand how well they are performing, and feedback is commonly seen as a solution to this problem. However, medical education tends to approach feedback as acontextual rather than located in a specialty-specific cultural world. This study therefore compares how specialty trainees in surgery and intensive care medicine (ICM) make meaning about the quality of their performance and the role of feedback conversations in this process.

METHODS

We conducted a qualitative interview study in the constructivist grounded theory tradition. We interviewed 17 trainees from across Australia in 2020, eight from ICM and nine from surgery, and iterated between data collection and analytic discussions. We employed open, focused, axial and theoretical coding.

FINDINGS

There were significant divergences between specialties. Surgical trainees had more opportunity to work directly with supervisors, and there was a strong link between patient outcome and quality of care, with a focus on performance information about operative skills. ICM was a highly uncertain practice environment, where patient outcome could not be relied upon as a source of performance information; valued performance information was diffuse and included tacit emotional support. These different 'specialty feedback cultures' strongly influenced how trainees orchestrated opportunities for feedback, made meaning of their performance in their day-to-day patient care tasks and 'patched together' experiences and inputs into an evolving sense of overall progress.

DISCUSSION

We identified two types of meaning-making about performance: first, trainees' understanding of an immediate performance in a patient-care task and, second, a 'patched together' sense of overall progress from incomplete performance information. This study suggests approaches to feedback should attend to both, but also take account of the cultural worlds of specialty practice, with their attendant complexities. In particular, feedback conversations could better acknowledge the variable quality of performance information and specialty specific levels of uncertainty.

In-verse reflection: structured creative writing exercises to promote reflective learning in medical students

Medical educators recognize the value of reflection for medical students and the role creative writing can play in fostering this. However, direct creative writing tasks can be challenging for many students, particularly those with limited experience in the arts and humanities. An alternative strategy is to utilize an indirect approach, engaging students with structured tasks that obliquely encourage reflection. This paper reports one such approach. We refer to this approach as in-verse reflection, playing on both the structure of the writing and its novel approach to reflection. Students were invited to write, in verse-like structures, about their personal and clinical experiences as medical students. Thematic analysis of their creative outputs and reactions identified four principal themes: the challenges of life as a medical student, the emotional demands of the medical course, a sense of connectedness and solidarity with fellow students, and a sense of marginality within the hospital system. Students generally found the tasks highly engaging and conducive to reflection, producing texts representing significant insights into their experiences as medical students. The reported method offers a relatively simple, structured, and guided approach to reflective writing, adding to the repertoire of methods available to educators in the medical humanities.

Dynamic and distributed exchanges: an interview study of interprofessional communication in rehabilitation

PURPOSE

Interprofessional communication (IPC) in rehabilitation is important for patient care yet it has been shown to be variable and challenging. Existing research does not address the complexity of IPC in this setting. Understanding the influence of contextual factors on IPC may guide improvements to increase the effectiveness of communication within interprofessional teams.

METHODS

From July 2020 to February 2021 semi-structured interviews were conducted with 24 healthcare professionals across Australia and New Zealand. Cultural Historical Activity Theory provided a guiding theoretical and analytical framework for this qualitative study.

RESULTS

Participants described engaging in IPC through evolving interactions, piecing together information that underpinned patient care. Meetings occurred frequently, however communication extended well beyond formalised interactions, often requiring individuals to balance clinical workload with communication tasks. IPC reportedly relied on communication tools, however navigating information from multiple sources was demanding.

CONCLUSIONS

Our results indicate that IPC contributes significantly to the workload of healthcare professionals in rehabilitation. IPC was integral in the provision of cohesive patient care, however it proved time consuming, effortful and at times frustrating and potentially erroneous. Our findings promote the need for rigorous examination of communication practices to ensure they are meeting the needs of an increasingly interprofessional workforce. IMPLICATIONS FOR REHABILITATIONHealthcare professionals should recognise that time spent communicating within their team is a legitimate and important part of patient care.Rehabilitation teams should consider how they allocate resources for communication tasks.Teams should reconsider how they can use communication more effectively to save time by reducing repetition and errors.

Communication in interprofessional rehabilitation teams: a scoping review

PURPOSE

Effective communication in interprofessional rehabilitation teams is essential for optimal patient care. Despite the established importance, it remains unclear how interprofessional communication (IPC) within teams contributes to rehabilitation service delivery. The aim of this scoping review was to investigate how IPC has been described in rehabilitation literature.

METHODS

Databases (Medline, CINAHL, ERIC, Embase, PsychInfo, and Academic Search Complete) were searched for studies including rehabilitation interprofessional communication. Inclusion and exclusion criteria were identified and applied, data were charted, and thematic analysis conducted.

RESULTS

Twenty-nine papers were identified, and analysis revealed interrelated themes: communication processes, and inputs and effects. Formal communication processes were most prevalent, portraying variability in professional participation and a lack of patient involvement in dialogue and decision making. Inputs and effects were described at an organisational, team and individual level, highlighting the importance of communication throughout the healthcare hierarchy.

CONCLUSIONS

IPC in rehabilitation is central to effective team function and patient care. To further our understanding, empirical studies examining everyday informal IPC, as well as formal ritualised encounters are needed. Additionally, conceptualisations of IPC would benefit from including the patients' perspective and by using theoretical framing to attend to places, spaces, and artefacts identified in this review.

Supervision training in healthcare: a realist synthesis

Supervision matters: it serves educational, supportive and management functions. Despite a plethora of evidence on the effectiveness of supervision, scant evidence for the impact of supervision training exists. While three previous literature reviews have begun to examine the effectiveness of supervision training, they fail to explore the extent to which supervision training works, for whom, and why. We adopted a realist approach to answer the question: to what extent do supervision training interventions work (or not), for whom and in what circumstances, and why? We conducted a team-based realist synthesis of the supervision training literature focusing on Pawson's five stages: (1) clarifying the scope; (2) determining the search strategy; (3) study selection; (4) data extraction; and (5) data synthesis. We extracted contexts (C), mechanisms (M) and outcomes (O) and CMO configurations from 29 outputs including short (n = 19) and extended-duration (n = 10) supervision training interventions. Irrespective of duration, interventions including mixed pedagogies involving active and/or experiential learning, social learning and protected time served as mechanisms triggering multiple positive supervisor outcomes. Short-duration interventions also led to positive outcomes through mechanisms such as supervisor characteristics, whereas facilitator characteristics was a key mechanism triggering positive and negative outcomes for extended-duration interventions. Disciplinary and organisational contexts were not especially influential. While our realist synthesis builds on previous non-realist literature reviews, our findings extend previous work considerably. Our realist synthesis presents a broader array of outcomes and mechanisms than have been previously identified, and provides novel insights into the causal pathways in which short and extended-duration supervision training interventions produce their effects. Future realist evaluation should explore further any differences between short and extended-duration interventions. Educators are encouraged to prioritize mixed pedagogies, social learning and protected time to maximize the positive supervisor outcomes from training.

Supervision training interventions in the health and human services: realist synthesis protocol

INTRODUCTION

Supervision training aims to develop workplace supervisory competencies. Despite extensive supervision literature, including literature reviews, the processes through which supervision training interventions produce their effects, for whom and under what circumstances is not clearly delineated. The purpose of this study is to explain the effect of contextual factors on the underpinning mechanisms of supervision training outcomes.

METHODS AND ANALYSIS

We propose to examine supervision training interventions across the health and human services workforce using realist methods. Pawson's five stages for undertaking a realist synthesis will be followed: (1) clarifying the scope of the review; (2) determining the search strategy; (3) study selection; (4) extracting data and (5) synthesising the evidence and drawing conclusions. Extracted data will include study characteristics, characteristics of participant cohort, intervention type, contextual factors, underlying mechanisms and supervision training outcomes. Patterns in context-mechanism-outcome configurations will be identified. Initial programme theories will be developed based on a comprehensive search of the literature, which will include key terms relating to supervision and training. The search strategy will involve: (1) electronic database searching using Medline, Cumulative Index to Nursing and Allied Health Literature, Social Services Abstracts, Educational Resources Information Center, PsycINFO and Australian Public Affairs Information Service and (2) hand and citation searching. We will also contact authors where necessary and discuss identified literature among the project team with extensive expertise in supervision training.

ETHICS AND DISSEMINATION

The realist synthesis will propose an evidence-informed theory of supervision training interventions (ie, what interventions work for whom and why). The findings will be disseminated in peer-reviewed journals and presentations and through discussions with relevant organisations and stakeholders. The research will be used by educators to develop evidenced-based supervision training interventions. It will also help workplace supervisors to better understand what types of supervision training might work most optimally for them and their colleagues. Other researchers could use the synthesis findings to guide future supervision research.

PROSPERO REGISTRATION NUMBER

CRD42018094186.

Healthcare professionals' perceptions of learning communication in the healthcare workplace: an Australian interview study

OBJECTIVES

The literature focuses on teaching communication skills in the 'classroom', with less focus on how such skills are informally learnt in the healthcare workplace. We grouped healthcare work based on the cure:care continuum to explore communication approaches based on work activities. This study asks: 1) How do healthcare professionals believe they learn communication in the workplace? 2) What are the differences (if any) across the 'type of work' as represented by the cure:care continuum?

DESIGN

This qualitative study used semi-structured individual interviews.

SETTING

Community care and acute hospitals in Australia (Victoria and New South Wales).

PARTICIPANTS

Twenty qualified healthcare professionals (medicine n=4, nursing n=3, allied health n=13) from various clinical specialties (eg, acute, rehabilitation, surgery, palliative care) participated.

METHODS

Data were analysed using framework analysis, which involved the development of a thematic coding framework. Findings were mapped to participants' descriptions of work using the cure:care continuum.

RESULTS

Three themes were identified that varied across the cure:care continuum: professional discourse-tying communication approaches to work activities; personal identities-the influence of personal identities on healthcare communication and role modelling-the influence of others in the socially bound context of healthcare work.

CONCLUSIONS

This study highlights the influence of professional, personal and social factors on the learning of healthcare communication in the workplace. Our study illuminates differences in communication practice related to work activities, as conceptualised by the cure:care continuum. The results call for further examination of the 'nature' of work activities and the concomitant influence on developing healthcare communication.

'I will never ever go back': patients' written narratives of health care communication

CONTEXT

Although communication with patients is essential to health care, education designed to develop patient-centred communication often ignores patients' voices. Patient stories may offer a means to explore patient experiences to inform patient-centred communication skills education design.

OBJECTIVES

Our research questions were: (i) What are the features of patients' health care communication narratives? (ii) What differences exist between patient narratives evaluated as positive and those evaluated as negative? (iii) How do patients narrate emotion in their narratives?

METHODS

This interpretivist research was underpinned by social constructionism. We employed a narrative approach to design an online questionnaire that was advertised to patients in the community. Analysis of the stories that were generated involved analysis of what was written (i.e. framework analysis) and of how it was written (i.e. attending to linguistic features).

RESULTS

Participants shared 180 written narratives about previous health care professional (HCP) communication interactions. Narratives commonly included those of female patients seeking help for musculoskeletal or psychological concerns, which most frequently had occurred within the previous 6 months with male general practitioners in community settings. Framework analysis revealed four key themes: (i) patient actions during consultations; (ii) patient actions afterwards; (iii) lasting legacy, and (iv) interpersonal factors. Patients in narratives evaluated as positive actively engaged during and after interactions, had ongoing positive relationships with HCPs and felt valued in these relationships. Patients in narratives evaluated as negative were either passive or active during the interaction, but mostly failed to return to the HCP and felt devalued in their interaction. Further analysis of the linguistic features of select narratives revealed rich constructions of positive and negative emotions emphasising the lasting legacies of these interactions.

CONCLUSIONS

Analysis of patient narratives provides a detailed way of exploring patients' experiences, emotions and behaviours during and after consultations. Educational implications include emphasising the importance of valuing the patient, and of seeking and acting on patient feedback to calibrate HCPs' patient-centred communication practices.

Learning outcomes for communication skills across the health professions: a systematic literature review and qualitative synthesis

OBJECTIVE

The aim of this study was to identify and analyse communication skills learning outcomes via a systematic review and present results in a synthesised list. Summarised results inform educators and researchers in communication skills teaching and learning across health professions.

DESIGN

Systematic review and qualitative synthesis.

METHODS

A systematic search of five databases (MEDLINE, PsycINFO, ERIC, CINAHL plus and Scopus), from first records until August 2016, identified published learning outcomes for communication skills in health professions education. Extracted data were analysed through an iterative process of qualitative synthesis. This process was guided by principles of person centredness and an a priori decision guide.

RESULTS

168 papers met the eligibility criteria; 1669 individual learning outcomes were extracted and refined using qualitative synthesis. A final refined set of 205 learning outcomes were constructed and are presented in 4 domains that include: (1) knowledge (eg, describe the importance of communication in healthcare), (2) content skills (eg, explore a healthcare seeker's motivation for seeking healthcare),( 3) process skills (eg, respond promptly to a communication partner's questions) and (4) perceptual skills (eg, reflect on own ways of expressing emotion).

CONCLUSIONS

This study provides a list of 205 communication skills learning outcomes that provide a foundation for further research and educational design in communication education across the health professions. Areas for future investigation include greater patient involvement in communication skills education design and further identification of learning outcomes that target knowledge and perceptual skills. This work may also prompt educators to be cognisant of the quality and scope of the learning outcomes they design and their application as goals for learning.

Modeling the behavior of confined colloidal particles under shear flow

We investigate the behavior of colloidal suspensions with different volume fractions confined between parallel walls under a range of steady shears. We model the particles using molecular dynamics (MD) with full hydrodynamic interactions implemented through the use of a lattice-Boltzmann (LB) fluid. A quasi-2d ordering occurs in systems characterized by a coexistence of coupled layers with different densities, order, and granular temperature. We present a phase diagram in terms of shear and volume fraction for each layer, and demonstrate that particle exchange between layers is required for entering the disordered phase.

Locally stable diamond colloidal crystal formed in a cholesteric liquid crystal

We use a Landau de Gennes free energy approach to model a diamond colloidal crystal immersed in a cholesteric liquid crystal. The pitch in our cholesteric is chosen in order to give rise to the most energetically favourable colloid-defect structure, commensurate with the diamond lattice. This structure corresponds to defect lines travelling along symmetry axes in the diamond crystal. By adding noise to the liquid crystal phase we are able to measure the phonon spectrum of our colloidal crystal, which we find to be consistent with a locally stable configuration. Therefore, although it may not correspond to the global minimum energy structure, once formed our diamond lattice should be stable against thermal fluctuations.

Lattice Boltzmann algorithm for three-dimensional liquid-crystal hydrodynamics

We describe a lattice Boltzmann algorithm to simulate liquid-crystal hydrodynamics in three dimensions. The equations of motion are written in terms of a tensor order parameter. This allows both the isotropic and the nematic phases to be considered. Backflow effects and the hydrodynamics of topological defects are naturally included in the simulations, as are viscoelastic effects such as shear-thinning and shear-banding. We describe the implementation of velocity boundary conditions and show that the algorithm can be used to describe optical bounce in twisted nematic devices and secondary flow in sheared nematics with an imposed twist.

Flexoelectric surface switching of bistable nematic devices

We report on a novel method of dynamically controlling the boundary conditions at the surface of a nematic liquid crystal using a surface flexoelectric effect. By moving the surface directors we show that one is able to manipulate defects which lie near the surface. This can be used to produce switching of a nematic liquid-crystal device between two states with very similar free energies. This results in a bistable device that can retain either state with no applied voltage. Switching between the states occurs when the movement of the surface directors rotates those in the bulk which are then able to create or annihilate defects which lie near the surface of the device.

Molecular and continuum boundary conditions for a miscible binary fluid

We show that molecular-dynamics simulations can furnish useful boundary conditions at a solid surface bounding a two-component fluid. In contrast to some previous reports, convective-diffusive flow is consistent with continuum equations down to atomic scales. However, concentration gradients can produce flow without viscous dissipation that is inconsistent with the commonly used Navier slip condition. Also, differential wetting of the two components coupled to a concentration gradient can drive convective flows that could be used to make nanopumps or motors.

Phase ordering in nematic liquid crystals

We study the kinetics of the nematic-isotropic transition in a two-dimensional liquid crystal by using a lattice Boltzmann scheme that couples the tensor order parameter and the flow consistently. Unlike in previous studies, we find that the time dependences of the correlation function, energy density, and number of topological defects obey dynamic scaling laws with growth exponents that, within the numerical uncertainties, agree with the value 1/2 expected from simple dimensional analysis. We find that these values are not altered by the hydrodynamic flow. In addition, by examining shallow quenches, we find that the presence of orientational disorder can inhibit amplitude ordering.

Lattice Boltzmann simulations of liquid crystal hydrodynamics

We describe a lattice Boltzmann algorithm to simulate liquid crystal hydrodynamics. The equations of motion are written in terms of a tensor order parameter. This allows both the isotropic and the nematic phases to be considered. Backflow effects and the hydrodynamics of topological defects are naturally included in the simulations, as are non-Newtonian flow properties such as shear thinning and shear banding.

Equivalence by descent: pedigree analysis with inbreeding and gametic phase disequilibrium

In the presence of gametic phase disequilibrium and inbreeding, multiple locus genotype frequencies cannot be written solely in terms of identity by descent (IBD) probabilities. Following Cockerham & Weir (1973) we introduce the concept of 'equivalence by descent' (EBD), an extension of the concept of IBD to include non-allelic genes. Two genes are said to be EBD if they derive ultimately from the same founding gamete of a pedigree. Allelic genes that are EBD are also IBD. For two loci 11 EBD probabilities, the 'J-coefficients,' are required and for three loci 117 J-coefficients are required to write genotype probabilities. It is shown how the 117 J-coefficients for three loci can be reduced to a basic set of 37. Computer programs, written in the algebraic programming language, MAPLE, are described which are capable of calculating the two- and three-locus J-coefficients for any pedigree, subject only to size limitations. The MAPLE packages are available from the author upon request.

Ionizing radiation and genetic risks. VIII. The concept of mutation component and its use in risk estimation for multifactorial diseases

Multifactorial diseases, which include the common congenital abnormalities (incidence: 6%) and chronic diseases with onset predominantly in adults (population prevalence: 65%), contribute substantially to human morbidity and mortality. Their transmission patterns do not conform to Mendelian expectations. The model most frequently used to explain their inheritance and to estimate risks to relatives is a Multifactorial Threshold Model (MTM) of disease liability. The MTM assumes that: (i) the disease is due to the joint action of a large number of genetic and environmental factors, each of which contributing a small amount of liability, (ii) the distribution of liability in the population is Gaussian and (iii) individuals whose liability exceeds a certain threshold value are affected by the disease. For most of these diseases, the number of genes involved or the environmental factors are not fully known. In the context of radiation exposures of the population, the question of the extent to which induced mutations will cause an increase in the frequencies of these diseases has remained unanswered. In this paper, we address this problem by using a modified version of MTM which incorporates mutation and selection as two additional parameters. The model assumes a finite number of gene loci and threshold of liability (hence, the designation, Finite-Locus Threshold Model or FLTM). The FLTM permits one to examine the relationship between broad-sense heritability of disease liability and mutation component (MC), the responsiveness of the disease to a change in mutation rate. Through the use of a computer program (in which mutation rate, selection, threshold, recombination rate and environmental variance are input parameters and MC and heritability of liability are output estimates), we studied the MC-heritability relationship for (i) a permanent increase in mutation rate (e.g., when the population sustains radiation exposure in every generation) and (ii) a one-time increase in mutation rate. Our investigation shows that, for a permanent increase in mutation rate of 15%, MC in the first few generations is of the order of 1-2%. This conclusion holds over a broad range of heritability values above about 30%. At equilibrium, however, MC reaches 100%. For a one-time increase in mutation rate, MC reaches its maximum value (of 1-2%) in the first generation, followed by a decline to zero in subsequent generations. These conclusions hold for so many combinations of parameter values (i.e., threshold, selection coefficient, number of loci, environmental variance, spontaneous mutation rate, increases in mutation rate, levels of 'interaction' between genes and recombination rates) that it can be considered to be relatively robust. We also investigated the biological validity of the FLTM in terms of the minimum number of loci, their mutation rates and selection coefficients needed to explain the incidence of multifactorial diseases using the theory of genetic loads. We argue that for common multifactorial diseases, selection coefficients are small in present-day human populations. Consequently, with mutation rates of the order known for Mendelian genes, the FLTM with a few loci and weak selection provides a good approximation for studying the responsiveness of multifactorial diseases to radiation exposures.

Ionizing radiation and genetic risks. VII. The concept of mutation component and its use in risk estimation for Mendelian diseases

The responsiveness of Mendelian diseases to an increase in the mutation rate is studied by using the concept of the mutation component (MC) of genetic diseases. Algebraic expressions to evaluate MC at any specific generation following either a one-time or a permanent increase in mutation rate are derived and are illustrated with numerical examples. For a one-time increase in mutation rate, the analysis shows that the first generation MC for autosomal dominant diseases is equal to the selection coefficient; this is also true for X-linked diseases (adjusted for the proportion of X-chromosomes in males). For autosomal recessive diseases the first generation MC is substantially smaller than that for autosomal dominants. In subsequent generations MC gradually decays to zero. Under conditions of a permanent increase in the mutation rate, the MC for autosomal dominant, X-linked and completely recessive autosomal disorders progressively increases to reach a value of one at the new equilibrium. For incompletely recessive autosomal disorders, however, the MC at equilibrium can be larger than one. The rates of approach to the new equilibrium are different for the different classes of diseases, dictated by selection and time (in generations) following radiation exposure. The effects of increases in mutation rate on MC are more pronounced for autosomal dominants, followed by X-linked and are far less for autosomal recessives. Even for autosomal dominants, the early generation effects of radiation exposures would not be appreciable unless the heterozygotes have a severely reduced fitness.

Managing data by phone

Information collection for home care poses more of a problem than it does for institution-based health care organizations. Many versions of smaller computers have been developed, but these pose their own problems. Another technology, already widely available, may be the answer for some agencies.

Alternative fitness models with the same allele frequency dynamics

For any set of one- or two-locus genotypic fitnesses there are alternative sets, usually frequency-dependent and often with quite different biological meanings, that give rise to the same equations for change of allele or haplotype frequencies. Therefore, it is not possible to distinguish among alternative fitness models from allele or haplotype frequency trajectories or equilibrium distributions. For a single locus and for two loci when linkage equilibrium can be assumed, a simple procedure generates some of the alternative fitness sets.

The nonrandom participation of human acrocentric chromosomes in Robertsonian translocations

The present study explores the origin of human Robertsonian translocations (RT) and the causes of the nonrandom participation of the different acrocentrics in them. Satellite associations have been analysed in 966 cells from 8 persons, and 1266 RT with ascertainment have been collected from the literature. The observation that the chromosomes preferentially taking part in satellite associations vary between individuals is confirmed. However, since a preferred chromosome appears to associate at random with the others, this phenomenon should not add to the nonrandomness of the RT. Most RT presumably arise through adjacent chromatid exchanges corresponding to mitotic chiasmata, in the pericentric regions of the acrocentrics. Our working hypothesis is that there is a basic exchange rate between any two acrocentrics. The surplus of t(14q21q) is presumed to depend on these two chromosomes having a homologous pericentric region. The 10-20 times higher incidence of t(13q14q) as compared with other RT is best explained by crossing-over between homologous, but relatively inverted, segments in these chromosomes. Of the 246 RT ascertained through repeated abortions or infertility, 56 were found through the latter. Of these, chromosome 14 was involved in 51. The infertility may be caused by a small deletion of 14q, as is often the case in 15q in Prader-Willi syndrome. In all RT ascertained through 21 or 13 trisomy, respectively, the relevant chromosome is one of the participants. Our data thus do not give any support to the idea of interchromosomal effects exerted by RT.

Mitotic chiasmata, gene density, and oncogenes

Chromosomes with regions rich in mitotic chiasmata in Bloom syndrome (1,3,6,11,12,17,19, and 22) have been compared for various parameters to similar-sized chromosomes 2, 4, 7, 10, 9, 18, 20, and 21 with the following results: (1) The number of genes localized on the test chromosomes is significantly higher (248) than that in the control chromosomes (133). (2) The number of trisomic abortions is significantly lower (45) for the test chromosomes than for the control chromosomes (140). (3) Homogeneously stained regions in neuroblastoma lie at chiasma-containing regions on chromosome arms 1p, 6p, 17q, and 19p or q. (4) The average chiasma density of regions with at least one oncogene is 2.414, whereas that of regions containing no known oncogene is 1.137; however, the difference is not statistically significant. The association of constant cancer chromosome breaks is also in the positive direction, but is not statistically significant. Our tentative conclusion is that the chiasma-rich regions which are Q-dark and early-replicating, and therefore assumed to contain active "housekeeping" genes are extended in interphase. Thus they are available for mitotic crossing-over. In the trisomic state they act as trisomy lethals, leading to early abortions. Being gene-rich they are more likely to contain oncogenes which is reflected also in their agreement with cancer breakpoints. The very high incidence of cancer in Bloom syndrome is a further indication of the possible association of cancer-related phenomena and mitotic crossing-over.

X chromatin, endomitoses, and mitotic abnormalities in human cervical cancer

The incidence of X chromatin bodies and mitotic modifications and aberrations has been analyzed using Feulgen-squash preparations in 47 cervical cancers from Helsinki and 35 from Madison. Sixteen of the 82 tumors did not display any X chromatin bodies, and some others showed a lower than normal frequency, especially in the large nuclei. Different hypotheses to explain the absence of Barr bodies in female tumors have been reviewed. A new observation is that 44/82 tumors contained endomitoses. The metaphase/prophase ratio (M/P) was higher than 1.5 in all but three cases, reaching values as high as 23.0 (Madison) and 34.2 (Helsinki), and in one exceptional case, 51.8. The different types of cells, mitotic, endomitotic, and those with large to giant nuclei, form their own strands or layers. Cervical cancer is diagnosed earlier in Finland than in Madison due to a Pap mass screening program, and consequently, the survival of the patients after 5 years was 27/47 in Helsinki and 6/35 in Madison. No correlation could be established between the M/P (or other mitotic phenomena) or the stage and grade of the tumor, the age of the patient, or survival time.

Are human studies possible? Some thoughts on the mutation component and population monitoring

The concept of the mutation component of a genetic trait is discussed and its relation to heritability investigated. It is found that for qualitative traits held in the population by opposing directional selection and mutation, the mutation component equals the broad sense heritability. The mutational component of a quantitative trait with an intermediate optimum is found generally to be between half and one times the (narrow sense) heritability of the character. Although more work on this matter is required, the finding of a relationship between mutation component and heritability should allow us to make better predictions regarding the likely impact of an increased mutation rate on the human population. Some statistical problems relevant to the detection of an increased mutation rate are also discussed.

Genetic polymorphism of PIF (parotid isoelectric focusing variant) proteins with linkage to the PPP (parotid proline-rich protein) gene complex

Genetic polymorphism is found among the PIF (parotid isoelectric focusing variant) salivary proteins after separation by prolonged isoelectric focusing in pH 3.5-5.2 urea polyacrylamide slab gels subsequently stained for protein. Two PIF proteins are either present (PIF+) or absent (PIF-) from all salivas. The phenotypes are determined by autosomal inheritance of two alleles, PIF+ and PIF-. Gene frequencies in randomly collected samples show marked racial differences: among 148 whites, PIF+ is 0.66 and PIF- is 0.34; among 90 blacks, PIF+ is 0.35 and PIF- is 0.65; among 78 Chinese, PIF+ is 0.56 and PIF- is 0.44. Studies in 41 families including 129 children support the interpretation of control of PIF by a single autosomal locus. In 8 PIF+ X PIF- matings, there were 8 PIF- (6.34 expected) children. In 33 PIF+ X PIF+ matings, there were 7 PIF- (6.70 expected) children. Linkage studies indicate that PIF is closely linked to the proline-rich protein (PPP) gene complex (e.g., for six families, lod score at theta = 0.00 of PIF/Gl is 3.58). In 107 randomly collected samples from whites, PIF is strongly associated with Db (chi 2(1) = 20.02; P less than 0.0001) and Gl (chi 2(1) = 12.58; P = 0.0005) but not with Pr, Ps, Pm, and Pa proteins. These data (probably reflecting genetic disequilibrium) suggest that PIF may be closer to Db and Gl than to other identified loci of the PPP gene complex. The PPP gene complex includes at least seven genes (and probably more) that produce many acidic and basic proline-rich proteins, constituting about two-thirds of parotid salivary proteins that are thought to have important functions at the tooth surfaces.

The mutation component of genetic damage

The mutation component, M, is a measure of the proportion of the impact of a genetic condition that is attributable to recurrent mutation. For a trait maintained by balance between mutation and directional selection, M is approximately the broad-sense heritability; for a measured character where the mean and optimum coincide, M is about half the heritability. If the narrow-sense heritability is high, the impact changes relatively rapidly with a change in mutation rate. If the narrow-sense heritability is low, M cannot be predicted, but the change in impact following a change in mutation rate, if any, is very slow.

Determining antigenic relationships on the basis of MLC testing. II. Mechanical algorithms

We describe mechanical algorithms, involving manipulations of matrices, for listing all possible antigenic relationships among individuals tested in MLC. We also describe an algorithm for determining whether an MLC result can be interpreted in line with our assumption of the preceding paper, that stimulation occurs if, and only if, the stimulator has antigen(s) foreign to the responder.

Determining antigenic relationships on the basis of MLC testing. I. A matrix approach for listing all possible antigenic assignments

We present an approach for determining all possible antigenic relationships among a group of individuals, on the basis of MLC results. We assume that the researcher or tissue typer has a criterion for classifying responses into positives and negatives, and that this classification has already been done for the data set being considered. Given any set of positive and negative MLC responses, our technique produces all antigenic assignments consistent with the assumption that a response occurs if and only if the stimulator has antigen(s) foreign to the responder. No genetic assumptions are made.

Polymorphism of Ps (parotid size variant) and detection of a protein (PmS) related to the Pm (parotid middle band) system with genetic linkage of Ps and Pm to Gl, Db, and Pr genetic determinants

Genetic polymorphism of the Ps (parotid size variant) proteins found in saliva is determined by autosomal inheritance of two expressed and one unexpressed allele. This hypothesis is supported by studies in 43 families including 153 children. Gene frequencies determined for 150 randomly collected salivas from whites and 101 randomly collected salivas from blacks are as follows: for whites, Ps1 = 0.598, Ps2 = 0.101, Ps0 = 0.301; for blacks, Ps1 = 0.185, Ps2 = 0.126, and Ps0 = 0.689. The electrophoretic polymorphism is manifested by apparent differences in molecular weights between Ps proteins. The Ps proteins are glycosylated and have an approximate isoelectric point of pI 8.1 as determined by isoelectric focusing in gels. We have also found in saliva the presence of a protein (PmS) which shows strong positive correlations with the presence of the smaller sized Pm (PmF) salivary protein described by Ikemoto et al. (1977). This suggested that PmS is probably part of the Pm protein polymorphic system. For randomly collected salivas from whites, the gene frequencies are PmF+ = 0.15 (N = 140) and PmS+ = 0.12 (N = 150). For randomly collected salivas from blacks, the gene frequency is PmS+ = 0.24 (N = 101). The gene frequency of PmF+ was not determined. Family studies support autosomal inheritance of PmF and PmS.

X chromosome constitution and the human female phenotype

The correlations of abnormal X chromosome constitutions and the resulting phenotypes in the human female are reviewed. The following hypotheses put forward to explain these correlations are discussed in detail: (1) The damage is done before X inactivation; (2) An effect is exerted between reactivation of the X chromosome(s) and meiosis in oocytes; (3) A recessive gene(s) in hemizygous condition might be expressed in the cases in which the same X is active in all cells; (4) A change in the number of presumed active regions on the inactive X chromosomes might have an effect; (5) A position effect, in that the region Xq13-q27 has to be intact in both X chromosomes to allow normal development, may be responsible; (6) An effect during the period when cells with different inactivation patterns compete is a probability; (7) The original X inactivation may be neither regular nor random. The conclusion reached is that the phenotypic effects of a specific X chromosome aberration may be simultaneously exerted through different pathways (Tables 1 and 2). Hypotheses (2), (4), (5), and (6) are considered probable. Hypothesis (3) has been discarded, and there is very little evidence for hypotheses (1) and (7).

Genetic polymorphism of vitamin B12 binding (R) proteins of human saliva detected by isoelectric focusing

Genetic polymorphism of the vitamin B12 binding (R) proteins of parotid saliva is determined by autosomal inheritance of codominant alleles. This hypothesis is supported by studies in 43 families including 152 children. For randomly collected salivas from 143 whites, 104 blacks, and 75 Chinese, gene frequencies are as follows: for whites, Rs1=0.88, Rs2=0.12; for blacks, Rs1=0.94, Rs2=0.06; for Chinese, Rs1=1.00. This genetic marker is also shared by R proteins of milk, tears, and leukocytes. In the Rs 1--2 salivary type there is less labeling of the protein products of Rs2 v. Rs1 with 57Co B12 as assessed by the intensity of the bands on the autoradiogram. There is no evidence for close linkage (theta less than 0.01) between Rs and TC II (transcobalamin II) or between Rs and salivary protein locus Pr, Db, Gl, or Ps.

Position of the human X inactivation center on Xq

In three women with a 46,XXq- chromosome constitution, the length of the deletion was expressed as the ratio of the remaining part of Xq to Xp c' over a + b. In one of them (KH) this ratio was 0.33, in another (GE) 0.59, and in the third (AP) the ratio fell between these values. The break in KH is more or less on the border of the Q-dark proximal region. A comparison with relevant X-autosomal translocations indicates that the X inactivation center lies near, but not at the border of, the Q-dark and the adjoining bright region (c and d).

Genetic polymorphism of the major parotid salivary glycoprotein (Gl) with linkage to the genes for Pr, Db, and Pa

Genetic polymorphism of the major glycoprotein (Gl) found in parotid saliva is determined by autosomal inheritance of one unexpressed and four expressed alleles. This hypothesis is supported by studies in 41 white families including 146 children. For 143 randomly collected salivas from whites and 82 randomly collected salivas from blacks, maximum likelihood estimates of the gene frequencies are as follows: for whites, Gl1 = 0.742, Gl2 = 0.040, Gl3 = 0.155, Gl4 = 0.017, Gl0 = 0.46; for blacks, Gl1 = 0.459, Gl2 = 0.050, Gl3 = 0.337, Gl4 = 0.044, Gl0 = 0.110. There is strong evidence for linkage of Gl/Pr (seven families, lod score at theta = 0 is 5.24) and G1/Db (eight families, lod score at theta = 0 is 4.45). The allelic products of Gl show evidence for linkage disequilibrium with the products of the Pr, Db, and Pa loci (P less than 0.0005). On the basis of varying degrees of linkage disequilibrium, Gl may be closer to Db than to Pr or Pa and on the "outside" of Db with respect to Pr or Pa. Amino acid analyses of Gl 1 and Gl 4 proteins show strong resemblances in composition to the major basic glycoprotein and the acidic proline-rich proteins of parotid saliva described by other workers. The polymorphic forms of the Gl proteins show microheterogeneity due to variability in charge and molecular weight. The electrophoretic polymorphism appears to be determined by apparent differences in molecular weights between the Gl proteins.

Mitotic chiasmata in human diplochromosomes

Three placental tissue cultures of spontaneous human abortions showed an unusually high frequency of metaphases with diplochromosomes. In 62 such cells, nine configurations were interpreted as mitotic chiasmata between the two sister chromosomes of a diplochromosome. One U-type exchange between two sister chromosomes was also found. This differs significantly from the 1 : 1 ratio of adjacent and alternate exchanges in translocations, thus supporting the idea that mitotic chiasmata are in principle different from chromatid translocations. The hypothesis is put forward that the frequency of homologous exchanges is determined by the intimacy of pairing which ranges from meiotic pairing through sister chromatid association, through sister chromosome association in diplochromosomes to accidental pairing of homologous regions in diploid cells.

An incorrect definition of fitness revisited

I have attempted to show that a certain mistaken definition of fitness, which surfaces occasionally, may turn out to have some merit. No claim is made that it is an improvement on, or should replace, the conventional definition of fitness; but it is different and has its own validity. Its generality is intriguing, its application is not limited either to selection or one locus models, and it may be easier to measure experimentally.

Nonpairing of the X and Y chromosomes in the spermtocytes of BDF1 mice

In the hybrid mouse strain BDF1, some 35--40% of spermatocytes had unpaired X and Y choromosomes in stages ranging from diplotene to first meiotic metaphase. This phenomenon varied significantly from mouse to mouse. In pooled material from Swiss Albino and CF1 mice, the corresponding frequency was 5.7%. In C57 BL/6 mice, one of the parent strains of BDF1 mice, the X and Y were separate in 7.7% of the spermatocytes. Based on the behavior of the X and Y in the BDF1 strain, it is concluded that they do not pair, rather than initially pairing and then precociously separating. The factor interfering with the pairing of the X and Y does not affect the autosomes; possibly it is an incompatibility of the two sex chromosomes, which come from different inbred lines.

A possible active segment on the inactive human X chromosome

An idic(Xp--) in which the two X chromosomes are attached short arm to short arm, and which thus has two b regions (the Q-dark segment next to the centromere on Xp) between the inactivation centers, assumed to be situated on the Q-dark region next to the centromere on Xq, showed 63.8% bipartite Barr bodies as compared with 22.2% formed by idic(Xq--). In addition, the mean distance of the two parts of the Barr bodies in the fibroblasts of a patient with idic(Xp--) is significantly greater than in the cases with one or no b region. Contrary to the other patients with abnormal X chromosomes, the buccal cells of a woman idic(Xp--) showed a number of bipartite Barr bodies. -- To explain these observations we have put forward the hypothesis that the b region on the Xp always remains active and thus, when the rest of the chromosome forms a Barr body, this segment is extended, allowing the two parts of the X chromatin to get farther apart and at the same time increasing the percentage of bipartite bodies.