MATERNAL INHERITANCE OF CONDITION AND CLUTCH SIZE IN THE COLLARED FLYCATCHER

Maternal effects may strongly influence evolutionary response to natural selection but they have been little studied in the wild. We use a novel combination of experimental and statistical methods to estimate maternal effects on condition and clutch size in the collared flycatcher, where we define “condition” to be the nongenetic component of clutch size. We found evidence of two maternal effects. The first (m) was the negative effect of mother's clutch size on daughter's condition, when mother's condition was held constant. The second (M) was the positive effect of mother's condition on daughter's condition, when mother clutch size was held constant. These two effects oppose one another because mothers in good condition also lay many eggs. The maternal effects were large: Experimentally adding an egg to a mother's nest reduced clutch sizes of her daughters by 1/4 egg (i.e., m = -0.25). Measured degree of resemblance between mother and daughter clutch sizes yielded M = 0.43. The results weakly support the presence of heritable genetic variation in clutch size: additive genetic variance/total phenotypic variance = 0.33. This estimate was highly variable probably because, as we show, mother-daughter resemblance may depend hardly at all on the amount of genetic variance when maternal effects are present. Daughter-mother regression (a standard method for estimating heritability) is consequently a poor guide to the amount of genetic variance in clutch size. Our results emphasize the value of combining field experiments with observations for studying inheritance.     

In Lieu of an Introduction

Nikolai Veresov: Tatiana, in this volume of our journal we publish a selection of your articles. Two of your other articles were published in Soviet Psychology in the 1970s. Introducing you to the readers of that journal, James Wertsch (1978) wrote: "The author … is one of the leading young investigators from the Luria school of neurolinguistics. She has studied and conducted extensive research both with Luria and with A. A. Leontiev, a major figure in Soviet psycholinguistics. Her analysis of inner speech as a mechanism in speech production reveals the strong influence that L. S. Vygotsky has had on Soviet psychology."¹ But first of all, I suppose our readers would be interested in learning more about your life, about events that preceded your scientific achievements. Could you please tell us briefly about your childhood and your family? How did your parents influence your course of life and your occupational choice? What did they do?     

Genomic triumph meets clinical reality

A report on the ''Genomic Disorders 2013: from 60 years of DNA to human genomes in the clinic'' meeting, held at Homerton College, Cambridge, UK, April 10-12, 2013.A meeting about genetics held in April 2013 in Cambridge, UK, started laden with historical overtones: it was 60 years to the month since the structure of DNA was reported as a result of work carried out by Watson and Crick just a short walk away. This year''s Genomic Disorders 2013 meeting was thus subtitled ''From 60 years of DNA to human genomes in the clinic'' and reflected on both the spectacular progress that has been achieved in these six decades, and also on the barriers to further advances.It has indeed been a remarkable journey. Progress in sequencing technologies has led to near-complete genome sequences of thousands of humans at a fraction of the cost of the Human Genome Project and prompted the push into clinical medicine, always a goal of the project. Within a working lifetime, the field had made a dramatic transition, likened to that from medieval guild to modern factory (Richard Durbin, The Wellcome Trust Sanger Institute, UK) or from the first car (which had to be preceded by a man walking with a red flag) towards the modern automobile industry (Robert C Green, Brigham and Women''s Hospital and Harvard Medical School, USA).In addition to celebrating the past, the major stumbling blocks on the road to clinical medicine came up during several rounds of discussions and are a main focus of this report. The challenges can be grouped as technological, annotation-related, biological or ethical, and seem to increase in difficulty and complexity in that order.     

THE DETERMINATION OF 'BEST INTERESTS' IN RELATION TO CHILDHOOD VACCINATIONS (published in Bioethics 19(1))

ERRATUM

We regret that, due to a technical error, the uncorrected version of Angus Dawson's article was printed in 19:1. We apologise to the author and reprint in full the corrected version of the paper on the following pages. Dawson, A. et al. The Determination of the Best Interests in Relation to Childhood Immunisation . Bioethics 2005 ; 19 : 72 – 89 .

ABSTRACT

There are many different ethical arguments that might be advanced for and against childhood vaccinations. In this paper I will explore one particular argument that focuses on the idea that childhood vaccinations are justifiable because they are held to be in the best interests of a particular child. Two issues arise from this idea. The first issue is how best interests are to be determined in the case of childhood vaccinations. The second issue is what follows from this to justify potential interventions within the family in relation to such vaccinations. I argue that best interests must be characterised objectively in such situations and that this means that, in at least some cases, parental decision‐making about vaccinating their children may be overridden.

     

Relationships Between Kendall's Coefficient of Concordance and a Nonparametric Measure of Phenotypic Stability with Implications for the Consistency in Rankings as Affected by Variance Components

For a two-way classification with rows (= genotypes) and columns (= environments) relationships between Kendall's coefficient of concordance W and a nonparametric measure of phenotypic stability S (= variance among the ranks over the environments) are presented. This provides an analogy between Wricke's ecovalence and the sum of squares of genotype-environment interactions on the parametric side and S and Kendall's W on the nonparametric side: S is a genotype's contribution to the discordance (1 — W) in the data set, while Wricke's ecovalence is a genotype's contribution to the genotype-environment interaction sum of squares. Genotype x environment interactions may lead, but must not necessarily lead to non-identical rank orders of the genotypes in different environments (crossover versus noncrossover interactions). When does interaction become rank interaction? The similarity of the rank orders (measured by W) can be approximately expressed by the ratio of the genotypic variance and sum of genotypic variance plus residual variance. For the consistency of rankings this relation leads to an approximate test of significance which is based on variance components. Finally, a numerical example is given using grain yield data of 20 genotypes (varieties) of winter wheat in 10 environments (locations) from German registration trials.     

Gendered perceptions on infant feeding in Eastern Uganda: continued need for exclusive breastfeeding support

Background

In resource-poor settings, HIV positive mothers are recommended to choose between 'Exclusive breastfeeding' (EBF) or 'Exclusive replacement feeding' (ERF). Acceptability, Feasibility, Affordability, Sustainability and Safety (AFASS) has been the World Health Organization (WHO)'s a priori criteria for ERF the last ten years. 'AFASS' has become a mere acronym among many workers in the field of prevention of mother-to-child transmission of HIV, PMTCT. Thereby, non-breastfeeding has been suggested irrespective of social norms. EBF for the first half of infancy is associated with huge health benefits for children in areas where infant mortality is high. But, even if EBF has been recommended for a decade, few mothers are practicing it. We set out to understand fathers' and mothers' infant feeding perceptions and the degree to which EBF and ERF were 'AFASS.'

Methods

Eight focus groups with 81 informants provided information for inductive content analysis. Four groups were held by men among men and four groups by women among women in Mbale District, Eastern Uganda.

Results

Two study questions emerged: How are the different feeding options understood and accepted? And, what are men's and women's responsibilities related to infant feeding? A mother's commitment to breastfeed and the husband's commitment to provide for the family came out strongly. Not breastfeeding a newborn was seen as dangerous and as unacceptable, except in cases of maternal illness. Men argued that not breastfeeding could entail sanctions by kin or in court. But, in general, both men and women regarded EBF as 'not enough' or even 'harmful.' Among men, not giving supplements to breast milk was associated with poverty and men's failure as providers. Women emphasised lack of time, exhaustion, poverty and hunger as factors for limited breast milk production. Although women had attended antenatal teaching they expressed a need to know more. Most men felt left out from health education.

Conclusion

Breastfeeding was the expected way to feed the baby, but even with existing knowledge among mothers, EBF was generally perceived as impossible. ERF was overall negatively sanctioned. Greater culture-sensitivity in programs promoting safer infant feeding in general and in HIV-contexts in particular is urgently needed, and male involvement is imperative.

Trial Registration

The study was part of formative studies for the ongoing study PROMISE EBF registered at http://clinicaltrials.gov (NCT00397150).     

The Life Cycle of Trypanoplasma bullocki (Zoomastigophorea: Kinetoplastida)1

The leech Calliobdella vivida (Verrill) is the vector of Trypanoplasma bullocki. At 10°C, infective-stage flagellates were first present in the leech's proboscis sheath five days after feeding. At 5°C, infective-stage flagellates were not present in the leech's proboscis sheath until 10 days after feeding, but at 20°C, flagellates were located there as early as 24 h after feeding. Infected leeches retained flagellates through three subsequent feeds on uninfected fish. When flagellates were first observed in hogchoker, Trinectes maculatus (Bloch & Schneider), they were much larger than infective stages from the leech. Average flagellate length then decreased during early acute phase, but gradually increased thereafter. Peak parasitemia was greater in a hogchoker inoculated by only one leech but held at colder temperature than in a hogchoker inoculated by 45 leeches, suggesting that temperature may be more important than inoculum in determining peak parasitemia. Cell division in the fish host is described. SEM studies of fish blood flagellates revealed a pre-oral ridge and a cytostome.     

Estimation of the stage-specific survival rate in the insect population with overlapping stages

An application ofHokyo andKiritani 's method (1967) was attempted to estimate the stage specific survival rates of the population with overlapping stages. This method can be written as follows assuming a constant daily survival rate (K) throughout the life: where, and F refer respectively to the total incidence of ith instar nymphs and that of individuals after ith instar inclusive, and α_i refers to the developmental period of ith instar. Application of this model to caged and natural populations of the southern green stink bug, Nezara viridula, was made to test its validity. The estimates of the initial number of successive stages obtained from the present method were compared with those fromRichards andWaloff 's method (1954) for the caged populations of 1st, 2nd and 3rd generations. The superiority of the present method to theRichards andWaloff 's in estimating adult numbers was shown in all the generations examined. When different daily survival rates are involved in the course of population decrease, application of the revised method proposed byHokyo andKiritani (1967), gives much reliable estimate as compared with one before correction. The present method is useful in constructing life table of such species as scale insects which complete their life cycle within a defined space, but their successive stages overlap considerably.     

Chronicle of a summer and the editing of cinema‐verite

Jean Rouch and Edgar Morin's Chronicle of a Summer is held up as an innovative, seminal “work in the formation of cinéma‐vérité, and has a central position in the development of documentary and ethnographic filmmaking. Although much has been written about fthis film, little attention has been paid to the film's construction. This paper examines ‘elements of the editing structure of Chronicle of a Summer both to consider how this “work was shaped given the constraints of its production and intended reception and to ¦ analyze a relatively neglected aspect of documentary film practice.     

Exploring Jordan's rule in Pacific three‐spined stickleback Gasterosteus aculeatus

Coastal marine Gasterosteus aculeatus were captured from seven locations along the Pacific coast of North America, ranging across 21·8° latitude to test Jordan's rule, i.e. that vertebral number should increase with increasing latitude for related populations of fish. Vertebral number significantly increased with increasing latitude for both total and caudal vertebral number. Increasing length with latitude (sensu Bergmann's rule) was also supported, but the predictions for Jordan's rule held when controlling for standard length. Pleomerism was weakly evidenced. Gasterosteus aculeatus exhibited sexual dimorphism for Jordan's rule, with both sexes having more vertebrae at higher latitudes, but only males showing a positive association between latitude and the ratio of caudal to abdominal vertebrae. The number of dorsal‐ and anal‐fin rays and basals increased with increasing latitude, while pectoral‐fin ray number decreased. This study reinforces the association between phenotypic variation and environmental variation in marine populations of G. aculeatus.     

The historical ecology of the large mammal populations of Ngorongoro Crater,Tanzania, east Africa

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Population genomics from pool sequencing

Next generation sequencing of pooled samples is an effective approach for studies of variability and differentiation in populations. In this paper we provide a comprehensive set of estimators of the most common statistics in population genetics based on the frequency spectrum, namely the Watterson estimator , nucleotide pairwise diversity Π, Tajima's D, Fu and Li's D and F, Fay and Wu's H, McDonald‐Kreitman and HKA tests and , corrected for sequencing errors and ascertainment bias. In a simulation study, we show that pool and individual θ estimates are highly correlated and discuss how the performance of the statistics vary with read depth and sample size in different evolutionary scenarios. As an application, we reanalyse sequences from Drosophila mauritiana and from an evolution experiment in Drosophila melanogaster. These methods are useful for population genetic projects with limited budget, study of communities of individuals that are hard to isolate, or autopolyploid species.     

An Unbalanced Mixed Model with Random Effects Having Unequal Variances

Consider the mixed model where x_ijk's are known constants, β_k are unknown parameters and a_i, e_ij are random variables independently and normally distributed with zero means and variances σd_i and σ² respectively, where it is assumed that the d_i's are known (d_i >0). This paper presents procedures for estimating the variance components σ, σ², for testing the hypothesis σ = 0, and for making transformations to random variables with uncorrelated errors and constant variances in order to estimate as well as to test hypothesis concerning the β_k's in the model.     

Egg-laying differences in two grey partridge (<Emphasis Type="Italic">Perdix perdix</Emphasis> L.) lines subject to different breeding technology: artificial egg hatch or mother egg hatch

Artificial breeding bypasses the effect of natural selection and, inevitably, subjects game birds to selection by breeding technology. For this reason, we evaluated whether different breeding technologies, carried out for six generations, were enough to differentiate two grey partridge lines. Two lines of grey partridges, obtained from the same population, were used: the animals of the line broody had been hatched directly by their own mothers for six generations; the animals of the line incubator had always been hatched in incubators from eggs laid by cage-reared grey partridges. Offspring from the two lines were reared under the same conditions and 2 years of production were monitored. Results showed that grey partridges of the broody line had a shorter and delayed laying period and, consequently, a lower egg production than the incubator line. In the first year of production, mean length of laying period 58 vs. 75 days, p<0.01; mean start of egg production through photostimulation: 61 vs. 42 days, p<0.01; mean number of eggs laid: 46 vs. 58, p<0.01. In the second year: mean length of laying period, 63 vs. 66 days, p<0.05; mean start of first egg production through photostimulation: 51 vs. 45 days, p<0.05; mean number of eggs laid: 45 vs. 56, p<0.01.     

Trends in the captive breeding of threatened and endangered birds in British zoos, 1988–1997

The aim of this study was to assess trends in captive breeding of threatened and endangered bird species in British zoos. The measures we recorded were: 1) the total number of species held, 2) the percentage of species held that are listed in the IUCN Red List, 3) the percentage of endangered species breeding, and 4) the number of species in managed breeding programs. These data were gathered from the bird inventories of 10 representative British zoos for the years 1988 and 1997. The data for measures 1–3 were compared between the 2 years using a Wilcoxon matched‐pairs test. We found that the zoos maintained the same number of species (W=10.5; n=10; P=0.093; median=87.5 and 78 for 1988 and 1997, respectively). However, there was a significant increase in the number of birds held that fit each of the IUCN's conservation categories (Endangered: W=43.0; n=10; P<0.05, median=1.48 and 6.64 for 1988 and 1997, respectively; Vulnerable: W=53.0; n=10; P<0.05, median=3.33 and 10.05 for 1988 and 1997, respectively; and Rare: W=55.0; n=10; P<0.01, median=0.00 and 8.33 for 1988 and 1997, respectively). Overall, the percentage of threatened species kept in zoos increased from a median of 4.81 in 1988 to 25.02 in 1997. During this period there was an increase in the number of species in each category of the IUCN Red List. No difference was found in the number of threatened species breeding between 1988 and 1997. Zoo Biol 23:85–89, 2004. © 2004 Wiley‐Liss, Inc.     

Kinetics of ethidium's intercalation in packaged bacteriophage T7 DNA: effects of DNA packing density

The kinetics of ethidium's intercalative binding to DNA packaged in bacteriophage T7 and two T7 deletion mutants have been determined, using enhancement of fluorescence to quantitate binding. At a constant ethidium concentration, the results can be described as first-order binding with two different rate constants, k (= k₁ + k_?1) and k (= k₂ + k_?2). The larger rate constant (k) was at least four orders of magnitude smaller than the comparable first-order forward rate constant for binding to DNA released from its capsid. At 25°C values of k decreased as the amount of DNA packaged per internal volume increased. This latter observation indicates that the rate of ethidium's binding to packaged T7 DNA is limited by an event that occurs inside of the DNA-containing region of T7, not by the crossing of T7 capsid's outer shell. Arrhenius plots of kM are biphasic, indicating a transition for packaged DNA at a temperature of 20°C. The data indicate that k s are limited by either sieving of ethidium during its passage through the packaged DNA or subsequent hindered intercalation.     

History of orchid propagation: a mirror of the history of biotechnology

Part I Orchid seeds are nearly microscopic in size. Because of that, many fanciful theories were proposed for the origin of orchids. Almost 400 years separate the time when orchid seeds were seen for the first time and the development of a practical asymbiotic method for their germination. The seeds were first observed and drawn during the sixteenth century. Seedlings were first described and illustrated in 1804. The association between orchid and fungi was observed as early as 1824, while the requirement for mycorrhiza for seed germination was established in 1899. An asymbiotic method for orchid seed germination was developed in 1921. After Knudson’s media B and C were formulated, orchids growing and hybridization became widespread. Hybrids which early growers may not have even imagined became possible. Part II A commonly held view is that Prof. Georges Morel is the sole discoverer of orchid micropropagation and that he was the first to culture an orchid shoot tip in 1960. In fact, the first in vitro orchid propagation was carried out by Dr. Gavino Rotor in 1949. Hans Thomale was the first to culture an orchid shoot tip in 1956. The methods used by Morel to culture his shoot tips were developed by others many years before he adapted them to orchids. This review also traces the history of several techniques, additives, and peculiarities (agitated liquid cultures, coconut water, banana pulp, a patent and what appears to be an empty claim) which are associated with orchid micropropagation. A summary of plant hormone history is also outlined because micropropagation could not have been developed without phytohormones.

Chemico‐mechanical imaging of Barrett's oesophagus

Barrett's oesophagus is a condition characterized by a change in the lining of the oesophagus that markedly increases the risk of adenocarcinoma. We demonstrate the first site‐matched application of Brillouin microscopy, Raman microscopy and FTIR micro‐spectroscopic imaging to ex‐vivo epithelial tissue – Barrett's oesophagus. The mechanical and chemical characters of the epithelium were assessed in histological sections from a patient subjected to endoscopic oesophageal biopsy. Previous studies have shown that both these properties change within the oesophageal wall, owing to the presence of distinct cellular and extracellular constituents which are putatively affected by oesophageal cancer. Brillouin microscopy enables maps of elasticity of the epithelium to be obtained, whilst Raman and FTIR imaging provide ’chemical images' without the need for labelling or staining. This site‐matched approach provides a valuable platform for investigating the structure, biomechanics and composition of complex heterogeneous systems. A combined Brillouin‐Raman device has potential for in‐vivo diagnosis of pathology.

First application of site‐matched micro Brillouin, Raman and FTIR spectroscopic imaging to epithelial tissue in Barrett's oesophagus