bluuebunny/crossref_metadata_2025 huggingface dataset:
How women migrants cope with their labour experience: The case of Eastern European women working on strawberry farms in Spain
Authors: Luque-Ribelles Violeta , Palacios-Gálvez María Soledad , Morales-Marente Elena
Published: October 2018

The aim of this study is to know how migrant women from eastern Europe (hereinafter EE) define their migratory experience and how they face it. They were interviewed 25 women who work in the strawberry fields of Huelva (southwest of Spain). The phenomenon is approached from Liberation Psychology (LP) and qualitative methodology. LP emphasises power, as one of the core components of the migration experience, this concept has guided the interpretation of the findings. In-depth interviews with individuals and groups, comprising migrant women from Romania and Bulgaria, were conducted. A thematic analysis was performed which allowed us to identify the key themes running through their narratives. These have been grouped into three areas: the mechanisms of oppression, sources of power, and coping with oppression. In a bid to enhance the well-being of female migrant workers and levels of social justice several are proposed to giving workers better, more comprehensive information about the migration process; facilitating a redefinition of the concept of migration; and providing cultural competence training for employers as part of social policy are discussed.
Determination of the tactical athlete level of a high-performance tennis team and subjective assessment of the coach
Authors: Aburachid Layla Maria Campos , Mendes Breno Tavares Perdigão , Mazzardo Tatiane , Monteiro Gabriella Nelli , Araújo Nayanne Dias , Greco Pablo Juan
Published: October 2018

The objective of the study was to evaluate the level of tactical knowledge of a high-performance tennis team, considering gender, age, category, and year in the category, years of practice and participation in competitions. There was also a subjective evaluation by two coaches on the level of athletic performance of their athletes, as well as that of the athletes themselves. In the sample, there were 37 athletes, 23 men and 14 women at ages between 11 and 18 years old (14.10 ± 1.90). In order to determine the level of athletic performance of the athletes, the test of declarative tactical knowledge (DTK) in tennis was used. The variables to differentiate the level of tactical performance were gender (female achieved better scores: p=0.004, F = 2.242), the category (better scores for 18 years old compared to 12 years old: p=0.007, F= 4.223) and the experience in state competitions (p = 0.042, F = 3.059). It was observed that 73% of the tennis teams had their level of tactical performance, via DTK, classified as good or very good. In the subjective evaluation, the coach underestimated the tactical level of 48.6% of his athletes, while 75.7% of the athletes overestimated their own knowledge. In this study, it was verified that factors like gender, category and experience in state competitions differentiated the level of tactical performance.
The subiculum is a patchwork of discrete subregions
Authors: Cembrowski Mark S , Wang Lihua , Lemire Andrew L , Copeland Monique , DiLisio Salvatore F , Clements Jody , Spruston Nelson
Published: October 2018

In the hippocampus, the classical pyramidal cell type of the subiculum acts as a primary output, conveying hippocampal signals to a diverse suite of downstream regions. Accumulating evidence suggests that the subiculum pyramidal cell population may actually be comprised of discrete subclasses. Here, we investigated the extent and organizational principles governing pyramidal cell heterogeneity throughout the mouse subiculum. Using single-cell RNA-seq, we find that the subiculum pyramidal cell population can be deconstructed into eight separable subclasses. These subclasses were mapped onto abutting spatial domains, ultimately producing a complex laminar and columnar organization with heterogeneity across classical dorsal-ventral, proximal-distal, and superficial-deep axes. We further show that these transcriptomically defined subclasses correspond to differential protein products and can be associated with specific projection targets. This work deconstructs the complex landscape of subiculum pyramidal cells into spatially segregated subclasses that may be observed, controlled, and interpreted in future experiments.
Zygotic gene activation in the chicken occurs in two waves, the first involving only maternally derived genes
Authors: Hwang Young Sun , Seo Minseok , Kim Sang Kyung , Bang Sohyun , Kim Heebal , Han Jae Yong
Published: October 2018

The first wave of transcriptional activation occurs after fertilisation in a species-specific pattern. Despite its importance to initial embryonic development, the characteristics of transcription following fertilisation are poorly understood in Aves. Here, we report detailed insights into the onset of genome activation in chickens. We established that two waves of transcriptional activation occurred, one shortly after fertilisation and another at Eyal-Giladi and Kochav Stage V. We found 1544 single nucleotide polymorphisms across 424 transcripts derived from parents that were expressed in offspring during the early embryonic stages. Surprisingly, only the maternal genome was activated in the zygote, and the paternal genome remained silent until the second-wave, regardless of the presence of a paternal pronucleus or supernumerary sperm in the egg. The identified maternal genes involved in cleavage that were replaced by bi-allelic expression. The results demonstrate that only maternal alleles are activated in the chicken zygote upon fertilisation, which could be essential for early embryogenesis and evolutionary outcomes in birds.
Reversal of ApoE4-induced recycling block as a novel prevention approach for Alzheimer’s disease
Authors: Xian Xunde , Pohlkamp Theresa , Durakoglugil Murat S , Wong Connie H , Beck Jürgen K , Lane-Donovan Courtney , Plattner Florian , Herz Joachim
Published: October 2018

ApoE4 genotype is the most prevalent and also clinically most important risk factor for late-onset Alzheimer’s disease (AD). Available evidence suggests that the root cause for this increased risk is a trafficking defect at the level of the early endosome. ApoE4 differs from the most common ApoE3 isoform by a single amino acid that increases its isoelectric point and promotes unfolding of ApoE4 upon endosomal vesicle acidification. We found that pharmacological and genetic inhibition of NHE6, the primary proton leak channel in the early endosome, in rodents completely reverses the ApoE4-induced recycling block of the ApoE receptor Apoer2/Lrp8 and the AMPA- and NMDA-type glutamate receptors that are regulated by, and co-endocytosed in a complex with, Apoer2. Moreover, NHE6 inhibition restores the Reelin-mediated modulation of excitatory synapses that is impaired by ApoE4. Our findings suggest a novel potential approach for the prevention of late-onset AD.
Physiological constraint on acrobatic courtship behavior underlies rapid sympatric speciation in bearded manakins
Authors: Miles Meredith C , Goller Franz , Fuxjager Matthew J
Published: October 2018

Physiology’s role in speciation is poorly understood. Motor systems, for example, are widely thought to shape this process because they can potentiate or constrain the evolution of key traits that help mediate speciation. Previously, we found that Neotropical manakin birds have evolved one of the fastest limb muscles on record to support innovations in acrobatic courtship display (Fuxjager et al., 2016a). Here, we show how this modification played an instrumental role in the sympatric speciation of a manakin genus, illustrating that muscle specializations fostered divergence in courtship display speed, which may generate assortative mating. However, innovations in contraction-relaxation cycling kinetics that underlie rapid muscle performance are also punctuated by a severe speed-endurance trade-off, blocking further exaggeration of display speed. Sexual selection therefore potentiated phenotypic displacement in a trait critical to mate choice, all during an extraordinarily fast species radiation—and in doing so, pushed muscle performance to a new boundary altogether.
From the cage to the wild: introductions of Psittaciformes to Puerto Rico
Authors: Falcón Wilfredo , Tremblay Raymond L.
Published: October 2018

Introduced psittacine birds can become highly invasive. In this study, we assessed invasions of Psittaciformes in Puerto Rico. We reviewed the literature, public databases, citizen science records, and performed in situ population surveys across the island to determine the historical and current status and distribution of psittacine species. We used count data fromEbirdto determine population trends. For species whose populations were increasing, we modelled their potential distribution using niche modeling techniques. We found 46 Psittaciformes in Puerto Rico, of which 26% are only present as pets, at least 29 species have been reported in the wild, and of those, there is evidence that at least 12 species are breeding. Our results indicate that most introduced species which have been detected as established still persist, although mostly in localized areas and small populations. Clear evidence of invasiveness was found forBrotogeris versicolurusandMyiopsitta monachus, which have greatly expanded their range in recent years.Psittacara erythrogenysandEupsittacula canicularisalso showed population increases, although to a lesser degree. The niche models predicted suitable areas for the four species, and also indicate the potential for range expansion. We discuss the factors leading to invasion success, assess the potential impacts, and we discuss possible management strategies and research prospects.
Effectiveness of telephone-based interventions for managing osteoarthritis and spinal pain: a systematic review and meta-analysis
Authors: O’Brien Kate M. , Hodder Rebecca K. , Wiggers John , Williams Amanda , Campbell Elizabeth , Wolfenden Luke , Yoong Sze Lin , Tzelepis Flora , Kamper Steven J. , Williams Christopher M.
Published: October 2018

Background

Osteoarthritis and spinal pain are common and burdensome conditions; however, the majority of patients with these conditions do not receive care that is consistent with clinical practice guidelines. Telehealth models of care have the potential to improve care for osteoarthritis and spinal pain patients. The aim of this review was to assess the effectiveness of verbal real-time telehealth interventions, including telephone-based and videoconferencing interventions to reduce pain intensity and disability in patients with osteoarthritis of the knee or hip and spinal pain (back or neck pain).

Methods

We searched seven electronic databases from inception to May 2018. Randomised controlled trials (RCTs), cluster-RCTs, and non-randomised controlled trials were included. Two review authors independently extracted data for each included study. Primary outcomes were pain intensity and disability. We conducted primary meta-analyses combining all conditions with similar interventions and comparators. Standardised mean difference (SMD) and 95% confidence intervals (CIs) were calculated using random effects models. We used the Cochrane Risk of Bias tool to assess risk of bias, and GRADE to evaluate the quality of evidence.

Results

We included 23 studies with 56 trial arms and 4,994 participants. All studies utilised telephone-based interventions. Only two studies used a telephone only approach and the remainder included educational materials and/or face-to-face components. We found no studies utilising videoconferencing. Meta-analysis showed telephone-based interventions (with educational materials) for osteoarthritis and spinal pain improved pain intensity (n = 5 trials, n = 1,357 participants, SMD −0.27, 95% CI [−0.53, −0.01], Tau2 = 0.06, I2 = 74%; moderate-quality evidence) and disability (n = 7 trials, n = 1,537 participants, SMD −0.21, 95% CI [−0.40, −0.02], Tau2 = 0.03, I2 = 56%; moderate-quality evidence) compared to usual care. Meta-analyses found telephone with face-to-face interventions does not improve pain and disability compared to usual care or face-to-face care alone.

Discussion

We are moderately confident that telephone-based interventions reduce pain intensity and disability in patients with osteoarthritis and spinal pain compared to usual care, but telephone plus face-to-face interventions are no more effective than usual care or face-to-face interventions alone.
Mitochondrial portrait of the Cabo Verde archipelago: the Senegambian outpost of Atlantic slave trade
Authors: BREHM A. , PEREIRA L. , BANDELT H.‐J. , PRATA M. J. , AMORIM A.
Published: July 2002

In order to study the matrilineal genetic composition in Cabo Verde (Republic of Cape Verde), an archipelago that used to serve as a Portuguese entrepôt of the Atlantic slave trade, we have analysed a total of 292 mtDNAs sampled from the seven inhabitated islands for the hypervariable segment I (HVS‐I) and some characteristic RFLPs of the coding regions. The different settlement history of the northwestern group of the islands is well reflected in the mtDNA pool. The total Cabo Verde sample clearly displays the characteristic mitochondrial features of the Atlantic fringe of western Africa and testifies to almost no mitochondrial input from the Portuguese colonizers.
Neither Hegemony nor Dominance: Reconsidering German Power in Post Cold-War Europe
Authors: SPERLING JAMES
Published: July 2002

German unification in 1989 raised the spectre of German hegemony in post-cold war Europe. In this article, I demonstrate that Germany lacks the structural power consistent with European hegemony or dominance; that there is little evidence supporting an appreciable gap between Germany's structural power and foreign policy ambitions; and that apparent symptoms of German hegemony, particularly the process of institutional emulation in Central and Eastern Europe, reflect other international processes and incentives emanating from the state system itself. This reassessment and downgrading of Germany's relative and absolute power resolve the paradox of German structural power and German reluctance identified by others. But this alternative narrative raises another more important question: why is Germany treated as a potential or even aspiring hegemon in Europe? The answer to that question is located in the interconnected legacies of Auschwitz and the occupation regime. This joint legacy constitutes an important part of the historical context within which we frame our assessments and judgements of German power; explains the frequently unwarranted exaggeration and suspicion of German power; and demonstrates how the past can function as a powerful prism though which we interpret the intentions, ambitions and capabilities of a state.
Individual Rights and Social Movements: A Comparative and Statistical Inquiry
Authors: FOWERAKER JOE , LANDMAN TODD
Published: July 2002

This article is a comparative study of the relationship between social movements and the individual rights of citizenship. It identifies three main connections between collective action and individual rights made in theory and history, and analyses them in the context of modern authoritarian regimes. It does so by measuring both social mobilization and the presence of rights over time in Brazil, Chile, Mexico and Spain, and analyses their mutual impact statistically – both within and across these national cases. The results demonstrate the mutual impact between rights and movements, and more importantly, constitute a robust defence of democracy as the direct result of collective struggles for individual rights.
The Shaping of Popular Satisfaction with Government and Regime Performance in Germany
Authors: CUSACK THOMAS R.
Published: July 2002

The article focuses on citizens’ satisfaction with the German democratic political system. The empirical analysis reported supports the argument that the performance of the economy and the government affect popular satisfaction with the regime. In the East, satisfaction with the regime remains very low and dissatisfaction has spread into West Germany. In the West, the sources of this dissatisfaction are both economic developments and government performance; citizens modify their views on the system as a consequence of the government’s and the economy’s successes and failures. The dynamic is similar in the East. Economic strains, and the perception that the federal government is not making sufficient efforts to equalize living standards, have kept the Eastern population from committing themselves to the new unified political system.
A Comment on Browne and Patterson’s ‘An Empirical Theory of Rational Nominating Behaviour Applied to Japanese District Elections’
Authors: COX GARY W.
Published: July 2002

In this Note, I comment briefly on Browne and Patterson's interesting article on rational nominating behaviour in Japan. Their empirical results appear sound. Where I differ is mostly in how to interpret them.

Browne and Patterson frame their article as providing ‘a critical empirical test of the proposition that the nominating behaviour of Japanese parties is based on rational calculation’. Presumably Browne and Patterson did not mean to claim that they were testing the rationality assumption, as such a thing would be problematic from the usual Lakatosian view of social science. Instead, what they are really aiming at are previous studies that either directly impugn the ability of Japanese nominators to deduce and implement optimal seat-maximizing solutions to the nomination problems posed by Japan's former electoral system or that report ‘error rates’ that appear to them to call into question whether the nominators' main goal really could have been seat maximization.
AN EQUIVARIANT WHITEHEAD ALGORITHM AND CONJUGACY FOR ROOTS OF DEHN TWIST AUTOMORPHISMS
Authors: Krstić Sava , Lustig Martin , Vogtmann Karen
Published: July 2002

Given finite sets of cyclic words $\{u_1,\dots,u_k\}$ and $\{v_1,\dots,v_k\}$ in a finitely generated free group $F$ and two finite groups $A$ and $B$ of outer automorphisms of $F$, we produce an algorithm to decide whether there is an automorphism which conjugates $A$ to $B$ and takes $u_i$ to $v_i$ for each $i$. If $A$ and $B$ are trivial, this is the classic algorithm due to Whitehead. We use this algorithm together with Cohen and Lustig’s solution to the conjugacy problem for Dehn twist automorphisms of $F$ to solve the conjugacy problem for outer automorphisms which have a power which is a Dehn twist. This settles the conjugacy problem for all automorphisms of $F$ which have linear growth.

AMS 2000 Mathematics subject classification: Primary 20F32. Secondary 57M07
Responses of Irish potatoes (Solanum tuberosum L.) to mineral and
organic fertilizer in various agro-ecological environments in Kenya
Authors: Recke H. , Schnier H. F. , Nabwile S. , Qureshi J. N.
Published: July 2002

The response of potatoes (Solanum tuberosum L.) to application of inorganic and organic fertilizer was studied in long-term field experiments between 1987 and 1994. Responses to phosphorus and nitrogen were tested at 27 sites and to potassium at 17 sites. The sites represented various agro-ecological zones in Kenya. Phosphate (triple superphosphate, TSP) and nitrogen (calcium ammonium nitrate, CAN) fertilizer were applied at 0, 25, 50 or 75 kg P2O5 ha−1 and 0, 25, 50 or 75
kg N ha−1. Potassium (muriate of potash) was tested mainly
on sites with low levels of K in the soil at rates of 0 or 50 kg K2O ha−1. Farmyard manure was applied at 0 or 5 t ha−1 with or without N and/or P2O5 fertilizer.

Over the study period average yields varied considerably between sites and agro-ecological zones. At 16 of the 27 sites, potatoes responded strongly to the application of P2O5 and at 9 sites to N application. A significant response to K2O application was found at three out of the 17 sites. Nutrient use efficiency ranged from 13 to 214 kg tubers per kg P2O5 and from 20 to 113 kg tubers per kg N applied. In the majority of the sites, both N and P response followed a linear function which suggests that application rates higher than 75 kg N ha−1 and/or 75 kg P2O5 ha−1 could be beneficial. Economic analysis revealed that in most cases fertilizer application was highly profitable for potatoes.

The critical soil P value was about 15 ppm (mod. Olsen) for optimal potato nutrition; on soils with higher P levels generally no P response was found. The respectively critical soil K value was found to be about 0.55 meq 100 g−1 (modified Olsen). Farmyard manure at 5 t ha−1 significantly increased yields of potatoes at 9 of the 27 sites. On soils with P levels below 12 ppm, there was a positive effect on potato yields with a combination of 50 kg P2O5 ha−1 and farmyard manure, although significant differences were achieved in only one out of the 19 sites.
COMPARISON OF SINGLE CROPPING, RELAY CROPPING AND DOUBLE CROPPING OF SOYABEANS WITH WHEAT USING CULTIVAR BLENDS
Authors: JACQUES S. , BACON R. K. , PARSCH L. D.
Published: July 2002

Comparisons of single cropping, double cropping and relay cropping of soyabeans (Glycine max) with wheat (Triticum aestivum) were made at two sites in Arkansas over a two-year period. The comparisons were made using both soyabean blends and their component cultivars. In relay cropping the yields of pure lines of soyabeans were reduced by 17% compared with single-cropped soyabeans, but the yield of wheat in relay cropping was 15% less than in double cropping. Double cropping reduced the branch number, plant height, node number and leaf area of soyabeans compared with single cropping, but relay cropping reduced only node number and leaf area. Both double cropping and relay cropping gave greater land equivalent ratio (LER) values than single cropping, and double cropping gave greater LER values than relay cropping. Net returns were lowest with single cropping and greatest with double cropping. Soyabean blends gave yields similar to the mean of the component genotypes in all three cropping systems, and the net returns of blends were similar to those of the means of component genotypes.
CUPPA-TEA: A SIMULATION MODEL DESCRIBING SEASONAL YIELD VARIATION AND POTENTIAL PRODUCTION OF TEA. 2. BIOMASS PRODUCTION AND WATER USE
Authors: MATTHEWS R. B. , STEPHENS W.
Published: July 2002

A model predicting biomass production and water use in tea plantations is described. Biomass production is calculated from the amount of light intercepted and a radiation conversion efficiency. Available assimilate (current production plus reserves) is distributed according to the ‘potential’ demand of each of the shoots, stems and roots. Any excess is stored in the stem and root reserve pool. In the case of the demand for assimilate exceeding the supply, allocation is according to the relative demands of each component. Simulations with the model suggest that assimilate supply is unlikely to limit shoot growth under most conditions. Soil water movement and crop water uptake are simulated using the water balance sub-model used by the CERES crop growth models. The model calculates a water stress factor (Φ) as the ratio of actual to potential crop transpiration, and uses this factor to adjust various crop processes such as dry matter production and shoot development and extension rates. Predicted yields match observed yields well across a range of watering treatments and for different years at sites in Tanzania and Zimbabwe, providing some degree of confidence in the model's ability to predict tea yields for environments in East Africa.
Detection and localization of a single binary trait locus in experimental populations
Authors: McINTYRE LAUREN M. , COFFMAN CYNTHIA J. , DOERGE R. W.
Published: July 2002

The advancements made in molecular technology coupled with statistical methodology have led to the successful detection and location of genomic regions (quantitative trait loci; QTL) associated with quantitative traits. Binary traits (e.g. susceptibility/resistance), while not quantitative in nature, are equally important for the purpose of detecting and locating significant associations with genomic regions. Existing interval regression methods used in binary trait analysis are adapted from quantitative trait analysis and the tests for regression coefficients are tests of effect, not detection. Additionally, estimates of recombination that fail to take into account varying penetrance perform poorly when penetrance is incomplete. In this work a complete probability model for binary trait data is developed allowing for unbiased estimation of both penetrance and recombination between a genetic marker locus and a binary trait locus for backcross and F2 experimental designs. The regression model is reparameterized allowing for tests of detection. Extensive simulations were conducted to assess the performance of estimation and testing in the proposed parameterization. The proposed parameterization was compared with interval regression via simulation. The results indicate that our parameterization shows equivalent estimation capabilities, requires less computational effort and works well with only a single marker.
Colonization with long-distance seed dispersal and genetic

structure of maternally inherited genes in forest trees: a

simulation study
Authors: LE CORRE VALÉRIE , MACHON NATHALIE , PETIT RÉMY J. , KREMER ANTOINE
Published: July 2002

Since the last glacial period forest trees have expanded to their

present range very rapidly, with rates up to 500 m yr−1

for oaks in Europe, which can be explained only by the dispersion of acorns

over long distances. We used a stratified dispersal model, including both

diffusive and long-distance dispersal of seeds, to simulate the colonization

of a 100 km×300 km grid by populations

of oak trees. An appropriate rate of spread is obtained with rare

dispersal at distances of the order

of tens of kilometres. We simulated the effect of stratified versus

diffusive dispersal of seeds on the

spatial genetic structure at a maternally inherited locus. Founding

events associated with stratified

dispersal generate a high amount of genetic differentiation among

populations, which is likely to

persist for a long time after colonization. Using autocorrelation methods,

we show that diffusive

and stratified dispersals create quite different spatial patterns of

variation for the maternally

inherited locus. Stratified dispersal creates patchy patterns that are

concordant with a previous

experimental investigation of chloroplast DNA variation at a

regional scale in the oaks Quercus

petraea and Quercus robur. For plant populations that

have passed through recent episodes of

range expansion, long-distance dispersal events are probably the most

important factors of spatial

genetic structuring of maternally inherited genes at small or medium

geographic scales.
Dynamics of recombination modifiers caused by cyclical
selection: Interaction of forced and auto-oscillations
Authors: KOROL A. B. , KIRZHNER V. M. , NEVO E.
Published: July 2002

Temporally varying selection is considered to be one of the potential
mechanisms of recombination
evolution. We found earlier that simple cyclical selection for a trait
controlled by multiple additive,
dominant or semi-dominant loci can result in extremely complex limiting
behaviour (CLB) of
population trajectories, including ‘supercycles’ and more complex
attractors. Recombination rate
proved to be a key factor affecting the mode of CLB and the very existence
of CLB. Therefore, we
considered here a generalized model: the fixed recombination rate was replaced
by a polymorphic
recombination modifier. The modifier-dependent changes included: (a) supercyclical
dynamics due
to the recombination modifier in a system that does not manifest CLB when
recombination rate is
a fixed parameter; (b) appearance of a new level of superoscillations (super-supercycles)
in a
system that manifests supercycles with a fixed modifier; (c) chaotization
of the regular supercyclical
dynamics. The domain of attraction of these movements appeared to be quite
large. It is
noteworthy that the modifier locus is an active participant in the observed
non-monotonic limiting
movements. Interactions between short-period forced oscillations and the
revealed long-period
auto-oscillations appeared to result in new regimes of recombination evolution
(for some range of
linkage between the modifier locus and the selected system), as compared
with those caused by the
forced oscillations alone.
Speed congenics: accelerated genome recovery using genetic
markers
Authors: VISSCHER P. M.
Published: July 2002

Genetic markers throughout the genome can be used to speed up ‘recovery’ of the recipient
genome in the backcrossing phase of the construction of a congenic strain. The prediction of the
genomic proportion during backcrossing depends on the assumptions regarding the distribution of
chromosome segments, the population structure, the marker spacing and the selection strategy. In
this study simulation was used to investigate the rate of recovery of the recipient genome for a
mouse, Drosophila and Arabidopsis genome. It was shown that an incorrect assumption of a
binomial distribution of chromosome segments, and failing to take account of a reduction in
variance in genomic proportion due to selection, can lead to a downward bias of up to two
generations in the estimation of the number of generations required for the formation of a
congenic strain.
Estimating the genetic architecture of quantitative traits
Authors: ZENG ZHAO-BANG , KAO CHEN-HUNG , BASTEN CHRISTOPHER J.
Published: July 2002

Understanding and estimating the structure and parameters associated with the genetic architecture
of quantitative traits is a major research focus in quantitative genetics. With the availability of a
well-saturated genetic map of molecular markers, it is possible to identify a major part of the
structure of the genetic architecture of quantitative traits and to estimate the associated
parameters. Multiple interval mapping, which was recently proposed for simultaneously mapping
multiple quantitative trait loci (QTL), is well suited to the identification and estimation of the
genetic architecture parameters, including the number, genomic positions, effects and interactions
of significant QTL and their contribution to the genetic variance. With multiple traits and multiple
environments involved in a QTL mapping experiment, pleiotropic effects and QTL by environment
interactions can also be estimated. We review the method and discuss issues associated with
multiple interval mapping, such as likelihood analysis, model selection, stopping rules and
parameter estimation. The potential power and advantages of the method for mapping multiple
QTL and estimating the genetic architecture are discussed. We also point out potential problems
and difficulties in resolving the details of the genetic architecture as well as other areas that require
further investigation. One application of the analysis is to improve genome-wide marker-assisted
selection, particularly when the information about epistasis is used for selection with mating.
The effect of epistasis on the structure of hybrid zones
Authors: BARTON N. H. , SHPAK M.
Published: July 2002

Within hybrid zones that are maintained by a balance between selection and dispersal, linkage
disequilibrium is generated by the mixing of divergent populations. This linkage disequilibrium
causes selection on each locus to act on all other loci, thereby steepening clines, and generating a
barrier to gene flow. Diffusion models predict simple relations between the strength of linkage
disequilibrium and the dispersal rate, σ, and between the barrier to gene flow, B, and the reduction
in mean fitness, W¯. The aim of this paper is to test the accuracy of these predictions by
comparison with an exact deterministic model of unlinked loci (r = 0·5). Disruptive selection acts
on the proportion of alleles from the parental populations (p,
q): W = exp[−S(4 pq)β],
such that the least fit genotype has fitness e−S. Where
β [Lt ] 1, fitness is reduced for a wide range of intermediate genotypes; where
β [Gt ] 1, fitness is only reduced for those genotypes close to p = 0·5.
Even with strong epistasis, linkage disequilibria are close to
σ2p′ip′j/
rij, where p′i,
p′j are the gradients in allele frequency at loci
i, j. The barrier to gene flow, which is reflected in the
steepening of neutral clines, is given by

formula here

where r¯, the harmonic mean recombination rate between the neural and selected loci, is here 0·5.
This is a close approximation for weak selection, but underestimates B for strong selection. The
barrier is stronger for small β, because hybrid fitness is then reduced over a wider range of p. The
widths of the selected clines are harder to predict: though simple approximations are accurate for
β = 1, they become inaccurate for extreme β because, then, fitness changes sharply with p.
Estimates of gene number, made from neutral clines on the assumption that selection acts against
heterozygotes, are accurate for weak selection when β = 1; however, for strong selection, gene
number is overestimated. For β > 1, gene number is systematically overestimated and, conversely,
when β < 1, it is underestimated.
Rates of movement of transposable elements on the second
chromosome of Drosophila melanogaster
Authors: MASIDE XULIO , ASSIMACOPOULOS STAVROULA , CHARLESWORTH BRIAN
Published: July 2002

The rates of movement of 11 families of transposable elements of Drosophila melanogaster were
studied by means of in situ hybridization of probes to polytene chromosomes of larvae from a
long-term mutation accumulation experiment. Replicate mutation-accumulation lines carrying
second chromosomes derived from a single common ancestral chromosome were maintained by
backcrosses of single males heterozygous for a balancer chromosome and a wild-type chromosome,
and were scored after 116 generations. Twenty-seven transpositions and 1 excision were detected
using homozygous viable and fertile second chromosomes, for a total of 235056 potential sources
of transposition events and a potential 252880 excision events. The overall transposition rate per
element per generation was 1·15×10−4 and the excision rate
was 3·95×10−6. The single excision (of
a roo element) was due to recombination between the element's long terminal repeats. A survey of
the five most active elements among nine homozygous lethal lines revealed no significant difference
in the estimates of transposition and excision rates from those from viable lines. The excess of
transposition over excision events is in agreement with the results of other in situ hybridization
experiments, and supports the conclusion that replicative increase in transposable element copy
number is opposed by selection. These conclusions are compared with those from other studies,
and with the conclusions from population surveys of element frequencies.
REGULATING NORTHERN IRELAND:
THE SPECIAL POWERS ACTS,
1922–1972
Authors: DONOHUE LAURA K.
Published: July 2002

Although the 1922–43 Special Powers Acts (SPAs) played a
central role in prompting
the Northern Irish civil rights movement in the late 1960s, virtually no
secondary literature exists on
the operation of the statutes. This article examines the manner in which
the unionist government
employed the acts during the tenure of the northern parliament. It suggests
that the 1922–43 SPAs
became a central grievance of the minority community because of the manner
in which regulations
introduced under their auspices were exercised: the ministry of home affairs
initially used the emergency
statutes to return civil order to the province; however, as violence declined
the government began to
utilize regulations to prevent the expression of republican ideals. Any
attempt to garner support for a
united Ireland was perceived as an attack on the Northern Irish constitution.
Concurrent with this shift
was a change in justification for the 1922–43 SPAs: from being required
in order to establish law and
order in the face of rising violence, they were soon heralded by unionists
as necessary to maintain the
constitutional structure of the North. In preventing the public exposition
of republicanism, expressions
of nationalism were likewise limited. This impacted upon a large portion
of the minority community,
giving rise to claims that the statutes were being unfairly applied.
MICHAL BIRAN, Qaidu and the Rise of the Independent Mongol State in Central Asia (Richmond, Surrey, U.K.: Curzon, 1997). Pp. 208. $75.00 cloth.
Authors: Tucker Ernest
Published: July 2002

Michal Biran fills an important gap in research on the 13th-century Mongol empire with her recent study of Qaidu (1236–1301), a great-grandson of Chinggis Khan and champion of the house of Ögödei. Characterizing Qaidu as a pragmatist, not an “ideological warrior” (p. 107), she challenges the conventional view that he was one of the quintessential defenders of nomadic values against the sedentarizing ethos of other Mongol rulers, and that he claimed the office of qa⊂an (supreme Mongol overlord). The work argues that his long struggle with Qubilai and his ruling career in Central Asia had two main goals: to restore to the Ögödeid ulus its rightful territory according to the original division of the empire by Chinggis and to secure the political and economic viability of that territory. It concludes that Qaidu did not aspire to become the qa⊂an but played a crucial role in the emergence of an independent Chaghadaid khanate in the early 14th century.
Influence of xylanase-supplemented feed on the
development of selected bacterial groups in the
intestinal tract of broiler chicks
Authors: VAHJEN W. , GLÄSER K. , SCHÄFER K. , SIMON O.
Published: July 2002

The colonization of Lactobacillus spp., enterobacteria

and facultatively anaerobic gram-positive cocci
was monitored in intestinal samples of growing broiler chicks from
24 h to 28 days of age. Rapid
bacterial growth occurred within the first week, followed by
stabilization and decline of colony
forming units (CFU). Xylanase supplementation led to significantly lower
CFU per gram of wet
weight for total presumptive enterobacteria and total gram-positive cocci
in luminal and tissue
samples in the first 3 weeks. Lactobacillus spp. colony
counts from tissue samples were higher for
animals with the xylanase-supplemented diet, but luminal CFU were not.
The composition of
dominant Lactobacillus spp. strains was different in duodenal

and jejunal tissues, but distribution of
Lactobacillus spp. colony forms was unaffected by xylanase
treatment. Mucosa-associated
Enterococcus spp. displaced the dominant gram-positive cocci in

the jejunal samples. d- and l-lactic
acid and acetic acid concentrations were significantly higher in
ileal samples from the control group
on days 7 and 14, while butyric acid concentrations were higher
in the xylanase-treated group. It is
concluded that the less viscous intestinal environment caused by
the xylanase slowed proliferation
of gram-positive cocci and presumptive enterobacteria in
enzyme-supplemented animals in the first 3 weeks of life.
MOSQUITO AVOIDANCE AND BED NET USE IN THE GREATER ACCRA REGION, GHANA
Authors: AGYEPONG IRENE AKUA , MANDERSON LENORE
Published: July 2002

Qualitative research and cross-sectional survey methods were used in a study conducted in rural and urban areas of the Greater Accra Region, Ghana, to explore people's understanding of the cause of malaria and patterns of mosquito avoidance, in particular bed net ownership and use. The study indicated far higher bed net ownership and use in rural than urban areas, which was related partly to perceived affordability and partly to the different contexts of and reasons for avoiding mosquitoes. Knowledge of an association between mosquitoes and malaria, the most common cause of illness in both areas, was related to residence but not to literacy or formal education, and this knowledge did not predict bed net use. The paper points to the complexity of social and personal factors implicated in behavioural interventions for malaria control, and questions behavioural models that assume a linear relationship between knowledge and practice.
Odour-impact compounds of Gorgonzola cheese
Authors: MOIO LUIGI , PIOMBINO PAOLA , ADDEO FRANCESCO
Published: July 2002

Volatile concentrates were obtained by vacuum distillation from both
natural and creamy Gorgonzola cheese and isolated by continuous liquid–liquid
extraction. Both were analysed by high resolution gas chromatography (HRGC),
HRGC–mass spectrometry and HRGC–olfactometry. A total of 63 components were
identified in the neutral extract of the natural type (21 esters, 13 ketones, 14 alcohols,
5 aldehydes, 1 sulphur compound, 7 aromatic compounds and 2 terpenes) and 52
in the creamy type (17 esters, 12 ketones, 10 alcohols, 5 aldehydes, 1 sulphur
compound, 5 aromatic compounds and 2 terpenes). Ketones, whose major
components were 2-nonanone and 2-heptanone, were the predominant constituents
of the neutral fraction. By olfactometric analysis of the neutral extracts, 23 odour-impact compounds were found in the natural and 21 in the creamy Gorgonzola
cheese. 1-Octen-3-ol, ethyl hexanoate, 2-nonanone, 2-heptanone, 2-heptanol, ethyl
butanoate, 2-nonanol and 4-methylanisole were the key odorants of the natural
cheese, whereas 2-heptanone, 2-heptanol, ethyl butanoate, 3-methyl thiopropanal
and an unidentified constituent with a fruity odour were characteristic of the creamy
Gorgonzola cheese. On the basis of high odour unity values, 2-nonanone, 1-octen-3-ol, 2-heptanol, ethyl hexanoate, methylanisole and 2-heptanone were the most
important odorants of natural and creamy Gorgonzola cheese aroma.
Determination of taste-active compounds of a bitter Camembert cheese by omission tests
Authors: ENGEL ERWAN , SEPTIER CHANTAL , LECONTE NADINE , SALLES CHRISTIAN , LE QUERE JEAN-LUC
Published: July 2002

The taste-active compounds of a Camembert cheese selected for its intense bitterness defect were investigated. The water-soluble fraction (WSE) was extracted with pure water and fractionated by successive tangential ultrafiltrations and nanofiltration. The physicochemical assessment of these fractions led to the construction of a model WSE which was compared by sensory evaluation to the crude water-soluble extract, using a panel of 16 trained tasters. As no significant difference was perceived, this model WSE was then used directly or mixed with other cheese components for omission tests. Among the main taste characteristics of the WSE (salty, sour, umami and bitter), bitterness was found to be due to small peptides whose mass distribution was obtained by RPHPLC-MS (400–3000 Da) and whose taste properties are discussed.
Effect of yogurt and bifidus yogurt fortified with skim milk powder,
condensed whey and lactose-hydrolysed condensed whey on serum
cholesterol and triacylglycerol levels in rats
Authors: BEENA ATHRAYILKKALATHIL , PRASAD VELORE
Published: July 2002

The possible hypocholesterolaemic properties of milk and fermented milk
products have been investigated in groups of albino rats given a
basal diet, basal diet
plus cholesterol, and basal diet plus cholesterol together with
whole milk or standard
or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey
or lactose-hydrolysed condensed whey. After 30 d,
triacylglycerols, total cholesterol,
HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and
ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing
lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol.
In general, yogurts changed HDL-cholesterol little, but tended to raise
triacylglycerols. There was marked lowering of LDL-cholesterol
in rats given either type of
yogurt fortified with whey proteins. This study has demonstrated in a rat model that
bifidus yogurts and yogurts fortified with whey proteins can reduce total and
LDL-cholesterol, and suggests that if they have the same effect
in human subjects they
have potential value in cholesterol-lowering diets.
Growth factors in milk: interrelationships with
somatic cell count
Authors: LIEBE ANDREA , SCHAMS DIETER
Published: July 2002

Growth factors are thought to play a decisive role
in the course of
inflammatory processes. The aim of the present study was
to characterize a potential
interrelationship between the concentrations of
insulin-like growth factor-1 (IGF-1),
basic fibroblast growth factor (bFGF) and somatic cell
count (SCC) in normal milk,
and to investigate the presence of these growth factors
in mammary secretions of
cows suffering from clinical and subclinical mastitis.
Quarter secretions of cows with
spontaneous acute clinical mastitis and of cows with
subclinical mastitis were
analysed radioimmunologically for their concentrations of
IGF-1 and bFGF. During
two relocation trials with normally lactating Brown
Swiss cows, dramatic changes in
milk somatic cell count were obtained following a short-term
change (5 d) of location
and housing system. The animals were relocated from
their familiar loose housing
system with concrete slatted floor to a separate stanchion
barn with long stalls and
straw bedding, and vice versa. The concentration
profile of IGF-1, but not of bFGF,
corresponded well with SCC during the relocation trials,
the positive correlation
between the characteristics being highly significant, as
determined by regression
analysis (r=0·60; P<0·001).
The results provide evidence that significant changes
in SCC and growth factor content may be caused by
environmental factors other
than infection. The concentrations of both IGF-1 and bFGF
were greatly elevated in
secretions of quarters affected by acute clinical
mastitis compared with the
corresponding clinically healthy quarters. Subclinically
affected quarters with high
SCC, as compared with non-affected quarters with low SCC,
also had elevated milk
IGF-1, but unchanged bFGF. Measuring of growth factor
profiles in milk may have
value in the near future in monitoring the state of udder
health in addition to SCC.
Identification of C-terminally truncated forms of β-lactoglobulin
in
whey from Romagnola cows' milk by two dimensional
electrophoresis coupled to mass spectrometry
Authors: ZAPPACOSTA FRANCESCA , DI LUCCIA ALDO , LEDDA LUIGI , ADDEO FRANCESCO
Published: July 2002

Four minor protein components were detected in whey from Romagnola

cows' milk by polyacrylamide gel isoelectric focusing and two dimensional
gel
electrophoresis. Individual protein spots were transferred by electroblotting
on to a
polyvinylidene difluoride membrane and isolated by cutting out the relevant
area.
After in situ trypsinolysis, a portion of the digest was analysed
directly by
matrix-assisted laser desorption ionization–time of flight mass spectrometry.
The mass
profile allowed us to establish a correlation between β-lactoglobulins
A and B and the
four minor whey protein components. They were identified as C-terminally
truncated
β-lactoglobulin A and B variants with missing N-terminal peptides,
beyond residues
in the range 100–123 and 136–147 respectively. Two of the minor
components were
related to β-lactoglobulin A and two to β-lactoglobulin B.