High Level Of Variation Research Articles

An Investigation of Coat Colour Distribution of West African Dwarf Goats

This study was carried out to determine coat colour distribution of West African Dwarf (WAD) goat in Abeokuta North and South Local Government Areas of Ogun State, Nigeria. Three thousand, three hundred and ten (3310) WAD goats were randomly sampled consisting of 2511 (75.86%) does and 799 (24.14%) bucks. Animals were prevalently maintained on semi-intensive management. Various coat colours identified were black with highest frequency of 941 (28.42%), brown 436 (13.17%), badgerface 346 (10.45%), grey 254 (7.67%), buckskin 222 (6.70%), lateral belly 154 (4.65%), white and black 149 (4.50%), white and brown 134 (4.05%), white and black marking 105 (3.17%), black and white marking 92 (2.78%), spotted white 88 (2.66%), spotted black 80 (2.42%), blackmash 63 (1.90%), tan 61 (1.84%), white 57 (1.72%), bezoar 49 (1.48%), spotted brown 40 (1.21%), lateral stripes 33 (1.00%), with swiss marking having the lowest frequency of 6 (0.18%). The gene frequency was estimated using Hardy-Weinberg equilibrium equation which resulted as 0.70 and 0.30 for eumelanin and Phaeomelanin respectively. Chi-square (χ2) analysis was further carried out, which revealed that the difference between observed frequency and expected frequency was significant (P < 0.05) implying that the segregation in the area of study was not supported by Mendelian ratio of 3:1. High level of variation was observed in coat colour among goats in the areas studied with black coat colour being the predominant. Hence, conscious selection could be embarked upon to investigate the influence of coat colour on adaptation, thermoregulation, growth and productivity.

Abstract TP386: Growing Intracranial Aneurysms in Older Patients Tend to Have Higher Annual Growth Rates

Introduction: Numerous previous studies have discussed the correlation between patient age and aneurysm rupture. However, the existing base of knowledge regarding the relationship between patient age and aneurysm growth, specifically growth rate, is significantly smaller. The objective of this study is to examine the correlation between patient age and aneurysm growth in order to help devise better clinical management strategies. Hypothesis: Growing aneurysms in older patients will exhibit a higher mean growth rate relative to those in younger patients. Methods: In this study, the records of 361 patients between the age of 40 and 97 at the time of initial diagnosis with unruptured intracranial aneurysms in the UCLA Medical Center between January 2005 and December 2015 were reviewed. These patients were continuously followed using CTA neurovascular imaging, ending when the patient either received surgical or endovascular treatment or discontinued follow-up visits. Results: A total of 496 UIA in the 361 patients were classified into four groups by patient age (40-49, n=56; 50-59, n=120; 60-69, n=145; 70+, n=175). Incidence of growth was 14.29%, 11.67%, 8.28%, and 12.57% for the 40-49, 50-59, 60-69, and 70+ groups, respectively. Growth rates were 0.30±0.12, 0.58±0.42, 0.90±0.72, and 0.78±0.75 mm/yr for the 40-49, 50-59, 60-69, and 70+ groups, respectively. Differences in growth rates were not significant between the four groups (ANOVA, p=0.15). However, when patients were divided by age 50 years, growth rates were significantly higher in the 50+ group (p<0.05). Conclusion: Although there was a high level of variation in growth rate between individual cases, this study found that patients with growing aneurysms over the age of 50 are at a higher risk for rapid aneurysm growth compared to younger patients, a finding that may prove helpful in developing clinical management protocols.

How do social security expenditures vary by state? The surprising impact of unemployment

AbstractWe examine state-level variation in the flow of benefits under the largest Social Security programme – the Old-Age (OA) programme. OA pensions remain a robust and growing component of the American social safety net. Although OA pensions are entirely administered by the federal government, state-level demographic features can imply different aggregate levels of programme expenditures across states. We describe high levels of variation in the resources flowing into states from the OA programme and we find relationships between state features that might seem only remotely related to income support for the elderly: current unemployment rates, previous income levels, poverty rates and minority populations. We find a particularly strong link between current unemployment rates, OA coverage and OA average benefits. The number of recipients and the level of average OA payments increase when unemployment increases. This is a poorly understood but important feature of the OA programme.

Methanogenic fermentation of lignite with carbon-bearing additives, inferred from stable carbon and hydrogen isotopes

Lignite from the Konin area (Poland) was used as a substrate for incubation experiments to evaluate its potential for simulation of biogenic methane production. Lignite was incubated with a bacterial inoculum enriched from lake sediments, mineral media, and various supplemental components for microbial life. Additives, such as acetate, methanol, glucose, nutrient broth, and yeast extract, can significantly increase methane production. At the same time, biodegradation of these additional carbon sources leads to overestimation of methane yield. In this paper, selected geochemical properties (total organic carbon content; stable isotopic composition of carbon δ13C) were analyzed in order to evaluate changes in the organic matter of fermented lignite. Stable isotope analysis of carbon and hydrogen was applied in order to identify sources of methane and carbon dioxide formation. TOC decreased in range from 1.4 to 9.6% in lignite after fermentation. The δ13C value of lignite used in the experiments (−25.2‰) decreased after incubation to values in range from −27.1 to −26.2‰. Methane yield per g of TOC (lignite + organic carbon in nutrients) ranged from 0.47 to 2.60mM/g. Glucose, acetate, and methanol significantly increased biogas production. Nutrient broth and yeast extract were not a source of organic carbon for methane formation, but their presence enhanced biogas production. Values of δ13C(CH4) and δ2H(CH4) across incubation conditions ranged from −70.2 to −24.2‰ and from −396.6 to −290.5‰, respectively. Values of δ13C(CO2) ranged from –55.2 to 45.0‰. The high level of variation of δ13C(CH4) and δ13C(CO2) suggests mixing of gases from different carbon sources during incubation, but can also be caused by mixing of metabolic modes by the microbial community. Understanding the δ2H(CH4) variation is even more difficult than the δ13C(CH4) and δ13C(CO2), since many substrates often contain exchangeable hydrogen (e.g. in water, lignite, and elements of nutrients). The combined values of δ13C(CH4) and δ13C(CO2) suggests that the dominant methanogenesis pathway in our experiments may be acetate fermentation. In biodegraded lignite, high relative concentrations of p-cresol (one of the most abundant in the sample) and n-(2-acetylphenyl)formamide were identified. These compounds are most probably lignin decomposition products, or, in the case of the latter, bacterial by-products or remnants. Organic compounds with low molecular weights, n-alkanes, and biomolecules including ferruginol, sugiol, and 6,7-dehydroferruginol, as well as amyrins and tocopherols, were preferentially degraded. The potential for methane production from lignite spiked with carbon-bearing additives is at least one magnitude lower than that from agricultural wastes. The lignite utilization as the single substrate for methanogenic fermentation is economically unprofitable. Mixing of lignite with the external substrate as biomass may be an alternative for consideration and future research.

Evolutionary relationship of three mitten crabs (Eriocheir sp) revealed by mitogenome and 5S ribosomal DNA analysis

To reveal the evolutionary relationship of three mitten crabs (Eriocheir sinensis, E. hepuensis, and E. japonica), complete mitogenomes and nuclear 5S rDNA sequences were analyzed. Sequencing revealed that the mitogenomes analyzed shared conserved organization of the coding and non-coding regions but genetic variation was identified. Among the three mitten crabs distinct tandem repeats were identified in the mitochondrial D-loop region. The 5S gene (5S rDNA) sequence was highly conserved across the three species, whereas non-transcribed spacer (NTS) region exhibit high levels of variation including insertions, deletions and point mutations. Cluster analysis suggested that the three mitten crabs had their own independent 5S rDNA sequence variation and evolutionary pattern. Both mitogenome and 5S rDNA sequence analysis revealed significant genetic variation across the mitten crabs species. Phylogenetic analysis using mitogenome and 5S rDNA sequences demonstrated that E. japonica was relatively more distant from E. sinensis and E. hepuensis. This study extended our previous knowledge and confirmed that the three mitten crabs are likely to be genetically differentiated species. In addition, our study also provided insights into the conservation of pure natural resources of E. sinensis, an important aquaculture species.

Quantifying biological samples using Linear Poisson Independent Component Analysis for MALDI-ToF mass spectra.

MotivationMatrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI) facilitates the analysis of large organic molecules. However, the complexity of biological samples and MALDI data acquisition leads to high levels of variation, making reliable quantification of samples difficult. We present a new analysis approach that we believe is well-suited to the properties of MALDI mass spectra, based upon an Independent Component Analysis derived for Poisson sampled data. Simple analyses have been limited to studying small numbers of mass peaks, via peak ratios, which is known to be inefficient. Conventional PCA and ICA methods have also been applied, which extract correlations between any number of peaks, but we argue makes inappropriate assumptions regarding data noise, i.e. uniform and Gaussian.ResultsWe provide evidence that the Gaussian assumption is incorrect, motivating the need for our Poisson approach. The method is demonstrated by making proportion measurements from lipid-rich binary mixtures of lamb brain and liver, and also goat and cow milk. These allow our measurements and error predictions to be compared to ground truth.Availability and implementationSoftware is available via the open source image analysis system TINA Vision, www.tina-vision.net.Supplementary information Supplementary data are available at Bioinformatics online.

Acoustic variation in the advertisement call of the Lime treefrog Sphaenorhynchus caramaschii (Anura: Hylidae)

Frog vocalizations are acoustic signals that contain specific recognition information, so detailed descriptions of calls are critical for improved taxonomic understanding and to establish boundaries between species. The study of the variation of acoustic properties, both within and among individuals, contributes to species diagnosis and can provide support for phylogenetic hypotheses. Herein we provide a more thorough description of the vocalizations of Sphaenorhynchus caramaschii, which includes analysis of the variation in call characteristics within and among individuals. We analyzed 305 calls of 14 males from three municipalities (Ribeirão Branco, Iporanga, and Ribeirão Grande) and compared the acoustic properties among these populations. Two types of notes were recognized in the advertisement call: a previously undescribed note with multiple pulses, called “A”, and another note with single pulse, called “B”. The temporal properties of the call were considered dynamic because of a high level of variation, and the spectral properties were considered static (with low variation) among calls from the same individual and those from different individuals. The advertisement call description presented in this paper is very distinct from the previous description, which was based on a single male recorded at Piraquara (140 km from the type-locality). Herein we discuss the implications of the variation in acoustic properties among populations. In addition, we present data on the effect of air temperature on dynamic acoustic properties and calling sites used by the species.

Genetic diversity of bottlenose dolphin (Tursiops sp.) populations in the western North Pacific and the conservation implications

The evolutionary processes that shape patterns of diversity in highly mobile marine species are poorly understood, but important towards transferable inference on their effective conservation. In this study, bottlenose dolphins (Tursiops sp.) are studied to address this broader question. They exhibit remarkable geographical variation for morphology, life history, and genetic diversity, and this high level of variation has made the taxonomy of the genus controversial. A significant population structure has been reported for the most widely distributed species, the common bottlenose dolphin (T. truncatus), in almost all ocean basins, though no data have been available for the western North Pacific Ocean (WNP). The genetic diversity of bottlenose dolphins in the WNP was investigated based on 20 microsatellite and one mitochondrial DNA markers for samples collected from Taiwanese, Japanese, and Philippine waters (9°–39°N, 120°–140°E) during 1986–2012. The results indicated that there are at least four genetically differentiated populations of common bottlenose dolphins in the western and central North Pacific Ocean. The pattern of differentiation appears to correspond to habitat types, resembling results seen in other populations of the same species. Our analyses also showed that there was no evident gene flow between the two “sister species”, the common bottlenose dolphins, and the Indo-Pacific bottlenose dolphins (T. aduncus) occurring sympatrically in our study region.

Molecular characterization and epidemic history of hepatitis C virus using core sequences of isolates from Central Province, Saudi Arabia.

The source of HCV transmission in Saudi Arabia is unknown. This study aimed to determine HCV genotypes in a representative sample of chronically infected patients in Saudi Arabia. All HCV isolates were genotyped and subtyped by sequencing of the HCV core region and 54 new HCV isolates were identified. Three sets of primers targeting the core region were used for both amplification and sequencing of all isolates resulting in a 326 bp fragment. Most HCV isolates were genotype 4 (85%), whereas only a few isolates were recognized as genotype 1 (15%). With the assistance of Genbank database and BLAST, subtyping results showed that most of genotype 4 isolates were 4d whereas most of genotype 1 isolates were 1b. Nucleotide conservation and variation rates of HCV core sequences showed that 4a and 1b have the highest levels of variation. Phylogenetic analysis of sequences by Maximum Likelihood and Bayesian Coalescent methods was used to explore the source of HCV transmission by investigating the relationship between Saudi Arabia and other countries in the Middle East and Africa. Coalescent analysis showed that transmissions of HCV from Egypt to Saudi Arabia are estimated to have occurred in three major clusters: 4d was introduced into the country before 1900, the major 4a clade’s MRCA was introduced between 1900 and 1920, and the remaining lineages were introduced between 1940 and 1960 from Egypt and Middle Africa. Results showed that no lineages seem to have crossed from Egypt to Saudi Arabia in the last 15 years. Finally, sequencing and characterization of new HCV isolates from Saudi Arabia will enrich the HCV database and help further studies related to treatment and management of the virus.

RAPD and ISSR marker assessment of genetic diversity in Citrullus colocynthis (L.) Schrad: a unique source of germplasm highly adapted to drought and high-temperature stress.

Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) shows high levels of variation in fruit color, fruit stripe pattern, seed coat color, and size. Thirty-eight accessions of C. colocynthis plants from different parts of semi-arid Rajasthan were collected and genetic diversity was assessed using random-amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. Out of 65 RAPD decamer primers, 50 primers produced 549 scorable bands of which 318 were polymorphic. Polymorphic banding patterns with the number of amplified fragments varied from 5 (OPA-08 and OPF-9) to 19 (OPT-20) in the molecular size range of 150-6000bp. Percent polymorphism ranged from 22.2% (OPA-09) to 83.3% (OPE-12) with 55.14% polymorphism. Out of the 20 ISSR primers screened, 13 primers produced 166 amplification products, of which 99 were polymorphic. The number of bands amplified per primer varied between 9 (UBC-807, 802) and 16 (UBC-803, 812) with average band size between 250 and 4000bp. Percent polymorphism ranged from 45.4% (UBC-815) to 73.3% (UBC-814) with 65.05% polymorphism. Dendrogram constructed on the basis of RAPD+ISSR polymorphism separated the accessions into four distinct clusters at 72% variation with Jaccard's similarity coefficient ranging from minimum 0.64 to 0.95. The matrices for RAPD and ISSR were also compared using Mantel's test and obtained correlation value (r=0.7947). Discriminating power of RAPD and ISSR markers was assessed by calculating polymorphic information content, multiplex ratio, marker index, and resolving power. Approx. 50% RAPD and ISSR markers showed PIC value and heterozygosity (H)≥0.50, indicating marker as informative. The primers that showed higher polymorphism had higher RP, MR, and MI values.

Species delimitation in frogs from South American temperate forests: The case of Eupsophus, a taxonomically complex genus with high phenotypic variation.

One of the most characteristic and abundant amphibian taxa of South American temperate forests is Eupsophus. The ten currently recognized species of the genus have been divided in two species groups, roseus and vertebralis, but most of them, eight, belong to the roseus group. Recent phylogeographic and phylogenetic studies have suggested that species diversity of the roseus group could be underestimated. An examination of the literature shows that species of the roseus group exhibit high levels of variation in their external characteristics, particularly those used as diagnostic characters, which compromises their taxonomy and hinders their field recognition. High levels of variation were also observed in several new populations of the roseus group discovered in southern Chile (36°-40°S), which could not be identified to the species level by their external characteristics. On the other hand, the literature reveals a scarse karyotype differentiation and a high bioacoustic uniformity among the species of the roseus group. We performed a Bayesian phylogenetic analysis using mitochondrial and nuclear genes to reevaluate the species diversity of the roseus group, including all the nominal species of Eupsophus and new populations. This analysis was complemented with three species delimitation approaches, General Mixed Yule Coalescent, multi-rate Poisson Tree Process and Automatic Barcode Gap Discovery. We favored a conservative delimitation of only four species for the roseus group, a result more consistent with the distribution of pairwise genetic distances, and the available chromosome and bioacoustic evidence. The four recognized lineages, which have nearly completely allopatric distributions, are named after the earliest nominal species that they include, but because high levels of phenotypic variation, they are not diagnosable by consistent differences in external morphology. We discuss the implications of this new proposal for the taxonomy and conservation of the genus, and the possible causes of the difficulty to estimate its species diversity.

River-specific macrogenomic diversity in Simulium guianense s. l. (Diptera: Simuliidae), a complex of tropical American vectors associated with human onchocerciasis.

Simulium guianense Wise is a Latin American vector complex of black flies associated with transmission of the causal agent of human onchocerciasis (river blindness). An analysis of the chromosomal banding patterns of 607 larvae of S. guianense s. l. revealed a high level of variation involving 83 macrogenomic rearrangements across 25 populations in Brazil, French Guiana, and Venezuela. The 25 populations were assigned to 13 cytoforms (A1, A2, B1–B4, C, D, E1–E4, and F), some of which are probably valid species. Based on geographical proximity, a member of the B group of cytoforms probably represents the name-bearing type specimen of S. guianense and the primary vector in the last-remaining onchocerciasis foci in the Western Hemisphere. Cytoform B3 in Amapá State is implicated as an anthropophilic simuliid in an area currently and historically free of onchocerciasis. Distributions of cytoforms are associated with geography, elevation, and drainage basin, and are largely congruent with ecoregions. Despite extraordinarily large larval populations of S. guianense s. l. in big rivers and consequent production of female flies for dispersal, the cytoforms maintain their chromosomal distinction within individual rivers, suggesting a high degree of fidelity to the specialized breeding habitats—rocky shoals—of the natal rivers.

Integration of wild and captive genetic management approaches to support conservation of the endangered Japanese golden eagle

The loss of biological diversity within species has the potential to significantly reduce resilience in the face of environmental change. Conservation of genetic variation needs to consider all available sources of diversity within a species, and approaches are required to integrate population management across traditionally separate wild and captive population domains. Here we report on a study that utilises different types of genetic analysis at different taxonomic scales and across an in situ – ex situ transition to support conservation planning for the Japanese golden eagle, a subspecies in serious regional decline. Mitochondrial DNA sequencing and nuclear DNA profiling are used to investigate subspecies differentiation and diversity in the natural population, revealing relatively high levels of variation in Japan. These results are compared with data from a newly established conservation breeding programme that indicates good representation of wild genetic variation in the captive founders. However, subsequent population viability analysis (PVA) to examine the demographic and genetic future of the captive population demonstrates the severe effects of existing reproductive skews, suggesting that this population is not sustainable without intensive genetic management. Lastly, the use of available molecular tools to validate and reconstruct pedigrees in Japanese golden eagle are evaluated and discussed in the context of captive and wild conservation management. The paper highlights the importance of producing and utilising comparative molecular genetic data across the population management spectrum and the benefits of PVA to support the implementation of integrated conservation plans.

The association between the physical environment and the well-being of older people in residential care facilities: A multilevel analysis.

To investigate the associations between the quality of the physical environment and the psychological and social well-being of older people living in residential care facilities. Many older people in care facilities have cognitive and physical frailties and are at risk of experiencing low levels of well-being. High-quality physical environments can support older people as frailty increases and promote their well-being. Although the importance of the physical environment for residents' well-being is recognized, more research is needed. A cross-sectional survey of 20 care facilities from each of which 10 residents were sampled. As the individual resident data were nested in the facilities, a multilevel analysis was conducted. Data were collected during 2013 and 2014. The care facilities were purposely sampled to ensure a high level of variation in their physical characteristics. Residents' demographic and health data were collected via medical records and interviews. Residents' well-being and perceived quality of care were assessed via questionnaires and interviews. Environmental quality was assessed with a structured observational instrument. Multilevel analysis indicated that cognitive support in the physical environment was associated with residents' social well-being, after controlling for independence and perceived care quality. However, no significant association was found between the physical environment and residents' psychological well-being. Our study demonstrates the role of the physical environment for enhancing the social well-being of frail older people. Professionals and practitioners involved in the design of care facilities have a responsibility to ensure that such facilities meet high-quality specifications.

The Complete Chloroplast Genome of Chinese Bayberry (Morella rubra, Myricaceae): Implications for Understanding the Evolution of Fagales.

Morella rubra (Myricaceae), also known as Chinese bayberry, is an economically important, subtropical, evergreen fruit tree. The phylogenetic placement of Myricaceae within Fagales and the origin of Chinese bayberry’s domestication are still unresolved. In this study, we report the chloroplast (cp) genome of M. rubra and take advantage of several previously reported chloroplast genomes from related taxa to examine patterns of evolution in Fagales. The cp genomes of three M. rubra individuals were 159,478, 159,568, and 159.586 bp in length, respectively, comprising a pair of inverted repeat (IR) regions (26,014–26,069 bp) separated by a large single-copy (LSC) region (88,683–88,809 bp) and a small single-copy (SSC) region (18,676–18,767 bp). Each cp genome encodes the same 111 unique genes, consisting of 77 different protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes, with 18 duplicated in the IRs. Comparative analysis of chloroplast genomes from four representative Fagales families revealed the loss of infA and the pseudogenization of ycf15 in all analyzed species, and rpl22 has been pseudogenized in M. rubra and Castanea mollissima, but not in Juglans regia or Ostrya rehderiana. The genome size variations are detected mainly due to the length of intergenic spacers rather than gene loss, gene pseudogenization, IR expansion or contraction. The phylogenetic relationships yielded by the complete genome sequences strongly support the placement of Myricaceae as sister to Juglandaceae. Furthermore, seven cpDNA markers (trnH-psbA, psbA-trnK, rps2-rpoC2, ycf4-cemA, petD-rpoA, ndhE-ndhG, and ndhA intron) with relatively high levels of variation and variable cpSSR loci were identified within M. rubra, which will be useful in future research characterizing the population genetics of M. rubra and investigating the origin of domesticated Chinese bayberry.

Schools at the Rural-Urban Boundary - Blurring the Divide?

Schools mirror the communities in which they are located. Research on school inequality across the rural-urban spectrum tends to focus on the contrast between urban, suburban, and rural schools and glosses over the variation within these areas as well as the similarities between them. To address this gap and provide a richer description of the spatial distribution of educational inequality, we examine the school composition, achievement, and resources of all U.S. elementary schools in 2010-2011. We apply standard census definitions of what areas fall within central cities, the remainder of metropolitan regions, and in rural America. We then apply spatially explicit methods to reveal blurred boundaries and gradual gradients rather than sharp breaks at the edges of these zones. The results show high levels of variation within the suburbs and substantial commonality between rural and urban areas.

Third person present tense markers in some varieties of English

AbstractIn British Standard English, number in the verb phrase is exclusively characterized by the use of the -sinflection with the third person singular present tense. World Englishes present a high level of variation as the uninflected third person singular and the inflected third person plural may also occur in these contexts. This paper pursues four objectives: a) to analyse the use of present third person inflections and compare their distribution in different varieties of English; b) to assess the occurrence of forms across speech and writing, text categories and the informants’ age and gender; c) to classify the instances by type of subject (nominal vs. pronominal); and d) to evaluate the impact of proximity agreement, notional agreement and the existence of intervening elements in the choice of the inflection. Our evidence comes from the New Zealand, Indian, Singaporean and Hong Kong components of the International Corpus of English.

Constitutive differences in glucocorticoid responsiveness to stress are related to variation in aggression and anxiety-related behaviors

Glucocorticoids coordinate responses that enable an individual to cope with stressful challenges and, additionally, mediate adaptation following cessation of a stressor. There are important individual differences in the magnitude of glucocorticoid responsiveness to stressors. However, whether individual differences in glucocorticoid responsiveness to stress are linked to different behavioral strategies in coping with social and non-social challenges is not easily studied, owing to the lack of appropriate animal models. To address this, we generated three lines of Wistar rats selectively bred for the magnitude of their glucocorticoid responses following exposure to a variety of stressors over three consecutive days at juvenility. Here, we present findings following observations of a high level of variation in glucocorticoid responsiveness to stress in outbred Wistar rats, and the strong response to selection for this trait over a few generations. When challenged with different stressful challenges, rats from the three lines differed in their coping behaviors. Strikingly, the line with high glucocorticoid responsiveness to stress displayed enhanced aggression and anxiety-like behaviors. In addition, these rats also showed alterations in the expression of genes within both central and peripheral nodes of the hypothalamic-pituitary-adrenal (HPA) axis and enhanced reactivity to acute stress exposure. Together, these findings strongly link differences in glucocorticoid responsiveness to stress with marked differences in coping styles. The developed rat lines are thus a promising model with which to examine the relationship between variation in reactivity of the HPA axis and stress-related pathophysiology and could be employed to assess the therapeutic potential of treatments modulating stress habituation to ameliorate psychopathology.

Phytochemical and Yield Variation among Iranian Achillea millefolium Accessions

Chemical composition and essential oil yields from aerial parts of 31 Iranian Achillea millefolium accessions, each collected from their natural habitats of Iran and grown together in field conditions, were investigated. The concentrations of the hydro-distilled essential oils ranged from 0.03% to 0.39%. Gas chromatography–mass spectrometry (GC–MS) analysis revealed 50 compounds in the accessions. The main components of the essential oils in Iranian A. millefolium accessions varied in the following ranges: 1,8-Cineole, 1.2–19.8%; β-thujone, 0.4–55.3%; camphor, 0.6–25.5%; germacrene-D, 2–20.6%; trans-nerolidol, 0.4–48.1%; isospathulenol, 0.5–36%; and cubenol, 0.1–42.9%. According to cluster analysis, five chemotypes were obtained as 1,8-Cineole/trans-nerolidol, high cubenol, high germacrene-D/isospathulenol, high camphor/cubenol, and high 1,8-Cineole/ β-thujone/cubenol. The result of principal component analysis (PCA) indicated that germacrene-D and isospathulenol components were under more genetic control than the other main components. Results revealed a high level of variation of composition and yield of essential oils among the Iranian A. millefolium accessions.

Altered CRYPTOCHROME Expression Profile is Correlated with Reduced Circadian Clock Plasticity in the yellow white, Drosophila melanogaster

The circadian clock that regulates behavior and physiology of animals is synchronized to the natural, 24 hour, light-dark cycle primarily by light. In Drosophila melanogaster, light is transduced to the clock neurons via the external photoreceptors in addition to the blue-light photopigment, CRYPTOCHROME (CRY), which plays a special role in clock phase resetting. Previous studies showed that the y w mutation in D. melanogaster is correlated with altered locomotor and molecular circadian rhythms, probably due to their disturbed eye pigmentation and sensitivity, and neurotransmitter physiology. This study investigates the relationship between this mutation and the CRY expression profile as a primary player in the photic entrainment pathway. Results revealed that CRY levels was most of the time higher in y w mutants compared to the wild-type CS fruit flies in all clock neuronal clusters expressing CRY. The reduced and delayed degradation of CRY indicates week photoreception by the mutants and provides a possible explanation for the delayed PERIOD (PER) and suppressed Pigment-Dispersing Factor (PDF) signaling detected previously. It could also explain the delayed morning and advanced evening locomotor activity peaks of these y w mutants. The results also showed a higher level of variation in CRY staining between individual neurons within each cluster, probably due to reduced PDF signaling which is known to internally synchronize clock neurons. It could be concluded that, the mutations affecting the photic entrainment pathway to the circadian clock, like the y w mutation, would probably have widespread effects on the circadian clock machinery and the overt rhythms under its regulation