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We address the following rainbow Ramsey problem: For posets P, Q what is the smallest number n such that any coloring of the elements of the Boolean lattice Bn either admits a monochromatic copy of P or a rainbow copy of Q. We consider both weak and strong (non-induced and induced) versions of this problem.

Primary cardiac manifestation is a common complication of systemic sclerosis (SSc) with poor prognosis. The aim of the current study was to detect potential myocardial inflammation present in asymptomatic SSc patients by 18F-FDG-PET/CT and to investigate its relationship with early signs of myocardial dysfunction as detected by 2D speckle tracking echocardiography (2DSTE).Sixteen consecutive patients with SSc and 9 control patients without clinical evidence of cardiac involvement were enrolled in the study. On 18F-FDG-PET acquired images blood-pool normalised SUV ratio and heterogenity index (HI: standard deviation of SUV divided with mean SUV) were calculated. Within 24 hours all SSc patients underwent 2DSTE strain analysis.Eight of 16 SSc patients were found to be visually PET-positive and showed significantly higher myocardial 18F-FDG SUV ratio (1.78±0.74 vs. 0.98±0.03; p0.05) and heterogenity index (0.13±0.02 vs. 0.05±0.02; p0.001) as compared to the control group. FDG-PET/CT derived values did not differ significantly between visually PET-negative (8/16) and control patients (SUV ratio: 0.98±0.05 vs. 0.98±0.03; HI: 0.05±0.01 vs. 0.05±0.02). Global left ventricular longitudinal strain values did not differ significantly between PET-positive and negative patients (17.18±3.49% vs. 17.59±3.65%).Myocardial inflammation, as a potential sign of early cardiac involvement can be detected by 18-FDG-PET/CT in a considerable percentage of systemic sclerosis patients presenting without cardiac symptoms.

Cobras are among the most widely known venomous snakes, and yet their taxonomy remains incompletely understood, particularly in Africa. Here, we use a combination of mitochondrial and nuclear gene sequences and morphological data to diagnose species limits within the African forest cobra, Naja (Boulengerina) melanoleuca. Mitochondrial DNA sequences reveal deep divergences within this taxon. Congruent patterns of variation in mtDNA, nuclear genes and morphology support the recognition of five separate species, confirming the species status of N. subfulva and N. peroescobari, and revealing two previously unnamed West African species, which are described as new: Naja (Boulengerina) guineensis sp. nov. Broadley, Trape, Chirio, Ineich & Wüster, from the Upper Guinea forest of West Africa, and Naja (Boulengerina) savannula sp. nov. Broadley, Trape, Chirio & Wüster, a banded form from the savanna-forest mosaic of the Guinea and Sudanian savannas of West Africa. The discovery of cryptic diversity in this iconic group highlights our limited understanding of tropical African biodiversity, hindering our ability to conserve it effectively.

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.

In this erratum, we correct the abstract and introduction of Opt. Lett.43, 1742 (2018)OPLEDP0146-959210.1364/OL.43.001742 to not include a wrong name for the crystal.

The Congolese and Lower Guinean ichthyological provinces are understudied hotspots of the global fish diversity. Here, we barcoded 741 specimens from the Lower and Middle Congo River and from three major drainage basins of the Lower Guinean ichthyological province, Kouilou‐Niari, Nyanga and Ogowe. We identified 194 morphospecies belonging to 82 genera and 25 families. Most morphospecies (92.8%) corresponded to distinct clusters of DNA barcodes. Of the four morphospecies present in both neighbouring ichthyological provinces, only one showed DNA barcode divergence

The aim of the study was to examine the determining factors of students' video usage and their learning satisfaction relating to the supplementary application of educational videos, accessible in a Moodle environment in a Business Mathematics Course. The research model is based on the extension of Technology Acceptance Model (TAM), in which the core TAM constructs – perceived usefulness, perceived ease of use, attitude – and internet self-efficacy were included as the explanatory factors of video usage. As regards the determinants of learning satisfaction, beside the core TAM constructs, the role of learning performance, learner-learner interaction, and learner-teacher interaction was examined. Data were collected from 89 students using a questionnaire, on which the partial least-squares structural equation modelling approach was used to evaluate the research model. The results confirmed that perceived usefulness, attitude, and internet self-efficacy had a direct effect on the video usage. Learning satisfaction was directly influenced by learner-learner interaction, perceived ease of use, and learning performance. Furthermore, the results indicated that video usage had a significant effect both on learning performance and on learning satisfaction. The findings show that the extended TAM model can be applied for predicting the university students' video technology usage and their learning satisfaction regarding the usage.

We study the relationship between the sizes of two sets $B, S\subset\mathbb{R}^2$ when $B$ contains either the whole boundary, or the four vertices, of a square with axes-parallel sides and center in every point of $S$, where size refers to one of cardinality, Hausdorff dimension, packing dimension, or upper or lower box dimension. Perhaps surprinsingly, the results vary depending on the notion of size under consideration. For example, we construct a compact set $B$ of Hausdorff dimension $1$ which contains the boundary of an axes-parallel square with center in every point $[0,1]^2$, but prove that such a $B$ must have packing and lower box dimension at least $\tfrac{7}{4}$, and show by example that this is sharp. For more general sets of centers, the answers for packing and box counting dimensions also differ. These problems are inspired by the analogous problems for circles that were investigated by Bourgain, Marstrand and Wolff, among others., Comment: 20 pages, no figures

Materials used for the oil and gas industry are exposed to high pressure, high temperature and several aggressive fluids and gases. Concerning the still rising oil and gas product demand the development of new oil and gas valves is indispensable. Therefore, new reliable materials to guarantee facility safety at extreme operating conditions are needed. The presented study deals with a specific failure, the rapid gas decompression failure, which occurs due to the exposure to such extreme conditions. This failure leads to crack initiation, crack growth and in the worst case to the complete fragmentation of the component. For the characterization of this failure a hydrogenated acrylonitrile butadiene based rubber with an acrylonitrile content of 36% was exposed to several temperatures, saturation pressures, gas mixtures and different depressurization rates. Whereas, the rising testing temperature leads to decreasing volume change during the depressurization, the increase in saturation pressure, a higher decompression rate and a higher amount of carbon dioxide clearly lead to an increasing of the maximum observed volume change. Based on the observed volume change and the material ranking, determined using common testing standards NACE International (2003) and NORSOK (2001) a correlation to polymer physical principals was established.

Soldierless termites are extremely abundant in South America where they account for up to one-third of the termite species richness. However, their diversity has mostly been addressed through scattered, indecisive descriptions, leaving large gaps in our understanding of termite diversity. Here, to progress towards a more complete knowledge of this group, we redescribe the genus Grigiotermes and describe five new genera, Amplucrutermes, Humutermes, Hydrecotermes, Patawatermes, and Rubeotermes, comprising a total of nine species. We reassign four species to new genera, synonymize two species, and provide extensive descriptions and diagnoses for all taxa included here. We also provide a molecular phylogeny of selected Neotropical and Old World Apicotermitinae and provide a key to the genera of Neotropical workers to facilitate identification. © 2015 The Linnean Society of London

The Persian dwarf snake Eirenis (Pseudocyclophis) persicus (Anderson, 1872) has a wide distribution range in south-western Asia. This species group was comprehensively studied here using traditional biometry, geometric morphometrics, ecological niche modelling, and genetics. Our analyses revealed that E. persicus is split into two clades. A western clade, bearing at least two different species: E. persicus, distributed in south-western Iran, and an undescribed species from south-eastern Turkey and western Iran. The eastern clade consists of at least three species: Eirenis nigrofasciatus, distributed across north-eastern Iraq, and western and southern Iran; Eirenis walteri, distributed across eastern Iran, southern Turkmenistan, and western and southern Pakistan, and Eirenis angusticeps, distributed in north-eastern Pakistan. Ecological niche modelling revealed that the distribution of the species in the western clade are mainly affected by winter precipitation, and those in the eastern clade are mainly affected by the minimum temperature of the coldest month. A molecular clock analysis revealed that the divergence and diversification of the E. persicus species group mainly correspond to Eocene to Pliocene orogeny events subsequent to the Arabia–Eurasia collision. This study confirms that specimens with the unique morphology of having 13 dorsal scale rows on the anterior dorsum, occurring in the Suleiman Mountains in central Pakistan, can be referred to Eirenis mcmahoni (Wall, 1911). However, at this moment we have insufficient data to evaluate the taxonomy of this species.

Using up to 2117 bp of mitochondrial DNA and up to 2012 bp of nuclear DNA, we analysed phylogeographic differentiation of six widely distributed species of African hinged terrapins (Pelusios spp.) representing different habitat types. Two taxa each live in savannahs or in forests and mesic savannahs, respectively, and the remaining two species occur in intermediate habitats. The species living in forests and mesic savannahs do not enter dry savannahs, whereas the savannah species may occur in dry and wet savannahs and even in semi-arid steppe regions. We found no obvious correlation between habitat type and phylogeographic pattern: one savannah species (P. rhodesianus) shows phylogeographic structure, i.e. pronounced genetic differences among geographically distinct populations, and the other (P. nanus) not. One species inhabiting forests and mesic savannahs (P. carinatus) has phylogeographic structure, the other (P. gabonensis) not. The same pattern is true for the two ecologically intermediate species, with phylogeographic structure present in P. castaneus and absent in P. chapini. Nuclear evidence suggests that the latter two taxa with abutting and partially overlapping ranges are distinct, while mtDNA is only weakly differentiated. Pelusios castaneus shows pronounced phylogeographic structure, which could reflect Pleistocene range interruptions correlated with the fluctuating forest cover in West and Central Africa. Our results do not support the recognition of an extinct subspecies of P. castaneus for the Seychelles. Pelusios carinatus contains two well supported clades, which are separated by the Congo River. This species is closely related to P. rhodesianus, a taxon consisting of two deeply divergent mitochondrial clades. One of these clades is paraphyletic with respect to P. carinatus, but the two clades of P. rhodesianus are not differentiated in the studied nuclear markers and, again, paraphyletic with respect to P. carinatus. Using mtDNA sequences from the type material of P. rhodesianus, we were able to allocate this name to one of the two clades. However, owing to the confusing relationships of P. rhodesianus and P. carinatus, we refrain from taxonomic decisions.

Aim : Although most reptiles are oviparous, viviparity is a commonmode of reproduction in squamates and has evolved multiple times in different lineages.We test two prevailing hypotheses regarding the biogeography of reptile reproductive modes to evaluate the selective forces driving the evolution of viviparity in snakes. The cold climate hypothesis posits that viviparity is selected for in cold climates, whereas the climatic predictability hypothesis predicts that viviparity is advantageous in seasonal climates. Methods : We collated detailed distribution maps and reproductive mode data for 2663 species of the world’s terrestrial alethinophidian snakes.We studied the relationship between snake reproductive mode and environmental predictors. We applied both an ecological and an evolutionary approach to study snake reproductive mode by performing the analyses at the assemblage level and species level, respectively. We analysed our data at the global and continental scales to learn whether tendencies to viviparity are similar world-wide. Results : We found strong support for the cold climate hypothesis and the assumption that viviparity is an adaptation to cold environments. There was little support for the climatic predictability hypothesis. Nonetheless, viviparous species are not restricted to cold environments. Main conclusions : We conclude that viviparity is adaptive in cold climates, but not necessarily in unpredictable/seasonal climates. Current distributions may not reflect the climate at the time and place of speciation.We suspect many viviparous snakes inhabiting warm climates are members of lineages that originated in colder regions, and their occurrence in maladaptive environments is a result of phylogenetic conservatism.

Using online video presentations is increasingly gaining ground in higher education. Our present paper discusses the initial results of a longer research project and investigates the effect that the availability of online videos introduced to complement live presentations has on learning performance. The quasi-experimental research covered each college year and each course of the college including the business faculty. Results have shown that the availability of online videos resulted in significant improvement in semester grades and it contributed to reducing dropout rates.

In this paper we are investigating the holonomy structure of Finsler 2-manifolds. We show that the topological closure of the holonomy group of a certain class of projectively flat Finsler 2-manifolds of constant curvature is maximal, that is isomorphic to the connected component of the diffeomorphism group of the circle. This class of 2-manifolds contains the standard Funk plane of constant negative curvature and the Bryant–Shen-spheres of constant positive curvature. The result provides the first examples describing completely infinite dimensional Finslerian holonomy structures.

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Members of the snake subfamily Aparallactinae occur in various habitats throughout sub-Saharan Africa. The monophyly of aparallactine snakes is well established, but relationships within the subfamily are poorly known. We sampled 158 individuals from six of eight aparallactine genera in sub-Saharan Africa. We employed concatenated gene-tree analyses, divergence dating approaches, and ancestral-area reconstructions to infer phylogenies and biogeographic patterns with a multi-locus data set consisting of three mitochondrial (16S, cyt b, and ND4) and two nuclear genes (c-mos and RAG1). As a result, we uncover several cryptic lineages and elevate a lineage of Polemon to full species status. Diversification occurred predominantly during the Miocene, with a few speciation events occurring subsequently in the Pliocene and Pleistocene. Biogeographic analyses suggested that the Zambezian biogeographic region, comprising grasslands and woodlands, facilitated radiations, vicariance, and dispersal for many aparallactines. Moreover, the geographic distributions of many forest species were fragmented during xeric and cooler conditions, which likely led to diversification events. Biogeographic patterns of aparallactine snakes are consistent with previous studies of other sub-Saharan herpetofauna.

A subfamily $$\{F_1,F_2,\dots ,F_{|P|}\}\subseteq {{\mathcal {F}}}$${F1,F2,⋯,F|P|}⊆F is a copy of the poset P if there exists a bijection $$i:P\rightarrow \{F_1,F_2,\dots ,F_{|P|}\}$$i:P→{F1,F2,⋯,F|P|}, such that $$p\le _P q$$p≤Pq implies $$i(p)\subseteq i(q)$$i(p)⊆i(q). A family $${{\mathcal {F}}}$$F is P-free, if it does not contain a copy of P. In this paper we establish basic results on the maximum number of k-chains in a P-free family $${{\mathcal {F}}}\subseteq 2^{[n]}$$F⊆2[n]. We prove that if the height of P, $$h(P) > k$$h(P)>k, then this number is of the order $$\Theta (\prod _{i=1}^{k+1}\left( {\begin{array}{c}l_{i-1}\\ l_i\end{array}}\right) )$$Θ(∏i=1k+1li-1li), where $$l_0=n$$l0=n and $$l_1\ge l_2\ge \dots \ge l_{k+1}$$l1≥l2≥⋯≥lk+1 are such that $$n-l_1,l_1-l_2,\dots , l_k-l_{k+1},l_{k+1}$$n-l1,l1-l2,⋯,lk-lk+1,lk+1 differ by at most one. On the other hand if $$h(P)\le k$$h(P)≤k, then we show that this number is of smaller order of magnitude. Let $$\vee _r$$∨r denote the poset on $$r+1$$r+1 elements $$a, b_1, b_2, \ldots , b_r$$a,b1,b2,…,br, where $$a < b_i$$a

The relationship between the atmospheric concentration of cosmogenic isotopes, the change of solar activity and hence secondary neutron flux has already been proven. The temporal atmospheric variation of the most studied cosmogenic isotopes shows a significant anti-correlation with solar cycles. However, since artificial tritium input to the atmosphere due to nuclear-weapon tests masked the expected variations of tritium production rate by three orders of magnitude, the natural variation of tritium in meteoric precipitation has not previously been detected. For the first time, we provide clear evidence of the positive correlation between the tritium concentration of meteoric precipitation and neutron flux modulated by solar magnetic activity. We found trends in tritium time series for numerous locations worldwide which are similar to the variation of secondary neutron flux and sun spot numbers. This variability appears to have similar periodicities to that of solar cycle. Frequency analysis, cross correlation analysis, continuous and cross wavelet analysis provide mathematical evidence that the correlation between solar cycle and meteoric tritium does exist. Our results demonstrate that the response of tritium variation in precipitation to the solar cycle can be used to help us understand its role in the water cycle.

A metric Lie algebra is a Lie algebra endowed with a Euclidean inner product. A subalgebra is called flat, respectively totally geodesic, if its exponential image in the corresponding Lie group with left invariant Riemannian metric is flat, respectively a totally geodesic submanifold. A non-zero vector is geodesic, if the generated one-dimensional subspace is totally geodesic. We study geodesic vectors and flat totally geodesic subalgebras in two-step nilpotent metric Lie algebras and show that their linear structure is independent of the inner product of the metric Lie algebra. We determine the geodesic vectors and the flat totally geodesic subalgebras in the two-step nilpotent metric Lie algebras of dimension ≤ 6.

Thermobifidas are thermophilic, aerobic, lignocellulose decomposing actinomycetes. The Thermobifida genus includes four species: T. fusca, T. alba, T. cellulosilytica, and T. halotolerans. T. fusca YX is the far best characterized strain of this taxon and several cellulases and hemicellulases have been cloned from it for industrial purposes targeting paper industry, biofuel, and feed applications. Unfortunately, sequence data of such enzymes are almost exclusively restricted to this single species; however, we demonstrated earlier by zymography that other T. alba and T. cellulosilytica strains encode the same enzyme sets. Recently, the advances in whole genome sequencing by the use of next generation genomics platforms accelerated the selection process of valuable hydrolases from uncharacterized bacterial species for cloning purposes. For this purpose T. cellulosilytica TB100(T) type strain was chosen for de novo genome sequencing. We have assembled the genome of T. cellulosilytica strain TB100(T) into 168 contigs and 19 scaffolds, with reference length of 4 327 869 bps, 3 589 putative coding sequences, 53 tRNAs, and 4 rRNAs. The analysis of the annotated genome revealed the existence of 27 putative hydrolases belonging to 14 different glycoside hydrolase (GH) families. The investigation of identified, cloned, and heterologously multiple cellulases, mannanases, xylanases, and amylases may result in industrial applications beside gaining useful basic research related information.

Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co-distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo-Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species-specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo-Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species.

Meadow vipers (Vipera ursinii–renardi complex) are small-bodied snakes that live in either lowland grasslands or montane subalpine-alpine meadows spanning a distribution from France to western China. This complex has previously been the focus of several taxonomic studies which were based mainly on morphological, allozyme or immunological characters and did not clearly resolve the relationships between the various taxa. Recent mitochondrial DNA analyses found unexpected relationships within the complex which had taxonomical consequences for the detected lineages. The most surprising was the basal phylogenetic position of Vipera ursinii graeca, a taxon described almost 30 years ago from the mountains of Greece. We present here new analyses of three nuclear markers (BDNF, NT3, PRLR; a first for studies of meadow and steppe vipers) as well as analyses of newly obtained mitochondrial DNA sequences (CYT B, ND4).Our Bayesian analyses of nuclear sequences are concordant with previous studies of mitochondrial DNA, in that the phylogenetic position of the graeca clade is a clearly distinguished and distinct lineage separated from all other taxa in the complex. These phylogenetic results are also supported by a distinct morphology, ecology and isolated distribution of this unique taxon. Based on several data sets and an integrative species concept we recommend to elevate this taxon to species level: Vipera graeca Nilson & Andrén, 1988 stat. nov.

Nowadays the main task of scientists is to find natural ways of improving plant productivity that lead to environmentally friendly agriculture. Biofertilizers have a great potential to achieve this aim but unfortunately there is little information about their application in grape growing in Hungary. For this reason, a foliar nutrition experiment was conducted to investigate the effect of two biofertilizers (an algae product and a biostimulator, containing amino acids) on yield, leaf nutrient concentration, and quality parameters of Blaufrankish grape variety. The study was conducted in 2012 at Noszvaj in northeastern Hungary in a 24-year-old grapevine plantation on cv. Blaufrankish. Treatments (application time and doses) were adjusted to the phenological phases of grapevine. Effect of treatments was monitored by soil and leaf analysis, grape quality measurements, and field observations. Treatments increased the yield but did not affect the fruit quality compared to the control. The applied products signi...

In a Quercetum petraeae–cerris forest in northeastern Hungary, we examined effects of litter input alterations on the quantity and quality soil carbon stocks and soil CO2 emissions. Treatments at the Sikfőkut DIRT (Detritus Input and Removal Treatments) experimental site include adding (by doubling) of either leaf litter (DL) or wood (DW) (including branches, twigs, bark), and removing all aboveground litter (NL), all root inputs by trenching (NR), or removing all litter inputs (NI). Within 4 years we saw a significant decrease in soil carbon (C) concentrations in the upper 15 cm for root exclusion plots. Decreases in C for the litter exclusion treatments appeared later, and were smaller than declines in root exclusion plots, highlighting the role of root detritus in the formation of soil organic matter in this forest. By year 8 of the experiment, surface soil C concentrations were lower than Control plots by 32% in NI, 23% in NR and 19% in NL. Increases in soil C in litter addition treatments were less than C losses from litter exclusion treatments, with surface C increasing by 12% in DL and 6% in DW. Detritus additions and removals had significant effects on soil microclimate, with decreases in seasonal variations in soil temperature (between summer and winter) in Double Litter plots but enhanced seasonal variation in detritus exclusion plots. Carbon dioxide (CO2) emissions were most influenced by detritus input quantity and soil organic matter concentration when soils were warm and moist. Clearly changes in detritus inputs from altered forest productivity, as well as altered litter impacts on soil microclimate, must be included in models of soil carbon fluxes and pools with expected future changes in climate.

In this first cytogenetic survey on the lamprophiid snake subfamily Pseudoxyrhophiinae, we studied the karyology of ten snake species belonging to seven genera from Madagascar (Compsophis, Leioheterodon, Liophidium, Lycodryas, Madagascarophis, Phisalixella and Thamnosophis) using standard and banding methods. Our results show a wide range of different karyotypes ranging from 2n = 34 to 2n = 46 elements (FN from 40 to 48), with nucleolus organizer regions (NORs) on one (plesiomorphic) or two (derived/apomorphic) microchromosome pairs, and W chromosome at early or advanced states of diversification from the Z chromosome. The observed W chromosome variations further support the most accepted hypothesis that W differentiation from the Z chromosome occurred by progressive steps. We also propose an evolutionary scenario for the observed high karyotype diversity in this group of snakes, suggesting that it is derived from a putative primitive pseudoxyrhophiine karyotype with 2n = 46, similar to that of Leioheterodon geayi, via a series of centric fusions and inversions among macrochromosomes and translocations of micro- either to micro- or to macrochromosomes. This primitive Pseudoxyrhophiinae karyotype might have derived from a putative Lamprophiidae ancestor with 2n = 48, by means of a translocation of a micro- to a macrochromosome. In turn, the karyotype of this lamprophiid common ancestor may have derived from the assumed primitive snake karyotype (2n = 36 chromosomes, with 16 biarmed macro- and 20 microchromosomes) by a series of centric fissions and one inversion. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112, 450–460.

We provide a DNA barcoding survey of Malagasy amphibians, including 251 of the 292 nominal species known to date, by complementing previous data with 280 newly determined barcoding sequence fragments of the mitochondrial cytochrome oxidase subunit I (COI) gene. Amplification success for the newly determined sequences was highest (94%) with one set of universal COI primers (dgLCO1490-dgHCO2198) while other primer sets had distinctly lower success rates. By and large, we observed relatively high average interspecific genetic distances of 25-27% within the Mantellidae and Microhylidae, and genetic distances of 13-21% within the Hyperoliidae. Lower values of 6-7% were observed between some sister species in all families, with extreme lows of 0.2-0.3% between a few sister species pairs in microhylids and mantellids for which we postulate mitochondrial introgression or yet unsettled taxonomy. Within-species divergences were relatively high especially in mantellids where they averaged 5.3%, due to the inclusion of numerous deep conspecific lineages (by definition with high divergences to other specimens) in our study. Above this, the degree of polymorphism was difficult to establish owing to limited sampling per population in our assessment. Compared to a previous assessment from 2009 based on 16S rDNA sequences, we identify 14 additional undescribed candidate species and raise the maximum estimate of species in the island’s batrachofauna to well over 500.

Empidoidea is one of the largest extant lineages of flies, but phylogenetic relationships among species of this group are poorly investigated and global diversity remains scarcely assessed. In this context, one of the most enigmatic empidoid families is Hybotidae. Within the framework of a pilot study, we barcoded 339 specimens of Old World hybotids belonging to 164 species and 22 genera (plus two Empis as outgroups) and attempted to evaluate whether patterns of intra- and interspecific divergences match the current taxonomy. We used a large sampling of diverse Hybotidae. The material came from the Palaearctic (Belgium, France, Portugal and Russian Caucasus), the Afrotropic (Democratic Republic of the Congo) and the Oriental realms (Singapore and Thailand). Thereby, we optimized lab protocols for barcoding hybotids. Although DNA barcodes generally well distinguished recognized taxa, the study also revealed a number of unexpected phenomena: e.g., undescribed taxa found within morphologically very similar or identical specimens, especially when geographic distance was large; some morphologically distinct species showed no genetic divergence; or different pattern of intraspecific divergence between populations or closely related species. Using COI sequences and simple neighbour-joining tree reconstructions, the monophyly of many species- and genus-level taxa was well supported, but more inclusive taxonomical levels did not receive significant bootstrap support. We conclude that in hybotids DNA barcoding might be well used to identify species, when two main constraints are considered. First, incomplete barcoding libraries hinder efficient (correct) identification. Therefore, extra efforts are needed to increase the representation of hybotids in these databases. Second, the spatial scale of sampling has to be taken into account, and especially for widespread species or species complexes with unclear taxonomy, an integrative approach has to be used to clarify species boundaries and identities.

The levels of heavy metals are very important in pistachio nuts, because the edible nuts have an important and increasing role in human nutrition. Pistachio is one of the native nuts of Iran which contains high genetic resources, but there is insufficient information regarding nutritional properties and other elements like heavy metals. The objective of the present study was to investigate and compare heavy metals contents in the kernels of various pistachio samples including; ‘Daneshmandi’, ‘Sephid’, ‘Garmeh’, ‘Momtaz’, ‘Ahmad Aghaei’, ‘Badami Zarand’, Pistacia atlantica Desf. (‘Baneh’), Pistacia vera ‘Sarakhs’ and chance seedling as ‘Non-grafted 1’, ‘Non-grafted 2’ and ‘Non-grafted 3’. Inductively coupled plasma emission spectrophotometer (ICP) was used for the determination of aluminium, chromium, nickel, copper, strontium, arsenic, cadmium and cobalt concentrations in pistachio kernels. This study showed that there were significant differences among the samples in all measured heavy metals except the arsenic, cadmium and cobalt. The content of aluminium varied from 3.22 to 9.59 (mg kg-1 of dry matter) and chromium concentration from 0.60 to 1.86 (mg kg-1 of dry matter). The nickel content of examined pistachio samples was found between 0.43 and 3.63 (mg kg-1 of dry matter) and copper ranged from 3.20 to 12.33 (mg kg-1 of dry matter). The strontium content was observed between 4.96 and 24.93 (mg kg-1 of dry matter). The contents of arsenic, cadmium and cobalt not reported, because their amounts were lower than the detection limit of the applied measuring method (ICP). These data demonstrated that the concentrations of heavy metals in pistachios varied by cultivar.

The pseudoxyrhophiine snake genus Liopholidophis Mocquard, 1904 (family Lamprophiidae) is endemic to Madagascar and according to its present definition comprises six medium-sized, terrestrial and diurnal snake species, most of which are characterised by an unusual and extreme sexual dimorphism in tail length. We performed molecular phylogenetic analyses using nucleotide sequences of three mitochondrial genes (16S rRNA, cytochrome b and cytochrome oxidase I) and one nuclear gene (c-mos) for all described and two additional species newly described herein. The two new species are very small sized (total length: 234–312.5 mm), have comparatively short tails and a reduced number of dorsal scale rows (15 at midbody), the lowest value among all non-scolecophidian snakes of Madagascar. Both species are secretive or rare, and they have a reddish belly in life that fades in preservative. In terms of colouration and morphology, they are most similar to each other and furthermore to Liopholidophis rhadinaea. Together with this species and L. dimorphus, they form a well-supported clade. Liopholidophis baderi sp. nov. from central eastern Madagascar is characterised by 149–158 ventrals and 71–77 subcaudals, whereas the similar L. oligolepis sp. nov. from the northeast has even fewer ventrals (137) and subcaudals (54). The phylogenetic tree suggests that the tail length dimorphism in the genus Liopholidophis has evolved in a complex pattern including at least one reversal. The phylogenetic position of the two new dwarf species indicates that both the absence of extreme sexual dimorphism in tail length and their body size reduction are derived and probably correlated features. Also the close phylogenetic relationships between the long-tailed L. sexlineatus and the similar but relatively short-tailed L. varius demonstrate that dimorphism in tail length can be strongly mitigated in short evolutionary time periods.

Herpetological surveys in the dry forests of the limestone massif Montagne des Francais in the far north of Madagascarhave recently yielded a number of undescribed reptile species. Here we describe an additional new and potentially microendemic species of the snake genus Madagascarophis (Squamata: Serpentes: Pseudoxyrhophiinae) which lives in this massif syntopically with M. colubrinus septentrionalis and differs distinctly from M. colubrinus and M. meridionalis in its mitochondrial and nuclear DNA sequences. Morphologically Madagascarophis fuchsi sp. nov. is characterized by a broad contact between the posterior inframaxillaries (genials), 25 dorsal scale rows at midbody, and a low number of ventrals (171–172). We re-describe the holotype of M. ocellatus and present new data on the morphological variation of the northern subspecies M. c. septentrionalis and M. c. citrinus . Although Montagne des Francais has recently been included into the network of nature reserves inMadagascar, continuous deforestation is strongly threatening this important center of reptile endemism. In line with the assessment of other microendemic reptiles of this massif we suggest to consider the new species as Critically Endangered according to the IUCN criteria and encourage new efforts to protect this area more efficiently

Cells must continuously repair inevitable DNA damage while avoiding the deleterious consequences of imprecise repair. Distinction between legitimate and illegitimate repair processes is thought to be achieved in part through differential recognition and processing of specific noncanonical DNA structures, although the mechanistic basis of discrimination remains poorly defined. Here, we show that Escherichia coli RecQ, a central DNA recombination and repair enzyme, exhibits differential processing of DNA substrates based on their geometry and structure. Through single-molecule and ensemble biophysical experiments, we elucidate how the conserved domain architecture of RecQ supports geometry-dependent shuttling and directed processing of recombination-intermediate [displacement loop (D-loop)] substrates. Our study shows that these activities together suppress illegitimate recombination in vivo, whereas unregulated duplex unwinding is detrimental for recombination precision. Based on these results, we propose a mechanism through which RecQ helicases achieve recombination precision and efficiency.

The maximum size, $La(n,P)$, of a family of subsets of $[n]=\{1,2,...,n\}$ without containing a copy of $P$ as a subposet, has been intensively studied. Let $P$ be a graded poset. We say that a family $\mathcal{F}$ of subsets of $[n]=\{1,2,...,n\}$ contains a \emph{rank-preserving} copy of $P$ if it contains a copy of $P$ such that elements of $P$ having the same rank are mapped to sets of same size in $\mathcal{F}$. The largest size of a family of subsets of $[n]=\{1,2,...,n\}$ without containing a rank-preserving copy of $P$ as a subposet is denoted by $La_{rp}(n,P)$. Clearly, $La(n,P) \le La_{rp}(n,P)$ holds. In this paper we prove asymptotically optimal upper bounds on $La_{rp}(n,P)$ for tree posets of height $2$ and monotone tree posets of height $3$, strengthening a result of Bukh in these cases. We also obtain the exact value of $La_{rp}(n,\{Y_{h,s},Y_{h,s}'\})$ and $La(n,\{Y_{h,s},Y_{h,s}'\})$, where $Y_{h,s}$ denotes the poset on $h+s$ elements $x_1,\dots,x_h,y_1,\dots,y_s$ with $x_1, Comment: 11 pages

The holonomy group of a Riemannian or Finslerian manifold can be introduced in a very natural way: it is the group generated by parallel translations along loops with respect to the canonical connection. The Riemannian holonomy groups have been extensively studied and by now their complete classification is known. On the Finslerian holonomy, however, only few results are known and, as our results show, it can be essentially different from the Riemannian one.

We used a 298 bp fragment of the mitochondrial cytochrome c oxidase subunit I gene (COI) to examine sequence variation in (mostly) museum specimens of the African Goshawk Accipiter tachiro. Our results showed two clades with high bootstrap support in a phylogenetic analysis and two groups in a nonmetric multidimensional scaling (NMDS) analysis. Each of the two phylogenetic clades corresponded to one of the NMDS groups. One clade comprised haplotypes of the subspecies A. t. lopezi, A. t. macroscelides, A. t. toussenelli and A. t. canescens and corresponded to the morphospecies A. toussenelii. This taxon has a more north-western distribution. The second clade comprised haplotypes of the subspecies A. t. sparsimfasciatus, A. t. pembaensis and A. t. tachiro and corresponded to the morphospecies A. tachiro, which has a more south-eastern distribution. Furthermore, one branch corresponded to the morphospecies A. t. unduliventer, which is confined to the Ethiopian highlands. The genetic divergence observed among the three A. tachiro morphospecies appeared concordant with the ecological and morphological divergence and suggests the existence of three putative species. Within A. tachiro and A. toussenelii there is substantial morphological, but very little genetic, differentiation among subspecies.Keywords: Accipiter tachiro, African Goshawk, COI, nonmetric multidimensional scaling, phylogeny, taxonomy

DNA barcoding facilitates the identification of species and the estimation of biodiversity by using nucleotide sequences, usually from the mitochondrial genome. Most studies accomplish this task by using the gene encoding cytochrome oxidase subunit I (COI; Entrez COX1). Within this barcoding framework, many taxonomic initiatives exist, such as those specializing in fishes, birds, mammals, and fungi. Other efforts center on regions, such as the Arctic, or on other topics, such as health. DNA barcoding initiatives exist for all groups of vertebrates except for amphibians and nonavian reptiles. We announce the formation of Cold Code, the international initiative to DNA barcode all species of these ‘cold-blooded’ vertebrates. The project has a Steering Committee, Coordinators, and a home page. To facilitate Cold Code, the Kunming Institute of Zoology, Chinese Academy of Sciences will sequence COI for the first 10 specimens of a species at no cost to the steward of the tissues.

Aim We assessed genetic relationships among populations for each of the four snake species found on Crete (Zamenis situla, Hierophis gemonensis, Telescopus fallax and Natrix tessellata), including conspecific populations from the Aegean area. Our aim was to reconstruct their phylogeographical histories, especially regarding their occurrence on Crete. Location Crete, Aegean Sea and eastern Mediterranean. Methods Genetic diversity and relationships were based on sequences of the mitochondrial marker cytochrome b, applying phylogenetic analyses (maximum likelihood, Bayesian inference and neighbour-joining), a median-joining network analysis and a molecular dating analysis. Results The Z. situla phylogeny includes a clade with specimens from Crete, the Peloponnese and Thera, while specimens from Turkey, northern Greece and the eastern Aegean islands form a separate clade. The H. gemonensis tree also presents two clades: one comprising specimens from Crete and Kythera, and another representing the continental part of the species' distribution. For N. tessellata, Cretan populations are found as the sister clade to populations from Europe and western Turkey. A more complex genetic structure is found in T. fallax: specimens from Crete, Thera and Antikythera form a clade, which itself forms part of a ‘western’ clade, and an ‘eastern’ clade includes specimens from Turkey, the eastern Aegean islands and Cyprus. The splits resulting in the Cretan clades for T. fallax and N. tessellata occurred at the end of the Miocene and the Pliocene/Pleistocene boundary, respectively. The Cretan lineages of H. gemonensis and Z. situla diversified during the Pleistocene. Main conclusions Zamenis situla and H. gemonensis exhibit a phylogeographical pattern that involves a transmarine dispersal from southern continental Greece to Crete (possibly by humans in the case of Z. situla). The occurrence of T. fallax on Crete is explained by a natural dispersal from the west and isolation by vicariance. Although these two patterns have also been inferred for other studied herptiles of Crete, the pattern in N. tessellata is unique and involves a transmarine dispersal from south-western Turkey to Crete.