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Aim: Variation in body size across animal species underlies most ecological and evolutionary processes shaping local- and large-scale patterns of biodiversity. For well over a century, climatic factors have been regarded as primary sources of natural selection on animal body size, and hypotheses such as Bergmann's rule (the increase of body size with decreasing temperature) have dominated discussions. However, evidence for consistent climatic effects, especially among ectotherms, remains equivocal. Here, we test a range of key hypotheses on climate-driven size evolution in squamate reptiles across several spatial and phylogenetic scales. \ud \ud Location: Global. \ud \ud Time period: Extant.\ud \ud Major taxa studied: Squamates (lizards and snakes).\ud \ud Methods: We quantified the role of temperature, precipitation, seasonality and net primary productivity as drivers of body mass across ca. 95% of extant squamate species (9,733 spp.). We ran spatial autoregressive models of phylogenetically corrected median mass per equal-area grid cell. We ran models globally, across separate continents and for major squamate clades independently. We also performed species-level analyses using phylogenetic generalized least square models and linear regressions of independent contrasts of sister species.\ud \ud Results: Our analyses failed to identify consistent spatial patterns in body size as a function of our climatic predictors. Nearly all continent- and family-level models differed from one another, and species-level models had low explanatory power. \ud \ud Main conclusions: The global distribution of body mass among living squamates varies independently from the variation in multiple components of climate. Our study, the largest in spatial and taxonomic scale conducted to date, reveals that there is little support for a universal, consistent mechanism of climate-driven size evolution within squamates.

Aim Small geographic ranges make species especially prone to extinction from anthropogenic disturbances or natural stochastic events. We assemble and analyse a comprehensive dataset of all the world's lizard species and identify the species with the smallest ranges—those known only from their type localities. We compare them to wide-ranging species to infer whether specific geographic regions or biological traits predispose species to have small ranges. Location Global. Methods We extensively surveyed museum collections, the primary literature and our own field records to identify all the species of lizards with a maximum linear geographic extent of

Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.

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.

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.

Management of protected species becomes increasingly complex when one protected population negatively affects another. This occurs along coastlines and in rivers and estuaries of the U.S. Pacific Northwest, where protected marine mammals prey on threatened and endangered Pacific salmonids Oncorhynchus spp. Over 9 years, we observed a growing aggregation of California sea lions Zalophus californianus and Steller sea lions Eumetopias jubatus preying upon adult Chinook salmon O. tshawytscha and steelhead O. mykiss at Bonneville Dam on the Columbia River. Both before and concurrent with the observation study, we monitored radio-tagged salmon at Bonneville Dam and during their upriver spawning migrations. Springtime sea lion abundance steadily increased from 2002 to 2010 and the aggregation formed earlier each winter. The principal prey species in winter were resident white sturgeon Acipenser transmontanus and migratory steelhead and then shifted to predominantly Chinook salmon when the spring run arr...

Nagy, Z. T., Glaw, F. & Vences, M. (2010) Systematics of the snake genera Stenophis and Lycodryas from Madagascar and the Comoros. —Zoologica Scripta, 39, 426–435. Arboreal snakes belonging to the pseudoxyrhophiine genus Stenophis inhabit Madagascar but despite their spectacular appearance, surprisingly little is known about their natural history and systematics. Nonetheless, a close phylogenetic affinity of the genera Stenophis and Lycodryas (the latter genus currently includes a single species from the Comoros) has been hypothesized. Based on recent molecular genetic data, however, the monophyly of Stenophis was challenged. This study aimed at a systematic analysis and taxonomic revision of the genera Stenophis and Lycodryas. On the basis of new molecular genetic and morphological data and analyses, we propose to accommodate these snakes in three monophyletic genera: Lycodryas, Phisalixella and Parastenophis, and to consider Stenophis as a junior synonym of Lycodryas. In the new generic arrangement, the genera can also be well distinguished by morphological characters. On the specific level, Phisalixella tulearensis is resurrected and indications of further, undescribed taxa are revealed.

Active site loops that are conserved across superfamilies of myosins, kinesins, and G proteins play key roles in allosteric coupling of NTP hydrolysis to interaction with track filaments or effector proteins. In this study, we investigated how the class-specific natural variation in the switch-2 active site loop contributes to the motor function of the intracellular transporter myosin-5. We used single-molecule, rapid kinetic and spectroscopic experiments and semiempirical quantum chemical simulations to show that the class-specific switch-2 structure including a tyrosine (Y439) in myosin-5 enables rapid processive translocation along actin filaments by facilitating Mg2+-dependent ADP release. Using wild-type control and Y439 point mutant myosin-5 proteins, we demonstrate that the translocation speed precisely correlates with the kinetics of nucleotide exchange. Switch-2 variants can thus be used to fine-tune translocation speed while maintaining high processivity. The class-specific variation of switch-2 in various NTPase superfamilies indicates its general role in the kinetic tuning of Mg2+-dependent nucleotide exchange.—Nagy, N.T., Sakamoto, T., Takács, B., Gyimesi, M., Hazai, E., Bikádi, Z., Sellers, J.R., Kovács, M. Functional adaptation of the switch-2 nucleotide sensor enables rapid processive translocation by myosin-5.

The pseudoxyrhophiine snake genus Liopholidophis Mocquard, 1904 is endemic to Madagascar and consists of two distinct species groups. We performed molecular phylogenetic analyses using nucleotide sequences of c. 2200 bp from two mitochondrial genes (16S rRNA, cyt b) and one nuclear gene (c-mos) to test the monophyly of the genus Liopholidophis and to investigate the relationships of the known species and an unidentified Liopholidophis population. Our phylogeny strongly supports the polyphyly of the genus Liopholidophis, confirms the monophyly of both species groups, and reveals that the unidentified population belongs to a new species. We therefore transfer the species of the former L. stumpffi group (L. epistibes, L. infrasignatus, L. lateralis, L. martae, and L. stumpffi) to a new genus Bibilava gen. n. and describe Liopholidophis dimorphus sp. n. from the rainforests of Montagne d’Ambre National Park in northern Madagascar. Finally, we compare our phylogeny with previous hypotheses and discuss the evolution of the extreme sexual dimorphism in tail length of Liopholidophis s. str.

Summary New 4-phenyl-1,2,3,4-tetrahydro-β-carbolines were synthesized from β-phenyltryptophan ester. They were evaluated in induced pain on rodents. Amide 17b proved to be the most powerful in the series. Several compounds display significative antiinflammatory properties.

The localization properties of the π-electron system of some aromatic and conjugated hydrocarbon molecules have been investigated. The π orbitals have been obtained using a standard PPP-SCF procedure. The shape analysis was carried out using the novel concept of the relation between the localization measure and structural entropy. According to our investigations the π-electron system of these aromatic molecules is more localized than expected. The eigenstates seem to show one-dimensional characteristics with a decay rate generally faster than exponential. Linear chains, on the other hand, have rather delocalized orbitals. As a byproduct we have found that in certain systems some states exhibit step-function–like behavior, similar to bond-centered charge density waves.

Purpose: An artifact typically seen in axial cone‐beam computed tomography(CBCT) reconstructions is a dark region or ‘black hole’ situated beneath the scan isocenter. We have traced the cause of the artifact to scattered radiation coming from the patient table. The artifact is most severe for offset‐detector scans and is especially significant in image‐guidedradiotherapy(IGRT) where patient tables have flat tops and are larger than those used for diagnostic radiology. To address this problem, we have developed a hybrid scatter kernel superposition (SKS) method designed to correct for scatter from both the object‐of‐interest and the patient table. Method and Materials: The proposed algorithm uses separate kernels to estimate scatter from the patient table and the object‐of‐interest. For each projection image, the location of the shadow cast by the patient table on the imager is determined. The region not shadowed by the table is processed using asymmetric kernels that best model scatter transport through body‐like objects. The patient table region is processed using a combination of the asymmetric kernels and slab‐derived symmetric kernels. The composition of these hybrid kernels is projection‐angle dependent. To test the algorithm, pelvis phantom and patient data were acquired using the Varian On‐Board Imager (OBI) and processed. Artifact intensities and HU accuracies were assessed. Results: The hybrid kernel algorithm produced substantially better scatter estimates than previous SKS methods. HU non‐uniformities in the pelvis phantom were reduced from 97HU to 29HU. In the in vivo scan, the black hole artifact was reduced by 128HU and anatomical details were made more visible. Conclusions:Radiotherapy patient tables can produce significant scatter‐related artifacts. The proposed hybrid SKS algorithm effectively addresses this problem. Scatter from both the object‐of‐interest and the patient table was accurately estimated, and image uniformity and HU accuracy were greatly improved. Employees of Varian Medical Systems.

Purpose: To characterize the CBCT performance of a new radiation therapy platform (Trilogy MX). Methods: An entirely new CBCT system has been developed for Trilogy MX. The new CBCT system differs from that of the On‐Board Imager® (OBI) in the use of a beam hardening filter, which reduces patient dose, and an improved reconstructor, which uses scatter correction algorithms to account for the x‐ray scatter caused by the cone‐beam geometry. Scans of Catphan® and electron density (Model 062A, CIRS) phantoms have been compared with OBI scans. Hounsfield unit (HU) accuracy was checked by changing the z scan length and the phantom diameters for pelvis (125kVp, 680mAs, 45cm dia.) acquisitions. The Catphan was imaged using doses ranging between 5–20mGy (CTDIw). Projections acquired using clinical OBI units were also reconstructed for comparison using the new reconstructor.Results: The new CBCT system has higher dose efficiency and higher HU accuracy. When the volume length is reduced from 160mm to 90mm or when the phantom diameter is reduced from 330mm to 180mm, the HU values measured for the same inserts differ by −190 to +80HU for OBI scans and by –60 to +50HU for Trilogy MX scans (for electron densities between 0.2 and 1.2). The contrast detectability of the 1% contrast objects in the Catphan phantom improves from 9mm to 4mm diameter when using the same CTDIwdose as OBI. Clinical images exhibit much better uniformity, elimination of streaks and better definition of the skin surface. Conclusions: The new reconstruction algorithm makes substantial improvements in CBCTimage quality, reduces patient dose and increases HU accuracy. The new system produces CBCTimages, which are much better suited to image guidance and which may be suitable for other tasks such as adaptive RT planning.

In vitro pretreatment with Met-Enk of human PMNLs obtained from patients suffering from type-2 diabetes mellitus resulted in the normalization of the ROS generating system. It is assumed that Met-Enk has a modulating effect on the arachidonic acid metabolism, with a consecutive increase of the LTB4 release.

A computer simulation of the kinetics of the amine salt initiated lactam polymerization was carried out using an extended kinetic model. In the reaction scheme the formation and relatively fast two-way reaction of a tetrahedral intermediate, as well as the role of the acid in its formation were incorporated. On the basis of the extended kinetic model the calculated lactam conversion and the concentration of N-terminal groups, respectively, have been found to be in good agreement with the experimental values for both the amine salt initiated and the hydrolytic lactam polymerization. The numerical values of rate and equilibrium constants are given.

Die Kinetik der hydrolytischen Lactampolymerisation mit verschiedenen Initiatoren wurde untersucht. Die experimentellen Ergebnisse wurden auf Grundlage eines Mechanismus, der die Bildung und die Reaktionen der Amidinverbindungen berucksichtigt, interpretiert. Ein kinetisches Modell wird vorgestellt. Die mit diesem Modell berechneten Werte werden mit eigenen messungen und Literaturdaten verglichen. Die Geschwindigkeits- und Gleichgewichtskonstanten werden abgeschatzt. Die mit diesen Konstanten berechneten Werte zeigen eine befriedigende Ubereinstimmung mit den experimentellen Werten und Literaturangaben. The kinetics of hydrolytic polymerization of e-caprolactam was investigated with various initiators. The experimental results are interpreted in terms of the reaction scheme proposed earlier, which takes into account the formation and reactions of amidin groups. A kinetic model is suggested and the rate and equilibrium constants were estimated. By variation of the parameters sufficient agreement between calculated values and measured or literature data was reached.