An improved method using densitometry for evaluating severity of laser photocoagulation induced CNV

Laser photocoagulation induced choroidal neovascularization currently is the most effective model available for the study of this disease in terms of efficacy of new drugs and therapies. Previously, evaluating the extent of choroidal neovascularization using this model was time- consuming and required the use of experienced personnel. We describe a new method for simple and rapid evaluation of laser induced choroidal neovascularization using densitometry. Fluorescein angiograms of a laser photocoagulated rat eye were scanned into a computer. Densitometry software subsequently was used to calculate the severity of the laser lesions. The densitometry method proved effective for calculating the extent of laser induced choroidal neovascularization. In addition, this method was more rapid than visual evaluations and less likely to produce errors.     

The radiation of Satyrini butterflies (Nymphalidae: Satyrinae): a challenge for phylogenetic methods

We have inferred the most comprehensive phylogenetic hypothesis to date of butterflies in the tribe Satyrini. In order to obtain a hypothesis of relationships, we used maximum parsimony and model‐based methods with 4435 bp of DNA sequences from mitochondrial and nuclear genes for 179 taxa (130 genera and eight out‐groups). We estimated dates of origin and diversification for major clades, and performed a biogeographic analysis using a dispersal–vicariance framework, in order to infer a scenario of the biogeographical history of the group. We found long‐branch taxa that affected the accuracy of all three methods. Moreover, different methods produced incongruent phylogenies. We found that Satyrini appeared around 42 Mya in either the Neotropical or the Eastern Palaearctic, Oriental, and/or Indo‐Australian regions, and underwent a quick radiation between 32 and 24 Mya, during which time most of its component subtribes originated. Several factors might have been important for the diversification of Satyrini: the ability to feed on grasses; early habitat shift into open, non‐forest habitats; and geographic bridges, which permitted dispersal over marine barriers, enabling the geographic expansions of ancestors to new environments that provided opportunities for geographic differentiation, and diversification.

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A spectacular new species of Nepenthes L. (Nepenthaceae) pitcher plant from central Palawan,Philippines

A new species of Nepenthes L., N. attenboroughii (Nepenthaceae), from Palawan Island in the Philippines, is described and illustrated. It is restricted to rocky, ultramafic soils that comprise the summit region of Mount Victoria, Municipality of Narra, where it occurs in isolation from other members of the genus. On the basis of the morphological features, this new taxon appears to be related to both N. mira Jebb & Cheek of Palawan and N. rajah Hook.f. of Borneo. Its substantial size places it among the largest of known pitcher plants. The diagnostic morphological characters are discussed and an updated key is provided for a revised complex of Nepenthes species from the Palawan and North Borneo phytogeographical region. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 195–202.     

Deconstructing Ixodes ricinus: a partial matrix model allowing mapping of tick development,mortality and activity rates

A stage‐structured Leslie matrix model of a partial, discrete population of Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) ticks was developed to elucidate the impact of climate trends on the distribution and phenology of this species in the western Palaearctic. The model calculates development and mortality rates for each instar and evaluates recruitment rates based on the development of the tick population. The model captures the changes in development and mortality rates, providing a coherent index of performance correlated with the tick's geographic range. Maximum development rates are recorded for latitudes south of 36 °N and are spatially correlated with sites of maximum temperature, highest saturation deficit and highest mortality. The maximum available developmental time (the total annual time during which temperature allows development) for I. ricinus in the western Palaearctic is < 45% of the total year. North of 60 °N, available developmental time decreases sharply to only 15% of the year. The latitudinal boundary at which survival rates sharply drop is 43–46 °N, clearly delimiting the classically recognized extent of the main tick populations. The pattern of activity for larval–nymphal synchrony shows a clear west–east pattern. The model demonstrates the impact of climate according to tick stage and geographic location, and provides a practical framework for testing how the tick's lifecycle is affected by climate change.     

Long‐proboscid brachyceran flies in Cretaceous amber (Diptera: Stratiomyomorpha: Zhangsolvidae)

The monophyletic family Zhangsolvidae comprises stout‐bodied brachyceran flies with a long proboscis and occurring only in the Cretaceous, originally known in shale from the Early Cretaceous Laiyang Formation (Fm.) in China (Zhangsolva Nagatomi & Yang), subsequently from limestones of the Early Cretaceous Crato Fm. of Brazil. Cratomyoides Wilkommen is synonymized with Cratomyia Mazzarolo & Amorim, both from the Crato Fm.; Cratomyiidae is synonymized with Zhangsolvidae. Two genera and three species of Zhangsolvidae are described: Buccinatormyia magnifica Arillo, Peñalver & Pérez‐de la Fuente, gen. et sp.n. and B. soplaensis Arillo, Peñalver & Pérez‐de la Fuente, sp.n. , in Albian amber from Las Peñosas Fm. in Spain; and Linguatormyia teletacta Grimaldi, gen. et sp.n. , in Upper Albian–Lower Cenomanian amber from Hukawng Valley in Myanmar. Buccinatormyia soplaensis and Linguatormyia teletacta are unique among all Brachycera, extant or extinct, by their remarkably long, flagellate antennae, about 1.6× the body length in the latter species. A phylogenetic analysis of 52 morphological characters for 35 taxa is presented, 11 taxa being Cretaceous species, which supports placement of the family within Stratiomyomorpha, although not to any particular family within the infraorder. This published work has been registered in Zoobank, http://zoobank.org/urn:lsid:zoobank.org:pub:F32CF887‐7C37‐45D5‐BD6B‐135FE9B729A7 .     

Distribution of streptothricin acetyltransferase encodi determinants among environmental bacteria

In this paper we report about a screening for streptothricin- (St)-resistant phenotypes and genotypes among environmental bacteria from a St virgin area. St-resistant bacteria were isolated from river water, sewage, manure and soil by selective plating. The resistance quotient was typical of an area without selective pressure. The occurrence of streptothricin acetyltransferase-encoding determinants and their localization on a Tn7-like transposon was tested by the application of a set of gene probes. Sat genes could be detected in 22.5% of the tested St-resistant bacteria but in 100% of the checked Enterobacteriaceae. However, we could not detect sat genes in St-resistant bacteria from soil samples. Surprisingly the sat genes were found to be located on conjugative or mobilizable plasmids for a rather high number of strains. The determined plasmid species and their restriction patterns showed a high degree of similarities to those observed from an area of strong selective pressure.     

Resolving UV Bioactinometric Results with Intensity and Time Distributions

A UV reactor with an annular design, a total liquid volume of 460[emsp4 ]ml, and outfitted with a single lamp with 1690[emsp4 ]mW of germicidal power was tested. Coliphage MS2 was used as a bioactinometer to measure the UV dose at a flow rate of 56.7[emsp4 ]ml/sec in water with a very low absorbance. The Beers Law coefficient was A₁₀0.003. The measured dose (MS2 bioactinometry) was 35.2±1.1[emsp4 ]mW-sec/cm².A retention time distribution was generated with a dye tracer study. The reactor was modeled as if flow was confined to ten equal volume paths existing as concentric rings around the lamp. The UV intensity along each path (ith intensity) was calculated to generate a simulated distribution of UV intensity in the reactor. The retention time distribution was subdivided to estimate the retention time associated with each decile jth time) of the total flow.Seven methods of associating the ith intensity with the jth retention time were used to produce simulated dose distributions for the reactor. The average UV dose for each distribution was calculated as the average of the products of I and t (AP protocol) and by the apparent survival (AS protocol), in which the predicted survival along each path was averaged to back-calculate dose from the reference batch inactivation curve. The average dose predicted assuming that time and intensity were independent was 51.5[emsp4 ]mW-sec/cm² based on the arithmetic average (AP protocol). Using the apparent survival method, the predicted dose for the independent distribution (I independent of t) was 36.4[emsp4 ]mW-sec/cm². Three methods of developing dependent structure between time and intensity were tested. In the best possible case for stratified flow (I negatively correlated with t) the calculated (AS) intensity was 46.3[emsp4 ]mW-sec/cm^2. In the worst case for stratified flow (I positively correlated with t) the AS intensity was 32.0[emsp4 ]mW-sec/cm². In a rational case where flows were assumed to be distributed parabolically (low flow at the wall and at the lamp) produced an AS intensity of 37.7[emsp4 ]mW-sec/cm². When either time or intensity was averaged, while the other variable was allowed to keep its distribution, the (AS) dose (time averaged 43.3[emsp4 ]mW-sec/cm², intensity averaged 41.0[emsp4 ]mW-sec/cm²), yielded a poor prediction compared to the measured value.The errors associated with averaging time, intensity, or both, far outweigh the errors associated with choosing a rational distribution or an independent distribution of time and intensity in the prediction. This observation is generally true whenever an organism is exposed to UV light in a flow through reactor such that the range of doses is within the portion of the inactivation curve exhibiting strong exponential decay.