New species of Laboulbenia (Laboulbeniales, Ascomycota) on Heteroptera (Hemiptera, Insecta) from South America.

Four new species of Laboulbenia are described, adding substantially to the known species recorded from Heteroptera hosts. Previously, only 12 species of Laboulbenia and only 96 of the approximate 2325 known species of Laboulbeniales have been recorded on the Heteroptera. The addition of these four new species of Laboulbenia, occurring on two genera within Veliidae, brings the total number to 100 species. These species are recorded on the genera Paravelia and Oiovelia collected from Brazil, Suriname, and Peru.

New species of Laboulbenia (Laboulbeniales, Ascomycota) on Gerridae (Hemiptera, Insecta), a new host family.

Four new species of Laboulbenia (Laboulbeniales, Ascomycota) occurring on Gerridae (Hemiptera, Insecta), a new host family, are described from six Central and South American countries: Bolivia, Brazil, Ecuador, Panama, Peru, and Venezuela. The new species are Laboulbenia brachymetrae, L. cylindrostethi, L. neogerris, and L. tachygerris.

Studies on Dimorphomyceteae: I. New species of Nycteromyces and Dimeromyces (Laboulbeniales) on bat flies (Streblidae).

Three new species, Nycteromyces orientalis, Dimeromyces capensis, and D. streblidarum, belonging to the Laboulbeniales (Fungi, Ascomycota) and collected on bat flies (Diptera, Streblidae), are described and illustrated. The new species of Nycteromyces is the second described in this rarely collected genus, with the type species, N. streblidinus, previously collected only three times from Venezuela, Panama, and Honduras. The material for our new species comes from Australia, India, Philippines, and Tanzania, and morphological characters of these new collections require emendation of the original generic diagnosis. The distribution of N. streblidinus is also extended with additional collections from Costa Rica and Peru. We describe two new species of Dimeromyces from streblid hosts, the first report of any members of this large, diverse genus on this host family. Newly described taxa are compared with known species and the genera Nycteromyces and Dimeromyces discussed in relation to other known Laboulbeniales taxa.

New species of Prolixandromyces (Laboulbeniales) from South America.

Four new species of Prolixandromyces (Laboulbeniales, Ascomycota) found on Veliidae (Heteroptera) from Bolivia, Brazil, Peru, and Venezuela are described and illustrated. These four species, Prolixandromyces anseris, P. tritici, P. blackwelliae, and P. bromelicola, represent the first records of this genus from South America, and their discovery requires emendation of the original generic circumscription. The newly described fungi are compared with known species, and a new key to identification is provided.

Molecular phylogeny of the Laboulbeniomycetes (Ascomycota).

A first molecular-based phylogeny is presented for the Laboulbeniomycetes, a group of ascomycete fungi that utilize arthropods for nutrition and/or dispersal. Morphological diversification and life-history evolution has made it difficult to resolve relationships within the group, and to identify close relatives. Here, we infer a preliminary phylogeny based on acquisition of 51 new SSU rDNA sequences, representing a total of 65 taxa. The results of this study demonstrate that Laboulbeniomycetes is monophyletic, and related to Sordariomycetes. The class could be divided into at least 4 or 5 orders, though we refrain from formally giving names to these at this stage. Further evidence for the occurrence of asexuality within the class is provided by the inclusion of the genera Chantransiopsis and Tetrameronycha, both known only as asexual taxa with thalli consisting of linearly superposed cells. The precise placement of the genus Herpomyces (Herpomycetaceae), on cockroaches, remains unresolved in our analysis, but lies outside of the main clade of sexually reproducing Laboulbeniales. There is good support for this latter grouping, comprising taxa that are found on both aquatic and terrestrial hosts. Within this large assemblage, we recognize 5 distinct clades (clades E, F, G, H, I). Relationships among the so-called "aquatic genera" (≡ Ceratomycetaceae + some Euceratomycetaceae and Zodiomyces) are poorly resolved in our analyses, accounting for 3 of these clades (E, F, G), with the remainder of the taxa (largely equivalent to Laboulbeniaceae) split into two major groupings (clades H, I). Across all taxa, antheridial characteristics, features on which the earliest classifications were based, are shown to be homoplastic. On the other hand, features of perithecial development show an overall trend towards reduction, and appear to be phylogenetically informative. Morphological characters are identified that support the dichotomy in the Laboulbeniaceae and subclades within the two major groupings are discussed further in light of information on thallus morphology, development, and host relationships.

An analysis of the attrition of drug candidates from four major pharmaceutical companies.

The pharmaceutical industry remains under huge pressure to address the high attrition rates in drug development. Attempts to reduce the number of efficacy- and safety-related failures by analysing possible links to the physicochemical properties of small-molecule drug candidates have been inconclusive because of the limited size of data sets from individual companies. Here, we describe the compilation and analysis of combined data on the attrition of drug candidates from AstraZeneca, Eli Lilly and Company, GlaxoSmithKline and Pfizer. The analysis reaffirms that control of physicochemical properties during compound optimization is beneficial in identifying compounds of candidate drug quality and indicates for the first time a link between the physicochemical properties of compounds and clinical failure due to safety issues. The results also suggest that further control of physicochemical properties is unlikely to have a significant effect on attrition rates and that additional work is required to address safety-related failures. Further cross-company collaborations will be crucial to future progress in this area.

Molecular analysis reveals two new dimorphic species of Hesperomyces (Ascomycota, Laboulbeniomycetes) parasitic on the ladybird Coleomegilla maculata (Coleoptera, Coccinellidae).

Four morphotypes of Hesperomyces (Ascomycota, Laboulbeniomycetes) were found on the ladybird Coleomegilla maculata (Coleoptera, Coccinellidae) from Costa Rica and Ecuador. Partial SSU and ITS rDNA sequence analysis revealed that these belong to two phylogenetic species, each with a pair of morphotypes displaying position specificity. Confirmation of dimorphism in Laboulbeniales highlights the need for a thorough systematic revision of species concepts within the order. The theory of 'position specificity' also needs to be revisited.

Biological response to nano-scale titanium dioxide (TiO2): role of particle dose, shape, and retention.

Titanium dioxide (TiO2) is one of the most widely used nanomaterials, valued for its highly refractive, photocatalytic, and pigmenting properties. TiO2 is also classified by the International Agency for Research on Cancer (IARC) as a possible human carcinogen. The objectives of this study were to (1) establish a lowest-observed-effect level (LOEL) for nano-scale TiO2, (2) determine TiO2 uptake in the lungs, and (3) estimate toxicity based on physicochemical properties and retention in the lungs. In vivo lung toxicity of nano-scale TiO2 using varying forms of well-characterized, highly dispersed TiO2 was assessed. Anatase/rutile P25 spheres (TiO2-P25), pure anatase spheres (TiO2-A), and anatase nanobelts (TiO2-NB) were tested. To determine the effects of dose and particle characteristics, male Sprague-Dawley rats were administered TiO2 (0, 20, 70, or 200 µg) via intratracheal instillation. Bronchoalveolar lavage fluid (BALF) and lung tissue were obtained for analysis 1 and 7 d post exposure. Despite abundant TiO2 inclusions in all exposed animals, only TiO2-NB displayed any significant degree of inflammation seen in BALF at the 1-d time point. This inflammation resolved by 7 d, although TiO2 particles had not cleared from alveolar macrophages recovered from the lung. Histological examination showed TiO2-NB produced cellular changes at d 1 that were still evident at d 7. Data indicate TiO2-NB is the most inflammatory with a LOEL of 200 µg at 1 d post instillation.

Position specificity in Chitonomyces (Ascomycota, Laboulbeniomycetes) on Laccophilus (Coleoptera, Dytiscidae): a molecular approach resolves a century-old debate.

The occurrence of Laboulbeniomycete species consistently on a precise portion of beetle integument was investigated in 13 species of Chitonomyces ectoparasitic on the aquatic diving beetle Laccophilus maculosus (Coleoptera, Dytiscidae). The phenomenon was called "position specificity" by Roland Thaxter in 1896, yet the mechanism has remained unknown. By using molecular analysis of the nucSSU rRNA gene and the 5.8S and partial ITS1 rRNA regions, 13 species of Chitonomyces reported to exhibit position specificity on Laccophilus maculosus were placed neatly into pairs of morphotypes, resulting in synonomies and recognition of six phylogenetic species (one species is a triplet). Each phylogenetic species was located at corresponding positions on male and female beetles that make contact during mating. In addition, ecological data and video footage of the mating behaviors of Laccophilus confirmed that sexual transmission is the mechanism behind this enigmatic phenomenon.

Titanium dioxide nanoparticles in food and personal care products.

Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system and, subsequently, enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO(2), and discusses the impact of the nanoscale fraction of TiO(2) entering the environment. The foods with the highest content of TiO(2) included candies, sweets, and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 µg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 µg Ti/mg) to a high of 0.014 µg Ti/mg. Electron microscopy and stability testing of food-grade TiO(2) (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 µm pores. Two white paints contained 110 µg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 µg Ti/mg). This research showed that, while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to wastewater treatment plants (WWTPs) deserves attention. A Monte Carlo human exposure analysis to TiO(2) through foods identified children as having the highest exposures because TiO(2) content of sweets is higher than other food products and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium-based white pigment used annually, testing should focus on food-grade TiO(2) (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).

New species of Stigmatomyces from Asia.

Four new species of Stigmatomyces (Ascomycota, Laboulbeniomycetes, Stigmatomycetinae) parasitic on flies (Diptera) are described. These are S. aphaniosomae, parasitic on an undescribed species of Aphaniosoma (Chyromyidae) from Jordan; S. deemingii, parasitic on Milichia pubescens (Milichiidae) from Yemen; S. macanus, parasitic on Phortica spp. (Drosophilidae) from Taiwan; and S. mosilli, parasitic on Mosillus subsultans (Ephydridae) from Pakistan. Chyromyidae is a new host family for Laboulbeniales, and S. aphaniosomae is the first of the Laboulbeniales to be reported from Jordan.

Using prevalence indices to aid interpretation and comparison of agreement ratings between two or more observers.

Veterinary clinical and epidemiological investigations demand observer reliability. Kappa (κ) statistics are often used to adjust the observed percentage agreement according to that expected by chance. In highly homogenous populations, κ ratings can be poor, despite percentage agreements being high, because the probability of chance agreement is also high. Veterinary researchers are often unsure how to interpret these ambiguous results. It is suggested that prevalence indices (PIs), reflecting the homogeneity of the sample, should be reported alongside percentage agreements and κ values. Here, a published PI calculation is extended, permitting extrapolation to situations involving three or more observers. A process is proposed for classifying results into those that do and do not attain clinically useful ratings, and those tested on excessively homogenous populations and which are therefore inconclusive. Pre-selection of balanced populations, or adjustment of scoring thresholds, can help reduce population homogeneity. Reporting PIs in observer reliability studies in veterinary science and other disciplines enables reliability to be interpreted usefully and allows results to be compared between studies.

Tool use by wild New Caledonian crows Corvus moneduloides at natural foraging sites.

New Caledonian crows Corvus moneduloides use tools made from sticks or leaf stems to 'fish' woodboring beetle larvae from their burrows in decaying wood. Previous research on this behaviour has been confined to baited sites, leaving its ecological context and significance virtually unexplored. To obtain detailed observations of natural, undisturbed tool use, we deployed motion-triggered video cameras at seven larva-fishing sites. From 1797 camera hours of surveillance over 111 days, we recorded 317 site visits by at least 14 individual crows. Tool use was observed during 150 site visits. Our video footage revealed notable variation in foraging success among identifiable crows. Two nutritionally independent, immature crows spent considerable time using tools, but were much less successful than local adults, highlighting the potential role of individual and social learning in the acquisition of tool-use proficiency. During systematic surveys of larva-fishing sites, we collected 193 tools that crows had left inserted in larva burrows. Comparing these tools with the holes in which they were found, and with raw materials available around logs, provides evidence for tool selectivity by New Caledonian crows under natural conditions. Taken together, these two complementary lines of investigation provide, to our knowledge, the first quantitative description of larva fishing by wild crows in its full ecological context.

Cognitive processes associated with sequential tool use in New Caledonian crows.

BACKGROUND: Using tools to act on non-food objects--for example, to make other tools--is considered to be a hallmark of human intelligence, and may have been a crucial step in our evolution. One form of this behaviour, 'sequential tool use', has been observed in a number of non-human primates and even in one bird, the New Caledonian crow (Corvus moneduloides). While sequential tool use has often been interpreted as evidence for advanced cognitive abilities, such as planning and analogical reasoning, the behaviour itself can be underpinned by a range of different cognitive mechanisms, which have never been explicitly examined. Here, we present experiments that not only demonstrate new tool-using capabilities in New Caledonian crows, but allow examination of the extent to which crows understand the physical interactions involved. METHODOLOGY/PRINCIPAL FINDINGS: In two experiments, we tested seven captive New Caledonian crows in six tasks requiring the use of up to three different tools in a sequence to retrieve food. Our study incorporated several novel features: (i) we tested crows on a three-tool problem (subjects were required to use a tool to retrieve a second tool, then use the second tool to retrieve a third one, and finally use the third one to reach for food); (ii) we presented tasks of different complexity in random rather than progressive order; (iii) we included a number of control conditions to test whether tool retrieval was goal-directed; and (iv) we manipulated the subjects' pre-testing experience. Five subjects successfully used tools in a sequence (four from their first trial), and four subjects repeatedly solved the three-tool condition. Sequential tool use did not require, but was enhanced by, pre-training on each element in the sequence ('chaining'), an explanation that could not be ruled out in earlier studies. By analyzing tool choice, tool swapping and improvement over time, we show that successful subjects did not use a random probing strategy. However, we find no firm evidence to support previous claims that sequential tool use demonstrates analogical reasoning or human-like planning. CONCLUSIONS/SIGNIFICANCE: While the ability of subjects to use three tools in sequence reveals a competence beyond that observed in any other species, our study also emphasises the importance of parsimony in comparative cognitive science: seemingly intelligent behaviour can be achieved without the involvement of high-level mental faculties, and detailed analyses are necessary before accepting claims for complex cognitive abilities.

Video cameras on wild birds.

New Caledonian crows (Corvus moneduloides) are renowned for using tools for extractive foraging, but the ecological context of this unusual behavior is largely unknown. We developed miniaturized, animal-borne video cameras to record the undisturbed behavior and foraging ecology of wild, free-ranging crows. Our video recordings enabled an estimate of the species' natural foraging efficiency and revealed that tool use, and choice of tool materials, are more diverse than previously thought. Video tracking has potential for studying the behavior and ecology of many other bird species that are shy or live in inaccessible habitats.

New species of Corethromyces from South America.

Three new species of Corethromyces (Ascomycetes, Laboulbeniales, Stigmatomycetinae) parasitic on South American Staphylinidae (Insecta Coleoptera) are described. These are C. aequatorialis, parasitic on Gnathymenus sp. from Ecuador, C. otongaensis, parasitic on Biocrypta sp. from Ecuador, and C. thayerae, parasitic on Medon obscuriventer from Chile.

New species of Stigmatomyces from various continents.

Four new species of Stigmatomyces (Ascomycetes, Laboulbeniales, Stigmatomycetinae) parasitic on flies (Diptera) are described. These are S. benjaminii, parasitic on Spilochroa polita (Trixoscelididae) from Mexico, S. munarii, parasitic on Trixoscelis namibensis (Trixoscelididae) from Namibia, S. neurochaetae parasitic on Neurochaeta parviceps (Neurochaetidae) from Malaysia, and S. zaleae, parasitic on Zalea spp. (Tethinidae) from Australia. Both Trixoscelididae and Neurochaetidae are new host families for Laboulbeniales.

A New Caledonian crow (Corvus moneduloides) creatively re-designs tools by bending or unbending aluminium strips.

Previous observations of a New Caledonian crow (Corvus moneduloides) spontaneously bending wire and using it as a hook [Weir et al. (2002) Science 297:981] have prompted questions about the extent to which these animals 'understand' the physical causality involved in how hooks work and how to make them. To approach this issue we examine how the same subject ("Betty") performed in three experiments with novel material, which needed to be either bent or unbent in order to function to retrieve food. These tasks exclude the possibility of success by repetition of patterns of movement similar to those employed before. Betty quickly developed novel techniques to bend the material, and appropriately modified it on four of five trials when unbending was required. She did not mechanically apply a previously learned set of movements to the new situations, and instead sought new solutions to each problem. However, the details of her behaviour preclude concluding definitely that she understood and planned her actions: in some cases she probed with the unmodified tools before modifying them, or attempted to use the unmodified (unsuitable) end of the tool after modification. Gauging New Caledonian crows' level of understanding is not yet possible, but the observed behaviour is consistent with a partial understanding of physical tasks at a level that exceeds that previously attained by any other non-human subject, including apes.

Behavioural ecology: tool manufacture by naive juvenile crows.

New Caledonian crows (Corvus moneduloides) are the most prolific avian tool-users. Regional variation in the shape of their tools may be the result of cumulative cultural evolution--a phenomenon considered to be a hallmark of human culture. Here we show that hand-raised juvenile New Caledonian crows spontaneously manufacture and use tools, without any contact with adults of their species or any prior demonstration by humans. Our finding is a crucial step towards producing informed models of cultural transmission in this species, and in animals in general.

Lateralization of tool use in New Caledonian crows (Corvus moneduloides).

We studied laterality of tool use in 10 captive New Caledonian (NC) crows (Corvus moneduloides). All subjects showed near-exclusive individual laterality, but there was no overall bias in either direction (five were left-lateralized and five were right-lateralized). This is consistent with results in non-human primates, which show strong individual lateralization for tool use (but not for other activities), and also with observations of four wild NC crows by Rutledge & Hunt. Jointly, these results contrast with observations that the crows have a population-level bias for manufacturing tools from the left edges of Pandanus sp. leaves, and suggest that the manufacture and use of tools in this species may have different neural underpinnings.