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In 1987, Cambridge University Press published a volume entitled Molecules and Morphology in Evolution: Conflict or Compromise? edited by the esteemed British palaeobiologist Colin Patterson. Since the 1980s, we have witnessed a great deal of incorporation of the tools and data of molecular biology into palaeontological hypothesis building and testing. The degree of integration is substantial enough so as to rule out the rather pejorative subtitle of the 1987 volume, ‘conflict or compromise’. We believe a new designation is appropriate: ‘synergy’. Stated differently, our ability to address major questions in biological history requires the integration of molecular methods and data into the palaeobiologist's toolkit. The antagonism implicit in the notion of ‘conflict or compromise’ is more an artefact of disciplinary boundaries and analytical traditions, and is not firmly rooted in the data of biology. Palaeobiologists today routinely consider data from molecular biology in their research on the shape and antiquity of the tree of life (‘divergence’), and in understanding the genetic and developmental mechanisms behind morphological change (‘mechanisms’). This book documents aspects of this synergy, focusing on these two general categories: divergence and mechanisms. It derives from the symposium ‘molecular tools in palaeobiology’ that took place during the 2009 meetings of the Society of Vertebrate Paleontology in Bristol, UK. In retrospect, we realize that the ‘vertebrate’ orientation of that conference has resulted in a level of taxonomic focus in this book that excludes many important contributions regarding evolutionary divergence and mechanisms. Nevertheless, this is no small taxonomic category, and there has been much to say about it since 1987.

List of contributors 1. Molecular tools in paleobiology: divergence and mechanisms Robert J. Asher and Johannes Muller Part I. Divergence: 2. Genomics and the lost world: paleontological insights into genome evolution Chris Organ 3. Rocking clocks and clocking rocks: a critical look at divergence time estimation in mammals Olaf R. P. Bininda-Emonds, Robin M. D. Beck and Ross D. E. MacPhee 4. Morphological largess: can morphology offer more and be modeled as a stochastic evolutionary process? Hans C. E. Larsson, T. Alexander Dececchi and Luke B. Harrison 5. Species selection in the molecular age Carl Simpson and Johannes Muller Part II. Mechanisms: 6. Reconstructing the molecular underpinnings of morphological diversification: a case study of the Triassic fish Saurichthys Leonhard Schmid 7. A molecular guide to regulation of morphological pattern in the vertebrate dentition and the evolution of dental development Moya Smith and Zerina Johanson 8. Molecular biology of the mammalian dentary: insights into how complex skeletal elements can be shaped during development and evolution Neal Anthwal and Abigail S. Tucker 9. Flexibility and constraint: patterning the axial skeleton in mammals Emily A. Buchholtz 10. Molecular determinants of marsupial limb integration and constraint Karen E. Sears, Carolyn K. Doroba, Xiaoyi Cao, Dan Xie and Sheng Zhong 11. A developmental basis for innovative evolution of the turtle shell Shigeru Kuratani and Hiroshi Nagashima 12. A molecular-morphological study of a peculiar limb morphology: the development and evolution of the mole's 'thumb' Christian Mitgutsch, Michael K. Richardson, Merijn A. G. de Bakker, Rafael Jimenez, Jose Ezequiel Martin, Peter Kondrashov and Marcelo R. Sanchez-Villagra 13. Manus horribilis: the chicken wing skeleton Michael K. Richardson Index.

The semicircular canals (SCs), part of the vestibular apparatus of the inner ear, are directly involved in the detection of angular motion of the head for maintaining balance, and exhibit adaptive patterns for locomotor behaviour. Consequently, they are generally believed to show low levels of intraspecific morphological variation, but few studies have investigated this assumption. On the basis of high-resolution computed tomography, we present here, to our knowledge, the first comprehensive study of the pattern of variation of the inner ear with a focus on Xenarthra. Our study demonstrates that extant three-toed sloths show a high level of morphological variation of the bony labyrinth of the inner ear. Especially, the variation in shape, relative size and angles of their SCs greatly differ from those of other, faster-moving taxa within Xenarthra and Placentalia in general. The unique pattern of variation in three-toed sloths suggests that a release of selection and/or constraints on their organ of balance is associated with the observed wide range of phenotypes. This release is coincident with their slow and infrequent locomotion and may be related, among other possible factors, to a reduced functional demand for a precise sensitivity to movement.

Previous analyses of how mammals vary in their ossification sequences have focused on monotremes, marsupials, and boreoeutherian placentals. Here, we focus on the sequence of cranial and postcranial ossification events during growth in the xenarthran skull and skeleton, including armadillos, anteaters, and sloths. We use two different methods to quantify sequence heterochrony: sequence analysis of variance (ANOVA) and event-paring/Parsimov. Our results indicate that Parsimov is conservative and does not detect clear heterochronic shifts between xenarthran and boreoeutherian placentals. Sequence-ANOVA performs better, but both methods exhibit sensitivity to the artifactual accumulation of ties. By controlling for ties and taking into account results that the methods have in common, our analysis suggests that xenarthrans significantly differ from other placentals by a late ossification of the sternum and an early ossification of the phalanges and pubis. We interpret these differences as showing that heterochrony plays a role in the skeletal development of xenarthrans, a change from previous studies that have emphasized the developmental homogeneity of the skeleton across placental mammals.

Background When simple sequence repeats are integrated into functional genes, they can potentially act as evolutionary ‘tuning knobs’, supplying abundant genetic variation with minimal risk of pleiotropic deleterious effects. The genetic basis of variation in facial shape and length represents a possible example of this phenomenon. Runt-related transcription factor 2 (RUNX2), which is involved in osteoblast differentiation, contains a functionally-important tandem repeat of glutamine and alanine amino acids. The ratio of glutamines to alanines (the QA ratio) in this protein seemingly influences the regulation of bone development. Notably, in domestic breeds of dog, and in carnivorans in general, the ratio of glutamines to alanines is strongly correlated with facial length. Results In this study we examine whether this correlation holds true across placental mammals, particularly those mammals for which facial length is highly variable and related to adaptive behavior and lifestyle (e.g., primates, afrotherians, xenarthrans). We obtained relative facial length measurements and RUNX2 sequences for 41 mammalian species representing 12 orders. Using both a phylogenetic generalized least squares model and a recently-developed Bayesian comparative method, we tested for a correlation between genetic and morphometric data while controlling for phylogeny, evolutionary rates, and divergence times. Non-carnivoran taxa generally had substantially lower glutamine-alanine ratios than carnivorans (primates and xenarthrans with means of 1.34 and 1.25, respectively, compared to a mean of 3.1 for carnivorans), and we found no correlation between RUNX2 sequence and face length across placental mammals. Conclusions Results of our diverse comparative phylogenetic analyses indicate that QA ratio does not consistently correlate with face length across the 41 mammalian taxa considered. Thus, although RUNX2 might function as a ‘tuning knob’ modifying face length in carnivorans, this relationship is not conserved across mammals in general.

Chromogranin A (CgA) is used as a generic tumor marker for neuroendocrine tumors. Proton pump inhibitors (PPI) are known to increase CgA, but it is not clear to what extent, and there is little information on how long PPI need to be discontinued before the effect of PPI has disappeared. Furthermore, is it not known whether this PPI effect is dependent on the CgA assay used.The aim of the study was to determine the effect of 7-d treatment with a PPI and its discontinuation on CgA in serum and plasma comparing four CgA assays.Seventeen healthy subjects took lansoprazole 30 mg at bedtime for 7 d, and blood samples for CgA were obtained at baseline, d 7 of PPI use, and 1, 2, 4, and 7 d after discontinuation of the PPI. In all samples, CgA was measured using the following assays: Alpco (serum and plasma), Cis-Bio (serum and plasma), DAKO, and Cis-Bio radioisotope assay.When using the same assay, CgA was higher in plasma than in serum. Treatment with a PPI for 1 wk resulted in a significant (about 2.5-fold) increase in CgA with significant interindividual variation. After discontinuation of PPI, serum CgA gradually declined, with a half-life of 4-5 d.Short-term PPI use results in a significant increase of CgA in serum and plasma, an effect that is largely independent of the assay used. PPI need to be discontinued for 2 wk to fully eliminate their effect on CgA. This effect of PPI needs to be considered when interpreting results of CgA measurements.

Exposure to perfluorooctane sulfonate (PFOS) may arise directly, from emission and exposure to PFOS itself, or indirectly via the environmental release and degradation of PFOS-precursors. Human serum enantiomer fractions (EFs) of 1m-PFOS have been shown to be nonracemic, suggesting that PFOS-precursors are a significant source of PFOS in humans, but little is known about the importance of PFOS-precursors in ecosystems. In the current work, concentrations of PFOS, perfluorooctane sulfonamide (PFOSA), PFOS isomer profiles, and EFs of 1m-PFOS were determined in Lake Ontario water, sediment, fishes and invertebrates. Concentrations of PFOS and PFOSA were highest in slimy sculpin and Diporeia, and concentrations of the two compounds were often correlated. 1m-PFOS was racemic in sediment, water, sculpin and rainbow smelt, but nonracemic in the top predator, lake trout, and all invertebrate species. Furthermore, EFs were correlated with the relative concentrations of PFOS and PFOSA in invertebrates. Overall, these empirical observations with a new analytical tool confirm previous suggestions that PFOS-precursors contribute to PFOS in the food web, likely via sediment. Implications are that future PFOS exposures in this ecosystem will be influenced by an in situ source, and that the apparent environmental behavior of PFOS (e.g., bioaccumulation potential) can be confounded by precursors.

Summary Background Methotrexate (MTX) is administered subcutaneously to Crohn's Disease (CD) patients. There are very few studies evaluating the use of oral (PO) MTX in CD. A drug and its pharmaceutical alternative are equivalent (bioequivalence) when the bioavailability of the alternative falls within 80–125% of the bioavailability of the standard (US Food and Drug Administration - FDA). Aim To compare the pharmacokinetic (PK) profiles of PO and subcutaneous (SC) MTX in CD patients to determine the bioequivalence of these two routes. Methods Eleven patients received a PO and an SC MTX dose (25 mg) separated by one week over a two-week interval. Blood samples were collected at specified times over a 24-h period for each patient on two separate days. MTX plasma levels were obtained using sensitive mass spectrometry. Areas under the curve (AUC) were compared between the two routes. Results The mean AUC values were 3375 ng/mL × h (PO MTX) and 3985 ng/mL × h (SC MTX). The mean AUC ratio (PO/SC) was 0.86 (0.62–1.08). This correlates with a relative PO bioavailability of 86% in comparison to SC. The 90% confidence interval for the mean AUC (PO/SC) ratio is (0.785, 0.929). There were no adverse events. Conclusions The mean MTX AUC (PO/SC) in these patients falls outside the 90% confidence interval for the bioequivalence limit. SC MTX is more bioavailable than PO MTX; however, the mean relative MTX bioavailability (PO/SC) nearly met the FDA bioequivalence standard and PO MTX could be proposed in responders who would prefer this route.

SUMMARYHumans are infected by 2 genetic assemblages (A and B) of Giardia duodenalis, a protozoan parasite that causes gastro-intestinal disease. Sub-assemblages AI, AII, BIII and BIV are commonly identified in human cases. Detection requires amplification of G. duodenalis loci. Subsequent DNA sequencing or restriction fragment length polymorphism (RFLP) identifies sub-assemblages but is expensive (DNA sequencing) or insensitive (RFLP). This study investigated a fluorescence-based detection method, using terminal-restriction fragment length polymorphism (T-RFLP) of the glutamate dehydrogenase gene to characterize human infections. Clinical samples (n=73), positive for Giardia were collected in New South Wales, Australia, and were used to evaluate T-RFLP detection. The accuracy and sensitivity of T-RFLP detection was established by comparison to DNA sequencing and RFLP. Sub-assemblage assignment by T-RFLP identified BIV as the common subtype in N.S.W cases, whilst AI, AII and BIII were also detected. When compared to DNA sequencing and RFLP, analysis by T-RFLP was a reliable and reproducible method. Automated fluorescent detection enabled accurate sizing of restriction fragments and provided a sensitive alternative to RFLP. Discrimination of sub-assemblages by T-RFLP was comparable to DNA sequencing, but was efficient and inexpensive. The protocol described here provides a rapid and sensitive diagnostic tool for routine sample screenings in epidemiological research.

Between my home and office, I’ve got a very good bike path. For the most part it takes me through farm fields, completely removed from any automotive competition. So listening to audio while biking does not, fortunately, greatly increase my risk of running into any traffic surprises. This has enabled me to listen to quite a few lectures and debates on the intersection of religion and science, the “controversy” surrounding intelligent design (ID), how some atheists view Charles Darwin as antagonistic to religion, and how certain theists view evolution as caustic to their beliefs. In one such debate, part of an ongoing podcast called Unbelievable produced in the United Kingdom by Premier Christian Media, an advocate of ID articulated his view that Darwinian evolution cannot “create information”: Randomness has never produced a single clump of information in the history of the universe. … Have we ever seen a new structure, or a single gene, come into existence by natural selection? I know of no empirical evidence, and I’ve been asking biologists for 10 years now.

One of the most powerful means by which scientific inquiry can confirm a hypothesis is the congruence of data from different sources toward a common answer. We’ve just reviewed above some of the comparative anatomy (the study of the skeleton, teeth, limbs, organs, etc. across animal groups) that biologists use to show how vertebrates share common ancestry. Monkeys and humans are closer to one another than either is to a galago, and these three in turn share more recent common ancestry among each other than any does with a kangaroo. All mammals are more closely related to one another than any is to a crocodile, and so on, reflecting the branching structure shown in Figure 3.1. This broad-scale theory of genealogical relations among animals was initially proposed on developmental and anatomical evidence. Now, we know that completely independent bodies of data from the fossil record and molecular biology have also lent support to this theory of interrelationships. The pattern of genealogical relationships shown in Figure 3.1 has been articulated by many biologists with substantial consistency, in some cases before and more frequently after publication of On the Origin of Species . Pre-Darwinian biologists such as the Swedish taxonomist Carl Linnaeus or the French anatomist Georges Cuvier did not have a robust causal mechanism, or process, to explain what they observed in terms of shared features across plants and animals, or pattern. Nonetheless, Linnaeus and Cuvier (and anti-Darwinists such as Richard Owen or Louis Agassiz) were perfectly capable of observing the pattern left behind by evolution. They knew that some animals resemble each other in many ways despite living in very different environments (such as seals and cats, or hippos and camels). While they did not understand the process behind these patterns of resemblance, non-Darwinian taxonomists were aware of the patterns and even incorporated them into their classifications.

From our time-bound perspective, humans are capable of observing only a snapshot of life. If the Darwin–Wallace theory is true that over time one species of organism has given rise to others (an idea known as “common ancestry”) via natural selection, then a full appreciation of species through time should reveal examples of animals that combine features from what we now categorize as other, distinct organisms. A different way of phrasing this very important concept is as follows: the features that we see defining certain animals (like the mother’s milk of mammals, the baleen of blue whales, the shells of turtles, or the feathers and beaks of birds) appear on the Tree of Life independently of any specific animal that we would recognize today because of those features. As a logical correlate of the common ancestry entailed in natural selection, the anatomical structure we recognize as “feather” has an independent origin relative to the first appearance of animals that anyone today would call “bird.” Relatedly, the common ancestry required by natural selection predicts that such animals (e.g., a feathered non-bird) possessed characters (e.g., teeth) that we associate with other groups. Such animals may be rightfully dubbed “intermediates” in the sense that they mix features we see as exclusive to animals that seem today to be well defined. No bird alive today lacks feathers or has teeth, just as no mammal alive today has more than a single bone in its jaw or lacks mother’s milk. But common ancestry predicts that this was not the case for all of the ancestors of birds or mammals, and that considerable uncertainty may therefore complicate the decision as to when the first “bird” or “mammal” first appeared in the fossil record.

Let us return to the predictions made by the theory of evolution by natural selection outlined in Chapter 2. One prediction we made arising from the occurrence of natural selection over time is that certain animals should mix adaptations and morphologies seen in others, comprising what are popularly known as “missing links,” or species that stretch the definition of exactly what constitutes a given category of organisms. In fact, as described for the coqui, platypus, bandicoot, and tarsier in Chapter 3, you don’t need fossils to observe suites of transitional features that link major animal groups. But of course we have them—lots of them—and to the unbiased observer they document the previous existence on Earth of an extraordinary array of life, now extinct. These fossils are in many cases representative of the common ancestors shared by major groups recognized today. You’ve heard of at least some of the most impressive fossils that enjoy the status of “missing link.” Starting with the letter “A,” you might recognize the names Acanthostega , Archaeopteryx , or Australopithecus . The list goes on (see Table 8.1)— Adapis , Aetiocetus , Apateon , Apternodus , Ardipithecus , Asioryctes —but most of these aren’t quite as famous. Archaeopteryx is probably the most famous fossil in the world. It’s a bird-like animal from the late Jurassic (about 150 million years ago) of southern Germany. Modern birds show feathers, powered flight, beaks, and lack tails and teeth. Archaeopteryx , in contrast, blurs the definition of “bird” because it combines features we associate with very different groups in one animal. It has the flight-adapted forelimbs and feathers of a bird, but the teeth, hip bones, and long tail of a lizard. For well over 100 years, up until a rash of discoveries in the 1990s–2000s, Archaeopteryx was one of only a few fossils that challenged our understanding of what a “bird” really is, anatomically speaking.

There are many cases in the fossil record of extinct species bridging the apparent anatomical gap between living groups, such as what we observed in the previous chapter between living mammals and the common ancestor we share with crocodiles, birds, lizards, and snakes. One of the other cases that we’ll look at in some detail concerns modern elephants, a group zoologically classified in the Order Proboscidea. At present, there are at least two and probably three species. African elephants belong in the genus Loxodonta and are most commonly grouped in the species L. africana . A smaller species of “forest elephant” has also been proposed, Loxodonta cyclotis . Both are distinct from the Asian elephant, Elephas maximus . These species comprise a minute fraction of the diversity of proboscideans that have existed over the past 60 million years.

I grew up in a conservative town in western New York state, about 350 miles northwest of Manhattan. During the early nineteenth century, the rural counties between Buffalo and Syracuse NY were known as the “burned over district” due to their revivalist religious zeal. Among the more famous evangelists of nineteenth-century New York state was Joseph Smith, founder of the Mormon Church. In terms of their more recent political history, western New Yorkers have sent such conservative Republicans as Tom Reynolds and Bill Paxon to represent them in the US Congress. In the US presidential elections of November 2008, several counties of western New York state gave the Republican ticket of John McCain and Sarah Palin a substantial majority, reaching close to 20 percentage points in some cases, compared to the national result in which Barack Obama won the popular vote by a “landslide” of 7%. Evangelical Christianity has a strong following in this part of the United States and played a very important role in my own youth. At present, I’m a full-time academic at an elite British university and I’ve paid taxes to two different European governments over the past decade. By all accounts, I should have little in common socio-politically with the people of my hometown, but the fact is I do. For example, like many of my western New York neighbors, I can’t stand the idea of voting for political candidates sympathetic to trial lawyers who have litigated the US health care system into the world’s most expensive and least efficient. A lot of the men and women in my hometown are proud of the fact that they served in the US military, and have tried to foster democracy in Iraq and Afghanistan. I’m proud of them too. Politics are not one-dimensional, and the stereotypical dichotomy of rural Republican versus ex-pat liberal does not trump the down-to-earth pragmatism that characterizes the part of the United States where I grew up.

We provide here unique data on elephant skeletal ontogeny. We focus on the sequence of cranial and post-cranial ossification events during growth in the African elephant (Loxodonta africana). Previous analyses on ossification sequences in mammals have focused on monotremes, marsupials, boreoeutherian and xenarthran placentals. Here, we add data on ossification sequences in an afrotherian. We use two different methods to quantify sequence heterochrony: the sequence method and event-paring/Parsimov. Compared with other placentals, elephants show late ossifications of the basicranium, manual and pedal phalanges, and early ossifications of the ischium and metacarpals. Moreover, ossification in elephants starts very early and progresses rapidly. Specifically, the elephant exhibits the same percentage of bones showing an ossification centre at the end of the first third of its gestation period as the mouse and hamster have close to birth. Elephants show a number of features of their ossification patterns that differ from those of other placental mammals. The pattern of the initiation of the ossification evident in the African elephant underscores a possible correlation between the timing of ossification onset and gestation time throughout mammals.

Results are presented for the long-term resolution of an ensemble of orbits similar to that of the high-inclination, intermediate-period asteroid 5335 Damocles (formerly 1991 DA). This body has a chaotic orbit that crosses the orbits of Mars, Jupiter, Saturn, and Uranus, but is relatively stable for several x10_4 yr either side of the present because the orientation does not allow close encounters with the two largest planets. The short-term evolution is dominated by mean-motion resonances with Jupiter leading to extended periods of almost constants semimajor axis, while secular pertubations and random close encounters with the major planets on time-scale greater x 10_4 yr cause occasional transition to orbits of small perihelion distance. There is substantial probability that the future orbit will cross that of the Earth, and Damocles may spend 25 per cent of its lifetime on such an orbit. Although Damocles has been classified as an asteroid, it seems likely to be an inactive cometary nucleus with dynamical characteristics typical of Halley-type comets. It is suggested that Damocles may be the first of the significant population of such bodies to be discovered which make a major contribution of the flux of Earth impactors.

The effects of low activities of the monomeric Al species, Al3+, Al(OH)2 + and Al(OH)2+, on the peanut/Bradyrhizobium symbiosis were examined in solution culture. In flowing solution culture, growth of the host plant was depressed at activities ≥5 μM. Neither shoot dry weight, root dry weight nor root length were inhibited by 3 μM Al, an activity which reduced nodule number by 70%. Low nodule number was compensated for, at this activity, by an increase in weight per nodule. In non-flowing solution culture of similar composition, survival of a streptomycin resistant mutant of Bradyrhizobium spp. NC92 in the bulk solution or in the rhizosphere of peanut roots was unaffected by 20 μM Al. The site of infection by Bradyrhizobium was examined by scanning electron microscopy. Lateral root axils of plants exposed to ≥2 μM Al did not display the rosette of multicellular root hairs which is characteristic in normal plants. The detrimental effects of Al on nodulation appear to be related to structural changes at the site of infection which are observed at Al activities too low to cause any depression in growth of the host plant, including root length, and at activities of Al which do not affect survival of the free-living Bradyrhizobium.

Magnesium applications (MgS04.7H20) to achieve 8 and 16 mmolc/cm3 of Mg (324 and 1284 kg of MgS04 ha-1) were made on one Ultisol from Australia Northeast to correct Mg deficiency in plants and to verify the optimum level of Mg to grow common bean (Phaseolus vulgaris L). Magnesium was applied together with lime, N, K, Cu, Zn, B, and Mo as calcium carbonate, ammonium nitrate, potassium phosphate, cupric and zinc sulphate, boric acid and sodium molybdate respectively a month before planting and P as phosphoric acid at the planting. The pH reached the equilibrium after six weeks of incubation. Higher electrical conductivity (EC) was observed in soil where Mg was applied to reach 8 mmolc/cm3 in the absence of common bean and 16 mmolc/cm3 when the plant was present. Higher plant height, leaf area, dry matter weight:leaf area ratio and nutrient concentrations were observed in plants cultivated in soils treated with Mg to reach 8 mmolc/cm3 and 16 mmolc/cm3 when the plant was present. The plant top P content was very low but N, Ca and Mg contents can be considered normal for the common bean. Made available in DSpace on 2013-03-22T23:30:27Z (GMT). No. of bitstreams: 1 Oliveira.pdf: 487966 bytes, checksum: 0699882b46c70499f9dd7b034b6d983d (MD5) Previous issue date: 2000-06-07

Hedges (2011) recently published a critique of our 2010 BMC Evolutionary Biology article (Asher and Helgen 2010) in which he expressed a preference for the name Afrosoricida Stanhope et al. 1998 to signify the mammalian clade of tenrecs (Tenrecidae) and golden moles (Chrysochloridae). He disagreed with what he claimed to be our rationale for preferring another name for this group, Tenrecoidea McDowell 1958. Here is his portrayal of our taxonomic philosophy: "[Asher & Helgen] suggested that strict priority be used as a criterion for high-level names and that such priority be based on group content rather than the procedure used for low-level taxa, anchored to constituent taxa. ... [They] have proposed a radical departure from convention" (Hedges 2011:67–68).

Giardia intestinalis is a protozoan parasite and a human pathogen. It is a leading cause of human diarrheal disease and a significant cause of morbidity worldwide. At the molecular level, G. intestinalis is a species complex, consisting of genetic assemblages (A to G) and sub-assemblage strains. The genotypes that cause human disease have been characterised to assemblages A and B, and include strains AI, AII, BIII and BIV. PCR amplification of diagnostic loci is used to genotype samples and is required to understand different transmission cycles within communities. A multi-locus approach is required for validation of Giardia genotyping and molecular diagnostic techniques that are efficient across numerous loci have not been established. This study evaluated several published protocols for the 18S small subunit ribosomal RNA (18S rRNA) and glutamate dehydrogenase genes (gdh) genes. Assays were compared using spiked faecal samples and by measuring the concentration of DNA generated following DNA extraction and PCR amplification. An optimal molecular method for G. intestinalis identification was established from direct DNA extraction of faecal material and GC-rich PCR chemistry. The protocol was applied to 50 clinical samples and produced PCR success rates of 90% and 94% at the 18S rRNA and gdh loci. Cyst concentration prior to DNA extraction was not necessary, and the optimal protocol was highly sensitive and an efficient method for testing clinical samples.

Patterns of vertebral variation across mammals have seldom been quantified, making it difficult to test hypotheses of covariation within the axial skeleton and mechanisms behind the high level of vertebral conservatism among mammals. We examined variation in vertebral counts within 42 species of mammals, representing monotremes, marsupials and major clades of placentals. These data show that xenarthrans and afrotherians have, on average, a high proportion of individuals with meristic deviations from species' median series counts. Monotremes, xenarthrans, afrotherians and primates show relatively high variation in thoracolumbar vertebral count. Among the clades sampled in our dataset, rodents are the least variable, with several species not showing any deviations from median vertebral counts, or vertebral anomalies such as asymmetric ribs or transitional vertebrae. Most mammals show significant correlations between sacral position and length of the rib cage; only a few show a correlation between sacral position and number of sternebrae. The former result is consistent with the hypothesis that adult axial skeletal structures patterned by distinct mesodermal tissues are modular and covary; the latter is not. Variable levels of correlation among these structures may indicate that the boundaries of prim/abaxial mesodermal precursors of the axial skeleton are not uniform across species. We do not find evidence for a higher frequency of vertebral anomalies in our sample of embryos or neonates than in post-natal individuals of any species, contrary to the hypothesis that stabilizing selection plays a major role in vertebral patterning.

Normal pods (containing seed) of groundnut (Arachis hypogaea L.) (cv. TMV-2) were successfully raised in darkened, aerated, nutrient solution, but not in the light. The onset of podding was evident 7 to 8 d after gynophores were submerged in the darkened nutrient solution. An examination of pods and submerged portions of gynophore surfaces by scanning electron microscopy showed the presence of two distinctly different protuberances: unicellular root-hair-like structures that first developed from epidermal cells of the gynophores and developing pods; and branched septate hairs that developed later from cells below the epidermal layer. The septate hairs became visible only after the epidermal and associated unicellular structures had been shed by the expanding gynophore and pods. Omission of Mn and Mg from the podding environment increased pod and seed weight, whilst omission of Zn reduced pod and seed weight.

We show that a statistically significant number of Earth-crossing asteroids are part of the Taurid Complex of interplanetary objects. We also identify another group which appears aligned with (2212) Hephaistos. In addition, we describe the kind of orbital evolution that such asteroids undergo and consider the implications for the history of these two complexes, which may have a common origin

The large asteroid/comet 5145 Pholus in the outer Solar system has an orbit which currently crosses Saturn, Uranus and Neptune. We numerically integrate 27 test particles with initial orbits similar to but distinct from the present orbit of Pholus forward over 800 000 yr. Many particles remain in the outer Solar system with slow orbital evolution, and another group is accelerated into long-period orbits with perihelia still in the outer planetary region, exceedingly slow evolution then following. However, a significant fraction (5 out of 27) attain orbits crossing Jupiter's path, or at least approaching that planet (i.e. q < 6 au), and much swifter evolution then occurs

Little is known about the primary effects of aluminum (Al) in reducing root growth. However, the sorption of Al by the root cell wall, particularly by calcium (Ca) pectate, has been suggested as being important in the expression of Al toxicity in plants. To overcome problems arising from the close proximity of root cell components that may react with Al, a synthetic Ca pectate membrane was prepared as a model system for Al studies. Solution containing 1 mM Ca (as CaCl2) was passed through the membrane, and the flow rate measured. Solution containing 29 μM Al (as AlCl3) and 1 mM Ca reduced solution flow rate by > 80% from c. 3.5 to c. 0.6 mL/min within 2 min, with a further slight decline over the next 4 min. The Al concentration in solution proximate to the inlet side of the membrane decreased to 15 μM within 10 min, and only 3 μM Al was measured in solution that had passed through the membrane. These results suggest that an important primary effect of toxic Al is a reduction in water movement in...

Extracellular processes, particularly the adsorption of aluminium (Al) by pectate in the cell wall, have been proposed as important in the expression of Al toxicity to plant roots. In vitro studies were conducted on the effects of Al concentration (generally ≤ 32 μM), calcium (Ca) concentration (0.05 to 10 mM) and pH (3.2 to 5.4) on Al sorption by Ca pectate. There was a rapid reaction between Al and Ca pectate, there being no difference in Al remaining in solution after reaction times of 1 to 16 min, and only a slight decrease after 24 h. Increased Al concentration in solution increased linearly the sorption of Al by Ca pectate, with 70 to 84% of the Al originally in solution sorbed with ≤32 μM Al. In contrast, Al sorption decreased with increased Ca concentration in solution, and as pH decreased from 5.4 to 3.2. Only ≤30% of the sorbed Al was desorbed after 1 h by 1 mM CaCl2, 10 mM CaCl2 or 1 mM HCl. The amount of Al desorbed increased with a desorption period of 5 h, particularly with 1 mM HCl. These studies suggest that Al sorbed by Ca pectate in root cell walls is in equilibrium with Al in solution, and that Al toxicity is associated with the strong binding between Al and Ca pectate external to the cytoplasm.

Background Drug misuse is an important clinical problem associated with a poorer outcome in patients who have a diagnosis of schizophrenia. Qualitative studies have rarely been used to elicit reasons for drug use in psychosis, but not in schizophrenia. Methods Seventeen people with a diagnosis of schizophrenia and who had used street drugs were interviewed and asked to describe, in narrative form, their street drug use from their early experiences to the present day. Grounded theory was used to analyse the transcripts. Results We identified five reasons for continuing street drug use. The reasons were: as an 'identity defining vocation', 'to belong to a peer group', due to 'hopelessness', because of 'beliefs about symptoms and how street drugs influence them' and viewing drugs as 'equivalent to taking psychotropic medication'. Street drugs were often used to reduce anxiety aroused by voice hearing. Some participants reported street drugs to focus their attention more on persecutory voices in the hope of outwitting their perceived persecutors. Conclusions It would be clinically useful to examine for the presence of the five factors in patients who have a diagnosis of schizophrenia and use street drugs, as this is likely to help the clinician to tailor management of substance misuse to the individual patient's beliefs.

An issue arising from recent progress in establishing the placental mammal Tree of Life concerns the nomenclature of high-level clades. Fortunately, there are now several well-supported clades among extant mammals that require unambiguous, stable names. Although the International Code of Zoological Nomenclature does not apply above the Linnean rank of family, and while consensus on the adoption of competing systems of nomenclature does not yet exist, there is a clear, historical basis upon which to arbitrate among competing names for high-level mammalian clades. Here, we recommend application of the principles of priority and stability, as laid down by G.G. Simpson in 1945, to discriminate among proposed names for high-level taxa. We apply these principles to specific cases among placental mammals with broad relevance for taxonomy, and close with particular emphasis on the Afrotherian family Tenrecidae. We conclude that no matter how reconstructions of the Tree of Life change in years to come, systematists should apply new names reluctantly, deferring to those already published and maximizing consistency with existing nomenclature.

Solution culture has been used extensively to determine the phytotoxic effects of trace metals. A review of the literature from 1975 to 2009 was carried out to evaluate the effects of As(V), Cd(II), Co(II), Cu(II), Hg(II), Mn(II), Ni(II), Pb(II), and Zn(II) on plants grown in solution. A total of 119 studies was selected using criteria that allowed a valid comparison of the results; reported toxic concentrations varied by five orders of magnitude. Across a range of plant species and experimental conditions, the phytotoxicity of the trace metals followed the trend (from most to least toxic): Pb approximately Hg >Cu >Cd approximately As >Co approximately Ni approximately Zn >Mn, with median toxic concentrations of (muM): 0.30 Pb, 0.47 Hg, 2.0 Cu, 5.0 Cd, 9.0 As, 17 Co, 19 Ni, 25 Zn, and 46 Mn. For phytotoxicity studies in solution culture, we suggest (i) plants should be grown in a dilute solution which mimics the soil solution, or that, at a minimum, contains Ca and B, (ii) solution pH should be monitored and reported (as should the concentrations of the trace metal of interest), (iii) assessment should be made of the influence of pH on solution composition and ion speciation, and (iv) both the period of exposure to the trace metal and the plant variable measured should be appropriate. Observing these criteria will potentially lead to reliable data on the relationship between growth depression and the concentration of the toxic metal in solution.

This annex presents resources and data sources relating to the assessment of the right to health and health care at the country level. The information presented include resources on lobbying and advocacy, health indicators and data sources, resources on treaties, and data sources of country profiles, international treaties, regional treaties and organizations.Keywords: health care; health movement; international treaties; right to health

The right to health should be understood as a right to the enjoyment of a variety of facilities and conditions which the state is responsible for providing as being necessary for the attainment and maintenance of good health. The World Health Organization (WHO) articulated the first specific international health and human rights provisions in the preamble to its Constitution. The main effect of a human rights approach to health is that it re-frames basic health needs as health rights. The principle of progressive realization is articulated in certain human rights treaties, such as International Covenant on Economic, Social and Cultural Rights (ICESCR) and Convention on the Rights of the Child (CRC), in relation to some of the obligations contained in them. Certain state obligations apply irrespective of adverse conditions such as severe shortage of economic resources. These are obligations of immediate effect, and are therefore known as immediate state obligations.Keywords: economic resources; human rights approach; ICESCR; right to Health; World Health Organization (WHO)

Freedom from discrimination is the key principle in international human rights law. As such, it is central to a human rights approach to health. The obligation to ensure non-discrimination is closely linked to the principle of equity, which implies that states must pay attention to all sectors of the population. Inequity and discrimination often lie at the root of low health status among the poor and otherwise vulnerable and disadvantaged groups. Gender-based discrimination, which is usually against women, is a worldwide cause of ill-health and a widespread cause of violations of the right to health. Patterns of gender discrimination vary widely between countries, societies and cultures, but there is a universal tendency for gender discrimination cumulatively to disadvantage the health status of women and girls.Keywords: discrimination; non-discrimination; vulnerable; women

Internationally recognised and legally binding human rights instruments impose many obligations affecting the right to health on governments that have ratified them. This chapter is an introduction to Part 3 of this book. This part focuses on the key standards for monitoring the right to health: the universal standards of immediate, including minimum core, obligations; the equitable distribution of resources; and the importance of nondiscrimination with special regard to the position of poor, vulnerable, or otherwise disadvantaged groups in the community, whose health is at greatest risk. Monitoring is essential for making the right to health a reality in the everyday lives of individuals and communities. Part 3 also describes certain tools and activities that NGOs can employ to promote the right to health and to monitor its implementation.Keywords: NGOs; right to health