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Summary The potato Rx gene provides resistance against Pepino mosaic virus (PepMV) in tomato; however, recent work has suggested that the resistance conferred may not be durable. Resistance breaking can probably be attributed to multiple mutations observed to accumulate in the capsid protein (CP) region of resistance-breaking isolates, but this has not been confirmed through directed manipulation of an infectious PepMV clone. The present work describes the introduction of two specific mutations, A-T78 and A-T114, into the coat protein minimal elicitor region of an Rx-controlled PepMV isolate of the EU genotype. Enzyme-linked immunosorbent assay (ELISA) and phenotypic evaluation were conducted in three Rx-expressing and wild-type solanaceous hosts: Nicotiana benthamiana, Nicotiana tabacum and Solanum lycopersicum. Mutation A-T78 alone was sufficient to confer Rx-breaking activity in N. benthamiana and S. lycopersicum, whereas mutation A-T114 was found to be associated, in most cases, with a secondary A-D100 mutation to break Rx-mediated resistance in S. lycopersicum. These results suggest that the need for a second, fitness-restoring mutation may be dependent on the PepMV mutant under consideration. Both mutations conferred Rx breaking in S. lycopersicum, whereas neither conferred Rx breaking in N. tabacum and only A-T78 allowed Rx breaking in N. benthamiana, suggesting that Rx may function in a different manner depending on the genetic background in which it is present.

Summary Pepino mosaic virus (PepMV) poses a worldwide threat to the tomato industry. Considerable differences at the genetic level allow for the distinction of four main genotypic clusters; however, the basis of the phenotypic outcome is difficult to elucidate. This work reports the generation of wild-type PepMV infectious clones of both EU (mild) and CH2 (aggressive) genotypes, from which chimeric infectious clones were created. Phenotypic analysis in three solanaceous hosts, Nicotiana benthamiana, Datura stramonium and Solanum lycopersicum, indicated that a PepMV pathogenicity determinant mapped to the 3′-terminal region of the genome. Increased aggression was only observed in N. benthamiana, showing that this factor is host specific. The determinant was localized to amino acids 11–26 of the N-terminal coat protein (CP) region; this is the first report of this region functioning as a virulence factor in PepMV.

This study sought to examine the factors affecting the acceptance of an entertainment medium, particularly online games, by expanding the technology acceptance model. To measure factors affecting the acceptance of online games, we fielded a survey with 244 gamers serving as respondents. Perceived usefulness, enjoyment, and economic value were found to have a positive influence on attitude toward gaming, whereas perceived ease of use was not a significant predictor. In addition, we found that gender and game type (multiplayer or not) showed differing patterns of results. Interestingly, perceptions of mass acceptance of gaming were found to have a negative effect on attitude toward online games. Theoretical and practical implications of these findings are discussed.

Crustaceans in the order Spinicaudata display a broad range of reproductive strategies, ranging from pure hermaphroditism to pure dioecy (separate males and females), and intermediate combinations. One particularly interesting genus of these “clam shrimps” is Eulimnadia. Based on offspring sex ratios, it has been suggested that all members of the genus are androdioecious: populations consist of mixtures of males and hermaphrodites. However, only two of the ~40 species in this genus have been examined histologically to confirm the presence of ovotestes in the purported hermaphrodites of this group. Here, we report both sex ratio and histological evidence showing that populations of five additional Eulimnadia species from India and Thailand are indeed mixes of males and hermaphrodites (four species) or hermaphrodite only (one species). Sex ratios of adults and offspring from isolated hermaphrodites are in accordance with those previously reported for 15 Eulimnadia species, and histological assays of four of the five species show the presence of both testicular and ovarian tissue in these hermaphrodites. As has been previously reported, the testicular tissue in members of these Eulimnadia spp. is located in a small section at the distal end of the gonad. In addition, the sperm produced in these hermaphrodites forms distinct plaques of compacted chromatin. Overall, these data are consistent with a single origin of hermaphroditism in Eulimnadia, and support the notion that all members of the genus are either androdioecious or all-hermaphroditic.

While mood has been found to affect brand extension evaluations, the specific mechanisms by which it affects those evaluations remain largely untested. This study suggests that mood-induced differences in cognitive processing style (relational vs. item-specific elaboration) are possible explanations affecting brand extension evaluations. Results of two experiments showed that consumers in a positive (vs. negative) mood engaged in relational (vs. item-specific) elaboration and consequently evaluated brand extensions and brand extension fit more favorably than consumers in a negative mood. The effects were found immediately after exposure (Experiment 1) and after a one-week delay (Experiment 2). Theoretical and practical implications are discussed. © 2011 Wiley Periodicals, Inc.

Focusing on the criminal law, I discuss three ways in which analytical philosophers might contribute to the development or health of the law (and of legal theory). The first is as humble under-labourers, who seek only to clarify legal rules and doctrines, but not to criticise them. This modest conception of the role of philosophy, however, proves to be untenable: clarification must become rational reconstruction - an attempt to make rational sense of the law; and rational reconstruction must involve at least an internal critique, which appraises the law in terms of ends, values or principles that the reconstruction discovers within the law. Such an internal critique must then also point beyond itself, to an external critique that appraises law in terms of the broader and deeper political and moral values by which states should be structured; the paper ends by noting some of the problems that such an external critique faces, and some of the problems that philosophers must face in trying to engage with the world of public policy.

The argument of this article is that we should understand probation as a mode of punishment: not as the kind of ‘merely punitive’ punishment which is all too familiar in our existing penal systems, but as a mode of constructive punishment which seeks to bring offenders to face up to the effects and implications of their crimes, to rehabilitate them, and to secure the kinds of goal — reparation and reconciliation — that are emphasised by advocates of restorative justice. To support this argument, I sketch a conception of punishment as a communicative enterprise in which probation officers would play a crucial role — not merely in administering sentences, but as mediators between offenders, victims and the wider community.

In response to Lawrence Solum's advocacy of a ‘virtue–centred theory of judging’, I argue that there is indeed important work to be done in identifying and characterising those qualities of character that constitute judicial virtues – those qualities that a person needs if she is to judge well (though I criticise Solum's account of one of the five pairs of judicial vices and virtues that he identifies – avarice and temperance). However, Solum's more ambitious claims – that a judge's vice necessarily corrupts her decisions, and that in at least some contexts we must define a legally correct decision as one that would be reached by a virtuous judge – should be rejected: we can undermine the former by attending to the requirements of due process, and the latter by attending to the ways in which a judge would try to justify her decision.

Nigel Walker’s first principle of criminalization declares that ‘Prohibitions should not be included in the criminal law for the sole purpose of ensuring that breaches of them are visited with retributive punishment’. I argue that we should reject this principle, for ‘mala prohibita’ as well as for ‘mala in se’: conduct should be criminalized in order to ensure (as far as we reasonably can) that those who engage in it receive retributive punishment. In the course of the argument, I show why we should not see the criminal law as consisting in ‘prohibitions’; I explain different species of mala prohibita, and show how their commission does involve genuine wrongdoing; and I show the importance of distinguishing the question of regulation from that of sanction.

Phylogenetic relationships among embryophytes (tracheophytes, mosses, liverworts, and hornworts) were examined using 21 newly generated mitochondrial small-subunit (19S) rDNA sequences. The "core" 19S rDNA contained more phylogenetically informative sites and lower homoplasy than either nuclear 18S or plastid 16S rDNA. Results of phylogenetic analyses using parsimony (MP) and likelihood (ML) were generally congruent. Using MP, two trees were obtained that resolved either liverworts or hornworts as the basal land plant clade. The optimal ML tree showed hornworts as basal. That topology was not statistically different from the two MP trees, thus both appear to be equally viable evolutionary hypotheses. High bootstrap support was obtained for the majority of higher level embryophyte clades named in a recent morphologically based classification, e.g., Tracheophyta, Euphyllophytina, Lycophytina, and Spermatophytata. Strong support was also obtained for the following monophyletic groups: hornworts, liverworts, mosses, lycopsids, leptosporangiate and eusporangiate ferns, gymnosperms and angiosperms. This molecular analysis supported a sister relationship between Equisetum and leptosporangiate ferns and a monophyletic gymnosperms sister to angiosperms. The topologies of deeper clades were affected by taxon inclusion (particularly hornworts) as demonstrated by jackknife analyses. This study represents the first use of mitochondrial 19S rDNA for phylogenetic purposes and it appears well-suited for examining intermediate to deep evolutionary relationships among embryophytes.

Thirteen polymorphic microsatellite loci were isolated and characterized from the clam shrimp Eulimnadia texana . In analyses of 20–50 individuals from two populations the number of alleles ranged from two to seven with observed heterozygosity ranging between 0.00 and 0.37. The low values for heterozygosity were not unexpected for a group characterized by its unusual androdioecious mating system, in which males compete with self-compatible hermaphrodites for offspring production. These microsatellites are likely to be useful for further evolutionary investigations of this rare mating system in these crustaceans.

In three adult dogs the cranial cruciate ligament of the right stifle was sectioned. The animals were examined at regular intervals over the following twenty-nine months and the clinical findings noted. Fluorochrome bone markers were injected at intervals of approximately six months. Following injection of barium sulphate and Berlin blue after euthanasia, the joint tissues of both stifles were examined for evidence of degenerative changes. The right stifles showed typical changes of osteoarthritis, while the left stifles revealed no abnormality.

Summary The decomposition of silicate minerals and related substances by fungi has been investigated using two techniques: (a) the incorporation of the mineral material in agar medium, when its breakdown is indicated by the formation of clear zones round the fungal growth; (b) the determination of the metal and silicate ions, derived from the insoluble materials and brought into solution as a result of fungal activity in liquid medium. Strains of fungi which produced citric and/or oxalic acid proved to be effective in decomposing certain natural silicates, while an oxalic acid-producing strain also released metallic ions and silica from rocks and soils. A possible role of fungi in biological weathering is discussed.

Procedures are described which have been in use for several years in a bottle plant for the purpose of making daily determinations of glass density as a check on glass composition. These procedures are examined experimentally with a view to adopting any changes in technique, such as those suggested by Knight and others, which will yield results more quickly. This study includes (1) a comparison of alternate methods of observing sink-float temperatures as to precision and time required, (2) determination of the effect of handling and marking samples, (3) an estimate of the variability introduced into density results by the use of samples from commercially annealed bottles, (4) a comparison of the amount and type of information which may be expected from various plans of sampling plant production, and (5) data on the reliability for use in glass-composition control of rod samples taken from forehearths, troughs, or tap streams. The use of rod samples, prepared “as described” and without reannealing, is recommended in composition-control work because (1) rod samples show less variability in the effect of thermal history on density than do those from lehr-annealed bottles from a number of lehrs, (2) elapsed time between entry of batch into the furnace and the completion of density determinations on glass made therefrom is approximately three hours less than when lehr-annealed bottle samples are used and approximately six hours less than when* reannealed samples from bottles are used, and (3) rod samples are available regardless of whether or not finished ware is being produced.

Summary A study has been made of the incidence of polysaccharide-producing bacteria in the root region of the grass strains Ryegrass (Lolium perenne) strain 823, Cocksfoot (Dactylis glomerata) strain S143, and Timothy (Phleum pratense) strain S50. The root surfaces of the three grasses had the highest percentage of isolates capable of producing capsule and/or slime material (particularly the latter) when compared with the rhizosphere soil and non-rhizosphere soil. Infra-red and paper chromatographic analyses of the extracellular material showed that the ability to produce fructosans was commoner in isolates from the root surface.

Hydrolysates of the soluble polysaccharide fraction from a well decomposed peat contained small amounts of 4-O-methyl-D-galactose and 2-O-methyl-L-rhamnose. the first-named sugar has not hitherto been isolated from natural sources. Its isolation supports a connexion between the occurrence of methylated sugars in Nature and the position of the linkage in related polysaccharides. the sugars were isolated from the complex mixture by gradient elution from Ultrasorb charcoal followed by partition chromatography on Celite columns with a butanol-light petroleum solvent. The significance of the occurrence of these sugars is discussed. It is suggested that the stability of the polysaccharides in soil may be associated with the presence of the methylated sugar units.

Creep of polycrystalline MgO was studied using four-point transverse bending at 1380° to 1800°K and stresses from 1000 to 5000 psi. The effects of temperature, stress, and grain size on the creep rate were determined for grain sizes from 2 to 20μ. Activation energies for creep decreased sharply with increasing grain size from 96,000 cal/mole at 2μ to 54,100 cal/mole at 5.5μ and then remained constant over the grain-size range 5.5 to 20μ. Creep was attributed in part to a stress-directed diffusional mechanism controlled by extrinsic oxygen ion diffusion in the 5.5 to 20μ grain sizes, although the calculated ionic self-diffusion rates were higher than those predicted by the Nabarro-Herring theory. It is suggested that the discrepancy may be due to a vacancy formation mechanism, which is consistent with the observed formation of dislocation substructure and preferentially distributed porosity during creep, as well as with the observed decrease in creep rate with increasing creep strain.

SUMMARY: Details are given for the construction of a simple reciprocal shaking machine for use in small constant temperature rooms. It is particularly useful for the uniform growth of pellicle forming organisms.