bluuebunny/crossref_metadata_2025 huggingface dataset:
Ontogeny of the fused tentacles in three species of ommastrephid squids (Cephalopoda, Ommastrephidae)
Authors: Shea Elizabeth K.
Published: August 2010

Abstract. The tentacles of ommastrephid squids fuse during embryonic development and remain fused as they grow through hatching, but eventually separate to become two fully functional adult tentacles. The external anatomy of individuals at several post‐hatching ontogenetic stages of three species of ommastrephid squids (Ommastrephes bartramii, Sthenoteuthis oualaniensis, and Hyaloteuthis pelagica) was examined using scanning electron microscopy and morphometrics. The fusion of the transverse muscle mass of the tentacles was examined using light microscopy. Five ontogenetic stages of tentacle separation were defined based on landmark features such as the extent of the fusion and the presence of suckers or sucker buds at the distal tip. The total tentacle length and fused tentacle length reached a maximum when the dorsal mantle length (ML) equaled 3–4 mm (H. pelagica) or 4–6 mm (O. bartramii, S. oualaniensis), and then decreased with increasing ML. The average split length (measured from the base of the tentacles to the point of tentacle fusion) increased gradually with increasing ML, and the separate tentacle diameter was roughly half the diameter of the fused portion at all sizes. In all three species, separation of the fused tentacles began earlier in development (2–3‐mm ML) and was more advanced at smaller sizes than previously reported. The sizes presented here are conservative because excess epithelium at the location of the split may disguise the actual site of separation. Post‐separation tentacles were much shorter than the arms, and the carpal region appeared torn in 2 of the 4 specimens of S. oualaniensis examined. Finally, none of the original distal tip suckers were retained on the post‐separation tentacles of S. oualaniensis. These observations are consistent with the hypothesis that the tentacles separate gradually then rupture at the “wrist” (presumptive carpus), and argue against the possibility of prey capture by the fused tentacles.
A new encrusting interstitial marine fauna from Brazil
Authors: Winston Judith E. , Migotto Alvaro E.
Published: August 2010

Abstract. This paper reports the second occurrence of a sand‐grain encrusting interstitial epifauna dominated by bryozoans and polychaetes at a site thousands of kilometers from the first described occurrence of such a fauna 20 years ago. Such faunas seem to have gone almost unrecorded in the marine ecological literature, but they are potentially geographically widespread and ecologically significant, deserving recognition and further study by benthic ecologists. Although rooted‐erect and free‐living lunulitiform bryozoans can be abundant in soft‐bottom habitats, the presence of encrusting forms was, until recently, considered to be limited to patches of hard substrata. In 1985 and 1988, a new and seemingly unique habitat for encrusting bryozoans and other organisms on single grains of shell or sand was reported from the coastal waters of Florida, USA. Here we report a second discovery of an interstitial encrusting fauna from the continental shelf off the state of São Paulo, Brazil. In addition to the cupuladriid Discoporella umbellata, several species of bryozoans (9 cheilostomes, 3 ctenostomes, and 1 cyclostome) were found encrusting on or boring into sand grains from the 4 stations examined. Four species were found exclusively on sand to gravel size grains. The most abundant colonies, with ∼1300–1500 colonies m−2, belonged to a new species of Cleidochasma. New species of Trypostega and Reginella, each with up to 200–300 colonies m−2, were also discovered. The grain‐encrusting bryozoans were characterized by their small size, and by the fact that sexual reproduction was initiated very early in colony growth; brood chambers (for the development of embryos into larvae) occurred in colonies having only a few zooids. Colonies of boring ctenostome and cheilostome bryozoans were even more abundant than those of grain encrusting forms, being present in almost every piece of shell (∼5000–5500 colonies m−2). The fauna also included representatives of other groups of encrusting organisms, especially tubeworms (11,000–13,000 tubes m−2). Planned work on samples from additional stations on the São Paulo shelf will no doubt yield a larger number of species from various taxa and perhaps show some overlap in sand fauna species between the Brazilian and Floridian sites. In addition to the unique species of single grain encrusters, colonies of bryozoan species characteristic of larger subtidal hard substrata were also found on sand or gravel size grains, indicating that an interstitial refuge may be available to some epifaunal taxa and suggesting that this interstitial refuge, which remains almost completely unknown to benthic ecologists, may play a large role in determining distributions of those taxa.
Genetics of the relationship between the ciliate Paramecium bursaria and its symbiotic algae
Authors: Tonooka Yuki , Watanabe Tsuyoshi
Published: August 2010

Abstract. Paramecium bursaria, a freshwater protozoan, typically harbors hundreds of symbiotic algae (Chlorella sp.) in its cytoplasm. The relationship between host paramecia and symbiotic algae is stable and mutually beneficial in natural environments. We recently collected an aposymbiotic strain of P. bursaria. Infection experiments revealed that the natural aposymbiotic strain (Ysa2) showed unstable symbiosis with Chlorella sp. The algae aggregated at the posterior region of the host, resulting in aposymbiotic cell production after cell division. Cross‐breeding analyses were performed to determine the heritability of the aposymbiotic condition. In crosses of Ysa2 with symbiotic strains of P. bursaria, F1 progeny were able to form stable symbioses with Chlorella sp. However, unstable symbiosis, resembling Ysa2 infection, occurred in some F2 progeny of sibling crosses between symbiotic F1 clones. Infection experiments using aposymbiotic F2 cells showed that these F2 subclones have limited ability to reestablish the symbiosis. These results indicate that the maintenance of stable symbiosis is genetically controlled and heritable, and that Ysa2 is a mutant lacking the mechanisms to establish stable symbiosis with Chlorella sp.
Development in Berthella californica (Gastropoda: Opisthobranchia) with comparative observations on phylogenetically relevant larval characters among nudipleuran opisthobranchs
Authors: LaForge Nicole L. , Page Louise R.
Published: August 2010

Abstract. Morphological criteria defining the Nudipleura and sister group relationships among the three nudipleuran subgroups (pleurobranchoideans, anthobranch nudibranchs, and cladobranch nudibranchs) have been controversial. Analysis of larval stages may help resolve these uncertainties by identifying additional phylogenetically informative characters, but existing information on pleurobranchoidean larvae is meager. We studied larval development and metamorphosis of the pleurobranchoidean Berthella californica using histological sections, scanning and transmission electron microscopy, and immunolabeling of neurons within the larval apical ganglion. We also provide comparative data on other nudipleuran larvae that may be useful for phylogenetic reconstruction. Berthella californica fills a previously unoccupied place within an evolutionary scenario that derives nudibranchs from pleurobranchoideans, two groups in which the larval mantle fold forms the post‐metamorphic notum (dorsal epidermis). In B. californica, reflection of the mantle fold epithelium to form the notum begins at metamorphosis, as also occurs in nudibranchs, whereas mantle reflection in other pleurobranchoideans begins well before metamorphosis. Dissolution of overgrown shell walls inside the protoconch and formation of the post‐metamorphic notum from the inner epithelium of the larval mantle fold may be synapomorphies of the Nudipleura. The larval shell in B. californica is additionally noteworthy because it acquires bilateral symmetry later in development, which is very unusual among larval opisthobranchs. We demonstrate an osphradium in the larvae of two pleurobranchoideans and one anthobranch nudibranch, although adults lack this trait. We also identified an autapomorphy of cladobranch nudibranchs in the form of five ampullary neurons within the larval apical ganglion, whereas other planktotrophic opisthobranch larvae have only four of these neurons. Although our data provide morphological criteria defining both the Nudipleura and the cladobranch nudibranchs, they are insufficient to resolve sister group relationships within the Nudipleura.
Genetic and anatomic relationships among three morphotypes of the echinoid Echinocrepis rostrata
Authors: Vardaro Michael F.
Published: August 2010

Abstract. Three morphotypes—purple, tan, and white—of an irregular echinoid of the genus Echinocrepis are commonly observed in the deep North Pacific Ocean. Mitochondrial (mt) 16S DNA and cytochrome c oxidase subunit I (COI) DNA sequences were amplified from gonadal tissue samples from specimens of each morphotype. These portions of the mitochondrial genome are commonly used in species barcoding, and their similarities were compared and placed in 95% connection limit parsimony networks. All three morphotypes have similar 16S mtDNA and COI mtDNA sequences, and are thus likely representatives of the same species, Echinocrepis rostrata. Specimens of the white morphotype were smaller than the specimens of the other two morphotypes, had less gonad tissue, and had a different body shape, suggesting that it represents the juvenile form of E. rostrata. Resolving the three morphotypes into one species simplifies the identification of E. rostrata from photographs and leads to a greater understanding of the life history and reproductive cycle of a species vital to deep‐sea bioturbation and carbon sequestration.
Balancing Bio‐Energy Cropping Benefits and Water Quality Impacts: A Dynamic Optimization Approach
Authors: Eiswerth Mark E. , Van Kooten G. Cornelis
Published: August 2010

The relationship between bio‐energy feedstock production and water quality has received little attention from economists. Here, an optimal control model is used to determine the optimal amount of land to convert to the production of energy feedstocks, specifically ethanol corn, taking into account potential impacts on water quality. Based on comparative static analyses of an optimal control model, and a numerical application, we find that the optimal proportion of land to shift into bio‐energy production from a baseline use, such as the Conservation Reserve Program, depends on key model parameters, specifically the rate of degradation of the pollutant and the link between the intensity of bio‐energy feedstock production and the rate of change in the pollutant stock. Yet, there is a limit to how much land should optimally be converted as society must trade‐off its desire to mitigate climate change against its willingness to accept a decline in water quality.

Le lien entre la production de matières premières bioénergétiques et la qualité de l’eau a attiré peu d’attention de la part des économistes. Nous avons utilisé un modèle de contrôle optimal pour déterminer les superficies optimales à convertir à la production de matières premières énergétiques, en particulier le maïs destinéà la production d’éthanol, en tenant compte des répercussions potentielles sur la qualité de l’eau. D’après une simulation numérique et des analyses de statique comparative obtenues à l’aide d’un modèle de contrôle optimal, nous en sommes venus à la conclusion que les superficies optimales à convertir à la production de matières premières bioénergétiques à partir d’un instrument de référence, tel que le Conservation Reserve Program (Programme de réserve des terres sous conservation), dépend des paramètres clés du modèle, particulièrement du taux de biodégradation des polluants et du lien entre l’intensité de la production de matières premières bioénergétiques et le taux de variation du stock de polluants. Il existe tout de même une limite quant aux superficies à convertir étant donné que la société doit faire un choix entre son désir d’atténuer le changement climatique et son acceptation d’une diminution de la qualité de l’eau.
Integral-field spectroscopy of type II QSOs at z = 0.3-0.4
Authors: Humphrey A. , Villar-Martín M. , Sánchez S. F. , Martínez-Sansigre A. , Delgado R. González , Pérez E. , Tadhunter C. , Pérez-Torres M. A.
Published: August 2010

We present and analyse integral-field observations of six type II QSOs with z = 0.3–0.4, selected from the Sloan Digital Sky Survey (SDSS). Two of our sample are found to be surrounded by a nebula of warm ionized gas, with the largest nebula extending across 8 arcsec (40 kpc). Some regions of the extended nebulae show kinematics that are consistent with gravitational motion, while other regions show relatively perturbed kinematics: velocity shifts and linewidths too large to be readily explained by gravitational motion. We propose that a ∼20 × 20 kpc outflow is present in one of the galaxies. Possible mechanisms for triggering the outflow are discussed. In this object, we also find evidence for ionization both by shocks and by the radiation field of the AGN.
Origin of optically passive spiral galaxies with dusty star-forming regions. Outside-in truncation of star formation?
Authors: Bekki Kenji , Couch Warrick J.
Published: August 2010

Recent observations have revealed that red, optically passive spiral galaxies with little or no optical emission lines, harbour significant amounts of dust-obscured star formation. We propose that these observational results can be explained if the spatial distributions of the cold gas and star-forming regions in these spiral galaxies are significantly more compact than those in blue star-forming spirals. Our numerical simulations show that if the sizes of star-forming regions in spiral galaxies with disc sizes of Rd are ∼0.3Rd, such galaxies appear to have lower star formation rates as well as higher degrees of dust extinction. This is mainly because star formation in these spirals occurs only in the inner regions where both the gas densities and metallicities are higher, and hence the dust extinction is also significantly higher. We discuss whether star formation occurring preferentially in the inner regions of spirals is closely associated with the stripping of halo and disc gas via some sort of environmental effect. We suggest that the ‘outside-in truncation of star formation’ is the key to a better understanding of apparently optically passive spirals with dusty star-forming regions.
The number density of superdense early-type galaxies at 1 < z < 2 and the local cluster galaxies
Authors: Saracco P. , Longhetti M. , Gargiulo A.
Published: August 2010

Many of the early-type galaxies (ETGs) observed so far at z > 1 turned out to have smaller radii with respect to that of a typical present day ETG with comparable mass. This has generated the conviction that in the past ETGs were more compact, hence denser, and that as a consequence, they should have increased their radius across the time to reconcile with the present day ones. However, observations have not yet established whether the population of early types in the early universe was fully represented by compact galaxies nor if they were so much more numerous than in the present day Universe to require an evolution of their sizes. Here we report the results of a study based on a complete sample of 34 ETGs at 0.9 < zspec < 1.92. We find a majority (62 per cent) of normal ETGs, similar to typical local ones, co-existing with compact early types from ∼ two to ∼ six times smaller in spite of the same mass and redshift. The co-existence of normal and compact ETGs at 〈z〈 ≃ 1.5 suggests that their build-up taken place in the first 3–4 Gyr, followed distinct paths. Furthermore, we find that the number density of compact early types at 〈z〈 ≃ 1.5 is consistent with the lower limits of the local number density of compact early types derived from local clusters of galaxies. The similar number of compact early types found in the early and in the present day Universe frustrates the hypothesized effective radius evolution while provides evidence that also compact ETGs were as we see them today 9–10 Gyr ago. Finally, the fact that (at least) most of the compact ETGs at high z are accounted for by compact early types in local cluster of galaxies implies that the former are the direct progenitors of the compact early-type cluster galaxies establishing a direct link between environment and early phases of assembly of ETGs.
State‐of‐the‐Practice Review of In Situ Thermal Technologies
Authors: Triplett Kingston Jennifer L. , Dahlen Paul R. , Johnson Paul C.
Published: August 2010

In situ thermal‐based soil and aquifer remediation technologies (e.g., electrical resistance heating [ERH], conductive heating, and steam‐based heating) have undergone rapid development and application in recent years. These thermal technologies offer the promise of more rapid and thorough treatment of nonaqueous phase liquid (NAPL) source zones; however, their field‐scale application has not been well documented in the technical literature. A state‐of‐the‐practice review of the application of these technologies was conducted in this study. Available documents from 182 applications were reviewed, which included 87 ERH, 46 steam‐based heating, 26 conductive heating, and 23 other heating technology applications conducted between 1988 and 2007. Approximately 90% of the 182 applications were implemented after 1995 and about half since 2000. More specifically, this review identified the geologic settings in which these technologies were applied, chemicals treated, design parameters, operating conditions, and performance metrics. The results of this study are summarized in a table linking this information to five generalized geologic scenarios. Practitioners considering thermal technologies for their site can identify the geologic scenario that most closely resembles their site and then can quickly see which technologies have been applied in that setting, the designs employed, operating conditions, and the performance achieved.
DESTINATION EFFECTS: RESIDENTIAL MOBILITY AND TRAJECTORIES OF ADOLESCENT VIOLENCE IN A STRATIFIED METROPOLIS*
Authors: SHARKEY PATRICK , SAMPSON ROBERT J.
Published: August 2010

Two landmark policy interventions to improve the lives of youth through neighborhood mobility—the Gautreaux program in Chicago and the Moving to Opportunity (MTO) experiments in five cities—have produced conflicting results and have created a puzzle with broad implications: Do residential moves between neighborhoods increase or decrease violence, or both? To address this question, we analyze data from a subsample of adolescents ages 9–12 years from the Project on Human Development in Chicago Neighborhoods, a longitudinal study of children and their families that began in Chicago—the site of the original Gautreaux program and one of the MTO experiments. We propose a dynamic modeling strategy to separate the effects of residential moving across three waves of the study from dimensions of neighborhood change and metropolitan location. The results reveal countervailing effects of mobility on trajectories of violence; whereas neighborhood moves within Chicago lead to an increased risk of violence, moves outside the city reduce violent offending and exposure to violence. The gap in violence between movers within and outside Chicago is explained not only by the racial and economic composition of the destination neighborhoods but also by the quality of school contexts, adolescents' perceived control over their new environment, and fear. These findings highlight the need to simultaneously consider residential mobility, mechanisms of neighborhood change, and the wider geography of structural opportunity.
THE ROLE OF CRIME IN HOUSING UNIT RACIAL/ETHNIC TRANSITION*
Authors: HIPP JOHN R.
Published: August 2010

Previous research frequently has observed a positive cross‐sectional relationship between racial/ethnic minorities and crime and generally has posited that this relationship is entirely because of the effect of minorities on neighborhood crime rates. This study posits that at least some of this relationship might be a result of the opposite effect—neighborhood crime increases the number of racial/ethnic minorities. This study employs a unique sample (the American Housing Survey neighborhood sample) focusing on housing units nested in microneighborhoods across three waves from 1985 to 1993. This format allows one to test and find that such racial/ethnic transformation occurs because of the following effects: First, White households that perceive more crime in the neighborhood or that live in microneighborhoods with more commonly perceived crime are more likely to move out of such neighborhoods. Second, Whites are significantly less likely to move into a housing unit in a microneighborhood with more commonly perceived crime. And third, African American and Latino households are more likely to move into such units.
ALL OFFENDERS ARE EQUAL, BUT SOME ARE MORE EQUAL THAN OTHERS: VARIATION IN JOURNEYS TO CRIME BETWEEN OFFENDERS*
Authors: TOWNSLEY MICHAEL , SIDEBOTTOM AIDEN
Published: August 2010

The results of this study reveal a major methodological problem with an established body of criminological literature—the journey to crime. The dominant finding of such research is that most crimes occur close to an offender's home. Consequently, journeys to crime typically display a distance‐decay function that is assumed to exist between and within offenders. However, most journey‐to‐crime studies use nested data—individual offenders contributing multiple crime trips—yet employ analytic methods that fail to account for this property, leading to inference and aggregation concerns. In the study outlined in this article, we demonstrated the implications of using nested data for analyzing the journey to crime. We showed that once controlling for nesting, only a few (prolific) offenders display a distance decay pattern. Implications of the findings for theory and future research are discussed.
Apelin stimulation of duodenal bicarbonate secretion: feeding‐dependent and mediated via apelin‐induced release of enteric cholecystokinin
Authors: Flemström G. , Mäkelä K. , Purhonen A. K. , Sjöblom M. , Jedstedt G. , Walkowiak J. , Herzig K. H.
Published: August 2010

Aims:  Apelin peptides are the endogenous ligand of the G protein‐coupled receptor APJ. Proposed actions include involvement in control of cardiovascular functions, appetite and body metabolism. We have investigated the effects of apelin peptides on duodenal bicarbonate secretion in vivo and the release of cholecystokinin (CCK) from acutely isolated mucosal cells and the neuroendocrine cell line STC‐1.

Methods:  Lewis × Dark Agouti rats had free access to water and, unless fasted overnight, free access to food. A segment of proximal duodenum was cannulated in situ in anaesthetized animals. Mucosal bicarbonate secretion was titrated (pH stat) and apelin was administered to the duodenum by close intra‐arterial infusion. Total RNA was extracted from mucosal specimens, reverse transcripted to cDNA and the expression of the APJ receptor measured by quantitative real‐time PCR. Apelin‐induced release of CCK was measured using (1) cells prepared from proximal small intestine and (2) STC‐1 cells.

Results:  Even the lowest dose of apelin‐13 (6 pmol kg−1 h−1) caused a significant rise in bicarbonate secretion. Stimulation occurred only in continuously fed animals and even a 100‐fold greater dose (600 pmol kg−1 h−1) of apelin was without effect in overnight food‐deprived animals. Fasting also induced an eightfold decrease in the expression of APJ receptor mRNA. Apelin induced significant release of CCK from both mucosal and STC‐1 cells, and the CCKA receptor antagonist devazepide abolished bicarbonate secretory responses to apelin.

Conclusion:  Apelin‐induced stimulation of duodenal electrolyte secretion is feeding‐dependent and mediated by local mucosal release of CCK.
THE CHARACTERISATION AND PATHOGENICITY OF PORCINE ENTEROVIRUSES ISOLATED IN VICTORIA
Authors: Forman A. J. , Pass D. A. , Connaughton I. D.
Published: August 2010

SUMMARY Approximately 23 viruses were isolated from healthy pigs, pigs with encephalitis, and in cases of reproductive failure. Five viruses were identified as enteroviruses and a total of 10 isolates were shown to cross‐react serologically to varying degrees. Twenty viruses were neutralised by a reference antiserum of serotype 8 porcine enterovirus.

Intracerebral inoculation of colostrum‐deprived piglets with 2 of the characterised viruses caused lesions of encephalomyelitis which were not induced by oral infection. Intrafoetal inoculation of 2 sows with one characterised faecal isolate caused foetal death and abortion, but no adverse effects followed oral dosage.
A SURVEY OF CLINICAL MASTITIS IN SOUTH‐EAST QUEENSLAND DAIRY HERDS
Authors: Daniel R. C. W. , O'boyle D. , Marek M. S. , Frost A. J.
Published: August 2010

SUMMARY A survey of clinical mastitis in 26 South‐East Queensland dairy herds supplying more than 300,000 litres of milk annually, revealed a quarter incidence of 2.6% with a cow incidence of 9% over a 3‐month period. Secretion samples from cows yielded Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, coliforms, Pseudomonas spp and other bacteria in 38.5%, 12.5%, 6.6%, 3.4%, 2.6%. 0.6% and 2.0% of cases respectively. Samples from 38% of the cases were culturally negative while at least 38% of the clinical quarters had shown a previous clinical episode of mastitis. There was a significant association (P < 0.025) between herd and the likelihood of a negative culture result on samples from clinical cases. Twenty‐one percent of cases occurred in the first month of lactation and 10.3% in the first week. There was a significant association (P < 0.005) between the age of cow and the stage of lactation in which clinical cases occurred in that cows in the 2 to 5 year age group were more likely to suffer attacks in the earlier part of lactation. There was a highly significant relationship (P < 0.005) between cow age group and the proportion of affected quarters and it was calculated that the change with each year of age was a 55% increase over the previous year. Forty‐five percent of the isolates of S. aureus were resistant to penicillin.
Current status of foot‐and‐mouth disease vaccines including the use of genetic engineering
Authors: DELLA‐PORTA A. J.
Published: August 2010

SUMMARY Foot‐and‐mouth disease virus (FMDV) vaccines are used to protect animals against infection by the 7 FMDV serotypes composed of greater than 60 FMDV subtypes. Because of problems of both live attenuated and inactivated FMDV vaccines and also because of the very large market for an effective safe vaccine, research into other types of vaccines has been undertaken. One of the 4 virus structural proteins, VP1, is believed to be the main protein that stimulates virus neutralising antibodies and studies have concentrated on its potential as a subunit vaccine. Genetic engineering has been used to clone the VF1 gene of FMDV and VP1 synthesised from the cloned gene has been used in experimental vaccine studies. The studies in small numbers of cattle and pigs demonstrated that 2 vaccinations with genetically engineered VP1 could confer protection against FMDV challenge. However, there are a number of areas that need further research before such a genetically engineered vaccine could be used commercially. The use of chemically synthesised antigenic fragments of VP1 has recently been reported, and these synthetic fragments appear to be potentially better at producing immunity to FMDV than the whole genetically engineered VP1 protein, perhaps because of conformational problems in the presentation of whole VP1. Other possible future directions in the research and in the development of safe, effective FMDV vaccines are discussed. In conclusion, although very significant progress has been made in cloning FMDV‐VP1 genes, we are still far from a genetically engineered VP1‐FMDV subunit vaccine. In the meantime, properly inactivated and safety‐tested FMDV vaccines will continue to be used and to be of benefit to the livestock industry in countries where foot‐and‐mouth is endemic or in combating introductions of the disease.
The pattern of endemic parvovirus infection in four pig herds
Authors: POINTON A. M. , SURMAN P. G. , McCLOUD P. I. , WHYTE P. B. D.
Published: August 2010

SUMMARY Serological surveys were conducted on the gilts and adult sows in 4 herds endemically infected with porcine parvovirus. The study assessed the influence of the type of management of breeders on the spread of virus infection and the influence of endemic parvovirus infection on reproductive parameters of the herd.

The practice of holding gilts and sows in groups did not reliably promote infection or maintain a 100% level of active immunity amongst adult sows in 2 of 3 group husbandry herds. In the 4 herds, the prevalence of adult sows (>12 months) with active immune haemagglutination inhibition titres (> 256) ranged between 44% and 100%, while between 0% and 100% of gilts (6 to 12 months of age) had active immune titres. Fully susceptible gilts older than 9 months of age held in groups, failed to become infected by 12 months of age on farms endemically infected with PPV. In 2 herds a continued low infection rate of gilts resulted in increasing the potential of breeding animals becoming susceptible to parvovirus infection as infected sows were replaced by noninfected gilts. In both herds, epidemics of parvovirus infection followed, which were characterised by an increase in reproductive failure. Parvovirus infection during the first 70 days of pregnancy reduced the average number of piglets born alive per litter by 1.6 piglets (p < 0.05). This was due to the combined effect of more piglets being born dead per litter and an overall reduction in litter size.
Clinical pathology of experimental stephanuriasis in pigs
Authors: HUTCHINSON G.W. , WANDURAGALA L. , TAMPUBOLON M.
Published: August 2010

SUMMARY Haematology and serum aspartate aminotransferase and alanine aminotransferase activities were studied during the migration phase of Stephanurus dentatus in the livers of experimentally infected pigs. There was no evidence of anaemia but total leucocyte counts were raised and peripheral eosinophilia began 2 to 3 weeks after infection. Peak eosinophilia occurred 6 to 7 weeks after infection and levels were still elevated at 20 weeks. Lymphocyte and neutrophil numbers remained constant. Reinfection did not stimulate a secondary eosinophil response. Only aspartate aminotransferase was temporarily elevated.

The gross pathology resulting from the infections is described. Several clinicopathological differences in the response of pigs to invasion of the liver by S. dentatus were noted compared to those produced by Ascaris suum but none are pathognomonic.
Outbreaks of photosensitisation and deaths in cattle due to Myoporum aff.Insulare R. Br. toxicity
Authors: JERRETT I. V. , CH1NNOCK R. J.
Published: August 2010

SUMMARY Outbreaks of photosensitisation and deaths in cattle on 5 farms in Victoria occurred following access to Myoporum affinity insulare. Signs were observed 2 to 6 days after access to Myoporum trees or pruned branches and included depression, anorexia, photosensitisation, constipation, agalactia, jaundice, and mucosal petechiation. Serum gamma glutamyl transferase and aspartate amino transferase ievels were elevated in all cases. Gross findings in fatally intoxicated cows consisted of widespread haemorrhages and pale yellow mottling of the liver. Distinctive histological lesions of periportal hepatic necrosis and bile duct proliferation were seen in all cases.

An 8‐month‐old heifer given 30 g/kg fresh minced leaves by stomach tube died approximately 70 h after initial dosing. Post‐mortem findings of widespread haemorrhage and hepatic periportal necrosis and bile duct proliferation were identical to those of field cases.
News from the Scientific Organising Committee Learning new tricks to treat old dogs
Authors: Revington Dr Maureen , Walker Natalie
Published: August 2010

Treating elderly pets and maximising your practice returns will be in focus at this year's AVA Annual Conference. The Scientific Organising Committee is delighted that such distinguished international and local speakers have agreed to give presentations in the Small Animal (Geriatric Medicine and Surgery) and Practice Management streams at the conference.

The AVA Conference will be at Hobart's Wrest Point Conference Centre from May 21–26, 2006. To see the full program and to register online visit www.ava.com.au/avaconference.
Article
Authors: JORGENSEN WK , ANDERSON GR , JESTON PJ , BLIGHT GW , MOLLOY JB
Published: August 2010

ObjectiveTo attenuate two strains ofEimeria tenellaby selecting for precocious development and evaluate the strains in characterisation trials and by field evaluation, to choose one precocious line for incorporation into an Australian live coccidiosis vaccine for poultry.

DesignTwo strains from non‐commercial flocks were passaged through chickens while selecting for precocious development. Each strain was characterised for drug sensitivity, pathogenicity, protection against homologous and heterologous challenge, and oocyst output in replicated experiments in which the experimental unit was a cage of three birds. Oocyst output and/or body weight gain data collected over a 10 to 12 day period following final inoculation were measured. Feed conversion ratios were also calculated where possible.

ResultsFifteen passages resulted in prepatent periods reduced by 24 h for the Redlands strain (from 144 h to 120 h) and 23 h for the Darryl strain (from 139 h to 116 h). Characterisation trials demonstrated that each precocious line was significantly less pathogenic than its parent strain and each effectively induced immunity that protected chickens against challenge with both the parent strain and other virulent field strains. Both lines had oocyst outputs that, although significantly reduced relative to the parent strains, remained sufficiently high for commercial vaccine production, and both showed susceptibility to coccidiostats.

ConclusionTwo attenuated lines have been produced that exhibit the appropriate characteristics for use in an Australian live coccidiosis vaccine.
OECD Efforts to Address the Measurement and Policy Challenges Posed by the Information Society
Authors: Wyckoff Andrew W.
Published: August 2010

The OECD has acted as a forum for the discussion of policies regarding the information society for over 20‐years, producing guidelines and recommendations in areas such as privacy of personal information, computer security, cryptography, regulatory reform of communications, and most recently on‐line consumer protection and the taxation of e‐commerce. By and large, this work was undertaken without the benefit of statistical measures. But the economic performance of a number of OECD Member countries during the 1990s underscores that the policy challenges being posed by the information society are increasingly economic in nature—how ICT is affecting productivity, growth rates, inflation, labour markets etc.—necessitating the need for statistically rigorous data. This paper outlines how recent efforts by national statistical offices to improve this situation have allowed researchers to gain new insight into the economic impact associated with ICTs and applications like e‐commerce, leading to a number of policy recommendations as to how best to exploit the economic potential of these technologies. The paper ends by outlining important policy issues that require new statistical efforts.
The Citizens' Right to Information and the Duties of a Democratic State in Modern IT Environment in the Light of the UN Fundamental Principles of Official Statistics and the ISI Declaration on Statistical Ethics
Authors: Oleński Józef
Published: August 2010

Modern information technologies, particularly the technology of very large data bases, Internet and modern mass media, have changed the processes of production, storage and dissemination of information. These technologies have a direct impact on the practical realization of citizens' rights to information. In democratic societies, in modern IT environment, information is produced and disseminated by many social and economic entities. Many producers and disseminators of information do not know or do not obey the criteria which should be met by any information delivered to the public. In this paper the advantages and the threats for the citizens' rights to information generated by the distribution and globalization of information processes in modern IT environment are discussed.

It seems that for the protection of the citizens' rights to information, there is the need for specification and codification of quality criteria and standards for information produced and disseminated with the use of modern IT. Official statistics may and should play an important and active role in defining those criteria and standards. Professional ethics of statisticians and of official statistics seems to be the proper basis for that. Ethical principles of statistics are formulated in two basic documents: The fundamental principles of official statistics adopted by the UN Statistical Commission in 1994 and the ISI Declaration on statistical ethics adopted by the ISI in 1985.
Measuring Knowledge Development and Developing Official Statistics for the Information Age
Authors: Ramachandran R.
Published: August 2010

Measuring knowledge development is a new statistical activity that warrants urgent attention in the light of the current Internet explosion. The Internet creates virtual networks by connecting information nodes, knowledge nexus, people and institutions. The Internet has resulted in an unprecedented proliferation of Information, Communication, Knowledge and Entertainment (ICKE), which has in turn brought about structural changes in all aspects of social, economic and political governance. For public policy formulators, including the statistical community, it is imperative that the knowledge development aspect of ICKE be measured. Being abstract, knowledge is difficult to quantify. However, the manifestations of attributes and variables of any knowledge development activity are measurable. The paper outlines a conceptual framework for achieving this. This proposed framework adopts a socio‐technological approach, premised on contemporary information and knowledge development as an integral of the people and technology dimensions. To illustrate the workability of the proposed model, the paper identifies some parameters and variables in the current statistical system, and highlights some new data generated via the Internet Subscriber Study and ICT Exposition Visitor Study. All illustrations refer to Malaysian data. Finally, the paper outlines ‘way forward’ initiatives for establishing a full‐fledged set of information and knowledge development indicators.
Statistical Regularity and Free Will: L.A.J. Quetelet and P.A. Nekrasov
Authors: Seneta Eugene
Published: August 2010

In the 19th century, causes of empirically observed stability of averages in settings relating to human behaviour were a topic of intense discussion in western Europe. This followed an extensive study of empirical stability by the founder of modern statistics (and of the International Statistical Institute) L.A.J. Quetelet, published in 1835, in what he called “Social Physics”. The eminent mathematician of strong probabilistic and philosophical inclination and Russian Orthodox religious belief, P.A. Nekrasov, took up and modified Quetelet's Social Physics in 1902, with (social) independence seen as prime cause of statistical regularity. Our paper focuses on the role free will plays in the statistical writings of Quetelet and of Nekrasov. The work of the latter has remained little known in general, mainly for politico‐ideological reasons.
Bridging the Gap between Different Statistical Approaches: An Integrated Framework for Modelling
Authors: Kuhnert Petra M. , Mengersen Kerrie , Tesar Peter
Published: August 2010

This paper proposes a template for modelling complex datasets that integrates traditional statistical modelling approaches with more recent advances in statistics and modelling through an exploratory framework. Our approach builds on the well‐known and long standing traditional idea of ‘good practice in statistics’ by establishing a comprehensive framework for modelling that focuses on exploration, prediction, interpretation and reliability assessment, a relatively new idea that allows individual assessment of predictions.

The integrated framework we present comprises two stages. The first involves the use of exploratory methods to help visually understand the data and identify a parsimonious set of explanatory variables. The second encompasses a two step modelling process, where the use of non‐parametric methods such as decision trees and generalized additive models are promoted to identify important variables and their modelling relationship with the response before a final predictive model is considered. We focus on fitting the predictive model using parametric, non‐parametric and Bayesian approaches.

This paper is motivated by a medical problem where interest focuses on developing a risk stratification system for morbidity of 1,710 cardiac patients given a suite of demographic, clinical and preoperative variables. Although the methods we use are applied specifically to this case study, these methods can be applied across any field, irrespective of the type of response.
A Bayesian Formulation of Exploratory Data Analysis and Goodness‐of‐fit Testing*
Authors: Gelman Andrew
Published: August 2010

Exploratory data analysis (EDA) and Bayesian inference (or, more generally, complex statistical modeling)—which are generally considered as unrelated statistical paradigms—can be particularly effective in combination. In this paper, we present a Bayesian framework for EDA based on posterior predictive checks. We explain how posterior predictive simulations can be used to create reference distributions for EDA graphs, and how this approach resolves some theoretical problems in Bayesian data analysis. We show how the generalization of Bayesian inference to include replicated datayrepand replicated parametersθrepfollows a long tradition of generalizations in Bayesian theory.

On the theoretical level, we present a predictive Bayesian formulation of goodness‐of‐fit testing, distinguishing betweenp‐values (posterior probabilities that specified antisymmetric discrepancy measures will exceed 0) andu‐values (data summaries with uniform sampling distributions). We explain thatp‐values, unlikeu‐values, are Bayesian probability statements in that they condition on observed data.

Having reviewed the general theoretical framework, we discuss the implications for statistical graphics and exploratory data analysis, with the goal being to unify exploratory data analysis with more formal statistical methods based on probability models. We interpret various graphical displays as posterior predictive checks and discuss how Bayesian inference can be used to determine reference distributions.

The goal of this work is not to downgrade descriptive statistics, or to suggest they be replaced by Bayesian modeling, but rather to suggest how exploratory data analysis fits into the probability‐modeling paradigm.

We conclude with a discussion of the implications for practical Bayesian inference. In particular, we anticipate that Bayesian software can be generalized to draw simulations of replicated data and parameters from their posterior predictive distribution, and these can in turn be used to calibrate EDA graphs.
Statistical Surveillance. Optimality and Methods
Authors: Frisén Marianne
Published: August 2010

Different criteria of optimality are used in different subcultures of statistical surveillance. One aim with this review is to bridge the gap between the different areas. The shortcomings of some criteria of optimality are demonstrated by their implications. Some commonly used methods are examined in detail, with respect to optimality. The examination is made for a standard situation in order to focus on the inferential principles. A uniform presentation of methods, by expressions of likelihood ratios, facilitates the comparisons between methods. The correspondences between criteria of optimality and methods are examined. The situations and parameter values for which some commonly used methods have optimality properties are thus determined. A linear approximation of the full likelihood ratio method, which satisfies several criteria of optimality, is presented. This linear approximation is used to examine when linear methods are approximately optimal. Methods for complicated situations are reviewed with respect to optimality and robustness.
Sentencing Illicit Drug Traffickers: How do the Courts Handle Random Sampling Issues?
Authors: Izenman Alan J.
Published: August 2010

While many European justice systems distinguish between possession of and trafficking in illicit drugs, sentencing in drug cases in those countries tends not to depend (at least formally) upon the quantity of drugs seized from a defendant, but rather on the circumstances in which the defendant was found with drugs. Courts in the United States, on the other hand, penalize those convicted of drug crimes through an elaborate system of sentencing rules and guidelines. These sentences depend only upon the amount of drugs (possibly adjusted for circumstances) and the defendant's criminal history. Because of the enormous amount of work needed to determine drug type and quantity in each case, sampling the evidence and estimates of drug quantity have been accepted in most courts in the United States. During the last two years, several major developments in U.S. federal sentencing have taken place. It all started in June 2000 with the Supreme Court case Apprendi v. New Jersey, in which Justice O'Connor, in dissent, termed a “watershed in constitutional law”. Prior toApprendi, a judge would sentence a convicted drug trafficker to imprisonment using the preponderance standard of proof on the quantities of drugs seized. The affect ofApprendiis to make more juries decide the quantity of drugs by the reasonable doubt standard. AlthoughApprendihad nothing to do with illicit drugs, the implication now is that all federal sentencing protocols are under revision. SinceApprendiwas decided, huge numbers of cases involving convicted drug traffickers have relied upon its reasoning on appeal, with the result that a ruling from the Supreme Court on further clarification of this issue is expected. This article discusses the impact so far ofApprendion statistical issues involved in estimating total drug quantity and considers possible future directions under the changing protocols.
Discussion: Efficiency and Self‐efficiency With Multiple Imputation Inference
Authors: Meng Xiao‐Li , Romero Martin
Published: August 2010

By closely examining the examples provided in Nielsen (2003), this paper further explores the relationship between self‐efficiency (Meng, 1994) and the validity of Rubin's multiple imputation (RMI) variance combining rule. The RMI variance combining rule is based on the common assumption/intuition that the efficiency of our estimators decreases when we have less data. However, there are estimation procedures that will do the opposite, that is, they can produce more efficient estimators with less data. Self‐efficiency is a theoretical formulation for excluding such procedures. When a user, typically unaware of the hidden self‐inefficiency of his choice, adopts a self‐inefficient complete‐data estimation procedure to conduct an RMI inference, the theoretical validity of his inference becomes a complex issue, as we demonstrate. We also propose a diagnostic tool for assessing potential self‐inefficiency and the bias in the RMI variance estimator, at the outset of RMI inference, by constructing a convenient proxy to the RMI point estimator.