Silicate Volcanism on Europa's Seafloor and Implications for Habitability.

Habitable ocean environments on Europa require an influx of reactants to maintain chemical disequilibrium. One possible source of reactants is seafloor volcanism. Modeling has shown that dissipation of tidal energy in Europa's asthenosphere can generate melt, but melt formation cannot be equated with volcanism. Melt must also be transported through Europa's cold lithosphere to erupt at the seafloor. Here, we use two models of dike propagation to show that dikes can only traverse the lithosphere if either the fracture toughness of the lithosphere or the flux into the dike is large (>500 MPa m1/2 or ∼1 m2 s-1, respectively). We conclude that cyclic volcanic episodes might provide reactants to Europa's ocean if magma accumulates at the base of the lithosphere for several thousand years. However, if dikes form too frequently, or are too numerous, the magma flux into each will be insufficient, and volcanism cannot support a habitable ocean environment.

Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution.

Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.

Trichodinosis associated with pathology of the reproductive tract in waterfowl.

Trichodinid ciliophorans are opportunistic parasites of many species of fish, amphibians, and molluscs, but yet never reported in association with lesions in birds. Postmortem and histopathological evaluation of a commercial adult Toulouse gander and female goose, and a wild Mallard drake revealed the presence of severe pathological parasitic colonization of their reproductive tracts. Histopathological findings included moderate to severe granulocytic inflammation, acanthosis, accentuation of the rete pegs, and proliferative hyperplastic squamous metaplasia of the mucosa of the ejaculatory ducts and groove, sulcus spermaticus, glandular part of the phallus (cavum penis), and oviduct in association with large numbers of ciliated protozoa anchored to the tissues or free in the lumen. These protozoa had characteristic morphological features analogous to the family of Trichodinidae. The source of this parasitism could not be determined. To our knowledge, this is the first report of trichodinosis associated with pathology in birds.

An Unusual Outbreak of Chlamydiosis in Commercial Turkeys Involving the Nasal Glands.

An unusual outbreak of chlamydiosis was diagnosed in 15,000, 13-wk-old organically grown turkeys housed in a semiconfinement housing system. The disease was characterized by unilateral or bilateral swelling above the eye due to mild-to-severe inflammation of the nasal glands in 3%-5% of the birds. Except for a slight drop in feed and water consumption, the birds did not exhibit any respiratory signs, morbidity, and mortality. Chlamydiosis in the turkeys was confirmed by immunofluorescence, immunohistochemistry, and PCR assay of the nasal glands. Other samples such as conjunctiva, lungs, air sacs, heart, liver, spleen, and feces were negative for chlamydia by florescence antibody test in birds submitted over several weeks. Chlamydia psittaci strain B was isolated in chicken egg embryos and typed by multilocus sequence variable number of tandem repeats analysis, multilocus sequence typing, and ompA gene sequencing as a CP3-like strain. This is the first report of a naturally occurring chlamydiosis affecting the nasal glands in turkeys.

Cervical cancer incidence in young women: a historical and geographic controlled UK regional population study.

BACKGROUND: The commencing age of cervical screening in England was raised from 20 to 25 years in 2004. Cervical cancer incidence in young women of England is increasing. It is not clear if this is due to either greater exposure to population risk factors or reduced cervical screening. METHODS: We measured if the relative risk of cervical cancer in younger women (20-29 years) of the north-east of England (NE) differed to that of women aged 30yrs and above since 2004. We also measured average annual percentage change (AAPC) in the 3 yr moving average incidence for all age-groups. Regional screening coverage rate and population risk factors were reviewed. Comparisons were made with Wales where screening continues to commence from the age of 20yrs. RESULTS: Cervical cancer incidence in women aged 20-29 increased annually by an average of 10.3% between 2000 and 2009. The rise in women aged 30-39 was less steep (3.5%/year) but no significant rise was observed in women aged 40-49. Socioeconomic factors remained stable or improved during the time period except for the incidence of chlamydia, herpes simplex and in particular, genital warts, which increased significantly in young women. Data from Wales show similar results. CONCLUSION: The incidence of cervical cancers in young women of the NE is increasing. The rise in incidence is unrelated to the change in screening policy in 2004. Close monitoring of incidence in young women and a greater attempt to reverse the current decline in screening coverage of women aged 25-29 years are recommended.

Atypical distribution of fowl pox lesions in broilers.

An unusual cutaneous fowl pox outbreak occurred in 8-wk-old broilers in California. Rounded and longitudinal, proliferative scratch-associated lesions were found only in feathered areas of the body. Both sides of the hip, the lower abdomen, pericloacal area, and lateral lower neck area were involved. The head, legs, feet, and toes did not have lesions. Birds in only one section of one of five houses were affected. Fifteen percent condemnations occurred in birds from the affected house due to the skin lesions. A diagnosis of fowl pox was achieved by histopathology, viral isolation, and direct electron microscopy. The unusual distribution of pox lesions was assumed to be associated with skin scratches. There was no evidence that mosquitoes or other types of insects were involved in this outbreak. To the knowledge of the authors, this is the first report of this kind of unusual fowl pox in the United States.

Supporting Indian nurses migrating to New Zealand: a literature review.

BACKGROUND: New Zealand, like many other Western countries, is struggling to cope with increasing demands for nursing services. Registered nurses are being actively recruited internationally and New Zealand has become a popular destination for nurses who wish to emigrate, including those from India. These nurses have unique cultural, professional and educational needs yet it is unclear how to best support them as they move to their destination countries. AIMS: The issues around nursing migration and its effects have been discussed in many forums, but there is evidence of a gap in understanding the issues around acculturation and socialization. This selected literature review sought to identify the significant factors that impact on migrating nurses becoming competent and confident registered nurses in the New Zealand practice environment. METHODS: A bibliographical database search was undertaken (Web of Knowledge, Web of Science, CINAHL, Medline, Academic Search Elite, and Ebscohost EJS) along with national and international nursing websites for the period 2002-2009. Search terms included Indian nurse, international nurse, migration, experience, cultural safety, globalization, nurse migration, nurse recruitment, New Zealand and research. The search was limited to texts published in English, with preference given to peer-reviewed research-based articles. RESULTS: A significant volume of literature was located. The key themes that arose were migration, education, language, nursing skills, competence, cultural safety and reflection on practice. Literature considered to best reflect these main themes, and of most relevance to New Zealand, was selected for this review, with preference given to research reports and official nursing publications. CONCLUSION: Strategies such as providing ongoing professional education, ensuring cultural safety and offering mentoring in practice environments will contribute to a safe passage for migrating nurses. Further research is required into the acculturation and socialization of Indian nurses, especially those moving to New Zealand.

Respiratory tract trichomoniasis in breeder squab candidates in Northern California.

Breeder squab candidates between the ages of 6 and 16 wk were submitted to the California Animal Health and Food Safety Laboratory, Turlock branch, as a result of respiratory distress and increased mortality. These cases were submitted from one Northern California commercial squab operation on three separate occasions occurring between December 2007 and March 2008. Severe trichomoniasis was identified, primarily in the tracheal epithelium and lung of squabs, with few or no lesions in the oral cavity, crop, esophagus, and livers, where the organism commonly infiltrates. Infiltration of the trachea and lung sections with trichomonads was associated with a severe inflammatory response in the surrounding tissue. Diagnosis was confirmed with the use of histopathology and an immunoperoxidase special stain. Oxytetracycline supportive antibiotic therapy to prevent secondary bacterial infections was administered to remaining squabs on the farm, but no specific treatment regimen was instituted. This novel respiratory presentation of trichomoniasis continued over a period of 3 mo, until mortality gradually returned to normal.

Landslides on Ceres: Diversity and Geologic Context.

Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first-order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta-like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice.

A systematic review of the routine monitoring of growth in children of primary school age to identify growth-related conditions.

OBJECTIVES: To clarify the role of growth monitoring in primary school children, including obesity, and to examine issues that might impact on the effectiveness and cost-effectiveness of such programmes. DATA SOURCES: Electronic databases were searched up to July 2005. Experts in the field were also consulted. REVIEW METHODS: Data extraction and quality assessment were performed on studies meeting the review's inclusion criteria. The performance of growth monitoring to detect disorders of stature and obesity was evaluated against National Screening Committee (NSC) criteria. RESULTS: In the 31 studies that were included in the review, there were no controlled trials of the impact of growth monitoring and no studies of the diagnostic accuracy of different methods for growth monitoring. Analysis of the studies that presented a 'diagnostic yield' of growth monitoring suggested that one-off screening might identify between 1:545 and 1:1793 new cases of potentially treatable conditions. Economic modelling suggested that growth monitoring is associated with health improvements [incremental cost per quality-adjusted life-year (QALY) of 9500 pounds] and indicated that monitoring was cost-effective 100% of the time over the given probability distributions for a willingness to pay threshold of 30,000 pounds per QALY. Studies of obesity focused on the performance of body mass index against measures of body fat. A number of issues relating to human resources required for growth monitoring were identified, but data on attitudes to growth monitoring were extremely sparse. Preliminary findings from economic modelling suggested that primary prevention may be the most cost-effective approach to obesity management, but the model incorporated a great deal of uncertainty. CONCLUSIONS: This review has indicated the potential utility and cost-effectiveness of growth monitoring in terms of increased detection of stature-related disorders. It has also pointed strongly to the need for further research. Growth monitoring does not currently meet all NSC criteria. However, it is questionable whether some of these criteria can be meaningfully applied to growth monitoring given that short stature is not a disease in itself, but is used as a marker for a range of pathologies and as an indicator of general health status. Identification of effective interventions for the treatment of obesity is likely to be considered a prerequisite to any move from monitoring to a screening programme designed to identify individual overweight and obese children. Similarly, further long-term studies of the predictors of obesity-related co-morbidities in adulthood are warranted. A cluster randomised trial comparing growth monitoring strategies with no growth monitoring in the general population would most reliably determine the clinical effectiveness of growth monitoring. Studies of diagnostic accuracy, alongside evidence of effective treatment strategies, could provide an alternative approach. In this context, careful consideration would need to be given to target conditions and intervention thresholds. Diagnostic accuracy studies would require long-term follow-up of both short and normal children to determine sensitivity and specificity of growth monitoring.

Vitamin A deficiency in turkey poults.

Vitamin A deficiency was diagnosed in a commercial flock of 13,000 4-6-week-old turkey poults in the summer of 2004. The birds were initially submitted for examination because of a 3% increase in the reported daily mortality of the flock. Clinically, affected birds had stunted growth and ruffled feathers, showed signs of incoordination, and were depressed. At necropsy, pale white pseudomembranous to mucoid material was observed on the mucosal surface of the tongue, oral cavity, portions of the esophagus, and the crop of some birds. Histologically, there was squamous metaplasia of the mucosal epithelium of the oral mucosa, esophagus, sinuses, nasal glands, bronchi, proventriculus, and the bursa of Fabricius. Vitamin A was not detected in the feed sample at a detection limit of 0.5 mg/kg. Serum vitamin A concentrations in 7 birds were very low and ranged from 0.05 to 0.1 mg/L. Vitamin A concentrations in livers were extremely low (0.1 mg/kg wet weight, 1/7 poults) or undetectable (< 0.1 mg/kg wet weight, 6/7 poults). A diagnosis of vitamin A deficiency was made based on gross and microscopic lesions and vitamin A concentrations in serum, liver, and feed. To the authors' knowledge, this is the first documented case of vitamin A deficiency in poults submitted from a commercial meat turkey producer comparatively depicting the gross and microscopic lesions with those found in other species of birds and mammals.

A Novel Mycoplasma sp. Associated with Phallus Disease in Goose Breeders: Pathological and Bacteriological Findings.

In April 2014, poor fertility in a major commercial goose breeder operation in California triggered the submission of six live affected Toulouse ganders ( Anser anser ) to the California Animal Health and Food Safety Laboratory, Turlock branch (University of California-Davis). Toulouse were principally affected among all breeds, and their egg fertility dropped from 65.7% to less than 33.9% in the first 40 days of the 2014 breeding season. The flock consisted of 410 adult birds, 90 males and 320 females, between 2 and 5 yr of age. Inspection of the flock revealed that 44.4% of the Toulouse ganders had severe phallic deformities that prevented them from mating. At postmortem examination, severe yellowish fibrocaseous exudate disrupted the architecture of the phallus and occasionally produced fistulating tracts through the wall of the organ. Microscopically, multifocal lymphoid nodules were noted in the mucosa and submucosa of the phallus and were associated with extensive granulomatous reaction, intralesional bacteria, and spermatozoa. Mycoplasma spp. were isolated from the phallus of affected and nonaffected birds, and PCR protocols targeting the 16S-23S ribosomal RNA intergenic spacer regions and the RNA polymerase beta subunit gene were performed to identify the isolates. Three distinct species were identified on sequencing and analysis using the National Center for Biotechnology Information basic local alignment search tool: Mycoplasma cloacale , Mycoplasma anseris , and an unknown novel Mycoplasma sp. Additionally, Pasteurella multocida , in combination with other bacteria, was also isolated from the phallic lesions and identified as serotype 3 with a DNA profile of 1511 (National Veterinary Service Laboratory). This is the first report of these Mycoplasma spp. and other bacteria associated with reproductive disease in ganders in the United States.

Characterization of Seven Outbreaks of Hemorrhagic Hepatopathy Syndrome in Commercial Pullets Following the Administration of a Salmonella Enteritidis Bacterin in California.

Between April 2013 and April 2015, seven flocks belonging to three different major commercial egg producers inCalifornia experienced a mild increase in mortality 2 to 3 wk after administration of Salmonella Enteritidis bacterins. Strains of chickens involved were H&N (flock A1, A2, B2, C1, C2, and C3) and Lohmann white (flock B1). Vaccination was administered individually through injection either in the breast muscles or subcutis in the legs between 11 and 18 wk of age in all flocks. Clinical signs ranged from inapparent to lameness, reluctance to walk, greenish diarrhea, and retching-like symptoms. The mortality ranged from 0.16% to 1.38% per week, with the highest peaks occurring usually 2 to 3 wk postvaccination, and then declined rapidly. Postmortem examinations revealed enlarged livers with disseminated hemorrhages and pale foci of necrosis. Also, severe extensive hemorrhages in the intestine, heart, and proventriculus were observed in a few birds. Various degrees of productive, exudative giant cell granulomatous myositis were observed invading deeply the muscles and subcutis at the site of vaccination. The myositis was always associated with optically empty vacuoles positive for neutral lipids by Oil Red O stain. Droplets of Oil Red O material were also noticed in the affected livers and intestines. Congo red stain highlighted the presence of amyloid in moderate to severe amounts in the breast muscles and moderate amounts in livers, spleens, and intestines. Salmonella antigens were detected in the injection sites and livers by immunohistochemical staining. No viruses or toxic substances were recovered from the liver, spleen, intestine, and pectoral muscles, and the few bacteria isolated were interpreted as secondary postmortem invaders. In addition, livers and bile tested for hepatitis E virus were negative by reverse-transcriptase polymerase chain reaction.

The missing large impact craters on Ceres.

Asteroids provide fundamental clues to the formation and evolution of planetesimals. Collisional models based on the depletion of the primordial main belt of asteroids predict 10-15 craters >400 km should have formed on Ceres, the largest object between Mars and Jupiter, over the last 4.55 Gyr. Likewise, an extrapolation from the asteroid Vesta would require at least 6-7 such basins. However, Ceres' surface appears devoid of impact craters >∼280 km. Here, we show a significant depletion of cerean craters down to 100-150 km in diameter. The overall scarcity of recognizable large craters is incompatible with collisional models, even in the case of a late implantation of Ceres in the main belt, a possibility raised by the presence of ammoniated phyllosilicates. Our results indicate that a significant population of large craters has been obliterated, implying that long-wavelength topography viscously relaxed or that Ceres experienced protracted widespread resurfacing.

Cryovolcanism on Ceres.

Volcanic edifices are abundant on rocky bodies of the inner solar system. In the cold outer solar system, volcanism can occur on solid bodies with a water-ice shell, but derived cryovolcanic constructs have proved elusive. We report the discovery, using Dawn Framing Camera images, of a landform on dwarf planet Ceres that we argue represents a viscous cryovolcanic dome. Parent material of the cryomagma is a mixture of secondary minerals, including salts and water ice. Absolute model ages from impact craters reveal that extrusion of the dome has occurred recently. Ceres' evolution must have been able to sustain recent interior activity and associated surface expressions. We propose salts with low eutectic temperatures and thermal conductivities as key drivers for Ceres' long-term internal evolution.

The geomorphology of Ceres.

Analysis of Dawn spacecraft Framing Camera image data allows evaluation of the topography and geomorphology of features on the surface of Ceres. The dwarf planet is dominated by numerous craters, but other features are also common. Linear structures include both those associated with impact craters and those that do not appear to have any correlation to an impact event. Abundant lobate flows are identified, and numerous domical features are found at a range of scales. Features suggestive of near-surface ice, cryomagmatism, and cryovolcanism have been identified. Although spectroscopic analysis has currently detected surface water ice at only one location on Ceres, the identification of these potentially ice-related features suggests that there may be at least some ice in localized regions in the crust.

Cratering on Ceres: Implications for its crust and evolution.

Thermochemical models have predicted that Ceres, is to some extent, differentiated and should have an icy crust with few or no impact craters. We present observations by the Dawn spacecraft that reveal a heavily cratered surface, a heterogeneous crater distribution, and an apparent absence of large craters. The morphology of some impact craters is consistent with ice in the subsurface, which might have favored relaxation, yet large unrelaxed craters are also present. Numerous craters exhibit polygonal shapes, terraces, flowlike features, slumping, smooth deposits, and bright spots. Crater morphology and simple-to-complex crater transition diameters indicate that the crust of Ceres is neither purely icy nor rocky. By dating a smooth region associated with the Kerwan crater, we determined absolute model ages (AMAs) of 550 million and 720 million years, depending on the applied chronology model.

Patterns of naturally occurring restriction map variation, dopa decarboxylase activity variation and linkage disequilibrium in the Ddc gene region of Drosophila melanogaster.

Forty-six second-chromosome lines of Drosophila melanogaster isolated from five natural populations were surveyed for restriction map variation in a 65-kb region surrounding the gene (Ddc) encoding dopa decarboxylase (DDC). Sixty-nine restriction sites were scored, 13 of which were polymorphic. Average heterozygosity per nucleotide was estimated to be 0.005. Eight large (0.7-5.0 kb) inserts, two small inserts (100 and 200 bp) and three small deletions (100-300 bp) were also observed across the 65-kb region. We see no evidence for a reduction in either nucleotide heterozygosity or insertion/deletion variation in the central 26-kb segment containing Ddc and a dense cluster of lethal complementation groups and transcripts (greater than or equal to 9 genes) compared to that seen in the adjacent regions (totaling 39 kb) in which only a single gene and transcript has been detected, or to that observed for other gene regions in D. melanogaster. The distribution of restriction site variation shows no significant departure from that expected under an equilibrium neutral model. However insertions and deletions show a significant departure from neutrality in that they are too rare in frequency, consistent with them being deleterious on average. Significant linkage disequilibrium among variants exists across much of the 65-kb region. Lower regional rates of recombination combined with the influence of polymorphic chromosomal inversions, rather than epistatic selection among genes in the dense cluster, probably are sufficient explanations for the creation and/or maintenance of the linkage disequilibrium observed in the Ddc region. We have also assayed adult DDC enzyme activity in these same lines. Twofold variation in activity among lines is observed within our sample. Significant associations are observed between level of DDC enzyme activity and restriction map variants. Surprisingly, one line with a 5.0-kb insert within an intron and one line with a 1.5-kb insert near the 5' end of Ddc each show normal adult DDC activities.

Maize mitochondrial plasmid S-1 sequences share homology with chloroplast gene psbA.

The linear, 6397-base pair (bp), mitochondrial S-1 DNA molecule from maize contains a 420-bp segment that is homologous with the chloroplast gene (psbA) that codes for the quinone binding protein of photosystem II. This is the first report of a chloroplast sequence in a naturally occurring viral-like or plasmid DNA. The complete sequence of the S-1 chloroplast segment has been compared with homologous regions of six different chloroplast genes. The S-1 segment has diverged from the other genes both by length mutation and base substitution. Several of the length mutations are exact adjacent tandem duplications of 4 and 5 bp similar to "footprints" left after excision of transposable elements in maize nuclear DNA.

Molecular population genetics of the alcohol dehydrogenase gene region of Drosophila melanogaster.

Variation in the DNA restriction map of a 13-kb region of chromosome II including the alcohol dehydrogenase structural gene (Adh) was examined in Drosophila melanogaster from natural populations. Detailed analysis of 48 D. melanogaster lines representing four eastern United States populations revealed extensive DNA sequence variation due to base substitutions, insertions and deletions. Cloning of this region from several lines allowed characterization of length variation as due to unique sequence insertions or deletions [nine sizes; 21-200 base pairs (bp)] or transposable element insertions (several sizes, 340 bp to 10.2 kb, representing four different elements). Despite this extensive variation in sequences flanking the Adh gene, only one length polymorphism is clearly associated with altered Adh expression (a copia element approximately 250 bp 5' to the distal transcript start site). Nonetheless, the frequency spectra of transposable elements within and between Drosophila species suggests they are slightly deleterious. Strong nonrandom associations are observed among Adh region sequence variants, ADH allozyme (Fast vs. Slow), ADH enzyme activity and the chromosome inversion ln(2L)t. Phylogenetic analysis of restriction map haplotypes suggest that the major twofold component of ADH activity variation (high vs. low, typical of Fast and Slow allozymes, respectively) is due to sequence variation tightly linked to and possibly distinct from that underlying the allozyme difference. The patterns of nucleotide and haplotype variation for Fast and Slow allozyme lines are consistent with the recent increase in frequency and spread of the Fast haplotype associated with high ADH activity. These data emphasize the important role of evolutionary history and strong nonrandom associations among tightly linked sequence variation as determinants of the patterns of variation observed in natural populations.