A unified call to action from Australian nursing and midwifery leaders: ensuring that Black lives matter.

Nurses and midwives of Australia now is the time for change! As powerfully placed, Indigenous and non-Indigenous nursing and midwifery professionals, together we can ensure an effective and robust Indigenous curriculum in our nursing and midwifery schools of education. Today, Australia finds itself in a shifting tide of social change, where the voices for better and safer health care ring out loud. Voices for justice, equity and equality reverberate across our cities, our streets, homes, and institutions of learning. It is a call for new songlines of reform. The need to embed meaningful Indigenous health curricula is stronger now than it ever was for Australian nursing and midwifery. It is essential that nursing and midwifery leadership continue to build an authentic collaborative environment for Indigenous curriculum development. Bipartisan alliance is imperative for all academic staff to be confident in their teaching and learning experiences with Indigenous health syllabus. This paper is a call out. Now is the time for Indigenous and non-Indigenous nurses and midwives to make a stand together, for justice and equity in our teaching, learning, and practice. Together we will dismantle systems, policy, and practices in health that oppress. The Black Lives Matter movement provides us with a 'now window' of accepted dialogue to build a better, culturally safe Australian nursing and midwifery workforce, ensuring that Black Lives Matter in all aspects of health care.

A new bamboo-feeding species of Kaochiaoja Tao (Hemiptera: Aphididae) from India.

A new species of the genus Kaochiaoja Tao 1963, K. sikkimensis sp. n., was collected on Phyllostachys sp. (Poaceae) from Upper Tadong area of Gangtok, East Sikkim, India. Apterous and alate viviparae of this species are described, illustrated and discussed in comparison with the only other nominal species in this genus.

Distribution of common genotypes of Myzus persicae (Hemiptera: Aphididae) in Greece, in relation to life cycle and host plant.

Microsatellite genotyping was used to identify common clones in populations of the Myzus persicae group from various hosts and regions in mainland Greece and southern Italy and to compare their distribution and occurrence on tobacco and other crops. Common clones were defined as genotypes collected at more than one time or in more than one population; and, therefore, unlikely to be participating in the annual sexual phase on peach. Sixteen common genotypes were found, accounting for 49.0% of the 482 clonal lineages examined. Eight of these genotypes were subjected, in the laboratory, to short days and found to continue parthenogenetic reproduction, i.e. they were anholocyclic. Four of the six commonest genotypes were red, and one of these accounted for 29.6% of the samples from tobacco and 29.4% of those from overwintering populations on weeds. All six commonest genotypes were found on weeds and five of them both on tobacco and on other field crops. In mainland Greece, the distribution of common clones corresponded closely with that of anholocyclic lineages reported in a previous study of life cycle variation. Common genotypes were in the minority in the commercial peach-growing areas in the north, except on weeds in winter and in tobacco seedbeds in early spring, but predominated further south, away from peach trees. This contrasts with the situation in southern Italy, reported in a previous paper, where peaches were available for the sexual phase, yet all samples from tobacco were of common genotypes.

Morphological discrimination of Aphis gossypii (Hemiptera: Aphididae) populations feeding on Compositae.

Aphis gossypii Glover is a polyphagous aphid pest with a worldwide distribution. However, there is evidence that on a global scale the name A. gossypii is being applied to a number of forms with different life cycles and/or host-plant associations. Morphometric variation of A. gossypii samples from crops and non-cultivated plants in many parts of the world was examined, to determine whether this variation is correlated with the hosts from which the aphids originated. Samples of A. gossypii were collected from Cucurbitaceae and Malvaceae in Europe, and from Compositae in various parts of the world. Morphometric data for 13 parameters measured from 97 clonal lineages (728 specimens) and 27 field-collected samples (313 specimens) were analysed by a series of canonical variates analyses, using the field sample/clonal lineage as grouping factor. Clonal lineages were reared on a common host in controlled conditions to standardize the effect of host and environment on morphology. The analyses provided a clear morphometric separation of the aphids originating from Compositae and those collected on Cucurbitaceae and Malvaceae, regardless of the geographical origin of the aphids and the host plant on which they were reared. This indicates that within A. gossypii there are two widely distributed host races or subspecies with different plant family associations. The taxonomic implications are discussed.

Co-existence of different host-adapted forms of the Myzus persicae group (Hemiptera: Aphididae) in southern Italy.

Multivariate morphometric analysis (method of canonical variates) was used to compare 38 parthenogenetic lineages and three field collections of aphids of the Myzus persicae (Sulzer) group sampled on peach and tobacco in the Caserta region of southern Italy. Comparisons were also made with the morphology of lineages collected on peach in Lehonia, in central eastern Greece away from tobacco-growing regions, and on tobacco in Naphplion, in southern Greece. The lineages were measured after parthenogenetic rearing for one to three generations on the same host (potato) under constant conditions. As in previous work, the multivariate morphometric approach separated the aphids from peach from those feeding on tobacco. The life cycle category of the lineages was also examined. Almost all the lineages from peach in Caserta were holocyclic, yet the lineages from tobacco in the same region were unable to produce sexual morphs. The results suggest that tobacco-adapted and non-tobacco-adapted forms co-exist in the same region in southern Italy, not only because they colonize different host plants, but also because they have different life cycles. This is in complete contrast to the situation in peach-growing areas of northern Greece, and shows that the ecology and population structure of M. persicae is different in neighbouring counties of the Mediterranean area, even where climatic conditions and cultivated crops are similar.

Life cycle variation of Myzus persicae (Hemiptera: Aphididae) in Greece.

During the years 1995-1999 the life cycle category of 2797 clones of Myzus persicae (Sulzer) was examined. The clones originated from primary and secondary hosts from different localities of North and Central Greece and the island of Crete in the south. Four different overwintering life cycle strategies were found that have also been described for M. persicae and other heteroecious species previously. A geographical variation was found in the proportion of holocyclic clones from tobacco and other secondary hosts associated with the abundance of the primary host in the sampling regions. In Central Macedonia, around the main peach-growing regions, the proportion of holocyclic clones was mostly above 50% and in some cases reached 100%. In localities of East Macedonia, holocyclic clones were also frequent. On the other hand, further south or in north-eastern Greece, where peach is not common, the proportion of holocyclic clones varied between 0 and 33%. Fifty seven percent of examined anholocyclic clones produced males under short day conditions, suggesting that androcyclic clones in Greece represent an important factor of genetic variability. Intermediate clones were sampled from all host-plants but at low frequencies (3.6% of total examined clones and 6.9% of non-holocyclic ones). Moreover, a regional variation was found in different colour forms feeding on tobacco plants. Red clones were predominant in regions where aphids overwinter parthenogenetically on weeds or winter crops. However, almost all clones from the primary host were green. The ecological aspects of life cycle variation are discussed.

Microsatellite variation in cyclically parthenogenetic populations of Myzus persicae in south-eastern Australia.

We examined the population structure of the introduced aphid, Myzus persicae collected mainly from its primary host, Prunus persica, in south-east Australia. Myzus persicae has been present in Australia since at least 1893. Samples were collected in the spring of 1998 from two mainland and three Tasmanian localities and isofemale lines were established in the laboratory. The reproductive mode (life cycle), karyotype and 17-locus microsatellite genotype of each clone were determined. All populations showed significant population differentiation (F(ST) 0.058-0.202) even over small geographic distances (<50 km). All clones were karyotypically normal except for a subset of clones from one site that was exposed to the carbamate insecticide, Pirimor, the week prior to sampling. Those clones were heterozygous for an autosomal 1,3 translocation frequently associated in M. persicae with insecticide resistance. In contrast to other loci and despite being on different chromosomes, loci myz2(A) and M55(A) showed general and significant linkage disequilibrium. These loci may be affected by epistatic selection. We discuss the observed high clonal diversity, moderate but significant population differentiation, general conformance to Hardy-Weinberg equilibria and low linkage disequilibria with particular focus on the global population biology of M. persicae.

Host-correlated morphological variation of Myzus persicae (Hemiptera: Aphididae) populations in Greece.

Morphological variation in nine characters of 157 clones of Myzus persicae (Sulzer) was examined by multivariate analysis. The clones were collected from peach, Prunus persica, the primary host and the secondary hosts tobacco, Nicotiana tabacum, cabbage, Brassica oleracea, sugarbeet, Beta vulgaris and pepper Capsicum annuum. The 156 clones originated from various regions of Greece, both in the north, where a large part of the population has an annual bisexual generation on peach, and in more southerly regions, where populations are predominantly unisexual. One clone was collected from tobacco in Caserta, Italy. All clones were laboratory-reared on potato. Canonical variate analysis, hierarchical cluster analysis and a non-parametric classification tree method both revealed morphological differences associated with the host-plant on which they were collected. The scores of the first two canonical variates separated the tobacco-feeding clones from those originating from other secondary host-plants. However, in tobacco-growing areas the tobacco-feeding form predominated in spring populations on peach, and was sometimes found on other secondary hosts. In addition, using cluster analysis, the clones from tobacco which were sampled in the most southeasterly region showed a relatively large phenotypic distance from those collected further north and west. Moreover, clonal phenotypes were affected both by host plant and by long-term parthenogenetic rearing. However, in spite of these effects, the tobacco form was generally distinguishable from aphids originating from other hosts, indicating that the difference must have a genetic basis. In separate analyses of the clones originating from secondary hosts no association was found between morphology and either life cycle category or colour. Discriminant analysis showed that 89% of 1723 specimens could be correctly classified into the two groups.

High diversity of structurally heterozygous karyotypes and rDNA arrays in parthenogenetic aphids of the genus Trama (Aphididae: Lachninae).

Karyotypes of permanently parthenogenetic aphids of three species of the genus Trama show great diversity, particularly in the number and distribution of chromosomal elements containing highly repetitive sequences. Sampling at only a few sites in southern England, chromosome number varied from 14 to 23 in T. troglodytes, 9-12 in T. caudata and 10-14 in T. maritima, with some colonies having individuals of more than one karyotype. This variation was paralleled by differences in the number and distribution of rDNA arrays revealed by in situ hybridization. This high intraspecific karyotype diversity contrasts with very low genetic diversity in the same populations, suggesting rapid karyotype evolution. Although T. troglodytes feeds on many species of composite plants there was no evidence of any karyotype-associated host race formation.

Evaluation of the dimensional changes and surface roughness of gold crowns cast with rapidly prepared phosphate-bonded investment: a pilot study.

STATEMENT OF PROBLEM: Accelerated bench-set and burnout schedules are used with little knowledge of the effect acceleration has on clinical factors determining casting success. PURPOSE: This pilot study investigated the effect of 2 rapid mold preparation schedules on full crown castings by comparing size, margin sharpness, and surface roughness. MATERIAL AND METHODS: Three groups of 10 crowns were cast with a type III gold alloy. All crowns were nominally identical, only their mold preparation schedules differed. Two groups used accelerated schedules; the third group was cast using a conventional schedule. Group comparisons were based on direct microscopic measurements of crown diameters (x50 magnification), and surface roughness was measured. Margin sharpness was judged by amount of marginal length lost in the axial direction as a result of the casting process. RESULTS: Measured crown diameters, indexing size for the 3 groups, were not significantly different. Crowns made with the conventional schedule had greater surface roughness, and better margin sharpness or length. CONCLUSION: Crowns were successfully cast using accelerated mold preparation techniques and considerable time was saved, but a small loss of margin length or fineness was observed.

Inheritance and meiotic behaviour of a de novo chromosome fusion in the aphid Myzus persicae (Sulzer).

A de novo tandem fusion between autosomes 2 and 3 (A2+3), arising in the course of laboratory crosses of sexual morphs of two clones of the aphid Myzus persicae, was stable through more than 180 generations of parthenogenetic (clonal) reproduction. Studies of its inheritance through the sexual phase, and segregation from an amplified esterase marker gene, showed that crossing over occurred during oogenesis, but not in spermatogenesis, confirming previous cytological observations. Only a small number of progeny resulted from attempts at selfing fusion heterozygotes, and none of these was homozygous for the fusion. A2+3 paired in parallel alignment with the separate A2 and A3 to form a trivalent at prophase I of spermatogenesis. Fusion heterozygotes had a segregation problem at anaphase I of meiosis, A2+3 forming a chromatin bridge between the daughter spermatocytes in about 42% of dividing cells, which could be attributed to alternate orientation in the trivalent (A2 and A3 paired with opposite sides of A2+3) in the preceding metaphase I. Males heterozygous for an A2 dissociation were also studied and found to have much less of a segregation problem, despite showing similar orientation patterns at metaphase I. Possible reasons for this difference and the significance of the findings in relation to karyotype evolution in aphids are discussed.

Wingless, decapentaplegic and EGF receptor signaling pathways interact to specify dorso-ventral pattern in the adult abdomen of Drosophila.

Adult abdominal segments of Drosophila are subdivided along the dorso-ventral axis into a dorsal tergite, a ventral sternite and ventro-lateral pleural cuticle. We report that this pattern is largely specified during the pupal stage by Wingless (Wg), Decapentaplegic (Dpp) and Drosophila EGF Receptor (DER) signaling. Expression of wg and dpp is activated at the posterior edge of the anterior compartment by Hedgehog signaling. Within this region, wg and dpp are expressed in domains that are mutually exclusive along the dorso-ventral axis: wg is expressed in the sternite and medio-lateral tergite, whereas dpp expression is confined to the pleura and the dorsal midline. Neither gene is expressed in the lateral tergite. Shirras and Couso (1996, Dev. Biol. 175, 24-36) have shown that tergite and sternite cell fates are specified by Wg signaling. We find that DER acts synergistically with Wg to promote tergite and sternite identities, and that Wg and DER activities are opposed by Dpp signaling, which promotes pleural identity. Wg and Dpp interact antagonistically at two levels. First, their expression is confined to complementary domains by mutual transcriptional repression. Second, Wg and Dpp compete directly with one another by exerting opposite effects on cell fate. DER signaling does not affect the expression of wg or dpp, indicating that it interacts with Wg and Dpp at the level of cell fate determination. Within the tergite, the requirements for Wg and DER function are roughly complementary: Wg is required mainly in the medial region, whereas DER is most important laterally. Finally, we show that Dpp signaling at the dorsal midline controls dorso-ventral patterning within the tergite by promoting pigmentation in the medial region.

Cubitus interruptus is necessary but not sufficient for direct activation of a wing-specific decapentaplegic enhancer.

In Drosophila, the imaginal discs are the primordia for adult appendages. Their proper formation is dependent upon the activation of the decapentaplegic (dpp) gene in a stripe of cells just anterior to the compartment boundary. In imaginal discs, the dpp gene has been shown to be activated by Hedgehog signal transduction. However, an initial analysis of its enhancer region suggests that its regulation is complex and depends upon additional factors. In order to understand how multiple factors regulate dpp expression, we chose to focus on a single dpp enhancer element, the dpp heldout enhancer, from the 3' cis regulatory disc region of the dpp locus. In this report, we present a molecular analysis of this 358 bp wing- and haltere-specific dpp enhancer, which demonstrates a direct transcriptional requirement for the Cubitus interruptus (Ci) protein. The results suggest that, in addition to regulation by Ci, expression of the dpp heldout enhancer is spatially determined by Drosophila TCF (dTCF) and the Vestigial/Scalloped selector system and that temporal control is provided by dpp autoregulation. Consistent with the unexpectedly complex regulation of the dpp heldout enhancer, analysis of a Ci consensus site reporter construct suggests that Ci, a mediator of Hedgehog transcriptional activation, can only transactivate in concert with other factors.

Relationship between amount of esterase and gene copy number in insecticide-resistant Myzus persicae (Sulzer).

Overproduction of the insecticide-degrading esterases, E4 and FE4, in peach-potato aphids, Myzus persicae (Sulzer), depends on both gene amplification and transcriptional control, the latter being associated with changes in DNA methylation. The structure and function of the aphid esterase genes have been studied but the determination of their copy number has proved difficult, a common problem with gene amplification. We have now used a combination of pulsed-field gel electrophoresis and quantitative competitive PCR to determine relative esterase gene copy numbers in aphid clones with different levels of insecticide resistance (R1, R2 and R3). There are approx. 4-fold increases between susceptible, R1, R2 and R3 aphids, reaching a maximum of approx. 80 times more genes in R3; this gives proportionate increases in esterase protein relative to susceptible aphids. Thus there is no overexpression of the amplified genes, in contrast with what was thought previously. For E4 genes, the loss of 5-methylcytosine is correlated with a loss of expression, greatly decreasing the amount of enzyme relative to the copy number.

The effect of sprue design on the marginal accuracy of titanium castings.

The purpose of this study was to measure the effects of sprue number and position on cast titanium crown margins. Twenty-four complete veneer crown wax patterns were fabricated on a stainless steel die with a 30 degrees bevel finish line. Twelve wax patterns were sprued with one 8-gauge wax sprue and the remaining 12-gauge double sprued. All patterns were invested with a phosphate bonded investment. Castings were made with a titanium casting machine following the manufacturer's instructions and using commercially pure titanium (> 99.5%) ingots. The castings were than carefully cleansed and the margins were examined with indirect impression technique. Data were analysed with an ANOVA and the Student's t-test with confidence level at 95%. The results revealed that the marginal discrepancy for the double sprueing group (32.1 +/- 12.8 microm) has significantly less discrepancy (P < 0.001) than the single sprueing group (49.8 +/- 16.4 microm). There was no statistically significant differences in marginal discrepancy between locations within the sprueing techniques (P > 0.05). An improvement in the degree of casting accuracy of titanium crown was indicated by the double sprue design used in this investigation.

A 169-base pair tandem repeat DNA marker for subtelomeric heterochromatin and chromosomal rearrangements in aphids of the Myzus persicae group.

Numerous copies of a 169-base pair DNA sequence (Myzus persicae group repeat; MpR) occur at subtelomeric locations on all chromosomes of three members of the Myzus persicae species group (Myzus persicae, M. antirrhinii, M. certus). MpR occurs in large tandem arrays at both ends of all autosomes of the standard 2n = 12 karyotype, and near one end of the X chromosome (the end opposite to the nucleolar organizer) and is estimated to make up about 5% of the genome (a total of about 200000 copies). Locations of MpR were compared in various karyotypes to determine the likely nature of the rearrangements (fusions, dissociations, translocations) that are found in this species group which, like other Hemiptera, has holocentric chromosomes that are devoid of morphological markers. Aphid clones heterozygous for autosome dissociations do not have any detectable MpR at 'new' chromosome ends, indicating that this sequence is not involved in 'capping' of chromosomes. However, a clone with a de novo autosome fusion had an interstitial block of MpR marking the point of fusion, and clones heterozygous for an autosomal 1,3 translocation had MpR from autosome 1 translocated to a new site on autosome 3. The isolation from M. antirrhinii of the telomeric repeat TTAGG, which is found in several insect groups, is also reported.

Orientation of the 'stretched' univalent X chromosome during the unequal first meiotic division in male aphids.

In situ hybridization was used to label the ends of the X chromosomes of two aphid species, Myzus persicae and Amphorophora tuberculata, in order to study the peculiar behaviour and orientation of the univalent X in aphid spermatogenesis. Anaphase I begins with the long axis of the X chromosome at right angles to the spindle and its two chromatids closely associated, but as the division proceeds the chromatids separate along most of their lengths, retaining only a midway connection as the X chromosome becomes stretched on the spindle. Both ends of one chromatid move towards one pole, while both ends of the other chromatid move towards the other pole. However, the midway connection is retained and the whole X chromosome eventually passes into one daughter cell. This form of X chromosome behaviour is common to all aphids and therefore presumably dates back to the Permian. It is independent of the type of meiosis, which in aphids can be 'normal' (reductional first division) or 'inverted' (reductional second division).

Vertical food web interactions: evolutionary patterns and driving forces.

edited by K. Dettner, G. Bauer and W. Völkl, Ecological Studies Vol. 130, Springer-Verlag, 1997. pound76.00 (xxi+390 pages) ISBN 3 540 62561 5.