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Introduction: As of 2020, the U.S. Antarctic meteorite program has collected >23,500 meteorites. The systematic collection methods employed have provided meteorites of >40 types, many of which are the first of their type ever recognized. One of the early drivers for characterization of the entire U.S. Antarctic collection was to allow statistical comparisons. Early assessments examined mass distributions and the relative frequency of meteorite types as well as comparisons to a defined set of modern falls [1-3]. Using these statistics [4-6] argued that the flux of H chondrites changed over time. [7] used model size distributions to deconstruct the contribution of wind movement, meteorite supply and search losses to the Antarctic collection. Mass-based statistics [8] and size distribution comparisons were examined by [8,9]. [10,11] investigated various statistics, including comparison with modern falls/Saharan finds. [12, 13] discuss geospatial statistics. [14] provides a comprehensive overview of the statistics of the Antarctic collections for the first 35 seasons of U.S. collection by ANSMET. Here we build upon that assessment and that from [15]. Statistics of the U.S. Collection: One of the most important questions surrounding the collection of meteorites in Antarctica is whether the collection procedure is recovering a representative sample of what is actually present at each site. In >40 seasons of searching, we have collected samples from 50 named field sites. Sixteen sites have produced >100 meteorites, and nine have produced >1000 [14]. Field areas with smaller populations (<1000) appear to have an overabundance of unusual meteorite types. However, field sites from which >1000 meteorites have been collected have type populations that converge at approximately 90% ordinary chondrites (OC). Antarctic meteorite populations show interesting trends when comparing certain classes and sizes of falls and hot desert populations. One of these shows large numbers of small samples of OCs, pointing to the possibility of preserved showers that may not have been taken into account in the overall numbers of parent meteorites [16]. These OC populations, combined with the unresolved issue of meteorite pairing, have a significant impact on a comprehensive statistical evaluation of the Antarctic meteorite population. Another visible trend between Antarctic meteorites, worldwide falls and hot desert meteorites is that there is a startling under-abundance of iron meteorites with low masses in the Antarctic collection [17]. Based on a theory that there should be a layer of iron meteorites stranded below the ice, [17] searched for clues to where these meteorites may be. Another obvious absence is CI chondrites. There may be a strength bias, but this is poorly understood as CMs are recovered and irons aren't overepresented. Mass Distribution: An alternative approach is to examine the cumulative mass distribution of a population relative to the number of meteorites represented. [1,14,15,18] point out that the mass of meteorites found in Antarctic field sites peaks at ~10g, while those of modern witnessed falls peak at ~5kg. Saharan meteorite peak at ~300g. As discussed by [18,19], systematic collection of meteorites in Antarctica and elsewhere recovers more small meteorites than do random searches. This remains logical in that small (<2 cm) meteorites are much easier to spot on Antarctic ice than they are in non-Antarctic locations. [18,19] show that the number of meteorites collected in various locations (including falls) has a wide variation when compared with total mass. However, if these meteorites were all thoroughly examined and put into pairing groups, the number of meteorites after pairing would certainly decrease, and if more small modern falls were actually recovered [18] this discrepancy would be minimized. When looking at total mass between Saharan and Antarctic meteorites, it can be seen that while there are ~3x fewer Saharan meteorites (~16000 classified) vs. Antarctics (~47000) [20], the mass of Saharan meteorites (~31.5 metric tons) vs. Antarctics (~6.1 metric tons) is ~5x higher. The major difference between these two populations is that the Antarctic meteorites, in all collections worldwide, are available to science. While we may never completely understand all mechanisms that impact the population of meteorites collected in Antarctica, we can be confident that Antarctic Meteorite Programs have exceeded expectations for providing a broad sampling of Solar System materials and have had a significant impact on meteorite science. [ABSTRACT FROM AUTHOR]

Primary afferent unmyelinated nerves modulate the inflammatory response to injury through a process known as neurogenic inflammation. The undecapeptide Substance P is contained in many of these nerves and therefore may be an important mediator of the response. Treatment of neonatal rats with capsaicin permanently destroys primary afferent unmyelinated nerves and depletes (he skin and other organs of Substance P. These animals have a reduced capacity to mount an inflammatory response to injury. We examined the ability of Substance P to chem-attract neutrophils from normal rats and rats treated as neonates with capsaicin. Substance P was shown to cause normal rat neutrophils to chemotact at an optimum concentration of 5 x 10 -'' M. Equivalent chemotaxis was observed in neutrophils from rats retreated as neonates with capsaicin. Substance P did not increase chemokinesis. These in vitro results support the view that the reduced neurogenic inflammatory response seen in capsaicin-retreated rats is not due to a direct toxic effect of capsaicin on neutrophils, but may be due to a decreased availability of neurally derived Substance P at the site of injury. [ABSTRACT FROM AUTHOR]

Eungella's wet forests are home to a number of stream-breeding frogs including three species endemic to the Eungella region: the Eungella dayfrog (Taudactylus eungellensis), Eungella tinkerfrog (T. liemi), and northern gastric brooding frog (Rheobatrachus vitellinus). During the mid-1980s, T. eungellensis and R. vitellinus suffered dramatic population declines attributable to amphibian chytridiomycosis, a disease caused by the amphibian chytrid fungus (Batrachochytrium dendrobatidis or Bd). While surveys in the late 1980s failed to locate T. eungellensis or R. vitellinus, populations of the former were located on a handful of streams surveyed by researchers in the mid-tolate 1990s. Between January 2000 and November 2015, additional surveys targeting these and other wet forest frog species were conducted at 114 sites within Eungella National Park and adjoining areas of State Forest. During these surveys, we located T. eungellensis at many more sites than surveys in the 1990s. Abundances of T. eungellensis at these sites were typically low, however, and well below abundance levels prior to declines in the mid-1980s. As with surveys in the 1990s, T. eungellensis was scarce at high-elevation sites above 600 metres altitude. Numbers of this species do not appear to have increased significantly since the mid-1990s, suggesting recovery of T. eungellensis populations is occurring slowly, at best. In contrast with T. eungellensis, T. liemi was frequently recorded at high-elevation sites, albeit at low densities. As with previous surveys, surveys during 2000-2015 were unsuccessful in locating R. vitellinus. Further frog surveys and monitoring (including disease surveillance) are needed to better assess the status of stream frogs at Eungella, and to understand the influence of Bd on the abundance and distribution of threatened stream-dwelling frogs at Eungella. [ABSTRACT FROM AUTHOR]

Waddycephalus is an understudied genus of pentastomids native to Australia and south-east Asia. The genus was recognized in 1922 but there has been little research on these pentastomid tongue worms over the last century. A few observations suggest a complex life cycle through 3 trophic levels. We aimed to add knowledge to the Waddycephalus life cycle in woodland habitats in the Townsville region of north-east Australia. We used camera trapping to identify the most likely first-intermediate hosts (coprophagous insects), we conducted gecko surveys to identify multiple new gecko intermediate host species and we dissected road-killed snakes to identify additional definitive hosts. Our study paves the way for further research into the intriguing life cycle of Waddycephalus , investigation of spatial variation in prevalence and impacts of the parasite on host species.

Aims: To describe a body of Māori translational research responses that challenge colonialised systems., Methods: To delineate and link ongoing Kaupapa Māori and Māori-led translational research., Results: He Tapu Te Whare Tangata explores human papilloma virus (HPV) screening. Te Hā o Whānau presents a culturally responsive framework of maternity care. E Hine describes young Māori mothers' experiences of Hapū Ora. Severe Acute Maternal Morbidity (SAMM) and SAMM Kids identify opportunities to improve avoidable morbidity. He Tamariki Kokoti Tau - Babies born prematurely, is a qualitative study of Māori experiences of preterm birth. He Tamariki Kokoti Tau - Tackling Preterm, is a quantitative analysis. He Korowai Manaaki is a wraparound maternity pathway. Whānau Manaaki - Methamphetamine aims to reduce the impact of methamphetamine. Calls for action reflect shared desires for system transformation., Conclusion: We lay the wero (challenge) down to all to transform our current systems. Action is needed! Abbreviations : HPV: human papilloma virus, SAMM: severe acute maternal morbidity, ICU: intensive care unit, HDU: high dependency unit, RCT: randomised controlled trial, HQSC: Health Quality and Safety Commission., Competing Interests: The authors report there are no conflicts of interest to declare., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Background: Antibody Fc-driven engagement of macrophages is critical for evoking cellular activation and effector functions and influencing tumour-associated macrophage (TAM) recruitment. We previously reported that IgE class antibodies promote restriction of cancer growth in rodent models associated with significant TAM infiltration. However, the human macrophage-associated IgE-Fc Receptor (FcεR) axis remains unexplored. We investigated the effects of anti-tumour IgE stimulation on human macrophage activation., Methods: Human blood monocyte-differentiated quiescent (M0), classically-(M1) and alternatively-(M2) activated macrophages were crosslinked with IgE and polyclonal antibodies to mimic immune complex formation. We examined surface marker expression, cytokine secretion, protein kinase phosphorylation and gene expression in IgE-stimulated macrophages and IgE antibody-dependent macrophage-mediated cytotoxicity (ADCC) against tumour cells., Findings: A proportion (40%) of M2 and (<20%) M0 and M1 macrophages expressed the high-affinity IgE receptor FcεRI. IgE crosslinking triggered upregulation of co-stimulatory CD80, increased TNFα, IFNγ, IL-1β, IL-12, IL-10, IL-13, CXCL9, CXCL11 and RANTES secretion by M0 and M2 and additionally enhanced MCP-1 by M2 macrophages. IgE-stimulated M1 macrophages retained secretion of pro-inflammatory cytokines. IgE crosslinking enhanced the FcεRI-dependent signalling pathway, including phosphorylation of the Lyn kinase, ERK1/2 and p38 in M2 macrophages and upregulated Lyn gene expression by M1 and M2 macrophages. Anti-tumour IgE engendered ADCC of cancer cells by all macrophage subsets., Interpretation: IgE can engage and re-educate alternatively-activated macrophages towards pro-inflammatory phenotypes and prime all subsets to mediate anti-tumour functions. This points to IgE-mediated cascades with potential to activate immune stroma and may be significant in the clinical development of strategies targeting tumour-resident macrophages., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Species interactions can determine range limits, and parasitism is the most intimate of such interactions. Intriguingly, the very conditions on range edges likely change host-parasite dynamics in nontrivial ways. Range edges are often associated with clines in host density and with environmental transitions, both of which may affect parasite transmission. On advancing range edges, founder events and fitness/dispersal costs of parasitism may also cause parasites to be lost on range edges. Here we examine the prevalence of three species of parasite across the range edge of an invasive gecko, Hemidactylus frenatus, in northeastern Australia. The gecko's range edge spans the urban-woodland interface at the edge of urban areas. Across this edge, gecko abundance shows a steep decline, being lower in the woodland. Two parasite species (a mite and a pentastome) are coevolved with H. frenatus, and these species become less prevalent as the geckos become less abundant. A third species of parasite (another pentastome) is native to Australia and has no coevolutionary history with H. frenatus. This species became more prevalent as the geckos become less abundant. These dramatic shifts in parasitism (occurring over 3.5 km) confirm that host-parasite dynamics can vary substantially across the range edge of this gecko host.

The potential for nonembryonic cells to promote differentiation of neuronal cells has therapeutic implications for regeneration of neurons damaged by stroke or injury and avoids many ethical and safety concerns. The authors have assessed the capacity of human umbilical tissue-derived cells (hUTC) and human mesenchymal stromal cells (hMSC) to enhance differentiation of rodent hippocampal neurons. Co-culture of hippocampal cells with hUTC or hMSC in transwell inserts for 3 days resulted in increase of several dendritic parameters including the number and length of primary dendrites. The effect of hUTC or hMSC on dendritic maturation was only apparent on neurons grown for 2 weeks in vitro prior to co-culture. Changes in dendritic morphology in the presence of hUTC were also accompanied by increased expression of the presynaptic marker synaptotagmin and the postsynaptic marker postsynaptic density protein 95 kDa (PSD95) suggesting that there may also be an increase in the number of synapses formed in the presence of hUTC. The effect of hUTC and hMSC on hippocampal cells in co-culture was comparable to those induced by treatment with recombinant human brain-derived neurotrophic factor (BDNF) implying that a similar factor may be released from hUTC or hMSC. Analysis of hUTC-conditioned medium by ELISA demonstrated that BDNF was indeed secreted. An antibody that blocks the actions of BDNF partially inhibited the actions of hUTC on dendritic morphology suggesting that BDNF is at least one of the factors secreted from the cells to promote dendritic maturation. These results indicate that hUTC secrete biologically active BDNF, which can affect dendritic morphology., (Copyright © 2011 Wiley Periodicals, Inc.)

Blocky fragments of aegirine-augite trachyte (with accompanying icerafted gravels.) were recovered from the upper slopes of Kodiak Seamount in several dredge hauls. An alkali basalt pillow segment was also dredged from a moatlike depression, at a depth of 5000 meters, near the west base of the seamount. These retrievals confirm the volcanic origin of Kodiak Seamount and further support the view of Engel, Engel, and Havens that the higher elevations of seamounts are composed of alkali basalts or related variants.