Martian pedestal craters: Marginal sublimation pits implicate a climate-related formation mechanism

Pedestal craters on Mars are defined by an outward-facing scarp forming a plateau perched tens of meters above the surrounding terrain. Their origin has been attributed to impact armoring of the surface and subsequent removal of inter-crater terrain by either eolian deflation or sublimation of an ice-rich substrate. We identified 2696 pedestal craters between 60N and 60S latitude; 98% are poleward of 33N and 40S. The majority of pedestal crater margins are smoothly sloped, but 3%, concentrated in Utopia Planitia and Malea Planurn, display distinctive marginal pits. These pedestal crater scarps are anomalously tall (usually >80-100 m) and the pits resemble sublimation depressions seen on Earth and elsewhere on Mars, providing evidence for sublimation of volatiles in the scarp, where the armored surface has tapered. The pitted scarps provide insight into the origin of the general pedestal crater population, favoring formation via deposition of a volatile-rich substrate, impact armoring, and sublimation of intervening volatiles. Crater densities and overlapping pedestal craters suggest multiple periods of emplacement and loss of these climate-related, latitude-dependent deposits throughout the Amazonian

Projected future climatic forcing on the global distribution of vegetation types

Most emissions scenarios suggest temperature and precipitation regimes will change dramatically across the globe over the next 500 years. These changes will have large impacts on the biosphere, with species forced to migrate to follow their preferred environmental conditions, therefore moving and fragmenting ecosystems. However, most projections of the impacts of climate change only reach 2100, limiting our understanding of the temporal scope of climate impacts, and potentially impeding suitable adaptive action. To address this data gap, we model future climate change every 20 years from 2000 to 2500 CE, under different CO2 emissions scenarios, using a general circulation model. We then apply a biome model to these modelled climate futures, to investigate shifts in climatic forcing on vegetation worldwide, the feasibility of the migration required to enact these modelled vegetation changes, and potential overlap with human land use based on modern-day anthromes. Under a business-as-usual scenario, up to 40% of terrestrial area is expected to be suited to a different biome by 2500. Cold-adapted biomes, particularly boreal forest and dry tundra, are predicted to experience the greatest losses of suitable area. Without mitigation, these changes could have severe consequences both for global biodiversity and the provision of ecosystem services

The Anthelmintic Activity of Praziquantel Analogs Correlates with Structure-Activity Relationships at TRPMPZQ Orthologs.

The anthelmintic drug praziquantel remains a key clinical therapy for treating various diseases caused by parasitic flatworms. The parasite target of praziquantel has remained undefined despite longstanding usage in the clinic, although a candidate ion channel target, named TRPMPZQ, has recently been identified. Intriguingly, certain praziquantel derivatives show different activities against different parasites: for example, some praziquantel analogs are considerably more active against cestodes than against schistosomes. Here we interrogate whether the different activities of praziquantel analogs against different parasites are also reflected by unique structure-activity relationships at the TRPMPZQ channels found in these different organisms. To do this, several praziquantel analogs were synthesized and functionally profiled against schistosome and cestode TRPMPZQ channels. Data demonstrate that structure-activity relationships are closely mirrored between parasites and their TRPMPZQ orthologs, providing further support for TRPMPZQ as the therapeutically relevant target of praziquantel

Improved understanding of spatio-temporal controls on regional scale groundwater flooding using hydrograph analysis and impulse response functions

Controls on the spatiotemporal extent of groundwater flooding are poorly understood, despite the long duration of groundwater flood events and distinct social and economic impacts. We developed a novel approach using statistical analysis of groundwater level hydrographs and impulse response functions (IRFs) and applied it to the 2013/14 Chalk groundwater flooding in the English Lowlands. We proposed a standardised index of groundwater flooding which we calculated for monthly groundwater levels for 26 boreholes in the Chalk. We grouped these standardised series using k-means cluster analysis and cross-correlated the cluster centroids with the Standardised Precipitation Index (SPI) accumulated over time intervals between 1 and 60 months. This analysis reveals two spatially coherent groups of standardised hydrographs which responded to precipitation over different timescales. We estimated IRF models of the groundwater level response to effective precipitation for three boreholes in each group. The IRF models corroborate the SPI analysis showing different response functions between the groups. We applied identical effective precipitation inputs to each of the IRF models and observed differences between the hydrographs from each group. It is suggested this is due to the hydrogeological properties of the Chalk and of overlying relatively low permeability superficial deposits (recent unconsolidated sediments overlying the bedrock, such as clays and tills), which are extensive over one of the groups. The overarching controls on groundwater flood response are concluded to be a complex combination of antecedent conditions, rainfall and catchment hydrogeological properties. These controls should be taken into consideration when anticipating and managing future groundwater flood events. The approach presented is generic and parsimonious and can be easily applied where sufficient groundwater level and rainfall data are available

Staff experiences of Providing Maternity Services in Rural Southern Tanzania -- A Focus on Equipment, Drug and Supply Issues.

The poor maintenance of equipment and inadequate supplies of drugs and other items contribute to the low quality of maternity services often found in rural settings in low- and middle-income countries, and raise the risk of adverse maternal outcomes through delaying care provision. We aim to describe staff experiences of providing maternal care in rural health facilities in Southern Tanzania, focusing on issues related to equipment, drugs and supplies. Focus group discussions and in-depth interviews were conducted with different staff cadres from all facility levels in order to explore experiences and views of providing maternity care in the context of poorly maintained equipment, and insufficient drugs and other supplies. A facility survey quantified the availability of relevant items. The facility survey, which found many missing or broken items and frequent stock outs, corroborated staff reports of providing care in the context of missing or broken care items. Staff reported increased workloads, reduced morale, difficulties in providing optimal maternity care, and carrying out procedures that carried potential health risks to themselves as a result. Inadequately stocked and equipped facilities compromise the health system's ability to reduce maternal and neonatal mortality and morbidity by affecting staff personally and professionally, which hinders the provision of timely and appropriate interventions. Improving stock control and maintaining equipment could benefit mothers and babies, not only through removing restrictions to the availability of care, but also through improving staff working conditions

Climate change, climatic variation and extreme biological responses

Extreme climatic events could be major drivers of biodiversity change, but it is unclear whether extreme biological changes are (i) individualistic (species- or group-specific), (ii) commonly associated with unusual climatic events and/or (iii) important determinants of long-term population trends. Using population time series for 238 widespread species (207 Lepidoptera and 31 birds) in England since 1968, we found that population 'crashes' (outliers in terms of species' year-to-year population changes) were 46% more frequent than population 'explosions'. (i) Every year, at least three species experienced extreme changes in population size, and in 41 of the 44 years considered, some species experienced population crashes while others simultaneously experienced population explosions. This suggests that, even within the same broad taxonomic groups, species are exhibiting individualistic dynamics, most probably driven by their responses to different, short-term events associated with climatic variability. (ii) Six out of 44 years showed a significant excess of species experiencing extreme population changes (5 years for Lepidoptera, 1 for birds). These 'consensus years' were associated with climatically extreme years, consistent with a link between extreme population responses and climatic variability, although not all climatically extreme years generated excess numbers of extreme population responses. (iii) Links between extreme population changes and long-term population trends were absent in Lepidoptera and modest (but significant) in birds. We conclude that extreme biological responses are individualistic, in the sense that the extreme population changes of most species are taking place in different years, and that long-term trends of widespread species have not, to date, been dominated by these extreme changes.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'

PTF11eon/SN2011dh: Discovery of a Type IIb Supernova From a Compact Progenitor in the Nearby Galaxy M51

On May 31, 2011 UT a supernova (SN) exploded in the nearby galaxy M51 (the Whirlpool Galaxy). We discovered this event using small telescopes equipped with CCD cameras, as well as by the Palomar Transient Factory (PTF) survey, and rapidly confirmed it to be a Type II supernova. Our early light curve and spectroscopy indicates that PTF11eon resulted from the explosion of a relatively compact progenitor star as evidenced by the rapid shock-breakout cooling seen in the light curve, the relatively low temperature in early-time spectra and the prompt appearance of low-ionization spectral features. The spectra of PTF11eon are dominated by H lines out to day 10 after explosion, but initial signs of He appear to be present. Assuming that He lines continue to develop in the near future, this SN is likely a member of the cIIb (compact IIb; Chevalier and Soderberg 2010) class, with progenitor radius larger than that of SN 2008ax and smaller than the eIIb (extended IIb) SN 1993J progenitor. Our data imply that the object identified in pre-explosion Hubble Space Telescope images at the SN location is possibly a companion to the progenitor or a blended source, and not the progenitor star itself, as its radius (~10^13 cm) would be highly inconsistent with constraints from our post-explosion photometric and spectroscopic data

F4‐02‐04: The Alzheimer’s Prevention Initiative (API) Program: Genetic Testing and Disclosure Strategies

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152610/1/alzjjalz201606595.pd