Walking the Walk/Talking the Talk: Mission Planning with Speech-Interactive Agents

The application of simulation technology to mission planning and rehearsal has enabled realistic overhead 2-D and immersive 3-D "fly-through" capabilities that can help better prepare tactical teams for conducting missions in unfamiliar locales. For aircrews, detailed terrain data can offer a preview of the relevant landmarks and hazards, and threat models can provide a comprehensive glimpse of potential hot zones and safety corridors. A further extension of the utility of such planning and rehearsal techniques would allow users to perform the radio communications planned for a mission; that is, the air-ground coordination that is critical to the success of missions such as close air support (CAS). Such practice opportunities, while valuable, are limited by the inescapable scarcity of complete mission teams to gather in space and time during planning and rehearsal cycles. Moreoever, using simulated comms with synthetic entities, despite the substantial training and cost benefits, remains an elusive objective. In this paper we report on a solution to this gap that incorporates "synthetic teammates" - intelligent software agents that can role-play entities in a mission scenario and that can communicate in spoken language with users. We employ a fielded mission planning and rehearsal tool so that our focus remains on the experimental objectives of the research rather than on developing a testbed from scratch. Use of this planning tool also helps to validate the approach in an operational system. The result is a demonstration of a mission rehearsal tool that allows aircrew users to not only fly the mission but also practice the verbal communications with air control agencies and tactical controllers on the ground. This work will be presented in a CAS mission planning example but has broad applicability across weapons systems, missions and tactical force compositions

Sulphur-isotope compositions of pig tissues from a controlled feeding study

Sulphur-isotope determinations are becoming increasingly useful for palaeodietary reconstruction, but knowledge of isotopic discrimination between diet and various tissues remains inadequate. In this study, we explore the sensitivity of δ34Stissue values to changes in δ34Sdiet values, sulphur isotopic discrimination between diet and consumer, and the potential impact of terrestrial vs. marine protein consumption on these discrimination offsets. We present new δ34S values of bone collagen, muscle, liver, hair, milk and faeces from ten mature sows, ten piglets and fifteen adolescent pigs from a controlled feeding study. The δ34Stissue values were found to co-vary with the δ34Sdiet values, the δ34Stissue – δ34Sdiet isotopic offsets (Δ34Stissue-diet) are small but consistent, and dietary protein source does not systematically alter the Δ34Stissue-diet isotopic discrimination. The outcomes of this study are of particular relevance to questions that are difficult to resolve using carbon and nitrogen stable isotopes alone, and will also be useful in regions where terrestrial, freshwater, and marine resources could have all potentially contributed to human diet

The association between hysterectomy and ovarian cancer risk: A population-based record-linkage study

Background: Recent studies have called into question the long-held belief that hysterectomy without oophorectomy protects against ovarian cancer. This population-based longitudinal record-linkage study aimed to explore this relationship, overall and by age at hysterectomy, time period, surgery type, and indication for hysterectomy. Methods: We followed the female adult Western Australian population (837 942 women) across a 27-year period using linked electoral, hospital, births, deaths, and cancer records. Surgery dates were determined from hospital records, and ovarian cancer diagnoses (n¼1640) were ascertained from cancer registry records.We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between hysterectomy and ovarian cancer incidence. Results: Hysterectomy without oophorectomy (n¼78 594) was not associated with risk of invasive ovarian cancer overall (HR ¼ 0.98, 95% CI ¼ 0.85 to 1.11) or with the most common serous subtype (HR ¼ 1.05, 95% CI ¼ 0.89 to 1.23). Estimates did not vary statistically significantly by age at procedure, time period, or surgical approach. However, among women with endometriosis (5.8%) or with fibroids (5.7%), hysterectomy was associated with substantially decreased ovarian cancer risk overall (HR ¼ 0.17, 95% CI ¼ 0.12 to 0.24, and HR ¼ 0.27, 95% CI ¼ 0.20 to 0.36, respectively) and across all subtypes. Conclusions: Our results suggest that for most women, having a hysterectomy with ovarian conservation is not likely to substantially alter their risk of developing ovarian cancer. However, our results, if confirmed, suggest that ovarian cancer risk reduction could be considered as a possible benefit of hysterectomy when making decisions about surgical management of endometriosis or fibroids

A Neural Model for Insect Steering Applied to Olfaction and Path Integration

Many animal behaviors require orientation and steering with respect to the environment. For insects, a key brain area involved in spatial orientation and navigation is the central complex. Activity in this neural circuit has been shown to track the insect’s current heading relative to its environment and has also been proposed to be the substrate of path inte-gration. However, it remains unclear how the output of the central complex is integrated into motor commands. Central complex output neurons project to the lateral accessory lobes (LAL), from which descending neurons project to thoracic motor centers. Here, we present a computational model of a simple neural network that has been described anatomically and physiologically in the LALs of male silkworm moths, in the context of odor-mediated steering. We present and analyze two versions of this network, one rate based and one based on spiking neurons. The mod-eled network consists of an inhibitory local interneuron and a bistable descending neuron (flip-flop) that both receive input in the LAL. The flip-flop neuron projects onto neck motor neurons to induce steering. We show that this simple computational model not only replicates the basic parameters of male silkworm moth behavior in a simulated odor plume but can also take input from a computational model of path integration in the central complex and use it to steer back to a point of origin. Fur-thermore, we find that increasing the level of detail within the model im-proves the realism of the model’s behavior, leading to the emergence of looping behavior as an orientation strategy. Our results suggest that descending neurons originating in the LALs, such as flip-flop neurons, are sufficient to mediate multiple steering behaviors. This study is therefore a first step to close the gap between orientation circuits in the central complex and downstream motor centers

Hydrogen partitioning as a function of time-on-stream for an unpromoted iron-based Fischer-Tropsch synthesis catalyst applied to CO hydrogenation

Sasol Ltd., the EPSRC (award reference EP/P505534/1), and the University of Glasgow are thanked for the provision of a postgraduate studentship (ALD). The STFC Rutherford Appleton Laboratory is thanked for access to neutron beam facilities. The Royal Society is thanked for the provision of an Industry Fellowship (PBW).Inelastic neutron scattering (INS) is employed to examine the evolution of a promoter-free iron-based Fischer-Tropsch synthesis catalyst (∼10 g catalyst charge) that is exposed to ambient pressure CO hydrogenation at 623 K for up to 10 days time-on-stream (T-o-S). The longer reaction time is selected to better understand how the formation of a previously described hydrocarbonaceous overlayer corresponds to the catalyst conditioning process. Although the onset of pseudo steady-state reactor performance is observed at approximately 9 h T-o-S, INS establishes that the intensity of the C-H stretching mode of the sp3-hybridized component of the hydrocarbonaceous overlayer saturates at about 24 h T-o-S, while the corresponding intensity of the C-H stretching mode of the sp2-hybridized component requires 100-200 h T-o-S to achieve saturation. This novel series of measurements reveal different aspects of the complex catalyst evolutionary process to be indirectly connected with catalytic turnover.Publisher PDFPeer reviewe

Age effects and the influence of varying proportions of terrestrial and marine dietary protein on the stable nitrogen-isotope compositions of pig bone collagen and soft tissues from a controlled feeding experiment

In this study, femoral collagen, rib collagen, femoral muscle, loin muscle and liver samples from sows, piglets and pigs raised in a controlled feeding study are analysed for their nitrogen-isotope compositions. The objectives of this research are to investigate the relationship between tissue and dietary δ15N values across age categories under controlled feeding and housing conditions, and to assess tissue 15N-enrichment relative to diet when pigs of different ages are consuming terrestrial, marine, or mixed terrestrial-marine dietary protein. There is a strong linear relationship between all tissue δ15N values and the amount of marine protein consumed, but the δ15N values do not become consistently elevated for all individuals consuming the same diet until at least 25% of the dietary protein source is marine-derived. Adolescent pigs also had consistently lower δ15N values than either piglets or sows consuming the same diet for collagen and muscle, which is most likely caused by the differences in growth rate among the age categories. Further, for some tissues and animals, a linear relationship between the amount of marine protein consumed and the Δ15NTissue – Whole Diet offset was also observed. We suggest that this variability results from both age-associated growth rates and differential incorporation of amino acids from terrestrial and marine dietary protein into rapidly growing tissue

Do rating agencies exhibit herding behaviour? Evidence from sovereign ratings

We assess the presence of herding by considering the lead-lag relationship of sovereign ratings assigned by the three main rating agencies at the individual country level. Given that different rating agencies may have different levels of expertise (reputation) for different countries it is not obvious that the lead-lag relationship is homogeneous across countries. We therefore conduct poolability tests within this context to assess this assumption and find evidence of heterogeneity. This leads us to conduct country-by-country time-series tests to assess the lead-lag relationship among agencies. To our knowledge we are the first to do this and thereby extend the literature on herding among rating agencies' sovereign assignments. We also consider changes in the lead-lag relationship through time by splitting the sample into pre-crisis and crisis periods to assess the extent to which any herding is intentional and our results indicate some degree of heterogeneity through time. To the extent that there is herding we find that it is generally towards Standard and Poor's ratings confirming our expectations given that this agency is regarded as possessing the greatest reputational capital. However, our results do not support the expectation that Fitch is a follower for more (a leader for less) countries than Moody's

The application of inelastic neutron scattering to investigate iron-based Fischer-Tropsch to olefins catalysis

Sasol Ltd., the University of Glasgow and EPSRC [award reference EP/P505534/1.] are thanked for the provision of postgraduate studentship (ALD). The STFC Rutherford Appleton Laboratory is thanked for access to neutron beam facilities [RB 1520269/1610413]. Diamond Light Source is thanked for time on B18 beamline through the Catalysis Hub BAG application (SP15151 and rapid access beamtime SP18431). The Royal Society is thanked for the provision of an Industry Fellowship (PBW).The technique of inelastic neutron scattering (INS) is used to investigate how hydrogen is partitioned within a series of Na and S promoted iron-based Fischer-Tropsch-to-olefin catalysts. Two reaction test regimes are examined. First, reaction testing at elevated temperature and pressure demonstrate how Na/S additions enhance short chain olefin selectivity and reduce methane formation under industrially relevant reaction conditions. For a fixed level of Na incorporation (2000 ppm), sulfur concentrations of ≤ 100 ppm result in only a modest improvement in olefin selectivity. However, for sulfur values of ≥ 100 ppm there is a noticeable and systematic increase in C2-C4 olefin selectivity; rising from ∼30.0 % to 35.2% at 250 ppm. Second, using ambient pressure CO hydrogenation as a test reaction in INS and micro-reactor configurations, catalyst samples are further analysed by TPR, TPO, XRD and S K-edge XANES. INS shows the formation of a hydrocarbonaceous overlayer to be significantly attenuated by the presence of the promoters, with increasing S levels significantly reducing the intensity of the sp2 and sp3 hybridised ν(C-H) modes of the overlayer, albeit to differing degrees. A probable role for how this combination of promoters is perturbing the form of the hydrocarbonaceous overlayer to subsequently moderate the product distribution is considered.Publisher PDFPeer reviewe