A Preliminary Investigation of High-speed Impact: the Penetration of Small Spheres into Thick Copper Targets

Small metal spheres of various densities were fired at high speed into thick targets of copper and lead. In general, it was found that all of the penetrations could be correlated quite well for engineering purposes by a function relating the depth of penetration to the impact momentum per unit volume

Development of a high-velocity free-flight launcher : the Ames light-gas gun

Recent interest in long-range missiles has stimulated a search for new experimental techniques which can reproduce in the laboratory the high temperatures and Mach numbers associated with the missiles' flight. One promising possibility lies in free-flight testing of laboratory models which are flown at the full velocity of the missile. In this type of test, temperatures are approximated and aerodynamic heating of the model is representative of that experienced by the missile in high-velocity flight. A prime requirement of the free-flight test technique is a device which had the capacity for launching models at the velocities desired. In response to thie need, a gun firing light models at velocities up to 15,000 feet per second has been developed at the Ames Aeronautical Laboratory. The design of this gun, the analysis of its performance, and the results of the initial firing trials are described in this paper. The firing trials showed that the measured velocities and pressures agreed well with the predicted values. Also, the erosion of the launch tube was very small for the eleven rounds fired. The performance of the gun suggests that it will prove to be a satisfactory launcher for high-velocity free-flight tests. However, it should be mentioned that only the gross performance has been evaluated so far, and, consequently, the operation of the gun must be investigated in further detail before its performance can be reliably predicted over its full operating range

Coronary artery calcification on routine CT has prognostic and treatment implications for all ages

Aims: Guidelines have recommended reporting coronary artery calcification (CAC) if present on chest CT imaging regardless of indication. This study assessed CAC prevalence, prognosis and the potential clinical impact of its reporting. Methods: We performed a single-centre retrospective analysis (January-December 2015) of 1400 chest CTs (200 consecutive within each age group: &lt;40, 40-49, 50-59, 60-69, 70-79, 80-89, ≥90). CTs were re-reviewed for CAC presence and severity and excluded if prior coronary intervention. Comorbidities, statin prescription and clinical outcomes (myocardial infarction [MI], stroke, all-cause mortality) were recorded. The impact of reporting CAC was assessed against pre-existing statin prescriptions. Results: 1343 patients were included (mean age 63±20 years, 56% female). Inter- and intra-observer variability for CAC presence at re-review was almost perfect (κ 0.89, p &lt; 0.001; κ 0.90, p &lt; 0.001) and for CAC grading was substantial and almost perfect (κ 0.68, p &lt; 0.001; κ 0.91, p &lt; 0.001). CAC was observed in 729/1343 (54%), more frequently in males (p &lt; 0.001) and rising age (p &lt; 0.001). A high proportion of patients with CAC in all age groups had no prior statin prescription (range: 42% [80-89] to 100% [&lt;40]). The ‘number needed to report’ CAC presence to potentially impact management across all ages was 2. 689 (51%) patients died (median follow-up 74-months). CAC presence was associated with risk of MI, stroke and all-cause mortality (p &lt; 0.001). After adjusting for confounders, severe calcification predicted risk of all-cause mortality (HR 1.8 [1.2-2.5], p = 0.002). Conclusion: Grading of CAC was reproducible, and although prevalence rose with age, prognostic and treatment implications were maintained in all ages.</p

Coronary artery calcification on routine CT has prognostic and treatment implications for all ages

Aims: Guidelines have recommended reporting coronary artery calcification (CAC) if present on chest CT imaging regardless of indication. This study assessed CAC prevalence, prognosis and the potential clinical impact of its reporting. Methods: We performed a single-centre retrospective analysis (January-December 2015) of 1400 chest CTs (200 consecutive within each age group: &lt;40, 40-49, 50-59, 60-69, 70-79, 80-89, ≥90). CTs were re-reviewed for CAC presence and severity and excluded if prior coronary intervention. Comorbidities, statin prescription and clinical outcomes (myocardial infarction [MI], stroke, all-cause mortality) were recorded. The impact of reporting CAC was assessed against pre-existing statin prescriptions. Results: 1343 patients were included (mean age 63±20 years, 56% female). Inter- and intra-observer variability for CAC presence at re-review was almost perfect (κ 0.89, p &lt; 0.001; κ 0.90, p &lt; 0.001) and for CAC grading was substantial and almost perfect (κ 0.68, p &lt; 0.001; κ 0.91, p &lt; 0.001). CAC was observed in 729/1343 (54%), more frequently in males (p &lt; 0.001) and rising age (p &lt; 0.001). A high proportion of patients with CAC in all age groups had no prior statin prescription (range: 42% [80-89] to 100% [&lt;40]). The ‘number needed to report’ CAC presence to potentially impact management across all ages was 2. 689 (51%) patients died (median follow-up 74-months). CAC presence was associated with risk of MI, stroke and all-cause mortality (p &lt; 0.001). After adjusting for confounders, severe calcification predicted risk of all-cause mortality (HR 1.8 [1.2-2.5], p = 0.002). Conclusion: Grading of CAC was reproducible, and although prevalence rose with age, prognostic and treatment implications were maintained in all ages.</p

Scaling solutions from interacting fluids

We examine the dynamical implications of an interaction between some of the fluid components of the universe. We consider the combination of three matter components, one of which is a perfect fluid and the other two are interacting. The interaction term generalizes the cases found in scalar field cosmologies with an exponential potential. We find that attracting scaling solutions are obtained in several regions of parameter space, that oscillating behaviour is possible, and that new curvature scaling solutions exist. We also discuss the inflationary behaviour of the solutions and present some of the constraints on the strength of the coupling, namely those arising from nucleosynthesis.Comment: RevTeX, 21 pages, 8 figure

A systematic screen for genes expressed in definitive endoderm by Serial Analysis of Gene Expression (SAGE)

BACKGROUND: The embryonic definitive endoderm (DE) gives rise to organs of the gastrointestinal and respiratory tract including the liver, pancreas and epithelia of the lung and colon. Understanding how DE progenitor cells generate these tissues is critical to understanding the cause of visceral organ disorders and cancers, and will ultimately lead to novel therapies including tissue and organ regeneration. However, investigation into the molecular mechanisms of DE differentiation has been hindered by the lack of early DE-specific markers. RESULTS: We describe the identification of novel as well as known genes that are expressed in DE using Serial Analysis of Gene Expression (SAGE). We generated and analyzed three longSAGE libraries from early DE of murine embryos: early whole definitive endoderm (0–6 somite stage), foregut (8–12 somite stage), and hindgut (8–12 somite stage). A list of candidate genes enriched for expression in endoderm was compiled through comparisons within these three endoderm libraries and against 133 mouse longSAGE libraries generated by the Mouse Atlas of Gene Expression Project encompassing multiple embryonic tissues and stages. Using whole mount in situ hybridization, we confirmed that 22/32 (69%) genes showed previously uncharacterized expression in the DE. Importantly, two genes identified, Pyy and 5730521E12Rik, showed exclusive DE expression at early stages of endoderm patterning. CONCLUSION: The high efficiency of this endoderm screen indicates that our approach can be successfully used to analyze and validate the vast amount of data obtained by the Mouse Atlas of Gene Expression Project. Importantly, these novel early endoderm-expressing genes will be valuable for further investigation into the molecular mechanisms that regulate endoderm development

Factors influencing consumer wine choice: The case of wine tourism

This research was undertaken to examine the relationship between the wine tourism activities of consumers and their subsequent wine choices. Exploratory research was undertaken giving specific attention to wine tourism, first, as a factor of influence on decision-making, second, on levels of consumer involvement and third on long-term consumer loyalty. A convenience sample of 12 wine consumers in Dublin participated in the study. Semi-structured in-depth interviews were used to gather the qualitative data used. The findings clearly establish links made by consumers between their wine tourism experiences and their subsequent wine purchase preferences. The findings highlight the importance of facilitating the co-creation of memorable wine tourism experiences as a determinant of improved consumer involvement as well as the development of long-term consumer loyalty. Implications for industry practitioners suggest a continued focus on the provision of unique wine tourism experiences; while the findings support the theoretical links between consumers own past experiences and their use as a valuable information source when making purchase decisions

Identification of Equid herpesvirus 2 in tissue-engineered equine tendon

Background: Incidental findings of virus-like particles were identified following electron microscopy of tissue-engineered tendon constructs (TETC) derived from equine tenocytes. We set out to determine the nature of these particles, as there are few studies which identify virus in tendons per se, and their presence could have implications for tissue-engineering using allogenic grafts. Methods: Virus particles were identified in electron microscopy of TETCs. Virion morphology was used to initially hypothesise the virus identity.  Next generation sequencing was implemented to identify the virus. A pan herpesvirus PCR was used to validate the RNASeq findings using an independent platform. Histological analysis and biochemical analysis was undertaken on the TETCs. Results: Morphological features suggested the virus to be either a retrovirus or herpesvirus. Subsequent next generation sequencing mapped reads to Equid herpesvirus 2 (EHV2). Histological examination and biochemical testing for collagen content revealed no significant differences between virally affected TETCs and non-affected TETCs. An independent set of equine superficial digital flexor tendon tissue (n=10) examined using designed primers for specific EHV2 contigs identified at sequencing were negative. These data suggest that EHV is resident in some equine tendon. Conclusions: EHV2 was demonstrated in equine tenocytes for the first time; likely from in vivo infection. The presence of EHV2 could have implications to both tissue-engineering and tendinopathy

A data mining approach in home healthcare: outcomes and service use

BACKGROUND: The purpose of this research is to understand the performance of home healthcare practice in the US. The relationships between home healthcare patient factors and agency characteristics are not well understood. In particular, discharge destination and length of stay have not been studied using a data mining approach which may provide insights not obtained through traditional statistical analyses. METHODS: The data were obtained from the 2000 National Home and Hospice Care Survey data for three specific conditions (chronic obstructive pulmonary disease, heart failure and hip replacement), representing nearly 580 patients from across the US. The data mining approach used was CART (Classification and Regression Trees). Our aim was twofold: 1) determining the drivers of home healthcare service outcomes (discharge destination and length of stay) and 2) examining the applicability of induction through data mining to home healthcare data. RESULTS: Patient age (85 and older) was a driving force in discharge destination and length of stay for all three conditions. There were also impacts from the type of agency, type of payment, and ethnicity. CONCLUSION: Patients over 85 years of age experience differential outcomes depending on the condition. There are also differential effects related to agency type by condition although length of stay was generally lower for hospital-based agencies. The CART procedure was sufficiently accurate in correctly classifying patients in all three conditions which suggests continuing utility in home health care