Balancing the trade : Roman cargo shipments to India

There has been a continuing debate about the extent to which the Roman Empire suffered an economic imbalance in its trade with India (and more broadly the East), that is to say whether in volume or value the Roman Empire imported more than it exported. This imbalance is often thought to be manifested in the export of Roman gold and silver to India and the connected notion that other goods from the Roman Empire were seen as merely items of ballast. It is the intention of this article to place this debate in a practical context by demonstrating not only the physical need for mixed cargoes on ships sailing to India, but also the negligible amount of space taken up by the gold and silver. It is argued that in terms of volume (if not value) goods in-kind were far more significant

The Exchange of Goods from Italy to India during the Early Roman Empire – The Range of Travelling Times

This paper examines the evidence for the time taken for a circuitous flow of goods between Italy and India to occur. It is argued that the distinct nature of the Mediterranean and Indian Ocean trading spheres meant that it was often not possible for this circuit to be completed within one year. In particular, a comparison of papyrological, epigraphic and literary sources indicates that a variety of natural and manmade factors greatly impacted on these schedules. Consequently the goods which were traded between these two economic zones fluctuated in volume, nature and the prices for which they were sold

The Decline of Ptolemaic Elephant Hunting: An Analysis of the Contributory Factors

After the death of Alexander the Great in 323, his successors (diadochi) engaged in a series of internecine struggles to take control of the territory he had conquered. One of the most capable of these, Ptolemy, the son of Lagus (later to become Ptolemy I Soter), took control of Egypt, initially as satrap (323–306) and subsequently as king (306–283/282). Over several decades Ptolemy was able to seize Coele-Syria and parts of Asia Minor, and achieved leadership of the League of Islanders in the Aegean. The battles between the successors were fought with sizable infantry and cavalry forces. However, one of the most notable and highly valued components of these military forces were battle elephants.</jats:p

Development of a low profile laser Doppler probe for monitoring perfusion at the patient – mattress interface

The clinical importance of pressure ulcers is reviewed confirming the need for continuous monitoring of skin blood perfusion at the patient – mattress interface. The design of a low profile (H≈1mm) laser Doppler probe is then described together with the experimental setup used for evaluation. The results show that the performance of the new sensor does not vary significantly from that of currently available probes over a wide range of operating parameters. The authors conclude that the sensor design provides a low cost perfusion monitoring solution with potential to significantly reduce the risk of bed sores in hospital patients

Public Interest in Medical Research Participation: Differences by Volunteer Status and Study Type

Purpose We assessed national levels of public interest in medical research participation (MRP) and factors associated with interest as a healthy volunteer; as a diagnosed volunteer; and in seven study types. Method Cross‐sectional, Web‐based survey of the US population in June 2012. Descriptive statistics estimated interest in MRP and multivariable logistic regression determined associations between respondent‐level predictors and interest in MRP. Results Of 2,668 respondents (response rate = 61%), 41% were interested in MRP as healthy volunteers and 60% as diagnosed volunteers. Respondents with some college (OR = 1.54, 1.09–2.19) or higher education (OR = 1.86, 1.29–2.70) had higher adjusted odds of interest as healthy volunteers. Non‐Hispanic black race (OR = 0.56, 0.37–0.86) and education below high school (OR = 0.57, 0.35–0.92) were associated with lower adjusted odds of interest as diagnosed volunteers. Non‐Hispanic black race was associated with lower odds of interest in medication trials as diagnosed volunteers (OR = 0.61, 0.40–0.93). Conclusions We found high levels of interest in MRP that contrast with low levels of prior research participation. Interest is higher in medical research involving noninvasive designs. Comparatively lower levels of interest in MRP among non‐Hispanic blacks and those with less education raise concerns about disparities in future study enrollment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106963/1/cts12142.pd

Modeling cancer genomic data in yeast reveals selection against ATM function during tumorigenesis

The DNA damage response (DDR) comprises multiple functions that collectively preserve genomic integrity and suppress tumorigenesis. The Mre11 complex and ATM govern a major axis of the DDR and several lines of evidence implicate that axis in tumor suppression. Components of the Mre11 complex are mutated in approximately five percent of human cancers. Inherited mutations of complex members cause severe chromosome instability syndromes, such as Nijmegen Breakage Syndrome, which is associated with strong predisposition to malignancy. And in mice, Mre11 complex mutations are markedly more susceptible to oncogene- induced carcinogenesis. The complex is integral to all modes of DNA double strand break (DSB) repair and is required for the activation of ATM to effect DNA damage signaling. To understand which functions of the Mre11 complex are important for tumor suppression, we undertook mining of cancer genomic data from the clinical sequencing program at Memorial Sloan Kettering Cancer Center, which includes the Mre11 complex among the 468 genes assessed. Twenty five mutations in MRE11 and RAD50 were modeled in S. cerevisiae and in vitro. The mutations were chosen based on recurrence and conservation between human and yeast. We found that a significant fraction of tumor-borne RAD50 and MRE11 mutations exhibited separation of function phenotypes wherein Tel1/ATM activation was severely impaired while DNA repair functions were mildly or not affected. At the molecular level, the gene products of RAD50 mutations exhibited defects in ATP binding and hydrolysis. The data reflect the importance of Rad50 ATPase activity for Tel1/ATM activation and suggest that inactivation of ATM signaling confers an advantage to burgeoning tumor cells

Training safer orthopedic surgeons Construct validation of a virtual-reality simulator for hip fracture surgery

BACKGROUND AND PURPOSE: Virtual-reality (VR) simulation in orthopedic training is still in its infancy, and much of the work has been focused on arthroscopy. We evaluated the construct validity of a new VR trauma simulator for performing dynamic hip screw (DHS) fixation of a trochanteric femoral fracture. PATIENTS AND METHODS: 30 volunteers were divided into 3 groups according to the number of postgraduate (PG) years and the amount of clinical experience: novice (1–4 PG years; less than 10 DHS procedures); intermediate (5–12 PG years; 10–100 procedures); expert (> 12 PG years; > 100 procedures). Each participant performed a DHS procedure and objective performance metrics were recorded. These data were analyzed with each performance metric taken as the dependent variable in 3 regression models. RESULTS: There were statistically significant differences in performance between groups for (1) number of attempts at guide-wire insertion, (2) total fluoroscopy time, (3) tip-apex distance, (4) probability of screw cutout, and (5) overall simulator score. The intermediate group performed the procedure most quickly, with the lowest fluoroscopy time, the lowest tip-apex distance, the lowest probability of cutout, and the highest simulator score, which correlated with their frequency of exposure to running the trauma lists for hip fracture surgery. INTERPRETATION: This study demonstrates the construct validity of a haptic VR trauma simulator with surgeons undertaking the procedure most frequently performing best on the simulator. VR simulation may be a means of addressing restrictions on working hours and allows trainees to practice technical tasks without putting patients at risk. The VR DHS simulator evaluated in this study may provide valid assessment of technical skill

Recoverable resources calculation using non-linear methods: a comparative study

The prediction of recoverable resources at an operating manganese mine is currently undertaken using univariate ordinary kriging of the target variable manganese, and 5 deleterious variables. Input data densities at the time of this calculation are considerably lower than at the time of final selection (grade control), and the potential for unnacceptable conditional bias to be introduced through the use of linear geostatistical methods when determining grade estimates over a small support has led to assessment of the potential benefit of employing the local change of support methods Localised Uniform Conditioning (LUC) and Conditional Simulation (CS). Allowances for the operating conditions, including time frames for estimation / simulation, and likely software limitations are accounted for by also requiring decorrelation to be used in instances where the data are considered in a multivariate sense. A novel method for decorrelation of geostatistical datasets, Independent Components Analysis (ICA), is compared against the more common method of Minimum-Maximum Autocorrelation Factorisation (MAF). ICA performs comparably against MAF in terms of its ability to diagonalise the variance-covariance matrix of the test dataset over multiple lags, for a variety of input data densities and treatments (log-ratio transformed and raw oxide data). Based on these results, ICA decorrelated data were incorporated into a comparative study of LUC and CS against block ordinary kriging (BOK), using an input dataset of reduced density, treated variously as raw univariate oxide data, decorrelated oxide data, and log-ratio transformed decorrelated data. The use of the log-ratio transform, designed to account for the 100% sum constraint inherent to the input data, proved impractical for LUC due to difficulties associated with the discrete Gaussian model change of support method employed by this technique. Log-ratio data transformation was restricted to use with CS where back transformation to raw oxide space could take place on a pseudo-equivalent support to the input data, prior to change of support. While use of the log-ratio transformation for CS guaranteed adherence to the sum constraint for results (the only method to do so) it resulted in distortion to both the spatial and grade distribution of results. Decorrelation by ICA also posed difficulties, with biases introduced to final back transformed results as a result of the decorrelation algorithm in both log-ratio transformed and oxide data, which in some instances caused impossible negative values to be returned for some variables in the final results. In a comparison of net profit calculations for each method, the distortions introduced from both log-ratio transformation, and decorrelation become evident in either overly optimistic or conservative profit distributions for methods in which they were used. Of the results presented, only BOK, CS and LUC of non-decorrelated oxide data appear to show results similar to those which would be used at the operation during final selection (based on ordinary kriging of a complete dataset). Based on the comparison of spatial grade distributions and both net profit spatial distribution and summary, the decision to employ a non-linear method of recoverable resource calculation at the operation under question would be questionable in terms of its reward for effort, given that the current method of BOK appears to produce equivalent results

A Resource Manual for Mainstreaming Students with Behavioral Disabilities in the Middle School

The purpose of this project was to develop a resource manual to facilitate the use of effective components for mainstreamed or included Behavior Disabled (BD) students in the regular classroom. The manual will be used by Wapato Middle School, Wapato, Washington, to enhance the current mainstream/ inclusion program. To accomplish this purpose, current research and literature related to BD student characteristics, legal issues, instructional strategies and policies were reviewed

How different data sources and definitions of neighbourhood influence the association between food outlet availability and body mass index: a cross-sectional study.

Inconsistencies in methodologies continue to inhibit understanding of the impact of the environment on body mass index (BMI). To estimate the effect of these differences, we assessed the impact of using different definitions of neighbourhood and data sets on associations between food outlet availability within the environment and BMI. Previous research has not extended this to show any differences in the strength of associations between food outlet availability and BMI across both different definitions of neighbourhood and data sets. Descriptive statistics showed differences in the number of food outlets, particularly other food retail outlets between different data sets and definitions of neighbourhood. Despite these differences, our key finding was that across both different definitions of neighbourhood and data sets, there was very little difference in size of associations between food outlets and BMI. Researchers should consider and transparently report the impact of methodological choices such as the definition of neighbourhood and acknowledge any differences in associations between the food environment and BMI