An online learning approach to in-vivo tracking using synergistic features

In this paper we present an online algorithm for robustly tracking surgical tools in dynamic environments that can assist a surgeon during in-vivo robotic surgery procedures. The next generation of in-vivo robotic surgical devices includes integrated imaging and effector platforms that need to be controlled through real-time visual feedback. Our tracking algorithm learns the appearance of the tool online to account for appearance and perspective changes. In addition, the tracker uses multiple features working together to model the object and discover new areas of the tool as it moves quickly, exits and re-enters the scene, or becomes occluded and requires recovery. The algorithm can persist through changes in lighting and pose by using a memory database, which is built online, using a series of features working together to exploit different aspects of the object being tracked. We present results using real in-vivo imaging data from a human partial nephrectomy

Selfish and Altruistic Bacterial Populations Maximize Fitness Under Stress by Local Segregation

Landscapes in ecology have a profound influence on the adaption and evolution of competing populations for resources. We are interested in how altruistic populations survive in the presence of selfish individuals in a non-stirred, closed and complex nutrient landscape. Well-stirred (landscape-free) but closed environments have a depressing future when selfish individuals arise in a population, a fate known as the tragedy of the Commons. Over-exploitation of a well-stirred communal habitat by selfish individuals which do not follow rules of communal self-regulation ends up in the elimination (extinction) of both the original altruistic inhabitants and the selfish population. In the context of bacterial population, the Commons tragedy that occurs is the consumption of limited resources by the individuals, resulting in metabolic stressing of the bacteria and growth advantages to be gained by defection from a ``social contract" of altruistic cooperation. There is no avoidance of this tragedy and the collapse of an original altruistic wild-type population by an emergent selfish population in a well-stirred but closed environment is inevitable. However, there is a fundamental difference between resource exploitation in a well-stirred homogenous commons and in a heterogenous landscape of nutrients which is not stirred. We show here using a non-stirred nanofabricated habitat landscape that altruists and selfish bacteria can in fact coexist, that they can maintain phenotype diversity and avoid the tragedy of the Commons. This emergent spatial segregation of competing populations under stress greatly changes, we believe, our perception of the true sophistication of bacterial response to stress and competition, and has broad implications for the adaptive strategies of higher organisms under stress in complex environments

The potential for isothermal microcalorimetry to detect venous catheter infection isolates and establish antibiograms

OBJECTIVES: Because bloodstream infection and venous catheter (or cannula) bloodstream infection are associated with high morbidity and cost, early identification and treatment are important. Isothermal microcalorimetry can detect microbial growth using thermal power (heat flow), essentially in real time. The aim of this study was to examine the potential of this technique in clinical practice. METHODS: Thermal power of wild-type bacteria (Escherichia coli, Staphylococcus epidermidis, Klebsiella pneumoniae, and Enterococcus faecium) isolated from blood cultures of adult inpatients receiving parenteral nutrition in routine clinical practice was measured at 37°C every 10s using a Thermometric 2277 instrument. Temporal patterns of heat flow were used to detect the presence of bacteria, differentiate between them, and test their antibiotic sensitivity. Within and between batch reproducibility (% coefficient of variation [%CV]) was also established. RESULTS: Isothermal microcalorimetry always correctly detected the absence or presence of wild-type bacteria. Thermograms differed distinctly between species. Key thermographic features, such as peak heights, timing of peak heights, and interval between peak heights, were highly reproducible within each species (within-batch %CV usually about ≤1%, although between-batch %CV was usually higher). The antibiotic sensitivities (tested only for S. epidermidis and K. pneumoniae) confirmed the results obtained from the hospital laboratory. CONCLUSIONS: Isothermal microcalorimetry is a promising and highly reproducible real-time measurement technique with potential application to the investigation, species identification, and targeted antibiotic treatment of bloodstream infection and venous catheter (or cannula) bloodstream infection

Do GPs use electronic mental health resources? A qualitative study

BACKGROUNDThe Better Outcomes in Mental Health Care (BOMHC) initiative encourages general practitioners to use electronic mental health resources (EMHRs) during consultation with patients requiring psychological assistance. However, there is little data on GPs&rsquo; acceptance and use of EMHRs.METHODSemistructured interviews were conducted with 27 GPs to determine their attitude toward EMHRs, and their use during consultation with patients.RESULTSFew GPs reported frequently using EMHRs in consultation. Identified barriers to use included lack of familiarity with information technology, and insufficient knowledge of available resources. Identified advantages of electronic resources included high patient acceptance, time efficiency, and improved quality of information.DISCUSSIONGeneral practitioners recognise several advantages of utilising electronic resources for managing patients with mental illness. However, GPs are not sufficiently familiar with electronic resources to use them effectively. This could be overcome by education.<br /

Accuracy Assessment of the eBee Using RTK and PPK Corrections Methods as a Function of Distance to a GNSS Base Station

The use of unmanned aircraft systems to collect data for photogrammetry models has grown significantly in recent years. The accuracy of a photogrammetric model can depend on image georeferencing. The distance from a reference base station can affect the accuracy of the results. Positioning corrections data relies on precise timing measurements of satellite signals. The signals travel through the Earth\u27s atmosphere, which introduces errors due to ionospheric and tropospheric delays. The aim of this research was to examine the eBee X and its global GNSS accuracy by comparing the RTK and PPK methods at different base station distances in photogrammetry models. Three factors were compared: 1) RTK and PPK methods, 2) local GNSS receiver via caster and NTRIP service corrections sources, and 3) base station distances between 2.4 km and 42.0 km. The eBee X flights occurred in 2023, at three different flying sites in Southwest Arizona in the United States. The RMSEXYZ values from eight Check Points at each of three flying sites were measured with traditional GNSS survey methods. Through ANOVA testing, there were no statistical differences in RMSEXYZ accuracy between RTK and PPK methods as well as between using a local Reach RS2 GNSS receiver via caster and NTRIP service for the eBee X; however, there was a statistical difference in RMSEXYZ accuracy between base station distances of 2.4 km to 42.0 km, whereas, F(5, 33) = 11.99, p = 0.000. Specifically, base station distances of less than 16.2 km were significantly less than larger distances up to 42.0 km. These data suggest there was a significant difference in total accuracy based on the distance from the GNSS receiver base station providing corrections for the eBee X

A learning algorithm for visual pose estimation of continuum robots

Continuum robots offer significant advantages for surgical intervention due to their down-scalability, dexterity, and structural flexibility. While structural compliance offers a passive way to guard against trauma, it necessitates robust methods for online estimation of the robot configuration in order to enable precise position and manipulation control. In this paper, we address the pose estimation problem by applying a novel mapping of the robot configuration to a feature descriptor space using stereo vision. We generate a mapping of known features through a supervised learning algorithm that relates the feature descriptor to known ground truth. Features are represented in a reduced sub-space, which we call eigen-features. The descriptor provides some robustness to occlusions, which are inherent to surgical environments, and the methodology that we describe can be applied to multi-segment continuum robots for closed-loop control. Experimental validation on a single-segment continuum robot demonstrates the robustness and efficacy of the algorithm for configuration estimation. Results show that the errors are in the range of 1°

Using Unmanned Aircraft Systems to Investigate the Detectability of Burmese Pythons in South Florida

Burmese pythons are an invasive, non-native species of snake to southern Florida and attempts at eradicating the snakes had yielded mixed results. The current rate of detection had been reported as 0.05%. The purpose of this research project was to determine if a UAS equipped with a near-infrared (NIR) camera could be used to detect pythons at a higher rate when compared to a RGB camera. The approach involved collecting 55 images from RGB and NIR cameras, over carcass pythons at flying heights of 3, 6, 9, 12, and 15 meters. A likelihood ratio consisting of a true positive rate over false positive rate was calculated from 101 participant survey responses. Participants were able to detect pythons from an NIR camera with greater likelihood (M = 6.05, SD = 1.94) than a RGB camera (M = 4.74, SD = 1.32), t(10) = 1.77, p = .048. The data suggests that survey participants could correctly detect pythons in images containing the pythons at a 1.3x greater rate with the NIR sensor than with the RGB sensor. Also, a true positive rate (TPR) showed the observation rate of correctly detecting a python when one was present in the image. The NIR camera images had higher TPR rates compared to RGB images. The largest difference between camera types was observed at the 15 meters flying height over an outstretched python; there was a 35% increase in participant detection accuracy using the NIR camera compared to the RGB camera. These results suggest that a UAS equipped with an NIR camera flying between 3 and 15 meters in a nadir-oriented position of 90 degrees can be used to detect pythons. Using a UAS equipped with an NIR camera over levees searching for exposed pythons may help biologists responsible for managing these invasive species determine if a python is present

Evaluation of biogenic amines in the faeces of children with and without autism by LC-MS/MS

Previous researchers have postulated that gastrointestinal bacteria may contribute to the development and maintenance of Autism Spectrum Disorders (ASD). There is evidence based on quantitative evaluation of the gastrointestinal bacterial population in ASD that this is unlikely and an alternate mechanism will be examined where the bacteria may contribute to the development of ASD via their metabolic products and the role of biogenic amines (BAs) will be investigated. In humans, BAs influence a number of physiological processes via their actions as neurotransmitters, local hormones and gastric acid secretion. Various amines have been implicated in several medical conditions such as schizophrenia and colon cancer. To date, the relationship between BAs and autism has not been explored. This study has been designed to identify differences (and/or similarities) in the level of Bas in faecal samples of autistic children (without gastrointestinal dysfunction: n = 14; with gastrointestinal dysfunction; n = 21) and their neurotypical siblings (n = 35) by LC-MS/MS. Regardless of the diagnosis, severity of ASD and gastrointestinal dysfunction there were no significant differences found between the groups. The findings suggest that BAs in the gastrointestinal tract do not play a role in the pathophysiology of gastrointestinal dysfunction associated with ASD

Geographic and temporal validity of prediction models: different approaches were useful to examine model performance

AbstractObjectiveValidation of clinical prediction models traditionally refers to the assessment of model performance in new patients. We studied different approaches to geographic and temporal validation in the setting of multicenter data from two time periods.Study Design and SettingWe illustrated different analytic methods for validation using a sample of 14,857 patients hospitalized with heart failure at 90 hospitals in two distinct time periods. Bootstrap resampling was used to assess internal validity. Meta-analytic methods were used to assess geographic transportability. Each hospital was used once as a validation sample, with the remaining hospitals used for model derivation. Hospital-specific estimates of discrimination (c-statistic) and calibration (calibration intercepts and slopes) were pooled using random-effects meta-analysis methods. I2 statistics and prediction interval width quantified geographic transportability. Temporal transportability was assessed using patients from the earlier period for model derivation and patients from the later period for model validation.ResultsEstimates of reproducibility, pooled hospital-specific performance, and temporal transportability were on average very similar, with c-statistics of 0.75. Between-hospital variation was moderate according to I2 statistics and prediction intervals for c-statistics.ConclusionThis study illustrates how performance of prediction models can be assessed in settings with multicenter data at different time periods

Adverse cardiovascular events during treatment with pioglitazone and rosiglitazone: population based cohort study

Objective To compare the risk of acute myocardial infarction, heart failure, and death in patients with type 2 diabetes treated with rosiglitazone and pioglitazone