Custom-developed Software Research Articles

Detection and quantification of gasping during resuscitation for out-of-hospital cardiac arrest

AimTo detect and quantify gasping during cardiopulmonary resuscitation (CPR) in out-of-hospital cardiac arrest (OHCA) patients and to investigate whether gasping is associated with increased return of spontaneous circulation (ROSC). Materials and methodsA prospective observational study in patients resuscitated and mechanically or manually ventilated for OHCA by emergency physicians of Ghent University Hospital. After intubation, pressure catheters were inserted in the endotracheal tube (ETT) and pressures were measured at the proximal and distal ends of the ETT. Gasping was analysed with custom-developed software and volumes were calculated based on pressure differences between the catheters. Data are expressed as median (interquartile range). ResultsData were collected in 292 resuscitated patients of whom 36.2% achieved ROSC. Seventy-six of 292 (26.0%) patients showed gasping on the pressure curves during resuscitation. The median gasping volume was 274ml (196–434). The median gasping rate was 3.7 gasps/min (1.5–7.3). Gasping occurred significantly more in patients displaying ventricular fibrillation as the initial rhythm compared to patients with pulseless electrical activity, pulseless ventricular tachycardia or asystole. The median gasping rate was significantly higher in the ROSC group compared to the non-ROSC group (11.8 gasps/min (95% CI [4.2, 13.9]) and 2.8 gasps/min (95% CI [1.7, 3.9]) respectively (P<0.001)). A gasping rate of >7.3 gasps/min appeared to be the optimal criterion value to herald ROSC. Deeper negative pressures were associated with an increased incidence of ROSC (P=0.011). There was no significant difference in ROSC between patients with gasping and those without. ConclusionThe occurrence of gasping during CPR was high. Significant gasping volumes were measured. The presence or absence of gasping was not associated with ROSC, but higher gasping rate and deeper negative pressures were.

Microvessel Chaste: An Open Library for Spatial Modeling of Vascularized Tissues

Spatial models of vascularized tissues are widely used in computational physiology. We introduce a software library for composing multiscale, multiphysics models for applications including tumor growth, angiogenesis, osteogenesis, coronary perfusion, and oxygen delivery. Composition of such models is time consuming, with many researchers writing custom software. Recent advances in imaging have produced detailed three-dimensional (3D) datasets of vascularized tissues at the scale of individual cells. To fully exploit such data there is an increasing need for software that allows user-friendly composition of efficient, 3D models of vascularized tissues, and comparison of predictions with in vivo or in vitro experiments and alternative computational formulations. Microvessel Chaste can be used to build simulations of vessel growth and adaptation in response to mechanical and chemical stimuli; intra- and extravascular transport of nutrients, growth factors and drugs; and cell proliferation in complex 3D geometries. In addition, it can be used to develop custom software for integrating modeling with experimental data processing workflows, facilitated by a comprehensive Python interface to solvers implemented in C++. This article links to two reproducible example problems, showing how the library can be used to build simulations of tumor growth and angiogenesis with realistic vessel networks.

Impact of Thoracic Endovascular Repair on Pulsatile Aortic Strain in Acute Type B Aortic Dissection: Preliminary Results.

The impact of thoracic endovascular aortic repair (TEVAR) on pulsatile aortic strain remains undetermined in patients with Type B aortic dissection (TBAD). Therefore, we quantified pulsatile aortic strain in TBAD patients and control subjects. We retrospectively analyzed two TBAD patients from our database with cardiac-gated computed tomography angiography imaging available before and after TEVAR and two control subjects (67- and 76-year-old males). Patient 1 (54-year-old female) presented with acute TBAD, and Patient 2 (55-year-old male) had Marfan syndrome and ruptured acute TBAD. Custom-developed software was used to compute aortic length, diameter, and area during the cardiac cycle. Pulsatile strain was calculated as systolic increments of length and circumference divided by corresponding diastolic values. Before TEVAR, pulsatile longitudinal strain of the thoracic aorta was lower in TBAD patients (1.4-1.7%) than in control subjects (2.1-4.5%). After TEVAR, pulsatile longitudinal strain increased proximal to the stent-graft by 65% in the arch of Patient 1 and by 70% in the ascending aorta of Patient 2. Pulsatile circumferential strain was elevated in false lumen patency (4.4-6.2%) compared with thrombosed false lumen (1.4-2.1%) or control subjects (0.9-3.3%). Following TEVAR, circumferential measurements within stented segments were deemed unreliable due to artifacts. TEVAR led to a considerable increase of pulsatile longitudinal strain proximal to the stent-grafts, and TBAD was associated with longitudinally stiffer aortas, which may be part of the pathophysiology of TEVAR-related complications such as retrograde dissection and aneurysmal dilatation. These preliminary data call for larger prospective studies.

Migrate, Publish, Repeat: TEI Journals in the Open Journal Systems Platform

The Indiana University (IU) Libraries have a long history of using the TEI markup standard to encode and publish electronic texts, but choosing the best publishing platform has been challenging for certain projects. Before formally launching an open access journal publishing program in 2008, the Libraries collaborated with two scholarly journals to provide open access publishing using P3 SGML and P4 XML TEI encoding delivered through the DSpace and XTF platforms. Both journals used complex encoding, transformation, and delivery workflows that required copious amounts of custom software development to function properly. As these systems aged, the time and effort required to maintain them steadily increased. In 2013, the Libraries began planning to migrate these journals into the Open Journal Systems (OJS)1 platform while preserving the TEI markup. Both journals are now publishing using the OJS platform. The Indiana Magazine of History2 was successfully launched in OJS in August 2014, and The Medieval Review3 was launched in June 2015. Publishing in this manner leverages the IU Libraries’ strengths in electronic text projects and XML workflows within an easy-to-use, flexible platform that journal editors appreciate. The success of these migrations presents a new framework for future XML publishing of open access journals at Indiana University.

Methodology for High-Throughput Field Phenotyping of Canopy Temperature Using Airborne Thermography.

Lower canopy temperature (CT), resulting from increased stomatal conductance, has been associated with increased yield in wheat. Historically, CT has been measured with hand-held infrared thermometers. Using the hand-held CT method on large field trials is problematic, mostly because measurements are confounded by temporal weather changes during the time required to measure all plots. The hand-held CT method is laborious and yet the resulting heritability low, thereby reducing confidence in selection in large scale breeding endeavors. We have developed a reliable and scalable crop phenotyping method for assessing CT in large field experiments. The method involves airborne thermography from a manned helicopter using a radiometrically-calibrated thermal camera. Thermal image data is acquired from large experiments in the order of seconds, thereby enabling simultaneous measurement of CT on potentially 1000s of plots. Effects of temporal weather variation when phenotyping large experiments using hand-held infrared thermometers are therefore reduced. The method is designed for cost-effective and large-scale use by the non-technical user and includes custom-developed software for data processing to obtain CT data on a single-plot basis for analysis. Broad-sense heritability was routinely >0.50, and as high as 0.79, for airborne thermography CT measured near anthesis on a wheat experiment comprising 768 plots of size 2 × 6 m. Image analysis based on the frequency distribution of temperature pixels to remove the possible influence of background soil did not improve broad-sense heritability. Total image acquisition and processing time was ca. 25 min and required only one person (excluding the helicopter pilot). The results indicate the potential to phenotype CT on large populations in genetics studies or for selection within a plant breeding program.

Recent Increases in Hippocampal Tau Pathology in the Aging Japanese Population: The Hisayama Study.

The Hisayama study is a prospective cohort study of lifestyle-related diseases that commenced in 1961. Through it, a significant increasing trend in the prevalence of Alzheimer's disease has been observed over the past 18 years. We sought to investigate the increases in brain pathology related to Alzheimer's disease using automated MATLAB morphometric analyses for quantifying tau pathology. We examined a series of autopsied cases from Hisayama residents obtained between 1998 and 2003 (group A: 203 cases), and between 2009 and 2014 (group B: 232 cases). We developed custom software in MATLAB to analyze abnormal tau deposits quantitatively. Specimens were immunostained with both anti-amyloid-β-protein and anti-phosphorylated tau antibodies. Both the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) criteria for senile plaques and Braak stage for NFT were higher in group B. Morphometric analyses of the hippocampi also revealed a trend toward increased tau pathology in both men and women over 80 years of age in group B. The increases were also significant when the subjects were examined independently according to high or low CERAD scores and in all levels of AD neuropathologic change according to the National Institute on Aging-Alzheimer's Association guidelines (2012). We revealed a recent trend of increased tauopathy in the older people, which is partly independent of amyloid-β pathology.

Effect of Posterior Malleolus Fracture on Syndesmosis Reduction

Category: Trauma Introduction/Purpose: Syndesmotic malreduction and the presence of posterior malleolus fractures negatively influence outcomes in rotational ankle fractures. While there are no universally accepted criteria for posterior malleolar fixation, it has recently been shown that posterior malleolar fixation contributed to the stability of the syndesmosis. However, little is known if and how anatomic or non-anatomic fixation of the posterior malleolus affects syndesmotic reduction. A study analyzing syndesmotic reduction in specimens with varying in size and quality of reduction of the posterior malleolus was conducted. Methods: Nine through-knee cadaveric specimens were randomized into two groups with small (a third of the fibular notch, n=4) and large (two-third of the fibular notch, n=5) posterior malleolar fragments. A model of stage IV supination external rotation injury after fibular repair was created by sharply releasing anterior inferior tibiofibular ligament, superficial and deep deltoid ligaments, and interosseous membrane. Posterior malleolar fracture with predefined sizing was created with preservation of posterior inferior tibiofibular ligament. High resolution CT scan was obtained in each specimen at the four stages; intact, neutral- axis syndesmotic clamping only, with anatomic fixation of the posterior malleolus, and with non-anatomic fixation of the posterior malleolus using a 4.8 mm interposed spacer. Measurement of syndesmotic reduction in both anteroposterior and mediolateral planes was made automatically using a validated technique assisted by custom-developed software at 1 cm proximal to the ankle joint. Results: The presence of either a neutral-axis clamping alone or with an anatomically reduced fracture fragment caused a slight anterior shift of the fibula that was more pronounced in the smaller fragment group. Two-way ANOVA indicated no significant effects of fragment size (p=0.73) or reduction (p=0.09) on AP fibular movement. However, presence of non-anatomical fixation caused the fibula to move significantly posteriorly in the presence of a large posterior malleolar fragment (p=0.03 and p=0.01 relative to the intact and clamping only states). In the mediolateral direction, a neutral-axis clamping alone and clamping with an anatomically reduced fracture fragment both increased medial translation of the distal fibula. The non-anatomic reduction model of the posterior malleolus associated with corresponding lateral displacement of the distal fibula. Conclusion: The overall anteroposterior reduction of the syndesmosis using neutral-axis clamping was generally not affected by posterior malleolar fracture except in a non-anatomic fixation of large fragments. Mediolateral syndesmotic reduction was affected by the conditions of posterior malleolar fixation with best results in anatomic fixation but the intact state was still not replicated. Malreduction of the posterior malleolus led to a corresponding syndesmotic malreduction. When a posterior malleolar fixation is indicated in cases with syndesmotic injury, anatomic fracture fixation is paramount as it can affect syndesmotic reduction especially with larger fragments.

An experimental investigation of the impact of thoracic endovascular aortic repair on longitudinal strain.

To investigate the impact of thoracic endovascular aortic repair (TEVAR) on longitudinal strain and assess aortic tensile properties in order to better understand complications associated with TEVAR. Twenty fresh thoracic porcine aortas were harvested and connected to a mock circulatory loop driven by a centrifugal flow pump at body temperature. Length measurements were conducted before and after TEVAR through aortic marking, high-definition imaging and custom-developed software under physiological pressure conditions (i.e. between 100 and 180 mmHg with 20 mmHg increments). Longitudinal strain was derived from length amplitude divided by the baseline length at 100 mmHg. Three groups of stent-graft oversizing were created (0-9, 10-19 and 20-29%). Finally, elastic properties of the aortic samples were assessed in both longitudinal and circumferential directions through uniaxial tensile testing. Longitudinal strain was compared before and after TEVAR, and stress-to-rupture was compared among specimens and locations. TEVAR induced a longitudinal strain decrease from 11.9 to 5.6% (P< 0.001) in the stented segments and a longitudinal strain mismatch between stented (5.6%) and non-stented segments (9.1%, P< 0.001). Stent-graft oversizing did not affect the magnitude of strain reduction (P= 0.77). Tensile testing showed that peak stress-to-rupture was lower for longitudinal (1.4 ± 0.4 MPa) than for circumferential fragments (2.3 ± 0.4 MPa, P< 0.001). In addition, longitudinal fragments were more prone to rupture proximally than distally (P= 0.01). This experimental study showed that TEVAR acutely stiffens the aorta in the longitudinal direction and thereby induces a strain mismatch, while tensile testing confirmed that longitudinal aortic fragments are most prone to rupture, particularly close to the arch. Such an acute strain mismatch of potentially vulnerable tissue might play a role in TEVAR-related complications, including retrograde dissection and aneurysm formation. The finding that TEVAR stiffens the aorta longitudinally may also shed light on systemic complications following TEVAR, such as hypertension and cardiac remodelling. These observations may imply the need for further improvement of stent-graft designs.

A Portable Low-Power Acquisition System with a Urease Bioelectrochemical Sensor for Potentiometric Detection of Urea Concentrations.

This paper presents a portable low-power battery-driven bioelectrochemical signal acquisition system for urea detection. The proposed design has several advantages, including high performance, low cost, low-power consumption, and high portability. A LT1789-1 low-supply-voltage instrumentation amplifier (IA) was used to measure and amplify the open-circuit potential (OCP) between the working and reference electrodes. An MSP430 micro-controller was programmed to process and transduce the signals to the custom-developed software by ZigBee RF module in wireless mode and UART in able mode. The immobilized urease sensor was prepared by embedding urease into the polymer (aniline-co-o-phenylenediamine) polymeric matrix and then coating/depositing it onto a MEMS-fabricated Au working electrode. The linear correlation established between the urea concentration and the potentiometric change is in the urea concentrations range of 3.16 × 10−4 to 3.16 × 10−2 M with a sensitivity of 31.12 mV/log [M] and a precision of 0.995 (R2 = 0.995). This portable device not only detects urea concentrations, but can also operate continuously with a 3.7 V rechargeab-le lithium-ion battery (500 mA·h) for at least four days. Accordingly, its use is feasible and even promising for home-care applications.

Nanoscale Measurements of Biochemical Interactions at the Surface of Optically Trapped Particles

Molecular interactions at biological surfaces are central to numerous physiological functions, such as cell-cell communication, adhesion, or the immune response to pathogens. Most analyses of these interactions require the use of purified proteins, which are studied in suspension or after immobilization on artificial carrier objects. To characterize instead biomolecular dynamics directly at the surface of small biological particles, we have combined optical tweezers with a multi-channel microfluidics chamber. This instrument allows us to expose a laser-trapped particle to a series of microenvironments that are created without walls by laminar flow. We monitor biochemical reactions between the particle surface and supplied ligands by measuring minuscule changes in the particle's response to a well-defined fluidic drag force. Among others, this response is highly sensitive to the particle size. Once a particle is trapped in a typical experiment, the chamber is moved perpendicularly to the main flow direction in a sinusoidal wave to apply a periodic drag force. Using custom-developed software, the resulting particle motion is tracked with a resolution of ∼5 nm at a rate of up to 3,200 frames per second. A linear-systems analysis allows us to monitor the particle radius in different environments with a resolution of a few nanometers. In first measurements, we used this setup to examine the interaction between protein-A and human IgG. We found that at saturation, bound IgG added an apparent thickness of 12.6±1.4(SD) nm to protein-A-coated beads, in agreement with the expected size of human IgG of ∼12 nm. Moreover, we measured an equilibrium constant of KA = 0.115 nM−1 for the protein-A:IgG interaction, in excellent agreement with literature values.

An interactive videogame designed to improve respiratory navigator efficiency in children undergoing cardiovascular magnetic resonance.

BackgroundAdvanced cardiovascular magnetic resonance (CMR) acquisitions often require long scan durations that necessitate respiratory navigator gating. The tradeoff of navigator gating is reduced scan efficiency, particularly when the patient’s breathing patterns are inconsistent, as is commonly seen in children. We hypothesized that engaging pediatric participants with a navigator-controlled videogame to help control breathing patterns would improve navigator efficiency and maintain image quality.MethodsWe developed custom software that processed the Siemens respiratory navigator image in real-time during CMR and represented diaphragm position using a cartoon avatar, which was projected to the participant in the scanner as visual feedback. The game incentivized children to breathe such that the avatar was positioned within the navigator acceptance window (±3 mm) throughout image acquisition.Using a 3T Siemens Tim Trio, 50 children (Age: 14 ± 3 years, 48 % female) with no significant past medical history underwent a respiratory navigator-gated 2D spiral cine displacement encoding with stimulated echoes (DENSE) CMR acquisition first with no feedback (NF) and then with the feedback game (FG). Thirty of the 50 children were randomized to undergo extensive off-scanner training with the FG using a MRI simulator, or no off-scanner training. Navigator efficiency, signal-to-noise ratio (SNR), and global left-ventricular strains were determined for each participant and compared.ResultsUsing the FG improved average navigator efficiency from 33 ± 15 to 58 ± 13 % (p < 0.001) and improved SNR by 5 % (p = 0.01) compared to acquisitions with NF. There was no difference in navigator efficiency (p = 0.90) or SNR (p = 0.77) between untrained and trained participants for FG acquisitions. Circumferential and radial strains derived from FG acquisitions were slightly reduced compared to NF acquisitions (−16 ± 2 % vs −17 ± 2 %, p < 0.001; 40 ± 10 % vs 44 ± 11 %, p = 0.005, respectively). There were no differences in longitudinal strain (p = 0.38).ConclusionsUse of a respiratory navigator feedback game during navigator-gated CMR improved navigator efficiency in children from 33 to 58 %. This improved efficiency was associated with a 5 % increase in SNR for spiral cine DENSE. Extensive off-scanner training was not required to achieve the improvement in navigator efficiency.Electronic supplementary materialThe online version of this article (doi:10.1186/s12968-016-0272-z) contains supplementary material, which is available to authorized users.

Application of weight bearing biplanar stereoradiography in assessment of lower limb deformity

Background: The purpose of this study was to investigate the agreement between the three-dimensional (3D) weight-bearing radiological measurements of leg deformities in the presence of leg rotation and knee flexion in a biplanar stereoradiography system (EOS imaging) and measurements of computed tomography (CT) scans. Methods: Upright biplanar X-rays of six Sawbones; with deformity were registered in no flexion/rotation angle, in 10° and 20° of axial rotation, and 10° and 20° of knee flexion. A CT scan of each bone was registered in supine position, and the 3D reconstruction of each bone was generated. Two-dimensional (2D) lengths and deformity angles were measured on the plain X-rays by two independent observers. Two independent observers generated the 3D reconstructions of the biplanar X-rays and the leg deformity parameters were measured in 3D using custom-developed software. 2D and 3D measurements were compared to CT measurements performed by two observers and repeated three times. The intraclass correlation and limit of agreement between the three measurement techniques were evaluated using Bland-Altman plots. Results: The intraclass correlations were good to excellent for the three imaging modalities (intraclass correlation coefficients = 0.71-0.95). Frontal deformity angles and lengths were significantly different in the 2D X-rays and CT (P 0.05). Conclusions: The 3D measurements of the weight-bearing biplanar X-rays were comparable to 3D CT in assessment of the lower limb deformity.

The Undiagnosed Diseases Program Integrated Collaboration System (UDPICS): One Program's Experience Developing Custom Software to Support Research for Complex-Disease Families.

The Undiagnosed Diseases Program (UDP) was started in 2008 with the goals of making diagnoses and facilitating related translational research. The individuals and families seen by the UDP are often unique and medically complex. Approximately 40% of UDP cases are pediatric. The Undiagnosed Diseases Program Integrated Collaboration System (UDPICS) was designed to create a collaborative workspace for researchers, clinicians and families. We describe our progress in developing the system to date, focusing on design rationale, challenges and issues that are likely to be common in the development of similar systems in the future.

Analyzing Structure and Function of Vascularization in Engineered Bone Tissue by Video-Rate Intravital Microscopy and 3D Image Processing.

Vascularization is a key challenge in tissue engineering. Three-dimensional structure and microcirculation are two fundamental parameters for evaluating vascularization. Microscopic techniques with cellular level resolution, fast continuous observation, and robust 3D postimage processing are essential for evaluation, but have not been applied previously because of technical difficulties. In this study, we report novel video-rate confocal microscopy and 3D postimage processing techniques to accomplish this goal. In an immune-deficient mouse model, vascularized bone tissue was successfully engineered using human bone marrow mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) in a poly (D,L-lactide-co-glycolide) (PLGA) scaffold. Video-rate (30 FPS) intravital confocal microscopy was applied in vitro and in vivo to visualize the vascular structure in the engineered bone and the microcirculation of the blood cells. Postimage processing was applied to perform 3D image reconstruction, by analyzing microvascular networks and calculating blood cell viscosity. The 3D volume reconstructed images show that the hMSCs served as pericytes stabilizing the microvascular network formed by HUVECs. Using orthogonal imaging reconstruction and transparency adjustment, both the vessel structure and blood cells within the vessel lumen were visualized. Network length, network intersections, and intersection densities were successfully computed using our custom-developed software. Viscosity analysis of the blood cells provided functional evaluation of the microcirculation. These results show that by 8 weeks, the blood vessels in peripheral areas function quite similarly to the host vessels. However, the viscosity drops about fourfold where it is only 0.8 mm away from the host. In summary, we developed novel techniques combining intravital microscopy and 3D image processing to analyze the vascularization in engineered bone. These techniques have broad applicability for evaluating vascularization in other engineered tissues as well.

New software applications for interchangeable instrumentation in spinal stereotaxis.

Computer image-guided surgery has been widely accepted because it allows the surgeon to track an instrument through unvisualized critical structures of a patient in real-time, thus minimizing the risk of injury. Current spinal and cranial image-guided surgery is, however, limited by the lack of surgical instruments and software applications that would allow rapid interchange of useful instruments to perform the procedures. Most image-guided systems utilize a single standard probe or a few pre-defined instruments that are not necessarily useful for performing the actual surgical procedure. Present image-guided technology for screw placement in spinal surgery utilizes the standard probe only to confirm the entry point location and view the planned trajectory of the screw. The surgeon then resumes the procedure using standard surgical instruments to drill, tap and place screws without the benefit of image guidance. Our clinical laboratory experience with spinal image-guided surgery indicates that there is potential for error between each of these procedural steps of screw placement. Despite accurately locating an entry point, any deviation in the trajectory during drilling of a pilot hole, tapping or screw placement may result in significant errors in screw placement and potential neurovascular injury. We have developed custom software applications and universal hardware adaptation devices for spinal image-guided surgery that allow the use of standard instruments for intraoperative guidance. Utilizing universal dynamic registration hardware and software, standard surgical instruments are adapted for real-time image guided surgery. An array of light emitting diodes can be attached to essentially any rigid instrument with a definable tip and then calibrated to the system for intraoperative use. Laboratory tests using a cadaveric model indicate a difference in accuracy of less than 1.0 mm between the standard probe and a dynamically registered custom instrument and an absolute mean error of less than 2.0 mm for the image-guided system which is clinically insignificant in most cases. This technology is a significant step forward as it allows the surgeon to use a full array of instruments with image guidance and will ultimately make spinal and intracranial surgery safer and more accurate.

Quantification of plant chlorophyll content using Google Glass.

Measuring plant chlorophyll concentration is a well-known and commonly used method in agriculture and environmental applications for monitoring plant health, which also correlates with many other plant parameters including, e.g., carotenoids, nitrogen, maximum green fluorescence, etc. Direct chlorophyll measurement using chemical extraction is destructive, complex and time-consuming, which has led to the development of mobile optical readers, providing non-destructive but at the same time relatively expensive tools for evaluation of plant chlorophyll levels. Here we demonstrate accurate measurement of chlorophyll concentration in plant leaves using Google Glass and a custom-developed software application together with a cost-effective leaf holder and multi-spectral illuminator device. Two images, taken using Google Glass, of a leaf placed in our portable illuminator device under red and white (i.e., broadband) light-emitting-diode (LED) illumination are uploaded to our servers for remote digital processing and chlorophyll quantification, with results returned to the user in less than 10 seconds. Intensity measurements extracted from the uploaded images are mapped against gold-standard colorimetric measurements made through a commercially available reader to generate calibration curves for plant leaf chlorophyll concentration. Using five plant species to calibrate our system, we demonstrate that our approach can accurately and rapidly estimate chlorophyll concentration of fifteen different plant species under both indoor and outdoor lighting conditions. This Google Glass based chlorophyll measurement platform can display the results in spatiotemporal and tabular forms and would be highly useful for monitoring of plant health in environmental and agriculture related applications, including e.g., urban plant monitoring, indirect measurements of the effects of climate change, and as an early indicator for water, soil, and air quality degradation.

Diseño del modelo integral colaborativo para el desarrollo ágil de software en las empresas de la zona centro-occidente en México

El principal problema en el desarrollo de software es generar aplicaciones que no acaban satisfaciendo las necesidades y objetivos de las organizaciones (clientes). El desarrollo de software en la actualidad no impacta directamente a los objetivos y metas que tienen planeadas las organizaciones, es decir el software se desarrolla por expertos de tecnologías de la información (TI) que se dedican a realizar los procesos de análisis, diseño y desarrollo para la creación de nuevas herramientas tecnológicas (software). Sin embargo, no se hacen acompañar por expertos de los procesos de la organización que contribuyan al óptimo funcionamiento del software. Dichos desarrollos deben de estar respaldados y basarse en algún modelo o metodología que ayude a generar software de calidad, en donde el grupo multidisciplinario que interviene en el desarrollo del software no acabe trabajando para la metodología elegida, sino la metodología para el proyecto. De ahí la necesidad de generar modelos que ayuden a las pequeñas y medianas empresas de México al desarrollo pertinente de software a la medida. Este estudio propone un modelo para el desarrollo ágil de software, el cual se basa en la percepción de expertos en esta área. El modelo que se propone a continuación se denomina “Modelo de desarrollo de software integral colaborativo” (MDSIC) y ofrece a los expertos una manera sencilla de interactuar con él a través de cinco niveles que brindan las mejores prácticas en el desarrollo de software; además dichos niveles consideran las funciones principales que propone el Project Management Institute (PMI), lo que permite generar software de calidad alineado con los objetivos de la organización (planeación estratégica). El MDSIC evalúa la calidad del software a través de una serie de indicadores que se deben de contemplar para el óptimo funcionamiento de un software, estos indicadores están fundamentados por estándares de calidad en el software. Por último el MDSIC busca generar una base de conocimientos a través del social business apoyándose de las redes sociales y con ello generar un banco de información con las opiniones y experiencias de los expertos en el desarrollo de software, permitiendo las mejores prácticas en el desarrollo de proyectos de software.

Control devices and steering strategies in pathway surgery

For pathway surgery, that is, minimally invasive procedures carried out transluminally or through instrument-created pathways, handheld maneuverable instruments are being developed. As the accompanying control interfaces of such instruments have not been optimized for intuitive manipulation, we investigated the effect of control mode (1DoF or 2DoF), and control device (joystick or handgrip) on human performance in a navigation task. The experiments were conducted using the Endo-PaC (Endoscopic-Path Controller), a simulator that emulates the shaft and handle of a maneuverable instrument, combined with custom-developed software animating pathway surgical scenarios. Participants were asked to guide a virtual instrument without collisions toward a target located at the end of a virtual curved tunnel. The performance was assessed in terms of task completion time, path length traveled by the virtual instrument, motion smoothness, collision metrics, subjective workload, and personal preference. The results indicate that 2DoF control leads to faster task completion and fewer collisions with the tunnel wall combined with a strong subjective preference compared with 1DoF control. Handgrip control appeared to be more intuitive to master than joystick control. However, the participants experienced greater physical demand and had longer path lengths with handgrip than joystick control.

Three-dimensional modelling and concurrent measurements of root anatomy in mandibular first molar mesial roots using micro-computed tomography.

To obtain concurrent radicular measurements in the mesiobuccal (MB) and mesiolingual (ML) canals of mandibular first molars using scanned data of micro-computed tomography (μCT) with novel software. The scanned data from 37 mandibular first molar mesial roots were reconstructed and analysed with custom-developed software (Kappa2). For each canal, three-dimensional (3D) surface models were re-sliced at 0.1-mm intervals perpendicular to the central axis. Dentine thicknesses, canal widths and 3D curvatures were measured automatically on each slice. Measurements were analysed statistically with anova for differences at each direction and at different levels of both canals. Lateral dentine thicknesses were significantly higher than mesial and distal thicknesses, at all the levels of both canals (P<0.001). Mesial thicknesses were significantly higher than distal thicknesses in the coronal third of both canals (P<0.001). Thinnest dentine thicknesses were mainly located on the disto-inside of both canals. Narrowest canal widths were 0.24±0.10 and 0.22±0.09mm in MB and ML canals, respectively. Canal curvatures were greatest in the apical third of both canals (P<0.001), and they were greater in the MB canals than in the ML canals (P<0.05). Micro-computed tomography with novel software provided valuable anatomical information for optimizing instrumentation and minimizing mishaps in nonsurgical root canal treatment.

Identificación de variables que afectarían la valoración de productos de las micro, pequeñas y medianas empresas dedicadas al desarrollo de software por encargo en Colombia

El presente trabajo se realizó con el fin de identificar las variables (necesidades y factores) que podrían afectar la valoración de productos de las micro, pequeñas y medianas empresas (Mipymes) dedicadas al desarrollo de software por encargo en Colombia para los años 2014-2018. Dicha identificación se realizó de manera colectiva mediante un proceso de reflexión, concertación y aplicación de herramientas prospectivas. Se analizó el comportamiento de la industria de software en el país, que es relativamente reciente. El Ministerio de Tecnologías de la Información y las Comunicaciones actualmente impulsa nuevas estrategias para su fortalecimiento. Para desarrollar este trabajo se utilizaron herramientas metodológicas prospectivas, a fin de hacer un diagnóstico de la situación, identificar los actores implicados y revisar las tendencias pertinentes. Como herramientas se seleccionaron el taller de prospectiva estratégica y el método Delphi. Con base en los resultados obtenidos, se recomienda generar estrategias dentro de las Mipymes desarrolladoras de software por encargo que permita a dichas empresas: (1) aprovechar mejor el apoyo ofrecido por el gobierno por medio de las leyes de emprendimiento y algunos beneficios tributarios; (2) generar innovación que les permita volverse competitivas; (3) gestionar el conocimiento de tal forma que éste quede documentado y no se cometan los mismos errores del pasado;(4) revisar los modelos económicos actuales ya que estos son poco eficientes, lo que lleva a que muchas de estas empresas se vuelvan inviables financieramente; y (5) realizar adaptaciones tecnológicas acompañadas de transferencia tecnológica y capacitación del recurso humano, de tal forma que se permita una evolución en el tiempo de las compañías y del capital humano.