Comparison of Regional Lung Deformation Between Dynamic and Static CT Imagery Using Inverse Consistent Registration

2009 ◽  
Author(s):  
Ryan Amelon ◽  
Kai Ding ◽  
Kunlin Cao ◽  
Gary E. Christensen ◽  
Joseph M. Reinhardt ◽  
...  
Keyword(s):  
Image Data ◽  
Lung Mechanics ◽  
Ct Scans ◽  
Positive Pressure ◽  
Displacement Fields ◽  
Regional Patterns ◽  
Recent Developments ◽  
The Difference ◽  
Key Aspects ◽  
Lung Deformation

The mechanics of lung deformation is traditionally assessed at a whole-lung or lobar level. We submit that key aspects of lung mechanics maybe better understood by studying regional patterns of lung deformation by leveraging recent developments in tomographic imaging and image processing techniques. Our group has developed an inverse consistent registration technique for estimating local displacement distributions from paired lung CT volumes [1,2]. This facilitates the estimation of strain distributions and consequently, the regional patterns in volume change and its preferential directionalities (anisotropy in deformation). In this study, we use this novel method to compare regional deformation in the lungs between static and dynamic inflations in an adult sheep. Much of our research has focused on registration of static lung images at different positive end-expiratory pressures (PEEP). More recently, respiratory-gated CT scans of supine, positive-pressure inflated sheep lungs have been gathered in order to compare the displacement fields of a dynamically inflating lung to the static lung scans. The theory is that scanning a dynamically inflating lung will more accurately reflect natural deformation during breathing by realizing time-dependent mechanical properties (viscoelasticity). The downside to human dynamic lung imaging is the increased radiation dose necessary to acquire the image data across the respiratory cycle, though low-dose CT scans are an option [3]. This experiment observed the difference in strain distribution between dynamically inflated lungs versus static apneic lungs using the inverse consistent image registration developed in our lab.

scholarly journals Russia’s Foreign Policy Evolution in the New Balkan Landscape

2020 ◽  
Vol 56 (3-4) ◽  
pp. 179-199
Author(s):  
Ekaterina Entina ◽  
Alexander Pivovarenko
Keyword(s):  
Foreign Policy ◽  
Soviet Union ◽  
Regional Security ◽  
Southeast Europe ◽  
The Balkans ◽  
Current Trends ◽  
The Soviet Union ◽  
Recent Developments ◽  
The Difference

The article reflects on the issue of the foreign policy strategy of modern Russia in the Balkans region. One of the most significant aspects of this problem is the difference in views between Russia and the West. Authors show how different interpretations of the events in former Yugoslavia in the 1990s and the beginning of the 2000s predetermined the sense of mutual suspicion and mistrust which spread to other regions such as the post-Soviet space. Exploring differences between the Russian and the Western (Euro-Atlantic) views on the current matters, authors draw attention to fundamental differences in terminology: while the Western narrative promotes more narrow geographical and political definitions (such as the Western Balkan Six), traditional Russian experts are more inclined to wider or integral definitions such as “the Balkans” and “Central and Southeast Europe”. Meanwhile none of these terms are applicable for analysis of the current trends such as the growing transit role of the Balkans region and its embedding in the European regional security architecture. Therefore, a new definition is needed to overcome the differences in vision and better understand significant recent developments in the region. Conceptualizing major foreign policy events in Central and Southeast Europe during the last three decades (the 1990s, 2000s and 2010s), authors demonstrate the significance of differences in tools and methods between the Soviet Union and the modern Russia. Permanent need for adaptation to changing political and security context led to inconsistence in Russian Balkan policy in the 1990s. Nevertheless, Russia was able to preserve an integral vision of the region and even to elaborate new transregional constructive projects, which in right political circumstances may promote stability and become beneficial for both Russia and the Euro-Atlantic community.

scholarly journals Cardiac Organoids to Model and Heal Heart Failure and Cardiomyopathies

Biomedicines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 563
Author(s):  
Magali Seguret ◽  
Eva Vermersch ◽  
Charlène Jouve ◽  
Jean-Sébastien Hulot
Keyword(s):  
Tissue Engineering ◽  
Drug Testing ◽  
Cardiac Tissue ◽  
Cardiac Tissue Engineering ◽  
Cardiac Cells ◽  
Cardiac Functions ◽  
Different Types ◽  
Recent Developments ◽  
Human Cardiac Tissue ◽  
Key Aspects

Cardiac tissue engineering aims at creating contractile structures that can optimally reproduce the features of human cardiac tissue. These constructs are becoming valuable tools to model some of the cardiac functions, to set preclinical platforms for drug testing, or to alternatively be used as therapies for cardiac repair approaches. Most of the recent developments in cardiac tissue engineering have been made possible by important advances regarding the efficient generation of cardiac cells from pluripotent stem cells and the use of novel biomaterials and microfabrication methods. Different combinations of cells, biomaterials, scaffolds, and geometries are however possible, which results in different types of structures with gradual complexities and abilities to mimic the native cardiac tissue. Here, we intend to cover key aspects of tissue engineering applied to cardiology and the consequent development of cardiac organoids. This review presents various facets of the construction of human cardiac 3D constructs, from the choice of the components to their patterning, the final geometry of generated tissues, and the subsequent readouts and applications to model and treat cardiac diseases.

scholarly journals Experimental Models for Studying HPV-Positive and HPV-Negative Penile Cancer: New Tools for An Old Disease

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 460
Author(s):  
Beatriz Medeiros-Fonseca ◽  
Antonio Cubilla ◽  
Haissa Brito ◽  
Tânia Martins ◽  
Rui Medeiros ◽  
...  
Keyword(s):  
Mouse Models ◽  
Cell Lines ◽  
Penile Cancer ◽  
Hpv Infection ◽  
Experimental Models ◽  
In Vivo Models ◽  
Recent Developments ◽  
Key Aspects

Penile cancer is an uncommon malignancy that occurs most frequently in developing countries. Two pathways for penile carcinogenesis are currently recognized: one driven by human papillomavirus (HPV) infection and another HPV-independent route, associated with chronic inflammation. Progress on the clinical management of this disease has been slow, partly due to the lack of preclinical models for translational research. However, exciting recent developments are changing this landscape, with new in vitro and in vivo models becoming available. These include mouse models for HPV+ and HPV− penile cancer and multiple cell lines representing HPV− lesions. The present review addresses these new advances, summarizing available models, comparing their characteristics and potential uses and discussing areas that require further improvement. Recent breakthroughs achieved using these models are also discussed, particularly those developments pertaining to HPV-driven cancer. Two key aspects that still require improvement are the establishment of cell lines that can represent HPV+ penile carcinomas and the development of mouse models to study metastatic disease. Overall, the growing array of in vitro and in vivo models for penile cancer provides new and useful tools for researchers in the field and is expected to accelerate pre-clinical research on this disease.

Radiation exposure during the treatment of spinal deformities

2021 ◽  
pp. 1-7
Author(s):  
Jwalant S. Mehta ◽  
Kirsten Hodgson ◽  
Lu Yiping ◽  
James Swee Beng Kho ◽  
Ravindra Thimmaiah ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Ionizing Radiation ◽  
Effective Dose ◽  
Spinal Deformity ◽  
Background Radiation ◽  
Ct Scans ◽  
Intraoperative Fluoroscopy ◽  
The Difference ◽  
Risk Of Cancer ◽  
Surgical Group

Aims To benchmark the radiation dose to patients during the course of treatment for a spinal deformity. Methods Our radiation dose database identified 25,745 exposures of 6,017 children (under 18 years of age) and adults treated for a spinal deformity between 1 January 2008 and 31 December 2016. Patients were divided into surgical (974 patients) and non-surgical (5,043 patients) cohorts. We documented the number and doses of ionizing radiation imaging events (radiographs, CT scans, or intraoperative fluoroscopy) for each patient. All the doses for plain radiographs, CT scans, and intraoperative fluoroscopy were combined into a single effective dose by a medical physicist (milliSivert (mSv)). Results There were more ionizing radiation-based imaging events and higher radiation dose exposures in the surgical group than in the non-surgical group (p < 0.001). The difference in effective dose for children between the surgical and non-surgical groups was statistically significant, the surgical group being significantly higher (p < 0.001). This led to a higher estimated risk of cancer induction for the surgical group (1:222 surgical vs 1:1,418 non-surgical). However, the dose difference for adults was not statistically different between the surgical and non-surgical groups. In all cases the effective dose received by all cohorts was significantly higher than that from exposure to natural background radiation. Conclusion The treatment of spinal deformity is radiation-heavy. The dose exposure is several times higher when surgical treatment is undertaken. Clinicians should be aware of this and review their practices in order to reduce the radiation dose where possible.

scholarly journals Reproducibility of a new classification of the anterior clinoid process of the sphenoid bone

2020 ◽  
Vol 11 ◽  
pp. 281
Author(s):  
Feres Chaddad-Neto ◽  
Marcos Devanir Silva da Costa ◽  
Bruno Santos ◽  
Ricardo Lourenco Caramanti ◽  
Bruno Lourenco Costa ◽  
...  
Keyword(s):  
Interobserver Agreement ◽  
Anatomical Variation ◽  
Ct Scans ◽  
Multiplanar Reconstruction ◽  
Kappa Index ◽  
Anterior Clinoid Process ◽  
Kappa Test ◽  
Optic Strut ◽  
The Difference

Background: Pneumatization of the anterior clinoid process (ACP) affects paraclinoid region surgery, this anatomical variation occurs in 6.6–27.7% of individuals, making its preoperative recognition essential given the need for correction based on the anatomy of the pneumatized process. This study was conducted to evaluate the reproducibility of an optic strut-based ACP pneumatization classification by presenting radiological examinations to a group of surgeons. Methods: Thirty cranial computer tomography (CT) scans performed from 2013 to 2014 were selected for analysis by neurosurgery residents and neurosurgeons. The evaluators received Google Forms with questionnaires on each scan, DICOM files to be manipulated in the Horos software for multiplanar reconstruction, and a collection of slides demonstrating the steps for classifying each type of ACP pneumatization. Interobserver agreement was calculated by the Fleiss kappa test. Results: Thirty CT scans were analyzed by 37 evaluators, of whom 20 were neurosurgery residents and 17 were neurosurgeons. The overall reproducibility of the ACP pneumatization classification showed a Fleiss kappa index of 0.49 (95% confidence interval: 0.49–0.50). The interobserver agreement indices for the residents and neurosurgeons were 0.52 (0.51–0.53) and 0.49 (0.48–0.50), respectively, and the difference was statistically significant (P < 0.00001). Conclusion: The optic strut-based classification of ACP pneumatization showed acceptable concordance. Minor differences were observed in the agreement between the residents and neurosurgeons. These differences could be explained by the residents’ presumably higher familiarity with multiplanar reconstruction software.

scholarly journals Modeling the mind: Assessment of if…then… profiles as a window to shared and idiosyncratic psychological processes

2021 ◽  
Author(s):  
Vivian Zayas ◽  
Randy T. Lee ◽  
Yuichi Shoda
Keyword(s):  
Social Cognitive ◽  
Processing System ◽  
Cognitive Tasks ◽  
Affective Processing ◽  
Causal Inferences ◽  
Causal Processes ◽  
Recent Developments ◽  
Key Aspects ◽  
The Mind ◽  
Personality System

People’s behavior is characterized by stable if…then… profiles, or if in x situation then behavior a, but if in y situation then behavior b. But how do researchers conceptualize and measure if…then… profiles? Drawing from Cognitive-Affective Processing System (CAPS) theory, we discuss recent developments in assessing if…then… profiles, and how such profiles can provide a window for elucidating key aspects of the underlying personality system. Specifically, the Highly-Repeated Within-Person (HRWP) approach assesses how a behavior varies as a function of key features in a situation, and operationalizes if…then… profiles as regression betas. We illustrate how the HRWP approach can be applied to data from often-used social cognitive tasks, wherein an individual is exposed to a large number of situations that differ on a dimension that has been experimentally-manipulated by the researcher, and their behaviors to the situations are tracked. The HRWP approach allows researchers to more precisely assess a given individual’s if…then… pattern, make stronger causal inferences about a given individual’s personality system, and empirically investigate, rather than simply assume, if there are meaningful differences between individuals in the causal processes.

scholarly journals DETECTION OF CRACKS IN PAVED ROAD SURFACE USING LASER SCAN IMAGE DATA

2016 ◽  
Vol XLI-B1 ◽  
pp. 559-562 ◽  
Author(s):  
J. Choi ◽  
L. Zhu ◽  
H. Kurosu
Keyword(s):  
Image Segmentation ◽  
Background Subtraction ◽  
Three Dimensional ◽  
Laser Scanner ◽  
Image Data ◽  
Road Surface ◽  
Surface Model ◽  
Rolling Ball ◽  
The Difference ◽  
Paved Road

In the current study, we developed a methodology for detecting cracks in the surface of paved road using 3D digital surface model of road created by measuring with three-dimensional laser scanner which works on the basis of the light-section method automatically. For the detection of cracks from the imagery data of the model, the background subtraction method (Rolling Ball Background Subtraction Algorithm) was applied to the data for filtering out the background noise originating from the undulation and gradual slope and also for filtering the ruts that were caused by wearing, aging and excessive use of road and other reasons. We confirmed the influence from the difference in height (depth) caused by forgoing reasons included in a data can be reduced significantly at this stage. Various parameters of ball radius were applied for checking how the result of data obtained with this process vary according to the change of parameter and it becomes clear that there are not important differences by the change of parameters if they are in a certain range radius. And then, image segmentation was performed by multi-resolution segmentation based on the object-based image analysis technique. The parameters for the image segmentation, scale, pixel value (height/depth) and the compactness of objects were used. For the classification of cracks in the database, the height, length and other geometric property are used and we confirmed the method is useful for the detection of cracks in a paved road surface.

scholarly journals Anticoagulant effects of different calcium supplementation pathways in calcium-free RCA-CVVH: a study protocol for a prospective randomized cross-over trial

2019 ◽  
Author(s):  
Biantong JIANG ◽  
Zhigang ZHANG ◽  
Xiu JIN ◽  
Haiye WANG ◽  
Yuchen WU ◽  
...  
Keyword(s):  
Renal Replacement Therapy ◽  
Calcium Ions ◽  
Calcium Supplementation ◽  
Incidence Rates ◽  
Regional Citrate Anticoagulation ◽  
Citrate Anticoagulation ◽  
Catheter Dysfunction ◽  
Calcium Effect ◽  
The Difference ◽  
Key Aspects

Abstract Background When regional citrate anticoagulation used in continuous renal replacement therapy, one of the key aspects to achieve safe and effective extracorporeal circulation is the management of calcium ions. For calcium-free RCA-CVVH, the anticoagulant effects of different calcium supplementation pathways have not yet been explored. In this trial, we would test our hypothesis that compared with the SCV, when calcium was infused through the VL-FV, the arterial iCa2+ was lower. Methods This is a prospective randomized cross-over trial involving 24 patients undergoing RCA-CVVH. The patients were randomly divided into two groups: VL-FV—SCV group and SCV—VL-FV group. The difference of iCa2+ between arterial iCa2+ and post-filtration iCa2+ was compared. Secondary indicators included the incidence rates of catheter dysfunction and hypocalcemia. Discussion This is the first trial on the anticoagulant effects of calcium-free RCA-CVVH through different calcium supplement routes. We will confirm that the arterial iCa2 + level is slightly lower when calcium is infused in the VL-FV than in the SCV, and the incidence rates of catheter dysfunction and hypocalcemia will help us to determine which site is safer. Trial Registration CHiCTR registry: ChiCTR1800020046. Registered on 12 December 2018. (http://www.chictr.org.cn/listbycreater.aspx). Keywords: Continuous venous-venous hemofiltration, regional citrate anticoagulation, calcium, effect, safety, cross-over trial

Isotopy invariants of topological spaces

1960 ◽  
Vol 255 (1282) ◽  
pp. 331-366 ◽  
Keyword(s):  
Homotopy Type ◽  
Algebraic Topology ◽  
Complete System ◽  
Topological Spaces ◽  
Recent Developments ◽  
The Difference ◽  
Linear Graphs ◽  
Homotopy Invariants ◽  
General Method

A few decades ago, topologists had already emphasized the difference between homotopy and isotopy. However, recent developments in algebraic topology are almost exclusively on the side of homotopy. Since a complete system of homotopy invariants has been obtained by Postnikov, it seems that hereafter we should pay more attention to isotopy invariants and new efforts should be made to attack the classical problems. The purpose of this paper is to introduce and study new algebraic isotopy invariants of spaces. A general method of constructing these invariants is given by means of a class of functors called isotopy functors. Special isotopy functors are constructed in this paper, namely, the m th residual functor R m and the m th. enveloping functor E m . Applications of these isotopy invariants to linear graphs are given in the last two sections. It turns out that these invariants can distinguish various spaces belonging to the same homotopy type.

Prevalence Of Intra – Axial Versus Extra – Axial Hemorrhage In The Setting Of Head Trauma Using Computed Tomography

2021 ◽  
Vol 23 (09) ◽  
pp. 292-302
Author(s):  
Karthik Krishna Ramakrishnan ◽  
◽  
Vettrivizhi Sampath Arutperumselvi ◽  
Pavankumar Mathapathi ◽  
Praveen K. Sharma ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Head Injury ◽  
Tamil Nadu ◽  
Image Data ◽  
High Sensitivity ◽  
Cost Effective ◽  
Health Concern ◽  
Ct Scans ◽  
Traumatic Head Injury ◽  
Arachnoid Hemorrhage

Traumatic Brain Injury presents a global health concern, as it has become one of the leading causes of death and disability worldwide. Non-contrast head computed tomography (CT) scans have been used widely as a diagnostic tool in acute head injury because they are cost-effective, widely available, and detect haemorrhages with high sensitivity. We aimed to study the prevalence of intra and extra axial haemorrhages in patients presenting with head injury in and around Kanchipuram district of Tamil Nadu and also to further identify the commoner types of intracranial haemorrhages associated with such injuries. A retrospective observational study was conducted in the Department Of Radiology, Saveetha Medical College and Hospital for a period of 6 months. Image data from CT scans of the brain were obtained for 50 patients presenting with skull trauma and clinical suspicion of intracranial haemorrhage during the time period from January 2020 to May 2020 and were studied. Based on our study, out of the 50 subjects included it was observed that in the setting of traumatic head injury extra axial hemorrhages are more common than intra axial hemorrhages. Among the type of extra axial hemorrhage , extra dural hemorrhage was far more common than subdural and sub arachnoid hemorrhage especially in presence of skull fractures.

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