Illinois Institute of Technology

About: Illinois Institute of Technology is a education organization based out in Chicago, Illinois, United States. It is known for research contribution in the topics: Electric power system & Wireless network. The organization has 10188 authors who have published 21062 publications receiving 554178 citations. The organization is also known as: IIT & Illinois Tech.

Supervised and unsupervised methods for prostate cancer segmentation with multispectral MRI.

Abstract: Purpose: Magnetic resonance imaging(MRI) has been proposed as a promising alternative to transrectal ultrasound for the detection and localization of prostate cancer and fusing the information from multispectral MRimages is currently an active research area In this study, the goal is to develop automated methods that combine the pharmacokinetic parameters derived from dynamic contrast enhanced (DCE) MRI with quantitative T 2 MRI and diffusion weighted imaging (DWI) in contrast to most of the studies which were performed with human readers The main advantages of the automated methods are that the observer variability is removed and easily reproducible results can be efficiently obtained when the methods are applied to a test data The goal is also to compare the performance of automated supervised and unsupervised methods for prostate cancer localization with multispectral MRI Methods: The authors use multispectral MRI data from 20 patients with biopsy-confirmed prostate cancer patients, and the image set consists of parameters derived from T 2 , DWI, and DCE-MRI The authors utilize large margin classifiers for prostate cancer segmentation and compare them to an unsupervised method the authors have previously developed The authors also develop thresholding schemes to tune support vector machines (SVMs) and their probabilistic counterparts, relevance vector machines (RVMs), for an improved performance with respect to a selected criterion Moreover, the authors apply a thresholding method to make the unsupervised fuzzy Markov random fields method fully automatic Results: The authors have developed a supervised machine learning method that performs better than the previously developed unsupervised method and, additionally, have found that there is no significant difference between the SVM and RVM segmentation results The results also show that the proposed methods for threshold selection can be used to tune the automated segmentation methods to optimize results for certain criteria such as accuracy or sensitivity The test results of the automated algorithms indicate that using multispectral MRI improves prostate cancer segmentation performance when compared to single MRimages, a result similar to the human reader studies that were performed before Conclusions: The automated methods presented here can help diagnose and detect prostate cancer, and improve segmentation results For that purpose, multispectral MRI provides better information about cancer and normal regions in the prostate when compared to methods that use single MRI techniques; thus, the different MRI measurements provide complementary information in the automated methods Moreover, the use of supervised algorithms in such automated methods remain a good alternative to the use of unsupervised algorithms

Type i and type ii mechanisms in the photosensitized lysis of phosphatidylcholine liposomes by hematoporphyrin

Abstract: The lysis of phosphatidylcholine (PC) liposomes was sensitized to visible light (>500nm) by hematoporphyrin (HP) incorporated in the liposomes (0.09-1.5%, wt/wt) or in the external buffer (1-15 μM). The lytic mechanism changed from the Type II pathway mediated by singlet oxygen (1O2) at low HP concentrations to the anoxic, Type I pathway at high HP concentrations. Spectral measurements of HP in aqueous and organic solvents indicate that the HP was not aggregated (monomers and/or dimers) for Type II sensitization and aggregated for Type I conditions. High concentrations of azide (>0.1 M) or DABCO (>0.5 M) were protective with high HP concentration under oxic and anoxic conditions, which cannot involve the scavenging of 1O2. Feasible protective mechanisms are quenching of the HP triplet state by high azide and repair of the damaged membrane by DABCO via an electron transfer process. There was significant protection against lysis under Type I conditions by low concentrations of ferricyanide (>1 mM), indicative of an electron transfer mechanism. The incorporation of 22 mol % cholesterol in PC liposomes with 1% HP had no effect on the lytic efficiency for oxic and anoxic conditions. Dipalmitoylphosphatidylcholine liposomes incorporating 1% HP showed negligible photosensitized lysis at 50°C compared with PC liposomes with 1% HP at 25°C. The promotion of photosensitized lysis by hydrodynamic agitation observed in prior work with methylene blue (Grossweiner and Grossweiner, 1982) was significant with HP sensitization for both Type I and Type II conditions. Actinometry with PC liposomes incorporating 1% HP indicated that photosensitized lysis was very inefficient, requiring many absorbed quanta per lysed liposome. Preliminary experiments with crude hematoporphyrin derivative (Hpd) showed similar concentration effects on lytic efficiency, where PC liposomes incorporating 0.1% (wt/wt) Hpd were strongly sensitized by oxygen, whereas sensitization by oxygen was insignificant with 3.1% Hpd. The results with HP and crude Hpd indicate that lytic damage in a biomembrane does not necessarily require oxygenation.

Mechanistic transmission modeling of COVID-19 on the Diamond Princess cruise ship demonstrates the importance of aerosol transmission.

Abstract: Several lines of existing evidence support the possibility of airborne transmission of coronavirus disease 2019 (COVID-19) However, quantitative information on the relative importance of transmission pathways of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains limited To evaluate the relative importance of multiple transmission routes for SARS-CoV-2, we developed a modeling framework and leveraged detailed information available from the Diamond Princess cruise ship outbreak that occurred in early 2020 We modeled 21,600 scenarios to generate a matrix of solutions across a full range of assumptions for eight unknown or uncertain epidemic and mechanistic transmission factors A total of 132 model iterations met acceptability criteria (R 2 > 095 for modeled vs reported cumulative daily cases and R 2 > 0 for daily cases) Analyzing only these successful model iterations quantifies the likely contributions of each defined mode of transmission Mean estimates of the contributions of short-range, long-range, and fomite transmission modes to infected cases across the entire simulation period were 35%, 35%, and 30%, respectively Mean estimates of the contributions of larger respiratory droplets and smaller respiratory aerosols were 41% and 59%, respectively Our results demonstrate that aerosol inhalation was likely the dominant contributor to COVID-19 transmission among the passengers, even considering a conservative assumption of high ventilation rates and no air recirculation conditions for the cruise ship Moreover, close-range and long-range transmission likely contributed similarly to disease progression aboard the ship, with fomite transmission playing a smaller role The passenger quarantine also affected the importance of each mode, demonstrating the impacts of the interventions

Three programs that use mass approaches to challenge the stigma of mental illness.

Abstract: Stigma impedes the life opportunities of people with mental illness. Research suggests that stigma may be reduced by three approaches: protest, education, and contact. Three programs that adapt these approaches for mass audiences are described: StigmaBusters, which is a form of protest; Elimination of Barriers Initiative, which involves education or social marketing; and In Our Own Voice, which relies on direct contact between people with mental illness and the public. The authors review preliminary research that offers initial support for the feasibility and impact of these programs, with a particular focus on how the components of social marketing (problem identification, description of target audiences, development of the change technology, and process and outcome evaluation) can be adapted to antistigma campaigns.

Subject-Specific Myoelectric Pattern Classification of Functional Hand Movements for Stroke Survivors

Abstract: In this study, we developed a robust subject-specific electromyography (EMG) pattern classification technique to discriminate intended manual tasks from muscle activation patterns of stroke survivors. These classifications will enable volitional control of assistive devices, thereby improving their functionality. Twenty subjects with chronic hemiparesis participated in the study. Subjects were instructed to perform six functional tasks while their muscle activation patterns were recorded by ten surface electrodes placed on the forearm and hand of the impaired limb. In order to identify intended functional tasks, a pattern classifier using linear discriminant analysis was applied to the EMG feature vectors. The classification accuracy was mainly affected by the impairment level of the subject. Mean classification accuracy was 71.3% for moderately impaired subjects (Chedoke Stage of Hand 4 and 5), and 37.9% for severely impaired subjects (Chedoke Stage of Hand 2 and 3). Most misclassification occurred between grip tasks of similar nature, for example, among pinch, key, and three-fingered grips, or between cylindrical and spherical grips. EMG signals from the intrinsic hand muscles significantly contributed to the inter-task variability of the feature vectors, as assessed by the inter-task squared Euclidean distance, thereby indicating the importance of intrinsic hand muscles in functional manual tasks. This study demonstrated the feasibility of the EMG pattern classification technique to discern the intent of stroke survivors. Future work should concentrate on the construction of a subject-specific EMG classification paradigm that carefully considers both functional and physiological impairment characteristics of each subject in the target task selection and electrode placement procedures.