27 research outputs found
The effect of earnings management on liquidity criteria and lack of liquidity stock
Liquidity criteria that investors in making portfolio investments are involved. Among the factors that could affect liquidity, earnings management. Earnings management can accrual-based earnings management aspects and management of real benefit to be evaluated; Therefore, the aim of this study is to estimate the accrual-based earnings management and gain real management and its effects on liquidity of companies listed on the Stock Exchange in Tehran. The sample consisted of 78 companies for the period 2008 to 2012. We used multivariate regression model based on panel data is performed. Our results show that research hypotheses are tested between accrual-based earnings management positive and significant relationship with the lack of liquidity, and the liquidity and significant negative relationship. As well as the actual management of non-profit with a positive and significant relationship between stock liquidity, and the liquidity is insignificant and there is a negative relationship
DeePLT: Personalized Lighting Facilitates by Trajectory Prediction of Recognized Residents in the Smart Home
In recent years, the intelligence of various parts of the home has become one
of the essential features of any modern home. One of these parts is the
intelligence lighting system that personalizes the light for each person. This
paper proposes an intelligent system based on machine learning that
personalizes lighting in the instant future location of a recognized user,
inferred by trajectory prediction. Our proposed system consists of the
following modules: (I) human detection to detect and localize the person in
each given video frame, (II) face recognition to identify the detected person,
(III) human tracking to track the person in the sequence of video frames and
(IV) trajectory prediction to forecast the future location of the user in the
environment using Inverse Reinforcement Learning. The proposed method provides
a unique profile for each person, including specifications, face images, and
custom lighting settings. This profile is used in the lighting adjustment
process. Unlike other methods that consider constant lighting for every person,
our system can apply each 'person's desired lighting in terms of color and
light intensity without direct user intervention. Therefore, the lighting is
adjusted with higher speed and better efficiency. In addition, the predicted
trajectory path makes the proposed system apply the desired lighting, creating
more pleasant and comfortable conditions for the home residents. In the
experimental results, the system applied the desired lighting in an average
time of 1.4 seconds from the moment of entry, as well as a performance of
22.1mAp in human detection, 95.12% accuracy in face recognition, 93.3% MDP in
human tracking, and 10.80 MinADE20, 18.55 MinFDE20, 15.8 MinADE5 and 30.50
MinFDE5 in trajectory prediction
Prevalence of Shielding in Diagnostic X-ray Centers in the Islamic Republic of Iran: A Systematic Review
Shielding has been recommended as an effective tool against radiation exposure. Several studies have published on the availability and use of shielding tools in diagnostic X-ray centers across the country and contradictory results been reported. Therefore, the aim of this systematic review was to find out the status of radiation protection in term of availability and use of shielding tools in diagnostic X-ray centers in Iran. An extensive literature search was conducted in the PubMed/Medline, Embase, ISI, Cochrane Library, SID, Magiran, IranMedex, Irandoc and Google-Scholar search engine. We also manually searched the reference lists of the relevant studies. Two authors independently assessed the eligibility of all studies and extracted data. Thirty-seven studies published from 1998 to 2019 were included in this systematic review. In all, 1089 diagnostic X-ray centers, 4439 radiographs and performance of 1472 radiographers were covered in these studies. The availability of lead apron, gonad shield and thyroid collar were ranged from 7 to 95.5%, 26.6 to 94% and 7 to 94%, respectively. Moreover, their usage was ranged from 0 to 85.5%, 0 to 35% and 0 to 38.4%, respectively. In addition, lens shield was discussed in one study with availability of 0%. During 1998 to 2019, the status of shielding had not improved across the country. Therefore adherence to the safety guideline as far as possible is required to protection patients from undue exposure to radiation
Prevalence of Shielding in Diagnostic X-ray Centers in the Islamic Republic of Iran: A Systematic Review
Shielding has been recommended as an effective tool against radiation exposure. Several studies have published on the availability and use of shielding tools in diagnostic X-ray centers across the country and contradictory results been reported. Therefore, the aim of this systematic review was to find out the status of radiation protection in term of availability and use of shielding tools in diagnostic X-ray centers in Iran. An extensive literature search was conducted in the PubMed/Medline, Embase, ISI, Cochrane Library, SID, Magiran, IranMedex, Irandoc and Google-Scholar search engine. We also manually searched the reference lists of the relevant studies. Two authors independently assessed the eligibility of all studies and extracted data. Thirty-seven studies published from 1998 to 2019 were included in this systematic review. In all, 1089 diagnostic X-ray centers, 4439 radiographs and performance of 1472 radiographers were covered in these studies. The availability of lead apron, gonad shield and thyroid collar were ranged from 7 to 95.5%, 26.6 to 94% and 7 to 94%, respectively. Moreover, their usage was ranged from 0 to 85.5%, 0 to 35% and 0 to 38.4%, respectively. In addition, lens shield was discussed in one study with availability of 0%. During 1998 to 2019, the status of shielding had not improved across the country. Therefore adherence to the safety guideline as far as possible is required to protection patients from undue exposure to radiation
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
Live Single Cell Imaging and Analysis Using Microfluidic Devices
Today many cell biological techniques study large cell populations where an average estimate of individual cells’ behavior is observed. On the other hand, single cell analysis is required for studying functional heterogeneities between cells within populations. This thesis presents work that combines the use of microfluidic devices, optical microscopy and automated image analysis to design various cell biological assays with single cell resolution including cell proliferation, clonal expansion, cell migration, cell-cell interaction and cell viability tracking. In fact, automated high throughput single cell techniques enable new studies in cell biology which are not possible with conventional techniques. In order to automatically track dynamic behavior of single cells, we developed a microwell based device as well as a droplet microfluidic platform. These high throughput microfluidic assays allow automated time-lapse imaging of encapsulated single cells in micro droplets or confined cells inside microwells. Algorithms for automatic quantification of cells in individual microwells and micro droplets are developed and used for the analysis of cell viability and clonal expansion. The automatic counting protocols include several image analysis steps, e.g. segmentation, feature extraction and classification. The automatic quantification results were evaluated by comparing with manual counting and revealed a high success rate. In combination these automatic cell counting protocols and our microfluidic platforms can provide statistical information to better understand behavior of cells at the individual level under various conditions or treatments in vitro exemplified by the analysis of function and regulation of immune cells. Thus, together these tools can be used for developing new cellular imaging assays with resolution at the single cell level. To automatically characterize transient migration behavior of natural killer (NK) cells compartmentalized in microwells, we developed a method for single cell tracking. Time-lapse imaging showed that the NK cells often exhibited periods of high motility, interrupted with periods of slow migration or complete arrest. These transient migration arrest periods (TMAPs) often overlapped with periods of conjugations between NK cells and target cells. Such conjugation periods sometimes led to cell-mediated killing of target cells. Analysis of cytotoxic response of NK cells revealed that a small sub-class of NK cells called serial killers was able to kill several target cells. In order to determine a starting time point for cell-cell interaction, a novel technique based on ultrasound was developed to aggregate NK and target cells into the center of the microwells. Therefore, these assays can be used to automatically and rapidly assess functional and migration behavior of cells to detect differences between health and disease or the influence of drugs. The work presented in this thesis gives good examples of how microfluidic devices combined with automated imaging and image analysis can be helpful to address cell biological questions where single cell resolution is necessary. QC 20130927</p
Live Single Cell Imaging and Analysis Using Microfluidic Devices
Today many cell biological techniques study large cell populations where an average estimate of individual cells’ behavior is observed. On the other hand, single cell analysis is required for studying functional heterogeneities between cells within populations. This thesis presents work that combines the use of microfluidic devices, optical microscopy and automated image analysis to design various cell biological assays with single cell resolution including cell proliferation, clonal expansion, cell migration, cell-cell interaction and cell viability tracking. In fact, automated high throughput single cell techniques enable new studies in cell biology which are not possible with conventional techniques. In order to automatically track dynamic behavior of single cells, we developed a microwell based device as well as a droplet microfluidic platform. These high throughput microfluidic assays allow automated time-lapse imaging of encapsulated single cells in micro droplets or confined cells inside microwells. Algorithms for automatic quantification of cells in individual microwells and micro droplets are developed and used for the analysis of cell viability and clonal expansion. The automatic counting protocols include several image analysis steps, e.g. segmentation, feature extraction and classification. The automatic quantification results were evaluated by comparing with manual counting and revealed a high success rate. In combination these automatic cell counting protocols and our microfluidic platforms can provide statistical information to better understand behavior of cells at the individual level under various conditions or treatments in vitro exemplified by the analysis of function and regulation of immune cells. Thus, together these tools can be used for developing new cellular imaging assays with resolution at the single cell level. To automatically characterize transient migration behavior of natural killer (NK) cells compartmentalized in microwells, we developed a method for single cell tracking. Time-lapse imaging showed that the NK cells often exhibited periods of high motility, interrupted with periods of slow migration or complete arrest. These transient migration arrest periods (TMAPs) often overlapped with periods of conjugations between NK cells and target cells. Such conjugation periods sometimes led to cell-mediated killing of target cells. Analysis of cytotoxic response of NK cells revealed that a small sub-class of NK cells called serial killers was able to kill several target cells. In order to determine a starting time point for cell-cell interaction, a novel technique based on ultrasound was developed to aggregate NK and target cells into the center of the microwells. Therefore, these assays can be used to automatically and rapidly assess functional and migration behavior of cells to detect differences between health and disease or the influence of drugs. The work presented in this thesis gives good examples of how microfluidic devices combined with automated imaging and image analysis can be helpful to address cell biological questions where single cell resolution is necessary. QC 20130927</p
Classification of microwave scattering data with application to detection of bleeding stroke
Offline signature verification using geometric center features
A modified offline signal verification method based on geometric centre has been presented in this paper. The aim is to distinguish if a signature is forgery or original. The method is based on geometric center features. After vertical and horizontal splitting of figure around its geometric center, Euclidean distance model was used for classification and then algorithm based on diagonal splitting is presented too. The overall system performance is considered in term of well defined measure quantities
Classification of Microwave Scattering Data based on a Subspace Distance with Application to Detection of Bleeding Stroke
This paper demonstrates the usefulness of a classifier based on a subspace distance for the detection of bleeding stroke based on microwave scattering measurements from an antenna array placed around the skull. This discriminating classifier is suitable for high dimensional data applications when the number of training data samples is less than the data dimension. The proposed classifier was
tested on both clinical and experimental data to separate bleeding subjects from non-bleeding ones. A pseudo-inverse Mahalanobis distance based classifier and a classifier based on the Euclidean distance were used on clinical data for the purpose of comparison with the proposed classifier