6 research outputs found
CT Image Segmentation Based on clustering Methods.
Background: image processing of medical images is major method to increase reliability of cancer diagnosis.
Methods: The proposed system proceeded into two stages: First, enhancement stage which was performed using of median filter to reduce the noise and artifacts that present in a CT image of a human lung with a cancer, Second: implementation of k-means clustering algorithm.
Results: the result image of k-means algorithm compared with the image resulted from implementation of fuzzy c-means (FCM) algorithm.
Conclusion: We found that the time required for k-means algorithm implementation is less than that of FCM algorithm.MATLAB package (version 7.3) was used in writing the programming code of our work
Histological and Histomorphometric illustration the endochondral ossification of the mandibular angle defect repair in rats after oral stimulation with bisphosphonate treatment (an in vivo study)
Background: Bio-phosphonates can be used to lower the risk of hip and spine fractures. Additionally, they can be used to treat Paget's disease of the bones in a variety of dosages. In the procedure that replace hyaline cartilage to bone, this procedure i.e. called endochondral ossification. It starts when mesenchymal cells from the mesoderm develop into chondrocytes. Chondrocytes multiply quickly and release an extracellular matrix to create the cartilage that serves as the model for bone.
Objective: To histomorphometric illustration the endochondral ossification of the mandibular angle defect repair in rats after oral stimulation with bisphosphonate treatment.
Patients and Methods: 20 rats were used in this work and the animals were divided into the following groups: 10 Rats from the control group. The bone defect was healed naturally without medicament and 10 rats were used in the experiment, and taking the biophosphonate medication helped mend the bone defect. Every single group was studied in 7 and 14 day (5 rats for each healing period) and the surgical procedure was performed for histological and Histomorphometrically examination. The data analysis with spss statistic measure & with P vale (P ≤ 0.05).
Results: Active effect of the bio-phosphate medicament in the endochondral ossification and the cell that responsible for the cartilage formation and accelerated the healing of the mandibular defect with inhibition of the bone resoption and finally decrease the time that need to full healing.
Conclusion: The chemical medicament that represented by bio-phosphonate accelerated the endochondral ossification in a short time and replacement with bone in the site of the defect
Influence of Ectopic Beats on the Average, Maximum, and Minimum Heart Rates
Background: Heart rate metrics including the average heart rate, maximum heart rate, and minimum heart rate reflect the physiological condition of the heart. Clinically, determining the impact of ventricular and atrial ectopic beats on those three metrics is important because they indicate how hard the heart is working.
Objective: To investigate the changes in heart rates of ventricular and atrial ectopic patients.
Patients and Methods: In this study, data from 90 persons (30 with ventricular ectopic beats, 30 with atrial ectopic beats, and 30 healthy people) were gathered and analyzed to see what changes in heart rate metrics may occur in patients with ectopic beats.
Results: According to our results, the three heart rate metrics in almost all three groups are statistically insignificant (p-value > 0.05). The average heart rate was significantly higher (p<0.05) in ventricular ectopic patients than in atrial ectopic patients. The effect of age and gender on heart rate metrics were statistically assessed.
Conclusion: Despite the fact that no significant differences were found in all groups, there were certain differences that require further examination. One of the long-term objectives is to expand this study to incorporate electrocardiography (ECG) analysis in order to complete the comparison between the three groups
A comparative study of sleep and diurnal patterns in house mouse (Mus musculus) and spiny mouse (Acomys cahirinus)
Most published sleep studies use three species: human, house mouse, or Norway rat. The degree to which data from these species captures variability in mammalian sleep remains unclear. To gain insight into mammalian sleep diversity, we examined sleep architecture in the spiny basal murid rodent Acomys cahirinus. First, we used a piezoelectric system validated for Mus musculus to monitor sleep in both species. We also included wild M. musculus to control for alterations generated by laboratory-reared conditions for M. musculus. Using this comparative framework, we found that A. cahirinus, lab M. musculus, and wild M. musculus were primarily nocturnal, but exhibited distinct behavioral patterns. Although the activity of A. cahirinus increased sharply at dark onset, it decreased sharply just two hours later under group and individual housing conditions. To further characterize sleep patterns and sleep-related variables, we set up EEG/EMG and video recordings and found that A. cahirinus sleep significantly more than M. musculus, exhibit nearly three times more REM, and sleep almost exclusively with their eyes open. The observed differences in A. cahirinus sleep architecture raise questions about the evolutionary drivers of sleep behavior
A case for hybrid BCIs: combining optical and electrical modalities improves accuracy
Near-infrared spectroscopy (NIRS) is a promising research tool that found its way into the field of brain-computer interfacing (BCI). BCI is crucially dependent on maximized usability thus demanding lightweight, compact, and low-cost hardware. We designed, built, and validated a hybrid BCI system incorporating one optical and two electrical modalities ameliorating usability issues. The novel hardware consisted of a NIRS device integrated with an electroencephalography (EEG) system that used two different types of electrodes: Regular gelled gold disk electrodes and tri-polar concentric ring electrodes (TCRE). BCI experiments with 16 volunteers implemented a two-dimensional motor imagery paradigm in off- and online sessions. Various non-canonical signal processing methods were used to extract and classify useful features from EEG, tEEG (EEG through TCRE electrodes), and NIRS. Our analysis demonstrated evidence of improvement in classification accuracy when using the TCRE electrodes compared to disk electrodes and the NIRS system. Based on our synchronous hybrid recording system, we could show that the combination of NIRS-EEG-tEEG performed significantly better than either single modality only
Turning point in COVID-19 severity and fatality during the pandemic: a national cohort study in Qatar
Objective To assess the evolution of COVID-19 severity and fatality in a unique setting that consistently applied, throughout the pandemic, rigorous and standardised criteria for defining severe COVID-19 outcomes.
Methods and analysis We conducted a national cohort study on 312 109 Qatari citizens to investigate incidence of severe, critical or fatal COVID-19 classified according to the WHO criteria between 28 February 2020 and 21 April 2023. Incidence rates for severe, critical or fatal COVID-19 were estimated during the pre-omicron phase, first omicron wave, combined phases and throughout the pandemic.
Results Cumulative incidence of severe, critical or fatal COVID-19 after 3.14 years of follow-up was 0.45% (95% CI 0.43% to 0.47%). Incidence rate for severe, critical or fatal COVID-19 throughout the pandemic was 1.43 (95% CI 1.35 to 1.50) per 1000 person years. In the pre-omicron phase, first omicron wave, and combined phases, it was 2.01 (95% CI 1.90 to 2.13), 3.70 (95% CI 3.25 to 4.22) and 2.18 (95% CI 2.07 to 2.30) per 1000 person years, respectively. The post-first omicron phase saw a drastic drop to 0.10 (95% CI 0.08 to 0.14) per 1000 person years, a 95.4% reduction. Among all severe, critical and fatal cases, 99.5% occurred during the primary infection. Cumulative incidence of fatal COVID-19 was 0.042% (95% CI 0.036% to 0.050%), with an incidence rate of 0.13 (95% CI 0.11 to 0.16) per 1000 person years. In the post-first omicron phase, incidence rate of fatal COVID-19 decreased by 90.0% compared with earlier stages. Both severity and fatality exhibited an exponential increase with age and a linear increase with the number of coexisting conditions.
Conclusion The conclusion of the first omicron wave was a turning point in the severity of the pandemic. While vaccination and enhanced case management reduced severity gradually, the rapid accumulation of natural immunity during the first omicron wave appears to have played a critical role in driving this shift in severity.This work was possible through institutional salary support from the Biomedical Research Program and the Biostatistics, Epidemiology, and Biomathematics Research Core, both at Weill Cornell Medicine-Qatar, as well as institutional salary support provided by the Ministry of Public Health, Hamad Medical Corporation and Sidra Medicine. The authors are also grateful for the Qatar Genome Programme and Qatar University Biomedical Research Center for institutional support for the reagents needed for the viral genome sequencing. HHA acknowledges the support of Qatar University Internal Grant ID QUCG-CAS-23/24-114