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Quantitative analysis evaluation of image reconstruction algorithms between digital and analog PET-CT
No full textPositron emission tomography – computed tomography (PET-CT) is a non-invasive diagnostic tool that is widely used in oncology imaging. High quality diagnostic images and quantitative accuracy are often restricted by image noise, adequate spatial resolution and contrast ratio.
Ordered Subset Expectation Maximisation (OSEM) is a widely used statistical iterative reconstruction algorithm in PET-CT due to its dependability, reconstruction quality and adequate signal-to-noise ratio. However, OSEM requires a large number of iterations to achieve high quantitative accuracy which results in increasing image noise. A novel algorithm, HYPER DPR (developed by United Imaging Healthcare) is an artificial intelligence-based reconstruction method that aims to provide increased sensitivity, higher spatial resolution and less noise.
This study evaluates the accuracy and sensitivity of HYPER DPR against OSEM using reconstructed images from analog and digital PET-CT. Results demonstrate that both OSEM and HYPER DPR reconstruction algorithms in digital PET-CT has greater spatial resolution, increased detection sensitivity and less image noise when compared to analog PET-CT. Digital PET-CT and HYPER DPR enables better small lesion detection and increased resolution, thus resulting in better disease detection and improved patient management. Increased sensitivity of digital PET-CT results in low dose scans from reduced radiotracer injections, therefore having higher patient output
Generalized Fibonacci search for optimization of unconstrained one-and two-dimensional unimodal functions
No full textUndeniably, optimization problems of smooth functions have been extensively investigated by many researchers with the use of calculus throughout the years. On the contrary, most practical problems involve the optimization of non-smooth or discontinuous functions, which may require non-calculus methods. One approach is the Fibonacci Search. This study investigates the minimization of the unconstrained one- and two-dimensional unimodal functions by generalizing the Fibonacci Search. In the first part of this research, we begin with the investigation of line search methods using Fibonacci numbers on one-dimensional unimodal functions, f(x). Starting from a fixed point, we use the Initial Interval Search to create an initial interval to bound the global optimum of f(x). Next, we consider the “ratio length of 1” from the conventional Fibonacci Search to implement a different approach to the Fibonacci Search by taking the lower successive Fibonacci numbers as the initial ratios with specifying the number of iterations to be used beforehand, where the number of iterations to achieve the optimum nth sub-Fibonacci number, Sn(a,b,p,q), where a,b ∈Z+∪{0} and p,q ∈Z+ such that S0 = a, S1=b and Sn+2=pSn+1 + qSn, for n≥0, a+b>0, and q=2p2−1. Furthermore, we generate possible combinations of a, b, p and q to guarantee the achievement the optimum of f(x). Due to the efficiency, the optimistic nth sub-Fibonacci number, Sn(a=1,b=3,p=2,q=7) is chosen, and we name this number as Fibo1327. Next, we execute the Bracketing Search to narrow the interval of uncertainty by developing a macro program in Microsoft Excel to optimize several one-dimensional benchmark functions. Using the same width of the initial interval and based on the necessary and sufficient conditions, the Fibo1327 Search requires less iterations to achieve the approximate optimum and out-performs the Golden Section Search and other Fibonacci-like Search methods such as the Fibonacci, Lucas and Pell approaches. In the second part of this research, we introduce a new search method, namely the Swing Descent method by extending the Generalized Fibonacci Search to solve a two-dimensional unimodal function, f(x,y). The Swing Descent method also involves the use of Initial Interval and Bracketing searches. Without knowing an initial domain that bounds the global optimum point, the Swing Descent method only needs the initial point on f(x,y) and the initial
step sizes along the x- and y-axes. We develop a macro program in Microsoft Excel to execute the algorithm of the Swing Descent method to optimize a number of two-dimensional benchmark functions. From the initial point, together with the Fibo1327 Search and the subsequent step sizes produced recursively from the initial step sizes, the Swing Descent method is repeated iteratively on the cross-sectional functions along the x- and y-axes, until the desired approximate optimum of f(x,y) is reached within the
boundary restricted by the tolerance. It performed effectively in locating the approximate optimum point. We conclude that the optimization problem of one- and two-dimensional unimodal functions, whether smooth or non-smooth, continuous or discontinuous, can be solved approximately by the Generalized Fibonacci Search
Six Strategies for Optimizing Linear Growth through Improving Awareness of Breastfeeding, Dietary Diversity in Complementary Feeding, and Growth Monitoring during Early Life
Get PDFOnly one-fourth of the countries under the Sustainable Development Goal are ‘on track’ to reduce the burden of malnutrition as of 2020. A deficit in linear growth during the first 5 years of life is mainly due to growth faltering in the first 1000 days. This deficit has been consistently reported to be linked to suboptimal cognitive neurodevelopment, while its improvement in early childhood has been reported to offer an opportunity for rescuing neurocognitive potential. This paper describes the perspectives of multidisciplinary experts, representing a range of disciplines related to child growth and nutrition, from Nigeria, Indonesia, and Malaysia, who convened virtually to review and discuss measures aimed at preventing a further increase in growth faltering, including stunting, among children aged 0-3 years under the current prevailing circumstances. Based on the latest evidence of practices and knowledge, the expert panel proposed six strategies to support linear growth in early life which consists of 2 new initiatives: 1) increasing peer-to-peer knowledge transfer among HCP via digital engagement; 2) increasing knowledge transfer from HCPs to caregivers via social media; while maintaining the existing strategies: 1) stimulating initiatives to support breastfeeding during the first 6 months of life; 2) improving quality of complementary feeding; 3) strengthening growth monitoring to detect suboptimal growth in early childhood; 4) optimizing public-private engagement. The recommended solutions presented herein are the culmination of the collective insights of the expert panel. These recommendations offer invaluable approaches on addressing the critical public health issue of malnutrition, specifically growth faltering, and can benefit not only the three countries concerned but also other low and middle-income countries facing similar nutritional challenges
E-cigarettes endanger users and non-users
No full textWhile cigarette smoking poses health risks, second-hand smoke exposure is also harmful to our health
Keep vape liquids away from children
No full textIt is important for parents to tell their children about the dangers of vapes and eliquids
Kerjasama saintis, media sosial mampu cetus kesedaran krisis global
No full textPada Januari lalu, saya menghadiri mesyuarat tahunan Forum Ekonomi Dunia (WEF) di Davos. Walaupun terdapat sesetengah pihak mempertikaikan merit WEF, hakikatnya di forum antarabangsa inilah, kadangkala sesuatu perkara dapat Berjaya dilaksanakan
Assessment of occupational exposure from PET and PET/CT scanning in Saudi Arabia
No full textNuclear medicine diagnostic procedures such as positron emission tomography (PET) scans and hybrid imaging using a combination of PET and computed tomography (CT), commonly referred to as PET-CT scanning. Hybrid imaging, which allows accurate visualization of internal anatomical structure and the consequent physiological processes simultaneously, is extensively used in oncology and other departments. Nevertheless, this exposes patients and medical personnel in such departments to significant doses of ionizing radiation, especially in hybrid imaging, where two sources of radiation (the radiopharmaceutical infusion and the CT scanner) are used. This necessitates strict compliance with international guidelines and regulations on radiation protection. Recent reports showed that occupational staff exposure might exceed the annual dose limits. This study evaluated occupational exposure associated with diagnostic hybrid PET-CT imaging and the consequent risks. Twenty medical personnel: 5 physicists, ten technologists, two medical doctors, and three nurses are included in this study. The assessment includes measuring occupational ambient doses using calibrated optical stimulating-luminescent dosimeters (OSL)(Al2O3:C). These badges were read using an automatic OSL reader. The results, displayed as (mean ± standard deviation): (range) of the effective dose (mSv) for the different personnel, can be summarized as follows(mean standard deviation and range). Physicists 0.72 ± 0.14 (0.49–0.83) mSv in 2019 and 0.67 ± 0.07 (0.59–0.78) in 2020; technologist 1.4 ± 0.96 (0–3.27) mSv in 2019 and 1.395 ± 1.27 (0.64–4.36) mSv; medical doctors 0.445 ± 0.42 (0.15–0.74) mSv in 2019 and 0.70 ± 0.04 (0.67–0.73) in 2020; and nurses 1.38 ± 0.25 (1.21–1.66) mSv in 2019 and 1.41 ± 0.17 (1.23–1.55) in 2020. The tube voltage of the scanner used in this study had a constant value of 120 kVp for all patients. Staff working in PET or PET-CT departments receive significant doses from the radiopharmaceuticals and the energetic gamma rays from the CT scanners. Hence, optimizing the CT acquisition parameter is necessary to optimize the occupational doses and restrict them to acceptable dose limits
Thermoluminescence kinetic parameters of proton-irradiated germanium doped flat-shape optical fibres
No full textGlow curve is a key element in thermoluminescence (TL) studies as it provides on-the-ground understanding on the trapping mechanism inside the crystal lattice and hence stability of the TL material. In the present work, luminescence mechanism of the in-house fabricated germanium doped (Ge-doped) flat-shape silica optical fibres have been investigated following irradiation by 150-MeV proton beams. Results of TL dose-response showed that there is a linear relationship between TL response and proton doses from 1 to 10 Gy, with a coefficient of determination close to one. The structure of glow curve remains unchanged throughout the studied dose range with a maximum glow peak dominated at temperature of within 250–290 ◦C. A Tmax-Tstop plot reveals not only horizontal regions but also smooth slopes, indicative of the presence of a continuum distribution of glow peaks and trap depth. A computerised glow curve deconvolution analysis of the respective fibre glow-curves demonstrated that they were composed of five strongly overlapping peaks underlying a broad TL spectrum, obtaining figures of merit in the range of 0.56–1.64%. The main physical kinetic parameters (activation energy and frequency factor) of the fitted glow peaks were obtained using GlowFit software. The data suggest that the TL glow peaks of the Ge-doped silica optical fibres obey second-order kinetics
Physical, structural, elastic and optical investigations on Dy3+ ions doped boro-tellurite glasses for radiation attenuation application
No full textA set of Dy3+ ions doped boro-tellurite glasses is prepared using the melt quenching method and its radiation resisting aptitude is estimated through various structural and elastic features. The results were interpreted due to the effect of TeO2 concentration in the glass systems. The observed molar volume (Vm) values reduced with the rise in the tellurium content with the creation of more bridging oxygens in the structure. The cross-link density rises the rigidity of the glass and its density. Additionally, boron-boron separation and tellurium-tellurium separation, and optical band gap were computed to prove the connectivity of the system which is noted to reduce with the rise in the tellurium content. Glass with 40% TeO2 is observed to hold high elastic moduli and consequently high density and connectivity which are vital requirements for effective radiation shielding. Moreover, the Monte Carlo N-Particle transport code version 5 is used to qualify the γ-ray shielding properties. The qualification of the shielding properties showed that the linear attenuation coefficient was enhanced by a factor of 80% from 0.248 c
A comprehensive perspective of traditional Arabic or Islamic medicinal plants as an adjuvant therapy against COVID-19
Get PDFCOVID-19 is a pulmonary disease caused by SARS-CoV-2. More than 200 million individuals are infected by this globally. Pyrexia, coughing, shortness of breath, headaches, diarrhoea, sore throats, and body aches are among the typical symptoms of COVID-19. The virus enters into the host body by interacting with the ACE2 receptor. Despite many SARS-CoV-2 vaccines manufactured by distinct strategies but any evidence-based particular medication to combat COVID-19 is not available yet. However, further research is required to determine the safety and effectiveness profile of the present therapeutic approaches. In this study, we provide a summary of Traditional Arabic or Islamic medicinal (TAIM) plants’ historical use and their present role as adjuvant therapy for COVID-19. Herein, six medicinal plants Aloe barbadensis Miller, Olea europaea, Trigonella foenum-graecum, Nigella sativa, Cassia angustifolia, and Ficus carica have been studied based upon their pharmacological activities against viral infections. These plants include phytochemicals that have antiviral, immunomodulatory, antiasthmatic, antipyretic, and antitussive properties. These bioactive substances could be employed to control symptoms and enhance the development of a possible COVID-19 medicinal synthesis. To determine whether or if these TAIMs may be used as adjuvant therapy and are appropriate, a detailed evaluation is advised