20,733 research outputs found
Remote Sensing of the Temperature during Magnetic Hyperthermia
The cancer therapy, magnetic hyperthermia, was proposed 60 years ago. Despite decades of efforts, this technique is still in its research stage. An ex-vivo experiment presented in Chapter 1 shows that one of the main barriers lies in its temperature measurement. The current gold standard is to insert a thermal probe into the target tumour. The measurement of which is invasive and point measurement only. Because of the inhomogeneous particle distribution, the accuracy of point measurement relies on accurate placement of the thermal probe, which is difficult to achieve. Thus, this study investigates two alternatives of point measurement. The first alternative is an existing technique, i.e., infra-red thermography and the second is a thermometry proposed in this study. The latter is termed as magnetic particle thermometry (MPT). Before discussing these two methods of temperature sensing, Chapter 2 reviews concepts such as the biological effects of heat, the mechanism of magnetic heating, and other remote sensing methods. Subsequent to this, Chapter 3 and Chapter 4 respectively present in-vitro and in-vivo experiments to evaluate the implementation of infra-red thermography in magnetic hyperthermia. In which, the effects of particle distribution and the thermal doses on hyperthermia are discussed. The result suggests that the infra-red thermography is applicable to studies involving subcutaneous tumours. When treating a deep-seated tumour, another sensing method is still desired. Chapter 5 then describes the principles of proposed MPT. The MPT assesses the average temperature of the target tumour by detecting the average temperature of the deposited magnetic nanoparticles. The MPT is possible because the temperature of magnetic nanoparticles would interfere the resonant frequency of the field applicator. By tracking the shift in resonant frequency of the field applicator, the average temperature of particles is estimated. The theory of which is carefully validated through a series of experiments presented in Chapter 6
COMPARING THE DIFFERENCE BETWEEN FRONT-LEG AND BACK-LEG ROUND-HOUSE KICKS ATIACKING MOVEMENT ABILITIES IIN TAEKWONDO
The purpose of this study is to compare front-leg and back-leg movement abilities in Taekwondo athletes with a weight level of less than 68 kg. Six male subjects (age: 19.8±1, height: 175.6±3.9, weight: 62.5±4.8) conducted back-leg attacking movements and front-leg attacking movements with their dominant leg. The back-leg attacking movements include back leg round-house kick and strike back round house kick. The front-leg attacking movements include front leg round-house kick and slide round-house kick. From statistics obtained, the kicking of relative force, compound acceleration, and tangential acceleration are better for back-leg attacking movements. However, front-leg attacking movements are better in tangential velocity. The range of waist a rotation and the flexibility of the hip joint are important to roundhouse kick techniques to the kinetic chain
Macroecological Patterns of Climatic Niche Breadth Variation in Lacertid Lizards
Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in climatic niche breadth in lacertid lizards to test the following three hypotheses about climatic niche widths. First, does a species’ temperature or precipitation niche breadth relate to its temperature or precipitation niche position (the mean value of annual mean temperature or annual precipitation across sampled localities in the range of each species)? Second, are there trade-offs between a species’ temperature niche breadth and precipitation niche breadth? Third, does a species’ temperature or precipitation niche breadth relate to altitude or latitude? We expect that: (1) species distributed in cold regions are specialized for low-temperature environments (i.e. narrow niche breadth center around low temperatures); (2) a negative relationship between species niche breadth on temperature and precipitation axes according to the trade-off hypothesis (i.e. species that tolerate a broad range of precipitation regimes cannot also tolerate a broad range of temperatures); (3) precipitation niche breadth decreases with altitude or latitude, whereas temperature climatic niche breadth increases with altitude or latitude. Based on the analytical results we found that: (1) temperature niche breadth and position are negatively related, while precipitation niche breadth and position are positively related; (2) there is no trade-off between temperature and precipitation niche breadths; and (3) temperature niche breadth and latitude/altitude are positively related, but precipitation niche breadth and latitude/altitude are not significantly related. Our results show many similarities with previous studies on climatic niche widths reported for amphibians and lizards, which provide further evidence that such macroecological patterns of variation in climatic niche breadths may be widespread
Bis(2,2′-bipyridyl)(dichloroacetato)copper(II) dichloroacetate dihydrate
In the title compound, [Cu(C2HCl2O2)(C10H8N2)2](C2HCl2O2)·2H2O, the CuII ion is bonded to two N,N′-bidentate 2,2′-bipyridyl ligands and one O-monodentate 2,2-dichloroacetate anion in a distorted CuON4 trigonal-bipyramidal geometry, with the O atom occupying an equatorial site. In the crystal, the components are linked by O—H⋯O and O—H⋯Cl hydrogen bonds
Association between urinary glyphosate levels and hand grip strength in a representative sample of US adults: NHANES 2013–2014
IntroductionGlyphosate, a widely utilized herbicide globally, has been linked to various health issues, including cancer, birth abnormalities, and reproductive issues. Additionally, there is growing experimental support indicating potential harm to skeletal muscles. Despite this, the impact of glyphosate on human muscle health remains unclear.MethodsWe examined information gathered from the 2013-2014 National Health and Nutrition Examination Survey (NHANES), which included 1466 adults aged 18 or older. Our primary aim was to investigate the relationship between glyphosate exposure and hand grip strength, as well as its influence on lean muscle mass.Results and discussionOur investigation uncovered a detrimental correlation between glyphosate exposure and all measures of grip strength, except for the second test of the first hand. Specifically, we observed a statistically significant adverse association between glyphosate exposure and combined grip strength, which is calculated as the sum of the highest readings from both hands (ß coefficient of −2.000, S.E. = 0.891, p = 0.040). We did not observe a significant correlation between glyphosate levels, lean muscle mass, and the likelihood of reaching maximum grip strength meeting sarcopenia criteria. Additionally, we observed an interaction between age and glyphosate, as well as between body mass index (BMI) and glyphosate, concerning the association with combined grip strength. In this comprehensive analysis of NHANES data, our study reveals a potential association between glyphosate exposure and hand grip strength in the adult population. Our findings suggest the need for deeper exploration into the health effects of glyphosate exposure and its impact on muscle strength, shedding light on possible public health concerns
Combining Strategies for Parallel Stochastic Approximation Monte Carlo Algorithm of Big Data
Modeling and mining with massive volumes of data have become popular in recent decades. However, it is difficult to analyze on a single commodity computer because the size of data is too large. Parallel computing is widely used. As a natural methodology, the divide-and-combine (D&C) method has been applied in parallel computing. The general method of D&C is to use MCMC algorithm in each divided data set. However, MCMC algorith is computationally expensive because it requires a large number of iterations and is prone to get trapped into local optima. On the other hand, Stochastic Approximation in Monte Carlo algorithm (SAMC), a very sophisticated algorithm in theory and applications, can avoid getting trapped into local optima and produce more accurate estimation than the conventional MCMC algorithm does. Motivated by the success of SAMC, we propose parallel SAMC algorithm that can be utilized on massive data and is workable in parallel computing. It can also be applied for model selection and optimization problem. The main challenge of the parallel SAMC algorithm is how to combine the results from each parallel subset. In this work, three strategies to overcome the combining difficulties are proposed. From the simulation results, these strategies result in significant time saving and accurate estimation.
Synthetic Aperture Radar Interferometry (InSAR) is a technique of analyzing deformation caused by geophysical processes. However, it is limited by signal losses which are from topographic residuals. In order to analyze the surface deformation, we have to distinguish signal losses. Many methods assume the noise has second order stationary structure without testing it. The objective of this study is to examine the second order stationary assumption for InSAR noise and develop a parametric nonstationary model in order to demonstrate the effect of making incorrect assumption on random field. It indicates that wrong stationary assumption will result in bias estimation and large variation
Early Social-Emotional Development and the Utility of a Social-Emotional Screening Tool for Toddlers in Taiwan
In Taiwan, the high prevalence of emotional and behavioral problems in children has increased public awareness of young children’s social-emotional development in recent years. Early identification of social-emotional delays for all young children, and subsequent early intervention (EI) with ongoing monitoring for children with special needs are critical. However, previous social norms regarding early mental health problems, the lack of social-emotional screening, and the scarcity of EI research on social-emotional development in Taiwan have resulted in lack of early social emotional screening and early identification. This study investigates toddler-aged children’s social-emotional development in Taiwan and monitors their social-emotional behaviors over time. Two hundred eighty-four children with and without development delays were screened with a social-emotional screening tool, the Traditional Chinese ASQ:SE-2, and then were subsequently followed for six months and retested. Findings indicated a high positive rate of social-emotional risk at 22.9% for 18-month-old children who were not receiving early intervention services, suggesting that additional numbers of children could be identified for EI services early on. Findings also indicated that children with developmental delays or disabilities were 3 to 4 times more likely to have social-emotional risk, and that the risk could increase overtime, emphasizing the needs for monitoring social-emotional behaviors and the effectiveness of interventions. To address early identification and ongoing monitoring, the present study suggests the use of the Traditional Chinese ASQ:SE-2 and needs further studies establishing psychometric evidence for toddlers in Taiwan
- …