Arterial pulse wave analysis in time and frequency domain was carried out to find out biophysical and functional properties of artery walls measured with a photoplethysmographic (PPG) device. Because peripheral arterial disease (PAD) is a fatal problem all over the world, an easy diagnosis method would be needed. It could probably be diagnosed by PPG which is a non-invasive optical technique for detecting the arterial pulse waves. We present a study to characterize and quantify the arterial pulse wave components based on the use of logarithmic normal function (LNF). The measurements were carried out parallel from the index finger and toe tip with healthy subjects. In addition, a second derivative of the PPG signal (SNPPG) was also analyzed. The tests were applied to arterial pulse waves from 11 subjects between 5 and 69 years. The results show good correlation of pulse wave changes as a function of age.
{"title":"Estimation of biophysical and functional properties of artery walls from pulse wave measured by photoplethysmography","authors":"M. Huotari, Kari Määttä, J. Kostamovaara","doi":"10.2495/EHR110391","DOIUrl":"https://doi.org/10.2495/EHR110391","url":null,"abstract":"Arterial pulse wave analysis in time and frequency domain was carried out to find out biophysical and functional properties of artery walls measured with a photoplethysmographic (PPG) device. Because peripheral arterial disease (PAD) is a fatal problem all over the world, an easy diagnosis method would be needed. It could probably be diagnosed by PPG which is a non-invasive optical technique for detecting the arterial pulse waves. We present a study to characterize and quantify the arterial pulse wave components based on the use of logarithmic normal function (LNF). The measurements were carried out parallel from the index finger and toe tip with healthy subjects. In addition, a second derivative of the PPG signal (SNPPG) was also analyzed. The tests were applied to arterial pulse waves from 11 subjects between 5 and 69 years. The results show good correlation of pulse wave changes as a function of age.","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126259859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Suuberg, Yijun Yao, Rui Shen, Ozgur Bozkurt, K. Pennell
This paper considers the significance of observed subslab contaminant concentrations on the vapor intrusion process. In field measurements, there is observed wide variability in the ratio of indoor air contaminant concentration to subslab contaminant concentration. Here various aspects of the relationship of subslab concentrations to indoor contaminant levels are explored using a threedimensional fluid dynamics model of the process. Subslab concentrations are determined mainly by diffusional processes and they are reasonably uniform across the subslab for buildings on homogeneous soils (with no significant advective subsurface disturbance). Also, subslab concentrations do not determine the main mode of contaminant entry into a structure (advection or diffusion), and widely different contaminant entry rates can be obtained with very similar subslab concentrations, depending upon whether the soil type supports advection or not.
{"title":"Modeling vapor intrusion processes and evaluating risks using subslab data","authors":"E. Suuberg, Yijun Yao, Rui Shen, Ozgur Bozkurt, K. Pennell","doi":"10.2495/EHR110111","DOIUrl":"https://doi.org/10.2495/EHR110111","url":null,"abstract":"This paper considers the significance of observed subslab contaminant concentrations on the vapor intrusion process. In field measurements, there is observed wide variability in the ratio of indoor air contaminant concentration to subslab contaminant concentration. Here various aspects of the relationship of subslab concentrations to indoor contaminant levels are explored using a threedimensional fluid dynamics model of the process. Subslab concentrations are determined mainly by diffusional processes and they are reasonably uniform across the subslab for buildings on homogeneous soils (with no significant advective subsurface disturbance). Also, subslab concentrations do not determine the main mode of contaminant entry into a structure (advection or diffusion), and widely different contaminant entry rates can be obtained with very similar subslab concentrations, depending upon whether the soil type supports advection or not.","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122013638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
There is substantial evidence from epidemiological studies that the etiology of many ‘modern’ diseases is linked in part to environmental pollution. A number of observations suggest that an imbalance in cellular oxidants and antioxidants is a critical underlying factor. Many environmental pollutants, without being redoxactive and capable of causing oxidation in vitro, are able to shift the oxidant/antioxidant balance of the cells, thus triggering pathological responses. It is difficult to assess the biological impact of mixtures of environmental pollutants because of their complexity. We propose the parallel use of normal (parental) and genetically engineered superoxide dismutase (SOD)-deficient E. coli strains, as a tool for the detection of prooxidant-acting environmental pollutants. Doubling time, viability, mutation rate, and induction of antioxidant regulons are used as parameters to assess the pollutants’ toxicity and prooxidant action. SOD-deficient E. coli is highly sensitive to agents causing oxidative stress directly or indirectly. This sensitivity can be measured and is highly reproducible. Using E. coli is advantageous because the organism is well studied, can be stored at low temperatures for a very long time, and can be grown under standard, well-defined conditions. The parallel use of SOD-deficient mutants and SOD-proficient parents permits discrimination between compounds that exert general toxicity and compounds that act as prooxidants in vivo. The bioassay was used for fast screening of potentially hazardous chemicals with pro-oxidative action.
{"title":"Cell-based bioassay for compounds with prooxidant activity","authors":"M. Thomas, Ludmil Benov","doi":"10.2495/EHR110161","DOIUrl":"https://doi.org/10.2495/EHR110161","url":null,"abstract":"There is substantial evidence from epidemiological studies that the etiology of many ‘modern’ diseases is linked in part to environmental pollution. A number of observations suggest that an imbalance in cellular oxidants and antioxidants is a critical underlying factor. Many environmental pollutants, without being redoxactive and capable of causing oxidation in vitro, are able to shift the oxidant/antioxidant balance of the cells, thus triggering pathological responses. It is difficult to assess the biological impact of mixtures of environmental pollutants because of their complexity. We propose the parallel use of normal (parental) and genetically engineered superoxide dismutase (SOD)-deficient E. coli strains, as a tool for the detection of prooxidant-acting environmental pollutants. Doubling time, viability, mutation rate, and induction of antioxidant regulons are used as parameters to assess the pollutants’ toxicity and prooxidant action. SOD-deficient E. coli is highly sensitive to agents causing oxidative stress directly or indirectly. This sensitivity can be measured and is highly reproducible. Using E. coli is advantageous because the organism is well studied, can be stored at low temperatures for a very long time, and can be grown under standard, well-defined conditions. The parallel use of SOD-deficient mutants and SOD-proficient parents permits discrimination between compounds that exert general toxicity and compounds that act as prooxidants in vivo. The bioassay was used for fast screening of potentially hazardous chemicals with pro-oxidative action.","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126596108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Accurate rupture prediction of intracranial aneurysms is crucial because not all aneurysms rupture. With past reports that aspect ratio (AR) and size ratio (SR) have significant correlations with rupture probability, these two morphological parameters are regarded as promising for rupture prediction: an aneurysm with a higher AR or SR is more likely to rupture than one with a lower AR or SR. However, 100% reliability of prediction is not guaranteed even with these parameters. It is necessary to clarify reasons for the high correlations of AR and SR with rupture status and what is responsible for unsuccessful predictions. In this paper, the authors discuss haemodynamic significance of the two parameters with a special focus on stagnant flow and resulting thrombus formation, which are considered to play important roles in the process of aneurysmal rupture. Results with computational fluid dynamics and a platelet aggregation model are also shown in order to demonstrate that stagnant flow and thrombus formation can be observed even in an aneurysm with low AR and SR.
{"title":"Correlation of morphological parameters with likelihood of thrombus formation in intracranial aneurysms","authors":"K. Shimano, Y. Nakagawa","doi":"10.2495/EHR110271","DOIUrl":"https://doi.org/10.2495/EHR110271","url":null,"abstract":"Accurate rupture prediction of intracranial aneurysms is crucial because not all aneurysms rupture. With past reports that aspect ratio (AR) and size ratio (SR) have significant correlations with rupture probability, these two morphological parameters are regarded as promising for rupture prediction: an aneurysm with a higher AR or SR is more likely to rupture than one with a lower AR or SR. However, 100% reliability of prediction is not guaranteed even with these parameters. It is necessary to clarify reasons for the high correlations of AR and SR with rupture status and what is responsible for unsuccessful predictions. In this paper, the authors discuss haemodynamic significance of the two parameters with a special focus on stagnant flow and resulting thrombus formation, which are considered to play important roles in the process of aneurysmal rupture. Results with computational fluid dynamics and a platelet aggregation model are also shown in order to demonstrate that stagnant flow and thrombus formation can be observed even in an aneurysm with low AR and SR.","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122078825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cerebral microembolism may lead to the restriction of blood supply due to damaged blood vessel tissue (focal ischemia) which is increasingly seen as the cause of cognitive deterioration including Alzheimer’s disease and vascular dementia. The flow through fractal models of the peripheral vasculature of the Anterior Cerebral Arteries (ACA) and Middle Cerebral Arteries (MCA) was modelled. The multi-scale model of the cerebral vasculature was coupled with blood flow and embolus transport models. The model incorporated asymmetric bifurcation trees, embolus-vascular interactions and autoregulation. Simulations were carried out where the embolus deposition rate, embolus diameter and embolus introduction rate were varied. Increasing the embolus diameter and embolus introduction rate increased the number of blocked terminal arteries to a quasi steady-state. For a low embolus deposition rate the MCA and ACA territory had the same embolization dynamics, even though, the MCA was larger than the ACA. It was also found for a higher embolus deposition rate the MCA, due to its more expansive structure, was less prone to occlusion than the ACA. The results also showed the effect of a single blockage is expected to be less severe in asymmetric flow than symmetric flow. This model will assist in developing a better understanding into embolic stroke and effect of
{"title":"Modelling of embolus transport and embolic stroke","authors":"I. Sutalo, A. Bui, K. Liffman, R. Manasseh","doi":"10.2495/EHR110301","DOIUrl":"https://doi.org/10.2495/EHR110301","url":null,"abstract":"Cerebral microembolism may lead to the restriction of blood supply due to damaged blood vessel tissue (focal ischemia) which is increasingly seen as the cause of cognitive deterioration including Alzheimer’s disease and vascular dementia. The flow through fractal models of the peripheral vasculature of the Anterior Cerebral Arteries (ACA) and Middle Cerebral Arteries (MCA) was modelled. The multi-scale model of the cerebral vasculature was coupled with blood flow and embolus transport models. The model incorporated asymmetric bifurcation trees, embolus-vascular interactions and autoregulation. Simulations were carried out where the embolus deposition rate, embolus diameter and embolus introduction rate were varied. Increasing the embolus diameter and embolus introduction rate increased the number of blocked terminal arteries to a quasi steady-state. For a low embolus deposition rate the MCA and ACA territory had the same embolization dynamics, even though, the MCA was larger than the ACA. It was also found for a higher embolus deposition rate the MCA, due to its more expansive structure, was less prone to occlusion than the ACA. The results also showed the effect of a single blockage is expected to be less severe in asymmetric flow than symmetric flow. This model will assist in developing a better understanding into embolic stroke and effect of","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129314240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In drug discovery, it is very important to predict the side effect of the drug accurately. The prediction algorithm of the drug side effect is presented in this study. This algorithm is based on the concept of the structure-activity relationship. Firstly, the drug side effects are gathered from the registration of medical products by using text mining. Next, the chemical structure information of the drug is obtained from the PubChem data base. Then, the association rules between the chemical structure and the side effects are defined. The associate rules are applied to the prediction of the side effect of 10 chemical products.
{"title":"Association rule derivation for side effects of medical supplies and its application","authors":"H. Shiroyama, Y. Zuo, E. Kita","doi":"10.2495/EHR110381","DOIUrl":"https://doi.org/10.2495/EHR110381","url":null,"abstract":"In drug discovery, it is very important to predict the side effect of the drug accurately. The prediction algorithm of the drug side effect is presented in this study. This algorithm is based on the concept of the structure-activity relationship. Firstly, the drug side effects are gathered from the registration of medical products by using text mining. Next, the chemical structure information of the drug is obtained from the PubChem data base. Then, the association rules between the chemical structure and the side effects are defined. The associate rules are applied to the prediction of the side effect of 10 chemical products.","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127233109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The 2009 earthquake in Padang, the capital city of the province of West Sumatra in Indonesia, devastated the city’s physical landscape, causing material and economic damage that has yet to be repaired. Environmental health issues arising from the earthquake also remain mostly unresolved. Many of the earthquake’s most devastating effects were exacerbated by the lack of effective contingency planning and responses in place. This paper presents the events relating to reconstruction efforts in the year following the earthquake and the environmental health issues that emerged, including problems related to the water supply and a serious outbreak of dengue fever. Four features of the Indonesian political landscape that affected the response to the disaster and the reconstruction process are identified: corruption; regional autonomy; technological leapfrogging; and the concept of pembangunan [development].
{"title":"Environmental health issues in the wake of a major earthquake in West Sumatra, Indonesia.","authors":"D. Fanany","doi":"10.2495/EHR110141","DOIUrl":"https://doi.org/10.2495/EHR110141","url":null,"abstract":"The 2009 earthquake in Padang, the capital city of the province of West Sumatra in Indonesia, devastated the city’s physical landscape, causing material and economic damage that has yet to be repaired. Environmental health issues arising from the earthquake also remain mostly unresolved. Many of the earthquake’s most devastating effects were exacerbated by the lack of effective contingency planning and responses in place. This paper presents the events relating to reconstruction efforts in the year following the earthquake and the environmental health issues that emerged, including problems related to the water supply and a serious outbreak of dengue fever. Four features of the Indonesian political landscape that affected the response to the disaster and the reconstruction process are identified: corruption; regional autonomy; technological leapfrogging; and the concept of pembangunan [development].","PeriodicalId":370021,"journal":{"name":"WIT Transactions on Biomedicine and Health","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132117090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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