Evaluation of economic feasibility of a bio-gasification facility needs understanding of its unit... more Evaluation of economic feasibility of a bio-gasification facility needs understanding of its unit cost under different production capacities. The objective of this study was to evaluate the unit cost of syngas production at capacities from 60 through 1800Nm3/h using an economic model with three regression analysis techniques (simple regression, reciprocal regression, and log-log regression). The preliminary result of this study showed that reciprocal regression analysis technique had the best fit curve between per unit cost and production capacity, with sum of error squares (SES) lower than 0.001 and coefficient of determination of (R2) 0.996. The regression analysis techniques determined the minimum unit cost of syngas production for micro-scale bio-gasification facilities of $0.052/Nm3, under the capacity of 2,880 Nm3/h. The results of this study suggest that to reduce cost, facilities should run at a high production capacity. In addition, the contribution of this technique could be the new categorical criterion to evaluate micro-scale bio-gasification facility from the perspective of economic analysis.
International Journal of Kinesiology and Sports Science
Background: It is less known how the constraints placed upon public spaces and social interaction... more Background: It is less known how the constraints placed upon public spaces and social interaction have impacted college students’ motivation to be physically active. Objective: This study examined, first, the changes in college students’ body mass index (BMI), physical activity (PA), and self-determined motivation before and during the COVID-19 third-wave lockdown and, second, the role of moderate-to-vigorous PA (MVPA) and self-determined motivation on BMI during the lockdown. Method: This study was a longitudinal prospective study with two data collection phases. A sample of 104 college students (69 females, 35 males, Mage = 18.19[1.5]) completing both pre- and posttest data turned in self-report data on BMI, PA (vigorous PA - VPA, moderate PA - MPA), MVPA, and self-determined motivation. Results: The results showed a statistically significant increase in participants’ BMI (t[79] = 4.70[2.98], p =.001, d =.11) but no statistically significant changes in PA. The findings demonstrate...
IMPORTANCE Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2... more IMPORTANCE Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely underestimates the true prevalence of infections. Large-scale seroprevalence surveys can better estimate infection across many geographic regions. OBJECTIVE To estimate the prevalence of persons with SARS-CoV-2 antibodies using residual sera from commercial laboratories across the US and assess changes over time. DESIGN, SETTING, AND PARTICIPANTS This repeated, cross-sectional study conducted across all 50 states, the District of Columbia, and Puerto Rico used a convenience sample of residual serum specimens provided by persons of all ages that were originally submitted for routine screening or clinical management from 2 private clinical commercial laboratories. Samples were obtained during 4 collection periods
Cancer Epidemiology, Biomarkers & Prevention, 2019
Background: The Population Health Assessment initiative by NCI sought to enhance cancer centers’ ... more Background: The Population Health Assessment initiative by NCI sought to enhance cancer centers’ capacity to acquire, aggregate, and integrate data from multiple sources, as well as to plan, coordinate, and enhance catchment area analysis activities. Methods: Key objectives of this initiative are pooling data and comparing local data with national data. A novel aspect of analyzing data from this initiative is the methodology used to weight datasets from sites that collected both probability and nonprobability samples. This article describes the methods developed to weight data, which cancer centers collected with combinations of probability, and nonprobability sampling designs. Results: We compare alternative weighting methods in particular for the hybrid probability and nonprobability sampling designs employed by different cancer centers. We also include comparisons of local center data with national survey data from large probability samples. Conclusions: This hybrid approach to c...
Since bio-gasification is a potentially more efficient way to utilize bio-energy, the economic fe... more Since bio-gasification is a potentially more efficient way to utilize bio-energy, the economic feasibility becomes one of the greatest issues when we apply this new technology. Evaluation of economic feasibility of a bio-gasification facility needs understanding of its production unit cost under different capacities and different working shift modes. The objectives of this study were to evaluate the unit cost of bio-syngas and bio-fuel products at different capacities by using economic modeling method. Result showed that economic feasibility of a power facility was significantly affected by its production capacity and operating mode (one shift, two shifts, or three shifts mode). Economic feasibility could be improved by increasing production capacity or by changing operating mode to two or three shifts from one shift. The economic evaluation model and cost analysis software developed in this study could be a good tool for economic analysis of bio-syngasand bio-fuel products from biomass gasification.
Background and Aims: The recent COVID-19 pandemic has upended health care delivery in the United ... more Background and Aims: The recent COVID-19 pandemic has upended health care delivery in the United States and the world, resulting in a rapid switch from in-person patient interactions to telemedicine. While telemedicine evaluation offers many advantages including convenience, patient satisfaction and improved access, it is unclear if it is an adequate substitute for in-person evaluation for complex interventions such as liver transplantation. There is a dearth of multi-center data on transplant evaluation using telemedicine and its impact on liver transplant outcomes. Methods: We performed a retrospective analysis of 1,118 non-local patients who underwent non-urgent evaluation for liver transplantation within the Veterans Affairs Health care system, which had implemented liver transplant evaluation by telemedicine predating COVID-19. During the study period, 176 patients underwent initial evaluation by telemedicine and 942, by an in-person evaluation. We studied the association of evaluation by telemedicine on pre-transplant mortality, as well as with time to evaluation, listing and transplantation. Results: After its initial introduction, the proportion of patients who underwent transplant evaluation by telemedicine, increased from 1.6% in 2013 to 20.2% in 2017. The percentage of telemedicine adoption varied across centers, from 0.5% to 44.2% of all evaluations. Patients in the telemedicine group had a shorter unadjusted time from referral to evaluation (20.0 vs. 27.0 days, p<0.0001), and listing (65.0 vs. 99.0 days, p<0.0001). There were no differences in time from referral to transplantation (220.5 vs. 265.5 days, p=0.25). These differences were maintained on an adjusted analysis, with transplant evaluation by telemedicine associated with a shorter adjusted time from referral to evaluation (19.4 vs. 28.9 days, p<0.001), and listing (97.4 vs. 118.7 days, p=0.0003), but not to transplantation (253.3 vs. 311.2 days, p=0.06). Telemedicine offered the highest benefit in patients with MELD below 20. Conclusion: In a national multi-center study within the VA system, Liver transplant evaluation by telemedicine is associated with a shorter time to evaluation and listing, and a trend towards shorter time to transplantation. (Table presented.) Time from referral to evaluation, listing and transplantation, by telemedicne or in-person evaluation (Generalized linear regression) by MELD-Na
Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive ou... more Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive outcomes along the HIV care continuum. However, access to HIV-experienced clinicians may be limited, particularly in nonmetropolitan areas, where HIV is increasing. We examined HIV clinician workforce capacity, focusing on HIV experience and urban–rural differences, in the Southern United States. Methods We used Medicaid claims and clinician characteristics (Medicaid Analytic eXtract [MAX] and MAX Provider Characteristics, 2009–2011), county-level rurality (National Center for Health Statistics, 2013), and diagnosed HIV cases (AIDSVu, 2014) to assess HIV clinician capacity in 14 states. We assumed that clinicians accepting Medicaid approximated the region’s HIV workforce, since three-quarters of clinicians accept Medicaid insurance. HIV-experienced clinicians were defined as those providing care to ≥ 10 Medicaid enrollees over 3 years. We assessed HIV workforce capacity with county-level c...
Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive ou... more Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive outcomes along the HIV care continuum. However, access to HIV-experienced clinicians may be limited, particularly in nonmetropolitan areas, where HIV is increasing. We examined HIV clinician workforce capacity, focusing on HIV experience and urban–rural differences, in the Southern United States. Methods We used Medicaid claims and clinician characteristics (Medicaid Analytic eXtract [MAX] and MAX Provider Characteristics, 2009–2011), county-level rurality (National Center for Health Statistics, 2013), and diagnosed HIV cases (AIDSVu, 2014) to assess HIV clinician capacity in 14 states. We assumed that clinicians accepting Medicaid approximated the region’s HIV workforce, since three-quarters of clinicians accept Medicaid insurance. HIV-experienced clinicians were defined as those providing care to ≥ 10 Medicaid enrollees over 3 years. We assessed HIV workforce capacity with county-level c...
Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.... more Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy. The economic feasibility becomes one of the greatest issues when we apply this new technology. Evaluation of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift modes. The objective of this study was to evaluate the unit cost of biofuel products (Liquid HCs, Light HCs and Oxygenates C x H y O z) under different capacities using a modeling method. The cost analysis model was developed using Visual Basic Microsoft 2008, computer programming language and mathematical equations. The modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of facilities. As the facility capacity increased from 65 to 10,000 N m 3 h À1 , the biofuel production unit cost of gas (Light HCs), oil (Liquid HCs), and aqueous (Oxygenates C x H y O z
The objectives of this study were to evaluate the return of investment and profitability of a bio... more The objectives of this study were to evaluate the return of investment and profitability of a bio-gasification facility using a modeling method. Based on preliminary market analysis, the results determined that the power facilities driven by biomass gasifiers could be profitable if they consider the most sensitive cost factors such as labor, project investment, and feedstock supply. The result showed that economic feasibility of bio-gasification facility can significantly affect by its production capacity and operating modes (one shift, two shifts, or three shifts). The cost analysis modeling approach developed in this study could be a good approach for economic analysis of bio-syngas and bio-fuel products. In addition, this study demonstrated a unique modeling approach to analyze return of investment and profitability of biofuels production.
Evaluation of economic feasibility of a bio-gasification facility needs understanding of its unit... more Evaluation of economic feasibility of a bio-gasification facility needs understanding of its unit cost under different production capacities. The objective of this study was to evaluate the unit cost of syngas production at capacities from 60 through 1800Nm3/h using an economic model with three regression analysis techniques (simple regression, reciprocal regression, and log-log regression). The preliminary result of this study showed that reciprocal regression analysis technique had the best fit curve between per unit cost and production capacity, with sum of error squares (SES) lower than 0.001 and coefficient of determination of (R2) 0.996. The regression analysis techniques determined the minimum unit cost of syngas production for micro-scale bio-gasification facilities of $0.052/Nm3, under the capacity of 2,880 Nm3/h. The results of this study suggest that to reduce cost, facilities should run at a high production capacity. In addition, the contribution of this technique could be the new categorical criterion to evaluate micro-scale bio-gasification facility from the perspective of economic analysis.
International Journal of Kinesiology and Sports Science
Background: It is less known how the constraints placed upon public spaces and social interaction... more Background: It is less known how the constraints placed upon public spaces and social interaction have impacted college students’ motivation to be physically active. Objective: This study examined, first, the changes in college students’ body mass index (BMI), physical activity (PA), and self-determined motivation before and during the COVID-19 third-wave lockdown and, second, the role of moderate-to-vigorous PA (MVPA) and self-determined motivation on BMI during the lockdown. Method: This study was a longitudinal prospective study with two data collection phases. A sample of 104 college students (69 females, 35 males, Mage = 18.19[1.5]) completing both pre- and posttest data turned in self-report data on BMI, PA (vigorous PA - VPA, moderate PA - MPA), MVPA, and self-determined motivation. Results: The results showed a statistically significant increase in participants’ BMI (t[79] = 4.70[2.98], p =.001, d =.11) but no statistically significant changes in PA. The findings demonstrate...
IMPORTANCE Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2... more IMPORTANCE Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely underestimates the true prevalence of infections. Large-scale seroprevalence surveys can better estimate infection across many geographic regions. OBJECTIVE To estimate the prevalence of persons with SARS-CoV-2 antibodies using residual sera from commercial laboratories across the US and assess changes over time. DESIGN, SETTING, AND PARTICIPANTS This repeated, cross-sectional study conducted across all 50 states, the District of Columbia, and Puerto Rico used a convenience sample of residual serum specimens provided by persons of all ages that were originally submitted for routine screening or clinical management from 2 private clinical commercial laboratories. Samples were obtained during 4 collection periods
Cancer Epidemiology, Biomarkers & Prevention, 2019
Background: The Population Health Assessment initiative by NCI sought to enhance cancer centers’ ... more Background: The Population Health Assessment initiative by NCI sought to enhance cancer centers’ capacity to acquire, aggregate, and integrate data from multiple sources, as well as to plan, coordinate, and enhance catchment area analysis activities. Methods: Key objectives of this initiative are pooling data and comparing local data with national data. A novel aspect of analyzing data from this initiative is the methodology used to weight datasets from sites that collected both probability and nonprobability samples. This article describes the methods developed to weight data, which cancer centers collected with combinations of probability, and nonprobability sampling designs. Results: We compare alternative weighting methods in particular for the hybrid probability and nonprobability sampling designs employed by different cancer centers. We also include comparisons of local center data with national survey data from large probability samples. Conclusions: This hybrid approach to c...
Since bio-gasification is a potentially more efficient way to utilize bio-energy, the economic fe... more Since bio-gasification is a potentially more efficient way to utilize bio-energy, the economic feasibility becomes one of the greatest issues when we apply this new technology. Evaluation of economic feasibility of a bio-gasification facility needs understanding of its production unit cost under different capacities and different working shift modes. The objectives of this study were to evaluate the unit cost of bio-syngas and bio-fuel products at different capacities by using economic modeling method. Result showed that economic feasibility of a power facility was significantly affected by its production capacity and operating mode (one shift, two shifts, or three shifts mode). Economic feasibility could be improved by increasing production capacity or by changing operating mode to two or three shifts from one shift. The economic evaluation model and cost analysis software developed in this study could be a good tool for economic analysis of bio-syngasand bio-fuel products from biomass gasification.
Background and Aims: The recent COVID-19 pandemic has upended health care delivery in the United ... more Background and Aims: The recent COVID-19 pandemic has upended health care delivery in the United States and the world, resulting in a rapid switch from in-person patient interactions to telemedicine. While telemedicine evaluation offers many advantages including convenience, patient satisfaction and improved access, it is unclear if it is an adequate substitute for in-person evaluation for complex interventions such as liver transplantation. There is a dearth of multi-center data on transplant evaluation using telemedicine and its impact on liver transplant outcomes. Methods: We performed a retrospective analysis of 1,118 non-local patients who underwent non-urgent evaluation for liver transplantation within the Veterans Affairs Health care system, which had implemented liver transplant evaluation by telemedicine predating COVID-19. During the study period, 176 patients underwent initial evaluation by telemedicine and 942, by an in-person evaluation. We studied the association of evaluation by telemedicine on pre-transplant mortality, as well as with time to evaluation, listing and transplantation. Results: After its initial introduction, the proportion of patients who underwent transplant evaluation by telemedicine, increased from 1.6% in 2013 to 20.2% in 2017. The percentage of telemedicine adoption varied across centers, from 0.5% to 44.2% of all evaluations. Patients in the telemedicine group had a shorter unadjusted time from referral to evaluation (20.0 vs. 27.0 days, p<0.0001), and listing (65.0 vs. 99.0 days, p<0.0001). There were no differences in time from referral to transplantation (220.5 vs. 265.5 days, p=0.25). These differences were maintained on an adjusted analysis, with transplant evaluation by telemedicine associated with a shorter adjusted time from referral to evaluation (19.4 vs. 28.9 days, p<0.001), and listing (97.4 vs. 118.7 days, p=0.0003), but not to transplantation (253.3 vs. 311.2 days, p=0.06). Telemedicine offered the highest benefit in patients with MELD below 20. Conclusion: In a national multi-center study within the VA system, Liver transplant evaluation by telemedicine is associated with a shorter time to evaluation and listing, and a trend towards shorter time to transplantation. (Table presented.) Time from referral to evaluation, listing and transplantation, by telemedicne or in-person evaluation (Generalized linear regression) by MELD-Na
Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive ou... more Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive outcomes along the HIV care continuum. However, access to HIV-experienced clinicians may be limited, particularly in nonmetropolitan areas, where HIV is increasing. We examined HIV clinician workforce capacity, focusing on HIV experience and urban–rural differences, in the Southern United States. Methods We used Medicaid claims and clinician characteristics (Medicaid Analytic eXtract [MAX] and MAX Provider Characteristics, 2009–2011), county-level rurality (National Center for Health Statistics, 2013), and diagnosed HIV cases (AIDSVu, 2014) to assess HIV clinician capacity in 14 states. We assumed that clinicians accepting Medicaid approximated the region’s HIV workforce, since three-quarters of clinicians accept Medicaid insurance. HIV-experienced clinicians were defined as those providing care to ≥ 10 Medicaid enrollees over 3 years. We assessed HIV workforce capacity with county-level c...
Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive ou... more Background Human immunodeficiency virus (HIV)–experienced clinicians are critical for positive outcomes along the HIV care continuum. However, access to HIV-experienced clinicians may be limited, particularly in nonmetropolitan areas, where HIV is increasing. We examined HIV clinician workforce capacity, focusing on HIV experience and urban–rural differences, in the Southern United States. Methods We used Medicaid claims and clinician characteristics (Medicaid Analytic eXtract [MAX] and MAX Provider Characteristics, 2009–2011), county-level rurality (National Center for Health Statistics, 2013), and diagnosed HIV cases (AIDSVu, 2014) to assess HIV clinician capacity in 14 states. We assumed that clinicians accepting Medicaid approximated the region’s HIV workforce, since three-quarters of clinicians accept Medicaid insurance. HIV-experienced clinicians were defined as those providing care to ≥ 10 Medicaid enrollees over 3 years. We assessed HIV workforce capacity with county-level c...
Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy.... more Bio-gasification is a new technology and considered as a more efficient way to utilize bioenergy. The economic feasibility becomes one of the greatest issues when we apply this new technology. Evaluation of economic feasibility of a bio-gasification facility needs better understanding of its production unit cost under different capacities and different working shift modes. The objective of this study was to evaluate the unit cost of biofuel products (Liquid HCs, Light HCs and Oxygenates C x H y O z) under different capacities using a modeling method. The cost analysis model was developed using Visual Basic Microsoft 2008, computer programming language and mathematical equations. The modeling results showed that the unit costs of biofuel product from bio-gasification facility were significantly affected by production capacities of facilities. As the facility capacity increased from 65 to 10,000 N m 3 h À1 , the biofuel production unit cost of gas (Light HCs), oil (Liquid HCs), and aqueous (Oxygenates C x H y O z
The objectives of this study were to evaluate the return of investment and profitability of a bio... more The objectives of this study were to evaluate the return of investment and profitability of a bio-gasification facility using a modeling method. Based on preliminary market analysis, the results determined that the power facilities driven by biomass gasifiers could be profitable if they consider the most sensitive cost factors such as labor, project investment, and feedstock supply. The result showed that economic feasibility of bio-gasification facility can significantly affect by its production capacity and operating modes (one shift, two shifts, or three shifts). The cost analysis modeling approach developed in this study could be a good approach for economic analysis of bio-syngas and bio-fuel products. In addition, this study demonstrated a unique modeling approach to analyze return of investment and profitability of biofuels production.
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