CO2 emission hotspots analysis on supply chains for wooden houses in Japan

Ninety-four percent of CO2 emissions induced by final demand in the global construction sector stem from the supply chain. Therefore, it is necessary to identify the CO2 emission hotspots within the supply chain and implement targeted reduction measures. This study proposed a supply chain clustering approach considering the functional unit of houses and identified CO2 emission hotspots within the supply chain structure of wooden houses, which accounted for approximately 90% of the total housing stock in Japan. We founded that the top ten CO2 emission clusters (i.e., emission hotspots) account for approximately 40% of the carbon footprint (38 t-CO2) of a wooden house. Specifically, the iron and steel cluster, which includes the pig iron and crude steel sectors, and the cement cluster, comprising the cement and ready-mixed concrete sectors, collectively contribute to approximately 75% of the CO2 emissions within the top 10 clusters. Therefore, the reduction of CO2 emissions from these clusters is of paramount importance. Decision-makers should promote renovation and remodeling policies for vacant houses and prioritize the reuse of foundations, predominantly constructed using steel and cement products, to reduce the supply-chain emissions from wooden houses.

Reduction of life-cycle CO2 emissions by expanding car-sharing services: A case study on Japan

Carbon neutrality is a growing concern for all global economies. We considered the number of new and used cars registered during 2009-2018 in Japan and estimated the total number of private and shared cars, assuming that when owners abandoned their old cars, a certain percentage of the owners chose to use a car-sharing service (i.e., car rental service), instead of buying a new private car. We estimated the CO2 emissions generated during the manufacturing, driving, and disposal stages of cars, to analyze the impact of car sharing on CO2 emissions. Then, we determined the changes in the life-cycle CO2 emissions of all the cars for three car-sharing penetration rates (0, 5, and 100%), assuming that all the cars were gasoline-powered. Additionally, we analyzed how electric vehicles can optimize the proposed strategy. An increase in car-sharing services significantly reduced vehicular CO2 emissions; the decrease in CO2 emissions from private cars when owners switched to car services significantly exceeded the increase in the CO2 emissions associated with the increased number of cars. The proposed model can serve as a reliable framework to analyze the current status of CO2 emissions and simulate the future changes in car-sharing services.

Production efficiency and cost reduction potential of biodiesel fuel plants using waste cooking oil in Japan

Biodiesel fuel (BDF) is a potentially carbon-neutral fuel that could play a potentially important role in preventing global warming. However, its high production cost poses a challenge for many BDF producers. To establish an efficient method for BDF production and increase its cost competitiveness, the production efficiencies of 35 BDF plants in Japan, which produce BDF from waste cooking oil, were evaluated. Moreover, the cost reduction potential associated with improved efficiency was estimated. The empirical analysis revealed that (1) approximately 92% of the BDF plants have inefficient production; (2) they exhibit two predominant types of inefficiencies, technical and scale inefficiencies, and (3) improvement of production inefficiency can lead to an average production cost reduction of 3.52 yen per liter of BDF. To increase the production efficiency, it is important to improve the quality of the waste cooking oil used and increase the production scale. It is recommended that operators of inefficient BDF plants learn the production activities of the most efficient plants identified in this study. Furthermore, government policies focused on efficient BDF plants are essential to increase BDF production with limited resources.

Determinants of technical inefficiency in China's coal-fired power plants and policy recommendations for CO2 mitigation

This study applies data envelopment analysis (DEA) to estimate the technical efficiency (TE) and CO₂ emission reduction potential of 1270 coal-fired power plants in 28 Chinese provinces and municipalities. The large dataset used in the study includes 727 combined heat and power (CHP) plants and 543 thermal power plants. Results show an average TE score of 0.57 for the CHP power plants and 0.58 for the thermal power plants, suggesting a significant potential to reduce coal consumption in both types of coal-fired plants. Total CO₂ emission reduction potential was estimated to be 953 Mt-CO₂, or 19% of the total CO₂ emissions of China's electricity and heat producing sectors, indicating that China's coal-fired power plants have a significant potential to mitigate CO₂ emissions through technological improvement. In the second stage of the study, a Tobit regression analysis was conducted to identify the determinants of TE. Factors such as the plant's annual operation rate and capacity utilization rate were found to be significant influences. Based on our results, we propose that the Chinese government create a power distribution structure that generates electricity using technologically efficient equipment in areas rich in coal resources and distributes the generated electricity to other areas of the country.

Critical supply chains for mitigating PM2.5 emission-related mortalities in India

Air pollution and its health-related effects are a major concern globally, and many people die from air pollution-related diseases each year. This study employed a structural path analysis combined with a health impact inventory database analysis to estimate the number of consumption-based PM_2.5 emission-related deaths attributed to India's power supply sector. We identified critical supply chain paths for direct (production) electricity use and indirect (consumption) use. We also considered both domestic and foreign final demand and its effect on PM_2.5 emission-related deaths. Several conclusions could be drawn from our results. First, the effect of indirect electricity usage on PM_2.5 emission-related deaths is approximately four times larger than that for direct usage. Second, a large percentage of pollution-related deaths can be attributed to India's domestic final demand usage; however, electricity usage in the intermediate and final demand sectors is inextricably linked. Third, foreign final demand sectors from the Middle East, the USA, and China contribute indirectly toward PM_2.5 emission-related deaths, specifically in the rice export supply chain. The results show that the Indian government should implement urgent measures to curb electricity use in rice supply chains in order to reduce the number of PM_2.5 emission-related deaths.

Driving propensity and vehicle lifetime mileage: A quantile regression approach

This study aims to determine the relationship between motor vehicle lifetime and lifetime mileage, while considering drivers' propensity to drive and its effects on vehicle CO₂ emissions. To do this, we analyze the relationship between lifetime mileage and vehicle lifetime for two vehicle types; a hybrid and a gasoline vehicle. We also employ a quantile regression approach to estimate the effects of drivers' propensity to drive on lifetime mileage. By estimating the CO₂ emissions based on driver's propensity to drive, we analyze the effects of propensity to drive on vehicle CO₂ emissions. Our results show that, for drivers who drive longer distances, the rate of decrease in average mileage grows as the vehicle age increases. Further, the results of our analysis, which considers this decrease in mileage, show that the cumulative CO₂ emissions calculated under the assumption of uniform average annual mileage have been overestimated. The actual lifecycle CO₂ emissions for the Prius are therefore smaller than previously reported by the previous studies, leading us to conclude that the hybrid is a more environmentally friendly vehicle than previously thought. Those of the Premio as a conventional gasoline vehicle, however, is approximately twice that. We suggest that vehicle lifecycle assessments should take into account the annual decrease in mileage demonstrated in this study.

Supply Constraint from Earthquakes in Japan in Input-Output Analysis

Disasters often cause exogenous flow damage (i.e., the [hypothetical] difference in economic scale with and without a disaster in a certain period) to production ("supply constraint"). However, input-output (IO) analysis (IOA) cannot usually consider it, because the Leontief quantity model (LQM) assumes that production is endogenous; the Ghosh quantity model (GQM) is considered implausible; and the Leontief price model (LPM) and the Ghosh price model (GPM) assume that quantity is fixed. This study proposes to consider a supply constraint in the LPM, introducing the price elasticity of demand. This study uses the loss of social surplus (SS) as a damage estimation because production (sales) is less informative as a damage index than profit (margin); that is, production can be any amount if without considering profit, and it does not tell exactly how much profit is lost for each supplier (upstream sector) and buyer (downstream sector). As a model application, this study examines Japan's largest five earthquakes from 1995 to 2017 and the Great East Japan Earthquake (GEJE) in March 2011. The worst earthquake at the peak tends to increase price by 10-20% and decrease SS by 20-30%, when compared with the initial month's prices/production. The worst damage tends to last eight months at most, accumulating 0.5-month-production damage (i.e., the sum of [hypothetical] differences in SS with and without an earthquake [for eight months] is 50% of the initial month production). Meanwhile, the GEJE in the five prefectures had cumulatively, a 25-month-production damage until the temporal recovery at the 37th month.

Affluent countries inflict inequitable mortality and economic loss on Asia via PM2.5 emissions

This research sets out to quantify the mortality and economic loss in individual Asian countries caused by the PM_2.5 emissions induced by the consumption of the world's five highest-consuming countries (US, China, Japan, Germany, UK). In 2010 alone, the economic impact of these five countries' consumption caused a loss of almost 45 billion US dollars due to the premature deaths of more than 1 million people in Asia, including 15 thousand children younger than 5 years old. The percentage ratio of economic loss to value-added driven by consumers via trade differed greatly among the impacted countries. For the US, the highest percentage loss was 4.1% in Laos, followed by 2.0% in Bangladesh, both markedly higher than the figures for the more developed countries, such as 0.21% for Japan and 0.18% for Korea. This reflects the inequitable value chain existing between consumer countries and impacted countries, and implies that developing countries are obtaining value-added in exchange for unintentionally increased health risks, delaying their development and potentially creating a vicious circle that hinders much-needed improvements in areas like poverty reduction and public health. This inequitable situation needs to be redressed through introduction of clean energy and other types of technological assistance to help achieve United Nations Sustainable Development Goals 7, 10 and 13. Such as move is essential if premature infant deaths are to be curtailed.

Impacts of productive efficiency improvement in the global metal industry on CO2 emissions

This study focused on 14 metal sectors of the 40 countries that are the largest CO₂ emitters and developed a new analysis framework to estimate CO₂ reduction potentials based on the Greenhouse Gas Protocol through efficiency improvement of the inefficient metal sector of these countries. The analysis framework was developed by combining a multi-regional input-output database with data envelopment analysis. We found that there were 20 inefficient countries in the basic iron and steel sector, which is the largest CO₂ emitter among 14 metal sectors, and their efficiency improvements can contribute to reducing CO₂ emissions by 354 Mt, accounting for 1.4% of the global CO₂ emissions. We further proposed efficiency improvement schemes targeting the inefficient countries in order to help those countries to effectively reduce CO₂ emissions according to their sectoral and national characteristics.

Role of vehicle inspection policy in climate mitigation: The case of Japan

In 1951, the Japanese government introduced a vehicle safety inspection system and this system has an effect of shortening the 'economic' lifetimes of automobiles and increasing CO₂ emissions associated with vehicle life-cycle. This study develops an integrated assessment framework by combining dynamic discrete choice analysis with life-cycle environmental accounting analysis based on a dynamic stock model. From the empirical results, we found that (1) the economic lifetime of a Prius in the benchmark model is surprisingly short, 5.07 years, due to the strict car inspection system, and this replacement cycle has contributed to increasing CO₂ over time; and (2) abolishing car inspections at the third and fifth years would considerably contribute to reducing life-cycle CO₂ emissions associated with Prius sold during the study period, 1997 to 2016, accounting for approximately one million tons-CO₂ eq. over 20 years. Thus, we conclude that modifying the regulation policy with a focus on the car inspection system to induce car owners to keep their automobiles longer would have environmental benefits.

Progressive Cortical Neuronal Damage and Extracranial-Intracranial Bypass Surgery in Patients with Misery Perfusion

BACKGROUND AND PURPOSE

Misery perfusion may cause selective neuronal damage in atherosclerotic ICA or MCA disease. Bypass surgery can improve misery perfusion and may prevent neuronal damage. On the other hand, surgery conveys a risk for neuronal damage. The purpose of this retrospective study was to determine whether progression of cortical neuronal damage in surgically treated patients with misery perfusion is larger than that in surgically treated patients without misery perfusion or medically treated patients with misery perfusion.

MATERIALS AND METHODS

We evaluated the distribution of benzodiazepine receptors twice by using PET and ¹¹C-labeled flumazenil in 18 surgically treated patients with atherosclerotic ICA or MCA disease (9 with misery perfusion and 9 without) and no perioperative stroke before and after bypass surgery; in 8 medically treated patients with misery perfusion and no intervening ischemic event; and in 7 healthy controls. We quantified abnormal decreases in the benzodiazepine receptors of the cerebral cortex within the MCA distribution and compared changes in the benzodiazepine receptor index among the 3 groups.

RESULTS

The change in the benzodiazepine receptor index in surgically treated patients with misery perfusion (27.5 ± 15.6) during 7 ± 5 months was significantly larger than that in surgically treated patients without misery perfusion (-5.2 ± 9.4) during 6 ± 4 months (P < .001) and in medically treated patients with misery perfusion (3.2 ± 15.4) during 16 ± 6 months (P < .01).

CONCLUSIONS

Progression of cortical neuronal damage in surgically treated patients with misery perfusion and no perioperative stroke may occur and may be larger than that in medically treated patients with misery perfusion and no intervening ischemic event.

OBP-401-GFP telomerase-dependent adenovirus illuminates and kills high-metastatic more effectively than low-metastatic triple-negative breast cancer in vitro

We previously described the development of a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of MDA-MB-231 human breast cancer in nude mice. The isolated variant is highly invasive in the mammary gland and metastasized to lymph nodes in 10 of 12 mice compared with 2 of 12 of the parental cell line. OBP-401 is a telomerase-dependent cancer-specific, green fluorescent protein (GFP)-expressing adenovirus. OBP-401 was used to infect parental MDA-MB-231P cells and high-metastatic MDA-MB-231H and MDA-MB-231HLN isolated from a lymph node metastasis and MDA-MB-231HLM isolated from a lung metastasis. Time-course imaging showed that OBP-401 labeled MDA-MB-231HP, MDA-MB-231HLN, and MDA-MB-231HLM cells more brightly than MDA-MB-231 parental cells. OBP-401 killed MDA-MB-231H, MDA-MB-231HLN, and MDA-MB-231HLM cells more efficiently than MDA-MB-231P parental cells. These results indicate that OBP-401 could infect, label and then kill high-metastatic MDA-MB-231 more efficiently than low-metastatic MDA-MB-231.

Global mining risk footprint of critical metals necessary for low-carbon technologies: the case of neodymium, cobalt, and platinum in Japan

Meeting the 2-degree global warming target requires wide adoption of low-carbon energy technologies. Many such technologies rely on the use of precious metals, however, increasing the dependence of national economies on these resources. Among such metals, those with supply security concerns are referred to as critical metals. Using the Policy Potential Index developed by the Fraser Institute, this study developed a new footprint indicator, the mining risk footprint (MRF), to quantify the mining risk directly and indirectly affecting a national economy through its consumption of critical metals. We formulated the MRF as a product of the material footprint (MF) of the consuming country and the mining risks of the countries where the materials are mined. A case study was conducted for the 2005 Japanese economy to determine the MF and MRF for three critical metals essential for emerging energy technologies: neodymium, cobalt and platinum. The results indicate that in 2005 the MFs generated by Japanese domestic final demand, that is, the consumption-based metal output of Japan, were 1.0 × 10(3) t for neodymium, 9.4 × 10(3) t for cobalt, and 2.1 × 10 t for platinum. Export demand contributes most to the MF, accounting for 3.0 × 10(3) t, 1.3 × 10(5) t, and 3.1 × 10 t, respectively. The MRFs of Japanese total final demand (domestic plus export) were calculated to be 1.7 × 10 points for neodymium, 4.5 × 10(-2) points for cobalt, and 5.6 points for platinum, implying that the Japanese economy is incurring a high mining risk through its use of neodymium. This country's MRFs are all dominated by export demand. The paper concludes by discussing the policy implications and future research directions for measuring the MFs and MRFs of critical metals. For countries poorly endowed with mineral resources, adopting low-carbon energy technologies may imply a shifting of risk from carbon resources to other natural resources, in particular critical metals, and a trade-off between increased mining risk and deployment of such technologies. Our analysis constitutes a first step toward quantifying and managing the risks associated with natural resource mining.

MaTrace: tracing the fate of materials over time and across products in open-loop recycling

Even for metals, open-loop recycling is more common than closed-loop recycling due, among other factors, to the degradation of quality in the end-of-life (EoL) phase. Open-loop recycling is subject to loss of functionality of original materials, dissipation in forms that are difficult to recover, and recovered metals might need dilution with primary metals to meet quality requirements. Sustainable management of metal resources calls for the minimization of these losses. Imperative to this is quantitative tracking of the fate of materials across different stages, products, and losses. A new input-output analysis (IO) based model of dynamic material flow analysis (MFA) is presented that can trace the fate of materials over time and across products in open-loop recycling taking explicit consideration of losses and the quality of scrap into account. Application to car steel recovered from EoL vehicles (ELV) showed that after 50 years around 80% of the steel is used in products, mostly buildings and civil engineering (infrastructure), with the rest mostly resided in unrecovered obsolete infrastructure and refinery losses. Sensitivity analysis was conducted to evaluate the effects of changes in product lifespan, and the quality of scrap.