Uncovering Availability of the Secondary Iron Resources in China: Integrating Material Flow Analysis and Secondary Resources Reserve Assessment.

As the largest iron and steel producer, China still cannot meet its demand of iron and steel only through domestic primary supply in the last few decades. Hence, secondary iron resources are increasingly significant in meeting China's iron supply and demand balance. However, the secondary iron resource availability in China and how it impacts the future supply demand balance were still insufficiently discussed. In this work, we developed a material flow analysis and secondary resources reserve assessment (MFA-SRRA) integrated model, assessed secondary iron resources availability, and conducted a supply demand analysis through nine scenarios for irons in China. The results showed that China's secondary iron reserves will increase from 8.9 Gt in 2021 to 14.04 to 19.01 Gt in 2050. With the increasing secondary iron supply, more than 60% of iron ore as a source of steelmaking can be replaced by 2050. Landfills, as a significant reserve of iron but always ignored, will accumulate 1.42-1.51 Gt secondary iron resources by 2050 and should be noticed to be mined and utilized in the future. Last, we suggest that promoting innovation in landfill mining technology and making sustainable material management policies are urgent to prevent these secondary iron resources from becoming real waste.

Changes in oxygen supply-demand balance during induction of general anesthesia: an exploratory study using remimazolam.

PURPOSE: This study was performed to evaluate the changes in oxygen supply-demand balance during induction of general anesthesia using an indirect calorimeter capable of measuring oxygen consumption (VO2) and carbon dioxide production (VCO2). METHODS: This study included patients scheduled for surgery in whom remimazolam was administered as a general anesthetic. VO2 and VCO2 were measured at different intervals: upon awakening (T1), 15 min after tracheal intubation (T2), and 1 h after T2 (T3). Oxygen delivery (DO2) was calculated simultaneously with these measurements. VO2 was ascertained using an indirect calorimeter and further calculated using vital signs, among other factors. DO2 was derived from cardiac output and arterial blood gas analysis performed with an arterial pressure-based cardiac output measurement system. RESULTS: VO2, VCO2, and DO2 decreased significantly from T1 to T2 and T3 [VO2/body surface area (BSA) (ml/min/m2): T1, 130 (122-146); T2, 107 (83-139); T3, 97 (93-121); p = 0.011], [VCO2/BSA (ml/min/m2): T1, 115 (105-129); T2, 90 (71-107); T3, 81 (69-101); p = 0.011], [DO2/BSA (ml/min/m2): T1, 467 (395-582); T2, 347 (286-392); T3, 382 (238-414); p = 0.0020]. Among the study subjects, a subset exhibited minimal reduction in VCO2. Although the respiratory frequency was titrated on the basis of end-tidal CO2 levels, there was no significant difference between the groups. CONCLUSION: General anesthetic induction with remimazolam decreased VO2, VCO2, and DO2.

Managing the supply-demand mismatches and potential flows of ecosystem services from the perspective of regional integration: A case study of Hangzhou, China.

Regional integration is a development strategy that synergizes various components as a whole to maximize overall benefits. The natural heterogeneity and fluidity of ecosystem service (ES) make it a promising target for regional integration. However, the current focus on regional integration was more on the socio-economic factors rather than ecological resources, and the understanding of the supply-demand relationship and potential flow of ecosystem services was still limited. Therefore, we attempted to interpret ecological integration management by linking ES budgets, bundles, and flows in this study. The results showed that the spatial mismatches of ESs supply-demand were observed in all six selected ES types. Most of the ESs deficit regions were concentrated in urban centers, while ES surplus regions were scattered in surrounding rural areas. Multiple heterogeneous ES resources could ideally benefit an additional 0.13-4.84 million people in 9-70 townships through potential ES flows under ecological integration management. Therefore, we connected the service provisioning areas (SPAs) and service beneficiary areas (SBAs) with three types of ES flows and drew the potential provider-beneficiary relationship networks at the townships/bundles scale, demonstrating the interactive relationship of ecological integration within the region. On this basis, we also proposed the applicability matrix of governance tools for the first time according to the type of ES flows, and then put forward the corresponding governance opinions around the two aspects of "improving ES budges within clusters" and "strengthening ES flow among clusters". This study provided an ecological perspective for understanding regional integration, and relevant conclusions can inform environmental policy priorities for sustainable decision-making in urbanized areas.

Spatiotemporal Characteristics of Food Supply-Demand Balance in Uzbekistan under Different Scenarios.

The food supply-demand balance is a perpetual concern for many countries, especially developing countries, such as Uzbekistan. Using the land resource carrying capacity model, here, food supply and demand for the cereals and calories in Uzbekistan during 1995-2020 were revealed. Despite increased demand for cereals and calories, unstable crop production has led to volatile growth patterns. The carrying capacity of cropland resources under Uzbekistan's consumption standard shifted from overload to surplus and then to balance. Moreover, the carrying capacity of cropland resources under the healthy diet standard moved from balance to surplus in the past 25-years. Additionally, the calorific equivalent land resource carrying capacity under Uzbekistan's consumption standard fluctuated, with the carrying state shifting from balance to surplus, and the healthy diet standard still in overload. These findings can help guide sustainable production and consumption strategies in Uzbekistan and other countries by analyzing the consumption structure and changes in supply and demand relationships.

Does Nepal Have the Agriculture to Feed Its Population with a Sustainable Diet? Evidence from the Perspective of Human-Land Relationship.

Nepal is one of the least developed countries in the world, with more than 80% of the population engaged in agricultural production and more than two-fifths of the population still living below the poverty line. Ensuring food security has always been a key national policy in Nepal. Using a nutrient conversion model and an improved resource carrying capacity model as well as statistical data and household questionnaires, an analysis framework for food supply balance is developed in this study, which quantitatively analyzes the balance of food supply and demand in Nepal from the perspectives of food and calories during the period 2000-2020. Nepal's agricultural production and consumption have increased significantly, and the diet has been relatively stable over the past two decades. The diet structure is stable and homogeneous, with plant products occupying the absolute position in overall dietary consumption. The supply of food and calories varies widely from region to region. Although the increasing supply level at the national scale can meet the needs of the current population, the food self-sufficiency level cannot meet the needs of the local population development at the county level due to the influence of population, geographical location, and land resources. We found that the agricultural environment in Nepal is fragile. The government can improve agricultural production capacity by adjusting the agricultural structure, improving the efficiency of agricultural resources, improving the cross-regional flow of agricultural products, and improving international food trade channels. The food supply and demand balance framework provided a reference for achieving balance between the supply and demand of food and calories in a resource-carrying land and provides a scientific basis for Nepal to achieve zero hunger under the framework of the Sustainable Development Goals. Furthermore, development of policies in order to increase agricultural productivity will be critical for improving food security in agricultural countries such as Nepal.

The supply and demand balance of recyclable textiles in the Nordic countries.

The textile industry is on its early steps towards circular economy. Being a highly resource-intensive and waste-generating industry, it is essential to embrace fiber-to-fiber recycling in addressing the increasing textile waste problem. Several innovative initiatives are happening within this area, not least in the Nordic countries, where automated sorting and fiber-to-fiber recycling technologies and capacities are developing. These large investments require economy of scale; however, this is challenged by the fractioned supply due to the specific fiber requirements of the recycling facilities. To ensure economy of scale and support strategic planning, it is important to investigate the balance of the demand of those capacities with the supply of recyclables generated in the region. Local and regional perspectives are needed in order to avoid unnecessary transportation of low value materials. Based on a synthetises of existing textile flow studies and interviews with relevant actors in four Nordic countries, this study investigates the balance between the supply of recyclable textiles and the sorting and recycling capacity. This is accomplished by estimating the volumes of recyclables and their fiber composition (based on developed weighting average method) and comparing these with the current and upcoming capacities in each country and in the Nordics as a whole. The findings indicate that the upcoming automatic sorting and recycling capacity will be sufficient to deal with the total recyclable fraction in the Nordic region, except for some of the synthetic fibers. However, there are imbalances between supply and demand within individual countries, highlighting opportunities for collaboration.

Identifying Spatial Matching between the Supply and Demand of Medical Resource and Accessing Carrying Capacity: A Case Study of Shenzhen, China.

Previous Studies, such as the evaluation of the supply of and demand for regional medical resources and carrying capacity assessments, require further development. This paper aims to evaluate the carrying capacity and spatial distribution of medical resources in Shenzhen from the perspective of supply and demand, and to conduct a time-series variation of the coupling coordination degree from 1986 to 2019. The two-step floating catchment area method was employed to quantify the carrying capacity and coupling coordination degree method and spatial autocorrelation analysis were applied to analyze spatial distribution between supply and demand. The results were as follows. (1) The carrying capacity index in more than 50% of the districts was classified as low-grade. The percentage of regions with good grades was 8.27%. The regions with a high carrying capacity were distributed in the central and southeastern areas. (2) The coupling coordination continued to rise, increasing from 0.03397 in 1986 to 0.33627 in 2019. (3) The level of supply and demand for medical resources in Shenzhen increased from 1986 to 2019, and the highest degree of compatibility between the supply and the population size was largely concentrated in the western and eastern regions. This research can provide a theoretical reference for Shenzhen to rationally plan medical resources and improve the carrying capacity of medical resources.

Under-Oil Autonomously Regulated Oxygen Microenvironments: A Goldilocks Principle-Based Approach for Microscale Cell Culture.

Oxygen levels in vivo are autonomously regulated by a supply-demand balance, which can be altered in disease states. However, the oxygen levels of in vitro cell culture systems, particularly microscale cell culture, are typically dominated by either supply or demand. Further, the oxygen microenvironment in these systems is rarely monitored or reported. Here, a method to establish and dynamically monitor autonomously regulated oxygen microenvironments (AROM) using an oil overlay in an open microscale cell culture system is presented. Using this method, the oxygen microenvironment is dynamically regulated via the supply-demand balance of the system. Numerical simulation and experimental validation of oxygen transport within multi-liquid-phase, microscale culture systems involving a variety of cell types, including mammalian, fungal, and bacterial cells are presented. Finally, AROM is applied to establish a coculture between cells with disparate oxygen demands-primary intestinal epithelial cells (oxygen consuming) and Bacteroides uniformis (an anaerobic species prevalent in the human gut).

Research on the Matching Relationship between the Supply of Urban Ecological Recreational Space and the Demand of Residents-A Case Study of an Urban Development Area in Wuhan.

An urban ecological recreational space (UERS), which connects the natural environment with urban residents, is an important guarantee for developing a livable city and improving the well-being of residents. However, there is a serious imbalance between the supply of UERSs and the demand of residents in many big, rapidly developing cities. Previous studies usually used indicators such as scale or quantity to measure the supply level of UERS enjoyed by residents, ignoring its own quality differences. Therefore, taking the urban development area of Wuhan as the research object, we measured the quality of UERS from four dimensions using the entropy method and designed a method to measure the supply service level under the hierarchical travel threshold to analyze the supply level of UERSs based on a community unit. Finally, combined with the demand characteristics of different groups, the matching relationship between supply and demand of UERSs in each community is quantitatively analyzed. The results show the following: (1) The quality of UERS in urban development area of Wuhan varies greatly and its distribution is extremely uneven. (2) The level of supply services and the demand level vary greatly, and the overall performance has a trend of decreasing from the city center to the periphery. (3) The overall matching relationship between supply and demand of UERS is not ideal, and more than half of the communities are in supply deficit or without services. Our study provides a novel perspective on quantifying the supply-demand relationship of UERS. It can more accurately guide decision-makers and planners in determining areas with mismatches between the supply and demand of UERSs and in making targeted layouts of UERSs and relevant policies.

Multiscale research on spatial supply-demand mismatches and synergic strategies of multifunctional cultivated land.

Multifunctional cultivated land has both sides of supply and demand, and their matches are very important to boost the high-quality development of agriculture and rural areas. The supply-demand match index and GIS spatial analysis were employed to explore the supply-demand mismatches and synergic strategies of multifunctional cultivated land. Taking the Wuhan Metropolitan Area (WMA), China as an example, we obtained the following results: (1) There were obvious supply-demand mismatches of multifunctional cultivated land in the production function, ecological function, and landscape culture function. The spatial distribution of supply-demand mismatches of the three different functions of cultivated land is different. The supply of cultivated land production function is less than the demand, while the supply of landscape culture function is greater than the demand. The supply matches the demand of cultivated land in the ecological function. (2) The supply-demand mismatches of multifunctional cultivated land have scale effects. From the 1 km × 1 km grid scale to the township, county (district), and prefecture-level city scales, the proportion of deficit regions of production function and ecological function decreases with increasing scale. In contrast, the deficit regions of landscape culture function are always concentrated in the center of the WMA. It is considered that we should improve the supply of cultivated land in the production function, protect ecological function and enhance the demand of landscape culture function. Moreover, the management of multifunctional cultivated land needs to strengthen the multiscale spatial linkage and differential strategies of the supply side and demand side.

Aortic diastolic pressure decay modulates relation between worsened aortic stiffness and myocardial oxygen supply/demand balance after resistance exercise.

High-intensity resistance exercise (RE) increases aortic stiffness and decreases the index of myocardial oxygen supply/demand balance (Buckberg index, BI); there is a correlation between the changes in these parameters. Central hemodynamics during diastole can explain the correlation. We aimed to investigate whether the aortic diastolic decay index mediates the association between changes in aortic stiffness and BI by high-intensity RE. We evaluated the effect of high-intensity RE on aortic stiffness, BI, aortic decay index, and their associations in 52 young men. Subjects were studied under parallel experimental conditions on two separate days. The order of experiments was randomized between RE (5 sets of 10 repetitions at 75% of 1-repetition maximum) and sham control (seated rest). Aortic pulse wave velocity (PWV; index of aortic stiffness), BI, and aortic decay index were measured in all subjects. Aortic decay index was quantified by fitting an exponential curve: P(t) = P0e-λt (where λ is decay index, P0 is end-systolic pressure and t is time from end-systole). Aortic PWV and decay index increased and BI decreased after RE. RE conditions showed that change in the aortic decay index was associated with changes in aortic PWV and changes in aortic PWV were related to changes in BI, although the PWV-BI relationship was not significant after accounting for decay index change. Mediation analysis revealed the mediating effect of the aortic decay index on the relationship between changes in aortic PWV and BI. The present findings suggest that high-intensity RE-induced aortic stiffening worsens myocardial viability by accelerating aortic diastolic exponential decay.NEW & NOTEWORTHY Aortic pulse wave velocity (PWV) and diastolic decay index increased and Buckberg index (BI) decreased after resistance exercise (RE). Mediation analysis revealed a mediating effect of aortic decay index on the relationship between changes in aortic PWV and BI. The present study provides evidence that high-intensity RE-induced aortic stiffening accelerates aortic decay and aortic decay can account for the relationship between aortic stiffening and a deteriorated surrogate marker of myocardial oxygen supply/demand balance induced by high-intensity RE.

Assessment of cerebral oxygen supply-demand balance by near-infrared spectroscopy during induction of anesthesia in patients undergoing coronary artery bypass graft surgery: comparison of midazolam with propofol.

BACKGROUND: Near-infrared spectroscopy (NIRS) continuously measures regional cerebral oxygen saturation (rSO2) noninvasively and has been shown to detect even small changes in cerebral oxygen supply-demand balance. Although widely used, only the effect of midazolam on cerebral blood flow has been studied in humans and evidence is lacking about its effect on cerebral metabolic rate. We therefore evaluated the effect of midazolam on cerebral oxygen supply-demand balance with NIRS. METHODS: Sixty patients undergoing elective coronary artery bypass graft surgery were randomly allocated into either midazolam (n = 30) or propofol (n = 30) group. rSO2 was recorded before induction while patients were breathing room air as baseline, after pre-oxygenation with 100% oxygen, after administration of either midazolam or propofol, after completion of administration of sufentanil and after tracheal intubation. Hemodynamic variables including cardiac index and mixed venous oxygen saturation were recorded at the same time points. RESULTS: rSO2 and hemodynamic variables were similar between the groups throughout the study period. After pre-oxygenation, rSO2 significantly increased compared to baseline in each group, and did not show any additional increase after administration of either midazolam or propofol and sufentanil in both groups. CONCLUSIONS: Midazolam preserves cerebral blood flow-metabolism coupling to a similar degree to propofol as assessed by near infrared spectroscopy.

Assessment of cerebral oxygen supply-demand balance by near-infrared spectroscopy during induction of anesthesia in patients undergoing coronary artery bypass graft surgery: comparison of midazolam with propofol / 대한마취과학회지

BACKGROUND: Near-infrared spectroscopy (NIRS) continuously measures regional cerebral oxygen saturation (rSO2) noninvasively and has been shown to detect even small changes in cerebral oxygen supply-demand balance. Although widely used, only the effect of midazolam on cerebral blood flow has been studied in humans and evidence is lacking about its effect on cerebral metabolic rate. We therefore evaluated the effect of midazolam on cerebral oxygen supply-demand balance with NIRS. METHODS: Sixty patients undergoing elective coronary artery bypass graft surgery were randomly allocated into either midazolam (n = 30) or propofol (n = 30) group. rSO2 was recorded before induction while patients were breathing room air as baseline, after pre-oxygenation with 100% oxygen, after administration of either midazolam or propofol, after completion of administration of sufentanil and after tracheal intubation. Hemodynamic variables including cardiac index and mixed venous oxygen saturation were recorded at the same time points. RESULTS: rSO2 and hemodynamic variables were similar between the groups throughout the study period. After pre-oxygenation, rSO2 significantly increased compared to baseline in each group, and did not show any additional increase after administration of either midazolam or propofol and sufentanil in both groups. CONCLUSIONS: Midazolam preserves cerebral blood flow-metabolism coupling to a similar degree to propofol as assessed by near infrared spectroscopy.