Cumulative Quantity Research Articles

Machine Learning-Based Stroke Prediction: A Critical Analysis

Stroke is a critical public health issue that frequently has long-term impairment and negative effects. Devising innovative methods that enable timely and accurate identification and intervention is crucial. In this regard, machine learning (ML) and deep learning (DL) approaches of artificial intelligence (AI) play a crucial role in reducing the incidence of strokes. This study systematically analyzed articles from 2012 to 2022 using the PRISMA Method. PRISMA is a tool that facilitates researchers' access to an online platform for self-directed learning. The cumulative quantity of articles gathered for ten years reached 1405 from five databases. However, only 79 relevant articles were used for identification. The main objective was to provide a thorough taxonomy that classifies using and implementing machine learning approaches for stroke prediction. The results of this experiment confirm that machine-learning techniques have a great deal of potential for accurate stroke prediction. Nevertheless, challenges such as biased data and algorithms and the need for models that can be adjusted to accommodate various demographics and healthcare systems continue to exist. It is essential to recognize the need for additional research projects that thoroughly explore potential data biases, algorithmic biases, and the generalizability of models across various demographics and healthcare systems. More research is necessary to further the literature on the complete assessment of machine learning models in precisely forecasting stroke occurrences.

The effects of environmental evolution on runoff and hydrological health variations in the upper Shule River, Northwest China

Promptly grasping the process of runoff change and the mechanism of hydrological health (H) variation in inland river basins is essential for the optimal use of water resources in the arid area of Northwest China. In this study, the upper Shule River (USR) was selected as the research area. The Budyko equation and the slope changing ratio of cumulative quantity method (SCRCQ) were used to analyze the response of environmental changes to the evolution of runoff and hydrological health during 1956–2022. The findings showed that the streamflow at various time scales in the USR showed a significantly increased trend from 1956 to 2022. The change rate of annual maximum runoff (Rmax) was 3.3 times that of annual runoff (R), the change rate of R in the flood period was 2.4 times that in the non-flood period, and the change rate in summer was 5 times that in winter. The H of the USR indicated a downtrend during 1956–2022, and the H in the Ta period was better than that in the Tb period. June and August were the main periods of runoff increase and hydrological health evolution, and precipitation (P) was the main driving factor. The response of Rmax increased to climate variability and anthropogenic stressors was 50.42 % and 49.58 %, respectively. The response degrees of H to climate variability and anthropogenic stressors were 62.89 % and 37.11 %, respectively. In general, climate variation was the major factor in the increase of R and the decrease of H in the USR. The findings are useful for getting the streamflow evolution process and hydrologic cycle mechanism and playing a supporting role in the sustainable management of water resources in the future.

Evolution characteristics and attribution analysis of runoff in the coal mining area in northwest China: A case study of the Kuye River Basin

ABSTRACT The Kuye River Basin is the main coal-producing area in northwest China, and it is also a typical arid and semi-arid area. Under the combined influence of climate change and human activities, the runoff of the basin decreases noticeably. The Mann–Kendall trend test, the Hurst index, cumulative anomaly, and wavelet analysis were used to analyze the runoff evolution characteristics of the Kuye River, and the contributions of climate change and human activities to the runoff reduction were quantitatively separated by the slope-changing ratio of the cumulative quantity. The results showed that the runoff decreased significantly from 1970 to 2020, and there was an obvious abrupt change in 1996, while the change trends in precipitation and evaporation were not significant. The contributions of climate change and human activities to runoff reduction were 22.71 and 77.29%, respectively, and human activities have become the dominant factor in runoff variations. Coal mining and the implementation of soil and water conservation measures are considered to be the main human activities contributing to the reduction in runoff. In particular, mining activities reduce groundwater recharge to rivers, which provides a profound understanding of the effect of human activities in mining areas on runoff variation.

PH-Sensitive In Situ Gel of Mirtazapine Invasomes for Rectal Drug Delivery: Protruded Bioavailability and Anti-Depressant Efficacy.

The present research emphasizes fabrication alongside the assessment of an innovative nano-vesicular membranous system known as invasomes (NVMs) laden with Mirtazapine for rectal administration. This system could circumvent the confines of orally administered counterparts regarding dose schedules and bioavailability. Mirtazapine invasomes were tailored by amalgamating phospholipid, cineole, and ethanol through a thin-film hydration approach rooted in the Box-Behnken layout. Optimization of composition parameters used to fabricate desired NVMs' physicochemical attributes was undertaken using the Design-Expert® program. The optimal MRZ-NVMs were subsequently transformed to a pH-triggered in situ rectal gel followed by animal pharmacodynamic and pharmacokinetic investigations relative to rectal plain gel and oral suspension. The optimized NVMs revealed a diameter size of 201.3 nm, a z potential of -28.8 mV, an entrapment efficiency of 81.45%, a cumulative release within 12 h of 67.29%, and a cumulative daily permeated quantity of 468.68 µg/cm2. Compared to the oral suspension, pharmacokinetic studies revealed a 2.85- and 4.45-fold increase in calculated rectal bioavailability in circulation and brain, respectively. Pharmacodynamic and immunohistopathology evaluations exposed superior MRZ-NVMs attributed to the orally administered drug. Consequently, rectal MRZ-NVMs can potentially be regarded as a prospective nanoplatform with valuable pharmacokinetics and tolerability assets.

China’s spatial and temporal position in the global research network of information behavior and its current development dynamics

PurposeThis paper aims to objectively present the research dynamics of China in the field of information behavior and its development trends. Firstly, it incorporates China’s research in the field of information behavior into the global research network of information behavior, analyzing the changes in the status of Chinese scholars and their research institutions in the global research network from 1991 to 2022, the trends in publication volume and the cooperation relationships with other countries. Then, it conducts a detailed analysis of China’s research categories, groups, theoretical models and hot topics in different information contexts in the past five years (2018–2022).Design/methodology/approachThe study retrieved research literature related to information behavior in China from 1991 to 2022 in the Web of Science database. It then utilized a national/institutional cooperation network map to analyze the changes in the status of Chinese scholars/institutions in the global research network during this period, publication volume trends and cooperation relationships with other countries. Furthermore, it employed keyword co-occurrence network maps to analyze the key categories, groups, theories and models of China’s research in different information contexts in the past five years. Based on this, it used keyword clustering network maps to analyze the hot topics of China’s research in different information contexts in the past five years.Findings(1) China’s research in the field of information behavior started relatively late, but the volume of publications has grown rapidly since 2004, currently ranking second globally in cumulative publication quantity. However, the influence of the literature published by China is limited, and there is a lack of research institutions with global influence. (2) In the last five years, China has conducted extensive research in various information contexts. Among these, most research was conducted in work contexts, followed by healthcare contexts, especially studies related to epidemics. (3) Current research on information behavior in China is characterized by expanded and refined research groups, diversified research categories, continuous expansion and enrichment of research contexts, increased interdisciplinary nature of research and continuous innovation in research methods and theoretical models.Originality/valueThis study, utilizing a scientific knowledge map, elucidates China’s position in global information behavior research, with a specific emphasis on analyzing China’s research hot topics and trends in this field over the past five years. It aims to provide valuable resources for scholars interested in understanding the status of information behavior research in China and to offer some guidance for scholars currently or intending to engage in information behavior research.

Design Formulation and Evaluation of Anti Migraine Mouth Dissolving Tablets Using Different Super Disintegrants

The main objective of this research was to create and evaluate the efficacy of orally disintegrating tablets containing sumatriptan succinate at a dosage of 25 milligrammes, a medicine commonly prescribed for the treatment of migraines. The tablets are made using the direct compression method. In order to achieve best results, the formulations were enriched with microcrystalline cellulose of varying composition (Avicel PH 102), mannitol as a diluent, crospovidone, croscaramellose, and sodium starch glycollate as superdisintegrants. Carbomer (carbopol 940), Sodium CMC, and Sodium Alginate were among the other excipients that were used. When used at varying doses, these excipients act as disintegrants. In addition, magnesium stearate was used as a substance to reduce friction, while talc was used as a substance to improve flow. We assessed each of the excipients to ascertain their compatibility with the model drug. The findings revealed no occurrence of any physical or chemical interaction. Before compression, the preformulation features of the tablet blend were examined. The criteria considered were bulk density, tapped density, compressibility index, and hausner ratio. An assessment was carried out on central tablets to ascertain their dimensions, firmness, tendency to crumble, variability in weight, rate of disintegration, and uniformity of drug content properties. Furthermore, an investigation was conducted to examine the impact of these variables on the release of the drug. The drug release studies were performed in vitro using the USP dissolving apparatus-II (paddle type) with a phosphate buffer solution at a pH of 6.8. The experiments were conducted at a speed of 50 revolutions per minute at a temperature of 37 degrees Celsius, with a standard deviation of 5 degrees Celsius. The sampling was conducted at consistent intervals of 2, 4, 6, 8, and 10 minutes. After each withdrawal, an equivalent volume of dissolving medium was replaced with the sample. The ultraviolet (UV) method is employed to evaluate the cumulative quantity of medications that have been discharged at different time intervals. Based on the evaluation results, the F-3 trial formulation, which included 6% crospovidone, was selected as the superior formulation among the superdisintegrants. Conversely, the F-10 trial formulation, which included 2% carbopol 940p, was selected as the superior formulation compared to other basic disintegrants.

Sensitivity of Runoff to Climatic Factors and the Attribution of Runoff Variation in the Upper Shule River, North-West China

Climate change and human activities exert significant impact on the mechanism of runoff generation and confluence. Comprehending the reasons of runoff change is crucial for the sustainable development of water resources. Taking the Upper Shule River as the research area, the M-K test and the moving t test were used to diagnose the runoff mutation time. Furthermore, the slope changing ratio of cumulative quantity method (SCRCQ), climate elasticity method, and Budyko equation were utilized to quantitatively evaluate the impacts and contribution rates of climate change and human activities. The following results were obtained: (1) The Upper Shule River experienced a significant increase in runoff from 1972 to 2021, with 1998 marking the year of abrupt change. (2) The runoff sensitivity showed a downward trend from 1972 to 2021. The main factor affecting the decrease in runoff sensitivity was the characteristic parameters of underlying surface (n), followed by precipitation (P), while the influence of potential evapotranspiration (ET0) was the weakest. (3) The response of runoff changes to runoff sensitivity and influencing factors were 90.32% and 9.68%, respectively. (4) The results of three attribution methods indicated that climate change was the primary factor causing the alteration of runoff in the Upper Shule River. The research results supplement the hydrological change mechanisms of the Upper Shule River and provide a scientific basis for future water resources management and flood control measures.

Analysis of Changes in Runoff and Sediment Load and Their Attribution in the Kuye River Basin of the Middle Yellow River Based on the Slope Change Ratio of Cumulative Quantity Method

Climate change and human activities exert significant influence on the water–sediment relationship in arid and semi-arid regions. Therefore, comprehending the underlying mechanisms is crucial for the effective management of water and soil resources, as well as integrated watershed management. This research focuses on the Kuye River watershed (KYH_W) in the middle reaches of the Yellow River in China, along with its sub-watersheds Wangdaohengtazi (WDHT_SW) and Xinmiaosi (XM_SW). This paper utilizes the Mann–Kendall non-parametric test and the double cumulative curve method to examine the interannual trends of runoff, sediment transport, precipitation, temperature, and NDVI factors. Furthermore, the method of the slope change ratio of cumulative quantity (SCRCQ) is utilized to quantitatively evaluate the impacts and contribution rates of climate change and human activities on water–sediment changes within each watershed. The results are as follows: (1) From 1969 to 2019, the entire watershed experienced a significant decrease in both runoff and sediment transport, with 1997 marking the year of abrupt change. However, following 2012, the KYH_W and WDHT_SW exhibited a noticeable rebound in runoff. (2) Human activities predominantly contribute to the reduction in water and sediment in the watershed. (3) After the abrupt change, between 1998 and 2011, the contribution rates of climate change and human activities to the annual runoff reduction in the entire KYH_W reached 33% and 64%, respectively. Moreover, these rates for sediment transport reduction reached 26% and 74%, respectively. Subsequently, after 2012, the contribution rates of both factors to the increase in watershed runoff reached 29% and 71%, respectively. Factors other than the NDVI, within human activities, played a dominant role in augmenting the watershed’s runoff. (4) Prior to 2011, changes in vegetation cover resulting from the Grain for Green Program, as measured by the NDVI, emerged as the primary factor responsible for reduced runoff in the watershed. Conversely, factors other than the NDVI assumed dominance in reducing sediment transport. The SCRCQ method offers a quantitative approach to assessing water–sediment changes. Based on this method, the study further underscores the substantial impacts of climate change and human activities on variations in runoff and sediment transport within the KYH_W in the middle reaches of the Yellow River. Notably, the water–sediment changes in the KYH_W exhibit distinct stage-wise and spatial discrepancies, which warrant increased attention in future research endeavors.

Species diversity and interspecific information flow.

Interspecific information flow is known to affect individual fitness, population dynamics and community assembly, but there has been less study of how species diversity affects information flow and thereby ecosystem functioning and services. We address this question by first examining differences among species in the sensitivity, accuracy, transmissibility, detectability and value of the cues and signals they produce, and in how they receive, store and use information derived from heterospecifics. We then review how interspecific information flow occurs in communities, involving a diversity of species and sensory modes, and how this flow can affect ecosystem-level functions, such as decomposition, seed dispersal or algae removal on coral reefs. We highlight evidence that some keystone species are particularly critical as a source of information used by eavesdroppers, and so have a disproportionate effect on information flow. Such keystone species include community informants producing signals, particularly about predation risk, that influence other species' landscapes of fear, and aggregation initiators creating cues or signals about resources. We suggest that the presence of keystone species means that there will likely be a positive relationship in many communities between species diversity and information through a 'sampling effect', in which larger pools of species are more likely to include the keystone species by chance. We then consider whether the number and relative abundance of species, irrespective of the presence of keystone species, matter to interspecific information flow; on this issue, the theory is less developed, and the evidence scant and indirect. Higher diversity could increase the quantity or quality of information that is used by eavesdroppers because redundancy increases the reliability of information or because the species provide complementary information. Alternatively, there could be a lack of a relationship between species diversity and information if there is widespread information parasitism where users are not sources, or if information sourced from heterospecifics is of lower value than that gained personally or sourced from conspecifics. Recent research suggests that species diversity does have information-modulated community and ecosystem consequences, especially in birds, such as the diversity of species at feeders increasing resource exploitation, or the number of imitated species increasing responses to vocal mimics. A first step for future research includes comprehensive observations of information flow among different taxa and habitats. Then studies should investigate whether species diversity influences the cumulative quality or quantity of information at the community level, and consequently ecosystem-level processes. An applied objective is to conserve species in part for their value as sources of information for other species, including for humans.

Joint transcriptomic and cytometric study of children with peanut allergy reveals molecular and cellular cross talk in reaction thresholds

BackgroundReaction thresholds in peanut allergy are highly variable. Elucidating causal relationships between molecular and cellular processes associated with variable thresholds could point to therapeutic pathways for raising thresholds. ObjectiveTo characterize molecular and cellular systemic processes associated with reaction threshold in peanut allergy and causal relationships between them. Methods105 children ages 4 to 14 years with suspected peanut allergy underwent double-blind, placebo-controlled food challenges to peanut. The cumulative peanut protein quantity eliciting allergic symptoms was considered the reaction threshold for each child. Peripheral blood samples collected at 0, 2, and 4 hours after challenge start were used for RNA sequencing, whole blood staining, and cytometry. Statistical and network analyses were performed to identify associations and causal mediation between the molecular and cellular profiles and peanut reaction threshold. ResultsWithin the cohort (n=105), 81 (77%) experienced allergic reactions after ingesting varying quantities of peanut, ranging from 43 to 9043 mg cumulative peanut protein. Peripheral blood expression of transcripts (e.g., IGF1R, FDR=5.4e-5 and PADI4, FDR=5.4e-5) and neutrophil abundance (FDR=9.5e-4) were associated with peanut threshold. Co-expression network analyses revealed that the threshold-associated transcripts were enriched in modules for FcγR-mediated phagocytosis (FDR=3.2e-3) and TLR (FDR=1.4e-3) signaling. Bayesian network, key driver, and causal mediation analyses identified key drivers (AP5B1, KLHL21, VASP, TPD52L2 and IGF2R) within these modules involved in bi-directional causal mediation relationships with neutrophil abundance. ConclusionKey driver transcripts in FcγR-mediated phagocytosis and TLR signaling bi-directionally interact with neutrophils in peripheral blood and are associated with reaction threshold in peanut allergy.

Comparative analysis of sterile mosquito release strategies based on a population suppression model

<p>In this paper, we proposed a model for suppressing mosquito populations, evaluating various release strategies for sterilized mosquitoes, including constant continuous release, open-loop control, closed-loop control, and composite control strategies. We established release amount thresholds for each strategy to ensure the ultimate extinction of the wild population. Through numerical simulations, we validated our theoretical results and assessed the efficacy of each strategy. The results indicated that the closed-loop control mechanism significantly enhanced population suppression effectiveness. Higher intensity control notably shortened the control duration, and strategies that incorporated shorter release periods and more frequent population assessments markedly reduced the cumulative release quantity. Furthermore, we found that, compared to closed-loop control, the composite control strategy reduced single release amounts but did not show advantages in other aspects at low control intensities. However, it significantly decreased the cumulative release quantity at high control intensities.</p>

An improved methodology for quantifying the impact of human activities on hydrological drought change

Study regionUpper Shiyang River in the eastern Qilian Mountains, China. Study focusQuantifying the impacts of anthropogenic and climate change on wet and dry hydrological variability was done by improving the Slope Change Ratio of Cumulative Quantities (ISCRCQ) method. New hydrological insights for the regionThe scientific method is critical to quantify the driving factors of dry-wet hydrological changes. In this study, the slope change ratio of cumulative quantity (SCRCQ) method was improved to quantify the impacts of human activities and climate change on dry-wet hydrological changes. The results show a hydrological aridification trend at an annual scale from 1961 to 2016 in the upper reaches of the Shiyang River. However, the dry-wet hydrological change trends of the six tributaries differed: the hydrological humidification of the four western tributaries was apparent, while the remaining tributaries showed hydrological aridification. The influences of human activities and climate change on dry-wet hydrological changes were also evidently distinct in the different tributaries. Changing in climate is a vital factor triggering the dry-wet hydrological changes in the western tributaries, while human activities have completely changed the direction of the dry-wet hydrological changes and intensified the hydrological aridification in the eastern tributaries. Human activities have resulted in an increase both in the frequency of droughts and in the risk of socio-economic droughts. Thus, human activities in the region of eastern tributaries should be controlled within reasonable limits.

Characteristics of Pressure Stimulated Current and Damage Evolution of Granite under Progressive Uniaxial Loading

The application of load on rock materials stimulates a weak current known as Pressure Stimulated Current (PSC). This study focuses on investigating the damage evolution of granite rocks through the analysis of PSC responses. Uniaxial loading experiments were conducted on granite samples, and the accompanying PSC was measured in real-time. The relationship between PSC characteristics and mechanical behaviors of granite was examined to explore precursory information related to granite failure. The damage evolution of granite was assessed using a damage variable defined as the cumulative charge (time integral of PSC). The results clearly demonstrate a close correlation between the variation of PSC and the mechanical behaviors of rock. Specifically, during the compaction and elastic deformation stages, PSC exhibits a slow and linear increase. However, once deformation enters the plastic stage, PSC demonstrates an accelerated upward trend. Additionally, it was observed that a stress drop coincides with an abnormal increase in PSC, which is followed by a rapid decay. The fluctuation observed after the abnormal increase in PSC during the accelerated growth phase can serve as a precursor of rock failure. Furthermore, the cumulative charge quantity effectively correlates with the damage process of granite samples. The stress–strain curve obtained from a theoretical constitutive model, established based on the damage variable represented by normalized cumulative charge, aligns reasonably well with the experimental results, affirming that the defined damage variable accurately reflects the damage evolution process of rocks. It is hypothesized that PSCs are carried by electrons within the rocks, which are stimulated by electron diffusion during deformation and experience a sharp increase upon rock fracturing. The research findings hold theoretical significance for predicting rockburst incidents using the PSC method.

Examining adverse childhood experiences and attention deficit/hyperactivity disorder: A systematic review

AbstractAdverse childhood experiences (ACEs) comprise many dimensions of abuse and neglect in early development. Attention deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder that often begins in childhood. In this review, we investigated the associations between ACEs and ADHD in children. Specifically, the focus is to determine the extent of the relationship between ACE type, cumulative number, and ADHD severity. Furthermore, this study explored all aspects of the bidirectional nature of this relationship including how children with ADHD may experience greater ACEs and the potential contribution of confounding and mediating variables including comorbid conditions and resilience. Selected studies were published between January 2015 and January 2023 on PsychInfo, Google Scholar, PubMed, and Scopus. Selected studies included: (1) The main age group of the study was children; (2) The children had to have been diagnosed with or have parent‐reported ADHD; and (3) The research must include ACE. Case studies and those not meeting the inclusion criteria were excluded from this review. Ultimately, 43 studies met the inclusion criteria, were included in this review, and were evaluated using the appropriate risk of bias assessment tools. These studies supported a positive association between ACEs and ADHD including cumulative quantity and select types of ACEs increasing ADHD severity. Previous literature has primarily utilized observational methodologies which prevent researchers from establishing if there are causal associations and if there is a temporal order to ACEs and ADHD development. This review also provides implications for future research.

Quantitative evaluation of the influence of rainfall changes and groundwater exploitation on the groundwater level: a case study of the northern Huangqihai Basin, China

Abstract Based on the hydrogeological perspective, the variation in the groundwater level (W) was selected as the analysis factor, and the rainfall changes and groundwater exploitation (QGE) were considered to be the influencing factors. The influence of the two factors on W in the northern Huangqihai Basin was analyzed qualitatively and quantitatively. Results showed that both rainfall and QGE showed increasing trends from 1996 to 2020, while the W values decreased. The correlation between QGE and W was weaker in wet years than in normal years but was the highest in dry years. The mutation time was determined to be 2004. Based on the slope-changing ratio of the cumulative quantity method and the elastic coefficient method, it was determined that the contribution of rainfall changes to W was 22.08% and that of QGE was 77.92%. This study highlights the effectiveness of the integration of qualitative analyses and quantitative evaluation for identifying the influence of external factors on groundwater and well documents that the elastic coefficient method can be used in this field. More attention should be focused on the scientific management of QGE to minimize its negative influence on the sustainable development of groundwater.

Analysis of the Imperial Rent of Reserve Currency

This article provides an analysis of the economic cost incurred by the world through the use of the fiat international reserve currency since the end of the 1971 gold standard system. The article uses the Quantity Theory of Money to provide an empirical manifestation of how reserve currency yields income to its issuing country through the provision of an inflation buffer, which is equivalent to what the article frames as an imperial rent of reserve currency. The article then provides a method to estimate the cumulative quantity of this rent by using data on the broad money supply, nominal GDP, and world total official foreign exchange holdings of the currency of the country in question. The article estimates that the quantity of the imperial rent of reserve currency that accrued to the four major reserve currency-issuing states (US, Euro area, UK, Japan) from the end of the gold standard until the end of 2021, which was accumulated through the official channel only, is of a value equivalent to 11.1 trillion USD, 71 % of this amount went to the US singly.

Multiple waves of COVID-19: a pathway model approach.

A generalized pathway model, with time-dependent parameters, is applied to describe the mortality curves of the COVID-19 disease for several countries that exhibit multiple waves of infections. The pathway approach adopted here is formulated explicitly in time, in the sense that the model's growth rate for the number of deaths or infections is written as an explicit function of time, rather than in terms of the cumulative quantity itself. This allows for a direct fit of the model to daily data (new deaths or new cases) without the need of any integration. The model is applied to COVID-19 mortality curves for ten selected countries and found to be in very good agreement with the data for all cases considered. From the fitted theoretical curves for a given location, relevant epidemiological information can be extracted, such as the starting and peak dates for each successive wave. It is argued that obtaining reliable estimates for such characteristic points is important for studying the effectiveness of interventions and the possible negative impact of their relaxation, as it allows for a direct comparison of the time of adoption/relaxation of control measures with the peaks and troughs of the epidemic curve.

Historical red-lining is associated with fossil fuel power plant siting and present-day inequalities in air pollutant emissions

Stationary sources of air pollution are disproportionately located in communities of colour, but the causes for this disparity are unclear. Here we assess whether racialized appraisals of investment risk (‘red-lining’) undertaken by the US federal Home Owners’ Loan Corporation in the 1930s influenced the subsequent siting of fossil fuel power plants. Across 8,871 neighbourhoods in 196 US urban areas, we observed a stepwise correlation between risk grade, number of power plants and cumulative quantity of power plant emissions upwind and within 5 km. Controlling for pre-existing power plants, neighbourhoods deemed ‘hazardous’ (D grade, ‘red-lined’) had a higher likelihood of a fossil fuel power plant being sited between 1940 and 1969 (72%), 1970 and 1999 (20%) and 2000 and 2019 (31%), and higher average present-day emissions of nitrous oxides (82%), sulfur dioxide (38%) and fine particulate matter (63%) compared with ‘declining’ (C-graded) neighbourhoods. Our results suggest racism in the housing market contributed to inequalities in present-day power plant emissions burdens.

Response of runoff variation to the changing environments of karst regions in southwest China

How streamflow responds to changing environmental conditions is critical for a better understanding hydrological processes in ecologically vulnerable areas such as the karst region of southwest China. The Budyko framework and slope change ratio of cumulative quantity method (SCRCQ) were used to identify and quantify the contributions of changing environmental factors to streamflow variations for 8 large catchments in the region. Sensitivity analysis showed that interannual variation in runoff over 1960–2016 was more sensitive to land characteristics than to climatic factors. The contribution of climatic factors ranged from -95 to 261%, whereas that of land characteristics from -161 to 195%. Parameter values increased linearly as NDVI increased over time, which were also related to the fraction of carbonate rocks in these catchments among the 8 catchments examined. Vegetation cover, topography, and underlying geology as catchment characteristics in addition to climate affect the streamflow variations the karst region in southwest China.

Modeling the impact of nickel recycling from batteries on nickel demand during vehicle electrification in China from 2010 to 2050

China is promoting the production and use of electric vehicles (EVs) to achieve carbon neutrality. However, the shift will drive higher demand and tighter supply of nickel in China. We develop a stock–driven bottom–up dynamic substance flow analysis (SFA) model to simulate the demand trends of various EVs under 3 scenarios, the flow of nickel under 9 scenarios and the amount of recoverable nickel under 27 scenarios in China's EV industry from 2010 to 2050. The results indicate that China's current production capacity and primary reserves of nickel cannot meet the growing nickel demand, especially under the High EVs–LNCT scenarios, and closed–loop nickel recovery from EV batteries can effectively alleviate the demand–supply contradiction. In different scenarios, the annual recycling nickel could cover between 67.7 % and 96.6 % of the demand for EV batteries in 2050, and between 37.9 % and 58.1 % in terms of the cumulative quantity by 2050. When the low nickel battery technology is adopted and the recovery efficiency is rapidly improved, the recovered nickel would meet the demand for EV batteries to the highest degree. Therefore, sufficient attention should be paid to low–nickel battery technology and efficient recycling of spent EV batteries, which is of great significance to ensure the development of EV industry and the availability of nickel in China.