Central Nervous System Control of Glucose Homeostasis: A Therapeutic Target for Type 2 Diabetes?

Historically, pancreatic islet beta cells have been viewed as principal regulators of glycemia, with type 2 diabetes (T2D) resulting when insulin secretion fails to compensate for peripheral tissue insulin resistance. However, glycemia is also regulated by insulin-independent mechanisms that are dysregulated in T2D. Based on evidence supporting its role both in adaptive coupling of insulin secretion to changes in insulin sensitivity and in the regulation of insulin-independent glucose disposal, the central nervous system (CNS) has emerged as a fundamental player in glucose homeostasis. Here, we review and expand upon an integrative model wherein the CNS, together with the islet, establishes and maintains the defended level of glycemia. We discuss the implications of this model for understanding both normal glucose homeostasis and T2D pathogenesis and highlight centrally targeted therapeutic approaches with the potential to restore normoglycemia to patients with T2D.

Storage, Disposal, and Use of Opioids Among Cancer Patients in Central China: A Multi-Center Cross-Sectional Study.

OBJECTIVE: Unsafe opioid-related practices can lead to abuse, diversion, and accidental overdoses. In this study, we aimed to describe the patterns and beliefs regarding the storage, disposal, and use of opioids among Chinese patients with cancer in their home settings, which remain unclear. METHODS: A multicenter cross-sectional survey was conducted in Hubei Province from October 2022 to June 2023. We collected information on the storage, disposal, and use of opioids among cancer pain inpatients in the oncology department. Logistic regression was used to estimate the factors associated with unsafe disposal and use of opioids. RESULTS: The survey included 221 patients with a median age of 62 years. Only 3.2% stored their opioids under lock and key, and 49.8% were unaware of proper disposal methods. Nearly one-fifth (19.5%) reported having received information on the safe storage (14.0%) and/or disposal (10.0%) of opioids. A total of 44.3% reported unsafe use by sharing (1.8%), losing (4.1%), or taking opioids at a higher dose than prescribed (42.5%). Patients who did not receive information on the safe disposal of opioids (OR = 4.57, P = .0423), had a history of alcohol use (OR = 1.91, P = .0399), and used opioids other than morphine (OR = 2.31, P = .0461) had higher odds of unsafe disposal practices. Individuals with an associate degree/bachelor's degree or above were less likely to dispose of (OR = 0.36, P = .0261) and use (OR = 0.31, P = .0127) opioids unsafely. CONCLUSION: A significant proportion of Chinese patients with cancer exhibit unsafe practices in the storage, disposal, and use of opioids. The study highlights an urgent need for implementing routine education programs and drug "take-back" initiatives to improve opioid-related practices.

Activation of interleukin 33-NFκB axis in granulosa cells during atresia and its role in disposal of atretic follicles†.

It has been previously shown that the cytokine interleukin 33 is required for two processes, i.e., autophagic digestion of granulosa cells and recruitment of macrophages into atretic follicles, for full disposal of atretic follicles. Now, this study shows that activation of interleukin 33-suppression of tumorigenicity 2-Nuclear Factor ĸB (NFκB) axis in granulosa in early atretic follicles may regulate those two events. Injection of human chorionic gonadotropin has been shown to induce a transient peak of interleukin 33 expression with synchronized atresia. In this model, interleukin 33-independent expression of suppression of tumorigenicity 2 in granulosa cells was detected in early atretic follicles before macrophage invasion. The activation of NFκB pathway in ovaries was further demonstrated in vivo in Tg mice with luciferase-reporter for NFκB activation; the activation was microscopically localized to granulosa cells in early atretic follicles. Importantly, antibody blockage of interleukin 33 or interleukin 33 Knock-out (KO) (Il33-/-) not only inhibited NFκB activity in ovaries, but it also altered expression of two key genes, i.e., reduction in proinflammatory interleukin6 (IL6) expression, and a surge of potential autophagy-inhibitory mammalian target of rapamycin (mTOR) expression in atretic follicles. By contrast, apoptosis and other genes, such as interleukin1ß (IL1ß) were not affected. In conclusion, in parallel to apoptosis, atresia signals also trigger activation of the interleukin 33-suppression of tumorigenicity 2-NFκB pathway in granulosa, which leads to (1) down-regulated expression of mTOR that is a negative regulator of autophagy and (2) up-regulated expression of proinflammatory IL6.

Insulin resistance assessed by estimated glucose disposal rate and risk of incident cardiovascular diseases among individuals without diabetes: findings from a nationwide, population based, prospective cohort study.

BACKGROUND: Recent studies have suggested that insulin resistance (IR) contributes to the development of cardiovascular diseases (CVD), and the estimated glucose disposal rate (eGDR) is considered to be a reliable surrogate marker of IR. However, most existing evidence stems from studies involving diabetic patients, potentially overstating the effects of eGDR on CVD. Therefore, the primary objective of this study is to examine the relationship of eGDR with incidence of CVD in non-diabetic participants. METHOD: The current analysis included individuals from the China Health and Retirement Longitudinal Study (CHARLS) who were free of CVD and diabetes mellitus but had complete data on eGDR at baseline. The formula for calculating eGDR was as follows: eGDR (mg/kg/min) = 21.158 - (0.09 × WC) - (3.407 × hypertension) - (0.551 × HbA1c) [WC (cm), hypertension (yes = 1/no = 0), and HbA1c (%)]. The individuals were categorized into four subgroups according to the quartiles (Q) of eGDR. Crude incidence rate and hazard ratios (HRs) with 95% confidence intervals (CIs) were computed to investigate the association between eGDR and incident CVD, with the lowest quartile of eGDR (indicating the highest grade of insulin resistance) serving as the reference. Additionally, the multivariate adjusted restricted cubic spine (RCS) was employed to examine the dose-response relationship. RESULTS: We included 5512 participants in this study, with a mean age of 58.2 ± 8.8 years, and 54.1% were female. Over a median follow-up duration of 79.4 months, 1213 incident CVD cases, including 927 heart disease and 391 stroke, were recorded. The RCS curves demonstrated a significant and linear relationship between eGDR and all outcomes (all P for non-linearity > 0.05). After multivariate adjustment, the lower eGDR levels were founded to be significantly associated with a higher risk of CVD. Compared with participants with Q1 of eGDR, the HRs (95% CIs) for those with Q2 - 4 were 0.88 (0.76 - 1.02), 0.69 (0.58 - 0.82), and 0.66 (0.56 - 0.79). When assessed as a continuous variable, per 1.0-SD increase in eGDR was associated a 17% (HR: 0.83, 95% CI: 0.78 - 0.89) lower risk of CVD, with the subgroup analyses indicating that smoking status modified the association (P for interaction = 0.012). Moreover, the mediation analysis revealed that obesity partly mediated the association. Additionally, incorporating eGDR into the basic model considerably improve the predictive ability for CVD. CONCLUSION: A lower level of eGDR was found to be associated with increased risk of incident CVD among non-diabetic participants. This suggests that eGDR may serve as a promising and preferable predictor and intervention target for CVD.

Frequency of prediabetes in individuals with increased adiposity and metabolically healthy or unhealthy phenotypes.

AIMS: To utilize the estimated glucose disposal rate (eGDR) index of insulin sensitivity, which is based on readily available clinical variables, namely, waist circumference, hypertension and glycated haemoglobin, to discriminate between metabolically healthy and unhealthy phenotypes, and to determine the prevalence of prediabetic conditions. METHODS: Non-diabetic individuals (n = 2201) were stratified into quartiles of insulin sensitivity based on eGDR index. Individuals in the upper quartiles of eGDR were defined as having metabolically healthy normal weight (MHNW), metabolically healthy overweight (MHOW) or metabolically healthy obesity (MHO) according to their body mass index, while those in the lower quartiles were classified as having metabolically unhealthy normal weight (MUNW), metabolically unhealthy overweight (MUOW) and metabolically unhealthy obesity (MUO), respectively. RESULTS: The frequency of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and IFG + IGT status was comparable among the MHNW, MHOW and MHO groups, while it increased from those with MUNW status towards those with MUOW and MUO status. As compared with participants with MHNW, the odds ratio of having IFG, IGT, or IFG + IGT was significantly higher in participants with MUOW and MUO but not in those with MUNW, MHOW and MHO, respectively. CONCLUSIONS: A metabolically healthy phenotype is associated with lower frequency of IFG, IGT, and IFG + IGT status across all body weight categories.

Decreasing Greenhouse Gas Emissions from the Municipal Solid Waste Sector in Chinese Cites.

Municipal solid waste (MSW) management systems play a crucial role in greenhouse gas (GHG) emissions in China. Although the government has implemented many policies to improve the MSW management system, the impact of these improvements on city-level GHG emission reduction remains largely unexplored. This study conducted a comprehensive analysis of both direct and downstream GHG emissions from the MSW sector, encompassing sanitary landfill, dump, incineration, and biological treatment, across 352 Chinese cities from 2001 to 2021 by adopting inventory methods recommended by the Intergovernmental Panel on Climate Change (IPCC). The results reveal that (1) GHG emissions from the MSW sector in China peaked at 70.6 Tg of CO2 equiv in 2018, followed by a significant decline to 47.6 Tg of CO2 equiv in 2021, (2) cities with the highest GHG emission reduction benefits in the MSW sector were historical emission hotspots over the past 2 decades, and (3) with the potential achievement of zero-landfilling policy by 2030, an additional reduction of 203.7 Tg of CO2 equiv is projected, with the emission reduction focus toward cities in South China (21.9%), Northeast China (17.8%), and Southwest China (17.3%). This study highlights that, even without explicit emission reduction targets for the MSW sector, the improvements of this sector have significantly reduced GHG emissions in China.

Injection-induced basement seismicity beneath the Raton Basin: constraints from refined fault architectures and basin structure.

Intraplate earthquakes induced by anthropogenic fluid injection present unexpected seismic risk to previously quiescent or low seismicity-rate regions. Despite many studies of induced seismicity, there are relatively few with detailed openly accessible constraints on the interaction between seismic sources and subsurface structures. In this study of the Raton Basin, we refine source observations from a dense nodal array and constrain basin structure using teleseismic receiver functions. The cross-correlation-based relocated hypocentres and a new set of focal mechanisms light up active fault segments and show clear spatiotemporal patterns. The geometric complexity of reactivated fault clusters appears greatest near higher rate injection wells. Simpler normal fault structure is found farther from injection wells and near abrupt structural transitions suggested by receiver functions. While less induced seismicity in the crystalline basement is expected when injection is >1 km from the top of the basement (like Raton), our receiver function analysis identified a basin thickness ~3 km beneath the nodal array and lateral variations in sedimentary structures. Our results explain potential fluid connectivity between the injection depths focused at ~1-1.5 km below the surface and basement fault activity that begins at ~3 km and reaches peak activity at ~4-8 km depths. This article is part of the theme issue 'Induced seismicity in coupled subsurface systems'.

Disposal and utilization of dead animals during breeding in livestock and poultry farming by means of synthetic microbiota.

The disposal of animal remains resulting from breeding is a significant challenge that impacts the industry's growth. To address the issues with current treatment methods, such as the large space required for corpse storage, and the high energy consumption of pyrolysis. Three strains with high protease and lipase production and one strain with high keratinase production were screened. The virulence genes were evaluated, the synthesis gene clusters of degrading enzymes were mined, secondary metabolites of each strain were analyzed, and the bacterial community with both growth rate and enzyme production ability was developed. Therefore, a microbial degradation method with mild reaction conditions and rapid liquefaction of animal residues was developed. The liquid degradation of four common farm-raised animal residues (sheep, cattle, chickens, and pigs) was tested under laboratory conditions. The results showed that the liquid degradation of animal residues was achieved within 144 h, transforming the months-long anaerobic process of traditional compost fermentation process into a mere 6 days' anaerobic process. N, P, K plant nutrients accounted for 15% of the total matrix, pH value was 5.5-6.7, heavy metal content was less than 0.2 mg L-1. Designed and improved fermentation equipment, produced a 3 m³ fermentation equipment, used in chicken, pig two types of animal residues pilot test. The emissions of greenhouse gases such as CO2 in the entire degradation process were 1.6 × 104 ppm, which was 481 times less than that of composting by 7.7 × 106. This study provides a solution for the treatment of dead livestock and poultry, which has promotional and practical value.

The potential of glucose management indicator for the estimation of glucose disposal rate in people with type 1 diabetes.

BACKGROUND AND AIMS: Insulin resistance is a growing feature in type 1 diabetes (T1D). It can be quantified by calculating the estimated glucose disposal rate (eGDR) with the Epstein's formula, which includes laboratory-measured glycated hemoglobin (HbA1c). We aimed the current research to assess the agreement between the conventional eGDR formula and an alternative one (eGDR-GMI) incorporating the glucose management indicator (GMI) derived from continuous glucose monitoring (CGM). We also explored the relationship between eGDR-GMI, cardiovascular risk factors, and the prevalence of diabetes-related complications. METHODS AND RESULTS: We designed a cross-sectional study that included adults with T1D. eGDR-GMI and eGDR (mg/kg/min) were calculated using GMI or HbA1c, waist circumference, and hypertensive state. Clinical data were collected from electronic medical records. The analyses encompassed 158 participants with a mean age of 39 ± 13 years. The Bland-Altman analysis showed a good agreement between eGDR-GMI and eGDR. When we divided participants in eGDR-GMI tertiles we found a higher prevalence of diabetes-related complications and a less favorable metabolic profile in the lowest eGDR-GMI tertile. The relative risk of retinopathy, nephropathy, and neuropathy significantly increased by approximately 1 unit with each decrease in eGDR-GMI, regardless of age, sex, disease duration, lipids, and smoking habit. CONCLUSIONS: eGDR-GMI represents a valid and robust alternative to the eGDR to assess insulin resistance in T1D. Low eGDR-GMI is associated with diabetes complications and a less favorable metabolic profile. Incorporating the eGDR-GMI into clinical practice can enhance the characterization of T1D people and allow for a more personalized treatment approach.

Reasons for disposal and cull cow value of Holstein cows compared with Holstein, Jersey, Montbeliarde, Normande, and Viking Red crossbred cows.

Cull cows from dairy farms in the United States account for 10% of the beef market; however, few studies have evaluated the effects of crossbreeding on reasons for disposal and cull value of dairy cows. The objective of the study was to compare reasons for disposal and cull cow value of Holstein and crossbred cows (n = 1,292) in an experimental dairy herd at the University of Minnesota West Central Research and Outreach Center, Morris, Minnesota. Cows were Holstein (n = 272), 1964 genetic control Holstein (n = 161), 3-breed crossbred cows (n = 538) composed of the Montbéliarde, Viking Red, and Holstein (MVH) breeds, and 3-breed crossbred cows (n = 321) composed of the Normande, Jersey, and Viking Red (NJV) breeds. The 1964 genetic control Holsteins cows originated from a design initiated at the University of Minnesota for comparison of the1964 Holstein and contemporary Holstein cows selected for production across time. Records spanned from January 2010 to December 2023. Reasons for disposal were recorded in PCDart Herd Management Software, and cull value and body weight were from receipts from livestock cull markets. For all cows, the primary reason for disposal was for reproduction (44.4%), mastitis (18%), other reasons (14.6%), died (10.3%), dairy purposes (8.4%), and low production (4.3%). Independent variables for statistical analysis of cull value were the fixed effects of body weight at time of culling, DIM at culling (0 to 49 DIM, 50 to 99 DIM, 100 to 149 DIM, 150 to 199 DIM, 200 to 249 DIM, 250 to 299 DIM, 300 to 350 DIM, and 350+ DIM), year (2010 to 2023), season (spring, summer, autumn, winter), parity (1, 2, 3, 4, 5+), primary reason for culling, breed group and sire breed group nested within breed group. Least squares means for bodyweight at culling was 558 kg for Holsteins, 543 kg for 1964 Holsteins, 551 kg for MVH crossbred cow, and 499 kg for NJV crossbred cows. For the analysis across time, 2014 had the highest cull value ($1,126.98) and 2020 had the lowest gross cull value ($515.21). Cows culled greater than 300 DIM had the highest cull value and cows culled less than 50 DIM had the lowest cull value. Cows culled during the spring and summer had higher cull value compared with cows culled during the autumn and winter. The Holstein cows ($730.04) had lower gross value compared with 1964 Holsteins ($804.38) cows and MVH ($767.39) cows. The NJV ($771.39) cows were not different from crossbreds sired by Montbeliarde, Viking Red, and Holstein bulls. Results for comparisons of breed group are from one experimental herd, so inferences to the wider dairy cow population should be undertaken with caution. In summary, dairy producers may receive greater cull value from crossbred cows compared with Holstein cows.

Assessing relative risks of municipal wastewater disposal options for Southeast Florida.

A comparative assessment of the risks of the three current wastewater effluent disposal options and three other potential options was conducted for Southeast Florida communities. The question was how the risk to humans from the use of potable reuse compares to the other five available wastewater disposal alternatives. The need for this type of risk assessment is due to the potential to use potable reuse as a water supply and the potential resistance from the public as a result of such a proposal. Water quality data relevant to disposal of wastewater treatment plant effluent from South Florida utilities along with water quality data on the receiving waters and drinking water standards were obtained for the project. The comparison of the public health risks associated with these disposal alternatives indicated that health risks associated with deep wells and direct potable reuse were generally lower than those of the other alternatives.

Were Needles Everywhere?: Differing Views on Syringe Waste and Disposal Associated With Needs-Based Syringe Services Programs Among Community Partners and Persons Who Inject Drugs.

BACKGROUND: Community concerns surrounding syringe waste are a common barrier to syringe services program (SSP) implementation. In Kanawha County, West Virginia, community opposition to SSPs resulted in the closure of needs-based SSPs prior to and during an HIV outbreak among persons who inject drugs (PWID). This qualitative analysis examines views of PWID and community partners on syringe waste and disposal associated with needs-based SSPs. METHODS: Qualitative interviews with 26 PWID and 45 community partners (medical and social service providers, law enforcement personnel, policymakers, and religious leaders) were conducted. Interviews were recorded, transcribed, and coded. Code summaries described participants' views on syringe waste and disposal and needs-based SSPs. RESULTS: Community partners and PWID who favored needs-based SSPs reported that needs-based SSPs had not affected or reduced syringe waste. Conversely, community partners who favored one-to-one exchange models and/or barcoded syringes described needs-based SSPs increasing syringe waste. Community partners often cited pervasive community beliefs that SSPs increased syringe waste, risk of needlesticks, drug use, and crime. Community partners were unsure how to address syringe waste concerns and emphasized that contradictory views on syringe waste posed barriers to discussing and implementing SSPs. CONCLUSIONS: Participants' views on whether syringe waste was associated with needs-based SSPs often aligned with their support or opposition for needs-based SSPs. These differing views resulted in challenges finding common ground to discuss SSP operations amid an HIV outbreak among PWID. SSPs might consider addressing syringe waste concerns by expanding syringe disposal efforts and implementing community engagement and stigma reduction activities.

The environmental impact of hip and knee arthroplasty: An analysis of carbon emissions and disposal costs.

BACKGROUND AND PURPOSE: The rise in hip and knee arthroplasty for osteoarthritis requires addressing healthcare system pollution to support Ireland's climate change goals. This research aimed to quantify waste generated and determine environmental and economic impacts to promote sustainable strategies in joint arthroplasty and shed light on the suboptimal waste management practices. METHODS: The study was conducted at National Orthopaedic Hospital Cappagh (NOHC), measuring waste generated during hip and knee arthroplasty. Clinical, domestic, and recycled waste weights were recorded, including the segregation of Central Sterile Supply Department (CSSD) Blue Wrap waste in ten operations. Kilograms of carbon dioxide emissions (kgCO2e) and disposal costs were calculated. RESULTS: In a sample of 100 joint arthroplasty operations, the study found that revision knees produced 23.58 â€‹kgCO2e per case, revision hips 23.50 â€‹kgCO2e, primary knees 15.82 â€‹kgCO2e, and primary hips 14.64 â€‹kgCO2e. CSSD Blue Wrap contributed on average 13.5% of OT waste. Extrapolating these findings to the estimated number of joint arthroplasties performed in 2022 â€‹at NOHC (1556 hip and knee joint arthroplasties), the emissions were estimated to be 24,576 kgCO2e, with the cost of disposal up to €29,228. Strategies to mitigate this waste have been identified and proposed. CONCLUSION: The research aimed to address the environmental impact of orthopaedic joint arthroplasties, offering strategies to reduce waste generation, carbon emissions, and cost. Utilising our methodology to calculate greenhouse gas emissions will empower sustainability offices to conduct their own waste audits and implementing our strategies for waste management practices can help minimise environmental waste.

Engineering properties optimization of dispersive soil by calcium silicate waste-The role of steel-making slag.

Steel slag (SS) is a byproduct that comes from the production of crude steel in alkaline oxidation furnaces. Resource utilization of steel slag, a calcium-silicon solid waste, is an urgent problem. This paper investigates a solid waste disposal method that applies different steel slag contents to modify dispersive soil. The engineering properties and modification mechanisms of dispersive soil specimens are studied and revealed by performing microstructure, mineral evolution, unconfined compressive strength (UCS), and tensile strength analysis. The pinhole test, mud ball crumb test (BCT), and mud cube crumb test (CCT) were carried out to determine the dispersivity of the soil specimens. Results show that when the steel slag content increases from 1% to 10%, the unconfined compressive strength and tensile strength increase by 176.05% and 75.40%, respectively. For soil specimens without curing time under 50 mm water head, the weight loss of the specimen with 10% steel slag content decreases by 72.03% compared to specimens with 1% steel slag content. Microstructural and mineralogical analyses indicate that the hydration reaction of steel slag changes the ionic composition of the soil and generates reaction products with effects such as filling and connection. To sum up, steel slag effectively improves water stability and mechanical properties of dispersive soil.

An overview of waste management practices of street vendors in sub-saharan africa: A meta-analysis.

Many low-income developing countries struggle with waste collection and the development of disposal facilities, leading to issues such as illegal dumping and poor enforcement of waste management regulations. The pollution caused by street vendors' waste is particularly evident in the central business districts of cities in developing nations. The informal economy, which includes activities such as street vending has become prevalent in developing countries, particularly in Sub-Saharan African (SSA) nations. This study aims to conduct a systematic review and meta-analysis of existing literature on street vendors' waste management practices in the region, with a focus on understanding the factors influencing waste mismanagement and identifying integrated strategies employed across SSA. In most SSA areas, research is conducted to evaluate food vendor hygienic practices (33%), however the waste management component, which is crucial to hygiene, makes up just 15%, which is twice as small as the research that focused on hygienic practices. As a result, street vendors in the majority of sub-Saharan nations have little interest in waste management procedures. Many street vendors in the region resort to informal waste disposal methods because of no access to formal waste management infrastructure since they are not recognised as formal businesses. The study acknowledges the street vendors' contribution to food security in developing Sub Saharan Africa, as well as the significance of comprehending their waste management practices. Despite their prevalence in urban areas, these informal businesses still face a lack of recognition and inclusion from governing bodies. Therefore, the study emphasises the necessity of incorporating street vendors into formal municipal waste management systems and providing them with enhanced infrastructure and services. Given that the lack of recognition subsequently make it challenging to integrate vendors into formal waste management systems. Subsequently this has a negative cumulative impact on developing and enforcing clear regulations that specify the responsibilities of street vendors in waste management. Thus, leading to the absence of comprehensive by laws regulations governing waste management for street vendors within Sub-Saharan Africa.

A systematic comparison of salt removal efficiency in washing treatment by using fly ashes from 13 MSWI plants in China.

Municipal solid waste incineration (MSWI) fly ash contains large amounts of Ca, Si, and other elements, giving it the potential to be used as a raw material for cement production. However, fly ash often contains a high content of salts, which greatly limits its blending ratio during cement production. These salts are commonly removed via water washing, but this process is affected by the nature and characteristics of fly ash. To clarify the influence of the ash characteristics on salt removal, a total of 60 fly ash samples from 13 incineration plants were collected, characterized, and washed. The ash characterization and cluster analysis showed that the incinerator type and flue gas purification technology/process significantly influenced the ash characteristics. Washing removed a high percentage of salts from fly ash, but the removal efficiencies varied significantly from each other, with the chlorine removal efficiency ranging from 73.76% to 96.48%, while the sulfate removal efficiency ranged from 6.92% to 51.47%. Significance analysis further revealed that the salt removal efficiency varied not only between the ash samples from different incinerators, but also between samples collected at different times from the same incinerator. The high variance of the 60 ash samples during salt removal was primarily ascribed to their different mineralogical and chemical characteristics. Mineralogical analysis of the raw and washed ash samples showed that the mineralogical forms and proportion of these salts in each ash sample greatly influenced their removal. The presence of less-soluble and insoluble chloride salts (e.g., CaClOH, Ca2Al(OH)6(H2O)2Cl etc.) in fly ash significantly affected the chlorine removal efficiency. This study also found that Fe, Mn, and Al in fly ash were negatively correlated with the dechlorination efficiency of fly ash. In summary, the different physical and chemical properties of fly ash caused great discrepancies in salt removal. Consequently, it is suggested to consider the potential impact of the ash source and ash generation time on salt removal to ensure a reliable treatment efficiency for engineering applications.

Identifying ESG types of Chinese solid waste disposal companies based on machine learning methods.

In the context of China's efforts to combat climate change and promote sustainable development, the solid waste treatment industry's environmental, social, and corporate governance (ESG) performance is receiving significant attention. To comprehensively assess the ESG performance of the solid waste treatment industry and identify company types, this study constructs a targeted ESG evaluation index system based on existing literature, SASB industry standards, and company reports and utilizes a random forest approach combined with K-means clustering to determine indicator weights. Based on this index system, the paper evaluates the ESG performance of 71 solid waste disposal companies (SWDCs) from 2013 to 2021 and identifies their ESG types from static and dynamic perspectives. In the static view, company types are determined based on annual ESG performance, while the dynamic view considers time-series changes to observe the evolution of company ESG types. The results show that the overall ESG performance of SWDCs falls within the 2-8-point range, indicating a noticeable high-low imbalance. Key initiatives to improve ESG performance in this industry include enhancing waste management measures, developing emergency plans, and reinforcing ESG disclosure. From a static perspective, this paper can identify companies into three categories: delayed development, single-wheel-driven, and coordinated development. Finally, from a dynamic perspective considering the time factor, companies are further subdivided into five types: continual leading, growth catch-up, slow progress, fluctuating change, and retrogressive inertia. This study not only provides targeted recommendations for different types of ESG companies but also helps various sectors of society better understand the ESG conditions of this high environmental risk industry, thereby enhancing the regulation and support for its sustainable development.

Designing low-carbon fly ash based geopolymer with red mud and blast furnace slag wastes: Performance, microstructure and mechanism.

In order to tackle the environmental problems induced by Portland cement production and industrial solid wastes landfilling, this study aims to develop novel ternary cementless fly ash-based geopolymer by recycling red mud and blast furnace slag industrial solid wastes. The fresh-state properties, mechanical strength, water permeability, phase assemblage and microstructure were systematically investigated to evaluate the performance variation and reveal the hydration mechanism for geopolymers with different mixing proportions. The results showed that a higher slag content or a lower red mud content could result in the higher fluidity and shorter setting time for fresh mixture. The existence of slag promoted the transformation of N-A-S-H to C-A-S-H gel, which contributed to higher compressive strength and better resistance to water penetration. However, an excessive incorporation of 30% red mud may impede the generation of N-A-S-H gel and form more flocculent-like loose hydrates, thus to mildly degrade the mechanical strength and anti-permeability. The synergetic utilization of red much and blast furnace slag in fly ash-based geopolymer led to much less CO2 emission compared with the condition that red much or slag was singly added, which demonstrated prominent environmental advantages for such kind of ternary cementless geopolymer with equivalent mechanical strength.

Preparation of functional geopolymers from municipal solid waste incineration fly ash: An approach combining experimental and computational simulation studies.

This study aims to evaluate the feasibility and safety of using municipal solid waste incineration fly ash (MSW-IFA) in the development of geopolymer-based solidification/stabilization (S/S) treatments. Geopolymers have garnered attention as a sustainable alternative to traditional cement, owing to their high strength, stability, and minimal CO2 emissions. In this study, a combination of experimental and simulation calculations was used to investigate the setting time, mechanical properties, environmental risks, hydration mechanisms and processes of municipal solid waste incineration fly ash-based polymeric functional cementitious materials (GFCM). The results demonstrate that the mechanical properties of GFCM are related to the changes in the mineral phases and the degree of compactness. Quantum chemical calculations indicate that the hydration products may be [Si(OH)4], [Al(OH)3(OH2)] and [Al(OH)4]-. It is possible that the heavy metals are embedded in the hydrated silica-aluminate by electrostatic interaction or chemisorption. Heavy metals may be embedded in hydrated silica-aluminate by electrostatic action or chemisorption. This study provides a feasible method for resource utilization and heavy metal stabilization mechanism of MSW-IFA.

Kaolin-Derived Porous Silico-Aluminate Nanoparticles as Absorbents for Emergency Disposal of Toluene Leakage.

To rapidly eliminate toluene from aqueous environments during leakage accidents, this paper synthesized porous silico-aluminate nanoparticles (SANs) via a hydrothermal method, using cost-effective and non-toxic natural kaolin as the basic raw material. The morphology and structure of the porous SANs were characterized using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and BET-specific surface area tests. The effects of different conditions, such as the dosage of porous SANs, initial concentration of toluene, temperature, capture time, and pH, on the adsorption performance of porous SANs were analyzed. The as-prepared SANs exhibited a high removal efficiency and rapid adsorption performance toward toluene in aqueous solution. Finally, the kinetics of the adsorption of toluene in aqueous solution by porous SANs were investigated. The mechanism of the adsorption of toluene by porous SANs was further discussed. These findings provide a cost-effective and highly efficient absorbent for the emergency disposal of toluene leakage accidents.