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Relay strip intercropping of soybeans and maize achieves high net ecosystem economic benefits by boosting land output and alleviating greenhouse gas emissions.

Cereal-legume intercropping provides a solution for achieving global food security, but the mechanism of greenhouse gas emissions and net ecosystem economic benefits of maize-soybean relay intercropping are poorly understood. Hence, we conducted a two-factor experiment to investigate the effects of cropping systems, containing maize-soybean relay intercropping (IMS), monoculture maize (M) and monoculture soybean (S), as well as three nitrogen levels at 0 (N0), 180 (N1), 240 (N2) kg N ha-1 on crop grain yield, greenhouse gas emissions, soil carbon stock and net ecosystem economic benefit (NEEB). The average grain yield of IMS (7.7 t ha-1) increased by 28.5% and 242.4% compared with M (6.0 t ha-1) and S (2.2 t ha-1). The land equivalent ratio (LER) of IMS was 2.0, which was mainly contributed by maize (partial LER: 1.2) rather than soybean (partial LER: 0.8). Although the total grain yield of IMS remarkably enhanced by 43.6% and 45.5% in N1 and N2 contrast in N0, the LER was 37.5% and 38.6% lower in N1 and N2 than in N0. The net global warming potential (GWP) of maize and soybean was 11.6% and 1.8% lower in IMS than in the corresponding monoculture, which resulted from a decline in GWP and enhanced soil organic carbon stock rate. Moreover, NEEB was 133.5% higher in IMS (14 032.0 Chinese yuan per year) than in M, mainly resulting from an increase in total economic gains and a decline in GWP cost. A more robust response in yield gain rather than total costs to N inputs of IMS led to 46.8% and 48.3% higher NEEB in N1 and N2 than in N0. Maize-soybean relay intercropping with 180 kg N ha-1 application can obtain yield advantages without raising environmental costs, which provides an approach to achieving sustainable agricultural production. © 2024 Society of Chemical Industry.

Blue Carbon Assessment in the Salt Marshes of the Venice Lagoon: Dimensions, Variability and Influence of Storm‐Surge Regulation

AbstractSalt marshes are intertidal coastal ecosystems shaped by complex feedbacks between hydrodynamic, morphological, and biological processes. These crucial yet endangered environments provide a diverse range of ecosystem services but are globally subjected to high anthropogenic pressures, while being severely exposed to climate change impacts. The importance of salt marshes as “blue carbon” sinks, deriving from their primary production coupled with rapid surface accretion, has been increasingly recognized within the framework of climate mitigation strategies. However, large uncertainties remain in salt marsh carbon stock and sequestration estimation. In order to provide further knowledge in salt marsh carbon assessment and investigate marsh carbon pool response to management actions, we analyzed organic matter content in salt marsh soils of the Venice Lagoon (Italy) from 60 sediment cores to the depth of 1 m and estimated organic carbon stock and accumulation rates in different areas. Organic carbon stocks and accumulation rates were highly variable in different marshes, being affected by organic and inorganic inputs and preservation conditions. Our estimates suggest that the studied marshes store 17,108 ± 5,757 tons of carbon per square kilometer in top 1‐m of soil and can accumulate 85 ± 25 tons of carbon per square kilometer per year. However, flood regulation may reduce the annual marsh CO2 sequestration potential by more than 30%. Our results contribute valuable information for regional carbon assessments, reinforcing the need for integrated coastal management policies to preserve the ecosystem services of coastal environments, and underscore the importance of considering local variability and methodological variations.

Temporal patterns and regional comparisons of recruitment rates of United States fish stocks

Temporal patterns and regional comparisons of recruitment rates of United States fish stocks

Effects of wariness on economic growth in overlapping generations models

We introduce the notion of wariness, defined as a concern for the lowest lifetime utility, in overlapping generations models and explore its effects on economic growth. In an exogenous growth model, under standard assumptions, we prove that the capital stock converges to a steady state. We then explore conditions under which this steady state is increasing (or decreasing) in the wariness level. We also provide a necessary and sufficient condition for the dynamic efficiency of the intertemporal equilibrium. In endogenous growth models (à la Romer (1986) or à la Barro (1990)), we show that the growth rate of capital stock per capita in the economy with wariness is lower (higher, respectively) than that in the economy without wariness if and only if the capital return is high (low, respectively).

Spillover Effects between Oil, Gold, Stock, and Exchange Rate Returns in Thailand: An Extended Joint Connected TVP-VAR Approach

The objective of this study is to analyze the spillover effects among the returns of oil, gold, the stock market, and exchange rates in Thailand. Using the time-varying parameter vector autoregression model (TVP-VAR) with extended joint connectedness and data from April 2002 to March 2024, our analysis reveals a moderate level of the dynamic linkage among these returns. We observe that the dynamic connectedness among all returns varies over time, influenced by global economic events and country situations. Notably, in Thailand's landscape, stock market and gold returns act as net shock transmitters, with the stock market exhibiting the highest volatility among all variables, while oil and exchange rate markets function as net recipients. These insights significantly contribute to understanding asset and commodity markets and offer valuable policy implications for effectively managing these markets.

Investigating the Promising P28 Peptide-Loaded Chitosan/Ceramic Bone Scaffolds for Bone Regeneration.

Bone has the ability to heal itself; however, bone defects fail to heal once the damage exceeds a critical size. Bone regeneration remains a significant clinical challenge, with autograft considered the ideal bone graft material due to its sufficient porosity, osteogenic cells, and biological growth factors. However, limitations to bone grafting, such as limited bone stock and high resorption rates, have led to a great deal of research into developing bone graft substitutes. The P28 peptide is a small molecule bioactive biomimetic alternative to mimic the bone morphogenetic protein 2 (BMP-2). In this study, we investigated the potential of P28-loaded hybrid scaffolds to mimic the natural bone structure for enhancing the bone regeneration process. We hypothesized that the peptide-loaded scaffolds and nude scaffolds both have the potential to promote bone healing, and the bone healing process is accelerated by the release of the peptide. To verify our hypothesis, C2C12 cells were evaluated for the presence of calcium deposits by histological stain at 7 and 14 days in cultures with hybrid scaffolds. Total RNA was isolated from C2C12 cells cultured with hybrid scaffolds for 7 and 14 days to assess osteoblast differentiation. The project findings demonstrated that the hybrid scaffold could enhance osteoblast differentiation and significantly improve the therapeutic effects of the scaffold in bone regeneration.

Co-movements between Stock Markets and Exchange Rates: Empirical Evidence from the G20 Nations

This study investigates the relationship between stock markets and exchange rate markets in the short and long run for G20 countries by analyzing weekly stock market returns and exchange rates from January 2008 to March 2023. This study uses the CD test for testing cross-sectional dependence in all the panel series, and unit root tests are employed to verify the stationarity properties of variables. Based on the above results, the panel ARDL model and PMG estimator are used to establish the long-run and short-run cointegrating relation between the stock and exchange rate markets. We have found a stable positive relationship between the stock markets and the exchange rate of G20 countries in the long run, but a negative association was found in the short run. These findings highlight the intricate dynamics between stock markets and exchange rates and the interconnectedness of G20 nations. The robust positive long-term correlation and the short-term negative association exhibit the differential impacts of macroeconomic variables over varying time horizons

A Heuristic for Fat-Tailed Stock Market Returns

Large negative stock and equity portfolio rates of return occur more frequently than they should under the Gaussian normal distribution. They tend to be kurtotic, roughly as if they were drawn from Student T-distributions with 2 to 5 degrees of freedom. A very easy adjustment to help assess the probability of losses is to work with a transformed Z score, Z ′ = − 1.25 − log ( − Z ) . For example, one should expect a stock return that is 17 standard deviations below the mean under the empirical distribution as often as one would expect to see a draw that is Z ′ = | – 1.25 − log ( 17 ) ≈ − 4 | standard deviations below the mean under the idealized normal distribution.

On testing the changes in trends of stock market index and rates

Calibration of interest rate models benefits from grouping data to homogenous classes. Such an approach is typical in many financial time series. Preliminaries have been developed for Cox–Ingersoll–Ross models but this issue remains an open problem for many more realistic interest rate models. Here we develop such a strategy for general class interest rate and classes are based on p-value thresholds for testing for normality and gamma distributions. We use as the benchmark financial series of Chilean stock market index IPSA (Indice de precios selectivo de acciones) and its log-returns. We also study the relationship between interest rate and the market returns represented by the IPSA indicator, with positive correlation in some lags which reveals some interesting facts in the contrary to the conventional theory.

Evaluation of Macroeconomic Influences on Company Stock Prices in the Jakarta Islamic Index (JII): Analysis of Inflation, Exchange Rates, and Money Supply (2020-2023)

The research is intended to examine the impact of the independent variables, namely inflation, exchange rates, and total money in circulation, on the stock rates of companies listed on the Jakarta Islamic Index (JII). Using a quantitative approach and purposive sampling method, the study cited a sample of 16 companies that were consistently listed on the JII from January 2020 to December 2023. Data analysis was carried out using panel information analysis with the help of the Eviews12 application. The research confirmed that inflation and money supply have a significant favorable impact on stock prices, through respective coefficients of 0.087409 and 0.751782. In contrast, the exchange rate has a significant adverse impact on the stock rate, through a coefficient of -1.646472. The simultaneous F-test confirms that all three variables together have a significant impact on the stock rate.

Assessment of soil fraction, carbon storage capacity, and rate of carbon uptake from three coastal ecosystems: Mangroves, seagrass, and mudflats in Benoa Bay, Indonesia

Abstract. Dharmayasa IGNP, Sugiana IP, Putri PYA, Boonyasana K. 2024. Assessment of soil fraction, carbon storage capacity, and rate of carbon uptake from three coastal ecosystems: Mangroves, seagrass, and mudflats in Benoa Bay, Indonesia. Biodiversitas 25: 2541-2549. Coastal habitats, known as blue carbon ecosystems, are highly productive at absorbing and storing carbon. Most carbon is stored as soil organic carbon, and its quantity can vary depending on various factors, including the presence of plants such as mangroves and seagrass, and environmental conditions, including soil fraction. This study quantifies soil carbon stored and its burial rate in three primary coastal ecosystems: mangroves, seagrasses, and mudflats. The ashing method (loss on ignition) is used to quantify carbon content, which is then converted into soil carbon storage and burial rate. Gravimetry and the settling time method are used to determine the soil fraction. We also measure the soil and water properties directly during the sampling time. This study revealed significant soil carbon stock and burial rate variations across different ecosystems. The order of ecosystems with the most extensive carbon stock and burial rate is as follows: mangrove (69-145 tC ha-1 and 1.6-3.4 tCha-1yr-1)>seagrass (63-75 tC ha-1 and 1.5-1.7 tCha-1yr-1)>mudflat (49-61 tC ha-1 and 1.2-1.4 tCha-1yr-1). Mangroves with natural growth have a higher carbon storage capacity than rehabilitated ones. Soil carbon content is highly correlated with the soil and water pH, Dissolved Oxygen (DO), water content, bulk density, and soil type. The findings demonstrate that carbon absorption capability varies among coastal habitats, with vegetated environments exhibiting higher carbon storage levels. Converting land, particularly mudflats, into seagrass beds or mangrove forests may maximize the efficiency of coastal ecosystems as carbon sinks. However, it should be noted that these findings are only estimates, and the precise measurement numbers may differ due to seasonal circumstances or reclamation activities, which might cause oscillations in sedimentation rates. These variations, in turn, could affect the levels of carbon stored and the speed at which it is buried.

Enhancing productivity and sustainability of ravine lands through horti-silviculture and soil moisture conservation: A pathway to land degradation neutrality

Ravine lands are the worst type of land degradation affecting soil quality and biodiversity. Crop production in such lands is impossible without adopting proper conservation measures. In-situ moisture conservation techniques could play an instrumental role in restoring ravine lands by improving soil moisture. We hypothesized that restoring ravine land through a combination of tree planting, fruit crop cultivation, and in-situ moisture conservation practice would result in significant improvements in productivity, profitability, and soil fertility. An experiment was conducted involving the combination of Malabar Neem (Melia dubia) and Dragon fruit (Hylocereus undatus) in conjunction with in-situ soil moisture conservation measures specifically involving half-moon structures (HM). The experiment was conducted under randomized block design (RBD) comprising eight treatments. These treatments include sole Melia cultivation (MD 3m × 3m), sole cultivation of dragon fruit (DF 3m × 3m), silviculture system (MDF-3m × 3m), horti-silviculture system with larger spacing (MDF-4m × 4m), sole Melia cultivation with in-situ moisture conservation (MDH-3m × 3m), sole Dragon fruit cultivation with in-situ moisture conservation (DFH-3m × 3m), horti-silviculture system of Melia and Dragon fruit with in-situ moisture conservation (MDFH-3m × 3m), and horti-silviculture system with larger spacing and in-situ moisture conservation (MDFH-4m × 4m). Each treatment was replicated thrice to evaluate their impact on productivity, profitability, soil fertility, and carbon sequestration for 8 years (2016–2023). The results revealed that the horti-silviculture system (MDFH-3 × 3 m) exhibited the highest total tree biomass and total carbon sequestration with an increase of 183.2% and 82.8% respectively, compared to sole Melia cultivation without HM and sole Melia with HM. Furthermore, sole Melia with HM augmented soil nutrients (N, P, K, and SOC) by 74.4%, 66.4%, 35.2%, and 78.3%, respectively, compared to control (no planting), with performance at par with MDFH-3 × 3 m. Similarly, sole Melia with HM enhanced SOC stock and SOC sequestration rate by 79.2% and 248% over control. However, it was found at par with MDFH-3 × 3 m. The horti-silviculture system (MDFH-3 × 3 m) consistently produced the highest fruit yield throughout the years surpassing other treatments. This treatment increased the average dragon fruit yield by 115.3% compared to sole dragon fruit without HM. Hence, the adoption of the horti-silviculture system (MDFH-3 × 3 m) could be a promising strategy for achieving enhanced environmental and economic benefits in ravine lands. Therefore, dragon fruit based horti-silviculture system (MDFH-3 × 3 m) could be recommended for restoration of ravine lands, improving land productivity, and mitigating impact of soil erosion particularly in Western India or similar agro-climatic regions of the world.

A Two-Stage Analysis of Interaction Between Stock and Exchange Rate Markets: Evidence from Turkey

A Two-Stage Analysis of Interaction Between Stock and Exchange Rate Markets: Evidence from Turkey

Support vector machine-based stock market prediction using long short-term memory and convolutional neural network with aquila circle inspired optimization

ABSTRACT Predicting the stock market is one of the significant chores and has a successful prediction of stock rates, and it helps in making correct decisions. The prediction of the stock market is the main challenge due to blaring, chaotic data as well as non-stationary data. In this research, the support vector machine (SVM) is devised for performing an effective stock market prediction. At first, the input time series data is considered and the pre-processing of data is done by employing a standard scalar. Then, the time intrinsic features are extracted and the suitable features are selected in the feature selection stage by eliminating other features using recursive feature elimination. Afterwards, the Long Short-Term Memory (LSTM) based prediction is done, wherein LSTM is trained to employ Aquila circle-inspired optimization (ACIO) that is newly introduced by merging Aquila optimizer (AO) with circle-inspired optimization algorithm (CIOA). On the other hand, delay-based matrix formation is conducted by considering input time series data. After that, convolutional neural network (CNN)-based prediction is performed, where CNN is tuned by the same ACIO. Finally, stock market prediction is executed utilizing SVM by fusing the predicted outputs attained from LSTM-based prediction and CNN-based prediction. Furthermore, the SVM attains better outcomes of minimum mean absolute percentage error; (MAPE) and normalized root-mean-square error (RMSE) with values about 0.378 and 0.294.

An Explanatory Model for the Impact of Investor Sentiment on Stock Markets Integrating XGBoost and SHAP

With the widespread popularity of Internet, non-professional individual investors can share information and express their tendency through online forum, exerting a certain influence on the price fluctuations in the stock market. This study has compiled investor sentiment data from the stock forum of Eastmoney.com for the years 2018 to 2022. By integrating this data with the daily return rates of individual stocks in the Shanghai Stock Exchange (SSE), an XGBoost regression model has been established. Utilizing SHAP (Shapley Additive exPlanations) for visualization and analysis, the findings reveal that the daily stock returns exhibit a significant positive correlation with investor positive sentiment and turnover rate, and a significant negative correlation with the number of forum posts. Conversely, there is no significant correlation with metrics such as average number of followers, average reading volume, average number of likes, average net comments, user average influence index, and emotional consistency index within the stock forum. Moreover, in the Chinese SSE market, stocks of different market capitalizations do not display significant differences in sensitivity to investor sentiment. This study contributes novel perspectives and methodologies to the study of investor sentiment, aiding in a more profound comprehension of the behaviors of individual investors participating in stock forum discussions and the consequential impact of such behaviors on the market.

High-Resolution Mapping of Urban Residential Building Stock Using Multisource Geographic Data

The rapid pace of urbanization and the increasing concentration of populations in urban areas have generated a substantial demand for architectural structures, resulting in a significant increase in building stock and continuous material flows that interact with the environment. This study emphasizes the importance of high-spatial-resolution mapping of residential building stock for effective urban-construction resource management, planning, and waste management. Focusing on Xi’an as a case study, the research develops a comprehensive framework for mapping urban residential building stock by integrating diverse data dimensions, including temporal, spatial, network, and multi-attribute aspects. The findings indicate that between 1990 and 2020, approximately 4758 residential communities were established in central Xi’an. The analysis of seven key residential construction materials revealed that the building stock escalated from 1.53 million tons to 731.12 million tons, with a steady spatial expansion of material distribution. The study attributes this growth to factors such as population increase, economic advancement, and policy initiatives, which, in turn, have driven the demand for residential building materials and reinforced the interdependence between urban expansion and residential construction development. Remarkably, from 1990 to 2020, the population surged by 2.1-fold, the economy by 66-fold, and the stock of residential building materials by 477-fold, indicating that the growth rate of material stock consistently outpaced that of both population and economic growth. Over the past three decades, the rapid expansion of residential buildings has led to the encroachment of urban ecological spaces by concrete structures. The methodology proposed in this study for quantifying building material offers valuable insights for policymakers and urban and environmental planners to foster responsible resource consumption and supports component-level circularity in the built environment.

Comparative Assessment of Inorganic Fertilizer and Farm Yard Manure Application on Yield, Sustainable Yield Index and Soil Physico-Chemical Properties in Cauliflower-Capsicum Cropping Sequence in Northern- Western Himalayas

ABSTRACT Continuous addition of inorganic fertilizer and farm yard manure (FYM) alone or in combination is necessary to assess the changes in yield and soil properties. Therefore, a study was conducted for consecutive two years on nutrient management with nine treatments viz. T1- control, T2-100% FYM (N equivalent basis), T3-100% N, T4-NP, T5-NK, T6-PK, T7-NPK, T8-100% NPK+ FYM (recommended Practice) and T9- 150% NPK+ FYM to assess the influence of different treatments on yield, sustainable yield index, soil physic-chemical properties and soil carbon stock and sequestration rate in cauliflower and capsicum cropping sequence. Results showed that the addition of farm yard manure alone or in a combination with chemical fertilizers contributed to higher soil organic stock and soil carbon sequestration rate. Application of 150% NPK + FYM improved the SYI of system by 49.4% over a control. This treatment increases soil carbon stock by 12.5% from 25.9 Mg ha−1 to 29.6 Mg ha−1 and recorded with maximum soil carbon sequestration rate, i.e. 2.21 Mg C m−3 year−1 over the 2 years. Thus, balanced fertilization of NPK and FYM is beneficial for the maintenance of soil physical health, improving CEC and macro and micronutrient levels.

Does asset-based uncertainty drive asymmetric return connectedness across regional ESG markets?

This paper investigates the impact of asset-based uncertainty on the asymmetric return connectedness and hedging effectiveness of regional environmental, social and governance (ESG) equity markets from January 2017 to December 2022. The results of the asymmetric time-varying parameter vector autoregressive connectedness approach show strong dynamic connectedness within regional ESG markets, with the dominance of negative returns intensifying during COVID-19. Quantile regressions reveal that uncertainty in crude oil and bond markets negatively affects asymmetric return connectedness across bearish, normal and bullish market periods, whereas uncertainty in stock, gold and exchange rate markets has a positive impact. Overall, asset-based uncertainty influences negative return connectedness more than positive return connectedness, and a varied influence of asset-based uncertainty is noted during COVID-19 and the Russia–Ukraine war. A portfolio analysis shows that all ESG markets significantly contribute to higher hedging effectiveness, with a portfolio constructed based on the minimum connectedness approach outperforming the other portfolios. The findings provide policy implications for portfolio and risk management strategies.

Impact of the COVID-19 Pandemic on Blood Lead Testing in Children in the United States.

The study objective was to evaluate the impact of the coronavirus disease (COVID-19) pandemic on pediatric blood lead testing in the United States. Clinical laboratory pediatric (ages <6 years) blood lead level (BLL) tests performed by Quest Diagnostics, January 2019-March 2022, were analyzed. Patients were categorized by age, by sex, and, through matching by ZIP code with US Census data, for race, ethnicity, pre-1950 housing, and poverty estimates. Over 2.8 million results from children (<6 years old) from all 50 states and the District of Columbia were included. Compared to March-May 2019, BLL testing was lower by 53.6% in March-May 2020 and lower by 14.6% in March-May 2021. Testing rebounded more for children in predominantly White non-Hispanic communities and among children living in communities, based on ZIP codes, with the least pre-1950 housing stock and lowest poverty rates. The proportion of children with BLL at or above the United States Centers for Disease Control and Prevention reference values of 3.5 and 5.0 µg/dL fell by 19% and 24%, respectively, in 2021 versus 2019. In conclusion, pediatric BLL testing has rebounded from sharp declines during the early pandemic period but unevenly. Declines in the proportion of children with elevated BLL should be interpreted with caution, as testing rebounds were less robust among communities with the highest risk of lead poisoning, notably communities with the oldest housing stock and higher poverty rates. More public health efforts are needed to address lead toxicity throughout the United States, especially in communities that did not experience a full rebound subsequent to the early COVID-19 pandemic period.

An Inventory Model for Perishable Items with Cubic Deterioration Rate Having Shelf-Life Price, Stock, and Time-Dependent Demand Rate

An Inventory Model for Perishable Items with Cubic Deterioration Rate Having Shelf-Life Price, Stock, and Time-Dependent Demand Rate