Temporal Stability of Recreation Choices

We evaluate the stability of coefficient and willingness to pay (WTP) estimates for recreation services over two time periods. To address this question, we estimate a Random Utility Maximization (RUM) model of recreation demand, using two datasets from different time periods, but concerning the same study area. We then compare the estimation results and evaluate the temporal stability of preferences that drive recreation choices. The two datasets are on trips made by Delaware residents to beaches in the Mid-Atlantic region: Delaware, New Jersey, Maryland and Northern Virginia. The first dataset was collected using a mail survey in 1997 and the second dataset was gathered through an Internet survey in 2005. Besides the time periods, and the survey methods, there are also significant sample size differences between the two datasets. In the 1997 sample, 400 Delaware residents made at least one day trip, while in the 2005 dataset, only 50 Delawareans visited the beaches of interest.recreation demand, nonmarket valuation, Environmental Economics and Policy, Q51, Q26,

Combustion behaviour of some biodesulphurized coals assessed by TGA/DTA

Thermal analysis, i.e. TGA/DTA is used to study the changes in the combustion behaviour of microbially treated coals. In view of their high sulphur content and industrial significance three samples are under consideration, i.e. one lignite and two subbituminous from different region in Bulgaria. The differences in burning profiles can be related to structural changes resulted from biological treatments. The overall biological treatment generates these changes probably due to the oxidation process. Concerning organic sulphur biodesulphurization there is no change in any drastic mannerof the thermal characteristic parameters. In general, applied biotreatments provoke a complex influence on combustion coal behaviour. From one side a better ignition performance, a minor decrease in higher heating value and diminishing peak temperature of maximum weight loss rate for all biotreated samples are observed. From other side some decrease in the combustibility indicated by an increase in the combustion time and the end of combustion temperature are obvious. Also well determined decrease of self-heating temperature after biotreatments evolves high risk of spontaneous unmanageable coal combustion

Combustion behaviour of some biodesulphurized coals assessed by TGA/DTA

Thermal analysis, i.e. TGA/DTA is used to study the changes in the combustion behaviour of microbially treated coals. In view of their high sulphur content and industrial significance three samples are under consideration, i.e. one lignite and two subbituminous from different region in Bulgaria. The differences in burning profiles can be related to structural changes resulted from biological treatments. The overall biological treatment generates these changes probably due to the oxidation process. Concerning organic sulphur biodesulphurization there is no change in any drastic mannerof the thermal characteristic parameters. In general, applied biotreatments provoke a complex influence on combustion coal behaviour. From one side a better ignition performance, a minor decrease in higher heating value and diminishing peak temperature of maximum weight loss rate for all biotreated samples are observed. From other side some decrease in the combustibility indicated by an increase in the combustion time and the end of combustion temperature are obvious. Also well determined decrease of self-heating temperature after biotreatments evolves high risk of spontaneous unmanageable coal combustion

Use of spike moisture content to define physiological maturity and quantify progress through grain development in wheat and barley

A single measurement is useful for determining how far a crop has progressed through grain development, and whether it has reached physiological maturity. Grain development is commonly assessed by using subjective, qualitative methods that describe the look and feel of the kernel or the colour of the straw. Physiological maturity in cereal crops can be determined more accurately by the grain moisture content; however, the moisture content of whole spikes is potentially quicker and easier to assess than that of individual kernels, and with a greater degree of accuracy. This experiment aimed to characterise the moisture dynamics of whole intact wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) spikes during the grain development phase and identify the spike moisture content corresponding to physiological maturity for both species. The dry matter and water contents of whole spikes of five wheat and five barley cultivars sown over six dates were determined at weekly intervals throughout the period of grain development from anthesis to harvest ripeness. Use of regression analysis determined that the spike moisture content at physiological maturity was 43% (95% confidence interval 41–45%) for wheat and 50% (95% confidence interval 49–51%) for barley, irrespective of differences in cultivar morphology, phenology and growing conditions. We demonstrate that progression through kernel development in wheat and barley can be assessed objectively and quantitatively by using spike moisture content, and we provide guidelines for accurate determination of the grain development stage using spike moisture

Dynamic correlation or tail dependence hedging for portfolio selection

In this paper we solve for the optimal portfolio allocation in a dynamic setting, where both conditional correlation and dependence between extremes are considered. We demonstrate that there are substantial economic costs for investors in disregarding either the dynamics of conditional correlation or the clustering of extreme events. The welfare loss increases dramatically with the investment horizon, during bad economic and market conditions, and for low levels of the agent’s relative risk aversion. We illustrate that both correlation hedging demands and intertemporal hedges due to increased tail dependence have distinct portfolio implications and they cannot act as substitutes to each other. There is a substantial utility loss for disregarding dependence between extreme realizations, even when dynamic conditional correlation has already been accounted for, and vice versa. Our results are robust to the sample period, the choice of the dependence structure, and both varying levels of average correlation and tail dependence coefficients

Biodesulphurized subbituminous coal by different fungi and bacteria studied by reductive pyrolysis. Part 1: Initial coal

One of the perspective methods for clean solid fuels production is biodesulphurization. In order to increase the effect of this approach it is necessary to apply the advantages of more informative analytical techniques. Atmospheric pressure temperature programming reduction (AP-TPR) coupled with different detection systems gave us ground to attain more satisfactory explanation of the effects of biodesulphurization on the treated solid products. Subbituminous high sulphur coal from ‘‘Pirin” basin (Bulgaria) was selected as a high sulphur containing sample. Different types of microorganisms were chosen and maximal desulphurization of 26% was registered. Biodesulphurization treatments were performed with three types of fungi: ‘‘Trametes Versicolor” – ATCC No. 200801, ‘‘Phanerochaeta Chrysosporium” – ME446, Pleurotus Sajor-Caju and one Mixed Culture of bacteria – ATCC No. 39327. A high degree of inorganic sulphur removal (79%) with Mixed Culture of bacteria and consecutive reduction by 13% for organic sulphur (Sorg) decrease with ‘‘Phanerochaeta Chrysosporium” and ‘‘Trametes Versicolor” were achieved. To follow the Sorg changes a set of different detection systems i.e. AP-TPR coupled ‘‘on-line” with mass spectrometry (AP-TPR/MS), on-line with potentiometry (AP-TPR/pot) and by the ‘‘off-line” AP-TPR/GC/MS analysis was used. The need of applying different atmospheres in pyrolysis experiments was proved and their effects were discussed. In order to reach more precise total sulphur balance, oxygen bomb combustion followed by ion chromatography was used

Soil water repellence increased early wheat growth and nutrient uptake

Purpose Soil water repellence causes uneven soil wetting which can constrain dryland crop and pasture establishment and yield. The same processes are likely to affect nutrient availability from soil and fertiliser, but the effects of repellence on crop growth and nutrition per se have seldom been reported. Here, we investigated early wheat (Triticum aestivum cv. Mace) growth and nutrient uptake responses to repellence. Methods Wheat was furrow-sown in severely repellent sandy loam soil (with a wettable furrow base to allow for germination) or completely wettable soil, under uniform plant density and variable topsoil thickness (20 or 100 mm) and fertiliser band placement (below or away from the seed). Tiller number, shoot dry matter, shoot N concentration, total nutrient uptake, and root length density (RLD) were determined. Results Contrary to expectations, repellence significantly increased tiller number (by up to 2 tillers per plant), shoot dry matter (by 82%), shoot N concentration (by 0.3% N), and total nutrient uptake (by 87%) at 51 days after sowing, regardless of topsoil thickness and fertiliser placement. In the furrow, RLD of repellent treatments was also nearly double that in wettable treatments when fertiliser was banded below the seed. Results suggest that preferential soil wetting of the furrow in repellent treatments favoured plant nutrient uptake under regular but low water supply. Conclusion We conclude that for water-repellent soils with limited water supply, water harvesting techniques such as furrow sowing and banding wetting agents could boost water and nutrient uptake and early crop growth

Soil water repellence increased early wheat growth and nutrient uptake

Purpose: Soil water repellence causes uneven soil wetting which can constrain dryland crop and pasture establishment and yield. The same processes are likely to affect nutrient availability from soil and fertiliser, but the effects of repellence on crop growth and nutrition per se have seldom been reported. Here, we investigated early wheat (Triticum aestivum cv. Mace) growth and nutrient uptake responses to repellence. Methods: Wheat was furrow-sown in severely repellent sandy loam soil (with a wettable furrow base to allow for germination) or completely wettable soil, under uniform plant density and variable topsoil thickness (20 or 100 mm) and fertiliser band placement (below or away from the seed). Tiller number, shoot dry matter, shoot N concentration, total nutrient uptake, and root length density (RLD) were determined. Results: Contrary to expectations, repellence significantly increased tiller number (by up to 2 tillers per plant), shoot dry matter (by 82%), shoot N concentration (by 0.3% N), and total nutrient uptake (by 87%) at 51 days after sowing, regardless of topsoil thickness and fertiliser placement. In the furrow, RLD of repellent treatments was also nearly double that in wettable treatments when fertiliser was banded below the seed. Results suggest that preferential soil wetting of the furrow in repellent treatments favoured plant nutrient uptake under regular but low water supply. Conclusion: We conclude that for water-repellent soils with limited water supply, water harvesting techniques such as furrow sowing and banding wetting agents could boost water and nutrient uptake and early crop growth

A review on ESG investing: Investors' expectations, beliefs and perceptions

This study examines the recent literature on the expectations, beliefs and perceptions of investors who incorporate Environmental, Social, Governance (ESG) considerations in investment decisions with the aim to generate superior performance or make a societal impact. Through the lens of equilibrium models of agents with heterogeneous tastes for ESG investments, green assets are expected to generate lower returns in the long run compared to their non-ESG counterparts. However, in the short run, ESG investments can outperform non-ESG investments through various channels. Empirically, results for the relative performance to ESG investment are mixed. We find strong empirical evidence in the literature that investors have a preference for ESG and that their actions can generate positive social impact through engagement. The shift towards more sustainable policies in firms is motivated by the increased market values and the lower cost of capital of green firms driven by investors’ choices

Automatic Detection of Volcanic Unrest Using Blind Source Separation with a Minimum Spanning Tree Based Stability Analysis

Repeated synthetic aperture radar (SAR) acquisitions can be utilized to produce measurements of ground deformations and associated geohazards, such as it can be used to detect signs of volcanic unrest. Existing time series algorithms like permanent scatterer analysis and small baseline subset are computationally demanding and cannot be applied in near real time to detect subtle, transient, and precursory deformations. To overcome this problem, we have adapted a minimum spanning tree based spatial independent component analysis method to automatically detect sources related to volcanic unrest from a time series of differential interferograms. For a synthetic dataset, we first utilize the algorithm's capability to isolate signals of geophysical interest from atmospheric artifacts, topography, and other noise signals, before monitoring the evolution of these signals through time in order to detect the onset of a period of volcanic unrest, in near real time. In this article, we first demonstrate our approach on synthetic datasets having different signal strengths and temporal complexities. Second, we demonstrate our approach on a couple of real datasets, one acquired in 2017-2019 over the Colima volcano, Mexico, showing the occurrence of previously unrecognized short-term deformation events and the other over Mt. Thorbjorn in Iceland acquired over 2020. This shows the strength of the deep learning application to differential interferometric SAR measurements, and highlights that deformation events occurring without eruptions, which may have previously been undetected