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In order to improve the effect of injection–production coupling development to improve crude oil recovery in complex fault-block reservoirs, we carried out a physical simulation experiment based on a sandpack model of transforming water-driven development into injection–production coupling development and quantitatively evaluated the influence of rounds of injection pressure coupling on the crude oil mobilization in reservoirs with different permeability levels and on oil recovery. Meanwhile, the characteristics of residual oil were studied via a numerical simulation method. The mechanism of increased oil production via injection–production coupling development was revealed by analyzing the water and oil contents, formation pressure, and streamline fields through the establishment of mechanism models. The results of the physical experiment show that injection–production coupling can improve the recovery effect of medium- and low-permeability reservoirs by 55.66%. With an increase in the injection pressure, the oil recovery percentage of the low-permeability sandpack model at 20 MPa is 100%, and this study finds that injection–production coupling is the main way to develop the recoverable oil in a low-permeability reservoir. The numerical simulation results show that among the four remaining oil distribution types (interwell-enriched, low-permeability zone-enriched, well network imperfection, and mismatch between injection and production), the interwell-enriched type of the remaining oil reserves accounts for the highest proportion (48.52%). The simulation results of the mechanism model show that water-driven development easily leads to streamline solidification, resulting in ineffective circulation of the injected water. Compared with conventional water-driven development, the pressure propagation range is significantly increased in injection–production coupling development. The reservoir streamline distribution is more continuous and uniform, and the flooding wave is wider in volume and range. This research provides a theoretical basis for the injection–production coupling technology policy in complex fault-block reservoirs. [ABSTRACT FROM AUTHOR]

Heilangou gold deposit is located in the east of Jiaobei area, and the proven gold reserves currently account for more than 70 % of that of Penglai area. The intrusive rocks related to mineralization in this area are rich in silicon, and alkali while lacking magnesium, with TFeO (1.22 %-12.36 %,with an average of 3.38 %),and the Rb mass fraction is less than 270×10-6. The REE chondrite-normalized distribution curve has an obvious right-leaning distribution model and weak positive Eu anomaly, and the w (Rb)/w (Nb) value is 7.8-36.0,which is A-type granite, with the characteristic of low-Mg adakites. The crystal ages of intrusive rocks measured by the LA-ICP-MS zircon U-Pb method are respectively (172.8±0.3)Ma, (172.8±0.4)Ma, and (174.0±0.4)Ma, which are all related to magmatic activity in the early Middle Jurassic. Heilangou gold area is mainly controlled by the lower crust and lithospheric mantle, and the source of ore-forming material is related to the partial melting of the crust and upwelling of lithospheric mantle and asthenosphere mantle, which belongs to the mixed material source of crust and mantle. [ABSTRACT FROM AUTHOR]

Background: The widespread use and misuse of antimicrobials are the major driving factor for antimicrobial resistance (AMR) that threatens the health of human beings globally. Thus, monitoring antimicrobial consumption at national level is crucial to prevent and contain AMR. Nevertheless, there is no well-established system for recording and reporting of antimicrobial consumption in Ethiopia. Hence, the national antimicrobial consumption survey was conducted to generate evidence for decision-making on the appropriate use of antimicrobials in Ethiopia and tackle AMR. Methods: All imported and locally manufactured antimicrobials from 2017 to 2019 were from the Ethiopian Food and Drug Authority and local manufacturers database, respectively. Data were collected and analyzed descriptively in accordance with the World Health Organization (WHO) Anatomical Therapeutic Chemical (ATC) and defined daily doses (DDD) classification and methodology. Results: The average DDD/1,000 inhabitants for all antimicrobials was 15.36. The DDD/1,000 inhabitants fell down sharply from 37.03 in 2017 to 4.30 in 2018, before slightly rising to 4.75 in 2019. The majority of the consumed antimicrobials were comprised of oral antimicrobials (98.6%), while parenteral antimicrobials made up 1.4%. Tetracyclines (35.81%), fluoroquinolones (20.19%), macrolides (13.92%), antiretrovirals (10.57%), and cephalosporins (9.63%) were the most frequently consumed classes of antimicrobials during the three years period. About 75.83% of the consumed antimicrobials fall under the WHO AWaRe classification and 67.87% of antimicrobial consumption was from the WHO Access class medications, with Watch and Reserve classes accounting for 32.13% and <1%, respectively. Similarly, about 86.90% of the antimicrobials fall under the Ethiopian AWaRe classification, with Access, Watch, and Reserve accounting for 87.73%, 12.26%, and <1%, respectively. Conclusion: Due to the peculiarities of our settings, our findings may have some similarities and differences with similar studies from other countries. Hence, we recommend for all concerned bodies to work collaboratively to improve monitoring of antimicrobial consumption at different levels of the Ethiopian healthcare tier system. Future work is necessary to establish a strong system of reporting of antimicrobial consumption patterns in Ethiopia. [ABSTRACT FROM AUTHOR]

Protection of cultivated land around cities has been an important topic in the territorial spatial planning, which is of great significance in guaranteeing ecological and food security and contributing to the sustainable development of cities. In this study, we quantified the synergistic relationship between natural quality characteristics and surrounding site conditions of cultivated land, by integrating the three-line demarcation requirements of permanent basic cultivated land red line, ecological red line, and urban development boundary. On the basis of Land Evaluation and Site Assessment (LESA) theory, this study establishes a cultivated land suitability evaluation system based on the comprehensive evaluation system of natural quality and site conditions, establishes cultivated land use and protection zones around the main urban area of Anshan City, and puts forward the control measures of cultivated land protection zones. The results showed that the cultivated land in the main urban area of Anshan could be divided into four types: permanent basic cultivated land area accounting for 80.7%, permanent basic cultivated land reserve area accounting for 10.15%, urban development boundary flexible use area accounting for 3.98%, and ecological restoration area accounting for 5.17%. The evaluation results reflected the differences in the cultivated land quality and site environment stability and integrated the policy requirements of the three-line demarcation. The layout of cultivated land around the main urban area was effectively explored, and the permanent basic farmland protection zone was delineated, which met the requirements of flexible development of urban boundaries and control of ecological red line for effective land use. [ABSTRACT FROM AUTHOR]

The western Baltic Sea cod (WBC) stock is at historically low levels, mainly attributed to high fishing pressure and low recruitment. Stable stock assessment metrics suggested recovery potential, given appropriate fisheries management measures. However, changing environmental conditions violate stability assumptions, may negatively affect WBC, and challenge the resource management. The present study explored 42 years of changes in WBC biological parameters. WBC body condition gradually decreased over the last decades for juveniles and adults, with a rapid decrease in recent years when a single cohort dominated the overfished stock. The hepato-somatic index and the muscle weight decreased by 50% and 10% in the last 10 years, respectively, suggesting severely decreasing energy reserves and productivity. The changes in energy reserves were associated with changes in environmental conditions (increase in bottom water temperature, expansion of hypoxic areas during late summer/autumn), and changes in diet composition (less herring). A key bottleneck is the warming and longer-lasting summer period when WBC, trapped between warmed shallow waters and hypoxic deeper waters, have to mobilize energy reserves to account for reduced feeding opportunities and thermal stress. Our results suggest that stock recovery is unlikely to happen by fisheries management alone if environmental trajectories remain unchanged. [ABSTRACT FROM AUTHOR]

The article highlights that many Arab countries have high spending without developing a solid revenue base or adequate emergency reserves, public debt levels have skyrocketed, and governments balance sheets have struggled to cope with waves of crises and their required responses. It also discusses that many Arab countries have faced compounded shocks in the humanitarian and health spheres, in real economic and financial trends, and in the management of their pre-existing sovereign debts.

This paper proposes a comprehensive methodology for determining the converter droop settings to ensure the voltage security in a multi-terminal direct current (MTDC) grid. The novelty lies in the introduction of the concept of over- and under-voltage containment reserves in analogy to the frequency containment reserves in AC systems. This not only gives a distinction of the contribution between the converters in rectifying and inverting modes, but also significantly facilitates the sizing of the necessary amount of reserves within their available headroom capacity of power. In particular, the constraints of converter outages, converter rating, and DC voltage deviations are all taken into account in the design of reserves. The effectiveness of the proposed approach is demonstrated by a contingency power flow analysis algorithm and EMT simulations of a four-terminal MTDC grid. [ABSTRACT FROM AUTHOR]

Global warming is increasing the vulnerability of ecosystems, especially in peninsular Spain. Biosphere Reserves are internationally protected areas that seek to protect biodiversity and, at the same time, promote sustainable development. Evaluating these protected areas is essential to verify environmental changes and establish priorities in their management. In this work, we have studied the time trends of NDVI in the high mountain Biosphere Reserves of Spain from 2001 to 2016 to check if the trend patterns are associated with some environmental variables. Significant differences were found between NDVI trends and high mountain Biosphere Reserves. Firstly, significant positive trends in NDVI were observed when analysing both reserves together. However, significant differences were found between the two reserves. The Ordesa-Viñamala Reserve shows higher positive NDVI trends and lower negative trends, while this pattern is reversed in Sierra Nevada. We observed how the fluctuations in temperature and drought due to climate change have already negatively affected the Mediterranean reserve (Sierra Nevada). In contrast, the alpine reserve (Ordesa-Viñamala) maintains positive NDVI trends. This study helps to close the gap in information related to Biosphere Reserves, which gives value to the work that is being carried out by the local communities that make up them, generating statistically significant results that Biosphere Reserves are protected areas that help us understand how to manage and govern socioecological systems sustainably. • The study assesses NDVI trend in the Spanish high mountain Biosphere Reserves. • We analysis the association between NDVI trends and environmental variables. • Significant differences in NDVI trend frequency found between the reserves. • Climate change is having effects on reserves NDVI trends. • Trend data is key to ensuring reserves take into account in political decisions. [ABSTRACT FROM AUTHOR]

Successive calamities, including bark beetle outbreaks and windthrow, have caused severe damages in German forests since 2018. The loss of forest stands as an important source of income makes it increasingly difficult for forest management to secure sustainable revenues, which in turn threatens the livelihood of many private forest enterprises. In addition, valuable ecosystem services are affected and there is a lack of financial resources for the necessary investments in reforestation and climate change adaptation. An online survey was used to investigate the attitude of private forest enterprises towards solving liquidity problems. [ABSTRACT FROM AUTHOR]

The AquaCrop simulation model, originally designed for annual crops, is expanded here to simulate alfalfa, a perennial forage crop. A new routine was added to the model to mimic the assimilate partitioning between above and below-ground plant parts to account for the utilization of reserves in Spring and for their storage in the Fall. The simulation of the transfer of assimilates requires only three extra crop parameters which makes the model also easy to calibrate. To evaluate the model, yield data collected in Louvain-La-Neuve (Belgium), Isparta (Turkey), and Ottawa (Canada) for different alfalfa cultivars, various years and field and irrigation management strategies were used. To assess the accuracy and robustness of the simple assimilate remobilization process, simulations were run for the three different environments with a common set of crop parameters which were parameterized. The dispersion between the observed and simulated cumulative dry above-ground biomass during the growing cycle was small (r² = 0.97; nRMSE = 11%; Nash-Sutcliffe model EF = 0.97), and a systematic over- or underestimation by the model was not observed (Willmott's index of agreement, d = 0.99). When evaluating the goodness of fit of the 81 individual harvest events, the results were still very satisfactory although the nRMSE doubled. The simulations indicated that the AquaCrop model adapted to perennial crops and with a novel storage-remobilization routine, could predict well alfalfa yields in various climates and environments, with and without water and fertility stress, and for three different alfalfa cultivars. • The AquaCrop simulation model is expanded to simulate perennial forage crops. • A simple routine describes the transfer of assimilates between the above ground biomass and the below-ground storage organs. • Variations in partitioning along the season was simulated by increasing or reducing the crop water productivity. • Simulations were run with a common set of crop parameters for different years, alfalfa cultivars, climates, and environments. • The simulations indicated that AquaCrop can well predict the total yield of alfalfa that can be expected in various environments. [ABSTRACT FROM AUTHOR]

In recent years, numerous research works have been reported on the flexural response of aluminium alloy tubular cross-sections. However, studies on monosymmetric cross-sections and particularly channel (C-) sections are limited, albeit their increased usage in structural applications. This paper aims to address this knowledge gap providing an improved understanding about the minor axis bending behaviour of C-sections through an experimental and numerical investigation. In total 14 specimens made from 6082-T6 heat-treated aluminium alloy were subjected to four-point bending. Tensile coupon tests were also performed to determine the mechanical properties of the examined aluminium alloy. The obtained experimental results are analysed and discussed. A series of geometrically and materially nonlinear analyses were also carried out to study the flexural performance of C-sections in two aluminium alloys and two bending orientations over a range of cross-sectional aspect ratios and slendernesses. The experimental and numerical results are utilised to assess the European design standards. The applicability of the Continuous Strength Method and the Direct Strength Method is also evaluated. An alternative design method based on the plastic effective width concept is proposed for slender C-sections subjected to minor axis bending. This method accounts for the inelastic reserve capacity which is in accordance with the experimental and numerical observations. • Flexural response of aluminium alloy C-sections is investigated. • 14 four-point minor axis bending tests are reported. • A wide parametric study is carried out. • Current codified design provisions are assessed. • The plastic effective width method is proposed for slender C-sections under minor axis bending. [ABSTRACT FROM AUTHOR]

The frequent best practice for managing large low-grade run-of-mine (ROM) stockpiles is to average the entire stockpile to only one grade. Modern ore control and mineral processing procedures need better precision. Low-precision models hinder the ability to create a digital mine-to-mill model and optimize the holistic mining process. Prior to processing, poorly characterized stockpiles are often drilled and sampled, despite there being no geological reason for relationships between samples to exist. Stockpile management is also influenced by reserve accounting and lacks a common operational workflow. This paper provides a review of base and precious metal run-of-mine (ROM) pre-crusher stockpiles in the mining industry, and demonstrates how to build a spatial model of a large long-term stockpile using fleet management system (FMS) data and geostatistical code in Python and R Studio. We demonstrate a framework for modelling a stockpile believed to be readily workable for most modern mines through use of established geostatistical modelling techniques applied to the type of data generated in a FMS. In the method presented, each bench of the stockpile is modeled as its own geological domain. Size of dump loads is assumed to contain the same volume of material and grade values that match those of the grade data tracked in the FMS. Despite the limitations of these inputs, existing interpolation techniques can lead to increased understanding of the grade distribution within stockpiles. Using the framework demonstrated in this paper, engineers and stockpile managers will be able to leverage operational data into valuable insight for empowered decision making and smoother operations. [ABSTRACT FROM AUTHOR]