Conservative Systems Research Articles

Soil hydro-physical variables and crop residues determinate runoff, soil loss, and glyphosate and AMPA concentration in the aqueous phase under simulated rainfall events.

Soil structural degradation and water erosion processes were observed even in no-tillage schemes in the Pampas region. Within these conservation systems, agrochemical application per hectare is one of the highest globally. Thus, this entails a serious risk of water contamination. The objectives of this study were to (1) test the hypothesis that the hydrological dynamics and sediment concentration related to surface runoff were conditioned by soil structure regardless of the presence of maize (Zea mays L.) crop residue and (2) assess the incidence of maize crop residue on glyphosate and aminomethylphosphonic acid (AMPA) concentration in runoff. The soil under study corresponded to Arroyo Dulce Series (Typic Argiudoll silty loam soil). Rain simulations were performed in the laboratory on undisturbed soil samples. Total runoff and infiltration rate were similar between treatments with C(+) and without C(-) maize crop residues (C(+) 1381.40mL and 14.27mm h-1, C(-): 1529.70mL and 21.67mm h-1). The C(-) treatments showed a higher sediment concentration than C(+) (1.58 and 0.42g 100mL-1, respectively). Glyphosate and AMPA average values in runoff were 15.9 and 33.9µg L-1. High variability of the hydro-physical properties and occurrence of soil structure, particularly platy ones, were detected. The hydrological variables were conditioned mainly by the occurrence of platy structures regardless of crop residue presence. Glyphosate concentration was increased in the first runoff event by the presence of corn residues, while AMPA concentrations were higher in the second runoff event in both residue treatments. In this study, maize residue on the soil surface protected the soil from sediment detachment but did not change runoff or infiltration. Thus, the implementation of agricultural management practices that promote vegetative residue cover has shown positive results to erosion.

Extreme events and extreme multistability in a nearly conservative system.

This study investigates the emergence of extreme events in a complex variable dynamical system. In the absence of an external forcing, the model exhibits nearly Hamiltonian dynamics. When we set the system to a nearly conservative state and perturb it with external forcing, the formation of the onset of the extreme events was detected. By applying nullcline analysis and the system's vector field, we explored the underlying mechanism that leads to extreme events. Furthermore, we have conducted a thorough investigation to show the dynamic origins of extreme amplitude events and their transitions. The hardware electronic experiment is used to validate the numerical results of the onset of extreme events, and the results obtained are in good agreement with one another.

Soil biological fertility evolution in a chronosequence under long‐term rice cultivation after land reclamation in China

AbstractLand use significantly affects soil biological fertility through impacts on carbon (C) and nitrogen (N) cycling. The present study investigated the effects of long‐term rice cultivation after tidal flat reclamation on soil C and N metabolism, microbial biomass and biological fertility. Eighteen composite topsoil (0–20 cm) samples were identified in a chronosequence of coastal reclamation areas (0–700 years old) in subtropical monsoon climate zone, namely tidal flat (T0), salt marsh soil (S10) and paddy soil (P50, P100, P300 and P700). Using ANOVA analysis, mono‐exponential regression model, and multiple linear regressions, soil organic matter (SOM), total nitrogen (TN), cumulative C mineralization content (Ct) and N mineralization content (Nt), basal soil respiration (BSR) and microbial biomass C and N (MBC and MBN) in the P50‐P700 samples were significantly higher than those in the T0 and S10 samples, whereas C metabolic quotients (qCO2) in the P50‐P700 were significantly lower than those in the T0 and S10 samples. The time to steady state for SOM and TN are 357 years and 80 years, respectively; 133 and 221 years for Ct and Nt, respectively; and 318 and 183 years for MBC and MBN, respectively. Also, a soil biological fertility index (SBFI) was calculated on the basis of SOM, BSR, Ct, MBC, qCO2 and qCM. P100‐P300 samples had the highest SBFI score (28.7) and ranked in the class V (very high) of biological fertility, achieving steady‐state conditions after 146 years. SBFI was significantly positively correlated with SOM, TN, MBC, MBN, BSR, Ct and Nt, whereas it was significantly negatively correlated with pH, qCO2 and C mineralization quotient (qCM). MBC and qCM were two independent variables with considerable positive effects on SBFI. Long‐term rice cultivation could facilitate C and N accumulation and enhance biological fertility in soils via microbial activity, especially within 300 years. Our findings demonstrate that rice cultivation has the potential to enhance soil C and N accumulation. Carbon‐related SBFI is suitable for assessing soils under long‐term rice cultivation, mainly because the rice paddy field is an intensive and conservative system.

Real-Time Precision Irrigation System for Optimal Crop Yield and Water Conservation

Real-Time Precision Irrigation System for Optimal Crop Yield and Water Conservation

Electronic circuit and image encryption for a new 3D nonuniformly conservative system

Electronic circuit and image encryption for a new 3D nonuniformly conservative system

Construction method and circuit design of a high-dimensional conservative chaotic system with binary linear combinations

Construction method and circuit design of a high-dimensional conservative chaotic system with binary linear combinations

Assessment of water conservation and water intensification level based on AHP-fuzzy comprehensive evaluation model

Scientific evaluation of water conservation and water intensification level is an important prerequisite for addressing water resource shortage. In the current research, there are problems of confusing evaluation indicator systems and unscientific evaluation results. The paper first constructed the evaluation indicator systems of water conservation and water intensification based on the different connotations of the two, and then evaluated the utilization level of the two respectively by using AHP-fuzzy comprehensive evaluation model. The results indicated that from 2010 to 2022, the level of water conservation and water intensification in Zhengzhou both showed an upward trend, but the conservation level was higher than that of intensification. Therefore, promoting water intensification is the key to realize scientific water use in Zhengzhou in the future. Improving conservation level should prioritize the improvement of agricultural and domestic water use, while enhancing intensification level should prioritize the improvement of comprehensive and ecological water use. Separate evaluation of the two is more conducive to identifying weaknesses in their respective processes. Thus, more targeted and scientific improvement measures can be taken to enhance the level of urban water resource development and utilization.

A complex relationship between cropping systems and soil macrofauna: Influence of practice intensity, taxa and traits

Larger soil organisms have often been reported as the most sensitive to disturbances caused by cropping practices. However, soil macrofauna comprises groups with a wide diversity of morphological and ecological features, which may respond differently to applied practices. In order to further assess the effect of cropping systems on soil macrofauna, macrofauna organisms were extracted from soil blocks over 21 fields (each comprising three plots) located in the Paris basin, in autumns 2020 and 2021. Fields belonged to conventional, conservation or organic systems, either long-established (≥ 7 years) or in transition (≤ 3 years). Tillage, pesticide treatment and organic matter input intensity were assessed in each field using composite indexes of practice intensity. Macrofauna density and diversity, earthworm ecological categories, species richness and functional traits were investigated. Our results showed that the density and diversity of macrofauna demonstrated few differences regarding different cropping systems, with highly variable effects across groups and years. Specific macroarthropod groups responded differently to tillage, pesticide treatment and organic input intensity, but not over the two years of the study. Regarding earthworms, high tillage intensity had a negative effect on the density and biomass of epi-anecic juveniles and on species with a small body size. Higher organic matter inputs had a negative effect on the density and biomass of endogeic earthworms, and could be related to several earthworm functional traits (body length, mass/length ratio, carbon preferences). Effects of pesticide treatments were less clear, although they could have impacted some earthworm species. More generally, taxonomic and functional trait approaches of earthworm community led to similar conclusions. Overall, our results support the need to account for (i) the actual intensity of practices in cropping systems and (ii) the different taxonomic, trophic and ecological groups of macrofauna, in order to assess the effects of cropping systems on soil biodiversity.

Design and Fabrication of Energy Conservation System using Fly Wheel

The aim of this project is to design and manufacture an energy conservative system using flywheel and to analyze the input and output characteristics of the designed system. Using the principle of conservation of energy the system, it recovers energy from the input, producing enough energy to reach the installed project and producing additional energy to power the external electricity to be used. Design and analyze energy conservative systems using flywheel for this project, the continuity of kinetic energy is proportional to its mass density of flywheel. This huge kinetic energy is converted into electrical energy according to Lee Tseung's theory that controls the production of electrical energy. The system can be used as a backup power source to equipment used to provide electricity in case of a power outage, providing uninterrupted power supply. It can be used as an energy storage device for renewable energy sources. However, the proposed project cannot operate for a long time due to the high energy consumption in the fault zone. Finally, significant losses occur in the entire system, such as air friction losses and mechanical losses, which reduce efficiency.

Cross-channel image encryption algorithm on the basis of a conservative hyperchaotic system

In image encryption, the traditional encryption means of scrambling and diffusion are widely used, but they fail to completely eliminate the correlation between the channels of the ciphertext image and still exist security risks. The selecting channel and position scrambling and cross-channel S-shaped diffusion methods proposed in this study push the encryption to a new depth. Compared with ordinary methods, it is more thorough in disrupting pixel positions, increases the complexity of pixel relationships between different channels, and substantially improves the unpredictability of encryption. To support this approach, we design a four-dimensional conservative hyperchaotic system with a very large hyperchaotic interval, which combines the high randomness of the conservative system and the broad key-space property of the hyperchaotic system, effectively defending against the risk of phase-space reconstruction aroused by missing attractors and reducing the possibility of being cracked. We deeply analyze the dynamic properties of the system by means of phase diagrams, bifurcation diagrams and Lyapunov exponents. The cross-channel scrambling and diffusion encryption algorithm designed based on this system not only ensures the security of image information during transmission, but also greatly enhances the ability to resist various attacks. The proposal of this method undoubtedly brings a secure solution to the field of image encryption.

Dissociation and Loss: a Challenge for Sustainable and Inclusive Conservation

ABSTRACT The agents of deterioration (AoD) offer a structured categorization of hazards to collections: they are a basis for risk-informed preservation management. In drawing up the AoD their creators were not ignorant of wider societal issues of concern to conservators, but they envisaged them to be part of a broader institutional activity located beyond the scope of preventive conservation. Within conservation, there have been discussions about additional agents: social, cultural, or political causes of loss. Their continued exclusion from the AoD may mistakenly be interpreted as a lack of consideration of such concerns. There are reasons to limit the scope of an institution’s preventive conservation system but not everyone agrees that those reasons are sufficient to justify this limitation. This paper is a discussion and disagreement by two authors. Henderson argues that dissociation should capture any loss of meaning resulting from any aspect of conservation practice, including cleaning, documentation, failure to respect beliefs, etc. She argues that dissociation from context may stop preventive conservators from identifying and respecting optimal traditional sustainable methods and techniques. Waller argues that the threat of losing context information about collection items should be managed as part of the wider cultural heritage institution’s role and resolved through its engagement with the community. He acknowledges that preventive conservation can contribute to understanding and mitigating this form of loss, but advocates that primary responsibility must be situated at a higher level than the preventive conservation remit.

Plant Genetic Resources for Food and Agriculture: The Role and Contribution of CREA (Italy) within the National Program RGV-FAO

Conservation, characterization and exploitation of agrobiodiversity are key factors to guarantee food security and face future challenges such as climate changes. These issues are the subject of a series of international agreements, such as the Convention of Biological Diversity, with its Nagoya Protocol, and the International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA) adopted in 2001 and entered into force in 2004. Italy ratified the Treaty in 2004 and instituted a long-lasting program, RGV-FAO, to implement it. CREA is one of the three organizations involved in the RGV-FAO Program, together with the National Research Council (CNR) and Reti Semi Rurali. CREA maintains a total of 40,186 accessions including cereals, vegetables, fruits, forages, industrial crops, forest and woody crops, medicinal and aromatic plants, and their wild relatives. Accessions are conserved using different ex situ conservation systems (seeds, in vivo plants, vegetative organs and in vitro plantlets), and characterized using genetic, morpho-phenological and/or biochemical methods. Herein, we will present the CREA long-lasting program RGV-FAO with some examples of the use of plant genetic resources in breeding programs, including molecular approaches. Some critical issues related to access and benefit sharing in PGRFA, such as the Nagoya Protocol and the Digital Sequence Information, will be discussed, highlighting their potential impact on food security and on the advancement of knowledge.

Photon superfluidity through dissipation

Superfluidity—frictionless flow—has been observed in various physical systems such as liquid helium, cold atoms, and exciton polaritons. Superfluidity is usually realized by cooling and suppressing all dissipation. Here we challenge this paradigm by demonstrating signatures of superfluidity, enabled by dissipation, in the flow of light within a room-temperature oil-filled cavity. Dissipation in the oil mediates effective photon-photon interactions which are noninstantaneous and nonlocal. Such interactions were expected to severely limit the emergence of superfluidity in conservative photonic systems. Surprisingly, when launching a photon fluid with sufficiently high density and low velocity against an obstacle in our driven-dissipative cavity, we observe a record suppression of backscattering. Our experiments also reveal the reorganization dynamics of photons into a nonscattering steady state and a qualitatively changing behavior of the optical phase as light propagates around the obstacle. The phase is locked between the laser and the obstacle but evolves with the intensity in the wake of the obstacle where the density of the photon fluid and its mean-field interaction energy decrease. Using a generalized Gross–Pitaevskii equation for photons coupled to a thermal field, we model our experiments and elucidate how the noninstantaneous and nonlocal character of interactions influences the suppression of scattering associated with superfluidity. Beyond providing the first signatures of cavity photon superfluidity, and of any superfluid both at room temperature and in steady state, our results pave the way for probing photon hydrodynamics in arbitrary potential landscapes using structured mirrors. Published by the American Physical Society 2024

Evaluation of upper-room ultraviolet germicidal irradiation system for air disinfection and energy conservation in multi-patient ward

High occupancy rates significantly increase the risk of airborne transmission of respiratory infectious diseases in multi-patient wards. While increasing air supply can effectively reduce airborne transmission, it also substantially raises energy consumption. Therefore, developing low-energy methods in multi-patient wards to suppress airborne transmission is essential. This study aims to evaluate the inactivation performance of upper-room ultraviolet germicidal irradiation (UVGI) against SARS-CoV-2 virus aerosols in a typical multi-patient ward using computational fluid dynamics at different ventilation rates, as well as its energy-saving effects. Upper-room UVGI reduced the virus aerosol concentrations, with a maximum decrease of up to 159 copies/m3 in the occupied zone (zone less than 2.1 m in height) observed at 8 ACH. However, increased ventilation rates limited the inactivation performance of upper-room UVGI. Two parameters of UVGI, irradiation height and irradiation flux, had been detailly evaluated. Elevating the irradiation height of upper-room UVGI could significantly enhance the inactivation performance. Increasing irradiation height from 0.3 to 0.6 m reduced the concentrations in the occupied zone by up to 11 copies/m3, while a further increase to 0.9 m decreased the concentrations by up to 55 copies/m3. However, increasing irradiation flux could only approximately linearly enhance the virus aerosol inactivation performance of upper-room UVGI. The energy consumption evaluation of upper-room UVGI shows that UVGI activation could conserve 100 kWh per year in one multi-patient ward, with a maximum saving of 333.7 kWh. These findings provide insights into the setups strategies and the energy-saving performance of upper-room UVGI systems in multi-patient wards.

A novel five-dimensional non-Hamiltonian conservative hyperchaotic system with multiple amplitude-modulated behaviors

In this work, we propose a new five-dimensional non-Hamiltonian conservative hyperchaotic system with infinitely many equilibrium points. Both this system and its fractional-order system are characterized by multiparametric modulation of the system amplitude. Variation of the parameter a can cause the system’s motion state to transform between quasi-periodic, chaotic, and hyperchaotic. This system shows its multistability when the initial value x10 is changed. It is important to note that the order q3 in fractional-order system not only controls the system amplitude but also affects the system property. NIST (National Institute of Standards and Technology) tests illustrate that the conservative system can be applied as a random number generator. Finally, a DSP (Digital Signal Processing) based hardware experiment platform confirms the physical realizability of the system.

Conservation tillage: a way to improve yield and soil properties and decrease global warming potential in spring wheat agroecosystems.

Climate change is one of the main challenges, and it poses a tough challenge to the agriculture industry globally. Additionally, greenhouse gas (GHG) emissions are the main contributor to climate change; however, croplands are a prominent source of GHG emissions. Yet this complex challenge can be mitigated through climate-smart agricultural practices. Conservation tillage is commonly known to preserve soil and mitigate environmental change by reducing GHG emissions. Nonetheless, there is still a paucity of information on the influences of conservation tillage on wheat yield, soil properties, and GHG flux, particularly in the semi-arid Dingxi belt. Hence, in order to fill this gap, different tillage systems, namely conventional tillage (CT) control, straw incorporation with conventional tillage (CTS), no-tillage (NT), and stubble return with no-tillage (NTS), were laid at Dingxi, Gansu province of China, under a randomized complete block design with three replications to examine their impacts on yield, soil properties, and GHG fluxes. Results depicted that different conservative tillage systems (CTS, NTS, and NT) significantly (p < 0.05) increased the plant height, number of spikes per plant, seed number per meter square, root yield, aboveground biomass yield, thousand-grain weight, grain yield, and dry matter yield compared with CT. Moreover, these conservation tillage systems notably improved the soil properties (soil gravimetric water content, water-filled pore space, water storage, porosity, aggregates, saturated hydraulic conductivity, organic carbon, light fraction organic carbon, carbon storage, microbial biomass carbon, total nitrogen, available nitrogen storage, microbial biomass nitrogen, total phosphorous, available phosphorous, total potassium, available potassium, microbial counts, urease, alkaline phosphatase, invertase, cellulase, and catalase) while decreasing the soil temperature and bulk density over CT. However, CTS, NTS, and NT had non-significant effects on ECe, pH, and stoichiometric properties (C:N ratio, C:P ratio, and N:P ratio). Additionally, conservation-based tillage regimes NTS, NT, and CTS significantly (p < 0.05) reduced the emission and net global warming potential of greenhouse gases (carbon dioxide, methane, and nitrous oxide) by 23.44, 19.57, and 16.54%, respectively, and decreased the greenhouse gas intensity by 23.20, 29.96, and 18.72%, respectively, over CT. We conclude that NTS is the best approach to increasing yield, soil and water conservation, resilience, and mitigation of agroecosystem capacity.

Research on shape-controllable generalized multi-cluster Hamiltonian conservative chaotic flow systems and their FPGA implementation

Research on shape-controllable generalized multi-cluster Hamiltonian conservative chaotic flow systems and their FPGA implementation

Long-term outcomes of the mayo conservative hip system in patients aged 30years or less with osteonecrosis of the femoral head: mean follow-up of more than 10years.

Historically, total hip arthroplasty (THA) in very young patients has been associated with lower survivorship. However, the long-term outcomes of THA using short stems for osteonecrosis of the femoral head (ONFH) in very young patients remain unclear. Therefore, this study aimed to investigate the long-term outcomes of the Mayo conservative hip system, a short metaphyseal stabilised stem, in patients with ONFH aged ≦30years. We retrospectively reviewed 104 joints in 76 patients with ONFH who underwent THA using the Mayo conservative hip system with a minimum follow-up of 8years. The mean follow-up period was 12.5 (range, 8-19) years. Patients were categorised into two age groups (≦30years, n = 21 and > 30years, n = 83). Radiographic evaluation was used to assess stem sinking, stress shielding, and spot welds. The clinical evaluations were performed using the Japanese Orthopedic Association (JOA) hip score. Postoperative major complication and revision surgery rates were also assessed. The patient characteristics were similar between the two groups, except for the age. Revision surgeries were performed in five cases, with similar implant survival rates between the groups. Dislocations occurred in the older age group alone (four joints). One case of intra-operative periprosthetic femoral fracture was found in the younger age group. Stem sinking of > 3mm occurred in one and seven joints in the younger and older age groups, respectively. Spot welds were observed in most joints (93.2%) in modified Gruen zones 2 and 6 without significant differences between the groups. Stress shielding showed no significant differences in the frequency of occurrence or location between the two groups. Furthermore,the JOA score showed no significant difference between the two groups. The use of short stems in patients aged ≤ 30years with ONFH showed favourable long-term outcomes.

A New 4-D Conservative System with Hyperchaos and Two Saddle-Focus Hyperbolic Equilibria Points

A New 4-D Conservative System with Hyperchaos and Two Saddle-Focus Hyperbolic Equilibria Points

A visually meaningful secure image encryption algorithm based on conservative hyperchaotic system and optimized compressed sensing

A visually meaningful secure image encryption algorithm based on conservative hyperchaotic system and optimized compressed sensing