System Level Research Articles

S3Net: Semi-self-supervised neural network for visibility enhancement of speckled images

The tremendous growth of imaging sensors, which visually acquire the objects of interest, has attracted substantial interest in different engineering applications, such as underwater sonar imaging, synthetic aperture radar (SAR) imaging, and medical ultrasound imaging, etc. However, due to limited imaging environments, the intelligent vision-empowered visual information often suffers from the low usability of imaging data, e.g., Gamma-distributed speckle noise of unknown level in several imaging systems. It is commonly intractable to implement blind despeckling of visual data since the speckle noise is signal-dependent and multiplicative in nature. To improve the imaging quality, we tended to propose a semi-self-supervised neural network (termed S3Net) that enables intelligent blind despeckling in different practical applications. To be specific, our S3Net is mainly composed of two sub-networks, i.e., self-supervised feature extraction network (FExNet) and supervised feature enhancement network (FEnNet). The robustness and generalization abilities of S3Net can be accordingly guaranteed in different imaging scenarios. It is thus capable of extracting meaningful features and enhancing geometrical features under different receptive fields, leading to image quality improvement. The S3Net denoiser can balance the trade-off between noise suppression and detail preservation. Numerous experiments have been implemented on synthetic and realistic speckle-degraded imaging scenarios. Results have demonstrated that S3Net remarkably outperformed other state-of-the-art methods in terms of both qualitative and quantitative evaluations, with significant boosting on metric and visual performance.

Role of Probiotic Microorganisms in the Brain Plasticity Development

Probiotics are defined as beneficial microorganisms that are responsible for the maintenance of homeostasis mechanisms within the host system, especially in humans. Other than homeostasis, it is also used to improve a host system's cognition, immune functions, and antioxidant levels. Over the past decades, probiotic microorganisms have been used most commonly as traditional fermented foods in our country and some parts of southeast asia. These fermented food products majorly consist of Lactobacillus species, including Lactobacillus acidophilus, L. fermentum, and L. plantarum. The present study explored the potential role of three different lactobacillus strains (L. acidophilus, L. fermentum, and L. Plantarum) in forming brain plasticity changes (BPC) with the help of a cue-based learning paradigm (CBLP). Two staged behavioral studies were conducted for all behavioral analysis groups (BAG) before (without probiotic infusions - WiPI) and after probiotic infusions (with probiotic infusions - WPI) in RBLP. Behavioral responses of the WiPI & WPI phases showed the effect of a stress-free habituated environment in developing BPC and strengthening of BPC by oral infusions of probiotic microorganisms (PM). WiPI and WPI behavioral analysis were used in this study to validate BPC in a laboratory-controlled environment. Infusion of probiotic microorganisms through oral passage may have a more significant impact on the synthesis, production, and transmission of neurotransmitter precursor compounds (NPC) from the gut to the central nervous system (CNS) through the blood-brain barrier (BBB). Increased transmission of the NPC strengthens the formed plasticity changes, which results in the formation of cognitive memory functions. Thus, the present study proved that probiotic microorganisms may play a major role in cognition development through the BPC.

A quantitative analysis of the security of PoW-based blockchains

AbstractThis study analyzes the security implications of Proof-of-Work blockchains with respect to the stale block rate and the lack of a block verification process. The stale block rate is a crucial security metric that quantifies the proportion of rejected blocks in the blockchain network. The absence of a block verification process represents another critical security concern, as it permits the potential for invalid transactions within the network. In this article, we propose and implement a quantitative and analytical model to capture the primary operations of Proof-of-Work blockchains utilizing the Performance Evaluation Process Algebra. The proposed model can assist blockchain designers, architects, and analysts in achieving the ideal security level for blockchain systems by determining the proper network and consensus settings. We conduct extensive experiments to determine the sensitivity of security to four aspects: the number of active miners and their mining hash rates, the duration between blocks, the latency in block propagation, and the time required for block verification, all of which have been shown to influence the outcomes. We contribute to the findings of the existing research by conducting the first analysis of how the number of miners affects the frequency of stale block results, as well as how the delay in block propagation influences the incentives received by rational miners who choose to avoid the block verification process.

Optimal placement of light sensor for improving energy efficiency and visual comfort in smart buildings

The energy consumed by artificial lighting accounts for a significant part of the energy consumption in buildings. Thus, energy consumption can be significantly decreased using optimization techniques, such as the optimum placement of the lighting sensors. In this paper, an optimal placement method of the light sensors is presented to minimize the lighting system's equipment costs and energy consumption and also meet visual comfort under the requirements of the European standard EN12464–1 regarding illuminance-based criteria. In the beginning, based on the illumination measurement grid's mathematical model, the potential location of the sensors is determined. As an average of the dimming levels of the LED lights, the objective function has been introduced. Then, the illuminance and uniformity levels are defined as constraints for the optimization problem. The Battle Royale Optimization (BRO) algorithm is used to solve the optimization problem. Ultimately, based on the results of the BRO algorithm and the calculation of the illuminance deviation, the optimal location of the light sensors is determined. The proposed method is tested in an office room. A fuzzy logic controller is developed to regulate the lighting control system's dimming levels to evaluate the proposed method's performance with other approaches. The comparison results have shown that the proposed method is superior as regards the number of sensors and the optimal sensor position, significant savings in energy consumption of up to 30.8%, and satisfactory visual comfort per the requirements of the European standard EN12464–1.

Electrolytes for Sodium Ion Batteries: The Current Transition from Liquid to Solid and Hybrid systems.

Sodium-ion batteries (NIBs) have recently garnered significant interest in being employed alongside conventional lithium-ion batteries, particularly in applications where cost and sustainability are particularly relevant. The rapid progress in NIBs will undoubtedly expedite the commercialization process. In this regard, tailoring and designing electrolyte formulation is a top priority, as they profoundly influence the overall electrochemical performance and thermal, mechanical, and dimensional stability. Moreover, electrolytes play a critical role in determining the system's safety level and overall lifespan. This review delves into recent electrolyte advancements from liquid (organic and ionic liquid) to solid and quasi-solid electrolyte (dry, hybrid, and single ion conducting electrolyte) for NIBs, encompassing comprehensive strategies for electrolyte design across various materials, systems, and their functional applications. The objective is to offer strategic direction for the systematic production of safe electrolytes and to investigate the potential applications of these designs in real-world scenarios while thoroughly assessing the current obstacles and forthcoming prospects within this rapidly evolving field.

Evaluación de cepas Antárticas de Bacillus sp. como bacterias promotoras del crecimiento vegetal

In agriculture, efficient microorganisms are used, among them plant growth-promoting bacteria. This work aimed to determine, in vitro, the mechanism of action in strains of Bacillus sp. isolated from Antarctica. The analyzed characteristics of the bacterium were: catalase and hemolysis tests, Gram stain, phosphate solubilization, growth without a nitrogen source, siderophore production, and survival at different values of pH, NaCl, and temperature, which confirmed the ecological plasticity and adaptation of these strains in environments other than their origin. According to the desirable characteristics, the T5, GB-70, and B-6 strains were chosen and added to two substrates: clay and clay-compost mixture, which were sterilized and placed in 200 mL glass bottles, and a corn seed was planted in each of them. After two weeks, the following parameters were evaluated: length of root (LR), seedling height (AP), and shoot diameter (DT). The simple effect of the strains as independent variables and their interaction did not significantly affect the response variables evaluated, recording the following averages: 12.84 cm (LR), 15.28 cm (AP), and 2.26 cm (DT). Considering the substrate, the compost + clay significantly (p<0.05) influenced the LR and DT characteristics of the seedlings, with averages of 14.44 and 2.38 cm, respectively. The observed mechanisms of action distinguish promising strains that could be validated at the field level in agricultural production systems when inoculated in organic fertilizers. Keywords: antarctic microorganisms, beneficial bacteria, plant growth.

Low-carbon economic dispatch strategy for microgrids considering stepwise carbon trading and generalized energy storage

Integrating carbon trading mechanisms with generalized energy storage (GES) fully embodies the principles of green and coordinated development, serving as a crucial means to achieve low-carbon construction of microgrids. This research presents a strategy for optimizing energy allocation within microgrids to minimize carbon emissions and enhance microgrid systems' economic-environmental benefits. The strategy takes into account the use of tiered carbon trading and GES. Based on a typical microgrid system architecture, an economic dispatch model for microgrids is developed, which integrates renewable energy sources such as wind and solar storage, gas turbines, energy storage systems, and flexible resources on the demand side. The model aims to minimize carbon emissions while optimizing the allocation of resources. Subsequently, the model facilitates microgrid carbon emission control by considering the transferable, convertible, and reducible properties of GES. Furthermore, implementing a tiered carbon trading mechanism decreases carbon emissions. Finally, using a real microgrid example from a specific region in China, the results indicate that the proposed method significantly enhances the system's low-carbon level. Notably, compared to scenarios that do not consider GES, the proposed method substantially reduces total costs by 6.62% and decreases carbon emissions by 22.2%. The findings indicate that the suggested dispatch model can substantially decrease carbon emissions while simultaneously improving the economic efficiency of the microgrid system.

Design and Implementation of an Intelligent Ultrasonic System based on 51 Microcontroller

With the rapid development of microelectronics and intelligent technology, microcontroller units (MCUs) are increasingly applied in various fields. This paper proposes the design and implementation of an intelligent ultrasonic system based on a 51 microcontroller, integrating ultrasonic sensors, an LCD display, and a 51 MCU to achieve real-time distance measurement, data display, and intelligent control functions. The system utilizes a CD4069 ultrasonic sensor to transmit and receive ultrasonic waves, measuring the distance between the sensor and an object by calculating the time difference between transmission and reception. The measured distance data is processed and displayed on an LCD screen in real-time. Furthermore, the system features intelligent control capabilities, automatically adjusting and controlling devices based on the measured data, thereby enhancing the system's level of intelligence. The intelligent ultrasonic system based on the 51 microcontroller offers advantages such as low cost, high precision, and strong versatility. It can be widely used in various fields, including intelligent robots, obstacle avoidance systems, and automatic parking systems. The design and implementation of this system not only demonstrate innovative applications of ultrasonic ranging technology but also provide valuable references for the extensive application of microcontroller units in intelligent technology fields.

Comparative Analysis of Drought Effects on the Soil Moisture Level and Penetration Resistance in Conventional and Non-Conventional Tillage Systems in Maize Production

The period of extreme weather anomalies in recent years has challenged farmers, and this has encouraged greater adaptability in farming practices. In the last decade, conventional tillage systems have been complemented by more biologically based cropping systems. The research evaluated the impact of drought on soil physical parameters in maize production by testing different conventional and non-conventional tillage systems to ensure optimal soil physical parameters. In the analysis of the prevailing weather conditions, rainfall values were divided into two parts, the pre-growing season and the growing season. We studied different climatic seasons. In 2021, the soil moisture content in the upper shallow 15 cm soil layer during the sowing period in April in the case of conventional tillage was significantly lower than in reduced tillage, conservation tillage and strip tillage. The most significant difference was measured between conventional and conservation tillage, with a difference of 11.25 v/v%. The 2022 crop year was extremely dry. In June, the highest moisture value in the soil was measured in the case of strip tillage with a value of 21.64 v/v%, which was more than 60% higher than in the case of conventional and conservation tillage. In conventional tillage, a very pronounced compacted layer was observed in the lower part of the ploughed layer. This zone reached a compaction of 6.9 MPa between 28 and 34 cm, which is agronomically harmful. No compacted soil layer was found in the experiment site under conservation tillage. In the severe drought year of 2022, only the strip-till system provided the proper water management conditions for the maize stand.

Functional connectome through the human life span.

The lifespan growth of the functional connectome remains unknown. Here, we assemble task-free functional and structural magnetic resonance imaging data from 33,250 individuals aged 32 postmenstrual weeks to 80 years from 132 global sites. We report critical inflection points in the nonlinear growth curves of the global mean and variance of the connectome, peaking in the late fourth and late third decades of life, respectively. After constructing a fine-grained, lifespan-wide suite of system-level brain atlases, we show distinct maturation timelines for functional segregation within different systems. Lifespan growth of regional connectivity is organized along a primary-to-association cortical axis. These connectome-based normative models reveal substantial individual heterogeneities in functional brain networks in patients with autism spectrum disorder, major depressive disorder, and Alzheimer's disease. These findings elucidate the lifespan evolution of the functional connectome and can serve as a normative reference for quantifying individual variation in development, aging, and neuropsychiatric disorders.

Precise Fermi level engineering in a topological Weyl semimetal via fast ion implantation

The precise controllability of the Fermi level is a critical aspect of quantum materials. For topological Weyl semimetals, there is a pressing need to fine-tune the Fermi level to the Weyl nodes and unlock exotic electronic and optoelectronic effects associated with the divergent Berry curvature. However, in contrast to two-dimensional materials, where the Fermi level can be controlled through various techniques, the situation for bulk crystals beyond laborious chemical doping poses significant challenges. Here, we report the milli-electron-volt (meV) level ultra-fine-tuning of the Fermi level of bulk topological Weyl semimetal tantalum phosphide using accelerator-based high-energy hydrogen implantation and theory-driven planning. By calculating the desired carrier density and controlling the accelerator profiles, the Fermi level can be experimentally fine-tuned from 5 meV below, to 3.8 meV below, to 3.2 meV above the Weyl nodes. High-resolution transmission electron microscopy reveals the crystalline structure is largely maintained under irradiation, while electrical transport indicates that Weyl nodes are preserved and carrier mobility is also largely retained. Our work demonstrates the viability of this generic approach to tune the Fermi level in semimetal systems and could serve to achieve property fine-tuning for other bulk quantum materials with ultrahigh precision.

Feature Selection Techniques in Intrusion Detection: A Comprehensive Review

This investigation aims to explore previous research on the implementation of feature selection in intrusion detection. Feature selection has demonstrated its ability to enhance or sustain comparable classification accuracy levels for intrusion detection systems, while simultaneously improving classification efficiency. The evaluation includes an assessment of filter-based, wrapper-based, and hybrid feature selection techniques. Given that Big Data challenges can affect intrusion detection, feature selection’s classification efficiency can aid in lowering computing requirements. Older KDD intrusion detection datasets have received considerable attention in previous feature selection research. Consequently, researchers need more high-quality datasets that are available to the general public.

Dynamics of the nonlinear optical second- and third-harmonic generation in quantum well due to hydrostatic pressure and temperature

We studied the effects of hydrostatic pressure and temperature on the second- and third-harmonic generation (SHG and THG) in semi-parabolic GaAs/Al0.3Ga0.7As quantum wells. By solving the Schrödinger equation numerically, we can determine the system's sub-band energy levels and wave functions, and then calculate its optical gain. The numerical simulation results show that both temperature and hydrostatic pressure can effectively improve the nonlinear optical performance of the system. Notably, we explore the mechanisms underlying these interactions. These findings suggest a viable approach to adjust the nonlinear optical performance of GaAs/Al0.3Ga0.7As quantum system through the subtle interaction between hydrostatic pressure, temperature and structural parameters.

Measuring patient safety: the Agency for Healthcare Research and Qualityís patient safety indicators

There is a lot of interest in patient safety, but there is still little useable national level information on the actual magnitude of patient safety problems that can be used by providers and policy makers to judge performance. The AHRQ Patient Safety Indicators (PSIs) are a set of measures that can be used with hospital inpatient administrative (discharge) data to provide a perspective on patient safety. They screen for problems that patients experience as a result of exposure to the healthcare system and that are likely amenable to prevention by changes at the system or provider level. There is a growing interest in the possible use of the AHRQ PSIs in international settings. The Organization for Economic Cooperation and Development (OECD) maintains an ongoing project on Health Care Quality Indicators (HCQI) and whose goal is to develop a set of quality indicators that can be used to reliably assess quality of care across countries and raise questions about differences in quality of care internationally. Work is ongoing though a partnership between AHRQ and the Italian National Observatory on Health in the Italian Regions to test the AHRQ QIs with the Italian national hospital discharge data set. Preliminary results indicate that many of the operational issues associated with differences in coding schemes and data set structure are surmountable. With additional refinements on their clinical specificity, increased stability in their definitions over time to permit long-term monitoring and country interest within organizations such as the OECD to build on the existing scientific work of these indicators, their to help answer questions about patient safety worldwide will be significantly enhanced.

Triaxial Load Cell for Ergonomic Risk Assessment: A Study Case of Applied Force of Thumb

To assess the ergonomic risk level in work systems involving tasks performed with hands or fingers, it is necessary to know the exerted triaxial forces. To address this need, a prototype of a triaxial load cell based on principles of linear elasticity theory and mechanical problems of torsion, bending and axial load is presented. This work includes an analytical strain model for each instrumented point and its solution regarding the applied force to a triaxial load cell. The proposed load cell was calibrated and validated by performing different static experimental tests. As a case study, the applied force in three directions while the thumb activates a cigarette lighter was measured. Triaxial forces and resultant forces were obtained and compared with the parameter of 10 N established by the ergonomic standards as reference values for pressing down with the thumb, finding that the applied forces in eight tests were 23.73 N, 43.51 N, 12.69 N, 14.50 N 20.35 N, 21.67 N, 39.74 N and 46.02 N, exceeding the reference values and establishing a direct relationship with Quervain syndrome. In conclusion, the developed load cell is a valid and reliable alternative to measure many forces that cannot be obtained with commercial devices, allowing the level of ergonomic risk to be determined with great precision.

Moral injury in post-9/11 combat-experienced military veterans: A qualitative thematic analysis.

War zone exposure is associated with enduring negative mental health effects and poorer responses to treatment, in part because this type of trauma can entail crises of conscience or moral injury. Although a great deal of attention has been paid to posttraumatic stress disorder and fear-based physiological aspects of trauma and suffering, comparatively less attention has been given to the morally injurious dimension of trauma. Robust themes of moral injury were identified in interviews with 26 post-9/11 military veterans. Thematic analysis identified 12 themes that were subsumed under four categories reflecting changes, shifts, or ruptures in worldview, meaning making, identity, and relationships. Moral injury is a unique and challenging clinical construct with impacts on the individual as well as at every level of the social ecological system. Recommendations are offered for addressing moral injury in a military population; implications for community public health are noted. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Mixed (regular and chaotic) dynamics under the channeling of the high energy positrons in [100] direction of the silicon crystal and Podolskiy-Narimanov distribution

The character of motion (regular or chaotic) on the quantum level manifests itself in the statistics of the set of the system's energy levels. The completely regular case generates the sequence of the levels with exponential (Poisson) level spacing distribution; the completely chaotic one — with Wigner distribution. The most interesting case is the co-existence of the regular and chaotic motion domains in the phase space of the system under consideration. The assumption of independent generation of two level sequencies by one chaotic domain and by all regular domains leads to Berry-Robnik distribution. However, the presence of the chaotic motion domain in the phase space affects the levels produced by the regular domains via the so-called chaos-assisted tunneling (CAT) that leads to Podolskiy-Narimanov distribution of the level spacings. This distribution needs the mean amplitude of the tunnel transition and the relative contribution of the regular domains to the mean level density as the parameters. Using their estimations for the transverse motion of the high energy positrons channeling near [100] direction in the silicon crystal we found that Podolskiy-Narimanov distribution demonstrates the best agreement with the level spacing distribution.

Identifying and Responding to Lead in Drinking Water in a University Setting.

Lead is an established neurotoxicant, and it has known associations with adverse neurodevelopmental and reproductive outcomes. Exposure to lead at any level is unsafe, and the United States (US) has enacted various federal and state legislations to regulate lead levels in drinking water in K-12 schools and childcare facilities; however, no regulations exist for higher education settings. Upon the discovery of lead in drinking water fixtures in the University of North Carolina at Chapel Hill (UNC-CH) campus, a cross-campus water testing network and sampling plan was developed and deployed. The campaign was based on the US Environmental Protection Agency's (EPA) 3Ts (Training, Testing, and Taking Action) guidance. The seven-month campaign involved 5954 tests on 3825 drinking water fixtures across 265 buildings. A total of 502 (8.43%) tests showed lead above the limit of detection (1 part per billion, ppb), which represented 422 (11.03%) fixtures. Fewer than 1.5% of the tests were above the EPA action level for public water systems (15 ppb). In conclusion, systematic testing of all the fixtures across campus was required to identify localized contamination, and each entity in the cross-campus network undertook necessary roles to generate a successful testing campaign. UNC-CH established preventative measures to test drinking water fixtures every three years, which provide a framework for other higher education institutions in responding to lead contamination.

Occurrence of microplastics and metals in European seabass produced in different aquaculture systems: Implications for human exposure, risk, and food safety

Microplastics (MPs) are emerging contaminants of increasing concern as they may cause adverse effects and carry other contaminants, which may potentially compromise human health. Despite occurring in aquatic ecosystems worldwide, the knowledge about MP presence in different aquaculture systems and their potential impact on seafood products is still limited. This study aimed to determine the levels of MPs in water, feed, and European seabass (Dicentrarchus labrax) from three relevant aquaculture systems and estimate human exposure to MPs and metals through seabass consumption. The recirculating aquaculture system (RAS) had the highest MP occurrence in water and feed. MP levels in seabass followed the aquaculture system's levels in water and feed, with RAS-farmed fish presenting the highest MP load, both in the fish gastrointestinal tract (GIT) and muscle, followed by pond-, and cage-farmed fish. MPs' characteristics across aquaculture systems and fish samples remained consistent, with the predominant recovered particles falling within the MP size range. The particles were visually characterized and chemically identified by micro-Fourier Transform Infrared Spectroscopy (μFTIR). Most of these particles were fibres composed of man-made cellulose and PET. MP levels in GIT were significantly higher than in muscle for pond- and RAS-farmed fish, MPs' bioconcentration factors >1 indicated bioconcentration in farmed seabass. Metal concentrations in fish muscle were below permissible limits, posing low intake risks for consumers according to the available health-based guidance values and estimated dietary scenarios.

PowerScout: Security-Oriented Power Delivery Network Modeling for Side-Channel Vulnerability Analysis

The growing complexity of modern electronic systems leads to the design of more sophisticated power delivery networks (PDNs). Similar to other system-level shared hardware resources, the on-board PDN unintentionally introduces side channels across design layers and voltage domains which are not explicitly specified in the functional specification. Recent works have demonstrated that the exploitation of the side channel can compromise the system security such as information leakage and fault injection. In this work, we systematically investigate the PDN-based side channel as well as potential countermeasures. To facilitate this goal, we develop PowerScout, a security-oriented PDN simulation framework that unifies the modeling of different PDN-based side-channel attacks. PowerScout performs a fast nodal analysis of complex PDNs at the system level to quantitatively evaluate the severity of side-channel vulnerabilities. With the support of PowerScout, for the first time, we validate PDN side-channel attacks in the literature via simulation. Furthermore, we are able to quantitatively measure the security impact of PDN parameters and configurations. For example, towards information leakage, removing near-chip capacitors can increase intra-chip information leakage by a maximum of 23.23 dB at mid-frequency range and inter-chip leakage by an average of 31.68 dB at mid- and high-frequency range. Similarly, the optimal toggling frequency and duty cycle are derived to achieve fault injection attacks with higher success rate and more precise control. In addition, the vulnerabilities are evaluated when hiding-based countermeasures are implemented. Based on the evaluation, we can understand the optimal defense configuration and explore the trade-off between information leakage mitigation and power supply stability.