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Life cycle assessment and multicriteria decision making analysis of additive manufacturing processes towards optimal performance and sustainability
Abstract The pressing need for sustainable construction materials and processes has been driving research into the optimum environmental and economic efficiency of Additive Manufacturing (AM). Most models available for Life Cycle Assessment (LCA), however, do not capture the dynamism of real-time data and the existing levels of uncertainty, and decision-making frameworks are not adaptive to evolving sets of criteria. In this paper, these described limitations are addressed through the introduction of an integrated approach that couples predictive Life Cycle Assessment (LCA) with Gaussian Process Regression (GPR), dynamic decision criteria weighting via Stochastic Forest for Multi-Criteria Decision Analysis (MCDA), and multi-objective optimization using Particle Swarm Optimization (PSO). In this study, GPR-based predictive LCA is conducted using historical and real-time environmental data for modeling impact categories of CO2 and energy use. This methodology makes estimates of not only the mean impact but also allows quantification of the uncertainties through confidence intervals and dynamic LCA. Stochastic Forest algorithm will enhance the traditional MCDA by weighting decision criteria like cost, environmental impact, and durability, in a more dynamic manner aligning to real-time manufacturing performance for better decision-making. Further, PSO will optimize material and process parameters to balance the multiple objectives of material strength, energy efficiency, and cost-effectiveness. In this way, this integrative novel approach of machine learning with bioinspired optimization contributes to the sustainability of AM. Experimental results prove that predictive accuracy can be achieved up to 85–90% by GPR, which reduces material wastage by 12%. By using Stochastic Forest, an improvement in decision accuracy can be attained to the extent of 15–20%, together with a cut in costs of about 10%. For its part, PSO optimizes design and manufacturing parameters for the materials, raising their efficiency by 10–15%, while the energy consumption goes down by 8–12%. The next framework is an important step toward integrating the steps reviewed for the development of sustainable Additive Manufacturing practices. This framework overcomes the present limitations of the LCA model by introducing dynamic predictive modeling using Gaussian Process Regression, real-time adaptive decision-making through Stochastic Forest, and multi-objective optimization through Particle Swarm Optimization. This integration of the techniques in the framework would help address the real-time data and uncertainties that are inherent for adaptive and sustainable solutions in additive manufacturing processes.
Global marine modeling of CO2 hydrate stability
Variations in gamma radiation and alpha-emitting radionuclides in correlation with weather and location conditions
Abstract This research examines variations in natural radiation, focusing on terrestrial radiation and radon, in relation to weather and location. Understanding fluctuations in gamma and alpha radiation is crucial for distinguishing meteorologically-induced changes from artificial contamination. Measurements were performed hourly and daily at nine stations over the course of one year. The highest annual gamma doses were recorded in the mountain stations. The lowest gamma radiation levels and alpha-emitting radionuclide concentrations were observed in seaside regions. Precipitation influenced alpha-emitting radionuclide concentrations more than gamma radiation. Hourly variations of gamma radiation showed no consistent pattern. Statistical analysis indicated a positive correlation between gamma radiation and temperature at most locations, except near the sea where sea breezes influenced gamma dose rates. Other meteorological parameters had minimal impact on gamma radiation variations. For alpha-emitting radionuclides, a positive correlation with temperature was found, while atmospheric pressure and wind speed showed negative correlations. Seasonal variations in gamma radiation did not follow a uniform trend across all locations. In the case of seasonal variations in alpha-emitting radionuclides concentrations, the highest average values were observed during autumn and the lowest in spring.
Resveratrol attenuates hepatic oxidative stress and preserves gut mucosal integrity in high-fat diet-fed rats by modulating antioxidant and anti-inflammatory pathways
Unique nicotinic responses are present in distinct subtypes of mouse medial prefrontal layer V pyramidal neurons
Developmental transcriptomics reveals stage-specific immune gene expression profiles in Spodoptera frugiperda
2D and 3D in vitro photodynamic activities of tetra-substituted symmetric water-soluble cationic zinc(II) phthalocyanines on cancer
Causal relationships between inflammatory mediators, sleep traits, and cardiac magnetic resonance imaging-derived cardiac phenotypes
Long-distance target localization optimization algorithm based on single robot moving path planning
Understanding the trade-off and synergy effects of landscape multifunctional and its driving mechanism in rapidly urbanizing areas
Photosynthetic responses to light levels in drought-tolerant novel peanut (Arachis hypogaea L) genotypes
Abstract Drought is a significant abiotic stressor that reduces peanut production because it alters photosynthetic activity and impacts crop growth. Therefore, developing drought-tolerant peanut genotypes capable of maintaining higher photosynthetic rates (A) under stress is crucial. This study assessed changes in photosynthetic and chlorophyll fluorescence responses to light (photosynthetic photon flux density, PPFD) in newly bred drought-tolerant peanut genotypes. Ten genotypes [NM-3, NM-5, NM-6, NM-23, NM-69, NM-70, NM-74, NM-77, V-C, and C-76–16] were evaluated under full irrigation (FC100) and deficit irrigation (FC50) in a split-plot design with four replications in a greenhouse. Under high PPFD levels, genotype NM-5 with deficit irrigation exhibited significantly higher A, stomatal conductance (gs), quantum efficiency of photosystem II (ΦPSII), and electron transport rate (ETR) by 40–59%, 135–525%, 31–212%, and 31–102%, respectively, than check varieties (V-C and C-76–16) and other genotypes. The NM-74 and NM-77 genotypes also performed well under deficit irrigations but with slightly lower A, gs, ΦPSII, and ETR. Genotypes NM-5, NM-23, NM-74, and NM-77 exhibited significantly higher quantum efficiency of photosystem II (Fv’/Fm’) and photochemical quenching (qP) with higher light intensities in the daily cycle under deficit irrigation. The decline in ETR at the same PPFD levels in NM-3, NM 69, NM-70, and C-76–16 indicated photoinhibition or saturation of the photosynthetic apparatus compared to other genotypes. Concurrently, FC100 irrigation level minimizes photoinhibition, enhancing A, gs, ΦPSII, and ETR in the genotypes than FC50. Therefore, we conclude that NM-5, NM-74, and NM-77 genotypes can perform better under water deficit environments. As such, chlorophyll fluorescence parameters Fv’/Fm’ and qP can be considered for selective breeding to enhance photosynthetic efficiencies.
Coronal offset of C7 is associated with uneven joint degeneration between right and left hips after spinal fusion
Abstract The aim of the study was to investigate the effects of coronal offset of C7 after spinal fusion on the discrepancy in joint space narrowing between the right and left hips. We retrospectively reviewed data from patients who underwent lumbar spinal fusion from 2011 to 2018 at our institute. The rate of hip joint space narrowing after spinal fusion was measured in 190 patients (380 hips). We assessed the effects of the distance between the C7 plumb line and the central sacral vertical line (C7-CSVL) on the discrepancy in joint space narrowing between the right and left hips. Using multivariate regression models, we controlled for the effects of age, sex, body mass index, fusion length, and several spinopelvic alignment parameters (sacral slope, pelvic incidence, lumbar lordosis, pelvic incidence minus lumbar lordosis, and sagittal vertical axis) on the joint space narrowing rate. Multivariate regression showed that the C7-CSVL was associated with the discrepancy of the joint space narrowing rate between right and left, indicating that when C7 deviated to right, the joint space narrowing was larger in the right than left hip (standardized coefficient, 0.203; p = 0.0005). A larger C7-CSVL was associated with a larger right–left discrepancy in hip joint space narrowing after spinal fusion. These findings indicate that spinal coronal balance affects the distribution of joint degeneration in the right and left hips. Surgeons should understand the potential risk of uneven progression of degeneration between the right and left hips in patients with large coronal offset.
Wideband end-fire antenna based on modulated grooved surface plasmon polaritons
Abstract This article presents low-profile wideband millimeter-wave (mmWave) end-fire antenna based on groundless grooved spoof surface plasmon polaritons (SSPPs) technique for applications in 5G mmWave communications. A novel linearly modulated grooved profile has been designed and optimized to convert bounded SSPP modes into radiation modes. The proposed groundless modulated grooved profile is designed to achieve a zero tilting and highly directional beam in the end-fire direction. A semi-curvilinear ground profile and stepped impedance transition profile are designed to improve impedance matching, which simultaneously enable wide bandwidth of 22 GHz to 41 GHz, i.e., fractional bandwidth (FBW) of 62% with a peak gain of 13 dBi in a low-profile structure. The overall form-factor of the antenna is 5 $$\lambda _{0}$$ $$\times$$ 0.9 $$\lambda _{0}$$ $$\times$$ 0.016 $$\lambda _{0}$$ (where $$\lambda _{0}$$ is the wavelength in free space at the center frequency). The high directivity, low-profile and lightweight structure of the antenna makes it highly suitable for applications in mmWave communications.
Temporal evidence fusion evaluation method considering time sequence variation trend
Abstract Aiming at the temporal information fusion evaluation problem, a temporal evidence fusion evaluation method was proposed by considering the time sequence trend based on evidence theory to fully reflect the dynamic trend of temporal information and the influence of the time factor on fusion evaluation. Firstly, the trend of temporal evidence sequence was integrated into fusion evaluation. The temporal variation factor of the proposition was defined by analyzing the sequence of changes in evidence to measure the dynamic of the proposition. Then, conflict information between evidence was interpreted as the temporal variation information of propositions. An evidence combination rule integrating temporal variation factors of propositions was proposed in this paper. Finally, the proposed method was used to fuse and evaluate the temporal evidence. The consecutive periodic health assessment data were utilized to validate the fusion results. Numerical examples show that the discrepancy between the combined BPAs obtained using the proposed method is significantly larger, while the associated uncertainty is notably reduced. The proposed method is capable of handling conflicting information within a temporal information sequence and obtaining a reasonable fusion evaluation result by combining the temporal variation trend of propositions. It provides an idea for information fusion evaluation considering the time sequence trend.
Tang Bi formula alleviates diabetic sciatic neuropathy via AMPK/PGC-1α/MFN2 pathway activation
Abstract Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes mellitus, which affects various regions of the nervous system. Tang Bi formula (TBF) has been proven effective for DPN, while the underlying mechanism remains unclarified. This study aimed to clarifiy the neurprotective mechanism of TBF intervention in DPN through animal and cell models. UHPLC/QTOF-MS and network pharmacology analysis were utilized to identify the bioactive components and potential targets of TBF. DPN models were established in rats and Schwann cells to evaluate the therapeutic effects of TBF. In the DPN rats, body weight, fasting blood glucose, mechanical withdrawal threshold (MWT), paw withdrawal latency (PWL), sciatic motor nerve conduction velocity (MNCV), and sciatic nerve blood flow were measured. Pathological sections of the sciatic nerve (SN) were also examined. In vitro experiments, the Schwann cells (SCs) were cultured in a medium containing 30 mM glucose and treated with TBF for 48 h. Cell viability was assessed using the CCK-8 assay. The degree of apoptosis was evaluated by flow cytometry. The mitochondrial membrane potential was determined using JC—1 staining, and the generation of ROS was measured using DCFH—DA staining. Moreover, the expression levels of proteins related to the AMPK-PGC-1α-MFN2 pathway in the SN and SCs were detected. A total of 11 bioactive components of TBF were identified through UHPLC/QTOF-MS and network pharmacology analysis. In vivo experiments, MWT and PWL were decreased in DPN rats, which were restored after TBF administered daily for 12 weeks, TBF significantly attenuated thermal hyperalgesia and mechanical allodynia, and improved nerve conduction velocities. Further histopathological observations indicated that treatment with TBF promoted the regeneration of the myelin sheath of the SN, increased the density of intraepidermal nerve fibers, effectively improved distal microcirculation disorders, and alleviated demyelination and axonal degeneration. In vitro experiments were conducted to evaluate the protective effect of TBF on high-glucose-induced dysfunction of SCs. The data showed that treatment with TBF significantly inhibited the apoptosis of SCs. Meanwhile, TBF exhibited apparent antioxidant capacity, reducing the accumulation of intracellular ROS, and ameliorating mitochondrial dysfunction. Western blot analysis revealed that TBF activated the AMPK-PGC -1α-MFN2 pathway and upregulated the protein expressions of p-AMPK (Thr172), PGC-1α, and MFN2, suggesting that the neuroprotective effect of TBF was associated with the activation of this pathway. TBF ameliorated DPN by rectifying mitochondrial dynamic imbalance and modulating the activation of the AMPK-PGC-1α-MFN2 pathway. This, in turn, promoted neurogenesis and alleviated peripheral nerve lesions. Thus, this study demonstrated the therapeutic potential of TBF for DPN.