A novel fast robust optimization algorithm for intensity-modulated proton therapy with minimum monitor unit constraint.

BACKGROUND: Intensity-modulated proton therapy (IMPT) optimizes spot intensities and position, providing better conformability. However, the successful application of IMPT is dependent upon addressing the challenges posed by range and setup uncertainties. In order to address the uncertainties in IMPT, robust optimization is essential. PURPOSE: This study aims to develop a novel fast algorithm for robust optimization of IMPT with minimum monitor unit (MU) constraint. METHODS AND MATERIALS: The study formulates a robust optimization problem and proposes a novel, fast algorithm based on the alternating direction method of multipliers (ADMM) framework. This algorithm enables distributed computation and parallel processing. Ten clinical cases were used as test scenarios to evaluate the performance of the proposed approach. The robust optimization method (RBO-NEW) was compared with plans that only consider nominal optimization using CTV (NMO-CTV) without handling uncertainties and PTV (NMO-PTV) to handle the uncertainties, as well as with conventional robust-optimized plans (RBO-CONV). Dosimetric metrics, including D95, homogeneity index, and Dmean, were used to evaluate the dose distribution quality. The area under the root-mean-square dose (RMSD)-volume histogram curves (AUC) and dose-volume histogram (DVH) bands were used to evaluate the robustness of the treatment plan. Optimization time cost was also assessed to measure computational efficiency. RESULTS: The results demonstrated that the RBO plans exhibited better plan quality and robustness than the NMO plans, with RBO-NEW showing superior computational efficiency and plan quality compared to RBO-CONV. Specifically, statistical analysis results indicated that RBO-NEW was able to reduce the computational time from 389.70 ± 207.40 $389.70\pm 207.40$ to 228.60 ± 123.67 $228.60\pm 123.67$ s ( p < 0.01 $p<0.01$ ) and reduce the mean organ-at-risk (OAR) dose from 9.38 ± 12.80 $9.38\pm 12.80$ % of the prescription dose to 9.07 ± 12.39 $9.07\pm 12.39$ % of the prescription dose ( p < 0.05 $p<0.05$ ) compared to RBO-CONV. CONCLUSION: This study introduces a novel fast robust optimization algorithm for IMPT treatment planning with minimum MU constraint. Such an algorithm is not only able to enhance the plan's robustness and computational efficiency without compromising OAR sparing but also able to improve treatment plan quality and reliability.

Proton spot dose estimation based on positron activity distributions with neural network.

BACKGROUND: Positron emission tomography (PET) has been investigated for its ability to reconstruct proton-induced positron activity distributions in proton therapy. This technique holds potential for range verification in clinical practice. Recently, deep learning-based dose estimation from positron activity distributions shows promise for in vivo proton dose monitoring and guided proton therapy. PURPOSE: This study evaluates the effectiveness of three classical neural network models, recurrent neural network (RNN), U-Net, and Transformer, for proton dose estimating. It also investigates the characteristics of these models, providing valuable insights for selecting the appropriate model in clinical practice. METHODS: Proton dose calculations for spot beams were simulated using Geant4. Computed tomography (CT) images from four head cases were utilized, with three for training neural networks and the remaining one for testing. The neural networks were trained with one-dimensional (1D) positron activity distributions as inputs and generated 1D dose distributions as outputs. The impact of the number of training samples on the networks was examined, and their dose prediction performance in both homogeneous brain and heterogeneous nasopharynx sites was evaluated. Additionally, the effect of positron activity distribution uncertainty on dose prediction performance was investigated. To quantitatively evaluate the models, mean relative error (MRE) and absolute range error (ARE) were used as evaluation metrics. RESULTS: The U-Net exhibited a notable advantage in range verification with a smaller number of training samples, achieving approximately 75% of AREs below 0.5 mm using only 500 training samples. The networks performed better in the homogeneous brain site compared to the heterogeneous nasopharyngeal site. In the homogeneous brain site, all networks exhibited small AREs, with approximately 90% of the AREs below 0.5 mm. The Transformer exhibited the best overall dose distribution prediction, with approximately 92% of MREs below 3%. In the heterogeneous nasopharyngeal site, all networks demonstrated acceptable AREs, with approximately 88% of AREs below 3 mm. The Transformer maintained the best overall dose distribution prediction, with approximately 85% of MREs below 5%. The performance of all three networks in dose prediction declined as the uncertainty of positron activity distribution increased, and the Transformer consistently outperformed the other networks in all cases. CONCLUSIONS: Both the U-Net and the Transformer have certain advantages in the proton dose estimation task. The U-Net proves well suited for range verification with a small training sample size, while the Transformer outperforms others at dose-guided proton therapy.

Fish Oil, Plasma n-3 PUFAs, and Risk of Macro- and Microvascular Complications among Individuals with Type 2 Diabetes.

OBJECTIVE: To evaluate associations of fish oil supplementation and plasma omega 3 polyunsaturated fatty acids (n-3 PUFAs) with risks of macrovascular and microvascular complications among people with type 2 diabetes, and to further explore the potential mediating role of metabolism-related biomarkers. RESEARCH DESIGN AND METHODS: This study included 20,338 participants with type 2 diabetes from UK Biobank. Diabetic complications were identified through hospital inpatient records. RESULTS: During 13.2 years of follow-up, 5,396 people developed macrovascular complications, and 4,868 people developed microvascular complications. After multivariable adjustment, hazard ratios (HRs) and 95% confidence intervals (CIs) for patients with fish oil were 0.90 (0.85, 0.97) for composite macrovascular complications, 0.91 (0.84, 0.98) for coronary heart disease (CHD), 0.72 (0.61, 0.83) for peripheral artery disease; and 0.89 (0.83, 0.95) for composite microvascular complications, 0.87 (0.79, 0.95) for diabetic kidney disease, and 0.88 (0.80, 0.97) for diabetic retinopathy. In addition, higher n-3 PUFA levels, especially docosahexaenoic acid (DHA), were associated with lower risks of macrovascular and microvascular complications. Comparing extreme quartiles of plasma DHA, the HRs (95% CIs) were 0.68 (0.57, 0.81) for composite macrovascular complications, 0.63 (0.51, 0.77) for CHD; and 0.59 (0.38, 0.91) for diabetic neuropathy. Moreover, biomarkers including lipid profile and inflammation collectively explained 54.4% and 63.1% of associations of plasma DHA with risks of composite macrovascular complications and CHD. CONCLUSIONS: Habitual use of fish oil supplementation and higher plasma n-3 PUFA levels, especially DHA, were associated with lower risks of macrovascular and microvascular complications among individuals with type 2 diabetes, and the favorable associations were partially mediated through improving biomarkers of lipid profile and inflammation.

Traceability and policy suggestions for ozone pollution in heavy industrial city in Northeast China.

In the heavy industrial city of Northeast China, there has been a significant decrease in particulate matter pollution while experiencing a sharp increase in ozone (O3) pollution. However, the main influencing factors and source contributions to O3 remain unclear. Taking the case of Siping as an example, this study analyzed the spatiotemporal characteristics, assessed local source contributions to O3, and revealed regional transmission effects using numeric simulation and statistical methods. Temporally, higher O3 concentrations were observed in summer and the afternoon, with hourly peaks up to 254 µg/m3. Spatially, O3 pollution was mainly contributed by background concentrations (34.52%), external transport (34.50%), and local emissions (30.98%) during the case study period (June 11-18, 2021). Among the local emission sources, biological emissions, the industrial sector, and the traffic sector accounted for 35.30%, 32.09%, and 23.58% of the O3 concentration, respectively. For regional atmospheric transmission, high O3 pollution was accompanied by wind from the southwest directions, and the trajectory of air mass transport suggests that eastern Mongolia, the Korean Peninsula, and its neighboring regions contribute to O3 pollution. Furthermore, sensitivity analysis showed that O3 pollution in Siping is a co-controlled region by anthropogenic volatile organic compounds (AVOCs) and NOX, which implies control in an optimal ratio of VOCs and NOX emissions. Thus, our results highlight the importance of joint prevention and control of O3 pollution in the region, optimization of biogenic landscape ecology, and control of VOCs and NOx in both the industrial and transport sectors.

Salinity-Induced Variations in Bacterial Composition and Co-occurrence Patterns within Salicornia-Based Constructed Wetlands in Mariculture.

Constructed wetlands use vegetation and microorganisms to remove contaminants like nitrogen and phosphorus from water. For mariculture, the impact of salinity on the efficiency of wastewater treatment of wetlands is unneglectable. However, little is known about their impact on the microbiome in constructed wetlands. Here, we set four salinity levels (15, 22, 29, and 36) in Salicornia constructed wetlands, and the experiment was conducted for a period of 72 days. The 15 group exhibited the highest removal rates of nitrogen compounds and phosphate, compared to the other salinity groups, the nosZ gene exhibited significantly higher expression in the 22 group (p < 0.05), indicated that microorganisms in 22 salinity have higher denitrification abilities. The three dominant phyla identified within the microbiomes were Proteobacteria, known for their diverse metabolic capabilities; Cyanobacteria, important for photosynthesis and nitrogen fixation; and Firmicutes, which include many fermenters. The ecological network analysis revealed a 'small world' model, characterized by high interconnectivity and short path lengths between microbial species, and had higher co-occurrence (45.13%) observed in this study comparing to the Erdös-Réyni random one (32.35%). The genus Microbulbifer emerged as the sole connector taxon, pivotal for integrating different microbial communities involved in nitrogen removal. A negative correlation was observed between salinity levels and network complexity, as assessed by the number of connections and diversity of interactions within the microbial community. Collectively, these findings underscore the critical role of microbial community interactions in optimizing nitrogen removal in constructed wetlands, with potential applications in the design and management of such systems for improved wastewater treatment in mariculture.

The Gut Microbial Regulation of Epigenetic Modification from a Metabolic Perspective.

Obesity is a global health challenge that has received increasing attention in contemporary research. The gut microbiota has been implicated in the development of obesity, primarily through its involvement in regulating various host metabolic processes. Recent research suggests that epigenetic modifications may serve as crucial pathways through which the gut microbiota and its metabolites contribute to the pathogenesis of obesity and other metabolic disorders. Hence, understanding the interplay between gut microbiota and epigenetic mechanisms is crucial for elucidating the impact of obesity on the host. This review primarily focuses on the understanding of the relationship between the gut microbiota and its metabolites with epigenetic mechanisms in several obesity-related pathogenic mechanisms, including energy dysregulation, metabolic inflammation, and maternal inheritance. These findings could serve as novel therapeutic targets for probiotics, prebiotics, and fecal microbiota transplantation tools in treating metabolic disruptions. It may also aid in developing therapeutic strategies that modulate the gut microbiota, thereby regulating the metabolic characteristics of obesity.

Paradoxical cognitive and language function recovery by zolpidem in a patient with traumatic brain injury: A case report.

BACKGROUND: Traumatic brain injury (TBI) is a significant public health issue, often resulting from traffic accidents and falls, leading to a wide spectrum of outcomes from mild concussions to severe brain damage. The neurorehabilitation of TBI focuses on enhancing recovery and improving quality of life. Zolpidem, traditionally used for short-term management of insomnia, has shown potential in improving cognitive functions and language in TBI patients. Advances in neuroimaging techniques, such as functional near-infrared spectroscopy (fNIRS), have facilitated the exploration of the effects of therapeutic interventions on brain activity and functional connectivity in TBI patients. CASE SUMMARY: We present the case of a 34-year-old male who sustained a TBI from a traffic collision. Despite severe impairments in cognitive and language functions, administration of 10 mg of zolpidem resulted in temporary but significant improvements in these areas, as evidenced by increased Mini-Mental State Examination scores and observed behavioral changes. fNIRS assessments before and after zolpidem administration revealed notable changes in cerebral cortex activity, including increased left hemisphere activation and a shift in functional connectivity to the bilateral frontal lobes, corresponding with the patient's improvement. CONCLUSION: This case study highlights the potential of zolpidem, a medication traditionally used for insomnia, in enhancing cognitive and verbal functions in a patient with TBI, suggesting a potential therapeutic role for zolpidem in neurorehabilitation, supported by changes in brain activity and connectivity observed through fNIRS. However, further investigation is warranted to validate these findings and elucidate zolpidem's long-term effects on cognitive and functional outcomes in TBI patients.

[Simultaneous determination of maltol and seventeen saponins in red and black ginseng by UPLC-PDA wavelength switching method].

This study developed a UPLC-PDA wavelength switching method to simultaneously determine the content of maltol and seventeen saponins in red and black ginseng and compared the quality differences of two different processed products of red and black ginseng. A Waters HSS T3 column(2. 1 mm×100 mm, 1. 8 µm) at 30 ℃ was adopted, with the mobile phase of acetonitrile(A) and water containing 0. 1% phosphoric acid(B) under gradient elution, the flow rate of 0. 3 m L·min~(-1), and the injection volume of 2 µL.The wavelength switching was set at 273 nm within 0-11 min and 203 nm within 11-60 min. The content results of multiple batches of red and black ginseng samples were analyzed by the hierarchical cluster analysis(HCA) and principal component analysis(PCA) to evaluate the quality difference. The results showed that the 18 constituents exhibited good linear relationships within certain concentration ranges, with the correlation coefficients(r) greater than 0. 999 1. The relative standard deviations(RSDs) of precision,repeatability, and stability were all less than 5. 0%. The average recoveries ranged from 95. 93% to 104. 2%, with an RSD of 1. 8%-4. 2%. The content determination results showed that the quality of red and black ginseng samples was different, and the two types of processed products were intuitively distinguished by HCA and PCA. The method is accurate, reliable, and reproducible. It can be used to determine the content of maltol and seventeen saponins in red and black ginseng and provide basic information for the quality evaluation and comprehensive utilization of red and black ginseng.

Processing and Utilization Technology of Root and Tuber Food.

Roots and tubers make a great contribution to major staple foods and provide good sources of dietary carbohydrates for the nutrition supply and energy recharge of human [...].

Advances in the Anti-Atherosclerotic Mechanisms of Epigallocatechin Gallate.

Atherosclerosis (AS) is a common clinical sickness and the major pathological basis of ischemic cardiocerebrovascular diseases (CCVDs). The pathogenesis of AS involves a variety of risk factors, and there is a lack of effective preventive and curative drugs that can completely treat AS. In recent years, with the improvement of people's living standards and changes in dietary habits, the morbidity and mortality rates of AS are on the rise, and the age of onset tends to be younger. The formation of AS is closely related to a variety of factors, and the main factors include lipid metabolism disorders, endothelial damage, inflammation, unstable plaques, etc. Epigallocatechin gallate (EGCG), as one of the main components of catechins, has a variety of pharmacological effects, and its role in the prevention of AS and the protection of cardiovascular and cerebral blood vessels has been highly valued. Recent epidemiological investigations and various in vivo and ex vivo experiments have shown that EGCG is capable of resisting atherosclerosis and reducing the morbidity and mortality of AS. In this paper, we reviewed the anti-AS effects of EGCG and its mechanisms in recent years, including the regulation of lipid metabolism, regulation of intestinal flora disorders, improvement of vascular endothelial cell functions, inhibition of inflammatory factors expression, regulation of inflammatory signaling pathways, inhibition of matrix metalloproteinase (MMP) expression, and inhibition of platelet aggregation, which are helpful for the prevention of cardiocerebrovascular diseases.

Association of the hemoglobin, albumin, lymphocyte, and platelet score with the risk of Erectile dysfunction: a cross-sectional study.

Erectile dysfunction (ED) is related to nutritional and inflammatory factors. The hemoglobin, albumin, lymphocyte, and platelet score (HALP), a new index reflecting the nutritional and inflammatory status, has been associated with a higher risk of diabetic retinopathy, particularly at lower values (≤ 42.9). However, studies focusing on the relationship between HALP and ED risk are scarce. Hence, this study aimed to investigate the association between HALP and ED. Data were extracted from the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2004. Based on self-reported data, participants were classified into either the ED group or the non-ED group. Next, the HALP score was categorized into four quartiles (Q1-4). Weighted multivariate regression analysis was performed to assess the relationship between categorical HALP and ED risk. Additionally, restricted cubic spline (RCS) analysis was conducted to examine the association between continuous HALP scores and ED risk. Furthermore, subgroup analyses were conducted to examine the association between categorical HALP and the risk of ED based on age, as well as the status of hypertension, diabetes and cardiovascular disease. Finally, a mediation analysis was carried out to investigate the mediating effect of HALP and related parameters on the association between urinary cobalt levels and ED. Initially, the data of 21,161 participants were collected. After implementing the inclusion and exclusion criteria, 3406 participants were included in the final analyses. Weighted multivariate regression analysis demonstrated that the Q4 HALP group was associated with a lower risk of ED (OR 0.96, 95% confidence intervals 0.92-1.00, P = 0.037). Meanwhile, RCS analysis showed that HALP was nonlinearly associated with the risk of ED. In addition, subgroup analyses demonstrated that participants in the Q3/4 HALP group had a significantly lower ED risk than those in the Q1 group among patients aged ≥ 50 years, as well as those with hypertension and diabetes. Lastly, mediation analysis revealed that HALP and its associated parameters had a marginal average causal mediation effect on the relationship between urinary cobalt levels and ED risk (P > 0.05). In US adults, high HALP scores were correlated with a lower risk of ED. The relationship was more pronounced in participants aged ≥ 50 years with hypertension and diabetes. Furthermore, HALP and its parameters may not mediate the association between urinary cobalt levels and ED risk.

Learning Molecular Representation in a Cell.

Predicting drug efficacy and safety in vivo requires information on biological responses (e.g., cell morphology and gene expression) to small molecule perturbations. However, current molecular representation learning methods do not provide a comprehensive view of cell states under these perturbations and struggle to remove noise, hindering model generalization. We introduce the Information Alignment (InfoAlign) approach to learn molecular representations through the information bottleneck method in cells. We integrate molecules and cellular response data as nodes into a context graph, connecting them with weighted edges based on chemical, biological, and computational criteria. For each molecule in a training batch, InfoAlign optimizes the encoder's latent representation with a minimality objective to discard redundant structural information. A sufficiency objective decodes the representation to align with different feature spaces from the molecule's neighborhood in the context graph. We demonstrate that the proposed sufficiency objective for alignment is tighter than existing encoder-based contrastive methods. Empirically, we validate representations from InfoAlign in two downstream tasks: molecular property prediction against up to 19 baseline methods across four datasets, plus zero-shot molecule-morphology matching.

Disorder of consciousness related pattern could distinguish minimally conscious state from unresponsive wakefulness syndrome: A F-18-FDG-PET study.

BACKGROUND: Accurate evaluation of level of disorder of consciousness (DOC) is clinically challenging. OBJECTIVE: This study aimed to establish a distinctive DOC-related pattern (DOCRP) for assessing disease severity and distinguishing unresponsive wakefulness syndrome (UWS) from minimally conscious state (MCS). METHODS: Fifteen patients with DOC and eighteen health subjects with F-18-fluorodeoxyglucose (F-18-FDG) positron emission tomography (PET) were enrolled in this study. All patients were assessed by Coma Recovery Scale-Revised (CRS-R) and all individuals were randomly divided into two cohorts (Cohort A and B). DOCRP was identified in Cohort A and subsequently validated in Cohort B and A+B. We also assessed the discriminatory power of DOCRP between MCS and UWS. RESULTS: The DOCRP was characterized bilaterally by relatively decreased metabolism in the medial and lateral frontal lobes, parieto-temporal lobes, cingulate gyrus and caudate, associated with relatively increased metabolism in the cerebellum and brainstem. DOCRP expression exhibited high accuracy in differentiating DOC patients from controls (P<0.0001, AUC=1.000), and furthermore could effectively distinguish MCS from UWS (P=0.037, AUC=0.821, sensitivity: 85.7 %, specificity: 75.0 %). Particularly in the subgroup of DOC patients survived global hypoxic-ischemic brain injury, DOCRP expression exhibited even better discriminatory power between MCS and UWS (P=0.046, AUC=1.000). CONCLUSIONS: DOCRP might serve as an objective biomarker in distinguishing between UWS and MCS, especially in patients survived global hypoxic-ischemic brain injury. TRIAL REGISTRATION NUMBER: ChiCTR2300073717 (Chinese clinical trial registry site, http://www.chictr.org).

Different antithrombotic strategies after coronary artery bypass grafting to prevent adverse events: a retrospective analysis.

OBJECTIVE: Coronary artery bypass grafting (CABG) is associated with antithrombotic therapy in terms of postoperative adverse events; however, it is still unknown whether the early use of such drugs after CABG is safe and effective. In this study, we aim to evaluate the relationship between different postoperative antithrombotic strategies and in-hospital adverse events in patients undergoing isolated coronary artery bypass grafting surgery. METHODS: This was a single-center, retrospective cohort analysis of patients undergoing isolated CABG due to coronary artery disease (CAD) between 2001 and 2012. Data were extracted from the Medical Information Mart for Intensive Care III database. The patients involved were divided into the ASA (aspirin 81 mg per day only) or DAPT (aspirin plus clopidogrel 75 mg per day) group according to the antiplatelet strategy. Patients were also stratified into subgroups based on the type of anticoagulation. The in-hospital risk of bleeding and adverse events was investigated and compared between groups. Propensity score matching (PSM) was performed to reduce the potential effects of a selection bias. RESULTS: A total of 3274 patients were included in this study, with 2358 in the ASA group and 889 in the DAPT group. Following the PSM, no significant difference was seen in the risk of major bleeding between the two groups according to the PLATO, TIMI or GUSTO criteria. There was no difference in the postoperative mortality. In subgroup analysis, patients given anticoagulant therapy had an increased incidence of bleeding-related events. Multivariable analysis revealed that postoperative anticoagulant therapy and the early use of heparin, but not DAPT, were independent predictors of bleeding-related events. CONCLUSIONS: Postoperative DAPT was not associated with an increased occurrence of bleeding-related events in patients undergoing isolated CABG and appears to be a safe antiplatelet therapy. The addition of anticoagulants to antiplatelet therapy increased the risk of bleeding and should be considered cautiously in clinical practice.

Adherence to a planetary health diet, genetic susceptibility, and incident cardiovascular disease: a prospective cohort study from the UK Biobank.

BACKGROUND: The influence of adherence to a planetary health diet (PHD) proposed by the EAT-Lancet Commission on cardiovascular disease (CVD) is inconclusive. Besides, whether genetic susceptibility to CVD can modify the association of PHD with CVD remains unknown. OBJECTIVE: We aimed to investigate the association between adherence to PHD and CVD, and to evaluate the interaction between PHD and genetic predisposition to CVD. METHODS: This study included 114,165 participants who completed at least two 24-h dietary recalls and were initially free of CVD from the UK Biobank. PHD score was calculated to assess adherence to PHD. Genetic risk was evaluated using the polygenic risk score. Incidence of total CVD, ischemic heart disease (IHD), atrial fibrillation (AF), heart failure (HF), and stroke were identified via electronic health records. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During a median follow-up of 9.9 y, 10,071 (8.8%) incident CVD cases were documented. Compared with participants with the lowest adherence to PHD, HRs (95% CIs) for total CVD, IHD, AF, HF, and stroke among those with the highest adherence were 0.79 (0.74, 0.84), 0.73 (0.67, 0.79), 0.90 (0.82, 0.99), 0.69 (0.59, 0.82), and 0.88 (0.75, 1.04), respectively. No significant interaction between the genetic risk of CVD and PHD was observed. Participants with high genetic risk and low PHD score, as compared with those with low genetic risk and high PHD score, had a 48% (95% CI: 40%, 56%) higher risk of CVD. The population-attributable risk (95% CI) of CVD for poor adherence to PHD ranged from 8.79% (5.36%, 12.51%) to 14.00% (9.00%, 18.88%). CONCLUSIONS: These findings suggest that higher adherence to PHD was associated with lower risk of total CVD, IHD, AF, and HF in populations across all genetic risk categories.

Deuterium Editing of Small Molecules: A Case Study on Antitumor Activity of 1,4-Benzodiazepine-2,5-dione Derivatives.

Substituting hydrogen with deuterium in drug molecules is an appealing bioisosteric strategy for the generation of novel chemical entities in drug development. Optimizing lead compounds through deuteration has proven to be challenging and unpredictable, particularly for compounds with multiple metabolic sites. This study presents the pioneering achievement of substituting up to 19 hydrogen atoms with deuterium on 1,4-benzodiazepine-2,5-dione derivatives, shedding light on the structure-metabolism relationship and the impact of multiple deuterations on drug-like properties. Notably, the deuterated compound 3f exhibited remarkable antitumor activity in vivo and demonstrated favorable drug-like properties as a drug candidate.

Detecting localized damage in cantilevered structures under nonstationary ambient excitations via Gabor spectral mode transmissibility functions.

A method based on Gabor spectral mode transmissibility functions (GSMTFs) is proposed to detect local damage in a cantilevered structure under nonstationary ambient excitations. Gabor transformation and singular value decomposition are used to reduce the influences of other vibration modes on Gabor spectral mode transmissibility functions and process nonstationary structural responses, respectively. A new state characteristic based on the fundamental structure frequency is formulated on the basis of the GSMTFs, eventually leading to the development of a new damage indicator. The probability density functions of the damage indicator for healthy and damaged states can be estimated from the measured data, and the receiver operating characteristic (ROC) curve derived from these probability distributions and the corresponding area under the ROC curve (AUC) are used to determine the damage location. A six-degree-of-freedom system and a typical transmission tower are numerically studied, and the results show that the proposed method can estimate the structural damage location under nonstationary random loads. The proposed method is further validated with a planar frame in the laboratory, which exhibits multiple damage elements via random force hammer excitations. The results show that the AUC values computed for certain parts of the structure containing the damaged elements are greater than those for other parts of the structure, indicating the effectiveness of the proposed method. Moreover, the proposed method is compared with the dot product difference (DPD) index, and the results from the laboratory planar frame demonstrate that the proposed method can better identify damage.

Flexible Multimodal Sensors Enhanced by Electrospun Lead-Free Perovskite and PVDF-HFP Composite Form-Stable Mesh Membranes for In Situ Plant Monitoring.

The pH and humidity of the crop environment are essential indicators for monitoring crop growth status. This study reports a lead-free perovskite/polyvinylidene fluoride-hexafluoropropylene composite (LPPC) to enhance the stability and reliability of in situ plant pH and humidity monitoring. The mesh composite membrane of LPPC illustrates a hydrophobic contact angle of 101.982°, a tensile strain of 800%, and an opposing surface potential of less than -184.9 mV, which ensures fast response, high sensitivity, and stability of the sensor during long-term plant monitoring. The LPPC-coated pH electrode possesses a sensitivity of -63.90 mV/pH, which provides a fast response within 5 s and is inert to environmental temperature interference. The LPPC-coated humidity sensor obtains a sensitivity of -145.7 Ω/% RH, responds in 28 s, and works well under varying light conditions. The flexible multimodal sensor coated with an LPPC membrane completed real-time in situ monitoring of soilless strawberries for 17 consecutive days. Satisfactory consistency and accuracy performance are observed. The study provides a simple solution for developing reliable, flexible wearable multiparameter sensors for in situ monitoring of multiple parameters of crop environments.

Evaluation of hydrochar-derived modifier and water-soluble fertilizer on saline soil improvement and pasture growth.

Soil salinization poses a serious threat to crop growth. The selection of appropriate soil modifiers and water-soluble fertilizers for saline soils represents a crucial method for enhancing crop yields. The modifiers and medium-element water-soluble fertilizers were prepared using hydrochar derived from rice straw. Two distinct experiments were designed to study the effect of modifiers and water-soluble fertilizers on saline soils. The first experiment, designated as the "Soil Cultivation Experiment" , sought to investigate the impact of various modifiers on soil quality. The second experiment, designated as the "Method of Field Micro-Area Experiment", aimed to assess the influence of water-soluble fertilizers on saline soils. The results showed that the application of modifiers and water-soluble fertilizers significantly enhanced comprehensive soil physical and chemical properties, crop growth, soil enzyme activity, and other key indicators in saline and alkaline soils. The optimal dosage of the modifier was 20 g/kg, which reduced the pH value from 8.62 to 8.21 and the decreased alkalinity by 8.26%. Furthermore, their application effectively boosted nutrient levels, including organic matter, and increased soil enzyme activity. The biomass of alfalfa showed enhancements of 63.01% and 20.87% and the biomass of leymus chinensis increased by 29.39% and 9.02% for the two batches, respectively. Notably, the application of water-soluble fertilizer yielded achieved superior results. This study also provided a theoretical basis for their future application in soda saline-alkali soil.

Investigation on the cavitation characteristic of a novel cylindrical rotational hydrodynamic cavitation reactor.

Hydrodynamic cavitation reactors are of great promise for the applications of chemical process intensification and water treatment. In this work, a novel cylindrical rotational hydrodynamic cavitation reactor (CRHCR) with rectangular grooves and oblique tooth protrusions on the rotor surface was studied. The three-dimensional characterization of cavitation within the CRHCR was observed from the front and left views by the high-speed camera experiments. Interestingly, a new phenomenon of simultaneous formation of the attached cavitation and shear cavitation was found in the CRHCR. The synergistic effect of attached cavitation and shear cavitation contributes to the enhancement of the cavitation performance of CRHCR. In addition, the evolution of attached cavitation is explored. It is found that attached cavitation forms a trapezoidal-shaped cavitation cloud in the groove, which undergoes three various stages: incipient, development, and collapse. Finally, the pulsation frequency and cavitation intensity of shear cavitation in the chamber were investigated. The results show that the cavitation pulsation frequency is the same at the same rotational speed in the chamber near diverse oblique teeth. As the rotational speed increases, the cavitation pulsation frequency increases linearly. These findings in this paper are of great benefit to understanding the mechanism of the cavitation effect of CRHCR.