Reduction In Capacity Research Articles

Cardiac Hemodynamics, Tissue Oxygenation, and Functional Capacity in Post-COVID-19 Patients

Background and Objectives: This study aimed to evaluate and compare the functional capacity of post-COVID-19 patients with a control group and analyze cardiac hemodynamics and muscle tissue oxygenation responses during assessment protocols in both groups. Materials and Methods: A cross-sectional study was conducted involving patients with COVID-19 and a control group who were all aged ≥18 years. Participants underwent two functional capacity tests: the one-minute sit–stand test (1-STS) and the six-minute walk test (6MWT). Cardiac hemodynamic responses were evaluated using impedance during the 1-STS, and tissue perfusion responses in the oxygenation were recorded during and after both tests. The Friedman test was used for within-group and the Mann–Whitney test was used for between-group comparisons. Results: Thirty-six post-COVID-19 patients (median age 36 years, BMI 26.51 kg/m2) and eleven control subjects (median age 25 years, BMI 23.71 kg/m2) were enrolled. The post-COVID-19 group showed a 20% decrease in 6MWT distance (p = 0.0001) and a 28% decrease in 1-STS repetitions (p = 0.01) versus the control group. Cardiac hemodynamic differences were observed in the post-COVID-19 group during the 1-STS, with reductions in the stroke volume index (18%, p = 0.004), cardiac index (21%, p = 0.0009), Contractility Index (78%, p = 0.0001), and Ejection Fraction (29%, p = 0.0003) and increases in Systemic Vascular Resistance (25%, p = 0.03) and the Systemic Vascular Resistance Index (27%, p = 0.0007). Tissue oxygenation during the 6MWT and 1-STS showed no significant differences between groups. Conclusions: The post-COVID-19 subjects exhibited a reduction in functional capacity, changes in hemodynamic responses related to cardiac and systemic vascular resistance, and a similar pattern of muscle oxygen delivery and consumption in both tests

An Adsorbent for Efficient and Rapid Gold Recovery from Solution: Adsorption Properties and Mechanisms.

Adsorption is an efficient and highly selective method for gold recovery. Introducing rich N/S organic groups to combine with metal-organic frameworks (MOFs) as adsorbents is regarded as a practical and efficient approach to enhance gold recovery. Herein, a MOF (zirconium isothiocyanatobenzenedicarboxylate MOF, UiO-66-NCS) was designed to combine with amidinothiourea (AT) to form UiO-66-AT (zirconium amidothiourea-benzenedicarboxylate MOF) for efficient and rapid adsorption. The prepared UiO-66-AT delivers an improved adsorption capacity (about 903.02 mg/g at 1000 mg·L-1 of the initial Au3+) and an impressive adsorption rate within minutes (about 10 min for 200 mg·L-1 Au3+). Meanwhile, it exhibits sustainable stability after 5 cycles with a retention rate of 99.52% and excellent adsorption selectivity of 98.76% in actual wastewater. According to advanced characterizations and Density Functional Theory (DFT) simulation, the mechanism might be elaborated as electrostatic adsorption, chelating coordination, and chemical reduction. The modified active groups of the MOF provide the adsorption sites for Au(III) and the rapid reduction of Au(0). UiO-66-AT maintains a large adsorption capacity and high surface reduction activity while realizing stable application in multiple cycles, which is of good practical application value.

REBCO coated conductors: enabling the next generation of tokamak reactors

Abstract The discovery of REBCO (rare-earth barium copper oxide) materials with high critical temperatures, and the continued advancements in the fabrication of REBCO coated conductors with extremely high critical current densities, has enabled the development of ultra-high-field (> 20 T) compact and large-scale thermonuclear fusion devices. At present, around a dozen global commercial manufacturers are able to supply high-quality REBCO coated conductors with excellent performance. Significant advancements have been made for high-temperature, low-field applications such as motors, generators, long-length transmission cables, and so on using REBCO coated conductors. Nonetheless, multiple ongoing critical challenges under low-temperature, high-field conditions, such as irreversible degradation of the critical current, along with insufficient mechanical protection and inadequate reduction of AC losses, remain unsolved, collectively hindering their utilization in high-field thermonuclear fusion reactors. This paper provides a comprehensive theoretical and technical review of the current state-of-the-art, associated challenges, and prospects in the research and development (R&D) of REBCO coated conductors, cables, and magnet systems for high-field fusion. It highlights the significant enhancements in current-carrying capacity, mechanical protection, and AC loss reduction achieved over the past decade. The paper delves into detailed analyses of potential cabling solutions that offer exceptional current-carrying capacity while ensuring an optimal inductance balance for toroidal, poloidal, and central solenoid coils in tokamak devices. This work endeavors to lay the groundwork for the R&D of the next-generation REBCO magnets to facilitate the construction of ultra-high-field compact and large-scale tokamak reactors.

Implications of climate‐smart agriculture technology adoption on women's productivity and food security in Tanzania

AbstractGender gaps in productivity and food security persist in the face of climate change, necessitating effective strategies for empowering women and reducing their vulnerability. This study examines the gender‐specific impacts of climate‐smart agriculture (CSA) adoption on productivity, food security, and resilience to climate shocks in Tanzania. Using panel data from the World Bank's Tanzanian Living Standard Measurement Survey (LSMS) spanning 2008–2013, we employ a multinomial switching regression model (MSRM) approach to identify the effects of CSA adoption on agricultural outcomes. Our findings reveal that CSA non‐adoption exacerbates the gender gap in yields and food security, favoring men. However, CSA adoption leads to more equitable outcomes, bridging the gender gap and improving productivity and food security for both men and women. Additionally, adopters of CSA techniques exhibit greater resilience to climate shocks, experiencing smaller yield declines during periods of low rainfall. This study contributes to the literature by providing empirical evidence on the gendered impacts of CSA adoption, testing the risk reduction capacity of CSA technologies, and addressing the limited research on Tanzania. The findings emphasize the importance of gender‐responsive CSA policies in promoting agricultural resilience and food security in the face of climate change.

Waste control by waste: Metals recovery from electroplating sludge via a chlorination roasting followed by silicothermic reduction using solar-grade silicon cutting waste.

Electroplating sludge (ES) is a hazardous waste, because it contains heavy metals. It poses severe environmental and health risk if not properly disposed. This study proposed a combined pyro-metallurgical process to separate and recover copper, nickel, chromium and iron from it. A chlorination roasting was firstly used to selectively recover copper and nickel, in which they were chlorinated and volatilized while chromium and iron retained in the residue in the forms of FeCr2O4 and Fe2O3. A certain FeS2 promoted the conversion of the chlorinating agent of NaClO to Cl2 (g), increasing the copper and nickel chlorination. Though Cr2S3 could be chlorinated and volatilized, a high O2 partial pressure oxidized it to Cr2O3 and reduced it chlorination. Under the optimal condition, the chlorination of copper and nickel obtained 99.1% and 92.6% respectively, while that of chromium was only 5.7%. In the followed silicothermic reduction, a silicon cutting waste (Si-CW) was employed as reductant to recover chromium and iron from the roasted residue, due to the reduction capacity of Si and SiC phases in it. The chromium and iron oxides were reduced and recycled in an Fe-Cr alloy ingot, and Si and SiC changed to a refractory SiO2 and entered into the slag. CaO could be slagged with SiO2 and converted to a slag-liquid phase, which accelerated the separation between alloy and slag. The chromium and iron yields could obtain 97.6% and 98.9%, respectively. This study supplied a new method to co-treat two wastes for recovering nickel, iron, copper and chromium.

The blood pressure lowering effect of beetroot juice is impaired in periodontitis and recovered after periodontal treatment

We have previously demonstrated that subgingival levels of nitrate-reducing bacteria, as well as the in vitro salivary nitrate reduction capacity (NRC), were diminished in periodontitis patients, increasing after periodontal treatment. However, it remains unclear if an impaired NRC in periodontitis can affect systemic health. To determine this, the effect of nitrate-rich beetroot juice (BRJ) on blood pressure was determined in 15 periodontitis patients before and 70 days after periodontal treatment (i.e., professional mechanical plaque removal, oral hygiene instruction, and subgingival instrumentation), as well as in a healthy control group of 15 individuals. Additionally, subgingival and tongue samples were taken to analyse the bacterial composition with Illumina sequencing of the 16S rRNA gene. In healthy individuals, the systolic and diastolic blood pressure (SBP and DPB) decreased significantly (both P < 0.01) 90 min after BRJ intake, but not in periodontitis patients. However, after periodontal treatment, this blood pressure-lowering effect was recovered (P < 0.05 for SBP; P < 0.01 for DBP). Lower levels of salivary nitrate after identical doses of BRJ intake indicated a potentially higher NRC in healthy individuals (P < 0.05). Periodontitis-associated bacteria decreased in tongue and subgingival samples after periodontal treatment (P < 0.01). In contrast, nitrate-reducing bacteria were associated with health in both habitats, but increased only in subgingival plaque after periodontal treatment (P < 0.001). This is the first study showing that periodontitis could limit the blood-pressure lowering effects of nitrate reduction by the oral microbiota. We propose that an impaired NRC represents a potential link between periodontitis and systemic conditions, which should be confirmed in future randomized controlled trials. Future work should also aim to determine if nitrate prebiotic supplementation and/or tongue cleaning could improve the treatment of periodontitis and its associated comorbidities.

Relieving Effect of Artemisia ordosica Krasch Extract on DSS-Induced Colitis by Regulating Immunity, Antioxidant Function, Gut Microbiota, and Bile Acid Metabolism in Mice

Artemisia ordosica Krasch, a traditional Chinese herbal medicine, possesses antibacterial, antiviral, and anti-inflammatory properties. The aim of this experiment was to investigate the therapeutic effect of Artemisia ordosica Krasch extraction (AOE) in treating colitis induced by dextran sulfate sodium (DSS) in mice. The in vitro antioxidant activity of AOE was evaluated by assessing its iron reduction capacity and scavenging capacity towards 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals (·OH). The protective effect of AOE on colitis in mice was determined by monitoring key indicators such as body weight, colon length, and survival rate in mice, as well as by assessing the expression of colon-related genes and cytokine levels. We evaluated the impact of AOE on intestinal microbiota by measuring the 16s sequencing of cecal contents and bile acid metabolism. The results showed that the iron reduction capacity of AOE was positively correlated with its concentration. The half-maximal inhibitory concentrations (IC50) for scavenging DPPH and hydroxyl radicals were 3.126 mg/mL and 6.139 mg/mL, with a 95% confidence interval of 95%. In vivo studies demonstrated that AOE reduced DSS-induced colitis in mice by increasing the colon length, enhancing antioxidant enzyme activity, inhibiting inflammatory cell infiltration, suppressing the formation of TNF-α and IL-6, and reducing malondialdehyde (MDA) levels. qPCR analysis revealed that AOE reversed the down-regulation of Claudin mRNA expression, and altered the composition of cecal microbiota, thus mitigating DSS-induced colitis. AOE plays a crucial role in alleviating colitis in mice and effectively improves DSS-induced colitis, highlighting its potential as a therapeutic agent for inflammatory bowel diseases.

Mercury reduction by agricultural organic waste-derived dissolved organic matter: Kinetic analysis and the role of light-induced free radicals.

Agricultural organic wastes can leach dissolved organic matter (DOM) into surrounding water bodies, establishing them as significant sources of aquatic DOM. Given the importance of DOM in biogeochemical cycling of mercury (Hg), this DOM may mediate divalent Hg (Hg(II)) reduction, a process that remains poorly understood. This study investigated Hg(II) reduction using DOM derived from six representative agricultural wastes, categorized into livestock manure (chicken, pig, cow) and crop straw (rice, corn, rapeseed), with systematic considerations of the kinetics of reduction processes and the involvement of key free radicals. Results revealed that photoreduction was the primary pathway for Hg(II) reduction, with pig manure DOM exhibiting the highest efficiency at 36%. Key DOM quality parameters, such as protein-like components, have been identified as critical determinants of Hg(II) photoreduction capacity. Furthermore, free radicals induced by DOM could either enhance or inhibit Hg(II) reduction capacities. Specifically, in livestock manure, the superoxide anion (O2•-)·was identified as the primary radical promoting Hg(II) photoreduction of pig manure DOM. In crop straw, hydroxyl radicals (·OH) were found to inhibit Hg(II) photoreduction, whereas O2•- promoted the Hg(II) photoreduction of rice straw DOM. These findings provide valuable insights into the role of agricultural organic wastes in biogeochemical cycling of Hg within aquatic ecosystems.

Antioxidant and antimicrobial activities of different extracts of Tragopogon dubius and Tragopogon porrifolium L. subsp. longirostris: Determination of their phytochemical contents by UHPLC-Orbitrap®-HRMS analysis

In this study, dichloromethane (DCM), n-hexane, ethanol, methanol, and natural deep eutectic solvents (NADES) were used to extract Tragopogon porrifolium L. subsp. longirostris (Sch. Bip.) Greuter and Tragopogon dubius L. Antioxidant properties (Cu2+ reduction capacity, DPPH, ABTS and Fe3+ reduction) and antimicrobial activities of these extracts were determined. Also, metabolite profiles were determined using UHPLC-Orbitrap®-HRMS. NADES extracts of both species (MIC: 0.18-0.71 mg/ml) showed significantly better antimicrobial activity against Klebsiella pneumoniae, Bacillus subtilis, and Staphylococcus aureus compared to other solvents (MIC: 25 mg/ml). The study showed that T. dubius methanol and NADES extracts had better inhibitory effects on DPPH (EC50:45.17 μg/mL, EC50:108.73 μg/mL) and ABTS (EC50:59.54 μg/mL, EC50:95.98 μg/mL) radical scavenging activities than other extracts. Similarly, T. porrifolium methanol and NADES extracts had better inhibitory effects on DPPH (EC50:48.33 μg/mL, EC50:38.72 μg/mL) and ABTS (EC50:77 μg/mL, EC50:58.93 μg/mL) radical scavenging activities than other extracts. Furthermore, Fe3+ and Cu2+ reducing capacities were highest in methanol and NADES extracts of both plants.UHPLC-Orbitrap®-HRMS was used to profile the chemical composition, validating 71 phytochemicals, with the R2 value ranging from 0.9903 to 0.9993. The method's LOD values ranged from 0.45 to 2.94, and LOQ values ranged from 1.50 to 9.78. Recovery percentages at 10, 60, and 100 ng/mL concentrations ranged from 71.73% to 116.91%, 85.36% to 115.38%, and 97.08% to 109.65%, respectively. The analysis identified 29 phytochemicals, with major compounds including chlorogenic acid, quinic acid, apigenin 7-glucuronide, vitexin, schaftoside, orientin+isoorientin, luteoloside, and isoquercitrin. The significant biological impacts of these plants as a compelling reservoir of phytochemicals with therapeutic properties.

Isolation of anti-inflammatory and cytotoxic secondary metabolites from Valeriana phu and evaluation of their mechanisms of action.

As a result of anti-inflammatory activity-guided fractionation, 16 secondary metabolites from the underground parts of Valeriana phu L. were obtained, including five new ones belonging to iridoid (1, 2, and 5), phenylpropanoid (6) and neolignan (7) chemical classes. Their structures were elucidated by 1D and 2D NMR analyses as well as HRESIMS. The in vitro anti-inflammatory activities of the extract, fractions and isolates were evaluated through NO inhibition assay on LPS-induced RAW 264.7 cells. Compounds 1-3, 7-9, 11, 13, and 16 which significantly inhibited the nitrite release (IC50 14.94-94.81μM) were also assessed for their reducing capacity on TNF-α, IL-1β, IL-6, PGE2 and COX-2 production. Compounds 3, 8, and 16 inhibited LPS induced iNOS expression levels in Western blotting. Molecular docking studies for the active compounds targeting iNOS, TNF-α and COX-2 were also carried out. Moreover, compounds with remarkable anti-inflammatory activities were tested for their potential cytotoxicity against breast (MCF-7 and MDA-MB-231), glioblastoma (U87 and A172), pancreas (MIA PaCa-2 and PANC-1), hepatocellular (Mahlavu and Hep3B) cancer cell lines by WST-8. Compounds, 7, 8, and 16 showed significant cytotoxicity against A172 and PANC-1 cell lines (IC50 18.3-21.8μM) via causing cell cycle arrest, especially in the G2/M phase and triggering the apoptotic pathway.

Synergistic activation of reburned char for ultra-low NOx emissions using flue gas recirculation and natural gas in a 10kW furnace.

The technology of powdered coal injection with recirculating flue gas and natural gas conditioning for reburning represents an advanced and innovative approach to enhancing the efficiency of coal powder reburning. By consuming excess oxygen in the recirculated flue gas, natural gas fosters an environment enriched with reducing agents, which stimulates the reactivity of reburning coal powder and augments its effectiveness in reducing nitrogen oxides (NO). This technology has been comprehensively investigated through experiments conducted in a segmented multi-reactor flow system, simulating conditions akin to those in industrial boilers. To achieve a high level of NO abatement, complete combustion of coal powder, and operational cost-effectiveness, a series of optimal operating parameters has been identified: the temperature in the reburning zone (T1) should be controlled at approximately 1573K; the reburning fuel ratio (Rf) should be maintained around 20%; the excess air coefficient (λfuel) in the reburning zone should be approximately 0.228; the residence time in the reburning zone (t2) should be 0.6s, and the burnout zone residence time (t3) should also be 0.6s; finally, the oxygen concentration in the recirculating flue gas should be regulated to around 10%. This configuration ensures that reactive intermediates such as CO∗, OH∗, H, and CHi generated through natural gas modification enhance the physicochemical structure of coal char, thus amplifying the coal char's capacity for the chemical reduction of NO. Precise control of these parameters is expected to facilitate ultra-low NO emissions, while minimizing the consumption of costly active gases and ensuring the economic efficiency of the system.

Development and performance assessment of a novel self-centering damper for slotted RC walls

Slotted RC walls exhibit better ductility compared to conventional RC walls, but inevitably lead to a reduction in lateral stiffness and load-bearing capacity. In order to improve the seismic performance and reduce the residual deformation of slotted RC walls, a novel self-centering damper (SCD) suitable for the connection of slotted RC wall is proposed. The novel SCD is composed of two diagonally intersecting disc spring devices (DSD) and multiple slit steel plate (MSSP) arranged in parallel. The construction and working principle of the novel SCD were thoroughly explained, and its theoretical model was established. Through cyclic loading tests and numerical simulations, the collaborative working mechanism of the two components was analyzed. The influence of the pre-pressed force and arrangement angle of the DSD on the energy-dissipating and self-centering capacities of the SCD was investigated. It was found that increasing the pre-pressed force and arrangement angle of the DSD would reduce residual deformation and equivalent viscous damping ratio. Then, the seismic performance of the slotted RC wall with the novel SCDs was analyzed. The results demonstrated that the slotted RC wall incorporating the SCDs exhibited superior deformation and energy-dissipating capabilities, while maintaining a relatively high level of load- bearing capacity and stiffness. Notably, the residual deformation rate of the SCDs was only 0.4 % at the design threshold, enabling disassembly and replacement after seismic events.

Upper Extremity Exercise Capacity and Muscle Oxygenation in Patients With Primary Ciliary Dyskinesia.

Patients with primary ciliary dyskinesia (PCD) have a reduction in exercise capacity from the early stages. Although there are studies investigating these patients' lower extremity exercise capacity using various methodologies, there needs to be more research on the functional exercise capacity of the upper extremities. This study aimed to compare pulmonary function, upper extremity functional exercise capacity, muscle oxygenation, muscle strength, and physical activity level in children with PCD and controls. Twenty-seven children with PCD and 26 controls were included. Pulmonary function (spirometry), upper extremity functional exercise capacity (6-min pegboard and ring test (6PBRT), muscle oxygenation (Moxy device), deltoid muscle strength (dynamometer), and physical activity level (metabolic holter) were assessed. Patients' FVC%, FEV1%, FEV1/FVC, PEF%, FEF25%-75%, deltoid muscle strength (%) were statistically decreased compared with controls (p < 0.05). The 6PBRT ring count, deltoid muscle oxygen saturations, and total hemoglobin levels were similar in both groups (p > 0.05). Pulmonary function deteriorates and upper extremity muscle strength decreases in children with PCD. The upper extremity exercise capacity of these patients remains preserved. However, upper extremity resting muscle oxygen saturation is lower in children compared to healthy children. Most patients and healthy children are inactive. The upper extremity exercise capacity possibly declines due to deteriorating pulmonary function as the patients get older, which needs to be investigated routinely. Both upper-lower extremity aerobic exercise training applied consistently and physical activity counseling as part of their pulmonary rehabilitation program should be considered in children with PCD.

Exploring Bio-remediation Strategies by a Novel Bacteria Micrococcus sp. strain HX in Cr(VI)-Contaminated Groundwater from Long-term Industrial Polluted

Hexavalent chromium (Cr(VI)) has emerged as a contaminant of heavy metal, owing to its wide use in industry. This study focuses on elucidating the interaction between microbial communities and environmental parameters in Cr(VI)-contaminated groundwater near a factory in Henan Province, and evaluating the bio-remediation potential of microorganisms toward Cr(VI) reduction. The highest concentration of Cr(VI) in the groundwater is 208.08mg/L. The dominant microbes were Proteobacteria and Bacteroidota, closely positively related to Cr(VI) and SO42-. Many of these genus have been proven to be chromium tolerant or have the ability to reduce Cr(VI). Two strains, Micrococcus sp. HX and Bacillus sp. HX-2, were isolated from contaminated groundwater, and Micrococcus sp. HX was used for the first time to reduce Cr(VI) in groundwater. The reduced ability of HX reached 90.18% at a Cr(VI) concentration of 100mg/L, while HX-2 achieved a reduction capacity of 63.8%. Micrococcus sp. HX shows the best reduction efficiency in alkaline environments (ph=8), which is close to the tannery industry wastewater. The reduction efficiency by Micrococcus sp. HX reached 67.26% in groundwater samples (Cr(VI)=26.08mg/L). Transcriptome analyses revealed oxidoreductase activity, ATP binding and the NAD(P) binding region protein-related gene expression were up-regulated. Binding reduction experiments indicated that most of the Cr(III) was detected extracellular, which suggests that the reduction of Cr(VI) by HX was mainly extracellular enzyme-catalyzed.

Effects of leading-edge serration shape on noise reduction in rod-airfoil interactions.

Leading-edge serrations inspired by owls exhibit the capability to control airfoil-turbulence interaction noise, but the design principle of the serration shape is still an open issue. To this end, we designed five types of serration shapes with different combinations of curvature, namely, triangular, ogee, anti-ogee, feather-like, and anti-feather-like. These curves are applied to serrated modifications with different bluntness levels (sharp or blunt) and amplitudes (0.05, 0.075, and 0.1 chord length). Considering these serration shapes, 30 cases with various curved types, bluntness levels, and amplitudes are investigated using compressible large-eddy simulation and the acoustic analogy of Ffowcs-Williams and Hawkings on a rod-airfoil configuration. The outcomes reveal a general trend where increased amplitude and blunted serrations are more effective in noise mitigation. Notably, the blunt feather-like (FB) serrations demonstrate the maximum noise reduction capacity across all amplitude levels, decreasing the overall sound power level by up to 2.1 dB. Through multi-process acoustic analysis, source characteristics responsible for generating noise are diagnosed. It is found that noise reduction primarily stems from the change in the source distribution and destructive interference among sound sources, consistent with prior studies. Generally, the serration shape would significantly affect the source distribution and sound interference without altering the fundamental noise reduction mechanisms. The FB shape exhibits the highest concentration of sources at its peaks and roots among all shapes. The presence of concentrated sources in these locations enhances destructive interference, effectively reducing noise emissions. The superior noise-reduction feature of FB serrations should be attributed to both the concentration of sources and the destructive interference. This extensive examination underscores the importance of serration design, especially the potential of FB serrations, in noise control strategies for rod-airfoil configurations, contributing to advancements in aeroacoustic engineering.

Effect of bonding defects on heat transfer and creep response of microprocessor-heatsink adhesive joints

Efficient thermal management in microelectronic assemblies is crucial for the optimal performance and reliability of microprocessors. This study investigates the thermal, static, and creep performance of pressure-sensitive adhesives (PSAs) used in bonding heatsinks to microchips, focusing on the impact of adhesive coverage on thermal conductivity, mechanical strength, and long-term deformation under sustained loads. Shear loading, specifically analyzed due to the prevalence of shear stresses in vertically oriented microelectronic assemblies, is critical for understanding the long-term reliability of these bonds. The thermal analysis revealed that perfectly bonded heatsinks enhanced heat dissipation, with only a minor reduction in thermal conductivity observed due to incomplete adhesive coverage. Static tests demonstrated that perfectly bonded samples exhibited better load-bearing capacity overall, although joints with defects showed higher calculated stress due to the reduced bonded area at failure, with a 21% reduction in load-bearing capacity at room temperature and a 3.5% reduction at high temperature for joints with adhesive loss. Creep tests showed that at room temperature, the time to failure decreased by approximately 150% for samples with adhesive defects, while at high temperature, the reduction was over 66%. The study found that creep life is more sensitive to defects at lower temperatures, where adhesive loss has a more pronounced impact on performance. A predictive surface model was developed to estimate time to failure based on creep stress and temperature.

Inertia Support Capability Evaluation for Wind Turbine Generators Based on Symmetrical Operation

With the increasing integration of new energy into the grid, the level of system inertia has been significantly reduced, posing a severe challenge to frequency stability. Consequently, there is an urgent need for wind turbine generators (WTGs) to actively provide inertia support through virtual inertia control. Assessing the inertia support capability of WTGs reasonably and setting appropriate controller parameters based on this assessment is a topic worthy of discussion. As WTGs’ characteristics are mostly ignored in the evaluation of inertia support capability for WTGs, an evaluation method based on symmetrical operation is proposed. The proposed method considers the impact of real inertia and aerodynamic characteristics, thereby helping to determine reasonable virtual inertia coefficients and de-loading reserve capacity for WTGs. With the proposed method, it can be determined that large WTGs can provide inertia support capabilities close to those of synchronous generators to the grid without exceeding a 0.1% reduction in reserve capacity during de-loading operation.

Genetic risk for treatment resistant schizophrenia and corresponding variation in dopamine synthesis capacity and D2/3 receptor availability in healthy individuals.

Dysfunction of dopamine systems has long been considered a hallmark of schizophrenia, and nearly all current first-line medication treatments block dopamine D2 receptors. However, approximately a quarter of patients will not adequately respond to these agents and are considered treatment-resistant. Whereas abnormally high striatal presynaptic dopamine synthesis capacity has been observed in people with schizophrenia, studies of treatment-resistant patients have not shown this pattern and have even found the opposite - i.e., reductions in striatal presynaptic dopamine synthesis capacity. Whether such reductions in fact represent clinical epiphenomena such as medication or other treatment effects or whether they rather represent neurobiological differences related to etiology has been unclear. To understand the dopaminergic implications of genetic liability for treatment-resistant schizophrenia without the confound of clinical epiphenomena, we studied a cohort of healthy individuals without neuropsychiatric illness using [18F]-FDOPA positron emission tomography (PET) and found that striatal presynaptic dopamine synthesis capacity showed an expected direct association with cumulative genetic risk burden for general schizophrenia but an inverse association with specific polygenic risk for treatment-resistant schizophrenia. Subsequent evaluation of D2/3 dopamine receptor availability in an overlapping cohort using [18F]-fallypride PET did not identify any effects of genetic risk in the striatum but found an association with treatment-resistant schizophrenia polygenic risk in the thalamus. Overall, these results align with prior PET studies in patients and implicate, at least with respect to the dopamine system, fundamentally distinct molecular mechanisms in the unique genetic liability for treatment-resistant schizophrenia.

Selective Photocatalysis of Benzyl Alcohol Valorization by Cocatalyst Engineering Over Zn2In2S5 Nanosheets

AbstractPhotocatalytic conversion of benzyl alcohol (BA) is a promising means to coproduce H2 with value‐added chemicals. However, there is a lack of an efficient strategy to regulate the selectivity of the BA conversion products. Here, by a simple cocatalyst engineering technique, the selective conversion of BA over Zn2In2S5 nanosheets (ZIS) is maneuvered. Two types of cocatalysts, i.e., Pt and Cd, are photo‐deposited onto ZIS that can shift the selectivity to diverse products, namely, Pt to benzaldehyde (BAD) and Cd to the carbon‐carbon (C─C) coupling compounds. Mechanistic studies indicate that Cd has a high reducing capacity to convert BAD back to the ketyl radical (C𝛼 radical), favoring the construction of the C─C bonds. Pt, however, facilitates the generation of C𝛼 radicals but is energetically unfavorable for their coupling reactions, resulting in the generation of BAD as the main product. Theoretical calculation reveals that the distinct catalytic behaviors of Pt and Cd stem from their different electronic structures that govern the adsorption strength to the reaction intermediates and the reaction energy barriers of the C─C coupling step. This work not only addresses the challenge of selectivity regulation for BA conversion but also brings fresh mechanistic insights into the role of the cocatalysts.

Correlations study "structure – property" of model products reaction monosaccharides non-enzymatic coloring in ethanol media

Caramel compositions based on carbohydrates are available food colorants, additionally characterized by a set of practically significant properties, in particular, antioxidant activity. In the present work, the features of the chemical structure of caramels based on the most important monosaccharides – D-glucose, D-mannose and D-galactose, and their correlations with structure-dependent parameters, such as color and reducing capacity, are studied. The syn thesis of target products was performed in water-ethanol media (90% ethanol) in the presence of alkali with thin lay er chromatography (TLC) control and subsequent dialysis. The structural features of the condensed products of the non-enzymatic coloring reaction were studied by Infrared spectroscopy (IS), which were subsequently compared with the values of the reducing capacity expressed by permanganate oxidizability and color estimated by color indices. Qualitative and quantitative analysis of the mid infrared frequency (1800–1000 cm−1) of the initial zero-order spectra and their second derivatives indicates the presence of unsaturated (enolic) fragments (1600 and 1625 cm−1) in the caramel structure. In the spectrum of the D-mannose-based composition, low-frequency shifts of the bands to 1595 and 1620 cm−1 probably indicate a higher degree of enolization. The limiting component of the structure, represent ed by bound polyglycosides, appears in systems based on D-glucose and D-galactose (strengthening of the 1150 cm−1 band). The analysis of the values of structure-dependent parameters shows a decrease in the reducing capacity and color in the series of caramels based on D- mannose &gt; D- glucose &gt; D-galactose. It correlates with the increased con tent of reducing fragments (enols) in the structure of the first system and the excessive presence of bound non-re ducing forms in the structure of the latter, as well as the previously obtained data on the kinetics of caramelization, which forms the basis of the correlation model. Comparison of the reducing capacity and the total color index CI (EBC unit) of the studied products with similar indicators of ascorbic acid and class I food caramels characterizes them with fairly close values of the same order, which suggests further research in the direction of developing and scaling the technology for producing carbohydrate caramels under the described conditions.