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Influence of fermentation on the quality of Fijian Theobroma cacao beans over two harvest seasons
(Taylor and Francis Group, 2024-10-01) Raju RN; Heyes J; Archer R; Chen Q
Theobroma cacao beans are cultivated in Fiji by smallholder farms in low volumes, mainly for export. Cocoa beans are often processed under ambient conditions by farmers and cocoa processors. Postharvest processing includes natural fermentation from six to ten days in wooden boxes, followed by sun – drying in the open for up to 14 days. The impact of fermentation conditions on key quality parameters of Fijian cocoa beans, such as temperature profile, pH, and total extractable polyphenol content (TPC) are presented in this study. The quality of fermentation was assessed using a standard method, such as a cut test followed by fermentation index (FI) measurement. A temperature increase to 40°C and variations in the pH of the bean mass were evident during natural fermentation. TPC in the cocoa beans was sensitive to temperature and pH. Fermentation was variable due to weather conditions between harvest seasons. The dry season had the best conditions for fermentation as the peak temperature of the bean mass was 40°C and the FI was high (1.39 ± 0.04) There is a need to improve fermentation during the rainy season. This can be achieved by providing training to Fijian cocoa farmers on using better fermentation techniques.
Climate-adaptive windcatcher natural ventilation integrated with passive and low-energy technologies: A review of current and future developments
(Elsevier B.V., 2025-10-01) Li J; Calautit J; Jimenez-Bescos C; Song W; Riffat S; Chen Q
The integration of natural ventilation systems, such as windcatchers, in modern buildings has garnered interest due to rising energy costs and the need for sustainable practices. Windcatchers have been adapted in many regions to enhance indoor air quality and comfort while reducing reliance on mechanical systems and air conditioners. However, extreme climates, such as hot, humid, and cold conditions, pose challenges to effective windcatcher ventilation. Consequently, passive or low-energy cooling, heating and dehumidification technologies have been developed and integrated into windcatchers to improve thermal performance. Despite extensive research, a comprehensive review synthesizing windcatcher integration with passive and low-energy technologies across diverse climates is lacking. Existing studies often focus on specific elements or singular climatic conditions, leaving a gap in understanding the holistic application and optimization of these systems in various environments. This review addresses this gap by analyzing 147 studies on windcatchers and integrating windcatchers with technologies such as evaporative cooling, earth-air heat exchangers, heat pipes, and phase change materials. It evaluates the performance of these systems in hot and arid, temperate, tropical, continental, and polar climates, offering insights into their effectiveness and challenges. Key findings indicate that windcatchers with evaporative cooling effectively reduce indoor temperatures in hot, arid climates, though water scarcity remains a limitation. Earth-air heat exchangers and passive heat recovery technologies enhance efficiency in temperate regions, while indirect evaporative cooling is promising for humidity management in tropical climates. For continental and polar climates, integrating windcatchers with stoves, heat recovery, and solar thermal technologies is proposed, as traditional designs are inadequate in extreme cold. The review offers tailored recommendations for windcatcher designs across climates, guiding future research.
Thermo-economic investigation and multi objective optimization of cascade high temperature heat pump using low global warming refrigerants
(Elsevier B.V., 2025-11-15) Hoang DK; Walmsley TG; Cleland DJ; Chen Q; Carson JK
High temperature heat pumping (HTHP) is a key technology for decarbonizing industrial process heat. This paper describes an investigation into the thermodynamic and economic performance of a cascade HTHP configured with internal heat exchangers (IHXs), using low global warming potential (GWP) refrigerants in both the top cycle and the bottom cycle. The proposed system was applied to a spray dryer case study with supply air temperature over 200 °C. A differential evolution (DE) method was used to optimize operating parameters to obtain the maximum COP. The simulation results indicated that of the cycles and refrigerants considered, the maximum COP can be obtained when using acetone or ethanol in the top cycle (TC) and butane or neopentane in the bottom cycle (BC). The use of acetone/neopentane and ethanol/neopentane achieved a highest COP of 2.42; however, better economic performance was achieved when using butane as the BC refrigerant rather than neopentane, while the economic and thermodynamic performance of the heat pumps were similar when acetone and ethanol were used as TC refrigerants. The performance of the most promising refrigerants was analyzed under off-design conditions, with minimum and maximum COP being 2.19 and 2.82, respectively obtained with the sink inlet/outlet temperature of 50 °C/230 °C and 15 °C/200 °C.
Antagonistic systemin receptors integrate the activation and attenuation of systemic wound signaling in tomato.
(Elsevier B.V., 2024-12-03) Zhou K; Wu F; Deng L; Xiao Y; Yang W; Zhao J; Wang Q; Chang Z; Zhai H; Sun C; Han H; Du M; Chen Q; Yan J; Xin P; Chu J; Han Z; Chai J; Howe GA; Li C-B; Li C
Pattern recognition receptor (PRR)-mediated perception of damage-associated molecular patterns (DAMPs) triggers the first line of inducible defenses in both plants and animals. Compared with animals, plants are sessile and regularly encounter physical damage by biotic and abiotic factors. A longstanding problem concerns how plants achieve a balance between wound defense response and normal growth, avoiding overcommitment to catastrophic defense. Here, we report that two antagonistic systemin receptors, SYR1 and SYR2, of the wound peptide hormone systemin in tomato act in a ligand-concentration-dependent manner to regulate immune homeostasis. Whereas SYR1 acts as a high-affinity receptor to initiate systemin signaling, SYR2 functions as a low-affinity receptor to attenuate systemin signaling. The expression of systemin and SYR2, but not SYR1, is upregulated upon SYR1 activation. Our findings provide a mechanistic explanation for how plants appropriately respond to tissue damage based on PRR-mediated perception of DAMP concentrations and have implications for uncoupling defense-growth trade-offs.
Mercury records from natural archives reveal ecosystem responses to changing atmospheric deposition.
(Oxford University Press, 2024-11-19) Chen Q; Wu Q; Cui Y; Wang S
Global ecosystems face mercury contamination, yet long-term data are scarce, hindering understanding of ecosystem responses to atmospheric Hg input changes. To bridge the data gap and assess ecosystem responses, we compiled and compared a mercury accumulation database from peat, lake, ice and marine deposits worldwide with atmospheric mercury deposition modelled by GEOS-Chem, focusing on trends, magnitudes, spatial-temporal distributions and impact factors. The mercury fluxes in all four deposits showed a 5- to 9-fold increase over 1700-2012, with lake and peat mercury fluxes that generally mirrored atmospheric deposition trends. Significant decreases in lake and peat mercury fluxes post-1950 in Europe evidenced effective environmental policies, whereas rises in East Asia, Africa and Oceania highlighted coal-use impacts, inter alia. Conversely, mercury fluxes in marine and high-altitude ecosystems did not align well with atmospheric deposition, emphasizing natural influences over anthropogenic impacts. Our study underscores the importance of these key regions and ecosystems for future mercury management.
Age Differences in Ileum Microbiota Density: VFAs and Their Transport-Related Gene Interactions in Tibetan Sheep
(MDPI (Basel, Switzerland), 2024-10-03) Wang F; Sha Y; He Y; Liu X; Chen X; Yang W; Chen Q; Gao M; Huang W; Wang J; Hao Z; Wang L; Yang F
Microbiota density plays an important role in maintaining host metabolism, immune function, and health, and age has a specific effect on the composition of intestinal microbiota. Therefore, the age-specific effects of age differences on the structure and function of the ileum microbiota in Tibetan sheep were investigated by determining the density of the ileum microbiota, the content of VFAs, and the expression levels of their transporter-related genes at different ages. The results showed that the contents of acetic acid and propionic acid in the ileum of Tibetan sheep in the 1.5-year-old group were significantly higher (p < 0.05) than those in other age groups, and that the contents of total VFAs were also significantly higher (p < 0.05) than those in other age groups. The relative densities of ileum Rf, Ra, and Fs were significantly higher in the 1.5-year-old group than in the other age groups (p < 0.05). The ileum epithelial VFAs transport-related genes AE2, MCT-4, and NHE1 had the highest expression in the 1.5-year-old group, and the expression of DRA was significantly lower in the 1.5-year-old group than in the 6-year-old group (p < 0.05). Correlation analysis showed that Cb, Sr, and Tb were significantly positively correlated with butyric acid concentration (p < 0.05) and negatively correlated with acetic acid, but the difference was not significant (p > 0.05); MCT-1, MCT-4, and AE2 were significantly positively correlated (p < 0.05) with acetic, propionic, and isobutyric acid concentrations; NHE1, NHE2, and MCT-4 were highly significantly positively correlated (p < 0.01) with Romboutsia and unclassified_Peptostreptococcaceae, while acetic acid was significantly positively correlated (p < 0.05) with NK4A214_group; Romboutsia, and unclassified_Peptostreptococcaceae were significantly positively correlated (p < 0.05). Therefore, compared with other ages, the 1.5-year-old Tibetan sheep had a stronger fermentation and metabolic capacity in the ileum under traditional grazing conditions on the plateau, which could provide more energy for Tibetan sheep during plateau acclimatization.
Economic burden of patients with leading cancers in China: a cost-of-illness study.
(BioMed Central Ltd, 2024-09-27) Wu Z; Yu Y; Xie F; Chen Q; Cao Z; Chen S; Liu GG
BACKGROUND: China accounts for 24% of newly diagnosed cancer cases and 30% of cancer-related deaths worldwide. Comprehensive analyses of the economic burden on patients across different cancer treatment phases, based on empirical data, are lacking. This study aims to estimate the financial burden borne by patients and analyze the cost compositions of the leading cancers with the highest number of new cases in China. METHODS: This cross-sectional cost-of-illness study analyzed patients diagnosed with lung, breast, colorectal, esophageal, liver, or gastric cancer, identified through electronic health records (EHRs) from 84 hospitals across 17 provinces in China. Patients completed any one of the initial treatment phase, follow-up phase, and relapse/metastasis phase were recruited by trained attending physicians through a stratified sampling procedure to ensure enough cases for each cancer progression stage and cancer treatment phase. Direct and indirect costs by treatment phase were collected from the EHRs and self-reported surveys. We estimated per case cost for each type of cancer, and employed subgroup analyses and multiple linear regression models to explore cost drivers. RESULTS: We recruited a total of 13,745 cancer patients across three treatment phases. The relapse/metastasis phase incurred the highest per case costs, varying from $8,890 to $14,572, while the follow-up phase was the least costly, ranging from $1,840 to $4,431. Being in the relapse/metastasis phase and having an advanced clinical stage of cancer at diagnosis were associated with significantly higher cost, while patients with low socioeconomic status borne lower costs. CONCLUSIONS: There were substantial financial burden on patients with six leading cancers in China. Health policymakers should emphasize comprehensive healthcare coverage for marginalized populations such as the uninsured, less educated, and those living in underdeveloped regions.
Reprocessable Epoxy-Anhydride Resin Enabled by a Thermally Stable Liquid Transesterification Catalyst.
(MDPI (Basel, Switzerland), 2024-11-20) Liang H; Tian W; Xu H; Ge Y; Yang Y; He E; Yang Z; Wang Y; Zhang S; Wang G; Chen Q; Wei Y; Ji Y; Jang K-S
Introducing dynamic ester bonds into epoxy-anhydride resins enhances the reprocessability of the crosslinked network, facilitated by various types of transesterification catalysts. However, existing catalysts, such as metal salts and organic molecules, often struggle with dispersion, volatility, or structural instability issues. Here, we propose to solve such problems by incorporating a liquid-state, thermally stable transesterification catalyst into epoxy resins. This catalyst, an imidazole derivative, can be uniformly dispersed in the epoxy resin at room temperature. In addition, it shows high-temperature structural stability above at least 200 °C as the synergistic effects of the electron-withdrawing group and steric bulk can be leveraged. It can also effectively promote transesterification at elevated temperatures, allowing for the effective release of shear stress. This property enables the thermal recycling and reshaping of the fully crosslinked epoxy-anhydride resin. This strategy not only enhances the functionality of epoxy resins but also broadens their applicability across various thermal and mechanical environments.
Assessment of clinical feasibility:offline adaptive radiotherapy for lung cancer utilizing kV iCBCT and UNet++ based deep learning model.
(Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine, 2024-11-29) Zeng H; Chen Q; E X; Feng Y; Lv M; Zeng S; Shen W; Guan W; Zhang Y; Zhao R; Wang S; Yu J
Background Lung cancer poses a significant global health challenge. Adaptive radiotherapy (ART) addresses uncertainties due to lung tumor dynamics. We aimed to investigate a comprehensively and systematically validated offline ART regimen with high clinical feasibility for lung cancer. Methods This study enrolled 102 lung cancer patients, who underwent kV iterative cone-beam computed tomography (iCBCT). Data collection included iCBCT and planning CT (pCT) scans. Among these, data from 70 patients were employed for training the UNet++ based deep learning model, while 15 patients were allocated for testing the model. The model transformed iCBCT into adaptive CT (aCT). Clinical radiotherapy feasibility was verified in 17 patients. The dosimetric evaluation encompassed GTV, organs at risk (OARs), and monitor units (MU), while delivery accuracy was validated using ArcCHECK and thermoluminescent dosimeter (TLD) detectors. Results The UNet++ based deep learning model substantially improved image quality, reducing mean absolute error (MAE) by 70.05%, increasing peak signal-to-noise ratio (PSNR) by 17.97%, structural similarity (SSIM) by 7.41%, and the Hounsfield Units (HU) of aCT approaching a closer proximity to pCT compared to kV iCBCT. There were no significant differences observed in the dosimetric parameters of GTV and OARs between the aCT and pCT plans, confirming the accuracy of the dose maps in ART plans. Similarly, MU manifested no notable disparities, underscoring the consistency in treatment efficiency. Gamma passing rates for intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans derived from aCT and pCT exceeded 98%, while the deviations in TLD measurements (within 2% to 7%) also exhibited no significant differences, thus corroborating the precision of dose delivery. Conclusion An offline ART regimen utilizing kV iCBCT and UNet++ based deep learning model is clinically feasible for lung cancer treatment. This approach provides enhanced image quality, comparable treatment plans to pCT, and precise dose delivery.
Study of the Interactions between Muscle Fatty Acid Composition, Meat Quality-Related Genes and the Ileum Microbiota in Tibetan Sheep at Different Ages.
(MDPI (Basel, Switzerland), 2024-02-23) Wang F; Sha Y; Liu X; He Y; Hu J; Wang J; Li S; Shao P; Chen X; Yang W; Chen Q; Gao M; Huang W; Panea B
The intestinal microbiota of ruminants is an important factor affecting animal production and health. Research on the association mechanism between the intestinal microbiota and meat quality of ruminants will play a positive role in understanding the formation mechanism of meat quality in ruminants and improving production efficiency. In this study, the fatty acid composition and content, expression of related genes, and structural characteristics of the ileum microbiota of ewes of Tibetan sheep at different ages (4 months, 1.5 years, 3.5 years, and 6 years) were detected and analyzed. The results revealed significant differences in fatty acid composition and content in the muscle of Tibetan sheep at different ages (p < 0.05); in addition, the content of MUFAs in the longissimus dorsi muscle and leg muscle was higher. Similarly, the expressions of muscle-related genes differed among the different age groups, and the expression of the LPL, SCD, and FABP4 genes was higher in the 1.5-year-old group. The ileum microbiota diversity was higher in the 1.5-year-old group, the Romboutsia abundance ratio was significantly higher in the 1.5-year-old group (p < 0.05), and there was a significant positive correlation with oleic acid (C18:1n9c) (p < 0.05). In conclusion, the content of beneficial fatty acids in the longissimus dorsi muscle and leg muscle of Tibetan sheep was higher at 1.5 years of age, and the best slaughter age was 1.5 years. This study provides a reference for in-depth research on the mechanism of the influence of the gut microbiota on meat quality and related regulation.

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