Journal Articles
Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915
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Item 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 JKHigh 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.Item 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 CPattern 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.Item 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 SGlobal 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.Item 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 FMicrobiota 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.Item 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 GGBACKGROUND: 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.Item 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-SIntroducing 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.Item 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 JBackground 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.Item 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 BThe 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.Item An accumulated mutation gained in mosquito cells enhances Zika virus virulence and fitness in mice.(American Society for Microbiology, 2024-10-16) Fan X-X; Li R-T; Zhu Y-B; Chen Q; Li X-F; Cao T-S; Zhao H; Cheng G; Qin C-F; Heise MTZika virus (ZIKV) remains a significant public health threat worldwide. A number of adaptive mutations have accumulated within the genome of ZIKV during global transmission, some of which have been linked to specific phenotypes. ZIKV maintains an alternating cycle of replication between mosquitoes and vertebrate hosts, but the role of mosquito-specific adaptive mutations in ZIKV has not been well investigated. In this study, we demonstrated that serial passaging of ZIKV in mosquito Aag2 cells led to the emergence of critical amino acid substitutions, including A94V in the prM protein and V153D and H401Y in the E protein. Further characterization via reverse genetics revealed that the H401Y substitution in the E protein did not augment viral replication in mosquitoes but significantly enhanced neurovirulence and lethality compared with those of the wild-type (WT) virus in mice. More importantly, the H401Y mutant maintained its virulence phenotype in mice after propagation in mosquitoes in mosquito-mouse cycle model. In particular, recombinant ZIKV harboring the H401Y substitution showed enhanced competitive fitness over WT ZIKV in various mammalian cells and mouse brains, but not in mosquito cells. Notably, the H401Y substitution in the ZIKV E protein has been detected in recent isolates derived from both mosquitoes and humans in Asia and the Americas. In summary, our findings not only identify a novel virulence determinant of ZIKV but also highlight the complexity of the relationship between the evolution of vector-borne viruses and their clinical outcome in nature.Item Nphos: Database and Predictor of Protein N-phosphorylation.(Oxford University Press, 2024-04-10) Zhao M-X; Ding R-F; Chen Q; Meng J; Li F; Fu S; Huang B; Liu Y; Ji Z-L; Zhao Y; Xue YProtein N-phosphorylation is widely present in nature and participates in various biological processes. However, current knowledge on N-phosphorylation is extremely limited compared to that on O-phosphorylation. In this study, we collected 11,710 experimentally verified N-phosphosites of 7344 proteins from 39 species and subsequently constructed the database Nphos to share up-to-date information on protein N-phosphorylation. Upon these substantial data, we characterized the sequential and structural features of protein N-phosphorylation. Moreover, after comparing hundreds of learning models, we chose and optimized gradient boosting decision tree (GBDT) models to predict three types of human N-phosphorylation, achieving mean area under the receiver operating characteristic curve (AUC) values of 90.56%, 91.24%, and 92.01% for pHis, pLys, and pArg, respectively. Meanwhile, we discovered 488,825 distinct N-phosphosites in the human proteome. The models were also deployed in Nphos for interactive N-phosphosite prediction. In summary, this work provides new insights and points for both flexible and focused investigations of N-phosphorylation. It will also facilitate a deeper and more systematic understanding of protein N-phosphorylation modification by providing a data and technical foundation. Nphos is freely available at http://www.bio-add.org/Nphos/ and http://ppodd.org.cn/Nphos/.