1. |
- Middha, Pooja K., et al.
(author)
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A genome-wide gene-environment interaction study of breast cancer risk for women of European ancestry
- 2023
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In: Breast Cancer Research. - : BioMed Central (BMC). - 1465-5411 .- 1465-542X. ; 25:1
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Journal article (peer-reviewed)abstract
- Background Genome-wide studies of gene-environment interactions (GxE) may identify variants associated with disease risk in conjunction with lifestyle/environmental exposures. We conducted a genome-wide GxE analysis of similar to 7.6 million common variants and seven lifestyle/environmental risk factors for breast cancer risk overall and for estrogen receptor positive (ER +) breast cancer. Methods Analyses were conducted using 72,285 breast cancer cases and 80,354 controls of European ancestry from the Breast Cancer Association Consortium. Gene-environment interactions were evaluated using standard unconditional logistic regression models and likelihood ratio tests for breast cancer risk overall and for ER + breast cancer. Bayesian False Discovery Probability was employed to assess the noteworthiness of each SNP-risk factor pairs. Results Assuming a 1 x 10(-5) prior probability of a true association for each SNP-risk factor pairs and a Bayesian False Discovery Probability < 15%, we identified two independent SNP-risk factor pairs: rs80018847(9p13)-LINGO2 and adult height in association with overall breast cancer risk (ORint = 0.94, 95% CI 0.92-0.96), and rs4770552(13q12)-SPATA13 and age at menarche for ER + breast cancer risk (ORint = 0.91, 95% CI 0.88-0.94). Conclusions Overall, the contribution of GxE interactions to the heritability of breast cancer is very small. At the population level, multiplicative GxE interactions do not make an important contribution to risk prediction in breast cancer.
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2. |
- Song, Guohe, et al.
(author)
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TIMP1 is a prognostic marker for the progression and metastasis of colon cancer through FAK-PI3K/AKT and MAPK pathway
- 2016
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In: Journal of Experimental & Clinical Cancer Research. - London, United Kingdom : BioMed Central (BMC). - 1756-9966. ; 35:1
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Journal article (peer-reviewed)abstract
- Background: Tissue inhibitor matrix metalloproteinase 1 (TIMP1) plays a vital role in carcinogenesis, yet its precise functional roles and regulation remain unclear. In this study, we aim to investigate its biological function and clinical significance in human colon cancer.Methods: We analyzed the expression of TIMP1 in both public database (Oncomine and TCGA) and 94 cases of primary colon cancer and matched normal colon tissue specimens. The underlying mechanisms of altered TIMP1 expression on cell tumorigenesis, proliferation, and metastasis were explored in vitro and in vivo.Results: TIMP1 was overexpressed in colon tumorous tissues and lymph node metastasis specimens than in normal tissues. The aberrant expression of TIMP1 was significantly associated with the regional lymph node metastasis (p = 0.033), distant metastasis (p = 0.039), vascular invasion (p = 0.024) and the American Joint Committee on Cancer (AJCC) stage (p = 0.026). Cox proportional hazards model showed that TIMP1 was an independent prognostic indicator of disease-free survival (HR = 2.603, 95 % CI: 1.115-6.077, p = 0.027) and overall survival (HR = 2.907, 95 % CI: 1.254-6.737, p = 0.013) for patients with colon cancer. Consistent with this, our findings highlight that suppression of TIMP1 expression decreased proliferation, and metastasis but increased apoptosis by inducing TIMP1 specific regulated FAK-PI3K/AKT and MAPK pathway.Conclusion: TIMP1 might play an important role in promoting tumorigenesis and metastasis of human colon cancer and function as a potential prognostic indicator for colon cancer.
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3. |
- Kapoor, Pooja Middha, et al.
(author)
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Assessment of interactions between 205 breast cancer susceptibility loci and 13 established risk factors in relation to breast cancer risk, in the Breast Cancer Association Consortium
- 2020
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In: International Journal of Epidemiology. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 49:1, s. 216-232
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Journal article (peer-reviewed)abstract
- Background: Previous gene-environment interaction studies of breast cancer risk have provided sparse evidence of interactions. Using the largest available dataset to date, we performed a comprehensive assessment of potential effect modification of 205 common susceptibility variants by 13 established breast cancer risk factors, including replication of previously reported interactions. Methods: Analyses were performed using 28 176 cases and 32 209 controls genotyped with iCOGS array and 44 109 cases and 48 145 controls genotyped using OncoArray from the Breast Cancer Association Consortium (BCAC). Gene-environment interactions were assessed using unconditional logistic regression and likelihood ratio tests for breast cancer risk overall and by estrogen-receptor (ER) status. Bayesian false discovery probability was used to assess the noteworthiness of the meta-analysed array-specific interactions. Results: Noteworthy evidence of interaction at ≤1% prior probability was observed for three single nucleotide polymorphism (SNP)-risk factor pairs. SNP rs4442975 was associated with a greater reduction of risk of ER-positive breast cancer [odds ratio (OR)int = 0.85 (0.78-0.93), Pint = 2.8 x 10-4] and overall breast cancer [ORint = 0.85 (0.78-0.92), Pint = 7.4 x 10-5) in current users of estrogen-progesterone therapy compared with non-users. This finding was supported by replication using OncoArray data of the previously reported interaction between rs13387042 (r2 = 0.93 with rs4442975) and current estrogen-progesterone therapy for overall disease (Pint = 0.004). The two other interactions suggested stronger associations between SNP rs6596100 and ER-negative breast cancer with increasing parity and younger age at first birth. Conclusions: Overall, our study does not suggest strong effect modification of common breast cancer susceptibility variants by established risk factors.
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4. |
- Kapoor, Pooja Middha, et al.
(author)
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Combined associations of a polygenic risk score and classical risk factors with breast cancer risk
- 2021
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In: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 113:3, s. 329-337
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Journal article (peer-reviewed)abstract
- We evaluated the joint associations between a new 313-variant PRS (PRS313) and questionnaire-based breast cancer risk factors for women of European ancestry, using 72 284 cases and 80 354 controls from the Breast Cancer Association Consortium. Interactions were evaluated using standard logistic regression and a newly developed case-only method for breast cancer risk overall and by estrogen receptor status. After accounting for multiple testing, we did not find evidence that per-standard deviation PRS313 odds ratio differed across strata defined by individual risk factors. Goodness-of-fit tests did not reject the assumption of a multiplicative model between PRS313 and each risk factor. Variation in projected absolute lifetime risk of breast cancer associated with classical risk factors was greater for women with higher genetic risk (PRS313 and family history) and, on average, 17.5% higher in the highest vs lowest deciles of genetic risk. These findings have implications for risk prevention for women at increased risk of breast cancer.
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5. |
- Wang, Xiaoliang, et al.
(author)
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Genome-wide interaction analysis of menopausal hormone therapy use and breast cancer risk among 62,370 women
- 2022
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In: Scientific Reports. - : Springer Nature. - 2045-2322. ; 12:1
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Journal article (peer-reviewed)abstract
- Use of menopausal hormone therapy (MHT) is associated with increased risk for breast cancer. However, the relevant mechanisms and its interaction with genetic variants are not fully understood. We conducted a genome-wide interaction analysis between MHT use and genetic variants for breast cancer risk in 27,585 cases and 34,785 controls from 26 observational studies. All women were post-menopausal and of European ancestry. Multivariable logistic regression models were used to test for multiplicative interactions between genetic variants and current MHT use. We considered interaction p-values < 5 x 10(-8) as genome-wide significant, and p-values < 1 x 10(-5) as suggestive. Linkage disequilibrium (LD)-based clumping was performed to identify independent candidate variants. None of the 9.7 million genetic variants tested for interactions with MHT use reached genome-wide significance. Only 213 variants, representing 18 independent loci, had p-values < 1 x 10(5). The strongest evidence was found for rs4674019 (p-value = 2.27 x 10(-7)), which showed genome-wide significant interaction (p-value = 3.8 x 10(-8)) with current MHT use when analysis was restricted to population-based studies only. Limiting the analyses to combined estrogen-progesterone MHT use only or to estrogen receptor (ER) positive cases did not identify any genome-wide significant evidence of interactions. In this large genome-wide SNP-MHT interaction study of breast cancer, we found no strong support for common genetic variants modifying the effect of MHT on breast cancer risk. These results suggest that common genetic variation has limited impact on the observed MHT-breast cancer risk association.
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6. |
- Xiao, Chao, et al.
(author)
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RBBP6 increases radioresistance and serves as a therapeutic target for preoperative radiotherapy in colorectal cancer
- 2018
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In: Cancer Science. - : Blackwell Publishing. - 1347-9032 .- 1349-7006. ; 109:4, s. 1075-1087
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Journal article (peer-reviewed)abstract
- Radiotherapy (RT) can be used as preoperative treatment to downstage initially unresectable locally rectal carcinoma, but the radioresistance and recurrence remain significant problems. Retinoblastoma binding protein 6 (RBBP6) has been implicated in the regulation of cell cycle, apoptosis and chemoresistance both in vitro and in vivo. This study investigated whether the inhibition of RBBP6 expression would improve radiosensitivity in human colorectal cancer cells. After SW620 and HT29 cells were exposed to radiation, the levels of RBBP6 mRNA and protein increased over time in both two cells. Moreover, a significant reduction in clonogenic survival and a decrease in cell viability in parallel with an obvious increase in cell apoptosis were demonstrated in irradiated RBBP6-knockdown cells. Besides, transfection with RBBP6 shRNA improved levels of G2-M phase arrest which blocked the cells in a more radiosensitive period of the cell cycle. These observations indicated that cell cycle and apoptosis mechanisms may be connected with tumor cell survival following radiotherapy. In vivo, tumor growth rate of nude mice in RBBP6-knockdown group was significantly slower than that in other groups. These results indicated that RBBP6 overexpression could resist colorectal cancer cells against radiation by regulating cell cycle and apoptosis pathways, and inhibition of RBBP6 could enhance radiosensitivity of human colorectal cancer.
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7. |
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8. |
- Harner, Tom, et al.
(author)
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Air synthesis review : polycyclic aromatic compounds in the oil sands region
- 2018
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In: Environmental Reviews. - : Canadian Science Publishing. - 1181-8700 .- 1208-6053. ; 26:4, s. 430-468
-
Research review (peer-reviewed)abstract
- This air synthesis review presents the current state of knowledge on the sources, fates, and effects for polycyclic aromatic compounds (PACs) and related chemicals released to air in the oil sands region (OSR) in Alberta, Canada. Through the implementation of the Joint Canada-Alberta Oil Sands Monitoring Program in 2012 a vast amount of new information on PACs has been acquired through directed monitoring and research projects and reported to the scientific community and public. This new knowledge addresses questions related to cumulative effects and informs the sustainable management of the oil sands resource while helping to identify gaps in understanding and priorities for future work. As a result of this air synthesis review on PACs, the following topics have been identified as new science priorities: (i) improving emissions reporting to better account for fugitive mining emissions of PACs that includes a broader range of PACs beyond the conventional polycyclic aromatic hydrocarbons (PAHs) including, inter alia, alkylated-PAHs (alk-PAHs), dibenzothiophene (DBT), alk-DBTs, nitro-PAHs, oxy-PAHs including quinones and thia-and aza-arenes; (ii) improving information on the ambient concentrations, long-range transport, and atmospheric deposition of these broader classes of PACs and their release (with co-contaminants) from different types of mining activities; (iii) further optimizing electricity-free and cost-effective approaches for assessing PAC deposition (e.g., snow sampling, lichens, passive ambient sampling) spatially across the OSR and downwind regions; (iv) designing projects that integrate monitoring efforts with source attribution models and ecosystem health studies to improve understanding of sources, receptors, and effects; (v) further optimizing natural deposition archives (e.g., sediment, peat, tree rings) and advanced forensic techniques (e.g., isotope analysis, marker compounds) to provide better understanding of sources of PACs in the OSR over space and time; (vi) conducting process research to improve model capabilities for simulating atmospheric chemistry of PACs and assessing exposure to wildlife and humans; and (vii) developing tools and integrated strategies for assessing cumulative risk to wildlife and humans by accounting for the toxicity of the mixture of chemicals in air rather than on a single compound basis.
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9. |
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10. |
- Hidaka, Akihisa, et al.
(author)
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Intake of Dietary Fruit, Vegetables, and Fiber and Risk of Colorectal Cancer According to Molecular Subtypes : A Pooled Analysis of 9 Studies
- 2020
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In: Cancer Research. - 0008-5472 .- 1538-7445. ; 80:20, s. 4578-4590
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Journal article (peer-reviewed)abstract
- Protective associations of fruits, vegetables, and fiber intake with colorectal cancer risk have been shown in many, but not all epidemiologic studies. One possible reason for study heterogeneity is that dietary factors may have distinct effects by colorectal cancer molecular subtypes. Here, we investigate the association of fruit, vegetables, and fiber intake with four well-established colorectal cancer molecular subtypes separately and in combination. Nine observational studies including 9,592 cases with molecular subtypes for microsatellite instability (MSI), CpG island methylator phenotype (CIMP), and somatic mutations in BRAF and KRAS genes, and 7,869 controls were analyzed. Both case-only logistic regression analyses and polytomous logistic regression analyses (with one control set and multiple case groups) were used. Higher fruit intake was associated with a trend toward decreased risk of BRAF-mutated tumors [OR 4th vs. 1st quartile = 0.82 (95% confidence interval, 0.65–1.04)] but not BRAF-wildtype tumors [1.09 (0.97–1.22); P difference as shown in case-only analysis = 0.02]. This difference was observed in case–control studies and not in cohort studies. Compared with controls, higher fiber intake showed negative association with colorectal cancer risk for cases with microsatellite stable/MSI-low, CIMP-negative, BRAF-wildtype, and KRAS-wildtype tumors (Ptrend range from 0.03 to 3.4e-03), which is consistent with the traditional adenoma-colorectal cancer pathway. These negative associations were stronger compared with MSI-high, CIMP-positive, BRAF-mutated, or KRAS-mutated tumors, but the differences were not statistically significant. These inverse associations for fruit and fiber intake may explain, in part, inconsistent findings between fruit or fiber intake and colorectal cancer risk that have previously been reported.
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11. |
- Huang, Zhifeng, et al.
(author)
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Three-dimensional posture optimization for biped robot stepping over large ditch based on a ducted-fan propulsion system
- 2020
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In: IEEE International Conference on Intelligent Robots and Systems. - 2153-0858 .- 2153-0866. ; , s. 3591-3597
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Conference paper (peer-reviewed)abstract
- The recent progress of an ongoing project utilizing a ducted-fan propulsion system to improve a humanoid robot's ability to step over large ditches is reported. A novel method (GAS) based on the genetic algorithm with smoothness constraint can effectively minimize the thrust by optimizing the robot's posture during 3D stepping. The significant advantage of the method is that it can realize the continuity and smoothness of the thrust and pelvis trajectories. The method enables the landing point of the robot's swing foot to be not only in the forward but also in a side direction. The methods were evaluated by simulation and by being applied on a prototype robot, JetHR1. By keeping a quasistatic balance, the robot could step over a ditch with a span of 450 mm (as much as 97% of the length of the robot's leg) in 3D stepping.
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12. |
- Jarvik, Gail P., et al.
(author)
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Hemochromatosis risk genotype is not associated with colorectal cancer or age at its diagnosis
- 2020
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In: Human Genetics and Genomics Advances. - : Cell press. - 2666-2477. ; 1:1
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Journal article (peer-reviewed)abstract
- Homozygotes for the higher penetrance hemochromatosis risk allele, HFE c.845G>A (p.Cys282Tyr, or C282Y), have been reported to be at a 2- to 3-fold increased risk for colorectal cancer (CRC). These results have been reported for small sample size studies with no information about age at diagnosis for CRC. An association with age at diagnosis might alter CRC screening recommendations. We analyzed two large European ancestry datasets to assess the association of HFE genotype with CRC risk and age at CRC diagnosis. The first dataset included 59,733 CRC or advanced adenoma cases and 72,351 controls from a CRC epidemiological study consortium. The second dataset included 13,564 self-reported CRC cases and 2,880,218 controls from the personal genetics company, 23andMe. No association of the common hereditary hemochromatosis (HH) risk genotype and CRC was found in either dataset. The odds ratios (ORs) for the association of CRC and HFE C282Y homozygosity were 1.08 (95% confidence interval [CI], 0.91–1.29; p = 0.4) and 1.01 (95% CI, 0.78–1.31, p = 0.9) in the two cohorts, respectively. Age at CRC diagnosis also did not differ by HFE C282Y/C282Y genotype in either dataset. These results indicate no increased CRC risk in individuals with HH genotypes and suggest that persons with HH risk genotypes can follow population screening recommendations for CRC.
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13. |
- Jin, J., et al.
(author)
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A GAN-Based Short-Term Link Traffic Prediction Approach for Urban Road Networks Under a Parallel Learning Framework
- 2022
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In: IEEE transactions on intelligent transportation systems (Print). - : Institute of Electrical and Electronics Engineers (IEEE). - 1524-9050 .- 1558-0016. ; 23:9, s. 16185-16196
-
Journal article (peer-reviewed)abstract
- Road link speed is often employed as an essential measure of traffic state in the operation of an urban traffic network. Not only real-time traffic demand but also signal timings and other local planning factors are major influential factors. This paper proposes a short-term traffic speed prediction approach, called PL-WGAN, for urban road networks, which is considered an important part of a novel parallel learning framework for traffic control and operation. The proposed method applies Wasserstein Generative Adversarial Nets (WGAN) for robust data-driven traffic modeling using a combination of generative neural network and discriminative neural network. The generative neural network models the road link features of the adjacent intersections and the control parameters of intersections using a hybrid graph block. In addition, the spatial-temporal relations are captured by stacking a graph convolutional network (GCN), a recurrent neural network (RNN), and an attention mechanism. A comprehensive computational experiment was carried out including comparing model prediction and computational performances with several state-of-the-art deep learning models. The proposed approach has been implemented and applied for predicting short-term link traffic speed in a large-scale urban road network in Hangzhou, China. The results suggest that it provides a scalable and effective traffic prediction solution for urban road networks.
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14. |
- Jin, Junchen, et al.
(author)
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PRECOM : A Parallel Recommendation Engine for Control, Operations, and Management on Congested Urban Traffic Networks
- 2021
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In: IEEE transactions on intelligent transportation systems (Print). - : Institute of Electrical and Electronics Engineers (IEEE). - 1524-9050 .- 1558-0016. ; , s. 1-11
-
Journal article (peer-reviewed)abstract
- This paper proposes a parallel recommendation engine, PRECOM, for traffic control operations to mitigate congestion of road traffic in the metropolitan area. The recommendation engine can provide, in real-time, effective and optimal control plans to traffic engineers, who are responsible for manually calibrating traffic signal plans especially when a road network suffers from heavy congestion due to disruptive events. With the idea of incorporating expert knowledge in the operation loop, the PRECOM system is designed to include three conceptual components: an artificial system model, a computational experiment module, and a parallel execution module. Meanwhile, three essential algorithmic steps are implemented in the recommendation engine: a candidate generator based on a graph model, a spatiotemporal ranker, and a context-aware re-ranker. The PRECOM system has been deployed in the city of Hangzhou, China, through both offline and online evaluation. The experimental results are promising, and prove that the recommendation system can provide effective support to the current human-in-the-loop control scheme in the practice of traffic control, operations, and management.
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15. |
- King, Sontoria D., et al.
(author)
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Genetic Susceptibility to Nonalcoholic Fatty Liver Disease and Risk for Pancreatic Cancer: Mendelian Randomization
- 2023
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In: Cancer Epidemiology, Biomarkers and Prevention. - : American Association For Cancer Research (AACR). - 1055-9965 .- 1538-7755. ; 32:9, s. 1265-1269
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Journal article (peer-reviewed)abstract
- BACKGROUND: There are conflicting data on whether nonalcoholic fatty liver disease (NAFLD) is associated with susceptibility to pancreatic cancer. Using Mendelian randomization (MR), we investigated the relationship between genetic predisposition to NAFLD and risk for pancreatic cancer.METHODS: Data from genome-wide association studies (GWAS) within the Pancreatic Cancer Cohort Consortium (PanScan; cases n = 5,090, controls n = 8,733) and the Pancreatic Cancer Case Control Consortium (PanC4; cases n = 4,163, controls n = 3,792) were analyzed. We used data on 68 genetic variants with four different MR methods [inverse variance weighting (IVW), MR-Egger, simple median, and penalized weighted median] separately to predict genetic heritability of NAFLD. We then assessed the relationship between each of the four MR methods and pancreatic cancer risk, using logistic regression to calculate ORs and 95% confidence intervals (CI), adjusting for PC risk factors, including obesity and diabetes.RESULTS: No association was found between genetically predicted NAFLD and pancreatic cancer risk in the PanScan or PanC4 samples [e.g., PanScan, IVW OR, 1.04; 95% confidence interval (CI), 0.88-1.22; MR-Egger OR, 0.89; 95% CI, 0.65-1.21; PanC4, IVW OR, 1.07; 95% CI, 0.90-1.27; MR-Egger OR, 0.93; 95% CI, 0.67-1.28]. None of the four MR methods indicated an association between genetically predicted NAFLD and pancreatic cancer risk in either sample.CONCLUSIONS: Genetic predisposition to NAFLD is not associated with pancreatic cancer risk.IMPACT: Given the close relationship between NAFLD and metabolic conditions, it is plausible that any association between NAFLD and pancreatic cancer might reflect host metabolic perturbations (e.g., obesity, diabetes, or metabolic syndrome) and does not necessarily reflect a causal relationship between NAFLD and pancreatic cancer.
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16. |
- Marcotte, Harold, et al.
(author)
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Conversion of monoclonal IgG to dimeric and secretory IgA restores neutralizing ability and prevents Infection of Omicron lineages
- 2024
-
In: Proceedings of the National Academy of Sciences of the United States of America. - : NATL ACAD SCIENCES. - 0027-8424 .- 1091-6490. ; 121:3
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Journal article (peer-reviewed)abstract
- The emergence of Omicron lineages and descendent subvariants continues to present a severe threat to the effectiveness of vaccines and therapeutic antibodies. We have previ- ously suggested that an insufficient mucosal immunoglobulin A (IgA) response induced by the mRNA vaccines is associated with a surge in breakthrough infections. Here, we further show that the intramuscular mRNA and/or inactivated vaccines cannot suffi- ciently boost the mucosal secretory IgA response in uninfected individuals, particu- larly against the Omicron variant. We thus engineered and characterized recombinant monomeric, dimeric, and secretory IgAl antibodies derived from four neutralizing IgG monoclonal antibodies (mAbs 01A05, rmAb23, DXP-604, and XG014) targeting the receptor-binding domain of the spike protein. Compared to their parental IgG antibod- ies, dimeric and secretory IgAl antibodies showed a higher neutralizing activity against different variants of concern (VOCs), in part due to an increased avidity. Importantly, the dimeric or secretory IgAl form of the DXP-604 antibody significantly outperformed its parental IgG antibody, and neutralized the Omicron lineages BA.1, BA.2, and BA.4/5 with a 25- to 75-fold increase in potency. In human angiotensin converting enzyme 2 (ACE2) transgenic mice, a single intranasal dose of the dimeric IgA DXP-604 conferred prophylactic and therapeutic protection against Omicron BA.5. Thus, dimeric or secre- tory IgA delivered by nasal administration may potentially be exploited for the treatment Iand prevention of Omicron infection, thereby providing an alternative tool for combating immune evasion by the current circulating subvariants and, potentially, future VOCs.
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17. |
- Wang, Hao Luo, et al.
(author)
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A Data-driven Survival Modelling Approach for Predictive Maintenance of Battery Electric Trucks
- 2023
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Conference paper (peer-reviewed)abstract
- Predictive Maintenance (PdM) aims to estimate the optimal moment when the maintenance of an industrial asset should be performed according to its actual health status. The goal is to minimize the costs, by finding the optimal point where the sum of the prevention and repair cost is at the lowest. Data-driven model may predict whether an asset is close to a real breakdown, therefore helping to build more cost-efficient maintenance strategies. This paper focuses on survival analysis based predictive maintenance applied to the operation of Battery Electric Trucks (BET). Cox Proportional Hazards and Random Survival Forests methods are adopted for modelling time-to-failure and the associated survival functions. Detailed telematics data from BET vehicles in real operations are used for modelling and analysis. The model performance is further improved by the feature selection and hyperparameter tuning processes.
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18. |
- Wang, Juncheng, et al.
(author)
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Preparation and in vitro evaluation of strontium-doped calcium silicate/gypsum bioactive bone cement
- 2014
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In: Biomedical Materials. - : IOP Publishing. - 1748-6041 .- 1748-605X. ; 9:4, s. 045002-
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Journal article (peer-reviewed)abstract
- The combination of two or more bioactive components with different biodegradability could cooperatively improve the physicochemical and biological performances of the biomaterials. Here we explore the use of alpha-calcium sulfate hemihydrate (alpha-CSH) and calcium silicate with and without strontium doping (Sr-CSi, CSi) to fabricate new bioactive cements with appropriate biodegradability as bone implants. The cements were fabricated by adding different amounts (0-35 wt%) of Sr-CSi (or CSi) into the alpha-CSH-based pastes at a liquid-to-solid ratio of 0.4. The addition of Sr-CSi into alpha-CSH cements not only led to a pH rise in the immersion medium, but also changed the surface reactivity of cements, making them more bioactive and therefore promoting apatite mineralization in simulated body fluid (SBF). The impact of additives on long-term in vitro degradation was evaluated by soaking the cements in Tris buffer, SBF, and alpha-minimal essential medium (alpha-MEM) for a period of five weeks. An addition of 20% Sr-CSi to alpha-CSH cement retarded the weight loss of the samples to 36% (in Tris buffer), 43% (in SBF) and 54% (in alpha-MEM) as compared with the pure alpha-CSH cement. However, the addition of CSi resulted in a slightly faster degradation in comparison with Sr-CSi in these media. Finally, the in vitro cell-ion dissolution products interaction study using human fetal osteoblast cells demonstrated that the addition of Sr-CSi improved cell viability and proliferation. These results indicate that tailorable bioactivity and biodegradation behavior can be achieved in gypsum cement by adding Sr-CSi, and such biocements will be of benefit for enhancing bone defect repair.
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19. |
- Wang, Xiaoliang, et al.
(author)
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Association between Smoking and Molecular Subtypes of Colorectal Cancer
- 2021
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In: JNCI Cancer Spectrum. - : Oxford University Press. - 2515-5091. ; 5:4
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Journal article (peer-reviewed)abstract
- Background: Smoking is associated with colorectal cancer (CRC) risk. Previous studies suggested this association may be restricted to certain molecular subtypes of CRC, but large-scale comprehensive analysis is lacking.Methods: A total of 9789 CRC cases and 11 231 controls of European ancestry from 11 observational studies were included. We harmonized smoking variables across studies and derived sex study specific quartiles of pack-years of smoking for analysis. Four somatic colorectal tumor markers were assessed individually and in combination, including BRAF mutation, KRAS mutation, CpG island methylator phenotype (CIMP), and microsatellite instability (MSI) status. A multinomial logistic regression analysis was used to assess the association between smoking and risk of CRC subtypes by molecular characteristics, adjusting for age, sex, and study. All statistical tests were 2-sided and adjusted for Bonferroni correction.Results: Heavier smoking was associated with higher risk of CRC overall and stratified by individual markers (P < .trend <01). The associations differed statistically significantly between all molecular subtypes, which was the most statistically significant for CIMP and BRAF. Compared with never-smokers, smokers in the fourth quartile of pack-years had a 90% higher risk of CIMP-positive CRC (odds ratio 1.90, 95% confidence interval 1.60 to 2.26) but only 35% higher risk for CIMP-negative CRC (odds ratio=1.35, 95% confidence interval 1.22 to 1.49; Pdifference 2.1 × 10-6). The association was also stronger in tumors that were CIMP positive, MSI high, or KRAS wild type when combined (Pdifference < .001).Conclusion: Smoking was associated with differential risk of CRC subtypes defined by molecular characteristics. Heavier smokers had particularly higher risk of CRC subtypes that were CIMP positive and MSI high in combination, suggesting that smoking may be involved in the development of colorectal tumors via the serrated pathway.
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20. |
- Wang, Xiaoliang, et al.
(author)
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Mendelian randomization analysis of C-reactive protein on colorectal cancer risk
- 2019
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In: International Journal of Epidemiology. - : Oxford University Press (OUP). - 0300-5771 .- 1464-3685. ; 48:3, s. 767-780
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Journal article (peer-reviewed)abstract
- Background: Chronic inflammation is a risk factor for colorectal cancer (CRC). Circulating C-reactive protein (CRP) is also moderately associated with CRC risk. However, observational studies are susceptible to unmeasured confounding or reverse causality. Using genetic risk variants as instrumental variables, we investigated the causal relationship between genetically elevated CRP concentration and CRC risk, using a Mendelian randomization approach.Methods: Individual-level data from 30 480 CRC cases and 22 844 controls from 33 participating studies in three international consortia were used: the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT) and the Colon Cancer Family Registry (CCFR). As instrumental variables, we included 19 single nucleotide polymorphisms (SNPs) previously associated with CRP concentration. The SNP-CRC associations were estimated using a logistic regression model adjusted for age, sex, principal components and genotyping phases. An inverse-variance weighted method was applied to estimate the causal effect of CRP on CRC risk.Results: Among the 19 CRP-associated SNPs, rs1260326 and rs6734238 were significantly associated with CRC risk (P = 7.5 × 10-4, and P = 0.003, respectively). A genetically predicted one-unit increase in the log-transformed CRP concentrations (mg/l) was not associated with increased risk of CRC [odds ratio (OR) = 1.04; 95% confidence interval (CI): 0.97, 1.12; P = 0.256). No evidence of association was observed in subgroup analyses stratified by other risk factors.Conclusions: In spite of adequate statistical power to detect moderate association, we found genetically elevated CRP concentration was not associated with increased risk of CRC among individuals of European ancestry. Our findings suggested that circulating CRP is unlikely to be a causal factor in CRC development.
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21. |
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22. |
- Wang, Yifan, et al.
(author)
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Composite Data Driven-based Adaptive Control for a Piezoelectric Linear Motor
- 2022
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In: IEEE Transactions on Instrumentation and Measurement. - 1557-9662 .- 0018-9456. ; 71
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Journal article (peer-reviewed)abstract
- Piezoelectric linear motors play an important role in ultra-precision manufacturing technology. However, the complex nonlinear relationship between the input and output of the piezoelectric linear motors limits their further application. In this paper, to achieve precise motion control for a piezoelectric linear motor, a composite data driven-based adaptive control method is proposed, consisting of a correction controller, model free adaptive controller (MFAC), and low pass filter. The proposed control method addresses the demand for a precise model of the piezoelectric linear motor and solely relies on the linear model and input/output measurement data. First, an experimental test is implemented to analyze the complex nonlinearity between input and output signals of the controlled system, and a correction control is employed based on the dynamic linear sub-model of the piezoelectric linear motor to improve its dynamic and static characteristics. Then, to avoid the influence of unmodeled dynamics, such as inherent nonlinearity and external vibration, a MFAC is established as a feedback controller using data driven technology. In addition, a low pass filter is incorporated into the feedback loop to eliminate high frequency measurement noise in the system, thus improving the transient response of the MFAC method. Finally, the theoretical analysis of the error convergence is presented. The effectiveness of the proposed method is verified via comparisons with a correction control method, correction control-based digital sliding-mode control method, and correction control-based MFAC method. The experimental results indicate that the proposed control method is suitable for engineering applications. In particular, the root-mean-square error (RMSE) for the third-order S-curve tracking using the proposed is reduced by more than 15%, compared with the RMSEs for the cases with contrast control methods.
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23. |
- Wang, Yifan, et al.
(author)
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Time delay recursive neural network-based direct adaptive control for a piezo-actuated stage
- 2023
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In: Science China Technological Sciences. - 1869-1900 .- 1674-7321. ; 66:5, s. 1397-1407
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Journal article (peer-reviewed)abstract
- Piezo-actuated stage is a core component in micro-nano manufacturing field. However, the inherent nonlinearity, such as rate-dependent hysteresis, in the piezo-actuated stage severely impacts its tracking accuracy. This study proposes a direct adaptive control (DAC) method to realize high precision tracking. The proposed controller is designed by a time delay recursive neural network. Compared with those existing DAC methods designed under the general Lipschitz condition, the proposed control method can be easily generalized to the actual systems, which have hysteresis behavior. Then, a hopfield neural network (HNN) estimator is proposed to adjust the parameters of the proposed controller online. Meanwhile, a modular model consisting of linear submodel, hysteresis submodel, and lumped uncertainties is established based on the HNN estimator to describe the piezo-actuated stage in this study. Thus, the performance of the HNN estimator can be exhibited visually through the modeling results. The proposed control method eradicates the adverse effects on the control performance arising from the inaccuracy in establishing the offline model and improves the capability to suppress the influence of hysteresis on the tracking accuracy of piezo-actuated stage in comparison with the conventional DAC methods. The stability of the control system is studied. Finally, a series of comparison experiments with a dual neural networks-based data driven adaptive controller are carried out to demonstrate the superiority of the proposed controller.
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24. |
- Wang, Zhaohui, et al.
(author)
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Lightweight, Thin, and Flexible Silver Nanopaper Electrodes for High-Capacity Dendrite-Free Sodium Metal Anodes
- 2018
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In: Advanced Functional Materials. - : Wiley-Blackwell. - 1616-301X .- 1616-3028. ; 28:48
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Journal article (peer-reviewed)abstract
- Owing to its resource-abundant and favorable theoretical capacity, sodium metal is regarded as a promising anode material for sodium metal batteries. However, uncontrolled Na plating/stripping, including Na dendrite growth during cycling, has hindered its practical application. Herein, a sodiophilic, thin, and flexible silver nanopaper (AgNP) is designed based on interpenetrated nanocellulose and silver nanowires and is used as a dendrite-free Na metal electrode. Due to a network of highly conducting silver nanowire (0.6 Ω sq?1, 8200 S cm?1), the sodiophilic nature of silver, and the reduced internal strain within the flexible AgNP, a compact Na metal layer can be uniformly deposited on and reversibly stripped from the AgNP electrode without any observations of Na dendrites during cycling at 1 mA cm?2 for 800 h. As the AgNP electrode is only 2 µm thick, with a low mass loading of 0.88 mg cm?2, the AgNP?Na anode deposited with a Na deposition charge of 6 mAh cm?2 exhibits a capacity of 995 mAh g?1AgNP?Na, approaching that of a Na metal anode (1166 mAh g?1Na). The present approach provides new possibilities for the development of lightweight and stable metal batteries.
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25. |
- Xia, Zhiyu, et al.
(author)
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Functional informed genome-wide interaction analysis of body mass index, diabetes and colorectal cancer risk.
- 2020
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In: Cancer Medicine. - : Wiley. - 2045-7634. ; 9:10, s. 3563-3573
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Journal article (peer-reviewed)abstract
- BACKGROUND: Body mass index (BMI) and diabetes are established risk factors for colorectal cancer (CRC), likely through perturbations in metabolic traits (e.g. insulin resistance and glucose homeostasis). Identification of interactions between variation in genes and these metabolic risk factors may identify novel biologic insights into CRC etiology.METHODS: To improve statistical power and interpretation for gene-environment interaction (G × E) testing, we tested genetic variants that regulate expression of a gene together for interaction with BMI (kg/m2 ) and diabetes on CRC risk among 26 017 cases and 20 692 controls. Each variant was weighted based on PrediXcan analysis of gene expression data from colon tissue generated in the Genotype-Tissue Expression Project for all genes with heritability ≥1%. We used a mixed-effects model to jointly measure the G × E interaction in a gene by partitioning the interactions into the predicted gene expression levels (fixed effects), and residual G × E effects (random effects). G × BMI analyses were stratified by sex as BMI-CRC associations differ by sex. We used false discovery rates to account for multiple comparisons and reported all results with FDR <0.2.RESULTS: Among 4839 genes tested, genetically predicted expressions of FOXA1 (P = 3.15 × 10-5 ), PSMC5 (P = 4.51 × 10-4 ) and CD33 (P = 2.71 × 10-4 ) modified the association of BMI on CRC risk for men; KIAA0753 (P = 2.29 × 10-5 ) and SCN1B (P = 2.76 × 10-4 ) modified the association of BMI on CRC risk for women; and PTPN2 modified the association between diabetes and CRC risk in both sexes (P = 2.31 × 10-5 ).CONCLUSIONS: Aggregating G × E interactions and incorporating functional information, we discovered novel genes that may interact with BMI and diabetes on CRC risk.
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26. |
- Yang, Guang, et al.
(author)
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Improved Interoperability Evaluation Method for Wireless Charging Systems Based on Interface Impedance
- 2021
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In: IEEE Transactions on Power Electronics. - 0885-8993 .- 1941-0107. ; 36:8, s. 8588-8592
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Journal article (peer-reviewed)abstract
- The interoperability between the vehicle assembly (VA) and ground assembly (GA) of wireless charging systems has been specified in international standards. SAE J2954 first proposed an interoperability evaluation method based on interface impedance. However, the impedance measurement is challenging at high frequency since the phase difference between the voltage and current is not easy to measure accurately, especially when it is close to 90. Small errors in phase angle measurement are amplified in impedance calculation due to the sine/cosine function. This letter proposes an impedance measurement method using the power decomposition algorithm. By decomposing the input power into two orthogonal components, the impedance angle can be calculated without directly measuring the phase difference between the voltage and current. Thus, the measurement results of the impedance angle do not introduce errors. With the proposal, the high-cost probe or complex high-precision phase difference measurement circuit is not needed. The experimental results show that the conventional methods maximum relative error reaches 80%, making interoperability hard to determine. Reversely, with the proposed method, the relative error of impedance measurement is reduced to less than 10%.
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27. |
- Zheng, Siyu, et al.
(author)
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Strong Coupling of Colloidal Quantum Dots via Self-Assemble Passivation for Efficient Infrared Solar Cells
- 2021
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In: Advanced Materials Interfaces. - : John Wiley & Sons. - 2196-7350. ; 8:13
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Journal article (peer-reviewed)abstract
- The surface passivation of colloidal quantum dots (CQD) is critical for the electronic coupling of CQDs, which significantly affects the photovoltaic performance of CQD solar cells (CQDSCs). Herein, a self-assemble passivation (SAP) strategy of CQDs is introduced to improve CQD coupling. The PbI2 passivation layer prepared using the SAP method can largely improve surface defect passivation of CQDs, diminishing charge recombination induced by the sub-bandgap traps. Meanwhile, extensive theoretical simulations reveal that the self-assembled PbI2 passivation layer works as a "charger bridge" for charge transport between the adjacent CQDs, avoiding CQD fusion. The infrared CQDSCs are fabricated and the SAP-based CQDSC yields an efficiency of up to 12.3%, which is significantly improved compared with that of the conventional CQDSCs with iodide passivating CQD surface. The improved photovoltaic performance in the SAP-based CQDSCs is attributed to increased charge extraction, resulting from strong CQD coupling within the CQD solid films. This work provides a simple and facile way to improve the electronic coupling of CQDs for high-performance infrared CQDSCs.
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