183 research outputs found
In Situ Biodiesel Production from Fast-Growing and High Oil Content Chlorella pyrenoidosa in Rice Straw Hydrolysate
Rice straw hydrolysate was used as lignocellulose-based carbon source for Chlorella pyrenoidosa cultivation and the feasibility of in situ biodiesel production was investigated. 13.7 g/L sugar was obtained by enzymatic hydrolyzation of rice straw. Chlorella pyrenoidosa showed a rapid growth in the rice straw hydrolysate medium, the maximum biomass concentration of 2.83 g/L was obtained in only 48 hours. The lipid content of the cells reached as high as 56.3%. In situ transesterification was performed for biodiesel production. The optimized condition was 1 g algal powder, 6 mL n-hexane, and 4 mL methanol with 0.5 M sulfuric acid at the temperature of 90°C
in 2-hour reaction time, under which over 99% methyl ester content and about 95% biodiesel yield were obtained. The results suggested that the method has great potential in the production of biofuels with lignocellulose as an alternative carbon source for microalgae cultivation
RNA interference as a gene silencing therapy for mutant MYOC protein in primary open angle glaucoma
MetaAge: Meta-Learning Personalized Age Estimators
Different people age in different ways. Learning a personalized age estimator
for each person is a promising direction for age estimation given that it
better models the personalization of aging processes. However, most existing
personalized methods suffer from the lack of large-scale datasets due to the
high-level requirements: identity labels and enough samples for each person to
form a long-term aging pattern. In this paper, we aim to learn personalized age
estimators without the above requirements and propose a meta-learning method
named MetaAge for age estimation. Unlike most existing personalized methods
that learn the parameters of a personalized estimator for each person in the
training set, our method learns the mapping from identity information to age
estimator parameters. Specifically, we introduce a personalized estimator
meta-learner, which takes identity features as the input and outputs the
parameters of customized estimators. In this way, our method learns the meta
knowledge without the above requirements and seamlessly transfers the learned
meta knowledge to the test set, which enables us to leverage the existing
large-scale age datasets without any additional annotations. Extensive
experimental results on three benchmark datasets including MORPH II, ChaLearn
LAP 2015 and ChaLearn LAP 2016 databases demonstrate that our MetaAge
significantly boosts the performance of existing personalized methods and
outperforms the state-of-the-art approaches.Comment: Accepted by IEEE Transactions on Image Processing (TIP
Observation of short-lived local polar states induced by applied tip biases in BaTiO3-based relaxor ferroelectric ceramics
Using piezoresponse force microscopy imaging and spectroscopy methods, surface polar states induced by applied tip biases in the ergodic/paraelectric phase of a BaTiO3-based relaxor ferroelectric ceramic have been observed. The induced polar state appears to be short-lived (typical lifetime only a few seconds) and dependent on the voltages applied and their duration. The observed piezoresponse hysteresis and relaxation behavior is primarily interpreted with respect to the picture of the polar nano-region dynamics, as proposed for lead-based relaxors. Spatially resolved piezoresponse relaxation mapping reveals the presence of sub-micron correlated features, presumably due to A-site chemical inhomogeneity as supported by site-correlated elemental mapping microanalysis.Q.L., Y.L., and R.L.W., acknowledge the support of the
Australian Research Council (ARC) in the form of ARC
Discovery Grants. Y.L. also acknowledges support from the
ARC Future Fellowships Program
Heightened expression of MICA enhances the cytotoxicity of NK cells or CD8+T cells to human corneal epithelium in vitro
BACKGROUND: Major-histocompatibility-complex class I-related chain A (MICA) antigens are the ligands of NKG2D, which is an activating or coactivating receptor expressed on human NK cells and CD8(+)T cells. We sought to determine whether MICA expression in human corneal epithelium (HCE) could affect the cytotoxicity mediated by NK cells or CD8(+)T cells. METHODS: Cell cultures of HCE were harvested from human donor eyes. Flow cytometric analysis and ELISA was performed to determine the levels of MICA expression on HCE. Then, HCE was transfected with a lentivirus vector expressing MICA and GFP. Flow cytometric analysis, RT-PCR, western blot and ELISA were performed to check the levels of MICA expression. For cytotoxicity testing, allogeneic NK cells and CD8(+)T cells were isolated from peripheral blood mononuclear cells of healthy volunteers by magnetic cell sorting. The cytolytic activity of NK cells and CD8(+)T cells was assessed against MICA-transfected HCE (NK cells: E:T ratio = 3:1; CD8(+)T cells: E:T ratio = 10:1) using the nonradioactive cytotoxicity detection kit lactate deshydrogenase. RESULTS: Surface expression of MICA on corneal epithelium was identified at a low level. A cell line of stable human MICA-transfected corneal epithelium was successfully established. Heightened expression of MICA on HCE was found to promote the cytotoxicity mediated by NK cells or CD8(+)T cells, which could be blocked by an anti-MICA antibody. CONCLUSION: MICA molecules may contribute to cytotoxic responses mediated by activated immune effector cells in corneal epithelium immunity
Fat-mass and obesity-associated gene polymorphisms and weight gain after risperidone treatment in first episode schizophrenia
BACKGROUND: Obesity induced by antipsychotics severely increases the risk of many diseases and significantly reduces quality of life. Genome Wide Association Studies has identified fat-mass and obesity-associated (FTO) gene associated with obesity. The relationship between the FTO gene and drug-induced obesity is unclear.
METHOD: Two hundred and fifty drug naive, Chinese Han patients with first-episode schizophrenia were enrolled in the study, and genotyped for four single nucleotide polymorphisms (SNPs rs9939609, rs8050136, rs1421085 and rs9930506) by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing. Body weight and body mass index (BMI) were measured at baseline and six months after risperidone treatment.
RESULTS: At baseline, body weight and BMI of TT homozygotes were lower than those of A allele carriers in rs9939609; body weight of AA homozygotes was higher than those of G allele carriers in rs9930506 (p\u27s \u3c 0.05). After 6 months of risperidone treatment, body weight and BMI of TT homozygotes were lower than those of A allele carriers in rs9939609 (p\u27s \u3c 0.01); body weight and BMI of CC homozygotes were lower than those of A allele carriers in rs8050136 (p\u27s \u3c 0.05); body weight of AA homozygotes was higher than those of G allele carriers in rs9930506 (p\u27s \u3c 0.05). After controlling for age, gender, age of illness onset, disease duration, weight at baseline and education, weight gain of TT homozygotes at 6 months remained to be lower than those of A allele carriers in rs9939609 (p \u3c 0.01); weight gain of CC homozygotes at 6 months was lower than those of A allele carriers in rs8050136 (p = 0.01). Stepwise multiple regression analysis suggested that, among 4 SNPs, rs9939609 was the strongest predictor of weight gain after 6 months of risperidone treatment (p = 0.001).
CONCLUSIONS: The FTO gene polymorphisms, especially rs9939609, seem to be related to weight gain after risperidone treatment in Chinese Han patients with first episode schizophrenia
Screening and optimization of low-cost medium for Pseudomonas putida Rs-198 culture using RSM
Robust Hybrid Algorithm of PSO and SOCP for Grating Lobe Suppression and against Array Manifold Mismatch
Based on Particle Swarm Optimization (PSO) and Second-Order Cone Programming (SOCP) algorithm, this paper proposes a hybrid optimization method to suppress the grating lobes of sparse arrays and improve the robustness of array layout. With the peak side-lobe level (PSLL) as the objective function, the paper adopts the particle swarm optimization as a global optimization algorithm to optimize the elements’ positions, the convex optimization as a local optimization algorithm to optimize the elements’ weights. The effectiveness of the grating lobes suppression (as low as -32.13 dB) by this method is illustrated through its application to the sparse linear array when the actual steering vector is known. To enhance the robustness of the optimized array, a rebuilt robust convex optimization model is adopted in the optimization of both array excitations and layout. When the array manifold mismatch error is 1cm, the PSLL by the robust algorithm can be compressed to -27dB, compared to that of -24dB by the ordinary optimization. Results of a set of representative numerical experiments show that the algorithm proposed in this paper can obtain a more robust array layout and matched elements’ weight coefficients to avoid the huge degradation of the array pattern performance in the presence of array manifold mismatch errors. The good performance of pattern synthesis demonstrates the effectiveness of the proposed robust algorithm
- …