Strain Engineering for Enhanced P-channel Field Effect Transistor Performance

Master'sMASTER OF ENGINEERIN

Isolation and Identification of Pathogen from Fresh Walnut and the Inhibition Effect of Chlorine Dioxide

Fresh walnuts have short shelf life due to they are prone to mildew, which greatly limits their circulation distance and economic benefits. In this paper, the effect of chlorine dioxide (ClO2) on the control of mildew was studied by isolation and reinfection of pathogens, morphological and molecular identification, in vitro and in vivo antibacterial tests, and quality evaluation of fresh walnuts after treatment using 'Qingxiang' walnuts as test materials. The results showed that there were two main pathogens isolated from the mildew zone of fresh walnuts, Penicillium sp and Aspergillus tabinus, and two main pathogens isolated from the sticky zone of fresh walnuts, Pseudomonas eucalyptus and Micrococcus flavus. In vitro, fumigation with 0~40 mg/L ClO2 had a significant dose-effect relationship on the inhibition of these four pathogens. The IC50 value of the action was between 7 and 20 mg/L. ClO2 of 16, 30 and 40 mg/L inhibited the propagation and growth of Penicillium sp, Aspergillus tabinus and two kinds of bacteria in vitro by 100%. The antibacterial role of slow-release ClO2 fumigant presented by inhibiting both the germination of mold spores and mycelium growth. 40 mg/L ClO2 fumigation significantly (P<0.05) reduced the fungal and bacterial colonies of fresh walnuts during shelf life at 25 and 5 ℃, maintaining better sensory quality, and extending the consumer acceptance period of fresh walnuts to 12 days at 25 ℃ and 48 days at 5 ℃. The combined use of walnut green peel extract (GE) had no significant improvement on the ClO2 preservation effect. 40 mg/L ClO2 fumigation has been identified as a convenient and efficient shelf life preservation technology for fresh walnuts

Learning Representative Features by Deep Attention Network for 3D Point Cloud Registration

Three-dimensional point cloud registration, which aims to find the transformation that best aligns two point clouds, is a widely studied problem in computer vision with a wide spectrum of applications, such as underground mining. Many learning-based approaches have been developed and have demonstrated their effectiveness for point cloud registration. Particularly, attention-based models have achieved outstanding performance due to the extra contextual information captured by attention mechanisms. To avoid the high computation cost brought by attention mechanisms, an encoder–decoder framework is often employed to hierarchically extract the features where the attention module is only applied in the middle. This leads to the compromised effectiveness of the attention module. To tackle this issue, we propose a novel model with the attention layers embedded in both the encoder and decoder stages. In our model, the self-attentional layers are applied in the encoder to consider the relationship between points inside each point cloud, while the decoder utilizes cross-attentional layers to enrich features with contextual information. Extensive experiments conducted on public datasets prove that our model is able to achieve quality results on a registration task

Alterations in Patients With First-Episode Depression in the Eyes-Open and Eyes-Closed Conditions: A Resting-State EEG Study

Altered resting-state EEG activity has been repeatedly reported in major depressive disorder (MDD), but no robust biomarkers have been identified until now. The poor consistency of EEG alterations may be due to inconsistent resting conditions; that is, the eyes-open (EO) and eyes-closed (EC) conditions. Here, we explored the effect of the EO and EC conditions on EEG biomarkers for discriminating MDD subjects and healthy control (HC) subjects. EEG data were recorded from 30 first-episode MDD and 26 HC subjects during an 8-min resting-state session. The features were extracted using spectral power, Lempel&#x2013;Ziv complexity, and detrended fluctuation analysis. Significant features were further selected via the sequential backward feature selection algorithm. Support vector machine (SVM), logistic regression, and linear discriminate analysis were used to determine a better resting condition to provide more reliable estimates for identifying MDD. Compared with the HC group, we found that the MDD group exhibited widespread increased $\beta$ and $\gamma$ powers ( {p} < 0.01 ) in both conditions. In the EO condition, the MDD group showed increased complexity and scaling exponents in the $\alpha$ band relative to HC subjects ( {p} < 0.05 ). The best classification performance of the combined feature sets was found in the EO condition, with the leave-one-out classification accuracy of 89.29&#x0025;, sensitivity of 90.00&#x0025;, and specificity of 88.46&#x0025; using SVM with the linear kernel classifier when the threshold was set to 0.7, followed by the $\beta$ and $\gamma$ spectral features with an average accuracy of 83.93&#x0025;. Overall, EO and EC conditions indeed affected the between-group variance, and the EO condition is suggested as the more separable resting condition to identify depression. Specially, the $\beta$ and $\gamma$ powers are suggested as potential biomarkers for first-episode MDD

Ore-fluid geochemistry of the Hehuashan Pb–Zn deposit in the Tongling ore district, Anhui province, China: evidence from REE and C–H–O isotopes of calcite

Calcite is the main gangue mineral of the Hehuashan lead–zinc deposit, which is located in the Tongling ore district, Anhui Province, East China. The ore bodies of the Hehuashan deposit are hosted by dissolution breccia of the Lower Triassic carbonate sediments. We report petrography, rare earth elements (REE), and C–H–O isotope data of four generations of calcite recognized in the Hehuashan deposit, namely the pre-ore stage calcite (Cal-1), early ore-forming stage calcite (Cal-2), late ore-forming stage calcite (Cal-3) and post-ore stage calcite (Cal-4). In addition, we also report C–H–O isotopes data of dolostone from the Lower Triassic carbonate sediments. All four calcite generations show a low ∑REE content (13–50 ppm on average), indicating that the related ore-forming fluids may not have been derived a magmatic fluid but rather be derived from the carbonate sediments or basinal brines. Low LREE/HREE ratio (1.1–6.1 on average) of all four calcite generations implies that no significant REE fractionation happened during the mineralizing processes. The wide distribution of Y/Ho ratios (17–70) of calcite indicates a result of fluids mixing. The δ¹³C values of calcite (1.4‰ to 4.2‰) are comparable to marine carbonates, but the δ¹⁸O values are lower, indicating possibly a result of carbonates dissolution. Calculated δ¹⁸O of the fluid in equilibrium with calcite vary from –3.1‰ to –0.1‰, combining the δDV-SMOW (–100‰ to –81‰), implying a fluid mixing of a brine fluid and meteoric water or diagenetic pore water for the mineralization of the Hehuashan deposit