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1.
Sensors (Basel) ; 19(18)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514321

RESUMO

It is significant to identify rock-mineral microscopic images in geological engineering. The task of microscopic mineral image identification, which is often conducted in the lab, is tedious and time-consuming. Deep learning and convolutional neural networks (CNNs) provide a method to analyze mineral microscopic images efficiently and smartly. In this research, the transfer learning model of mineral microscopic images is established based on Inception-v3 architecture. The four mineral image features, including K-feldspar (Kf), perthite (Pe), plagioclase (Pl), and quartz (Qz or Q), are extracted using Inception-v3. Based on the features, the machine learning methods, logistic regression (LR), support vector machine (SVM), random forest (RF), k-nearest neighbors (KNN), multilayer perceptron (MLP), and gaussian naive Bayes (GNB), are adopted to establish the identification models. The results are evaluated using 10-fold cross-validation. LR, SVM, and MLP have a significant performance among all the models, with accuracy of about 90.0%. The evaluation result shows LR, SVM, and MLP are the outstanding single models in high-dimensional feature analysis. The three models are also selected as the base models in model stacking. The LR model is also set as the meta classifier in the final prediction. The stacking model can achieve 90.9% accuracy, which is higher than all the single models. The result also shows that model stacking effectively improves model performance.

2.
Science ; 352(6289): 1065, 2016 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-27230369
3.
Genetics ; 202(1): 175-89, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26534952

RESUMO

To grow, insects must periodically shed their exoskeletons. This process, called ecdysis, is initiated by the endocrine release of Ecdysis Trigger Hormone (ETH) and has been extensively studied as a model for understanding the hormonal control of behavior. Understanding how ETH regulates ecdysis behavior, however, has been impeded by limited knowledge of the hormone's neuronal targets. An alternatively spliced gene encoding a G-protein-coupled receptor (ETHR) that is activated by ETH has been identified, and several lines of evidence support a role in ecdysis for its A-isoform. The function of a second ETHR isoform (ETHRB) remains unknown. Here we use the recently introduced "Trojan exon" technique to simultaneously mutate the ETHR gene and gain genetic access to the neurons that express its two isoforms. We show that ETHRA and ETHRB are expressed in largely distinct subsets of neurons and that ETHRA- but not ETHRB-expressing neurons are required for ecdysis at all developmental stages. However, both genetic and neuronal manipulations indicate an essential role for ETHRB at pupal and adult, but not larval, ecdysis. We also identify several functionally important subsets of ETHR-expressing neurons including one that coexpresses the peptide Leucokinin and regulates fluid balance to facilitate ecdysis at the pupal stage. The general strategy presented here of using a receptor gene as an entry point for genetic and neuronal manipulations should be useful in establishing patterns of functional connectivity in other hormonally regulated networks.


Assuntos
Drosophila melanogaster/embriologia , Muda/fisiologia , Isoformas de Proteínas , Receptores de Peptídeos/fisiologia , Animais , Animais Geneticamente Modificados , Feminino , Hormônios de Inseto/fisiologia , Masculino , Neurônios/fisiologia , Isoformas de Proteínas/fisiologia , Pupa/fisiologia , Receptores de Peptídeos/genética
4.
J Environ Manage ; 145: 349-56, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25113229

RESUMO

The debate on the relationship between corporate or industrial environmental performance (EP) and financial performance (FP) has yet to be resolved, and studies need to examine the possible moderating effects on the EP-FP link. We argue that industrial EP has a positive effect on FP and that industrial munificence and resource slack can moderate the EP-FP link. Using a dataset from Chinese industrial firms, we examine the direct effect of industrial EP on FP and the indirect effects of industrial munificence and resource slack on the EP-FP link. Our results show that improving corporate or industrial-level EP significantly influences FP and that slack resources play a significant role on the EP-FP link. However, we found no significant moderating effect of industrial munificence on the link.


Assuntos
Conservação dos Recursos Naturais/economia , Política Ambiental/economia , Poluição Ambiental/economia , Poluição Ambiental/prevenção & controle , Indústrias/economia , China , Conservação dos Recursos Naturais/métodos , Custos e Análise de Custo , Bases de Dados Factuais , Indústrias/organização & administração
5.
J Environ Manage ; 145: 357-67, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25113230

RESUMO

Based on a content analysis of 533 Chinese listed companies, this study examines how corporate environmental performance affects not only the level of detail of a company's environmental disclosures, but also what information is disclosed. The results show that (1) both poor and good performers have more disclosure than the median (i.e., "mixed") performers, which provides empirical evidence to support a nonlinear relationship between corporate environmental performance and environmental disclosure; (2) poor performers disclose more soft information on environmental performance than good performers, and good performers disclose more solid information; and (3) although poor performers increase disclosure after being exposed as environmental violators, they avoid disclosing negative environmental information, such as the violation and the associated penalties. This study provides additional evidence for a nonlinear relationship between environmental performance and disclosure in emerging markets, and suggests environmental disclosure may not be a valid signal to differentiate good performers from poor performers in contemporary China.


Assuntos
Conservação dos Recursos Naturais , Revelação , Política Ambiental , Indústrias , Modelos Teóricos , China , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Bases de Dados Factuais , Indústrias/economia , Indústrias/legislação & jurisprudência , Projetos de Pesquisa
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