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关键词： 人防工程   平战结合   应急检验   实际应用情况   应战   探索建立   场所  

摘要： 人防工程拥有场所优势,大部分人防工程在应急支接中能找到对应的“角色”。但由于种种原因,实际应用情况并不理想。新时期人防工程建设发展需要进一步深化融合,在原有“平战结合”的基础上,探索建立人防工程应战、应急、服务一体化发展模式。

关键词： Post-first year summer experiences   Cultural and social capital   Undergraduate research   Internship   Paid work   Volunteering  

摘要： Students may have experiences that relate to long-term retention and success during the summer after completing their first year in college. Research shows that college students' engagement and success varies based on their cultural and social capital. However, there is a dearth of research on how their cultural and social capital is associated with college students' summer experiences after they complete their first year. The purpose of this study is to better understand the ways that students' cultural and social capital-as measured through relationships with parents and faculty-relate to their participation in undergraduate research, internships, paid work, or volunteering after the first year of college. We analyzed longitudinal data from 1,066 students at three universities using data from the Pathways through College Study. We found that students who had parents with graduate or professional degrees had higher odds of participating in summer undergraduate research and internships, compared to first-generation college students. Students who had interactions with faculty outside of the classroom also had higher odds of participating in the four summer experiences, but the relationship between parental education and post-first year experiences do not vary depending on the level of faculty interactions. This study offers implications for faculty and student affairs practitioners related to encouraging students to participate in post-first year summer opportunities, particularly students with less social and cultural capital through their parents or faculty.

关键词： DSC   Exhaustive exercise   Protein denaturation   Special forces  

摘要： The human blood plasma proteome profile has been an area of intensive investigation and differential scanning calorimetry (DSC) has come forward as a novel tool in analyzing plasma heat capacity changes to monitor various physiological responses in health and disease. This study used DSC to assess potential alterations in the plasma heat capacity profile of albumin and globulins during extremely demanding physical exercise. We monitored the changes in denaturation profiles of those plasma proteins for five consecutive days of an extraordinary exercise training schedule in 14 young male Special Forces volunteers, as well as after a 30-day recovery period. The major effect of the prolonged intense exercise was the continuous upward shift of the albumin peak by 2??3 ?C on the initial days of exercise, with a tendency to plateau circa the 5th day of exercise. In addition, some redistribution of the denaturational enthalpy was observed upon exercise, where the globulins peak increased relative to the albumin peak. Noteworthy, the alterations in the plasma proteome denaturational profiles were not persistent, as virtually full recovery of the initial status was observed after 30 days of recovery. Our findings indicate that 5 days of exhaustive physical exercise of highly trained individuals enhanced the thermal stability of plasma albumin shifting its denaturational transition to higher temperatures. We surmise that these effects may be a result of increased blood oxygenation during the prolonged intense exercise and, consequently, of albumin oxidation as part of the overall adaptation mechanisms of the body to extreme physical and/ or oxidative stress.

关键词： hyperspectral classification   data augmentation   structural features   small sample classification  

摘要： For both traditional classification and current popular deep learning methods, the limited sample classification problem is very challenging, and the lack of samples is an important factor affecting the classification performance. Our work includes two aspects. First, the unsupervised data augmentation for all hyperspectral samples not only improves the classification accuracy greatly with the newly added training samples, but also further improves the classification accuracy of the classifier by optimizing the augmented test samples. Second, an effective spectral structure extraction method is designed, and the effective spectral structure features have a better classification accuracy than the true spectral features.

关键词： Zero shot learning   Pseudo-sample synthesis   Style transfer   Deep learning   Side-scan sonar image classification  

摘要： Side-scan sonar (SSS) is the most important sensor in the field of ocean exploration, auto-detection of targets in SSS images is very critical. Deep neural networks (DNNs) have exhibited impressive performance but require very large number of training samples;only a limited number of SSS images will not suffice. In more extreme cases, no appropriate SSS image is available for some specific targets that need to be identified, making it impossible to train DNNs. In this paper, we deal with such extreme situations, how can a DNN recognize targets in SSS images without any training samples? which is the "zero-shot learning problem." Inspired by the way humans perceive the world, we develop a zero-shot SSS image classification method through synthesis of pseudo SSS images. For a given category, we use a fixed style-transfer method to synthesize pseudo samples using common optical images and any available SSS images, and train the DNN with these pseudo samples. The zero-shot learning problem thus can be transformed to a conventional supervised learning problem. Experimental results showed we can achieve excellent classification ability even if no training samples are available. The source code is available at https://***/guizilaile23/ZSL-SSS. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： fluorine   oxidative fluorination   oxalyl chloride   phosphorus   trichloroisocyanuric acid  

摘要： A mild, oxidative fluorination approach to a variety of fluorinated phosphorus compounds using trichloroisocyanuric acid (TCICA) and KF was developed as a complement to a recent study on deoxygenative fluorination using oxalyl chloride. Herein, the syntheses of several fluorinated organophosphorus compounds are reported, and both TCICA/KF and oxalyl chloride/KF conditions are compared and contrasted throughout. Initial investigations of the method on other group 15 heteroatoms (i. e., As, Sb, and Bi) are also reported, with varied success. This work notably extends the known TCICA/KF reactivity series to another group of elements beyond previously studied chalcogens (S, Se, and Te) and halogens (iodine) and expands the utility of the previously reported oxalyl chloride/KF method.

关键词： SERS   Double cross-validation   PCA-LDA   Serum   Hepatocellular carcinoma  

摘要： Intense label-free surface-enhanced Raman scattering (SERS) spectra of serum samples were rapidly obtained on Ag plasmonic paper substrates upon 785 nm excitation. Spectra from the hepatocellular carcinoma (HCC) patients showed consistent differences with respect to those of the control group. In particular, uric acid was found to be relatively more abundant in patients, while hypoxanthine, ergothioneine, and glutathione were found as relatively more abundant in the control group. A repeated double cross-validation (RDCV) strategy was applied to optimize and validate principal component analysis-linear discriminant analysis (PCA-LDA) models. An analysis of the RDCV results indicated that a PCA-LDA model using up to the first four principal components has a good classification performance (average accuracy was 81%). The analysis also allowed confidence intervals to be calculated for the figures of merit, and the principal components used by the LDA to be interpreted in terms of metabolites, confirming that bands of uric acid, hypoxanthine, ergothioneine, and glutathione were indeed used by the PCA-LDA algorithm to classify the spectra.

关键词： Multimodal interaction analysis   Primary science education   Dialogic   Multilingual contexts   Plurilingual students  

摘要： Science teaching and learning are discursive practices, yet analysis of these practices has frequently been grounded in theorizations that place language at the forefront of interaction and meaning-making. Such language-centric analytic approaches risk overlooking key embodied, enacted aspects of students' engagement in science practices. This manuscript presents a case of a plurilingual student's participation in science inquiry to demonstrate how multimodal interaction analysis can be used to examine the highly diverse array of communicative resources that she draws upon while participating in science, including gestures, facial expressions, vocal intonations, and languages. Grounded in dialogic theorizations of language, we first detail the multimodal interaction approach, and second, we show how multimodal interaction analysis beginning first with her embodied engagement, then coupled with her subsequent written and spoken engagement, reveals robust views of her engagement in science practices. Key to this methodological approach is multilayered analysis that backgrounds verbal or spoken communication to allow for an identification of embodied interaction resources employed. We emphasize how this analytical method allows us to conceptualize science as a practice that unfolds through and in interaction, as compared to a static body of concepts to be learned.

关键词： Discourse analysis   STEM education   Small group learning   Positioning theory   Activity theory   Power  

摘要： Integrated science, technology, engineering, and mathematics (STEM) education is becoming increasingly common in K-12 classrooms, and small group activities are ubiquitous to STEM instruction. This article includes both theoretical and practical descriptions of a microethnographic approach to critical multimodal discourse analysis that we used to explore power and positioning within a mixed-gender group of students working together on an engineering design challenge. We drew upon social semiotics, positioning theory, and activity theory to ground this work and utilized three phases of data analysis: microethnography to develop individual and group storylines, critical multimodal discourse analysis of key events, and the integration of storylines and discourse analysis. This multi-phase approach granted us insights into our data that would have otherwise been lacking. Microethnography revealed the significance of the shift between science and engineering activities in relation to power and positioning within the group. Multimodal analysis revealed that the introduction of new physical artifacts influenced power and positioning within the small group, with different modes of communication having different intensities across the unit. We argue that our approach is useful in analyzing complex small group interactions within science classrooms and highlight key methodological decisions for researchers interested in employing a microethnographic approach to critical multimodal discourse analysis.