Density reduction has become a topical issue in wood composite materials for application in building and furniture. In this study, lightweight wood–polyurethane (W–PU) composite foams with the ...addition of 30 wt% wood particles were prepared. Industrial kraft lignin was used as bio-polyol to substitute partial petroleum-based diethylene glycol (DEG) to synthesize rigid W–PU foams. The effect of varying lignin contents (5, 10, 15 and 20 wt% based on DEG mass) on the reactivity, morphology, density, compressive properties, water absorption and thermal stability of the foams was evaluated. Fourier transform infrared (FTIR) analysis confirmed the formation of characteristic urethane linkages in all the foam samples. With the incorporation of lignin, the foam cellular shape became irregular with formation of large cells. W–PU foams exhibited poor cellular structures with a larger number of open cells. The density of W–PU foams increased from 47 to 96 kg/m
3
as the lignin content increased from 0 to 20%. Although the foam reactivity was decreased by the incorporation of lignin, both the compressive strength and modulus were increased upon the incorporation of lignin. Furthermore, the specific compressive strength and modulus of W–PU foams increased by 55% and 48% with lignin content increasing from 0 to 20%, and the 20-day water absorption decreased by 38%. Thermal gravimetric analysis showed that the incorporation of lignin did not significantly affect the thermal degradation behaviour of foam, but it rather increased the mass of char residue. This study provides a promising method for value-added utilization of technical lignin in W–PU lightweight composites.
This paper surveys intelligent routing protocols which contribute to the optimization of network lifetime in wireless sensor networks (WSNs). Different from other surveys on routing protocols for ...WSNs, this paper first puts forward new ideas on the definition of network lifetime. Then, with a view to prolonging network lifetime, it discusses the routing protocols based on such intelligent algorithms as reinforcement learning (RL), ant colony optimization (ACO), fuzzy logic (FL), genetic algorithm (GA), and neural networks (NNs). Intelligent algorithms provide adaptive mechanisms that exhibit intelligent behavior in complex and dynamic environments like WSNs. Inspired by such an idea, some intelligent routing protocols have recently been designed for WSNs. Under each category, it discusses the representative routing algorithms and further analyzes the performance of network lifetime defined in three aspects. This paper intends to give assistance in the optimization of network lifetime in WSNs, together with offering a guide for the collaboration between WSNs and computational intelligence (CI).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Rater effects, or raters’ tendencies to assign ratings to performances that are different from the ratings that the performances warranted, are well documented in rater-mediated assessments across a ...variety of disciplines. In many real-data studies of rater effects, researchers have reported that raters exhibit more than one effect, such as a combination of misfit and systematic biases related to student subgroups (i.e., differential rater functioning DRF). However, researchers who conduct simulation studies of rater effects usually focus on the effects in isolation. The purpose of this study was to explore the degree to which rater effect indicators are sensitive to rater effects when raters exhibit more than one type of effect, and to explore the degree to which this sensitivity changes under different data collection designs. We used a simulation study to explore combinations of DRF and rater misfit. Overall, our findings suggested that it is possible to use common numeric and graphical indicators of DRF and rater misfit when raters exhibit both these effects, but that these effects may be difficult to distinguish using only numeric indicators. We also observed that combinations of rater effects are easier to identify when complete rating designs are used. We discuss implications of our findings as they result to research and practice.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK, VSZLJ
A Cu-catalyzed asymmetric ring-opening reaction of five-membered diaryliodonium salts and oximes is introduced. The reactions undergo selective N-arylation of oximes and provide an efficient protocol ...for the synthesis of atropisomeric nitrones. The optically active nitrones, serving as versatile intermediates, were converted to diversely functionalized axially chiral aniline derivatives and N-heterocycles.
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IJS, KILJ, NUK, PNG, UL, UM
Persistent organic pollutants (POPs) present in foods have been a major concern for food safety due to their persistence and toxic effects. To ensure food safety and protect human health from POPs, ...it is critical to achieve a better understanding of POP pathways into food and develop strategies to reduce human exposure. POPs could present in food in the raw stages, transferred from the environment or artificially introduced during food preparation steps. Exposure to these pollutants may cause various health problems such as endocrine disruption, cardiovascular diseases, cancers, diabetes, birth defects, and dysfunctional immune and reproductive systems. This review describes potential sources of POP food contamination, analytical approaches to measure POP levels in food and efforts to control food contamination with POPs.
Home-purchase limit is a unique administrative housing policy of China and has non-negligible influences on the housing price. The objective of this study is to analyze the spillover effect of ...home-purchase limit policy on housing prices in 35 large and medium-sized cities. The panel data of these cities and the spatial Durbin model are employed in this study. The results indicate that the spillover effect of home-purchase limit policy is positive and significant in all of 35 cities. However, when we categorize these cities into high-risk, medium-risk, and low-risk based on housing price characteristics, the spillover effect of home-purchase limit policy is different. It is not significant in high-risk cities, is negatively significant in medium-risk cities, and is positively significant in low-risk cities. This paper suggests that local governments can pay more attention to the precise design and implementation of home-purchase limit policy, and maintain policy continuity to avoid further spillover fluctuations in housing prices.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The origin of agricultural products is crucial to their quality and safety. This study explored the differences in chemical composition and structure of rice from different origins using fluorescence ...detection technology. These differences are mainly affected by climate, environment, geology and other factors. By identifying the fluorescence characteristic absorption peaks of the same rice seed varieties from different origins, and comparing them with known or standard samples, this study aims to authenticate rice, protect brands, and achieve traceability. The study selected the same variety of rice seed planted in different regions of Jilin Province in the same year as samples. Fluorescence spectroscopy was used to collect spectral data, which was preprocessed by normalization, smoothing, and wavelet transformation to remove noise, scattering, and burrs. The processed spectral data was used as input for the long short-term memory (LSTM) model. The study focused on the processing and analysis of rice spectra based on NZ-WT-processed data. To simplify the model, uninformative variable elimination (UVE) and successive projections algorithm (SPA) were used to screen the best wavelengths. These wavelengths were used as input for the support vector machine (SVM) prediction model to achieve efficient and accurate predictions. Within the fluorescence spectral range of 475-525 nm and 665-690 nm, absorption peaks of nicotinamide adenine dinucleotide (NADPH), riboflavin (B2), starch, and protein were observed. The origin tracing prediction model established using SVM exhibited stable performance with a classification accuracy of up to 99.5%.The experiment demonstrated that fluorescence spectroscopy technology has high discrimination accuracy in tracing the origin of rice, providing a new method for rapid identification of rice origin.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In the field of nutritional epidemiology, principal component analysis (PCA) has been used extensively in identifying dietary patterns. Recently, compositional data analysis (CoDA) has emerged as an ...alternative approach for obtaining dietary patterns. We aimed to directly compare and evaluate the ability of PCA and principal balances analysis (PBA), a data-driven method in CoDA, in identifying dietary patterns and their associations with the risk of hypertension.
Cohort study. A 24-h dietary recall questionnaire was used to collect dietary data. Multivariate logistic regression analysis was used to analyse the association between dietary patterns and hypertension.
2004 and 2009 China Health and Nutrition Survey.
A total of 3892 study participants aged 18-60 years were included as the subjects.
PCA and PBA identified five patterns each. PCA patterns comprised a linear combination of all food groups, whereas PBA patterns included several food groups with zero loadings. The coarse cereals pattern identified by PBA was inversely associated with hypertension risk (highest quintile: OR = 0·74 (95 % CI 0·57, 0·95);
= 0·037). None of the five PCA patterns was associated with hypertension. Compared with the PCA patterns, the PBA patterns were clearly interpretable and accounted for a higher percentage of variance in food intake.
Findings showed that PBA might be an appropriate and promising approach in dietary pattern analysis. Higher adherence to the coarse cereals dietary pattern was associated with a lower risk of hypertension. Nevertheless, the advantages of PBA over PCA should be confirmed in future studies.
The enabling electrohydrodynamic (EHD) printing technology in a one-step forming, continuous, and controllable manner has gained wide attention in the field of flexible printed electronics. The ...evaporation characteristic of ink solvent during the EHD printing greatly affects the shape of the jet as well as the penetration and diffusion of inks on fabrics, which is crucial to the formation of high-quality printed electronics. However, few works have deeply investigated the control of ink solvent evaporation to adjust the formability of EHD printing electronics on rough and porous textiles. Here, conductive inks with different solvent evaporation rates are formulated. The effect of solvent evaporation on the motion of inks is evaluated by the contact angle over time. Furthermore, the morphology and electrical properties under different deformation of EHD-printed conductive lines are observed and measured. The results show that the morphology of conductive lines printed on fabric could be accurately controlled by the ratios of the solvent in inks, and the solvent evaporation rate has a significant inverse-parabolic effect on electrical resistance and its stability under deformation. Moreover, the serviceability of the optimal ink is demonstrated by the performance of an EHD-printed antenna for ultra-high frequency radio frequency identification tags, and its maximum reading range is 9.1 m under typical application examples. These findings will provide a guide for ink formulation and process control of EHD printing in flexible textile-based electronics.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
Cu in surface waters has been demonstrated to affect aquatic animals at ecologically relevant concentrations. However, its effects on reproductive endocrine system and the underlying toxicological ...mechanisms are largely unknown. In this study, zebrafish (Danio rerio) were exposed to 0, 10, 20, 40 μg/L of Cu for 30 days. Growth, gonad histopathology, the hormone levels and the transcriptional profiles of genes in the hypothalamic-pituitary-gonadal (HPG) axis in both sexes were examined. The results indicated that body weight was significantly reduced, the gonadal development was affected, and the levels of E
, T and 11-KT were remarkably disturbed in Cu-exposed fish. Moreover, the expression profiles of steroidogenesis-related genes in gonad (3βhsd, 17βhsd, cyp11a1, cyp17, cyp19a, lhr, fshr, hmgra and star) and in brains (ar, cyp19b, erα, er2β, lhβ, fshβ, gnrh2, gnrh3, gnrhr1, gnrh2 and gnrh4) displayed alterations after exposure to Cu. These results demonstrated that Cu could suppress the growth of zebrafish and significantly affect the reproductive biology in both sexes by damaging the structure of the gonads, altering the steroid hormone levels and the expressions of endocrine-related genes in HPG of zebrafish. This study suggests that Cu adversely affects the reproductive endocrine system in zebrafish and could pose a potential threat to fish populations inhabiting Cu-contaminated waters.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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