19 research outputs found

    Prediction of Veneer Moisture Content Based on Near Infrared Spectroscopy

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    The physical properties of wood, particularly the dimensional stability, are affected by the water content. Most wood properties can be detected by near infrared spectroscopy (NIRS), which is used as a nondestructive testing method. At different wavelengths, different absorption peaks are presented with the moisture absorbed by wood. According to this feature, the absorption peaks can be collected, and the data can be processed by partial least squares method combined with NIRS. In this study, softwood oak and hardwood ash tree specimens were studied. In the infrared spectrum range, the wood moisture absorption curve was noticeable and the curve trend was similar, although the tree species were different. After centralization, standardization, and derivative processing of the spectral data, the correlation coefficients of oak and ash tree validations were high, reaching 0.9021 and 0.9661, respectively. The wood moisture content was predicted using NIRS and an algorithm. The experiments showed that this method is feasible

    Relationship between Tree Richness and Temporary Stability of Plant Communities: A Case Study of a Forest in Northeast China

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    The relationship between diversity and stability is a classic issue in ecology, but no general consensus has been achieved. To address this relationship, a field survey of a forest in Northeast China was conducted. The temporary stability was defined from the perspective of community characteristics. The results showed that communities with the highest temporary stability value were characterized by a single dominant species. A significant linear relationship with a low R2 value was observed between temporary stability and tree richness. When dominant and non-dominant tree species were studied, no significant linear relationship was obtained between temporary stability and non-dominant tree richness. However, the relationship between temporary stability and dominant tree richness was significant with a high R2 value, and the temporary stability decreased with increasing dominant tree richness. This study demonstrates that dominant tree richness is closely related to temporary stability, and temporary stability can serve as a stability indicator. The results provide a new perspective for understanding stability and additional information for revealing the relationship between diversity and stability in forest ecosystems

    Additional file 1: of Porous TiO2 Assembled from Monodispersed Nanoparticles

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    Supporting information. Figure S1. XRD patterns of TiO2-NPs. Figure S2. TEM image of TiO2-NPs. Figure S3. Size distribution histogram of TiO2-NPs. Figure S4. IR spectrum of the porous transparent bulk TiO2. Figure S5. TG analysis of the porous transparent bulk TiO2

    Resemblance of symptoms for major depression assessed at interview versus from hospital record review.

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    BACKGROUND: Diagnostic information for psychiatric research often depends on both clinical interviews and medical records. Although discrepancies between these two sources are well known, there have been few studies into the degree and origins of inconsistencies. PRINCIPAL FINDINGS: We compared data from structured interviews and medical records on 1,970 Han Chinese women with recurrent DSM-IV major depression (MD). Correlations were high for age at onset of MD (0.93) and number of episodes (0.70), intermediate for family history (+0.62) and duration of longest episode (+0.43) and variable but generally more modest for individual depressive symptoms (mean kappa = 0.32). Four factors were identified for twelve symptoms from medical records and the same four factors emerged from analysis of structured interviews. Factor congruencies were high but the correlation of factors between interviews and records were modest (i.e. +0.2 to +0.4). CONCLUSIONS: Structured interviews and medical records are highly concordant for age of onset, and the number and length of episodes, but agree more modestly for individual symptoms and symptom factors. The modesty of these correlations probably arises from multiple factors including i) inconsistency in the definition of the worst episode, ii) inaccuracies in self-report and iii) difficulties in coding medical records where symptoms were recorded solely for clinical purposes
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