265 research outputs found

    Pulping and Papermaking of Non-Wood Fibers

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    In general, the main raw materials of pulp and papermaking industry can be classified into three categories: wood, non-wood, and non-plant (mainly wastepaper), of which non-wood fiber material is an important fiber source in the areas where forest resources are scarce. Nowadays, in the total pulp consumption of the world, the proportions of wood pulp, wastepaper pulp, and non-wood pulp are 63, 34, and 3%, respectively. The effective use of non-wood fiber resources, especially grasses, cereal straws, corn stalks, bamboo, and bagasse, would play a major role in optimizing papermaking raw materials. On the other hand, there are non-wood fibers such as flax, hemp, jute, kenaf, cotton, sisal, and abaca with properties as good as or much better than softwood materials

    Light-sensitive features of seed germination in the invasive species Ageratina adenophora (syn. Eupatorium adenophorum) in China

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    Ageratina adenophora (Crofton weed) is a noxious invasive plant in several countries and its germination features favor its invasiveness. The aim of this study was to characterize the light-sensitive seed germination of this weed. Two to five-fold higher germination was observed under light conditions than under dark conditions. Dormancy-breaking methods of low temperature pre-treatment, pre-soaking with KNO3 solution, polyethylene glycol, and salicylic acid did not influence germination under either light or dark conditions. Very low light (39 μmol·m-2·s-1, 25% light transmittance) tripled seed germination from 22.3 to 66.7%, when compared to no light. Germination under violet, blue and green glass papers was significantly lower than that under yellow, orange, and red ones. Significant correlations between red-light intensity, red/far-red ratio and germination indicated that these 2 types of light may be responsible for the germination differences. Experiments under narrow band filters also proved this; red light at 630 nm could induce germination, while far-red light 740 nm could prevent germination. Thus, red/far-red light was effective in the photoblastic germination of Crofton weed, while other treatments could not replace light during germination. This photoblastic germination could favor the fast colonization of this weed when the seeds in deep soil approach the surface.Keywords: Crofton weed, plant invasiveness, light quality, light quantity, red/far-red ratio, biological contro

    GeohashTile: Vector Geographic Data Display Method Based on Geohash

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    © 2020 MDPI AG. All rights reserved. In the development of geographic information-based applications for mobile devices, achieving better access speed and visual effects is the main research aim. In this paper, we propose a new geographic data display method based on Geohash, namely GeohashTile, to improve the performance of traditional geographic data display methods in data indexing, data compression, and the projection of different granularities. First, we use the Geohash encoding system to represent coordinates, as well as to partition and index large-scale geographic data. The data compression and tile encoding is accomplished by Geohash. Second, to realize a direct conversion between Geohash and screen-pixel coordinates, we adopt the relative position projection method. Finally, we improve the calculation and rendering efficiency by using the intermediate result caching method. To evaluate the GeohashTile method, we have implemented the client and the server of the GeohashTile system, which is also evaluated in a real-world environment. The results show that Geohash encoding can accurately represent latitude and longitude coordinates in vector maps, while the GeohashTile framework has obvious advantages when requesting data volume and average load time compared to the state-of-the-art GeoTile system

    Shelterbelt Poplar Forests Induced Soil Changes in Deep Soil Profiles and Climates Contributed Their Inter-site Variations in Dryland Regions, Northeastern China

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    The influence of shelterbelt afforestation on soils in different-depth profiles and possible interaction with climatic conditions is important for evaluating ecological effects of large-scale afforestation programs. In the Songnen Plain, northeastern China, 720 soil samples were collected from five different soil layers (0–20, 20–40, 40–60, 60–80, and 80–100 cm) in shelterbelt poplar forests and neighboring farmlands. Soil physiochemical properties [pH, electrical conductivity (EC), soil porosity, soil moisture and bulk density], soil carbon and nutrients [soil organic carbon (SOC), N, alkaline-hydrolyzed N, P, available P, K and available K], forest characteristics [tree height, diameter at breast height (DBH), and density], climatic conditions [mean annual temperature (MAT), mean annual precipitation (MAP), and aridity index (ARID)], and soil texture (percentage of silt, clay, and sand) were measured. We found that the effects of shelterbelt afforestation on bulk density, porosity, available K, and total P were observed up to 100 cm deep; while the changes in available K and P were several-fold higher in the 0–20 cm soil layer than that in deeper layers (p < 0.05). For other parameters (soil pH and EC), shelterbelt-influences were mainly observed in surface soils, e.g., EC was 14.7% lower in shelterbelt plantations than that in farmlands in the 0–20 cm layer, about 2.5–3.5-fold higher than 60–100 cm soil inclusion. For soil moisture, shelterbelt afforestation decreased soil water by 7.3–8.7% in deep soils (p < 0.05), while no significant change was in 0–20 cm soil. For SOC and N, no significant differences between shelterbelt and farmlands were found in all five-depth soil profiles. Large inter-site variations were found for all shelterbelt-induced soil changes (p < 0.05) except for total K in the 0–20 cm layer. MAT and silt content provided the greatest explanation powers for inter-site variations in shelterbelt-induced soil properties changes. However, in deeper soils, water (ARID and MAP) explained more of the variation than that in surface soils. Therefore, shelterbelt afforestation in northeastern China could affect aspects of soil properties down to 100 cm deep, with inter-site variations mainly controlled by climate and soil texture, and greater contribution from water characteristics in deeper soils

    Hydrogeochemical Characteristics of High As and High F Groundwater in Hangjinhouqi, Hetao Plain, China

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    AbstractHangjinhouqi is one of the most serious endemic arsenic and fluorosis areas in Hetao Plain, China. Groundwater samples (n=97) and two sediment cores issued from boreholes were collected to characterize the hydrogeochemistry of groundwater and sediment lithology of aquifers. Results showed that arsenic and fluoride content in groundwater range from 1 to 1093μg/L and from 0.30 to 6.01mg/L, respectively. The highest concentrations are mainly found in the flat areas of the Yin Mountains. As and F are not correlated, suggesting that their origin and/or geochemical processes leading to their release to groundwater are different. Between 15 and 45m of depth, both arsenic and fluoride are more easily released into groundwater. The external environment of high As and high F groundwater formation consisted of a lake-based geographical environment in a long term and closed geological structure, arid and semi-arid climatic conditions, as well as hydrogeological characteristics

    Association of Base Excision Repair Gene Polymorphisms with ESRD Risk in a Chinese Population

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    The base excision repair (BER) pathway, containing OGG1, MTH1 and MUTYH, is a major protector from oxidative DNA damage in humans, while 8-oxoguanine (8-OHdG), an index of DNA oxidation, is increased in maintenance hemodialysis (HD) patients. Four polymorphisms of BER genes, OGG1 c.977C > G (rs1052133), MTH1 c.247G > A (rs4866), MUTYH c.972G > C (rs3219489), and AluYb8MUTYH (rs10527342), were examined in 337 HD patients and 404 healthy controls. And the 8-OHdG levels in leukocyte DNA were examined in 116 HD patients. The distribution of MUTYH c.972 GG or AluYb8MUTYH differed between the two groups and was associated with a moderately increased risk for end-stage renal disease (ESRD) (P = 0.013 and 0.034, resp.). The average 8-OHdG/106 dG value was significantly higher in patients with the OGG1 c.977G, MUTYH c.972G or AluYb8MUTYH alleles (P < 0.001 via ANOVA). Further analysis showed that combination of MUTYH c.972GG with OGG1 c.977GG or AluYb8MUTYH increased both the risk for ESRD and leukocyte DNA 8-OHdG levels in HD patients. Our study showed that MUTYH c.972GG, AluYb8MUTYH, and combination of OGG1 c.977GG increased the risk for ESRD development in China and suggested that DNA oxidative damage might be involved in such process

    Quantitative DNA Methylation Analysis of DLGAP2 Gene Using Pyrosequencing in Schizophrenia With Tardive Dyskinesia: A Linear Mixed Model Approach

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    Tardive dyskinesia (TD) is a side effect of antipsychotic medications used to treat schizophrenia (SCZ) and other mental health disorders. No study has previously used pyrosequencing to quantify DNA methylation levels of the DLGAP2 gene; while the quantitative methylation levels among CpG sites within a gene may be correlated. To deal with the correlated measures among three CpG sites within the DLGAP2 gene, this study analyzed DNA methylation levels of the DLGAP2 gene using a linear mixed model (LMM) in a Chinese sample consisting of 35 SCZ patients with TD, 35 SCZ without TD (NTD) and 34 healthy controls (HCs) collected in Beijing, China. The initial analysis using the non-parametric Kruskal-Wallis test revealed that three groups (TD, NTD and HC) had significant differences in DNA methylation level for CpG site 2 (p = 0.0119). Furthermore, the average methylation levels among the three CpG sites showed strong correlations (all p values \u3c 0.0001). In addition, using the LMM, three groups had significant differences in methylation level (p = 0.0027); while TD, NTD and TD + NTD groups showed higher average methylation levels than the HC group (p = 0.0024, 0.0151, and 0.0007, respectively). In conclusion, the LMM can accommodate a covariance structure. The findings of this study provide first evidence of DNA methylation levels in DLGAP2 associated with SCZ with TD in Chinese population. However, TD just showed borderline significant differences to NTD in this study

    Association between Nine Types of TCM Constitution and Five Chronic Diseases: A Correspondence Analysis Based on a Sample of 2,660 Participants

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    Objective. The purpose of this study was to explore the association of nine types of Traditional Chinese Medicine (TCM) constitution with the five chronic diseases: hypertension, hyperlipidemia, diabetes mellitus, heart disease, and obesity. Methods. Chi-squared test was performed to investigate the distribution characteristics of TCM constitutions in the participants with the five chronic diseases in questionnaire. Correspondence analysis was used to explore the correlation between them. Results. A total of 2,660 participants (1,400 males; 1,260 females) were included in this study. The mean age was 52.54 ± 13.92. Of them, 600 were of gentleness type accounting for 22.56%. Proportions of gentleness type in the chronic diseases (16.00%~23.70%) were less than that in general population (32.14%). The gentleness type and yin-deficiency type were significantly correlated with hypertension and diabetes mellitus, qi-deficiency type was correlated with heart disease, phlegm-dampness type was associated with obesity, and dampness-heat type was correlated with hyperlipidemia. Conclusions. The correlations between TCM constitution types and the five chronic diseases were different. This may have a significant implication for TCM practice, and even the people with gentleness type should not be ignored in health management

    A preliminary analysis of the effect of the new rural cooperative medical scheme on inpatient care at a county hospital

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    BACKGROUND: China in 2009 committed to reach universal health coverage by promoting three forms of health insurance; NCMS for the rural population, UEBMI for formally employed urban residents and URBMI for other urban residents. NCMS has expanded to near universal coverage in rural China since launching in 2003. The objective of this study aimed to assess the effect of NCMS on inpatient care utilization from 2003 to 2012 at Longyou county hospital, Zhejiang province. METHODS: The research was conducted at Longyou county, Zhejiang province. All registered inpatient admissions from January 1, 2003, to June 30, 2012, were included in the study. The PLSQL Developer software was used to select the interesting variables in the hospital information database and saved in an Excel 2003 file. The interesting variables included the patients’ general information (name, gender, age, payment method), discharge diagnosis, length of hospital stay, and expenditure (total expenditure and out-of-pocket payment). Two common diseases (coronary arteriosclerotic disease and pneumonia) were selected as tracer conditions. RESULTS: 292,400 rural residents were enrolled in the Longyou county NCMS by 2011, 95.4% of the eligible population. A total of 145,744 inpatient admissions were registered from 1 January 2003 to 30 June 2012. The proportion of inpatients covered by NCMS increased from 30.3% in 2004 to 54.2% in 2012 while the proportion of inpatients covered by UEBMI increased from 7.7% in 2003 to 14.7% in 2012. The average expenditure for UEBMI insured inpatients was higher than the average for NCMS insured inpatients, although the gap was narrowing. The average length of hospital stay increased every year for all inpatients, but was higher for UEBMI inpatients than for NCMS insured inpatients. For both tracer conditions the results were similar to the above findings. CONCLUSIONS: NCMS has improved coverage height for its enrollees and resulted in increased cost of care per inpatient admission at the county hospital. However, wide differences persist between the two insurance systems in coverage height. Both systems are associated with increasing lengths of stay and rising cost per inpatient admission. We found that around 30% of inpatients were not covered by any of the two public health insurance systems, which calls for further studies
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