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31.
Polylactic acid (PLA) is a biodegradable and compostable polymer obtained from annually renewable resources and is acknowledged to be sustainable and non-polluting polymer with substantial commercial prospective as a textile fiber however, there is lack of literature on apparel applications of this polymer. Therefore in this study it was aimed to develop biobased compostable gloves from PLA draw textured melt spun yarns and to examine the effect of yarn linear density, fabric structure and stitch density on thermo-physiological comfort and moisture management properties of PLA based gloves. 100 % PLA based multifilament yarns of two different linear densities were melt spun and later draw textured on false twist texturing machine to be used for gloves knitting. Single jersey and rib structures were produced with two different stitch densities to investigate their effect on thermal conductivity, thermal resistance, relative water vapour permeability, air permeability and moisture management properties of the gloves. Minitab statistical software was employed to analyze the results of test samples. The coefficients of determinations (R2 values) presented good estimation capability of the established regression models. The outcomes of this research may be useful in determining suitable manufacturing requirements of PLA based gloves to accomplish precise thermo-physiological and moisture management properties. 相似文献
32.
Fuel accounts for more than 35% of transport costs in Swedish forestry, and reduced fuel consumption would provide immediate economic and environmental benefits. The objective of this study was to quantify the effect of road gradient, curvature and surface roughness on fuel consumption of a conventional 60-ton logging truck. The study used a 320-km test track on both public and forest roads. The track was driven with various load weights in both dry summer and wet autumn conditions. Fuel consumption data were retrieved from the truck's CAN-bus system, and road data were measured with a profilograph. Average fuel consumption was 71.4?litres/100?km. A regression analysis showed that the most important factor was the interaction between vehicle weight and gradient, explaining the 86% increase between empty and fully loaded truck. In addition, the regression analysis quantified the individual effects of undulation, curvature and surface roughness, explaining the 107% increase in fuel consumption between the highest and lowest road class. Results from the proposed regression model (R2 of 84% for a road section length of 1000?m) were consistent with predictions given by the European ARTEMIS model, and the proposed model can be used to improve cost estimation and route selection. 相似文献
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34.
Per Wallgren Inger Marit Brunborg Gunilla Blomqvist Gunnar Bergstr?m Frida Wikstr?m Gordon Allan Caroline Fossum Christine Monceyron Jonassen 《Acta veterinaria Scandinavica》2009,51(1):13
Background
Postweaning Multisystemic Wasting Syndrome (PMWS) is an emerging disease in pigs of multifactorial origin, but associated to porcine circovirus type 2 (PCV2) infection. PMWS was first diagnosed in Sweden at a progeny test station that received pigs aged five weeks from 19 different nucleus herds on the day after weaning. The objective of this study was to examine, for the first time in an index outbreak of PMWS, the relationship between PCV2 virus, antibodies to PCV2 and serum amyloid a (SAA) in sequentially collected serum samples from pigs with and without signs of PMWS.Methods
Forty pigs of the last batch that entered the station at a mean age of 37.5 days were monitored for signs of PMWS during the first 55 days after arrival. Serum was collected on six occasions and analysed for presence of PCV2 DNA and antibodies to PCV2, as well as for levels of SAA.Results
Four of the pigs (10%) were concluded to have developed PMWS, with necropsy confirmation in three of them. These pigs displayed low levels of maternal antibodies to PCV2, more than 107 PCV2 viral DNA copies per ml serum and failed to mount a serological response to the virus. Starting between day 23 and 34 after arrival, an increase in PCV2 viral load was seen in all pigs, but PCV2 did not induce any SAA-response. Pigs that remained healthy seroconverted to PCV2 as the viral load was increased, regardless of initially having low or high levels of PCV2-antibodies.Conclusion
In this index case of PMWS in Sweden, pigs affected by PMWS were not able to mount a relevant serum antibody response which contributed to the disease progression. The maximal PCV2 virus load was significantly higher and was also detected at an earlier stage in PMWS-affected pigs than in healthy pigs. However, a viral load above 107 PCV2 DNA copies per ml serum was also recorded in 18 out of 34 pigs without any clinical signs of PMWS, suggesting that these pigs were able to initiate a protective immune response to PCV2. 相似文献35.
Maria Christiernin Shannon M. Notley Liming Zhang Thomas Nilsson Gunnar Henriksson 《Wood Science and Technology》2009,43(1-2):23-41
Wood from white spruce Picea glauca that had been preserved by rapid burial in lake sediments 10,000 years ago, was investigated and compared to a contemporary reference white spruce wood. The 10,000-year old sample appeared to have an intact primary cell wall and middle lamella, whereas the carbohydrate monomer distribution, and microscopic images showed that the secondary wall was at least partially removed, indicating that this structure had been selectively attacked by bacteria. The Klason lignin amount in the aged spruce was found to be 60%. The relative lignin monomer content in the aged spruce was 9% lower than that of the reference wood, showing that there were fewer β-O-4′ linkages in the aged sample. This finding was supported by SEC analysis of the thioacidolysed samples as a larger proportion of lignin oligomers were observed in the aged spruce than in the reference material. This indicates a somewhat greater number of condensed bonds in the aged spruce than in the reference spruce sample. Quantitative 13C NMR analysis and HSQC techniques applied on milled wood lignins (MWL) revealed no significant structural differences between the aged spruce and the reference. 相似文献
36.
Nguyen D. Kien Tran H. Quang Gunnar Jansson Chris Harwood David Clapham Sara von Arnold 《Annals of Forest Science》2009,66(7):711-711
37.
Tran Ho Quang Nguyen Duc Kien Sara von Arnold Gunnar Jansson Ha Huy Thinh David Clapham 《New Forests》2010,39(3):301-312
Lignin and cellulose contents and wood basic density were related to diameter at breast height (DBH) in six fast-growing and
five slow-growing families from a combined progeny test and seedling seed orchard of Eucalyptus urophylla grown for 10 years in northern Vietnam. The mean cellulose content of the fast-growing families was significantly higher
than that of the slow growing-families (40.0 and 37.1%, respectively), and for individual trees cellulose content was significantly
correlated phenotypically with DBH. Wood basic density was significantly lower in the fast-growing group than in the slow-growing
group (0.506 and 0.535 g cm−3, respectively), and was significantly negatively correlated phenotypically with DBH. The lignin contents were not significantly
different between groups. Cellulose content and wood basic density were not correlated. The main conclusion is that there
is no obstacle to combining high growth rate with high cellulose content, for plantation of forests intended mainly for pulpwood. 相似文献
38.
Tungtrakanpoung R Pitaksajjakul P Na-Ngarm N Chaicumpa W Ekpo P Saengjaruk P Froman G Ramasoota P 《Veterinary microbiology》2006,115(1-3):54-63
The study aim was to use random heptapeptide library displayed by bacteriophage T7 for identifying mimotopes from 15 monoclonal antibodies (MAbs) specific to Leptospira spp., and from four leptospirosis patient sera, respectively. The bound phages, selected from fourth round of bio-panning with each antibody, were cloned by plaque isolation and the binding specificity of individual clones were confirmed by enzyme-linked immunosorbent assay, before being further amplified and checked for phage peptide sequence using PCR and DNA sequencing. All together 150 phages were selected, mimotope from 86 phages (56.6%) were found to match with protein sequences of Leptospira from GenBank database. The predominant mimotopes were mimotope with sequence LTPCD that found in 27.3%, followed by TPCSK (16%), KSKKSS (4%), KTKRXAS (4%), SSKSYR (3.3%), DPNXNSF (3.3%), KSGRC (2.6%), TLINIF (2%), TPCI (2%), 1.33% each with mimotopes PKKS, PCNTKXTA, and CTKKK, and one phage each (0.66%) with mimotopes PTFGS, TNSKRK, SKSSRC, RSKRIR, VTNNTP, and CSNXSKR. Interestingly, mimotopes LTPCD, TPCSK, and TPCI were found to react with both MAb and patient's sera. The matched proteins from GenBank namely, leptospiral putative outer membrane protein (matched with mimotope PTFGS), thermolysin precursor protein (matched with mimotope TPCIXXGSAS), and hypothetical protein LIC12228 (matched with mimotope CSNXSKR), were found to locate at outer membrane of Leptospira. These phage mimotopes and matched proteins may have potential for further use as diagnostic reagent and immunogen against leptospirosis in the future. The results demonstrate that phage display technique has potential for rapidly identifying phage mimotopes that interact with leptospiral MAbs and patient's sera. 相似文献
39.
Metz M Piliponsky AM Chen CC Lammel V Abrink M Pejler G Tsai M Galli SJ 《Science (New York, N.Y.)》2006,313(5786):526-530
Snake or honeybee envenomation can cause substantial morbidity and mortality, and it has been proposed that the activation of mast cells by snake or insect venoms can contribute to these effects. We show, in contrast, that mast cells can significantly reduce snake-venom-induced pathology in mice, at least in part by releasing carboxypeptidase A and possibly other proteases, which can degrade venom components. Mast cells also significantly reduced the morbidity and mortality induced by honeybee venom. These findings identify a new biological function for mast cells in enhancing resistance to the morbidity and mortality induced by animal venoms. 相似文献
40.
Teeling H Fuchs BM Becher D Klockow C Gardebrecht A Bennke CM Kassabgy M Huang S Mann AJ Waldmann J Weber M Klindworth A Otto A Lange J Bernhardt J Reinsch C Hecker M Peplies J Bockelmann FD Callies U Gerdts G Wichels A Wiltshire KH Glöckner FO Schweder T Amann R 《Science (New York, N.Y.)》2012,336(6081):608-611
Phytoplankton blooms characterize temperate ocean margin zones in spring. We investigated the bacterioplankton response to a diatom bloom in the North Sea and observed a dynamic succession of populations at genus-level resolution. Taxonomically distinct expressions of carbohydrate-active enzymes (transporters; in particular, TonB-dependent transporters) and phosphate acquisition strategies were found, indicating that distinct populations of Bacteroidetes, Gammaproteobacteria, and Alphaproteobacteria are specialized for successive decomposition of algal-derived organic matter. Our results suggest that algal substrate availability provided a series of ecological niches in which specialized populations could bloom. This reveals how planktonic species, despite their seemingly homogeneous habitat, can evade extinction by direct competition. 相似文献