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61.
One of the key challenges of distributed teams is the lack of social presence resulting from multiple work locations. Virtual environments (VEs) have been viewed as a collaboration tool for distributed teams that can enhance social presence via shared collaboration space and avatars. We observed, recorded, and analyzed the VE meetings of a globally distributed team. Data were analyzed through quantitative and qualitative content analysis. Our findings show that in the meetings, social presence was a situational phenomenon that constantly varied in strength. Social presence occurred as either a subgroup or group phenomenon, which at times coexisted at both levels. In particular, 2 of the 3 subdimensions of social presence, psychological involvement and behavioral engagement, were observable in team interaction. 相似文献
62.
Smriti Gurung Anu Gurung Chhatra M. Sharma Ingrid Jüttner Lekhendra Tripathee Roshan M. Bajracharya Nani Raut Preety Pradhananga Bishal K. Sitaula Yulan Zhang Shichang Kang Junming Guo 《Lakes & Reservoirs: Research and Management》2018,23(2):87-97
High altitude ecosystems have important natural ecological functions but are under increasing impacts from human activities and climate change. A detailed analysis of the water chemistry of Lake Rara, a high mountain lake in western Nepal, was carried out in October 2015 and April 2016. A total of 31 water samples were collected. Major ions (Ca2+, Mg2+, Na+, K+, SO42?, NO3? and Cl?) were analysed by ion chromatography. Si and PO43? were analysed following the standard protocols. Conductivity, pH, total dissolved solids (TDS), turbidity and dissolved oxygen (DO) were measured on‐site. The lake is oligotrophic characterized by low PO43? concentration (0.06 ± 0.01 mg/L), high DO values (6.73 ± 0.06 and 10.89 ± 0.86 mg/L), alkaline pH (8.42 ± 0.3 and 8.32 ± 0.23) and low conductivity (189.93 ± 5.3 and 189.22 ± 5.8 μS/cm). The concentrations of the major cations were in the order of Ca2+ > Mg2+ > K+ > Na+ (during both seasons), and for anions, it was HCO3? > SO42? > Cl? > NO3? and HCO3? > Cl? > NO3? > SO42? during postmonsoon and premonsoon, respectively. One‐way ANOVA revealed significant seasonal variations (p < 0.05) in most of the physicochemical parameters. The increased concentrations of most of the ions in the premonsoon time probably reflect long‐range transport of materials through dry deposition, whereas higher concentrations of NO3? and Cl? in some sites possibly reflect the localized impacts of settlement and grazing. The lake water was classified as Ca(Mg)HCO3. High (Ca2+ + Mg2+)/Tz+ ratio (0.97 in postmonsoon and 0.95 in premonsoon) and low (Na+ + K+)/Tz+ ratio (0.03 in postmonsoon and 0.04 in premonsoon) confirm carbonate weathering as the principal source of major ions with bedrock geology governing the water chemistry. The findings of this study build on the baseline dataset for assessing future anthropogenic influence on the lake and subsequent development for future lake management strategies. 相似文献
63.
Sample preparation method considerations for integrated transcriptomic and proteomic analysis of tumors
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Anupama Rajan Bhat Manoj Kumar Gupta Priya Krithivasan Kunal Dhas Jayalakshmi Nair Ram Bhupal Reddy Holalugunda Vittalamurthy Sudheendra Sandip Chavan Harsha Vardhan Sujatha Darsi Lavanya Balakrishnan Shanmukh Katragadda Vikram Kekatpure Amritha Suresh Pramila Tata Binay Panda Moni A. Kuriakose Ravi Sirdeshmukh 《Proteomics. Clinical applications》2017,11(3-4)
64.
Anu Mishra 《应用聚合物科学杂志》1982,27(2):381-395
Various poly(1-olefin)s have been studied as homoelectrets and their stabilities under different environmental conditions have been determined. It has been found that the stabilities of the homoelectrets, prepared from these polymers, depend on their volume resistivities, degrees of crystallinity, and the temperatures at which the crystalline domains of these polymers undergo transitional motions. Excellent stabilities have been exhibited by the homoelectrets prepared from poly(3-methyl-1-butene), poly(4-methyl-1-pentene) and other similar isotactic poly(1-olefin)s with pendant branched side chains. It is postulated that the charged particles are trapped at the crystalline/amorphous interfaces in these polymers and the bulky alkyl substituents stabilize the charged particles by raising the transition temperatures of these polymers as well as by providing some additional chemical interaction sites. 相似文献
65.
To clarify the mechanisms of antioxidant action, the effect of α-tocopherol and its water-soluble carboxylic acid derivative,
Trolox, was studied on the decomposition of methyl linoleate hydroperoxides (MeLoOOH). Decomposition rate and the distribution
of autoxidation products formed from MeLoOOH were followed by analyzing the volatile and nonvolatile products by static headspace
gas chromatography and normal-phase high-performance liquid chromatography, respectively. Both α-tocopherol and Trolox markedly
inhibited the decomposition of MeLoOOH in a concentration-dependent way. In the absence of antioxidants, MeLoOOH was completely
decomposed after incubation for 48 h at 60°C, and in the presence of equal molar concentration of antioxidants only 6–7% of
initial MeLoOOH was decomposed even after 280 h of incubation. MeLoOOH produced 1.2% methyl linoleate hydroxy compounds (MeLoOH)
in the presence of α-tocopherol and 3.8% in the presence of Trolox. Both antioxidants inhibited the formation of volatile
decomposition products and the formation of ketodiene compounds. The hydroxy compounds may be formed by the reaction of alkoxy
radical and hydrogen donating antioxidants. Conversion of MeLoOOH into stable MeLoOH demonstrated that the antioxidants α-tocopherol
and Trolox trap alkoxyl radicals by H-donation. 相似文献
66.
The initial steps in the autoxidation of CLA methyl ester are poorly understood. The aim of this study was to determine the
stereochemistry of the hydroperoxides formed during autoxidation of CLA methyl ester in the presence of a good hydrogen atom
donor. For this purpose, 9-cis, 11-trans CLA methyl ester was autoxidized in the presence of α-tocopherol under atmospheric oxygen at 40°C in the dark. The CLA methyl
ester hydroperoxides were isolated, reduced to the corresponding hydroxy derivatives, and separated by HPLC. The stereochemistry
of seven hydroxy-CLA methyl esters was investigated. The position of the hydroxy group was determined by GC-MS. The geometry
as well as the position of the double bonds in the alkyl chain was determined by NMR. In addition, the 13C NMR spectra of six hydroxy-CLA methyl esters were assigned using COSY, gradient heteronuclear multiple bond correlation,
gradient heteronuclear single quantum correlation, and total correlation spectroscopy experiments. The autoxidation of 9-cis, 11-trans CLA methyl ester in the presence of a good hydrogen atom donor is stereoselective in favor of one geometric isomer, namely
the 13-(R,S)-hydroperoxy-9-cis, 11-trans-octadecadienoic acid methyl ester. Three types of conjugated diene hydroperoxides are formed as primary hydroperoxides: trans,trans hydroperoxides (12-OOH-8t,10t and 9-OOH-10t,12t), a cis,trans hydroperoxide with the trans double bond adjacent to the hydroperoxide-bearing carbon atom (13-OOH-9c,11t), and a new type of cis,trans lipid hydroperoxide with the cis double bond adjacent to the hydroperoxide-bearing carbon atom (8-OOH-9c,11t). In addition, three nonkinetic hydroperoxides (13-OOH-9t,11t, 8-OOH-9t,11t, and 9-OOH-10t,12c) are formed. This study supports the theory that CLA methyl ester autoxidizes at least partly through an autocatalytic free
radical reaction. The complexity of the hydroperoxide mixture is due to formation of two different pentadienyl radicals. Moreover,
the stereoslectivity in favor of one geometric isomer can be explained by the selectivity of the two previous steps: the preferential
formation of a W-conformer of the pentadienyl radical over the Z-conformer, and regioselectivity of the oxygen addition to
the pentadienyl radical. 相似文献
67.
Anu M. Turpeinen Georg Alfthan Liisa Valsta Eino Hietanen Jukka T. Salonen Hanna Schunk Kristiina Nyyssönen Marja Mutanen 《Lipids》1995,30(6):485-492
The effects of natural mixed diets on lipid peroxidation were investigated in humans. In the first study, 59 subjects were
fed a rapeseed oil-based diet rich in monounsaturated fatty acids (MUFA) and a sunflower oil-based diet rich in polyunsaturated
fatty acids (PUFA) in a cross-over manner for three and a half weeks. The lipid peroxidation products in plasma were determined
by measuring conjugated dienes and malondialdehyde (MDA). In a second study, plasma thiobarbituric acid reactive substances
(TBARS), lipid hydroperoxides, and the susceptibility of very low density lipoprotein + low-density lipoprotein (LDL) toin vitro oxidation were measured from subjects fed similar MUFA and PUFA diets for six week diets. No significant differences in plasma
MDA or conjugated diene concentrations were found after the rapeseed oil diet or the sunflower oil diet in Study 1. In the
second study, a small but significant decrease (P<0.05) in both lipid hydroperoxides and TBARS was observed in the LDL fraction after the sunflower oil diet. Thein vitro oxidation gave opposite results, showing increased oxidation after the sunflower oil diet. Despite a high intake of α-tocopherol
during the oil peroids, no increase in plasma α-tocopherol was noticed in either study. The results suggest that moderate
changes in the fatty acid composition in the Western-type diet may be adequate to affect lipoprotein susceptibility to oxidationin vitro, but there is considerable disparity with some indices ofin vivo lipid peroxidation. 相似文献
68.
Blending of nylon-6 and nylon-66 was carried out by coextrusion in the whole range of compositions with particular emphasis on small amounts of one polymer in the other. Most significant improvement in properties is achieved at low blend compositions in which the minor component remains amorphous while severely affecting the crystallization behavior of the major component. The nylon-6-rich blends crystallize predominantly in the γ-crystalline form, whereas the nylon-66-rich blends exhibit low crystallinity. Because of this property, the blends are more easily drawable, giving rise to a more highly oriented structure with improved tensile properties and uniformity. High tenacity and modulus are observed in drawn blends containing 70% nylon 6 and 30% nylon-66. 相似文献
69.
Miina Rautiainen Matti Mõttus Anu Akujärvi Titta Majasalmi 《Remote sensing of environment》2011,115(12):3020-3028
The influence of the seasonal cycle of boreal forest understory has been noticed in global remote sensing of vegetation, especially in remote sensing of biophysical properties (e.g. leaf area index) of the tree-layer in a forest. A general problem in the validation of operationally produced global biophysical vegetation products is the lack of ground reference data on the seasonal variability of different land surface types. Currently, little is known about the spectral properties of the understory layers of boreal forests, and even less is known about the seasonal dynamics of the spectra. In this paper, we report seasonal trajectories of understory reflectance spectra measured in a European boreal forest. Four study sites representing different forest fertility site types were selected from central Finland. The understory composition was recorded and its spectra measured with an ASD FieldSpec Hand-Held UV/VNIR Spectroradiometer ten times during the growing period (from May to September) in 2010. Our results show that the spectral differences between and within understory types are the largest at the peak of the growing season in early July whereas in the beginning and end of the growing season (i.e. early May and late September, respectively) the differences between the understory types are marginal. In general, the fertile sites had the brightest NIR spectra throughout the growing season whereas infertile types appeared darker in NIR. Our results also indicated that a mismatch in the seasonal development of understory and tree layers does not occur in boreal forests: the understory and tree layer vegetation develop at a similar pace in the spring (i.e. there are no or only few spring ephemerals present), and the forests with the strongest seasonal dynamics in tree canopy structure (LAI) have also the strongest dynamics in understory spectra. 相似文献
70.
An improvement in the existing weighted grey-edge (GE) framework for colour constancy is proposed. The acquired images are denoised by vector filtering and then, a two-step colour correction process is performed. In the first step, the GE method is used for estimating the global illuminant and perform the initial level of colour correction. The computed illuminant as well as the initial corrected image are used in the second step, which employs the weighted GE method to iteratively compute the final illuminant for obtaining the final colour corrected image. One hundred sixty-five standard test images from a publicly available colour constancy dataset were used to study the efficacy of the proposed algorithm. The results obtained indicate a significant improvement in the colour correction process as compared to the state-of-the-art colour constancy methods. The proposed algorithm reduced the mean angular error by approximately 67.85% compared to the existing weighted GE method. 相似文献