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21.
Monika Büscher 《Computer Supported Cooperative Work (CSCW)》2014,23(2):223-238
This article takes departure in Barbara Czarniawska’s discussion of ‘Nomadic Work as Life-Story Plot’. It contextualises her analysis of actors’ interpretations of nomadic work with a bi-focal review of the ambiguous realities of these phenomena. Firstly, an examination of key aspects of the socio-economic and political context of nomadic work in global neoliberal economies reveals precarious conditions that cloud romantic interpretations of nomadicity. Secondly, a review of studies of everyday practices of nomadic work shows how neoliberal, but also alternative futures are enacted through creative appropriation of collaborative technologies. One example is the work of digital ‘disaster deck’ volunteers and its potential for the mobilization of ‘rapid, highly localized assistance’ through closer collaboration between a distributed crowd, local communities, and official emergency responders (Starbird and Palen 2013). This and other examples suggest emergent new practices and politics of dwelling in mobility that are focused on sociality and collaboration, straddling virtual and physical commons. The twin critique developed in this response can augment narrative analysis to inform more integrated CSCW innovation that challenges the ‘brave new world of work’. 相似文献
22.
Chemical analysis of volatiles emitted by Pinus svlvestris after induction by insect oviposition 总被引:1,自引:0,他引:1
Gas chromatography – mass spectrometry analyses of the headspace volatiles of Scots pine (Pinus sylvestris) induced by egg deposition of the sawfly Diprion pini were conducted. The odor blend of systemically oviposition-induced pine twigs, attractive for the eulophid egg parasitoid Chrysonotomyia ruforum, was compared to volatiles released by damaged pine twigs (control) that are not attractive for the parasitoid. The mechanical damage inflicted to the control twigs mimicked the damage by a sawfly female prior to egg deposition. The odor blend released by oviposition-induced pine twigs consisted of numerous mono- and sesquiterpenes, which all were also present in the headspace of the artificially damaged control twigs. A quantitative comparison of the volatiles from oviposition-induced twigs and controls revealed that only the amounts of (E)--farnesene were significantly higher in the volatile blend of the oviposition-induced twigs. Volatiles from pine twigs treated with jasmonic acid (JA) also attract the egg parasitoid. No qualitative differences were detected when comparing the composition of the headspace of JA-treated pine twigs with the volatile blend of untreated control twigs. JA-treated pine twigs released significantly higher amounts of (E)--farnesene. However, the JA treatment induced a significant increase of the amount of further terpenoid components. The release of terpenoids by pine after wounding, egg deposition, and JA treatment is discussed with special respect to (E)--farnesene. 相似文献
23.
Atle Wibe Anna-Karin Borg-Karlson Monika Persson Torbjörn Norin Hanna Mustaparta 《Journal of chemical ecology》1998,24(2):273-287
The enantiomeric composition of seven monoterpene hydrocarbons in headspace volatiles of spruce sawdust and seedlings (Picea abies), pine seedlings (Pinus sylvestris), and branches of juniper (Juniperus communis) was determined by gas chromatographic separation on a -Cyclodextrin column. For the six monoterpenes, -pinene, camphene, -pinene, sabinene, limonene, and -phellandrene, both enantiomers were present, whereas for 3-carene only the (+)-configuration was found. The amount of each enantiomer varied considerably both in relation to total amount of all of them, and for the six pairs also in relation to the opposite enantiomer. One olfactory receptor neuron in the pine weevil (Hylobius abietis) showed a strong response to -pinene when stimulated with all four headspace materials via a GC equipped with a DB-WAX column. The same neuron was subsequently tested with repeated stimulations via the GC effluent containing the (+)- or (–)-enantiomer. A marked better response to (+)- than to (–)--pinene was elicited. Another olfactory receptor neuron that responded strongly to limonene when stimulated with the spruce volatiles was tested for enantiomers of limonene. This neuron responded more strongly to (–)- than to (+)-limonene, when stimulated alternately with each of the limonene enantiomers. Discrimination between enantiomers by plant olfactory receptor neurons suggests that the enantiomeric ratios of volatile compounds may be important in host location by the pine weevil. 相似文献
24.
Juskanič Dominik Mištinová Jana Poláková Hollý Samuel Sekerešová Monika Koleják Kamil Pátrovič Lukáš 《Magma (New York, N.Y.)》2022,35(1):45-52
Magnetic Resonance Materials in Physics, Biology and Medicine - Oncometabolite D-2-hydroxyglutarate (2HG) is pooled in isocitrate dehydrogenase (IDH)-mutant glioma cells. Detecting 2HG by MR... 相似文献
25.
Anna Medyńska Danuta Zwolińska Ryszard Grenda Monika Miklaszewska Maria Szczepańska Agnieszka Urzykowska Katarzyna Zachwieja Katarzyna Kiliś‐Pstrusińska 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(4):557-565
Introduction: The aim of this study was to analyze the selected psychosocial aspects of chronic kidney disease in children treated with hemodialysis (HD). Methods: The study included 25 children treated with HD aged 2 to 18 years and their parents. Data concerning the illness and socio‐demographic parameters was collected. We used the Paediatric Quality of Life Inventory (PedsQL) for patients and for their parents the PedsQL‐proxy version, General Health Questionnaire (GHQ‐12), Berlin Social Support Scales (BSSS), and the Caregivers Burden Scale (CBS) to evaluate health‐related quality of life (QoL) of HD children and their primary caregivers. Findings: In the PedsQL test, the QoL of HD children was lower than in healthy children. Children treated with HD assessed their QoL on the PedsQL questionnaire higher than the primary caregivers, on all subscales as well as an overall health‐related QoL. Scoring below 2 on the GHQ‐12 test was reported in 56% of mothers, which may indicate that psychological symptoms have intensified. There was no correlation between BSSS, CBS, and GHQ‐12. Discussion: The assessment of QoL in pediatric patients would allow for the earliest possible identification of their nonsomatic problems and irregularities. This could, consequently, contribute to improving QoL in both children with chronic kidney disease and their families. 相似文献
26.
Monika Lachmapure Priti Paralikar Manikandan Palanisamy Monica Alves Mahendra Rai 《IET nanobiotechnology / IET》2017,11(7):809
Mycotic keratitis is mainly responsible for vision loss caused by various fungi. Sometimes, proper treatment of such infection is not possible due to unavailability of effective antifungal agents and development of resistance of such fungi to antimycotic drugs. Hence, it is necessary to search for potential antifungal agents, which can effectively eradicate fungal infection of eyes. Nanoparticles‐based antifungal drugs overcome this problem by increasing permeability and properties of drug molecules. In the present study, silver nanoparticles were synthesised by using Helminthosporium sp. and Chaetomium sp. following sequential reduction technique. The synthesised silver nanoparticles were detected primarily by UV‐visible spectrophotometer showing absorption spectra at 424 and 433 nm, respectively. Nanoparticles tracking analysis confirmed the mean particle size of silver nanoparticles as 45 and 55 nm. The synthesised AgNPs showed significant antifungal activity against fungi causing mycotic keratitis, when used alone and in combination with ketoconazole and amphotericin B in the range of 30–70 microgram per millilitre of minimum inhibitory concentration. Thus, the synthesised AgNPs can be used to enhance the activities of ketoconazole and amphotericin B.Inspec keywords: silver, nanoparticles, nanomedicine, antibacterial activity, diseases, permeability, ultraviolet spectra, visible spectra, particle sizeOther keywords: biogenic silver nanoparticles, fungi, mycotitic keratitis, vision loss, infection, antifungal agents, antimycotic drugs, antifungal drugs, permeability, Helminthosporium sp, Chaetomium sp, sequential reduction technique, UV‐visible spectrophotometer, mean particle size, ketoconazole, amphotericin B, wavelength 424 nm, wavelength 433 nm, size 45 nm, size 55 nm, Ag 相似文献
27.
Maria Giretova Lubomir Medvecky Radoslava Stulajterova Tibor Sopcak Jaroslav Briancin Monika Tatarkova 《Journal of materials science. Materials in medicine》2016,27(12):181
Polyhydroxybutyrate/chitosan/calcium phosphate composites are interesting biomaterials for utilization in regenerative medicine and they may by applied in reconstruction of deeper subchondral defects. Insufficient informations were found in recent papers about the influence of lysozyme degradation of chitosan in calcium phosphate/chitosan based composites on in vitro cytotoxicity and proliferation activity of osteoblasts. The effect of enzymatic chitosan degradation on osteoblasts proliferation was studied on composite films in which the porosity of origin 3D scaffolds was eliminated and the surface texture was modified. The significantly enhanced proliferation activity with faster population growth of osteoblasts were found on enzymatically degraded biopolymer composite films with α-tricalcium phosphate and nanohydroxyapatite. No cytotoxicity of composite films prepared from lysozyme degraded scaffolds containing a large fraction of low molecular weight chitosans (LMWC), was revealed after 10 days of cultivation. Contrary to above in the higher cytotoxicity origin untreated nanohydroxyapatite films and porous composite scaffolds. The results showed that the synergistic effect of surface distribution, morphology of nanohydroxyapatite particles, microtopography and the presence of LMWC due to chitosan degradation in composite films were responsible for compensation of the cytotoxicity of nanohydroxyapatite composite films or porous composite scaffolds. 相似文献
28.
Lin Song Monika Rawolle Nuri Hohn Jochen S. Gutmann Henrich Frielinghaus Peter Müller‐Buschbaum 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(30)
For many applications, mesoporous titania nanostructures are exposed to water or need to be backfilled via infiltration with an aqueous solution, which can cause deformations of the nanostructure by capillary forces. In this work, the degree of deformation caused by water infiltration in two types of mesoporous, nanostructured titania films exposed to water vapor is compared. The different types of nanostructured titania films are prepared via a polymer template assisted sol–gel synthesis in conjunction with a polymer‐template removal at high‐temperatures under ambient conditions versus nitrogen atmosphere. Information about surface and inner morphology is extracted by scanning electron microscopy and grazing incidence small‐angle neutron scattering (GISANS) measurements, respectively. Furthermore, complementary information on thin film composition and porosity are probed via X‐ray reflectivity. The backfilling induced deformation of near surface structures and structures inside the mesoporous titania films is determined by GISANS before and after D2O infiltration. The respective atmosphere used for template removal influences the details of the titania nanostructure and strongly impacts the degree of water induced deformation. Drying of the films shows reversibility of the deformation. 相似文献
29.
Lei Xie Monika Leester-Schädel Gerhard Ziegmann Stephanus Büttgenbach 《Microsystem Technologies》2010,16(6):1009-1013
Micro injection molded polymeric parts coated with functional thin films/layers show off the promising applications in microsystems
area. But the unfavorable and unavoidable defect of weld line in micro injection molding part leads to detrimental mechanical
and surface properties. The possibility of the functional thin film for enhancing micro injection molded weld lines was investigated.
Two typical coating materials (aluminum and titanium) with various film thicknesses (400, 600, 800 nm) were deposited on one
side of the micro injection molded weld line tensile sample via physical vapor deposition (PVD) method. The coated micro weld
line samples were characterized by tensile tests. The results show that PVD films of aluminum and titanium can reinforce the
strength and stiffness of micro injection molded weld line, even at thin thickness levels. But when the film thickness is
increasing, the weaker adhesion between metallic films and polymers decreased the PVD films’ enhancing performance for micro
weld line mechanical properties due to the degradation of polymers related to longer time exposure under high temperature. 相似文献
30.
Nelsestuen GL Harvey SB Zhang Y Kasthuri RS Sinaiko AR Ely EW Bernard GR Homoncik M Jilma B 《Proteomics. Clinical applications》2008,2(2):158-166
Although numerous protein biomarkers have been correlated with advanced disease states, no new clinical assays have been developed. Goals often anticipate disease-specific protein changes that exceed values among healthy individuals, a property common to acute phase reactants. This review considers somewhat different approaches. It focuses on intact protein isoform ratios that present a biomarker without change in the total concentration of the protein. These will seldom be detected by peptide level analysis or by most antibody-based assays. For example, application of an inexpensive method to large sample groups resulted in observation of several polymorphisms, including the first structural polymorphism of apolipoprotein C1. Isoform distribution of this protein was altered and was eventually linked to increased obesity. Numerous other protein isoforms included C- and N-terminal proteolysis, changes of glycoisoform ratios and certain types of sulfhydryl oxidation. While many of these gave excellent statistical correlation with advanced disease, clinical utility was not apparent. More important may be that protein isoform ratios were very stable in each individual. Diagnosis by longitudinal analysis of the same individual might increase sensitivity of protein biomarkers by 20-fold or more. Protein changes that exceed the range of values found among healthy individuals may be uncommon. 相似文献