| 1. |
|
|
| 2. |
- Crowley, T.A., et al.
(författare)
-
Synthesis of metal and metal oxide nanowires and nanotube arrays within a mesoporous silica template
- 2003
-
Ingår i: Chemistry of Materials. - : American Chemical Society (ACS). - 0897-4756 .- 1520-5002. ; 15:18, s. 3518-3522
-
Tidskriftsartikel (refereegranskat)abstract
- Metallic nanowires of cobalt, copper, and iron oxide magnetite (Fe3O4) have been synthesized within the pores of mesoporous silica using a supercritical fluid inclusion technique. The mesoporous matrix provides a means of producing a high density of stable, hexagonally ordered arrays of highly crystalline nanowires. The formation of the metal and metal oxide nanowires within the silica mesopores was confirmed by transmission electron microscopy (TEM), N2 adsorption experiments, and powder X-ray diffraction (PXRD). The mechanism of nanowire formation within the mesopores appears to occur through the initial binding and coating of the pore walls with the metal atoms to form tubelike structures within the mesoporous template. The thickness of these tubes subsequently increases with further metal deposition until nanowires are formed. Additionally, the crystal structure of the cobalt nanowires formed within the mesoporous template can be readily changed by manipulating the density of the supercritical fluid phase.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Gunnbjornsdottir, M. I., et al.
(författare)
-
Obesity and nocturnal gastro-oesophageal reflux are related to onset of asthma and respiratory symptoms
- 2004
-
Ingår i: Eur Respir J. - : European Respiratory Society (ERS). ; 24:1
-
Tidskriftsartikel (refereegranskat)abstract
- Several studies have identified obesity as a risk factor for asthma in both children and adults. An increased prevalence of asthma in subjects with gastro-oesophageal reflux (GOR) and obstructive sleep apnoea syndrome has also been reported. The aim of this investigation was to study obesity, nocturnal GOR and snoring as independent risk factors for onset of asthma and respiratory symptoms in a Nordic population. In a 5-10 yr follow-up study of the European Community Respiratory Health Survey in Iceland, Norway, Denmark, Sweden and Estonia, a postal questionnaire was sent to previous respondents. A total of 16,191 participants responded to the questionnaire. Reported onset of asthma, wheeze and night-time symptoms as well as nocturnal GOR and habitual snoring increased in prevalence along with the increase in body mass index (BMI). After adjusting for nocturnal GOR, habitual snoring and other confounders, obesity (BMI >30) remained significantly related to the onset of asthma, wheeze and night-time symptoms. Nocturnal GOR was independently related to the onset of asthma and in addition, both nocturnal GOR and habitual snoring were independently related to onset of wheeze and night-time symptoms. This study adds evidence to an independent relationship between obesity, nocturnal gastro-oesophageal reflux and habitual snoring and the onset of asthma and respiratory symptoms in adults.
|
|
| 6. |
- Netterlid, E, et al.
(författare)
-
Persistent itching nodules after the fourth dose of diphtheria-tetanus toxoid vaccines without evidence of delayed hypersensitivity to aluminium
- 2004
-
Ingår i: Vaccine. - : Elsevier BV. - 1873-2518 .- 0264-410X. ; 22:27-28, s. 3698-3706
-
Tidskriftsartikel (refereegranskat)abstract
- Studies in Gothenburg, Sweden, reported an exceptionally high rate of persistent itching nodules at the site of injection of aluminium containing vaccines, usually with positive epicutaneous tests to aluminium. When a new booster diphtheria-tetanus vaccine was introduced we performed a prospective cluster randomised active surveillance in 25,232 10-year-olds. Parental reports 6 months after vaccination with Duplex(R) or diTeBooster(R) were collected for 22,365 (88%) pupils in 851 schools. We identified 3-6 children per 10,000 with a local itching nodule persisting for at least 2 months. There were no significant differences between the vaccine groups. Contact allergy to aluminium was not detected. The findings support the use of the vaccine presently available in the Swedish vaccination program. Continued surveillance of persistent itching nodules and aluminium contact allergy is, however, warranted for vaccines containing pertussis toxoid and aluminium. (C) 2004 Elsevier Ltd. All rights reserved.
|
|
| 7. |
|
|
| 8. |
- Pokropivny, A.V., et al.
(författare)
-
Study of Nanoscale Contacts with the Help of Combined TEM-AFM Technique and Theoretical MD-TM Calculations: In situ Transformations of Gold Nanowires
- 2004
-
Ingår i: Physics of low-Dimensional structures. - 0204-3467. ; 1-2, s. 83-90
-
Tidskriftsartikel (refereegranskat)abstract
- Nanoscale gold contacts were investigated both experimentally and theoretically. Simulations of in situ processes in a new combined TEM-AFM microscope were performed by molecular dynamics and theoretical mechanics methods. Atomistic transformations of gold nanometer-sized wires (nanowires) between Au-probe and Au-surface were studied in processes both of loading-unloading and in the normal, lateral, diagonal and zigzag directions of the probe motion. Molecular dynamics was used for studies of "adhesion avalanche", shear and strain deformations. Theoretical mechanics was used for studies of jump-to-contact and jump-off-contact phenomena. Reorientations from (100) to (111) planes with formation of extended zigzag, vacancy cavities, a double-neck creation and a slip along the (110) plane with formation of twins and steps were observed. Deformation mechanisms were shown to depend on schemes of motions and on the ratio between the relative velocity of the probe and surface motion and the velocity of the defect relaxation.
|
|
| 9. |
|
|
| 10. |
- Ekenman, I, et al.
(författare)
-
The role of biomechanical shoe orthoses in tibial stress fracture prevention
- 2002
-
Ingår i: The American journal of sports medicine. - : SAGE Publications. - 0363-5465 .- 1552-3365. ; 30:6, s. 866-870
-
Tidskriftsartikel (refereegranskat)abstract
- Biomechanical orthoses have been shown to lower stress fracture incidence in infantry recruits. However, these results may not be applicable to running athletes.HypothesisTraining in either running shoes or military boots with custom biomechanical shoe orthoses lessens tibial bone strains and strain rates during walking and running.Study DesignRandomized controlled laboratory study.MethodsIn vivo strain measurements were made in nine subjects to determine whether the use of biomechanical orthoses lowers tibial strains during both walking and running and whether such lowering depends on the type of shoe worn. Measurements were made during treadmill walking at 5 km/hr and then during serial 2-km treadmill runs at 13 km/hr with running shoes, with and without the orthoses, and during serial 1-km runs with army boots, with and without the orthoses.ResultsWhen soft or semirigid biomechanical orthoses were worn with boots, the tibial peak-to-peak strains were significantly lowered. Soft orthoses also significantly lowered the tension and compression strain rates when worn with boots. During running, semirigid orthoses significantly increased the compression and tension strain rates when worn with boots.ConclusionsThe use of biomechanical orthoses may be warranted for tibial stress fracture prevention during training in which boots are worn and that mostly involves walking, but they are not warranted for activities that primarily involve running or are performed in running shoes.
|
|
| 11. |
- Erts, D, et al.
(författare)
-
Instrumentation of STM and AFM combined with transmission electron microscope
- 2001
-
Ingår i: Applied Physics A. - : Springer Science and Business Media LLC. - 0947-8396 .- 1432-0630. ; 72:7, s. 71-74
-
Tidskriftsartikel (refereegranskat)abstract
- A scanning tunneling microscope (STM) combined with a transmission electron microscope (TEM) is a powerful tool for direct investigation of structures, electronic properties, and interactions at the atomic scale. Here, we report on two different designs of such TEM-STM as well as an extension with an atomic force microscope (TEM-AFM). In the first TEM-STM design, a stepper motor, combined with a one-dimensional inertial slider, was used to perform the coarse approach. The advantage of this design was the strong pulling force that enabled notched metallic wires to be broken inside the TEM, which lead to clean sample surfaces. A second design, with a three-dimensional inertial slider, allowed lateral motion inside the TEM, which simplified the adjustment of tip location on the sample. By replacing the STM tip with a standard AFM-cantilever chip, a new combination was demonstrated: TEM-AFM. Here the force was simply measured by direct TEM imaging of the motion of the AFM tip. Some experimental results are included to illustrate the capabilities of TEM-STM and TEM-AFM.
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
- Hoffman, C. D., et al.
(författare)
-
Exposure to ozone gases in pulp mills and the onset of rhinitis
- 2004
-
Ingår i: Scand J Work Environ Health. ; 30:6
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Rhinitis is a common upper respiratory disease influenced by both genetic and environmental factors. It is also accepted that allergic rhinitis may precede asthma, a disease with more serious consequences. The purpose of this study was to determine whether the risk of noninfectious rhinitis is increased after accidental gassings with ozone among bleachery workers in two pulp mills. METHODS: Bleachery workers (N=120) from two Swedish pulp mills using ozone as their bleaching agent were compared with control workers (N=80) not exposed to ozone in two adjacent paper mills. All of the participants were mailed a respiratory questionnaire that included items about asthma, noninfectious rhinitis, self-reported gassings, and smoking. Hazard ratios (HR) were calculated with proportional hazards regression models. RESULTS: The bleachery workers who reported gassings from ozone were found to be at increased risk of noninfectious rhinitis [HR 3.4, 95% confidence interval (95% CI) 1.3-8.7] when compared with control workers. Bleachery workers without self-reported ozone gassings were not at increased risk (HR 0.9, 95% CI 0.3-2.4). CONCLUSION: Acute exposure to high levels of ozone increases the risk of noninfectious rhinitis. This finding supports the view that peak exposures to irritants should be prevented in pulp mills.
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
|
|
| 22. |
|
|
| 23. |
- Olin, AC, et al.
(författare)
-
Increased nitric oxide in exhaled air after intake of a nitrate-rich meal.
- 2001
-
Ingår i: Respiratory medicine. - : Elsevier BV. - 0954-6111. ; 95:2, s. 153-8
-
Tidskriftsartikel (refereegranskat)abstract
- Exhaled and nasal NO (ENO, NNO) have been suggested as markers for inflammation in lower and upper respiratory tract respectively. It is still unknown how a number of factors, apart from airway inflammation, can influence NO levels. The aim of this study was to determine the effect of a nitrate-rich meal on ENO and NNO. Sixteen healthy subjects were observed during 1 week on normal diet before a nitrate-restricted diet was introduced in the next. On day 3 of the second week they were made to ingest a nitrate rich meal. ENO, NNO, plasma nitrate and plasma L-arginine were followed before the meal and afterwards for 3 h. ENO and NNO as well as plasma nitrate and plasma L-arginine were significantly elevated after the nitrate-rich meal. The median maximal increase of ENO and NNO was 47% and 13% respectively. We found a moderate but significant correlation between the rise in plasma nitrate and ENO (r(s)=0.57, P=0.027) but none between plasma nitrate and NNO (r(s)=-0.02, P=0.95). As nitrate in the diet seems to substantially influence the levels of ENO it is important either to restrict or register the intake of nitrate-rich food prior to measuring ENO.
|
|
| 24. |
|
|
| 25. |
|
|
