| 1. |
|
|
| 2. |
|
|
| 3. |
- Holmberg, Sara, 1967-
(författare)
-
Musculoskeletal Disorders among Farmers and Referents, with Special Reference to Occurence, Health Care Utilization and Etiological Factors : A Population-based Study
- 2004
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives. To study the prevalence of musculoskeletal symptoms among farmers as compared to rural referents and to evaluate the effects of physical work exposures, psychosocial factors, lifestyle and comorbidity.Material and methods. A cross-sectional population-based survey of 1013 farmers and 769 matched referents was performed. Data on various symptoms, consultations and sick leave and information on primary health care and hospital admissions were obtained along with information on physical workload, psychosocial factors and lifestyle. Results. The farmers reported higher lifetime prevalence of symptoms from hands and forearms, low back and hips as compared to the referents. However, the farmers did not seek medical advice more often than the referents, and they reported significantly fewer sick leaves. After adjustment for the influence of physical work exposure, farmers still had a excess rate of low back pain (LBP) and hip symptoms as compared with the referents, while a lower rate of neck-shoulder symptoms was revealed. Several of the psychosocial variables were associated with LBP but the difference in LBP prevalence between farmers and referents could only be explained to some extent. LBP was associated with musculoskeletal symptoms other than LBP and with chest discomfort, dyspepsia, symptoms from mucous membranes, skin problems, work-related fever attacks, and primary care for digestive disorders. Presence of both respiratory and digestive disorders doubled the LBP prevalence.Conclusions. Symptoms from hips and low back were more frequent among farmers than among referents, but farmers did not seek more health care and reported fewer sick leaves than referents. Physical work exposure and psychosocial factors did not explain the differences in low back and hip symptoms between the two groups. Significant associations between LBP and digestive and respiratory disorders might indicate that these disorders may have etiological factors in common.
|
|
| 4. |
- Håkansson, Anders, et al.
(författare)
-
Romanfigurer ger liv åt tentans patientfall
- 2003
-
Ingår i: Läkartidningen. - 0023-7205. ; 100:43, s. 7-3425
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- I Lund avslutas läkarutbildningens tionde termin med en MEQ-skrivning (Modified Essay Questions). Höstterminen 2002 hämtade vi bakgrundsmiljö och persongalleri till frågornas fallbeskrivningar från ett skönlitterärt verk. Initiativet föll väl ut hos studenterna – de tyckte att boken var bra och att upplägget var utmärkt. Också författaren var nöjd – efter vår »medikalisering« lärde han känna sina romanfigurer på ett nytt och annorlunda sätt.
|
|
| 5. |
|
|
| 6. |
- Petersson, Karin, et al.
(författare)
-
Crystal structure of a superantigen bound to MHC class II displays zinc and peptide dependence
- 2001
-
Ingår i: EMBO Journal. - : Wiley. - 0261-4189 .- 1460-2075. ; 20:13, s. 3306-3312
-
Tidskriftsartikel (refereegranskat)abstract
- The three-dimensional structure of a bacterial superantigen, Staphylococcus aureus enterotoxin H (SEH), bound to human major histocompatibility complex (MHC) class II (HLA-DR1) has been determined by X-ray crystallography to 2.6 Å resolution (1HXY). The superantigen binds on top of HLA-DR1 in a completely different way from earlier co-crystallized superantigens from S. aureus. SEH interacts with high affinity through a zinc ion with the β1 chain of HLA-DR1 and also with the peptide presented by HLA-DR1. The structure suggests that all superantigens interacting with MHC class II in a zinc-dependent manner present the superantigen in a common way. This suggests a new model for ternary complex formation with the T-cell receptor (TCR), in which a contact between the TCR and the MHC class II is unlikely.
|
|
| 7. |
- Andrén, Linus, et al.
(författare)
-
Identification of Dynamic Properties of Boring Bar Vibrations in a Continuous Boring Operation
- 2004
-
Ingår i: Mechanical systems and signal processing. - : Academic Press. - 0888-3270 .- 1096-1216. ; 18:4, s. 869-901
-
Tidskriftsartikel (refereegranskat)abstract
- Vibrations in internal turning operations are usually a cumbersome part of the manufacturing process. This article focuses on the boring bar vibrations. Boring bar vibrations in alloyed steel, stainless steel and cast iron have been measured in both the cutting speed direction and the cutting depth direction with the aid of accelerometers. The dynamic response of a boring bar seem to be a time varying process that exhibits non-linear behaviour. The process is influenced by non-stationary parameters that are not under the control of the operator or experimenter. The vibrations are clearly dominated by the first resonance frequency in one of the two directions of the boring bar. The problem with force modulation in rotary machinery, which appears as side band terms in the spectrum, is also addressed. Furthermore, the resonance frequencies of the boring bar are correlated to an Euler-Bernoulli beam model.
|
|
| 8. |
- Andrén, Linus, et al.
(författare)
-
Identification of Motion of Cutting Tool Vibration in a Continuous Boring Operation : Correlation to structural Properties
- 2004
-
Ingår i: Mechanical systems and signal processing. - : Academic Press, UK. - 0888-3270 .- 1096-1216. ; 18:4, s. 903-27
-
Tidskriftsartikel (refereegranskat)abstract
- The internal turning operation has a history of being a cumbersome metal working process as vibration in boring operations is usually inevitable. In this article, the deflection shapes and/or mode shapes as well as the resonance frequencies of a boring bar have been put under scrutiny. Three methods have been used in order to investigate dynamic properties of a clamped boring bar: a theoretical Euler-Bernoulli beam model, an experimental modal analysis and an operating deflection shape analysis. \\ The results indicate a correlation between the shapes of the deflection shapes and/or mode shapes produced by the three different analysis methods. On the other hand, the orientation of the forced deflection shapes and/or mode shapes and the resonance frequencies demonstrates differences between the three methods. During continuous cutting, it is demonstrated that the bending motion of the first two resonance frequencies is to a large extent in the cutting speed direction.
|
|
| 9. |
|
|
| 10. |
- Brandt, Anders, et al.
(författare)
-
Cyclostationary Analysis of Boring Bar Vibrations
- 2004
-
Konferensbidrag (refereegranskat)abstract
- Internal turning or boring operation is a common metal working process that is usually associated with vibration problems. The vibration problems in internal turning considerably influence important factors such as surface quality, productivity, production costs, etc. In order to gain further understanding of the dynamic metal cutting process, an important early step is to thoroughly classify the vibrations. Boring bar vibrations have previously been proven to be nonstationary when analyzed with traditional methods. For vibrations originating in a combination of a rotating workpiece and random material inhomogeneities, it can be anticipated that the vibrations have cyclostationary properties. Methods for analysis of cyclostationary signals have rendered an increasing interest in the past decade, especially in the telecommunications field. However, very little has been published on the use of these methods in vibration applications. In this paper we show there is strong statistical evidence of cyclostationary behavior in vibrations on an operating boring bar. Methods for estimating the cyclic autocorrelation function and cyclic spectrum for sampled data are developed and results are compared. Some preliminary results from implementing these methods on operating boring bar vibrations are also presented.
|
|
