| 1. |
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| 2. |
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| 3. |
- Andersson, Martin, et al.
(författare)
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Effect of Assembly Errors in Back-to-Back Gear Efficiency Testing
- 2014
-
Ingår i: International Gear Conference 2014. - : Woodhead Publishing Limited. - 9781782421955 - 9781782421948 ; , s. 784-793
-
Konferensbidrag (refereegranskat)abstract
- As gear efficiency is improved in small steps, it is important to be able to distinguish actual improvements from scatter that can occur while testing. An FZG back-to-back gear test rig was used to investigate how the assembly and re-assembly of the same test setup affects the measurements. A spread in loss torque between one assembly and another of the same test setup were observed. Rig conditions also affected the spread in input torque. With knowledge of how the spread in loss torque varies due to assembly, test results could be distinguished between changes due to assembly and actual differences between tests.
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| 4. |
- Axelsson, Mette, et al.
(författare)
-
Mat vid diabetes. : En systematisk översikt med utvärdering av effekter samt hälsoekonomiska och etiska aspekter.
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- SlutsatserTyp 1- och typ 2-diabetes Det finns ett samband mellan att äta medelhavskost och lägre risk att dö i förtid oavsett orsak (måttlig tillförlitlighet). Det finns ett samband mellan att äta en större andel2 fibrer eller baljväxter och lägre risk att dö i förtid oavsett orsak (måttlig tillförlitlighet). Det kan även finnas ett samband mellan att äta en större andel nötter och lägre risk att dö i förtid oavsett orsak (låg tillförlitlighet) samt lägre risk att insjukna i hjärt- och kärlsjukdom (låg tillförlitlighet). Det finns ett samband mellan att dricka mer2 kaffe och lägre risk att dö i förtid oavsett orsak och lägre risk att dö i förtid i kranskärlssjukdom (måttlig tillförlitlighet) samt möjligen en lägre risk att dö i förtid i hjärt- och kärlsjukdom (låg tillförlitlighet). Det råder generell brist på studier med lång uppföljningstid som jämför inverkan av olika slags kostråd på överlevnad, diabeteskomplikationer, diabetesremission3, livskvalitet och biverkningar. Tillförlitligheten av befintliga resultat är dessutom mycket låg för de flesta koster, kostbehandlingar, livsmedel och näringsämnen som har utvärderats. Effekter på hälsa och relaterade mått kan i dessa fall inte bedömas.2. Begreppet ”större andel” eller ”mer” avser inte nödvändigtvis att äta eller dricka mer totalt utan att öka mängden av ett visst livsmedel genom att byta ut annan mat eller dryck.Typ 2-diabetes Det kan finnas ett samband mellan att äta en större andel mättat fett och högre risk för att dö i förtid av hjärt- och kärlsjukdom (låg tillförlitlighet). Det kan även finnas ett samband mellan att äta en större andel enkelomättat fett och lägre risk att dö i förtid oavsett orsak (låg tillförlitlighet). En behandling med en initial period av kraftigt minskat energiintag med hjälp av lågenergipulver (VLED) med efterföljande övergång till mat för viktstabilitet jämfört med vanlig kostbehandling har gynnsamma effekter på livskvalitet (enligt EQ-5D), långtidsblodsocker (HbA1c) och vikt upp till 12 månader (måttlig tillförlitlighet)4. Vidare kan metoder där VLED ingår ha gynnsamma effekter på diabetesremission5 och midjeomfång upp till 12 månader (låg tillförlitlighet) och långtidsblodsocker (HbA1c) upp till 24 månader (låg tillförlitlighet). Intensiv livsstilsbehandling därlågfettkost kombineras med fysisk aktivitet och minskat energiintag har gynnsamma effekter jämfört med vanlig kostbehandling på långtidsblodsocker (HbA1c), vikt, kroppsmasseindex (BMI), midjeomfång och vissa blodfetter upp till 12 månader (måttlig tillförlitlighet)3. Viktminskningen kan kvarstå upp till omkring 10 år (låg tillförlitlighet). Behandlingen kan leda till bättre fysisk livskvalitet upp till 8 år (låg tillförlitlighet) medan effektskillnaden i psykisk livskvalitet under samma tid kan vara obefintlig eller försumbar (låg tillförlitlighet). Jämförelsen påvisar ingen förändrad risk att dö i förtid oavsett orsak eller att dö eller insjukna av kardiovaskulära orsaker efter omkring 10 år (låg tillförlitlighet). I det hälsoekonomiska perspektivet är intensiv livsstilsbehandling mer resurskrävande än vanlig kostbehandling, och beräkningar visar små eller inga vinster i kvalitetsjusterade levnadsår (QALYs) på individnivå. Energirestriktion i samband med intensiv livsstilsbehandling med ketogen kost eller med högproteinkost (20 E%) i kombination med fysisk aktivitet jämfört med vanlig kostbehandling kan ge en viktminskning upp till 11 månader (låg tillförlitlighet) men det saknas studier som kan visa om vikten kan bibehållas på längre sikt. Det saknas studier som undersökt kliniskt viktiga utfall som dödlighet, kardiovaskulära sjukdomar, livskvalitet och diabetesremission.3. Gäller endast vid typ 2-diabetes.4. Utgår från individer med en medelkroppsvikt på cirka 100 kg och medel-HbA1c på 60 mmol/mol.5. Resultaten för utfallet diabetesremission (att uppnå normala blodsockervärden) gäller när en diabetesdiagnos sattes för mindre än 6 år sedan eller för mindre än 3 år sedan. Definitionen för diabetesremission var ett HbA1c på mindre än 48 mmol/mol och att samtidigt vara fri från blodsockersänkande läkemedel.Graviditetsdiabetes Det saknas studier om kost vid graviditetsdiabetes med tillräcklig tillförlitlighet för att kunna bedöma effekterna.
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| 5. |
- Brandström, Per, 1959, et al.
(författare)
-
The Swedish Reflux Trial in Children: I. Study Design and Study Population Characteristics
- 2010
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Ingår i: Journal of Urology. - : Ovid Technologies (Wolters Kluwer Health). - 0022-5347 .- 1527-3792. ; 184:1, s. 274-279
-
Konferensbidrag (refereegranskat)abstract
- Purpose: We compared the rates of febrile urinary tract infection, kidney damage and reflux resolution in children with vesicoureteral reflux treated in 3 ways, including antibiotic prophylaxis, endoscopic therapy and surveillance with antibiotics only for symptomatic urinary tract infection. Materials and Methods: Children 1 to younger than 2 years with grade reflux were recruited into this prospective, open, randomized, controlled, multi-center study and followed for 2 years after randomization. The main study end points were recurrent febrile urinary tract infection, renal status on dimercaptosuccinic acid scintigraphy and reflux status. Outcomes were analyzed by the intent to treat principle. Results: During a 6-year period 128 girls and 75 boys entered the study. In 96% of cases reflux was detected after urinary tract infection. The randomization procedure was successful and resulted in 3 groups matched for relevant factors. Recruitment was slower than anticipated but after patients were entered adherence to the protocol was good. Of the children 93% were followed for the intended 2 years without a treatment arm change. All except 2 patients completed 2-year followup scintigraphy. Conclusions: Recruitment was difficult but a substantial number of children were entered and randomly assigned to 3 groups with similar basic characteristics. Good adherence to the protocol made it possible to address the central study questions.
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| 6. |
- Cronberg, Carin, et al.
(författare)
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Peripheral arterial disease.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:1, s. 59-66
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Tidskriftsartikel (refereegranskat)
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| 7. |
- Devarakonda, Sravani, et al.
(författare)
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Low-grade intestinal inflammation two decades after pelvic radiotherapy.
- 2023
-
Ingår i: EBioMedicine. - 2352-3964. ; 94
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Tidskriftsartikel (refereegranskat)abstract
- Radiotherapy is effective in the treatment of cancer but also causes damage to non-cancerous tissue. Pelvic radiotherapy may produce chronic and debilitating bowel symptoms, yet the underlying pathophysiology is still undefined. Most notably, although pelvic radiotherapy causes an acute intestinal inflammation there is no consensus on whether the late-phase pathophysiology contains an inflammatory component or not. To address this knowledge gap, we examined the potential presence of a chronic inflammation in mucosal biopsies from irradiated pelvic cancer survivors.We biopsied 24 cancer survivors two to 20 years after pelvic radiotherapy, and four non-irradiated controls. Using tandem mass tag (TMT) mass spectrometry and mRNA sequencing (mRNA-seq), we charted proteomic and transcriptomic profiles of the mucosal tissue previously exposed to a high or a low/no dose of radiation. Changes in the immune cell populations were determined with flow cytometry. The integrity of the protective mucus layers were determined by permeability analysis and 16S rRNA bacterial detection.942 proteins were differentially expressed in mucosa previously exposed to a high radiation dose compared to a low radiation dose. The data suggested a chronic low-grade inflammation with neutrophil activity, which was confirmed by mRNA-seq and flow cytometry and further supported by findings of a weakened mucus barrier with bacterial infiltration.Our results challenge the idea that pelvic radiotherapy causes an acute intestinal inflammation that either heals or turns fibrotic without progression to chronic inflammation. This provides a rationale for exploring novel strategies to mitigate chronic bowel symptoms in pelvic cancer survivors.This study was supported by the King Gustav V Jubilee Clinic Cancer Foundation (CB), The Adlerbertska Research Foundation (CB), The Swedish Cancer Society (GS), The Swedish State under the ALF agreement (GS and CB), Mary von Sydow's foundation (MA and VP).
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| 8. |
- Fransen, Jian, et al.
(författare)
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Surveillance of antibiotic susceptibility in a Swedish Burn Center 1994-2012
- 2016
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Ingår i: Burns. - : Elsevier BV. - 0305-4179 .- 1879-1409. ; 42:6, s. 1295-1303
-
Tidskriftsartikel (refereegranskat)abstract
- Patients with burn trauma are at risk for infections caused by antibiotic resistant bacteria (ABR) with subsequent increase in morbidity and mortality. As part of the Swedish strategic program against antibiotic resistance in intensive care (ICU-Strama), we have surveyed the distribution of species and ABR in isolates from patients admitted to a Swedish burn center at Linkoping University Hospital from 1994 through 2012. In an international comparison Strama has been successful in reducing the antibiotic consumption among animals and humans in primary care. The aim of this study was to investigate the antibiotic consumption pressure and resistance rates in a Swedish burn unit. Methods: Microbiology data, total body surface area (TBSA), patient days, and mortality were collected from a hospital database for all patients admitted to the Burn Center at the University Hospital of Linkoping from April 1994 through December 2012. Results: A total of 1570 patients were admitted with a mean annual admission rate of 83 patients (range: 57-152). 15,006 microbiology cultures (approximately 10 per patient) were collected during the study period and of these 4531 were positive (approximately 3 per patient). The annual mean total body surface area (TBSA) was 13.4% (range 9.5-18.5) with an annual mortality rate of 5.4% (range 1-8%). The MRSA incidence was 1.7% (15/866) which corresponds to an MRSA incidence of 0.34/1000 admission days (TAD). Corresponding figures were for Escherichia coli resistant to 3rd generation cephalosporins (ESBL phenotype) 8% (13/170) and 0.3/TAD, Klebsiella spp. ESBL phenotype 5% (6/134) and 0.14/TAD, carbapenem resistant Pseudomonas aeruginosa 26% (56/209) and 1.28/TAD, and carbapenem resistant Acinetobacter spp. 3% (2/64) and 0.04/TAD. Conclusions: Our results show a sustained low risk for MRSA and high, although not increasing, risk for carbapenem resistant P. aeruginosa.
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| 9. |
- Gustafsson, Lars L., et al.
(författare)
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The 'wise list'- a comprehensive concept to select, communicate and achieve adherence to recommendations of essential drugs in ambulatory care in Stockholm
- 2011
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Ingår i: Basic & Clinical Pharmacology & Toxicology. - Copenhagen : Blackwell Publishing. - 1742-7835 .- 1742-7843. ; 108:4, s. 224-233
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to present and evaluate the impact of a comprehensive strategy over 10 years to select, communicate and achieve adherence to essential drug recommendations (EDR) in ambulatory care in a metropolitan healthcare region. EDRs were issued and launched as a 'Wise List' by the regional Drug and Therapeutics Committee in Stockholm. This study presents the concept by: (i) documenting the process for selecting, communicating and monitoring the impact of the 'Wise List'; (ii) analysing the variation in the number of drug substances recommended between 2000 and 2010; (iii) assessing the attitudes to the 'Wise List' among prescribers and the public; (iv) evaluating the adherence to recommendations between 2003 and 2009. The 'Wise List' consistently contained 200 drug substances for treating common diseases. The drugs were selected based on their efficacy, safety, suitability and cost-effectiveness. The 'Wise List' was known among one-third of a surveyed sample of the public in 2002 after initial marketing campaigns. All surveyed prescribers knew about the concept and 81% found the recommendations trustworthy in 2005. Adherence to recommendations increased from 69% in 1999 to 77% in 2009. In primary care, adherence increased from 83% to 87% from 2003 to 2009. The coefficient of variation (CV%) decreased from 6.1% to 3.8% for 156 healthcare centres between these years. The acceptance of the 'Wise List' in terms of trust among physicians and among the public and increased adherence may be explained by clear criteria for drug recommendations, a comprehensive communication strategy, electronic access to recommendations, continuous medical education and involvement of professional networks and patients.
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| 10. |
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| 11. |
- Hjelte, Jan, 1965-, et al.
(författare)
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From thought to action : young parents' reasons for participation in parenting support groups at child welfare centers
- 2015
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Ingår i: Social Work in Public Health. - Abingdon : Routledge. - 1937-1918 .- 1937-190X. ; 30:6, s. 516-533
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Tidskriftsartikel (refereegranskat)abstract
- In this article the focus is on young parents' engagement process in relation to participation in parenting support groups carried out at child welfare centers. This qualitative study focuses not only on young parents' reasons for participating or not participating in parenting support groups during different phases in their engagement process, but also on examining the circumstances that may contribute to such changes. The results show that these reasons can be divided into four categories: the staff, other participants, the social network, and practical circumstances. It also appears that these reasons change between different phases of their engagement process. Primarily three different circumstances contributed to variation in parents' reasons: difficulty in predicting the value of participation, increased closeness in relationships with staff and other parents, and the specific life phase in which young parents find themselves. The results have important implications for policy makers and practitioners in their work in formulating and updating parenting support; they also indicate what may be important to focus on in the recruitment of young parents, and also what may be crucial in regard to them completing their engagement in parent support groups.
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| 12. |
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| 13. |
- Hübbert, Laila
(författare)
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Between the Probe and the Pump : An experimental study on cardiac performance analysis based on Echocardiography, tissue and laser Doppler
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Echocardiography is an ultrasound-based bedside, non-invasive and easily available cardiac diagnostic technique visualising the heart’s morphology and function. Quantification of cardiac wall motion can be measured with the tissue Doppler Imaging (TDI) modality which provides in humans a high diagnostic capacity to differentiate healthy from diseased myocardium with reduced function. Heart failure, as a consequence of, for example, myocardial or ischaemic heart disease, demands both bedside and intraoperative diagnostic procedures for myocardial functional and perfusion assessment. In the late stages of heart failure cardiac left ventricular assist devices (LVAD) may be the treatment of choice. Such new technologies are commonly evaluated in large animals before application in humans is accepted.With the aim of evaluating TDI´s applicability and feasibility in a large animal model 21 calves (aged 3 months and weight around 70 kg), were studied with colour TDI (Paper I). Analysis was performed either during coronary artery occlusion when the laser Doppler perfusion imaging technique (LDMP) was refined (Paper II), or after implantation of the LVAD, Heart Mate II® (Papers III, IV). All animals were haemodynamically monitored (pressures, flows, heart rate) and ECG was continuously recorded. Transthoracic and epicardial echocardiography (TTE) were performed before and after sternotomy and intraoperatively during experimental progressive heart failure. Heart chamber dimensions, native stroke volume, systolic and diastolic regional basal myocardial peak velocities (cm/s; systolic S´, early diastolic E´, and atrial A´, strain (%), strain rate (s-1) and displacement (mm) were determined. Second harmonic imaging (SHI) was applied in order to better visualise air bubbles (Paper IV).In Paper I compiled baseline values were established before and after sternotomy for central haemodynamic and echocardiographic parameters, including the TDI myocardial motion variables velocity, strain rate, strain and displacement. Blood pressure and heart rate changed significantly after sternotomy, but the TDI derived data did not change significantly.In Paper II we report that movement artifacts of the laser Doppler myocardial perfusion measurements can be reduced, both when myocardium is normally perfused and during coronary occlusion, by using the TDI velocity registrations showing wall motion to be minimal. The optimum interval depends on the application but late systole as well as late diastole is preferred.After LVAD implantation in Paper III the flow characteristics and myocardial motion during variations in afterload TDI show that myocardial velocities decrease concomitantly with myocardial depression and are significantly correlated to native stroke volume, heart rate, systemic arterial resistance and cardiac output, but not with left ventricular size, fractional shortening or pump speed. Echocardiography together with TDI thereby offers additional means for monitoring and quantifying residual myocardial function during LVAD treatment.SHI is superior in the early detection of single air-bubbles in the ascending aorta prior to significant air embolism during manipulation of the LVAD pump speed, as shown in Paper IV. A prompt decrease in size of the left atrium during speed adjustment may be a warning that massive air embolism is imminent whereas the commonly used left atrial pressure not provide the same warning.
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| 14. |
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| 15. |
- Huss, Fredrik, 1971-, et al.
(författare)
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Buses as fire hazards : A Swedish problem only? Suggestions for fire-prevention measures
- 2004
-
Ingår i: Journal of Burn Care and Rehabilitation. - 0273-8481 .- 1534-5939. ; 25:4, s. 377-380
-
Tidskriftsartikel (refereegranskat)abstract
- In Sweden, approximately 6% of all human transportation is made via buses. The Swedish Board of Accident Investigation and the Swedish Rescue Services Agency have pointed out repeatedly that buses are potential fire and burn hazards, not only when involved in collisions but also in other circumstances. The number of fire incidents is increasing, especially in newer buses. In conjunction with the Swedish Rescue Services Agency, we examined some of the recent bus fires in Sweden. We did not find any casualties, but the results of our study suggest that casualties as a result of bus fires are imminent unless preventive measures are taken. We also studied experiences from previous bus fires and suggest preventive measures.
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| 16. |
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| 17. |
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| 18. |
- Huss, Fredrik, et al.
(författare)
-
[Lightning injuries--a mixture of electrical, thermal and multiple trauma].
- 2004
-
Ingår i: Läkartidningen. - 0023-7205 .- 1652-7518. ; 101:28-29, s. 2328-31
-
Tidskriftsartikel (refereegranskat)abstract
- There are several misconceptions even among hospital personnel regarding damages and injuries caused by lightning. Few health care providers have experience from lightning injuries as they are rare and different (DC) from the more common high-voltage (AC) injuries. Furthermore, fatalities are uncommon. Burns do occur but are usually minor. Most lightning injuries occur in the summer season during outdoor leisure activities and in the vicinity of a tree or other large structures. In Sweden, on average, approximately seventeen persons per year are hospitalised and 0.2-0.8 persons per million inhabitants and year die due to lightning injuries. The primary treatment follows the general guidelines for other trauma, electrical, and burn injuries, i.e. as is described in the standardised ATLS, ABLS, or A-HLR programmes. However, there are some minor points that are different and may be stressed for a favourable outcome. In this paper these are addressed together with the epidemiology, effects and treatment of lightning injuries that are specific for Sweden. Unfortunately, little is known, apart from what is described in smaller case series, of the long time sequelae experienced by this patient population and further research is therefore particularly warranted in this respect.
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| 19. |
- Jonsson, Ulf, 1960-, et al.
(författare)
-
Inledning
- 2009
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Ingår i: Kritiska tänkanden i religionsvetenskapen. - Nora : Bokförlaget Nya Doxa. - 9789157805430 ; , s. 7-18
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 20. |
- Jonsson, Ulf, 1960-, et al.
(författare)
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Kritiska tänkanden i religionsvetenskapen
- 2009
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- Religionens roll i samhället debatteras livligt i medier na och den radikala religionskritiken har vaknat till liv igen. Allt oftare påminns vi om religionernas irrationella sidor, vilket gör den högröstade kritiken begriplig. Författarna försöker förankra diskussionen i en nyanserad konstruktiv religionsvetenskaplig forskning.
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| 21. |
- Kurtser, Polina, 1990-, et al.
(författare)
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Development of novel robotic platforms for mechanical stress induction, and their effects on plant morphology, elements, and metabolism
- 2021
-
Ingår i: Scientific Reports. - : Springer Nature. - 2045-2322. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- This research evaluates the effect on herbal crops of mechanical stress induced by two specially developed robotic platforms. The changes in plant morphology, metabolite profiles, and element content are evaluated in a series of three empirical experiments, conducted in greenhouse and CNC growing bed conditions, for the case of basil plant growth. Results show significant changes in morphological features, including shortening of overall stem length by up to 40% and inter-node distances by up to 80%, for plants treated with a robotic mechanical stress-induction protocol, compared to control groups. Treated plants showed a significant increase in element absorption, by 20-250% compared to controls, and changes in the metabolite profiles suggested an improvement in plants' nutritional profiles. These results suggest that repetitive, robotic, mechanical stimuli could be potentially beneficial for plants' nutritional and taste properties, and could be performed with no human intervention (and therefore labor cost). The changes in morphological aspects of the plant could potentially replace practices involving chemical treatment of the plants, leading to more sustainable crop production.
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| 22. |
- Lidström, Kristoffer, 1981-, et al.
(författare)
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A Modular CACC System Integration Design
- 2012
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Ingår i: IEEE transactions on intelligent transportation systems (Print). - Piscataway : IEEE Press. - 1524-9050 .- 1558-0016. ; 13:3, s. 1050-
-
Tidskriftsartikel (refereegranskat)abstract
- This paper describes the Halmstad University entry in the GrCooperative Driving Challenge, which is a competition in vehicle platooning. Cooperative platooning has the potential to improve traffic flow by mitigating shock wave effects, which otherwise may occur in dense traffic. A longitudinal controller that uses information exchanged via wireless communication with other cooperative vehicles to achieve string-stable platooning is developed. The controller is integrated into a production vehicle, together with a positioning system, communication system, human€“machine interface (HMI). A highly modular system architecture enabled rapid development testing of the various subsystems. In the competition, which took place in May 2011 on a closed-off highway in The Netherlands, the Halmstad University team finished second among nine competing teams._x000D_
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| 23. |
- Lindahl, Göran, et al.
(författare)
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Bergslagen : Arbetsplatser och bostäder under hundra år
- 1983
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Rapport (populärvet., debatt m.m.)abstract
- Denna skrift utgör resultatet av Arkitekturskolans studier läsåret 1978-79. Att redigera manuskripten visade sig arbetskrävande och har också dragit ut på tiden. Att vissa av de uppgifter som lämnas inte är helt aktuella spelar ändå inte så stor roll - tyngdpunkten i framställningen ligger på det historiska materialet och de långa tidsperspektiven.Arbetet inleds med en demografisk översikt över ett brett bälte tvärs över Mellansverige från Värmland till Upplandskusten. Där antyds utvecklingens huvudriktning både i Bergslagens gamla kärnområden och i yttre zoner av delvis annan karaktär. Därefter följer åtta från varandra fristående kapitel som dock alla har ett gemensamt mål, att granska och analysera bebyggelseu.tvecklingen inom ett tydligt avgränsat område. Konkretion och åskådlighet har eftersträvats - därför har också stor möda nedlagts på bildmaterialet i form av kartor, ritningar och foton. Valet av undersökningsobjekt har gjorts av författarna själva, som också utformat sina avsnitt självständigt.
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| 24. |
- Lius, Andreas, 1990-, et al.
(författare)
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Experimental and chemical-kinetic evaluation of a heavy-duty methanol PFI engine with direct water injection
- 2024
-
Ingår i: Fuel. - : Elsevier Ltd. - 0016-2361 .- 1873-7153. ; 359
-
Tidskriftsartikel (refereegranskat)abstract
- Internal combustion engines are still widely used for propulsion in modern vehicles. Upcoming emission legislation imposes stricter limits on exhaust emissions. One method to achieve emission compliance is by using a three-way catalyst (TWC), which offers excellent emission reduction if the mixture is stoichiometric. However, stoichiometric mixtures in spark-ignited engines have the drawback of increased knock propensity. Knock can be mitigated by using water injection, which serves as both a diluent and utilizes latent heat to reduce the temperature, thereby reducing the reactivity of the unburned mixture. Methanol as a fuel has received more attention thanks to its high research octane number (RON) and its potential to contribute to decarbonization when produced as e- or bio-methanol. In the current study, Direct Water Injection (DWI) was evaluated on a Heavy-Duty (HD) single-cylinder research engine fueled by methanol. This work aims to fill a research gap on methanol-fueled engines with water injection. A direct injection system of water was chosen as it offers the freedom to inject during the closed cycle. Furthermore, a chemical kinetic study on the oxidation of stoichiometric methanol–water mixtures was conducted based on findings in the literature suggesting that, under certain conditions, water mixed with alcohol (in this case, ethanol) can reduce the ignition delay. The experimental results demonstrate that DWI effectively suppresses knock and reduced Nitrogen Oxides (NOx), albeit with deteriorated combustion efficiency. The chemical kinetic study suggested that at lower to intermediate temperatures, water acts as an efficient third-body collider, which lowers the ignition delay. However, this effect is not significant for the typical timescales encountered in HD engines.
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| 25. |
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| 26. |
- Maunsbach, Ulf, et al.
(författare)
-
Gränslös varumärkesanvändning
- 2006
-
Ingår i: Festskrift till Peter Seipel. - 9139011402
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 27. |
- Sillén, Ulla, 1946, et al.
(författare)
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The Swedish Reflux Trial in Children: V. Bladder Dysfunction.
- 2010
-
Ingår i: The Journal of urology. - : Ovid Technologies (Wolters Kluwer Health). - 1527-3792 .- 0022-5347. ; 184:1, s. 298-304
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: We investigated the prevalence and types of lower urinary tract dysfunction in children with vesicoureteral reflux grades III and IV, and related improved dilating reflux, renal damage and recurrent urinary tract infection to dysfunction. MATERIALS AND METHODS: A total of 203 children between ages 1 to less than 2 years with reflux grades III and IV were recruited into this open, randomized, controlled, multicenter study. Voiding cystourethrography and dimercapto-succinic acid scintigraphy were done at study entry and 2-year followup. Lower urinary tract function was investigated by noninvasive methods, at study entry with 4-hour voiding observation in 148 patients and at 2 years by structured questionnaire and post-void residual flow measurement in 161. RESULTS: At study entry 20% of patients had lower urinary tract dysfunction, characterized by high bladder capacity and increased post-void residual urine. At 2 years there was dysfunction in 34% of patients. Subdivision into groups characteristic of children after toilet training revealed that 9% had isolated overactive bladder and 24% had voiding phase dysfunction. There was a negative correlation between dysfunction at 2 years and improved dilating reflux (p = 0.002). Renal damage at study entry and followup was associated with lower urinary tract dysfunction at 2 years (p = 0.001). Recurrent urinary tract infections were seen in 33% of children with and in 20% without dysfunction (p = 0.084). CONCLUSIONS: After toilet training a third of these children with dilating reflux had lower urinary tract dysfunction, mainly voiding phase problems. Dysfunction was associated with persistent reflux and renal damage while dysfunction at study entry did not predict the 2-year outcome.
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| 28. |
- Sjöberg, Beatrice G., et al.
(författare)
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Low levels of IgM antibodies against phosphorylcholine : a potential risk marker for ischemic stroke in men
- 2009
-
Ingår i: Atherosclerosis. - : Elsevier BV. - 0021-9150 .- 1879-1484. ; 203:2, s. 528-532
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Natural antibodies specific for phosphorylcholine (anti-PC) have been implicated as protective factors in atherosclerosis. We herein determined the relationship between IgM anti-PC and incidence of cardiovascular disease (CVD). METHODS: We studied 349 incident cases (200 men) of first events of CVD (coronary heart disease (CHD; n=203 or ischemic stroke; n=146) and 693 age- and sex-matched controls identified through 12 years of follow-up (1991-2003) of subjects from the cardiovascular cohort within the Malmö Diet and Cancer Study. Relative risks (RR) of CVD with 95% confidence intervals (CI) of incident CVD with adjustments for age, smoking, total cholesterol and blood pressure were determined. Anti-PC-levels were measured using ELISA (Athera CVDefine). RESULTS: As determined using Athera CVDefine, significant associations were attained with values of anti-PC below 17U/ml (corresponding to the lowest 9th percentile), which remained after taking confounders into account (RR: 1.79, 95% CI: 1.09-2.94, p=0.021). If men were studied separately, significance was evident at values below 17U/ml (RR: 2.01, 95% CI: 1.11-3.67, p=0.022), which was not the case among women. Furthermore, values below 17U/ml were also associated with ischemic stroke (RR=3.67, 95% CI: 1.34-10.1, p=0.01), but not with CHD. CONCLUSION: Low IgM anti-PC could be a novel risk marker for development of ischemic stroke in men. Further studies are needed to establish gender and subgroup differences.
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| 30. |
- Sjöberg, Jonny, et al.
(författare)
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Computer simulations of blasting with precise initiation
- 2012
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Konferensbidrag (refereegranskat)abstract
- Using blasting caps with electronic delay units, it has become possible to employ wave superposition in rock blasting. This paper presents computer simulations to investigate the hypothesis that fragmentation is improved in areas between blast holes where the tensile waves meet, overlap and interact. In this study, a numerical methodology using the code LS-DYNA was developed. LS-DYNA is a commercially available multi-purpose finite-element code, which is well suited to various types of dynamic modeling. Two different element formulations were used — Euler formulation in, and close to, the blast hole, and Lagrange formulation in the rock volume farther from the blast hole. The models used have a resolution (element size) of 50 mm and comprise approximately 20 million elements. Single and dual blast hole configurations have been studied, and a methodology to calculate possible fragmentation based on model interpretation was developed. The results showed that the amount of explosives and the blast hole spacing had the largest effect on fragmentation. The effect of varying delay times was small and local, implying that a significant increase in fragmentation should not be expected through wave superposition.
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| 31. |
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| 32. |
- Sjöberg, Sören, et al.
(författare)
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Analysis of efficiency of spur ground gears and the influence of running-in
- 2016
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Ingår i: Tribology International. - : Elsevier. - 0301-679X .- 1879-2464. - 9781782421955 - 9781782421948 ; 93, s. 172-181
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Tidskriftsartikel (refereegranskat)abstract
- High-performing gear transmissions are needed to reduce CO2 emissions. In this paper an FZG gear test rig was used to investigate how two running-in loads affects the gear mesh efficiency for two different temperatures. The gear surface roughness was investigated in parallel with testing. Higher efficiency was observed for tests using a high running-in load, and for low lubricant temperatures. The running-in load had a larger effect on the mesh efficiency than temperature. The high running-in load also yielded higher gear mesh efficiency and had a larger impact on surface parameters.
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| 35. |
- Sjöberg, Sören, 1971-
(författare)
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Influence of running-in on gear efficiency
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The general trend in gear industry is an increased focus on gear transmission efficiency. This thesis focuses on the understanding of how different gear manufacturing methods – particularly the contribution of the running-in process – affect the surface characteristics and friction response, with the purpose of increasing gearbox efficiency. The thesis consists of a summary and five appended papers.The research hypothesis in paper A and paper B was that the dry elastic contact area ratio is a descriptive parameter for the contact condition. Paper A deals with the influence of manufacturing method on the initial contact conditions. The emphasis in paper B is the changes that occur during running-in and correlating these changes to design requirements. Paper C examines the influence of manganese phosphate coating and lubricants, with respect to friction and the risk of scuffing at the initial contact. Paper D examines the effect of running-in load on the friction response for different surfaces. In paper E, the question of whether the load during running-in influences the gear mesh efficiency is further expounded.The main conclusions of this thesis are that the running-in influences the gear mesh efficiency; a high running-in load enhances the gear mesh efficiency. The difference in mesh efficiency is in the range of one tenth of a per cent. Thus, the influence of running-in cannot be neglected because it is in the same order of magnitude as reported for other gear efficiency enhancements. Furthermore, the dry elastic contact area ratio presents a descriptive measure of how surface topography influences the contact, at both a global (form deviation) and local (roughness) level. The surface topography caused by the manufacturing method has a significant influence on the contact area ratio. Shaving was found to have the highest contact area ratio, and would therefore be the best choice if deviations from case hardening could be minimised. It was also confirmed that surfaces coated with manganese phosphate raise the limiting load for scuffing failure up to 13 times compared to the uncoated ground equivalent.
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| 36. |
- Sjöberg, Sören, 1971-
(författare)
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On the running-in of gears
- 2010
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The general trend in gear industry, today, is an increased focus on gear transmission efficiency. Gear transmission efficiency losses arise from loaded and unloaded gear contacts, seals, lubricant and bearings. One way of minimising the losses is to lower the lubricant viscosity. This will reduce the speed dependent losses. However, the load dependent losses might increase. To avoid this, the ratio between lubricant film thickness and surface roughness must be maintained, which can be fulfilled by producing smoother gear surfaces. As a starting point for this realisation process, the present manufacturing processes, the design tools and the characteristics of the gear flank interface must be further investigated and developed. This must be achieved with an emphasis on economic production.This thesis focuses on our understanding of how different gear manufacturing methods —particularly the contribution of the running-in process—affect the surface characteristics, with the view of increasing gearbox efficiency. The thesis consists of a summary and three appended papers.Paper A and paper B discuss the relationship between design parameters and real gear wheel surfaces manufactured with different manufacturing methods. The research hypothesis was that the contact area ratio is a descriptive parameter for the contact condition. Paper A deals with the influence of manufacturing method on the initial contact conditions and also serves as a validation of the simulation program used. The emphasis in Paper B is the changes that occur during running-in, and to correlate these changes to design requirements. Paper C approaches the influences of manganese phosphate-coating and lubricants with respect to friction and the risk of scuffing at the initial contact.The main conclusions of this thesis are that the contact area ratio presents a descriptive measure of how surface topography influences the contact, seen at both a global (form deviation) and local (roughness) level. The surface topography caused by the manufacturing method has a significant influence on the contact area ratio. This is an important result, since neither national standards nor commercially available gear evaluation programs handle surface topography on the local scale. Shaving was found to have the highest contact area ratio, and should therefore be the best choice if deviations from case hardening could be minimised. It is also confirmed that gear-like surfaces coated with manganese phosphate have a low coefficient of friction, and raise the limiting load for scuffing failure enormously compared to the ground equivalent.
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| 37. |
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| 38. |
- Sjöberg, Sören, et al.
(författare)
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The influence of manufacturing method on the running-in of gears
- 2011
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Ingår i: Proceedings of the Institution of mechanical engineers. Part J, journal of engineering tribology. - : SAGE Publications. - 1350-6501 .- 2041-305X. ; 225:10, s. 999-1012
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Tidskriftsartikel (refereegranskat)abstract
- Striving for higher gear transmission efficiency by using a low-viscosity transmission lubricant affects the lubricant film thickness. To keep the K-ratio (the ratio between the film thickness and the surface roughness) intact, more effort must be put on the surface topography. This paper presents a study of how running-in affects the dry elastic contact area ratio in spur gears using real surface topographies from three common manufacturing methods (green-shaving, honing, and grinding). The test gears were manufactured in case-hardened steel, similar to 20MnCrS5. Surface topography measurements were used as input to a contact analysis boundary element software program. An important hypothesis used in this work is that the dry elastic contact area ratio, i.e. the ratio between real and nominal contact area, can be used as a measure of the contact conditions in gears. It is concluded that running-in differs significantly for the studied manufacturing methods and that the dry elastic contact area ratio gives a consistent description of these changes. The shaved gears have the highest dry elastic contact area ratio after running in, where the ground gears have the lowest dry elastic contact area ratio. The increase in dry elastic contact area ratio is about 30 per cent for the shaved gears, 12 per cent for the honed gears and less than 5 per cent for the ground gears. Extreme value parameters, such as R(p) and R(z), showed relatively good correlation to dry elastic contact area ratio. However no genuine correlation could be found between dry elastic contact area ratio and two-dimensional (2D) surface roughness parameters. Furthermore, traditional gear metrology form parameters do not serve as a good measure on the changes occurring during the running-in.
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| 39. |
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| 47. |
- Yi, Changping, et al.
(författare)
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Numerical simulation for the influence of delay time on the rock fragmentation
- 2013
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Ingår i: Rock Fragmentation by Blasting, FRAGBLAST 10. - Boca Raton, Fla. : CRC Press/Balkema. - 9780415621434 - 9780203387672 ; , s. 213-220
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Konferensbidrag (refereegranskat)abstract
- With the application of electronic detonators and with short delay times, it may be possible to achieve improved fragmentation through stress wave superposition. This hypothesis was studied through a series of small scale laboratory tests. The results from these tests have subsequently been modeled using the numerical FEM code LS-DYNA and the RHT (Riedel-Hiermaier-Thoma) material model, applying a newly developed methodology for three-dimensional computer simulation of blasting. This work also involved simulating initial damage to the rock through previous blasting, and analyzing the resulting effects. The effect of different delay times showed that through a properly chosen delay time, improved fragmentation could be inferred. Moreover, the initial damage (from the previous row) clearly affected the fragmentation; however, the results indicated that longer delay times (in which the stress wave would have passed the boreholes) also resulted in improved fragmentation, implying that stress wave superposition may not be the primary factor governing fragmentation
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| 48. |
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