| 1. |
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| 2. |
- Bin Jabr, Adel, et al.
(författare)
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Chimney grafts preserve visceral flow and allow safe stenting of juxtarenal aortic occlusion.
- 2012
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Ingår i: Journal of Vascular Surgery. - : Elsevier BV. - 1097-6809 .- 0741-5214.
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Chimney grafts have proven useful for urgent endovascular repair of juxtarenal aortic aneurysms. Stenting of juxtarenal aortic occlusive disease is not routinely advocated due to the risk of visceral artery obstruction. We report on the potential applicability of chimney grafts in 10 patients with juxtarenal aortic stenosis or occlusion. To our best knowledge, chimney grafts have not been applied previously in this challenging setting. METHODS: Ten high-risk female patients (mean age, 68 years) with severe stenosis or occlusion of the aorta at the level of the visceral arteries were offered stenting. "Chimney" stents or stent grafts (20-40 mm long) were implanted from a brachial approach into visceral arteries that needed to be covered by the aortic stent. The chimney stents were then temporarily obstructed by balloon catheters to prevent visceral embolization until the aortic stent or stent graft was deployed. RESULTS: All procedures were technically successful, and patency was obtained in all visceral arteries and the aorta without distal embolization. One patient died after 9 days of acute heart failure. The nine surviving patients presented no complications, and all stented vessels remained patent at up to 6 years. Another patient died after 5.5 years due to lung cancer. All three patients with renal impairment have improved renal function, and a reduction in antihypertensive medication has been possible. CONCLUSIONS: Chimney grafts may allow stenting of juxtarenal aortic occlusive disease by protecting the patency of visceral arteries. Further evaluation with more patients and longer follow-up is required.
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| 3. |
- Börner, Gabriel, et al.
(författare)
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Percutaneous AAA Repair: Is It Safe?
- 2004
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Ingår i: Journal of Endovascular Therapy. - 1545-1550. ; 11:6, s. 621-626
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Tidskriftsartikel (refereegranskat)
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| 4. |
- Davies, Roy, et al.
(författare)
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Three applications of virtual reality for brain injury rehabilitation of daily tasks
- 2002
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Ingår i: Proceedings of the 4th International Conference on Disability, Virtual Reality & Associated Technologies. - 0704911434 ; , s. 93-100
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Konferensbidrag (refereegranskat)abstract
- Part of the process of rehabilitation after a brain injury is the relearning of various daily tasks such as preparing food, managing finances, getting from one place to another and so forth. These tasks require learning on all levels from physical to cognitive. Remembering a PIN code for a bank card, for example, can become automatic and ‘in the fingers’ after much repetition. However, other tasks require a certain cognitive process, for example, procedures must be followed, quantities estimated, numbers of items remembered or dangerous situations avoided. Even in these cases, repetition of the task many times can help fix the important aspects in the mind. This paper describes three applications of a Virtual Reality based method of rehabilitation which are a part of a larger project to investigate the potential and pitfalls of Virtual Reality technology as a complement to physical training in Brain Injury Rehabilitation. Virtual Reality has the advantage of providing a safe, controlled and highly repeatable environment that a patient can experience in a relaxed manner before having to encounter the potentially dangerous or stressful real environment. The three applications considered here are: kitchen work, an automatic teller machine (ATM) and finding ones way in a complex environment.
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| 9. |
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| 10. |
- Fujita, Satoko, et al.
(författare)
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Impact of intrasac thrombus and a patent inferior mesenteric artery on EVAR outcome.
- 2010
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Ingår i: Journal of Endovascular Therapy. - : International Society of Endovascular Specialists. - 1545-1550 .- 1526-6028. ; 17:4, s. 534-539
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To assess the significance of a patent inferior mesenteric artery (IMA) and presence of intrasac thrombus on the outcome of endovascular aneurysm repair (EVAR) for infrarenal abdominal aortic aneurysm (AAA). METHODS: Between June 2004 and June 2007, 114 AAA patients (100 men; mean age 75 years, range 56-87) treated electively with a bifurcated stent-graft were assessed with computed tomography pre- and postoperatively. Incidences of type II endoleaks and reinterventions were compared with preoperative intrasac thrombus and IMA patency. RESULTS: Over a mean follow-up of 19 months (range 6-38), there was no aneurysm rupture. Eleven (11%) of 101 patients with and 7 (54%) of 13 patients without preoperative intrasac thrombus presented with a type II endoleak (p<0.01). The postoperative change in aneurysm diameter was 0 mm (-20 to 16) in 18 patients with type II endoleak and -9 mm (-30 to 18) in sealed aneurysms (p<0.001). Fourteen (78%) type II endoleaks originated from lumbar arteries and 4 (22%) from the IMA in spite of the fact that most patients (69%) had a patent IMA. There were 5 reinterventions for type II endoleak with expansion of the sac. The reinterventions did not seem related to intrasac thrombus or a patent IMA. Prophylactic embolization of the IMA was unsuccessful in 4 (33%) cases. CONCLUSION: In this series, type II endoleaks inhibited sac shrinkage and occurred more frequently in aneurysms without intrasac thrombus. Most type II endoleaks originated from lumbar arteries and not from the IMA. Prophylactic embolization of the IMA does not seem justified and is not always technically successful.
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| 11. |
- Holst, Jan, et al.
(författare)
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Early and Intermediate Outcome of Emergency Endovascular Aneurysm Repair of Ruptured Infrarenal Aortic Aneurysm: A Single-Centre Experience of 90 Consecutive Patients.
- 2009
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Ingår i: European journal of vascular and endovascular surgery. - : Elsevier BV. - 1532-2165 .- 1078-5884. ; 37, s. 413-419
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To evaluate the early and intermediate outcome of a consecutive series of emergency endovascular aneurysm repairs (eEVAR) of computed tomography (CT)-verified infrarenal ruptured abdominal aortic aneurysm (rAAA) at a single tertiary referral centre. METHODS: Prospectively collected data of patients operated between April 2000 and October 2007 were retrospectively reviewed and all their pre-, intra- and postoperative imaging were re-evaluated. Patient and procedural data were analysed using a Cox multiregression model. RESULTS: Ninety patients (86% men, aged 76 (+/-7) years), were identified and included in the analysis. Symptom duration was <3h in 22% of patients, 3-24h in 39% and >24h in 39%. Mean aneurysmal diameter was 73 (+/-14)mm. All patients were treated with the COOK Zenith((R)) stent-graft (56% bi-iliac and 44% uni-iliac). Sixty-one percent were haemodynamically unstable on presentation, and 26% required an intra-operative aortic occlusion balloon to maintain haemodynamic stability. The 30-day and 1-year mortality rates were 27% and 37%, respectively. One-year aneurysm-related mortality was 33%. Twenty-eight percent of patients required re-interventions during the follow-up. The use of an aortic occlusion balloon and the presence of cerebrovascular disease or obstructive lung disorder correlated significantly with 30-day mortality in the multivariate analysis. CONCLUSION: EVAR is a valid treatment option for rAAA when used as a first-line method for all patients.
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| 12. |
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| 13. |
- Jönsson Belyazid, Ulrika, et al.
(författare)
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Pathogenicity of Swedish isolates of Phytophthora quercina to Quercus robur in two different soils
- 2003
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Ingår i: New Phytologist. - : Wiley. - 1469-8137 .- 0028-646X. ; 158:2, s. 355-364
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Tidskriftsartikel (refereegranskat)abstract
- Several studies have demonstrated the involvement of soil-borne Phytophthora species, especially Phytophthora quercina , in European oak decline. However, knowledge about the pathogenicity of P. quercina in natural forest soils is limited. The short-term effects of two south-Swedish isolates of P. quercina on root vitality of Quercus robur seedlings grown in two different soils, one high pH, nutrient-rich peat-sand mixture and one acid, nitrogen-rich but otherwise nutrient-poor forest soil are described. Pathogenicity of P. quercina was tested using a soil infestation method under a restricted mesic water regime without prolonged flooding of the seedlings. There was a significant difference in dead fine-root length between control seedlings and seedlings grown in soil infested with P. quercina . Trends were similar for both soil types and isolates, but there was a higher percentage of fine-root die-back and more severe damage on coarse roots in the acid forest soil. No effects on above-ground growth or leaf nutrient concentration between control seedlings and infected seedlings were found. The results confirm the pathogenicity of south-Swedish isolates of P. quercina in acid forest soils under restricted water availability. Stress-induced susceptibility of the seedlings and/or increased aggressiveness of the pathogen in the forest soil are discussed as key factors to explain the difference in root die-back between soil types.
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| 14. |
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Malina, Martin, et al.
(författare)
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Rupturerat bukaortaaneurysm. Endovaskulär behandling i lokalanestesi
- 2001
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Ingår i: Läkartidningen. - 0023-7205. ; 98:49, s. 5644-5648
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Tidskriftsartikel (refereegranskat)abstract
- We report on endovascular repair of a ruptured abdominal aortic aneurysm. A bifurcated stent graft was inserted under local anesthesia. Aortic clamping is rapidly provided by percutaneous placement of an aortic occlusion balloon catheter. Carbon dioxide can usually replace conventional contrast in patients with renal insufficiency. This minimally invasive procedure may reduce perioperative morbidity and mortality in patients with ruptured aortic aneurysms. The advantages and limitations of this novel technique are discussed.
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| 21. |
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| 22. |
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| 23. |
- Sonesson, Björn, et al.
(författare)
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Dilatation of the infrarenal aneurysm neck after endovascular exclusion of abdominal aortic aneurysm
- 1998
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Ingår i: Journal of Endovascular Surgery. - 1074-6218. ; 5:3, s. 195-200
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To determine the fate of the infrarenal aneurysm neck and suprarenal aorta after endovascular exclusion of abdominal aortic aneurysms (AAAs). METHODS: Thirty-four patients underwent endovascular AAA repair between January 1994 and December 1995 using custom-made stent-grafts constructed from polyester graft material and modified self-expanding Gianturco Z-stents sutured to the graft orifices. Thirty-one patients were available for follow-up. Pre- and postimplantation diameters were measured using spiral computed tomography in the infrarenal aneurysm neck and the suprarenal aorta at the level of the superior mesenteric artery (SMA). RESULTS: The mean follow-up time was 25 months. There was a significant increase of the diameter of the infrarenal aneurysm neck (+ 1.65 mm, p = 0.002), but not in the aorta at the level of the SMA (+0.52 mm, p = 0.100). There was no difference in the change in diameter in the infrarenal neck in the group with a stent adjacent to the level of measurement (n = 20) compared with the group without an adjacent stent (n = 11, p = 0.790). There was no correlation between preimplantation size of the infrarenal neck and its diameter change (r = 0.14, p = 0.488). There was no correlation (r = 0.10, p = 0.603) or association (chi-square test, p = 0.211) between aortic diameter change at the level of the SMA and the infrarenal neck. CONCLUSIONS: This investigation shows a significant dilatation of the infrarenal aneurysm neck, but not in the suprarenal aorta, after endovascular AAA repair with this device. The clinical significance of these findings is unclear. Whether such a dilatation in the infrarenal aneurysm neck may affect the long-term attachment of stent-grafts remains to be shown in the future.
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| 24. |
- Sonesson, Björn, et al.
(författare)
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Fixation of infrarenal aortic stent-grafts using laparoscopic banding -- an experimental study in pigs
- 2001
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Ingår i: European Journal of Vascular and Endovascular Surgery. - : Elsevier BV. - 1532-2165 .- 1078-5884. ; 21:1, s. 40-45
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: to test whether a laparoscopically-placed external band around the infrarenal aorta could stop vessel dilatation and prevent stent-graft detachment from the aortic wall. METHODS: in 13 growing pigs Gianturco-based stent-grafts were placed in the infrarenal aorta. In eight pigs, an external PTFE band (1 cm width) was placed laparoscopically around the infrarenal aorta. The remaining five pigs served as controls. Angiographic aortic diameters were measured: (1) at the most distal renal artery; (2) 1.5 cm further distally; (3) at the middle of the stent-graft; and (4) below the stent-graft, 1 cm above the aortic bifurcation. RESULTS: at a median follow-up of 16 weeks the pigs in the control group (n =5) and in the banded group ( n =7) increased their weight from 24 kg to 107 kg and 23 to 83 kg, respectively. In the control group, aortic dimensions increased by approximately 40% at all levels. In the banded group, aortic dimensions were unchanged at levels 2 and 3, but increased significantly at levels 1 and 4 (i.e. above and below the stent-graft). In the control group all stent-grafts detached causing a proximal perigraft leakage. No detachment or proximal perigraft leak was observed in the banded group. CONCLUSION: a laparoscopically placed external band around the infrarenal aorta of growing pigs seems to counteract the vessel dilatation and thereby provides a stable fixation of self-expandable stent-grafts.
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| 25. |
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| 26. |
- Sonesson, Bengt, et al.
(författare)
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Long-term reintegration and quality of life in patients with subarachnoid hemorrhage and a good neurological outcome : Findings after more than 20 years
- 2018
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Ingår i: Journal of Neurosurgery. - 0022-3085. ; 128:3, s. 785-792
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The goal of this study was to examine long-term quality of life (QOL) and reintegration in patients with good neurological recovery after aneurysmal subarachnoid hemorrhage (aSAH) and SAH of unknown cause (SAH NUD). METHODS: A long-term follow-up was performed in an original cohort of 113 individuals who had suffered SAH (93 with aSAH and 20 with SAH NUD) between 1977 and 1984. Self-reporting assessments, performed > 20 years after the bleeding episode, included the Quality of Life Scale (QOLS), Psychological General Well-Being (PGWB) index, and Reintegration to Normal Living (RNL) index, along with information on sleep disturbances and work status. RESULTS: Seventy-one survivors were identified. Questionnaires were returned by 67 individuals who had suffered SAH 20-28 years previously. The QOL was rated in the normal range for both the QOLS score (aSAH 90.3 vs SAH NUD 88.6) and the PGWB index (aSAH 105.9 vs SAH NUD 102.8). Ninety percent of patients had returned to their previous employment. Complete RNL was reported by 40% of patients with aSAH and by 46% of patients with SAH NUD; mild to moderate readjustment difficulties by 55% and 38%, respectively; and severe difficulties by 5% of patients with aSAH and 15% of patients with SAH NUD. Self-rated aspects of cognition, mood, and energy resources in addition resulted in a substantial drop in overall reintegration. Sleep disturbances were reported by 26%. CONCLUSIONS: More than half of patients with SAH who had early good neurological recovery experienced reintegration difficulties after > 20 years. However, the general QOL was not adversely affected by this impairment. Inability to return to work after SAH was associated with lower QOLS scores. Sleep disturbances were associated with lower PGWB scores.
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| 27. |
- Sonesson, Kerstin, et al.
(författare)
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Countermeasures against stress symptoms
- 2002
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Ingår i: Developing principles and models for sustainable forestry in Sweden. - 1402009992 ; , s. 249-256
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract is not available
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| 28. |
- Sonesson, Mats, et al.
(författare)
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A comparison of the physiology, anatomy and ribosomal DNA in alpine and subalpine populations of the lichen Nephroma arcticum – the effects of an eight-year transplant experiment
- 2007
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Ingår i: The Bryologist. - 0007-2745 .- 1938-4378. ; 110:2, s. 244-253
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Tidskriftsartikel (refereegranskat)abstract
- Thalli of Nephroma arcticum were transplanted between and within a high-elevation alpine heath (1100 m) and a low-elevation subalpine mountain birch forest (380 m) in northern Swedish Lapland and harvested after eight years. Statistically significant differences (P < 0.05) were found between control samples for dark respiration rates, photon use efficiencies (apparent quantum yields) and light compensation points (all were higher in the high-altitude population). The following traits were significantly affected by transplanting: (1) epicortex thickness, (2) upper cortex thickness in the low-altitude population, (3) maximum photosynthetic rates, (4) dark respiration rates and (5) light compensation point. Of these malleable traits, all reduce the differences between the controls although there seems to be over-compensation in maximum net photosynthesis and under-compensation in dark respiration rate of the low-altitude population. Conservative traits, i.e., those that did not change significantly with transplantation were: (1) thallus thickness, (2) algal layer thickness, (3) algal cell diameter and (4) light saturation level. Small, yet significant differences in anatomy and physiology suggest that an ecotypic differentiation was established although the two internal transcribed DNA spacers ITS 1 and ITS 2 showed no corresponding variation between the populations.
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| 29. |
- Sonesson, Mats, et al.
(författare)
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Growth of two peat-forming mosses in subarctic mires: species interactions and effects of simulated climate change
- 2002
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Ingår i: Oikos. - : Wiley. - 1600-0706 .- 0030-1299. ; 99:1, s. 151-160
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Tidskriftsartikel (refereegranskat)abstract
- In patches of co-occurring species in natural plant communities, there is a finely poised balance between species in the ways in which they respond to prevailing moisture and temperature regimes. However, environmental change scenarios, in which temperature, moisture and ultraviolet-B radiation are suggested to increase, may favour one of the species. The imbalance is likely to occur at the levels of interactions between patches of the different species and at the shoot level when neighbouring shoots belong to different species. We increased temperature and UV-B in a two-way factorial experiment and increased water supply independently in two subarctic mire communities dominated by the mosses Sphagnum fuscum and Dicranum elongatum. The effects of simulated increase in UV-B were studied using two separate radiation systems, i.e. a square wave system and a modulated system. When precipitation was enhanced, both species showed an increase in growth but this was not sustained beyond 5 mm per day. S. fuscum showed a 50 greater response to enhanced precipitation than did D. elongatum, as would be expected from their habitat preferences. Under ambient temperature, S. fuscum grew 67 faster than D. elongatum and this relative difference in response was maintained after one year under a temperature enhancement. The response by species over the winter period was moderated by their neighbours. S. fuscum growth was enhanced when it grew next to D. elongatum whereas D. elongatum grew better with neighbours of its own species. Increased temperature and UV-B radiation did not affect the interaction between the species. Although a balance was maintained between the two species over the short duration of the experiment, potential was shown for an imbalance to occur over longer periods and particularly if winter warming and precipitation are greater than those in summer. During the peak growing season 20 increased UV-B over ambient had a negative effect on S. fuscum under increased temperature but there were no overall seasonal effects on either species, irrespective of method of UV supplementation.
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| 30. |
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| 31. |
- Sonesson, Mats, et al.
(författare)
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Seasonal variation in concentrations of carbohydrates and lipids in two epiphytic lichens with contrasting, snow-depth related distribution on subarctic birch trees
- 2011
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Ingår i: Bryologist. - : American Bryological and Lichenological Society. - 1938-4378 .- 0007-2745. ; 114:3, s. 443-452
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Tidskriftsartikel (refereegranskat)abstract
- The lichens Parmelia olivacea and Parmeliopsis ambigua are common epiphytes in subarctic forests in Europe. They differ in abundance and vertical distribution particularly on birch trees, and these differences relate to the level and duration of the winter snow cover. Parmeliopsis ambigua is covered much of the cold season on the lower trunk whereas P. olivacea occurs well above the snow surface. Periods over 6 months under snow have no apparent effect on P. ambigua thalli while much shorter snow cover has been demonstrated to kill P. olivacea. It was hypothesized that the contrasting distributions are due to differences in growth rates and in size and quality of non-structural carbon stores in their tissues affecting their endurance to extended periods of dark respiration. To test these hypotheses, growth measurements were performed on both species and their thalli were sampled for chemical analyses. The results show that the mean annual margin extension growth of P. olivacea thalli was significantly higher than that of P. ambigua, i.e. 1.1 mm and 0.5 mm, respectively. The average non-structural carbohydrate concentration in the two species did not differ, but the annual concentration of storage lipids (triacylglycerol) in P. ambigua was four times higher than that in P. olivacea, despite a shorter growing season and lower rate of photosynthesis. The proportion of polyunsaturated fatty acids in structural (polar) lipids was high in both species, i.e. 77% in P. olivacea and 64% in P. ambigua, which appears to enable both species to withstand low ambient thallus temperatures. The higher concentration of storage lipids in P. ambigua allows survival in environments where P. olivacea would respire to death, e.g. under a prolonged snow cover. Parmeliopsis ambigua avoids competition by establishing toward the base of the tree trunk, where P. olivacea would not survive.
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| 32. |
- Stjernquist, Ingrid, et al.
(författare)
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Forest health indicators.
- 2002
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Ingår i: Developing principles and models for sustainable forestry in Sweden. - 1402009992
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract is not available
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| 33. |
- Wallergård, Mattias, et al.
(författare)
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A Virtual Cash Dispenser for Persons with Acquired Brain Injury
- 2001
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Ingår i: Proceedings of the international conference on computer-aided ergonomics and safety. - 8493113476
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Konferensbidrag (refereegranskat)abstract
- Brain injury rehabilitation is a long and difficult process that includes training of so-called instrumental activities of daily living (IADL). This type of training involves activities like preparing meals, doing housework, grocery shopping etc. and it is often used by occupational therapists when they teach brain injury patients how to manage their daily life. A computer-generated Virtual Environment (VE) that is to be used as a tool in IADL training has been designed. The VE has the shape of a cash dispenser and it can be used by a brain injury patient that wants to practice the activity of withdrawing money. The aim was to design a VE interface that puts as little cognitive load as possible on the brain injury patient, so that he or she can focus completely on the task of withdrawing money. A low-fidelity paper prototype was built and evaluated in order to generate ideas regarding object behaviour, navigation of the viewpoint, interaction with objects and other features. The result of the project so far is a computer prototype built with a Virtual Reality (VR) development kit called WorldUp, a personal computer based VR system. The computer prototype behaves exactly like a real cash dispenser and it has a function that allows the patient to learn his or her banking code. Feedback and clues will be provided by the occupational therapist that sits next to the patient during the training sessions. At present tests are in progress with voluntary brain injury patients in a usability laboratory. These tests aim to evaluate the virtual cash dispenser in order to get ideas on how to increase its usability. The tests also aim to collect ideas on future functions and features and also to get clues on how VE training can be integrated into the rehabilitation process.
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| 34. |
- Wallergård, Mattias, et al.
(författare)
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Developing virtual vending and automatic service machines for brain injury rehabilitation
- 2002
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Ingår i: Proceeding of the 4th international conference on disability, virtual reality and associated technologies. - 0704911434 ; , s. 109-114
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Konferensbidrag (refereegranskat)abstract
- Two different approaches for developing virtual environments (VE) for brain injury rehabilitation are described and discussed. The two VEs are built with the VR software World Up in the form of virtual vending and automatic service machines. The result from the first approach is a virtual cash dispenser that has been tested on five patients with brain injury. Improving the VE according to the test results was found to be quite hard, since it is implemented in a way that makes it difficult to update the code. In the second approach independent programming modules were identified and isolated. The modules were used to build a VE in the form of a train ticket machine. The second approach seems to provide a fast and understandable way of building virtual vending and automatic service machines for brain injury rehabilitation. There might also be the possibility to add a graphical user interface on top of the modules so that, for example, an occupational therapist with no programming experience could build an arbitrary virtual vending machine.
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| 35. |
- Wallergård, Mattias, et al.
(författare)
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Initial usability testing of navigation and interaction methods in virtual environments: Developing usable interfaces for brain injury rehabilitation
- 2007
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Ingår i: Presence. - 1054-7460. ; 16:1, s. 16-44
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Tidskriftsartikel (refereegranskat)abstract
- It is speculated that virtual environments (VE) might be used as a training tool in brain injury rehabilitation. The rehabilitation process often involves practicing so-called instrumental activities of daily living (IADL), such as shopping, cooking, and using a telephone. If a brain injury patient is to practice such activities in a VE, the patient must be able to navigate the viewpoint and interact with virtual objects in an understandable way. People with brain injury may be less tolerant to a poor interface and a VE might therefore become unusable due to, for example, an unsuitable input device. In this paper we present two studies aimed to do initial usability testing of VE interaction methods on people without experience of 3D computer graphics. In the first study four navigation input device configurations were compared: the IntelliKeys keyboard and the Microsoft Sidewinder joystick, both programmed with two and three degrees of freedom (DOF). The purpose of the second study was to evaluate a method for interaction with objects, and to find a sufficiently usable input device for this purpose. The keyboard was found to be more suitable for navigation tasks in which the user wants to give the viewpoint a more advantageous position and orientation for carrying out a specific task. No big differences could be found between two and three DOFs. The method for interaction with objects was found to work sufficiently well. No difference in performance could be found between mouse and touch screen, but some evidence was found that they affect the usability of the VE interface in different ways.
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