Rapid formation of new migration route and breeding area by Arctic geese.

Many Arctic-breeding animals are at risk from local extirpation associated with habitat constriction and alterations in phenology in their Arctic environment as a result of rapid global warming.1 Migratory species face additional increasing anthropogenic pressures along their migratory routes such as habitat destruction, droughts, creation of barriers, and overexploitation.2,3 Such species can only persist if they adjust their migration, timing of breeding, and range.4 Here, we document both the abrupt (∼10 years) formation of a new migration route and a disjunct breeding population of the pink-footed goose (Anser brachyrhynchus) on Novaya Zemlya, Russia, almost 1,000 km away from the original breeding grounds in Svalbard. The population has grown to 3,000-4,000 birds, explained by intrinsic growth and continued immigration from the original route. The colonization was enabled by recent warming on Novaya Zemlya. We propose that social behavior of geese, resulting in cultural transmission of migration behavior among conspecifics as well as in mixed-species flocks, is key to this fast development and acts as a mechanism enabling ecological rescue in a rapidly changing world.

Effectiveness of the European Natura 2000 network to sustain a specialist wintering waterbird population in the face of climate change.

Analysis of coordinated Greater Scaup (Aythya marila) count data from the last 30 years showed a 38.1% decrease in wintering numbers in North-West Europe, from 309,000 during 1988-1991 to c.192,300 individuals during 2015-2018. Annual trends in wintering numbers differed throughout the range. Numbers decreased in the UK, Ireland, and in the Netherlands, while numbers were stable in Denmark. Germany, Poland, Sweden, and Estonia showed increasing numbers, suggesting a shift in the distribution of the species within its wintering grounds towards the east and north. Higher temperatures in northern and eastern areas were correlated with the range shift of the wintering distribution. Deaths from bycatch drowning of Scaup in fishing gear have significantly decreased in recent decades in the Netherlands, where currently the greatest threat is considered the deterioration of food resources. The increasing concentration of wintering Scaup in coastal Poland and Germany (where lack of effective implementation of conservation measures fail to protect the species from the impacts of bycatch and declining food quality) pose major threats to the entire population.

Application of cryoenergy to improve septal exposure during transaortic septal myectomy in hypertrophic obstructive cardiomyopathy.

For the past few decades, the transaortic septal myectomy (Morrow's procedure) has been the gold standard for treating severe left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy (HOCM) patients. 30-day mortality has been reported at less than 1% in dedicated centers. However, in a subgroup of patients, the interventricular septal obstruction is localized very distally, below the aortic valve plane, and the transaortic approach can be very challenging. A subset of these patients can present with residual obstruction after surgery, due to inadequate length of septal excision, leading to reoperation. The aim of this work is to illustrate an original application of cryoenergy to improve the transaortic exposure of the interventricular septum and thus enable surgeons to perform very distal myectomies in HOCM patients.

Latitudinal-Related Variation in Wintering Population Trends of Greylag Geese (Anser Anser) along the Atlantic Flyway: A Response to Climate Change?

The unusually high quality of census data for large waterbirds in Europe facilitates the study of how population change varies across a broad geographical range and relates to global change. The wintering population of the greylag goose Anser anser in the Atlantic flyway spanning between Sweden and Spain has increased from 120 000 to 610 000 individuals over the past three decades, and expanded its wintering range northwards. Although population sizes recorded in January have increased in all seven countries in the wintering range, we found a pronounced northwards latitudinal effect in which the rate of increase is higher at greater latitudes, causing a constant shift in the centre of gravity for the spatial distribution of wintering geese. Local winter temperatures have a strong influence on goose numbers but in a manner that is also dependent on latitude, with the partial effect of temperature (while controlling for the increasing population trend between years) being negative at the south end and positive at the north end of the flyway. Contrary to assumptions in the literature, the expansion of crops exploited by greylag geese has made little contribution to the increases in population size. Only in one case (expansion of winter cereals in Denmark) did we find evidence of an effect of changing land use. The expanding and shifting greylag population is likely to have increasing impacts on habitats in northern Europe during the course of this century.

Membrane treatment of the bleaching plant (EPO) filtrate of a kraft pulp mill.

The objective of this study was to evaluate the use of membrane technology to treat oxygen and peroxide-reinforced extraction stage (EPO) filtrate from a kraft pulp mill bleach plant. Three different types of tubular membranes were tested in a pilot plant: (i) tight ultrafiltration (UF); (ii) open UF followed by nanofiltration (UF+NF); and (iii) nanofiltration (NF). According to the separation performance, considering the chemical oxygen demand (COD) and colour removal, permeate flux, operational simplicity and cost, the results indicated that the best option for treatment of (EPO) filtrates was the tight UF membrane. This membrane obtained a COD removal of 79% with a colour reduction of 86%. The effect of (EPO) filtrate UF treatment on the mill effluent treatment plant was evaluated. Compared with the actual mill effluent, the results indicated that if the UF permeate was recycled in the bleaching area, the COD reduction efficiency increased by 7%, the final effluent colour decreased by 8%, the biological sludge production decreased by 18%, and the energy consumption decreased by 40%. In the tertiary treatment plant, the coagulant dosage decreased by 40%, and the tertiary sludge production decreased by 46%.

Adrenal response after trauma is affected by time after trauma and sedative/analgesic drugs.

BACKGROUND: The adrenal response in critically ill patients, including trauma victims, has been debated over the last decade. The aim of this study was to assess the early adrenal response after trauma. METHODS: Prospective, observational study of 50 trauma patients admitted to a level-1-trauma centre. Serum and saliva cortisol were followed from the accident site up to five days after trauma. Corticosteroid binding globulin (CBG), dehydroepiandrosterone (DHEA) and sulphated dehydroepiandrosterone (DHEAS) were obtained twice during the first five days after trauma. The effect of time and associations between cortisol levels and; severity of trauma, infusion of sedative/analgesic drugs, cardiovascular dysfunction and other adrenocorticotropic hormone (ACTH) dependent hormones (DHEA/DHEAS) were studied. RESULTS: There was a significant decrease over time in serum cortisol both during the initial 24 h, and from the 2nd to the 5th morning after trauma. A significant decrease over time was also observed in calculated free cortisol, DHEA, and DHEAS. No significant association was found between an injury severity score ≥ 16 (severe injury) and a low (< 200 nmol/L) serum cortisol at any time during the study period. The odds for a serum cortisol < 200 nmol/L was eight times higher in patients with continuous infusion of sedative/analgesic drugs compared to patients with no continuous infusion of sedative/analgesic drugs. CONCLUSION: Total serum cortisol, calculated free cortisol, DHEA and DHEAS decreased significantly over time after trauma. Continuous infusion of sedative/analgesic drugs was independently associated with serum cortisol < 200 nmol/L.

Saliva stimulation with glycerine and citric acid does not affect salivary cortisol levels.

OBJECTIVE: In critically ill patients with hypotension, who respond poorly to fluids and vasoactive drugs, cortisol insufficiency may be suspected. In serum over 90% of cortisol is protein-bound, thus routine measures of total serum cortisol may yield 'false lows' due to hypoproteinaemia. Thus, the occurrence of cortisol insufficiency could be overestimated in critically ill patients. Salivary cortisol can be used as a surrogate for free serum cortisol, but in critically ill patients saliva production is decreased, and insufficient volume of saliva for analysis is a common problem. The aim of this study was to investigate if a cotton-tipped applicator with glycerine and citric acid could be used for saliva stimulation without affecting salivary cortisol levels. DESIGN: Prospective, observational study. PARTICIPANTS: Thirty-six volunteers (six males, 30 females), age 49 ± 9 years, without known oral mucus membrane rupture in the mouth. MEASUREMENTS: Forty-two pairs of saliva samples (22 paired morning samples, 20 paired evening samples) were obtained before and after saliva stimulation with glycerine and citric acid. Salivary cortisol was analysed using Spectria Cortisol RIA (Orion Diagnostica, Finland). RESULTS: The paired samples correlated significantly (P < 0.0001) and there was no significant difference between un-stimulated and stimulated salivary cortisol levels. CONCLUSIONS: Saliva stimulation with a cotton-tipped applicator containing glycerine and citric acid did not significantly influence salivary cortisol levels in healthy volunteers. This indicates that salivary cortisol measurement after saliva stimulation may be a useful complement when evaluating cortisol status in critically ill patients.

Investigation of lead concentrations in whole blood, plasma and urine as biomarkers for biological monitoring of lead exposure.

Lead in blood is a major concept in biomonitoring of exposure but investigations of its alternatives are scarce. The aim of the study was to describe different lead biomarkers' variances, day-to-day and between individuals, estimating their fraction of the total variance. Repeated sampling of whole blood, plasma and urine were conducted for 48 lead-exposed men and 20 individuals under normal environmental lead exposure, in total 603 measurements. For lead workers, the fraction of the total variance attributed to differences between individuals was 91% for whole-blood lead (geometric mean 227 µg/l; geometric standard deviation (GSD): 1.55 µg/l); plasma 78% (0.57 µg/l; GSD: 1.84 µg/l); density-adjusted urine 82%; and unadjusted urine 75% (23.7 µg/l; GSD: 2.48 µg/l). For the individuals under normal lead exposure, the corresponding fractions were 95% of the total variance for whole blood (20.7 µg/l; GSD: 8.6 µg/l), 15% for plasma (0.09 µg/l; GSD: 0.04 µg/l), 87% for creatinine-adjusted urine and 34% for unadjusted (10.8 µg/l; GSD: 6.7 µg/l). Lead concentration in whole blood is the biomarker with the best ability to discriminate between individuals with different mean concentration. Urinary and plasma lead also performed acceptably in lead workers, but at low exposures plasma lead was too imprecise. Urinary adjustments appear not to increase the between-individual fraction of the total variance among lead workers but among those with normal lead exposure.

Determinants explaining the variability of hand-transmitted vibration emissions from two different work tasks: grinding and cutting using angle grinders.

BACKGROUND: There are numerous factors including physical, biomechanical, and individual that influence exposure to hand-transmitted vibration (HTV) and cause variability in the exposure measurements. Knowledge of exposure variability and determinants of exposure could be used to improve working conditions. We performed a quasi-experimental study, where operators performed routine work tasks in order to obtain estimates of the variance components and to evaluate the effect of determinants, such as machine-wheel combinations and individual operator characteristics. METHODS: Two pre-defined simulated work tasks were performed by 11 operators: removal of a weld puddle of mild steel and cutting of a square steel pipe. In both tasks, four angle grinders were used, two running on compressed air and two electrically driven. Two brands of both grinding and cutting wheels were used. Each operator performed both tasks twice in a random order with each grinder and wheel and the time to complete each task was recorded. Vibration emission values were collected and the wheel wear was measured as loss of weight. Operators' characteristics collected were as follows: age, body height and weight, length and volume of their hands, maximum hand grip force, and length of work experience with grinding machines (years). The tasks were also performed by one operator who used four machines of the same brand. Mixed and random effects models were used in the statistical evaluation. RESULTS: The statistical evaluation was performed for grinding and cutting separately and we used a measure referring to the sum of the 1-s r.m.s. average frequency-weighted acceleration over time for completing the work task (a(sa)). Within each work task, there was a significant effect as a result of the determinants 'the machine used', 'wheel wear', and 'time taken to complete the task'. For cutting, 'the brand of wheel' used also had a significant effect. More than 90% of the inherent variability in the data was explained by the determinants. The two electrically powered machines had a mean a(sa) that was 2.6 times higher than the two air-driven machines. For cutting, the effect of the brand of wheel on a(sa) was ~0.1 times. The a(sa) increased both with increasing wheel wear and with time taken to complete the work task. However, there were also a number of interaction effects which, to a minor extent, modified the a(sa). Only a minor part (1%) of the total variability was attributed to the operator: for cutting, the volume of the hands, maximum grip force, and body weight were significant, while for grinding, it was the maximum grip force. There was no clear difference in a(sa) between the four copies of the same brand of each machine. CONCLUSIONS: By including determinants that were attributed to the brand of both machine and wheel used as well as the time taken to complete the work task, we were able to explain >90% of the variability. The dominating determinant was the brand of the machine. Little variability was found between operators, indicating that the overall effect as due to the operator was small.

Rapid climate driven shifts in wintering distributions of three common waterbird species.

Climate change is predicted to cause changes in species distributions and several studies report margin range shifts in some species. However, the reported changes rarely concern a species' entire distribution and are not always linked to climate change. Here, we demonstrate strong north-eastwards shifts in the centres of gravity of the entire wintering range of three common waterbird species along the North-West Europe flyway during the past three decades. These shifts correlate with an increase of 3.8 °C in early winter temperature in the north-eastern part of the wintering areas, where bird abundance increased exponentially, corresponding with decreases in abundance at the south-western margin of the wintering ranges. This confirms the need to re-evaluate conservation site safeguard networks and associated biodiversity monitoring along the flyway, as new important wintering areas are established further north and east, and highlights the general urgency of conservation planning in a changing world. Range shifts in wintering waterbirds may also affect hunting pressure, which may alter bag sizes and lead to population-level consequences.

Lung function in volunteers before and after exposure to trichloramine in indoor pool environments and asthma in a cohort of pool workers.

OBJECTIVES: Exposure to trichloramine (NCl(3)) in indoor swimming-pool environments is known to cause mucous membrane irritation, but if it gives rise to changes in lung function or asthma in adults is not known. (1) We determined lung function in volunteers before and after exposure to indoor pool environments. (2) We studied the occurrence of respiratory symptoms and asthma in a cohort of pool workers. DESIGN/METHODS/PARTICIPANTS: (1) We studied two groups of volunteers, 37 previously non-exposed healthy persons and 14 pool workers, who performed exercise for 2 h in an indoor pool environment. NCl(3) in air was measured during pool exposures and in 10 other pool environments. Filtered air exposures were used as controls. Lung function and biomarkers of pulmonary epithelial integrity were measured before and after exposure. (2) We mailed a questionnaire to 1741 persons who indicated in the Swedish census 1990 that they worked at indoor swimming-pools. RESULTS: (1) In previously non-exposed volunteers, statistically significant decreases in FEV(1) (forced expiratory volume) and FEV(%) (p=0.01 and 0.05, respectively) were found after exposure to pool air (0.23 mg/m(3) of NCl(3)). In pool workers, a statistically significant decrease in FEV(%) (p=0.003) was seen (but no significant change of FEV(1))(.) In the 10 other pool environments the median NCl(3) concentration was 0.18 mg/m(3). (2) Our nested case/control study in pool workers found an OR for asthma of 2.31 (95% CI 0.79 to 6.74) among those with the highest exposure. Exposure-related acute mucous membrane and respiratory symptoms were also found. CONCLUSIONS: This is the first study in adults showing statistically significant decreases in lung function after exposure to NCl(3). An increased OR for asthma among highly exposed pool workers did not reach statistical significance, but the combined evidence supports the notion that current workroom exposures may contribute to asthma development. Further research on sensitive groups is warranted.

Atrial function after left atrial epicardial cryoablation for atrial fibrillation in patients undergoing mitral valve surgery.

PURPOSE: To explore the effects on atrial and ventricular function of restoring sinus rhythm (SR) after epicardial cryoablation and closure of the left atrial appendage (LAA) in patients with mitral valve disease and atrial fibrillation (AF) undergoing surgery. METHODS: Sixty-five patients with permanent AF were randomized to mitral valve surgery combined with left atrial epicardial cryoablation and LAA closure (ABL group, n = 30) or to mitral valve surgery alone (control group, n = 35). Two-dimensional and Doppler echocardiography were performed before and 6 months after surgery. RESULTS: At 6 months, 73% of the patients in the ABL group and 46% of the controls were in SR. Patients in SR at 6 months had a reduction in their left ventricular diastolic diameter while the left ventricular ejection fraction was unchanged. In patients remaining in AF, the left ventricular ejection fraction was lower than at baseline. The left atrial diastolic volume was reduced after surgery, more in patients with SR than AF. In patients in SR, the peak velocity during the atrial contraction and the reservoir function were lower in the ABL group than in the control group. CONCLUSIONS: In patients in SR, signs of atrial dysfunction were observed in the ABL but not the control group. Atrial dysfunction may have existed before surgery, but the difference between the groups implies that the cryoablation procedure and/or closure of the LAA might have contributed.

Variability in hand-arm vibration during grinding operations.

BACKGROUND: Measurements of exposure to vibrations from hand-held tools are often conducted on a single occasion. However, repeated measurements may be crucial for estimating the actual dose with good precision. In addition, knowledge of determinants of exposure could be used to improve working conditions. The aim of this study was to assess hand-arm vibration (HAV) exposure during different grinding operations, in order to obtain estimates of the variance components and to evaluate the effect of work postures. METHODS: Ten experienced operators used two compressed air-driven angle grinders of the same make in a simulated work task at a workplace. One part of the study consisted of using a grinder while assuming two different working postures: at a standard work bench (low) and on a wall with arms elevated and the work area adjusted to each operator's height (high). The workers repeated the task three times. In another part of the study, investigating the wheel wear, for each grinder, the operators used two new grinding wheels and with each wheel the operator performed two consecutive 1-min grinding tasks. Both grinding tasks were conducted on weld puddles of mild steel on a piece of mild steel. Measurements were taken according to ISO-standard 5349 [the equivalent hand-arm-weighted acceleration (m s(-2)) averaged over 1 min]. Mixed- and random-effects models were used to investigate the influence of the fixed variables and to estimate variance components. RESULTS: The equivalent hand-arm-weighted acceleration assessed when the task was performed on the bench and at the wall was 3.2 and 3.3 m s(-2), respectively. In the mixed-effects model, work posture was not a significant variable. The variables 'operator' and 'grinder' together explained only 12% of the exposure variability and 'grinding wheel' explained 47%; the residual variability of 41% remained unexplained. When the effect of grinding wheel wear was investigated in the random-effects model, 37% of the variability was associated with the wheel while minimal variability was associated with the operator or the grinder and 37% was unexplained. The interaction effect of grinder and operator explained 18% of the variability. In the wheel wear test, the equivalent hand-arm-weighted accelerations for Grinder 1 during the first and second grinding minutes were 3.4 and 2.9 m s(-2), respectively, and for Grinder 2, they were 3.1 and 2.9 m s(-2), respectively. For Grinder 1, the equivalent hand-arm-weighted acceleration during the first grinding minute was significantly higher (P = 0.04) than during the second minute. CONCLUSIONS: Work posture during grinding operations does not appear to affect the level of HAV. Grinding wheels explained much of the variability in this study, but almost 40% of the variance remained unexplained. The considerable variability in the equivalent hand-arm-weighted acceleration has an impact on the risk assessment at both the group and the individual level.

Effects of Qigong in patients with burnout: a randomized controlled trial.

OBJECTIVE: To evaluate the efficacy of Qigong in rehabilitation for patients with burnout. DESIGN: Prospective, randomized controlled trial. SUBJECTS: Eighty-two patients (68 women and 14 men, mean age 44.3 (standard deviation 9.1) years) diagnosed with burnout. METHODS: Basic care was offered to both the intervention and the control group. Patients in the intervention group received basic care and, in addition, performed Qigong twice a week for 12 weeks. Psychological variables, health-related quality of life, perceived relaxation and physical measurements were assessed at baseline and after the intervention period. RESULTS: No significant difference in treatment efficacy between the groups was found by either intention-to-treat or per-protocol analyses. Both groups improved significantly over time, with reduced levels of burnout, fatigue, anxiety and depression, and increased dynamic balance and physical capacity. CONCLUSION: In this study, a Qigong intervention twice a week for 12 weeks had no additional effect beyond basic care for patients with burnout.

A high quality of life is maintained late after Maze III surgery for atrial fibrillation.

BACKGROUND: Cox Maze surgery for atrial fibrillation (AF) has been found to have high efficacy in maintaining sinus rhythm and has been shown to improve quality of life early after surgery, but reports on long-term effects in this respect are lacking. This study was therefore undertaken to evaluate the effect of the Maze procedure on health-related quality of life in the long term. METHODS: Patients with drug-refractory AF undergoing the 'cut and sew' Maze III procedure without any modification were assessed with the SF-36 Health Survey regarding quality of life at baseline and late after surgery. Totally 61 patients, mean age 55 years (range: 29-74 years), were evaluated. At the time of surgery, 34 patients (56%) had paroxysmal or persistent AF and the remainder had permanent AF. RESULTS: At late follow-up, at a mean of 55+/-12 months, 54 patients (89%) were free from AF recurrences and another five patients (8%) had experienced only one or a few AF episodes. All eight scales on the SF-36 Health Survey were significantly improved at long-term follow-up compared to baseline. The quality-of-life improvement was seen both in patients with paroxysmal/persistent AF and in those with permanent AF. At long-term follow-up, the quality-of-life scores were comparable with those of the general population. CONCLUSIONS: The Cox Maze III procedure has good long-term efficacy for rhythm control in patients with medically refractory AF, resulting in a quality-of-life improvement, which is maintained late after surgery.

Epicardial off-pump pulmonary vein isolation and vagal denervation improve long-term outcome and quality of life in patients with atrial fibrillation.

OBJECTIVES: The limited information available on thoracoscopic pulmonary vein isolation combined with ganglionated plexi ablation and the lack of studies regarding its effect on quality of life and physical capacity urged us to study its acute and long-term results in patients with atrial fibrillation. METHODS: Forty-three patients (mean age 57.1 years) with symptomatic atrial fibrillation referred for thoracoscopic off-pump epicardial pulmonary vein isolation and ganglionated plexi ablation using radiofrequency energy were included. RESULTS: The physical capacity improved significantly at 6-month follow-up compared with baseline (mean +/- standard deviation, 165.2 +/- 65 Watt versus 155.9 +/- 57 Watt, P = .02). Quality of life (Short Form-36 health survey) significantly improved 12 months after surgery compared with baseline in all subscales except for bodily pain. The symptom severity questionnaire score decreased significantly from mean 15.2 +/- 4.0 points to 10.7 +/- 4.8 points (P = .02). Overall, 25 of 33 patients (76%) followed up for 12 months had no symptomatic atrial fibrillation recurrences or atrial fibrillation episodes on 24-hour Holter recordings. The corresponding figures were 79% (19/24) for patients with paroxysmal atrial fibrillation, 100% (2/2) for persistent atrial fibrillation, and 57% (4/7) for permanent atrial fibrillation. The most common complication was bleeding events (9%) during pulmonary vein dissection. CONCLUSIONS: Epicardial off-pump pulmonary vein isolation combined with ganglionated plexi ablation improved quality of life, symptoms, and exercise capacity and therefore may be considered for patients with atrial fibrillation who fail endocardial pulmonary vein ablation or as a first-line procedure if left atrial appendage exclusion is warranted.

Potential dermal exposure to methyl methacrylate among dental technicians; variability and determinants in a field study.

Methyl methacrylate (MMA) is a commonly used chemical in dental work that can cause dermatitis. Nineteen dental technicians participated in a field study in which potential dermal exposure to MMA and exposure determinants, including glove use and MMA vapour in the breathing zone, were repeatedly monitored during three consecutive days. Using patches placed on various parts of their hands we observed that the fingers and palms of the dental technicians were exposed to MMA, and their forefingers were significantly more exposed than their ring fingers; this is based on pooled data for both left and right hands (p = 0.04). The exposure variability was greater between workers than within worker (i.e. day-to-day variability), but the between worker variability was to some extent explained by a model which included the tested determinants. Neither the amount of MMA vapours in the breathing zone nor glove use was consistently correlated with the dermal exposure. Thus, the effects of glove use and the distribution of exposure to MMA on the hands in working environments needs to be further investigated.

Cognitively oriented behavioral rehabilitation in combination with Qigong for patients on long-term sick leave because of burnout: REST--a randomized clinical trial.

BACKGROUND: Despite an increase in the occurrence of burnout, there is no agreement on what kind of rehabilitation these patients should be offered. PURPOSE: Primary aim of this study was to evaluate effects on psychological variables and sick leave rates by two different group rehabilitation programs for patients on long-term sick leave because of burnout. Rehabilitation program A (Cognitively oriented Behavioral Rehabilitation (CBR) and Qigong) was compared with rehabilitation program B (Qigong only). METHOD: In a randomized clinical trial, 96 women and 40 men with a mean age of 41.6 +/- 7.4 years were allocated to one of the two rehabilitation programs. RESULTS: A per-protocol analysis showed no significant difference in treatment efficacy between the groups. Both groups improved significantly over time with reduced levels of burnout, self-rated stress behavior, fatigue, depression, anxiety, obsessive-compulsive symptoms, and sick leave rates. In an intention-to-treat analysis, patients in program A had fewer obsessive-compulsive symptoms and larger effect sizes in self-rated stress behavior and obsessive-compulsive symptoms compared to patients in program B. CONCLUSION: This study showed no differences in effect between CBR and Qigong compared with Qigong only in a per-protocol analysis. Both rehabilitation programs showed positive effect for patients with burnout.

Diffusion dynamics of motor-driven transport: gradient production and self-organization of surfaces.

The interaction between cytoskeletal filaments (e.g., actin filaments) and molecular motors (e.g., myosin) is the basis for many aspects of cell motility and organization of the cell interior. In the in vitro motility assay (IVMA), cytoskeletal filaments are observed while being propelled by molecular motors adsorbed to artificial surfaces (e.g., in studies of motor function). Here we integrate ideas that cytoskeletal filaments may be used as nanoscale templates in nanopatterning with a novel approach for the production of surface gradients of biomolecules and nanoscale topographical features. The production of such gradients is challenging but of increasing interest (e.g., in cell biology). First, we show that myosin-induced actin filament sliding in the IVMA can be approximately described as persistent random motion with a diffusion coefficient (D) given by a relationship analogous to the Einstein equation (D = kT/gamma). In this relationship, the thermal energy (kT) and the drag coefficient (gamma) are substituted by a parameter related to the free-energy transduction by actomyosin and the actomyosin dissociation rate constant, respectively. We then demonstrate how the persistent random motion of actin filaments can be exploited in conceptually novel methods for the production of actin filament density gradients of predictable shapes. Because of regularly spaced binding sites (e.g., lysines and cysteines) the actin filaments act as suitable nanoscale scaffolds for other biomolecules (tested for fibronectin) or nanoparticles. This forms the basis for secondary chemical and topographical gradients with implications for cell biological studies and biosensing.

Long-term effects of the maze procedure on atrial size and mechanical function.

BACKGROUND: The Maze procedure is effective in restoring sinus rhythm, but the extensive procedure may have negative effects on atrial mechanical function. Decreased atrial contractility has been observed early after the Maze procedure. The purpose of this study was to determine the long-term effect of the Maze procedure on atrial size and mechanical function. METHODS: Fifty-two patients with symptomatic atrial fibrillation, without structural heart or valvular disease, underwent the Cox Maze III procedure. Atrial size and mechanical function were assessed by echocardiographic examination at baseline and postoperatively at a mean +/- SD of 6 +/- 1 and 56 +/- 12 months. RESULTS: The left atrial area was decreased 6 months after the procedure compared with baseline (mean, 15.4 +/- 3.3 vs 17.6 +/- 3.2 cm2, p < 0.01). By 56 months, however, the left atrial area had increased compared with the 6-month follow-up (19.5 +/- 3.9 vs 15.4 +/- 3.3 cm2, p < 0.001), resulting in no difference in left atrial size compared with the baseline values. The left atrial contractility, measured as fractional area change, was significantly reduced at 6 and 56 months of follow-up (0.20 +/- 0.09 and 0.19 +/- 0.07 vs baseline 0.36 +/- 0.09), as was the transmitral A-wave velocity (30 +/- 12 and 28 +/- 8 cm/s vs baseline 40 +/- 15). The same pattern was seen for the right atrium. CONCLUSIONS: This study shows that the Maze procedure results in a sustained decrease in atrial contractility. The initial reduction in atrial size is later reversed. These findings contradict late improvements in atrial mechanical function after Maze surgery and may have important implications for the risk of thromboembolic complications.