Multiproduct firms often diversify into technologically related activities to exploit efficiencies of joint production; however, unrelated products in the company's portfolio provide access to distinct markets and can help to avoid industry-specific shocks. Yet, the underlying mechanisms of related and unrelated diversification are still poorly understood. Here we investigate diversification decisions of firms in periods when corporations' markets are hit by a demand shocks.
View Article and Find Full Text PDFIn addition to economic and infrastructural factors, social connections of people also influence migration patterns. This influence can be attributed to the resources that are made available by social contacts: social capital, which can also be utilized in the process of migration. Based on previous literature, we identify three different aspects of social capital and test their relationship with domestic migration simultaneously.
View Article and Find Full Text PDFDo labor mobility and co-worker networks contribute to convergence or divergence between regions? Based on the previous literature, labor mobility contributes to knowledge transfer between firms. Therefore, mobility may contribute to decreasing productivity differences, while limited mobility sustains higher differences. The effect of co-worker networks, however, can be two-fold in this process; they transmit information about potential jobs, which may enhance the mobility of workers-even between regions-and this enhanced mobility may contribute to levelling of differences.
View Article and Find Full Text PDFGait dysfunction is common in patients with multiple sclerosis (PwMS). Treatment with prolonged-release fampridine (PR-fampridine) improves walking ability in some PwMS. Associated fampridine-induced changes in the walking pattern are still poorly understood but may provide a better understanding of the mechanisms underlying the beneficial drug effects.
View Article and Find Full Text PDFBackground: Walking dysfunction is common in people with multiple sclerosis (MS). Besides walking speed or endurance, one crucial feature of ambulatory function is the ability to adjust the gait pattern according to walking speed which relies on the integrity of spinal motor centres, their reciprocal connections to supraspinal networks and peripheral sensory input.
Objective: To investigate the capacity of people with MS to modify their gait pattern in response to changes in walking speed.
Accurate functional outcome measures are critical for both clinical trials and routine patient assessments. Many functional outcomes improve with test repetition, a phenomenon that can confound the findings of longitudinal assessments. In this viewpoint, we tackle the poorly considered issue of practice effects in prevailing clinical walking tests based on current literature, while also presenting the original data from our own work, in which we investigated practice effects in the timed 25-foot walk (T25FW), timed-up and go (TUG), and 2-minute walk test (2MWT).
View Article and Find Full Text PDFLocomotion relies on the fine-tuned coordination of different muscles which are controlled by particular neural circuits. Depending on the attendant conditions, walking patterns must be modified to optimally meet the demands of the task. Assessing neuromuscular control during dynamic conditions is methodologically highly challenging and prone to artifacts.
View Article and Find Full Text PDFGait dysfunction is a common and relevant symptom in multiple sclerosis (MS). This study aimed to profile gait pathology in gait-impaired patients with MS using comprehensive 3D gait analysis and clinical walking tests. Thirty-seven patients with MS walked on the treadmill at their individual, sustainable speed while 20 healthy control subjects walked at all the different patient's paces, allowing for comparisons independent of walking velocity.
View Article and Find Full Text PDFMinimum toe clearance (MTC) occurs during a highly dynamic phase of the gait cycle and is associated with the highest risk of unintentional contact with obstacles or the ground. Age, cognitive function, attention and visual feedback affect foot clearance but how these factors interact to influence MTC control is not fully understood. We measured MTC in 121 healthy individuals aged 20-80 under four treadmill walking conditions; normal walking, lower visual field restriction and two Stroop colour/word naming tasks of two difficulty levels.
View Article and Find Full Text PDFHuman arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task-primarily involving left hemisphere structures-would reduce right arm swing only.
View Article and Find Full Text PDFObjective: To expand upon the limited knowledge of the long-term effects of prolonged-release (PR) fampridine in patients with multiple sclerosis (PwMS) regarding safety, walking improvements, and changes in drug responsiveness.
Methods: Fifty-three PwMS who completed the FAMPKIN core study were included in this extension trial. Drug efficacy was assessed in an open-label and randomized double-blind, placebo-controlled study design with regular baseline assessments over a period of 2 years using the Timed 25-Foot Walk (T25FW), 6-Minute Walk Test (6MWT), and 12-item MS Walking Scale (MSWS-12) as outcome measures.
Psychological problems may arise in connection with oncomedical treatments in three ways: 1. acute and/or 2. chronic ways, as well as 3.
View Article and Find Full Text PDFBackground: Prolonged-release fampridine (PR-fampridine, 4-aminopyridine) increases walking speed in the timed 25-foot walk test (T25FW) in some patients (timed-walk responders) with multiple sclerosis (MS).
Objective: To explore the effects of PR-fampridine on different aspects of walking function and to identify associated gait modifications in subjects with MS.
Methods: In this prospective, randomized, placebo-controlled, double-blind, phase II study (FAMPKIN; clinicaltrials.
In patients with outlet obstruction, the contraction of the base is reduced compared to that of healthy individuals, while the contraction of the dome is not affected. Here, we investigated the cellular mechanisms that might be responsible for cholinergic effects blocking non-adrenergic non-cholinergic contractions in the base of the urinary bladder. Smooth muscle cells either from the base or from the dome of human urinary bladders were cultured to determine the contribution of cholinergic and purinergic mechanisms to their Ca2+ homeostasis.
View Article and Find Full Text PDFJ Laparoendosc Adv Surg Tech A
April 2008
The authors report a rare case of percutaneous endoscopic ureterolithotomy of 2 ureteral stones. Extracorporeal shock-wave lithotripsy (SWL) treatment of the renal stone was performed. The stone was crushed into 2 pieces, with 1 of them located in the upper part, and the other in the middle part of the ureter.
View Article and Find Full Text PDFThe authors developed a new, minimally invasive technique for the removal of impacted iuxtavesical ureteral stones, using nephroscope and a grasping forceps. They named this technique ostiolitholapaxy. The authors present their detailed technique and results.
View Article and Find Full Text PDFJ Laparoendosc Adv Surg Tech A
June 2007
Percutaneous endoscopic ureterolithotomy is not a well-known method for the treatment of impacted ureteral stones. The authors performed a retrospective study to compare the effectiveness of this procedure to ureteroscopy for the treatment of ureteral calculi. Impacted ureteral stones were removed in 93 patients by percutaneous endoscopic ureterolithotomy (Group 1).
View Article and Find Full Text PDFThe purpose of this study was to provide an account of the 5-year experience we have gained using holmium:yttrium-aluminium-garnet (Ho:YAG) lasertripsy in the treatment of ureteral stones. One-hundred thirty-seven transurethral ureterolithotripsies were performed in 131 patients. A Ho:YAG laser device, fibres with diameters of 360 and 550 mum, a video camera as well as semi-rigid and flexible ureterorenoscopes were used.
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