Global climate-driven trade-offs between the water retention and cooling benefits of urban greening.

Urban greening can potentially help mitigate heat-related mortality and flooding facing the >4 billion urban population worldwide. However, the geographical variation of the relative combined hydrological and thermal performance benefits of such interventions are unknown. Here we quantify globally, using a hydrological model, how climate-driven trade-offs exist between hydrological retention and cooling potential of urban greening such as green roofs and parks. Using a Budyko framework, we show that water retention generally increases with aridity in water-limited environments, while cooling potential favors energy-limited climates. Our models suggest that common urban greening strategies cannot yield high performance simultaneously for addressing both urban heat-island and urban flooding problems in most cities globally. Irrigation, if sustainable, may enhance cooling while maintaining retention performance in more arid locations. Increased precipitation variability with climate change may reduce performance of thinner green-infrastructure more quickly compared to greened areas with thicker soils and root systems. Our results provide a conceptual framework and first-order quantitative guide for urban development, renewal and policymaking.

A dusty veil shading Betelgeuse during its Great Dimming.

Red supergiants are the most common final evolutionary stage of stars that have initial masses between 8 and 35 times that of the Sun1. During this stage, which lasts roughly 100,000 years1, red supergiants experience substantial mass loss. However, the mechanism for this mass loss is unknown2. Mass loss may affect the evolutionary path, collapse and future supernova light curve3 of a red supergiant, and its ultimate fate as either a neutron star or a black hole4. From November 2019 to March 2020, Betelgeuse-the second-closest red supergiant to Earth (roughly 220 parsecs, or 724 light years, away)5,6-experienced a historic dimming of its visible brightness. Usually having an apparent magnitude between 0.1 and 1.0, its visual brightness decreased to 1.614 ± 0.008 magnitudes around 7-13 February 20207-an event referred to as Betelgeuse's Great Dimming. Here we report high-angular-resolution observations showing that the southern hemisphere of Betelgeuse was ten times darker than usual in the visible spectrum during its Great Dimming. Observations and modelling support a scenario in which a dust clump formed recently in the vicinity of the star, owing to a local temperature decrease in a cool patch that appeared on the photosphere. The directly imaged brightness variations of Betelgeuse evolved on a timescale of weeks. Our findings suggest that a component of mass loss from red supergiants8 is inhomogeneous, linked to a very contrasted and rapidly changing photosphere.

Blood Glutathione Peroxidase Activity in Patients with Osteoarthritis Treated with Oxicams.

PURPOSE: The main objective of this study was the comparison of the influence for three non-steroidal anti-inflammatory drugs (NSAIDs) belonging to the oxicam class, namely piroxicam and tenoxicam, as non-selective inhibitors of cyclooxygenase (COX), and meloxicam, a selective COX-2 inhibitor, on glutathione peroxidase (GPx) activity in patients with osteoarthritis of the knee. MATERIAL/METHODS: Thirty adult subjects clinically and radiographically diagnosed with knee osteoarthritis, who were not previously subjected to any treatment, were enrolled. They were divided in three groups, each with ten subjects. The serum levels of GPx were assessed at baseline and after twenty days of treatment. The first group received piroxicam at a dose of 20 mg orally daily, the second group was treated with tenoxicam at a dose of 20 mg orally daily, and in the third group meloxicam was administrated in a dose of 15 mg orally daily. RESULTS: After the treatment, it was observed an increase of the GPx activity in all groups. The group treated with meloxicam presented the highest rise in the GPx level (p = 0.052). CONCLUSIONS: The 20 days study concerning the effects of treatment with NSAIDs belonging to the oxicam class in subjects with knee osteoarthritis revealed that piroxicam, tenoxicam and meloxicam determined a slightly increase in the GPx activity, although this rise had no statistical significance.

Plant Growth Regulating Activity of Some N-Substituted Chloroacetylanilines.

PURPOSE: The synthesis and physico-chemical characterization of six N-substituted chloroacetylanilines and testing their plant growth regulating activity. MATERIAL/METHODS: The synthesis of the six N-substituted chloroacetylanilines was accomplished by condensation of N-substituted anilines, in an acidic medium, with chloroacetylchloride. Purified compounds obtained were physico-chemical characterized by elemental analysis and spectral analysis. Five different concentrations (0.1%, 0.5%, 0.75%, 1% and 5%) of the compounds solubilized in chloroform were used to analzyed their effects on the germination and mainly on the radicular elongation of wheat caryopses, Triticum aestivum subsp. aestivum (Poaceae), Dropia variety. RESULTS: The N-substituted chloroacetylanilines were solid, differently colored, with high melting temperatures and high yields. Their structure was confirmed both by elemental analysis and by the spectral methods (UV-Vis, FTIR, 1H-NMR, 13C-NMR, GC-MS). CONCLUSIONS: For the six analyzed compounds, at five different concentrations (0.1%, 0.5%, 0.75%, 1% and 5%), the experimental data obtained by the method of linear measurement, in the Triticum assay, showed the inhibition of mean radicular elongation compared with the reference.

Evaporative cooling of speleothem drip water.

This study describes the first use of concurrent high-precision temperature and drip rate monitoring to explore what controls the temperature of speleothem forming drip water. Two contrasting sites, one with fast transient and one with slow constant dripping, in a temperate semi-arid location (Wellington, NSW, Australia), exhibit drip water temperatures which deviate significantly from the cave air temperature. We confirm the hypothesis that evaporative cooling is the dominant, but so far unattributed, control causing significant disequilibrium between drip water and host rock/air temperatures. The amount of cooling is dependent on the drip rate, relative humidity and ventilation. Our results have implications for the interpretation of temperature-sensitive, speleothem climate proxies such as δ(18)O, cave microecology and the use of heat as a tracer in karst. Understanding the processes controlling the temperature of speleothem-forming cave drip waters is vital for assessing the reliability of such deposits as archives of climate change.

Portal venous gas detected by ultrasound differentiates surgical NEC from other acquired neonatal intestinal diseases.

BACKGROUND: The definite clinical diagnosis of acquired neonatal intestinal diseases (ANID) is a challenge, usually met by applying Bell's or, more recently, Gordon's classification. Both classifications incorporate radiological pneumatosis intestinalis (PI) as a cornerstone of the NEC diagnosis. However, PI may be absent or difficult to identify by abdominal X-ray. Portal venous gas detected by ultrasound (PVG-US) has been proposed as another characteristic of NEC, but its incidence in other entities of ANID remains unknown. OBJECTIVE: To determine whether PVG-US and Gordon's classification can help to differentiate between NEC and other ANID, especially SIP. METHODS: Retrospective analysis of the data of 83 infants, who underwent laparotomy for a clinical diagnosis of ANID was performed. The results of PVG-US and other markers of ANID were compared with the operative result, defined as the gold standard for diagnosis. RESULTS: The NEC diagnosis was confirmed in 28/83 infants and PVG-US was present in 23 (82%) of those patients prior to operation. PVG-US was detected in 2 patients without NEC (one volvulus, one SIP), resulting in an 82% sensitivity and a 96% specificity. The sensitivity and specificity of radiological PI for patients with NEC was lower (75 and 91%), but the combination of PVG-US and radiological PI increased the sensitivity for NEC detection to 89%. Gordon's classification had a sensitivity of 93% and a specificity of 92% for NEC diagnosis. CONCLUSION: Screening for PVG-US and Gordon's classification are valid tools to differentiate between NEC and other ANID including SIP. Although an effect of these proposed diagnostic tools on treatment regimen and operative management has yet to be verified, the improvement in diagnosing ANID is certainly valuable.

Evaluation of portal venous gas detected by ultrasound examination for diagnosis of necrotising enterocolitis.

BACKGROUND: Early diagnosis of necrotising enterocolitis (NEC) is difficult but essential for timely therapy. The diagnostic hallmarks and specific radiological signs for NEC are pneumatosis intestinalis (PI) and portal venous gas (PVG), but PVG in abdominal ultrasound (PVG-US) has been proposed as an effective tool in the diagnosis of NEC as well. OBJECTIVE: To prospectively assess the value of PVG-US for the diagnosis of NEC. METHODS: The study screened 352 neonates for PVG-US (n = 796 routine examinations) and performed 48 additional screenings in 34/352 neonates with suspected (stage I, n = 28) or definite NEC (stage > or =II, n = 20). Sensitivity and specificity of PVG-US for detection of NEC were computed by using NEC stage > or =II as the reference standard. RESULTS: PVG-US was only present in cases of suspected or definite NEC. The study observed PVG-US in 4/28 NEC stage I and in 9/20 NEC stage > or =II episodes corresponding to a 86% specificity and a 45% sensitivity for diagnosis of NEC stage > or =II. However, 7/20 patients with NEC stage > or =II showed intraoperative findings other than NEC and another 3/20 infants presented with radiologically unspecific intestinal dilatation. None of these 10 infants had detectable PVG-US. Thus, with application of specific radiological signs the sensitivity of PVG-US for diagnosis of NEC stage > or =II increased to 90%. CONCLUSION: Screening for PVG-US is a useful, easy and quick bedside test with a high specificity for NEC. Moreover, these results question the value of the Walsh criteria in the diagnosis of NEC.

The MiniACcor: constructive redesign of an implantable total artificial heart, initial laboratory testing and further steps.

The Aachen Total Artificial Heart (ACcor) has been under development at the Helmholtz Institute in Aachen over the last decade. It may serve as a bridge to transplant or as a long-term replacement of the natural heart. Based upon previous in vivo experiments with the ACcor total artificial heart, it was decided to optimize and redesign the pump unit. Smaller dimensions, passive filling and separability into three components were the three main design goals. The new design is called the MiniACcor, which is about 20% smaller than its predecessor, and weighs only 470 grams. Also its external driver/control unit was miniaturized and a new microcontroller was selected. To validate the design, it was extensively tested in laboratory mock loops. The MiniACcor was able to pump between 4.5 and 7 l/min at different pump rates against normal physiological pressures. Several requirements for the future compliance chamber and transcutaneous energy transmission (TET) system were also measured in the same mock loop. Further optimization and validation are being performed in cooperation with the Heart and Diabetes Centre North Rhine-Westphalia.

Antenatal ultrasonographic appearance of isolated fetal ascites. A case report of sinus urogenitalis.

BACKGROUND: Isolated fetal ascites can be caused by many heterogeneous disorders and is associated with a variety of conditions. Cloacal anomalies are rare abnormalities with a highly variable array of sonographic symptoms, which make them difficult to diagnose antenatally. We present a case with isolated fetal ascites without hydronephrosis caused by a cloacal malformation. CASE: A 28-year-old woman, gravida 2, para 1, was referred to our unit at 18 weeks gestation with a hyperdense structure in the fetal liver. Cordocentesis revealed a normal karyotype and negative viral titers. Isolated fetal ascites occurred for the first time at 23 weeks gestation. Serial ultrasounds showed progressive fetal ascites with no hydronephrosis at any time and no other malformations apart from the previously diagnosed hyperechogenic liver structure. After the insertion of an abdomino-amniotic shunt, a temporary reduction of the sonographically detectable ascites could be achieved. Cesarean delivery was necessary due to a pathological CTG at 33 weeks of gestation. The baby was born with a markedly distended abdomen. Postnatal radiologic examination showed two fistulae between the cloaca and the notedly dilated vagina and the rectum respectively. At the age of 3 months a vaginoplasty was performed, which involved creating a correctly positioned vaginal opening, reconstruction of the urethra and rectum as well as occlusion of the two fistulae. CONCLUSION: In view of the examinations, performed before and after delivery, it has to be assumed that fetal urine drained via the cloaca through the fallopian tubes into the abdomen. In contrast to usual appearance of cloacal malformations no hydronephrosis was detected and the kidney function was normal at all times. To our knowledge, this is the first published case of isolated fetal ascites without hydronephrosis caused by a cloacal malformation.

Movement analysis in the early detection of newborns at risk for developing spasticity due to infantile cerebral palsy.

In order to limit the consequences of infantile cerebral palsy (ICP), physiotherapy should start as early as possible. This requires that infants at risk are detected at the earliest age possible. Today, diagnosis is based on visual observation by physicians and as such is influenced by subjective impressions. Objective methods, quantifying the pathological deviation from normal spontaneous motor activity would be preferable as they, for example, allow an inter- and intra-individual comparison of movement. In this paper we have developed a methodology that allows the 3-dimensional acquisition of unconstrained movement in newborn babies, using a motion analysis system. From the recorded movement data we have extracted 53 quantitative parameters that describe the differences between healthy and affected participants. Considered individually, each of these parameters does not permit a conclusive statement to be made as to whether or not the patient is at risk. Cluster analysis based on Euclidian distances therefore has been used to find an optimal combination of eight parameters. The optimal combination has been subsequently applied to organize the participants' movement into preferably homogeneous classes labelled "healthy" or "at risk". Classification was performed utilising quadratic discriminant analysis. The methodology presented allows a reliable discrimination between healthy and affected participants. Overall detection rate reached 73%. This value is expected to rise with increasing patient and norm collective database size.

Upper trapezius muscle conduction velocity during fatigue in subjects with and without work-related muscular disorders: a non-invasive high spatial resolution approach.

The development of fatigue at the muscle fibre level can be assessed in terms of a decrease in conduction velocity (CV). The present study aimed to investigate if work-related muscular disorders in occupations characterised by static loads of long duration affect fatigue resistance in the painful muscle. A group of eight secretaries suffering from bilateral chronic muscle pain in the shoulder/neck region was compared to a group of healthy subjects. The upper trapezius muscle was studied under isometric contractions, holding the arm in the horizontal plane up to the endurance point. Changes in CV estimated at the motor unit level were investigated using a non-invasive high spatial resolution electromyographic (EMG) approach. In addition, the number of motor unit potentials per second (PPS), and the root mean square (RMS) of bipolar signals were assessed, and the results reported as the mean and standard error for each value. Subjects with work-related disorders showed less pronounced changes in CV with respect to healthy subjects. No differences between subjects with and without work-related disorders were encountered for the PPS and RMS. The present findings on CV indicate an increased fatigue-related recruitment of MUs in the painful muscle with respect to a healthy muscle. The fact that this recruitment is not reflected in the PPS and RMS estimates might be due to a fatigue-induced decrease in the firing rate and/or the de-recruitment of fatigued MUs. Furthermore, methodological limitations of the adopted method in the estimation of 'global' parameters such as the PPS and RMS have to be considered.

Comparison of the electromyographic activity in the upper trapezius and biceps brachii muscle in subjects with muscular disorders: a pilot study.

The aim of the present study was to investigate the extent to which work-related muscular disorders of the upper trapezius affect the activity of other pain-free muscles, in particular in the biceps brachii. Two groups of female subjects (age >43 years) participated in the study: seven affected subjects with self-reported disorders in the shoulder/neck region (cases) and nine healthy subjects (control group). Multi-channel electromyography (EMG) and force were recorded during maximum voluntary contractions (MVC) and during 6 min sustained contractions (at 30% MVC) of the upper trapezius and biceps brachii on the dominant side. From the EMG signals, the root mean square (RMS), median frequency (MDF) and single motor unit (MU) conduction velocity (CV) were estimated. From the force signal, the coefficient of variation was calculated. All data are presented as mean values and standard deviation. Differences between the cases and controls were found in the MVC force of the upper trapezius, which was lower in cases [253 (70) N] than in controls [357 (75) N], while the coefficient of variation of force during the sustained contraction was increased [cases 5.5 (2.2); controls 4.1 (1.9)]. The RMS (normalized to the RMS at MVC) during the 6 min sustained contractions was significantly lower in the cases than in the controls for both the upper trapezius and the biceps brachii. A tendency towards a smaller increase in the RMS with fatigue was only found in the trapezius muscle [slope: cases 6.5 (14.1) %/min, controls 10.2 (12.9) %/min]. No differences were found between the two subject groups with respect to the MDF and single MU CV in both muscles. While the lower RMS for the trapezius muscles of the cases may reflect changes at the local level, as well as in motor control, the lower biceps activity indicates a change in the central control strategies of the primarily unaffected muscle. Indications for a changed fatigability of the muscle were only found in the trapezius.

Design and in vitro performance of a novel bileaflet mechanical heart valve prosthesis.

Design and in vitro performance of a novel bileaflet mechanical heart valve prosthesis are presented. The novel heart valve exhibits three main design characteristics: (i) The leaflets form a Venturi passage in open position. Thus, a beneficial pressure distribution is obtained and the leaflets are stabilised in opened position. (ii) The orifice inlet is nozzle-shaped. Flow is convectively accelerated and flow separation at the orifice inlet is avoided. (iii) The hinge design facilitates an additional axial movement of the leaflets and leads to a self cleaning effect and enhances washout of the hinges. The design of the leaflet hinges is of main importance for the functional reliability and durability of mechanical heart valves. After manufacturing first prototypes from titanium and polymeric materials the hydrodynamic performance was evaluated according to ISO 5840 and FDA guidelines. Hydrodynamic performance is comparable with the results of commonly available bileaflet mechanical heart valve prostheses. Initial durability tests showed suitable material couples for further long term studies.

Estimation of the muscle fibre semi-length under varying joint positions on the basis of non-invasively extracted motor unit action potentials.

Changes in muscle fibre length and surface electrode position with respect to the muscle fibres affect the amplitude and frequency characteristics of surface electromyography (SEMG) in different ways. Knowledge of changes in muscle fibre length would help towards a better interpretation of the signals. The possibility of estimating the length through SEMG during voluntary contractions was checked in this study. The fibres' semi-length was estimated from the product of the conduction velocity and conduction time during which the wave of excitation propagated from the end-plate region to the ends of the fibres. Short (10 s), moderate (30% of maximum voluntary contraction) isometric contractions were performed by 10 subjects at different elbow joint angles (80-140 degrees in steps of 20 degrees ). Monopolar signals were detected non-invasively, using a two-dimensional electrode array. High spatial resolution EMG and a decomposition technique were utilised to extract single motor unit activities for triggered averaging and to estimate conduction velocity. A significant increase with joint angle was found in conduction time and estimated fibre semi-length. Changes in conduction velocity with joint angle were found to be not significant. The methodology described allows the relative changes in fibres' semi-length to be estimated from SEMG data.

From cell to movement: to what answers does EMG really contribute?

This paper aims to address some of the possibilities and limitations of EMG technologies available to date. Considerable progress has been achieved in this field during the last 30 years and EMG signals can be easily obtained on different levels beginning at the cell membrane and ending with the global EMG associated with the movement itself. Different aspects from cell to movement have been considered in this paper. Highly selective needle EMG for the detection of the processes at the membrane is discussed as well as high spatial resolution EMG which gives non-invasive access to the acquisition of the single motor unit activity. On the highest level of muscles, an expert system is introduced as a novel approach to support the interpretation of muscular co-ordination as detected by conventional surface EMG. While there is a high potential in the newly developed EMG methodologies, it is a big challenge to utilize these methodologies in order to obtain detailed, repeatable, reliable--and meaningful--results. However, the risk of over- and misinterpretation has to be carefully considered. In this paper, this risk is exemplified in situations dealing with muscle fatigue, conduction velocity and cross-talk. Despite all the new possibilities available, the authors recommend that EMG with its inherent strengths and limitations should still be diligently, but carefully, used.

Influence of muscle fibre shortening on estimates of conduction velocity and spectral frequencies from surface electromyographic signals.

The study of surface electromyographic (EMG) signals under dynamic contractions is becoming increasingly important. However, knowledge of the methodological issues that may affect such analysis is still limited. The aim of the study was to analyse the effect of fibre shortening on estimates of conduction velocity (CV) and mean power spectral frequency (MNF) from surface EMG signals. Single fibre action potentials were simulated, as detected by commonly used spatial filters, for different fibre lengths. No physiological modifications were included with changes in fibre length, and thus only geometrical artifacts related to fibre shortening were investigated. The simulation results showed that the dependence of CV and MNF on fibre shortening is affected by the fibre location, electrode position and the spatial filter applied. With shortening of up to 50% for a fibre of 50 mm semi-length, the variations in CV and MNF estimates with shortening in bipolar recordings were 0.5% (CV) and 0.7% (MNF) for superficial fibres, and 3.6% and 5.1% for deeper fibres. Using the longitudinal double differential filter, under the same conditions, the percent variation was 0% and 0.2%, and 24.7% and 15.8%, respectively. The main conclusions were, first, muscle fibre shortening can significantly affect estimates of CV and MNF, especially for short fibre lengths. However, for long (semi-length >50 mm) and superficial fibres, this effect is limited for shortenings of up to 50% of the initial fibre length. Secondly, CV and MNF are almost equally affected by changes in muscle length; and, thirdly, sensitivity to fibre shortening depends on the spatial filter applied for signal detection.

Experimental muscle pain increases trapezius muscle activity during sustained isometric contractions of arm muscles.

OBJECTIVE: In the present study, the influence of experimental muscle pain on muscle co-ordination and fatigue development during sustained isometric elbow flexion was investigated. METHODS: Conventional surface electromyography (EMG) was recorded from the biceps brachii, brachioradialis, deltoideus and trapezius muscle during isometric elbow flexion at 40% maximum force. Single motor unit (MU) conduction velocity in the biceps brachii was assessed using a high spatial resolution surface EMG technique. Measurements were performed on 15 healthy subjects before, during and after (1) injection of hypertonic (pain condition) and (2) isotonic saline (control) into the biceps brachii. The pain intensity was assessed on a 10 cm visual analogue scale. RESULTS: The experimental results showed in both experimental sessions a fatigue-related increase of the root mean square value of EMG (222+/-164% of the baseline), and a decrease of the median frequency (118+/-16% of the baseline) in all investigated muscles. A maximum pain level of in average 3.2 cm on the visual analogue scale was reached after injection of hypertonic saline during contraction. Differences between painful and control condition were seen in an increased trapezius activity (230+/-141%) during pain. The global EMG activity of the brachioradialis and biceps brachii was unaffected by experimental muscle pain in line with unaffected single MU conduction velocity in the biceps brachii. Differences in endurance time (mean 89.3 and 102.3 s, pain and control, respectively) were not significant. CONCLUSIONS/SIGNIFICANCE: The findings suggest that upper extremity pain could be a possible source for overloading the trapezius muscle and as such is an important factor in occupational settings.

Single motor unit analysis from spatially filtered surface electromyogram signals. Part I: spatial selectivity.

The aim of the study was to compare experimentally, on the basis of single motor unit (MU) activities, the selectivity of different spatial filters commonly used to detect surface electromyogram (EMG) signals. Surface EMG signals were recorded from the biceps brachii and the upper trapezius muscle of five subjects using a two-dimensional (2D) electrode array consisting of 16 pin electrodes. The subjects performed isometric contractions at different elbow angles and shoulder abduction and flexion. The same monopolar surface EMG signals were filtered using longitudinal single and double differential, transverse single and double differential and normal double differential filters. From the single MU action potentials, extracted by automatic EMG decomposition, indexes of transverse (perpendicular with respect to the fibre direction) and longitudinal (along the fibre direction) selectivity were computed. The number of detected MUs was 46 for the upper trapezius, with the arms held in the sagittal plane, and 52 when the arms were held in the frontal plane; 85 MUs were identified from the biceps brachii contractions. The results showed that transverse selectivity was significantly higher for the 2D and transverse one-dimensional (1D) filters with respect to the 1D longitudinal filters, whereas longitudinal selectivity was higher (i.e. MU action potentials were shorter) for the 2D filter and the longitudinal double differential filter. In particular, the relative attenuation of potential amplitude moving 5 mm from the source was, on average (for the two muscles), 16.5% for the least selective filter in the transverse direction (longitudinal single differential) and 35.7% for the most selective one in the same direction (transverse double differential). The MU action potential duration was, on average, 13.8 ms for the most selective filter in the longitudinal direction (longitudinal double differential) and 18.7 ms for the least selective one (transverse double differential). The normal double differential filter resulted in spatial selectivity indexes that ware not statistically different in the two directions from those of the best filters in each direction.

Single motor unit analysis from spatially filtered surface electromyogram signals. Part 2: conduction velocity estimation.

The aim of the study was to compare experimentally conduction velocity (CV) estimates obtained with different estimation methods based on surface electromyogram (EMG) signals detected using five spatial filters. The filters investigated were the longitudinal single and double differential, transverse single and double differential, and normal double differential. The same surface EMG signals detected as described in Part 1 were used in this work. CV was estimated with four commonly used delay estimation techniques, i.e. from the distance between the peak values of two waveforms (with and without polynomial interpolation around the peak), and by the maximum likelihood estimate (MLE) based on two or more surface EMG channels. The average standard deviation of CV estimation (for all the MUs and the two muscles together) was 0.61 m s(-1) and 0.79 m s(-1) for the peak method, with and without interpolation, respectively, and 0.50 m s(-1) and 0.31 m s(-1) for the MLE method, from two and more surface EMG channels, respectively. Moreover, the mean of CV estimates varied by as much as 1 m s(-1) depending on the spatial filter used and the method adopted for CV estimation. Considering the dependence on the spatial filter only, the average (over all estimation methods) CV estimates obtained with the five spatial filters were 4.32 m s(-1) (normal double differential), 4.23 m s(-1) (longitudinal double differential), 4.61 m s(-1) (transverse double differential), 4.64 m s(-1) (transverse single differential) and 4.03 m s(-1) (longitudinal single differential). It was concluded that the comparison of single MU CV values obtained in different studies is critical if different spatial filters and processing techniques are used for their estimation. Higher estimates of CV were attributed to a smaller reduction in non-travelling signal components and thus were assumed to be positively biased.

[Arm motion analysis: a new method and its clinical application]. / 3D-Analyse der Armbewegung: eine neue Methode und erste klinische Anwendung.

AIM: An investigation into the objective criteria of shoulder mobility possesses special meaning for diagnostic documentation, the evaluation of therapy and the effects of rehabilitation in the treatment of diseases of the shoulder. In order to ascertain the criteria which characterise shoulder mobility, it is necessary to have a tool available that is objective, comparable and allows the complexity, variability and range of motion to be recorded. Motion analysis represents one such standard procedure used to measure joint movement. METHOD: Accordingly, a marker- based motion analysis of the wrist and elbow, a marker-based three-dimensional motion analysis system for the upper extremities was developed. We evaluated 10 healthy subjects without shoulder conditions and 8 patients with impingement syndrome (7 operative, 1 conservative therapy). RESULTS: The healthy subjects revealed a reproducible motion curve for the specific motion tested. The curves were defined as the normal standard and we used them for comparative purposes. In the treatment group, an improvement of the 3D range of motion could be documented for the affected shoulder following rehabilitation. CONCLUSION: It can be stated that this newly developed marker-based procedure for the three-dimensional motion analysis is suitable for recording complex unconstrained movements. This was found to be more relevant for the assessment of the ability of patients to manage the physical demands of daily living than traditional clinical tests. Furthermore, the information gained from motion analysis of the upper extremities will play a valuable role in the future for quality control during diagnosis and treatment, as well as for the design of shoulder rehabilitation programs.