Probing magnetic order and disorder in the one-dimensional molecular spin chains CuF2(pyz) and [Ln(hfac)3(boaDTDA)] n (Ln = Sm, La) using implanted muons.

We present the results of muon-spin relaxation ([Formula: see text]SR) measurements on antiferromagnetic and ferromagnetic spin chains. In antiferromagnetic CuF2(pyz) we identify a transition to long range magnetic order taking place at [Formula: see text] K, allowing us to estimate a ratio with the intrachain exchange of [Formula: see text] and the ratio of interchain to intrachain exchange coupling as [Formula: see text]. The ferromagnetic chain [Sm(hfac)3(boaDTDA)] n undergoes an ordering transition at [Formula: see text] K, seen via a broad freezing of dynamic fluctuations on the muon (microsecond) timescale and implying [Formula: see text]. The ordered radical moment continues to fluctuate on this timescale down to 0.3 K, while the Sm moments remain disordered. In contrast, the radical spins in [La(hfac)3(boaDTDA)] n remain magnetically disordered down to T = 0.1 K suggesting [Formula: see text].

[German Translation and Linguistic Validation of the Multidimensional Dyspnea Profile (MDP)]. / Deutsche Übersetzung und sprachliche Validierung des multidimensionalen Dyspnoe-Profils (MDP).

BACKGROUND: Dyspnea is characterized as a subjective perception of breathing discomfort. This includes distinct sensory qualities with distinct intensities. The detection and quantization of these quality distinctions can be quite difficult. As yet, there is no instrument in German covering the multidimensionality of dyspnea. Banzett et al. developed the Multidimensional Dyspnea Profile (MDP) in 2015 to meet and to understand the multidimensional nature of dyspnea, disease span and at varying times or situations. METHODS: This paper presents the German translation of the MDP. The MAPI Research Trust has developed the German version in accordance with the recognized guidelines for intercultural adaption of patient reported outcomes. That included a linguistic validation in patients with this condition. RESULTS: The Multidimensional Dyspnea Profile measures the intensity of dyspneic breathing discomforts. It tests five sensory qualities that describe the patient's dyspnea in its respective intensity. Additionally, it includes five potential reactions. The MDP is designed to refer to a specific event in time. CONCLUSION: The authors made the instrument freely available for academic use in English language. In addition, the German version is finally available and can be used in both everyday clinical practice and laboratory research.

[Unilateral reduction of lung volume by application of intrabronchial valves on patients selected after endoscopic collateral ventilation assessment]. / Unilaterale Lungenvolumenreduktion mit intrabronchialen Ventilen nach Selektion mittels endoskopischer Kollateralventilationsmessung.

BACKGROUND: Endoscopic collateral ventilation assessment (ECVA) can be used to select patients suffering from emphysema for application of valves to achieve a reduction of lung volume. The objective is to obtain a post-operatively minimal clinically important improvement of the selected patient's physical capacity. METHODS: Patients with severe chronic obstructive pulmonary disease (COPD) underwent examination for a possible reduction of lung volume. Those selected got ECVA. Patients whose collateral resistance (Rcoll) increased to Rcoll > 10 cm H2O/(mL/s) within a measurement duration of up to 300 s, were submitted to unilateral lobar application of intrabronchial valves (IBV). Differences in residual volume (RV) as well as distances in 6 minute walk tests (6MWT) between the time after application of valves (TX) and that before (T1) were calculated (TX minus T1). RESULTS: Of a tested 310 emphysema patients, 17 met criteria allowing ECVA; 10 of 17 proved eligible for valve application. After 312 ±â€Š170 days (TX - T1) the increase in walking distance was 44 ±â€Š89.7 m; 7 of 10 patients achieved clinically relevant improvements (> 25 m). Differences in RV proved to correlate with differences in walking distances, but not yet with differences in measurement duration in ECVA. CONCLUSIONS: Only a small portion of patients with progressive emphysema of the lung seem suitable for endoscopic reduction of lung volume by application of valves. Unilateral lobar application of IBV can result in durable, clinically relevant improvements of the patient's physical capacity. ECVA measurements should take a minimum of 300 s.

[Telemonitoring of bike exercise training in patients with obstructive sleep apnoea]. / Telemonitoring von Fahrrad-Heimtraining bei Patienten mit obstruktiver Schlafapnoe.

BACKGROUND: Patients with obstructive sleep apnoea (OSA) suffer from daytime sleepiness, cognitive disorders and are at increased risk of cardiovascular diseases. In addition to continuous positive airway pressure (CPAP), major lifestyle changes to increase physical activity contribute to risk reduction. The daily training duration should be at least 20 minutes to achieve a relevant effect. In addition to exercise training in groups, home training is useful. However, sufficiently intensive training is often not performed because of unavailable feedback (monitoring). It is not clear yet how many patients accept a bicycle home training and to what extent they meet the specified training time. METHOD: Of the 152 consecutive OSA patients surveyed, 74 (48.7 %) agreed to a 4-week home exercise bike training. After exclusion of 51 patients, 17 for logistical reasons, and 34 because of severe comorbidities, 23 patients remained (age 51.0 +/- 9.3 years, BMI 33.7 +/- 4.2, ESS score 10.4 +/- 6.7, AHI 33.8 +/- 24.0). The daily duration of training at the ventilatory threshold (VT1) was recorded and transmitted by a wireless module (Cinterion) via Internet to a doctor or instructor. RESULTS: The patients exercised during 27.3 +/- 2.9 days. 19 of the 23 patients (83 %) accomplished the training period of > 20 minutes per day. In 4 patients (17 %) the training time was well below this target level with 5.9 +/- 2.3 min. The average training time of all patients was 24.4 +/- 9.0 min. CONCLUSION: About 50 % of the OSA patients are interested in a regular physical exercise bike training with telemonitoring, and are performing it quite constantly. The described method of telemonitoring provides a simple and, compared to group training cost-effective way to reduce cardiovascular risk in OSA.

Charged and metallic molecular monolayers through surface-induced aromatic stabilization.

Large π-conjugated molecules, when in contact with a metal surface, usually retain a finite electronic gap and, in this sense, stay semiconducting. In some cases, however, the metallic character of the underlying substrate is seen to extend onto the first molecular layer. Here, we develop a chemical rationale for this intriguing phenomenon. In many reported instances, we find that the conjugation length of the organic semiconductors increases significantly through the bonding of specific substituents to the metal surface and through the concomitant rehybridization of the entire backbone structure. The molecules at the interface are thus converted into different chemical species with a strongly reduced electronic gap. This mechanism of surface-induced aromatic stabilization helps molecules to overcome competing phenomena that tend to keep the metal Fermi level between their frontier orbitals. Our findings aid in the design of stable precursors for metallic molecular monolayers, and thus enable new routes for the chemical engineering of metal surfaces.

Reversible electron-induced cis-trans isomerization mediated by intermolecular interactions.

Reversible isomerization processes are rarely found when organic molecular switches are adsorbed on metal surfaces. One obstacle is the large energy difference of the isomeric forms, since usually the most planar conformer has the largest adsorption energy. In the example of an imine derivative, we show a strategy for also stabilizing the non-planar isomer by intermolecular bonding to its neighbors. Tunneling electrons from the tip of a scanning tunneling microscope can then be used to induce reversible switching between the trans and cis-like state. Supported by model force-field calculations, we illustrate that the most probable cause of the enhanced stability of the three-dimensional cis state at specific adsorption sites is the electrostatic interaction with N sites of the neighboring molecule.

Enhanced charge transfer in a monolayer of the organic charge transfer complex TTF-TNAP on Au(111).

Electronic doping is a key concept for tuning the properties of organic materials. In bulk structures, the charge transfer between donor and acceptor is mainly given by the respective ionization potential and electron affinity. In contrast, monolayers of charge transfer complexes in contact with a metal are affected by an intriguing interplay of hybridization and screening at the metallic interface, determining the resulting charge state. Using scanning tunneling microscopy and spectroscopy, we characterize the electronic properties of the organic acceptor molecule 11,11,12,12-tetracyanonaptho-2,6-quinodimethane (TNAP) adsorbed on a Au(111) surface. The ordered islands remain in a weakly physisorbed state with no charge transfer interaction with the substrate. When the electron donor tetrathiafulvalene (TTF) is added, ordered arrays of alternating TNAP and TTF rows are assembled. In these structures, we find the lowest unoccupied molecular orbital (LUMO) of the free TNAP molecule shifted well below the Fermi level of the substrate. The TNAP is thus charged with more than one electron.

Gating the charge state of single molecules by local electric fields.

The electron-acceptor molecule TCNQ is found in either of two distinct integer charge states when embedded into a monolayer of a charge transfer complex on a gold surface. Scanning tunneling spectroscopy measurements identify these states through the presence or absence of a zero-bias Kondo resonance. Increasing the (tip-induced) electric field allows us to reversibly induce the oxidation or reduction of TCNQ species from their anionic or neutral ground state, respectively. We show that the different ground states arise from slight variations in the underlying surface potential, pictured here as the gate of a three-terminal device.

[Detection of daytime sleepiness using Epworth Sleepiness Scale and a 3-item questionnaire in obstructive sleep apnea]. / Erfassung der Tagesschläfrigkeit mittels Epworth-Schläfrigkeits-Skala und einem 3-Item-Fragebogen bei obstruktiver Schlafapnoe.

INTRODUCTION: The Epworth Sleepiness Scale (ESS) describes the likelihood of falling asleep in 8 specific situations. Pathological sleepiness (TS) of patients with obstructive sleep apnea (OSA) is most often diagnosed with an ESS score≥11 (TS-ESS). In an epidemiological study on the prevalence of sleep apnea syndrome (OSAS), only three questions with yes-no answers were used for the characterization of pathological daytime sleepiness (TS-Young): Due to the different construction of the ESS and the Young's questionnaire, we asked whether with the combination of the two questionnaires a larger number of patients with OSA and TS compared to the ESS can be identified. In addition, we examined the sleepiness questionnaires (FB) using objective vigilance in defined groups of OSA patients. METHODS: Using PSG 328 OSA patients with an AHI≥5 were identified. Vigilance was examined using the computer program CARDA. RESULTS: With both FB the same percentage of patients with AHI>5 with pathological sleepiness was found (48 %). By combining both FB (TS-comb), the number of patients increased from 158 (48.2 %) to 195 (59.5 %) significantly. The combination showed a significantly higher percentage with additional 37 (11.3 %) patients in comparison to the TS-ESS alone. Combining both FB, an increase of TS resulted in patients with below-average number of errors in the vigilance test (n=192) from 23.2 % to 31.4 % of these cases (p<0.001). CONCLUSIONS: As a single test both questionnaires can be used to detect daytime sleepiness with equal incidence. Combining both questionnaires a higher percentage of daytime sleepiness can be found in comparison to the ESS-questionnaire alone especially in patients without disturbance of vigilance.

Cryobiopsy increases the diagnostic yield of endobronchial biopsy: a multicentre trial.

Forceps, brushes or needles are currently the standard tools used during flexible bronchoscopy when diagnosing endobronchial malignancies. The new biopsy technique of cryobiopsy appears to provide better diagnostic samples. The aim of this study was to evaluate cryobiopsy over conventional endobronchial sampling. A total of 600 patients in eight centres with suspected endobronchial tumours were included in a prospective, randomised, single-blinded multicentre study. Patients were randomised to either sampling using forceps or the cryoprobe. After obtaining biopsy samples, a blinded histological evaluation was performed. According to the definitive clinical diagnosis, the diagnostic yield for malignancy was evaluated by a Chi-squared test. A total of 593 patients were randomised, of whom 563 had a final diagnosis of cancer. 281 patients were randomised to receive endobronchial biopsies using forceps and 282 had biopsies performed using a flexible cryoprobe. A definitive diagnosis was achieved in 85.1% of patients randomised to conventional forceps biopsy and 95.0% of patients who underwent cryobiopsy (p<0.001). Importantly, there was no difference in the incidence of significant bleeding. Endobronchial cryobiopsy is a safe technique with superior diagnostic yield in comparison with conventional forceps biopsy.

Ferromagnetic coupling of mononuclear Fe centers in a self-assembled metal-organic network on Au(111).

The magnetic state and magnetic coupling of individual atoms in nanoscale structures relies on a delicate balance between different interactions with the atomic-scale surroundings. Using scanning tunneling microscopy, we resolve the self-assembled formation of highly ordered bilayer structures of Fe atoms and organic linker molecules (T4PT) when deposited on a Au(111) surface. The Fe atoms are encaged in a three-dimensional coordination motif by three T4PT molecules in the surface plane and an additional T4PT unit on top. Within this crystal field, the Fe atoms retain a magnetic ground state with easy-axis anisotropy, as evidenced by x-ray absorption spectroscopy and x-ray magnetic circular dichroism. The magnetization curves reveal the existence of ferromagnetic coupling between the Fe centers.

Competition of superconducting phenomena and Kondo screening at the nanoscale.

Magnetic and superconducting interactions couple electrons together to form complex states of matter. We show that, at the atomic scale, both types of interactions can coexist and compete to influence the ground state of a localized magnetic moment. Local spectroscopy at 4.5 kelvin shows that the spin-1 system formed by manganese-phthalocyanine (MnPc) adsorbed on Pb(111) can lie in two different magnetic ground states. These are determined by the balance between Kondo screening and superconducting pair-breaking interactions. Both ground states alternate at nanometer length scales to form a Moiré-like superstructure. The quantum phase transition connecting the two (singlet and doublet) ground states is thus tuned by small changes in the molecule-lead interaction.

Site-Dependent Coordination Bonding in Self-Assembled Metal-Organic Networks.

The combination of organic linkers with metal atoms on top of inorganic substrates offers promising perspectives for functional electronic and magnetic nanoscale devices. Typically, coordination bonds between electron-rich end groups and transition-metal atoms lead to the self-assembly of metal-organic nanostructures, whose shape and electronic and magnetic properties crucially depend on the type of ligand. Here, we report on the site-selective bonding properties of Co atoms to the dichotomic dicyanoazobenzene molecule with its carbonitrile and diazo N-based moieties as possible ligands. Using low-temperature scanning tunneling microscopy (STM) and spectroscopy measurements, we resolve the formation of self-assembled metal-organic motifs. Cobalt atoms exhibit a clear spectroscopic fingerprint dependent on the different coordination site, which is further used to map their position, otherwise not clearly visible in the topographic STM images. Density functional theory corroborates the observed bonding patterns and evidences their coordinative nature.

[Use of cryoextraction in different types of airway obstruction]. / Kryoextraktion bei unterschiedlichen Formen einer Atemwegsobstruktion: Vier exemplarische Fälle.

With the development of mechanically stable cryoprobes, direct endoscopic removal of tissue from the bronchial system with cryotherapy is now possible. Tissue is frozen to the tip of the probe and removed by pulling on the probe together with the fiberscope. This procedure, also referred to as cryoextraction, additionally provides good quality biopsy specimens for histopathological examination. We report here on four patients with different forms of bronchial obstruction, in whom cryoextraction was performed for rapid recanalization. In addition to the immediate effect, the procedure has few complications and is cost-effective. Indications were mucoid impaction, foreign body aspiration, removal of suprastomal granulation tissue prior to decannulation after prolonged mechanical ventilation, and obstruction of the trachea and the main bronchi by a carcinosarcoma. In the latter case, the diagnosis was additionally based on a specimen obtained by cryobiopsy.

[Heated humidification during CPAP with and without tube insulation]. / Warmluftbefeuchtung unter CPAP mit und ohne Schlauchisolation.

BACKGROUND: Patients with obstructive sleep apnoea syndrome (OSAS) under continuous positive pressure (CPAP) often complain about drying-up of the throat and nasal mucosa. In many cases the problem can be eliminated with a heated humidifier (WLB). Especially in a cold environment condensation forming on cooling of the air in the tube and the mask can be observed. To avoid this, some patients use an insulating tube covering. We investigated the effect of temperature (T) and relative humidity (rH) of the environment, the ventilation pressure, mask leaks, insulation of tubing on the T and rH% of the delivered air at the end of the tube or in the mask in OSAS patients. METHOD: All measurements were performed with a conventional WLB (S8, Resmed Fa) and a temperature and humidity sensor (Fa Testo, Lenzkirch). PATIENTS: 8 patients with OSAS were examined during the day at a room temperature of 16.4 degrees C. RESULTS: The temperature at the outlet of the WLB increased with a higher ambient temperature. Through isolation with a hose cover the temperature drop in the tube was reduced by 2.3 degrees C. By tube insulation a mean increase in temperature between 1.6 and 1.0 C during normal breathing in dependence on the leakage flow in the mask was found. CONCLUSIONS: Due to additional insulation with a tube cover the mask temperature can be increased, albeit slightly, and the formation of condensation is reduced.

[Effects of a breath-triggered modulation of positive airway pressure ventilation on the AHI from patients with obstructive sleep apnoea]. / Effekte einer Atemzyklus-gesteuerten Druckmodulation (Flexline) auf den AHI bei Uberdrucktherapie von Patienten mit einem OSAS.

BACKGROUND: Positive airway pressure (CPAP) is the treatment of choice for patients with obstructive sleep apnoea syndrome (OSAS). Especially in relation to side effects, it is not clear whether it is better to administer a constant positive pressure during the respiratory cycle or to vary it while breathing. The Flexline maybe improves patients' adherence by increasing the pressure in the early inspiration and lowering it in early expiration. METHODS: The pressure characteristics of the Flexline were examined in healthy persons. Patients with OSAS were titrated with CPAP or with the Flexline in random order under PSG control in the sleep laboratory. The apnoea/hypopnoea index (AHI) per pressure level was determined. PATIENTS: 20 patients with the new diagnosis of OSAS, first time treated with CPAP (age 56.6 +/- 11.5 years, BMI 28.4 +/- 3.2 kg/m (2), AHI 44.1 +/- 18.7, SO2 min 77.7 +/- 8.4 % and ESS 8.6 +/- 5.1). RESULTS: Constant CPAP and the mean pressure in the modus Flexline are similar. The differences in pressure between inspiration and expiration in the Flexline are dependent on the breathing frequency and the primarily chosen pressure level. Reduction of upper airway obstructions is similar with both types of therapy (AHI: CPAP: 9.1 +/- 7.4, Flexline: 9.1 +/- 7.4) without influencing sleep quality (arousal index: CPAP: 21.7 +/- 8.4, Flexline: 20.1 +/- 9.8). CONCLUSIONS: The Flexline is equally efficient as CPAP in the treatment of OSAS.

[Telemonitoring of arm ergometric training in COPD patients. A pilot study]. / Telemonitoring von Armergometer-Training bei COPD-Patienten. Eine Pilotstudie.

INTRODUCTION: Regular moderate physical activity in COPD reduces morbidity and improves life expectancy. Many programmes often fail after rehabilitation because regular training at home, possibly caused by a lack of motivation, is not maintained, the performance parameters then decline to the prerehabilitation levels. For cost reasons, a simple procedure is required to measure the training times in the home environment with a daily transmission of telemetric data so that, in the case of decline, advice and assistance can be provided. QUESTIONS: How long is the actual daily training time monitored by telemetry of COPD patients if a target of 20 minutes per day is prescribed by the doctor? Is there a correlation between physical activity at home and the training period? METHOD: We used a device for training the upper extremities with a GSM data transmission module for the transfer of the training times. The physical activity before an exacerbation of COPD and the willingness to modify the training behaviour were determined by questionnaires. 13 patients with COPD (age 69 +/- 9 years, FEV1 48.6 +/- 23.9 %) were investigated prospectively for 6 days under stationary conditions. RESULTS: The mean training period (target 20 min/day) was 16.1 +/- 11.7 min/day. The frequency of physical activity per week correlated with the daily ergometry training period in the clinic (r = 0.59). CONCLUSION: Training supervised by telemonitoring represents a useful way to objectively obtain training times. Ergometric training in combination with online transmission (telemetric monitoring) and regular phone calls could be an inexpensive method to increase physical activity.

[Exercise testing by spiroergometry in a patient with sarcoidosis stage II. An unusual combination of functional impairments]. / Spiroergometrie bei einem Patienten mit Sarkoidose II. Eine aussergewöhnliche Kombination von Funktionsstörungen.

Sarcoidosis is a multisystem disease of unknown origin characterised by epitheloid cell granulomas in the lung and many other organs. The measurement of the alveolo-arterial O(2)-gradient (AaDO(2)) during exercise is the most sensitive method to detect the involvement of the lung with impairment of gas exchange. The method is suitable for follow-up observations to make the indication for a steroid therapy in the case of deterioration. In this case presentation using the 9-panel display proposed by Wasserman we diagnosed besides a slight impairment of the gas exchange a cardiocirculatory dysfunction with a reduction of the oxygen pulse and a reduced minute ventilation with a decrease of the alveolar ventilation. The hypoventilation could be explained by a weakness of the respiratory muscles or a reduction of the central respiratory drive. The functional disturbances could be diagnosed by spiroergometry without expensive or invasive methods. The findings should be examined more specifically with regard to therapeutic consequences.