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Purpose: This article investigates the qualities and thermal effects of a novel electrosurgical device (PT) which has been designed by ERBE Elektromedizin GmbH, Germany, for the preparation of critical locations such as in skin-sparing or nipple-sparing techniques and compares it to a standard device (SD) in a porcine ex vivo breast model using an heat map generated by infrared thermography.Methods: In total, 42 abdominal wall specimens of porcine tissue consisting of the skin and the underlying subcutaneous and muscle layer were alternately dissected using one of the devices and pre-settings. During the preparation with the two devices, the epicutaneous temperature was measured by an infrared camera (VarioCam, Jenoptik, Germany) and the maximum temperature as well as the slope of the temperature rise was analysed.Results: The use of PT shows significantly lower values for [Formula: see text] compared to SD. This effect was independent from the chosen mode. Using the same instrument in different modes, the use of AutoCut mode showed a significant reduction of [Formula: see text] at all indicated time points (SD: p < 0.0001 and PT: p < 0.0001). In summary, the combination of AutoCut + PT showed the lowest rise in temperature, whereas the combination of DryCut + SD led to the highest rise in temperature. The temperature difference between these two settings was 13.84 °C, which means a possible temperature reduction of 67% can be achieved by the right choice of device and its tailored mode.Conclusions: The novel PT shows a significant reduction in epicutaneous temperature and a significant reduction of the slope of temperature rise most probably by a more focused application of energy compared to SD. [ABSTRACT FROM AUTHOR]

Quantum magnets have occupied the fertile ground between many-body theory and low-temperature experiments on real materials since the early days of quantum mechanics. However, our understanding of even deceptively simple systems of interacting spin-1/2 particles is far from complete. The quantum square-lattice Heisenberg antiferromagnet, for example, exhibits a striking anomaly of hitherto unknown origin in its magnetic excitation spectrum. This quantum effect manifests itself for excitations propagating with the specific wavevector (π, 0). We use polarized neutron spectroscopy to fully characterize the magnetic fluctuations in the metal-organic compound Cu(DCOO)2⋅4D2O, a known realization of the quantum square-lattice Heisenberg antiferromagnet model. Our experiments reveal an isotropic excitation continuum at the anomaly, which we analyse theoretically using Gutzwiller-projected trial wavefunctions. The excitation continuum is accounted for by the existence of spatially extended pairs of fractional S = 1/2 quasiparticles, 2D analogues of 1D spinons. Away from the anomalous wavevector, these fractional excitations are bound and form conventional magnons. Our results establish the existence of fractional quasiparticles in the high-energy spectrum of a quasi-two-dimensional antiferromagnet, even in the absence of frustration. [ABSTRACT FROM AUTHOR]

The need for both high electrical conductivity and low thermal conductivity creates a design conflict for thermoelectric systems, leading to the consideration of materials with complicated crystal structures. Rattling of ions in cages results in low thermal conductivity, but understanding the mechanism through studies of the phonon dispersion using momentum-resolved spectroscopy is made difficult by the complexity of the unit cells. We have performed inelastic X-ray and neutron scattering experiments that are in remarkable agreement with our first-principles density-functional calculations of the phonon dispersion for thermoelectric Na0.8CoO2, which has a large-period superstructure. We have directly observed an Einstein-like rattling mode at low energy, involving large anharmonic displacements of the sodium ions inside multi-vacancy clusters. These rattling modes suppress the thermal conductivity by a factor of six compared with vacancy-free NaCoO2. Our results will guide the design of the next generation of materials for applications in solid-state refrigerators and power recovery. [ABSTRACT FROM AUTHOR]

Background: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection of large lateral spreading tumors currently are technically limited by complications such as bleeding, perforation, and disturbed large procedural sites, leading to incomplete resection and secondary surgery. Further technical improvements are necessary. The authors previously demonstrated the effectiveness of a focused water jet for elevation of the lamina submucosa in animal studies. For the first time, the clinical application of selective tissue elevation by pressure (STEP) for the treatment of colorectal adenomas as a prospective single-arm human trial is presented. Methods: This trial evaluated 59 patients who had primary colorectal adenomas with diameters exceeding 12 mm classified as 0-IIa or 0-IIb according to Paris classification. A submucosal cushion was created with a flexible water jet applicator using the Helix HydroJet. The adenoma was subsequently resected with a mucosal resection snare. All results were recorded. The resected specimens were assessed histologically. Results: A total of 59 patients underwent resection of 70 lesions with a maximum diameter of 80 mm (mean, 27 mm). Submucosal elevation with the water jet dissector was possible in all cases and locations from the pectinate line to the ileocecal valve. Of the 70 lesions, 64 (91%) were resected completely in one session. Histologically, the resected specimens were found to be adenocarcinomas ( n = 2, 3%), adenomas with high-grade intraepithelial neoplasia ( n = 24, 34%), adenomas with low-grade intraepithelial neoplasia ( n = 38, 54%), and hyperplastic polyps ( n = 6, 9%). Hemostasis during the resection was necessary in 24 cases (34%). No perforation required surgical intervention. Conclusion: This first clinical trial to analyze STEP technique demonstrated that STEP used to elevate large mucosal lesions in any location is feasible and facilitates EMR for colorectal adenoma. [ABSTRACT FROM AUTHOR]

The heavy-fermion system CeCuAu which exhibits antiferromagnetic order for Au concentrations x>0.1, can be easily tuned to a quantum phase transition, either by chemical composition, i.e., Au concentration, or by an external magnetic field. We present extensive inelastic neutron scattering measurements in order to study the momentum and energy dependence of the critical spin fluctuations for concentration- and magnetic field-tuned CeCuAu. The quasi-2D fluctuations, observed for x=0.1 at the magnetic instability, are already present in pure CeCu and persist to x=0.2, i.e., well into the magnetically ordered regime. This is a strong hint that disorder does not play a major role in this system. The magnetic response for quantum critical CeCuAu exhibits critical slowing down and obeys scaling relations that depend on the tuning parameter. While the E/ T scaling of the dynamic susceptibility in concentration-tuned CeCuAu is an indication for local quantum criticality, the E/ T scaling in field-tuned CeCuAu points to a conventional spin-density-wave instability. [ABSTRACT FROM AUTHOR]

Argon plasma coagulation (APC) is a thermal coagulation technique that uses ionized argon for contact-free transmission of high-frequency electrical current to tissue. Prospective data on complications with the new APC-2 (VIO) system are lacking. A prospective trial was conducted with 152 patients treated for various gastrointestinal diseases using three modes of the APC-2. The study aimed to assess complications, focusing on the pain and neuromuscular stimulation (NMS) experienced during and after treatment. Patients reported pain and NMS using a scale ranging from 0 to 10 and were interviewed for symptoms such as tingling, paresthesia, muscle pain, and cramping or twitching. The endoscopists also graded NMS using a separate questionnaire. A total of 85 males and 67 females (median age, 66 years) were enrolled in the study. All APC therapies were completed successfully. Two peri-interventional perforations were recorded. Of the 152 patients, 26 (17%) reported pain sensation during or after APC. The median pain sensation reported by the patients on the standardized scale was 3.7. The findings showed NMS in 14 (9.2%) of the 152 patients. Significantly more NMS events were seen with pulsed APC than with forced or precise APC. Additional risk factors for NMS were gender (female) and type of sedation (combination midazolam and pethidine). No complications were noted among patients with intracardiac defibrillators or cardiac pacemakers. According to the findings, APC may be associated with minor complications such as pain sensation and NMS. These complications were rarely seen, but occurred more often with pulsed APC than with forced or precise APC. Physicians should be aware of these complications. [ABSTRACT FROM AUTHOR]

Background: Several new techniques have recently been described that allow the endoscopic mucosal resection even of broad-based flat lesions in the gastrointestinal tract. The technique recently described by us of using a water jet dissector (Helix HydroJet) for a selective deposition of liquid in the submucosal lamina has now been combined with different substances, and their effects have been compared.Material and Methods: Gastroscopies were carried out in 8 pigs under intubation anesthesia, and 2 submucosal cushions each were created in the stomach using one out of 4 test substances (gelatin, glucose 50, hydroxyethyl starch [HES] 10%, dextran 40), as well as one cushion of isotonic saline solution placed in each area via the Helix HydroJet). The height of the submucosal cushions was intermittently measured over a period of 40 or 20 min, respectively, by miniprobe endosonography. In 7 of the animals the stomach was subsequently subjected to mucosal resection. The specimens and the gastric wall were histologically assessed to evaluate the localization of the liquid cushion and the effect on adjacent layers of the gastric wall.Results: All test substances produced strictly selective liquid cushions in the submucosa. With HES 10% and dextran the maximum height of the cushions initially increased and then decreased during the further course to an average of 90% of the initial height within 40 min. Isotonic saline solution showed the most rapid decrease in height (72% after 20 min). The histological assessment confirmed the selective nature of the liquid deposit in the submucosa.Discussion: Plasma expanders produced cushions that initially increased in height but then remained constant for a longer period than cushions produced using glucose 50, gelatin, or isotonic saline solution. The combination of transmucosal jet application for elevation of the mucosa with plasma expanders is therefore an interesting approach to optimize endoscopic mucosal resections. [ABSTRACT FROM AUTHOR]

By means of susceptibility experiments on oxygen confined to the pores of a Gelsil substrate we investigated the bulk γ-β transition. At low fillings, the transformation is completely suppressed. At higher but still incomplete filling we observe a partial transformation from γ to β on cooling and a subsequent inverted transition on heating, i.e. the transformation of γ-phase material into the β-phase upon heating. At 100% filling this inversion disappears. We discuss our results on the basis of geometric considerations. [ABSTRACT FROM AUTHOR]

The magnetic phase diagram of the Fe2+ doped hexagonal ABX3 compound CsNi0.9Fe0.1Cl3 is investigated by heat capacity and magnetocaloric experiments. In spite of the high doping concentration, some phase boundaries appear surprisingly well-defined, while others are broadened significantly. The discussion of this behaviour clarifies the potentials and limitations of doping as a means to manipulate the effective anisotropy in quasi one-dimensional ABX3 compounds. [ABSTRACT FROM AUTHOR]

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The three-axis spectrometer IN20 has been upgraded to enhance significantly its performance in experiments using polarised neutrons in the (higher) thermal energy range. The neutron-source diameter was increased from 100 mm to 170 mm, and a new double-focusing Heusler monochromator with an active surface of 230 × 150 mm², illuminated through an input slit of adjustable width, has been installed. The maximum monochromatic polarised flux is close to 10[sup 8] cm[sup -2] s[sup -1] and, in combination with the horizontally focusing analyser of a similar design, the data-collection rate has increased by a factor of 30-50 as compared to the original IN20. [ABSTRACT FROM AUTHOR]