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The nonexponentiality and nonlinearity are two essential features of the structural relaxation in any glass-forming material, which seem to be inextricably bound together by the material time. It is shown that the temperature down-jump and up-jump experiments of the same magnitude Δ T = T 0 - T to the same temperature T provide a clue for their separation. The isothermal structural relaxation can be quantified using the stabilization period on the logarithmic time scale log( t m / t 0 ). It is described as the sum of the nonexponentiality term 1.181/ß and the nonlinearity term (σ/2.303)Δ T for the temperature down-jump, and as their difference for the temperature up-jump. The material parameter σ = -(∂lnτ/∂ T f ) i quantifies variation of the relaxation time with structural changes at the inflection point of the relaxation curve and is formulated for the most widely used phenomenological models. The asymmetry of approach to equilibrium after the temperature down-jump and up-jump was first described by Kovacs in 1963. A detailed analysis of this asymmetry is provided, and a simple method for the estimation of the parameters characterizing the nonexponentiality (ß) and nonlinearity (σ) is proposed. The applicability of this method is tested using previously reported isothermal experimental data as well as calculated data for aging of polymers and other glass-forming materials. This concept illuminates differences in structural relaxation kinetics in a simple and consistent way that can be useful in the design of novel materials and the evaluation of their physical aging treatment.

The seismic beacon is a new instrument that allows for the measurement of changes in a rock massif with high sensitivity. It is based on effects, which affect the propagation of harmonic seismic waves generated continuously with stable and precise frequency and amplitude. These seismic waves are registered by a system of seismic stations. The amplitude of the seismic signal is very small, and it is normally hidden in a seismic noise. Special techniques are applied to increase the signal-to-noise ratio. In 2020, the first prototype of the seismic beacon was constructed in a laboratory, and field tests were performed in 2022 and 2023. During the tests, the changes in spectral amplitude and phase of seismic waves were detected, which is interpreted as the changes in material properties. These measurements testified the basic functionality of the device. The seismic beacon has been developed primarily for the detection of critical stress before an earthquake, which is manifested by non-linear effects such as higher harmonics generation. In addition, it could be used, for example, in the detection of magma movements, groundwater level changes, changes in hydrocarbon saturation in rocks during the extraction of oil and natural gas, or the penetration of gases and liquids into the earth's crust.

The crystal growth kinetics and morphology in germanium disulfide bulk glass and glass surface is described. The structural relaxation taking place below the glass transition is slow and the corresponding volumetric change is negligible. Therefore, it does not affect substantially the crystal growth process. The crystal growth rate of low temperature β-GeS 2 and high temperature α-GeS 2 polymorphs in the bulk glass is comparable, being slightly decoupled from the shear viscosity below the glass transition. The crystal growth rate of β-GeS 2 in an amorphous thin film of the same composition is several orders of magnitude faster than that at the surface of bulk glass. This fast surface crystal growth is strongly decoupled from viscosity. Such behavior resembles the glass-to-crystal fast growth mode observed by several authors in some organic molecular glasses. Taking into account previously reported viscosity and heat capacity data, the crystal growth kinetics of both polymorphs can be quantitatively described by the 2D surface growth model for low and high supercooling. The nonisothermal differential scanning calorimetry experiments are analyzed, providing evidence of a complex nature of the overall crystallization process with apparent activation energy comparable to that obtained from isothermal microscopy measurement of crystal growth in the same temperature range.

Rotaphone-CY is a six-component short-period seismograph that is capable of the co-located recording of three translational (ground velocity) components along three orthogonal axes and three rotational (rotation rate) components around the three axes in one device. It is a mechanical sensor system utilizing records from elemental sensors (geophones) arranged in parallel pairs to derive differential motions in the pairs. The pairs are attached to a rigid frame that is anchored to the ground. The model design, the latest one among various Rotaphone designs based on the same principle and presented elsewhere, is briefly introduced. The upgrades of the new model are a 32-bit A/D converter, a more precise placing of the geophones to parallel pairs and a better housing, which protects the instrument from external electromagnetic noise. The instrument is still in a developmental stage. It was tested in a field experiment that took place at the Geophysical Observatory in Fürstenfeldbruck (Germany) in November 2019. Four Rotaphones-CY underwent the huddle-testing phase of the experiment as well as the field-deployment phase, in which the instruments were installed in a small-aperture seismic array of a triangular shape. The preliminary results from this active-source experiment are shown. Rotaphone-CY data are verified, in part, by various approaches: mutual comparison of records from four independent Rotaphone-CY instruments, waveform matching according to rotation-to-translation relations, and comparison to array-derived rotations when applicable. The preliminary results are very promising and they suggest the good functionality of the Rotaphone-CY design. It has been proved that the present Rotaphone-CY model is a reliable instrument for measuring short-period seismic rotations of the amplitudes as small as 10-7 rad/s.

Interest in measuring displacement gradients, such as rotation and strain, is growing in many areas of geophysical research. This results in an urgent demand for reliable and field-deployable instruments measuring these quantities. In order to further establish a high-quality standard for rotation and strain measurements in seismology, we organized a comparative sensor test experiment that took place in November 2019 at the Geophysical Observatory of the Ludwig-Maximilians University Munich in Fürstenfeldbruck, Germany. More than 24 different sensors, including three-component and single-component broadband rotational seismometers, six-component strong-motion sensors and Rotaphone systems, as well as the large ring laser gyroscopes ROMY and a Distributed Acoustic Sensing system, were involved in addition to 14 classical broadband seismometers and a 160 channel, 4.5 Hz geophone chain. The experiment consisted of two parts: during the first part, the sensors were co-located in a huddle test recording self-noise and signals from small, nearby explosions. In a second part, the sensors were distributed into the field in various array configurations recording seismic signals that were generated by small amounts of explosive and a Vibroseis truck. This paper presents details on the experimental setup and a first sensor performance comparison focusing on sensor self-noise, signal-to-noise ratios, and waveform similarities for the rotation rate sensors. Most of the sensors show a high level of coherency and waveform similarity within a narrow frequency range between 10 Hz and 20 Hz for recordings from a nearby explosion signal. Sensor as well as experiment design are critically accessed revealing the great need for reliable reference sensors.

A comparative active experiment that is aimed at collocated measurement of seismic rotation rates along three orthogonal axes by means of three different methods is described. The rotation rates in a short-period range of 6-20 Hz were obtained using three different methods: the 6C Rotaphone sensor system developed by the authors, the commercial R-1 rotational sensor by Eentec, and a small-aperture array of twelve standard velocigraphs in a rectangular arrangement. Those three methods are compared and discussed in detail. A medium-size quarry blast was used as a seismic source. At a distance of approximately 240 m, the rotation rates reached an amplitude of the order of magnitude of 10-4-10-5 rad/s. The array derived rotation rates displayed serious limitations, as clearly documented. The R-1 instruments have shown certain technical problems that partly limit their applicability. The measured rotation rates were compared to the relevant acceleration components according to rotation-to-translation relations. Out of all the three methods, the records best matching the acceleration components were made by Rotaphone. The experiment also revealed that rotation rates in the given short-period range noticeably changed over a distance as short as 2 m.

It is expected that viscous flow is affecting the kinetic processes in a supercooled liquid, such as the structural relaxation and the crystallization kinetics. These processes significantly influence the behavior of glass being prepared by quenching. In this paper, the activation energy of viscous flow is discussed with respect to the activation energy of crystal growth and the structural relaxation of glassy selenium. Differential scanning calorimetry (DSC), thermomechanical analysis (TMA) and hot-stage infrared microscopy were used. It is shown that the activation energy of structural relaxation corresponds to that of the viscous flow at the lowest value of the glass transition temperature obtained within the commonly achievable time scale. The temperature-dependent activation energy of crystal growth, data obtained by isothermal and non-isothermal DSC and TMA experiments, as well as direct microscopic measurements, follows nearly the same dependence as the activation energy of viscous flow, taking into account viscosity and crystal growth rate decoupling due to the departure from Stokes-Einstein behavior., Competing Interests: The authors declare no conflict of interest.

Crystal growth, viscosity, and melting were studied in Ge2Sb2Se5 bulk samples. The crystals formed a compact layer on the surface of the sample and then continued to grow from the surface to the central part of the sample. The formed crystalline layer grew linearly with time, which suggests that the crystal growth is controlled by liquid-crystal interface kinetics. Combining the growth data with the measured viscosities and melting data, crystal growth could be described on the basis of standard crystal growth models. The screw dislocation growth model seems to be operative in describing the temperature dependence of the crystal growth rate in the studied material in a wide temperature range. A detailed discussion on the relation between the kinetic coefficient of crystal growth and viscosity (ukin ∝ η(-ξ)) is presented. The activation energy of crystal growth was found to be higher than the activation energy of crystallization obtained from differential scanning calorimetry, which covers the whole nucleation-growth process. This difference is considered and explained under the experimental conditions.

The project involves determination of the activation energies and physical models for thermolysis of BCHMX and its PBXs. The initial decomposition pathways were also proposed on the basis of molecular dynamic simulation. The goal is to find the mutual relationships among the physical models, decomposition pathways, and the impact sensitivities for BCHMX and its PBXs. It has been shown that the physical model of the first step of BCHMX thermolysis is close to first order and the second step is governed by a first order autocatalytic model, which turns to "2D or 3D Nucleation and Growth" models under the effect of polymeric binders probably due to their hindrances on topochemical reaction of BCHMX. Simulation results show that the scission of N-NO2 is the initial step for BCHMX pyrolysis, followed by HONO and HNO eliminations, where the latter is due to nitro-nitrite rearrangement. Under the effect of hydrocarbon polymers, the HONO/HON elimination and collapse of ring structure of BCHMX occur earlier without changing the time for N-NO2 scission, which might be the reason why those polymers have little effect on the thermal stability of BCHMX, while they could make it decompose almost in a single complex step., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Heat capacity measurements were performed for Se, Se90Te10, Se80Te20, and Se70Te30 materials in the 230-630 K temperature range. Both glassy and crystalline Cp dependences were found to be identical within the experimental error. The compositional dependence of the N-type undercooled liquid Cp evolution was explained on the basis of free-volume theory; vibrational and chemical contributions to heat capacity were found to be roughly similar for all Se-Te compositions. The thermal behavior in the Se-Te chalcogenide system was thoroughly studied: glass transition, cold crystallization, and melting were investigated in dependence on composition and various experimental conditions (heating rate, particle size, and pre-nucleation period). The kinetics of the structural relaxation and crystallization processes are described in terms of the Tool-Narayanaswamy-Moynihan and Johnson-Mehl-Avrami models. The complexity of these processes is thoroughly discussed with regard to the compositionally determined changes of molecular structures. The discussion is conducted in terms of the mutual interplay between the thermodynamics and kinetics in this system.

In this paper, the decomposition reaction models and thermal hazard properties of 1,3,5-trinitro-1,3,5-triazinane (RDX) and its PBXs bonded by Formex P1, Semtex 1A, C4, Viton A and Fluorel polymer matrices have been investigated based on isoconversional and combined kinetic analysis methods. The established kinetic triplets are used to predict the constant decomposition rate temperature profiles, the critical radius for thermal explosion and isothermal behavior at a temperature of 82°C. It has been found that the effect of the polymer matrices on the decomposition mechanism of RDX is significant resulting in very different reaction models. The Formex P1, Semtex and C4 could make decomposition process of RDX follow a phase boundary controlled reaction mechanism, whereas the Viton A and Fluorel make its reaction model shifts to a two dimensional Avrami-Erofeev nucleation and growth model. According to isothermal simulations, the threshold cook-off time until loss of functionality at 82°C for RDX-C4 and RDX-FM is less than 500 days, while it is more than 700 days for the others. Unlike simulated isothermal curves, when considering the charge properties and heat of decomposition, RDX-FM and RDX-C4 are better than RDX-SE in storage safety at arbitrary surrounding temperature., (Copyright © 2014 Elsevier B.V. All rights reserved.)

GC with nitrogen phosphorus detection and HPLC with UV detection were used to determine midazolam (MDZ) levels in rabbit plasma following ocular and nasal administration. For GC with nitrogen phosphorus detection, the analyte was extracted from the plasma using a three-step liquid-liquid extraction including extraction with an isopropanol/butyl chloride mixture in an alkaline solution, followed by extractions with 1 M HCl, and finally with an alkaline solution of butyl chloride. The recovery of MDZ was dependent on the sample alkalization time prior to the final extraction. The procedure increased the recovery of MDZ up to 99.6%. Improved sample preparation led to a significant increase in the sensitivity of the determination by GC with nitrogen phosphorus detection. The achieved detection limit was 0.34 ng/mL, which is ten times lower than that obtained using HPLC with UV detection. The small plasma volume was another advantage of the GC with nitrogen phosphorus detection method (200 μL per assay). Both administration routes of the anesthetic (nasal and ocular) resulted in comparable plasma MDZ levels. Kinetic simulation of the MDZ plasma was performed for both administration routes., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Irreversible electroporation (IRE) is a new method of local therapy of malign tumours based on bioelectric effect of electrical current. Short electric pulses with high voltage create nano size-pores in tumour cell membranes resulting in apoptosis of the exposed cells. The purpose of our study was to verify the IRE technique performed percutaneously under CT navigation and to assess effects of application of this method in early stages of primary and secondary hepatic, pancreatic, renal and pulmonary tumours., Methods and Results: From November 2011 to October 2012 IRE was performed with NanoKnife (by AngioDynamics) in the population of 15 patients - 6 males and 9 females. IRE was performed under total anaesthesia with 2-5 needle electrodes introduced under CT navigation in the tumour base. The results of the treatment were assessed on the basis of modified RECIST criteria applied in 1-, 3- and 6-month intervals. A control CT or MRI examination 6 months post IRE was undertaken by 10 patients. One patient died one month post IRE of pulmonary embolism, two refused to visit for the control examination and another two are still to undergo the examination after 6 months. Out of the 10 examined patients success of IRE was demonstrated in 7 cases (70.0%) and IRE failure in 3 patients (30.0%)., Conclusion: IRE is a new, mini-invasive therapeutic method applicable to local treatment of malignant tumours in cases where surgical approach is technically unfeasible or excessively risky. On the basis of first experience in a small cohort of patients IRE performed under CT navigation appears to be an effective and safe ablation method with a large therapeutic potential. Its results will however need to be assessed within a longer time horizon and in a larger cohort of population.

We have developed and tested (calibration, linearity, and cross-axis errors) a new six-degree-of-freedom mechanical seismic sensor for collocated measurements of three translational and three rotational ground motion velocity components. The device consists of standard geophones arranged in parallel pairs to detect spatial gradients. The instrument operates in a high-frequency range (above the natural frequency of the geophones, 4.5 Hz). Its theoretical sensitivity limit in this range is 10(-9) m/s in ground velocity and 10(-9) rad/s in rotation rate. Small size and weight, and easy installation and maintenance make the instrument useful for local-earthquake recording and seismic prospecting.

Objective: To develop a safe and effective immobilization protocol in rhesus monkeys, which is not based on dissociative anaesthetic agent., Study Design: Prospective, randomised, experimental trial., Animals: Twenty rhesus monkeys, weighing 2.6-8.0 kg, 1-3 years of age, of both sexes., Methods: The monkeys received 50 μg kg(-1) medetomidine, 0.25 mg kg(-1) midazolam and 5 μg kg(-1) fentanyl with 150 IU hyaluronidase intramuscularly (IM). The animals were closely observed for behavioural changes and reaction to sound stimulus. Pulse rate and oxygen saturation of haemoglobin (SpO(2) ) were monitored every 5 minutes, for 20 minutes. After this period, 250 μg kg(-1) atipamezole or a placebo was administered IM and behavioural changes were closely observed., Results: Full immobilization was observed after mean 269 ± SD 116 seconds. Ten minutes after injection mean arterial oxygen saturation of haemoglobin was 94 ± 4%, but did not fall significantly further. The median pulse rate was 116 beats minute(-1) 5 minutes after the administration of the drug. This level further decreased to a median level of 108 beats minute(-1) 20 minutes after the drug's administration. The median time to recover from immobilization was significantly shorter after atipamezole administration when compared to placebo (2.7 versus 55 minutes). All animals awoke smoothly and no side effects such as vomiting or agitation were observed., Conclusions: Short term and reversible pharmacological immobilization was achieved using combination of midazolam, medetomidine, and fentanyl., Clinical Relevance: The present study demonstrates that 20-minute pharmacological immobilization with a combination of midazolam, medetomidine, and fentanyl is feasible in rhesus monkeys with minimal effect on heart rate., (© 2011 The Authors. Veterinary Anaesthesia and Analgesia. © 2011 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.)

Objectives: To assess the outcome of self-expandable, biodegradable stent insertion for anastomotic strictures following treatment for rectosigmoid carcinoma., Methods: Three male patients (median age 66) developed benign strictures after radiotherapy and resection of a recto-sigmoid carcinoma. These were resistant to balloon dilatation and prevented stoma reversal. Biodegradable stent insertion was performed as an experimental treatment on a named-patient basis with approval of the institutional review board. Patients had monthly follow-up with endoscopy and contrast medium enemas to monitor performance and degradation of the stents., Results: All stents were placed successfully without complications after pre-dilatation to 20 mm under fluoroscopic guidance. Stent degradation occurred in all patients 4-5 months following implantation, and long-term anastomotic patency was demonstrated in all. This allowed reversal of the colostomy and physiological defecation in two patients. Reversal was not undertaken in one due to subsequent development of liver metastases. No stent migration or occlusion occurred., Conclusions: Biodegradable stents can maintain an adequate lumen across anastomotic strictures resistant to balloon dilatation. They seem to allow stricture re-modelling resulting in maintained dilatation after degradation. This potentially allows reversal of a colostomy, which might otherwise be prevented by stricture recurrence.