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Pectineal ligament hysteropexy is a safe technique that gives durable support to the prolapsed uterus with low recurrence rates.

Surface modification of carbon black by plasma polymerization was aimed to reduce its surface energy in order to compatibilize the filler with various elastomers. A fullerenic carbon black was used for the modification process. Thermogravimetric analysis, wetting behavior with liquids of known surface tension, TEM and TOF‐SIMS were used to characterize the carbon black before and after modification. The state of plasma‐coated carbon black in rubber was studied by means of conductivity measurements. The behavior of the modified filler in rubber was studied using the Payne effect and stress/strain properties. The study shows that plasma‐coated carbon black results in a better dispersion in different rubber systems than the uncoated version.

Surface modification of sulfur by vacuum plasma polymerization with acetylene was applied in order to modify its surface properties without losing reactivity for vulcanization. A nmthin layer of crosslinked polyacetylene was deposited on the surface of the sulfur powder. Its surface energy was decreased as monitored by wetting in liquids of various polarities. A delay in the onset of weight loss by sublimation in thermal gravimetric analysis was shown by the plasmamodified sulfur. Scanning electron microscopy showed a coreshell structure of the coated sulfur. In 50:50 blends of styrenebutadiene rubber and ethylenepropylenediene rubber, the encapsulated sulfur samples resulted in pronounced improvements in the mechanical properties relative to the use of unmodified sulfur.

APPS has been used to modify EPDM in order to solve the cure incompatibility and heterogeneous filler distribution of NRBREPDM blends for tire sidewall applications. The physical properties of the NRBRAPPSEPDM blends are compared with an NRBREPDM blend and a conventional NRBR tire sidewall. It is demonstrated that the application of APPSEPDM leads to a significant improvement of the tensile properties, tear strength, and fatigue properties. The properties of the NRBRAPPSEPDM blends are equivalent or even superior to those of conventional NRBR tire sidewall compounds. The dynamic viscoelastic properties of the NRBRAPPSEPDM blends are not quite comparable with the conventional NRBR sidewall blend, but still greatly improved, compared to using virgin EPDM.

Using previously obtained data on the solubilities of curatives in SBR, EPDM and in NBR, different mixing procedures were performed on 5050 SBREPDM and NBREPDM blends. In contrast to a previous phasemixing study, the curatives were added to separate phases before final blending, in an attempt to control the curative distributions in the blends for optimal mechanical properties. Fillers were not applied in the system to exclude their influence on the dispersion of the curatives. The properties of such blends compounded by selective phase mixing are superior to those of blends compounded with normal mixing procedures.

The current study provides indications for improving the properties of dissimilar rubber blends. As solubility is a key factor for the distribution and a driving force for the migration of curatives in dissimilar rubber blends, it is of importance to have precise data of their solubilities. The solubilities of insoluble sulfur and the accelerators CBS, MBT and DCBS are measured at RT and at 60 °C, in lightly crosslinked SBR, NBR and EPDM. The experimental results correlate well with calculated solubility parameters, as determined using the method of Hoftijzer and van Krevelen.

Because of environmental concerns, the zinc content in rubber compounds has come under scrutiny. The research described in this article encompasses zinc‐oxide, various zinc‐complexes and alternative metal oxides as activators for sulphur vulcanisation. Regarding zinc complexes, it can be concluded that zinc‐ m‐glycerolate is a good substitute for ZnO as activator for sulphur vulcanisation in s‐SBR rubber, without detrimental effects on the cure characteristics. Of particular interest is also the positive effect of CaO and MgO in s‐SBR, while BaO, Cu(II)O and BeO hardly show any activation. The present article also reports on the application of a novel activator for sulphur vulcanisation: ZnClay. Results with s‐SBR rubber demonstrate, that this ZnClay can substitute conventional ZnO, retaining the curing and physical properties of the rubber products, while significantly reducing the environmental impact. A reduction of the zinc concentration with a factor 10 to 20 can be realised. Model Compound Vulcanisation studies are used to gain insight into the mechanism of this activator.

The HADES spectrometer and a time-of-flight detector based on long-sized (50–250 cm) scintillation counters are described. The detector is designed for identification of electrons, pions, and protons with momenta of 0.1–1.5 GeV/cat a flight distance of 220–250 cm. The operating conditions are analyzed, and the requirements to the detector and counter design are formulated. The design of the counters and their arrangement in the spectrometer are considered. The results of experimental studies of such characteristics of long counters as the light attenuation length in a scintillator and temporal and spatial resolutions, dependeing on the location of the point of the particle’s hit on the counter, are presented. Analysis of the data has shown that the main factor determining the spatial resolution of long counters is the quality of the polishing of the side faces of the scintillators, which determines the effective (averaged over the scintillator side surfaces) coefficient of total internal reflectionR. It is shown that, forR>-0.99, it is quite possible to achieve temporal and spatial resolutions of 100 ns and 2–3 cm, respectively, for scintillators with a length of up to 250 cm and a cross section of 1–20 cm2. Foreign and Russian photomultipliers were used in the counters.

A drug–excipient compatibility screening model was developed by which potential stability problems due to interactions of drug substances with excipients in solid dosage forms can be predicted. The model involved storing drug–excipient blends with 20% added water in closed glass vials at 50 °C and analyzing them after 1 and 3 weeks for chemical and physical stability. The total weight of drug–excipient blend in a vial was usually kept at about 200 mg. The amount of drug substance in a blend was determined on the basis of the expected drug‐to‐excipient ratio in the final formulation. Potential roles of several key factors, such as the chemical nature of the excipient, drug‐to‐excipient ratio, moisture, microenvironmental pH of the drug–excipient mixture, temperature, and light, on dosage form stability could be identified by using the model. Certain physical changes, such as polymorphic conversion or change from crystalline to amorphous form, that could occur in drug–excipient mixtures were also studied. Selection of dosage form composition by using this model at the outset of a drug development program would lead to reduction of “surprise” problems during long‐term stability testing of drug products.

A drug–excipient compatibility screening model was developed by which potential stability problems due to interactions of drug substances with excipients in solid dosage forms can be predicted. The model involved storing drug–excipient blends with 20% added water in closed glass vials at 50 °C and analyzing them after 1 and 3 weeks for chemical and physical stability. The total weight of drug–excipient blend in a vial was usually kept at about 200 mg. The amount of drug substance in a blend was determined on the basis of the expected drug-to-excipient ratio in the final formulation. Potential roles of several key factors, such as the chemical nature of the excipient, drug-to-excipient ratio, moisture, microenvironmental pH of the drug–excipient mixture, temperature, and light, on dosage form stability could be identified by using the model. Certain physical changes, such as polymorphic conversion or change from crystalline to amorphous form, that could occur in drug–excipient mixtures were also studied. Selection of dosage form composition by using this model at the outset of a drug development program would lead to reduction of “surprise” problems during long-term stability testing of drug products.

Examines the use of short fibers from aromatic polyamide as a tread material for rubber tires. Concerns raised over the retreadability and low rolling resistance of tires; Potential role of fibers in reducing tire wear; Stages of mixing rubber compounds.

Investigates the use of triethoxysilylpropyl tetrasulfide (TESPT) in silica reinforced rubber compounds for passenger cars. Drawbacks in the applications of silica technology; Attempts made to reduce and optimize the loading of TESPT in rubber compounds; Exploration of the use of aramid short fibers in balancing processing and performance benefits of TESPT.

Abstract: We introduce a novel real-time algorithm for automatic acoustic-based vehicle detection. Commonly, surveillance systems for this task use a microphone that is placed in a target area. The recorded sounds are processed in order to detect vehicles as they pass by. The proposed algorithm uses the wavelet-packet transform in order to extract spatio-temporal characteristic features from the recordings. These features constitute a unique acoustic signature for each of the recordings. A more compact signature is derived by the application of the Diffusion Maps (DM) dimensionality reduction algorithm. A new recording is classified according to its compact acoustic signature in the DM reduced-dimension space. The signature is efficiently obtained via the Geometric Harmonics (GH) algorithm. The introduced algorithm is generic and can be applied to various signal types for solving different detection and classification problems. [Copyright &y& Elsevier]

Multiple myeloma is a bone marrow-based plasma cell tumour that develops from asymptomatic pre-cursor conditions smouldering myeloma and monoclonal gammopathy of uncertain significance and all are characterised by the presence of a monoclonal protein in the blood. Diagnosis and distinction between these conditions is based on blood tests, the bone marrow biopsy and cross sectional imaging. There are various risk stratification models that group patients with smouldering myeloma into risk groups based on risk of progression to symptomatic disease. Management is mainly observational for patients with smouldering myeloma although clinical trials for high-risk disease may be available. Restaging is required if evidence for progression., (© 2024 British Society for Haematology and John Wiley & Sons Ltd.)