From binary to multinary copper based nitrides - unlocking the potential of new applications

This review summarizes the current knowledge on the chemistry of binary copper(I) nitride, Cu3N and its multinary derivatives containing either main group or transition metal elements. For many years, research in this area was focused on the development of copper nitride prepared in the form of thin films. Successful deposition of these materials has been achieved mainly by employing physical methods, which have provided materials suitable for potential application in optical data storage. However, for the last decade, attention has also been devoted to expanding the available options by which Cu3N can be synthesized and deposited. Consequently, the focus has switched to the development of chemical synthetic methods towards the fabrication of this semiconductor and to broadening the range of related compounds that might be discovered. Simultaneously, the formulation of novel techniques and the successful preparation of new nanostructured functional materials has resulted in the rapid evolution of new and relevant applications; e.g. catalytic and electrochemical. The overview presented here concentrates on the chemical methods that have been devised to synthesise both bulk samples and thin films of Cu3N. Our article also shows how these approaches have been developed to achieve significant progress in the creation of multinary copper based nitrides and in identifying their potential applications. It provides a concise history of previous copper nitride research and sets the context for the most current advances. These will no doubt provide the springboard for future research areas that will impact both transition metal nitride chemistry and materials science more generally

Device for on-line measurement of low value pressures in medicine and physiology

Codzienna praktyka kliniczna, badania kliniczne i doświadczalne wymagają aparatury umożliwiającej dokonywanie pomiarów ciśnień równolegle w wielu kompartmentach tkankowych i w układzie naczyniowym z dużą dokładnością w czasie rzeczywistym. Dla tych zastosowań stworzono prototyp aparatury umożliwiającej wielopunktowe (do 8 sond) pomiary ciśnień z rozdzielczością do 0,01 mmHg w zakresie -150 do +300 mmHg, z częstotliwością 100 Hz. System składa się z zestawu sond ciśnie-nia, 24 bitowego przetwornika A/C, niskomocowego procesora obróbki wstępnej digitalizującego mierzone parametry ciśnień, oraz nadajnika radiowego (2.4 GHz) przekazującego bezprzewodowo mierzone wartości ciśnień do kontrolera umieszczonego w pewnej odległości od miejsca pomiaru. Skonstruowane urządzenie dzięki znacznej miniaturyzacji eliminującej wpływ elementów urządzenia na mierzone ciśnienia oraz znacznie zmniejszające uciążliwość długotrwałych pomiarów dla chorego, wysoka precyzja pomiarów wykonywanych w czasie rzeczywistym z wysoką częstotliwością oraz autonomiczne źródło zasilania sond pomiarowych umożliwiające długotrwałe (do 72 godzin) pomiary rokują jego szerokie zastosowania w praktyce medycznej, w badaniach klinicznych i doświadczalnych.For medical purpose, clinical diagnosis and physiological experiments an equipment enabling on-line monitoring of pressure in tissue compartments as well as blood and lymphatic vessels with high-precision is required. Thus, a prototype of the equipment for on-line measurements of pressures ranging from -150 to +300 mmHg with high resolution (0,01 mmHg) in up to 8-channels simultaneously with frequency up to 100 Hz was manufactured. It consists of a set of high precision pressure microprobes enabling parallel measurements of pressure in several tissues and intravascular compartments (in the presented prototype up to 8 probes), a 24-bit ADC low-power micro-controller digitalizing pressure values and a 2.4 GHz radio transceiver for wireless data transfer from pressure probes to the extracorporeal controller. Miniaturization, autonomic power supply and lack of cable connectors allowed reducing the influence of equipment components on the measured pressure and improved patient's comfort during long-lasting measurements. The constructed equipment enables high precision, long-lasting (up to 72 hours), on-line pressure measurements for medical and laboratory applications

Short ingestion tests as alternative proposal for conventional range finding assays with Thamnocephalus platyurus and Brachionus calyciflorus

The goal of this study was to evaluate whether short 1 h sublethal assays may predict the results of 24 h lethality assays with rotifers Brachionus calyciflorus and anostracan crustaceans Thamnocephalus platyurus . The test bionts were hatched from cysts. Inhibition of ingestion was observed after 15 min of incubation of rotifers and crustaceans with the suspension of carmine and latex beads, respectively. Nine compounds with different modes of action were used as toxicants zinc ions, sodium dodecyl sulphate, p-nitrophenol, 3, 5-dichlorophenol and pharmaceuticals propranolol, fluoxetine, abamectin, doramectin and ivermectin. The toxicity values observed in the ingestion tests were very close to the mortality values over a wide range of toxicity from a low toxic surfactant to very toxic avermectins. The ratio between the 1 h EC50’s in the ingestion test and the 24 h LC50’s in the lethality test was below 2 in all cases for rotifers, and 7 in 9 cases for crustaceans. The toxicity of zinc and 3,5-dichlorophenol in the Thamnotoxkit F™ was 15-fold higher and 10 fold lower than in the ingestion test, respectively. The 24 h LC50 values are within the range of 25-400 % of the 1 h EC50 values for almost all toxicants tested with the exception of p-nitrophenol for B. calyciflorus and zinc and 3, 5-dichlorophenol for T. platyurus. Short, 1 h ingestion assays Rotoxrapid and Rapidtoxkit are good predictors of the mortality over the next 24 h and can be used as a range finding tests for representatives of pharmaceuticals and surfactants

A Review on Biomaterials for Orthopaedic Surgery and Traumatology: From Past to Present

The principal features essential for the success of an orthopaedic implant are its shape, dimensional accuracy, and adequate mechanical properties. Unlike other manufactured products, chemical stability and toxicity are of increased importance due to the need for biocompatibility over an implants life which could span several years. Thus, the combination of mechanical and biological properties determines the clinical usefulness of biomaterials in orthopaedic and musculoskeletal trauma surgery. Materials commonly used for these applications include stainless steel, cobalt-chromium and titanium alloys, ceramics, polyethylene, and poly(methyl methacrylate) (PMMA) bone cement. This study reviews the properties of commonly used materials and the advantages and disadvantages of each, with special emphasis on the sensitivity, toxicity, irritancy, and possible mutagenic and teratogenic capabilities. In addition, the production and final finishing processes of implants are discussed. Finally, potential directions for future implant development are discussed, with an emphasis on developing advanced personalised implants, according to a patient’s stature and physical requirements

Molecular Dynamics and Physical Stability of Ibuprofen in Binary Mixtures with an Acetylated Derivative of Maltose

In this paper, we explore the strategy increasingly used toimprove the bioavailability of poorly water-soluble crystalline drugs byformulating their amorphous solid dispersions. We focus on the potentialapplication of a low molecular weight excipient octaacetyl-maltose (acMAL) toprepare physically stable amorphous solid dispersions with ibuprofen (IBU)aimed at enhancing water solubility of the drug compared to that of itscrystalline counterpart. We thoroughly investigate global and local moleculardynamics, thermal properties, and physical stability of the IBU+acMAL binarysystems by using broadband dielectric spectroscopy and differential scanningcalorimetry as well as test their water solubility and dissolution rate. Theobtained results are extensively discussed by analyzing several factorsconsidered to affect the physical stability of amorphous systems, includingthose related to the global mobility, such as plasticization/antiplasticization effects, the activation energy, fragility parameter, and thenumber of dynamically correlated molecules as well as specific intermolecular interactions like hydrogen bonds, supporting the latterby density functional theory calculations. The observations made for the IBU+acMAL binary systems and drawn recommendationsgive a better insight into our understanding of molecular mechanisms governing the physical stability of amorphous solid dispersions