Novel measurement system for respiratory aerosols and droplets in indoor environments

The SARS-CoV-2 pandemic has created a great demand for a better understanding of the spread of viruses in indoor environments. A novel measurement system consisting of one portable aerosol-emitting mannequin (emitter) and a number of portable aerosol-absorbing mannequins (recipients) was developed that can measure the spread of aerosols and droplets that potentially contain infectious viruses. The emission of the virus from a human is simulated by using tracer particles solved in water. The recipients inhale the aerosols and droplets and quantify the level of solved tracer particles in their artificial lungs simultaneously over time. The mobile system can be arranged in a large variety of spreading scenarios in indoor environments and allows for quantification of the infection probability due to airborne virus spreading. This study shows the accuracy of the new measurement system and its ability to compare aerosol reduction measures such as regular ventilation or the use of a room air purifier.     

Soluble and conductive polypyrrole copolymers containing silicone tegomers

Soluble and processable conductive copolymers of silicone tegomers and pyrrole were developed. This was easily accomplished by the oxidative polymerization of pyrrole monomer by Ce(IV) salt in the presence of silicone tegomers with hydroxyl chain ends. The resulting copolymers were soluble in dimethylformamide. The products were characterized by Fourier transform infrared, ¹H‐NMR, and four‐point probe conductivity, and their surface properties were investigated with contact‐angle measurements. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2896–2901, 2003     

Oxygen plasma modification of poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) film surfaces for tissue engineering purposes

Plasma glow‐discharge application is known as a technique to coat or modify the surfaces of various materials. In this study, the influence of oxygen rf‐plasma treatment on surface and bulk properties of a biological polyester, poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate), were studied by determining water content and water contact angle, and by using X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The plasma‐treated films absorbed more water than the untreated film, and the absorbance increased with the total power applied. The water contact angles decreased and O/C atomic ratio increased on treatment, indicating that the material became more hydrophilic due to increases in the oxygen‐containing functional groups on the surface of the polymer. A direct relation could be observed when the O/C ratio was plotted against the total power applied (treatment duration × treatment power). SEM revealed a visual record of surface modification, the extent of which increased with increased total power. It was thus possible to alter the surface chemistry and relevant properties of the polymer film using oxygen plasma as a tool. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1285–1289, 2003     

Utilization of Electrospun Polystyrene Membranes as a Preliminary Step for Rapid Diagnosis

Recent advances in clinical practice drive deoxyribonucleic acid (DNA) as an important class of biomarker. Monitoring the change in their concentration suggests the initiation and/or progression of various disorders. However, low quantity of DNA biomarkers in body fluids requires a delicate isolation methodology that provides efficient separation and easy handling. This study describes a newer‐generation separation technology relying on electrospun fibers of sub‐micrometer diameter of a commodity polymer for DNA biomarkers in simulative serum. Fibrous polystyrene membranes are prepared by electrospinning and they are subjected to post‐modification with Au. The composite membranes may provide a convenient environment for the removal of bovine serum albumin (BSA) from BSA and DNA mixtures. The eluent can be used as an efficient tool for detection of DNA biomarkers associated with diagnosis of numerous life‐threatening diseases.

     

Allocation of energy inputs among the end-uses in the US petroleum and coal products industry

This paper models the allocation of energy inputs in the US petroleum and coal products industry by allocating combustible fuel and renewable energy inputs among generic end-uses, including intermediate conversions through onsite power and steam generation. This analysis, called an energy end-use model, showed that 72% of the fuel input in the US petroleum and coal products industry goes to onsite steam and power generation, whereas 28% goes directly to end-uses. Eight percent of the boiler output is used for power generation, 72% goes directly to end-uses, and 20% is waste heat. Among the end-uses, process heating is the biggest energy user with a total energy consumption of 2338 PJ, whereas machine drive is the biggest electricity consumer with a consumption of 168 PJ. This paper also provides estimates of the uncertainty of the data. The approach to create this model is applicable to all other industries for which data is available and the model is consistent with US Department of Energy data for 1998. When used in conjunction with similar models for other years, it can be used to identify the changes and trends in energy utilization even at the prime mover level of detail.     

Poly(ε‐caprolactone) composites containing gentamicin‐loaded β‐tricalcium phosphate/gelatin microspheres as bone tissue supports

In this work, novel antibacterial composites were prepared by using poly(ε‐caprolactone) (PCL) as the main matrix material, and gentamicin‐loaded microspheres composed of β‐tricalcium phosphate (β‐TCP) and gelatin. The purpose is to use this biodegradable material as a support for bone tissue. This composite system is expected to enhance bone regeneration by the presence of β‐TCP and prevent a possible infection that might occur around the defected bone region by the release of gentamicin. The effects of the ratio of the β‐TCP/gelatin microspheres on the morphological, mechanical, and degradation properties of composite films as well as in vitro antibiotic release and antibacterial activities against Escherichia coli and Staphylococcus aureus were investigated. The results showed that the composites of PCL and β‐TCP/gelatin microspheres had antibacterial activities for both bacteria. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Chemical Profile and Biological Activities of Two Edible Plants: Chemical Investigation and Quantitative Analysis Using Liquid Chromatography Tandem Mass Spectrometry and Gas Chromatography Mass Spectrometry

The objectives of this study were to define the phenolic and fatty acid profiles, anticholinesterase, antioxidant, antimicrobial activities, and total phenolic-flavonoid contents of Lycopsis orientalis and Tragopogon latifolius var. angustifolius which have been used as food source and food supplement in Anatolia and have never been examined before. Rosmarinic and quinic acids (21.11 and 11.46 mg g^–1 extract, respectively) were found to be the most abundant constituents in L. orientalis and T. latifolius var. angustifolius among the studied 27 compounds by liquid chromatography tandem mass spectrometry. In the fatty acid compositions of L. orientalis and T. latifolius var. angustifolius that were determined by gas chromatography mass spectrometry, oleic (29.1%) and palmitic (28.7%) acids were identified as the major components, respectively. The high antioxidant activity of the methanol extract of L. orientalis shows parallelism to its rosmarinic acid content. Besides, this extract showed medium anticholinesterase activity. The results of the present study proves that the L. orientalis might also be used as a food source due to its high phenolic acid content and strong antioxidant property.     

Green chemistry: microwave-assisted facile synthesis of 6-imino-1,3,4-thiadiazenes from reaction of thiocarbohydrazones with malononitrile dimer

The reactions of thiocarbohydrazones with malononitrile dimer under microwave irradiation are reported. These reactions give 6-imino-1,3,4-thiadiazines in good yields. The structures of products were elucidated by MS, IR and NMR spectra together with elemental analyses. The reaction mechanism was discussed.     

In vivo half life of nanoencapsulated L-asparaginase

In the present study, antileukemic enzyme L-asparaginase (ASNase) was encapsulated into poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanocapsules in order to decrease the immunogenicity and toxicity of the enzyme and to increase its in vivo half life in mice. Nanocapsules were prepared by water-in-oil-in-water approach and each phase was changed systematically. By changing the pH of the w₂ phase to the isolelectric point of L-ASNase, the encapsulation efficiency was increased from 23.7% to 28.0%. Also, modification of ASNase with PEG₂ increased the encapsulation efficiency from 23.7% to 27.9% and protected the enzyme against denaturation. Combination of the various optima enabled a substantial increase in the activity (0.074–0.429 U/mg nanocapsule). The enzyme activity in the blood due to unmodified PHBV nanocapsules dropped to 38% of its initial value 4 h after injection. When the same sample was tested for the enzyme content in the circulation by using the radio-labeled enzyme a much lower enzyme (30% of initial) could be detected after a shorter time (3 h). The PHBV nanocapsules with heparin conjugated on their surface had a longer presence in the circulation than unmodified PHBV nanocapsules. After 6 h, around 50% of the enzyme was still present in the blood. Radioactivity measurements using the same sample showed a sharp decrease in enzyme amount in the circulation in the early stages. However, radioactivity was still detectable at the eighth hour. No adverse effects and symptoms of anaphylaxis were observed upon injection of encapsulated ASNase-PHBV nanocapsules to mice i.v. through the tail vein.     

Transmutation-incineration potential of transuraniums discharged from PWR-UO2 spent fuel in modified PROMETHEUS fusion reactor

This study presents the potential of the burning and/or transmutation (B/T) of transuraniums (TRUs), discharged from the pressured water reactor PWR-UO₂ spent fuel, in the modified PROMETHEUS-H fusion reactor. Two different design shapes (Models A and B) were considered. The transmutation zone (TZ), which contains the mixture of TRU nuclides (10%), was located in the modified blankets. The volume fraction of Pu in the mixture is raised from 0 to 40% stepped by 10% to determine its effect on the B/T. The fuel spheres were cladded with SiC (5%) and cooled with high-pressured helium gas (85%) for nuclear heat transfer. The calculations were performed for an operation period (OP) of up to 10 years by 75% plant factor (η) under a neutron wall load (P) of 4.7 MW/m². The results bring out that: (1) the Model B transmutes the TRUs more rapidly than the Model A; (2) the effective half-lives decrease about 20 and 40% with the increase of Pu fraction in the cases of Models A and B, respectively; (3) the M values are quite high with respect to the M value of the original PROMETHEUS fusion reactor; (4) the blankets can produce substantial electricity in situ.