Porous poly(urethane urea) microparticles for immobilization of maltogenic α amylase from Bacillus stearothermophilus

Maltogenic α amylase from Bacillus stearothermophilus (BsMa) was immobilized by covalent attachment and physical adsorption onto porous poly(urethane urea) (PUU) microparticles obtained from poly(vinyl alcohol) (PVA) and 4,4’-methylenebis(cyclohexyl diisocyanate) (H12DI) by onepot synthesis. The influence of PUU synthesis parameters such as PVA and H12DI molar ratio, synthesis time and temperature on porosity, surface area, structure of microparticles and catalytic activity and stability of immobilized BsMa was investigated. The highest efficiency of the immobilization of BsMa onto the PUU carrier was 97% and the highest residual stability of the immobilized enzyme reached 95% after 28 days of storage at 4°C. The optimal activity temperature of immobilized BsMa was at 80°C and it was higher than that of native enzyme. Effects of ionic strength and repetitive batch processing cycles on the activity of immobilized BsMa were also studied. Immobilization of BsMa onto PUU carriers has a great potential for biotechnology and food industries.

VERIFICATION OF TACTICAL AND TECHNICAL DATA OF THE BREATHING APPARATUS

The function of the breathing apparatus is to protect the health of firefighters in a harmful and non-respirable environment. Closed-circuit breathing apparatus provides members of the Fire and Rescue Service with respiratory protection in the elimination of adverse events in tunnels and underground spaces. The MSA 4h Air Elite is a four-hour self-contained breathing apparatus that operates on the principle of generating oxygen by an exothermic reaction of potassium hyperoxide. Each breathing apparatus has its tactical technical parameters. We verified the tactical and technical data of the MSA AIRE ELITE by the experiment they participated in the firefighter. Each firefighter was equally coupled. An MSA Air Elite was used during the experiment. Tactical-technical data reported by the manufacturer varies in some points with the practical results that we have managed to obtain. The manufacturer's largest deviations in tactical and technical data and practical results are mainly in the length of work activity, temperature in use in intervention, and air consumption. According to our experiment, the MSA 4h Air Elite breathing apparatus does not last in the working activity 240 minutes as it discloses a manufacturer, but on the other hand, this time-inconsistency may be caused by the intensity of training and demanding of the training track.

Physicochemical Properties of MoVTeNb Mixed Oxide Catalysts Synthesized using Different Vanadium Sources

The use of different vanadium sources in the synthesis of multi-metal MoVTeNb oxide catalysts has been investigated for their effect on the physicochemical properties of catalysts. Metal oxides were synthesized by slurry method assisted with a microwave irradiation. Vanadium pentoxide (V2O5), vanadyl sulphate (VOSO4) and ammonium metavanadate (NH4VO3) were used as the vanadium sources, respectively. X-ray diffraction (XRD) pattern showed the existence of orthorhombic (M1) phases in all catalysts. The catalyst prepared using V2O5 produced the highest formation of the phase. This was further supported by Inductive Couple Plasma-Atomic Emission Spectroscopy (ICP-AES), which showed that the V2O5 catalyst has the highest V: Mo ratio, mainly responsible for the high catalytic activity. Temperature Programmed Reduction in Hydrogen (H2-TPR) showed better reducibility for the catalyst when compared to the others. Temperature Programmed Reaction (TPRn) confirmed that the oxidants active for propane conversion into acrylic acid were originated from the lattice of the catalyst.

Biomass of unconventional plants from Brazilian semiarid as substrate for hydrolytic enzymes production by Aspergillus niger under solid and submerged fermentation

Aspergillus niger KIJH was grown in solid and submerged fermentation using leaves and roots (with and without bark) of plants typically from Brazilian semiarid as substrate to produce a multienzymatic extract, which was characterised for its potential biotechnological applications. Solid-state fermentation (SSF) was applied to select the most promising plants biomass as induction substrates for the production of hydrolytic enzymes by fungus. The best biomasses were used as substrate in submerged fermentation (SmF) assays at two scales. Samples of up scale fermented culture were partially purified by ultrafiltration and activity and pH and temperature stability of CMCase and xylanase were evaluated. A. niger KIJH produced hydrolytic enzymes under SSF containing unconventional plants biomass from Brazilian semiarid. In SmF conditions, maximum CMCase (0.264 U mL-1) and xylanase (1.163 U mL-1) activities were induced by Jacaratia corumbensis. Scaling up the SmF to 500 mL of medium was able to maintain constant the production of CMCase (0.346 U mL-1) and xylanase (1.273 U mL-1) on the fermented culture. Ultrafiltered and concentrated extract presented CMCase activities practically constant in all temperature ranges (30-80°C) and pH (3.0-9.0), while xylanase optimum activity temperature was 50°C and pH in the range of 3.0 to 5.0. CMCase activity remained stable for 24 hours at 50°C and xylanase was reduced in 53% after two hours incubation at the same temperature. CMCase and xylanase obtained by A. niger KIJH cultivated in submerged culture containing J. corumbensis as carbon source may have application in biotechnology processes that require enzymes that remain active under routine extreme conditions.

Gut markers of bodily self-consciousness

Bodily self-consciousness, the state of mind that allows humans to be aware of their own body, forms the backdrop for almost every human experience, yet its underpinnings remain elusive. Here we use an ingestible, minimally invasive capsule and surface electrogastrography to probe if gut physiology correlates with bodily self-consciousness during a virtual bodily illusion. We discover that specific patterns of stomach and large intestine activity (temperature, pressure, pH, and gastric peak frequency) covary with specific facets of bodily self-consciousness (feelings of body ownership, agency, location, and disembodiment). Furthermore, we show that the link between gastro-intestinal parameters and bodily self-consciousness depends also on individual levels of interoception. These results reveal a deep visceral pathway to the self-conscious perception of ourselves as embodied beings.

Effects of Climate Change on Invasive Species

Mean surface temperatures have increased globally by ~0.7 °C per century since 1900 and 0.16 °C per decade since 1970 (Levinson and Fettig 2014). Most of this warming is believed to result from increases in atmospheric concentrations of greenhouse gases produced by human activity. Temperature increases have been greater in winter than in summer, and there is a tendency for these increases to be manifested mainly by changes in minimum (nighttime low) temperatures (Kukla and Karl 1993). Changes in precipitation patterns have also been observed, but are more variable than those of temperature. Even under conservative emission scenarios, future climatic changes are likely to include further increases in temperature with significant drying (drought) in some regions and increases in the frequency and severity of extreme weather events (IPCC 2007). For example, multimodel means of annual temperature from climate projections predict an increase of 3–9 °C in the United States over the next century combined with reductions in summer precipitation in certain areas (Walsh et al. 2014). These changes will affect invasive species in several ways. Furthermore, climate change may challenge the way we perceive and consider nonnative invasive species, as impacts to some will change and others will remain unaffected; other nonnative species are likely to become invasive; and native species are likely to shift their geographic ranges into novel habitats.

Physicochemical simulation of the conditions for the mafic granulite formation (Bunger Hills, East Antarctica)

The article presents the results of mineral thermobarometry and physico-chemical simulation of the formation of garnet-enstatite gneiss from the Mesoproterozoic metamorphic suite of the Bunger Hills, East Antarctica. As a result, the water activity, temperature and pressure of rock formation were estimated. It is shown that the peak temperature of metamorphism could reach 900 °С or more. Such temperature conditions indicate the prerequisites for the occurrence of UHT-metamorphism during the formation of the East Antarctic Shield.

Partial Purification of a Catalase from an Improved Nigerian Sorghum Grain Variety

Catalases are key components of cellular detoxification pathways that prevent the formation of highly reactive hydroxyl radicals through catalyzing the decomposition of hydrogen peroxide into water and molecular oxygen. Their presence in brewery grains prevent the inactivation of important brewery enzymes and also stop lipid peroxidation. To determine their occurrence and establish some of its properties in sorghum, which has become as an important brewery grain similar to barley, crude catalase was obtained from a sorghum grain variety. Preliminary purification of catalase from the sorghum grain variety used, NRL-3, showed that the enzyme was purified 3.2-fold from the crude protein to give a 49% yield of the partially purified enzyme, with a final specific activity of 32 Umg-1 proteins. There was also a positive indication of sorghum catalase presence on SDS PAGE with positive bands occurring between the range of 48-62 kDa. Therefore, the molecular weight of sorghum catalase most likely falls within the two bands. The enzyme showed a narrow pH range with optimum activity occurring at pH 7. Similarly, its optimum activity temperature occurred at 40°C. This work is the first reported attempt at purifying catalase from sorghum.

Stimulus-Responsive Nanomedicines for Disease Diagnosis and Treatment

Stimulus-responsive drug delivery systems generally aim to release the active pharmaceutical ingredient (API) in response to specific conditions and have recently been explored for disease treatments. These approaches can also be extended to molecular imaging to report on disease diagnosis and management. The stimuli used for activation are based on differences between the environment of the diseased or targeted sites, and normal tissues. Endogenous stimuli include pH, redox reactions, enzymatic activity, temperature and others. Exogenous site-specific stimuli include the use of magnetic fields, light, ultrasound and others. These endogenous or exogenous stimuli lead to structural changes or cleavage of the cargo carrier, leading to release of the API. A wide variety of stimulus-responsive systems have been developed—responsive to both a single stimulus or multiple stimuli—and represent a theranostic tool for disease treatment. In this review, stimuli commonly used in the development of theranostic nanoplatforms are enumerated. An emphasis on chemical structure and property relationships is provided, aiming to focus on insights for the design of stimulus-responsive delivery systems. Several examples of theranostic applications of these stimulus-responsive nanomedicines are discussed.