Case Studies in Biogas Production from Different Substrates

The present paper involves applicative research in the field of biogas production with the accent on small laboratory scale installations built for biogas production, preliminary testing of substrate for biogas production and combustion applications for biogas-like mixtures. The interconnected aspect of the presented material involves cumulative expertise in multidisciplinary fields of interest and continuous development of possibilities to determine the energetic potential of substrates subjected to biodegradable fermentation conversion for further applications. The research analyzed the combustion behavior of biogas with different methane/carbon dioxide ratio without and in the presence of specific catalysts. Also, laboratory analysis on biomass substrates for determining their physical and chemical potential for different applications was performed. The main conclusions are drawn revolve around the untapped potential of the different types of biomasses that are not commonly used in the production of renewable energy carriers, like biogas, and also the potential use of residual biomass in combustion processes for an enclosed life cycle from cradle to the grave. The study involving the use of catalysts in biogas combustion processes present possible solutions which can be developed and implemented for increasing the combustion quality by using relatively cost-effective materials for the production of catalytic materials.

Methodology of asystolic donor heart’s condition study in an experiment using small laboratory animals

In transplantation, there has always been an acute problem of the discrepancy between the number of donor organs and the number of recipients, including donor hearts. There are various ways to increase the pool of donor organs, one of them is the use of asystolic or non-heart-beating donors. Due to poor myocardial tolerance of ischemia during the asystole period, as well as because of the difficulties in diagnosing cardiac diseases of the asystolic donor, which can be contraindication to transplantation. Therefore, an in-depth study of the state of the myocardium in asystolic donors is required. Currently, there is no generally accepted protocol for working with asystolic heart donors. This protocol should include methods of heart conditioning and assessing of myocardium state. For its development we need more experimental and preclinical studies. A protocol for such a study is proposed. The modeling of an asystolic donor using rats is described on the basis of experimental work carried out by a team of authors. The article describes the following technical aspects: anesthetic guidance, asystole detection criterion, maintaining the rat body temperature in accordance with the human body temperature during cardiac arrest, surgical aspects of performing the main experimental model. The Langendorff model of isolated cardiac perfusion was chosen as the main model for assessing the state of the myocardium of a small laboratory animal. Intra-left ventricular pressure, volume of coronary blood flow, heart rate and the presence of post-reperfusion arrhythmias were selected as criteria for assessing the state of donor hearts. Assessment of the volume of damage to the donor heart is carried out using triphenyltetrazolium chloride staining of the donor organ.

Grillz and Gold Teeth – Esthetic, Economics and Ethics

My laboratory has been providing services to a modest number of dental professionals for a while now. As part of prosthodontic work I have done, one has witnessed a generalised upsurge, albeit steady, in the request for gold inlays, followed by silver and grills overtime. The demand for these services is correlated with the location, period and ethos of the practice. Our practice has seen a drastic tapering down of requests during the Covid -19 period. Ultimately, there is a discernable driver for the demand of these services. We have also observed from dental casts that, the dentition appeared to be without any noticeable pathology. This implies that most patients requiring these prosthesis, have “virgin” teeth prepared. Being a small laboratory, our numbers, are insignificant compared to bigger laboratories. Additionally, unregistered laboratories and jewellers have entered this space and are providing ‘affordable’ alternatives. On a typical month, our laboratory fabricates a total of 320 prosthesis of which gold inlays, constitute about 60%, silver, 30% and grills, 10%. These numbers are an under-representation of the extent of this phenomenon and the potential ‘subdued’ and untapped market, especially during this fierce Covid -19 economic downturn. We hypothesise that we are witnessing the tip of an iceberg, and that under the right conditions, this grills and gold teeth epidemic will go beyond the tipping point. Given the cultural, economic and other factors, more and more youth will sustain the demand for these services in perpetuity.

Skin swabbing protocol to collect DNA samples from small-bodied fish species

Fish species are commonly used as experimental models in the laboratory. DNA is routinely collected from these animals to permit identification of their genotype. The current standard procedure to sample DNA is fin clipping, which involves anaesthetising individuals and removing a portion of the caudal fin. While fin clipping reliably generates good quality DNA samples for downstream applications, there is evidence that it can alter health and welfare, leading to infection and impacting on the fish’s behaviour. This in turn can result in greater variation in the data collected. In a recent study we adapted a skin swabbing protocol to collect DNA from small-bodied fish, including sticklebacks and zebrafish, without the use of anaesthetics or sharp instruments. A rayon-tipped swab was used to collect mucus from the flank of the fish, which was then used for DNA extraction. We subsequently demonstrated that compared to fin clipping, skin swabbing triggered fewer changes in stress axis activation and behaviour. We also found that data collected from fish that had been swabbed were less variable than data from fish that had been fin clipped, potentially allowing smaller sample sizes in experimental groups after using this technique, and thereby reducing animal use. Here we provide a detailed protocol explaining how to collect DNA samples from small laboratory fish using skin swabs.

New Approach for the Construction and Calibration of Gas-Tight Setups for Biohydrogen Production at the Small Laboratory Scale

Biohydrogen production in small laboratory scale culture vessels is often difficult to perform and quantitate. One problem is that commonly used silicon tubing and improvised plastic connections used for constructing apparatus are cheap and easy to connect but are generally not robust for gases such as hydrogen. In addition, this type of apparatus presents significant safety concerns. Here, we demonstrate the construction of hydrogen-tight apparatus using a commercially available modular system, where plastic tubing and connections are made of explosion-proof dissipative plastic material. Using this system, we introduce a gas chromatograph calibration procedure, which can be easily performed without necessarily resorting to expensive commercial gas standards for the calibration of hydrogen gas concentrations. In this procedure, the amount of hydrogen produced by the reaction of sodium borohydride with water in a closed air-filled bottle is deduced from the observed decrease of the oxygen partial pressure, using the ideal gas law. Finally, the determined calibration coefficients and the gas-tight apparatus are used for the analysis of simultaneous oxygen consumption and hydrogen production of the purple photosynthetic bacterium, Rhodospirillum rubrum, during semi-aerobic growth in the dark.

Development of the composition and technology of effervescent tablets for the prevention of cerebral circulation disorders in the elderly

Increasing the level of antioxidants in the human body plays an important role in increasing longevity. Studies on small laboratory animals showed that in the main group with an increased content of antioxidant enzymes, life expectancy was 20% higher than in the comparison group with age and heart diseases. Thus, the hypothesis is confirmed that a high content of active free radical molecules causes aging and the data obtained on small laboratory animals will increase the human lifespan. This fact is associated with the occurrence of heart and oncological diseases, as well as other age-related pathologies. In order to prevent the development of the above diseases, a drug was developed with an innovative composition of complex-compatible components. The experimental drug contains substances with an increased content of antioxidants for the prevention of cerebrovascular accidents, such as dihydroquercetin and black grape extract. And also vitamins and amino acids: succinic acid, ascorbic acid, glycine. The choice of the composition of the experimental drug was carried out on the basis of the antioxidant properties of these groups of substances, which are widely known, and their combined use will become a potentiated synergy of the selected components and complement their effect. Due to the fact that the classical technology for the production of effervescent dosage forms does not allow combining the components of the composition of the experimental drug, the task of developing an individual technology for combining the acid and alkaline fractions of the formulation by separating the components at the stage of the technological process of drying the raw material was solved. Thanks to this, it became possible to separate the granulation of acid and alkaline components, which made it possible to stabilize the tabletting mixture (3 tables, bibliography: 8 refs.).

Professor Kudrevetski Vasily Vasilievich — Little Known Biography Facts

The scientist’s professional activities were associated with the Imperial University of Warsaw, where he headed the department of the faculty therapeutic clinic (1895-1910), was the dean of the medical faculty and acting as the rector (1909-1910). Professor Kudrevetski V.V. was a scholar of an outstanding scientist, academician Pavlov I.P. Under his leadership in a small laboratory of the prof. S.P. Botkin clinic, they carried out the first fundamental research and experimental work on the physiology of digestion. The accumulated experience on this topic allowed Kudrevetski to defend his doctoral dissertation in 1890, the scientific consultant of which was Ivan Petrovich himself. The results of fundamental works of V.V. Kudrevetski formed the basis of scientific ideas about the physiology of the digestive system and have not lost their relevance today.