An Original Approach to Measure Ligand/receptor Binding Affinity in Non-purified Samples

Several biochemical and biophysical methods are available to determine dissociation constants between a biological target and its ligands. Most of them require purification, labelling or surface immobilisation. However, these measurements remain challenging concerning membrane proteins because purification requires their extraction from the native lipid environment using different approaches, a process that may impact receptor conformation and functionality. We have developed a novel experimental procedure to determine binding affinities of a ligand to a membrane protein, the dopamine D2 receptor (D2R), directly from cell membrane fragments, using microscale thermophoresis (MST). Two main challenges had to be overcome: to determine the concentration of dopamine D2R in the crude sample; to find ways to minimize or account for non-specific binding of the ligand to cell fragments. Using MST, we were able to determine the D2R concentration in cell membrane fragments to be about 36.8 ± 2.6 pmol/mg. Then titration curves allowed the determination of a KD about 5.3 ± 1.7 nM, that is very close to the reported value. Important details of the experimental procedure are detailed to allow the transposition of this novel method to various membrane proteins.

HAND BOOK ON PRACTICAL MICROBIOLOGY

Hand book of Practical Microbiology, is a performance based text designed for use by students of microbiology, biotechnology, medicine, laboratory technology, allied sciences; by microbiologists and by others who are interested in practical microbiology. The intent of the book is to provide recent information and explain in detail the routine microbiological methods performed in a Microbiology laboratory. Hand book of Practical Microbiology consists of 12 chapters. Each chapter contains practical exercises. Each exercise contains theoretical aspects of the practical, principle, and experimental procedure in detail.

Advances in Forensic Geochemistry

This chapter is meant to give the state of the art of forensic geochemistry and recent advances. In terms of forensic organic geochemistry, detecting mature organic matter including polluting hydrocarbons follows an experimental procedure by using recent experimental analytical techniques. However, the interpretation of these results needs an understanding of the geochemical context to make a distinction between the natural and the human made origin of oil. Infrared data coupled with statistical analyses would have an important relevance for the detection of the pollution during the Anthropocene, which is marked an increasing human pollution reaching the level of environmental crimes. In terms of nuclear and isotopic forensic geochemistry, recent studies provided that nuclear forensics considers the fact that some measurable parameters or signatures are distinctive.

Experimental Methodology to Determine Thermal Conductivity of Nanofluids by Using a Commercial Transient Hot-Wire Device

The lack of a standard experimental procedure to determine thermal conductivity of fluids is noticeable in heat transfer processes from practical and fundamental perspectives. Since a wide variety of techniques have been used, reported literature data have huge discrepancies. A common practice is using manufactured thermal conductivity meters for nanofluids, which can standardize the measurements but are also somewhat inaccurate. In this study, a new methodology to perform reliable measurements with a recent commercial transient hot-wire device is introduced. Accordingly, some extensively studied fluids in the literature (water, ethylene glycol, ethylene glycol:water mixture 50:50 vol%, propylene glycol, and n-tetradecane) covering the range 0.100 to 0.700 W m−1 K−1 were used to check the device in the temperature range 283.15 to 333.15 K. Deviations between the collected data and the theoretical model, and repeatabilities and deviations between reported and literature values, were analyzed. Systematic deviations in raw data were found, and a correction factor depending on the mean thermal conductivity was proposed to operate with nanofluids. Considering all tested effects, the expanded (k = 2) uncertainty of the device was set as 5%. This proposed methodology was also checked with n-hexadecane and magnesium-oxide-based n-tetradecane nanofluids.

Biodiesel-Alkaline Transesterification Process for Methyl Ester Production

The world needs to increase renewable and alternative fuel sources such as Biomass, Bioethanol, and Biodiesel to compete with fossil fuels. Biodiesel is an important renewable fuel source since it can be used in regular diesel vehicles without requiring engine modifications. Conventional biodiesel production takes around 90 min of reaction time. A longer reaction time is not suitable for commercial production. Furthermore, traditional products such as oil react with biodiesel methoxide to produce a maximum of 90% biodiesel yield. As the catalyst is not involved with the reaction, pure methanol and methoxide (methanol with KOH catalyst) are separately added to the system to enhance the pre-reaction step. By changing the methanol to methoxide ratio, biodiesel is produced, and yield is calculated. The highest yield, which is 95%, is obtained with a 5:15% methanol to methoxide ratio. The total reaction time with the new experimental procedure is only 20 min. That is a significant reduction by saving operating costs such as energy consumption. Produced biodiesel show similar properties to that of standard biodiesel.

European Union as a Set of New Values in State-Building Processes in EU Enlargement Candidate Countries

The aim of the research was to analyze the latest values of the EU in the context of their adaptation in the process of state-building in the candidate countries for enlargement with a view to reforming the legal field of the States. The main method was the observation method as a component of the experimental procedure with subsequent interpretation of the results (description). The results of the study demonstrate the axiological importance of the EU’s main values. At the same time, the need for a gradual implementation of reforms in the sphere of state-building is argued, given the desirability of preserving national identity. It is concluded that the low level of adaptation of the EU pyramid of core values is corroborated and confirmed by statistical data, which requires a qualitative transformation of the reform strategy of the state-building processes of the candidate countries for EU enlargement. Scientific research was concerned with the search for the optimal and effective concepts of the integrated application of European values in the state-building processes in the candidate countries for EU enlargement.

Experimental and Numerical Investigation of Contact Parameters in a Dovetail Type of Blade Root Joints

this paper focuses on the contact characteristics of the blade root joints subjected to the dry friction damping under periodic excitation. The numerical method and experimental procedure are combined to trace the contact behavior in the nonlinear vibration conditions. In experimental procedure, a novel excitation method alongside the accurate measurements is used to determine the frequencies of the blade under different axial loads. In numerical simulations, local behavior of contact areas is investigated using the reduction method as a reliable and fast solver. Subsequently, by using both experimental measurements and numerical outcomes in a developed code, the global stiffness matrix is calculated. This leads to find the normal and tangential stiffness in the contact areas of a dovetail blade root joints. The results indicate that the proposed method can provide an accurate quantitative assessment for investigation the dynamic response of the joints with focusing the contact areas.

Biorefinery Cascade Processing For Converting Corncob To Xylooligosaccharides And Glucose By Maleic Acid Pretreatment

Corncob as an abundance and low-cost waste resource has received increasing attention to produce value added chemicals, it is rich in xylan and regarded as the most preferable feedstock for preparing xylooligosaccharides, which possesses highly commercial value due to a range of health benefits. The strategy with xylooligosaccharides as core products can cut costs and improve economic efficiency of biorefinery. Therefore, a cascade processing for converting corncob to xylooligosaccharides and glucose by sequential maleic acid pretreatment and enzymatic hydrolysis was design. Based on overarching aim of this study that maximally yielding xylooligosaccharides, corncob was first subjected to response surface methodology experimental procedure for optimizing the conditions. Correspondingly, a maximum xylooligosaccharides yield of 52.9% was achieved with 0.5% maleic acid at 155 °C for 26 min. Maleic acid, a non-toxic and edible catalyst, was able to effectively hydrolyze xylan into xylooligosaccharides and simultaneously generate a positive pretreated effect for improve the enzymatic hydrolysis efficiency. Finally, an enzymatic hydrolysis yield of 87.5% was achieved from maleic acid-treated corncob at 10% solids loading. This cascade processing may provide a novel strategy for the other biomass wastes utilization.

Prediction of Aggregate Impact Values and Aggregate Crushing Values Using Light Compaction Test

Crushing test and Impact test are very important to estimate strength and toughness characteristics of the road aggregate. Extensive experimental procedures and different sets of equipment are required for these types of aggregate testing. Therefore, the objective of the study is to investigate whether the light compaction test can be a suitable alternative for both these tests. For this experimental procedure, 60 aggregate samples were collected from different rock quarries spread along North-eastern states of India. The specifications of the aggregate samples are kept similar for all of these three test procedures. The result indicates a strong correlation of Light compaction values (LCV) with Aggregate crushing values (ACV) and Aggregate Impact Values (AIV). The R2 values for the relationship was found to be more than 0.9 for both these relationships. It indicates that the LCV can be used to closely predict the ACV and AIV. The root mean square error (RMSE) values estimated based on the actual and predicted values were also found to be low which further concrete the claim that light compaction test can be a suitable alternative for crushing test and impact test of the aggregates.