High Sensitivity Mass Spectrometric Quantification of Serum Growth Hormone by Amphiphilic Peptide Conjugation

Amphiphilic peptide conjugation affords a significant increase in sensitivity with protein quantification by electrospray-ionization mass spectrometry. This has been demonstrated here for human growth hormone in serum using N-(3-iodopropyl)-N,N,N-dimethyloctylammonium iodide (IPDOA-iodide) as derivatizing reagent. The signal enhancement achieved in comparison to the method without derivatization enables extension of the applicable concentration range down to the very low concentrations as encountered with clinical glucose suppression tests for patients with acromegaly. The method has been validated using a set of serum samples spiked with known amounts of recombinant 22 kDa growth hormone in the range of 0.48 to 7.65 \mug/L. The coefficient of variation (CV) calculated, based on the deviation of results from the expected concentrations, was 3.5% and the limit of quantification (LoQ) was determined as 0.4 \mug/L. The potential of the method as a tool in clinical practice has been demonstrated with patient samples of about 1 \mug/L

Effective Strategies for Mitigating Bidding Corruption for U.S. Infrastructure Contracts

Fraud in the U.S. government and corporate construction bidding process remains a critical issue, driving up project costs, distorting competition, and undermining financial forecasting. Business owners face financial losses and competitive disadvantages due to fraudulent bidding, while regulators struggle to enforce fair practices, and taxpayers bear the burden of inflated costs. Grounded in the fraud triangle theory, the purpose of this qualitative multiple-case study was to explore successful strategies to mitigate fraud in the government and corporate construction bidding process. The participants were 10 construction managers from the Department of Transportation, Department of Justice, and private sector, all experienced in fraud mitigation. Data were collected through face-to-face semistructured interviews, historical data, and publicly available documents. Through thematic analysis, six primary themes emerged: psychological and cultural factors contributing to unethical behavior, oversight gaps in existing controls, the role of technology in enhancing transparency and reducing fraud, the impact of ethics training on accountability, the necessity of rotating evaluators and external audits to mitigate bias, and the importance of rationalizing prevention through a strong ethical culture. A key recommendation is for Department of Transportation leaders to enhance internal controls using state-of-the-art auditing technology to improve transparency in the bidding process, which is pivotal to creating an ethical organizational culture. The potential implications for positive social change include improving the quality and efficiency of public infrastructure projects and minimizing abuse of taxpayer funds

Correct quantitative determination of ethanol and volatile compounds in alcohol products

Determination of the volume content of ethanol in the alcohol products in practice is usually determined by pycnometry, electronic densimetry, or densimetry using a hydrostatic balance in accordance with Commission Regulation No 2870/2000. However, these methods determine directly only density of the tested liquid sample and does not take into account the effects of other volatile components such as aldehydes, esters and higher alcohols. So they are appropriate only for binary water-ethanol solutions in accordance with international table adopted by the International Legal Metrology Organization in its Recommendation No 22. Availability notable concentrations of the higher alcohols and ethers in different alcohol-based products, e. g. in whisky, cognac, brandy, wine as well as in waste alcohol and alcohol beverage production, leads to the significant contribution of these compounds in the value of the density of tested alcohol-containing sample. As a result, determination of the volume of ethanol content for such alcohol products in gives the value of the strength, which may significantly differ from the true one. Using incorrectly calculated volume content of ethyl alcohol leads to incorrect results determining the quantities of volatile compounds in the alcohol-containing products, expressed in milligrams per liter of absolute alcohol. We propose experimental results of the method of correct determination of ethanol and other volatile compounds content in waste products of alcohol and alcoholic beverage industry by gas chromatography. Calculations are based on the measured value of sample density and volatile compound concentrations expressed in mg per liter of absolute alcohol [JAFC 61(2013)2950]. The method can be easily incorporated into daily practice of analytical and control laboratories with no additional material, financial or time costs.Comment: 4 pages, 2 figures, submitted to Proc. of the Wine Active Compounds (WAC) 2014 international conference (Beaune, France, March 26-28, 2014

Kinetics of diffusion interaction in the Ti-NiCr system layered composites

The results of investigation of the diffusion interaction kinetics at the boundary of explosion welded Ti-NiCr system compositions during heat treatment are presented. The structure, chemical and phase composition of the formed diffusion zones are also studied. It is shown that the layered diffusion zone is formed at a temperature below the eutectoid transformation. Diffusion zone consists of solid solutions based on Ti2Ni, TiNi, and TiNi3 intermetallic compounds, as well as chromium-based solid solution inclusions along the boundary with the NiCr alloy. An increase in temperature above the eutectoid transformation leads to an intensification of the growth of the diffusion zone and the diffusion of nickel into the titanium alloy with the formation of a eutectoid structure in it. The use of alloyed titanium alloys instead of commercially pure titanium does not affect the phase composition of the formed diffusion zones, but slows down the diffusion processes

Aluminizing of the EP648 alloy by hot-dipping

The structure and phase composition of coatings formed on the surface of the EP648 alloy were studied using the hot-dip aluminizing method with subsequent heat treatment. Aluminizing allows one to form a continuous aluminide coating with a clearly distinguishable layered structure, in which the upper layer is represented by (Al) with eutectic inclusions, the middle layer consists of (Al) and intermetallics mixture, and the thin boundary layer has a φ + κ / φ / Ni2Al3(Cr) structure. Treatment of the aluminized EP648 alloy at 1100 °C allows one to get rid of the (Al) phase and form an intermetallic coating due to the diffusion redistribution of chemical elements