Methods for the Determination of Stable Isotopes of Carbon and Nitrogen Directly in Valine, Proline, Glutamine, and Glutamic Acid

Amino acids are very important compounds for the body and are involved in important functions that keep us healthy. Amino acids are essential components such as valine, proline, glutamine and glutamic acid. They can be synthesized either naturally or artificially. To examine the metabolism and regulate the synthesis process, compounds labeled with nitrogen or carbon isotopes need to be used. These isotopic compounds allow for more extensive research and enable studies that would otherwise be impossible. However, their use is dependent on the availability of simple, efficient methods for isotopic analysis. Currently, the determination of the atomic fraction of carbon and nitrogen isotopes is only possible through their conversion into molecular nitrogen or carbon monoxide or carbon dioxide. This leads to the loss of information about isotopic enrichment in specific centers of the molecule. This article explores a new direct approach to determining the atomic fraction of carbon and nitrogen isotopes in the isotope-modified or identical centers of these compounds. This method eliminates the transfer process and dilution due to nitrogen and carbon impurities. It is now possible to simultaneously determine the atomic fraction of nitrogen and carbon isotopes in the research substance. This method can be applied to amino acids, making it an effective tool for proposing new research methods. Several articles [1] [2] [3] have proposed similar methods for organic compounds and amino acids.

Determination of Carbon and Nitrogen Isotope Fractions in Tartaric Acid, Oxalic Acid, Glucose and Fructose—National Center of High Technologies of Georgia

Tartaric acid, oxalic acid, glucose, and fructose are highly important compounds. A comprehensive study of these substances is fascinating from a scientific perspective. They are key components found in wine, vegetables, and fruits. Understanding the isotopic compositions in organic compounds is crucial for comprehending various biochemical processes and the nature of substances present in different natural products. Tartaric acid, oxalic acid, glucose, and fructose are widely distributed compounds, including in vegetables and fruits. Tartaric acid plays a significant role in determining the quality and taste properties of wine, while oxalic acid is also prevalent but holds great interest for further research, especially in terms of carbon isotopic composition. We can unveil the mechanisms of processes that were previously impossible to study. Glucose and fructose are the most common monosaccharides in the hexose group, and both are found in fruits, with sweeter fruits containing higher amounts of these substances. In addition to fruits, wheat, barley, rye, onions, garlic, lentils, peppers, dried fruits, beans, broccoli, cabbage, tomatoes, and other foods are also rich sources of fructose and glucose. To determine the mass fraction of the carbon-13 isotope in these compounds, it is important to study their changes during natural synthesis. These compounds can be modified with a carbon center. According to the existing isotopic analysis method, these compounds are converted into carbon oxide or dioxide [1]. At this point, the average carbon content in the given compound is determined, but information about isotope-modified centers is lost. Dilution may occur through the transfer of other carbon-containing organic compounds in the sample or by dilution with natural carbon or carbon dioxide during the transfer process. This article discusses the possibility of carbon-13 isotope propagation directly in these compounds, both completely modified and modified with individual carbon centers. The literature provides information on determining carbon-13 substance in organic compounds, both with a general approach and for individual compounds [2] [3].

Genetic Variation Assessed with Microsatellites in Mass Selection Lines of the Pacific Oyster (Crassostrea gigas) in China

Abstract Four successive mass selection lines of the Pacific oyster, Crassostrea gigas, selected for faster growth in breeding pro- grams in China were examined at ten polymorphic microsatellite loci to assess the level of allelic diversity and estimate the effective population size. These data were compared with those of their base population. The results showed that the genetic variation of the four generations were maintained at high levels with an average allelic richness of 18.8-20.6, and a mean expected heterozygosity of 0.902-0.921. They were not reduced compared with those of their base population. Estimated effective population sizes based on temporal variances in microsatellite frequencies were smaller to that of sex ratio-corrected broodstock count estimates. Using a rela- tively large number ofbroodstock and keeping an equal sex ratio in the broodstock each generation may have contributed to retaining the original genetic diversity and maintaining relatively large effective population size. The results obtained in this study showed that the genetic variation was not affected greatly by mass selection progress and high genetic variation still existed in the mass selection lines, suggesting that there is still potential for increasing the gains in future generations of C. gigas. The present study provided im- portant information for future genetic improvement by selective breeding, and for the design of suitable management guidelines for genetic breeding of C. gigas.

Minimizing Makespan on Mixed Mass Production Lines of Two and Three Machines

The objective of the research discussed in this paper has been to find an optimal schedule on mixed mass production lines of two and three machines. Johnson's rule on flow shops is generalized to mixed mass production lines. Scheduling methods on three-machine lines are proposed for six special kinds of data of processing times of jobs. The scheduling method on two-machine lines is also proposed.

On the central symmetry of the circumstellar envelope of RS Cnc

We present a phenomenological study of CO（1-0） and CO（2-1） emission from the circumstellar envelope （CSE） of the Asymptotic Giant Branch （AGB） star RS Cnc. It reveals departures from central symmetry that turn out to be efficient tools for the exploration of some of the properties of the CSE. We use a wind model including a bipolar flow with a typical wind velocity of ～8 km s^-1 that decreases to ～2 km s^-1 near the equator. This wind model is used to describe Doppler velocity spectral maps obtained by merging data collected at the IRAM Plateau de Bure Interferometer and Pico Veleta single dish radio telescope. Parameters describing the wind morphology and kinematics are obtained, together with the radial dependence of the gas temperature in the domain of the CSE probed by the CO observations. Significant north-south central asymmetries are revealed by the analysis, which we quantify using a simple phenomenological description. The origin of such asymmetries is unclear.

Beyond an Elegant Political Slogan： Reading the Mass Line through the Lens of Methods

The mass line （ML） played a significant role in the history of the Communist Party of China （CPC） and was incorporated into the CPC＇s Constitution as the fundamental line for all work. However, to most people, the ML would sound more like an elegant political slogan than an effective method for solving problems. This paper interprets the essence of the ML as a philosophical method of knowing the world, a political method of leadership and a practical method of solving problems. In the new era of rule of law, the ML is also considered as a potential approach to democracy in China. The paper also criticizes the problems of the ML and proposes some suggestions against the comparison with the Western political systems. The paper will provide readers with a more comprehensive understanding of the ML, and the political philosophy in China.

The History of the CPC Is a History of the Shaping and Improvement of Its Mass Line

The history of the Party is a history in which the Party led the people to fight with the domestic and foreign enemies to achieve national and social liberation, and also a history in which the Party gradually established and deepened its flesh-and-blood ties with the people and shaped and improved its mass line. Without the support of the Chinese people, there would be no Communist Party of China. The people has always been root of the Party＇s survival and development, and the mass line has permeated into all aspects of the Party＇s lines, principles and policies, thus becoming the Chinese Communists＇ feelings and beliefs deep into the soul, their culture, ethics, ways of thinking, lifestyle, and driving force and lifeline.

Wengongtuan and the Rural Literary Popularization Movement in Yan＇an

This paper takes the folk song collection movement in Yan＇an as an example to examine the role of the wengongtuan （The League of Literary and Artistic Workers） in organizing the rural literary popularization movement in the 1940s. Dispatched by the Communist Party of China （CPC）, wengongtuan members took on the task of mobilizing peasants into cultural production, and realized a self-reconstruction in the process of integrating themselves into the lives of revolutionary peasants. The idea of the wengongtuan derived from the CPC＇s theory of the mass line--＂from the masses and to the masses＂--which laid the foundation of New Democratic culture in the 1940s.

Incorporating Civil Society： China＇s NGO Strategy

During the Chinese Communist Revolution, Mao Ze-dong developed and used the mass hne to link the top leaders of the Chinese Communist Party（CPC） with the masses. Atier 1949, the mass line mechanism fell into disuse; but in today＇s China, there seems to be a trend toward more openness. Deng-era reforms have decentralized the central government, weakened adherence to Party ideology, and reduced the state＇s control. In order to deal with diversified social interests, the CPC is renewing and extending the practice of the mass line through state-liceused intermediate organizations. By doing so, the central government is not only creating a channel for interest articulation but also deepening state control and regulation of civil society to ensure that power remains largely centralized.