New developments of the effect of melatonin on reproduction

In the past decades, a lot of advances in understanding the biochemistry and physiology of the pineal gland have been made. There is evidence that it interacts with many endocrine as well as non-endocrine tissues to influence their metabolic activity modulating many organs and functions. Melatonin is secreted by the pineal gland in the brain and plays an important role in regulating the neuroendocrine system. This hormone is one of the major role players in the regulation of the circadian sleep-wake cycle. It is normally released from the pineal gland during the night in response to environmental changes in light. Studies have shown that melatonin plays a role in the regulation of many reproductive processes such as puberty, gonadal function, and pregnancy. Beside these, melatonin has been shown to be able to directly neutralize a number of free radicals and reactive oxygen and nitrogen species. The main objective of this review is to provide comprehensive information about the new developments in melatonin research regarding its role in reproduction. A review of international scientific literature was done and a question-and-answer format was used in an attempt to convey comprehensive information in a simple manner. This review discusses evidence currently available relating to the effect of melatonin on reproductive processes. It deliberates the mechanism of action of melatonin, its effect on puberty, testicular and ovafunction, pregnancy, and oxidative stress. A growing body of scientific evidence is suggesting that melatonin plays an important role in reproductive function. It is therefore imperative to highlight the beneficial effects of this hormone in improving the reproductive processes.

非化学修饰的药物靶点发现技术在中药研究中的应用

中医药是我国的科学与文化瑰宝,具有数千年的临床用药经验。中医药在复杂疾病及慢性疾病防治方面具有显著优势,在当前全球肆虐的新型冠状病毒肺炎(corona virus disease 2019,COVID-19)防治中也彰显了其优势,但由于作用机制不清楚等问题严重限制了其推广应用。化学药治疗疾病作用机制明确,具有成熟的药物靶点发现技术,主要包括化学修饰技术和非化学修饰技术。中药具有多成分、多靶点的作用特点,应用化学修饰技术进行作用靶点的研究具有一定的局限性。因此,主要介绍细胞热位移分析、分子对接技术、药物亲和反应的靶点稳定性和表面等离子共振技术等非化学修饰的药物靶点发现技术的原理、操作流程和应用,并对其在中药作用机制研究中的潜在优势与不足进行讨论,以期探索出一种中药作用靶点发现模式,为中药作用机制的阐明提供参考与借鉴,助推中医药现代化进程。

Development and Validation of Proximal Chemistry Analytical Procedure in Semi-automated Equipment

The proximal chemical analysis （AQP） includes 5 fundamental tests, which are： determination of crude protein, determination of crude fiber, determination of humidity, determination of ashes and determination of fat. This last determination can be made in two different ways, which will depend on the type of sample being treated, as well as the amount of fat expected to be obtained in the food to be analyzed. For foods with low amounts of fat the hydrolysis technique is used, which is divided into 3 phases. All the methods before being taken to the daily practice in a laboratory of food analysis either internal control, verification or third authorized must be validated, in order to obtain consistent, robust and reliable results. In those cases in which the method that will be tested differs with the method that is reported in the literature, a comparison of both methods should be made in order to ensure that both are compatible and the results will be equally reliable. In the validation, the acceptance parameters will be established for each one of the tests that are carried out in it, while at the end of it the acceptance criteria for the general method will be established. The objective of this work was to carry out the development of analytical methodology that was validatable in order to reduce analysis time by using semi-automated equipment. In the case of semi-automated equipment, this comparison of methods is carried out, as it was the case of the analysis of fat with hydrolysis, which used a hydrolysis unit and the extraction equipment using samples of finished food for animal consumption. The results obtained in the validation using the traditional method correspond to a CV less than 2%, while the results obtained using semi-automated equipment correspond to a CV less than 2% for the case of fat determination with hydrolysis.

Opportunities and Challenges for the Development of Green Detergents

The characteristic of green detergents and it＇s difference with regular detergent was expounded in this paper, according to the kernel of green chemistry. The variation trends of Chinese mainstream consumer group show that the new mainstream consumer group are concerning more and more about household detergent, especially its safety to human and environment. Growing attention of the mainstream consumer group and the standard drafting units on detergent will promote the development of green detergents, however, there are still challenges for the development of green detergents.

The influence of the mass culture on the contemporary college students＇ daily life

The mass culture penetrates into the world of the daily life of the contemporary college students in all directions. As the most sensitive group of the cultural assimilation, the college students practice various forms of the mass culture in their daily life. The popular culture and the everyday life are inseparable. The mass culture influences and changes the concept of our everyday life and the practice of our daily life, and enriches the connotation of the popular culture. The popular culture greatly enriches and expands the daily life of the college students with the features of the image, the nationhood and the consumption, but it also brings the negative effects that cannot be ignored. The daily life of the college students can be divided into several relative meanings according to their contents and forms, including the communication plate, the emotional plate and the leisure plate. Every meaning plate is concerned about the generation of values in the daily life of the college students, and the mass culture gives fresh and complicated contents to these meanings. How to find the values of their life and how to present oneself is the difficult problems and missions faced by the contemporary college students.

Acoustic Valve Integration in Exhaust Line Systems

In recent years the demand for the acoustic performance of exhaust systems has increased and will further increase in the future. The main drivers are new pass-by-noise regulation and new powertrain technologies paired with exhaust muffler volume, weight and costs constraints. In the following paper several application examples for Adaptive ValveTM （self-actuated in-pipe valve）, in-muffler valve and electric valve are shown and the related benefits on the system performance are assessed. It is shown that implementing a valve into an exhaust system has a significant influence on the NVH performance. The resulting backpressure penalties can be minimized using the right implementation strategy of the valves in the exhaust system. Hence the exhaust system has to be specifically designed for the integration of a valve. All three valve types have additional benefits to their standard application for overall noise reduction and muffler volume reduction, which are analyzed. The Adaptive ValveTM, for example, is often used on cars with long pipe routing and has the additional benefit of reducing pipe resonance in the system. Another example, the electric valve, can be coupled with vehicle communication networks and hence the flexibility in application is significantly increased.

Analysis of the coated and textured ring/liner conjunction based on a thermal mixed lubrication model

For the ring/liner conjunction, well‐designed surface texturing has been regarded as a potential means to improve its tribological performance, as well as the application of coating. However, so far most researchers focused on the one of these aspects. In this study, the combined effect of coating and texturing on the performance of ring/liner conjunction is numerically investigated. A thermal mixed lubrication model is presented. The effects of the coating's thermal and mechanical properties on the tribological performance are studied under the cold and warm engine operating conditions. Along with the increasing coating thickness, the effects of the coating's thermal properties on friction loss are found to be significant, as well as the effects of the coating's mechanical properties. It is also found that a soft coating with a lower thermal inertia has a greater ability to reduce the friction loss of the textured conjunction.

Inspirations from the scientific discovery of the anammox bacteria: A classic example of how scientific principles can guide discovery and development

Anaerobic ammonium oxidation(anammox) is a relatively new pathway within the N cycle discovered in the late 1990 s. This eminent discovery not only modified the classical theory of biological metabolism and matter cycling, but also profoundly influenced our understanding of the energy sources for life. A new member of chemolithoautotrophic microorganisms capable of carbon fixation was found in the vast deep dark ocean. If the discovery of the chemosynthetic ecosystems in the deep-sea hydrothermal vent environments once challenged the old dogma "all living things depend on the sun for growth," the discovery of anammox bacteria that are widespread in anoxic environments fortifies the victory over this dogma. Anammox bacteria catalyze the oxidization of NH_4^+ by using NO_2^- as the terminal electron acceptor to produce N_2. Similar to the denitrifying microorganisms, anammox bacteria play a biogeochemical role of inorganic N removal from the environment. However, unlike heterotrophic denitrifying bacteria, anammox bacteria are chemolithoautotrophs that can generate transmembrane proton motive force, synthesize ATP molecules and further carry out CO_2 fixation through metabolic energy harvested from the anammox process. Although anammox bacteria and the subsequently found ammonia-oxidizing archaea(AOA), another very important group of N cycling microorganisms are both chemolithoautotrophs, AOA use ammonia rather than ammonium as the electron donor and O_2 as the terminal electron acceptor in their energy metabolism. Therefore, the ecological process of AOA mainly takes place in oxic seawater and sediments, while anammox bacteria are widely distributed in anoxic water and sediments, and even in some typical extreme marine environments such as the deep-sea hydrothermal vents and methane seeps. Studies have shown that the anammox process may be responsible for 30%–70% N_2 production in the ocean. In environmental engineering related to nitrogenous wastewater treatment, anammox provides a new technology with low energy consumption, low cost, and high efficiency that can achieve energy saving and emission reduction. However, the discovery of anammox bacteria is actually a hard-won achievement. Early in the 1960 s, the possibility of the anammox biogeochemical process was predicted to exist according to some marine geochemical data. Then in the 1970 s, the existence of anammox bacteria was further predicted via chemical reaction thermodynamic calculations. However, these microorganisms were not found in subsequent decades. What hindered the discovery of anammox bacteria, an important N cycling microbial group widespread in hypoxic and anoxic environments? What are the factors that finally led to their discovery? What are the inspirations that the analyses of these questions can bring to scientific research? This review article will analyze and elucidate the above questions by presenting the fundamental physiological and ecological characteristics of the marine anammox bacteria and the principles of scientific research.

Chemical and structural biology of nucleic acids and protein-nucleic acid complexes for novel drug discovery

Since nucleic acids(DNA and RNA) play very important roles in cells,they are molecular targets of many clinically used drugs,such as anticancer drugs and antibiotics.Because of clinical demands for treating various deadly cancers and drug-resistant strains of pathogens,there are urgent needs to develop novel therapeutic agents.Targeting nucleic acids hasn’t been the mainstream of drug discovery in the past,and the lack of 3D structural information for designing and developing drug specificity is one of the main reasons.Fortunately,many important structures of nucleic acids and their protein complexes have been determined over the past decade,which provide novel platforms for future drug design and discovery.In this review,we describe some useful nucleic acid structures,particularly their interactions with the ligands and therapeutic candidates or even drugs.We summarize important information for designing novel potent drugs and for targeting nucleic acids and protein-nucleic acid complexes to treat cancers and overcome the drug-resistant problems.