Effect of Soyabean Isoflavones Exposure on Onset of Puberty, Serum Hormone Concentration and Gene Expression in Hypothalamus, Pituitary Gland and Ovary of Female Bama Miniature Pigs

This study was to investigate the effect of soyabean isoflavones (SIF) on onset of puberty, serum hormone concentration, and gene expression in hypothalamus, pituitary and ovary of female Bama miniature pigs. Fifty five, 35-days old pigs were randomly assigned into 5 treatment groups consisting of 11 pigs per treatment. Results showed that dietary supplementation of varying dosage (0, 250, 500, and 1,250 mg/kg) of SIF induced puberty delay of the pigs with the age of puberty of pigs fed basal diet supplemented with 1,250 mg/kg SIF was significantly higher (p<0.05) compared to control. Supplementation of SIF or estradiol valerate (EV) reduced (p<0.05) serum gonadotrophin releasing hormone and luteinizing hormone concentration, but increased follicle-stimulating hormone concentration in pigs at 4 months of age. The expression of KiSS-1 metastasis-suppressor (KISS1), steroidogenic acute regulatory protein (StAR) and 3-beta-hydroxysteroid dehydrogenase/delta-5-delta-4 isomerase (3β-HSD) was reduced (p<0.01) in SIF-supplemented groups. Expression of gonadotropin-releasing hormone receptor in the pituitary of miniature pigs was reduced (p<0.05) compared to the control when exposed to 250, 1,250 mg/kg SIF and EV. Pigs on 250 mg/kg SIF and EV also showed reduced (p<0.05) expression of cytochrome P450 19A1 compared to the control. Our results indicated that dietary supplementation of SIF induced puberty delay, which may be due to down-regulation of key genes that play vital roles in the synthesis of steroid hormones

Development of New Organic Photoredox Catalysis Driven by Visible Light

Development of efficient and sustainable synthetic technologies for molecular construction is the central goal in modern organic synthesis. In recent decades, organocatalysis has become one of the viable tools in organic synthesis with notable features including easy manipulation, low cost, and/or less susceptible to air and moisture. Organophotoredox catalysis has merged as a front runner in organocatalysis. My Ph.D. study focuses on the development of novel visible-light mediated organic photoredox catalysis strategies for the construction of structurally diverse molecular architectures in distinct ways. In the first efforts, a metal- and oxidant-free organophotocatalytic method for preparing structurally diverse thioesters from readily accessible, abundant aldehydes, has been realized. Excited by blue light, the simple and cost-effective 9,10-phenanthrenequinone (PQ) promotes hydrogen atom transfer (HAT) to selectively generate acyl radicals from corresponding aldehydes without inducing crossover reactivity of thioesters. In situ formed acyl radicals then react with thiosulfonate S-esters to efficiently produce thioesters. The mild and efficient method exhibits excellent substrate scope and outstanding functional group tolerance. Significantly, it is proved to be useful in a late-stage functionalization of complex molecules. Direct H/D exchange at formyl groups represents the most straightforward approach to C-1 deuterated aldehydes. Along this line, a new photoredox catalytic, visible-light mediated neutral radical approach has been developed via a unique double-HAT process. Selective control of highly reactive acyl radical enables driving the formation of deuterated products when an excess of D2O is employed. The power of H/D exchange process has been demonstrated for both aromatic aldehydes and aliphatic substrates, and more important late-stage deuterium incorporation into complex structures with uniformly high deuteration level (>90%). The direct dearomatization of indoles represents the most straightforward access to indolines. However, the exiting dearomative methods largely restrict to electron-rich indoles or go through an ionic process using strong nucleophiles. Toward this end, an unprecedented organophotocatalytic process by harnessing nucleophilic radicals to react with electron-deficient indoles was developed. The preparative power of this radical-engaged strategy has been demonstrated by direct addition of in situ formed nucleophilic radicals from readily accessible feedstock carboxylic acids, into structurally diverse electrophilic indoles including (thio)ester, amide, ketone, nitrile and thus delivering a series of trans-2,3-disubstituted indolines with uniformly high stereoselectivity (> 20:1 dr). Moreover, this approach has also been successfully applied to other aromatic heterocycles such as pyrroles, benzofurans and benzothiophenes.Release after 11/14/202

Developing an IoT-Enabled Cloud Management Platform for Agricultural Machinery Equipped with Automatic Navigation Systems

Smart farming uses advanced tools and technologies such as intelligent agricultural machines, high-precision sensors, navigation systems, and sophisticated computer systems to increase the economic benefits of agriculture and reduce the associated human effort. With the increasing demands of individualized farming operations, the internet of things is a crucial technique for acquiring, monitoring, processing, and managing the agricultural resource data of precision agriculture and ecological monitoring domains. Here, an internet of things-based system scheme integrating the most recent technologies for designing a management platform for agricultural machines equipped with automatic navigation systems is proposed. Various agricultural machinery cyber-models and their corresponding sensor nodes were constructed in a pre-production phase. Three key enabling technologies&mdash;multi-optimization of agricultural machinery scheduling, development of physical architecture and software, and integration of the controller-area-network with a mobile network&mdash;were addressed to support the system scheme. A demonstrative prototype system was developed and a case study was used to validate the feasibility and effectiveness of the proposed approach

Developing an IoT-Enabled Cloud Management Platform for Agricultural Machinery Equipped with Automatic Navigation Systems

Smart farming uses advanced tools and technologies such as intelligent agricultural machines, high-precision sensors, navigation systems, and sophisticated computer systems to increase the economic benefits of agriculture and reduce the associated human effort. With the increasing demands of individualized farming operations, the internet of things is a crucial technique for acquiring, monitoring, processing, and managing the agricultural resource data of precision agriculture and ecological monitoring domains. Here, an internet of things-based system scheme integrating the most recent technologies for designing a management platform for agricultural machines equipped with automatic navigation systems is proposed. Various agricultural machinery cyber-models and their corresponding sensor nodes were constructed in a pre-production phase. Three key enabling technologies—multi-optimization of agricultural machinery scheduling, development of physical architecture and software, and integration of the controller-area-network with a mobile network—were addressed to support the system scheme. A demonstrative prototype system was developed and a case study was used to validate the feasibility and effectiveness of the proposed approach

Photochemical Dearomative Skeletal Modifications of Heteroaromatics

Dearomatization has emerged as a powerful manifold for rapid construction of 3D molecular architectures from simple, abundant, and planar (hetero)arenes. The field has evolved beyond the simple dearomatization driven by new synthetic technology development. With the renaissance of photocatalysis and expanding the activation mode, the last few years have witnessed impressive developments on innovative photochemical dearomatization methodologies, enabling skeletal modifications of the dearomatic structures. They offer truly efficient and useful tools for facile construction of highly complex structures in synthesis of nature products and drug discovery. In this review, we aim to provide a mechanistically insightful overview on these innovations based on the degree of skeletal alternation, categorized into dearomative functionalization and skeletal editing, and highlight their synthetic utilities

Highly Regio- and Stereoselective Synthesis of <i>Z</i> and <i>E</i> Enol Esters by an Amine-Catalyzed Conjugate Addition–Rearrangement Reaction of Ynals with Carboxylic Acids

The broad synthetic utility of labile enol esters demands efficient methods for the stereo- and regioselective synthesis of both <i>Z</i> and <i>E</i> isomers. The available synthetic methods dominated by metal catalysis cannot meet the challenge. We wish to report a metal-free organocatalytic divergent approach to both <i>E</i> and <i>Z</i> isomers of enol esters from the same reactant pools with the same catalytic system. A process involves an amine-catalyzed conjugate addition of carboxylic acids to ynals, which triggers a rearrangement leading to enol esters. The reaction proceeds highly regio- and stereoselectively. Simple manipulation of reaction temperatures enabled us to produce <i>Z</i> isomers at 0 °C (<i>Z:E</i> (15–20):1), whereas <i>E</i> isomers were produced at 30 °C (<i>E:Z</i> (15–20):1). Furthermore, the mild reaction conditions accommodate a broad array of densely functionalized carboxylic acids for the process, including complex biologically relevant structures and ynals. Therefore, synthetically valued, structurally diverse enol esters are efficiently synthesized. Preliminary mechanistic studies suggest an amine-promoted conjugate addition–rearrangement pathway to be responsible for the formation of the enol esters

Dynamic Kinetic Resolution of Biaryl Lactones via a Chiral Bifunctional Amine Thiourea-Catalyzed Highly Atropo-enantio­selective Transesterification

A solution to the unmet synthetic challenge of achieving highly atropo-enantio­selective transesterification of Bringmann’s lactones has been realized, employing a chiral bifunctional amine thiourea as promoter. The synergistic activation of the lactones and alcohols/phenols by the respective thiourea and amine groups is crucial for achieving the highly enantio­selective, high-yielding dynamic kinetic resolution process. This protocol gives highly optically pure, axially chiral biaryl compounds with a broad substrate scope under mild reaction conditions

Study on dietary intake, risk assessment, and molecular toxicity mechanism of benzo[α]pyrene in college students in China Bashu area

As an extremely strong polycyclic aromatic hydrocarbon carcinogen, benzo[α]pyrene (BaP) is often produced during food processing at high temperatures. Recently, food safety, as well as toxicity mechanism and risk assessment of BaP, has received extensive attention. We first constructed the database of BaP pollution concentration in Chinese daily food with over 104 data items; collected dietary intake data using online survey; then assessed dietary exposure risk; and finally revealed the possible toxicity mechanism through four comparative molecular dynamics (MD) simulations. The statistical results showed that the concentration of BaP in olive oil was the highest, followed by that in fried meat products. The margins of exposure and incremental lifetime cancer risk both indicated that the dietary exposure to BaP of the participants was generally safe, but there were still some people with certain carcinogenic risks. Specifically, the health risk of the core district population was higher than that of the noncore district in Bashu area, and the female postgraduate group was higher than the male group with bachelor degree or below. From MD trajectories, BaP binding does not affect the global motion of individual nucleic acid sequences, but local weak noncovalent interactions changed greatly; it also weakens molecular interactions of nucleic acid with Bacillus stearothermophilus DNA polymerase I large fragment (BF), and significantly changes the cavity structure of recognition interface. This work not only reveals the possible toxicity mechanism of BaP, but also provides theoretical guidance for the subsequent optimization of food safety standards and reference of rational diet

Synthesis of Tryptanthrins by Organocatalytic and Substrate Co-catalyzed Photochemical Condensation of Indoles and Anthranilic Acids with Visible Light and O₂

A metal-free catalytic approach to tryptanthrins has been achieved for the first time. The unique process is realized by an organocatalytic and indole and anthranilic acid substrate co-catalyzed photochemical oxidative condensation with visible light and O₂. The truly environmentally friendly reaction conditions enable various reactants to participate in the process to deliver structurally diverse tryptanthrins