Publications by authors named "Sai Jiang"

27 Publications

  • Page 1 of 1

A Smarter Pavlovian Dog with Optically Modulated Associative Learning in an Organic Ferroelectric Neuromem.

Research (Wash D C) 2021 20;2021:9820502. Epub 2021 Dec 20.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.

Associative learning is a critical learning principle uniting discrete ideas and percepts to improve individuals' adaptability. However, enabling high tunability of the association processes as in biological counterparts and thus integration of multiple signals from the environment, ideally in a single device, is challenging. Here, we fabricate an organic ferroelectric neuromem capable of monadically implementing optically modulated associative learning. This approach couples the photogating effect at the interface with ferroelectric polarization switching, enabling highly tunable optical modulation of charge carriers. Our device acts as a smarter Pavlovian dog exhibiting adjustable associative learning with the training cycles tuned from thirteen to two. In particular, we obtain a large output difference (>10), which is very similar to the all-or-nothing biological sensory/motor neuron spiking with decrementless conduction. As proof-of-concept demonstrations, photoferroelectric coupling-based applications in cryptography and logic gates are achieved in a single device, indicating compatibility with biological and digital data processing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.34133/2021/9820502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8715308PMC
December 2021

Retina-Inspired Self-Powered Artificial Optoelectronic Synapses with Selective Detection in Organic Asymmetric Heterojunctions.

Adv Sci (Weinh) 2022 Jan 12:e2103494. Epub 2022 Jan 12.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China.

The retina, the most crucial unit of the human visual perception system, combines sensing with wavelength selectivity and signal preprocessing. Incorporating energy conversion into these superior neurobiological features to generate core visual signals directly from incoming light under various conditions is essential for artificial optoelectronic synapses to emulate biological processing in the real retina. Herein, self-powered optoelectronic synapses that can selectively detect and preprocess the ultraviolet (UV) light are presented, which benefit from high-quality organic asymmetric heterojunctions with ultrathin molecular semiconducting crystalline films, intrinsic heterogeneous interfaces, and typical photovoltaic properties. These devices exhibit diverse synaptic behaviors, such as excitatory postsynaptic current, paired-pulse facilitation, and high-pass filtering characteristics, which successfully reproduce the unique connectivity among sensory neurons. These zero-power optical-sensing synaptic operations further facilitate a demonstration of image sharpening. Additionally, the charge transfer at the heterojunction interface can be modulated by tuning the gate voltage to achieve multispectral sensing ranging from the UV to near-infrared region. Therefore, this work sheds new light on more advanced retinomorphic visual systems in the post-Moore era.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/advs.202103494DOI Listing
January 2022

Cyclocarya paliurus (Batalin) Iljinskaja: Botany, Ethnopharmacology, phytochemistry and pharmacology.

J Ethnopharmacol 2022 Mar 11;285:114912. Epub 2021 Dec 11.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Materia Medica Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China. Electronic address:

Ethnopharmacological Relevance: Cyclocarya paliurus (Batalin) Iljinskaja (C. paliurus) also known as Sweet tea tree, Money tree, Money willow, green money plum, mountain willow and shanhua tree, is a native rare monocotyledonous plant in Southern China. It possesses numerous traditional benefits, including clearing heat, detoxification, producing saliva, slake thirst, anti-inflammatory, insecticidal, dispelling wind and relieving itching. It is also effective in preventing and treating diabetes, hypertension, hyperlipidemia, dizziness and swelling and pain, as well as reducing cholesterol, and modulating the functions of the immune system. The stem, leaves and bark of this plant are all medicinal parts, but the leaves have the highest research value.

Aim Of The Study: This article summarized the plant's botanical description, distribution, ethnopharmacology, phytochemical profiles and pharmacological for the first time, to provide possible directions for future development and research in brief.

Material And Methods: The literature for this current manuscript was obtained from reports published from 1992 to May 2021 in diverse databases such as the China Knowledge Resource Integrated databases (CNKI), SciFinder, Google Scholar, Baidu Scholar, Elsevier and Pub-Med. The domestic and foreign references published about C. paliurus over recent years were collected, analyzed and summarized.

Results: The botanical characteristics of the fruits of C. paliurus are unique in having a central nutlet surrounded by a circular wing to distinguish the living genera of Juglandaceae. In traditional medicine, C. paliurus leaves are used by the local people of Southern China to make tea to prevent diabetes. More than 210 compounds have been isolated from C. paliurus. Among them, the characteristic 3,4-seco-dammaranes accounted for the most. Other compounds include dammarane tetracyclic triterpenoids, various pentacyclic triterpenoids, flavonoids, isosclerones, phenolic derivatives and polysaccharides. The plant extracts and compounds have been reported to exert various pharmacological activities, such as anti-hyperglycemic, anti-hyperlipidemic, anti-cancer, cytotoxic, anti-oxidative, anti-inflammatory, hepatoprotective, and anti-microbial activities.

Conclusions: Comprehensive literature analysis shows that C. paliurus extract and its compounds have a variety of biological activities for the treatment of various diseases. The current modern pharmacology research is mostly related to the records of ethnic pharmacology, mainly in vitro research, relatively few in vivo research. Therefore, future studies should focus on this aspect. In addition, we also would like to recommend further research should concentrate on toxicity studies and quality control of C. paliurus to fill the study gap, as well as to provide theoretical support for the further development of the potential functions and clinical applications of the plant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jep.2021.114912DOI Listing
March 2022

Sesquiterpenes from Kadsura coccinea attenuate rheumatoid arthritis-related inflammation by inhibiting the NF-κB and JAK2/STAT3 signal pathways.

Phytochemistry 2022 Feb 24;194:113018. Epub 2021 Nov 24.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Materia Medica Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan, 410208, China. Electronic address:

The roots of Kadsura coccinea is commonly used in Tujia ethnomedicine, named "heilaohu", having the effect of treating rheumatic arthritis (RA). Chemical investigation on the ethanol extract of heilaohu led to the isolation of one undescribed cuparane sesquiterpenoid, heilaohusesquiterpenoid A, one undescribed carotane sesquiterpenoids, heilaohusesquiterpenoid B, and eighteen sesquiterpene derivatives. Their structures were subsequently determined based on their 1D and 2D-NMR, HR-ESI-MS, and ECD spectroscopic data. Gaultheriadiolide was the most cytotoxic compound against the proliferation of rheumatoid arthritis-fibroblastoid synovial (RA-FLS) cells with an IC value of 9.37 μM. In the same line, nine compounds exhibited significant inhibition effects against TNF-α and IL-6 release in the LPS-induced RAW264.7 cells with IC values ranging between 1.03 and 10.99 μM. The potential molecular mechanisms of the active compounds against RA were established through pharmacological network analysis based on the initial screening results. Experimental validation showed that gaultheriadiolide suppressed inflammation by inhibiting the NF-kB and JAK2/STAT3 pathways. This study enriches the structural diversity of sesquiterpenes in K. coccinea and lays a foundation for further anti-RA and anti-inflammatory studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.phytochem.2021.113018DOI Listing
February 2022

The medicinal uses of the genus Bletilla in traditional Chinese medicine: A phytochemical and pharmacological review.

J Ethnopharmacol 2021 Nov 16;280:114263. Epub 2021 Jun 16.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Material Medical Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, 410208, PR China. Electronic address:

Ethnopharmacological Relevance: Different orchids are important in traditional medicine, and species belonging to the genus Bletilla are important. Bletilla species have been used for thousands of years in Traditional Chinese Medicine (TCM) for the treatment of several health disorders, such as gastrointestinal disorders, peptic ulcer, lung disorders, and traumatic bleeding etc. AIM OF THIS REVIEW: This review aims to provide a systematic overview and objective analysis of Bletilla species and to find the probable relationship between their traditional use, chemical constituents, and pharmacological activities, while assessing their therapeutic potential in treatment of different human diseases.

Materials And Methods: Relevant literatures on Bletilla species have been collected using the keywords "Bletilla", "phytochemistry", and "pharmacology" in scientific databases, such as "PubMed", "Scifinder", "The Plant List", "Elsevier", "China Knowledge Resource Integrated databases (CNKI)", "Google Scholar", "Baidu Scholar", and other literature sources, etc. RESULTS: This review indicates the isolation and identification of over 261 compounds from this genus, till December 2020. These chemical isolates belong to the stilbenes (bibenzyls and phenanthrenes), flavonoids, triterpenoids, steroids, simple phenolics, and glucosyloxybenzyl 2-isobutylmalates classes of compounds. These compounds have been reported to be characteristically distributed in Bletilla striata (Thunb.) Rchb. f. (BS), Bletilla ochracea Schltr. (BO), and Bletilla formosana (Hayata) Schltr. (BF). The crude extracts and pure compounds derived from the three Bletilla species have reportedly exhibited a wide spectrum of in vitro and in vivo pharmacological effects, such as hemostatic, anti-inflammatory, anti-tumor, and anti-microbial activities. As a Traditional Chinese Medicine (TCM), Bletilla species or preparations containing Bletilla species have been used for the treatment of epistaxis, gastrointestinal bleeding, cough and hemoptysis, gastric and duodenal ulcer, and traumatic injuries. Thus, Bletilla species have proven potential both in traditional uses and scientific studies.

Conclusions: Pharmacological studies have validated the use of Bletilla species in the traditional medicine, especially hemorrhagic diseases. Polysaccharides and stilbenes are the major bioactive chemical constituents of Bletilla genus according to the literatures. However, the mechanism of action of these molecules is yet to be studied. In addition, a detailed comparative analysis of the phytochemistry and biological activities of the three Bletilla species (BS, BO and BF) is highly recommended for understanding their ethnopharmacological uses and applications in clinics. Clinical toxicity tests on BS have been found to be negative, but it can't be used with Aconitum carmichaeli in traditional uses. Furthermore, not many reports are present in the literature regarding the conservation of Bletilla species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jep.2021.114263DOI Listing
November 2021

Chemistry and Pharmacological Activity of Sesquiterpenoids from the Genus.

Molecules 2021 May 19;26(10). Epub 2021 May 19.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Materia Medica Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China.

Plants from the genus are rich sources of chemical diversity and, in recent years, have been the focus of research on natural products chemistry. Sesquiterpenoids are one of the major classes of chemical constituents reported from this genus. To date, more than 135 sesquiterpenoids have been isolated and identified from the whole genus. These include 26 germacrane-type, 26 eudesmane-type, 64 guaianolide-type, 4 bisabolane-type, and 15 other-type sesquiterpenoids. Pharmacological studies have proven the biological potential of sesquiterpenoids isolated from species, reporting anti-inflammatory, antibacterial, antitumor, insecticidal, and antiviral activities for these interesting molecules. In this paper, we provide information on the chemistry and bioactivity of sesquiterpenoids obtained from the genus which could be used as the scientific basis for their future development and utilization.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules26103038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8161347PMC
May 2021

Hybrid-cell membrane-coated nanocomplex-loaded chikusetsusaponin IVa methyl ester for a combinational therapy against breast cancer assisted by Ce6.

Biomater Sci 2021 Apr 2;9(8):2991-3004. Epub 2021 Mar 2.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Materia Medica Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha 410208, China.

Breast cancer is the most common cancer in women and occurs mostly with poor outcomes. Our objective was to endow synthetic lethality to the phytoconstituent chikusetsusaponin IVa methyl ester (CSME, S), a special phytoconstituent from traditional Chinese medicine (TCM), Panax japonicus, with the photodynamic agent chlorin e6 (Ce6, C) and enhance the therapeutic efficacy against breast cancer using cell membrane-coated liposome nanoparticles (liposome, L). The delivery system based on liposomes was camouflaged by a hybrid cell membrane (RBC membrane and cancer cell membrane, M) and RGD (R) surface modifications to improve the solubility, targeting and treatment outcomes of CSME. Our results showed the successful development of nanocomplexes with extended half-life, increased immune evasion and targeted ability at the tumor site and good antitumor activity without side effects to normal tissue. The anti-tumor mechanism of nanocomplexes is related to cell proliferation regulation and apoptosis induction. Overall, this drug-delivery system provides a good alternative for breast cancer therapy using a natural active phytoconstituent.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/d0bm02211jDOI Listing
April 2021

A review of the phytochemistry and pharmacology of Kadsura heteroclita, an important plant in Tujia ethnomedicine.

J Ethnopharmacol 2021 Mar 7;268:113567. Epub 2020 Nov 7.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Material Medical Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, 410208, PR China. Electronic address:

Ethnopharmacological Relevance: Kadsura heteroclita (Roxb.) Craib (traditionally known as "Xue Tong") is an important member of the economically and medicinally important plant family Schisandraceae. "Xue Tong" is an imperative ingredient of the Tujia ethnomedicine, traditionally used for the treatment of rheumatoid arthritis (RA), hepatitis, and muscles and joint spasm. The plant is known to be a rich source of lignans and triterpenoids. These classes of natural products have been known to possess various pharmacological activities.

Aim Of Review: This review was motivated by the importance of K. heteroclita in traditional Chinese medicine (TCM). It aims to compile the available information on its botanical distribution and description, traditional uses, phytochemistry, pharmacological activities, toxicity, and quality control to provide a solid base for further research and development.

Materials And Methods: Relevant literature was collected by several scientific databases including PubMed, CNKI, Scifinder, The Plant List, Google Scholar, Baidu Scholar, Books (Tujia pharmaceutical records, Guangxi Chinese herbal medicine, Hunan pharmaceutical records and Field identification manual of Chinese herbal medicine) and other literature sources (Flora of China, Pharmacopoeia of the People's Republic of China) which helped in collecting maximum data about the studied species.

Results: Traditional uses of K. heteroclita have proven its medicinal importance, providing a rationale for scientific research. Phytochemical studies on the stem of K. heteroclita resulted in the identification of 187 chemical constituents, among which lignans and triterpenoids are the predominant groups. The isolates and crude extracts have been found to exhibit a wide spectrum of in vivo and in vitro pharmacological activities such as anti-RA, anti-inflammatory and analgesic, hepatoprotection, anti-HIV, anti-cancer and anti-HBV. Schisanlactone E (xuetongsu), a triterpenoid, is one of the major components of K. heteroclita exhibiting anti-cancer, neuroprotective and anti-neuroinflammation activities. Interestingly and luckily, this plant has been found to be safe and non-toxic within the therapeutic dose range.

Conclusion: Pharmacological investigations have validated the use of K. heteroclita in traditional Chinese medicine (TCM). Literature review has demonstrated that lignans and triterpenoids are possibly responsible for most of the biological activities exhibited by this plant. To conclude, this plant shows immense potential for the discovery of more potent bioactive secondary metabolites and therefore further phytochemical and biological studies on other parts of K. heteroclita need to be conducted and more compounds need to be tested regarding their biological activities to completely explore its value as a tremendously important medicinal plant species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jep.2020.113567DOI Listing
March 2021

The flower head of Chrysanthemum morifolium Ramat. (Juhua): A paradigm of flowers serving as Chinese dietary herbal medicine.

J Ethnopharmacol 2020 Oct 25;261:113043. Epub 2020 Jun 25.

TCM and Ethnomedicine Innovation & Development International Laboratory, Innovative Material Medical Research Institute, School of Pharmacy, Hunan University of Chinese Medicine, Changsha, 410208, China. Electronic address:

Ethnopharmacological Relevance: Dietary herbal medicines are widely used for the prevention and treatment of a variety of diseases due to their pharmacological activities in China. Juhua (the flower head of Chrysanthemum morifolium Ramat.), the most representative flower-derived one, which is mainly used for the treatment of respiratory and cardiovascular diseases, shows significant activities, such as antimicrobial, anti-inflammatory, and anticancer, and, neuroprotective, as well as effects on the cardiovascular system.

Aims Of This Review: This review aims to provide an overview of the crucial roles of flowers in Chinese dietary herbal medicine, and the pharmaceutical research progress of Juhua (the paradigm of dietary herbal medicine derived from the flower) including its applications in Traditional Chinese medicine and diet, cultivars, phytochemistry, quality control, pharmacology, and toxicity, along with chrysanthemum breeding and biotechnology.

Method: The information associated with Chinese dietary herbal medicine, flower-derived medicine, dietary flower, and pharmaceutical research of Juhua, was collected from government reports, classic books of Traditional Chinese medicine, the thesis of doctors of philosophy and maters, and database including Pubmed, Scifinder, Web of Science, Google Scholar, China National Knowledge Internet; and others.

Result: All flower-originated crude medicines recorded in Chinese pharmacopeia and their applications were summarized for the first time in this paper. The edible history and development of flowers in China, the theory of Chinese dietary herbal medicines, as well as flowers serving as dietary herbal medicines, were discussed. Moreover, applications in Traditional Chinese medicine and diet, cultivars, phytochemistry, quality control, pharmacology, and safety evaluation of Juhua, together with chrysanthemum breeding and biotechnology, were summarized in this paper.

Conclusion: The theory of dietary herbal medicines, which are an important part of the Traditional Chinese medicine system, has a history of thousands of years. Many herbal flowers, serving as dietary herbal medicines, contribute significantly to the prevention and treatment of a variety of diseases for Chinese people. To better benefit human health, more effective supervision practice for dietary herbal medicines is needed. Although various investigations on Juhua have been done, there is a lack of analytical methods for discrimination of cultivar flowers and identification of authenticity. Research on the major compounds with bioactivities, especially those related to its clinical application or healthcare function, as well as their possible mechanize, need be strengthened. More safety evaluation of Juhua should be carried out. The research limitations Juhua is facing exist in all dietary herbal medicine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jep.2020.113043DOI Listing
October 2020

Molecular Layer-Defined Transition of Carrier Distribution and Correlation with Transport in Organic Crystalline Semiconductors.

ACS Appl Mater Interfaces 2020 Jun 27;12(23):26267-26275. Epub 2020 May 27.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, Jiangsu 210093, P. R. China.

Despite the great efforts to unveil the charge carrier behavior at the semiconductor/dielectric interface of organic field-effect transistors, an examination of the interfacial carrier distribution and the correlation with the charge transport in molecular crystalline semiconductors remains fundamental for understanding the nature of the microscopic carrier motion. Hence, an effective approach to accurately tune the carrier distribution with molecular-layer precision is essential. Here, we find that the carrier accumulation is strictly modulated in highly ordered, few-layer molecular crystalline semiconducting films by tuning the polaronic coupling between the charge carriers and dielectric. The admittance method reveals that the carriers distribute only within a monolayer with stronger localization on a high-κ dielectric and extend to a second layer with better delocalization on a low-κ dielectric. Furthermore, a unique dimensional transition in the charge transport at the dielectric interface is evidenced under a transistor architecture by temperature-dependent measurements. The presented microscopic nature of charge carriers with layer-defined precision in molecular crystalline films should provide an unprecedented opportunity in organic electronics in terms of interface engineering, quantum transport, and device physics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.0c04873DOI Listing
June 2020

Achieving High-Performance Photothermal and Photodynamic Effects upon Combining D-A Structure and Nonplanar Conformation.

Small 2020 04 6;16(17):e2000909. Epub 2020 Apr 6.

College of Materials Science and Opto-Electronic Technology, Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.

Various organic nanoagents have been developed for photothermal therapy (PTT) and photodynamic therapy (PDT) under near-infrared (NIR) irradiation. Among them, small molecule-based nanoagents are very attractive due to their advantages of well-defined chemical structures, high purity, good reproducibility, and easy processability. However, only a few small molecule-based nanoagents have been developed for PDT under NIR irradiation. Moreover, the mechanism of PDT under NIR is still elusive. Herein, a semiconducting small molecule (BTA) with donor-acceptor-donor structure and twisted conformation is developed for PDT/PTT under NIR irradiation. A large π-conjugated electron-deficient unit is used as the core to couple with two electron-donating units, ensuring the strong absorption under 808 nm. Moreover, the donor-acceptor structures and twisted conformation can reduce the energy gap between the singlet and triplet states (∆E ) to afford effective intersystem crossing, beneficial for reactive oxygen species generation. The mechanism is probed by experimental and theoretical evidence. Moreover, the BTA nanoparticles exhibit excellent biocompatibility and PTT/PDT in vitro performance under NIR irradiation. This provides a strategy for designing highly efficient PDT/PTT molecular materials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/smll.202000909DOI Listing
April 2020

Role of Schottky Barrier and Access Resistance in Organic Field-Effect Transistors.

J Phys Chem Lett 2020 Feb 7;11(4):1466-1472. Epub 2020 Feb 7.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China.

Despite the increasing understanding of charge transport in organic field-effect transistors (OFETs), charge injection from source/drain electrodes into organic semiconductors remains crucial for improving device performance and lowering power consumption. The analysis of contact resistance is generally carried out without clearly distinguishing the Schottky barrier and access resistance. Here we show that the access resistance through the organic semiconductor bulk can significantly influence the Schottky barrier evaluation and affect the charge-transport exploration. Indeed, access resistance plays a leading role in the contact resistance, whereas the Schottky barrier (expressed as the interface resistance) determines the charge injection at the metal/semiconductor interface. The Schottky barrier evaluation strongly depends on the access resistance and bias voltage. After eliminating the access resistance effect, the intrinsic Schottky barrier appears to be very coincident and weakly dependent on the work function of the contact metal. This work provides clues to understanding the Schottky barrier and charge injection in OFETs to optimize OFETs for high-performance and advanced applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpclett.9b03339DOI Listing
February 2020

Antibacterial stilbenes from the tubers of Bletilla striata.

Fitoterapia 2019 Oct 30;138:104350. Epub 2019 Aug 30.

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China; The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences, Guizhou Provincial Engineering Research Center for Natural Drugs, Guiyang 550014, PR China. Electronic address:

Three new bibenzyl derivatives (bletstrins A-C, 1-3), including two bibenzyls that have hydroxyl-substituted chiral centers on the aliphatic bibenzyl bridge, along with eighteen known stilbenoids (4-21) were isolated from the tubers of Bletilla striata. The structures of new compounds were elucidated by the use of 1D/2D NMR spectroscopic data. The absolute configurations of bletitrins A and B were determined by optical rotation value. Compounds 13-16 were isolated from the Orchidaceae for the first time. Most of the isolated compounds were evaluated for their antibacterial activities against three gram-positive bacterial strains and one gram-negative bacterial strain. Compounds 4, 10, 12, 14, 15, 16 and 18 showed potent inhibitory activities, with MICs of (6-52 μg/mL) against S. aureus ATCC 6538.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fitote.2019.104350DOI Listing
October 2019

pJ-Level Energy-Consuming, Low-Voltage Ferroelectric Organic Field-Effect Transistor Memories.

J Phys Chem Lett 2019 May 26;10(10):2335-2340. Epub 2019 Apr 26.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing , Jiangsu 210093 , People's Republic of China.

Ferroelectric organic field-effect transistors (Fe-OFETs) have attracted considerable attention because of their promising potential for memory applications, while a critical issue is the large energy consumption mainly caused by a high operating voltage and slow data switching. Here, we employ ultrathin ferroelectric polymer and semiconducting molecular crystals to create low-voltage Fe-OFET memories. Devices require only pJ-level energy consumption. The writing and erasing processes require ∼1.2 and 1.6 pJ/bit, respectively, and the reading energy is ∼1.9 pJ/bit (on state) and ∼0.2 fJ/bit (off state). Thus, our memories consume only <0.1% of the energy required for devices using bulk functional layers. Besides, our devices also exhibit low contact resistance and steep subthreshold swing. Therefore, we provide a strategy that opens up a path for Fe-OFETs toward emerging applications, such as wearable electronics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpclett.9b00864DOI Listing
May 2019

Antibacterial bibenzyl derivatives from the tubers of Bletilla striata.

Phytochemistry 2019 Jun 3;162:216-223. Epub 2019 Apr 3.

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, PR China. Electronic address:

Ten previously undescribed bibenzyl derivatives (bletistrins A-J), including 5 that have hydroxyl-substituted chiral centres on the aliphatic bibenzyl bridge, along with twelve known bibenzyl derivatives, were isolated from the rhizomes of Bletilla striata. The structures of bletistrins A-J were primarily elucidated on the basis of their 1D and 2D NMR spectroscopic data. The absolute configurations of bletistrins A, D, F, H and I were determined by electronic circular dichroism (ECD) spectroscopic analysis and optical rotation value. Most of the isolated compounds were evaluated for their antibacterial activities against 3 g-positive bacterial strains and 1 g-negative bacterial strain. Bletistrins F, G, and J, bulbocol, shanciguol and shancigusin B showed inhibitory activities, with MICs of (3-28 μg/mL) against S. aureus ATCC 6538.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.phytochem.2019.03.022DOI Listing
June 2019

Millimeter-Sized Two-Dimensional Molecular Crystalline Semiconductors with Precisely Defined Molecular Layers via Interfacial-Interaction-Modulated Self-Assembly.

J Phys Chem Lett 2018 Dec 13;9(23):6755-6760. Epub 2018 Nov 13.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing , Jiangsu 210093 , P. R. China.

The newly emerging field in organic electronics is to control the molecule-substrate interface properties at a two-dimensional (2D) limit via interfacial interactions, which paves the way for driving the molecular assembly for highly ordered 2D molecular crystalline films with precise molecular layers and large-area uniformity. Here, by exploiting molecule-substrate van der Waals (vdW) interactions, we demonstrate thermally induced self-assembly of 2D organic crystalline films exhibiting well-defined molecular layer number over a millimeter-sized area. The organic field-effect transistors (OFETs) with bilayer films show excellent electrical performance with a maximum mobility of 12.8 cm V s. Moreover, we find that the monolayer films can act as interfacial molecular templates to construct heterojunctions with well-balanced ambipolar transport behaviors. The capability of thermally induced self-assembly of 2D molecular crystalline films with controllable molecular layers and scale-up coverage opens up a way for realizing complicated electronic applications, such as lateral heterojunctions and superlattices.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpclett.8b03108DOI Listing
December 2018

Novel sesquiterpenoids isolated from Chimonanthus praecox and their antibacterial activities.

Chin J Nat Med 2018 Aug;16(8):621-627

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China; The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences, Guiyang 550014, China. Electronic address:

In the present study, four new sesquiterpenoids, chimonols A-D (compounds 1-4), together with four known compounds (5-8) were isolated from the EtOAc extract of Chimonanthus praecox Link. The structures of these new compounds were elucidated on the basis of spectroscopic techniques (UV, IR, MS, and 1D and 2D NMR), and their absolute configurations were established by comparing experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1-8 were evaluated for antimicrobial activities and the minimum inhibitory concentrations (MICs) were determined by the broth microdilution method in 96-well culture plates. Compounds 1, 2, and 7 exhibited weak antibacterial effects for S. aureus (ATCC 6538), E. coli (ATCC 11775), and P. aeruginosa (ATCC 10145) with MIC values being 158-249 µg·mL. Compounds 3-7 showed activities against C. glabrata (ATCC 2001) and S. aureus (ATCC 43300) with MIC values being 128-197 µg·mL. Compounds 1-4 showed activity against S. aureus (ATCC 25923) with MIC values being 162-254 µg·mL. The present study provided a basis for future evaluation of these compounds as antibacterial agents.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/S1875-5364(18)30100-6DOI Listing
August 2018

Interfacial Flat-Lying Molecular Monolayers for Performance Enhancement in Organic Field-Effect Transistors.

ACS Appl Mater Interfaces 2018 Jul 19;10(26):22513-22519. Epub 2018 Jun 19.

National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , P. R. China.

Organic field-effect transistors (OFETs) are the most fundamental device units in organic electronics. Interface engineering at the semiconductor/dielectric interface is an effective approach for improving device performance, particularly for enhancing charge transport in conducting channels. Here, we report flat-lying molecular monolayers that exhibit good uniformity and high crystallinity at the semiconductor/dielectric interface, deposited through slow thermal evaporation. Transistor devices achieve high carrier mobility up to 2.80 cm V s, which represents a remarkably improvement in device performance compared with devices that are completely based on fast-evaporated films. Interfacial flat-lying monolayers benefit charge transport by suppressing the polarization of dipoles and narrowing the broadening of trap density of states. Our work provides a promising strategy for enhancing the performance of OFETs by using interfacial flat-lying molecular monolayers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.8b07095DOI Listing
July 2018

A Sequential Multiplicative Extended Kalman Filter for Attitude Estimation Using Vector Observations.

Sensors (Basel) 2018 May 3;18(5). Epub 2018 May 3.

Department of Navigation Engineering, Naval University of Engineering, Wuhan 430000, China.

In this paper, a sequential multiplicative extended Kalman filter (SMEKF) is proposed for attitude estimation using vector observations. In the proposed SMEKF, each of the vector observations is processed sequentially to update the attitude, which can make the measurement model linearization more accurate for the next vector observation. This is the main difference to Murrell’s variation of the MEKF, which does not update the attitude estimate during the sequential procedure. Meanwhile, the covariance is updated after all the vector observations have been processed, which is used to account for the special characteristics of the reset operation necessary for the attitude update. This is the main difference to the traditional sequential EKF, which updates the state covariance at each step of the sequential procedure. The numerical simulation study demonstrates that the proposed SMEKF has more consistent and accurate performance in a wide range of initial estimate errors compared to the MEKF and its traditional sequential forms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/s18051414DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5982416PMC
May 2018

Spin-Coated Crystalline Molecular Monolayers for Performance Enhancement in Organic Field-Effect Transistors.

J Phys Chem Lett 2018 Mar 5;9(6):1318-1323. Epub 2018 Mar 5.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , PR China.

In organic field-effect transistors, the first few molecular layers at the semiconductor/dielectric interface are regarded as the active channel for charge transport; thus, great efforts have been devoted to the modification and optimization of molecular packing at such interfaces. Here, we report organic monolayers with large-area uniformity and high crystallinity deposited by an antisolvent-assisted spin-coating method acting as the templating layers between the dielectric and thermally evaporated semiconducting layers. The predeposited crystalline monolayers significantly enhance the film crystallinity of upper layers and the overall performance of transistors using these hybrid-deposited semiconducting films, showing a high carrier mobility up to 11.3 cm V s. Additionally, patterned transistor arrays composed of the templating monolayers are fabricated, yielding an average mobility of 7.7 cm V s. This work demonstrates a promising method for fabricating low-cost, high-performance, and large-area organic electronics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jpclett.8b00352DOI Listing
March 2018

Unveiling the piezoelectric nature of polar α-phase P(VDF-TrFE) at quasi-two-dimensional limit.

Sci Rep 2018 01 11;8(1):532. Epub 2018 Jan 11.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, P. R. China.

Piezoelectric response of P(VDF-TrFE), which is modulated by the dipole density due to the polarization switching on applying an electric field, allows it act as the fundamental components for electromechanical systems. As proposed since the 1970s, its polar α-phase is supposed to yield an enhanced piezoelectric activity. However, its experimental verification has never been reported, hampered by a substantial challenge for the achievement of a smooth, neat α-phase film. Here, we prepare ultrathin crystalline α-phase P(VDF-TrFE) films on the AlO/Al-coated SiO/Si substrates via a solution-based approach at room temperature. Thus, we unveil the piezoelectric nature of the polar α-phase P(VDF-TrFE) at a quasi-two-dimensional limit. The obtained values of the relative morphological deformation, the local effective piezoelectric coefficient, and the electric field-induced strain reach up to 37 pm, -46.4 pm V, and 4.1%, respectively. Such a robust piezoelectric response is even higher than that of the β-phase. Besides, the evolution of piezoelectricity, which is related to the piezoelectric properties of two polarization states, is also studied. Our work can enable the exploration of the prospective applications of polar α-phase P(VDF-TrFE) films.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-18845-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5765141PMC
January 2018

Growth of Black Phosphorus Nanobelts and Microbelts.

Small 2018 01 24;14(1). Epub 2017 Nov 24.

School of Electronic Science and Engineering, Nanjing University, Nanjing, 210046, China.

Black phosphorus nanobelts are fabricated with a one-step solid-liquid-solid reaction method under ambient pressure, where red phosphorus is used as the precursor instead of white phosphorus. The thickness of the as-fabricated nanobelts ranges from micrometers to tens of nanometers as studied by scanning electron microscopy. Energy dispersive X-ray spectroscopy and X-ray diffraction indicate that the nanobelts have the composition and the structure of black phosphorus, transmission electron microscopy reveals a typical layered structure stacked along the b-axis, and scanning transmission electron microscopy with energy dispersive X-ray spectroscopy analysis demonstrates the doping of bismuth into the black phosphorus structure. The nanobelt can be directly measured in scanning tunneling microscopy in ambient conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/smll.201702501DOI Listing
January 2018

Novel Flavones from the Root of Phytolacca acinosa Roxb.

Chem Biodivers 2017 Dec 15;14(12). Epub 2017 Dec 15.

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, 3491 Baijin Road, Guiyang, 550014, P. R. China.

Two new flavones, 6,7-methylenedioxy-4-hydroxypeltogynan-7'-one (1), cochliophilin B (2), as well as two known ones, cochliophilin A (3) and 6-methoxy-7-hydroxy flavone (4), were isolated from the ethanol extract of the root of Phytolacca acinosa Roxb. Compound 1 is a flavanol framework with one δ-lactone unit, which is rather rare in nature. The structures of the new compounds were determined on the basis of extensive spectroscopic (IR, MS, 1D- and 2D-NMR) analyses, the absolute configuration of 1 was established by comparing experimental and calculated electronic circular dichroism spectra. The structures of known compounds were fixed by comparison with literatures data. Compounds 2 and 4 showed modest inhibitory activities against BEL-7402 cell line, with IC values of 28.22 and 39.16 μmol/L, respectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cbdv.201700361DOI Listing
December 2017

Low-voltage, High-performance Organic Field-Effect Transistors Based on 2D Crystalline Molecular Semiconductors.

Sci Rep 2017 08 10;7(1):7830. Epub 2017 Aug 10.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China.

Two dimensional (2D) molecular crystals have attracted considerable attention because of their promising potential in electrical device applications, such as high-performance field-effect transistors (FETs). However, such devices demand high voltages, thereby considerably increasing power consumption. This study demonstrates the fabrication of organic FETs based on 2D crystalline films as semiconducting channels. The application of high-κ oxide dielectrics allows the transistors run under a low operating voltage (-4 V). The devices exhibited a high electrical performance with a carrier mobility up to 9.8 cm V s. Further results show that the AlO layer is beneficial to the charge transport at the conducting channels of FETs. Thus, the device strategy presented in this work is favorable for 2D molecular crystal-based transistors that can operate under low voltages.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-08280-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5552882PMC
August 2017

Speed up Ferroelectric Organic Transistor Memories by Using Two-Dimensional Molecular Crystalline Semiconductors.

ACS Appl Mater Interfaces 2017 May 17;9(21):18127-18133. Epub 2017 May 17.

National Laboratory of Solid-State Microstructures, School of Electronic Science and Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China.

Ferroelectric organic field-effect transistors (Fe-OFETs) have attracted intensive attention because of their promising potential in nonvolatile memory devices. The quick switching between binary states is a significant fundamental feature in evaluating Fe-OFET memories. Here, we employ 2D molecular crystals via a solution-based process as the conducting channels in transistor devices, in which ferroelectric polymer acts as the gate dielectric. A high carrier mobility of up to 5.6 cm V s and a high on/off ratio of 10 are obtained. In addition, the efficient charge injection by virtue of the ultrathin 2D molecular crystals is beneficial in achieving rapid operations in the Fe-OFETs; devices exhibit short switching time of ∼2.9 and ∼3.0 ms from the on- to the off-state and from the off- to the on-state, respectively. Consequently, the presented strategy is capable of speeding up Fe-OFET memory devices by using solution-processed 2D molecular crystals.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.7b03785DOI Listing
May 2017

[Treatment of anterior dislocation of shoulder joint by bone setting manipulation at zero position].

Zhongguo Gu Shang 2008 Jun;21(6):469

Department of Orthopaedics, the People Hospital of Yuhuan, Yuhuan 317600, Zhejiang, China.

View Article and Find Full Text PDF

Download full-text PDF

Source
June 2008
-->