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Yang ST, Yang TH, Liang BW, Lo HC, Chang WH, Lin PY, Su CY, Lan YW. Submicron Memtransistors Made from Monocrystalline Molybdenum Disulfide. ACS Nano 2024; 18:6936-6945. [PMID: 38271620 DOI: 10.1021/acsnano.3c09030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Multiterminal memtransistors made from two-dimensional (2D) materials have garnered increasing attention in the pursuit of low-power heterosynaptic neuromorphic circuits. However, existing 2D memtransistors tend to necessitate high set voltages (>1 V) or feature defective channels, posing concerns regarding material integrity and intrinsic properties. Herein, we present a monocrystalline monolayer MoS2 memtransistor designed for operation within submicron regimes. Under reverse drain bias sweeps, our experiments reveal memristive behavior within the device, further controllable through modulation of the gate terminal. This controllability facilitates the consistent manifestation of multistate memory effects. Notably, the memtransistor behavior becomes more significant as the channel length diminishes, particularly with channel lengths below 1.6 μm, showcasing an increase in the switching ratio alongside a decrease in the set voltage with the decreasing channel length. Our optimized memtransistor demonstrates the ability to exhibit individual resistance states spanning 5 orders of magnitude, with switching drain voltages of approximately 0.05 V. To elucidate these findings, we investigate hot carrier effects and their interplay with oxide traps within the HfO2 dielectric. This work highlights the importance of memtransisor behavior in highly scaled 2D transistors, particularly those featuring low contact resistances. This understanding holds the potential to tailor memory characteristics essential for the development of energy-efficient neuromorphic devices.
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Affiliation(s)
- Shu-Ting Yang
- Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 116, Taiwan
| | - Tilo H Yang
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Bor-Wei Liang
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, 300091 Hsinchu, Taiwan
| | - Han-Chieh Lo
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan
| | - Wen-Hao Chang
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan
| | - Po-Yen Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan
| | - Ching-Yuan Su
- Graduate Institute of Energy Engineering, National Central University, Taoyuan 320317, Taiwan
| | - Yann-Wen Lan
- Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan
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Liang BW, Chang WH, Huang CS, Huang YJ, Chen JH, Li KS, Simbulan KB, Kumar H, Su CY, Kuan CH, Lan YW. Self-powered broadband photodetection enabled by facile CVD-grown MoS 2/GaN heterostructures. Nanoscale 2023; 15:18233-18240. [PMID: 37943087 DOI: 10.1039/d3nr03877g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Achieving self-powered photodetection without biasing is a notable challenge for photodetectors. In this work, we demonstrate the successful fabrication of large-scale van der Waals epitaxial molybdenum disulfide (MoS2) on a p-GaN/sapphire substrate using a straightforward chemical vapor deposition (CVD) technique. Our research primarily centers on the characterization of these photodetectors produced through this method. The MoS2/GaN heterojunction photodetector showcases a broad and extensive photoresponse spanning from ultraviolet A (UVA) to near-infrared (NIR). When illuminated by a 532 nm laser, its self-powered photoresponse is characterized by a rise time (τr) of ∼18.5 ms and a decay time (τd) of ∼123.2 ms. The photodetector achieves a responsivity (R) of ∼0.13 A W-1 and a specific detectivity (D*) of ∼3.8 × 1010 Jones at zero bias. Additionally, while utilizing a 404 nm laser, the photodetector reaches a maximum R and D* of ∼1.7 × 104 A/W and ∼1.6 × 1013 Jones, respectively, at Vb = 5 V. The operational mechanism of the device can be explained by the diode characteristics involving a tunneling current in the presence of reverse bias. The exceptional performance of these photodetectors can be attributed to the pristine interface between the CVD-grown MoS2 and GaN, providing an impeccably clean tunneling surface. Additionally, our investigation has unveiled that MoS2/GaN heterostructure photodetectors, featuring MoS2 coverage percentages spanning from 20% to 50%, exhibit improved responsivity capabilities at an external bias voltage. As a result, this facile CVD growth technique for MoS2 photodetectors holds significant potential for large-scale production in the manufacturing industry.
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Affiliation(s)
- Bor-Wei Liang
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Wen-Hao Chang
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan.
| | - Chun-Sheng Huang
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - You-Jia Huang
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan.
| | - Jyun-Hong Chen
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Kai-Shin Li
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Kristan Bryan Simbulan
- Research Center for the Natural and Applied Sciences, University of Santo Tomas, Manila 1008, Philippines
| | - Harshvardhan Kumar
- Department of Electronics and Communication Engineering, The LNM Institute of Information Technology, Rupa ki Nangal, Post-Sumel, Via, Jamdoli, Jaipur, Rajasthan 302031, India
| | - Ching-Yuan Su
- Graduate Institute of Energy Engineering, National Central University, Taoyuan, 320317, Taiwan
| | - Chieh-Hsiung Kuan
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yann-Wen Lan
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan.
- Advanced Materials and Green Energy Research Center, National Taiwan Normal University, Taipei 11677, Taiwan
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Liang BW, Li MF, Lin HY, Li KS, Chen JH, Shieh JM, Wu CT, Simbulan KB, Su CY, Kuan CH, Lan YW. Dual-mode frequency multiplier in graphene-base hot electron transistor. Nanoscale 2023; 15:2586-2594. [PMID: 36691938 DOI: 10.1039/d2nr06285b] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Since quantum computers have been gradually introduced in countries around the world, the development of the many related quantum components that can operate independently of temperature has become more important for enabling mature products with low power dissipation and high efficiency. As an alternative to studying cryo-CMOSs (complementary metal-oxide-semiconductors) to achieve this goal, quantum tunneling devices based on 2D materials can be examined instead. In this work, a vertical graphene-based quantum tunneling transistor has been used as a frequency modulator. The transistor can operate via different quantum tunneling mechanisms and generates, by applying the appropriate bias, voltage-resistance curves characteristic of variable nonlinear resistance for both base and emitter voltages. We experimentally demonstrate frequency modulation from input signals over the range of 100 kHz to 10 MHz, enabling a tunable frequency doubler or tripler in just a single transistor. This frequency multiplication with a tunneling mechanism makes the graphene-based tunneling device a promising option for frequency electronics in the emerging field of quantum technologies.
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Affiliation(s)
- Bor-Wei Liang
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Min-Fang Li
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Hung-Yu Lin
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Kai-Shin Li
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Jyun-Hong Chen
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Jia-Min Shieh
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Chien-Ting Wu
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Kristan Bryan Simbulan
- Department of Mathematics and Physics, University of Santo Tomas, Manila 1008, Philippines
| | - Ching-Yuan Su
- Graduate Institute of Energy Engineering, National Central University, No. 300, Jhongda Rd., Jhongli, Taoyuan, 320317, Taiwan
| | - Chieh-Hsiung Kuan
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yann-Wen Lan
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan
- Advanced Materials and Green Energy Research Center, National Taiwan Normal University, Taipei 11677, Taiwan.
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Zhan YW, Feng AP, Liang BW, Gao YX, Lu Y, Wang ZY, Shu YL, Zou HC. [Employment, turnover intention and the associated factors among public health graduates in China]. Zhonghua Yu Fang Yi Xue Za Zhi 2021; 55:910-915. [PMID: 34304431 DOI: 10.3760/cma.j.cn112150-20210104-00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To understand the employment situation of graduates of public health-related majors and explore the associated factors of turnover intention among public health practitioners in China. Methods: In April 2020, the convenient sampling method was used to recruit public health related graduates from 98 universities with public health-related majors from 31 provinces in China (excluding Hong Kong, Macao and Taiwan) and from Chinese Center for Disease Control and Prevention (only including working or unemployed status, no requirement for graduation years). A total of 1 322 questionnaires were collected, of which 1 165 (88.1%) were valid. Through the network questionnaire survey, the information of public health graduates' work situation, job satisfaction and turnover intention were collected. Multivariate logistic regression model was used to analyze the associated factors of turnover intention, and structural equation model was constructed to explore the correlation between turnover intention and job satisfaction. Results: The age of 1 165 graduates was (28.1±4.8) years. Among them, 719 (61.7%) were female and 856 (73.5%) graduates were engaged in public health-related work after graduation. The results of multivariate logistic regression analysis showed that compared with those over 30 years old, graduates under 30 years old had higher turnover intention (OR=2.531, 95%CI: 1.549-4.155). Compared with those with junior or no title, graduates with senior title had higher turnover intention (OR=2.310, 95%CI: 1.047-5.162). The results of structural equation model analysis showed that the four factors of job satisfaction, 'salary and welfare', 'promotion development', 'work itself', and 'internal and external environment', were negatively correlated with turnover intention. The internal and external environment had the greatest impact on turnover intention (total effect =-0.539). Conclusion: Most graduates of public health-related majors are engaged in public health-related work in China. Age, professional title and job satisfaction are the associated factors of turnover intention.
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Affiliation(s)
- Y W Zhan
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
| | - A P Feng
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
| | - B W Liang
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
| | - Y X Gao
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
| | - Y Lu
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Z Y Wang
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Y L Shu
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
| | - H C Zou
- School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen 510006, China
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Liang BW, Chang WH, Lin HY, Chen PC, Zhang YT, Simbulan KB, Li KS, Chen JH, Kuan CH, Lan YW. High-Frequency Graphene Base Hot-Electron Transistor. ACS Nano 2021; 15:6756-6764. [PMID: 33734665 DOI: 10.1021/acsnano.0c10208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The integration of graphene and other two-dimensional (2D) materials with existing silicon semiconductor technology is highly desirable. This is due to the diverse advantages and potential applications brought about by the consequent miniaturization of the resulting electronic devices. Nevertheless, such devices that can operate at very high frequencies for high-speed applications are eminently preferred. In this work, we demonstrate a vertical graphene base hot-electron transistor that performs in the radio frequency regime. Our device exhibits a relatively high current density (∼200 A/cm2), high common base current gain (α* ∼ 99.2%), and moderate common emitter current gain (β* ∼ 2.7) at room temperature with an intrinsic current gain cutoff frequency of around 65 GHz. Furthermore, cutoff frequency can be tuned from 54 to 65 GHz by varying the collector-base bias. We anticipate that this proposed transistor design, built by the integrated 2D material and silicon semiconductor technology, can be a potential candidate to realize extra fast radio frequency tunneling hot-carrier electronics.
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Affiliation(s)
- Bor-Wei Liang
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Wen-Hao Chang
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Hung-Yu Lin
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Po-Chun Chen
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Yi-Tang Zhang
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | | | - Kai-Shin Li
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Jyun-Hong Chen
- Taiwan Semiconductor Research Institute, National Applied Research Laboratories, Hsinchu 30078, Taiwan
| | - Chieh-Hsiung Kuan
- Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yann-Wen Lan
- Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan
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Liang BW, Zhan YW, Feng AP, Gao YX, Li PY, Shu YL, Zou HC. [A survey on the willingness of college students majoring in public health to work in their majors]. Zhonghua Liu Xing Bing Xue Za Zhi 2021; 42:562-568. [PMID: 34814430 DOI: 10.3760/cma.j.cn112338-20200629-00898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Objective: To understand the basic qualities, practitioners will and related influences, of undergraduate, master, and doctoral students majoring in public health (hereinafter referred to as public health students), and explore the influencing factors of practitioners will. Methods: Through the online questionnaire survey, we collected information on the basic qualities of the public health students, their practitioners will and related influencing factors, and their opinions on the current state of public health in China. χ2 test and multi-factor logistic regression were used to analyze the influencing factors of public health students' willingness to engage in public health related work, and word frequency analysis was used to conduct a descriptive analysis of public health students' views on public health in China. Results: A total of 2 081 pieces of valid information were collected, of which 86.54% (1 801/2 081) of the students in the school chose to engage in public health related work in the future. For public health students, the higher the target after-tax monthly income (OR=0.345, 95%CI: 0.158-0.751), the lower the willingness to engage in public health related work in the future; Very satisfied with school employment guidance work (OR=4.072, 95%CI: 1.234-13.436) compared with very dissatisfied, the willingness to engage in public health related work in the future is higher. Conclusion: The willingness of students in public health related majors to engage in public health related majors in China is mainly affected by three factors: payment levels, employment guidance and professional post recognition. It is recommended to appropriately raise the salaries of public health related positions. Strengthening school employment guidance training and professional identity training is conducive to enhancing the willingness of public health students to engage in relevant work in their profession.
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Affiliation(s)
- B W Liang
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - Y W Zhan
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - A P Feng
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - Y X Gao
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - P Y Li
- School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - Y L Shu
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - H C Zou
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
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Feng AP, Zhan YW, Liang BW, Gao YX, Yuan TW, Shu YL, Zou HC. [Status quo regarding the recruit requirements of public health-related employers and training scheme for undergraduates majored in preventive medicine in colleges and universities]. Zhonghua Liu Xing Bing Xue Za Zhi 2021; 42:555-561. [PMID: 34814429 DOI: 10.3760/cma.j.cn112338-20200629-00896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Objective: To investigate public health-related professions' recruit requirements and understand the training scheme for preventive medicine-majored undergraduates in colleges and universities in China. Methods: An online questionnaire was adopted to collect data on the recruit requirements of public health-related professions. Information on the core courses, internship, and practical training for preventive medicine-majored undergraduates was collected through universities' official websites. Results: The employers had a high requirement for education and specific majors. Also, administration professions attached importance to comprehensive quality, while professional positions to professional skills. 47.2% (67/142) employers made Talent Introduction Programs for the next three years. 20.0% (3/15) universities offered all the core courses required by national standards. For internship and practical training, both clinical practice and professional practice's median durations were 16 and 11 weeks, respectively. Conclusion: Employers showed significant demand for public health graduates and having a high requirement for personal ability and comprehensive quality. The universities should improve the setting of core courses and strengthen students' practical ability and overall quality.
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Affiliation(s)
- A P Feng
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - Y W Zhan
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - B W Liang
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - Y X Gao
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - T W Yuan
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - Y L Shu
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
| | - H C Zou
- School of Public Health, Sun Yat-sen University (Shenzhen), Shenzhen 518107, China
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Liang BW, Huang CC, Chao SP, Kao KJ, Simbulan KB, Lan YW, Kuan CH. Responsivity and detectivity enhancements by graphene overlay on normal-incident multicolor quantum grid infrared photodetectors. Opt Express 2020; 28:2456-2465. [PMID: 32121935 DOI: 10.1364/oe.384379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/08/2020] [Indexed: 06/10/2023]
Abstract
An efficient and effective method to achieve high responsivity and specific detectivity, particularly for normal-incident quantum well infrared photodetectors (QWIPs), is proposed in this study. By combining superlattice (SL) structure, grating structures, and graphene monolayer onto traditional QWIP designs, a graphene-covered multicolor quantum grid infrared photodetector (QGIP) with improved optoelectrical properties is developed. The enhancements of the device's responsivity and specific detectivity are about 7-fold and 20-fold, respectively, which resulted from an increase in the charge depletion region and the generation of extra photoelectrons due to graphene-semiconductor heterojunction. This method provides a potential candidate for future high-performance photodetectors.
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Yang SC, Lu LF, Cai Y, Zhu JB, Liang BW, Yang CZ. Body distribution in mice of intravenously injected camptothecin solid lipid nanoparticles and targeting effect on brain. J Control Release 1999; 59:299-307. [PMID: 10332062 DOI: 10.1016/s0168-3659(99)00007-3] [Citation(s) in RCA: 276] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The objective of the present study was to investigate the specific drug targeting of anticarcinogenic drugs, such as camptothecin (CA), after intravenous (i.v.) injection by incorporation into solid lipid nanoparticles (SLN). A CA loaded SLN suspension consisted of 0.1% (w/w) camptothecin, 2.0% (w/w) stearic acid, 1.5% (w/w) soybean lecithin and 0.5% (w/w) polyoxyethylene-polyoxypropylene copolymer (Poloxamer 188) was prepared by high pressure homogenization. In vitro drug release was investigated in pH 7.4 phosphate-buffered saline at 37 degrees C. The concentrations of camptothecin in various organs were determined using reversed-phase high-performance liquid chromatography with a fluorescence detector after i.v. administration of CA-SLN and a camptothecin control solution (CA-Sol). The results showed that the CA-SLN had an average diameter 196.8 nm with a Zeta potential of -69.3 mV and in vitro drug release was achieved for up to a week. In tested organs, the AUC/dose and the mean residence times (MRT) of CA-SLN were much higher than those of CA-Sol, especially in brain, heart and reticuloendothelial cells containing organs. The brain AUC ratio of CA-SLN to CA-Sol was the highest among the tested organs. These results indicate that SLN are a promising sustained release and drug targeting system for lipophilic antitumour drugs, and may also allow a reduction in dosage and a decrease in systemic toxicity.
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Affiliation(s)
- S C Yang
- Department of Polymer Science and Engineering, College of Chemistry and Engineering, Nanjing University, Nanjing 210093, People's Republic of China
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Mao XM, Liang BW, Yao YP, Fang SZ, Li Q. [Effect of pulse current iontophoretic transdermal delivery of insulin on blood glucose in diabetic rats]. Yao Xue Xue Bao 1995; 30:881-885. [PMID: 8712012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Iontophoresis of pulse current with various current intensity, frequency, on/off ratio and duration of treatment was used to facilitate the transdermal delivery of insulin in order to control blood glucose levels in diabetic rats. Male Sprague-Dawley rats were made diabetic by i.p. injection of streptozotocin (65 mg . kg-1 body weight). After two days, diabetic rats were anaesthetized with urethane (as 25% aqueous solution, 1.5 mg . g-1). Both the reservoir electrodes and the receptor electrodes were applied on the abdominal site of the diabetic rats. Iontophoresis was carried out using a prototype transdermal periodic iontophoretic system in order to provide the required direct current with desired pulse modes. The extent of reduction of blood glucose levels was found to be positively correlated with the current intensity, frequency and duration of treatment to some extent. But when the current intensity was over 0.8 mA/cm2 and the frequency was over 3000 Hz, the reduction of blood glucose levels did not continuously increase. Blood glucose levels were found to be better controlled when the on/off ratio of 1 : 1 was used.
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Affiliation(s)
- X M Mao
- Chinese PLA No. 454 Hospital, Nanjing
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Dreszer P, Chen WM, Seendripu K, Wolk JA, Walukiewicz W, Liang BW, Tu CW, Weber ER. Phosphorus antisite defects in low-temperature InP. Phys Rev B Condens Matter 1993; 47:4111-4114. [PMID: 10006545 DOI: 10.1103/physrevb.47.4111] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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