Search

This study applied the information processing view and the concept of fit to improve understanding of how attachment behaviour and continued use in mobile social network game (M-SNG) players is affected by the alignment between their motivation and technological capability. A quantitative method and a cross-sectional study design were used to evaluate the research model. Data were collected for 427 active M-SNG players in Taiwan. The proposed model was tested with fit as a covariation and with fit as a propensity score in matching method. The results of this study verified that (1) coalignment between motivation and technological capability is positively associated with attachment behaviour in M-SNG players; (2) M-SNG players who have a high coalignment between motivation and technological capability have stronger attachment behaviour compared to players with low coalignment; and (3) attachment behaviour is positively associated with continued use of M-SNGs. This study contributes to the literature by improving understanding of the antecedents of attachment and continued use in M-SNG players. For providers and developers, this study also provides insights into how to improve the business performance of M-SNGs.

Purpose Research in tourism and hospitality industry marketing has identified many highly effective applications of social media. However, studies in the existing literature do not enable a comprehensive understanding of this phenomenon because they lack a theoretical foundation. Therefore, this study systematically reviewed the literature from the perspective of the task-technology fit (TTF) theory. The purpose of this paper is to map out what is known about social media use in tourism and hospitality marketing and what areas need further exploration. Design/methodology/approach A descriptive cumulative review of the literature obtained 99 articles published in tourism and hospitality journals from 2010 to 2019. Findings The analysis suggests that to understand social media use in tourism marketing, researchers and practitioners in the industry must clarify the following four issues: the control variables, longitudinal analyzes and TTF concepts that should be used in future studies; the fitness of social media platforms for tourism marketing; how various social media platforms differ in terms of performance outcome; and the digital divide in the use of social media for tourism. Originality/value An integrated framework was developed to identify constructs and to understand their relationships. Recent studies in this domain are discussed; theoretical and practical suggestions and implications for future research are given.

An inverted-type InAlAs/InAs metal-oxide-semiconductor high-electron-mobility transistor (MOS-HEMT) with liquid phase oxidized (LPO) InAlAs as the gate insulator is demonstrated. A thin InAs layer is inserted in the sub-channel layers of InGaAs to enhance the device performance. The proposed inverted-type InAlAs/InAs MOS-HEMT exhibits an improved maximum drain current density, higher transconductance, lower leakage current density, suppressed noise figures, and enhanced associated gain compared to the conventional Schottky-gate HEMT. Employing LPO to generate MOS structure improves the surface states and enhances the energy barrier. These results reveal that the proposed inverted-type InAlAs/InAs MOS-HEMT can provide an alternative option for device applications.

Hsien-Cheng Lin,1 Chia-Chen Chen2 1Business College, Taizhou University, Taizhou, Zhejiang Province, People’s Republic of China; 2Department of Anesthesiology, China Medical University Hsinchu Hospital, Zhubei, Taiwan, Republic of ChinaCorrespondence: Hsien-Cheng LinBusiness College, Taizhou University, No. 1139, Shifu Avenue, Taizhou, Zhejiang Province, People’s Republic of ChinaEmail linxianzheng0711@tzc.edu.cnChia-Chen ChenDepartment of Anesthesiology, China Medical University Hsinchu Hospital, No. 199, Sec.1, Xinglong Road, Zhubei, Hsinchu Country, 302, Taiwan, Republic of ChinaEmail d7635@mail.cmuhch.org.twObjective: The COVID-19 outbreak has become a serious public health problem worldwide. The purpose of this study was to use an extended parallel process model (EPPM) to understand factors in COVID-19 prevention behaviors.Methods: This cross-sectional and analytical study was conducted on 1012 participants in Taiwan. A structured questionnaire and an online survey were used to collect data.Results: The EPPM revealed that the severity of the COVID-19 threat perceived by respondents directly affected the arousal of fear in the respondents (β=0.268, t=9.007, p< 0.001), but perceived efficacy did not (β=− 0.019, t=− 0.619, p> 0.05); additionally, fear arousal was significantly associated with COVID-19 prevention behaviors (β=0.119, t=4.603, p< 0.001). Regarding personal characteristics, self-esteem moderated the relationship between perceived threat and fear arousal. However, the moderating effect of self-esteem was stronger in people with low self-esteem compared to those with high self-esteem (β=0.606, − 0.472; t=26.303, − 17.694; p< 0.001, p< 0.001; respectively). The results of this study also indicated that two demographic characteristics (age and gender) affect COVID-19 prevention behaviors.Conclusion: When developing healthcare policies and community interventions for improving COVID-19 prevention behaviors during an outbreak, healthcare administrators should carefully consider the main constructs of the EPPM, particularly personal characteristics (ie, self-esteem) and demographic characteristics (ie, age and gender).Keywords: COVID-19, extended parallel process model, perceived threat, perceived efficacy, prevention behavior

Hospitals in Taiwan are facing major changes and innovation is increasingly becoming a critical factor for remaining competitive. One determinant that can have a significant impact on innovation is hospital governance. However, there is limited prior research on the relationship between hospital governance and innovation. The purpose of this study is to propose a conceptual framework to hypothesize the relationship between governance mechanisms and innovation and to empirically test the hypotheses in hospital organizations. We examine the relationship between governance mechanisms and innovation using data on 102 hospitals in Taiwan from the Taiwan Joint Commission on Hospital Accreditation and Quality Improvement. We model governance mechanisms using board structure, information transparency and strategic decision-making processes. For our modeling and data analysis we use measurement and structural models. We find that in hospital governance, information transparency and strategic decision making did impact innovation. However, governance structure did not. To facilitate innovation, hospital boards can increase information transparency and improve the decision-making process when considering strategic investments in innovative initiatives. To remain competitive, hospital boards need to develop and monitor indices that measure hospital innovation to ensure ongoing progress.

This study aims to explore the influence of national cultural differences on nurses' perceptions of their acceptance of hospital information systems. This study uses the perspective of Technology Acceptance Model; national cultural differences in terms of masculinity/femininity, individualism/collectivism, power distance, and uncertainty avoidance are incorporated into the Technology Acceptance Model as moderators, whereas time orientation is a control variable on hospital information system acceptance. A quantitative research design was used in this study; 261 participants, US and Taiwan RNs, all had hospital information system experience. Data were collected from November 2013 to February 2014 and analyzed using a t test to compare the coefficients for each moderator. The results show that individualism/collectivism, power distance, and uncertainty avoidance all exhibit significant difference on hospital information system acceptance; however, both masculinity/femininity and time orientation factors did not show significance. This study verifies that national cultural differences have significant influence on nurses' behavioral intention to use hospital information systems. Therefore, hospital information system providers should emphasize the way in which to integrate different technological functions to meet the needs of nurses from various cultural backgrounds.

Purpose – Drawing upon the literature of Uses and Gratifications (U & G) Theory, the purpose of this paper is to propose that entertainment, information seeking, socialization, and self-presentation are the motivational factors affecting continuance intention of social media. This paper further investigates the moderating effects of cultural difference and socio-economic status on the link between these motivational factors and continuance intention. Design/methodology/approach – Data collected from the 493 active users of Facebook in five countries (Australia, Austria, Japan, Taiwan, and the USA) were used to test the proposed model. Partial least squares method was used to assess the relationships in the model and the subgroup analysis method was employed as well to examine the moderating roles of cultural difference and socio-economic status. Findings – Information seeking exerts stronger effect on continuance intention for users from individualistic cultures, while socialization, and self-presentation has stronger influence on continuance intention for users from collective cultures. Entertainment has stronger influence on continuance for high educated users, whereas self-presentation has stronger influence on continuance intention for users with lower level of education. Finally, the effect of entertainment, information seeking on continuance intention is stronger for users with higher level of income, while self-presentation has stronger influence on continuance intention for users with lower level of income. Originality/value – This study is one of first studies to extend the research context of U & G Theory from adoption of social media to continuance intention of social media. This study is also the first to investigate the moderating roles of cultural difference and socio-economic statuses in social media usage behavior simultaneously.

Enhancement-mode In0.53Ga0.47As n-type metal-oxide-semiconductor field-effect transistors (MOSFETs), with barium zirconate titanate (BZT) and titanium dioxide (TiO2) high-κ materials prepared via the solution–gelation process as gate dielectrics, have been fabricated. The dielectric constants of BZT and TiO2 are 6.67 and 19.3, respectively. The In0.53Ga0.47As MOSFET with TiO2 exhibits better electrical characteristics than the In0.53Ga0.47As MOSFET with BZT. These characteristics include higher maximum drain current density, higher maximum transconductance, and smaller subthreshold swing.

The medical tourism literature lacks insight into related issues of these types of partnerships. Those that integrate multiple perspectives into one research framework are especially rare. This stu...

The previous literature provides evidence that the characteristics of a successful computer system and the informatics competencies of individuals play a critical role in the adoption of information technology. However, while the combined effects of the two may provide a comprehensive view in understanding nursing informatics research, they have rarely been studied simultaneously. Therefore, this study aimed to examine the influences of computer system success and informatics competencies on nursing organizational impact. We surveyed 454 nurses who worked at international patient centers in Taiwan. The results show that both nurses' informatics competencies and nursing computer system success do have influence on nursing organizational impact. Moreover, nurses' informatics competencies have a greater effect than the superior characteristics of a nursing computer system on nursing organizational performance. Finally, implications for practitioners complete this study.

Nursing information systems can enhance nursing practice and the efficiency and quality of administrative affairs within the nursing department and thus have been widely considered for implementation. Close alignment of human-computer interaction can advance optimal clinical performance with the use of information systems. However, a lack of introduction of the concept of alignment between users' perceptions and technological functionality has caused dissatisfaction, as shown in the existing literature. This study provides insight into the alignment between nurses' perceptions and how technological functionality affects their satisfaction with Nursing Information System use through a reductionist perspective of alignment. This cross-sectional study collected data from 531 registered nurses in Taiwan. The results indicated that "perceived usefulness in system quality alignment," "perceived usefulness in information quality alignment," "perceived ease of use in system quality alignment," "perceived ease of use in information quality alignment," and "perceived ease of use in service quality alignment" have significantly affected nurses' satisfaction with Nursing Information System use. However, "perceived usefulness in service quality alignment" had no significant effect on nurses' satisfaction. This study also provides some meaningful implications for theoretical and practical aspects of design.

InGaP/InGaAs metal–oxide–semiconductor (MOS) pseudomorphic high-electron-mobility transistor (PHEMT) with a nanoscale liquid phase-oxidized InGaP as the gate dielectric is demonstrated. Not only does the MOS-PHEMT have the advantages of the MOS structure, but it also has high-carrier density and a high-mobility 2DEG channel. Using selective oxidation of InGaP by liquid phase oxidation, the MOS-PHEMT can be fabricated without additional recess processes. The MOS-PHEMT exhibits larger transconductance, lower gate leakage current, higher breakdown voltage, higher cut-off frequency, lower minimum noise figure, and higher power-added efficiency than does its counterpart (reference PHEMT). The interface roughness effect on the DC and RF performance of devices is also discussed.

The study explored titanium dioxide (TiO 2 ) on aluminum gallium arsenide (AlGaAs) prepared by liquid phase deposition (LPD) at 40 °C. The leakage current density was about 8.4 × 10 −6 A/cm 2 at 1 MV/cm. The interface trap density ( D it ) and the flat-band voltage shift (Δ V FB ) were 2.3 × 10 12 cm −2 eV −1 and 1.2 V, respectively. After rapid thermal annealing (RTA) in the ambient N 2 at 350 °C for 1 min, the leakage current density, D it , and Δ V FB were improved to 2.4 × 10 −6 A/cm 2 at 1 MV/cm, 7.3 × 10 11 cm −2 eV −1 , and 1.0 V, respectively. Finally, the study demonstrates the application to the AlGaAs/InGaAs metal–oxide–semiconductor pseudomorphic high-electron-mobility transistor (MOS-PHEMT). The results indicate the potential of the proposed device with a LPD-TiO 2 gate oxide for power application.

Practicing gender-based equal rights is an international trend today. An empirical study was conducted to analyze the individual traits of women and their needs in order to determine how female-friendly hospital environments were by focusing on environments fitted for individuals. A structured questionnaire was distributed to the female users of a model female-friendly hospital recognized by the Health Bureau; 200 questionnaires were issued and 154 replies were valid. Variance and multiple regression analyses were conducted on the valid questionnaires. The results of the study indicate that: (1) the hospital’s efforts to promote a female-friendly hospital environment fell below women’s expectations; (2) when the hospital offered a less female-friendly hospital environment, female patients were less satisfied; and (3) “educational attainment” and “experience of a female-friendly hospital environment” most significantly influence the degree to which female patients would be satisfied with services provided by hospitals. We recommend hospitals educate medical staff and administrators regarding the concept of gender-based equal rights through relevant training in order to cultivate a high level of awareness and enthusiasm for offering female patients more comprehensive services so that they feel respected when receiving medical treatment.

The InGaP/InGaAs metal–oxide–semiconductor pseudomorphic high-electron-mobility transistor (MOS-PHEMT) with an oxidized GaAs gate by liquid phase oxidation (LPO) is demonstrated. With the help of the LPO, the threshold voltage ( V th ) can be shifted positively to 0.07 V, and enhancement-mode MOS-PHEMT is fabricated. The device with a gate metal of 1 × 100 μm 2 shows a maximum transconductance of 171 mS/mm at V DS = 5 V and a maximum drain current density of 182 mA/mm at V GS = 2 V. It also exhibits a lower leakage current and an improved subthreshold swing compared to the referenced Schottky-gate InGaP/InGaAs PHEMT.

In an effort to continually develop potent antiplatelet agents with vasorelaxing and antiinflammatory actions, a novel series of antiinflammatory chalcones was continually screened to evaluate their antiplatelet and vasorelaxing effects. Their structure–activity relationships and mode of action were discussed and characterized. A novel series of antiinflammatory chalcones was studied on antiplatelet effect in rabbit washed platelets and human platelet-rich plasma (PRP) and vasorelaxing effect in rat thoracic aorta. Arachidonic acid-induced platelet aggregation was potently inhibited by almost all the chalcone derivatives and 13–15 also had a potent inhibitory effect on cyclooxygenase. The selective chalcones 12–16 tested in human PRP significantly inhibited secondary aggregation induced by adrenaline. In rat thoracic aorta, most of chalcones at high concentration significantly depressed the contractions induced by Ca2+ (1.9 mM) in high K+ (80 mM) medium and the phasic and tonic contractions caused by norepinephrine (3 μM). In the rat thoracic aorta, the phenylephrine- and high K+-induced 45Ca2+ influx were both inhibited by a selective chalcone derivative, 14. These results indicate that the antiplatelet actions of chalcones are mainly mediated through the suppression of cyclooxygenase activity and reduced thromboxane formation and their inhibitory effects on the contractile response caused by high K+ and norepinephrine in rat thoracic aorta are mainly due to inhibition of Ca2+ influx through both voltage-dependent and receptor-operated Ca2+ channels. Drug Dev. Res. 53:9–14, 2001. © 2001 Wiley-Liss, Inc.

A novel constituent named australone B (1) was further isolated from the cortex of Morus australis (Moraceae). The structure of 1 has been elucidated by one- and two-dimension spectra. In human citrated platelet-rich plasma, 1 showed strong inhibition of aggregation induced by adrenaline in a concentration-dependent manner with an IC(50) value of about 33.3 microM. Compound 1 (30 microM) also showed inhibitory effects on superoxide anion formation from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP)/cytochalasin B (CB). Morusin (2) inhibited superoxide anion formation from rat neutrophils stimulated with phorbol myristate acetate (PMA) in a concentration-dependent manner with an IC(50) value of 66.9+/-2.5 microM.

The stereochemistry of new acetophenones, cynandione B–D ( 2 – 4 ), isolated from Cynanchum taiwanianum , elucidated by computer modelling calculation and NOESY spectrum. It establishes the absolute configurations of cynandiones B–D ( 2 – 4 ) as 7R; 7″S, 7S; 7″S and 7R; 7″R, respectively. Cynandione B ( 2 ) strongly inhibited the release of β-glucuronidase and lysozyme in formyl–methionyl–leucyl–phenylalanine (fMLP)-stimulated rat neutrophils in a concentration-dependent manner with IC 50 values of 1.5±0.2 and 1.6±0.2 μM, respectively. 2,5-Dihydroxyacetophenone ( 6 ) strongly inhibited the aggregation of washed rabbit platelets induced by arachidonic acid in a concentration-dependent manner with an IC 50 value of about 4.8 μM. In human citrated platelet-rich plasma, 2,5-dihydroxyacetophenone ( 6 ) inhibited the secondary phase, but not the primary phase, of aggregation induced by adrenaline and ADP. These results suggest that the antiplatelet effect of 2,5-dihydroxyacetophenone ( 6 ) is due to inhibition of the formation of thromboxane A 2 .

Sixteen constituents from Formosan Moraceous plants were tested for their antiplatelet activities in rabbit platelet suspension and human platelet-rich plasma. Cycloartocarpin A, cycloheterophyllin, broussochalcone A, kazinol A, broussoaurone A, and broussoflavonol F showed strong inhibition of arachidonic acid (AA)-induced platelet aggregation. Of the compounds tested, broussochalcone A exhibited the most potent inhibition of platelet aggregation induced by AA (IC50 = 6.8 microM). The antiplatelet effects of cycloheterophyllin, broussochalcone A, kazinol B, broussoaurone A, and broussoflavonol F are partially due to an inhibitory effect on cyclooxygenase.

A series of ω-aminoalkoxylxanthones were synthesized and tested in-vitro for their ability to inhibit aggregation of rabbit washed platelets and human platelet-rich plasma (PRP) induced by various inducers. Nine of these compounds showed more potent antiplatelet effects than natural norathyriol tetraacetate on collagen-induced aggregation. The various ω-aminoalkoxyl side chains of the synthesized compounds modified the antiplatelet effects. All the compounds tested in human PRP showed significant inhibition of secondary aggregation induced by adrenaline, suggesting that the antiplatelet effects of these compounds is mainly due to an inhibitory effect on thromboxane formation. These compounds at high concentration also cause vasorelaxing action in rat thoracic aorta.

This study examines the feasibility of an enhancement-mode (E-mode) pseudomorphic high-electron-mobility transistor (PHEMT) with a nanoscale oxidized GaAs gate using liquid phase oxidation (LPO). Using LPO, the threshold voltage (V th ) can be shifted positively. Results indicated a reduced leakage current, a higher breakdown voltage, and an improved subthreshold swing compared to those of the Schottky-gate PHEMT. Therefore, LPO did not degrade the DC performance of the device.

2,3- and 3,4-Dihydroxyxanthone react with ethyl 2,3-dibromopropanoate to form the new, substituted 1,4-benzodioxanes 3 and 4, respectively. The regioisomers 3a and 3b; 4a and 4b were separated by column chromatography and characterized for evaluation of the antiplatelet effects in rabbit washed platelets and human platelet-rich plasma. The ethoxycarbonyl derivatives 3a (20 μm) and 3b (20 μm) strongly inhibited the aggregation of rabbit washed platelets induced by arachidonic acid and collagen. The compound 4b showed the most potent inhibition of rabbit washed-platelet aggregation induced by arachidonic acid (IC50 = 8·3 μm). Of the compounds tested in human platelet-rich plasma, compound 4b exhibited the most potent inhibition of primary and secondary aggregation induced by adrenaline (IC50 = 8·6 μm). We conclude that the antiplatelet effects of these four ethoxycarbonyl derivatives are mainly due to an inhibitory effect on thromboxane formation and interference in the adrenaline-receptor interaction.

The liquid phase deposition (LPD) was used to deposit silicon oxide (SiO 2 ) layer on AlGaAs near room temperature. The LPD method is not only simple but also can obtain the SiO 2 very economically. Both the aqueous solution of hydro-fluosilicic acid (H 2 SiF 6 ) and boric acid (H 3 BO 3 ) were used for the LPD solution. After rapid temperature annealing (RTA) at 300°C for 1 min, the leakage current density is ~ 4.24 × 10−7 A/cm2 at 1 MV/cm, and the interface trap density is ~ 1.7 × 1011 cm−2eV−1 for the LPD-SiO 2 thickness of 29 nm.

The known flavonoids ginkgetin (1), taiwanhomoflavone A (2), taiwanhomoflavone B (3), and taiwanhomoflavone C (4) and eight known lignans: justicidin B (9), justicidin C (10), justicidin D (11), chinensinaphthol methyl ether (12), procumphthalide A (13), procumbenoside A (15), and ciliatosides A (16) and B (17) were isolated from Cephalotaxus wilsoniana and Justicia species, respectively. The antiplatelet effects of the above constituents on human platelet-rich plasma (PRP) were evaluated. Of the compounds tested on human PRP, compounds 1, 4, 9, and 11 showed inhibition of secondary aggregation induced by adrenaline. Compound 1 had an inhibitory effect on cyclooxygenase-1 (COX-1). Molecular docking studies revealed that 1 and the related compounds apigenin (5), cycloheterophyllin (6), broussoflavone F (7), and quercetin (8) were docked near the gate of active site of COX-1. It indicated that the antiplatelet effect of 1, 4, 9, and 11 is partially owed to suppression of COX-1 activity and reduced thromboxane formation. Flavonoids, 1, 5, 6, 7, and 8 may block the gate of the active site of COX-1 and interfere the conversion of arachidonic acid to prostaglandin (PG) H2 in the COX-1 active site.

Objectives: This study was undertaken to investigate if there is a disparity in the antioxidant status and the ability of superoxide anion (O 2 ·- ) generation in the patients with acute myeloid leukemia (AML). Design and methods: The peripheral blood samples from thirty AML patients and thirty-six healthy subjects were collected and leukocytes, erythrocytes and plasma were separated for use in various parameter measurements. Results: The generation of O 2 ·- , as reflected by lucigenin-based CL (LBCL), by the leukocytes of patients with AML was found to be significantly elevated either in resting or stimuli-elicited condition as compared with that of healthy controls (p< 0.05). Coincidentally, these data were matched up with the suppressed SOD activities, notably in Cu/Zn SOD isoform found in AML patients (p< 0.05). Conversely, SOD and GPx activities in erythrocytes of patients with AML were shown to be significantly higher than their normal counterparts (p

Four flavonoids, dihydroartomunoxanthone (1), artomunoisoxanthone (2), cyclocomunomethonol (3) and artomunoflavanone (4), together with three known compounds, artochamins B (5), D and artocommunol CC (6) were isolated from the cortex of the roots of Artocarpus communis. The structures of 1-4 were determined by spectroscopic methods. The antiplatelet effects of the flavonoids, 1-3, 5 and 6 on human platelet-rich plasma (PRP) were evaluated. Of the compounds tested in human PRP, compounds 1, 5 and 6 showed significant inhibition of secondary aggregation induced by adrenaline. It is concluded that the antiplatelet effect of 1, 5 and 6 is mainly owing to an inhibitory effect on thromboxane formation.

THz radiation from series of GaAs and InAlAs surface intrinsic-N + (SIN + ) structures with the built-in electric field as bias is studied. When the bias exceeds the so-called critical electric field, the amplitude of THz waves radiated is independent of the built-in electric field. However, the THz amplitude is proportional to the number of photo-excited free charged carriers and thus the thickness of the intrinsic layer of the SIN + structures. The critical electric field determined from the THz amplitude as a function of the electric field may be useful in estimating the Γ to L valley splitting in semiconductors. Lattice-matched GaAs and In0.52Al0.48As surface intrinsic-N + (SIN + ) structures with various thicknesses of intrinsic layers grown by conventional molecular beam epitaxy are used as the THz emitters in this study. The built-in electric field is used as the bias. The as-grown heterosturctures possess a common structure consisting of various thicknesses of undoped layers on top of 1 µm of a Si-doped, n-type buffer layer that have been grown previously on an Fe-doped semi-insulated (100) substrate. The doping concentration in the buffer layer is approximately 8.4×10 17 cm -3 . Samples with various undoped layer thicknesses are also obtained from as-grown samples by subsequent etches. The built-in electric field is determined as a function of the thickness of the intrinsic layers using modulation spectroscopy of photoreflectance (PR). Figure 1a) displays the THz waves radiated from SI (100) GaAs wafer, and GaAs and In0.52Al0.48As SIN + structures. Figure 1b) plots THz waves in the frequency domain obtained by applying the fast Fourier transform to the THz waves in the time domain. The amplitude of the THz wave from the In0.52Al0.48As SIN + structure with an intrinsic layer of 2000A is five times of that from the SI GaAs wafer. Figure 2 plots the amplitude of the THz radiation from In0.52Al0.48As and GaAs SIN + structures as a function of the thickness of the intrinsic layer. Figure 3 depicts the built-in electric field, determined from PR spectra in our previous studies, as a function of the thickness of the intrinsic layer. 5-7 The negative values of thickness represent the thickness of the buffer layer that has been etched away, therefore; the built-in electric field in these samples locates within the charge depletion layer. Figures 2 and 3, however, reveal that the amplitude of the THz radiation is independent of the built-in electric fields in the emitters but is proportional to the thickness of the intrinsic layer of the SIN + structure. This behavior is interpreted

Two new arylnaphthalide lignans, procumphthalide A (1) and 4-O-beta-D-glucopyranosyl-(1"'-->2")-beta-D-apiofuranosyldiphyllin, named procumbenoside B (2), along with cilinaphthalide B (3) and several other known compounds were isolated from the methanolic extracts of Justicia procumbens. By using NMR and other spectral methods, the structures of 1 and 2 were elucidated. Cilinaphthalide B (3), justicidin A (4), and taiwan E methyl ether (5) were shown to have an antiplatelet effect in human plateletrich plasma. In human citrated PRP, 5 showed a strong inhibitory effect on platelet aggregation induced by adrenaline in a concentration-dependent manner, with an IC(50) value of about 27.6 microM.

We describe a practical train scheduling system (called TSS) designed for the Taiwan Railway Bureau (TRB). TSS has two major components. The first is Auto Scheduler which includes an initial scheduler, a conflict finder, and a conflict resolver. Auto Scheduler uses the concept of bugging as problem solving tactics. The second is Manual Scheduler which provides some effective editing functions for users to tune schedules generated by Auto Scheduler. Through an easy-to-use user interface, these components can be used to solve large-scale complex train scheduling problems. >

A series of flavones and flavonoxypropanolamines were synthesized and tested in-vitro for their ability to inhibit aggregation of washed rabbit platelets and human platelet-rich plasma (PRP), and for vasoconstriction of rat thoracic aorta. The various substituted positions of the hydroxyl group in flavone ring B and the various oxypropanolamine side chains substituted at position C-2′ of flavone modified the antiplatelet effects. All the compounds tested in human PRP showed significant inhibition of secondary aggregation induced by adrenaline (epinephrine), suggesting that the antiplatelet effect of these compounds is mainly due to an inhibitory effect on thromboxane formation. Compounds 11 and 12 also had potent vasorelaxant effects in rat thoracic aorta. Phenylephrine- and high-K+-induced 45Ca2+ influx in aorta were both inhibited by the selected compound 11. This result indicates that the inhibitory effect of 11 on the contractile response caused by high-K+ medium and noradrenaline (norepinephrine) in rat thoracic aorta is mainly due to inhibition of Ca2+ influx through both voltage-dependent and receptor-operated Ca2+ channels.

A series of xanthone derivatives was synthesized and tested in-vitro for their ability to inhibit aggregation of rabbit washed platelets and human platelet-rich plasma (PRP) induced by various inducers. 2-Prenyloxyxanthone showed the most potent inhibition of rabbit washed platelet aggregation induced by arachidonic acid (IC50 = 10.2 μM). Of the compounds tested in human PRP, 2-[3 (propylamino)-2-hydroxypropoxy]xanthone (4) hydrochloride salt exhibited the most potent inhibition of platelet aggregation induced by adrenaline (IC50 = 4.4 μM), whereas in evaluation of mouse antithrombotic activity, compound 4 exhibited the most potent protection of mice from thrombotic challenge. Compound 4, 2-[3-(isopropylamino)-2-hydroxypropoxylxanthone hydrochloride salt and 2,5 dihydroxyxanthone suppressed the secondary aggregation induced by adrenaline in human PRP. We conclude that the antiplatelet effects of these compounds are mainly due to an inhibitory effect on thromboxane formation.

A new naphthalene derivative, isotorachrysone [1], was isolated from the stem bark of Rhamnus nakaharai along with several known compounds. The antiplatelet effects of isotorachrysone [1], isotorachrysone peracetate [2], 6-methoxysorigenin [3], quercetin 3-O-methyl ether [4], and quercetin 3-O-methyl ether peracetate [5] were studied using washed rabbit platelets. Of the compounds tested, 1, 2, 4, and 5 showed potent antiplatelet effects on arachidonic acid (AA-) and collagen-induced platelet aggregation. Compound 5 also showed potent antiplatelet effects on platelet-activating factor-(PAF-) induced platelet aggregation. Isotorachrysone [1] and its peracetate [2] were also studied for antiplatelet activity in human platelet-rich plasma (PRP) and both showed potent inhibition of the secondary aggregation induced by epinephrine. The antiplatelet effects of 1 and 2 are due partially to an inhibitory effect on thromboxane formation.

The bandgap, surface Fermi level, and surface state density of a series of GaAs1−xSbx surface intrinsic-n+ structures with GaAs as substrate are determined for various Sb mole fractions x by the photoreflectance modulation spectroscopy. The dependence of the bandgap on the mole composition x is in good agreement with previous measurements as well as predictions calculated using the dielectric model of Van Vechten and Bergstresser in Phys. Rev. B 1, 3551 (1970). For a particular composition x, the surface Fermi level is always strongly pinned within the bandgap of GaAs1−xSbx and we find its variation with composition x is well described by a function EF = 0.70 − 0.192 x for 0 ≦ x ≦ 0.35, a result which is notably different from that reported by Chouaib et al. [Appl. Phys. Lett. 93, 041913 (2008)]. Our results suggest that the surface Fermi level is pinned at the midgap of GaAs and near the valence band of the GaSb.

not Available.