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Sleep deprivation adversely affects the digestive system. Multiple studies have suggested sleep deprivation and oxidative stress are closely related. Autophagy can be triggered by oxidative stress as a self-defense strategy to promote survival. In this study, we investigated the effects of sleep deprivation on liver functions, oxidative stress, and concomitant hepatocyte autophagy, as well as the associated pathways. Enzymatic and nonenzymatic biochemical markers in the serum were used to assess hepatic function and damage. To evaluate the occurrence of autophagy, expression of autophagy-related proteins was tested and autophagosomes were labeled. Additionally, methane dicarboxylic aldehyde (MDA), antioxidant enzymes, and the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway were analyzed using chemical methods and a Western blot. Serum alanine transaminase, aspartate aminotransferase, and alkaline phosphatase increased in sleep-deprived rats. Total protein and albumin abundance was also abnormal. Sleep deprivation induced histopathological changes in the liver. The superoxide dismutase level decreased significantly in the liver of sleep-deprived rats. In contrast, the MDA content increased in the sleep deprivation group. Moreover, the microtubule-associated protein 1 light chain 3 beta (LC3B) II/I ratio and Beclin I content increased considerably in the sleep-deprived rats, while p62 levels decreased. Sleep deprivation apparently inhibited the AKT/mTOR signaling pathway. We conclude that sleep deprivation can induce oxidative stress and ultimately cause liver injury. Autophagy triggered by oxidative stress appears to be mediated by the AKT/mTOR pathway and plays a role in relieving oxidative stress caused by sleep deprivation.

To investigate the influence of deep slow-wave sleep deprivation on the oxidative stress of testicular tissue in rats.Thirty-six 5-week-old male Wistar rats were equally randomized into deep slow-wave sleep deprivation group (SD1), deep slow-wave sleep and duration sleep deprivation group ( SD2), and a cage control group (CC). The rat model of deep slow-wave sleep deprivation was established using the flowerpot technique. The rats in the SD1 group were interfered every 24 minutes and deprived of 12 hours of sleep at night, those in the SD2 group deprived of 8 minutes of sleep at an interval of 24 minutes and 12 hours of sleep at night, and those in the CC group exposed to 12 hours of daylight and 12 hours of darkness. After 28 days, all the rats were executed for measurement of the testis volume and protein content, determination of the methane dicarboxylic aldehyde (MDA) level and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and observation of the pathological changes in the testicular tissue under the microscope.Compared with the CC group, the rats in the SD1 and SD2 groups showed significantly reduced body weight (［268.5 ± 1.6］ vs ［248.1 ± 25.1］and［232.9 ± 10.1］g, P0.05) and increased relative testis mass (［50.0 ± 1.3］ vs ［57.9 ± 6.1］ and ［54.9 ± 3.5］ ×10⁻², P0.05). Statistically significant differences were found between the CC and SD2 groups in the contents of protein (［6.3 ± 1.4］ vs ［4.5 ± 0.9］ gpro/L, P0.05) and MDA (［1.1 ± 0.1］ vs ［1.3 ± 0.3］ nmol/mgpro, P0.05) and the activities of SOD (［104.3 ± 33.1］ vs ［135.2 ± 26.9］ U/mgpro, P0.05) and GSH-Px (［15.6 ± 4.0］ vs ［21.7 ± 4.3］ U/mgpro, P0.05), but not between the CC and SD1 groups (P0.05). The lumens in the testis were narrowed, with obvious hyperplasia, hyperemia and edema in the peripheral interstitial tissue, but no significant pathologic changes were observed in the testis tissue of the SD1 group.Long-term deprivation of deep slow-wave sleep impairs the structure of the testis tissue and induces oxidative stress response in rats.目的：研究深慢波睡眠剥夺对大鼠睾丸组织氧化应激反应的影响。 方法：36只5周龄健康雄性Wistar大鼠，随机分为深慢波睡眠时相剥夺组（SD1组）、深慢波睡眠时相及时长剥夺组（SD2组）组和空白对照组（CC组），每组12只，利用小平台水环境建立深慢波睡眠剥夺模型。SD1组每间隔24 min干扰1次，SD2组每间隔24 min剥夺睡眠8 min；夜间都进行12 h的完全睡眠剥夺。CC组模拟正常的12 h光照、12 h黑暗时间。28 d后，大鼠股动脉放血，留取睾丸组织进行称重，测定睾丸组织中蛋白含量、丙二醛（MDA）、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物岐化酶（SOD）水平，显微镜下观察睾丸病理结构的改变。结果：SD1、SD2组大鼠的终末体质量［（248.1±25.1） g、（232.9±10.1） g］均下降，与CC组［（268.5± 1.6）g］相比差异有统计学意义（P均0.05）；与CC组相比，SD2组睾丸相对质量明显升高［（54.9±3.5）×10⁻² vs （50.0±1.3）×10⁻²，P0.05］。与CC组相比，SD2组睾丸组织蛋白含量、MDA含量、SOD活性和GSH-Px均有显著差异［蛋白含量：（4.5±0.9）g pro/L vs 6.3±1.4）g pro/L； MDA含量: （1.3±0.3）nmol/mg pro vs （1.1±0.1）nmol/mg pro；SOD活性：（135.2±26.9）U/mg pro vs （104.3±33.1）U/mg pro； GSH-Px活性： （21.7±4.3）U/mg pro vs（15.6±4.0）U/mg pro，P均0.05］，而与SD1组比较差异无统计学意义。SD1组睾丸病理学改变不明显，但SD2组睾丸生精小管管腔变小，周围间质部分增加，间质充血水肿明显。结论：长期深慢波睡眠剥夺对大鼠睾丸组织结构产生损伤并引起氧化应激反应。.

Deep ultraviolet (UV) light sources are useful in a number of applications that include sterilization, medical diagnostics, as well as chemical and biological identification. However, state-of-the-art deep UV light-emitting diodes and lasers made from semiconductors still suffer from low external quantum efficiency and low output powers. These limitations make them costly and ineffective in a wide range of applications. Deep UV sources such as lasers that currently exist are prohibitively bulky, complicated, and expensive. This is typically because they are constituted of an assemblage of two to three other lasers in tandem to facilitate sequential harmonic generation that ultimately results in the desired deep UV wavelength. For semiconductor-based deep UV sources, the most challenging difficulty has been finding ways to optimally dope the (Al,Ga)N/GaN heterostructures essential for UV-C light sources. It has proven to be very difficult to achieve high free carrier concentrations and low resistivities in high-aluminum-containing III-nitrides. As a result, p-type doped aluminum-free III-nitrides are employed as the p-type contact layers in UV light-emitting diode structures. However, because of impedance-mismatch issues, light extraction from the device and consequently the overall external quantum efficiency is drastically reduced. This problem is compounded with high losses and low gain when one tries to make UV nitride lasers. In this thesis, we provide a robust and reproducible approach to resolving most of these challenges. By using a liquid-metal-enabled growth mode in a plasma-assisted molecular beam epitaxy process, we show that highly-doped aluminum containing III-nitride films can be achieved. This growth mode is driven by kinetics. Using this approach, we have been able to achieve extremely high p-type and n-type doping in (Al,Ga)N films with high aluminum content. By incorporating a very high density of Mg atoms in (Al,Ga)N films, we have been able to show, by temperature-dependent photoluminescence, that the activation energy of the acceptors is substantially lower, thus allowing a higher hole concentration than usual to be available for conduction. It is believed that the lower activation energy is a result of an impurity band tail induced by the high Mg concentration. The successful p-type doping of high aluminum-content (Al,Ga)N has allowed us to demonstrate operation of deep ultraviolet LEDs emitting at 274 nm. This achievement paves the way for making lasers that emit in the UV-C region of the spectrum. In this thesis, we performed preliminary work on using our structures to make UV-C lasers based on photonic crystal nanocavity structures. The nanocavity laser structures show that the threshold optical pumping power necessary to reach lasing is much lower than in conventional edge-emitting lasers. Furthermore, the photonic crystal nanocavity structure has a small mode volume and does not need mirrors for optical feedback. These advantages significantly reduce material loss and eliminate mirror loss. This structure therefore potentially opens the door to achieving efficient and compact lasers in the UV-C region of the spectrum.

The Monascus species has been used in foods for thousands of years in China. In this study, 10 azaphilone pigments, including four yellow and six orange pigments, were isolated from the fermented rice and dioscorea of Monascus purpureus NTU 568. By employing lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells, we determined the inhibitory activities of these pigments on nitric oxide (NO) production. As a result, four orange pigments, monaphilols A-D, showed the highest activities (IC50 = 1.0-3.8 μM), compared with the other two orange pigments, monascorubrin (IC5040 μM) and rubropunctatin (IC50 = 21.2 μM), and the four yellow pigments ankaflavin (IC50 = 21.8 μM), monascin (IC50 = 29.1 μM), monaphilone A (IC50 = 19.3 μM), and monaphilone B (IC50 = 22.6 μM). Using Western blot and ELISA kits, we found that treatments with 30 μM of the yellow pigments and 5 μM of the orange pigments could down-regulate the protein expression of inducible nitric oxide synthase (iNOS) and suppress the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). We also used two animal experiments to evaluate the anti-inflammatory effects of these pigments. In a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema model, eight of these pigments (0.5 mg/ear) could prevent ear edema against TPA administrations on the ears of BALB/c mice. In an LPS-injection mice model, several of these pigments (10 mg/kg) could inhibit the NO, TNF-α, IL-1β, and IL-6 levels in the plasma of BALB/c mice. As concluded from the in vitro and in vivo studies, six azaphilonoid pigments, namely, ankaflavin, monaphilone A, and monaphilols A-D, showed high potential to be developed into chemopreventive foods or drugs against inflammation-associated diseases.

Red mold dioscorea (RMD) is a fermented product of Monascus purpureus NTU 568 using dioscorea as culture substrate. To investigate the bioactive components of RMD, six orange pigments including four new azaphilones with yellow fluorescence, monapilol A-D (1-4), and known monascorubrin (5) and rubropunctatin (6) were isolated and characterized. Structural elucidation of new isolates was based on nuclear magnetic resonance ((1)H NMR, (13)C NMR, COSY, HMQC, and HMBC) and other spectroscopic analyses. The structures of monapilols (1-4) were similar to those of monascorubrin (5) and rubropunctatin (6); however, the hydroxyl group (8-OH) in compounds 1-4 substituted for the C-8 carbonyl in compounds 5 and 6. Biological evaluation indicated that compounds 1-4 inhibited nitric oxide (NO) production on lipopolysaccharide-stimulated RAW 264.7 cells. Compounds 1-4 also exhibited antiproliferative activities against human laryngeal carcinoma (HEp-2) and human colon adenocarinoma (WiDr).

Monascus purpureus NTU 568 was a mutant strain from M. purpureus HM105. The methanol extract of red mold rice fermented by this strain exhibited four major yellow pigment signals on HPLC profile. By repeated chemical chromatography methods, three new azaphilone derivatives, namely, monaphilone A (1), B (2) and C (3), along with the known pigments ankaflavin (4) and monascin (5), were isolated and characterized. Based on spectroscopic analyses, mainly 1D and 2D NMR data, the structures of compounds 1-3 were completely elucidated; in addition, 1-3 were determined to be new azaphilone structures, due to the decrease of carbon monoxide for producing a gamma-lactone ring, compared with other azaphilone derivatives. Biological evaluations showed that monaphilone A (1) and B (2) exhibited an antiproliferative effect against HEp-2 (human laryngeal carcinoma cell line) and WiDr (human colon adenocarcinoma cell line), and none of the five compounds had toxicity to normal human lung cell lines (WI-38 and MRC-5) at 70 muM.

Doping of high aluminum-containing (Al,Ga)N thin films has remained a challenging problem that has hindered progress in the development of deep ultraviolet light-emitters. This paper reports on the synthesis and use of heavily doped (Al,Ga)N films in deep ultraviolet (∼274 nm) light-emitting structures; these structures were synthesized by molecular beam epitaxy under liquid-metal growth conditions that facilitate the incorporation of extremely high density of Mg dopant impurities (up to 5 × 1019 cm−3) into aluminum-rich (Al,Ga)N thin films. Prototypical light-emitting diode structures incorporating Al0.7Ga0.3N films doped with Mg impurities that ionize to give free hole carrier concentrations of up to 6 × 1017 cm−3 exhibit external quantum efficiencies of up 0.56%; this is an improvement from previous devices made from molecular beam epitaxy-grown materials. This improvement is believed to be due to the high hole carrier concentration enabled by the relatively low activation energy of 220 meV compared to...

The group III-nitride (InN, GaN, and AlN) class of semiconductors has become one of two that are critical to a number of technologies in modern life—the other being silicon. Light-emitting diodes made from (In,Ga)N, for example, dominate recent innovations in general illumination and signaling. Even though the (In,Ga)N materials system is fairly well established and widely used in advanced devices, challenges continue to impede development of devices that include aluminum-containing nitride films such as (Al,Ga)N. The main difficulty is efficient doping of films with aluminum-rich compositions; the problem is particularly severe for p-type doping, which is essential for Ohmic contacts to bipolar device structures. This review briefly summarizes the fundamental issues related to p-type doping, and then discusses a number of approaches that are being pursued to resolve the doping problem or for circumventing the need for p-type doping. Finally, we discuss an approach to doping under liquid-metal-enabled gro...

Four new labdane diterpene glycosides (1-4) named alpindenosides A, B, C, and D, two new norditerpene glycosides (5, 6) named noralpindenosides A and B, and three known flavonoid glycosides (7-9) have been isolated from the stems of Alpinia densespicata. Structural elucidation of compounds 1-6 was based on spectroscopic data. Compounds 1-9 all exhibited moderate NO inhibitory activities, whereas they were noncytotoxic at 20 microM against several human tumor cell lines.

Three types of self-assembled ZnOx quantum dots (QDs) or islands on silicon substrates with distinctive morphologies were successfully synthesized using various growth schemes in a simple magnetron sputter. If hydrogen/argon was employed as the sputtering gas under negative substrate bias, the growth started from surface pit formation, leading to self-aligned cone shaped ZnOx QDs with composition, x, being linearly dependent on substrate bias, providing an ideal platform for defect engineering and related application. Intriguingly, if there is no substrate bias applied, the most energetically favorable ZnOx hexagonal pyramids were formed on the surface, in quasi-epitaxy with the Si substrate. Spherical stoichimetric ZnO QDs in a narrow size range were synthesized when oxygen was particularly introduced, and these exhibited true quantum confinement effects, evidenced by a blue shift of the UV emission in the photoluminescence spectrum. This work facilitates the development of controllable ZnO QDs, and, mos...

Al-rich III–nitride-based deep-ultraviolet (UV) (275–320 nm) light-emitting diodes are plagued with a low emission efficiency and high turn-on voltages. We report Al-rich (Al,Ga)N metal–insulator–semiconductor UV light-emitting Schottky diodes with low turn-on voltages of

Nitride films are promising for advanced optoelectronic and electronic device applications. However, some challenges continue to impede development of high aluminum-containing devices. The two major difficulties are growth of high crystalline quality films with aluminum-rich compositions, and efficiently doping such films p-type. These problems have severely limited use of aluminum-rich nitride films grown by molecular beam epitaxy. A way around these problems is through use of a liquid-metal-enabled approach to molecular beam epitaxy. Although the presence of a liquid metal layer at the growth front is reminiscent of conventional liquid phase epitaxy, this approach is different in its details. Conventional liquid epitaxy is a near-thermodynamic equilibrium process which liquid-metal assisted molecular beam epitaxy is not. Growth of aluminum-rich nitrides is primarily driven by the kinetics of the molecular vapor fluxes, and the surface diffusion of adatoms through a liquid metal layer before incorporation. This paper reports on growth of high crystalline quality and highly doped aluminum-containing nitride films. Measured optical and electrical characterization data show that the approach is viable for growth of atomically smooth aluminum-containing nitride heterostructures. Extremely high p-type doping of up to $6 \times 10$$^{17}$ cm$^{-3}$ and n-type doping of up to $1 \times 10$$^{20}$ cm$^{-3}$ in Al$_{0.7}$Ga$_{0.3}$N films was achieved. Use of these metal-rich conditions is expected to have a significant impact on high efficiency and high power optoelectronic and electronic devices that require both high crystalline quality and highly doped (Al,Ga)N films.

Monascus species have traditionally been used in Asian food, with rice as their fermentation substrate. Red mold rice (RMR) contains citrinin, a nephrotoxic agent capable of exerting oxidative stress and cellular apoptosis. We investigated the components in RMR that could minimize the adverse effects of citrinin. Combining chemical separations and bioactivity assays, we identified an antioxidative component called deferricoprogen (DFC) in the fermented rice of Monascus purpureus NTU 568. The DFC structure was confirmed by nuclear magnetic resonance (NMR) and mass spectra analysis. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of DFC was similar to that of vitamin E. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and flow cytometric analysis showed the effect of DFC and citrinin on cell viability and cell cycle. DFC was found to be protective against the cytotoxicity and cell death induced by citrinin on human embryonic kidney (HEK-293) cells. DFC also demonstrated anti-apoptotic property in preventing citrinin-induced apoptosis.

An azaphilonidal derivative monaphilone A (MA) was recently isolated from the fermented products of Monascus purpureus NTU 568 by our laboratory. We report here the exploration of apoptosis-related and anti-inflammatory properties of MA and ankaflavin (AK) by some experiments about inducing death of human laryngeal carcinoma cell line HEp-2 and reducing inflammatory responses on murine macrophage RAW 264.7 cells. We employed a ssDNA enzyme-linked immunosorbent assay (ELISA) kit to investigate the nuclear changes of early apoptosis induced by AK and MA on HEp-2 cells and used a western blot and an enzyme activity assay to demonstrate the activation of caspase-3, caspase-8, and caspase-9 by MA and AK. Our studies revealed that AK and MA may decrease lipopolysaccharide (LPS)-induced inflammatory responses, including nitrite productions and expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in RAW 264.7 cells. All evidence support that azaphilonidal derivatives from M. purpureus NTU 568, such as AK and MA, are suitable for the development of chemotherapy or chemopreventive agents.

Nanowires are the building blocks of future nanodevices and thus methods for fabricating nanowires of various materials in various forms are fundamentally important. Although nanowires have been intensively studied, there are only a few methods that showed promising characteristics for practical applications. Here, we intend to review those patents, which enable nanowire growth to be more controllable and feasible for applications. Various methods for fabricating metal, semiconductor and organic nanowires with promising features are reviewed, where some emphasize the characteristics of individual nanowires, others address the uniformity and alignment of an array of nanowires as a whole. The patents for fabricating nanowires of various materials are introduced in the first part. In the second part, the patents to improve crystalline quality, morphology, uniformity of nanowires are introduced. Finally, the patents for growing aligned nanowire arrays and aligning dispersed nanowires are reviewed.

A new diterpene, 16-hydroxy communic acid (1), along with thirty one known compounds including five norditerpenes (2-6), twenty two flavonoids containing four biflavonoids (7-10), nine monoflavonoids (11-19) and nine flavanoid glycosides (20-28), as well as four phenolic constituents (29-32) were isolated from the 95% ethanolic extract of Podocarpus fasciculus. The structure of 1 was elucidated using spectral methods. Of these isolates, nagilactone C (2) showed the most significant inhibitory effects against DLD cells (human colon carcinoma) (ED(50)=2.57 microg/ml) and compounds 7, 8, 10, 11, and 12 had moderate cytotoxic activity against human KB (human oral epithelium carcinoma), Hela (human cervical carcinoma), Hepa (human hepatoma), DLD (colon carcinoma), and A-549 (human lung carcinoma) tumor cell lines. Preliminary structure-activity relationship studies of the isolated diterpenoids and biflavonoids are discussed.

A new diterpene, 16-hydroxy communic acid (1), along with thirty one known compounds including five norditerpenes (2-6), twenty two flavonoids containing four biflavonoids (7-10), nine monoflavonoids (11-19) and nine flavanoid glycosides (20-28), as well as four phenolic constituents (29-32) were isolated from the 95% ethanolic extract of Podocarpus fasciculus. The structure of 1 was elucidated using spectral methods. Of these isolates, nagilactone C (2) showed the most significant inhibitory effects against DLD cells (human colon carcinoma) (ED(50)=2.57 microg/ml) and compounds 7, 8, 10, 11, and 12 had moderate cytotoxic activity against human KB (human oral epithelium carcinoma), Hela (human cervical carcinoma), Hepa (human hepatoma), DLD (colon carcinoma), and A-549 (human lung carcinoma) tumor cell lines. Preliminary structure-activity relationship studies of the isolated diterpenoids and biflavonoids are discussed.

Summary form given only. ZnO possesses superior semiconductor properties and chemical stability and thus has attracted much attention for potential applications in piezoelectric and optoelectronic devices. With the trend toward nanoscale object fabrication for better carrier confinement, research on ZnO quantum dots becomes more active. Up to now, high quality ZnO quantum dots have only been demonstrated by pulsed laser deposition (PLD) assisted with anodic aluminum oxide templates [i], metal-organic chemical vapor deposition (MOCVD) [ii,iii] or molecular beam epitaxy (MBE) [iv , v]. While some of the processes were complicate, all of them require delicate design and controls. Thus, we attempt to provide an easier method to fabricate high crystalline ZnO nanodots by RF magnetron sputter. We demonstrated that self-assembled Zn or ZnO nanodots could be fabricated only by oblique-angle RF magnetron sputter on a rotating Si substrate at 470degC where the sputtering gas is Ar and hydrogen and the target is pure ZnO. When a large substrate bias of -400 V was applied, the resulting dots are pure Zn. Scanning electron microscopy (SEM) results show that the nanodots grown on Si (100) substrate for the growth time of 30 min and 60 min are semispherical shape as shown in Fig.l, with the average dot size of 30 nm and 50 nm and the dot density of 3 x 1010/cm2 and 1.8 x 1010/cm2, respectively. However, the nanodots are composed of Zn rather than ZnO, determined by scanning transmission electron microscopy (STEM) analysis as shown in Fig.2. High-resolution transmission electron microscopy (TEM) results in Fig.3 show that the as-prepared Zn nanodots are of single crystalline. The dots nucleated from surface pits resulting from ion bombardment during sputtering, and the side walls of the nanodots appear to be Si (111) facets. The as-synthesized rectangular nanodots seem to be well aligned with silicon substrate from the plan-view TEM bright-field image (Fig. 4 (a) and (b)), with Zn // Si . When no substrate bias was applied, hexagonal pyramidal ZnO dots result faceted with as shown in Fig. 5. The composition is confirmed by STEM energy dispersive spectroscopy (EDS) and the pyramidal dots emitted a UV light at 385 nm"1 from cathodeluminescence measurements. Compared with others, this novel method could provide advantages on higher uniformity, low cost, and more controls, which renders this to be useful for industrial applications in many optoelectronic devices.