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A new neutral particle analyzer (NPA) diagnostic based on single crystal chemical vapor deposition (sCVD) diamond detector that provides measurements of fast ions has been designed and installed on HL-2A tokamak. Diamond detectors have been applied in some magnetic confinement fusion devices due to their outstanding properties of compact size and radiation hardness. This DNPA can measure energies above 13.4 keV. The line of sight (LOS) of the DNPA intersects with the NBI No. 2 with a tangency radius of 154.8 cm. Due to the pitch angle defined by the LOS and geometry of the diagnostic, the DNPA is mainly sensitive to trapped ions. To interpret the energy spectrum and verify the feasibility of the design of the DNPA, a Monte Carlo code called FIDASIM, which is a synthetic diagnostic code that simulates fast ion D-alpha and NPA signals, is applied to model the neutral flux reaching the detector. The results show that the flux is mainly contributed by the low energy fast ions (E < 10 keV) and it is mainly coming from the active components, the passive signal is dominant in the high energy region (E > 15 keV). The modeling features the ability to distinguish between active and passive signals, and the simulated strong passive signals are suggested to come from charge exchange between cold neutrals and fast ions around the plasma edge. In addition, despite the large ratio of halo neutrals, essentially it has a limited contribution to the energy spectrum. [ABSTRACT FROM AUTHOR]

Complex interaction between emissions, meteorology and atmospheric chemistry makes accurate predictions of particulate pollution difficult. Advanced data mining techniques can dig out potential laws from massive data, providing new possibilities for understanding the evolution and causes of particulate pollution. Based on the Granger method and block modeling analysis, this study explored the spillover effects of hourly PM2.5 to determine the specific role (i.e., overflow, bilateral, inflow and limited inflow) of each city in Hubei, China. The results suggest that the northern and central cities with high level PM concentration in Hubei have a significant spillover effect, while the eastern and southern cities generally play a role as the sink of pollutant. [ABSTRACT FROM AUTHOR]

The hydrogen/deuterium (H/D) isotope effect on a zonal flow and its configuration dependence are experimentally studied in a helical device, Heliotron J. The isotope dependence of a toroidally symmetric potential fluctuation in the frequency range of <∼4 kHz, a zonal flow, is observed in low-density electron cyclotron resonance heated plasmas in Heliotron J. In the standard configuration, the zonal flow interacting with turbulence is enhanced as the D gas fraction increases. The zonal flow is more dominated against turbulent fluctuation in D plasmas, which should have a favourable impact on turbulence transport. Interestingly, however, the opposite dependence of the zonal flow activity on the isotope ratio is also observed in the different magnetic configurations. The configuration dependence observed in this experiment could be one of the factors to explain the difference in the isotope effect of confinement improvement between tokamaks and helical devices. Impurities and radial electric field, which can also be influenced by isotope mass through the difference in neoclassical transport and plasma-wall interaction, have insignificant influences on the zonal flow behaviour in this experiment. [ABSTRACT FROM AUTHOR]

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/ [ABSTRACT FROM AUTHOR]

A new bimetallic coordination polymer [In2Na(H2O)2(ddca)3](NO3)·4H2O (1, H2ddca = 6,6′-dithiodinicotinic acid) is produced via a hydrothermal reaction of In(NO3)3, H2ddca with NaOH as the pH modulator. Various characterization methods, such as thermogravimetric analysis (TGA), elemental analysis (EA), single crystal and powder X-ray diffraction measurements, are used. Furthermore, a process of sonochemistry with oleic acid at 453 K is used to produce nanoparticles of 1 (nano-1). In terms of the biological function of the synthesized complex, the real-time reverse transcription-polymerase chain reaction is carried out to explore the relative mRNA expression of miR-181 in MGC-803, BGC-823, and SGC-7901 gastric cancer cell lines, and the western blot is used to explore the protein expression of apoptotic protein Bcl-2. [ABSTRACT FROM AUTHOR]

Bearings, as a key part of a vehicle transmission system, were extensively studied to improve their abrasion resistance and fatigue life. Mixtures of hard ceramic particles, namely, molybdenum disulphide (MoS2) and graphite particles (PC), were sprayed with a high-pressure inert gas onto the surface of AISI52100 bearing steel, forming the lubricant film. The morphology and phase composition of the protective layer were examined using confocal laser scanning microscopy, surface roughness tester, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The changes in surface microhardness were evaluated with a microhardness tester. The friction factor and anti-wear properties of the lubricant layer were assessed with an SRV-IV microvibration tester. The solid lubricant is shown to effectively reduce the friction factor. The surface modification gave a twofold increase in extreme pressure 14% reduction in the friction factor, and 20% enhancement in microhardness. This study offers a practical method to enhance the bearing surface strength for a vehicle transmission system. [ABSTRACT FROM AUTHOR]

We have performed micromagnetic simulations to investigate the magnetic behavior of exchange spring grains for hard disk recording applications. The thickness ratio between magnetically hard and soft layers was varied while the soft layer anisotropy was altered to maintain a suitable energy barrier between opposite magnetization states. The minimum required magnetic field for switching a grain and the corresponding field angle were both significantly reduced in exchange spring material compared with single-phase grains. This could lead to reduced cross-track write errors in hard drive systems and assist the development of magnetic multilayer recording technologies. [ABSTRACT FROM AUTHOR]

Sugar nucleotides, the activated forms of monosaccharides, are used as donor substrates by glycosyltransferases in the in vivo biosynthesis of polysaccharides, proteoglycans and glycoglycerolipids. In mammals, uridine 5'-diphosphate-glucose (UDP-Glc) and uridine 5'-diphosphate-glucuronic acid (UDP-GlcA) are common building blocks of glycans and glycoconjugates. The commercial demand for these high-energy donors is increasing, while the understanding and application of enzymatic glycan synthesis has leapt forward in recent years. To produce valuable UDP-GlcA in a cost-effective way, here, UDP-sugar pyrophosphorylase from Arabidopsis thaliana was constitutively expressed in Pichia pastoris and secreted into the extracellular medium. Under these conditions, the synthesis of 4.2 g UDP-GlcA or 5.5 g UDP-Glc per liter of culture was revealed in the culture medium, without any need for purification. An anion exchange chromatography purification method for UDP-sugars was also developed. This route opens a door to large-scale production of the cheaper UDP-GlcA. [ABSTRACT FROM AUTHOR]

Aim Extralevator abdominoperineal excision (ELAPR) is challenging 'conventional' abdominoperineal excision (APR), yet the safety and efficacy of ELAPR is still under debate. We therefore developed a laparoscopic APR with trans-abdominal individualized levator transection (LAPR-TILT) approach and compared the outcome with a conventional laparoscopic APR (CLAPR). Method All eligible patients were entered a single-centre randomized controlled trial to compare CLAPR and LAPR-TILT. We assessed the first 185 patients, including operative findings, complications, histopathology and urogenital function. Results Ninety-three patients in the CLAPR group and 92 patients in the APR-TILT group were included for analysis. The APR-TILT procedure took less time [137 (101-175) min vs 146 (102-187) min; P = 0.03], mainly owing to faster perineal dissection. APR-TILT resulted in a reduced rate of bowel perforation (1.1% vs 8.6%; P = 0.04), circumferential resection margin positivity (1.1% vs 10.8%; P = 0.01) and postoperative wound complications (5.4% vs 16.2%; P = 0.02) compared with the CLAPR procedure. At a median follow-up of 19 months after surgery, three patients (3.2%) in the CLAPR group had tumour recurrence while no tumour recurrence occurred in the LAPR-TILT group. Patients who underwent LAPR-TILT reported fewer urinary or sexual problems (LAPR-TILT vs CLAPR, 10.9% vs 24.7% and 17.4% vs 38.7%, respectively). Conclusion Compared with CLAPR, LAPR-TILT achieved better pathological results for factors that are surrogate parameters for local recurrence. LAPR-TILT could also reduce the risk of urogenital dysfunction. [ABSTRACT FROM AUTHOR]

On HL-2A tokamak, supersonic molecular beam injection (SMBI) has been developed as a routine refueling method. The key components of the system are an electromagnetic valve and a conic nozzle. The valve and conic nozzle are assembled to compose the simplified Laval nozzle for generating the pulsed beam. The appurtenance of the system includes the cooling system serving the cooled SMBI generation and the in situ calibration component for quantitative injection. Compared with the conventional gas puffing, the SMBI features prompt response and larger fueling flux. These merits devote the SMBI a good fueling method, an excellent plasma density feedback control tool, and an edge localized mode mitigation resource. [ABSTRACT FROM AUTHOR]

Aims To compare the efficacy and safety of liraglutide versus sitagliptin as add-on to metformin after 26 weeks of treatment in Chinese patients with type 2 diabetes mellitus ( T2DM). Methods This 26-week open-label, active comparator trial ( NCT02008682) randomized patients (aged 18-80 years) with T2DM inadequately controlled with metformin [glycated haemoglobin ( HbA1c) 7.0-10.0% (53-86 mmol/mol)] 1 : 1 to once-daily subcutaneously administered liraglutide 1.8 mg (n = 184) or once-daily oral sitagliptin 100 mg (n = 184), both as add-on to metformin. The primary endpoint was change in HbA1c from baseline to week 26. Results Liraglutide was superior to sitagliptin in reducing HbA1c from baseline [8.1% (65 mmol/mol)] to 26 weeks, as evidenced by estimated mean HbA1c change of −1.65% (−18.07 mmol/mol) versus −0.98% (−10.72 mmol/mol), respectively [estimated treatment difference for liraglutide vs sitagliptin of −0.67% (95% CI −0.86, −0.48) or −7.35 mmol/mol (95% CI −9.43; −5.26); p < 0.0001]. More patients receiving liraglutide (76.5%) than sitagliptin (52.6%) achieved the HbA1c target of <7.0% (53 mmol/mol) at week 26 [odds ratio 3.65 (95% CI 2.18, 6.12); p < 0.0001]. Reductions in fasting plasma glucose, 7-point self-measured plasma glucose and body weight were greater with liraglutide than with sitagliptin (p < 0.0001 for all). More patients experienced nausea (14.8% vs 0.5%), diarrhoea (8.2% vs 2.2%) and decreased appetite (10.9% vs 0.5%) with liraglutide than sitagliptin. Two hypoglycaemic episodes were confirmed for liraglutide and one for sitagliptin; none were severe or nocturnal. Conclusions Liraglutide provided better glycaemic control and greater body weight reduction than sitagliptin when administered as add-on to metformin. More patients had nausea, diarrhoea and decreased appetite with liraglutide versus sitagliptin. [ABSTRACT FROM AUTHOR]

A new molybdenum(VI) complex, [MoO(CHOH)(L)] (L = N′-(4-diethylamino-2-hydroxybenzylidene)-4-hydroxybenzohydrazide), was prepared and characterized by spectroscopy methods and single crystal X-ray diffraction (CIF file CCDC no. 1038153). The crystal of the complex, CHMoNO, crystallizes in the triclinic space group $$P\bar 1$$ with unit cell dimensions a = 6.9824(9), b = 10.206(1), c = 15.302(2) Å, α = 94.399(2)°, β = 101.877(2)°, γ = 104.062(2)°, V = 1025.9(2) Å, Z = 2, R = 0.0317, wR = 0.0796, S = 1.060. The Mo atom in the complex is in an octahedral coordination with phenolate O, imino N, enolate O atoms of the ligand L, and one oxo O in the equatorial plane, and with one methanol O and the other oxo O in the axial sites. Crystals of the complex are stabilized by hydrogen bonds. The complex was studied for its catalytic oxidation property on some olefins, with tert-butyl hydrogen peroxide as oxidant. [ABSTRACT FROM AUTHOR]

A fluctuation analysis technique using analytic signals is proposed. Analytic signals are suitable to characterize a single mode with time-dependent amplitude and frequency, such as an MHD mode observed in fusion plasmas since the technique can evaluate amplitude and frequency at a specific moment without limitations of temporal and frequency resolutions, which is problematic in Fourier-based analyses. Moreover, a concept of instantaneous phase difference is newly introduced, and error of the evaluated phase difference and its error reduction techniques using conditional/ensemble averaging are discussed. These techniques are applied to experimental data of the beam emission spectroscopic measurement in the Heliotron J device, which demonstrates that the technique can describe nonlinear evolution of MHD instabilities. This technique is widely applicable to other diagnostics having necessity to evaluate phase difference. [ABSTRACT FROM AUTHOR]

Interferon γ (IFN-γ), an anticancer agent, is a strong inducer of indoleamine 2,3-dioxygenase 1 (IDO1), which is a tryptophan-metabolizing enzyme involved in the induction of tumor immune tolerance. In this study, we investigated the IDO1 expression in organs after IFN-γ gene transfer to mice. IFN-γ gene transfer greatly increased the mRNA expression of IDO1 in many tissues with the highest in the liver. This upregulation was associated with reduced L-tryptophan levels and increased L-kynurenine levels in serum, indicating that IFN-γ gene transfer increased the IDO activity. Then, Lewis lung carcinoma (LLC) tumor-bearing wild-type and IDO1-knockout (IDO1 KO) mice were used to investigate the effects of IDO1 on the antitumor activity of IFN-γ. IFN-γ gene transfer significantly retarded the tumor growth in both strains without any significant difference in tumor size between the two groups. By contrast, the IDO1 activity was increased only in the wild-type mice by IFN-γ gene transfer, suggesting that cells other than LLC cells, such as tumor stromal cells, are the major contributors of IDO1 expression in LLC tumor. Taken together, these results imply that IFN-γ gene transfer mediated IDO1 upregulation in cells other than LLC cells has hardly any effect on the antitumor activity of IFN-γ. [ABSTRACT FROM AUTHOR]

Two new complexes [Zn(Hpda)(Bth-6)] ( I) and [Zn(Hpda)] · 2(H-Bpe) ( II) (HpdaH = 4-hydroxypyridine-2,6-dicarboxylic acid, Bth-6 = 1,6-bis(1,2,4-triazol-1-yl)hexane, Bpe = 1,2-bi(4-pyridyl)ethene) have been synthesized and characterized structurally. Their X-ray crystal structures show that the two complexes belong to a monoclinic system; space group P2/ n with a = 11.9328(12), b = 20.975(2), c = 17.1544(17) Å; β = 91.406(2)°, Z = 4 for I; space group P2/ c with a = 12.7150(19), b = 14.000(2), c = 22.171(3) Å; β = 96.481(2)°, Z = 4 for II. Compound I possesses a one-dimensional (1D) zigzag chain structure, each zinc(II) ion is five-coordinated with a distorted triangle bipyramid geometry. Compound II is discrete mononuclear species, in which the zinc(II) ion is six-coordinated with a distorted octahedral geometry. The [Zn(Hpda)] units are connected one-dimensional chain by the intermolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

A novel reconstruction method is developed for acquiring the electron density profile from multichannel interferometric measurements of strongly asymmetrical toroidal plasmas. It is based on a regularization technique, and a generalized cross-validation function is used to optimize the regular-ization parameter with the aid of singular value decomposition. The feasibility of method could be testified by simulated measurements based on a magnetic configuration of the flexible helical-axis heliotron device, Heliotron J, which has an asymmetrical poloidal cross section. And the successful reconstruction makes possible to construct a multi-channel Far-infrared laser interferometry on this device. The advantages of this method are demonstrated by comparison with a conventional method. The factors which may affect the accuracy of the results are investigated, and an error analysis is carried out. Based on the obtained results, the proposed method is highly promising for accurately reconstructing the electron density in the asymmetrical toroidal plasma. [ABSTRACT FROM AUTHOR]

Edge fluctuation in a supersonic molecular-beam injection (SMBI) fueled plasma has been measured using an electrostatic probe array. After SMBI, the plasma stored energy (Wp) temporarily decreased then started to increase. The local plasma fluctuation and fluctuation induced particle transport before and after SMBI have been analyzed. In a short duration (4 ms) just after SMBI, the density fluctuation of broad-band low frequency increased, and the probability density function (PDF) changed from a nearly Gaussian to a positively skewed non-Gaussian one. This suggests that intermittent structures were produced due to SMBI. Also the fluctuation induced particle transport was greatly enhanced during this short duration. About 4ms after SMBI, the low frequency broad-band density fluctuation decreased, and the PDF returned to a nearly Gaussian shape. Also the fluctuation induced particle transport was reduced. Compared with conventional gas puff, Wp degradation window is very short due to the short injection period of SMBI. After this short degradation window, fluctuation induced particle transport was reduced and Wp started the climbing phase. Therefore, the short period of the influence to the edge fluctuation might be an advantage of this novel fueling technique. On the other hand, although their roles are not identified at present, coherent MHD modes are also suppressed as well by the application of SMBI. These MHD modes are thought to be de-exited due to a sudden change of the edge density and/or excitation conditions. [ABSTRACT FROM AUTHOR]

The article focuses on a study to examine the nonlinear vibration behavior of symmetrically placed and axially immovable spring-hinged beams. According to the study, harmonic imbalance and galerkin methods have been used to evaluate analytical approximate solutions in closed and explicit form. The study also predicts that analytical approximate solutions are directly validated by comparing with the results of finite element methods.

Second harmonic electron cyclotron current drive (ECCD) has been applied in the stellarator/heliotron (S/H) device, Heliotron J, to stabilize magnetohydrodynamic (MHD) modes. The energetic particle mode (EPM) of 60–90 kHz frequency, one of the energetic-ion-driven MHD modes, is excited in a plasma heated by co- and counter-neutral beam injection and electron cyclotron heating (ECH). The EPM has been stabilized by counter-ECCD which decreases the rotational transform. Localized EC current driven by a few kA at the central region modifies the rotational transform profile, ι/2π, leading to the formation of a high magnetic shear at the radius where the mode is excited. An experiment scanning the EC-driven current shows that there is a threshold in magnetic shear and/or rotational transform to stabilize the EPM. [ABSTRACT FROM AUTHOR]

Encarsia sophia (Girault and Dodd) is an autoparasitoid in the hymenopteran family Aphelinidae. The females develop as primary parasitoids on whitefly nymphs (primary hosts), whereas the males develop as hyperparasitoids on their own species or on other primary parasitoid species (secondary hosts). The autoparasitoids not only parasitise whiteflies but also kill them with strong host-feeding capacity. In this study, female and male E. sophia were reared on the primary hosts Trialeurodes vaporariorum and Bemisia tabaci 'Q', and the host-feeding and parasitism of wasps on both whitefly species were determined for the four possible different mating combinations: (i) E. sophia females reared on B. tabaci (ESF-BT) mated with E. sophia males from B. tabaci (ESM-BT), (ii) E. sophia females reared on T. vaporariorum (ESF-TV) mated with E. sophia males from T. vaporariorum (ESM-TV), (iii) ESF-BT mated with ESM-TV, and (iv) ESF-TV mated with ESM-BT. ESF-TV mated with ESM-TV killed the largest percentage of whitefly nymphs through host feeding. The ESF-TV with larger body size mating with larger ESM-TV killed more whitefly nymphs through host feeding than those mating with smaller ESM-BT. Whether B. tabaci or T. vaporariorum were used as hosts, ESF-TV mated with ESM-TV and ESM-BT and ESF-BT mated with ESM-BT significantly parasitised more whitefly nymphs than ESF-BT mated with ESM-TV. In general, ESF-BT mated with ESM-TV killed significantly fewer whitefly nymphs through parasitism and host feeding than the other three mating combinations on both whitefly species. These results indicated that the performance of autoparasitoids on insect pests was not only dependent on females but was also affected by mating with males from different primary host species. [ABSTRACT FROM AUTHOR]

Leukemia related protein 16 (LRP16) was first cloned from acute myeloid leukemia cells in our laboratory. In the present study, we sought to investigate the role of LRP16 in insulin action and sensitivity, using LRP16-depleted and -overexpressing 3T3-L1 cells. LRP16 silencing resulted in a reduction of the expression and secretion of tumor necrosis factor-alpha (TNF-α) and a concomitant increase in the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ). Moreover, LRP16 depletion promoted insulin-induced glucose uptake and adipocyte differentiation of 3T3-L1 cells. In contrast, LRP16 overexpression increased TNF-α secretion, suppressed glucose uptake, and attenuated 3T3-L1 cell differentiation. The phosphorylation levels of insulin receptor substrate 1 (IRS-1), phosphatidylinositide 3-kinase (PI3-K), and Akt were increased in LRP16-deficient 3T3-L1 cells, and conversely, diminished in LRP16-overexpressing 3T3-L1 cells, when compared to the corresponding control cells. Additionally, LRP16 overexpression raised the phosphorylation level of mammalian target of rapamycin (mTOR). The pretreatment with rapamycin, a specific inhibitor of mTOR, prevented the TNF-α elevation and PPAR-γ reduction and restored the phosphorylation of IRS-1, PI3-K, and Akt in LRP16- overexpressing cells. Our data collectively indicate that LRP16 acts as a negative regulator of insulin action and adipogenesis in 3T3-L1 adipocytes, which involves the activation of the mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Sustained expression of murine interferon (IFN)-γ (Muγ) was found to be effective in preventing tumor metastasis and atopic dermatitis in mouse models. However, our preliminary experiments suggested that the time-dependent decrease in the Muγ expression was not compensated for by repeated injections of Muγ-expressing plasmid. To identify the mechanism underlying this observation, a reporter plasmid was hydrodynamically injected into mice and the levels of the plasmid, mRNA and reporter protein were measured in mice receiving a pre- or co-administration of Muγ-expressing plasmid. Co-injection of Muγ-expressing plasmid had no significant effects on transgene expression from the reporter plasmid. In contrast, pre-injection of Muγ-expressing plasmid greatly inhibited the expression of the reporter protein. Moreover, pre-injection of Muγ-expressing plasmid also reduced the amount of the reporter plasmid in the nuclear fraction of mouse liver to <10%, and that of reporter mRNA to <1%. The degree of reduction in the expression of reporter protein was comparable with the reduction in mRNA. These results indicate that the difficulty in regaining the expression level of IFN-γ is due to the impaired delivery of plasmid to the nucleus and to the suppression of transcription from the plasmid. [ABSTRACT FROM AUTHOR]

Myostatin plays a pivotal role in controlling skeletal muscle mass in mammals. Polymorphisms in its promoter region likely impact on transcription and production traits. In this study, haplotypes involving three polymorphic sites in the promoter region of the porcine myostatin gene, namely at sites 435, 447 and 879, were identified and their effect on production traits, gene expression as well as on skeletal muscle traits were analysed. Four haplotypes were revealed and the linkage disequilibrium and evolutionary relationship were assessed. The results revealed that haplotypes A, B and C are predominant in Yorkshire and Landrace, Duroc and two Chinese indigenous pig breeds (Laiwu and Dapulian) respectively. The genotypes are associated with body weight on day 21 (BW21), average daily gain from birth to day 21 (ADG1) and average daily gain from day 21 to day 70 (ADG2) ( P < 0.05) in Duroc pigs. The activity of haplotype A (pGL3-A) is significantly higher than other constructs in driving reporter gene transcription ( P < 0.01). As compared with CC animals, the myostatin mRNA level in BC animals is relatively lower in both semimembranosus (SM) and semitendinosus (ST) skeletal muscles, and the difference was significant in the SM muscle ( P < 0.01). Moreover, the mRNA levels of MyHCI, MyHCIIa, MyHCIIb and MyHCIIx and the muscle fibre diameter and density were also compared between BC and CC animals. [ABSTRACT FROM AUTHOR]

Nanoparticles of lead sulfide (PbS) have been prepared by a surfactant micelle template-inducing reaction. These nanoparticles were dispersed in ethanol and investigated for their nonlinear optical properties by nanosecond laser pulses. Broadband optical limiting effects have been observed at the wavelengths of 355, 1064, and 430 nm and every 30 nm from 470 to 620 nm. The nonlinear light-scattering process in the suspensions of PbS nanoparticles was characterized at the wavelength of 532 nm. Nonlinear absorption and nonlinear scattering were deduced to be the mechanisms for the broadband optical limiting performance. The origins of the nonlinear scattering were discussed. [ABSTRACT FROM AUTHOR]

Nanoparticles of lead sulfide (PbS) have been prepared by a surfactant micelle template-inducing reaction. These nanoparticles were dispersed in ethanol and investigated for their nonlinear optical properties by nanosecond laser pulses. Broadband optical limiting effects have been observed at the wavelengths of 355, 1064, and 430 nm and every 30 nm from 470 to 620 nm. The nonlinear light-scattering process in the suspensions of PbS nanoparticles was characterized at the wavelength of 532 nm. Nonlinear absorption and nonlinear scattering were deduced to be the mechanisms for the broadband optical limiting performance. The origins of the nonlinear scattering were discussed. [ABSTRACT FROM AUTHOR]

Abstract. Thin heteroepitaxial films of Si[sub 1-x-y]Ge[sub x]C[sub y] have been grown on Si(100) substrates by rapid thermal chemical vapor deposition (RTCVD) using C[sub 2]H[sub 4] as C source. The composition and microstructure of Si[sub 1-x-y]Ge[sub x]C[sub y] films were characterized by Auger electron spectroscopy, Raman spectra and Fourier-transform infrared spectroscopy. The results show that lower temperature and higher SiH[sub 4]/C[sub 2]H[sub 4] flow ratio are helpful in forming the substitutional C and improving the crystal quality. A possible mechanism for C incorporation in Si[sub 1-x-y]Ge[sub x]C[sub y] layers grown by RTCVD using C[sub 2]H[sub 4] is proposed. [ABSTRACT FROM AUTHOR]

Abstract. The transient photoconductivity (PC) properties of GaN thin film on (0001) sapphire substrate are investigated. The decay curves of PC obtained by YAG:Nd pulsed laser are divided into two special regions, which are the beginning and tail decay regions, corresponding to two time constants, 0.1 ms and 1.0 ms, respectively. Keeping the same light intensity and bias voltage, when the sample is heated to 300 Celsius, the time constants are both reduced. It shows that there are a large number of traps at the position of tens of meV below the conduction band edge. The PC ascends S-shaped when the data are collected during the first 200 ns. As the sample is not illuminated, the PC sharply reduces and oscillates, indicating that the carriers redistribute between the deep traps and the conduction band. As an approximation, a model involving two trapping levels, the shallow and the deep trapping levels represents the structure of the electron trapping levels in the gap. The simulation based on this model is well in accordance with the experimental results. Moreover, the mechanism of how the PC curves varied as the light intensity is explained by the model. [ABSTRACT FROM AUTHOR]

Triplet state sublevel spectroscopy using optical detection of magnetic resonance (ODMR) in zero magnetic field can be successfully employed to study (i) the environment of tryptophan (Trp) residues in a protein by observing the position and structure of phosphorescence spectra, zero field ODMR transitions and triplet state sublevel kinetics, (ii) the energy transfer among Trp residues, and (iii) whether any cysteine (Cys) residue is within van der Waals distance of any Trp residue by studying the complex of the protein with methylmercury(II) iodide (CHHgI) which binds to Cys residues. These studies are particularly important where crystal structure study is not possible. Study of the S state often gives ambiguous results since fluorescence is always broad and shows multi-exponential decay. Our results on bacteriophage lysozyme T4 which contains three Trp residues at positions 126, 138 and 158 are presented. Measurements were facilitated by the use of a mutated enzyme containing one or two Trp-Tyr substitutions. The results indicate that (i) Trp 126 and 158 are solvent exposed, whereas Trp 138 is buried in a hydrophobic environment, (ii) S ↔ S non-radiative energy transfer takes place predominantly from Trp 126 to Trp 158, and (iii) only Trp-158 undergoes a heavy atom perturbation, which affects selectively the z-sublevel (z is an out-of-plane axis of the indole plane) as a result of CHHgI binding to nearby Cys 97. We suggest that the Hg atom is located on the z-axis of Trp 158 in the complex. This interpretation is based on our investigations on the effect of orientation of heavy atom perturbers in some naphthalene-crown ether metal ion complexes. [ABSTRACT FROM AUTHOR]

A Nd:YAG Thomson scattering system has been developed for Heliotron J. The system consists of two 550 mJ 50 Hz lasers, large collection optics, and 25 radial channel (~1 cm spatial resolution) interference polychromators. This measurement system achieves a S/N ratio of ~50 for low-density plasma (ne 0.5 x 1019 m-3). A time evolution of electron temperature profiles was measured with this system for a high-intensity gas-puff (HIGP) fueling neutral-beam-injection plasma. The peripheral temperature of the higher-density phase after HIGP recovers to the low-density pre-HIGP level, suggesting that improving particle transport in the HIGP plasma may be possible. [ABSTRACT FROM AUTHOR]

Abstract. Ge-rich Ge[sub 1-x-y]Si[sub x]C[sub y] alloys have been grown on Si (100) substrates by plasma-enhanced rapid thermal chemical vapor deposition. It is found that there is a strong suppressive effect of C on the Ge composition and the growth rate. A possible mechanism for the suppressive effect is proposed. After calculations of atomic configuration, we obtain the relationship between the degree of suppression and the Ge/C atomic ratio. From the calculation results, a saturation tendency of the suppressive effect is expected with increasing Ge concentration in the growth of Ge[sub l-x-y]Si[sub x]C[sub y] alloys. [ABSTRACT FROM AUTHOR]

A one-step method for the synthesis of 1-acyloxygermatranes RC(O)OGe(OCH 2CH 2) 3N in the reaction of germanium dioxide with triethanolamine and a carboxylic acid was developed. 1-Acyloxygermatranes, including those containing biologically active acyloxy groups (R = 2-MeC 6H 4CH 2OCH 2, C 6H 5, 2-HOC 6H 4), were obtained with a 82–96.5% yield. [ABSTRACT FROM AUTHOR]

In the existing mobile ad-hoc network (MANET) literature the vast majority of simulation studies that investigate routing protocol performance use a simplistic radio channel model, based on a two-ray ground-reflected path, and ignore both fast and slow fading. Reported are results from the first phase of an investigation into the use of a more realistic channel model, which incorporates the slow (lognormal) fading typically found in both outdoor and indoor mobile radio channels. The significance of the results are that they show previous papers may have significantly underestimated the radio path loss, thereby overestimating the performance of particular routing protocols. [ABSTRACT FROM AUTHOR]