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Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a key enzyme in the glycolytic pathway that catalyzes the conversion of D-glyceraldehyde 3-phosphate to 1,3-diphosphoglycerate. Here, the full-length GAPDH type 1 from Escherichia coli (EcGAPDH1) was cloned and overexpressed, and the protein was purified. Biochemical analyses found that the optimum reaction temperature and pH of EcGAPDH1 were 55°C and 10.0, respectively. The protein has a certain amount of thermostability. Crystals of EcGAPDH1 were obtained using the sitting-drop vapor-diffusion technique and X-ray diffraction data were collected to 1.88 Å resolution. Characterization of the crystals showed that they belonged to space group P41212, with unit-cell parameters a = b = 89.651, c = 341.007 Å, α = β = γ = 90°. The structure of EcGAPDH1 contains four subunits, each of which includes an N-terminal NAD+-binding domain and a C-terminal catalytic domain. Analysis of the NAD+-bound form showed some differences between the structures of EcGAPDH1 and human GAPDH. As EcGAPDH1 shares 100% identity with GAPDH from Shigella sonnei, its structure may help in finding a drug for the treatment of shigellosis.

It is well known that phosphorylation of extracellular signal-regulated kinase (ERK) is involved in prothoracicotropic hormone (PTTH)-stimulated ecdysteroidogenesis in insect prothoracic glands (PGs). In the present study, we further investigated the downstream signaling pathways. Our results showed that PTTH stimulated p90 ribosomal S6 kinase (RSK) phosphorylation at Thr573 in Bombyx mori PGs both in vitro and in vivo. The in vitro PTTH stimulation was stage- and dose-dependent. The absence of Ca2+ reduced PTTH-stimulated RSK phosphorylation. Stimulation of RSK phosphorylation was also observed after treatment with either A23187 or thapsigargin. A phospholipase C (PLC) inhibitor, U73122, blocked PTTH-stimulated RSK phosphorylation. These results indicate the involvement of Ca2+ and PLC. Treatment with diphenylene iodonium (DPI), a mitochondrial oxidative phosphorylation inhibitor, blocked PTTH-regulated RSK phosphorylation, indicating its redox regulation. A mitogen-activated protein kinase (MAPK)/ERK kinase (MEK) inhibitor, U0126, but not a phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002, decreased PTTH-stimulated RSK phosphorylation, indicating that ERK is an upstream signaling. A protein kinase C (PKC) inhibitor, chelerythrine C, inhibited PTTH-stimulated RSK phosphorylation, and a PKC activator, phorbol 12-myristate acetate (PMA) stimulated RSK phosphorylation, indicating the involvement of PKC. BI-D1870, a specific RSK inhibitor, partly prevented PTTH-stimulated RSK phosphorylation and significantly inhibited PTTH-stimulated ecdysteroid secretion, indicating that PTTH-stimulated RSK phosphorylation is involved in ecdysteroidogenesis. Taken together, these data indicate that PTTH activates RSK phosphorylation which plays important roles in PTTH-stimulated ecdysteroidogenesis. This article is protected by copyright. All rights reserved.

Odorant binding proteins (OBPs) and chemosensory proteins (CSPs) play essential roles in insect chemosensory recognition. Here, we identified nine OBPs and nine CSPs from the Myzus persicae transcriptome and genome. Genomic structure analysis showed that the number and length of the introns are much higher, and this appears to be a unique feature of aphid OBP genes. Three M. persicae OBP genes (OBP3/7/8) as well as CSP1/4/6, CSP2/9 and CSP5/8 are tandem arrayed in the genome. Phylogenetic analyses of five different aphid species suggest that aphid OBPs and CSPs are conserved in single copy across all aphids (with occasional losses), indicating that each OBP and CSP class evolved from a single gene in the common ancestor of aphids without subsequent duplication. Motif pattern analysis revealed that aphid OBP and CSP motifs are highly conserved, and this could suggest the conserved functions of aphid OBPs and CSPs. Three OBPs (MperOBP6/7/10) are expressed antennae specifically, and five OBPs (MperOBP2/4/5/8/9) are expressed antennae enriched, consistent with their putative olfactory roles. M. persicae CSPs showed much broader expression profiles in nonsensory organs than OBPs. None of the nine MperCSPs were found to be antennae specific, but five of them (MperCSP1/2/4/5/6) showed higher expression levels in the legs than in other tissues. MperCSP10 mainly expressed in the antennae and legs. The broad and diverse expression patterns of M. persicae CSPs suggest their multifunctions in olfactory perception, development and other processes.

Summary Background Charts of size at birth are used to assess the postnatal growth of preterm babies on the assumption that extrauterine growth should mimic that in the uterus. Methods The INTERGROWTH-21 st Project assessed fetal, newborn, and postnatal growth in eight geographically defined populations, in which maternal health care and nutritional needs were met. From these populations, the Fetal Growth Longitudinal Study selected low-risk women starting antenatal care before 14 weeks' gestation and monitored fetal growth by ultrasonography. All preterm births from this cohort were eligible for the Preterm Postnatal Follow-up Study, which included standardised anthropometric measurements, feeding practices based on breastfeeding, and data on morbidity, treatments, and development. To construct the preterm postnatal growth standards, we selected all live singletons born between 26 and before 37 weeks' gestation without congenital malformations, fetal growth restriction, or severe postnatal morbidity. We did analyses with second-degree fractional polynomial regression models in a multilevel framework accounting for repeated measures. Fetal and neonatal data were pooled from study sites and stratified by postmenstrual age. For neonates, boys and girls were assessed separately. Findings From 4607 women enrolled in the study, there were 224 preterm singleton births, of which 201 (90%) were enrolled in the Preterm Postnatal Follow-up Study. Variance component analysis showed that only 0·2% and 4·0% of the total variability in postnatal length and head circumference, respectively, could be attributed to between-site differences, justifying pooling the data from all study sites. Preterm growth patterns differed from those for babies in the INTERGROWTH-21 st Newborn Size Standards. They overlapped with the WHO Child Growth Standards for term babies by 64 weeks' postmenstrual age. Interpretation Our data have yielded standards for postnatal growth in preterm infants. These standards should be used for the assessment of preterm infants until 64 weeks' postmenstrual age, after which the WHO Child Growth Standards are appropriate. Size-at-birth charts should not be used to measure postnatal growth of preterm infants. Funding Bill & Melinda Gates Foundation.

Aims This study aimed to investigate the potential of Bacillus methylotrophicus as a probiotic. Methods and Results A Bacillus isolate designated strain C14 was isolated from Korean traditional fermented soybean paste (doenjang). The strain was identified, and its physiological and biochemical properties were characterized. The gastrointestinal tolerance and immunomodulatory function of strain C14 were also investigated. Strain C14 was identified as B. methylotrophicus by analysis of its biochemical properties using the API 50CHB system and by phylogenetic analysis of the 16S rDNA sequence. Strain C14 showed >80% and >75% of survival for artificial gastric juices (pH 2·5 and 1% pepsin) and 0·5% (w/v) bile salt, respectively. Heat-killed B. methylotrophicus C14 inhibited the adhesion of various pathogens and enhanced the adhesion of probiotic bacteria to Caco-2 cells. The heat-killed cells also induced high levels of immune cell proliferation compared with the control and stimulated interleukin-6 and tumour necrosis factor-α production in mouse macrophages. Conclusions Bacillus methylotrophicus C14 could be used as a probiotic. Significance and Impact of the Study Recently identified B. methylotrophicus is a new potential probiotic with high gastrointestinal tolerance.

Odorant-binding proteins (OBPs) are crucial in the olfactory pathway of insects. In the present study, the antenna-enriched OBP AlinOBP13 was investigated because of its potential contribution to the peripheral olfactory perception in the alfalfa plant bug Adelphocoris lineolatus. The results of quantitative reverse transcriptase-PCR showed that the transcript level of AlinOBP13 was higher in the adult stage than in the nymph stages. The transcript levels of AlinOBP13 in the male and female antennae significantly increased after 4 and 8 h of starvation, respectively. Fine ultrastructures of different types of chemosensilla in both female and male antennae were investigated using transmission electron microscopy and immunocytochemical labelling. The results revealed that the anti-AlinOBP13 antiserum strongly and specifically labelled short basiconic sensilla; this antiserum was restricted to the inner lumen and the cavities below the sensillum base of the sensilla. By contrast, multiporous sensilla trichodea, medium long sensilla basiconica, and aporous sensilla chaetica were not labelled. The present study is the first to report an OBP showing specific expression in the short basiconic sensilla of a member of the Hemipteran species. The results of a fluorescence displacement binding assay indicated that recombinant AlinOBP13 showed a more specific binding preference to terpenoids than to sex pheromones and other classes of chemicals. This binding ability was dramatically affected by pH; higher binding affinities were displayed at pH 10.0 than at pH 7.4 and 5.0. In addition, the results of dose-dependent electroantennogram recordings from the antennae showed that both female and male adult bugs responded to the terpenoids tested, suggesting an apparent physiological relevance of AlinOBP13 in A. lineolatus chemoreception. The results of this study suggest that AlinOBP13 functions as a specific carrier of terpenoids and provide insights into the mechanism of A. lineolatus in response to green volatiles.

Olfaction plays an important role in insects' survival and reproduction. Odorant-binding proteins (OBPs) are considered to be one of the crucial proteins in the insect olfactory pathway. In this study, an antenna-specific OBP of the alfalfa plant bug, Adelphocoris lineolatus AlinOBP5, was expressed and purified in vitro. The binding affinities of AlinOBP5 with sex pheromone analogues of the Miridae and cotton volatiles were investigated by fluorescence competitive binding assays. The binding sites of AlinOBP5 were predicted by three-dimensional structure modelling and molecular docking, and site-directed mutagenesis. AlinOBP5 could not effectively bind with sex pheromone analogues of Miridae but showed high binding abilities with specific cotton volatiles, such as cis-nerolidol, ethyl laurate, β-ionone, β-caryophyllene, 2,3-dimethylbenzoic acid and (E)-farnesol. The strongest binding affinity was to cis-nerolidol, suggesting a role of AlinOBP5 in general odorant chemoreception. Based on the relatively strong binding affinity and the reported physiological activity of cis-nerolidol in other insects, we chose cis-nerolidol for further homology modelling and ligand docking. The results of molecular simulation and site-directed mutagenesis indicated that two amino acids, Lys74 and Pro121, in the protein binding pocket are the key amino acids involved in the binding of cis-nerolidol. The Lys74 residue may participate in specific recognition of ligands, and the Pro121 residue plays a crucial role in ligand binding and release by changing the binding pocket environment and stabilizing the conformation of the C-terminus of AlinOBP5.

To explore the main effects of weather factors on heat stroke.Data from case report on heat stroke was collected in Ningbo city during 2011 to 2014. Temperature threshold, lag effects and interaction of weather factors on heat stroke had been analyzed, using the piecewise regression model, distributed lag non-linear model, response surface model and other methods.RESULTS showed that temperature and humidity were more correlated with heat stroke than other weather-related factors. Through different models, daily average temperature always presented a better role in predicting the heat stroke, rather than maximum or minimum temperature. Positive association between daily average temperature and heat stroke was obvious, especially at lag 0-1 days, with its threshold as 29.1 (95% CI: 28.7-29.5) ℃ . The cumulative RR of heat stroke at 90(th) percentile of daily average temperature versus 10(th) percentile was 14.05 (95% CI: 7.23-27.31) in lag 0-1 days. The effects of daily relative humidity on heat stroke appeared nonlinear, with low humidity showing a negative effect on heat stroke and could lag for 1-4 days. However, the effect of high humidity was not significant, with the cumulative RR of low humidity and high humidity as 2.35 (95%CI: 1.27-4.33) and 0.86 (95%CI: 0.40-1.85) in lag of 0-4 days, respectively. We also noticed that there was an interactive effect of both temperature and humidity on heat stroke. Under high temperature and low humidity, the risk of heat stroke showed the highest.Temperature and humidity showed obvious relationship with heat stroke in Ningbo city, with the threshold temperature as 29.1 ℃. Under high temperature and low humidity, the risk of heat stroke became the highest.

To explore the short-term effect of particulate matters with an aerodynamic diameter of less than or equal to 10 μg (PM10) and aerodynamic diameter of less than or equal to 2.5 μg (PM2.5) on cardio-cerebrovascular mortality in Ningbo city.Daily cardio-cerebrovascular mortality data from 2011 to 2014 in Ningbo city were collected and the time series study using a semi-parametric generalized additive model were used to evaluate the relationship between the mortality of cardio-cerebrovascular disease and particulate matters after adjustment for the long-term trend of death,weather conditions, "days of the week" and other confounding factors.In single-pollutant model, the short-term effects of particulate matter on cardio-cerebrovascular mortality was strongest in lagged 2 days in Ningbo city, and an increase of 10 μg/m(3) in moving average concentrations (lagged 2-3 days and lagged 2-4 days) of PM2.5 and PM10 could increase the cardio-cerebrovascular mortality by 0.55% (0.23%-0.87%) and 0.53% (0.28%-0.78%), respectively. In multi-pollutant models, PM10 did remain robust after being adjusted for PM2.5 with 0.58% (0.09%-1.07%) increase in cardio-cerebrovascular mortality. The effect of PM2.5 had no statistical significantce after being adjusted for other co-pollutants.These findings suggested that the concentrations of ambient particulate matters were associated with an increased risk of daily cardio-cerebrovascular mortality in Ningbo city.

We present photometric observations of four transits in the WASP-17 planetary system, obtained using telescope defocussing techniques and with scatters reaching 0.5 mmag per point. Our revised orbital period is 4.0 +/- 0.6 s longer than previous measurements, a difference of 6.6 sigma, and does not support the published detections of orbital eccentricity in this system. We model the light curves using the JKTEBOP code and calculate the physical properties of the system by recourse to five sets of theoretical stellar model predictions. The resulting planetary radius, Rb = 1.932 +/- 0.052 +/- 0.010 Rjup (statistical and systematic errors respectively), provides confirmation that WASP-17b is the largest planet currently known. All fourteen planets with radii measured to be greater than 1.6 Rjup are found around comparatively hot (Teff > 5900 K) and massive (MA > 1.15 Msun) stars. Chromospheric activity indicators are available for eight of these stars, and all imply a low activity level. The planets have small or zero orbital eccentricities, so tidal effects struggle to explain their large radii. The observed dearth of large planets around small stars may be natural but could also be due to observational biases against deep transits, if these are mistakenly labelled as false positives and so not followed up.

Odorant-binding proteins (OBPs) are crucial in the olfactory pathway of insects. In the present study, the antenna-enriched OBP AlinOBP13 was investigated because of its potential contribution to the peripheral olfactory perception in the alfalfa plant bug Adelphocoris lineolatus. The results of quantitative reverse transcriptase-PCR showed that the transcript level of AlinOBP13 was higher in the adult stage than in the nymph stages. The transcript levels of AlinOBP13 in the male and female antennae significantly increased after 4 and 8 h of starvation, respectively. Fine ultrastructures of different types of chemosensilla in both female and male antennae were investigated using transmission electron microscopy and immunocytochemical labelling. The results revealed that the anti-AlinOBP13 antiserum strongly and specifically labelled short basiconic sensilla; this antiserum was restricted to the inner lumen and the cavities below the sensillum base of the sensilla. By contrast, multiporous sensilla trichodea, medium long sensilla basiconica, and aporous sensilla chaetica were not labelled. The present study is the first to report an OBP showing specific expression in the short basiconic sensilla of a member of the Hemipteran species. The results of a fluorescence displacement binding assay indicated that recombinant AlinOBP13 showed a more specific binding preference to terpenoids than to sex pheromones and other classes of chemicals. This binding ability was dramatically affected by pH; higher binding affinities were displayed at pH 10.0 than at pH 7.4 and 5.0. In addition, the results of dose-dependent electroantennogram recordings from the antennae showed that both female and male adult bugs responded to the terpenoids tested, suggesting an apparent physiological relevance of AlinOBP13 in A. lineolatus chemoreception. The results of this study suggest that AlinOBP13 functions as a specific carrier of terpenoids and provide insights into the mechanism of A. lineolatus in response to green volatiles.

The impact of device scaling on modern MOS technology is discussed in terms of the random telegraph signals (RTSs) and low-frequency noise in n-MOSFETs with gradually decreased channel widths. RTSs with very large amplitude (>60%) are observed in the devices with ultra-narrow channels at room temperature for the first time. Furthermore, low-frequency noise spectra having both 1/f′ and Lorentzian type are found separately in the same ultra-narrow channel at different gate bias voltage, whereas only 1/f′ noise is observed in relatively wide channels. The observations strongly suggest that low-frequency noise in weak inversion dominantly suffer from carrier mobility fluctuation rather than carrier number fluctuation in ultra-narrow channels, which is confirmed by numerical simulations.

The peroxisome proliferator-activated receptors (PPARs)-α, -β/δ, and -γ are the ligand-activated transcription factors that function as the master regulators of glucose, fatty acid and lipoprotein metabolism, inflammation, and atherosclerosis. Our aim was to test the association between ten single nucleotide polymorphisms of PPARs and CRP level, as well as their interaction with overweight/obesity. A sample population of 643 subjects was recruited from the prevention of MetS and multi-metabolic disorders in Jiangsu Province of China Study. The selected SNPs in PPAR α (rs135539, rs4253778, rs1800206), PPAR β/δ (rs2016520 and rs9794), and PPAR γ (rs10865710, rs1805192, rs709158, rs3856806, and rs4684847) were genotyped. After adjustment for smoking, alcohol consumption, SBP, DBP, TG, and HDL-C, rs1800206, rs709158, rs1805192, and rs4684847 polymorphisms were significantly associated with CRP level in normal weight subjects (P < 0.05). In the overweight/obese subjects, rs1800206 was also significant associated with CRP level (P

Olfaction plays an important role in insects' survival and reproduction. Odorant-binding proteins (OBPs) are considered to be one of the crucial proteins in the insect olfactory pathway. In this study, an antenna-specific OBP of the alfalfa plant bug, Adelphocoris lineolatus AlinOBP5, was expressed and purified in vitro. The binding affinities of AlinOBP5 with sex pheromone analogues of the Miridae and cotton volatiles were investigated by fluorescence competitive binding assays. The binding sites of AlinOBP5 were predicted by three-dimensional structure modelling and molecular docking, and site-directed mutagenesis. AlinOBP5 could not effectively bind with sex pheromone analogues of Miridae but showed high binding abilities with specific cotton volatiles, such as cis-nerolidol, ethyl laurate, β-ionone, β-caryophyllene, 2,3-dimethylbenzoic acid and (E)-farnesol. The strongest binding affinity was to cis-nerolidol, suggesting a role of AlinOBP5 in general odorant chemoreception. Based on the relatively strong binding affinity and the reported physiological activity of cis-nerolidol in other insects, we chose cis-nerolidol for further homology modelling and ligand docking. The results of molecular simulation and site-directed mutagenesis indicated that two amino acids, Lys74 and Pro121, in the protein binding pocket are the key amino acids involved in the binding of cis-nerolidol. The Lys74 residue may participate in specific recognition of ligands, and the Pro121 residue plays a crucial role in ligand binding and release by changing the binding pocket environment and stabilizing the conformation of the C-terminus of AlinOBP5.

Aims: We present 11 high-precision photometric transit observations of the transiting super-Earth planet GJ1214b. Combining these data with observations from other authors, we investigate the ephemeris for possible signs of transit timing variations (TTVs) using a Bayesian approach. Methods: The observations were obtained using telescope-defocusing techniques, and achieve a high precision with random errors in the photometry as low as 1mmag per point. To investigate the possibility of TTVs in the light curve, we calculate the overall probability of a TTV signal using Bayesian methods. Results: The observations are used to determine the photometric parameters and the physical properties of the GJ1214 system. Our results are in good agreement with published values. Individual times of mid-transit are measured with uncertainties as low as 10s, allowing us to reduce the uncertainty in the orbital period by a factor of two. Conclusions: A Bayesian analysis reveals that it is highly improbable that the observed transit times is explained by TTV, when compared with the simpler alternative of a linear ephemeris., Submitted to A&A

Multi-gripper stretch forming (MGSF) is a new flexible forming process compared to traditional stretching forming process. Two kinds of MGSF process, back-vertical drawing (BVD) and front-vertical drawing (FVD) are compared in this study. Spherical-curved part is selected as the research object, and the finite numerical modes for BVD and FVD have been established, and the simulation results are carried out by dynamic explicit finite element analysis. The numerical results indicated that the sheet metal can get the shape of the die at a lower strain ratio and the stretch strain distribution was more uniform by the FVD, which can improve the forming quality of the formed parts. In addition, the sheet metal can be formed by FVD under smaller hydraulic cylinder strokes. The results may provide useful guidance on optimizing the MGSF equipment structure.

In the context of global climate change, human activities dramatically damage the consistency of hydrological time series. Peak Over Threshold (POT) series have become an alternative to the traditional Annual Maximum series, but it is still underutilized due to its complexity. Most literature about POT tended to employ only one threshold regardless of the non-stationarity of the whole series. Obviously, it is unwise to ignore the fact that our hydrological time series may no longer be a stationary stochastic process. Hence, in this paper, we take the daily runoff time series of the Yichang gauge station on the Yangtze River in China as an example, and try to shed light on the selection of the threshold provided non- stationarity of our time series. The Mann-Kendall test is applied to detect the change points; then, we gave different thresholds according to the change points to the sub-series. Comparing the goodness-of-fit of the series with one and several thresholds, it clearly investigates the series that employs different thresholds performs much better than that just fixes one threshold during the selection of the peak events.

A detailed study of the decay of the second‐harmonic generation (SHG) signals of several guest–host nonlinear optical polymer systems has been carried out. The decay of the SHG signal is found to be affected by surface and trapped space charges. A fast component is observed at a low poling field and is found to be mainly due to surface charges which orient the chromophores near the surface. A second component, associated with macroscopic polarization, is induced at high field. The intensity of the second component, which decays considerably slower than the fast component, rapidly increases when the poling field is greater than a threshold voltage. Above the temperature of glass transition Tg, a single exponential function gives a good fit to the shape of the second component of the SHG intensity decay curve. The time constant of the slow component is found to increase with successive poling‐decay cycles and reaches a steady‐state value after several cycles have been performed. This lengthening effect is f...

The dependence of the second harmonic generation (SHG) signal of an amorphous polymer system containing nonlinear optical (NLO) chromophores on the polarizing electric field is investigated. It is shown that under a weak poling field condition, the SHG intensity is proportional to Ep2, provided that the polarizing electric field Ep is greater than a threshold field Es. Above Es, the macroscopic polar orientational order is established. The lengthening of the relaxation time for polar orientational order with increasing Ep is also observed. Theoretical analysis shows that the relaxation time is proportional to the polar order initially induced by the polarizing field. Experiments have been carried out to confirm the theoretical prediction.

The relationship between juvenile hormone and ecdysteroid titers during the early stage of the last larval instar of the silkworm,Bombyx mori, was examined in this study. When larvae were fed 20-hydroxyecdysone-supplemented mulberry leaves throughout the last larval instar, 100% underwent supernumerary larval molting instead of metamorphosis. The application of juvenile hormone mimic during the early last instar did not induce supernumerary larval molting, but did delay metamorphosis. Temporal and quantitative ecdysteroid titer measurements revealed that in normal larvae the titers maintained very low levels (3–12 ng/ml) during the early stage of the last instar; however, in 20-hydroxyecdysone-treated larvae, levels ranging from 24 to 45 ng/ml were detected, and a major peak (246 ng/ml) was observed on day 6. These results show that very low ecdysteroid titer levels during the early stage of the last larval instar may play an important role in initiating decreases in juvenile hormone titers as well as in directing metamorphosis.

A vertical channel SONOS memory, which is compatible with current CMOS process and has four physical storage nodes per unit area, is fabricated and electrically evaluated. Comparing with a planar device, the array cell tuning is much easier since the channel length is no longer limited by array area. After reviewing key performances including program/erase (P/E) speeds, second bit effect, program disturbance, endurance, and retention on a NOR-type array, it is found that four physical bits/cell is hard to achieve due to a serious program disturb. Unavoidable high energy 2nd hot electron between neighbor cells is identified as the root cause. In this paper, operation procedures and array layouts, which are suitable for three physical bits per cell (3bits/cell), is then proposed.

Erase characteristics of a SONOS-based structure are emulated not only for n+-poly and p+-poly gates but also for TaN-gate+Al 2 O 3 combination. By incorporating our previous studies, performances including program, erase, and read disturb can be reviewed for both SONOS and TANOS devices. Unsurprisingly, it is hard to satisfy all requirements by using a SONOS device. In a TANOS device, an optimal bottom oxide thickness can be specified with the consideration of the three factors simultaneously. Moreover, it is found that conventional extrapolation methodology is inadequate to predict the lifetime of a TANOS device and tends to under-estimate the tolerable read bias.

The purpose of this study was to examine the mitogenic effects of 20-hydroxyecdysone on neurogenesis in mushroom bodies of the adult cockroach, Diploptera punctata. The occurrence of neurogenesis was studied immunocytochemically after in vivo labeling with 5-bromo-2'-deoxyuridine (BrdU). The number of BrdU-labeled cells in the mushroom bodies was high shortly after adult ecdysis, then gradually decreased, and proliferation ceased on day 8. 20-Hydroxyecdysone injection during the early adult stages significantly delayed the decrease in mitotic activity. Moreover, 20-hydroxyecdysone injection during the late stage stimulated quiescent mushroom body neuroblasts to initiate their mitotic activity in a dose-dependent manner. These results indicated that the mushroom body neuroblasts of this insect become quiescent in the maturing central nervous system, but retain the capacity for proliferation if exposed to appropriate environmental signals. We conclude that 20-hydroxyecdysone has a mitogenic effect on neurogenesis in mushroom bodies of this insect.

Second harmonic intensities of several polymer films containing nonlinear optical chromophores have been investigated as a function of NLO Chromophore concentration, temperature and poling field strength.