Concentrations Of NF Research Articles

Plasma neurofilament analysis in VITALITY-ALS

Objective: To evaluate correlations between neurofilament (Nf) concentrations and clinical characteristics and disease progression using a large longitudinal dataset from VITALITY-ALS (ClinicalTrials.gov identifier: NCT02496767), a 48-week, randomized, double-blind, placebo-controlled clinical trial of tirasemtiv in people with ALS (pALS). Methods: Plasma was collected at baseline and every 8 weeks thereafter. Results were compared between treatment groups and evaluated by clinical characteristics and over time. Pearson’s correlation coefficients (r) were calculated to evaluate associations between Nf concentrations and slow vital capacity (SVC), Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) score, and pre-study/in-study rates of disease progression (psRDP/isRDP). Results: Nf measurements were available from 101 placebo- and 161 tirasemtiv-treated people with ALS (pALS). There were no significant differences in Nf between placebo and tirasemtiv groups at any time point; further analyses grouped all samples. At baseline, Nf concentration did not differ by multiple clinical characteristics. Baseline Nf light chain (NfL) concentration correlated with the psRDP (r = 0.50, p < 0.001) and isRDP (r = 0.53, p < 0.0001). Phosphorylated Nf heavy chain (pNfH) demonstrated a similar, but less robust, pattern of results. Baseline Nf concentration correlated with change in SVC and ALSFRS-R score over time. Plasma pNfH concentration continuously decreased over time. There was no meaningful change in plasma NfL concentration over the study period. Conclusions: In this large longitudinal study, baseline NfL concentration correlated with multiple markers of disease progression. The findings suggest Nfs show promise primarily as prognostic markers for pALS, particularly for those with rapid disease progression.

Simultaneous voltammetric detection of benzene, naphthalene and anthracene from water using boron-doped diamond electrode

In this study, a simple, fast and sensitive voltammetric detection using boron-doped diamond (BDD) electrode was proposed for simultaneous quantification of benzene (BZ), naphthalene (NF) and anthracene (AC) from priority organic pollutants class in real tap water. The electrochemical behaviors of individual and simultaneous BZ, NF and AC studied by cyclic voltammetry (CV) on BDD electrode showed a large separation between their oxidation potential, which allowed the development of simple simultaneous detection method. Differential-pulse voltammetry (DPV) technique operated at step potential of 5 mV and modulation amplitude of 200 mV enabled to reach the lowest limits of detection of 0.40 μM for BZ, 0.04 μM for NF and 0.70 nM for AC, which is appropriate for water quality control related to their environmental quality standards. No significant influence of chloride ions was found and the method was validated in real tap water and surface water spiked with known concentrations of BZ, NF and AC, which proved the practical utility of the method for water quality control.

A decoupling method to compute near field and far field exposure concentrations.

In the near field/far field (NF/FF) dispersion construct, the analytical solutions for the NF and FF concentration equations, respectively denoted CNF(t) and CFF(t) in mg/m3, are coupled in their mathematical derivation. Depending on the form of the contaminant emission rate function G(t) (mg/min), deriving CNF(t) and CFF(t) can range from being relatively easy to impossible. A method is presented to more easily approximate these concentration functions. The method decouples the NF and FF equations by treating the NF as an isolated well-mixed space with volume VNF (m3) and supply/exhaust airflow rate β(m3) and treating the FF as an isolated well mixed-space with volume V (m3) and supply/exhaust airflow rate Q (m3). Assuming that each space contains a source with the same contaminant emission rate function G(t), a contaminant concentration function is derived for the FF zone, denoted CWMR1(t), and an independent contaminant concentration function is derived for the NF zone, denoted CWMR2(t). Deriving a concentration function for a single zone is far easier than deriving coupled concentration functions. It is shown that the sum CWMR1(t) + CWMR2(t) provides an excellent approximation of CNF(t) and that CWMR1(t) provides an excellent approximation of CFF(t). A discrete-time numerical solution for the CNF(t) and CFF(t) system based on a Markov matrix is also presented.

Mechanical and antibacterial properties of an experimental flowable composite containing Nb2O5 and NF_TiO2 nanoparticles.

This study developed an experimental flowable composite incorporated with niobium pentoxide (Nb2O5) combined or not with titanium dioxide co-doped with fluorine and nitrogen (NF_TiO2) and evaluated the mechanical and antibacterial properties. The experimental flowable composite (TEGDMA + BisGMA 1:1 + 60%wt – inorganic filler – borosilicate 0.7 μm) was formulated according to the type and concentration of Nb2O5 and NF_TiO2 (0.5, 1, 1.5 and 2 wt%) or NF_TiO2 + Nb2O5 (0.25, 0.5, 0.75 and 1 wt% - 1:1). The control groups were formed by the experimental composite without the incorporation of Nb2O5 and/or NF_TiO2 (GC-E) and by a commercial flowable composite (GC). The characterization of the surface of the composite and its particles was carried out using scanning electron microscopy (SEM) and energy dispersive x-rays (EDX). Specimens were manufactured and subjected to mechanical tests of flexural strength (FS) (n = 12), flexural modulus (FM) (n = 12), roughness (Ra) (n = 10), microhardness (n = 10), and contact angle (n = 10); and, to evaluate the antibacterial activity, they were submitted to tests of biofilm formation against S. mutans (CFU/mL) (n = 5), biofilm biomass by dry weight (n = 5) and confocal laser microscopy (%LIVE/DEAD) (n = 5). Data were submitted to one-way ANOVA and Tukey's post-hoc and, those that were not homoscedastic, but with normality, were submitted to Welch's ANOVA and Games-Howell's post-hoc. Dunnet's test was used to compare the controls with the other experimental groups (α = 5). The Nb2O5 particles had an average size of 32.4 μm and the nanoparticles (NPs) of NF_TiO2, 10 nm. EDX analysis identified isolated peaks of N, F, Ti, and Nb confirming the presence of these particles in the resin matrix. The 1.5% NF_TiO2 group had a higher FS and FM than the controls (p < 0.05). GC showed higher microhardness between groups (p < 0.05). There was no difference between the experimental groups regarding contact angle and roughness (p > 0.05), except for GC, which had the highest Ra values and the lowest contact angle between groups (p < 0.05). Composites containing 0.5%, 1%, 1.5%, and 2% Nb2O5, 1%, 1.5%, and 2% NF_TiO2 and 2% Nb2O5 + NF_TiO2 showed lower biofilm formation (p < 0.05), lower total biofilm biomass (p < 0.05), and a higher percentage of dead cells (44%, 52%, 52%, 79%, 42% 43%, 62%, 65%, respectively) than GC and GC-E (5% and 1%, respectively). It is concluded that the incorporation of 1.5% NF_TiO2 promoted a greater FS and FM among the experimental composites and that the addition of Nb2O5 particles (0.5%, 1%, 1.5%, and 2%), NF_TiO2 (1%, 1.5% and 2%) and the combination Nb2O5 + NF_TiO2 (2%) showed significant antibacterial effects.

Response of Fluorescence and Chlorophyll Physiological Characteristics of Typical Urban Trees to Ozone Stress

In this study, four typical urban landscaping tree species were selected, three open top air chambers with different ozone concentrations were set, and the responses of chlorophyll fluorescence, chlorophyll content and relative conductivity of the trees to ozone stress were studied. The results showed that with the increase in ozone concentration, the maximum photochemical efficiency, electron transfer quantum yield, electron transfer rate (ETR) and chlorophyll content of the different tree species decreased significantly, while the relative conductivity of the different tree species increased significantly. Compared with the ozone concentration of NF, under an ozone concentration of nf40 and nf80, the decline in the rate of Fv/Fm of Koelreuteria paniculata and Ginkgo biloba was 2.47 and 2.28 times that of Pinus bungeana and Platycladus orientalis, respectively, and the increase in the rate of relative conductivity of K. paniculata and G. biloba was 2.11 and 1.28 times that of P. bungeana and P. orientalis, respectively. Under different ozone concentrations, the photochemical efficiency, electron transfer rate, chlorophyll content and relative conductivity of P. bungeana and P. orientalis were higher than those of Ginkgo biloba and K. paniculata, indicating that K. paniculata and G. biloba were more sensitive to ozone. This study is of great significance for improving urban environmental quality and ozone control and also provides a basis for selecting tree species with strong ozone tolerance.

Two-phase mixture simulation of the performance of a grooved helical microchannel heat sink filled with biologically prepared water-silver nanofluid: Hydrothermal characteristics and irreversibility behavior

• A novel heatsink with grooved helical microchannels is suggested. • Biologically synthesized water-Ag nanofluid is considered as the working fluid. • First and second law analysis of nanofluid flow inside the heatsink are evaluated. • Heatsink with staggered grooved helical channels has best first-law performance. • Grooving the helical channel entails an increment in the entropy generation. The present paper investigates the influence of using two grooved channel geometries on the hydrothermal performance of a helical microchannel heat sink. The results were compared with those obtained for the plain channel geometry. Based on the results, the highest flow mixing is observed for the staggered grooved configuration. Moreover, the convective heat transfer coefficient enhances by nearly 70% and 17% for the MCHS with the staggered and parallel grooved channels, respectively, as compared to that with the plain channel. The influence of Reynolds number ( Re ) escalation on the convective heat transfer coefficient is insignificant, while a 21% increase is obtained when NF concentration is increased from 0% to 1%. Furthermore, the increase of φ in the grooved configurations is more effective than that in the plain configuration. In addition, the lowest thermal resistance and temperature uniformity factors were obtained for the staggered grooved configuration. Besides, the parallel grooved configuration represents the highest frictional entropy generation rates among the three studied geometries due to the considerable reduction of the fluid flow cross-section area between the groove ribs. The highest heat transfer coefficient and pressure drop are associated with the staggered grooved configuration. For the plain, parallel grooved, and staggered grooved configurations, the increase of Re from 500 to 2000 escalates the NF pressure drop by 2730%, 4420%, and 4460%, respectively. Therefore, the highest performance evaluation criterion of more than unity was obtained for the MCHS with the staggered grooved channels for the studied range of Re (500–2000). The numerical analysis was also performed to evaluate the influence of groove pitch on the hydrothermal performance of the staggered groove channel for the pitch range of 0.15 mm to 0.75 mm. The results demonstrated that the highest PEC is associated with the groove pitch of 0.75 mm.

Upregulated Retinal Neurofilament Expression in Experimental Optic Neuritis

ABSTRACT In optic neuritis (ON), transient thickening of the macular retinal nerve fibre layer (RNFL) can be observed. This optical coherence tomography-based observation is not understood. The axonal diameter correlates with the neurofilament (Nf) protein content, but there are no data on the retinal tissue concentration of Nfs. The myelin-oligodendrocyte-glycoprotein (MOG) induced experimental autoimmune encephalomyelitis (EAE) model was used to investigate the retinas of Brown Norway rats with (i) visual evoked potentials (VEP) confirmed ON, (ii) VEP confirmed absence of ON and (iii) control animals. Twenty retinas were collected from MOG-EAE and control rats 27 days after immunisation. Retinal tissue Nf concentrations per total protein (μg/mg) were significantly higher in MOG-EAE rats with ON (median 4.29, interquartile range [IQR] 3.41–5.97) compared with MOG-EAE rats without ON (1.14, IQR 1.10–1.67) or control rats (0.93, IQR 0.45–4.00). The data suggest that up-regulation of Nf expression in the retinal ganglion cells precedes development of RNFL atrophy and plausibly explains the transient increase of axonal diameter and RNFL thickening.

Assessment of exposure determinants and exposure levels by using stationary concentration measurements and a probabilistic near-field/far-field exposure model.

Background: The Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation requires the establishment of Conditions of Use (CoU) for all exposure scenarios to ensure good communication of safe working practices. Setting CoU requires the risk assessment of all relevant Contributing Scenarios (CSs) in the exposure scenario. A new CS has to be created whenever an Operational Condition (OC) is changed, resulting in an excessive number of exposure assessments. An efficient solution is to quantify OC concentrations and to identify reasonable worst-case scenarios with probabilistic exposure modeling. Methods: Here, we appoint CoU for powder pouring during the industrial manufacturing of a paint batch by quantifying OC exposure levels and exposure determinants. The quantification was performed by using stationary measurements and a probabilistic Near-Field/Far-Field (NF/FF) exposure model. Work shift and OC concentration levels were quantified for pouring TiO 2 from big bags and small bags, pouring Micro Mica from small bags, and cleaning. The impact of exposure determinants on NF concentration level was quantified by (1) assessing exposure determinants correlation with the NF exposure level and (2) by performing simulations with different OCs. Results: Emission rate, air mixing between NF and FF and local ventilation were the most relevant exposure determinants affecting NF concentrations. Potentially risky OCs were identified by performing Reasonable Worst Case (RWC) simulations and by comparing the exposure 95 th percentile distribution with 10% of the occupational exposure limit value (OELV). The CS was shown safe except in RWC scenario (ventilation rate from 0.4 to 1.6 1/h, 100 m 3 room, no local ventilation, and NF ventilation of 1.6 m 3/min). Conclusions: The CoU assessment was considered to comply with European Chemicals Agency (ECHA) legislation and EN 689 exposure assessment strategy for testing compliance with OEL values. One RWC scenario would require measurements since the exposure level was 12.5% of the OELV.

Impedance modulated dielectric and magnetic properties of BCT-NF multiferroic composite

Dual nature of multiferroic composites embellishes it as a promising candidate for the application in electronic industry. In this paper, we report the structural, dielectric, electrical and magnetic properties of 1-x (Ba0.96Ca0.04TiO3)-x (NiFe2O4) (BCT-NF) multiferroic composite material synthesized using the solid-state reaction method. X-ray diffraction showed the simultaneous existence of ferroelectric and ferromagnetic phase with tetragonal and spinel structure respectively. Whereby, Raman spectroscopy confirmed the existence of both phases by indicating the intense peak ranges from 566 cm−1 to 545 cm−1. Transmission electron microscopy micrograph presented the crystalline nature of all the prepared samples. Electrical analysis shows high value of ε’ with low loss factor confirming the compatibility nature of both the phases with low conductivity and minimal creation of oxygen vacancies. However, the composition x = 0.2 shows optimum dielectric and impedance properties due to the size dependency. Curie temperature was found to shift towards higher range with an increase in NF concentration. Magnetic study revealed the increasing nature of Ms and TB with increasing ferromagnetic concentration. The optimum value for TB and Ms was found to be 102 K and 36 emu/g, respectively.

Chitosan-silicon nanofertilizer to enhance plant growth and yield in maize (Zea mays L.)

We report a novel chitosan-silicon nanofertilizer (CS–Si NF) wherein chitosan-tripolyphosphate (TPP) nano-matrix has been used to encapsulate silicon (Si) for its slow release. It was synthesied by ionic gelation method and characterized by dynamic light scattering (DLS), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and atomic absorption spectrophotometry (AAS). The developed CS-Si NF exhibited slow release of Si and promoted gowth and yield in maize crop. Seeds primed with different concentrations of CS-Si NF (0.04–0.12%, w/v) exhibited up to 3.7 fold increased seedling vigour index (SVI) as compared with SiO2. Its foliar spray significantly induced antioxidant-defence enzymes’ activities and equilibrated cellular redox homeostasis by balancing O2−1 and H2O2 content in leaf as compared with SiO2. Application of nanofertilizer (0.01–0.16%, w/v) stirred total chlorophyll content (21.01–25.11 mg/g) and leaf area (159.34–166.96 cm2) to expedite photosynthesis as compared with SiO2. In field experiment, 0.08% CS-Si NF resulted in 43.4% higher yield/plot and 0.04% concentration gave 45% higher test weight as compared with SiO2. Fecund and myriad effects of developed nanofertilizer over SiO2 could be attributed to slow/protective release of Si from nanofertilizer. Overall, results decipher the enormous potential of CS-Si NF for its use as a next generation nanofertilizer for sustainable agriculture.

Cerebrospinal fluid light and heavy neurofilament level increased in anti-N-methyl-d-aspartate receptor encephalitis.

BackgroundNeurofilaments (Nf) are a series of highly specific scaffolding proteins of neurons. Neurofilament light chains (Nf‐L) and the heavy one (Nf‐H) are subunits of Nf, and they are recognized as potent productions of neural damage. The concentrations of Nf aggrandized significantly in neurological disease including neuromyelitis optica, multiple sclerosis, and Alzheimer's disease. However, whether Nf in cerebrospinal fluid (CSF) elevated in anti‐N‐methyl‐d‐aspartate receptor (NMDAR) encephalitis is unclear. Here, we aimed to detect whether CSF Nf is altered in NMDAR and whether changes in CSF Nf can serve as an objective and effective biomarker to evaluate disease severity and prognosis.MethodsWe collected 24 anti‐NMDAR encephalitis patients, 11 viral meningoencephalitis/encephalitis (VM) patients, and 21 controls in this study. CSF Nf‐L, Nf‐H, and cytokine levels (IL‐1β, IL‐6, and IL‐17A) were determined by enzyme‐linked immunosorbent assay (ELISA) and compared between groups. We evaluated patients’ clinical outcomes or prognosis according to modified Rankin scale (mRS) score.ResultsCompared with controls, both CSF Nf‐L and Nf‐H levels were significantly increased in anti‐NMDAR encephalitis patients. While compared with VM patients, only Nf‐L were increased in anti‐NMDAR encephalitis patients. Moreover, CSF Nf‐L were positively correlated with concentration of cytokines (IL‐1β, IL‐17A) and mRS scores in anti‐NMDAR encephalitis patients. After treatment, both CSF Nf‐L and Nf‐H levels decreased. Furthermore, the Nf‐L during follow‐up positively correlated with 3‐month mRS scores, and ΔNf‐L positively correlated with ΔmRS.ConclusionsBriefly, CSF Nf‐L levels notably increased in anti‐NMDAR encephalitis patients in acute phase and positively correlated with disease severity. It could be considered as a useful indicator for clinical outcomes and prognosis.

Thermophysical profile of SiC–CuO/C nanocomposite in base liquid ethylene glycol

The experimental data on the viscosity and thermal conductivity (TC) of ethylene glycol (EG)-based hybrid nanofluids (HyNFs) dispersed with a SiC–CuO/C nanocomposite (NC) is reported for the first time. The rheological behavior and dynamic viscosity have been analyzed with a computer controlled rotational rheometer over a temperature range from 298.15–353.15 K and shear rate from 20 to 200 s−1. The TC was measured using transient hot-wire method for NF concentrations up to 3.13 wt%. The effect of the temperature and volume fraction of the nanoparticles (NPs) on the thermophysical properties were examined under atmospheric pressure. The experimental findings revealed that the TC increases with the concentration and temperature, while the viscosity increases with concentration and decreases with temperature as expected. HyNF exhibit substantially higher TC and viscosity enhancement compared to single-particle based NF under similar conditions. The enhanced properties of the HyNF could be attributed to the synergetic effects of the composite particles and the underlying physical mechanism in the fluid medium. The existing theoretical models failed to predict the experimental data. Herein, a new correlation is presented as a function of concentration and temperature for the TC and viscosity.

Neurofilament as Neuronal Injury Blood Marker in Preeclampsia.

Preeclampsia has been shown to be associated with changes in cerebral structure and cognitive function later in life. Nf (neurofilaments) are specific scaffolding proteins of neurons, and their quantification in serum has been proposed as a biomarker for neuroaxonal injury. We performed a prospective, longitudinal, single-center study at the University Hospital of Basel to determine serum Nf concentrations in pregnant women with singleton pregnancies and with high risk of preeclampsia or with early signs of preeclampsia. Enrollment started at 21 weeks of gestation, followed up with multiple visits until delivery. Sixty out of 197 women developed preeclampsia (30.5%). NfL (Nf light chain) was measured with a highly sensitive single molecule array (Simoa) assay, in addition to the established preeclampsia markers sFlt-1 (soluble fms-like tyrosine kinase-1) and PlGF (placental growth factor). The most important independent predictors of NfL were maternal age, number of pregnancies, and proteinuria. NfL levels increased during pregnancy and were significantly higher in women developing preeclampsia. The discriminatory accuracy of NfL, PlGF, and sFlt-1 in receiver operating characteristic curves analysis (area under the curve) of the overall group was 0.68, 0.81, and 0.84, respectively, and in women older than 36 years 0.7, 0.62, and 0.79, respectively. We conclude that increased axonal injury serum marker NfL predicts preeclampsia particularly in older women, with an accuracy similar to the established angiogenic factors. NfL may serve as an early indicator of preeclampsia-induced changes in cerebral structure and may help to stratify disease management.

Multicenter evaluation of neurofilaments in early symptom onset amyotrophic lateral sclerosis.

To examine neurofilament (Nf) concentrations according to symptom onset and clinical diagnostic certainty categories of amyotrophic lateral sclerosis (ALS). We measured Nf light chain (NfL) and phosphorylated Nf heavy chain (pNfH) CSF and NfL serum levels in patients with ALS with first symptom onset ≤6 months (n = 54) or >6 months (n = 135) from sampling, and patients with other neurologic diseases, differential diagnoses of a motor neuron disease (MND mimics), and other MND variants to determine the diagnostic accuracy in patients with ALS with early symptom onset. Samples were received multicentric and analyzed by ELISA and Simoa platform and related to other clinical measures. NfL and pNfH in CSF and NfL in serum were increased in early and later symptomatic phase ALS (p < 0.0001). CSF and serum NfL and CSF pNfH discriminated patients with ALS with early symptom onset from those with other neurologic diseases and MND mimics with high sensitivity (94%, 88%, 98%, and 89%, 100%, 78%) and specificity (86%, 92%, 91%, and 94%, 90%, 98%) and did not vary between clinical diagnostic categories of ALS in the early symptomatic phase group. Baseline NfL and pNfH levels were not significantly different in patients with ALS with clinical progression to definite or probable ALS at follow-up. The measurement of Nf has potential to enhance diagnostic accuracy of ALS in those presenting soon after symptom onset, and is measurable across multiple centers. This study provides Class II evidence that CSF and serum Nf concentrations discriminate ALS with early symptom onset from other neurologic diseases.

Safety evaluation of a milk-based protein powder produced by a novel manufacturing technique

TruActive™ NF is a novel, fat-free, milk-based protein powder to be added to food to increase protein content and is manufactured using non-thermal treatment to reduce potential pathogens most relevant to protecting public health. TruActive™ NF was evaluated for potential pathogens of concern to public health regulators; none were detected. The estimated daily intake (EDI) of TruActive™ NF at a 90th percentile consumption for the powder in nutritional beverages and bars is 14,700 mg/day. In vitro genotoxicity testing revealed that concentrations of TruActive™ NF up to 5000 μg/plate did not induce point mutations in selected strains. Oral administration of TruActive™ NF to male Sprague-Dawley rats in an in vivo mammalian chromosomal aberration assay did not induce chromosomal aberrations or significantly affect mitosis in bone marrow cells at 2000 mg/kg. Male and female Sprague-Dawley rats were administered TruActive™ NF at concentrations of 7.5%, 15%, and 30% of the diet during a 28-day subacute dietary study followed by a 14-day recovery period. Some parameters were altered at the 30% diet concentration. The No Observed Adverse Effect Level (NOAEL) in the 28-day dietary study was at 15% of the diet (11,812 mg/kg bw/day for male rats and 11,521 mg/kg bw/day for female rats).

The near field/far field model with constant application of chemical mass and exponentially decreasing emission of the mass applied

ABSTRACT The near field/far field (NF/FF) model is a contaminant dispersion construct that permits making airborne contaminant exposure estimates for an individual located close to an emission source. In the present analysis, chemical emission involves a constant mass rate of chemical application to surfaces, denoted I (mg/min), and an exponentially decreasing rate of emission of the chemical from the surfaces with rate constant α (min−1). The time-dependent emission rate function is: G(t), mg/min = I − I exp(− αt), where time t is in minutes. The exact time-dependent equations for the contaminant concentration in the NF and the FF are presented. These equations are used to revise a previous analysis of a study in which a penetrant liquid containing benzene was applied to parts on a work table in a test room. The previous analysis assumed that the benzene was applied as a bolus at the start of a 15-min use period, whereas the present analysis assumes the same total benzene mass was applied at a uniform rate over the 15-min use period, but with the same evaporation rate constant α. The new G(t) function leads to a lower 15-min time weighted average NF benzene concentration that better matches the experimental data. It is also shown that the exact equation for the NF concentration is well approximated by combining two well-mixed single-zone equations. The approximation method is mathematically simpler and obviates the need to derive the exact NF equation.

High-Speed Ultrasmooth Etching of Fused Silica Substrates in SF&lt;sub&gt;6&lt;/sub&gt;, NF&lt;sub&gt;3&lt;/sub&gt;, and H&lt;sub&gt;2&lt;/sub&gt;O-Based Inductively Coupled Plasma Process

This paper presents a new paradigm for high aspect ratio etching of fused silica substrates using a modified inductively coupled plasma (ICP) etch chamber. In particular, we have incorporated a stainless steel gas diffuser ring on the mechanical substrate clamping plate of the etcher to introduce NF3 and H2O gases right above the wafer, whereas SF6 is introduced through the ICP source. This configuration of plasma etching allows for incomplete breakdown of NF3 + H2O gas mixture, thereby creating a high local density of F, NF x , and HF (Hydrogen Fluoride) while achieving large flux of SFx+ ion bombardment. Using this configuration, source power of 2500 W, substrate power of 400 W, and SF6/NF3/H2O flow rates of 60/100/50 sccm, we were able to achieve a surface roughness of $\sim 5$ A at an etch rate of $\sim 1 \mu $ m/min. In situ residual gas analysis of the plasma conditions show high concentrations of F, HF, and SFx, along with a large concentration of NF x species. The highest etch rate was also found to be a function of the ion flux. The anisotropy of the etch was enhanced by the formation of an inert nickel fluoride/oxide skin layer on the sidewalls of the etched features. [2014-0214]

Effect of NF- κ B inhibitor PDTC on VEGF and endostatin expression of mice with Lewis lung cancer.

To investigate the effects of NF- κ B inhibitor pyrrolidine dithiocarbamate hydrochloride (PDTC) on vascular endothelial growth factor (VEGF) and endostatin expression in mice with Lewis lung cance; and its mechanism. Mice survival rate and anti-tumor effects were observed in different concentrations of NF- κ B inhibitor PDTC after the Lewis lung cancer mice model was established. VEGF and endostatin expressions were detected by immunohistochemical assay. Lewis lung cancer was be inhibited by 0.5 mg/kg, 1.5 mg/kg and 3.0 mg/kg of NF- κ B inhibitor PDTC (P<0.05). Microvessel density (MVD) in 0.5 mg/kg, 1.5 mg/kg and 3.0 mg/kg NF- κ B inhibitor PDTC groups were significantly lower than the control group (P<0.05). Immunohistochemical assay results showed that VEGF and endostatin expressions in the 0.5 mg/kg, 1.5 mg/kg and 3.0 mg/kg NF-κ B inhibitor PDTC groups were significantly lower than the control group (P<0.05). Western blot results also showed that NF- κ B inhibitor PDTC could inhibit VEGF and endostatin expressions in tumor tissues. NF- κ B inhibitor PDTC can inhibit tumor formation and reduce tumor angiogenesis in mice with Lewis lung cancer; and its mechanism maybe associated to VEGF and endostatin down-regulation.

Faecal nitrogen of browser and mixed feeder game species during different seasons

A practical measure of assessing periods of potential nutritional stress of game species is needed in the management of these species in the Acacia karroo Riparian Thicket of the central Free State. The objectives of the study were to determine Nf concentration of four game species (browsers and mixed feeders) during different seasons, compare Nf with leaf phenology patterns, and assess whether Nf reaches levels at which body condition loss can be expected. A seasonal pattern was observed with the lowest Nf concentrations recorded during late winter, which correlated with the seasonal phenology pattern (leaf carriage) of the winter-deciduous tree species. The Nf concentrations (g N kg−1 dung DM) of giraffe ranged from 18.3 (late winter) to 36.7 (summer) and that of kudu from 13.6 to 33.2. Likewise, the Nf of impala ranged from 16.9 to 28.0 and that of eland from 16.3 to 34.9. Access to evergreen woody species during the late-winter period proved to be essential in avoiding condition loss that corresponds with Nf levels below published critical levels (<16). In the absence of evergreen species, supplementary feeding is essential. Faecal nitrogen proved to be a useful indicator of seasonal trends in the nutritional status of browsing game species.

Ferroelectric and dielectric properties of ferrite-ferroelectric ceramic composites

Particulate composites of ferrite and ferroelectric phases with xNiFe2O4 (NF) and (1 − x)Pb0.988(Zr0.52Ti0.48)0.976Nb0.024O3 (where x = 2, 10, 20, 30, 50, 70, and 100 wt. %) were prepared in situ by sol-gel method. The presence of a diphase composition was confirmed by X-ray diffraction while the microstructure of the composites was studied by scanning electron microscopy revealing a good mixing of the two phases and a good densification of the bulk ceramics. The dielectric permittivity shows usual dielectric dispersion behavior with increasing frequency due to Maxwell-Wagner interfacial polarization. AC conductivity measurements made in frequency range 1 Hz-1 MHz suggest that the conduction process is due to mixed polaron hopping. The effect of NF phase concentration on the P-E and M-H hysteresis behavior and dielectric properties of the composites was investigated. At low NF concentration a sharp ferro-paraelectric transition peak can be observed at around 360 °C while for higher NF concentrations a trend to a diffuse phase transition occurs. All the composite samples exhibit typical ferromagnetic hysteresis loops, indicating the presence of ordered magnetic structure.