LitSearch-NOx (2024)

Project ID

4767

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NAAQS

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April 12, 2023, 4:32 a.m.

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Journal Article

Abstract  Purpose: Despite the different etiology of primary open angle glaucoma (POAG), primary angle closure glaucoma (PACG), and pseudoexfoliative glaucoma (PEXG), several studies have suggested that these forms of glaucoma have overlapping genetic risk factors. Therefore, the aim of this study was to evaluate the role of genetic variants recently associated with POAG in different types of glaucoma in Pakistani POAG, PACG, and PEXG patient cohorts.

Methods: Six variants in CDKN2B-AS1 (rs4977756), CDKN2B (rs1063192), ATOH7 (rs1900004), CAV1 (rs4236601), TMCO1 (rs4656461), and SIX1 (rs10483727) were genotyped using TaqMan assays. A total of 513 unrelated patients with glaucoma (268 with POAG, 125 with PACG, and 120 with PEXG) and 233 healthy controls were included in the study. Genotypic and allelic associations were analyzed with a chi-square test.

Results: The frequency of the G allele of TMCO1 rs4656461 was significantly lower in the patients with POAG (p=0.003; OR [odds ratio]=0.57), PACG (p=0.009; OR=0.52), and PEXG (p=0.01; OR=0.54) compared to the control individuals. The T allele of ATOH7 rs1900004 was observed less frequently in the patients with PACG (p=0.03; OR=0.69) compared to the control individuals. The A allele of CAV1 rs4236601 was found more frequently in the patients with POAG (p=0.008; OR=1.49) compared to the control individuals. This study demonstrates that the TMCO1 rs4656461 variant is associated with POAG, PACG and PEXG in the Pakistani population. Our study was unable to confirm previous associations reported for variants in CDKN2B-AS1, CDKN2B, and SIX1 with any type of glaucoma.

Conclusions: In conclusion, we found consistent evidence of the significant association of three common variants in TMCO1, ATOH7, and CAV1.

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Journal Article

Abstract  The substances responsible for the yellowing of wool treated with nitric acid are two amino acid constituents of the fibre: tryptophan and tyrosine. Nitric acid penetrates the fibres and carries out electrophilic aromatic substitution on the two above-mentioned amino acid residues, producing different colour yields. The intensity of yellowing depends in various ways on the treatment conditions (time, temperature, nitric acid concentration, agitation, and liquor ratio). Yellowing evaluation shows abnormal yellowing depending on acid concentration in the range 5.6-5.9 M. Working in this region makes it possible to use the chromatic reaction in order to show the damage done to wool fibres by the oxidising agents utilised in normal antifelting treatments. Wool damage by the oxidants is usually evaluated by dyeing methods based on different affinity of damaged fibres. By contrast, the xanthoproteic reaction yields chromogens as a function of the accessibility of tryptophan and tyrosine residues for the action of nitric acid on damaged fibres, and can be used for assessing the degree of antifelting treatment and its possible unevenness through the development on the treated wool of a yellow coloration more intense than on untreated wool.

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Journal Article

Abstract  A multi-season N-15 tracer recovery experiment was conducted on an Oxisol cropped with wheat, maize and sorghum to compare crop N recoveries of different fertilisation strategies and determine the main pathways of N losses that limit N recovery in these agroecosystems. In the wheat and maize seasons, N-15-labelled fertiliser was applied as conventional urea (CONV) and urea coated with a nitrification inhibitor (DMPP). In sorghum, the fate of N-15-labelled urea was monitored in this crop following a legume ley pasture (L70) or a grass ley pasture (G100). The fertiliser N applied to sorghum in the legume-cereal rotation was reduced (70 kg N ha(-1)) compared to the grass-cereal (100 kg N ha(-1)) to assess the availability of the N residual from the legume ley pasture. Average crop N recoveries were 73 % (CONV) and 77 % (DMPP) in wheat and 50 % (CONV) and 51 % (DMPP) in maize, while in sorghum were 71 % (L70) and 53 % (G100). Data gathered in this study indicate that the intrinsic physical and chemical conditions of Oxisols can be extremely effective in limiting N losses via deep leaching or denitrification. Elevated crop N-15 recoveries can be therefore obtained in subtropical Oxisols using conventional urea while in these agroecosystems DMPP urea has no significant scope to increase fertiliser N recovery in the crop. Overall, introducing a legume phase to limit the fertiliser N requirements of the following cereal crop proved to be the most effective strategy to reduce N losses and increase fertiliser N recovery.

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Journal Article

Abstract  Biological reduction of nitric oxide (NO) with ferrous chelate is the main step for the chemical absorption-biological reduction (CABR) integrated method to remove nitrogen oxide (NOx) from flue gas. Heterotrophic bacteria play a dominant role in the CABR process, and their reactivity is seriously affected by carbon source and electron donor. Therefore, the consumption and utilization pathways of glucose were investigated. The study on glucose metabolites shows that the accumulation of acetate should be alleviated, which make it possible to keep running the bioreactor normally, although the volatile fatty acids (VFAs) may be beneficial as an electron donor for the reactions in CABR. The reduction of complex NO mainly depends upon the concentration of Fe(II) and acetate. The main utilization pathway of glucose can be expressed as glucose -> pentanoic acid -> butyric acid -> propionic acid -> acetic acid -> CO2. Under experimental conditions of 670 mg m(-3) NO inlet concentration, 0-10% O-2 concentration, and 8 h of hydraulic retention time (HRT), more than half of inlet elemental carbon (glucose) was released in the form of gas after 240 h of operation. VFAs, especially acetic acid, mainly existed in the liquid phase, and CO2 was mainly observed in the gas phase.

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Journal Article

Abstract  Secondary organic material (SOM) produced by the oxidation of anthropogenic volatile organic compounds can be light-absorbing (i.e., brown carbon). Spectral data of the optical properties, however, are scarce. The present study obtained the continuous spectra of the real and imaginary refractive indices (m = n - ik) in the ultraviolet (UV)- to-visible region using spectroscopic ellipsometry for n and UV-visible spectrometry for k. Several different types of SOM were produced in an oxidation flow reactor by photooxidation of toluene and m-xylene for variable concentrations of nitrogen oxides (NOx). The results show that the k values of the anthropogenically derived material were at least 10 times greater than those of the biogenically derived material. The presence of NOx was associated with the production of organonitrogen compounds, such as nitro-aromatics and organonitrates, which enhanced light absorption. Compared with the SOM derived from m-xylene, the toluenederived SOM had larger k values, as well as a greater NOx-induced enhancement, suggesting different brown-carbonforming potentials of different aromatic precursor compounds. The results imply that anthropogenic SOM produced around urban environments can have an important influence on ultraviolet irradiance, which might consequently influence photochemical cycles of urban pollution.

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Journal Article

Abstract  An unsymmetrical hexatopic carboxylate acid (H6-1) ligand containing one acrylamide unit and two triazole groups was designed and synthesized, and then used to construct a metal-organic framework (MOF Cu-ABTA) via a solvothermal reaction with Cu(NO3)(2). A powder X-ray diffraction investigation indicated that the MOF Cu-ABTA possesses a (3,24)-connected rht-network, as does our previously reported MOF NTU-105 with three triazole groups. The gas sorption measurements revealed that Cu-ABTA shows high porosity and a very high H-2-uptake capability with a strong H-2 binding affinity as demonstrated by the enhanced isosteric heat of adsorption, which make it a highly promising candidate for clean energy storage.

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Journal Article

Abstract  Diesel engines are most frequently used in vehicles because of their high efficiency and durability. However, nitrogen oxide (NOx) and particulate matter (PM) from diesel engines are became problem. Recently, the premixed charged compression ignition (PCCI) technique has been studied specifically to reduce NOx and PM emissions simultaneously. While the PCCI engine has the advantage of reducing NOx and PM emissions, control of the combustion phase is difficult. Therefore, it is very important to understand the flame developing process and heat release pattern in a real PCCI engine. However, most research into the characteristics of PCCI combustion has used an optical access engine. This paper describes the combustion characteristics obtained using a micro-Cassegrain sensor and discusses how the sensor can be used to directly detect the flame characteristics for future control of PCCI combustion. From this research, the differences of flame characteristics between PCCI engine and conventional diesel engine were clarified.

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Journal Article

Abstract  The reaction of NO with the hydroxylated rutile TiO2(110)-1 x 1 surface (h-TiO2) was investigated as a function of NO coverage using temperature-programmed desorption. Our results show that NO reaction with h-TiO2 leads to formation of NH3, which is observed to desorb at similar to 400 K. Interestingly, the amount of NH3 produced depends nonlinearly on the dose of NO. The yield increases up to a saturation value of similar to 1.3 x 10 (13) NH3/cm(2) at a NO dose of 5 x 10(-13) NO/cm(2), but subsequently decreases at higher NO doses. Preadsorbed H2O is found to have a negligible effect on the NH3 desorption yield. Additionally, no NH3 is formed in the absence of surface hydroxyls (HObs) upon coadsorption of NO and (HO)-O-2 on a stoichiometric TiO2(110) (s-TiO2(110)). On the basis of these observations, we conclude that nitrogen from NO has a strong preference to react with HObs on the bridge-bonded oxygen rows (but not with H2O) to form NH3. The absolute NH3 yield is limited by competing reactions of HOb species with titanium-bound oxygen adatoms to form H2O. Our results provide new mechanistic insight about the interactions of NO with hydroxyl groups on TiO2(110).

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Journal Article

Abstract  nitrogen (N) budget for Denmark has been developed for the years 1990 to 2010, describing the inputs and outputs at the national scale and the internal flows between relevant sectors of the economy. Satisfactorily closing the N budgets for some sectors of the economy was not possible, due to missing or contradictory information. The budgets were nevertheless considered sufficiently reliable to quantify the major flows. Agriculture was responsible for the majority of inputs, though fisheries and energy generation also made significant contributions. Agriculture was the main source of N input to the aquatic environment, whereas agriculture, energy generation and transport all contributed to emissions of reactive N gases to the atmosphere. Significant reductions in inputs of reactive N have been achieved during the 20 years, mainly by restricting the use of N for crop production and improving livestock feeding. This reduction has helped reduce nitrate leaching by about half. Measures to limit ammonia emissions from agriculture and mono-nitrogen oxides (NOx) emissions from energy generation and transport, has reduced gaseous emissions of reactive N. Much N flows through the food and feed processing industries and there is a cascade of N through the consumer to solid and liquid waste management systems. The budget was used to frame a discussion of the potential for further reductions in losses of reactive N to the environment. These will include increasing the recycling of N between economic sectors, increasing the need for the assessment of knock-on effects of interventions within the context of the national N cycle.

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Journal Article

Abstract  This paper investigates the flowthrough and over two-dimensional rectangular roughness elements, arranged in a building-street canyon geometry through a series of experiments. Geometries of different packing densities of the roughness elements (lambda(p)) were examined and the packing density values ranged from lambda(p) = 0.30 to 0.67. The purpose of the work is: (i) to investigate the flow physics observed both at the boundary layer scale as well as at the scale within the roughness elements for a range of packing densities, (ii) to deduce parameterizations of the adjusted rough boundary layer and their variation with a change in the packing density, and (iii) given a particular interest in and application to the urban atmosphere, a final aim at the roughness-element scale is to deduce the variation of the breathability with the packing density variation. Particle image velocimetery measurements of the velocity flow field as well as the turbulent kinetic energy and the Reynolds Stress (within and up to well-above the street canyons) were conducted. The results reveal qualitative flow features as well as features of the adjusted boundary layer structure-in particular the roughness and inertial sublayers, which can be associated with the surface roughness length, zero-plane displacement thickness, and the friction velocity. The lowest friction velocities are exhibited in the geometries with the highest-and lowest packing densities while the maximum friction velocities are observed in the medium-packed geometries. The exchange processes and breathability at the level of the roughness elements top were characterized and quantified by a mean exchange velocity. The results show that unlike friction velocity, the normalized exchange velocity (over the mean bulk velocity) for the most dense and sparse geometries differ by more than 80%, with the denser-packed geometries exhibiting lower exchange velocities; this is shown to be related with the thickness of the developed roughness sublayer. (C) 2014 AIP Publishing LLC.

Journal Article

Abstract  The quaternary benzo[c]phenanthridine alkaloid, chelerythrine (CHE), is of great practical and research interest because of its pronounced, widespread physiological effects, primarily antimicrobial and anti-inflammatory, arising from its ability to interact with proteins and DNA. Although CHE was originally shown to possess anti-inflammatory properties, its effects on acute gastric ulcer have not been previously explored. The aim of the present study is to evaluate the protective effect of CHE on ethanol induced gastric ulcer in mice. Administration of CHE at doses of 1, 5 and 10mg/kg bodyweight prior to ethanol ingestion dose-dependently inhibited gastric ulcer. The gastric mucosal lesion was assessed by ulcer area, gastric juice acidity, myeloperoxidase (MPO) activities, macroscopic and histopathological examinations. CHE significantly reduced the gastric ulcer index, myeloperoxidase activities, macroscopic and histological score in a dose-dependent manner. In addition, CHE also significantly inhibited nitric oxide (NO) concentration, pro-inflammatory interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) level in serum and gastric mucosal in the mice exposed to ethanol induced ulceration in a dose-dependent manner. In addition, immunohistochemical analysis revealed that CHE markedly attenuated the overexpression of nuclear factor-κB in gastric mucosa of mice. It was concluded that CHE represents a potential therapeutic option to reduce the risk of gastric ulceration. In addition, acute toxicity study revealed no abnormal sign to the mice treated with CHE (15mg/kg). These findings suggest that the gastroprotective activity of CHE might contribute in adjusting the inflammatory cytokine by regulating the NF-κB signalling pathway.

Journal Article

Abstract  The communication reports the synthesis, characterization, and magnetic behavior of a novel μ4-carbonato supported and imidazole capped ligated nickel cage [Ni8(μ-H2bpmp)4(μ4-CO3)4(ImH)8](NO3)4·2H2O (1) through self-assembly of ligand bound ferromagnetic Ni2 building blocks. Structural analysis indicates newer geometrical features for the coordination cage formation and dominant interdimer antiferromagnetic coupling resulting in a diamagnetic ground state.

Journal Article

Abstract  BACKGROUND: The mechanisms of chronic cough are unclear. Many reactive oxygen species affect airway sensory C-fibres which are capable to induce cough. Several chronic lung diseases are characterised by cough and oxidative stress. In asthma, an association between the cough severity and airway oxidative stress has been demonstrated. The present study was conducted to investigate whether airway oxidative stress is associated with chronic cough in subjects without chronic lung diseases.

METHODS: Exhaled breath condensate samples were obtained in 43 non-smoking patients with chronic cough and 15 healthy subjects. Exclusion criteria included a doctor's diagnosis of any lung disorders and any abnormality in lung x-ray. The concentration of 8-isoprostane was measured. In addition, the patients filled in Leicester Cough Questionnaire and underwent hypertonic saline cough provocation test, spirometry, ambulatory peak flow monitoring, nitric oxide measurement, and histamine airway challenge. In a subgroup of patients the measurements were repeated during 12 weeks' treatment with inhaled budesonide, 800 ug/day.

RESULTS: The 8-isoprostane concentrations were higher in the cough patients than in the healthy subjects (24.6 ± 1.2 pg/ml vs. 10.1 ± 1.7 pg/ml, p = 0.045). The 8-isoprostane concentration was associated with the Leicester Cough Questionnaire total score (p = 0.044) but not with the cough sensitivity to saline or other tests. Budesonide treatment did not affect the 8-isoprostane concentrations.

CONCLUSIONS: Chronic cough seems to be associated with airway oxidative stress in subjects with chronic cough but without chronic lung diseases. This finding may help to develop novel antitussive drugs.

TRIAL REGISTRATION: The study was registered in ClinicalTrials.gov database (KUH5801112), identifier NCT00859274.

Journal Article

Abstract  Kinetics of CH2OO Criegee intermediate reactions with SO2, NO2, NO, H2O and CH3CHO and CH2I radical reactions with NO2 are reported as a function of pressure at 295 K. Measurements were made under pseudo-first-order conditions using flash photolysis of CH2I2-O2-N2 gas mixtures in the presence of excess co-reagent combined with monitoring of HCHO reaction products by laser-induced fluorescence (LIF) spectroscopy and, for the reaction with SO2, direct detection of CH2OO by photoionisation mass spectrometry (PIMS). Rate coefficients for CH2OO + SO2 and CH2OO + NO2 are independent of pressure in the ranges studied and are (3.42 ± 0.42) × 10(-11) cm(3) s(-1) (measured between 1.5 and 450 Torr) and (1.5 ± 0.5) × 10(-12) cm(3) s(-1) (measured between 25 and 300 Torr), respectively. The rate coefficient for CH2OO + CH3CHO is pressure dependent, with the yield of HCHO decreasing with increasing pressure. Upper limits of 2 × 10(-13) cm(3) s(-1) and 9 × 10(-17) cm(3) s(-1) are placed on the rate coefficients for CH2OO + NO and CH2OO + H2O, respectively. The upper limit for the rate coefficient for CH2OO + H2O is significantly lower than has been reported previously, with consequences for modelling of atmospheric impacts of CH2OO chemistry.

Journal Article

Abstract  In this issue of the Journal, Villeneuve et al. (Am J Epidemiol. 2014;179(4):443-451) present epidemiologic evidence supporting the literature on the adverse effects of air pollution on risk of lung cancer. They found that ambient exposure to volatile organic compounds, especially when measured at longer time scales, was associated with increased odds of lung cancer in citizens of Toronto, Ontario, Canada, between 1997 and 2002. Specifically, in fully adjusted models, they observed that an interquartile-range increase in benzene concentration was associated with an odds ratio of 1.51 (95% confidence interval: 1.13, 2.01) using exposure at the time of interview. The odds ratio increased to 1.84 (95% confidence interval: 1.26, 2.68) when time-weighted exposure at all previous addresses was considered. They obtained similar results for exposure to nitrogen dioxide. These findings add weight to the substantial (and rapidly growing) body of literature on the relation of air pollution with lung cancer risk, as well as illustrate important aspects of the effects of different exposure assessment choices and potential sources of key interest.

Journal Article

Abstract  Pothos scandens L. was used in Indian traditional medicine as an antiasthmatic drug. The ethanolic and aqueous extracts were prepared with aerial parts of P. scandens (PSE & PSA). ESI MS/MS of PSE ethanolic extract was carried out for the determination of chemical constituents. CP1 is isolated from the PSE, structurally confirmed with NMR and LCMS/MS. PSE, PSA and CP1 are evaluated against ovalbumin (OVA) induced airway hyperresponsiveness (AHR) in balb/c mice. The test drugs are administered p.o. prior to challenge with aerosolized 2.5% w/v OVA. Total and differential leucocyte count, nitrite (NO2), nitrate (NO3), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-13 (IL-13) are estimated in bronchoalveolar lavage fluid (BALF). Similarly, myeloperoxidase (MPO), malonaldehyde (MDA) and total lung protein (TLP) are estimated in the lungs. The results reveal a significant increase in total and differential leucocyte count, NO2, NO3, TNF-α, IL-6, and IL-13 in OVA induced AHR. However, these parameters are significantly decreased in PSE and PSA tested doses (PSE 100 & 200mg/kg). While, treatment with CP1 is less effective at 5 & 10mg/kg doses. Similar observations obtain for MPO and MDA in lungs. However, the mean value indicated that the PSE at 200mg/kg showed a significant restoration in all the parameters. Pro-inflammatory mediators are known to be responsible for AHR. Histopathology revealed justifies the effectiveness. The present investigations suggest PSE are interesting molecules for further research for asthma, with an approach through pro-inflammatory inhibitory pathway. P. scandens is a potential herbal medicine for allergy induced asthma.

Journal Article

Abstract  Measuring fractional exhaled nitric oxide (FeNO) is a relatively new option for assessing allergic inflammation in the lungs. Clinical management of asthma is challenging, and measuring exhaled nitric oxide can provide another type of data to assist in meeting this challenge. FeNO is easy to perform, and the equipment is not forbiddingly expensive. FeNO provides a complement to traditional measures of asthma control and can help guide diagnostic and treatment choices. This article explains what it is, how the measurements are performed, what the norms are, and its use and limitations in the management of asthma.

Journal Article

Abstract  Rats reared in hyperoxia exhibit a sustained (vs. biphasic) hypoxic ventilatory response (HVR) at an earlier age than untreated, Control rats. Given the similarity between the sustained HVR obtained after chronic exposure to developmental hyperoxia and the mature HVR, it was hypothesized that hyperoxia-induced plasticity and normal maturation share common mechanisms such as enhanced glutamate and nitric oxide signaling and diminished platelet-derived growth factor (PDGF) signaling. Rats reared in 21% O2 (Control) or 60% O2 (Hyperoxia) from birth until 4-5 days of age were studied after intraperitoneal injection of drugs targeting these pathways. Hyperoxia rats receiving saline showed a sustained HVR to 12% O2, but blockade of NMDA glutamate receptors (MK-801) restored the biphasic HVR typical of newborn rats. Blockade of PDGF-β receptors (imatinib) had no effect on the pattern of the HVR in Hyperoxia rats, although it attenuated ventilatory depression during the late phase of the HVR in Control rats. Neither nitric oxide synthase inhibitor used in this study (nNOS inhibitor I and l-NAME) altered the pattern of the HVR in Control or Hyperoxia rats. Drug-induced changes in the biphasic HVR were not correlated with changes in metabolic rate. Collectively, these results suggest that developmental hyperoxia hastens the transition from a biphasic to sustained HVR by upregulating glutamate-dependent mechanisms and downregulating PDGF-dependent mechanisms, similar to the changes underlying normal postnatal maturation of the biphasic HVR.

Journal Article

Abstract  The new one-dimensional coordination framework (Zn(DMF)NO3)2(NDC)(DPMNI), where NDC = 2,6-naphthalenedicarboxylate and DPMNI = N,N'-bis(4-pyridylmethyl)-1,4,5,8-naphthalenetetracarboxydiimide, which has been crystallographically characterized, exhibits two redox-accessible states due to the successive reduction of the naphthalenediimide (NDI) ligand core. Solid-state electrochemical and vis-near-IR spectroelectrochemical measurements coupled with density functional theory (DFT) calculations enabled the origins of the optical transitions in the spectra of the monoradical anion and dianion states of the material to be assigned. Electron paramagnetic resonance (EPR) spectroscopy revealed that the paramagnetic radical anion state of the DPMNI core could be accessed upon broad-spectrum white light irradiation of the material, revealing a long-lived excited state, possibly stabilized by charge delocalization which arises from extensive π-π* stacking interactions between alternating NDC and NDI aromatic cores which are separated by a distance of 3.580(2) Å.

Journal Article

Abstract  A summer episode was modeled to address the expected response of ambient air O3 to hypothetical emission control scenarios in northeastern Mexico, and in particular in the Monterrey Metropolitan Area (MMA). This region is of interest because the MMA holds one of the worst air quality problems in the country and levels of air pollutants in the rest of northeastern Mexico are starting to be a concern. The MM5-SMOKE-CMAQ platform was used to conduct the numerical experiments. Twenty-four control scenarios were evaluated, combining the level of emission controls of O3 precursors (NO(x) and volatile organic compounds [VOCs]) from 0% to 50%. For the MMA, VOC-only controls result in the best option to reduce O3 concentrations, though the benefit is limited to the urban core. This same strategy results in negligible benefits for the rest of northeastern Mexico. NO(x) controls result in an increase in O3 concentration within the MMA of up to 20 ppbv and a decrease at downwind locations of up to 11 ppbv, with respect to the base-case scenario. Indicator ratios were also used to probe for NO(x)-sensitive and VOC-sensitive areas. Locations with an important influence of NO(x) point sources (i.e., Monclova and Nava/Acuña) are quite sensitive to changes in NO(x) emissions. Border cities in the Rio Bravo/Grande Valley tend to be marginally NO(x)-sensitive. Overall, the MMA seems to be dominated by a VOC-sensitive regime, while the rest of the region would tend to have a NO(x)-sensitive response. The results obtained serve to expand the current knowledge on the chemical regimes that dominate this region (VOC- or NO(x)-sensitive), and thus could help guide public policies related to emission regional control strategies.

Journal Article

Abstract  Hybrid technology offers an attractive option for transit buses, since it has the potential to significantly reduce operating costs for transit agencies. The main impetus behind use of hybrid transit vehicles is fuel savings and reduced emissions. Laboratory tests have indicated that hybrid transit buses can have significantly lower emissions compared with conventional transit buses. However the number of studies is limited and laboratory tests may not represent actual driving conditions, since in-use vehicle operation differs from laboratory test cycles. This paper describes an on-road evaluation of in-use emission differences between hybrid-electric and conventional transit buses for the Ames, Iowa transit authority, CyRide. Emissions were collected on-road using a portable emissions monitoring system (PEMS) for three hybrid and two control buses. Emissions were collected for at least one operating bus day. Each bus was evaluated over the same route pattern, which utilizes the same driver. The number of passengers embarking or disembarking at each stop was collected by an on-board data collector so that passenger load could be included. Vehicle emissions are correlated to engine load demand, which is a function of factors such as vehicle load, speed, and acceleration. PEMS data are provided second by second and vehicle-specific power (VSP) was calculated for each row of data. Instantaneous data were stratified into the defined VSP bins and then average modal emission rates and standard errors were calculated for each bus for each pollutant. Pollutants were then compared by bus type. Carbon dioxide, carbon monoxide, and hydrocarbon emissions were higher for the regular buses across most VSP bins than for the hybrid buses. Nitrogen oxide emissions were unexpectedly higher for the hybrid buses than for the control buses.

Journal Article

Abstract  Macrophages are among the first cellular actors facing the invasion of microorganisms. These cells are able to internalize pathogens and destroy them by means of toxic mediators, many of which are produced enzymatically and have strong oxidizing capacity. Indeed, macrophages count on the NADPH oxidase complex activity, which is triggered during pathogen invasion and leads to the production of superoxide radical inside the phagosome. At the same time, the induction of nitric oxide synthase results in the production of nitric oxide in the cytosol which is able to readily diffuse to the phagocytic vacuole. Superoxide radical and nitric oxide react at diffusion controlled rates with each other inside the phagosome to yield peroxynitrite, a powerful oxidant capable to kill micro-organisms. Peroxynitrite toxicity resides on oxidations and nitrations of biomolecules in the target cell. The central role of peroxynitrite as a key effector molecule in the control of infections has been proven in a wide number of models. However, some microorganisms and virulent strains adapt to survive inside the potentially hostile oxidizing microenvironment of the phagosome by either impeding peroxynitrite formation or rapidly detoxifying it once formed. In this context, the outcome of the infection process is a result of the interplay between the macrophage-derived oxidizing cytotoxins such as peroxynitrite and the antioxidant defense machinery of the invading pathogens. © 2013 BioFactors, 2013.

Journal Article

Abstract  OBJECTIVES: We investigated the role of inducible nitric oxide synthase (iNOS) in the pathogenesis of sinonasal polyps.

METHODS: Adult patients (21 men, 3 women) with nasal polyposis underwent functional endoscopic sinus surgery. Nine adults without polyps (6 men) who underwent septoplasty and/or rhinoplasty served as controls. Polyp specimens came from three regions: the maxillary sinus (10), ethmoid sinus (14), and nasal cavity (10). Control group samples (9) came from the inferior turbinate. Specimens were evaluated in eight mucosal layers for count and distribution of inflammatory cells and iNOS expression. An iNOS positivity index (PI) was determined for the epithelium (E), subepithelial layer of the lamina propria (SE), and deep paraglandular layer of the mucosa (D).

RESULTS: Polymorphonuclear cell (PMNC) % values of the ethmoid and maxillary sinus and overall ethmoid sinus PI were significantly higher in the polyp group. Patients with longer polyp duration, D-perivascular (D-pv), and a higher Brinkmann index had decreased ethmoid sinus D PIs. However, in older patients and patients with longer polyp duration, perivascular PIs increased in maxillary sinus SE and D, respectively. Furthermore, as PMNC % and iNOS-PMNC PI increased, SE_glandular and epithelial_apical iNOS values decreased. In the ethmoid and maxillary sinuses, iNOS_D_. endothelial values increased but decreased in the nasal cavity.

CONCLUSIONS: iNOS may play a role in sinonasal polyp pathogenesis, especially in mucosal SE and D layers. Increased vascular permeability, stromal edema, inflammatory cell migration into the stroma of the mucosa, and increased mucosal gland secretion may result in polyp formation.

Journal Article

Abstract  A highly selective chemosensor 1 based on an acylhydrazone group as binding site and naphthalene group as the fluorescence signal group were described, which could instantly detect CN(-) in water with specific selectivity and high sensitivity. The detection of cyanide was performed via the nucleophilic attack of cyanide anion on the carbonyl group, which could be confirmed by (1)H NMR, (13)C NMR, ESI-MS and DFT calculations. The addition of CN(-) to sensor 1 induced a remarkable color change from colorless to yellow and generated a blue fluorescence, these sense procedure could not interfered by other coexistent competitive anions (F(-), Cl(-), Br(-), I(-), AcO(-), H2PO4(-), HSO4(-), ClO4(-), SCN(-), S(2-), NO3(-) and SO4(2-)). The detection limits were 5.0×10(-7) M and 2.0×10(-9) M of CN(-) using the visual fluorescent color changes and fluorescence spectra changes respectively, which is far lower than the WHO guideline of 1.9×10(-6) M. Test strips based on sensor 1 were fabricated, which could act as a convenient and efficient CN(-) test kit to detect CN(-) in pure water for "in-the-field" measurement.

Journal Article

Abstract  The dorsal hippocampus (DH) is a structure of the limbic system that is involved in emotional, learning and memory processes. There is evidence indicating that the DH modulates cardiovascular correlates of behavioral responses to stressful stimuli. Acute restraint stress (RS) is an unavoidable stress situation that evokes marked and sustained autonomic changes, which are characterized by elevated blood pressure (BP), intense heart rate (HR) increase and a decrease in cutaneous temperature. In the present study, we investigated the involvement of an N-methyl-D-aspartate (NMDA) glutamate receptor/nitric oxide (NO) pathway of the DH in the modulation of autonomic (arterial BP, HR and tail skin temperature) responses evoked by RS in rats. Bilateral microinjection of the NMDA receptor antagonist AP-7 (10 nmol/500 nL) into the DH attenuated RS-evoked autonomic responses. Moreover, RS evoked an increase in the content of NO₂/NO₃ in the DH, which are products of the spontaneous oxidation of NO under physiological conditions that can provide an indirect measurement of NO production. Bilateral microinjection of N-propyl-L-arginine (0.1 nmol/500 nL; N-propyl, a neuronal NO synthase (nNOS) inhibitor) or carboxy-PTIO (2 nmol/500 nL; c-PTIO, an NO scavenger) into the DH also attenuated autonomic responses evoked by RS. Therefore, our findings suggest that a glutamatergic system present in the DH is involved in the autonomic modulation during RS, acting via NMDA receptors and nNOS activation. Furthermore, the present results suggest that NMDA receptor/nNO activation has a facilitatory influence on RS-evoked autonomic responses.

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