142 research outputs found
MODIFICATION AND PERFORMANCE OF DEVICE FOR TESTING THE DIESEL ENGINE INJECTOR
iesel engine, but most of it is operating manually, maintenance and repair centers mostly have used the manually device which depended on the hand of operator to operate it therefore there are inaccuracies in tests. The injector tester device was modified from manual operation to mechanical operation to achieve the uniformity of the injection pressure during the injector test, install of reading, save time and accuracy of testing. Injector tester before the modification was consisted of small fuel tank, pump, pressure gauge, handle pumping and connecting tube. The injector tester device after the modification was consisted of main frame, fuel tank, injection unit, power transmission and measuring table. From the experiments the fuel consumption was increased with injector tester device before modification than device after modification that with three different injectors due to the regularity of the motion in the mechanical device, but the manual device that is dependent on operator and the irregularity of motion which cause irregularity of pressure. Also, the fuel consumption was decreased with injectors' faults. This is indicating of accuracy reading pressure with the modified devices compared with the device before modified. The results indicated for the important factors which effect on the regularity of injection pressure during the injector testing. The injection pressure for modifying tester device was 175 bar and fuel consumption was 0.73 L/h. The injection pressure and fuel consumption for tester device before modification were 210 bar and 4.73 L/h respectively. The rate of reducing can be concluded by using the modified tester device for the injection pressure was 1:0.83 and for fuel consumption was 1:0.155 as compared with the manual tester
Methyl 2-{6-[(1-methoxy-1-oxopropan-2-yl)aminocarbonyl]pyridine-2-carboxamido}propanoate
In the title compound, C15H19N3O6, the amide planes are inclined at dihedral angles of 0.8 (6) and 12.1 (3)° with respect to the central pyridine ring. The mean planes of the corresponding methyl acetate groups form dihedral angles of 41.76 (13) and 86.48 (15)°, respectively with the mean plane of pyridine ring. A pair of weak intramolecular N—H⋯N hydrogen bonds generate an S(5)S(5) ring motif in the molecule. In the crystal, molecules are linked by N—H⋯O hydrogen bonds into [001] chains. The chains are cross-linked by C—H⋯O hydrogen bonds into layers lying parallel to bc plane. The crystal packing also features a C—H⋯π interaction
Neutrophil functions in late preterm neonates with respiratory distress syndrome
Background: Studies that have addressed the effects of respiratory distress syndrome (RDS) on neutrophil function suggested that neutrophil functions other than the generation of the respiratory burst are not impaired. Yet, results have been confusing and in some cases contradictory.Objectives: The aim of this cross-sectional controlled study is to assess neutrophil number and function in late preterm neonates with RDS.Methods: Thirty patients underwent clinical and laboratory evaluation including complete blood counts and tests of neutrophil functions (CD11b, CD62L and Dihydrorhodamine 123 by flowcytometry) in comparison to 15 healthy term controls. RDS was assessed clinically and radiologically (chest x-ray).Results: Fifty percent of patients (12 females and 18 males) had grade II respiratory distress followed by grade III then grade I. DHR, CD 11b and CD62L results were lower among the patients group (mean ± SD: 62.1± 12.23, 63.22 ± 11.41, 15.03 ± 8.7 respectively). There were no significant correlations between neutrophils count, DHR, CD11b and CD62L. Only CD11b was significantly lower with higher grades of RDS.Conclusion: Neonates with RDS show variable affection of neutrophil functions. Further studies are recommended to elucidate the exact mechanisms by which RDS can affect neutrophil functions and whether these effects are associated with increased incidence of infections.Keywords: Neutrophils, function, respiratory distress syndrome, late preterm, innate immunity, infections, adhesion molecule
Ethyl 2-amino-4-(4-fluorophenyl)-6-methoxy-4H-benzo[h]chromene-3-carboxylate
In the title compound, C23H20FNO4, the fluoro-substituted benzene ring is approximately perpendicular to the mean plane of the 4H-benzo[h]chromene ring system [maximum deviation = 0.264 (1) Å], with a dihedral angle of 83.79 (6)°. The pyran ring adopts a flattened boat conformation. The methoxy group is slightly twisted from the attached benzene ring of the 4H-benzo[h]chromene moiety [C—O—C—C = −2.1 (2)°]. An intramolecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked by N—H⋯O and N—H⋯F hydrogen bonds into a layer parallel to the bc plane. The crystal packing also features C—H⋯π interactions
On-Line Detection And Measurement Of Partial Discharge Signals In A Noisy Environment
In extracting partial discharge (PD) signals embedded in excessive noise, the need for an online and automated tool becomes a crucial necessity. One of the recent approaches that have gained some acceptance within the research arena is the Wavelet multi-resolution analysis (WMRA). However selecting an accurate mother wavelet, defining dynamic threshold values and identifying the resolution levels to be considered in the PD extraction from the noise are still challenging tasks. This paper proposes a novel wavelet-based technique for extracting PD signals embedded in high noise levels. The proposed technique enhances the WMRA by decomposing the noisy data into different resolution levels while sliding it into Kaiser's window. Only the maximum expansion coefficients at each resolution level are used in de-noising and measuring the extracted PD signal. A small set of coefficients is used in the monitoring process without assigning threshold values or performing signal reconstruction. The proposed monitoring technique has been applied to a laboratory data as well as to a simulated PD pulses embedded in a collected laboratory noise
Heterociklički derivati 3-(4-bromfenil) azo-5-fenil-2(3H)-furanona: Djelovanje na virus ptičje gripe (H5N1)
3-[2-(4-Bromphenyl)hydrazono]-5-phenyl-furan-2(3H)-one (1) was used for preparation of some novel pyrazole, pyridazinone, oxadiazole, triazole, thiazolidine and thioxo-pyrimidine derivatives. Some of the prepared products were tested for anti-avian influenza virus activity and revealed promising antiviral activity against H5N1 virus [A/Chicken/Egypt/1/20 % (H5N1)] by determination of both EC50 and LD50 and confirmed by plaque reduction assay on MDCK cells. Compounds 3-[2-(4-bromophenyl)hydrazono]-5-phenylfuran-2(3H)-one 1, 1-(4-bromophenyl)-N-hydroxy-5-phenyl-1H-pyrazole-3-carboxamide 5 and 1-(4-bromophenyl)-N-{2,3-dihydro-4-hydroxy-3-phenyl-6-oxo-2-thioxopyrimidin-1(6H)-yl}-5-phenyl-1H-pyrazole-3-carboxamide (12a) showed the highest effects. Detailed synthesis, spectroscopic data, and antiviral activity of the synthesized compounds are reported.3-[2-(4-Bromfenil)hidrazono]-5-fenil-furan-2(3H)-on (1) upotrjebljen je za pripravu novih derivata pirazola, piridazinona, oksadiazola, triazola, tiazolidina i tioksopirimidina. Neki od sintetiziranih spojeva imaju virustatski učinak na virus ptičje gripe H5N1. Farmakološki aktivnim spojevima određeni su EC50 i LD50 i dobiven je pozitivni test redukcije plaka na MDCK staničnoj liniji. Najjači učinak pokazali su 3-[2-(4-bromfenil)hidrazono]-5-fenilfuran-2(3H)-on (1), 1-(4-bromfenil)-N-hidroksi-5-fenil-1H-pirazol-3-karboksamid (5) i 1-(4-bromfenil)-N-{2,3-dihidro-4-hidroksi-3-fenil-6-okso-2-tioksopirimidin-1(6H)-il}-5-fenil-1H-pirazol-3-karboksamid (12a). Detaljno su opisani priprava, spektroskopski podaci i antivirusno djelovanje sintetiziranih spojeva
Methyl 2-({6-[(1-methoxy-2-methyl-1-oxopropan-2-yl)carbamoyl]pyridin-2-yl}formamido)-2-methylpropanoate
In the title compound, C17H23N3O6, the two methoxycarbonyl C—O—C=O planes are inclined at dihedral angles of 5.3 (4) and 83.9 (4)° with respect to the central pyridine ring. An intramolecular N—H⋯O hydrogen bond generates an S(5) ring motif. In the crystal, molecules are linked into a chain along the c axis via C—H⋯O hydrogen bonds
Serotonin 5-HT4 receptor boosts functional maturation of dendritic spines via RhoA-dependent control of F-actin
Activity-dependent remodeling of excitatory connections underpins memory formation in the brain. Serotonin receptors are known to contribute to such remodeling, yet the underlying molecular machinery remains poorly understood. Here, we employ high-resolution time-lapse FRET imaging in neuroblastoma cells and neuronal dendrites to establish that activation of serotonin receptor 5-HT4 (5-HT4R) rapidly triggers spatially-restricted RhoA activity and G13-mediated phosphorylation of cofilin, thus locally boosting the filamentous actin fraction. In neuroblastoma cells, this leads to cell rounding and neurite retraction. In hippocampal neurons in situ, 5-HT4R-mediated RhoA activation triggers maturation of dendritic spines. This is paralleled by RhoA-dependent, transient alterations in cell excitability, as reflected by increased spontaneous synaptic activity, apparent shunting of evoked synaptic responses, and enhanced long-term potentiation of excitatory transmission. The 5-HT4R/G13/RhoA signaling thus emerges as a previously unrecognized molecular pathway underpinning use-dependent functional remodeling of excitatory synaptic connections
A highly efficient green synthesis of 1, 8-dioxo-octahydroxanthenes
SmCl3 (20 mol%) has been used as an efficient catalyst for reaction between aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione at 120°C to give 1,8-dioxo-octahydroxanthene derivatives in high yield. The same reaction in water, at room temperature gave only the open chain analogue of 1,8-dioxo-octahydroxanthene. Use of eco-friendly green Lewis acid, readily available catalyst and easy isolation of the product makes this a convenient method for the synthesis of either of the products
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