Impact of multiscale dynamical processes and mixing on the chemical composition of the upper troposphere and lower stratosphere during the Intercontinental Chemical Transport Experiment–North America

We use high-frequency in situ observations made from the DC8 to examine fine-scale tracer structure and correlations observed in the upper troposphere and lower stratosphere during INTEX-NA. Two flights of the NASA DC-8 are compared and contrasted. Chemical data from the DC-8 flight on 18 July show evidence for interleaving and mixing of polluted and stratospheric air masses in the vicinity of the subtropical jet in the upper troposphere, while on 2 August the DC-8 flew through a polluted upper troposphere and a lowermost stratosphere that showed evidence of an intrusion of polluted air. We compare data from both flights with RAQMS 3-D global meteorological and chemical model fields to establish dynamical context and to diagnose processes regulating the degree of mixing on each day. We also use trajectory mapping of the model fields to show that filamentary structure due to upstream strain deformation contributes to tracer variability observed in the upper troposphere. An Eulerian measure of strain versus rotation in the large-scale flow is found useful in predicting filamentary structure in the vicinity of the jet. Higher-frequency (6–24 km) tracer variability is attributed to buoyancy wave oscillations in the vicinity of the jet, whose turbulent dissipation leads to efficient mixing across tracer gradients

Optimum Location and Angle of Inclination of Cut-off to Control Exit Gradient and Uplift Pressure Head under Hydraulic Structures

The work reported in this research presents numerical investigations on the effect of cut-off inclination angle on exit gradient and uplift pressure head under hydraulic structure and determines the optimum location and angle of inclination of cut-off. This problem is solved using the finite element method by using (ANSYS 11.0). It is concluded that using downstream cut-off inclined towards the downstream side with Ө less than 120º is beneficial in increasing the safety factor against the piping phenomenon. The results are evaluated graphically in non-dimensional form

Effect of Fuel on the Structural and Optical Properties of MgO Nanoparticles Prepared by Auto–Combustion of Sol-Gel Method

Magnesium nitrate as precursor and citric acid as fuel are used as a starting material for the preparation  magnesium oxide (MgO) nanoparticles via sol- gel of auto–combustion  method.  X-ray diffraction patterns indicate that the obtain (MgO) nanoparticles are in good crystallinity and show that the all grain size was decreases with increasing of concentration citric acid as fuel. The crystallite size was calculated using Scherrer and Williamson-Hall formula at difference ratios of fuel which have maximum crystallite size (13.55 nm) and  (14.26 nm) respectively. The SEM images for MgO powder prepared with fuel (Citric acid) at three various molar ratios show the morphology of the oxides is mostly spherical with some agglomeration. The optical properties  show that  the transmittance decrease with increase the fuel amount and  additives ammonia and fuel played an important role in the combustion. Keywords: MgO , Nanoparticles , Sol-Gel, Auto–Combustion, Structural , Optica

The optimum condition for the synthesis of carbon nanofibers on activated carbon to remove lead from aqueous solution

Optimum process condition for the production of Carbon Nanofibers (CNFs) to remove lead ion (Pb) from aqueous solution is reported here. The CNFs were produced on the catalyst (Ni2+) impregnated palm oil-based cheap Powder Activated Carbon (PAC). Locally fabricated Chemical Vapour Deposition (CVD) system was used while acetylene (C2H2) was the carbon source. The porous nano-composite product is named “PAC-CNFs”, which was synthesized through a process using impregnated oil palm shell based PAC as a solid substrate. Design Expert 6.0.8 software was used to design the experimental plan and to determine the optimized process parameters for the growth of CNFs by using sorption capacity for Pb2+ by the PAC-CNFs adsorbent, as a response. The effect of different factors on the growth of CNFs including the temperature of CNFs growth (550 to 750 °C), time of growth (30 to 60 min), and the ratio of input C2H2/H2 gases (0.25 to 1.0) was evaluated. The predicted values for the sorption capacity of Pb2+ by the PAC-CNFs were in close agreement with the experimental data (R2 = 0.99). The optimal process condition: temperature for the growth of CNFs, time, and C2H2/H2 ratio was determined as 637 °C, 30 min, and 1.0, respectively. The CNFs grown under the optimized condition exhibited sorption capacity of 77 mg/g in removing Pb2+ from synthetic wastewater containing lead (Pb2+) ion

Synthesis and spectrometric study of some nucleophilic reactions of the antiepileptic molecule; 5,5-diphenyl imidazolidine-2,4-dione.

New reaction routs were performed for the compound 5,5-diphenyl 2,4-imidazolidinedione (I) to give derivatives (II – VII). These reactions include acylation, halogenation, reduction, and nucleophilic substitutions. Most of the derivatives showed variable chemical reactivities and thermal stability, and the N1 and N3 disubstituted analogue were found much less stable, and hydrolyzes easily in the reaction medium. According to 1H and 13C NMR measurement's, 1,3-Dichloro-5,5-diphenyl imidazolidine-2,4-dione (V) was found to chlorinate the methyl group of the solvent DMSO-d6. Sodium hydroxide consumption analysis was established to reveal the molecularity against NaOH, by following acid-base volumetric method

Comparative analysis of the clinical characteristics and outcomes of patients with Wilms tumor in the United Kingdom and Japan

BACKGROUND: Wilms tumor (WT) demonstrates epidemiological differences by world region and ethnicity. To enhance understanding of these differences, we retrospectively analyzed clinical trial data sets from the UK and Japan over a 20-year period. PROCEDURE: We used data from three consecutive clinical trials in the UK and a single study in Japan that enrolled patients diagnosed during 1996-2015, to compare clinical characteristics and outcomes between countries. RESULTS: During 1996-2015, 1395 patients in the UK and 537 in Japan were included. Japanese patients have a significantly younger median age at diagnosis than those in the UK (28 months vs 39 months). The proportion of patients with stage IV, large tumors, and anaplastic histology appears to be higher in the UK than in Japan (18% vs 11%, 62% vs 49%, 8% vs 3%, respectively). During 2005-2015, 77 hospitals treated WT in Japan compared with only 20 hospitals in the UK. Five-year overall survival of patients with WT was over 90% in both countries, but five-year event-free survival of patients with stage IV was significantly lower in Japan than in the UK (50.0% vs 76.2%, P = 0.001). CONCLUSIONS: Differences in age of onset, tumor size at diagnosis, and histology may reflect differences in the genetic background of patients with WT between countries, but population-based phenotype-genotype data are lacking. The difference in survival probability for stage IV patients may be due to different diagnostic criteria or different treatment strategies. Prospective, international clinical studies including genomic analyses are needed to confirm these findings and improve clinical practice

Prognostic significance of histopathological response to preoperative chemotherapy in unilateral Wilms' tumor: An analysis of 899 patients treated on the SIOP WT 2001 protocol in the UK-CCLG and GPOH studies

In the SIOP Wilms' tumor (WT) studies, preoperative chemotherapy is used as primary treatment, and tumors are classified thereafter by pathologists. Completely necrotic WTs (CN-WTs) are classified as low-risk tumors. The aim of the study was to evaluate whether a subset of regressive type WTs (RT-WTs) (67%-99% chemotherapy-induced changes [CIC]) showing an exceptionally good response to preoperative chemotherapy had comparably excellent survivals as CN-WTs, and to establish a cut-off point of CIC that could define this subset. The study included 2117 patients with unilateral, nonanaplastic WTs from the UK-CCLG and GPOH-WT studies (2001-2020) treated according to the SIOP-WT-2001 protocol. There were 126 patients with CN-WTs and 773 with RT-WTs, stages I-IV. RT-WTs were subdivided into subtotally necrotic WTs (>95% CIC) (STN-WT96-99) (124 patients) and the remaining of RT-WT (RR-WT67-95) (649 patients). The 5-year event-free survival (EFS) and overall survival (OS) for CN-WTs were 95.3% (±2.1% SE) and 97.3% (±1.5% SE), and for RT-WTs 85.7% (±1.14% SE, P < .01) and 95.2% (±0.01% SE, P = .59), respectively. CN-WT and STN-WT96-99 groups showed significantly better EFS than RR-WT67-95 (P = .003 and P = .02, respectively), which remained significantly superior when adjusted for age, local stage and metastasis at diagnosis, in multivariate analysis, whereas OS were superimposable (97.3 ± 1.5% SE for CN-WT; 97.8 ± 1.5% SE for STN-WT96-99; 94.7 ± 1.0% SE for RR-WT67-95). Patients with STN-WT96-99 share the same excellent EFS and OS as patients with CN-WTs, and although this was achieved by more treatment for patients with STN-WT96-99 than for patients with CN-WT, reduction in postoperative treatment of these patients may be justified

4a-Methyl-2,3,4,4a-tetra­hydro-1H-carbazole-6-sulfonamide

In the title mol­ecule, C13H16N2O2S, the nine non-H atoms comprising the indole residue are approximately coplanar (r.m.s. deviation = 0.031 Å). The partially saturated ring adopts a chair conformation. One amine H forms an inter­molecular N—H⋯O hydrogen bond to a sulfonamide O atom, while the other amine H form is connected to the indole N atom of an adjacent mol­ecule via an N—H⋯N hydrogen bond, resulting in a three-dimensional architecture

3-Amino-1-(4-meth­oxy­phen­yl)-9,10-dihydro­phenanthrene-2,4-dicarbonitrile

In the title compound, C23H17N3O, significant deviations from planarity are evidenced. This is quanti­fied in the dihedral angles formed between the central amino-benzene ring and the benzene rings of the meth­oxy­benzene [67.93 (8)°] and 1,2-dihydro­naphthalene [28.27 (8)°] residues. In the crystal the amino-H atoms form hydrogen bonds to the meth­oxy-O atom and to one of the cyano-N atoms to generate a two-dimensional array with a zigzag topology that stacks along the ( 1) plane

Characteristics of tropospheric ozone depletion events in the Arctic spring: analysis of the ARCTAS, ARCPAC, and ARCIONS measurements and satellite BrO observations

Arctic ozone depletion events (ODEs) are caused by halogen catalyzed ozone loss. In situ chemistry, advection of ozone-poor air mass, and vertical mixing in the lower troposphere are important factors affecting ODEs. To better characterize the ODEs, we analyze the combined set of surface, ozonesonde, and aircraft in situ measurements of ozone and bromine compounds during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC), and the Arctic Intensive Ozonesonde Network Study (ARCIONS) experiments (April 2008). Tropospheric BrO columns retrieved from satellite measurements and back trajectory calculations are also used to investigate the characteristics of observed ODEs. In situ observations from these field experiments are inadequate to validate tropospheric BrO columns derived from satellite measurements. In view of this difficulty, we construct an ensemble of tropospheric column BrO estimates from two satellite (OMI and GOME-2) measurements and with three independent methods of calculating stratospheric BrO columns. Furthermore, we select analysis methods that do not depend on the absolute magnitude of column BrO, such as time-lagged correlation analysis of ozone and tropospheric column BrO, to understand characteristics of ODEs. Time-lagged correlation analysis between in situ (surface and ozonesonde) measurements of ozone and satellite derived tropospheric BrO columns indicates that the ODEs are due to either local halogen-driven ozone loss or short-range (∼1 day) transport from nearby regions with ozone depletion. The effect of in situ ozone loss is also evident in the diurnal variation difference between low (10th and 25th percentiles) and higher percentiles of surface ozone concentrations at Alert, Canada. Aircraft observations indicate low-ozone air mass transported from adjacent high-BrO regions. Correlation analyses of ozone with potential temperature and time-lagged tropospheric BrO column show that the vertical extent of local ozone loss is surprisingly deep (1–2 km) at Resolute and Churchill, Canada. The unstable boundary layer during ODEs at Churchill could potentially provide a source of free-tropospheric BrO through convective transport and explain the significant negative correlation between free-tropospheric ozone and tropospheric BrO column at this site