African-American inflammatory bowel disease in a Southern U.S. health center

<p>Abstract</p> <p>Background</p> <p>Inflammatory Bowel Diseases (IBD) remain significant health problems in the US and worldwide. IBD is most often associated with eastern European ancestry, and is less frequently reported in other populations of African origin e.g. African Americans ('AAs'). Whether AAs represent an important population with IBD in the US remains unclear since few studies have investigated IBD in communities with a majority representation of AA patients. The Louisiana State University Health Sciences Center in Shreveport (LSUHSC-S) is a tertiary care medical center, with a patient base composed of 58% AA and 39% Caucasian (W), ideal for evaluating racial (AA vs. W) as well and gender (M vs. F) influences on IBD.</p> <p>Methods</p> <p>In this retrospective study, we evaluated 951 visits to LSUHSC-S for IBD (between 2000 to 2008) using non-identified patient information based on ICD-9 medical record coding (Crohn's disease 'CD'-555.0- 555.9 and ulcerative colitis 'UC'-556.0-556.9).</p> <p>Results</p> <p>Overall, there were more cases of CD seen than UC. UC and CD affected similar ratios of AA and Caucasian males (M) and females (F) with a rank order of WF > WM > AAF > AAM. Interestingly, in CD, we found that annual visits per person was the highest in AA M (10.7 ± 1.7); significantly higher (* -p < 0.05) than in WM (6.3 ± 1.0). Further, in CD, the female to male (F: M) ratio in AA was significantly higher (*- p < 0.05) (1.9 ± 0.2) than in Caucasians (F:M = 1.3 ± 0.1) suggesting a female dominance in AACD; no differences were seen in UC F: M ratios.</p> <p>Conclusion</p> <p>Although Caucasians still represent the greatest fraction of IBD (~64%), AAs with IBD made up >1/3 (36.4%) of annual IBD cases from 2000-2008 at LSUHSC-S. Further studies on genetic and environments risks for IBD risk in AAs are needed to understand differences in presentation and progression in AAs and other 'non-traditional' populations.</p

Spectral gamma ray logging: A cost-effective method for uranium exploration

The most useful technique in uranium exploration program is undoubtedly radiometric surveys. This is due to the fact that uranium emits gamma rays ranging from as low as 47kev to 2.2Mev, which can be detected and quantified using suitable radiation detector. Combination of aerial radiometric surveys, ground examination of the detected anomalies, followed by drilling and gamma ray logging of drilled boreholes has resulted in the identification of large uranium resources. Borehole logging provides the most important subsurface information required for the uranium exploration program. An area known to contain only uranium, computed gamma ray logging with a Geiger Muller (GM) Detector rapidly gives the required subsurface radioactivity information whereas, in a heterogeneously mineralized area of uranium with thorium, logging data using GM detector may mislead to wrong interpretation. Under such condition, using the principle of gamma ray spectrometry, scintillation detector-based spectral gamma ray logging is carried out. Identifying uranium in the presence of thorium is a complex process and this paper deals with a case study on the spectral gamma ray logging carried out to locate the subsurface uraniferous zone in Pakkanadu area, Salem district of Tamil nadu, where the surface anomaly indicated the presence of high thorium content. The various limitations such as small detector size, large sample volume, high-correction factor required for quantifying the individual elements, and the study carried out for optimizing the time required for data acquisition are discussed

Biohythane as an energy feedstock for solid oxide fuel cells

Biogas (60%-CH4, 40%- CO2) is a potential source of renewable energy when used as energy feedstock for solid oxide fuel cells (SOFC), but releases biogenic CO2 emissions. Hybrid SOFC performance can be affected by fuel composition and reformer performance. Biohythane (58%-CH4, 35%-CO2 and 7% H2) can be a better alternative providing balance between energy and biogenic emissions. Biohythane performance is studied for a 120 kW SOFC stack using ASPEN process model and compared with other feed stocks. This work is the first to study and report on the application of biohythane in SOFC systems. Biohythane was found to produce less biogenic CO2 emissions and 6% less CO at the reformer than biogas. Comparisons show that biohythane provides better efficiencies in hybrid SOFC systems. Sensitivity studies recommends operation of stack with biohythane at Steam to Carbon Ratio (STCR) = 2.0, i = 200 mA cm−2 and UF = 0.85 respectively

Hydrodynamic study of fluid catalytic cracker unit stripper

This paper reports a three-dimensional (3D) computational fluid dynamics (CFD) simulation of a laboratory scale fluid catalytic cracking unit (FCCU) stripper. Solid holdup and solid mixing were studied in a geometrically and dynamically scaled down cold model FCCU stripper fitted with disk and donut baffles. The solid holdup was measured using a gamma-ray densitometry technique with a 3 micro-Ci strength 137Cs radioactive source. Measurements were taken at different axial levels, for different chordal positions. An Eulerian-Eulerian approach was used to simulate the gas-solid flow in the stripper column. The CFD simulations predicted asymmetric solid holdup profiles emphasizing the importance of 3D simulations. The CFD model predictions matched well with the solid holdup data from experiments. The CFD model also clearly predicted the recirculation and dead zones as noticed in the experimental analysis. Local defluidization zones were also noticed near the donut baffle wall regions. The particle axial velocity was low near the baffle walls, indicating that the particles slide down on the baffle walls. The radial and axial variations of solid holdup are discussed in this work, giving new knowledge in the complex countercurrent operation. This work is first of its kind to report detailed 3D study on the hydrodynamics of stripper operation both in cold flow and in the CFD model

Hydrodynamics of a Fluid Catalytic Cracking Stripper Using γ-ray Densitometry

This paper reports hydrodynamics of a laboratory-scale fluid catalytic cracking (FCC) stripper. The laboratory-scale stripper was designed by geometrically and dynamically scaling down an industrial-scale FCC stripper that had a disk and donut baffle. The solids holdup was measured using a γ-ray densitometry technique with a 3-μCi-strength Cs-137 radioactive source. Measurements were taken at different elevations and chordal positions. The effect of operating conditions on the solids holdup profiles was investigated in detail. For example, the particle flow rate was varied from 0.025 kg/s to 0.042 kg/s, and the superficial air velocity between 0.74 m/s and 1.1 m/s. It was observed that the shape of baffles played an important role in the hydrodynamics of the stripper. Several dead zones were noticed under the baffle regions indicating unused areas in the stripper. The measured solid holdup radial profiles were of asymmetric nature underlying the need for three-dimensional (3D) simulations. At low superficial gas velocities, there was a widespread segregation in the solid phase, which along with the solid holdup decreased on increasing the air superficial velocity. However, the change in solid flow rates did not have any effect on the solids holdup

Slow pyrolysis of biosolids in a bubbling fluidised bed reactor using biochar, activated char and lime

Slow pyrolysis of biosolids was investigated employing a laboratory scale fluidised bed reactor maintaining the bubbling mode of fluidisation where the primary product was biochar. Low cost bed materials such as natural lime, biosolids derived biochar and activated char of biosolids origin were employed in the investigation. The pyrolysis experiments were mainly conducted in a batch mode at a constant heating rate of 35 °C/min, a solids residence time of 60 min and a biosolids to bed material ratio of 1. Experiments were conducted by varying pyrolysis temperatures (500, 700 and 900 °C) and bed material. The product characterisation was performed employing various analytical instruments including Scanning Electron Microscope (SEM), Fourier-Transform Infrared (FTIR) spectrometer, Gas ChromatographyMass Spectrometry (GC/MS) and BrunauerEmmettTeller (BET) analyser. The objectives of this work were to identify the most suitable bed material and optimum operating temperature for generating biochar of superior quality as well as cracking down unwanted nitrogenated, oxygenated, polycyclic aromatic compounds (PACs) and aliphatic compounds as these species are difficult to combust or have the potential to cause secondary emissions. The temperature between 700 and 900 °C as well as biochar and activated char as bed materials were found to be favourable in obtaining biochar of high porosity and high surface area and in reducing nitrogenated, oxygenated, PACs and aliphatic compounds