This study provides a retrospective analysis of 60 patients who underwent thoracic reconstruction... more This study provides a retrospective analysis of 60 patients who underwent thoracic reconstruction with the omentum. Patients were identified by searching several databases to determine demographics, indications for surgery, operative technique, and postoperative course, including donor and recipient site morbidity. From January 1975 to May 2000, the authors harvested and transferred the omentum successfully (57 pedicled, 3 free) in 60 patients (mean age, 60 years; age range, 21-86 years) for sternal wound infections (N = 34), chest wall resections (N = 17), pectus deformities (N = 2), intrathoracic defects (N = 4), and breast reconstruction (N = 3). The omentum was used as a primary flap in 39 patients and as a salvage flap in 21 patients. Average operative time was 3.9 hours and average hospital stay was 34.3 days. Partial flap loss occurred in 7 patients, with no total flap failures. Morbidity included six abdominal wound infections and seven epigastric hernias. Mortality was 11.7%. The omentum can be harvested safely and used reliably to reconstruct varying thoracic wounds and defects. Specific indications from this series include osteoradionecrosis, chest wall tumors, massive sternal wounds, and refractory mediastinitis. Hultman CS, Culbertson JH, Jones GE, et al. Thoracic reconstruction with the omentum: indications, complications, and results.
ABSTRACT PURPOSE To study white matter (WM) properties in young children with autism spectrum dis... more ABSTRACT PURPOSE To study white matter (WM) properties in young children with autism spectrum disorder (ASD) and developmental delay (DD), we performed tissue-specific, smoothing-compensated (T-SPOON) analysis which is optimized for the voxel-based morphometry study. METHOD AND MATERIALS Thirty-one children with ASD (mean age: 5±1.7 years; 28 males), 11 children with DD (mean age: 4.4±1.7 years; 9 males), and 14 typically developing children (TD, mean age: 5.5±1.9 years; 12 males) underwent diffusion tensor imaging, to create fractional anisotropy (FA) and mean diffusivity (MD) images. To minimize the partial volume artifacts near the edge of WM, the WM was first segmented from the b0 image and used to extract WM only maps of FA and MD image. The WM masked FA, MD, and WM image were spatially normalized to MNI space using SPM DARTEL, and smoothed at 8 mm FWHM Gaussian. The smoothed-normalized-masked FA and MD images were then divided by the smoothed-normalized WM image to correct blurring artifacts caused by the spatial smoothing. The resulting FA and MD images were separately analyzed by voxel-based ANCOVA at a cluster size threshold of >30 voxels and p-value of < 0.05, corrected for multiple comparisons. RESULTS Compared with the TD, the ASD and DD showed significantly reduced FA in bilateral uncinate, arcuate, inferior fronto-occipital fasciculi, inferior longitudinal fasciculi, and corpus callosum. The reduction was larger in the DD group. Furthermore, the DD group also showed significant FA reduction in bilateral thalami, cinguli, amygdale and midbrain. Compared with the ASD group, the DD group showed significant FA reduction in bilateral uncinate and amygdala. No significant MD difference was found in “TD vs. ASD” and “ASD vs. DD” group, but the DD group showed increased MD in right arcuate and left inferior fronto-occipital fasciculi compared with the TD group. CONCLUSION Our study revealed significant abnormal microstructural integrity of the white matter in the regions of several association and limbic pathways, as well as in corpus callosum in children with ASD and DD, suggesting that there may be a developmental dysregulation in the formation of neuronal networks in ASD and DD. CLINICAL RELEVANCE/APPLICATION The findings in the present study could be used as imaging biomarkers for ASD and DD.
ABSTRACT PURPOSE To determine whether curvature analyses of frontal lobe white matter tracts can ... more ABSTRACT PURPOSE To determine whether curvature analyses of frontal lobe white matter tracts can yield an imaging parameter unique to children with autism spectrum disorder (ASD). METHOD AND MATERIALS Diffusion tensor MRI with 6 directional gradients and one b0 image was performed in 32 ASD children (mean age: 58.8±22.64 months, 29 males) and 14 normal controls (NC, mean age: 67.36±23.81 months, 11 males). Conventional streamline tractography and SPM DARTEL were used to isolate whole brain fiber tracts spatially normalized to MNI space. Subsequently, atalas-based ROI appraoch was used to isolate bilateral uncinate fasciculus (UF), arcuate fasciculus (AF), and genu of corpus callosum (gCC). For each fiber tract, tract-based morphometry (TBM) analysis was applied to localize the regions showing significant change in the curvature. The longest fiber penetrating the highest fiber density region of a given tract in the NC group was selected as a ‘prototype’ for that particular tract and was used to define the common arc-length coordinates for that tract. This prototyp was used to find the corresponding coordinates of individual fibers of the respective tract in each subject. Using Frenet’s equation, the curvature of each fiber tract at each coordinate was calculated in each subject and their group difference was examined by two sample t-test corrected for multiple comparisons . RESULTS Significantly higher curvature values (p<0.05) were found for all the measured tracts in the ASD group compared to controls, a result of sharper bends at the fronto-temporal junction for UF (0.18±0.05 vs. 0.16±0.04), at the parieto-temporal junction for AF (0.18+0.03 vs. 0.14±0.03), and at the midline of the gCC (0.17±0.02 vs. 0.13±0.01, respectively). These regions are indicated by black arrows in the attached figure. CONCLUSION Bilateral AF and UF, and gCC have higher curvature and sharper bending in children with ASD, perhaps resulting from differences in brain growth. CLINICAL RELEVANCE/APPLICATION Our finding suggests that the fiber tract curvature can be used as robust feature to quantify aberrant white matter geometry (developmental trajectory) in children with ASD.
ABSTRACT Thermochemical conversion of biomass results in producer gas as a raw material for the p... more ABSTRACT Thermochemical conversion of biomass results in producer gas as a raw material for the production of power, many fuels, and chemicals. It is important to clean producer gas of its tars before its intended use. Three different commercial catalysts, one platinum based (cerium zirconium platinum) and two nickel based (Hifuel R110 and Reformax 250), were investigated for their ability to convert toluene (model tar). Studies were carried out in a fixed bed reactor using a gas mixture comparable to the producer gas composition produced from switchgrass gasification. The operating parameters tested were space time (6.86 × 10 ‐4 to 1.262 × 10 ‐3 kg h m ‐3) corresponding to different catalyst loadings and catalyst particle sizes (pellets and powder). Decreasing the particle size resulted in better toluene conversion for all three catalysts. Additionally, an increase in space time resulted in an increase in toluene conversion. Furthermore, an overall increase in H 2 and CO 2 concentrations and an overall decrease in CH 4 and CO concentrations were observed during toluene conversion. Rate constants were calculated for all three catalysts. here is a growing demand for energy all over the world. It is estimated that the energy consumption from 2006 to 2030 will increase by 44% (EIA, 2009). Energy production processes of the future should be sustainable, cost‐effective, and reliable, and the process of production as well as the end product should be safe and environmentally friendly. Bioenergy, which is energy derived from biomass, seems to be a promising fit to this future energy demand. At Oklahoma State University (OSU), a gasification and fermentation process is being investigated for production of ethanol from biomass. A gasification process is used to generate producer gas, a mixture of gases such as CO 2 , H 2 , N 2 , CH 4 , and CO, along with other high molecular weight hydrocarbons, char, and ash. The gas is then fed into a bioreactor where ethanol is produced. However, the primary disadvantage of this method is the formation of organics known as tars during gasification (Nordgreen et al., 2006; Abu El‐Rub et al., 2004). Several definitions of tars are available, but tars can be defined as organics that have a molecular weight higher than that of benzene and are produced by thermal or partial oxidation of biomass (Milne et al., 1998). Producer gas must be cleaned of tars before it can be effectively used. Several methods are available for the removal of tars. The use of catalysts to Submitted for review in March 2011 as manuscript number FPE 9095; approved for publication by the Food & Process Engineering Institute Division of ASABE in August 2011.
Streptococcus pneumoniae is a leading cause of bacterial pneumonia, sepsis and meningitis. Surfac... more Streptococcus pneumoniae is a leading cause of bacterial pneumonia, sepsis and meningitis. Surface accessible proteins of S. pneumoniae are being explored for the development of a protein-based vaccine in order to overcome the limitations of existing polysaccharide-based pneumococcal vaccines. To identify a potential vaccine candidate, we resolved surface-associated proteins of S. pneumoniae TIGR4 strain using two-dimensional gel electrophoresis followed by immunoblotting with antisera generated against whole heat-killed TIGR4. Ten immunoreactive spots were identified by mass spectrometric analysis that included a putative lipoprotein SP0845. Analysis of the inferred amino acid sequence of sp0845 homologues from 36 pneumococcal strains indicated that SP0845 was highly conserved (>98% identity) and showed less than 11% identity with any human protein. Our bioinformatic and functional analyses demonstrated that SP0845 is the substrate-binding protein of an ATP-binding cassette (ABC) transporter that is involved in nucleoside uptake with cytidine, uridine, guanosine and inosine as the preferred substrates. Deletion of the gene encoding SP0845 renders pneumococci avirulent suggesting that it is essential for virulence. Immunoblot analysis suggested that SP0845 is expressed in in vitro grown pneumococci and during mice infection. Immunofluorescence microscopy and flow cytometry data indicated that SP0845 is surface exposed in encapsulated strains and accessible to antibodies. Subcutaneous immunization with recombinant SP0845 induced high titer antibodies in mice. Hyperimmune sera raised against SP0845 promoted killing of…
ABSTRACT Software testing is an essential part of software life cycle as during this period, an e... more ABSTRACT Software testing is an essential part of software life cycle as during this period, an effort is made to improve software reliability and quality. In this phase, perfect debugging is not possible because of time lag in fault removal process or new faults may get introduced in fault removal and fault detection process. In this paper, we have studied software reliability growth model (SRGM) incorporating generalized modified Weibull (GMW) testing effort function in imperfect debugging environment with constant and time varying fault detection rates, respectively. The parameters involved in the models are estimated using maximum likelihood estimation (MLE) and non-linear least square estimation (NLLSE) methods. The performance of the proposed models is validated using mean square error (MSE), accuracy of estimation (AE), chi(2) test, etc. Moreover, optimal release policy is discussed by keeping fault detection rate as a constant using both genetic algorithm (GA) and multi-attribute utility theory (MAUT). A comparison has been made with existing models reported in literature. From the empirical results, it is observed that our proposed models performed better. Further, the reliability measures are more factual in the case of time varying fault detection rate in comparison to constant fault detection rate model.
Megachannel is a newly developed colonic access system allowing rapid and multiple passes of the ... more Megachannel is a newly developed colonic access system allowing rapid and multiple passes of the colonoscope to the right side of the colon.The aim of this study was to evaluate the safety and clinical feasibility of placing a 100 cm Megachannel prototype in the right side of the colon.Six centers, international, both surgeons and gastroenterologists performing endoscopy.Patients scheduled for colonoscopy with suspected right-side colonic polypoid lesions were included. The prototype was loaded onto a 160 cm lower GI endoscope and introduced via colonoscopic guidance.The ability to place this device in the right side of the colon.The Megachannel prototype was introduced in 41 patients (19 female, mean age 54 years) undergoing colonoscopy. The cecum was reached in 27 cases (66%) within 18 minutes (range, 3-35 minutes) and with 73 cm (range, 40-100 cm) of the device being inserted into the colon. Mild tissue bruises and mild pain were observed in 5 and 3 patients, respectively. In 14 patients, the device assisted the removal of multiple polyps (2-12) as tissue was repeatedly retrieved through the channel. The device also allowed delivery of an endoscopic US scope or suction caps to the right side of the colon.Prototype performance may differ from the actual product (80 cm in length, redesigned introducer plugs). Small number of patients, difficult in diverticular disease.This newly developed colonic access system can be safely placed in the right side of the colon and is useful for a variety of advanced procedures that require repeated insertion of the colonoscope or delivery of bulky instruments. (Clinical trial registration number: NCT00987896.)
This study provides a retrospective analysis of 60 patients who underwent thoracic reconstruction... more This study provides a retrospective analysis of 60 patients who underwent thoracic reconstruction with the omentum. Patients were identified by searching several databases to determine demographics, indications for surgery, operative technique, and postoperative course, including donor and recipient site morbidity. From January 1975 to May 2000, the authors harvested and transferred the omentum successfully (57 pedicled, 3 free) in 60 patients (mean age, 60 years; age range, 21-86 years) for sternal wound infections (N = 34), chest wall resections (N = 17), pectus deformities (N = 2), intrathoracic defects (N = 4), and breast reconstruction (N = 3). The omentum was used as a primary flap in 39 patients and as a salvage flap in 21 patients. Average operative time was 3.9 hours and average hospital stay was 34.3 days. Partial flap loss occurred in 7 patients, with no total flap failures. Morbidity included six abdominal wound infections and seven epigastric hernias. Mortality was 11.7%. The omentum can be harvested safely and used reliably to reconstruct varying thoracic wounds and defects. Specific indications from this series include osteoradionecrosis, chest wall tumors, massive sternal wounds, and refractory mediastinitis. Hultman CS, Culbertson JH, Jones GE, et al. Thoracic reconstruction with the omentum: indications, complications, and results.
ABSTRACT PURPOSE To study white matter (WM) properties in young children with autism spectrum dis... more ABSTRACT PURPOSE To study white matter (WM) properties in young children with autism spectrum disorder (ASD) and developmental delay (DD), we performed tissue-specific, smoothing-compensated (T-SPOON) analysis which is optimized for the voxel-based morphometry study. METHOD AND MATERIALS Thirty-one children with ASD (mean age: 5±1.7 years; 28 males), 11 children with DD (mean age: 4.4±1.7 years; 9 males), and 14 typically developing children (TD, mean age: 5.5±1.9 years; 12 males) underwent diffusion tensor imaging, to create fractional anisotropy (FA) and mean diffusivity (MD) images. To minimize the partial volume artifacts near the edge of WM, the WM was first segmented from the b0 image and used to extract WM only maps of FA and MD image. The WM masked FA, MD, and WM image were spatially normalized to MNI space using SPM DARTEL, and smoothed at 8 mm FWHM Gaussian. The smoothed-normalized-masked FA and MD images were then divided by the smoothed-normalized WM image to correct blurring artifacts caused by the spatial smoothing. The resulting FA and MD images were separately analyzed by voxel-based ANCOVA at a cluster size threshold of >30 voxels and p-value of < 0.05, corrected for multiple comparisons. RESULTS Compared with the TD, the ASD and DD showed significantly reduced FA in bilateral uncinate, arcuate, inferior fronto-occipital fasciculi, inferior longitudinal fasciculi, and corpus callosum. The reduction was larger in the DD group. Furthermore, the DD group also showed significant FA reduction in bilateral thalami, cinguli, amygdale and midbrain. Compared with the ASD group, the DD group showed significant FA reduction in bilateral uncinate and amygdala. No significant MD difference was found in “TD vs. ASD” and “ASD vs. DD” group, but the DD group showed increased MD in right arcuate and left inferior fronto-occipital fasciculi compared with the TD group. CONCLUSION Our study revealed significant abnormal microstructural integrity of the white matter in the regions of several association and limbic pathways, as well as in corpus callosum in children with ASD and DD, suggesting that there may be a developmental dysregulation in the formation of neuronal networks in ASD and DD. CLINICAL RELEVANCE/APPLICATION The findings in the present study could be used as imaging biomarkers for ASD and DD.
ABSTRACT PURPOSE To determine whether curvature analyses of frontal lobe white matter tracts can ... more ABSTRACT PURPOSE To determine whether curvature analyses of frontal lobe white matter tracts can yield an imaging parameter unique to children with autism spectrum disorder (ASD). METHOD AND MATERIALS Diffusion tensor MRI with 6 directional gradients and one b0 image was performed in 32 ASD children (mean age: 58.8±22.64 months, 29 males) and 14 normal controls (NC, mean age: 67.36±23.81 months, 11 males). Conventional streamline tractography and SPM DARTEL were used to isolate whole brain fiber tracts spatially normalized to MNI space. Subsequently, atalas-based ROI appraoch was used to isolate bilateral uncinate fasciculus (UF), arcuate fasciculus (AF), and genu of corpus callosum (gCC). For each fiber tract, tract-based morphometry (TBM) analysis was applied to localize the regions showing significant change in the curvature. The longest fiber penetrating the highest fiber density region of a given tract in the NC group was selected as a ‘prototype’ for that particular tract and was used to define the common arc-length coordinates for that tract. This prototyp was used to find the corresponding coordinates of individual fibers of the respective tract in each subject. Using Frenet’s equation, the curvature of each fiber tract at each coordinate was calculated in each subject and their group difference was examined by two sample t-test corrected for multiple comparisons . RESULTS Significantly higher curvature values (p<0.05) were found for all the measured tracts in the ASD group compared to controls, a result of sharper bends at the fronto-temporal junction for UF (0.18±0.05 vs. 0.16±0.04), at the parieto-temporal junction for AF (0.18+0.03 vs. 0.14±0.03), and at the midline of the gCC (0.17±0.02 vs. 0.13±0.01, respectively). These regions are indicated by black arrows in the attached figure. CONCLUSION Bilateral AF and UF, and gCC have higher curvature and sharper bending in children with ASD, perhaps resulting from differences in brain growth. CLINICAL RELEVANCE/APPLICATION Our finding suggests that the fiber tract curvature can be used as robust feature to quantify aberrant white matter geometry (developmental trajectory) in children with ASD.
ABSTRACT Thermochemical conversion of biomass results in producer gas as a raw material for the p... more ABSTRACT Thermochemical conversion of biomass results in producer gas as a raw material for the production of power, many fuels, and chemicals. It is important to clean producer gas of its tars before its intended use. Three different commercial catalysts, one platinum based (cerium zirconium platinum) and two nickel based (Hifuel R110 and Reformax 250), were investigated for their ability to convert toluene (model tar). Studies were carried out in a fixed bed reactor using a gas mixture comparable to the producer gas composition produced from switchgrass gasification. The operating parameters tested were space time (6.86 × 10 ‐4 to 1.262 × 10 ‐3 kg h m ‐3) corresponding to different catalyst loadings and catalyst particle sizes (pellets and powder). Decreasing the particle size resulted in better toluene conversion for all three catalysts. Additionally, an increase in space time resulted in an increase in toluene conversion. Furthermore, an overall increase in H 2 and CO 2 concentrations and an overall decrease in CH 4 and CO concentrations were observed during toluene conversion. Rate constants were calculated for all three catalysts. here is a growing demand for energy all over the world. It is estimated that the energy consumption from 2006 to 2030 will increase by 44% (EIA, 2009). Energy production processes of the future should be sustainable, cost‐effective, and reliable, and the process of production as well as the end product should be safe and environmentally friendly. Bioenergy, which is energy derived from biomass, seems to be a promising fit to this future energy demand. At Oklahoma State University (OSU), a gasification and fermentation process is being investigated for production of ethanol from biomass. A gasification process is used to generate producer gas, a mixture of gases such as CO 2 , H 2 , N 2 , CH 4 , and CO, along with other high molecular weight hydrocarbons, char, and ash. The gas is then fed into a bioreactor where ethanol is produced. However, the primary disadvantage of this method is the formation of organics known as tars during gasification (Nordgreen et al., 2006; Abu El‐Rub et al., 2004). Several definitions of tars are available, but tars can be defined as organics that have a molecular weight higher than that of benzene and are produced by thermal or partial oxidation of biomass (Milne et al., 1998). Producer gas must be cleaned of tars before it can be effectively used. Several methods are available for the removal of tars. The use of catalysts to Submitted for review in March 2011 as manuscript number FPE 9095; approved for publication by the Food & Process Engineering Institute Division of ASABE in August 2011.
Streptococcus pneumoniae is a leading cause of bacterial pneumonia, sepsis and meningitis. Surfac... more Streptococcus pneumoniae is a leading cause of bacterial pneumonia, sepsis and meningitis. Surface accessible proteins of S. pneumoniae are being explored for the development of a protein-based vaccine in order to overcome the limitations of existing polysaccharide-based pneumococcal vaccines. To identify a potential vaccine candidate, we resolved surface-associated proteins of S. pneumoniae TIGR4 strain using two-dimensional gel electrophoresis followed by immunoblotting with antisera generated against whole heat-killed TIGR4. Ten immunoreactive spots were identified by mass spectrometric analysis that included a putative lipoprotein SP0845. Analysis of the inferred amino acid sequence of sp0845 homologues from 36 pneumococcal strains indicated that SP0845 was highly conserved (>98% identity) and showed less than 11% identity with any human protein. Our bioinformatic and functional analyses demonstrated that SP0845 is the substrate-binding protein of an ATP-binding cassette (ABC) transporter that is involved in nucleoside uptake with cytidine, uridine, guanosine and inosine as the preferred substrates. Deletion of the gene encoding SP0845 renders pneumococci avirulent suggesting that it is essential for virulence. Immunoblot analysis suggested that SP0845 is expressed in in vitro grown pneumococci and during mice infection. Immunofluorescence microscopy and flow cytometry data indicated that SP0845 is surface exposed in encapsulated strains and accessible to antibodies. Subcutaneous immunization with recombinant SP0845 induced high titer antibodies in mice. Hyperimmune sera raised against SP0845 promoted killing of…
ABSTRACT Software testing is an essential part of software life cycle as during this period, an e... more ABSTRACT Software testing is an essential part of software life cycle as during this period, an effort is made to improve software reliability and quality. In this phase, perfect debugging is not possible because of time lag in fault removal process or new faults may get introduced in fault removal and fault detection process. In this paper, we have studied software reliability growth model (SRGM) incorporating generalized modified Weibull (GMW) testing effort function in imperfect debugging environment with constant and time varying fault detection rates, respectively. The parameters involved in the models are estimated using maximum likelihood estimation (MLE) and non-linear least square estimation (NLLSE) methods. The performance of the proposed models is validated using mean square error (MSE), accuracy of estimation (AE), chi(2) test, etc. Moreover, optimal release policy is discussed by keeping fault detection rate as a constant using both genetic algorithm (GA) and multi-attribute utility theory (MAUT). A comparison has been made with existing models reported in literature. From the empirical results, it is observed that our proposed models performed better. Further, the reliability measures are more factual in the case of time varying fault detection rate in comparison to constant fault detection rate model.
Megachannel is a newly developed colonic access system allowing rapid and multiple passes of the ... more Megachannel is a newly developed colonic access system allowing rapid and multiple passes of the colonoscope to the right side of the colon.The aim of this study was to evaluate the safety and clinical feasibility of placing a 100 cm Megachannel prototype in the right side of the colon.Six centers, international, both surgeons and gastroenterologists performing endoscopy.Patients scheduled for colonoscopy with suspected right-side colonic polypoid lesions were included. The prototype was loaded onto a 160 cm lower GI endoscope and introduced via colonoscopic guidance.The ability to place this device in the right side of the colon.The Megachannel prototype was introduced in 41 patients (19 female, mean age 54 years) undergoing colonoscopy. The cecum was reached in 27 cases (66%) within 18 minutes (range, 3-35 minutes) and with 73 cm (range, 40-100 cm) of the device being inserted into the colon. Mild tissue bruises and mild pain were observed in 5 and 3 patients, respectively. In 14 patients, the device assisted the removal of multiple polyps (2-12) as tissue was repeatedly retrieved through the channel. The device also allowed delivery of an endoscopic US scope or suction caps to the right side of the colon.Prototype performance may differ from the actual product (80 cm in length, redesigned introducer plugs). Small number of patients, difficult in diverticular disease.This newly developed colonic access system can be safely placed in the right side of the colon and is useful for a variety of advanced procedures that require repeated insertion of the colonoscope or delivery of bulky instruments. (Clinical trial registration number: NCT00987896.)
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