The development of synthetic supramolecular compounds that mimic enzyme catalysts with well-defin... more The development of synthetic supramolecular compounds that mimic enzyme catalysts with well-defined internal environments represents a novel approach to improving the ability to control the rate and selectivity of organometallic reactions. Rather than using many different ...
Supramolecular chemistry represents a way to mimic enzyme reactivity by using specially designed ... more Supramolecular chemistry represents a way to mimic enzyme reactivity by using specially designed container molecules. We have shown that a chiral self-assembled M4L6 supramolecular tetrahedron can encapsulate a variety of cationic guests with varying degrees of stereoselectivity. Reactive iridium guests can be encapsulated, and the C-H bond activation of aldehydes occurs with the host cavity controlling the ability of substrates to interact with the metal center based upon size and shape. In addition, the host container can act as a catalyst by itself. By restricting reaction space and preorganizing the substrates into reactive conformations, it accelerates the sigmatropic rearrangement of enammonium cations.
International Journal of Radiation Oncology Biology Physics, 1996
A previously reported randomized trial from out institution demonstrated a local control advantag... more A previously reported randomized trial from out institution demonstrated a local control advantage to adjuvant brachytherapy (BRT) for completely resected high grade soft tissue sarcoma (STS). In recent years, BRT boost has been combined with wide field external beam radiotherapy (EBRT) for selected patients in whom the margin(s) of resection was positive. This study evaluates the impact of BRT boost plus EBRT on local control in this subset of patients and on wound complication rates. Between January, 1987 and December, 1992, 105 adult patients with primary or locally recurrent high grade STS of the extremity were treated with wide local excision and BRT alone (87 patients; dose: 45 Gy) or BRT plus EBRT (18 patients; dose: 15-20 Gy BRT + 45-50 Gy EBRT). The margin(s) of resection was positive in 10 out of 18 patients in the BRT + EBRT group vs. 17 out of 87 patients in the BRT alone group. Wound complications were classified as major if they required further operative intervention; moderate if there was purulent discharge, hematoma > 25 ml, wound separation > 2 cm, and persistent seroma requiring drainage; or minor if less than moderate. Median follow-up was 22 months. The overall 2-year actuarial local control rate was 86%. There was no difference in the 2-year actuarial local control rate between the BRT + EBRT group (90%) and the BRT alone group (82%) (9 = 0.32). However, for patients with positive resection margins the use of BRT + EBRT produced better local control than BRT alone [9 out of 10 (90%) vs. 10 out of 17 (59%)]. This difference approached but did not reach statistical significance (p = 0.08). No difference was seen in patients with negative margins. There was no significant difference in the overall wound complication rate (26% BRT vs. 38% BRT + EBRT, p = 0.31) nor in the combined major and moderate wound complication rate (16% BRT vs. 27% BRT + EBRT, p = 0.39). Our preliminary data suggest a trend in favor of BRT boost + EBRT as the optimal adjuvant local strategy for STS with positive resection margins. There is no significant difference in the wound complication rate with either technique.
The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify ... more The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify their biology have included recurrent and primary tumors as well as tumors from both intra- and extra-abdominal sites. The purpose of this study was to analyze patients with primary extremity and trunk desmoid tumors treated and followed at a single institution and to determine factors influencing disease free survival. Between July 1982 and June 1997, 189 patients with extremity and superficial trunk desmoid tumors were treated and followed prospectively. Of these, 105 presented with primary disease and formed the basis of this study. The median follow-up for the entire group of patients was 49 months; it was 46 months for patients who did not develop a local recurrence. During this time, 24 patients (23%) had a local recurrence. No patients died of disease. The 2-year and 5-year local recurrence free survival rates were 80% and 75%, respectively. None of the prognostic factors analyzed, including age, gender, depth of tumor, size of tumor, or tumor site, were significant for predicting local recurrence. Moreover, positive resection margins were not predictive of recurrence. The selective use of adjuvant radiation therapy did not influence the rate of local recurrence regardless of the margin status. Attempts to achieve negative resection margins may result in unnecessary morbidity and may not prevent local recurrence. Operations that preserve function and structure should be the primary goal, because the presence of residual disease cannot be clearly shown to impact adversely on 5-year disease free or overall survival.
The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify ... more The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify their biology have included recurrent and primary tumors as well as tumors from both intra- and extra-abdominal sites. The purpose of this study was to analyze patients with primary extremity and trunk desmoid tumors treated and followed at a single institution and to determine factors influencing disease free survival. Between July 1982 and June 1997, 189 patients with extremity and superficial trunk desmoid tumors were treated and followed prospectively. Of these, 105 presented with primary disease and formed the basis of this study. The median follow-up for the entire group of patients was 49 months; it was 46 months for patients who did not develop a local recurrence. During this time, 24 patients (23%) had a local recurrence. No patients died of disease. The 2-year and 5-year local recurrence free survival rates were 80% and 75%, respectively. None of the prognostic factors analyzed, including age, gender, depth of tumor, size of tumor, or tumor site, were significant for predicting local recurrence. Moreover, positive resection margins were not predictive of recurrence. The selective use of adjuvant radiation therapy did not influence the rate of local recurrence regardless of the margin status. Attempts to achieve negative resection margins may result in unnecessary morbidity and may not prevent local recurrence. Operations that preserve function and structure should be the primary goal, because the presence of residual disease cannot be clearly shown to impact adversely on 5-year disease free or overall survival.
Fuel cell coupled with biomass-derived fuel processor can convert renewable energy into a useful ... more Fuel cell coupled with biomass-derived fuel processor can convert renewable energy into a useful form in an environmental-friendly and CO 2 -neutral manner. It is considered as one of the most promising energy supply systems in the future. Biomass-derived fuels, such as ethanol, ...
Bio-ethanol is a prosperous renewable energy carrier mainly produced from biomass fermentation. R... more Bio-ethanol is a prosperous renewable energy carrier mainly produced from biomass fermentation. Reforming of bio-ethanol provides a promising method for hydrogen production from renewable resources. Besides operating conditions, the use of catalysts ...
This paper investigates the effects of solar radiation (in the form of ground-level heating) on t... more This paper investigates the effects of solar radiation (in the form of ground-level heating) on the air exchange rate (AER) of an idealized street canyon using computational fluid dynamic (CFD) technique. A two-dimensional numerical model based on Reynolds-averaged Navier–Stokes equations equipped with the standard, Renormalization Group (RNG), and realizable k−ε turbulence models was developed using the commercial CFD code FLUENT.
The development of synthetic supramolecular compounds that mimic enzyme catalysts with well-defin... more The development of synthetic supramolecular compounds that mimic enzyme catalysts with well-defined internal environments represents a novel approach to improving the ability to control the rate and selectivity of organometallic reactions. Rather than using many different ...
Supramolecular chemistry represents a way to mimic enzyme reactivity by using specially designed ... more Supramolecular chemistry represents a way to mimic enzyme reactivity by using specially designed container molecules. We have shown that a chiral self-assembled M4L6 supramolecular tetrahedron can encapsulate a variety of cationic guests with varying degrees of stereoselectivity. Reactive iridium guests can be encapsulated, and the C-H bond activation of aldehydes occurs with the host cavity controlling the ability of substrates to interact with the metal center based upon size and shape. In addition, the host container can act as a catalyst by itself. By restricting reaction space and preorganizing the substrates into reactive conformations, it accelerates the sigmatropic rearrangement of enammonium cations.
International Journal of Radiation Oncology Biology Physics, 1996
A previously reported randomized trial from out institution demonstrated a local control advantag... more A previously reported randomized trial from out institution demonstrated a local control advantage to adjuvant brachytherapy (BRT) for completely resected high grade soft tissue sarcoma (STS). In recent years, BRT boost has been combined with wide field external beam radiotherapy (EBRT) for selected patients in whom the margin(s) of resection was positive. This study evaluates the impact of BRT boost plus EBRT on local control in this subset of patients and on wound complication rates. Between January, 1987 and December, 1992, 105 adult patients with primary or locally recurrent high grade STS of the extremity were treated with wide local excision and BRT alone (87 patients; dose: 45 Gy) or BRT plus EBRT (18 patients; dose: 15-20 Gy BRT + 45-50 Gy EBRT). The margin(s) of resection was positive in 10 out of 18 patients in the BRT + EBRT group vs. 17 out of 87 patients in the BRT alone group. Wound complications were classified as major if they required further operative intervention; moderate if there was purulent discharge, hematoma > 25 ml, wound separation > 2 cm, and persistent seroma requiring drainage; or minor if less than moderate. Median follow-up was 22 months. The overall 2-year actuarial local control rate was 86%. There was no difference in the 2-year actuarial local control rate between the BRT + EBRT group (90%) and the BRT alone group (82%) (9 = 0.32). However, for patients with positive resection margins the use of BRT + EBRT produced better local control than BRT alone [9 out of 10 (90%) vs. 10 out of 17 (59%)]. This difference approached but did not reach statistical significance (p = 0.08). No difference was seen in patients with negative margins. There was no significant difference in the overall wound complication rate (26% BRT vs. 38% BRT + EBRT, p = 0.31) nor in the combined major and moderate wound complication rate (16% BRT vs. 27% BRT + EBRT, p = 0.39). Our preliminary data suggest a trend in favor of BRT boost + EBRT as the optimal adjuvant local strategy for STS with positive resection margins. There is no significant difference in the wound complication rate with either technique.
The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify ... more The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify their biology have included recurrent and primary tumors as well as tumors from both intra- and extra-abdominal sites. The purpose of this study was to analyze patients with primary extremity and trunk desmoid tumors treated and followed at a single institution and to determine factors influencing disease free survival. Between July 1982 and June 1997, 189 patients with extremity and superficial trunk desmoid tumors were treated and followed prospectively. Of these, 105 presented with primary disease and formed the basis of this study. The median follow-up for the entire group of patients was 49 months; it was 46 months for patients who did not develop a local recurrence. During this time, 24 patients (23%) had a local recurrence. No patients died of disease. The 2-year and 5-year local recurrence free survival rates were 80% and 75%, respectively. None of the prognostic factors analyzed, including age, gender, depth of tumor, size of tumor, or tumor site, were significant for predicting local recurrence. Moreover, positive resection margins were not predictive of recurrence. The selective use of adjuvant radiation therapy did not influence the rate of local recurrence regardless of the margin status. Attempts to achieve negative resection margins may result in unnecessary morbidity and may not prevent local recurrence. Operations that preserve function and structure should be the primary goal, because the presence of residual disease cannot be clearly shown to impact adversely on 5-year disease free or overall survival.
The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify ... more The natural history of desmoid tumors remains an enigma. Previous reports attempting to identify their biology have included recurrent and primary tumors as well as tumors from both intra- and extra-abdominal sites. The purpose of this study was to analyze patients with primary extremity and trunk desmoid tumors treated and followed at a single institution and to determine factors influencing disease free survival. Between July 1982 and June 1997, 189 patients with extremity and superficial trunk desmoid tumors were treated and followed prospectively. Of these, 105 presented with primary disease and formed the basis of this study. The median follow-up for the entire group of patients was 49 months; it was 46 months for patients who did not develop a local recurrence. During this time, 24 patients (23%) had a local recurrence. No patients died of disease. The 2-year and 5-year local recurrence free survival rates were 80% and 75%, respectively. None of the prognostic factors analyzed, including age, gender, depth of tumor, size of tumor, or tumor site, were significant for predicting local recurrence. Moreover, positive resection margins were not predictive of recurrence. The selective use of adjuvant radiation therapy did not influence the rate of local recurrence regardless of the margin status. Attempts to achieve negative resection margins may result in unnecessary morbidity and may not prevent local recurrence. Operations that preserve function and structure should be the primary goal, because the presence of residual disease cannot be clearly shown to impact adversely on 5-year disease free or overall survival.
Fuel cell coupled with biomass-derived fuel processor can convert renewable energy into a useful ... more Fuel cell coupled with biomass-derived fuel processor can convert renewable energy into a useful form in an environmental-friendly and CO 2 -neutral manner. It is considered as one of the most promising energy supply systems in the future. Biomass-derived fuels, such as ethanol, ...
Bio-ethanol is a prosperous renewable energy carrier mainly produced from biomass fermentation. R... more Bio-ethanol is a prosperous renewable energy carrier mainly produced from biomass fermentation. Reforming of bio-ethanol provides a promising method for hydrogen production from renewable resources. Besides operating conditions, the use of catalysts ...
This paper investigates the effects of solar radiation (in the form of ground-level heating) on t... more This paper investigates the effects of solar radiation (in the form of ground-level heating) on the air exchange rate (AER) of an idealized street canyon using computational fluid dynamic (CFD) technique. A two-dimensional numerical model based on Reynolds-averaged Navier–Stokes equations equipped with the standard, Renormalization Group (RNG), and realizable k−ε turbulence models was developed using the commercial CFD code FLUENT.
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