Assessment of Planetary Boundary Layer parametrizations and urban heat island comparison: Impacts and implications for tracer transport.

Accurate simulation of planetary boundary layer height (PBLH) is key to greenhouse gas emission estimation, air quality prediction and weather forecasting. This manuscript describes an extensive performance assessment of several Weather Research and Forecasting (WRF) model configurations where novel observations from ceilometers, surface stations and a flux tower were used to study their ability to reproduce planetary boundary layer heights (PBLH) and the impact that the urban heat island (UHI) has on the modeled PBLHs in the greater Washington, D.C. area. In addition, CO2 measurements at two urban towers were compared to tracer transport simulations. The ensemble of models used 4 PBL parameterizations, 2 sources of initial and boundary conditions and 1 configuration including the building energy parameterization (BEP) urban canopy model. Results have shown low biases over the whole domain and period for wind speed, wind direction and temperature with no drastic differences between meteorological drivers. We find that PBLH errors are mostly positively correlated with sensible heat flux errors, and that modeled positive UHI intensities are associated with deeper modeled PBLs over the urban areas. In addition, we find that modeled PBLHs are typically biased low during nighttime for most of the configurations with the exception of those using the MYNN parametrization and that these biases directly translate to tracer biases. Overall, the configurations using MYNN scheme performed the best, reproducing the PBLH and CO2 molar fractions reasonably well during all hours, thus opening the door to future nighttime inverse modeling.

Tumor size predicts long-term survival in colon cancer: an analysis of the National Cancer Data Base.

BACKGROUND: American Joint Committee on Cancer uses tumor size for "T" staging of many solid tumors for its effect on prognosis. However, tumor size has not been incorporated in tumor (T), nodal status (N), metastasis (M) staging for colon cancer. Hence, the National Cancer Data Base was used to determine whether tumor size correlates with TNM staging and survival. METHODS: For the 300,386 patients, tumor size was divided into S1 (0 to 2 cm), S2 (>2 to 4 cm), S3 (>4 to 6 cm), and S4 (>6 cm). Statistical comparison was done for TNM stage, grade, and nodal status with tumor size. Kaplan-Meier survival analysis was done for each "S" stage. RESULTS: Of the 300,386 patients, 13% were classified as S1, 39% S2, 30% S3 and 18% as S4. Right colon was the most common site (48%). Tumor size positively correlated with grade, T stage, and nodal stage. Tumor size was inversely associated with survival. CONCLUSION: Tumor size is positively correlated with important prognostic factors and negatively impacted survival.

Employment of on-line FT-IR spectroscopy to monitor the deprotection of a 9-fluorenylmethyl protected carboxylic acid peptide conjugate of doxorubicin.

A method for accurately determining the end-point, >98% conversion, of the deprotection reaction of a highly toxic 9-fluorenylmethyl (Fm) ester 1b to its corresponding carboxylate 1d in real time by FT-IR spectroscopy is reported. Advantages of this method over analysis by conventional chromatographic means include real time determination of the end-point of a reaction that is time sensitive to by-product formation, and elimination of sampling a highly toxic reaction mixture. The FT-IR method is based on monitoring, in real time, the disappearance of the Fm ester carbonyl band for 1b at 1737 cm(-1), during deprotection by piperidine, and calibration models were established by Partial Least Squares (PLS) regression analysis with high performance liquid chromatography (HPLC) as reference. The best calibration model was built with 5 PLS factors in the spectral range of 1780-1730 and 1551-1441 cm(-1) and resulted in a standard error of cross validation (SECV) of 0.63 mM 1b and a standard error of prediction (SEP) of 0.51 mM 1b in the range of 0-25 mM. This error of prediction is approximately 0.8% of the initial concentration of 1b and is well within our specifications of <2% initial concentration.