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CSM-CROPGRO-Cotton Model under DSSAT V 4.0.2.0 has been extensively tested and validated in many studies, mainly in United States. The objective of this study was to test and validate this model in three cotton growing regions of Pakistan (Faisalabad, Multan and Sahiwal) for dynamic simulation of development, growth and seed cotton yield of four cotton cultivars (CIM-496, CIM-506, NIAB-111 and SLH-284) at varying nitrogen increments (50, 100, 150 and 200 kg ha-1) sown at different timings (20 May and 10 June). The model was first calibrated with data (phenology, biomass, LAI, and yield components) collected during 2009 at all locations against the best performing treatment May 15 sowing, cv. CIM-496 and 200 kg N ha-1 (D1V1N4) in field trials. The model was then tested with data recorded against remaining thirty-one treatments for all locations. Similarly, the data of year 2010 was used for validation. The simulated values of crop phenology (days to anthesis and maturity) by the model were reliable with the recorded data, with root mean square error (RMSE) less than 2 days during both years. Although RMSE values for LAI approached higher than 1 in many of the treatments, these values for total dry matter and seed-cotton yield were reasonably good (367 to 497 kg ha-1and 122 to 227 kg ha-1, respectively). There is a dire need to assess impact of climate variation on seed cotton yield under various climatic regions of Pakistan to ensure fiber quality and yield in future. [ABSTRACT FROM AUTHOR]

This study examines the effect of foreign bank presence on the behaviour of domestic banks by using the annual data of 37 commercial banks comprising of 7 foreign and 30 domestic banks for the time period of 2007 to 2011. We investigated how net interest margin, return on assets, overhead costs, cost to income and nonperforming loans are effected by the foreign bank presence. We have used panel regression analysis employing bank specific fixed effect model. As a developing country case, the results suggest that the increase in foreign bank share effects the interest margins and profitability of domestic banks in a decreasing manner. It wouldn't be erroneous to express that foreign banks have a positive effect on the competitive environment of domestic banks increasing overall banking standard in Pakistan, the licensing policies should be further liberalized to let new entrants further improve the domestic financial intermediation system. [ABSTRACT FROM AUTHOR]

The study is an attempt to investigate the nature of competition and market contestability of 35 Pakistani banks for the period of 2007-2011 by employing Panzar and Rosse (PR-model). The test of competition overall sample (2007-2011) suggest that banks in Pakistan in state of monopolistic competition and market is in equilibrium. The sub sample (2007-2009) result of competition and equilibrium are similar as for sample period (2007-2011) suggesting that revenue produced during this period is state of monopolistic competition. Finally the results of sample period (2010-2011) suggest that banks in Pakistan are instate of perfect competition however, the market in not in long-run equilibrium. The results have interesting policy implications; it is suggested to encourage the foreign banks presence to improve the competitive condition of banking industry so that to ensure the exit and entrance of banks in the industry to increase the competition and produce the variety of product to improve banks performance and customer satisfaction. [ABSTRACT FROM AUTHOR]

We used disaggregated approach to test the validity of J-curve theory for Pakistan in bilateral trade with United Kingdom and United States, as these are the major trading partners of Pakistan having forty percent trade contribution to the total trade of Pakistan. The disaggregated approach is applied in order to avoid the aggregation bias and to captures the response of individual country price and income by calculating the real effective exchange rate for these countries. The separate equations have been estimated for each country. The vector error correction model has applied to find the impact of exchange rate depreciation on trade balance. The Johansen co-integration test is applied to test the long run relationship among the variables, trade balance, domestic gross domestic product and foreign gross domestic product and real effective exchange rate. To analyze the response of trade balance to exchange rate, impulse response analysis has used. The study support that Pakistan's trade balance follows J-curve pattern in bilateral trade with UK and USA. The cointegration results support the existence of long run relationship of exchange rate and trade balance which is quite clear from the existence of J-curve pattern. In short run the exchange rate depreciation has worsened the trade balance. Combining the short run and long run analysis with the help of impulse response we found support of existence of J-curve in trade of Pakistan with both UK and USA. [ABSTRACT FROM AUTHOR]

Every organization has to go through phase of struggle in always evolving external environments. Every Organization has to come up with new ways to increase effectiveness and efficiency of the business process. To remain competitive and sustainable the key is to invest in training. Due to the importance of training for any organization, this research is a spotlight on training process / workshops / programs identified through Training Need Assessment contributing towards employee development and their satisfaction towards training programs. [ABSTRACT FROM AUTHOR]

PET/MRI is a new hybrid imaging modality and has the potential to become a powerful imaging tool. It is currently one of the most active areas of research in diagnostic imaging. The characterisation of an incidental renal lesion can be difficult. In particular, the differentiation of an oncocytoma from other solid renal lesions such as renal cell carcinoma (RCC) represents a diagnostic challenge. We describe the detection of an incidental renal oncocytoma in a 79-year gentleman who underwent a re-staging 18F-Choline PET/MRI following a rise in PSA values (4.07, nadir 1.3). [ABSTRACT FROM AUTHOR]

Purpose: Treatment of metastatic colorectal cancer frequently includes antiangiogenic agents such as bevacizumab. Size measurements are inadequate to assess treatment response to these agents, and newer response assessment criteria are needed. We aimed to evaluate F-FDG PET-derived texture parameters in a preclinical colorectal cancer model as alternative metrics of response to treatment with bevacizumab., Materials and Methods: Fourteen CD1 athymic mice injected in the flank with 5×106 LS174T cells (human colorectal carcinoma) were either untreated controls (n=7) or bevacizumab treated (n=7). After 2 weeks, mice underwent F-FDG PET/CT. Calliper-measured tumor growth (Δvol) and final tumor volume (Volcal), F-FDG PET metabolically active volume (Volmet), mean metabolism (Metmean), and maximum metabolism (Metmax) were measured. Twenty-four texture features were compared between treated and untreated mice. Immunohistochemical mean tumor vascular density was estimated by anti-CD-34 staining after tumor resection., Results: Treated mice had significantly lower tumor vascular density (P=0.032), confirming the antiangiogenic therapeutic effect of bevacizumab. None of the conventional measures were different between the two groups: Δvol (P=0.9), Volcal (P=0.7), Volmet (P=0.28), Metmax (P=0.7), or Metmean (P=0.32). One texture parameter, GLSZM-SZV (visually indicating that the F-FDG PET images of treated mice comprise uniformly sized clusters of different activity) had significantly different means between the two groups of mice (P=0.001)., Conclusion: F-FDG PET derived texture parameters, particularly GLSZM-SZV, may be valid biomarkers of tumor response to treatment with bevacizumab, before change in volume.

Purpose: With the availability of ultra-sensitive PSA assays, early biochemical relapse (eBCR) of prostate cancer is increasingly being detected at values much lower than the conventional threshold of 0.2 ng/ml. Accurate localisation of disease in this setting may allow treatment modification and improved outcomes, especially in patients with pelvis-confined or extra-pelvic oligometastasis (defined as up to three pelvic nodal or distant sites). We aimed to measure the detection rate of [68]Ga-PSMA-HBNED-CC (PSMA)-PET/CT and its influence on patient management in eBCR of prostate cancer following radical prostatectomy (RP)., Methods: We retrospectively identified 28 patients who underwent PSMA-PET/CT for post-RP eBCR (PSA < 0.5 ng/ml) at our tertiary care cancer centre. Two nuclear medicine physicians independently recorded the sites of PSMA-PET/CT positivity. Multidisciplinary meeting records were accessed to determine changes in management decisions following PSMA-PET/CT scans., Results: The mean age of patients was 65.6 years (range: 50-76.2 years); median PSA was 0.22 ng/ml (interquartile range: 0.15 ng/ml to 0.34 ng/ml). Thirteen patients (46.4%) had received radiotherapy in the past. PSMA-PET/CT was positive in 17 patients (60.7%). Only one patient had polymetastasis (> 3 sites); the remainder either had prostatectomy bed recurrence (n = 2), pelvic oligometastasis (n = 10), or extra-pelvic oligometastasis (n = 4). PSMA-PET/CT resulted in management change in 12 patients (42.8%), involving stereotactic body radiotherapy (n = 6), salvage radiotherapy (n = 4), and systemic treatment (n = 2)., Conclusions: Our findings show that PSMA-PET/CT has a high detection rate in the eBCR setting following RP, with a large proportion of patients found to have fewer than three lesions. PSMA-PET/CT may be of value in patients with early PSA failure, and impact on the choice of potentially curative salvage treatments.

Purpose: Despite the growing use of fluorine-18-fluorodeoxyglucose (F-FDG) PET texture analysis to measure intratumoural heterogeneity in cancer research, the biologic basis of F-FDG PET-derived texture variables is poorly understood. We aimed to assess correlations between F-FDG PET-derived texture variables and whole-slide image (WSI)-derived metrics of tumour cellularity and spatial heterogeneity., Patients and Methods: Twenty-two patients with non-small-cell lung cancer prospectively underwent F-FDG PET imaging before tumour resection. We tested nine F-FDG PET parameters: metabolically active tumour volume, total lesion glycolysis, mean standardized uptake value (SUVmean), first-order entropy, energy, skewness, kurtosis, grey-level co-occurrence matrix entropy and lacunarity (SUV-lacunarity). From the haematoxylin and eosin-stained WSIs, we derived mean tumour-cell density (MCD) and lacunarity (path-lacunarity). Spearman's correlation analysis and agglomerative hierarchical clustering were performed to assess variable associations., Results: Tumour volumes ranged from 2.2 to 74 cm (median: 17.9 cm). MCD correlated positively with total lesion glycolysis (rs: 0.46, P: 0.007) and SUVmean (rs : 0.55; P: 0.008) and negatively with skewness and kurtosis (rs: -0.47 for both; P: 0.028 and 0.026, respectively). SUV-lacunarity and path-lacunarity were positively correlated (rs: 0.5; P: 0.018). On cluster analysis, larger tumours trended towards higher SUVmean and entropy with a predominance of tightly concentrated high SUV-voxels (negative skewness and low kurtosis on the histogram); on WSI analysis such larger tumours also displayed generally higher MCD and low SUV-lacunarity and path-lacunarity., Conclusion: Our data suggest that histopathological MCD and lacunarity are associated with several commonly used F-FDG PET-derived indices including SUV-lacunarity, metabolically active tumour volume, SUVmean, entropy, skewness, and kurtosis, and thus may explain the biological basis of F-FDG PET-uptake heterogeneity in non-small-cell lung cancer.

Background: Measures of tumour heterogeneity derived from 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) scans are increasingly reported as potential biomarkers of non-small cell lung cancer (NSCLC) for classification and prognostication. Several segmentation algorithms have been used to delineate tumours, but their effects on the reproducibility and predictive and prognostic capability of derived parameters have not been evaluated. The purpose of our study was to retrospectively compare various segmentation algorithms in terms of inter-observer reproducibility and prognostic capability of texture parameters derived from non-small cell lung cancer (NSCLC) 18 F-FDG PET/CT images. Fifty three NSCLC patients (mean age 65.8 years; 31 males) underwent pre-chemoradiotherapy 18 F-FDG PET/CT scans. Three readers segmented tumours using freehand (FH), 40% of maximum intensity threshold (40P), and fuzzy locally adaptive Bayesian (FLAB) algorithms. Intraclass correlation coefficient (ICC) was used to measure the inter-observer variability of the texture features derived by the three segmentation algorithms. Univariate cox regression was used on 12 commonly reported texture features to predict overall survival (OS) for each segmentation algorithm. Model quality was compared across segmentation algorithms using Akaike information criterion (AIC)., Results: 40P was the most reproducible algorithm (median ICC 0.9; interquartile range [IQR] 0.85-0.92) compared with FLAB (median ICC 0.83; IQR 0.77-0.86) and FH (median ICC 0.77; IQR 0.7-0.85). On univariate cox regression analysis, 40P found 2 out of 12 variables, i.e. first-order entropy and grey-level co-occurence matrix (GLCM) entropy, to be significantly associated with OS; FH and FLAB found 1, i.e., first-order entropy. For each tested variable, survival models for all three segmentation algorithms were of similar quality, exhibiting comparable AIC values with overlapping 95% CIs., Conclusions: Compared with both FLAB and FH, segmentation with 40P yields superior inter-observer reproducibility of texture features. Survival models generated by all three segmentation algorithms are of at least equivalent utility. Our findings suggest that a segmentation algorithm using a 40% of maximum threshold is acceptable for texture analysis of 18 F-FDG PET in NSCLC.

Objective: Texture analysis involves the mathematic processing of medical images to derive sets of numeric quantities that measure heterogeneity. Studies on lung cancer have shown that texture analysis may have a role in characterizing tumors and predicting patient outcome. This article outlines the mathematic basis of and the most recent literature on texture analysis in lung cancer imaging. We also describe the challenges facing the clinical implementation of texture analysis., Conclusion: Texture analysis of lung cancer images has been applied successfully to FDG PET and CT scans. Different texture parameters have been shown to be predictive of the nature of disease and of patient outcome. In general, it appears that more heterogeneous tumors on imaging tend to be more aggressive and to be associated with poorer outcomes and that tumor heterogeneity on imaging decreases with treatment. Despite these promising results, there is a large variation in the reported data and strengths of association.

Background: Tongue tumour thickness has been shown to have a correlation with neck nodal metastasis and hence patient survival. Current AJCC guidelines recommend inclusion of tongue tumour thickness measurement in routine radiologic staging. Several studies have attempted to define the accuracy of MRI in measuring tongue tumour thickness. The aim of our study was to compare tongue tumour thickness measured at T2-weighted and STIR sequences with histologic tongue tumour thickness., Methods: Twenty-eight consecutive patients of tongue cancer who had undergone glossectomy were selected retrospectively. Tumours were measured in both STIR axial and T2-weighted coronal images and compared with histologic tumour thickness on resected specimens. Pearson's analysis was performed to determine the degree of correlation. Paired samples t-test was also used for comparison of mean tumour thicknesses measured on MRI with mean histologic tumour thickness., Results: Pearson correlation analysis showed good correlation of tumour thickness measured on MRI with actual histologic tumour thickness (R=0.876)., Conclusion: MRI provides a satisfactory prediction of tongue tumour thickness which in turn can be used todetermine the need for elective neck dissection in these patients.