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Vitamin C degradation of broccoli at different moisture and temperature was measured as a function of storage time and modeled by first-order reaction kinetics. The variation of rate constant was analyzed based on the activation energy, glass transition, BET-monolayer, micro-region state diagram, and empirical correlations. Three domains of chemical reactions were observed as a function of temperature. In the case of broccoli with freezable water (i.e. moist), the first critical temperature (i.e. T c ) was observed at −20°C (T c /T g ′′′: 0.829), which was close to the T g ′′′ (i.e. experimental ultimate maximal-freezeconcentration glass transition) (−32.2°C); while second critical temperature (i.e. T s ) was observed at 60.0°C (i.e. T s /T g ′′′: 1.383). The activation energy values were 13.6, 75.0, and 43.6 kJ/mole for the phase 1 (moist-glassy), phase 2 (moistglassy-rubbery) and phase 3 (moist-rubbery-flow), respectively. In the case of frozen-broccoli with un-freezable water, the first critical temperature (i.e. T c ) was observed at 5°C (T c /T gi : 1.021), which was close to the T gi (onset glass transition) (−0.8°C); while the second critical temperature (i.e. T s ) was observed at 70.0°C (i.e. T s /T gi : 1.260). The second critical temperature was close to the mechanical glass transition temperature. The activation energy values were 13.1, 69.6, and 72.4 kJ/mole for phase 1, phase 2 and phase 3, respectively. Each experimental rate constant was located in the micro-regions of the state diagram. Principal component analysis showed that reaction rates can be grouped into different micro-regions, except one data point in the microregion 12. This could be due to the wider domain of this region and further sub-micro-regions could be defined. Finally, empirical correlations were developed as dimensionless moisture, temperature, and rate constant, and explored the possibility of developing a generic universal equation.

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There is no accepted surveillance strategy following curative oesophageal cancer management, with reinvestigation often relying on symptom development. Lack of a surveillance standard may impact on outcome and survival. We hypothesized that strict surveillance was more likely to detect curable recurrent disease. This study compared the outcome for salvage surgery for recurrent disease, detected on a strict surveillance program, with survival of patients that had undergone immediate surgery following an incomplete response to neoadjuvant chemoradiotherapy. A prospective database of oesophageal carcinoma patients who were treated with curative intent (Surgery alone, Neoadjuvant Chemoradiotherapy (NeoCR) plus surgery, Definitive Chemoradiotherapy or Neoadjuvant Chemoradiotherapy with surveillance by choice), was interrogated for patients with recurrent disease amenable to salvage surgery. Surveillance for all consisted of 3-monthly endoscopy and 6-monthly CT scanning for 3 years, followed by 6-monthly endoscopy and yearly CT scanning to 5 years, and both yearly thereafter. If recurrence was diagnosed patients were restaged and, if suitable, underwent salvage surgery. Their outcome was compared with patients undergoing neoadjuvant chemoradiotherapy and having immediate surgery for an incomplete response. Of 205 patients treated with curative intent, 18 (9%) underwent salvage surgery for locoregional recurrence. They had a median survival of 61.6 months (range 10.32 to 136.08) and a 3-year survival of 50%. This compares to 115 patients who underwent surgery following incomplete response to NeoCR, who had a median survival of 38.3 months (range 2.20 to 254.26) and a 3 year survival of 44%, which was statistically insignificant between the groups (p= 0.975). The overall mean survivals were 57.84 months and 57.9 months respectively. Intensive surveillance identified a cohort of patients (9% of total) with recurrence amenable to salvage surgery and with outcomes non-inferior to immediate surgery following NeoCR. As most were asymptomatic, it is suggested that without surveillance the opportunity for curative intervention would have been lost. Even novel treatments will require detection of recurrence before disease becomes unmanageable. It is suggested that surveillance guidelines be updated to standardize interval endoscopy/imaging, as for other GI malignancies.