Fruit development, from its early stages, is the result of a complex network of interacting processes, on different scales. These include cell division, cell expansion but also nutrient transport from the plant, and exchanges with the environment. In the presence of nutrient limitation, in particular, the plant reacts as a whole, by modifying its architecture, metabolism, and reproductive strategy, determining the resources available for fruit development, which in turn affects the overall source-sink balance of the system. Here, we present an integrated model of tomato that explicitly accounts for early developmental changes (from cell division to harvest), and use it to investigate the impact of water deficit and carbon limitation on nutrient fluxes and fruit growth, in both dry and fresh mass. Variability in fruit response is analyzed on two different scales: among trusses at plant level, and within cell populations at fruit level. Results show that the effect of stress on individual cells strongly depends on their age, size, and uptake capabilities, and that the timing of stress application, together with the fruit position on the plant, is crucial in determining the final phenotypic outcome. Water deficit and carbon depletion impacted either source size, source activity, or sink strength with contrasted effects on fruit growth. An important prediction of the model is the major role of symplasmic transport of carbon in the early stage of fruit development, as a catalyst for cell and fruit growth.

This work is a promising first step in the construction of a structure-function model for a plant as complex as WOSR. Once tested for other environments and/or genotypes, the model can be used for studies on WOSR architectural plasticity.

We examined 80 patients with acute obstructive anuria by ultrasound (US). Four of the 80 patients did not have dilatation of the urinary tract. In all four cases, antegrade pyelography guided by real-time US demonstrated urinary tract obstruction after the four patients had experienced 4, 5, 8, and 34 days of anuria, respectively. Diuresis occurred as a result of percutaneous nephrostomy in all four cases. Three of the patients were successfully treated by percutaneous techniques alone. Our findings demonstrate that even a complete and long-term obstruction of the urinary tract does not necessarily induce dilatation in the upper part of the tract. In such cases, only the direct opacification of the urinary tract can help confirm that the obstruction is present. Even in the absence of dilatation, antegrade pyelography guided by real-time US is a possible diagnostic method and can be the first step in the performance of percutaneous nephrostomy.

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