Dynamic Modelling by Bond Graph Approach of Convective Drying Phenomena

Drying operations play an important role in food industries. They are often the last operation of the process of manufacturing a product, with a strong influence on the final quality. The processes are numerous and depend on the type and amount of product to be dried and water to be evaporated, the desired final quality, or the desired functionality for the dried product. In this chapter, we present a modeling study of heat transfer during drying a moist agricultural product placed in a hot air flow in a tunnel dryer with partial solar heating. The bond graph approach has been used for system modeling, and it is an object-oriented graphical approach based on an energetic description between subsystems. Some drying tests have been carried out on tomatoes and the experimental results are compared with the theoretical results for the validation of the developed model

The use of water potentials in irrigation management of table grape grown under semiarid climate in Tunisia

Aim: To evaluate the usability of various plant water potentials in table grape irrigation management under a semiarid climate. Methods and results: Two water regimes were set up. The « control » water regime was the one usually used in the vineyard. The « 50 % Irrigation » water regime delivered only half the quantity of water to the vines. Predawn leaf (ψ L PD), predawn stem (ψ S PD), midday leaf (ψ L M), and midday stem (ψ S M) water potentials were measured during the growing season. The results show that the four water potentials can accurately measure the vine water status in table grape vineyard at a daily and seasonal time scale. But, ψ L M appeared to be the most reliable indicator to differentiate between the two water regimes with a frequency of 73 %. The « 50 % Irrigation » water regime induced in the ‘Italia’ cultivar an anisohydric behavior and a decrease of 29.4 % in vine vigor and 11.5 % in berry weight. Under the Tunisian climate, ‘Italia’ cultivar may exhibit night time transpiration that decreases ψ L PD by 19.5 %. Conclusion: Preliminary minimum ψ L M threshold to produce high quality table grape would be -0.8 and -1.1 MPa for pre- and post-veraison, respectively. Significance and impact of the study: The pressure chamber is an effective device for irrigation management in commercial table grape vineyards under semiarid conditions

Thermal and electrical performance evaluation of hybrid air PV/T collector – numerical analysis and experimental study

The photovoltaic-thermal (PV/T) hybrid collector is the most generative technology solar energy, which has been invented to utilise electrical energy and heat from the solar system. This paper presents a numerical analysis and experimental validation of the thermal and electrical behaviour of the air PV/T collector based on the geometric design and the Tunisia climate conditions. PV/T system has lower thermal efficiency and higher electrical efficiency (14%) at high wind speeds. To improve the thermal efficiency, a sensitivity analysis studied across a range of the air channel depth (0.01–0.08 m) with different air mass flow rate. It was concluded that the thermal energy for a PV/T air system depends on the optimal depth and variations in mass flow rate

Effet d'un support audiovisuel Allen Carr sur le comportement tabagique en milieu universitaire

Cette recherche s’intéresse à l'effet d'un support audiovisuel « Allan Carr » sur le comportement tabagique des étudiants qui le visionnent dans des conditions contrôlées, La collecte des données et leur analyse ont permis de mettre en évidence une plus grande cessation du comportement tabagique chez les sujets exposés au film thérapeutique que chez les sujets n'ayant pas subi cette condition

Benchmarking and economic analysis of the impact of geometric structural design on the thermoelectric performance of air‐cooled photovoltaic thermal systems

Abstract For a sustainable system to be designed with the lowest possible cost, photovoltaic thermal (PV/T) system efficiency and heat transmission must be increased. The performance of each hybrid PV/T air system was examined using four air PV/T models with various geometric configurations. The examination of the various mathematical models revealed how each geometry configuration affected each system's performance. Air PV/T arrangements with expanded surfaces, like fins, enhance thermoelectric performance. According to the findings, the thermal efficiencies of finned absorber PV/T and finned Tedlar PV/T are, respectively, 80.3 and 77.54%. Additionally, the figures for electrical efficiencies are 11.88 and 11.93%, respectively. For these two types of PV/T systems, the annual energy output has increased and now stands at roughly 3242 and 3316 kWh/m2, respectively. Additionally, compared to other PV/T systems, the finned Tedlar PV/T system offers higher profitability in terms of cost and revenue according to an economic research

Investigations into Physiological, Biochemical, and Histological Modifications in a Vine Decline Associated with Biotic and Abiotic Factors

Tunisian table grape production has significantly increased since two decades due to vineyards regional expansion and yield improvement. But, since several years, decline symptoms on Vitis vinifera have been recorded in some areas. A study case of a vineyard in Naassen area (near to Tunis) was chosen to investigate the disease origin and the physiological, biochemical, and histological modifications associated with vine decline. The investigation revealed characteristic symptoms on leaves, old and young shoots similar to decline symptoms of Grapevine Trunk Diseases. Based on cultural characteristics, laboratory investigations revealed the presence of Phaeomoniella chlamydospora and Phaeoacremonium spp., Diplodia seriata and Botryosphaeria dothidea, from root and shoot samples, respectively. These fungi are known as the main pathogens responsible for the Esca, Black dead arm and Excoriose. Molecular analysis confirmed the identification of Diplodia seriata. Beside morphological alterations on leaves and shoots, symptomatic vines presented significant reductions of 30 and 20% in trunk diameter and bud break rate, respectively, and delayed spring growth compared to healthy ones. Furthermore, roots and stems from declined vines contained 3 times more starch than those from asymptomatic ones. Decline survey revealed a heterogeneous dispersion of symptoms in the vineyard in accordance with water supply. The vines along the edge of vineyards are usually less watered and show more decline symptoms. Decline dynamics in time and space scales have to be considered in order to develop effective management strategies

Un exemple de l'utilisation des drones dans la gestion technique d'un verger de pêcher en Tunisie

International audienc

Spontaneous hemothorax caused by rivaroxaban treatment for pulmonary embolism: A case report

Key Clinical Message Hemothorax is a rare and potentially fatal condition characterized by pleural effusion containing over 50% of the patient's hematocrit. A massive hemothorax involves blood loss exceeding 1.5 L. Common causes include chest trauma, invasive thoracic procedures, anticoagulant medications, vascular anomalies, malignancies, and hematologic abnormalities. Spontaneous hemothorax may be seen in conjunction with pulmonary infarction and spontaneous pneumothorax. Anticoagulation is a key therapeutic strategy for certain thromboembolic events, such as pulmonary embolism. Historically, these events were treated with vitamin K antagonists (VKAs), which have demonstrated variable plasma concentrations and an increased risk of hemorrhage. With the advent of direct oral anticoagulants (DOACs), treatment has become as effective as VKAs while significantly reducing the risk of hemorrhage. However, some researchers have speculated that hemorrhagic complications in certain cases could be worse with DOACs than with VKAs. In the case presented here, we identified a genuine association between the use of rivaroxaban and spontaneous hemothorax following the initiation of treatment for pulmonary embolism