In the search for non-chemical and green methods to counteract the bacterial contamination of foods, the use of natural substances with antimicrobial properties and light irradiation at proper light waves has been extensively investigated. In particular, the combination of both techniques, called photodynamic inactivation (PDI), is based on the fact that some natural substances act as photosensitizers, i.e., produce bioactive effects under irradiation. Notably, curcumin is a potent natural antibacterial and effective photosensitizer that is able to induce photodynamic activation in the visible light range (specifically for blue light). Some practical applications have been investigated with particular reference to food preservation from bacterial contaminants.

Quantitative assessment of force in masticatory muscles is not a routine clinical test, probably due to the lack of an “easy-to-use” device. Aim of this study is (1) to present a low cost bite force instrument located in a custom-made housing, designed to guarantee a comfortable and effective bite action, (2) to evaluate its mechanical characteristics, in order to implement it in clinical settings and in experimental setups. Linearity, repeatability and adaptation over time were assessed on a set of four different sensors in bare and housed condition. Application of the housing to the transducer may appreciably alter the transducer's response. Calibration of the housed transducer is thus necessary in order to correctly record real bite force. This solution may represent a low cost and reliable option for biting force measurement and objective assessment of individual force control in the scientific and clinical setting

Intermittent Pneumatic Compression (IPC) devices can be used to analyze the mechanisms underlying several vascular phenomena, such as hyperaemia. Commercial devices have limited dynamics and do not allow the delivery of customizable compressive pressure patterns, making difficult the analysis of such phenomena, which may require the application of long stimulations with low amplitude as well as fast compressions with higher pressure level. To overcome these issues, a novel pneumo-tronic device aimed to the investigation of the physiological effects induced by limb compressions has been conceived and is presented in this work. The design requirements of the system, capable of delivering customizable compressive patterns in the range 0-200 mmHg, are outlined. The final prototype architecture is described, and a mathematical model of the entire system, also including the interaction between the device and the limb tissues, is proposed. The performance of the device has been evaluated in several conditions by means of simulations, whose results have been compared to the data collected from experimental trials in order to validate the model. The outcomes of both experimentation and simulation trials proved the effectiveness of the solution proposed. A possible employment of this device for the investigation of the rapid compression-induced hyperaemia is presented. Other potential applications concern the wide range of intermittent-pneumatic compression treatments.

ObjectiveCommercial devices for pneumatic compressive treatment of the limbs generally provide predefined stereotyped compressive profiles. The possibility to deliver compressive stimuli with a customizable pressure profile would be useful to differently probe the vascular reactivity to muscle compression (MC) and improve the understanding of MC-induced hyperemia. Aim of this study was the realization of a novel pneumatic system capable of generating adjustable and stable compressive conditions, preceding and following a "standard" MC stimulus Approach A custom-made pneumatic system specifically built to this purpose is tested and characterized in 10 subjects.Three different compressive patterns were delivered to the leg: 1) a constant level: 50 mmHg for 50 s; 2) MC: 200 mmHg for 1 s; 3) a complex profile: 20 mmHg for 50 s, 200 mmHg for 1 s, 50 mmHg for 50 s. Main resultsThe implemented system allowed to deliver graded compressions to the limb characterized by fast transitions (0 to 200 mmHg in 0.5 ± 0.07 s) and stable plateau levels (50.4 ± 0.5 mmHg). SignificanceA new, low-cost, pneumatic prototype has been presented and tested in the present study allowing to deliver compressive stimuli with pre-and post-compressions of adjustable level. This device has been conceived for research purposes and may find application in therapeutic compressive treatments.

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