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Healthcare is expected to increasingly shift care out of inpatient settings thanks to wearable monitoring systems. Photoplethysmography (PPG) is an optical technique already integrated into wrist-worn commercial products which presents significant advantages in terms of cost and dimensions. PPG-based devices, despite their ability to detect multiple cardiovascular parameters, are affected by several influencing conditions that depend both on technological or environmental variables, and on intra- and inter-subject variability that influences the whole measurement chain and reliability, hindering an objective characterization of PPG devices. Plus, the lack of standardization for data collection and processing leads to the lack of generalizability and reproducibility of results, preventing the full exploitation of the potential prognostic capacity of this technology. Thus, this review aims not only to summarize the main influencing parameters of PPG technology, which should be addressed when testing the sensor, but also to suggest tentative guidelines for a possible future standardization initiative.

Calculating the efficiency of a solar cell depends on a precise knowledge of its area. Indeed, the photoresponse uniformity is essential to improve the manufacturing process. In this work we report on Laser Beam Induced Current measurements performed on CIG(S,Se)2 modules and Dye Sensitized Solar Cells. These measurements, performed via a green and a red HeNe lasers both operating at an optical irradiance of 1 Sun, allowed to obtain an accurate photoresponse map of the specimens and highlighted the non-uniformities with a spatial resolution of 400 μm and 80 μm, respectively.

A design and implementation of a portable functional Near InfraRed Spectroscopy embedded system prototype is described. In this theoretical and experimental work, we present an embedded system hosting 64 LED sources and 128 Silicon PhotoMultiplier detectors (SiPM). The elementary part of the structure is a flexible probe “leaf” consisting of 16 SiPMs, 4 couples of LEDs, each operating at two wavelengths, and a temperature sensor. The hardware system is based on an ARM main microcontroller that allows to perform both the switching time of LEDs and the acquisition of the SiPM outputs. The performed preliminary experimental tests achieved very promising results, thus demonstrating the effectiveness of our fNIRS system.

The extraction of biomedical parameters, for early disease detection, is assuming today an ever increasing and fundamental importance. In particular, in the cardiologic field, the preejection period (PEP) is the duration of the iso-volumetric left ventricle contraction until the aortic valve opening. This parameter is a non-constant additive delay, which rapidly changes in response to stress, emotion and physical effort. To estimate this period, several wearable electronics devices have been developed in literature, and among them the Impedance Cardiogram equipment is the most used. However, these systems are often expensive and bulky. In this paper, we propose a cost-effective and easy to employ ECG+PPG combo system able to measure pre-ejection period in a cardiac cycle. The employed system is composed of an ECG acquisition board able to host two PPG probes too.

The toxicity of dietary acrylamide (AA) depends on its biotransformation pathways, in which phase I cytochrome P-450 enzymes transform AA into glycidamide. The phase II enzyme glutathione_S_transferase (GST) catalyses the conjugation of AA with glutathione (GSH). GST induction by phytochemicals like sulforaphane (SFN) plays a role in chemoprevention. Here, the effect of SFN on the detoxification of AA through GSH conjugation was studied in Caco-2 cells. GSH adducts with AA and SFN were synthesized, identified by NMR and quantified by LC-MS/MS. Caco-2 cells were treated with either 2.5 mM AA, 10 mu M SFN or the combination of both for 24 h. Concentrations of GSH conjugates (GSH-AA, GSH-SFN, SFN-GSH-AA), AA and SFN were analysed by LC-MS/MS. GSH contents and GST activity were determined photometrically. GST activity was increased after treatment of the cells with SFN (38 +/- 6%, p

Sulphur is essential in the biosynthesis of secondary metabolites with high nutritional value that typically accumulate in Brassica species. Among these, glucosinolates are the most representative. The level of glucosinolates in these plants is highly dependent on genetic factors as well as environmental determinants, such as the available soil sulphur content. There is an increasing need of defining the metabolic profile of Brassica species in response to both cultivation practices and environmental factors since a targeted modification of its constituents may significantly affect the functional properties and the commercial value of these vegetables. Here, we report on the effects of sulphur fertilization on flavonols, phenolic acids and glucosinolates contents of two friariello (Brassica rapa L. subsp. sylvestris L. Janch. var. esculenta Hort.) ecotypes—Lingua di Cane and Sorrentino. Friariello quality in terms of sprouts plus inflorescence nitrate and chlorophyll contents was also assessed. We found a significantly higher flavonols content in the ecotype Sorrentino, whereas its glucosinolates level was relatively smaller compared to Lingua di Cane. Sulphur fertilization significantly improved the antioxidant activity of both ecotypes and was associated with a genotype-dependent significant reduction of leaf nitrate content.

In earlier experiments, the MDR (multidrug resistance)-reversal activities of Anastasia Black (Russian black sweet pepper) extracts had been analysed. Recently, the most effective MDR reversing extracts and fractions have been separated by HPLC (high-performance liquid chromatography, for carotenoids) and LC-MS-MS (HPLC combined with mass spectrometry, for phenolic compounds) methods. As a result of the analytical studies, the following flavonoids had been identified: feruloyl glucopyranoside, quercetin rhamnopyranoside glucopyranoside, luteolin glucopyranoside arabinopyranoside, apigenin glucopyranoside arabinopyranoside, quercetin rhamnopyranoside, luteolin arabinopyranoside diglucopy-ranoside, hesperidine and luteolin glucuronide. According to the literature, the aglycones of these phenolic compounds exhibit MDR-reversal activity in vitro, and the connection between the phenolic content of Anastasia Black and MDR-reversal action was therefore studied by different analytical methods The results of this study revealed that the identified flavonoids of Anastasia Black may be only partially responsible for the modulation of the MDR of mouse lymphoma cells. Other lipophilic compounds, most probably carotenoids, present in Russian black sweet pepper may act as inhibitors of MDR reversal.

We present a method to analyze the dynamics of physiological networks beyond the framework of pairwise interactions. Our method defines the so-called O-information rate (OIR) as a measure of the higher-order interaction among several physiological variables. The OIR measure is computed from the vector autoregressive representation of multiple time series, and is applied to the network formed by heart period, systolic and diastolic arterial pressure, respiration and cerebral blood flow variability series measured in healthy subjects at rest and after head-up tilt. Our results document that cardiovascular, cerebrovascular and respiratory interactions are highly redundant, and that redundancy is enhanced by the entrainment of cardiovascular and cerebrovascular oscillations and by sympathetic activation.