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Breast cancer is a very important health concern around the world. Early detection of such a disease increases the chances of survival. Among the available screening tools, there is the Electro-Impedance Mammography (EIM), which is a novel and less invasive method that captures the potential difference stored in breast tissues under the assumption that electrical properties among normal and pathologically altered tissues are different. In this paper, we address breast cancer detection as a multi-class problem aiming to determine the corresponding label in terms of the Breast Imaging Electrical Impedance classification system, the standard used by physicians for interpreting an EIM mammogram. For experimental purposes, for the first time in the literature, we took advantage of a dataset comprising EIM of Mexican patients. Aiming to establish a baseline for this task, traditional supervised learning methods were used together with two different feature extraction techniques: raw pixel data and transfer learning. Besides, data augmentation was exploited for compensating data imbalance. Different experimental settings were evaluated reaching classification rates over 0.85 in F-score. KNN emerges as a very promising classifier for addressing this task. The obtained results allow us to validate the usefulness of traditional methods for classifying electro-impedance mammograms. [ABSTRACT FROM AUTHOR]

In order to gain knowledge on the potential use of Helianthus annuus L. for the remediation of Cr(VI) polluted waters, hydroponics experiments were set up to determine Cr uptake and tolerance in different Cr(VI)-sulfate conditions, and Cr biotransformations. Results indicated that Cr(VI) promoted seed germination, and plant tolerance was higher at younger plant stages. Cr uptake was dependent on sulfate concentrations. The highest Cr levels in roots and shoots (13,700 and 2,500 mg kg–1dry weight (DW), respectively) were obtained in 1 mM sulfate. The lowest Cr uptake in roots (10,600 mg kg–1DW) was observed in seedlings treated with no sulfate. In shoots, Cr concentration was of 1,500 mg kg–1DW for the 1 mM sulfate treatment, indicating a different level of interaction between chromate and sulfate in both tissues. For the first time, using micro X-ray florescence (μXRF), we demonstrated Cr reaches the root stele and is located in the walls of xylem vessels. Bulk and micro X-ray Absorption Near-Edge Structure (μXANES) results showed that Cr in the roots is mostly in the form of Cr(III) phosphate (80%), with the remainder complexed to organic acids. Our results suggest this plant species may serve for Cr(VI) rhizofiltration purposes. [ABSTRACT FROM AUTHOR]

Background/aims: evidence of gender-related differences in gastric emptying have been reported in the literature. Usually, those researches have focusing only with solid or liquid meal and invasive techniques. The objective of this study was to know the differences in the half time of gastric emptying and frequency of peristaltic contractions measured with magnetogastrography (MGG) on healthy subjects, using a semi-solid test meal., Methods: the study was carried out in 16 healthy subjects without gastrointestinal disease history they were divided in two groups, 8 male and 8 female. A test meal composed by 250 ml of yogurt and 3 grs of magnetite (Fe3O4), was employed., Results: the gastric emptying half times were found to be 32.3 +/- 10.8 and 36.0 +/- 6.7 minutes, for men and women, respectively. Magnetogastrography modality presented in this study is a useful technique to measure the gastric emptying and the peristaltic contractions frequency. The studies were performed in healthy subjects without side effects. Using this technique a significant statistical difference (p<0.05) on gastric emptying from healthy volunteers was obtained between men and women., Conclusions: a contribution of this study was to demonstrate the feasibility of magnetogastrography to analyze gender differences in the gastric emptying half time using a semi-solid test meal.

A noninvasive, sensitive, and specific method of detecting mesenteric ischemia would be of great use in reducing the morbidity and mortality with which it is associated. Acute lesions in polarized electrically coupled tissues lead to injury currents driven by the transmembrane resting potential gradient. These injury currents are an effective indicator of pathophysiology. The presence of near-DC injury currents in rabbit intestinal smooth muscle has already been demonstrated using a Superconducting quantum interference device (SQUID), and the aim of this study was to evaluate the effect of arterial reperfusion upon these currents. We exteriorized the small bowel of 14 New Zealand white rabbits and placed a remotely operated vascular occluder around the distal most artery supplying a 3-in segment of the jejunum. Experiments were conducted in three groups, i.e., control (n=3), ischemia (n=6), and reperfusion following ischemia (n=5). The subject's position was modulated in and out of the biological field detection range of a SQUID magnetometer using a lift constructed of nonmagnetic material. The changes in magnetic field amplitude were 9.3 and 31.01% for the control and ischemia groups, respectively. The reperfusion group first exhibited a decrease of 17.35% from the pre-ischemic to the ischemic period, followed by an increase of 13.88% of the ischemic value after reestablishing perfusion. In conclusion, injury currents in GI smooth muscle that appear during ischemia are reduced to near-pre-ischemic levels during reperfusion.