ABSTRACT
This article discusses the use of a handheld electronic nose to obtain information on the presence of some aromatic defects in natural cork stoppers, such as haloanisoles, alkylmethoxypyrazines, and ketones. Typical concentrations of these compounds (from 5 to 120 ng in the cork samples) have been measured. Two electronic nose prototypes have been developed as an instrumentation system comprise of eight commercial gas sensors to perform two sets of experiments. In the first experiment, a quantitative approach was used whist in the second experiment a qualitative one was used. Machine learning algorithms such as k-nearest neighbors and artificial neural networks have been used in order to test the performance of the system to detect cork defects. The use of this system tries to improve the current aromatic defect detection process in the cork stopper industry, which is done by gas chromatography or human test panels. We found this electronic nose to have near 100 % accuracy in the detection of these defects.
Subject(s)
Electronic Nose , Industry , HumansABSTRACT
This work presents the development of tin oxide nanofibers (NFs) and nanoribbons (NRs) sensors with graphene as a dopant for the detection of volatile organic compounds (VOCs) corresponding to different chronic diseases (asthma, chronic obstructive pulmonary disease, cystic fibrosis or diabetes). This research aims to determine the ability of these sensors to differentiate between gas samples corresponding to healthy people and patients with a disease. The nanostructures were grown by electrospinning and deposited on silicon substrates with micro-heaters integrated. The morphology of NFs and NRs was characterized by Scanning Electron Microscopy (SEM). A gas line was assembled and programmed to measure a wide range of gases (ethanol, acetone, NO and CO) at different concentrations simulating human breath conditions. Measurements were made in the presence and absence of humidity to evaluate its effect. The sensors were able to differentiate between the concentrations corresponding to a healthy person and a patient with one of the selected diseases. These were sensitive to biomarkers such as acetone and ethanol at low operating temperatures (with responses above 35%). Furthermore, CO and NO response was at high temperatures (above 5%). The sensors had a rapid response, with times of 50 s and recovery periods of about 10 min.
Subject(s)
Breath Tests , Graphite , Nanofibers , Nanotubes, Carbon , Tin Compounds , Volatile Organic Compounds/analysis , Biomarkers/analysis , Gases/analysis , HumansABSTRACT
Vascular lesions constitute a widely heterogeneous group of tumors and malformations. For head and neck vascular anomalies, most studies have not attempted to make the differential diagnosis between true hemangiomas and vascular malformations, because an accurate diagnosis remains a challenge for physicians. The successful treatment of vascular anomalies depends on a profound knowledge of their biologic behavior and correct classification. Recently, specific immunohistochemical markers such as erythrocyte-type glucose transporter protein 1 have been described to differentiate hemangiomas from vascular malformations. This report describes 2 cases of intramuscular vascular anomalies involving the masseter muscle histologically diagnosed primarily as cavernous hemangiomas and presents the imaging and pathologic findings. Ample surgical excision was performed through an intraoral approach. Immunohistochemistry showed no uptake of glucose transporter protein 1. The literature was reviewed and the designation intramasseteric vascular malformation for this entity is proposed.
Subject(s)
Glucose Transporter Type 1/analysis , Masseter Muscle/blood supply , Muscle Neoplasms/diagnosis , Vascular Malformations/diagnosis , Biomarkers/analysis , Capillaries/pathology , Diagnosis, Differential , Female , Fibrosis , Hemangioma/diagnosis , Hemangioma, Cavernous/diagnosis , Humans , Hypertrophy , Male , Masseter Muscle/pathology , Middle Aged , Muscle, Smooth, Vascular/pathology , Young AdultABSTRACT
En un intento por establecer criterios pronósticos accesibles que pudieran precedir gravedad y mortalidad en los enfermos con pancreatitis aguda, se analizaron los expedientes completos de 45 enfermos con un primer episodio de pancreatitis, 12 de ellos con la forma grave (necrótica y/o hemorrágica), 6 de los cuales fallecieron. Se clasificaron en grupos y subgrupos de acuerdo a su gravedad y mortalidad respectivamente analizando 24 parámetros al ingreso del enfermo y 17 en la evolución de las primeras 48 horas. Los resultados fueron analizados con la prueba de la "t" de Student y análisis de varianza con dos criterios de clasificación; de esta manera fue posible identificar 10 (indicadores) al ingreso y 12 en las primeras 48 horas que fueron estadísticamente más frecuentes en los enfermos con la forma grave; el número de criterios positivos fue útil para determinar gravedad, pero no mortalidad en el grupo de enfermos graves. Se establecen consideraciones acerca de estos criterios, recordando que deben ser utilizados para evaluar diferentes modalidades terapéuticas de manera uniforme y para vigilar más estrechamente a los enfermos con mayor riesgo de morir por este padecimiento
