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This paper presents a novel system for generating and receiving quasi-continuous (QC) TeraHertz (THz) waves. A system design and theoretical foundation for QC-THz signal generation are presented. The proposed QC-THz system consists of commercially available photo-conductive antennas used for transmission and reception of THz waves and a custom-designed QC optical signal generator, which is based on a fast optical frequency sweep of a single telecom distributed-feedback laser diode and unbalanced optical fiber Michelson interferometer used for a high-frequency modulation. The theoretical model for the proposed system is presented and experimentally evaluated. The experimental results were compared to the state-of-the-art continuous-wave THz system. The comparison between the continuous-wave THz system and the proposed QC-THz system showed the ability to transmit and receive QC-THz waves up to 300 GHz. The upper-frequency limit is bounded by the length of the used Michelson interferometer. The presented design of THz signal generation has a potential for industrial application because it is cost-efficient and can be built using commercially available components.

This paper presents an automatic classification of plastic material's inorganic pigment using terahertz spectroscopy and convolutional neural networks (CNN). The plastic materials were placed between the THz transmitter and receiver, and the acquired THz signals were classified using a supervised learning approach. A THz frequency band between 0.1-1.2 THz produced a one-dimensional (1D) vector that is almost impossible to classify directly using supervised learning. This paper proposes a novel pre-processing of 1D THz data that transforms 1D data into 2D data, which are processed efficiently using a convolutional neural network. The proposed pre-processing algorithm consists of four steps: peak detection, envelope extraction, and a down-sampling procedure. The last main step introduces the windowing with spectrum dilatation that reorders 1D data into 2D data that can be considered as an image. The spectrum dilation techniques ensure the classifier's robustness by suppressing measurement bias, reducing the complexity of the THz dataset with negligible loss of accuracy, and speeding up the network classification. The experimental results showed that the proposed approach achieved high accuracy using a CNN classifier, and outperforms 1D classification of THz data using support vector machine, naive Bayes, and other popular classification algorithms.

We report 64-year old patient who was admitted in ICU with left side ileofemoral thrombosis and splenic abscess during Salmonella enteritidis infection.

Cardiogenic shock is the most important fatal complication of acute myocardial infarction (AMI). This syndrome may be considered as a severe form of left ventricular failure and the mortality rate is very high. According to the clinical classification, Killip class IV ranges from 60 to 95%, depending on authors. Shock occurs in about 15-20% of patients with AMI and accounts for at least 70% of the in-hospital deaths. During 1994, 168 patients with AMI were treated at the Intensive Care Unit of the Zagreb General Hospital, of which 14 (8.2%) developed cardiogenic shock. Ten patients experienced the first myocardial infarction, and 4 were admitted because of the second myocardial infarction, that time of anterior localization. Signs of cardiogenic shock were present in 8 (57.1%) patients already on admission. Three patients developed cardiogenic shock during the first 10 hours of hospitalization and further 3 patients during the initial 4 to 15 days of treatment. Older age prevailed. Eleven (78.5%) persons were older than 60 years of age. Eight patients demonstrated anterior infarction, 4 had inferior infarction and 2 non-Q-wave infraction. All patients had signs of left ventricular failure evidenced by pulmonary edema (Killip class IV) and later complicated by arrhythmia. Of the 14 patients who had AMI with the shock syndrome, 13 (92.8%) died; 5 (35.7%) patients during the first 2 hours, 3 (21.4%) within 24 hours of infarction, and 5 (35.7%) patients during the initial 4 to 25 days of treatment. Patients were treated conservatively, and only 3 patients received thrombolytic therapy, namely, streptokinase.