ThermoSteg-Covert Channel for Microbolometer Thermographic Cameras

The article presents a new concept—steganography in thermography. Steganography is a technique of hiding information in a non-obvious way and belongs to sciences related to information security. The proposed method, called ThermoSteg, uses a modification of one of the parameters of the thermal imaging camera—integration time—to embed the signal containing hidden information. Integration time changing makes the microbolometer array heat up while reading the sensors. The covert information can be extracted from the stream of thermograms recorded by another thermal camera that observes the first one. The covert channel created with the ThermoSteg method allows the transmission of covert data using a thermal sensor as a wireless data transmitter. This article describes a physical phenomenon that is exploited by the ThermoSteg method and two proposed methods of covert data extraction, and presents the results of experiments.

Impact of inhalers used in the treatment of respiratory diseases on global warming

The term "carbon footprint" describes the emission of greenhouse gases into the environment as a result of human activities. The healthcare sector is responsible for 5-8% of the value of global greenhouse gas emissions, of which medical aerosols account for only 0.03% of the total emissions. The reduction of greenhouse gases, including those used for the production and use of medicinal products and medical devices, is part of the responsibilities that Poland and the respective countries should undertake in order to implement the assumptions of international law. At the level of medical law, this obligation correlates with the need to exercise due diligence in the process of providing health services, including the selection of low-emission medical products and devices (inhalers) and providing patients with information on how to handle used products and devices, with particular emphasis on those that imply greenhouse gas emissions. Pressurized metered dose inhalers (pMDI) containing the hydrofluoroalkane 134a demonstrate the largest carbon footprint, followed by a metered dose liquid inhaler and dry powder inhalers (DPI). The carbon footprint of DPI with a given drug is 13-32 times lower than it is in the case of the corresponding pMDI. Replacement of pMDI by DPI is one of the effective methods to reduce the carbon footprint of inhalers, and the replacement should be based on current medical knowledge. A recycling system for all types of inhalers must be urgently implemented.

Femtosecond fiber lasers with pulse energies above 10 nJ

A series of experiments aimed at determining the maximum pulse energy that can be produced by a femtosecond fiber laser is reported. Exploiting modes of pulse propagation that avoid wave breaking in a Yb fiber laser allows pulse energies up to 14 nJ to be achieved. The pulses can be dechirped to sub-100-fs duration to produce peak powers that reach 100 kW. The limitations to the maximum pulse energy are discussed.

High-energy femtosecond stretched-pulse fiber laser with a nonlinear optical loop mirror

A stretched-pulse fiber laser with a nonlinear optical loop mirror (NOLM) that produces 100-fs pulses with 1-nJ energy is demonstrated. These results constitute a 30-fold increase in pulse energy over previously reported femtosecond fiber lasers with a NOLM. Compared with previous stretched-pulse lasers, this laser offers a cleaner spectrum and improved stability, with comparable pulse duration and energy. Implications for the construction of truly environmentally stable lasers are discussed.

Churg-Strauss syndrome leading to small bowel infarction: an unusual case of abdominal pain in a young patient

A 33-year-old man with a history of severe asthma presented to the emergency department with a week-long history of severe unrelenting abdominal pain, nausea and decreased appetite. He was admitted to hospital, and routine gastrointestinal investigations were performed, which did not elucidate the cause of his abdominal pain. Exploratory laparotomy demonstrated patchy infarction of the entire small bowel, characteristic of Churg-Strauss syndrome. The patient subsequently underwent 12 separate laparotomies to salvage surviving small bowel. The patient is maintained on total parenteral nutrition.

Patterns of practice in emergency department management of chest pain of suspected cardiac origin: clinical utility of single stat creatine kinase (CK)

The patterns of practice and the clinical utility of a single stat creatine kinase (CK) level in the emergency department management of chest pain of suspected cardiac origin were examined by a prospective observational study using a two-part questionnaire, completed by physicians before and after availability of CK results. The results showed that of the 776 patients in the study, 135 were admitted to hospital with acute myocardial infarction (AMI), 285 were admitted for reasons other than AMI, 343 were discharged, and 13 died or were transferred to another hospital. Although initial and final diagnoses in the emergency department did not differ in 597 patients (77%), initial decisions to admit or discharge were made in only 244 (31%) patients without waiting for CK results, and in 401 (52%) cases, decisions on patient disposition were deferred. Of 218 patients who had elevated CK levels, 193 (89%) were admitted, 121 for AMI. Only five (< 1%) patients who would otherwise have been discharged were admitted because of elevated CK levels. Of the 343 discharges, 245 (71%) occurred after the physicians knew the CK results. It is concluded that emergency department physicians routinely make changes in their diagnostic and management decisions based on current information and as it becomes updated. This study also suggests that there appears to be a heavy reliance on a single CK assay, although the relative importance of this diagnostic test compared to other factors is not known. Further studies are necessary.

Active-passive coping and skin conductance and heart rate changes

Sixty subjects were administered 33 tasks, selected from the Raven Progressive Matrices, in conditions that differed by type of monetary reinforcement (reward, frustration, and control group). Subjects were tested in pairs. One subject, assigned as the active one, was asked to solve a problem while the other was only a passive observer. Heart rate level and the amplitude of evoked skin conductance responses were measured. Statistical analysis detected a higher heart rate level in active versus passive subjects at the beginning stage of the experiment, as well as a faster heart rate decrease in the former versus the latter group during subsequent blocks of four tasks. Changes in skin conductance response magnitude during the ensuing task phases exhibited a descending trend in passive subjects and an ascending trend in active subjects. The monetary reinforcement manipulation was not effective. The results support a concept put forward by Fowles (1988), who maintained that tonic heart rate and skin conductance response amplitude may serve as indices of the behavioral activation system and behavioral inhibition system, respectively, as postulated by Gray's model of arousal.

Sources of uncertainty and psychophysiological state changes under conditions of noxious stimulus anticipation

The main aim of the experiment was to compare the effect of the two variables (regarded here as different sources of subjective uncertainty) - probability of stimulus occurrence and ambiguity of the message about this probability - upon changes in heart rate (HR) and skin resistance (SR) during anticipation of a noxious stimulus. Three other independent variables - the type of stimulus (shock vs. sound), repetition of trials (two series of trials), and time-within-trial - were controlled as well. Results indicate that ambiguity as compared to probability has a more pronounced effect upon SR changes. Effects of the two variables upon HR changes are not significant. Moreover, in the shock group, the effect of repetition of trials was found to have a habituation effect for HR changes and a dishabituation effect for SR changes.