Inferring possible magnetic field strength of accreting inflows in EXor-type objects from scaled laboratory experiments

Aims. EXor-type objects are protostars that display powerful UV-optical outbursts caused by intermittent and powerful events of magnetospheric accretion. These objects are not yet well investigated and are quite difficult to characterize. Several parameters, such as plasma stream velocities, characteristic densities, and temperatures, can be retrieved from present observations. As of yet, however, there is no information about the magnetic field values and the exact underlying accretion scenario is also under discussion. Methods. We use laboratory plasmas, created by a high power laser impacting a solid target or by a plasma gun injector, and make these plasmas propagate perpendicularly to a strong external magnetic field. The propagating plasmas are found to be well scaled to the presently inferred parameters of EXor-type accretion event, thus allowing us to study the behaviour of such episodic accretion processes in scaled conditions. Results. We propose a scenario of additional matter accretion in the equatorial plane, which claims to explain the increased accretion rates of the EXor objects, supported by the experimental demonstration of effective plasma propagation across the magnetic field. In particular, our laboratory investigation allows us to determine that the field strength in the accretion stream of EXor objects, in a position intermediate between the truncation radius and the stellar surface, should be of the order of 100 G. This, in turn, suggests a field strength of a few kilogausses on the stellar surface, which is similar to values inferred from observations of classical T Tauri stars

Functional outcome and muscle wasting in adults with tetanus.

BACKGROUND: In many countries, in-hospital survival from tetanus is increasing, but long-term outcome is unknown. In high-income settings, critical illness is associated with muscle wasting and poor functional outcome, but there are few data from resource-limited settings. In this study we aimed to assess muscle wasting and long-term functional outcome in adults with tetanus. METHODS: In a prospective observational study involving 80 adults with tetanus, sequential rectus femoris ultrasound measurements were made at admission, 7 days, 14 days and hospital discharge. Functional outcome was assessed at hospital discharge using the Timed Up and Go test, Clinical Frailty Score, Barthel Index and RAND 36-item Short Form Health Survey (SF-36) and 3 and 6 months after discharge using the SF-36 and Barthel Index. RESULTS: Significant muscle wasting occurred between hospital admission and discharge (p70 y of age, functional recovery at 6 months was reduced compared with younger patients. Hospital-acquired infection and age were risk factors for muscle wasting. CONCLUSIONS: Significant muscle wasting during hospitalization occurred in patients with tetanus, the extent of which correlates with functional outcome

Factors influencing physical activity and rehabilitation in survivors of critical illness: a systematic review of quantitative and qualitative studies

PURPOSE: To identify, evaluate and synthesise studies examining the barriers and enablers for survivors of critical illness to participate in physical activity in the ICU and post-ICU settings from the perspective of patients, caregivers and healthcare providers. METHODS: Systematic review of articles using five electronic databases: MEDLINE, CINAHL, EMBASE, Cochrane Library, Scopus. Quantitative and qualitative studies that were published in English in a peer-reviewed journal and assessed barriers or enablers for survivors of critical illness to perform physical activity were included. Prospero ID: CRD42016035454. RESULTS: Eighty-nine papers were included. Five major themes and 28 sub-themes were identified, encompassing: (1) patient physical and psychological capability to perform physical activity, including delirium, sedation, illness severity, comorbidities, weakness, anxiety, confidence and motivation; (2) safety influences, including physiological stability and concern for lines, e.g. risk of dislodgement; (3) culture and team influences, including leadership, interprofessional communication, administrative buy-in, clinician expertise and knowledge; (4) motivation and beliefs regarding the benefits/risks; and (5) environmental influences, including funding, access to rehabilitation programs, staffing and equipment. CONCLUSIONS: The main barriers identified were patient physical and psychological capability to perform physical activity, safety concerns, lack of leadership and ICU culture of mobility, lack of interprofessional communication, expertise and knowledge, and lack of staffing/equipment and funding to provide rehabilitation programs. Barriers and enablers are multidimensional and span diverse factors. The majority of these barriers are modifiable and can be targeted in future clinical practice

Whistler Waves' Propagation in Plasmas With Systems of Small-Scale Density Irregularities: Numerical Simulations and Theory

International audienceThe propagation of whistler waves in a magnetized plasma containingmultiple small-scale (100 m to 1 km) field-aligned irregularities ofenhanced electron density is considered analytically and by means ofnumerical simulations. Such systems of irregularities can develop in theupper ionosphere during the generation of density ducts by high-frequency heating facilities and other types of active experiments. Thesimulation parameters are close to those of an active experiment where awhistler wave of 18 kHz emitted by a ground-based very low frequency(VLF) transmitter was received onboard the DEMETER satellite at 700 kmabove the SURA heater. The study reveals a number of remarkableproperties of the VLF waves' propagation, including the existence ofspecific waveguide modes of the small-scale density structures and of acharacteristic transverse size d0 of the irregularities.Irregularities with small density enhancements around 10-20% andtransverse sizes larger than d0?1 km can serve as separatewaveguides for VLF waves. In their turn, single irregularities narrowerthan d0 cannot be considered as individual ductingstructures. Numerical simulations show that, for the analysis of theelectromagnetic whistlers' propagation, a system of closely spacedirregularities with scales narrower than d0 can be modeled byan equivalent ducting structure with a smoothed density profile. Suchequivalent structure has the same ducting properties for whistlers andcan be produced by averaging with a sliding window of a scale aboutd0 the original density distribution

ANALYSIS OF THE ADHESION OF MICROORGANISMS TO MODERN BASIC MATERIALS IN PROSTHETIC DENTISTRY

Aim. The research was conducted for the study of the adhesion of samples of the domestic modern photopolymerizable base composite material in comparison with other materials for the manufacture of the denture bases.Materials and methods. Five samples of the materials were tested to conduct a microbiological study on the subject of primary adhesion of microorganisms to the surface of the base materials. The adhesion of microorganisms to the samples of the base composite materials was assessed using the index method.Results. As a result of a laboratory research, it can be concluded that the new photopolymerization material «Sample 1» used for the manufacture of the bases for the removable dentures has 1, 19 times lower adhesive activity to the colonyforming Prevotella intermedia microorganisms and Candida krusei mushrooms in comparison with the acrylic plastics and thermoplastic materials «Sample 2»; 1,14 times in comparison with the nylon material «Sample 3» and with the monomer material «Sample 4» with a statistically reliable variable number. It should be noted that the Axil-LC topcoat varnish supplied with the Sample 1 basic material kit increases microbial adhesion by 1.36 times.Conclusion. The adhesion of microorganisms to the materials that are used in dental practice is due to the surface tension coefficient – the greater the surface tension coefficient, the higher the probability of adhesion of microorganisms on the surface of these materials. The investigated new photopolymerization material «Sample 1» without coating with a protective varnish showed low adhesion to all major pathogens. Covering with a protective lacquer design, which is a part of the set of the material, significantly increases the adhesion of microorganisms on the surface of the material. The established indexes of microorganisms adhesion to the material «Sample 1» allow us to recommend it for the manufacture of bases for temporary dentures and immediate dentures in the treatment at the stages of dental implantation

Fine structure of density ducts formed by active radiofrequency action on laboratory and space plasmas

© 2015, Pleiades Publishing, Inc. The results of active ionospheric and model laboratory experiments on the generation of artificial irregularities of a magnetized plasma (density ducts), which can be used as waveguide channels for low-frequency waves, have been reported. It has been found that ducts formed at the localized high-frequency heating of the plasma have a fine structure under certain conditions: they include irregularities of the plasma density, which significantly affect the propagation of low-frequency waves, ensuring the deep amplitude modulation of low-frequency radiation and changing its spatial structure. A mechanism of the formation of such irregularities has been proposed