Point-of-care ultrasonography—An essential skill for medical graduates?

The recent proliferation of point-of-care ultrasonography (POCUS) in the clinical practice of many medical specialties has exposed persistent barriers to education, training and standardisation. Specialist training curriculums are already overwhelming, having grossly insufficient time available for the specialist trainees and for the small number of available trainers alike to incorporate POCUS into postgraduate education. The logical solution to overcome these barriers could be to incorporate basic POCUS education and training into the undergraduate university curriculums, introducing longitudinal integration with other relevant medical sciences. The Australasian Society of Ultrasound in Medicine already has well-established educational programmes in POCUS with standardised assessment of competency, which could potentially offer the basis for symbiosis with the Australian and New Zealand medical schools

Hydrogeoecological estimation of the fresh waters state of the Nadym-Pursk and Pur-Taz oil and gas provinces of the Yamal-Nenets Autonomous District in connection with intensive mining of hydrocarbon deposits

In recent years the problem of rational use and protection of the country’s groundwater resources has become increasingly important. This is due to want of reserves of groundwater and surface water, their depletion with technological progress and the ever increasing influence of human economic activity. The growth of cities, industry, expansion of water consumption for various economic needs significantly change the water balance regimes on the surface, in soils and rocks.The northern part of the West Siberian Artesian Megabasin (WSAMB) is located on the territory of the Yamal-Nenets Autonomous District (YNAD). Now the district is an intensively developing region of the Russian Federation. Here, oil and gas are extracted, large transport communications and residential areas are located. The district is characterized by extreme landscape, climatic and geoecological conditions that determine the nature of development of dangerous natural processes, the interaction of surface and groundwater and the migration of pollutants. The anthropogenic impact on the fresh groundwater of WSAMB and the increase in the residential load in the developed territories, which is intensified as a result of oil and gas production, requires an in-depth study of the regional hydrodynamics of the Upper Eocene Quaternary hydro-geological complex.The article provides calculations of mass flows of the main pollutants in groundwater and provides a preliminary forecast of the possible change in the quality of fresh water under the influence of anthropogenic factor

Современные нозоареалы клещевого энцефалита и клещевого риккетсиоза в Сибири

Natural centers of tick-borne encephalitis and tick-borne rickettsiosis diseases are distinguished not only by stability and in- creasing level of epidemiological manifestation but also by ability to enlargement of areas. It is found that a contribution of some regions of Russia to the sick rate of tick-borne encephalitis and tick-borne rickettsiosis is changing in time. For tick-borne encephalitis the contribution of East Siberia increases and becomes equal to one of Ural area. For tick-borne rickettsiosis the general contribution of four regions (East Siberia, West Siberia, Ural and Far East) amount to 92% of diseases in country. The greater part of tick-borne rickettsiosis diseases (62,1%) is the contribution of East Siberia because of activi- ty of disease centers of Altai area.Природные очаги клещевого энцефалита (КЭ) и клещевого риккетсиоза (КР) отличаются не только стойкостью и воз- растающим уровнем эпидемического проявления, но и способностью к расширению ареалов. Установлено, что долевое значение отдельных регионов России в заболеваемости КЭ и КР с течением времени изме- няется. При КЭ непрерывно возрастает доля Восточной Сибири, приравниваясь к уровню Урала. На четыре региона — За- падную и Восточную Сибирь, Урал и Дальний Восток — приходилось до 92% всех заболеваний КЭ в стране. Основная часть заболеваний КР приходится на Западную Сибирь за счет высокой активности очагов в Алтайском крае

Splitting the anterior mitral leaflet impairs left ventricular function in an ovine model

OBJECTIVES: During mitral valve replacement, the anterior mitral leaflet is usually resected or modified. Anterior leaflet splitting seems the least disruptive modification. Reattachment of the modified leaflet to the annulus reduces the annulopapillary distance. The goal of this study was to quantify the acute effects on left ventricular function of splitting the anterior mitral leaflet and shortening the annulopapillary distance. METHODS: In 6 adult sheep, a wire was placed around the anterior leaflet and exteriorized through the left ventricular wall to enable splitting the leaflet in the beating heart. Releasable snares to reduce annulopapillary distance were likewise positioned and exteriorized. A mechanical mitral prosthesis was inserted to prevent mitral incompetence during external manipulations of the native valve. Instantaneous changes in left ventricular function were recorded before and after shortening the annulopapillary distance, then before and after splitting the anterior leaflet. RESULTS: After splitting the anterior leaflet, preload recruitable stroke work, stroke work, stroke volume, cardiac output, left ventricular end systolic pressure and mean pressure were significantly decreased by 26%, 23%, 12%, 9%, 15% and 11%, respectively. Shortening the annulopapillary distance was associated with significant decreases in the end systolic pressure volume relationship, preload recruitable stroke work, stroke work and left ventricular end systolic pressure by 67%, 33%, 15% and 13%, respectively. Shortening the annulopapillary distance after splitting the leaflet had no significant effect. CONCLUSIONS: Splitting the anterior mitral leaflet acutely impaired left ventricular contractility and haemodynamics in an ovine model. Shortening the annulopapillary distance after leaflet splitting did not further impair left ventricular function

Analogue Mean Systemic Filling Pressure: a New Volume Management Approach During Percutaneous Left Ventricular Assist Device Therapy

The absence of an accepted gold standard to estimate volume status is an obstacle for optimal management of left ventricular assist devices (LVADs). The applicability of the analogue mean systemic filling pressure (Pmsa) as a surrogate of the mean circulatory pressure to estimate volume status for patients with LVADs has not been investigated. Variability of flows generated by the Impella CP, a temporary LVAD, should have no physiological impact on fluid status. This translational interventional ovine study demonstrated that Pmsa did not change with variable circulatory flows induced by a continuous flow LVAD (the average dynamic increase in Pmsa of 0.20 ± 0.95 mmHg from zero to maximal Impella flow was not significant (p = 0.68)), confirming applicability of the human Pmsa equation for an ovine LVAD model. The study opens new directions for future translational and human investigations of fluid management using Pmsa for patients with temporary LVADs

On the Propagation of Slip Fronts at Frictional Interfaces

The dynamic initiation of sliding at planar interfaces between deformable and rigid solids is studied with particular focus on the speed of the slip front. Recent experimental results showed a close relation between this speed and the local ratio of shear to normal stress measured before slip occurs (static stress ratio). Using a two-dimensional finite element model, we demonstrate, however, that fronts propagating in different directions do not have the same dynamics under similar stress conditions. A lack of correlation is also observed between accelerating and decelerating slip fronts. These effects cannot be entirely associated with static local stresses but call for a dynamic description. Considering a dynamic stress ratio (measured in front of the slip tip) instead of a static one reduces the above-mentioned inconsistencies. However, the effects of the direction and acceleration are still present. To overcome this we propose an energetic criterion that uniquely associates, independently on the direction of propagation and its acceleration, the slip front velocity with the relative rise of the energy density at the slip tip.Comment: 15 pages, 6 figure

The scattering and extinction properties of nanodiamonds

The study of scattering and extinction properties of possible nanodiamond grains in the ISM are reported. Calculations using Discrete Dipole Approximation (DDA) for varying ellipsoidal shapes and sizes from 2.5 to $10 nm$ are considered. Nanodiamonds show negligible extinction from IR to near-UV and very sharp far-UV rise. Comparison with observations rule out possibility of independent nanodiamond dust but point towards possibility of nanodiamonds as a component in the ISM. Radiation induced transformations may lead to carbonaceous grains with different core and mantles. So calculations are also performed for a core-mantle target model with nanodiamond core in graphite mantles. The graphite extinction features get modified with the peak at 2175 \AA{} being lowered, broadened, blue shifted and accompanied by enhanced extinction in the far-UV. Such variations in the 2175 \AA{} band and simultaneous far-UV rise are observed along some sources. A three component dust model incorporating silicate, graphite and graphite with nanodiamond core is also considered. The model extinction compares very well with the average galactic extinction in the complete range from 0.2 to $10 \mu m^{-1}$. The best fit requires small size and small number of nanodiamonds.Comment: Accepted for publication in MNRAS; 8 Figure