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Efficient pumping of the healthy left ventricle (LV) requires heterogeneities in mechanical function of individual cardiomyocytes (CM). Deformation of sub-endocardial (Endo) tissue is greater than that of sub-epicardial (Epi) regions. Papillary muscles (PM), often considered to be part of Endo tissue, show lower beat-by-beat length variation than Epi (or Endo) regions, even though they contribute to the shift in atrio-ventricular valve plane, which is essential for LV pump function. Thus far, no comparative assessment of CM mechanics for PM and LV free wall has been published. Here, we investigate contractility and cytosolic calcium concentration ([Ca

An assemblage of species in a locality comprises two components, namely (i) species that are present (realised diversity) and (ii) species from the regional pool that may potentially inhabit this locality due to suitable ecological conditions, but that are absent (dark diversity). We investigated factors affecting the dark diversity of component communities of fleas parasitic on small mammals in the northern Palearctic at two scales. First, we considered the dark diversity of flea assemblages of the same host (for 13 host species) across regions and tested for the effects of environmental factors and the number of available host species on the dark diversity of within-region flea assemblages. Second, we considered the dark diversity of fleas across host species within a region (for 20 regions) and asked whether within-host dark diversity is associated with host phylogeny and/or traits. We found that the dark diversity of flea assemblages harboured by small mammals varied substantially (i) within the same host species across space (in 12 of 13 host species) and (ii) between host species within a region (in eight of 20 regions). The size of the dark diversity of flea assemblages of the same host across regions was generally affected by environmental factors (mainly by the amount of green vegetation), whereas the size of the dark diversity of flea assemblages of a host species within a region was affected by host traits (mainly by the degree of host sociality and the structure of its shelter and, to a lesser degree, by its geographic range size) but was not associated with host phylogenetic affinities. We conclude that application of the dark diversity concept to parasite communities across space or hosts allows a better understanding of the factors affecting the species richness and composition of these communities.

Infected abscesses are walled-off collections of pus and bacteria. They are a common sequela of complications in the setting of surgery, trauma, systemic infections, and other disease states. Current treatment is typically limited to antibiotics with long-term catheter drainage, or surgical wash-out when inaccessible to percutaneous drainage or unresponsive to initial care efforts. Antibiotic resistance is also a growing concern. Although bacteria can develop drug resistance, they remain susceptible to thermal and mechanical damage. In particular, short pulses of focused ultrasound (i.e., histotripsy) generate mechanical damage through localized cavitation, representing a potential new paradigm for treating abscesses non-invasively, without the need for long-term catheterization and antibiotics. In this pilot study, boiling and cavitation histotripsy treatments were applied to subcutaneous and intramuscular abscesses developed in a novel porcine model. Ultrasound imaging was used to evaluate abscess maturity, for treatment monitoring and assessment of post-treatment outcomes. Disinfection was quantified by counting bacteria colonies from samples aspirated before and after treatment. Histopathological evaluation of the abscesses was performed to identify changes resulting from histotripsy treatment and potential collateral damage. Cavitation histotripsy was more successful in reducing the bacterial load while having a smaller treatment volume compared with boiling histotripsy. The results of this pilot study suggest focused ultrasound may lead to a technology for in situ treatment of acoustically accessible abscesses.

Large intra-abdominal, retroperitoneal and intramuscular hematomas are common consequences of sharp and blunt trauma and post-surgical bleeds, and often threaten organ failure, compartment syndrome or spontaneous infection. Current therapy options include surgical evacuation and placement of indwelling drains that are not effective because of the viscosity of the organized hematoma. We have previously reported the feasibility of using boiling histotripsy (BH)—a pulsed high-intensity focused ultrasound method—for liquefaction of large volumes of freshly coagulated blood and subsequent fine-needle aspiration. The goal of this work was to evaluate the changes in stiffness of large coagulated blood volumes with aging and retraction in vitro, and to correlate these changes with the size of the BH void and, therefore, the susceptibility of the material to BH liquefaction. Large-volume (55–200 mL) whole-blood clots were fabricated in plastic molds from human and bovine blood, either by natural clotting or by recalcification of anticoagulated blood, with or without addition of thrombin. Retraction of the clots was achieved by incubation for 3 h, 3 d or 8 d. The shear modulus of the samples was measured with a custom-built indentometer and shear wave elasticity (SWE) imaging. Sizes of single liquefied lesions produced with a 1.5-MHz high-intensity focused ultrasound transducer within a 30-s standard BH exposure served as the metric for susceptibility of clot material to this treatment. Neither the shear moduli of naturally clotted human samples (0.52 ± 0.08 kPa), nor their degree of retraction (ratio of expelled fluid to original volume 50%–58%) depended on the length of incubation within 0–8 d, and were significantly lower than those of bovine samples (2.85 ± 0.17 kPa, retraction 5%–38%). In clots made from anticoagulated bovine blood, the variation of calcium chloride concentration within 5–40 mmol/L did not change the stiffness, whereas lower concentrations and the addition of thrombin resulted in significantly softer clots, similar to naturally clotted human samples. Within the achievable shear modulus range (0.4–1.6 kPa), the width of the BH-liquefied lesion was more affected by the changes in stiffness than the length of the lesion. In all cases, however, the lesions were larger compared with any soft tissue liquefied with the same BH parameters, indicating higher susceptibility of hematomas to BH damage. These results suggest that clotted bovine blood with added thrombin is an acceptable in vitro model of both acute and chronic human hematomas for assessing the efficiency of BH liquefaction strategies.

Well-preserved remains of a Posidonia oceanica meadow have been found in a Lower Pleistocene (Calabrian) succession cropping out near Fauglia (Tuscany, Italy). This paper analyses and describes the benthic foraminiferal community associated with this well-preserved Pleistocene P. oceanica meadow, with the purpose of testing the usefulness of foraminifera as an Indirect Palaeo-Seagrass Indicator (IPSI), providing both qualitative and quantitative parameters to recognize other meadow-related environments where fossil remains of seagrasses are not preserved. Despite being influenced by some diagenetic processes that might have affected the foraminiferal assemblage, the Fauglia succession represents a suitable setting for testing benthic foraminifera as IPSI in a temperate environment. Considering this limitation, together with other ecological constraints such as seawater temperature, this study provides evidence of the high potential of benthic foraminifera as IPSI. Several parameters such as the modified Foraminifera Index (FI’), the “long vs. short life-span index” (ILS), and the presence of permanently attached, encrusting foraminifera were tested. New indexes were also developed, namely the K/R ratio, consisting of the ratio between keeled Elphidium and the sum of rounded elphidiids (e.g., Elphidium translucens, Cribroelphidium, Porosononion) and Haynesina, and the K/REXT ratio, consisting of the ratio between keeled Elphidium and the sum of rounded elphidiids, Haynesina and other related genera that display a rounded periphery (i.e., Astrononion, Melonis, Nonion, Nonionella, Valvulineria). All these indexes were examined, suggesting their potential use for recognizing seagrass-related palaeoenvironments. The K/REXT ratio (and K/R) in association with the presence of permanently attached foraminifera revealed to be the most reliable palaeo-seagrass indicators, suggesting that this combination could be very useful also in other case studies where diagenesis altered the foraminiferal association.

During the second half of the Holocene, the Russian Plain experienced several climatic oscillations giving rise to changing vegetation patterns. The spatial variability of vegetation changes and its effects on soils is still a matter of debate. In the present study landscape response to Holocene climatic cycles was analysed on the base of detailed morphological, chemical and microbiomorphic analyses of a paleosol buried under the kurgan of the Abashevo culture (Middle Bronze Age) and a surface soil. Both soils located at the Tokhmeyevo kurgan cemetery (the Middle Volga region, Chuvash Republic, Russia) developed from the same parent material (mantle loam), at the same elevation and in close proximity to each other. Both soils, classified as Retisols, show a similar morphology and key analytical features indicating similar environment. The pollen and phytolith spectra confirm that both buried and surface soils formed under similar forest vegetation. The buried and surface soils at the Tokhmeyevo cemetery could be compared with the previously studied soils of the Sareevo settlement of the Early Iron Age and the Taushkasy kurgan cemetery of the Bronze Age. These studies confirm the stability of the forest environment at the southern boundary of the forest belt since the Bronze Age. At the same time, the buried soil at the Tokhmeyevo cemetery has a thick mollic horizon and black organic coatings overlaying brown clay cutans in the argic horizons, which sets it apart from the surface soil. The radiocarbon dates for the humus in the mollic horizon and black coatings in the argic horizon are surprisingly close to each other (about 5.5 cal ka BP and 5.2 cal ka BP, respectively). The data indicate that the black cutans are derived from degradation of the mollic horizon caused by a sudden increase in humidity during the episodes of extreme summer rainfall events. Our study also prove that the Abashevo people had complicated burial funeral rites. The earth mounds are made of the upper horizons of soils cut off from the surface in the vicinity. The central part of the mound consists of soil bricks with albic material used for the interior, while artificially rumpled material of the argic horizon was used for coverage. The use of albic and artificially rumpled material of argic horizon for earth mound construction implies the similarity between the buried and surface soils since the Bronze Age until today. Thus, the study of such construction techniques is important both for archaeology and paleogeography (paleopedology).

The southern steppes of European Russia are rich in archaeological monuments that were extensively studied for many decades. Nevertheless, paleosols buried under the burial mounds and especially the big kurgans of the Bronze Age in the Ponto-Caspian area did not receive proper attention. The paper focuses on soil evolution and climate dynamics during the Bronze Age based on the study of soils buried during several stages of earthen mound construction within one big kurgan in the Kuban-Azov Plain, Russia. The kurgan 1 in the Beysuzhek-9 kurgan cemetery of the Bronze Age, situated in the Korenovsky District, Krasnodar Region, consists of three earthen mounds made at different times. The soils, buried under three mounds of the kurgan, are located in close vicinity from each other and have similar lithology and geomorphic position. They form a chronosequence representing three time slices. Moreover, the chronosequence displays a certain chronological order of burial: paleosols were first buried in the center of the kurgan and later closer to its periphery. The height of the kurgan is about 4 m that ensures good preservation of the buried soils. The research is based on the comparative analysis of morphology, micromorphology and analytical properties of three paleosols buried under different constructions in the kurgan and surface soil. Also, the palynological analysis was performed for the uppermost layers (0–5 cm) of three paleosols. During the first stage of the kurgan construction, the Novotitorovo archaeological culture of the Early Bronze Age at the 27th-22nd centuries BC, the climate of the region was sufficiently humid and provided a high bioproductivity for surrounding landscapes. The interval between the second and third stages of kurgan construction was marked by the gradual increase in aridity. During the third stage of the kurgan construction (the Catacomb archaeological culture, the Middle Bronze Age, the 21st −16th centuries BC), the climate was mostly arid. The results of the palynological analysis are in agreement with the study of paleosols. During the construction of the kurgan, the vegetation pattern corresponded to a Southern forest-steppe. The percentage of herbaceous plants increased markedly, and steppe species appeared during the time of Catacomb culture.

Based on laws of theory of materials strengthening were discribed the experimentally obtained alloying effect in Mg-Ga system and shown using program for 3d atomic structures. As known from our experiments a homogeneous “wavy” microstructure of the diffusion zone forms as result of mass-transfer of molten gallium into the volume of magnesium alloys. SEM chemical composition shows Mg 65% wt. and Ga 35% wt. and X-ray spectra diffraction data - Mg5Ga2 intermetallic phase formation. Such intermetallic diffusion zone provides the significant strengthening effect of microstructure which was determined experimentally by the indentation method. The 3-d visualization shows the reaction and changing of an original crystal structure of magnesium atomic lattice upon diffusion doping with foreign atoms of gallium and then is shown the coalescence of Mg5Ga2 intermetallic crystal with crystals surfaces of Mg-matrix. So, investigated Mg-alloy strengthening at alloying with Ga explained by two main factors. At first is the formation of intermetallic phases with the ordering and consolidation of the crystal structure of the matrix by the ligature atoms, which is the key factor of the strengthening mechanism fixed experimentally. Second, when hexagonal and orthorhombic atomic structures growth according to their spatial type, a significant disorientation of structural fragments occurs, an increase in the density of the amorphous transition layer, a twinning of the structure in the interphase boundaries, which leads to the formation of intrinsic mutual deformation and a high level of internal stresses.

Parasites can cause a broad range of sublethal fitness effects across a wide variety of host taxa. However, a host's efforts to compensate for possible parasite-induced fitness effects are less well-known. Parental effects may beneficially alter the offspring phenotype if parental environments sufficiently predict the offspring environment. Parasitism is a common stressor across generations; therefore, parental infestation could reliably predict the likelihood of infestation for offspring. However, little is known about relationships between parasitism and transgenerational phenotypic plasticity. Thus, we investigated how maternal and grandmaternal infestation with fleas (Xenopsylla ramesis) affected offspring quality and quantity in a desert rodent (Meriones crassus). We used a fully-crossed design with control and infested treatments to examine litter size, pup body mass at birth, and pup mass gain before weaning for combinations of maternal and grandmaternal infestation status. No effect of treatment on litter size or pup body mass at birth was found. However, maternal and grandmaternal infestation status significantly affected pre-weaning body mass gain, a proxy for the rate of maturation, in male pups. Pups gained significantly more weight before weaning if maternal and grandmaternal infestation statuses matched, regardless of the treatment. Thus, pups whose mothers and grandmothers experienced similar risks of parasitism, either both non-parasitized or both infested, would reach sexual maturity more quickly than those pups whose mothers' infestation status did not match that of their grandmothers. These results support the contention that parents can receive external cues such as the risk of parasitism, that prompt them to alter offspring provisioning. Therefore, parasites could be a mediator of environmentally-induced maternal effects and could affect host reproductive fitness across multiple generations.

A catena of the Holocene soils and interstadial Bryansk paleosol has been studied within a small closed depression in the Kazatskaya Steppe site on the Central Russian Upland. This depression is located on the territory of the Central Chernozem Biospheric Reserve, Kursk region and presumably originated from suffosion processes. Our research is aimed at understanding of interrelations between the macro- and micromorphological characteristics, certain physical and chemical properties of the Bryansk paleosols, on one hand, and those of the superimposed Holocene soil on another, taking into consideration various conditions of the present-day microrelief. The studied catena is a typical component of the landscape and soil cover structure for watersheds of the Central Russian Upland. On the micro-elevation rising 80 cm above the micro-depression bottom, the Typical Chernozems (Haplic Chernozems) are developed, on the slope – the Leached Chernozems (Luvic Chernozems), and at the bottom – the Meadow Chernozems (Stagnic Chernozems). The upper humus horizons of the Holocene soil present in all sectors of the catena. The thickness of the Ah horizon increases slightly, whereas the AB horizon decreases toward the bottom of the depression. On the slopes and at the bottom of the depression, the Ah2 sub-horizon is replaced with the AE horizon, and the Bk horizon becomes carbonates-free and turns into the Bt horizon. The change of the “normal” profile of paleosol of warm interstadial in final phase of MIS 3 started already in the last stages of its formation. The Bryansk soil is heavily deformed by cryogenic processes during the Valdai glaciation maximum (the Vladimir cryogenic horizon, MIS 2). The secondary diagenesis of the Bryansk paleosol is related to the Holocene soil-forming processes. The Holocene soils are superimposed on the Middle Valdai Bryansk paleosol, transforming it in different ways in different sectors of catena. On micro-elevation the Holocene diagenesis is minimal and consists in fragmentation by mesofauna, additional penetration of carbonates in the upper horizon of the paleosol. At the bottom of the micro-depression the Bryansk paleosol is the most transformed, and the entire profile of the Bryansk soil turned into illuvial horizon of the Holocene meadow-chernozem soil.