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The analyses of 184 sediment targets and more than 70,000 individual grains revealed that along the Opportunity rover traverse there are four distinct fractions of deposits related to different geomorphological settings: (a) dust mixed with very fine sand is common behind topographical obstacles, (b) fine sands are deposited in depressions, (c) very coarse sands occur in coarse‐grained ripple fields, and (d) gravel dominates at the rims of craters and on bedrock as lag deposits. Medium size sands were not observed on the plains, but they can be trapped in relatively large craters, where they form dunes and are within coarse‐grained ripples and transverse aeolian ridges (TARs). The fine sands show no regional variations in chemical composition and granulometry, as these sands are easily transported by wind. The very coarse sands vary in composition and shape between the plains and the Endeavour crater rim as their sources are local and their transport distances are short. On the plains, the gravel and the coarse sands are enriched in iron and characterized by higher roundness than the grains from the Endeavour crater rim. The source of iron‐rich, rounded grains on the plains are hematite spherules that are eroded out of Burns formation rocks. The smallest, the best sorted, and the least rounded coarse sand samples are found on coarse‐grained ripple crests. They are mainly composed of spherule fragments and their low roundness indicates shorter transport path lengths than those of grains transported in the past when coarse‐grained ripples migrated. Plain Language Summary: The analyses of more than 70,000 individual grains revealed that there are four distinct types of sediments on Meridiani Planum: (a) dust mixed with very fine sand grains (diameter below 0.10 mm) are common behind topographical obstacles, (b) fine sand grains (diameters 0.10–0.25 mm) are deposited in depressions, (c) very coarse sand grains (diameters 1–2 mm) occur in coarse‐grained ripple fields, and (d) gravel (diameters above 2 mm) dominates at the rims of craters and on bedrock. Deposits composed of medium sand grains (diameter 0.25–0.50 mm) were not observed on the surface of the plains, but they can be trapped in relatively large craters, where they form dunes and are within coarse‐grained ripples and transverse aeolian ridges formed by wind. The fine sands show no regional variations, indicating that these sands are mixed on a regional scale by sand‐driving winds. The very coarse sands vary between the plains and the Endeavour crater rim, as their sources are local, and they can be moved by wind only over short distances. Key Points: Sediments on the plains are different from those at the Endeavour crater rim in terms of the shape and chemical composition of grainsMedium size sands are not present on the plains but are trapped in craters, where they can form dunesVery coarse sand grains are currently transported by wind but have shorter transport path lengths than grains transported in the past [ABSTRACT FROM AUTHOR]

Recent studies demonstrated that selected hormones/adipokines may be involved into the regulation of bone metabolism and bone marrow-derived hematopoietic stem/progenitor cells (HSPCs) mobilization in humans. Interestingly, in obese individuals significantly higher numbers of spontaneously circulating stem cells are also observed. Therefore in this study we comprehensively examined plasma and AT (subcutaneous and visceral/omental) levels of hormones/adipokines involved in HSPCs mobilization in lean, overweight and obese individuals as well as verified their potential associations with concentrations of HSPCs chemoattractant, stromal-derived factor-1 (SDF-1). Blood and AT samples (35 subcutaneous and 35 omental) were obtained from individuals undergoing elective surgery. Plasma and AT-derived interstitial fluid levels of resistin, visfatin, osteocalcin and SDF-1 were measured using ELISA. In our study obese patients had almost significantly (P<0.06) higher plasma visfatin and resistin levels as well as lower osteocalcin concentrations (P<0.04) than lean individuals. Osteocalcin and resistin concentrations were strongly associated with levels of SDF-1 and metalloproteinases (MMP 2 and 9). AT levels of all examined substances were significantly lower than the corresponding levels in the plasma (in all cases at least P<0.05), and depot-specific differences in the concentrations of these factors were found only in terms of osteocalcin and SDF-1. In addition, subcutaneous and visceral/omental concentrations of osteocalcin and visfatin, but not of resistin, were associated with values of such parameters as age, body mass or adiposity indexes (BMI and BAI, respectively) and/or waist-to-hip ratio (WHR). In summary, our study showed that in obese individuals the biochemical constellation of adipokines/hormones involved in the process of HSPCs mobilization resembles this observed during pharmacological HSPCs mobilization. Moreover, our study offers further indirect translational evidence for existence of a biochemical cross-talk between bone and AT metabolism (so called - bone-fat- axis) in humans.

Sphingosine-1-phosphate (S1P), which is a bioactive lipid from the family of sphingolipids is synthesized i.e. by platelates and stored in erythrocytes. The effects of this compound on the cells are connected with the presence of specific receptors on their surface (S1P1-S1P5). S1P acts upon, i.e, hematopoetic and nervous cells, having influencing their migration, adhesion, differentation and survival. This molecule plays mediator role in inflammatory responses, angiogenesis and wound healing. In contrast to spingosine and ceramid, S1P counteracts apoptosis. Recent studies have shown that S1P is a factor, which participates in the process of release stem cells from bone marrow to peripherial blood. Cell and tissue damaged, stress, physical exercise and some drugs have influence on the numbers of stem cells. The research on S1P as the main chemotactic factor for stem cells may have substantial impact on the development of regenerative medicine.

Objective: Recent advancements in thoracic endovascular aortic repair, such as branched endografts or hybrid debranching/thoracic endovascular aortic repair, have extended the option of endoluminal therapy into the realm of the aortic arch. A contemporary assessment of open arch repair to provide long-term data for comparative analysis for these newer therapies is timely, warranted, and presented in this article., Methods: Since the inception of our thoracic endovascular aortic repair program in 1993, 721 patients (mean age of 59.3 years, 68.9% were male) have undergone median sternotomy and open arch reconstruction with hypothermic circulatory arrest. Extended arch repair was performed in 42.7% with construction of bypasses to the innominate (296 patients), left carotid (216 patients), and subclavian (75 patients) arteries or elephant trunk procedures (42 patients). Concomitant aortic valve or aortic root replacement was required in 403 patients, and root reconstruction was required in 222 patients. Retrograde (641 patients) or antegrade (400 patients) cerebral perfusion was used for neuroprotection during hypothermic circulatory arrest. The operative procedure was urgent or emergency in 316 patients (43.8%) and included repair of type A dissection in 284 patients (39.3%). A total of 111 patients (15.4%) had undergone prior cardiac surgery. Primary outcomes in this study were early and late mortality. Follow-up was 100% complete (mean, 52.6 months)., Results: Thirty-day morbidity included death (36 patients [5%]), stroke (34 patients [4.7%]), and permanent dialysis (14 patients [1.9%]). Independent predictors of early mortality included advancing age, prolonged bypass times, and impaired ejection fraction (all P < .05). Actuarial survival at 10 years was 65%. Independent predictors of late mortality included advancing age, prolonged lower body circulatory arrest times, and increasing creatinine (all P < .05). By Kaplan-Meier analysis, 10-year survival was significantly reduced after operative procedures for type A dissection (non-type A 69.1% vs type A 58%, P = .003). Freedom from aortic reoperation (any segment) was 72.6% at 10 years., Conclusions: Open aortic arch repair can be accomplished with excellent early and late results. These outcomes provide objective data for comparison and suggest that newer endovascular therapies should be evaluated first in high-risk groups, such as those with advanced age or impaired renal function before broader application in all patients., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)