Physiological responses of orchids to prolonged clinorotation

Creation of plant-based bioregenerative life support systems is crucial for future long-duration space exploring missions. Microgravity is one of the major stresses affecting plant growth and development under space flight conditions. Search for higher plant genotypes resilient to microgravity as well as revealing of biological features which could be used as markers of such resilience is rather urgently needed. The objective of this study was to analyze physiological and biochemical responses of three orchid species representing different life forms (terrestrial and epiphytic), growth types (monopodial and sympodial) and pathways of CO2 fixation to long-term (24 months) clinorotation which modeled the combined effect of two stress factors: hermetic conditions and microgravity. Three years old meristematic orchids Cypripedium flavum, Angraecum eburneum, Epidendrum radicans, representing different life forms, types of branching shoot system and pathways of CO2 fixation, were used as test-plants. The microgravity was simulated using three-dimensional (3-D) clinostat equipped with two rotation axes placed at right angles (rotation frequency was 3 rpm) in controlled conditions of air temperature, illumination, air humidity and substrate moisture. The control plants were grown in the similar plastic vessels but not hermetically sealed and without clinorotating in the same environmental conditions. The vital state of the test plants was assessed using characteristics of mineral nutrition, content of photosynthetic pigments, free amino acids, soluble proteins, DNA and RNA, enzymatic and non-enzymatic antioxidants. The results of this study confirmed that orchids grown under simulated microgravity and kept in hermetically-sealed vessels were subjected to oxidative stress, which could be responsible for the observed inhibition of basic physiological processes such as mineral nutrition, metabolism of aminoacids, protein biosynthesis and photosynthesis. Monopodial orchids C. flavum and A. eburneum demonstrated better adaptation to prolonged clinorotation as compared to sympodial E. radicans. In particular, the latter demonstrated some stimulation of mineral nutrition processes (i.e. K, N, Fe, Mn, Zn accumulation), content of photosynthetic pigments, proline and superoxide dismutase activity. Long-lasting clinorotation induced adaptive changes of antioxidant systems in the studied orchids (e.i. increase in carotenoids and proline content and stimulation of superoxide dismutase activity), which helped to maintain the main physiological functions at stable level in the above-mentioned stressful conditions. The following biochemical characteristics in the studied orchids could be considered as markers of resilience to simulated microgravity and hermetic conditions: 1) an increase in the accumulation of non-enzymatic (proline, carotenoids) and enzymatic antioxidants (superoxide dismutase); 2) ability to maintain stable balance of mineral nutrients; 3) increase in the content of photosynthetic pigments; 4) increase in the content of proteinogenic amino acids and soluble proteins; 5) increase in the DNA content or RNA/DNA ratio. Our studies have also demonstrated a correlation between orchid ecomorphological characteristics such as type of branching with their adaptive responses to prolonged clinorotation. We observed no correlation between the studied life form of orchids, ecotype or the pathway of CO2 fixation and their resilience to prolonged clinorotation. This research can be a starting point for studying the relationships between ecomorphological features of various orchids and their resilience to microgravity conditions in the search for biological markers of microgravity tolerance in species of higher plants

Endonasal orbitotomy as a first treatment for posttraumatic intraorbital hemorrhages in patients with frontal basilar trauma

Background: Intraorbital hemorrhages are one of the most dangerous complications of frontal bone trauma and frontal and orbital trauma because of the close and intricate anatomical relationships among the cranial cavity, orbit, nose and paranasal sinuses. Failure to solve the problem promptly will inevitably lead to disability. Effective treatment requires a multidisciplinary surgical team including a neurosurgeon, otorhinolaryngologist, ophthalmologist and a maxillofacial surgeon. Purpose: To assess the efficacy of endonasal endoscopic transethmoidal orbitotomy (TEO) and transcutaneous orbitotomy (TCO) in patients with post-traumatic intraorbital hemorrhages. Material and Methods: Fifteen patients (9 men and 6 women) with retrobulbar hematoma were included in this study. Patient age ranged from 33 years to 65 years. Of the 15 patients, 8 received endonasal endoscopic TEO and 7, TCO. Preoperatively, each patient underwent an eye examination, ultrasonography of the orbit, and spiral computed tomography of the paranasal and periorbital sinuses. Postoperative examinations were performed at 7 days and 1 month. Exophthalmos was assessed using a Hertel’s exophthalmosmeter (ALMAS YZ9). Sivtsev-Golovin charts were used to assess visual acuity. Statistical analyses were conducted using Microsoft Excel and Statistica (StatSoft, Tulsa, OK, USA) software. Results: The preoperative exophthalmos was 18.5 ± 2.12 mm in patients scheduled for TEO and 16.9 ± 1.78 mm in those scheduled for TCO. On day 7 after surgery (the day of discharge), exophthalmos reduced to 6.4 ± 0.77 mm in patients undergoing TEO (p < 0.0005) and 8.8 ± 0.94 mm in those undergoing TCO (p < 0.005). The preoperative visual acuity (VA) was 0.07 ± 0.03 in patients scheduled for TEO and 0.09 ± 0.05 mm in those scheduled for TCO. On day 7, mean VA improved to 0.81 ± 0.12 (p < 0.00005) in patients undergoing TEO, and to 0.56 ± 0.34 in those undergoing TCO. The two groups showed practically the same pattern of a longitudinal decrease in chemosis. Diplopia in upward and downward gaze and any restriction in ocular motility disappeared in patients undergoing TEO by the day of discharge (day 7), which was 4-5 days earlier than in patients undergoing TCO, with a postoperative period 4.25 ± 0.75 days longer (p<0.05) in the latter patients. At one month, mean VA improved to 0.89 ± 0.08 (p < 0.00005) in patients of the TEO group, and to 0.75 ± 0.15 (p < 0.005) in patients of the TCO group. Conclusion: Endonasal endoscopic transethmoidal orbitotomy was significantly more advantageous than transcutaneous orbitotomy, with a faster recovery, particularly, shorter postoperative period, faster restoration of visual acuity and ocular motility, minimum trauma to soft orbital tissues, and no external damage to facial skin

Dataset and metrics for predicting local visible differences

A large number of imaging and computer graphics applications require localized information on the visibility of image distortions. Existing image quality metrics are not suitable for this task as they provide a single quality value per image. Existing visibility metrics produce visual difference maps, and are specifically designed for detecting just noticeable distortions but their predictions are often inaccurate. In this work, we argue that the key reason for this problem is the lack of large image collections with a good coverage of possible distortions that occur in different applications. To address the problem, we collect an extensive dataset of reference and distorted image pairs together with user markings indicating whether distortions are visible or not. We propose a statistical model that is designed for the meaningful interpretation of such data, which is affected by visual search and imprecision of manual marking. We use our dataset for training existing metrics and we demonstrate that their performance significantly improves. We show that our dataset with the proposed statistical model can be used to train a new CNN-based metric, which outperforms the existing solutions. We demonstrate the utility of such a metric in visually lossless JPEG compression, super-resolution and watermarking.</jats:p

Depth concentrations of deuterium ions implanted into some pure metals and alloys

Pure metals (Cu, Ti, Zr, V, Pd) and diluted Pd-alloys (Pd-Ag, Pd-Pt, Pd-Ru, Pd-Rh) were implanted by 25 keV deuterium ions at fluences in the range (1.2{\div}2.3)x1022 D+/m2. The post-treatment depth distributions of deuterium ions were measured 10 days and three months after the implantation using Elastic Recoil Detection Analysis (ERDA) and Rutherford Backscattering (RBS). Comparison of the obtained results allowed to make conclusions about relative stability of deuterium and hydrogen gases in pure metals and diluted Pd alloys. Very high diffusion rates of implanted deuterium ions from V and Pd pure metals and Pd alloys were observed. Small-angle X-ray scattering revealed formation of nanosized defects in implanted corundum and titanium.Comment: 12 pages, 9 figure

Geochemical evidence for gas hydrate in sediment near the Chile Triple Juction

Coring at ODP Sites 859, 860, and 861 near the Chile Triple Junction failed to recover anticipated gas hydrate that was inferred to be present from two lines of geophysical evidence: pre-cruise observation of a weak to strong bottom simulating reflector (BSR) marking the predicted base of the gas-hydrate stability zone, and post-cruise interpretation of the velocity and resistivity logs at Site 859 that suggests the presence of gas hydrate. In contrast to other gas-hydrate occurrences observed during previous DSDP and ODP drilling, this Chile Margin sediment is very low in contents of total organic carbon (TOC < 0.5%) and residual methane (C₁), that are inconsistent with an in-situ source of methane for gas-hydrate formation. However, methane/ethane (C₁/C₂) ratios (>200) and δ¹³ C, values (<-60‰) show little evidence that the methane came from deeper thermogenic sources. Pore-fluid freshening does, however, suggest that gas hydrate is present, disseminated thinly and heterogeneously throughout the stability zone, and occupies less than 25% of the available pore space. The environment of the gas hydrate in sediment near the Chile Triple Junction has unique characteristics relative to known gas-hydrate occurrences elsewhere

A summary of ODP leg 141 hydrogeologic, geochemical and thermal results

The subduction of the oceanic spreading center at the Chile Triple Junction is marked by a substantial thermal perturbation and marked changes in the hydrogeologic and aqueous geochemical regimes in the overthrust plate. Ridge subduction substantially changes the fluid chemistry in the wedge through variably hydrating the oceanic basement, accretionary wedge, and continental backstop. This generates positive anomalies in salinity and chloride values with respect to sea water. The wedge immediately above the subducted ridge also experiences greatly enhance diagenesis and cementation together with the influx of primordial mantle derived ⁴He. Linear temperature and pore fluid chemistry profiles suggest a predominantly diffusive/conductive regime predominates in the interior eastern portion of the wedge and continental backstop region. In contrast, a vigorous and transient hydrogeolgic system within 5 km of the toe of the wedge at both Sites 859 and 863 generates spatially narrow, large, and complex anomalies in temperature and fluid chemistry. At the toe the vigorous hydrogeologic system may be variably influenced by the episodic expulsion of fluid from both the deeper parts of the wedge and oceanic basement driven convection systems. Structural and diagenetic observations are also consistent with a hydrogeologic regime that both evolves with time and that is dominated by episodic processes. In particular, studies of cements, mineralized veins, deformation bands, and Fe sulfide distribution suggest that above the subducting ridge (i.e., Site 863) the lithification in the wedge is greatly enhanced and that and periods of enhanced fluid expulsion are associated with local hydrofracture and dilation episodes

Investigation of Thermal Processes in Two-Layer Materials Exposed to High-Energy Heavy Ions in the Framework of a Thermal Peak Model with Constant Thermal Parameters

A system of equations for temperatures of electronic gas and lattice around and along a trajectory of a 710-MeV heavy ion of bismuth $^{209}$Bi in a two-layer material Ni(2 $\mu$m)/W at constant thermal parameters is solved numerically in an axial-symmetric cylindrical system of coordinates. On the basis of the obtained dependences of lattice temperature on radius around the ion trajectory and depth, one can make a conclusion that the ionization energy losses of bismuth ion in the target material are sufficient for melting. The sizes of regions with maximum radius and depth in the target material, where the phase transformations can take place, are estimated