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101.
Witold Cieślikiewicz Aleksandra Dudkowska Gabriela Gic-Grusza Jan Jędrasik 《Journal of Soils and Sediments》2018,18(12):3437-3447
Purpose
Environment-friendly management of sites used for disposal of locally generated sedimentary material involves designation of an optimal dumping site location which will render the dredged material re-usable for beneficial purposes. The objective of this research was to determine whether wind, waves, and currents can induce transport of sediment from offshore dumping sites located at intermediate depths in the southern Baltic.Materials and methods
The problem was addressed by exploring potential sediment transport from two sites located in the Gulf of Gdańsk at depths of about 20 m. A total of 29 combinations of hydrodynamic variables, representing the most extreme possible situations in the area, including eight theoretical uniform wind fields over the entire Baltic Sea from the W, NW, N, NE, E, SE, S, and SW sectors, the wind speed of 30 m s?1, as well as 21 historical extreme storms, retrieved from the HIPOCAS project database, were used.Results and discussion
The bottom velocities resulting from waves and currents at the dumping sites considered were computed using wave models (WAM, SWAN) and the M3D hydrodynamic model (based on the POM model). To estimate the velocities critical for bedload transport, formulae developed by Soulsby (1997) and Sawamoto and Yamashita (Proc Coastal Sediments 87:415–423, 1987) were used. The volumetric bedload transport was computed based on Meyer-Peter and Müller (1948). The model simulations demonstrated that, for the storm conditions analyzed, the current velocity in the area of the two dumping sites would be so low that it would practically not affect the magnitude of the bottom sediment transport. Thus, the resultant volume of bedload transported would be equal to that generated by the wave action. For the heaviest historical storm, the maximum transport is about 3?×?10?5 m2 s?1.Conclusions
Under conditions of theoretical storms, the bottom orbital velocities would be higher and the resultant sediment transport would reach almost 7?×?10?5 m2 s?1 for northerly winds. However, this value is still very low compared with the volume of sediment being dumped. The findings of this study may prove useful in designation of future dumping sites.102.
Aleksandra A. PANYUTINA Alexander N. KUZNETSOV Ilya A. VOLODIN Alexei V. ABRAMOV Irina B. SOLDATOVA 《Integrative zoology》2017,12(2):172-184
The means of orientation is studied in the Vietnamese pygmy dormouse Typhlomys chapensis, a poorly known enigmatic semi‐fossorial semi‐arboreal rodent. Data on eye structure are presented, which prove that Typhlomys (translated as “the blind mouse”) is incapable of object vision: the retina is folded and retains no more than 2500 ganglion cells in the focal plane, and the optic nerve is subject to gliosis. Hence, Typhlomys has no other means for rapid long‐range orientation among tree branches other than echolocation. Ultrasonic vocalization recordings at the frequency range of 50–100 kHz support this hypothesis. The vocalizations are represented by bouts of up to 7 more or less evenly‐spaced and uniform frequency‐modulated sweep‐like pulses in rapid succession. Structurally, these sweeps are similar to frequency‐modulated ultrasonic echolocation calls of some bat species, but they are too faint to be revealed with a common bat detector. When recording video simultaneously with the ultrasonic audio, a significantly greater pulse rate during locomotion compared to that of resting animals has been demonstrated. Our findings of locomotion‐associated ultrasonic vocalization in a fast‐climbing but weakly‐sighted small mammal ecotype add support to the “echolocation‐first theory” of pre‐flight origin of echolocation in bats. 相似文献
103.
Marta Walczak Tadeusz Jezierski Aleksandra Górecka-Bruzda Magdalena Sobczyńska John Ensminger 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(5):283-294
The aim of this study was to assess the progress in operant conditioning of dogs during 3 training phases up to a level where the dogs performed a minimum of 40 correct indications without false alerts and hesitations in at least 100 trials in each phase, and to compare the training results with the working phase. Breath samples from 57, 45, and 118 patients with breast cancer, melanoma, and lung cancer, respectively, were used as patterns, with samples from 305 healthy volunteers as controls. Six dogs in 2 age-groups (20 months vs. 6 months old) were used for the training. In phase I, the dogs were trained to indicate by sitting or lying down before the breath samples taken from cancer patients (pattern odor) coupled with food odor and placed among 4 blank samples (a lineup of 5 samples). In phase II, a pattern sample without food odor was placed among blank samples. In phase III as well as in the working phase, a pattern sample was placed among control samples. Significant individual differences were found in dogs’ performance during the training. The percentage of trials with prompts to achieve self-dependent work decreased in older dogs in consecutive training phases, but increased in phase II in the younger dogs. The increasing level of challenge in consecutive training phases resulted in a higher percentage of false alerts and misses, and in younger dogs, decreased motivation for sniffing the odor samples was observed in training phase III. Nonsignificant and negative correlations between the training phases and working phase in the percentage of correct indications and false alerts show that it is difficult to predict the performance of fully trained dogs on the basis of the results achieved during the training. Fully trained dogs discriminated pattern breath samples (cancer) from healthy controls with 79% sensitivity and 78% specificity, or with 50% sensitivity at the probability of correct response by chance of 50% and 20%, respectively. The sensitivity decreased to 68% and 37%, respectively, when each sample was tested only once, although being better than by chance (P < 0.05). The percentage of false alerts and misses is difficult to reduce during the training; thus, the percentage of correct indications tended to decrease in the course of training phases II and III. Odor samples taken in hospitals may contain components of “hospital odors,” which may be a confounding factor for dogs’ indications. Using trained dogs for cancer screening on the basis of detection of odor markers still requires further study. 相似文献
104.
Quantifying the spatial relationship between bird species’ distributions and landscape feature boundaries in southern Ontario, Canada 总被引:2,自引:1,他引:1
Aleksandra E. Polakowska Marie-Josée Fortin Andrew Couturier 《Landscape Ecology》2012,27(10):1481-1493
Understanding what features of the landscape affect species distribution is critical to effectively implement conservation strategies. This study investigates how a boundary analysis framework can be used to characterize the spatial association between boundaries (i.e., spatial locations of high rates of change) in bird species?? distributions and landscape features at the regional scale. The study area covers 92,000?km2 in southern Ontario (Canada) and extends from the Great Lakes-St. Lawrence biome to the southern Canadian Shield biome. Landcover composition was derived from Ontario Land Cover data (1991?C1998; 7 types) and elevation data were derived from the Canada3D digital elevation model. Bird distributions were estimated using indicator kriging based on point counts obtained from the Ontario Breeding Bird Atlas data (2001?C2005; 60 species). Boundaries were delineated for both data types using a 10?×?10?km cell resolution. Spatial boundary overlap statistics were used to quantify the spatial relationship between landscape features and bird boundaries and tested using a randomization procedure. There was significant positive association and spatial overlap between delineated landscape feature boundaries and bird boundaries. The number of spatially overlapping cells between the two boundary types was 67 out of 164 (41?%) and 76?% of cells were within 11.42?km of each other. These results were statistically significant (P?<?0.001) and suggest a strong spatial relationship between high rates of change in landscape features and bird species?? distributions at the regional scale. A boundary analysis framework could be used to identify boundary shifts in response to climate change and anticipate changes in species distributions. 相似文献
105.
Andreyeva Aleksandra Yu. Kladchenko Ekaterina S. Sudnitsyna Julia S. Krivchenko Aleksander I. Mindukshev Igor V. Gambaryan Stepan 《Fish physiology and biochemistry》2021,47(4):1105-1117
Fish Physiology and Biochemistry - Activation of the cAMP pathway by β-adrenergic stimulation and cGMP pathway by activation of guanylate cyclase substantially affects red blood cell (RBC)... 相似文献
106.
107.
Pintar T Pleskovic A Alessiani M Abbiati F Milutinović A Petrovic D Pogacnik M Zorc-Pleskovic R 《Acta veterinaria Hungarica》2007,55(4):533-541
Intestinal transplantation is being increasingly performed to treat patients with irreversible intestinal failure. The major cause of intestinal graft failure is graft-versus-host disease (GVHD) that represents a life-threatening complication after small bowel transplantation (Itx). The purpose of this study was to assess the diagnostic and prognostic value of skin biopsy histological changes for acute GVHD after Itx in pigs. Thirty-four Large White pigs were divided into three groups: Group 1 with Itx only, Group 2 with Itx and donor bone marrow infusion (Itx BM) and Group 3 (control group - before the operation). Animals received tacrolimus-based immunosuppression from day 0 to day 30 postoperatively. Skin and small bowel biopsies were histologically assessed, analysed and classified from grade 1 to 4 on postoperative days 15, 30, 45 and 60. There was a strong correlation between the histological grading values of skin biopsy changes and the histological grading values of small bowel biopsy changes (Kendall's tau_b is 0.855 for the Itx group and 0.730 for the Itx BM group). The significant correlation found between skin and small bowel histological changes suggests the prognostic value of skin biopsies after Itx. In conclusion, our findings emphasise the diagnostic and prognostic value of skin biopsy analysis for acute GVHD after Itx. 相似文献
108.
Zarzyńska-Nowak Aleksandra Jeżewska Małgorzata Hasiów-Jaroszewska Beata Zielińska Lidia 《植物病害和植物保护杂志》2015,122(4):153-160
Journal of Plant Diseases and Protection - Electron microscopy studies were carried out to investigate the association of visible disease symptoms with ultrastructural changes in barley plants... 相似文献
109.
Piotr Kupczyk Marta Rykala Pawel Serek Aleksandra Pawlak Bartosz Slowikowski Marcin Holysz Grzegorz Chodaczek Jan P. Madej Piotr Ziolkowski Artur Niedzwiedz 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(4):1508
BackgroundThe endocannabinoid system (ECS) is composed of cannabinoid receptors type 1 (CBR1) and type 2 (CBR2), cannabinoid‐based ligands (endogenous chemically synthesized phytocannabinoids), and endogenous enzymes controlling their concentrations. Cannabinoid receptors (CBRs) have been identified in invertebrates and in almost all vertebrate species in the central and peripheral nervous system as well as in immune cells, where they control neuroimmune homeostasis. In humans, rodents, dogs, and cats, CBRs expression has been confirmed in the skin, and their expression and tissue distribution become disordered in pathological conditions. Cannabinoid receptors may be a possible therapeutic target in skin diseases.ObjectivesTo characterize the distribution and cellular expression of CBRs in the skin of horses under normal conditions.AnimalsFifteen healthy horses.MethodsUsing full‐thickness skin punch biopsy samples, skin‐derived primary epidermal keratinocytes and dermal‐derived cells, we performed analysis of Cnr1 and Cnr2 genes using real‐time PCR and CBR1 and CBR2 protein expression by confocal microscopy and Western blotting.ResultsNormal equine skin, including equine epidermal keratinocytes and dermal fibroblast‐like cells, all exhibited constant gene and protein expression of CBRs.Conclusions and Clinical ImportanceOur results represent a starting point for developing and translating new veterinary medicine‐based pharmacotherapies using ECS as a possible target. 相似文献
110.
Aleksandra Ukalska-Jaruga Guillaume Debaene Bożena Smreczak 《Journal of Soils and Sediments》2018,18(8):2833-2843