51 research outputs found

    Hyperspectral Imaging for Burn Depth Assessment in an Animal Model

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    Differentiating between superficial and deep-dermal (DD) burns remains challenging. Superficial-dermal burns heal with conservative treatment; DD burns often require excision and skin grafting. Decision of surgical treatment is often delayed until burn depth is definitively identified. This study\u27s aim is to assess the ability of hyperspectral imaging (HSI) to differentiate burn depth. METHODS: Thermal injury of graded severity was generated on the dorsum of hairless mice with a heated brass rod. Perfusion and oxygenation parameters of injured skin were measured with HSI, a noninvasive method of diffuse reflectance spectroscopy, at 2 minutes, 1, 24, 48 and 72 hours after wounding. Burn depth was measured histologically in 12 mice from each burn group (n = 72) at 72 hours. RESULTS: Three levels of burn depth were verified histologically: intermediate-dermal (ID), DD, and full-thickness. At 24 hours post injury, total hemoglobin (tHb) increased by 67% and 16% in ID and DD burns, respectively. In contrast, tHb decreased to 36% of its original levels in full-thickness burns. Differences in deoxygenated and tHb among all groups were significant (P \u3c 0.001) at 24 hours post injury. CONCLUSIONS: HSI was able to differentiate among 3 discrete levels of burn injury. This is likely because of its correlation with skin perfusion: superficial burn injury causes an inflammatory response and increased perfusion to the burn site, whereas deeper burns destroy the dermal microvasculature and a decrease in perfusion follows. This study supports further investigation of HSI in early burn depth assessment

    Perfusion Changes by Hyperspectral Imaging in a Burn Model

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    BACKGROUND: Early excision and skin grafting of full-thickness and deep-dermal burns is therapeutically advantageous. However, while full-thickness burns are clinically evident, differentiating between superficial versus deep partial-thickness burns presents a diagnostic challenge, with only 50-75% accuracy. Superficial-dermal burns heal, while deep-dermal burns often require excision and skin grafting. Decision of surgical treatment is often delayed until burn depth is definitively identified. This study’s aim is to establish a thermal burn model in mice in order to assess the ability of Hyperspectral Imaging (HSI) in differentiating burn depth. METHODS: Burns of graded severity were generated on the dorsum of seventy-six hairless mice with a brass rod heated to 50, 60, 70, 80, or 90°C. Perfusion and oxygenation parameters of the injured skin were measured with HSI, a non-invasive method of wide-field, diffuse reflectance spectroscopy at 2 minutes, 1 hour, 24 hours, 48 hours, and 72 hours after wounding. Burn depth was measured histologically (n=44) at 72 hours post injury using Masson’s trichrome staining. RESULTS: Three discrete levels of burn depth were verified histologically, as follows in order of increasing depth: intermediate-dermal, deep-dermal, and full-thickness injury. At 24 hours post injury, total hemoglobin increased by 67% and 18% in intermediate and deep dermal burns, respectively. In contrast, total hemoglobin decreased by 64% in full-thickness burns. Differences in deoxygenated hemoglobin, total hemoglobin, and oxygen saturation for all group comparisons were statistically significant (p CONCLUSION: HSI was able to differentiate among three discrete levels of burn injury. This is likely due to its correlation with skin perfusion: superficial burn injury causes an inflammatory response and increased perfusion to the burn site, while deeper burns destroy the dermal microvasculature and a decrease in perfusion follows. This study supports further investigation in the use of HSI in early burn depth assessment

    Temperature effect on the temporal dynamic of terrestrial invertebrates in technosols formed after reclamation at a post-mining site in Ukrainian steppe drylands

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    The research was carried out at the Research Centre of the Dnipro State Agrarian and Economic University in Pokrov city. Sampling was carried out in 2013–2015 on a variant of artificial soil (technosols) formed on loess-like loam, red-brown clay, green-grey clay, technological mixture of rocks, and also formed on loess-like loam with a humus-rich 70 cm top soil layer. To investigate the spatiotemporal variation in the abundance, species richness and species composition of invertebrate assemblages within the experimental polygon, the animals were sampled using pitfall traps. In total, 60 pitfall traps were operated simultaneously during each sampling period. Each year the pitfalls were emptied 26 times every 7–9 days. Invertebrates (Arthropoda and Mollusca) of 6 classes, 13 orders, 50 families and 202 species or parataxonomic units were recorded. Diplopoda was most abundant taxonomic group, though it was represented by only one species Rossiulus kessleri (Lohmander, 1927). Coleoptera and Araneae were the most numerous taxonomic groups. Readily available water for plants, precipitation, wind speed, atmospheric temperature (daily minimum, daily maximum, daily mean), atmospheric humidity and atmospheric pressure were used as environmental predictors. Two dimension geographic coordinates of the sampling locations were used to generate a set of orthogonal eigenvector-based spatial variables. Time series of sampling dates were used to generate a set of orthogonal eigenvector-based temporal variables. The moisture content in the technosols was revealed to be the most important factor determining the temporal dynamics of the terrestrial invertebrate community in conditions of semi-arid climate and the ecosystem which formed as a result of the reclamation process. Following soil moisture, the factor most strongly affecting invertebrates in the technosols was temperature. From the total set of the invertebrates, two relatively homogeneous species groups in terms of thermal preferences were extracted: the microtemperature and mesotemperature groups. The microtemperature species are more tolerant to the thermal factor, and the mesotemperature species are more sensitive. The Huisman-Olff-Fresco approach expanded by Jansen-Oksanen provides a wide set of ecologically relevant models which are able to explain species response. The species response to temperature is affected by a complex of other environmental, temporal and spatial factors. The effect of other factors on the species response must be previously extracted to find real estimations of the species temperature optima and tolerance. The approaches to solving this problem may be the object of future investigation

    Temporal aspect of the terrestrial invertebrate response to moisture dynamic in technosols formed after reclamation at a post-mining site in ukrainian steppe drylands

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    Different approaches were applied to assess soil moisture optima and tolerance of the ecological niche temporal projection of terrestrial invertebrates within an experimental polygon created to investigate the reclamation processes after deep underground hard-rock mining in the Ukrainian steppe drylands. Sampling was carried out in 2013–2015 on a variant of artificial soil (technosols). To investigate the spatiotemporal variation in the abundance, species richness and species composition of invertebrate assemblages the animals were sampled using pitfall traps. The readily available water for plants, precipitation, wind speed, atmospheric temperature, atmospheric humidity, and atmospheric pressure were used as environmental predictors. The two-dimension geographic coordinates of the sampling locations were used to generate a set of orthogonal eigenvector-based spatial variables. Time series of sampling dates were used to generate a set of orthogonal eigenvector-based temporal variables. Weighted averaging, generalized linear mixed models, Huisman-Olff-Fresco models expanded by Jansen-Oksanen, correspondence analysis, and constrained correspondence analysis were used to estimate soil moisture species optima and tolerance. The moisture content in the technosols was revealed to be the most important factor determining the temporal dynamics of terrestrial invertebrate community in conditions of semi-arid climate and the ecosystem which formed as a result of the reclamation process. The species response to the soil water content is affected not only by the soil water content but also by the complex of the other environmental, temporal, and spatial factors. The effect of other factors on the species response must be extracted previously to find real estimations of the species optima and tolerance

    The response of invertebrate communities to a moisture gradient in artificial soils of Ukrainian steppe arid zone

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    Animals were sampled within the experimental area using traps to investigate the spatial and temporal variation in abundance, species richness, and species composition of invertebrate communities. A total of 60 traps were operated simultaneously during each sampling period. Traps were emptied 26 times every 7-9 days each year. Plant water availability, precipitation, wind speed, air temperature (minimum, maximum, daily mean), air humidity, and atmospheric pressure were used as ecological predictors of invertebrate community status and structure. Two-dimensional geographic coordinates of sampling locations were used to create a set of orthogonal spatial variables based on eigenvectors. We used time series of sampling dates to produce a set of orthogonal eigenvector time variables. The moisture content in technosols was the most important factor determining the terrestrial invertebrate community's temporal dynamics under semi-arid climate and reclaimed ecosystem conditions. Each ecological group of terrestrial invertebrates is homogeneous in terms of moisture gradient (xerophilic, xerozoophilic, mesophilic) and has a specific set of patterns best explain the species response to water content in technosols. However, one should consider the fact that the species response to soil water content is influenced not only by soil water content but also by a complex of other environmental, temporal and spatial factors. That is why the effect of other factors on the species response must be extracted previously to find real estimations of the species optima and tolerance. This task can be solved using the constrained correspondence analysis (CCA) or constrained redundancy analysis (RDA) depending on the type of response to ecological factors prevailing in the community – monotone or unimodal. We found that in more dry conditions, the prevalent species responses are unimodal asymmetric, in moister – bimodal, and in moderate conditions, the distributions are symmetric unimodal. The asymmetric species response to soil moisture in different parts of the soil humidity range may be assumed as predominantly due to the abiotic factors in the gradient's aridest margin and due predominantly to the biotic factors in the most humid margin of the gradient. Keywords: species response, niche, optima, tolerance, reclamation, gradient, temporal dynami

    An assessment of pulse transit time for detecting heavy blood loss during surgical operation

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    Copyright @ Wang et al.; Licensee Bentham Open. This is an open access article licensed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.The main contribution of this paper is the use of non-invasive measurements such as electrocardiogram (ECG) and photoplethysmographic (PPG) pulse oximetry waveforms to develop a new physiological signal analysis technique for detecting blood loss during surgical operation. Urological surgery cases were considered as the control group due to its generality, and cardiac surgery as experimental group since it involves blood loss and water supply. Results show that the control group has the tendency of a reduction of the pulse transient time (PTT), and this indicates an increment in the blood flow velocity changes from slow to fast. While for the experimental group, the PTT indicates high values during blood loss, and low values during water supply. Statistical analysis shows considerable differences (i.e., P <0.05) between both groups leading to the conclusion that PTT could be a good indicator for monitoring patients' blood loss during a surgical operation.The National Science Council (NSC) of Taiwan and the Centre for Dynamical Biomarkers and Translational Medicine, National Central University, Taiwan

    Translational Model for External Volume Expansion in Irradiated Skin

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    Introduction: External Volume Expansion (EVE) treatment has gained popularity in breast reconstruction, enriching recipient sites for fat grafting. For patients receiving radiotherapy (XRT), results of EVE use vary, partly because the effects of EVE on irradiated tissue are not well understood. Based on our previous work with EVE and XRT, we developed a new translational model to investigate the effects of EVE in the setting of chronic radiation skin injury. Methods: Twenty-Eight SKH1-E mice received 50Gy of beta-radiation to each flank. Animals were monitored until chronic radiation fibrosis developed (8 weeks). EVE was then applied to one side for 6hrs on 5 consecutive days. The opposite side served as control. Hyperspectral Imaging (HSI) was used to assess perfusion changes before and after EVE. Mice were sacrificed at 5 days (n=14) and 15 days (n=14) after last application for histological analysis. Tissue samples were stained for vascularity (CD31) and collagen composition (Picro-Sirius red). Results: All animals developed skin fibrosis 8 weeks post-radiation, and changes in perfusion verified skin damage. EVE application induced edema on treated sides. Five days post-application, both sides were hypo-perfused as seen by HSI; with the EVE side 13% more ischemic than the untreated side (p\u3c0.001). Perfusion returned to control side levels by day 15. Blood vessels increased 20% by day 5 in EVE versus control. Collagen composition showed no difference in scar index analysis. Conclusion: EVE temporarily augments radiation-induced hypo-perfusion, likely due to transient edema. Fibrosis remained unchanged after EVE, possibly accounting for the limited expansion seen in patients. It appears that EVE induces angiogenic effect but does not affect dermal collagen composition. Future efforts should focus on reducing fibrosis post radiation to allow EVE to achieve its full potential, to benefit irradiated patients

    The temporal dynamics of readily available soil moisture for plants in the technosols of the Nikopol Manganese Ore Basin

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    The restoration of a stable and productive ecosystem after drastic disturbances to the natural environment due to mining and open-cast mining may be achieved by means of reclamation. Investigation of the hydrological budget of technosols is important task in developing adequate approaches to reclamation. Sod lithogenic soils on red-brown clay, on grey-green clay were chosen as the objects of the investigation. The simulation of moisture content in Nikopol Manganese Ore Basin technosols was performed using the Penman-Monteith approach and evaluated the role of the dependence of soils’ surface albedo on the humidity in the intensity of evapotranspiration. The research was conducted during 2013–2015 at the station for research on reclaimed land within the Nikopol Manganese Ore Basin (city Pokrov, Ukraine). The experimental area for the study of optimal modes of agricultural reclamation was created in 1968–1970. Precipitation in the investigated area was found to fall very unevenly in time. In 2013, the duration of the rainless period was 259 days, in 2014 – 264 days, in 2015 – 261 days. The maximum daily rainfall varies within 18–49 mm. There are significant interannual differences in the intensity of rainfall. The minimum total annual precipitation in 2014 was due to a decrease in atypical rainfall in late winter and early winter. The maximum annual rainfall in 2015 was caused by intense rainfall both in the spring and in mid-summer and late autumn. The average annual temperature was 11.1 ºC and the annual totals did not statistically significantly vary within the study period. The average wind speed and average atmospheric humidity are statistically significantly different from year to year. The technosols’ colour properties and surface albedo varied depending on the moisture content. There is a linear relationship between the moisture content in the soil and albedo of the soil surface. The evaluation of readily available water content was carried out based on the Penman-Monteith model taking into account meteorological data, the water-physical properties of the technosols and the dependence of soil surface albedo on soil humidity. The distribution of this index for different teсhnosols is characterized by a high level of similarity of shape due to the fact that the overall climate factors are crucial in shaping the dynamics of moisture. A complex mixture of normal distributions is the best model for representing the experimental data. The readily available water content distribution can best be represented as a mixture of two normal distributions. The relatively high moisture level is characterized for winter and spring periods. Water content in sodlithogenic soils on red-brown clay over the period of research never reached the value of the permanent wilting point. In 2013, the period when the moisture content was less than the value of the permanent wilting point lasted 23 days, and in 2014 this period lasted 39 days. Thus, you can always expect the phenomenon of drought under typical climatic conditions for the technosols on grey-green clay. It was found that monitoring water supplies before the start of the growing season can provide valuable information necessary for the selection of crops for cultivation in the current year. The results indicate the urgency of measures to save the winter rainfall on the fields. Keywords: reclamation; water regime; albedo; evapotranspiration; Penman-Monteith equation

    The temporal dynamics of readily available soil moisture for plants in the technosols of the Nikopol Manganese Ore Basin

    Get PDF
    The restoration of a stable and productive ecosystem after drastic disturbances to the natural environment due to mining and open-cast mining may be achieved by means of reclamation. Investigation of the hydrological budget of technosols is important task in developing adequate approaches to reclamation. Sod lithogenic soils on red-brown clay, on grey-green clay were chosen as the objects of the investigation. The simulation of moisture content in Nikopol Manganese Ore Basin technosols was performed using the Penman-Monteith approach and evaluated the role of the dependence of soils’ surface albedo on the humidity in the intensity of evapotranspiration. The research was conducted during 2013–2015 at the station for research on reclaimed land within the Nikopol Manganese Ore Basin (city Pokrov, Ukraine). The experimental area for the study of optimal modes of agricultural reclamation was created in 1968–1970. Precipitation in the investigated area was found to fall very unevenly in time. In 2013, the duration of the rainless period was 259 days, in 2014 – 264 days, in 2015 – 261 days. The maximum daily rainfall varies within 18–49 mm. There are significant interannual differences in the intensity of rainfall. The minimum total annual precipitation in 2014 was due to a decrease in atypical rainfall in late winter and early winter. The maximum annual rainfall in 2015 was caused by intense rainfall both in the spring and in mid-summer and late autumn. The average annual temperature was 11.1 ºC and the annual totals did not statistically significantly vary within the study period. The average wind speed and average atmospheric humidity are statistically significantly different from year to year. The technosols’ colour properties and surface albedo varied depending on the moisture content. There is a linear relationship between the moisture content in the soil and albedo of the soil surface. The evaluation of readily available water content was carried out based on the Penman-Monteith model taking into account meteorological data, the water-physical properties of the technosols and the dependence of soil surface albedo on soil humidity. The distribution of this index for different teсhnosols is characterized by a high level of similarity of shape due to the fact that the overall climate factors are crucial in shaping the dynamics of moisture. A complex mixture of normal distributions is the best model for representing the experimental data. The readily available water content distribution can best be represented as a mixture of two normal distributions. The relatively high moisture level is characterized for winter and spring periods. Water content in sod-lithogenic soils on red-brown clay over the period of research never reached the value of the permanent wilting point. In 2013, the period when the moisture content was less than the value of the permanent wilting point lasted 23 days, and in 2014 this period lasted 39 days. Thus, you can always expect the phenomenon of drought under typical climatic conditions for the technosols on grey-green clay. It was found that monitoring water supplies before the start of the growing season can provide valuable information necessary for the selection of crops for cultivation in the current year. The results indicate the urgency of measures to save the winter rainfall on the fields. Keywords: reclamation; water regime; albedo; evapotranspiration; Penman-Monteith equation
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