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Journal articles on the topic 'Skin contact experiment'
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1
Wu, Haibin, Yixian Su, Jinjin Shi, Jinwen Li, and Jinhua Ye. "A new robot skin for force and position detection." Industrial Robot: An International Journal 41, no. 6 (October 20, 2014): 534–42. http://dx.doi.org/10.1108/ir-07-2014-0369.
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Purpose – The aim of the research is to achieve a robot skin which is easy to use, and can detect both position and force interacted between robot and environments. Design/methodology/approach – The new type of robot skin proposed in this paper includes two functional modules – contact position sensor and contact force sensor. The contact position sensor module is based on the resistor divider principle, which consists of two perpendicular conductive fiber layers and insulated dot spacer between them. The contact force sensor module is based on capacitance change theory, which consists of two soft conductive plates and a viscoelastic layer between them. By combining the two modules, the soft robot skin was designed. Findings – Simulation and experiment results demonstrate that the proposed robot skin design is feasible and effective enough to sense contact position and contact force simultaneously. Practical implications – This robot skin is low-cost and easy to make and use, which provides safety solutions for most of the robot. Originality/value – For the first time, an integrated robot skin which can get contact position and force information simultaneously is designed. Unlike general tactile sensor matrices, this robot skin has only six leads. Furthermore, the number of leads does not increase with the enlarging of sensor area. Soft and simple structure of the robot skin makes it possible to cover any region of the robot body.
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Sun, Zhong Sheng, Liang Peng Kou, Yue Tong Qiu, and Xiao Ning Li. "Experiment of Finger Deformation by Pneumatic Nozzle." Applied Mechanics and Materials 220-223 (November 2012): 1723–26. http://dx.doi.org/10.4028/www.scientific.net/amm.220-223.1723.
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In order to study the relation between tactile sense and finger pad deformation during a tactile exploration task, a non-contact technique to measure the finger pad deformation was proposed in this paper. The finger pad deformation can be measured with high temporal and spatial resolution via laser displacement sensor installed on an XY movement workbench. The experimental results of the finger pad deformation in different conditions show that the characteristic of finger skin is viscoelastic. The parameters of viscoelastic model can be calculated by fitting method using the Kelvin model. They are helpful for modeling the mechanoreceptor responses in skin to improve the understanding of the mechanical behavior of the finger pad and of the relation between mechanical stimuli and tactile perception.
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Reynolds, Andrew G., Douglas A. Wardle, and Marjorie Dever. "Terpene Response to Pressing, Harvest Date, and Skin Contact in Vitis vinifera." HortScience 28, no. 9 (September 1993): 920–24. http://dx.doi.org/10.21273/hortsci.28.9.920.
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Vitis vinifera L. cultivars Müller-Thurgau, Muscat Ottonel, Gewürztraminer, and Kerner were studied for 1 year to document changes in fruit terpene levels from berry stage to free-run and press-juice stages. Substantial amounts of free volatile terpenes (FVTs) and potentially volatile terpenes (PVTs) were lost between berry and juice stages. PVTs were higher in press juices of `Gewürztraminer' and `Muscat Ottonel' than in free-run juices. In another experiment, juices from `Miiller-Thurgau', `Muscat Ottonel', `Kerner', `Optima', `Pearl of Csaba', and `Siegerrebe', harvested 10 to 20 days after a designated initial harvest date, contained higher FVTs and PVTs than initially. A third experiment with `Kerner', `Müller-Thurgau', `Optima', and `Siegerrebe' found highest FVTs and PVTs in juices from grapes subjected to skin contact compared with grapes crushed and immediately pressed. Sensory evaluation showed aroma differences between wines from free-run and press juices of `Miiller-Thurgau' and `Muscat Ottonel', aroma and flavor differences due to harvest date for all cultivars except `Pearl of Csaba', and aroma and flavor differences due to skin contact for `Siegerrebe'.
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Yamada, Daisuke, Takashi Maeno, and Yoji Yamada. "Artificial Finger Skin having Ridges and Distributed Tactile Sensors used for Grasp Force Control." Journal of Robotics and Mechatronics 14, no. 2 (April 20, 2002): 140–46. http://dx.doi.org/10.20965/jrm.2002.p0140.
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An artificial elastic finger skin for robot fingers has been developed for controlling grasp force when weight and frictional coefficient of the grasped object are unknown. The elastic finger skin has ridges at the surface to divide the stick/slip area. It also has a pair of tactile sensors embedded per ridge similar to human fingertips. The surface of the whole finger is curved so that reaction force distributes. A Finite Element (FE) model of the elastic finger skin was made to conduct dynamic contact analysis using a FE method to design the elastic finger skin in detail. Then the elastic finger skin was made. We confirmed by calculation and experiment that incipient slippage of the ridge occurring near the edge of contact is detected. Then, grasp was controlled using the finger. Arbitrary objects were lifted by incipient slippage near the edge of contact. We found that artificial finger skin is useful for controlling grasping force when the weight and friction coefficient between the elastic finger skin and grasping object are unknown.
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Raccuglia, Margherita, Kolby Pistak, Christian Heyde, Jianguo Qu, Ningtao Mao, Simon Hodder, and George Havenith. "Human wetness perception of fabrics under dynamic skin contact." Textile Research Journal 88, no. 19 (July 5, 2017): 2155–68. http://dx.doi.org/10.1177/0040517517716905.
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This experiment studied textile (surface texture, thickness) and non-textile (local skin temperature changes, stickiness sensation and fabric-to-skin pressure) parameters affecting skin wetness perception under dynamic interactions. Changes in fabric texture sensation between WET and DRY states and their effect on pleasantness were also studied. The surface texture of eight fabric samples, selected for their different structures, was determined from surface roughness measurements using the Kawabata Evaluation System. Sixteen participants assessed fabric wetness perception, at high pressure and low pressure conditions, stickiness, texture and pleasantness sensation on the ventral forearm. Differences in wetness perception (p < 0.05) were not determined by texture properties and/or texture sensation. Stickiness sensation and local skin temperature drop were determined as predictors of wetness perception (r2 = 0.89), and although thickness did not correlate with wetness perception directly, when combined with stickiness sensation it provided a similar predictive power (r2 = 0.86). Greater (p < 0.05) wetness perception responses at high pressure were observed compared with low pressure. Texture sensation affected pleasantness in DRY (r2 = 0.89) and WET (r2 = 0.93). In WET, pleasantness was significantly reduced (p < 0.05) compared to DRY, likely due to the concomitant increase in texture sensation (p < 0.05). In summary, under dynamic conditions, changes in stickiness sensation and wetness perception could not be attributed to fabric texture properties (i.e. surface roughness) measured by the Kawabata Evaluation System. In dynamic conditions thickness or skin temperature drop can predict fabric wetness perception only when including stickiness sensation data.
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Li, Fengyu, Yasuhiro Akiyama, Xianglong Wan, Shogo Okamoto, and Yoji Yamada. "Measurement of Shear Strain Field in a Soft Material Using a Sensor System Consisting of Distributed Piezoelectric Polymer Film." Sensors 20, no. 12 (June 19, 2020): 3484. http://dx.doi.org/10.3390/s20123484.
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Measurement of the internal stress and strain distributions within soft materials is necessary in the field of skin contact safety. However, conventional interactive force sensors cannot efficiently obtain or estimate these distributions. Herein, a shear strain sensor system consisting of distributed built-in piezoelectric polyvinylidene fluoride (PVDF) polymer films was developed to measure the internal shear strain field of a soft material. A shear strain sensing model was mathematically established, based on the piezoelectricity and mechanical behavior of a bending cantilever beam, to explain the sensing principle. An experiment in three-dimensional measurement of the shear strain distribution within an artificial skin was designed and conducted to assess the sensitivity of the sensing model. This sensor system could visualize the shear strain field and was sensitive to different contact conditions. The measurement results agreed well with the results of numerical simulation of the substrate, based on contact mechanics. The proposed sensor system was confirmed to provide a new sensing method for the field of shape analysis. The sensor system can be applied to develop sufficiently sensitive electronic skin and can significantly contribute to skin damage analysis and skin contact safety assessment.
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Zhang, Youzhi, Zhengkang Lin, Xiaojun You, Xingping Huang, Jinhua Ye, and Haibin Wu. "A position-sensitive electronic skin based on boundary potential projection theory." Sensor Review 40, no. 1 (January 13, 2020): 130–40. http://dx.doi.org/10.1108/sr-10-2019-0243.
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Purpose This paper aims to report a flexible position-sensitive sensor that can be applied as large-area electronic skin over the stiff media. Design/methodology/approach The sensor uses a whole piezoresistive film as a touch sensing area. By alternately constructing two uniform electric fields with orthogonal directions in the piezoresistive film, the local changes in conductivity caused by touch can be projected to the boundary along the equipotential line under the constraint of electric field. Based on the change of boundary potential in the two uniform electric fields, it can be easy to determine the position of the contact area in the piezoresistive film. Findings Experiment results show the proposed tactile sensor is capable of detecting the contact position and classifying the contact force in real-time based on the changes of the potential differences on the boundary of the sensor. Practical implications The application example of using the sensor sample as a controller in shooting game is presented in this paper. It shows that the sensor has excellent touch sensing performance. Originality/value In this paper, a position-sensitive electronic skin is proposed. The experiment results show that the sensor has great application prospects in the field of interactive tactile sensing.
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Spaccasassi, Chiara, Ivana Frigione, and Angelo Maravita. "Bliss in and Out of the Body: The (Extra)Corporeal Space Is Impervious to Social Pleasant Touch." Brain Sciences 11, no. 2 (February 12, 2021): 225. http://dx.doi.org/10.3390/brainsci11020225.
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Slow, gentle stimulation of hairy skin is generally accompanied by hedonic sensations. This phenomenon, also known as (positive) affective touch, is likely to be the basis of affiliative interactions with conspecifics by promoting inter-individual bindings. Previous studies on healthy humans have demonstrated that affective touch can remarkably impact behavior. For instance, by administering the Rubber Hand Illusion (RHI) paradigm, the embodiment of a fake hand enhances after a slow, affective touch compared to a fast, neutral touch. However, results coming from this area are not univocal. In addition, there are no clues in the existing literature on the relationship between affective touch and the space around our body. To overcome these lacks, we carried out two separate experiments where participants underwent a RHI paradigm (Experiment 1) and a Visuo-Tactile Interaction task (Experiment 2), designed to tap into body representation and peripersonal space processing, respectively. In both experiments, an affective touch (CT-optimal, 3 cm/s) and neutral touch (CT-suboptimal, 18 cm/s) were delivered by the experimenter on the dorsal side of participants’ hand through a “skin to skin” contact. In Experiment 1, we did not find any modulation of body representation—not at behavioral nor at a physiological level—by affective touch. In Experiment 2, no visuo-tactile spatial modulation emerged depending upon the pleasantness of the touch received. These null findings are interpreted in the light of the current scientific context where the real nature of affective touch is often misguided, and they offer the possibility to pave the way for understanding the real effects of affective touch on body/space representation.
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Wang, Li Li, Dong Sheng Li, Xiao Qiang Li, Liang Wang, and Wei Jun Yang. "Coefficient of Friction for Aluminum Alloy Sheet in Contact with Polyurethane Rubber." Applied Mechanics and Materials 26-28 (June 2010): 320–25. http://dx.doi.org/10.4028/www.scientific.net/amm.26-28.320.
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Stretch forming process of aircraft skin over reconfigurable compliant tooling is a new technology in skin manufacturing. During this process, the coefficient of friction is important for modeling accurately the process of stretch forming. The objective of this research is to measure the coefficient of friction for aluminum alloy in contact with polyurethane rubber in reciprocal sliding. An orthogonal experimental design was used to reveal the impact of four factors on the coefficient of friction, including lubrication, normal load, aluminum alloy material and sliding velocity. It is shown that lubrication is a major factor, sliding velocity is a minor factor. The influence of normal pressure is less than sliding velocity and the influence of aluminum alloy material is not very obvious. Finally, based on the experiment results, the selections of lubricant and stretching velocity are discussed in order to improve the process of stretch forming.
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Su, Yun, Jiazhen He, and Jun Li. "A model of heat transfer in firefighting protective clothing during compression after radiant heat exposure." Journal of Industrial Textiles 47, no. 8 (April 11, 2016): 2128–52. http://dx.doi.org/10.1177/1528083716644289.
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This paper presents an experiment-based, multi-medium heat transfer model to study thermal responses of multi-layer protective clothing with an air gap exposed to thermal radiation and hot contact surface. The model considers the dynamical changes of air gap, each layer’s fabric thickness, and air content contained in the fabric due to the pressure applied. The fabric heat transfer model developed from this study was incorporated into a human skin burn model in order to predict skin burn injuries. The predicted results from the model were well in agreement with the experimental results. A parametric study was conducted using various contact temperatures and applied pressures and design variables of firefighting protective clothing, such as physical properties of fabric layers and air gap sizes. It was concluded from the parametric study that resistance to transmission of injurious levels of heat decreases as the test temperature and contact pressure increase, and the contact heat transfer can weaken the importance of air gap under radiant heat flux(8.5 kW/m2) for 60 s and compression (pressure: 3 kPa, temperature: 316℃) for 60 s. The findings obtained in this study can be used to engineer fabric systems that provide better protection for contact heat exposure.
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Mandys, Tomáš, Vladislav Laš, Tomáš Kroupa, and Robert Zemčík. "Experimental and Numerical Investigation of Response of Sandwich Composite Beam Subjected to Low-Velocity Impact." Applied Mechanics and Materials 732 (February 2015): 239–46. http://dx.doi.org/10.4028/www.scientific.net/amm.732.239.
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This paper deals with the progressive failure analysis of sandwich composite beam loaded with transversely low-velocity impact. A user defined material model was used for modeling of the non-linear orthotropic elastic behavior of composite skin. The non-linear behavior of foam core was modeled using Low-Density Foam material model. The numerical model was validated using performed experiment and the results in terms of deflection and contact force time dependencies are mutually compared.
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Panta, YR, and Y. Poudyal. "A case report of a self-reproduced case of Paederus dermatitis." Journal of Universal College of Medical Sciences 1, no. 4 (January 12, 2014): 48–52. http://dx.doi.org/10.3126/jucms.v1i4.9575.
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Many cases of irritant contact dermatitis are noted every year in the students residing at the Universal College of Medical Science (UCMS) Hostel, Bhairahawa. The exact etiology of the disease was not confirmed but the suspect was an insect Paederus', commonly referred to as 'acid fly' in UCMS. However, none of the patients ever gives the clear cut history about the time of contact with the insect after noticing the lesion. So, an experiment was performed by crushing the suspected insect on the skin of the flexor aspect of the forearm and the reactions produced on the skin and the symptoms were noted every 12 hourly till the primary lesion was formed. Erythematous papules were formed initially that passed through different stages to form an erythematous plaque with many vesicles that suppurated to form sterile pustules. This resembled the common lesions observed in the students. It was confirmed that the irritant contact dermatitis observed in the students residing at the UCMS hostel is Paederus dermatitis. The clinical course of this dermatitis was also revealed experimentally. DOI: http://dx.doi.org/10.3126/jucms.v1i4.9575 Journal of Universal College of Medical Sciences (2013) Vol.1 No.04: 48-52
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Pang, Gaoyang, Jia Deng, Fangjinhua Wang, Junhui Zhang, Zhibo Pang, and Geng Yang. "Development of Flexible Robot Skin for Safe and Natural Human–Robot Collaboration." Micromachines 9, no. 11 (November 5, 2018): 576. http://dx.doi.org/10.3390/mi9110576.
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For industrial manufacturing, industrial robots are required to work together with human counterparts on certain special occasions, where human workers share their skills with robots. Intuitive human–robot interaction brings increasing safety challenges, which can be properly addressed by using sensor-based active control technology. In this article, we designed and fabricated a three-dimensional flexible robot skin made by the piezoresistive nanocomposite based on the need for enhancement of the security performance of the collaborative robot. The robot skin endowed the YuMi robot with a tactile perception like human skin. The developed sensing unit in the robot skin showed the one-to-one correspondence between force input and resistance output (percentage change in impedance) in the range of 0–6.5 N. Furthermore, the calibration result indicated that the developed sensing unit is capable of offering a maximum force sensitivity (percentage change in impedance per Newton force) of 18.83% N−1 when loaded with an external force of 6.5 N. The fabricated sensing unit showed good reproducibility after loading with cyclic force (0–5.5 N) under a frequency of 0.65 Hz for 3500 cycles. In addition, to suppress the bypass crosstalk in robot skin, we designed a readout circuit for sampling tactile data. Moreover, experiments were conducted to estimate the contact/collision force between the object and the robot in a real-time manner. The experiment results showed that the implemented robot skin can provide an efficient approach for natural and secure human–robot interaction.
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Matar, Hazem, Andreia Pinhal, Nevine Amer, Mark Barrett, Elliot Thomas, Philip Hughes, Joanne Larner, and Robert P. Chilcott. "Decontamination and Management of Contaminated Hair following a CBRN or HazMat Incident." Toxicological Sciences 171, no. 1 (June 26, 2019): 269–79. http://dx.doi.org/10.1093/toxsci/kfz145.
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Abstract This in vitro study evaluated the “triple protocol” of dry decontamination, the ladder pipe system (a method for gross decontamination), and technical decontamination for the decontamination of hair following chemical contamination. First, we assessed the efficacy of the 3 protocols, alone or in combination, on excised porcine skin and human hair contaminated with either methyl salicylate (MS), phorate (PHR), sodium fluoroacetate (SFA), or potassium cyanide (KCN). A second experiment investigated the residual hair contamination following decontamination with the triple protocol at different intervals postexposure. In a third experiment, hair decontaminated after exposure to MS or PHR was evaluated for off-gassing. Though skin decontamination was highly effective, a substantial proportion (20%–40%) of the lipophilic compounds (MS and PHR) remained within the hair. The more water-soluble contaminants (SFA and KCN) tended to form much smaller reservoirs within the hair. Interestingly, substantial off-gassing of MS, a medium volatility chemical, was detectable from triple-decontaminated hair up to 5 days postexposure. Overall, the decontamination strategies investigated were effective for the decontamination of skin, but less so for hair. These findings highlight the importance of contaminated hair serving as a source of potential secondary contamination by contact or inhalation. Therefore, consideration should be given to the removal of contaminated hair following exposure to toxic chemicals.
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Shi, Chen, Ping Liu, Yu He, Yongwei Liu, Xiaobo Feng, and Dehao Fu. "Drug-loaded poly(d,l-lactide-co-glycolide) microspheres as treatment for allergic contact dermatitis in mice model." Journal of Bioactive and Compatible Polymers 32, no. 5 (March 23, 2017): 445–55. http://dx.doi.org/10.1177/0883911517690759.
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Allergic contact dermatitis is a common skin disease and the current treatment always along with frequent medication and side effect. In this research, poly(d,l-lactide- co-glycolide) microspheres encapsulating tacrolimus are first employed as a therapy of allergic contact dermatitis in mice model by subcutaneous injection. Allergic contact dermatitis is successfully induced in BALB/c mice by repeated painting of dinitrofluorobenzene on mice ear. Tacrolimus is efficiently encapsulated into poly(d,l-lactide- co-glycolide) microspheres by emulsion evaporation method, and then the microspheres are subcutaneously injected into dermatitis-suffered BALB/c mice. We find that the dermatitis mice treated with tacrolimus-loaded microspheres get a sustained suppression on ear swelling, dermatitis index, inflammatory cell accumulation, and serum immunoglobulin E concentration. The curative effect of tacrolimus-loaded microspheres is similar to daily tacrolimus injection and is even better in the inhibition of ear swelling. Dermatitis mice treated with blank microspheres get no curative effect during the whole experiment. The data suggest that subcutaneous injection of drug-loaded microspheres could be a potential candidate for the management of allergic contact dermatitis.
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Lin, Yinglei, Yi Li, Lei Yao, Guoru Zhao, and Lei Wang. "Effects of deep knee flexion on skin pressure profile with lower limb device: A computational study." Textile Research Journal 90, no. 17-18 (February 9, 2020): 1962–73. http://dx.doi.org/10.1177/0040517520902275.
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Knee flexion behavior alters the contact pressure distribution exerted by compression devices during exercise. This study aimed to develop a three-dimensional dynamic finite element model of the lower limb with detailed bony structures, wearing a compression device with higher pressure over the calf, and then to quantify and compare the garment–body interface contact pressure and the cross-section pressure gradient deviation in standing and deep knee flexion postures (30°, 60°, 90°, and 120° of knee flexion). Contact pressure experiment on seven muscle points was applied to validate the model. The cross-section pressure gradient deviation was calculated on landmarks based on deviation along the four axial pathways from the average cross-section pressure gradients. In general, the results demonstrated that the whole pressure profile gradually decreased from the ankle to the thigh with higher compression on the calf in a standing position. Cross-section pressure gradient deviation resulted in a dramatic increase of ∼100% and ∼110% on positions B1 and D on the anterior of calf at 60° flexion, respectively, which resembled an M shape. This phenomenon was caused by the combination of the stretch of clothing during knee flexion, high compression over the calf, and the shape of the lower limb. This finite element model and its findings together could help us to understand the compression effects of sports lower limb devices and garments to enhance walking and running performance, and help to improve the design concepts.
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McKenzie, Christina M., Paul T. Oesterle, Brian Stevens, Leonard Shirose, Gabriela F. Mastromonaco, Brandon N. Lillie, Christina M. Davy, Claire M. Jardine, and Nicole M. Nemeth. "Ophidiomycosis in Red Cornsnakes (Pantherophis guttatus): Potential Roles of Brumation and Temperature on Pathogenesis and Transmission." Veterinary Pathology 57, no. 6 (August 31, 2020): 825–37. http://dx.doi.org/10.1177/0300985820953423.
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Ophidiomycosis (snake fungal disease) is caused by the fungus Ophidiomyces ophiodiicola. As ophidiomycosis is difficult to study in free-ranging snakes, a reliable experimental model is needed to investigate transmission, pathogenesis, morbidity, and mortality, and the effects of brumation and temperature on disease development. Our objective was to develop such a model via subcutaneous injection of O. ophiodiicola conidia in red cornsnakes ( Pantherophis guttatus). The model was used to evaluate transmission and the effects of brumation and temperature in co-housed inoculated and noninoculated snakes. All 23 inoculated snakes developed lesions consistent with ophidiomycosis, including heterophilic and granulomatous dermatitis, cellulitis, and myositis, and embolic fungal granulomas throughout the liver and the coelomic connective tissue in 21/23 (91%). In the inoculated snakes, 21% of skin swabs, 37% of exuvia, and all liver samples tested positive by qPCR (quantitative polymerase chain reaction) for O. ophiodiicola. A post brumation skin swab from 1/12 noninoculated snakes that brumated in contact with inoculated snakes tested positive by qPCR, suggesting possible contact transmission. That snake had microscopic skin lesions consistent with ophidiomycosis, but no visible fungal elements. Of the 23 inoculated snakes, 20 (87%) died over the 70-day experiment, with ophidiomycosis considered the primary cause of death; 12 (52%) of the inoculated snakes died during brumation. Overall, this experimental model of ophidiomycosis reproduced skin lesions analogous to those of many natural cases, and internal lesions similar to the most severe natural cases. The study provides tentative experimental evidence for horizontal transmission in brumation, and offers a tool for future studies of this widespread snake disease.
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Wei, Yuyang, Zhenmin Zou, Guowu Wei, Lei Ren, and Zhihui Qian. "Subject-Specific Finite Element Modelling of the Human Hand Complex: Muscle-Driven Simulations and Experimental Validation." Annals of Biomedical Engineering 48, no. 4 (December 16, 2019): 1181–95. http://dx.doi.org/10.1007/s10439-019-02439-2.
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AbstractThis paper aims to develop and validate a subject-specific framework for modelling the human hand. This was achieved by combining medical image-based finite element modelling, individualized muscle force and kinematic measurements. Firstly, a subject-specific human hand finite element (FE) model was developed. The geometries of the phalanges, carpal bones, wrist bones, ligaments, tendons, subcutaneous tissue and skin were all included. The material properties were derived from in-vivo and in-vitro experiment results available in the literature. The boundary and loading conditions were defined based on the kinematic data and muscle forces of a specific subject captured from the in-vivo grasping tests. The predicted contact pressure and contact area were in good agreement with the in-vivo test results of the same subject, with the relative errors for the contact pressures all being below 20%. Finally, sensitivity analysis was performed to investigate the effects of important modelling parameters on the predictions. The results showed that contact pressure and area were sensitive to the material properties and muscle forces. This FE human hand model can be used to make a detailed and quantitative evaluation into biomechanical and neurophysiological aspects of human hand contact during daily perception and manipulation. The findings can be applied to the design of the bionic hands or neuro-prosthetics in the future.
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Brewis, Deborah N., and Eley Williams. "Writing as skin: Negotiating the body in(to) learning about the managed self." Management Learning 50, no. 1 (September 28, 2018): 87–99. http://dx.doi.org/10.1177/1350507618800715.
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We draw on the notion of ‘skin’ to discuss the ways in which writing in management and organisation studies wrestles with two drives in its endeavour to represent the reality of our ‘organised’ lives: the drive to share internal lived experience, and the drive to externalise and abstract. Through exploring skin as a metaphor for a negotiating interface between these forces in our writing, we (a) argue that both are critical parts of writing, needed in order to learn about management and organisation and (b) explore different ways in which they might be brought into contact. Reviewing, synthesising and building on critiques of ‘scientific’ writing that have been made from within management and organisation studies, and on creative commentary from the arts, we think reflexively about the ways in which writing mediates learning by being both representative of experience and an experience in itself. A collaboration between management scholar and creative writer, the text of this article is a critical-creative experiment that outlines the experiential ‘skin-text’ while simultaneously producing an example of such a text.
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Yang, Zheng, Kazutaka Mitsui, Jianqing Wang, Takashi Saito, Shunsuke Shibata, Hiroyuki Mori, and Goro Ueda. "Non-Contact Heart-Rate Measurement Method Using Both Transmitted Wave Extraction and Wavelet Transform." Sensors 21, no. 8 (April 13, 2021): 2735. http://dx.doi.org/10.3390/s21082735.
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Continuous monitoring of heart-rate is expected to lead to early detection of physical discomfort. In this study, we propose a non-contact heart-rate measurement method which can be used in an environment such as driver heart-rate monitoring with body movement. The method is based on the electric field strength transmitted through the human body that changes with the diastole and systole of the heart. Unlike conventional displacement detection of the skin surface, we attempted to capture changes in the internal structure of the human body by irradiating the human body with microwaves and acquiring microwaves that pass through the heart. We first estimated the electric field strength transmitted through the heart using three receiving sensors to reduce the body movement effect. Then we decomposed the estimated transmitted electric field using stationary wavelet transform to eliminate significant distortion due to body movement. As a result, we achieved an estimation accuracy of heart-rate as high as 98% in a verification experiment with normal body movement.
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Abdolvahab, Mohammad. "Quantification of Subjective Scaling of Friction Using a Fingertip Biomechanical Model." Applied Bionics and Biomechanics 9, no. 3 (2012): 293–302. http://dx.doi.org/10.1155/2012/281406.
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Subjective scaling of friction is important in many applications in haptic technology. A nonhomogeneous biomechanical finite element model of fingertip is proposed in order to predict neural response of sensitive mechanoreceptors to frictional stimuli (Slowly Adapting SAII receptors under the glabrous skin). In a guided psychophysical experiment, ten human subjects were asked to scale several standard surfaces based on the perception of their frictional properties. Contact forces deployed during the exploratory time of one of the participants were captured in order to estimate required parameters for the model of contact in the simulation procedure. Consequently, the strain energy density at the location of a selective mechanoreceptor in the finite element model as a measure of discharge rate of the neural unit was compared to the subject’s perceptual evaluation of the relevant stimuli. It was observed that the subject’s scores correlate with the discharge rate of the given receptor.
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Martykanova, Dilyara, Ilya Zemlenuhin, Ollga Reshetnik, Dilyara Kamaldinova, and Nailya Davletova. "Sensitivity of staphylococcus microflora of wrestlers’ skin to bacteriophages." SCIENCE AND SPORT: current trends 7, no. 3 (September 2019): 136–41. http://dx.doi.org/10.36028/2308-8826-2019-7-3-136-141.
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The purpose of this study was to identify the characteristics of bacteriocenosis of wrestlers’ skin and to determine the sensitivity of staphylococcal microflora to bacteriophages. Methods and organization of the research. The experiment involved 15 athletes aged 17-21 years engaged in national wrestling and belt wrestling. Qualifications ranged from 1st adult rank to the master of sports. We used the method of microbiological seeding on yolk-salt agar (JSA) to analyze the washes from the intact skin of the medial part of forearms of wrestlers before and immediately after training. We identified the grown colonies of microorganisms using MALDI Microflex Biotyper mass-spectrometer (Bruker, Germany). In addition to the total microbial abundance, the frequency of occurrence of hemolytic forms of bacteria on wrestlers’ skin was determined before and after training. We determined the sensitivity of Staphylococcus aureus bacteria to staphylococcal bacteriophage and polyvalent pyobacteriophage by the diameter of the bacteria lysis zone. Results and discussion. The research revealed the following facts. 1) S. aureus appears more often than other staphylococci on the skin of the medial part of wrestlers’ forearms both before and after training. 2) We detected high frequency of occurrence of hemolytic forms of Staphylococcus bacteria, which indicates the dysbiosis of wrestlers’ skin. 3) It is more efficient to use a staphylococcal bacteriophage than polyvalent pyobacteriophage for the prevention and treatment of infectious diseases of wrestlers’ skin caused by S. aureus. Conclusion. Athletes of contact sports demonstrate an increased risk of skin infectious diseases, and they need effective means of protection and prevention.
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Aoyagi, Seiji, Kento Okuda, Tomokazu Takahashi, and Masato Suzuki. "Effect of Microneedle Cross-Sectional Shape on Puncture Resistance – Investigation of Polygonal and Star-Shaped Cross Sections –." Journal of Robotics and Mechatronics 32, no. 2 (April 20, 2020): 371–81. http://dx.doi.org/10.20965/jrm.2020.p0371.
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The shape of the needle tip that is currently used in the medical field is a “lancet point,” which is a diagonally cut cylindrical pipe, further cut on both sides. The shape of the needle shank is typically cylindrical. In this paper, tip and shank shapes that differ from the standard shape are experimentally investigated for the purpose of reducing puncture resistance. Microneedles of various cross-sectional shapes, such as polygonal and star-like, were fabricated using stereo laser lithography. Before the needle penetrates the skin, sharp edges at the needle tip may be effective to generate a stress concentration on the skin, inducing a skin fracture. After the needle penetrates the skin, corners in the cross section of the needle shank may effectively reduce the frictional resistance because the contact area between the skin and needle is limited at the corners. A needle insertion experiment was conducted against an artificial skin made of polydimethylsiloxane. The puncture resistance decreased respectively for the circular needle, polygonal needle, and star-shaped needle. For the star-shaped needles, the maximum resistance decreased as the number of corners (N) decreased. For the polygonal needle, the maximum resistance increased as N increased from 3 to 5; however, there was no observable difference for N from 6 to 8. The experimental results show that a triangular star-shaped microneedle is the most effective in reducing the puncture resistance.
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Law, Jennifer, Stevan Gilmore, and Scott Kelly. "Postflight Rash and Skin Sensitivity Following a Year-Long Spaceflight Mission." Aerospace Medicine and Human Performance 91, no. 7 (July 1, 2020): 604–7. http://dx.doi.org/10.3357/amhp.5580.2020.
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BACKGROUND: While skin conditions are commonly reported in flight on the International Space Station (ISS), postflight skin complaints have generally been limited to foot sole sensitivity upon reloading after landing. In this case report, we describe the postflight skin findings in NASA’s first year-long crewmember.CASE REPORT: The crewmember was a 51-yr-old astronaut who spent 340 d in space on this mission. His in-flight course was unremarkable except for medication use for congestion, likely secondary to microgravity-induced fluid shift and elevated CO2 levels on the ISS, and an episode of contact dermatitis from electrodes for an experiment. He had a nominal landing in Kazakhstan. During his direct return to Houston, approximately 10 h after the Soyuz landing, he developed erythema and skin sensitivity in gravity-dependent areas. The skin findings persisted for 6 d and were successfully treated with nonsteroidal anti-inflammatory drugs, gabapentin, hydrotherapy, and massage.DISCUSSION: While vascular, allergic, and immunologic causes cannot be ruled out, we hypothesize that a prolonged lack of skin stimulation over the course of the year-long mission led to the crewmember’s postflight rash and skin sensitivity. Previous studies have demonstrated alterations in cutaneous receptor feedback in the sole of the foot in spaceflight and, therefore, it is plausible that skin in other parts of the body can undergo similar changes if they are not stimulated as they normally would be on Earth. More work will be needed to better understand this phenomenon and test potential mitigations.Law J, Gilmore S, Kelly S. Postflight rash and skin sensitivity following a year-long spaceflight mission. Aerosp Med Hum Perform. 2020; 91(7):604–607.
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Habarugira, Gervais, Jasmin Moran, Agathe M. G. Colmant, Steven S. Davis, Caitlin A. O’Brien, Sonja Hall-Mendelin, Jamie McMahon, et al. "Mosquito-Independent Transmission of West Nile virus in Farmed Saltwater Crocodiles (Crocodylus porosus)." Viruses 12, no. 2 (February 11, 2020): 198. http://dx.doi.org/10.3390/v12020198.
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West Nile virus, Kunjin strain (WNVKUN) is endemic in Northern Australia, but rarely causes clinical disease in humans and horses. Recently, WNVKUN genomic material was detected in cutaneous lesions of farmed saltwater crocodiles (Crocodylus porosus), but live virus could not be isolated, begging the question of the pathogenesis of these lesions. Crocodile hatchlings were experimentally infected with either 105 (n = 10) or 104 (n = 11) TCID50-doses of WNVKUN and each group co-housed with six uninfected hatchlings in a mosquito-free facility. Seven hatchlings were mock-infected and housed separately. Each crocodile was rotationally examined and blood-sampled every third day over a 3-week period. Eleven animals, including three crocodiles developing typical skin lesions, were culled and sampled 21 days post-infection (dpi). The remaining hatchlings were blood-sampled fortnightly until experimental endpoint 87 dpi. All hatchlings remained free of overt clinical disease, apart from skin lesions, throughout the experiment. Viremia was detected by qRT-PCR in infected animals during 2–17 dpi and in-contact animals 11–21 dpi, indicating horizontal mosquito-independent transmission. Detection of viral genome in tank-water as well as oral and cloacal swabs, collected on multiple days, suggests that shedding into pen-water and subsequent mucosal infection is the most likely route. All inoculated animals and some in-contact animals developed virus-neutralizing antibodies detectable from 17 dpi. Virus-neutralizing antibody titers continued to increase in exposed animals until the experimental endpoint, suggestive of persisting viral antigen. However, no viral antigen was detected by immunohistochemistry in any tissue sample, including from skin and intestine. While this study confirmed that infection of saltwater crocodiles with WNVKUN was associated with the formation of skin lesions, we were unable to elucidate the pathogenesis of these lesions or the nidus of viral persistence. Our results nevertheless suggest that prevention of WNVKUN infection and induction of skin lesions in farmed crocodiles may require management of both mosquito-borne and water-borne viral transmission in addition to vaccination strategies.
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Hong, Seunghyeok, and Kwang Park. "Unobtrusive Photoplethysmographic Monitoring Under the Foot Sole while in a Standing Posture." Sensors 18, no. 10 (September 26, 2018): 3239. http://dx.doi.org/10.3390/s18103239.
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Photoplethysmography (PPG) of the foot sole could provide additional health-related information compared with traditional PPG of the finger or wrist. Previously, foot PPG required the procedural binding of a light-emitting diode (LED)-photodetector (PD) pair. We achieved PPG of the foot sole without binding any sensors to the foot while the participant stood in a natural standing position on the testing device. Foot PPG was performed using multiple LED-PD pairs to overcome motion artefacts caused by stabilization. We identified regions of the sole suitable for reliable sensor positioning with optimal LED-PD pairs on the basis of the estimated heart rate (HR) and signal quality index derived by dynamic time warping (wSQI). The first experiment included four participants with direct skin-to-sensor contact, and the results showed a mean HR estimation error of 0.01 beats/min and a wSQI of 0.909. The extended experiment with 53 participants, which involved including a gap between the skin and sensors to consider real-life applications, yielded a mean HR estimation error of 0.638 beats/min and a wSQI of 0.751. Based on the selection ratio of optimal LED-PD pairs, the best region of the sole for PPG was the midfoot, except the medial longitudinal arch. In conclusion, we confirmed that foot PPG using multiple LED-PD pairs is appropriate for HR evaluation and further applications.
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Aland, Rajkumar, Ganesan M, P. Rajeswara Rao, and Bhikshapathi D. V. R. N. "Solid Lipid Nanoparticles for Topical Delivery of Acitretin for the Treatment of Psoriasis by Design of Experiment." International Journal of Pharmaceutical Sciences and Nanotechnology 12, no. 2 (March 31, 2020): 4474–91. http://dx.doi.org/10.37285/ijpsn.2019.12.2.5.
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The main objective for this investigation is to develop and optimize the solid lipid nanoparticles formulation of acitretin for the effective drug delivery. Acitretin loaded SLNs were prepared by hot homogenization followed by the ultrasonication using Taguchi’s orthogonal array with eight parameters that could affect the particle size and entrapment efficiency. Based on the results from the analyses of the responses obtained from Taguchi design, three different independent variables including surfactant concentration (%), lipid to drug ratio (w/w) and sonication time (s) were selected for further investigation using central composite design. The lipid Dynasan-116, surfactant poloxomer-188 and co surfactant egg lecithin resulted in better percent drug loading and evaluated for particle size, zeta potential, drug entrapment efficiency, in vitro drug release and stability. All parameters were found to be in an acceptable range. TEM analysis has demonstrated the presence of individual nanoparticles in spherical shape and the results were compatible with particle size measurements. In vitro drug release of optimized SLN formulation (F2) was found to be 95.63 ± 1.52%, whereas pure drug release was 30.12 after 60 min and the major mechanism of drug release follows first order kinetics release data for optimized formulation (F2) with non-Fickian (anomalous) with a strong correlation coefficient (R2 = 0.94572) of Korsemeyer-Peppas model. The total drug content of acitretin gel formulation was found to 99.86 ± 0.012% and the diameter of gel formulation was 6.9 ± 0.021 cm and that of marketed gel was found to be 5.7 ± 0.06 cm, indicating better spreadability of SLN based gel formulation. The viscosity of gel formulation at 5 rpm was found to be 6.1 x 103 ± 0.4 x 103 cp. The release rate (flux) of acitretin across the membrane and excised skin differs significantly, which indicates about the barrier properties of skin. The flux value for SLN based gel formulation (182.754 ± 3.126 μg cm−2 h−1) was found to be higher than that for marketed gel (122.345 ± 4.786 μg cm−2 h−1). The higher flux and Kp values of SLN based gel suggest that it might be able to enter the skin easily as compared with marketed gel with an advantage of low interfacial tension of the emulsifier film that ensures an excellent contact to the skin. This topically oriented SLN based gel formulation could be useful in providing site-specific dermal treatment of psoriasis
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Shibasaki, Manabu, Narihiko Kondo, Hirotaka Tominaga, Ken Aoki, Eiichi Hasegawa, Yoshiyuki Idota, and Toshimichi Moriwaki. "Continuous measurement of tympanic temperature with a new infrared method using an optical fiber." Journal of Applied Physiology 85, no. 3 (September 1, 1998): 921–26. http://dx.doi.org/10.1152/jappl.1998.85.3.921.
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The purpose of this study was to investigate the utility of an infrared tympanic thermometry by using an optical fiber for measuring tympanic temperature (Tty). In the head cooling and facial fanning tests during normothermia, right Tty measured by this method (infrared-Tty) and esophageal temperature (Tes) were not affected by decreased temple and forehead skin temperatures, suggesting that the infrared sensor in this system measured the infrared radiation from the tympanic membrane selectively. Eight male subjects took part in passive-heat-stress and progressive-exercise tests. No significant differences among infrared-Tty, the left Tty measured by thermistor (contact-Tty), and Tes were observed at rest or at the end of each experiment, and there was no significant difference in the increase in these core temperatures from rest to the end. Furthermore, there were no significant differences in the core temperature threshold at the onset of sweating and slope (the relationship of sweating rate vs. infrared-Tty and vs. contact-Tty). These results suggest that this method makes it possible to measure Tty accurately, continuously, and more safely.
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Luze, Hanna, Judith Holzer, Katrin Tiffner, Sonja Kainz, Peter Reisenegger, Sebastian P. Nischwitz, Martin Funk, Thomas Birngruber, Selma Mautner, and Lars-Peter Kamolz. "615 Bacterial Nanocellulose as Cooling Agent." Journal of Burn Care & Research 41, Supplement_1 (March 2020): S152—S153. http://dx.doi.org/10.1093/jbcr/iraa024.241.
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Abstract Introduction Cooling of burn injuries is most important, not only to reduce pain but also to reduce the intradermal damage as well as the burn wound conversion. Studies have shown that cooling for about 20 to 30 minutes using only plain tap water at moderate temperature is most efficient resulting in least intradermal damage. However, many burn injuries reach the hospital without any pre-clinical cooling, possibly due to the lack of a cooling agent. After a pilot study, we investigated if a bacterial nanocellulose (BNC)-based wound dressing containing about 95% water can cool a burn injury and if so the effect suffices to reduce the damage in the skin. Methods Skin explants from human donors were burned with inflicted a contact burn injury, of which half were treated with a BNC-based wound dressing and a paraffin gauze dressing. Intradermal temperature sensors measured the temperature changes in the dermis over the course of 24 hours. Biopsies were taken for histological evaluation at different time points. Results The intradermal measurements show high temperature spikes at the moment of the burn injuries. After the application of a BNC-based wound dressing the intradermal skin temperature was significantly reduced. The area under the curve in the treated group was significantly less than the untreated. The histological assessment showed according results with less damage in the treated group in comparison to the untreated. Conclusions Bacterial nanocellulose-based wound dressings with high water content significantly lower the intradermal temperature after a contact burn and reduce the thermal damage inflicted to the skin. A secondary dressing that permits the water to evaporate slower additionally prolongs the cooling effect. The use of such a wound dressing could find use in a preclinical setting where other cooling options are not available. Applicability of Research to Practice The findings of this experiment should be tested in an in-vivo setting prior to clinical use to investigate the possibility of inducing hypothermia with this treatment.
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Chen, Huiling, Liguo Shuai, Weihang Zhu, and Mei Miao. "An investigation of stimuli-current thresholds on the non-steady contact condition." Industrial Robot: the international journal of robotics research and application 46, no. 3 (May 20, 2019): 351–59. http://dx.doi.org/10.1108/ir-11-2018-0230.
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Purpose This paper aims to investigate the perception threshold (PT) of electrotactile stimulation under non-steady contact condition (NSCC) which is rarely considered in previous reports mainly because of the difficulty with experimental control. Three factors of NSCC are involved, including the current alternating frequency, the tapping interval of stimulation and the stimulating area of skin. The study is aimed at providing the basic PT data for design and application of wearable and portable electrotactile device. Design/methodology/approach The up-down method was selected to assess PT, and 72 experimental scenarios were constructed. During the study, we developed an experimental platform with the function of data record and programmable current stimulation. With psychophysical experiment, more than 10,000 data were collected. Furthermore, statics analysis and ANOVA test were opted for exploring the main factor influencing PT. Findings NSCC has different PTs on each body location, and PT has a positive correlation with frequency. In general, PT in NSCC is significantly lower than that in SCC. In some cases, it can be lower by more than 60 per cent. In addition, women have a lower PT than men across all age groups, and the younger is generally more sensitive than the older in electro-sensation. Research limitations/implications Limited factors of NSCC were considered in this study. Contact time and break interval should be investigated in the future work. Practical implications The paper includes implications for the development of smart electrotactile device. Originality/value This paper fulfills a challenge in assessing the PT under NSCC.
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Tan, Yan Hao, Agarwal Hitesh, and King Ho Holden Li. "Application of Machine Learning Algorithm on MEMS-Based Sensors for Determination of Helmet Wearing for Workplace Safety." Micromachines 12, no. 4 (April 16, 2021): 449. http://dx.doi.org/10.3390/mi12040449.
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Appropriate use of helmets as industrial personal protective gear is a long-standing challenge. The dilemma for any user wearing a helmet is thermal discomfort versus the chances of head injuries while not wearing it. Applying helmet microclimate psychrometry, we propose a logistic regression- (LR) based machine learning (ML) algorithm coupled with low-cost and readily available MEMS sensors to determine if a helmet was worn (W) or not worn (NW) by a human user. Experiment runs involving human subject (S) and mannequin experiment control (C) groups were conducted across no mask (NM) and mask (M) conditions. Only ambient-microclimate humidity difference (AMHD) was a feasible parameter for helmet wearing determination with 71 to 85% goodness of fit, 72 to 76% efficacy, and distinction from control group. Ambient-microclimate humidity difference’s rate of change (AMHDROC) had high correlation to helmet wearing and removal initiations and was quantitatively better in all measures. However, its feasibility was doubtful for continuous use beyond 1 min due to plateauing AMHD response. Experiments with control groups and temperature measurement showed invariant response to helmet worn or not worn with goodness of fit and efficacy consolidation to 50%. Results showed the algorithm can make helmet-wearing determinations with combination of analysis and use of data that was individually authentic and non-identifiable. This is an improvement as compared to state of the art skin-contact mechanisms and image analytics methods in enabling safety enhancements through data-driven worker safety ownership.
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Nakamoto, Hiroyuki, Taketo Wakabayashi, Futoshi Kobayashi, and Fumio Kojima. "Estimation of Displacement and Rotation by Magnetic Tactile Sensor Using Stepwise Regression Analysis." Journal of Sensors 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/459059.
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The human is covered with soft skin and has tactile receptors inside. The skin deforms along a contact surface. The tactile receptors detect the mechanical deformation. The detection of the mechanical deformation is essential for the tactile sensation. We propose a magnetic type tactile sensor which has a soft surface and eight magnetoresistive elements. The soft surface has a permanent magnet inside and the magnetoresistive elements under the soft surface measure the magnetic flux density of the magnet. The tactile sensor estimates the displacement and the rotation on the surface based on the change of the magnetic flux density. Determination of an estimate equation is difficult because the displacement and the rotation are not geometrically decided based on the magnetic flux density. In this paper, a stepwise regression analysis determines the estimate equation. The outputs of the magnetoresistive elements are used as explanatory variables, and the three-axis displacement and the two-axis rotation are response variables in the regression analysis. We confirm the regression analysis is effective for determining the estimate equations through simulation and experiment. The results show the tactile sensor measures both the displacement and the rotation generated on the surface by using the determined equation.
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Wang, Bour-Jr, Hui-Wen Chiu, Yong-Lin Lee, Chia-Yi Li, Ying-Jan Wang, and Yu-Hsuan Lee. "Pterostilbene Attenuates Hexavalent Chromium-Induced Allergic Contact Dermatitis by Preventing Cell Apoptosis and Inhibiting IL-1β-Related NLRP3 Inflammasome Activation." Journal of Clinical Medicine 7, no. 12 (November 27, 2018): 489. http://dx.doi.org/10.3390/jcm7120489.
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Hexavalent chromium (Cr(VI)) is widely used in many industries but can induce contact dermatitis especially in cement industries. Many cement workers suffer from Cr(VI)-induced allergic contact dermatitis (ACD), and prevention and therapeutic strategies are still lacking. Pterostilbene (PT) is a natural compound predominantly found in blueberries. Studies indicate the potential use of PT as an effective anti-oxidative and anti-inflammatory agent. Herein, we investigated the possible mechanisms involved and whether chromium-induced ACD could be effectively inhibited by treating PT. In our in vivo study, epidermal Cr(VI) administration causes cutaneous inflammation in mice ear skin, and the pro-inflammatory cytokines, TNF-α and IL-1β, were found in the epidermis, presenting the level of increase after Cr(VI) treatment. Meanwhile, the results of our in vitro experiment showed that apoptosis and endoplasmic reticulum (ER) stress were induced after treatment with different concentrations of Cr(VI) in HaCaT cells (human keratinocyte). Cr(VI) also induced TNF-α and IL-1β mRNA expressions, through the activation of the p38 mitogen-activated protein kinase (MAPK)/MAPK-activated protein kinase 2 (MK2) pathway. Notably, the severity of the skin reactions in the epicutaneous elicitation test significantly diminished when the mouse was treated with PT. Likewise, PT intervention also ameliorated the inflammation and apoptosis of HaCaT cells in vitro. Furthermore, our current findings demonstrated that the NLRP3 inflammasome could be involved in the Cr(VI)-mediated inflammation and apoptosis of ACD. Thus, interrupting this mechanism with proper nontoxic agents, such as PT, could be a new option to improve occupational chromium toxicity and hypersensitivity.
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Zīle, Aelita. "POSSIBILITIES OF RECOVERY AND VISUALIZATION OF LATENT PAPILLAE PATTERN PRINTS FROM THE SKIN OF A DEAD PERSON. RESULTS OF A SERIES OF EXPERIMENTS." Administrative and Criminal Justice 3, no. 80 (September 30, 2017): 12. http://dx.doi.org/10.17770/acj.v3i80.2784.
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The aim of the experiment conducted by the author was to research and analyse the possibilities of leaving of latent papillae pattern prints on the skin of a dead person by natural sweat and grease substance, possibilities of transferring of them to papillae pattern prints (trace-leaving object) from other parts of the body without additional sweat and grease substance, as well as possibilities of recovery and visualization of these prints using combinations of different adhesive reagents and reagents used for their recovery. In the framework of a series of experiments 1419 latent papillae pattern prints were deposited onto the skin of 43 dead persons. 33 of them were men aged 25 to 81 years and 10 women aged 37 to 95 years. Experimental papillae pattern prints were deposited onto such parts of the body: neck, shoulders, upper arm and forearm, thigh and shin, ankles, chest, abdomen and hips. Prints were deposited by simulating the mechanism of formation of grip and pressure prints. The length of the contact was from 10 to 180 seconds. Depositing them the variable crushing force was used. After visualization and recovery of experimentally deposited latent papillae pattern prints 37 of them were recognized as valid for person identification, 66 prints contained papillae patterns, but there were not enough special features of papillae pattern to recognize them as valid for person identification. Shape of finger phalanges and palm was reflected in 202 prints, but 1114 experimentally deposited prints were not visible. The summary of the results obtained during the experiment let to conclude that the most papillae pattern prints valid for person identification were deposited onto the left and right side of the chest – 18 prints, onto the knee part of the right and the left leg – 6 prints, but onto the right and left upper arm – 3 prints. Swedish Black B-421000 and White silicone with paste hardener C-1400 (21 prints valid for person identification), Special Blower Black B-35000 and Gelatin Lifters White (FOMA) (9 prints valid for person identification), Swedish Black B-421000 and Gelatin Lifters White (FOMA) (4 prints valid for person identification were recognized as the best combinations of adhesive reagents and reagents used for recovery. The results obtained during the experiment also let to conclude that: - Microrelief of the skin (trace-perceiving object) does not always have an impact on the quality of a print; - A victim’s age and gender do not affect the quality of a print; - There is no particular proportionality between the number of deposited prints and the number of prints valid for identification.
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Nirmala, Nirmala, Vanny M. A. Tiwow, and Suherman Suherman. "Adsorpsi Ion Tembaga (Cu) Dan Ion Besi (Fe) Dengan Menggunakan Arang Hayati (Biocharcoal) Kulit Pisang Raja (Musa sapientum)." Jurnal Akademika Kimia 4, no. 4 (February 23, 2017): 189. http://dx.doi.org/10.22487/j24775185.2015.v4.i4.7870.
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This study determine the contact time, pH, and the optimum concentration of the solution ofcopper (Cu) and iron (Fe) from skin the plantain (musa sapientum). Advances in the industry todayresulted in many human activities that caused increasing impact of the pollution on surrounding of theenvironment. Environmental pollution by heavy metals being a serious problem along with increasingthe use of heavy metals in the industry. The method used in this study was a laboratory experiment usingcolorimeter. The results showed that the adsorption of copper and iron on the plantain bark influencea time variation of Cu and Fe occurred in the 60 minute and 30 minute (99.64% and 99.54%);variation of pH for Cu and Fe occurrs in pH 4 and pH 3 (99.62% and 99.58%) and variation ofconcentration for Cu and Fe occurred at 20 ppm and 1 ppm (80.74% and 96.81%), respectively.
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Bečić, F., Z. Mornjaković, I. Zulić, S. Prašović, N. Mulabegović, E. Kapić, and M. Mijanović. "Animal model of thermal injuries." Bosnian Journal of Basic Medical Sciences 3, no. 4 (November 20, 2003): 41–46. http://dx.doi.org/10.17305/bjbms.2003.3492.
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Experimental studies of burns require the use of different animal models with the aim to imitate and reproduce pathophysiological conditions. The aim of this work was to establish experimental model of thermal injury.New Zealand rabbits, weighted from 1.8 kg to 2.3 kg, were utilised during our study. Another, also utilized, animal types were laboratory Rattus rats, species Wistar, albino type, females with body weight of about 232 g. All animals were from our own litter (Institute of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine in Sarajevo). During the experiment, animal were properly situated in adequate cages and rooms, at the controlled temperature (22 ± 2°C), and in the air with normal humidity level. All animals took food and water ad libitum.Rabbits received anesthesia - intravenous pentobarbital sodium in a dose of 60 mg/kg, and then, hair from the upper side of the each rabbit ear was removed and burns were caused by a metal seal in the same manner as in rats. Rats were primarily anesthesied by intraperitoneal pentobarbital sodium in a dose of 35 mg/kg, and then, their hair was removed from the scapula zone (5 cm x 5 cm). Burns were caused by contact with a round metal seal, heated at 80°C in a water bath, during the period of 14 seconds together with contact thermometer control. Round metal seal (radius: 2.5 cm; weight: 100 g; surface: 5 cm2) was just placed on the rat skin without any additional pressure. In order to maintain the microcirculation in the burn wound and to reduce the conversion of partial-thickness skin burns to the burns of the full-thickness skin, all burn wounds were immediately sunk in the 4°C water. Subsequent to that procedure, all animals were individually situated in the proper cages, and left to rest for 4 hours with a constant cautious monitoring of the wound development and animal general state.
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Nejad, Jalil Ghassemi, Bae-Hun Lee, Ji-Yung Kim, Befekadu Chemere, Si-Chul Kim, Byong-Wan Kim, Kyu-Hyun Park, and Kyung-Il Sung. "Body Temperature Responses and Hair Cortisol Levels in Dairy Holstein Cows Fed High- and Low-Forage Diet and Under Water Deprivation During Thermal-Humidity Exposure." Annals of Animal Science 19, no. 1 (January 1, 2019): 113–25. http://dx.doi.org/10.2478/aoas-2018-0042.
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AbstractBody temperature responses and hair cortisol levels in dairy Holstein cows fed high- and low-forage diet and under water deprivation during thermal-humidity exposure (THE) were evaluated. Two experiments (Exps.) were conducted between July and September 2012 and 2013 for 64 d and 74 d, respectively. First, twenty dairy Holstein cows (90±30 DIM; 37.2±1.7 l milk/d, 620±75 kg BW) were used. The practical forage:concentrate (F:C) ratios in the low forage (LF) and high forage (HF) group were 44:56 and 56:44, respectively, while they were designed to be 40:60 and 60:40. Second, thirty dairy cows (53.5±30.4 DIM; 41.7±1.5 l milk/d,650±53 kg BW) were allotted into two groups of free access to water (FAW) and 2 h water deprivation (2hWD) following feeding. The animals were subjected to having the hair cut (1 to 2 g) from their foreheads at the same time (12:00 h) twice at the beginning (prior to the beginning of heat stress) and the end of the experiment when the cows were under THE. Hair cortisol levels (initial hair cut as the baseline and re-grown hair) were measured using ELISA method. Body temperature (BT) was measured twice daily at 7 body points of cows including rectum, vagina, hip, udder, rumen-side (flank), ear, and forehead using non-contact forehead infrared thermometer (infrared gun having two modes: inner and skin) on the 7 d of the beginning and the last 7 d of the experiment at 1000 and 1400 h. Statistical analyses were carried out using the MIXED model of SAS as repeated measurements. The intra-assay and inter-assay coefficients of variations for hair cortisol measurements were 3.15 and 10.05, respectively. Hair cortisol (HC) levels were not different within the two groups in both Exps. (P>0.05); however, HC level was lower (P<0.0001) prior to temperature-humidity exposure (THE). Results of Exp. 1 showed that vagina inner temperature was higher (P=0.041) and rectal temperature tended to be higher (P=0.083) in the HF compared to the LF group. The inner ear temperature was lower and ear skin temperature was higher (P=0.032) in the HF compared to the LF group. Forehead inner temperature was higher (P=0.048) in the LF group than in the HF group while forehead skin temperature was lower in the HF group (P=0.041). No differences were observed in the hip, udder and rumen-side (flank) temperature (both in body and skin) between the HF and LF group (P=0.012). In Exp. 2, no temperature differences were observed at all of the body points, inner and skin, between the two groups (P>0.05). However, the skin temperature in the 2hWD groups tended to be higher than in the FAW group (P=0.093). Conclusions drawn indicate the beneficial use of measuring BT at different body points of the cow in addition to RT under THE.
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Petrova, Ksenia Sergeevna, Svetlana Vladimirovna Nemirova, Maxim Georgievich Ryabkov, Artem Andreevich Karpenko, and Igor Evgenievich Pogodin. "Instrumental Non-Invasive Diagnostics of the Depth of Skin Burn: Current Opportunities and Unsolved Problems." Journal of Experimental and Clinical Surgery 14, no. 1 (January 12, 2021): 75–84. http://dx.doi.org/10.18499/2070-478x-2021-14-1-75-84.
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Introduction. Burns of various etiologies are on the 3-4 place in frequency among all injuries, they are associated with a high percentage of complications, disability and mortality. Currently, a single algorithm for objective verification of the depth of skin damage has not been developed. Numerous diagnostic technologies used to solve this problem require systemic analysis.The aim of study was to analyze current literature data on technologies for instrumental diagnostics of the depth of thermal damage to the skin.Materials and methods. A search for literary sources in databases was conducted using eLIBRARY.RU, PubMed, Cyberleninka databases. The period of publications was limited to 2011-2020.Results. The method of objective "gold standard" verification of thermal damage to the skin remains a biopsy followed by morphological examination, but the method's traumaticity does not allow it to be used for monitoring the course of the process in dynamics, for multi-focal studies. Among non-invasive methods, dermatoscopy and video microscopy are noted, but the small imaging area and the need for direct contact of the device with the skin surface limit the use of these methods. Laser Doppler flowmetry and imaging are fairly accurate non-contact methods that allow assessing the condition of a burn wound in real time. The method is not applicable to wounds with blisters, insufficient sanitation. Laser speckle contrast imaging is used to evaluate blood flow and is based on the analysis of speckle structure fluctuations. The method allows determining the degree of burn damage depending on changes in the blood flow. However, the method is difficult to apply with a vessel diameter sized 40 microns. The method is sensitive to movement and internal factors. Infrared and Raman spectroscopy are technique for evaluating vibrational patterns in a particular spectrum, these can be used to identify a molecule or determine its structure. Simultaneous use of spatial frequency visualization and speckle imaging demonstrated a high level of correlation with the results of histological research, which makes the use of these methods promising. Ultrasound also provides a proper correlation with histological data, but it is an imperfect method due to inaccuracies in determining the thickness of the epidermis, dermis, and scar condition. Optical coherence tomography (OCT) is a non-invasive optical method that allows obtaining high-resolution images of skin architecture in real time. The high level of compliance of the visualized structures, in particular, layers, appendages and vessels of the skin, with histological findings, gave this method a name "optical biopsy". Anatomical congruence of normal and damaged skin was established in an experiment between histology and OCT.Conclusion. Early assessment of the depth of thermal damage to the skin is crucial for choosing a personalized treatment strategy for the burned. None of the modern diagnostic methods is universal. Multimodal approaches to diagnostics are the most effective.
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Harbourt, David E., Andrew D. Haddow, Ashley E. Piper, Holly Bloomfield, Brian J. Kearney, David Fetterer, Kathleen Gibson, and Timothy Minogue. "Modeling the stability of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on skin, currency, and clothing." PLOS Neglected Tropical Diseases 14, no. 11 (November 9, 2020): e0008831. http://dx.doi.org/10.1371/journal.pntd.0008831.
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A new coronavirus (SARS-CoV-2) emerged in the winter of 2019 in Wuhan, China, and rapidly spread around the world. The extent and efficiency of SARS-CoV-2 pandemic is far greater than previous coronaviruses that emerged in the 21st Century. Here, we modeled stability of SARS-CoV-2 on skin, paper currency, and clothing to determine if these surfaces may factor in the fomite transmission dynamics of SARS-CoV-2. Skin, currency, and clothing samples were exposed to SARS-CoV-2 under laboratory conditions and incubated at three different temperatures (4°C± 2°C, 22°C± 2°C, and 37°C ± 2°C). We evaluated stability at 0 hours (h), 4 h, 8 h, 24 h, 72 h, 96 h, 7 days, and 14 days post-exposure. SARS-CoV-2 was stable on skin through the duration of the experiment at 4°C (14 days). Virus remained stable on skin for at least 96 h at 22°C and for at least 8h at 37°C. There were minimal differences between the tested currency samples. The virus remained stable on the $1 U.S.A. Bank Note for at least 96 h at 4°C while we did not detect viable virus on the $20 U.S.A. Bank Note samples beyond 72 h. The virus remained stable on both Bank Notes for at least 8 h at 22°C and 4 h at 37°C. Clothing samples were similar in stability to the currency. Viable virus remained for at least 96 h at 4°C and at least 4 h at 22°C. We did not detect viable virus on clothing samples at 37°C after initial exposure. This study confirms the inverse relationship between virus stability and temperature. Furthermore, virus stability on skin demonstrates the need for continued hand hygiene practices to minimize fomite transmission both in the general population as well as in workplaces where close contact is common.
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Tanasie, Gabriela, Florina Bojin, Romulus Fabian Tatu, Alina Maria Sisu, Mirabela Cristea, Daniela Anca Puscasiu, Emanuel Adelin Nemes, and Carmen Sofica Tatu. "In Vitro Effects of Biomaterials on Mesenchymal Stem Cells Viability and Proliferation." Materiale Plastice 54, no. 3 (September 30, 2017): 523–26. http://dx.doi.org/10.37358/mp.17.3.4886.
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Mesenchymal stem cells (MSCs) are increasingly being used in regenerative medicine to repair various tissue types. This study aimed to assess changes in MSCs properties as a result of their interaction with two biomaterials in order to evaluate their in vitro compatibility. We have used two types of biomaterials, as follows: hydroxyapatite anodized titanium (HA-Ti) is used in bone reconstruction; it is hard and remains in the body, while patches of collagen combined with poly-e-caprolactone (C-PCL) are utilized in the reconstruction of soft tissue (particularly the skin); these patches resorb in the body, being only a temporary matrix that fosters and accelerates tissue formation. We have chosen to assess changes in morphology, viability and proliferation of MSCs obtained by lipoaspirate, through direct contact with the biomaterial or in eluate. MSCs properties were assessed by optical microscopy, fluorescence microscopy after acridine orange/ethidium bromide (AO/EB) staining, and the MTT assay. After result interpretation, we gained an image of the cytotoxicity phenomenon seen during the experiment and were able to assess viability of cell in contact with the biomaterials used. HA-Ti shows better interaction with cells, which preserve their viability, and does not influence MSCs growth, proliferation or morphology. In contrast, cells on C-PCL matrix become small, spherical, were detached from the plate and had lower viability percentage.
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Matsinovich, M. "Food allergies in weaned piglets in experiment and spontaneous occurrence." Naukovij vìsnik veterinarnoï medicini, no. 2 (144) (December 24, 2018): 81–86. http://dx.doi.org/10.33245/2310-4902-2018-144-2-81-86.
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Gastrointestinal diseases in young animals are recorded quite often, especially in industrial complexes. Diseases of this group can be up to 70-80 % of the entire internal pathology of young animals. Literary data show that in the etiology and pathogenesis of the disease in weaned piglets an allergic reaction to the components of the feed, which significantly complicates its course, may play. The development of nutritional allergies is also favored by the functional insufficiency of the glands of the digestive system of pigs during the first weeks of life, as well as the violation of their functions in various diseases of the gastrointestinal tract, which can lead to incomplete protein breakdown and accumulation of antigenic substances. The aim of the study was to study the most characteristic symptoms and blood indices during experimental reproduction of food allergies in piglets and spontaneous occurrence under production conditions. Studies were performed in 2 stages. At first, under the conditions of the clinic of the Department of Internal noninfectious Animal Diseases of the Vitebsk State Academy of Veterinary Medicine formed two groups of pigs aged 30–35 days with an average weight of 8–10 kg. In animals of the experimental group, experimental reproduction of feed allergies was carried out by abruptly changing the milk type of feeding to the concentrated one. At the second stage of the research, in the conditions of a pig complex, 200 pigs of 40- to 60-day-old patients with gastroenteritis were examined. Gastroenteritis in experimental animals was non-infectious in nature and was primarily due to the sharp weaning of animals. To detect an allergic reaction, laboratory blood tests were performed using the above methods, and also the clinical manifestations of the disease were taken into account. The clinical picture of experimental pathology at first was characterized by lethargy, reluctant eating of new food, the pigs periodically showed anxiety, which was followed by apathy. During the first three days of the experiment, intestinal meteorism was observed in piglets, which in 6 animals and 66,7 % was replaced by diarrhea, and in 33.3 % animals it was accompanied by constipation. Body temperature in all porosyat remained within the normal range. On the fourth day of the experiment, one of the animals of the experimental group fell, and according to the results of the autopsy, catarrhal-hemorrhagic were found: pa-strorenteritis, typhlitis and colitis. By the twelfth day, the functions of the gastrointestinal tract were normalized in all animals of the experimental group. In the animals of the control group during clinical observation for this period, no abnormalities were identified. On the 14th day of the experiment, an intracutaneous test was performed. As an allergen, we used a protein extract from the feed used in the experiment, containing the gliadin, albumin and globulin fractions of the gluten protein. In all the animals of the experimental group, after 6 hours, edema of the skin and hyperemia appeared at the injection site, the skin fold thickness was from 1,5 to 2,5 mm at the injection site of the allergen, compared with 0,5-0,7 mm in injection site phosphate buffer. 24 hours after the injection of the allergen, the intensity of skin hyperemia decreased, but there was a noticeable thickening of the skin fold in the animals of the experimental group, it was 3,6 ± 0,22 mm compared to 0.6 ± 0.04 mm at the injection site of phosphate buffer. Changes in the skin at the injection site disappeared within 24 to 48 hours. The results of laboratory blood tests indicate the development of an allergic reaction in animals of the experimental group. They were characterized by more pronounced leukocytosis and eosinophilia, as well as a higher concentration of total protein in the blood serum, of immunoglobulins at 14-21 days, i.e. during the period of the greatest severity of the allergic reaction. The most significant and statistically significant in such animals was a more than 2-fold increase in the number of eosinophils and an increase in the concentration of immunoglobulins by 21 %. A significant concentration of circulating immune complexes of the CIC was detected in the blood of the piglets of the experimental group, as evidenced by a lower % of light transmission in a special test – below 95 %. In the experiment in the conditions of the pig complex, it was found that in 27 % of weaned piglets in the pathogenesis of gastroenteritis, sensibilization of the body develops and the allergic factor affects the duration and severity of the disease. The duration of the disease (with treatment without antihistamine drugs) was 5 –10 days (6,8 ± 0,32 days) with a mortality rate of 4.4 %. More than 30 % of the pigs during the first 7 to 14 days after weaning and recovery observed the recurrence of the disease for no apparent reason. Thus, an unusual new feed load, in the period of extraction, leads to the depletion of the local protection mechanisms of the gastrointestinal tract in piglets. In the mucous membrane of the small intestine, inflammation develops, which leads to a violation of the secretory, enzymatic, absorbing function of the intestine and metabolic disorder. Against this background, feed antigens come from the intestine into the blood and as a result of their contact with immunocompetent cells, an immune response and body sensitization develops. Experimental and spontaneous feed allergies in weaned piglets are similar in clinical laboratory to laboratory. In terms of production, the weaned piglets of patients with gastroenteritis developed an allergic reaction as a complication of the disease, while the duration of the disease and mortality was almost 2 times greater. Key words: food allergies, gastroenteritis, piglets, weaning, therapeutic efficacy, circulating immune complexes.
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Shagrov, L. L., N. A. Shutsky, S. L. Kashutin, Valentin I. Nikolaev, and S. I. Malyavskaya. "On the participation of eosinophils in tissue recovery after a local cold injury." HERALD of North-Western State Medical University named after I.I. Mechnikov 12, no. 2 (August 21, 2020): 71–78. http://dx.doi.org/10.17816/mechnikov202012271-78.
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The article studies the correlation of the content of peripheral blood and red bone marrow eosinophils with the level of secretion of fibroblast growth factor (FGF-21), insulin-like factor (IGF-1) and vasculoendothelial growth factor (VEGF-C) in blood serum during the formation of dermal collagen after local cold damage. Animals of the experimental group after the onset of narcotic sleep on the depilated skin of the back were simulated contact frostbite of the 3rd degree. On the 3rd, 7th, 14th and 21st day of the experiment, the concentrations of growth factors, % dermal collagen content, and also the content of eosinophils in peripheral blood and red bone marrow were determined in the blood serum. The research results showed that the development of eosinopenia after a local cold injury occurs due to the sequestration of eosinophils in the affected area. The presence of reactive changes after a local cold injury not only in peripheral blood, but also in the red bone marrow may indicate the participation of eosinophils in tissue repair processes after a local cold injury.
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Kawakami, Atsushi, Katsumi Eguchi, Hiroaki Ida, Yojiro Kawabe, Takaaki Fukuda, Tadayuki Ishimaru, Kenichi Kurouji, et al. "Endothelial cells stimulate proliferation of human thyroid epithelial cells." Acta Endocrinologica 125, no. 2 (August 1991): 212–18. http://dx.doi.org/10.1530/acta.0.1250212.
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Abstract. The present study was undertaken to investigate cellular interactions between human thyroid epithelial cells (thyrocytes) and endothelial cells. Normal thyrocytes were cultured with either mitomycin C-treated endothelial cells or mitomycin C-treated human foreskin fibroblasts. The proliferative responses of thyrocytes were markedly stimulated by endothelial cells, but not by skin fibroblasts. The proliferative response of the thyrocytes obtained from patients with Graves' disease were similar to that of normal thyrocytes. Furthermore, the cell number of thyrocytes in endothelial cell-thyrocyte co-culture was markedly increased as compared with that in thyrocytes alone. The culture medium of endothelial cells only partly had any effect in the endothelial cell-thyrocyte co-culture experiment. Indomethacin, a cyclooxygenase inhibitor, did not increase the endothelial cells-induced thyrocyte proliferation. Furthermore, the increased proliferative response of thyrocytes stimulated by endothelial cells was not suppressed by heparin. These results suggest that endothelial cells increase thyrocyte proliferation, and that cell contact or extracellular matrix production by endothelial cells may play an important role in the proliferation of thyrocytes.
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Jirkovec, Radek, Alzbeta Samkova, Tomas Kalous, Jiri Chaloupek, and Jiri Chvojka. "Preparation of a Hydrogel Nanofiber Wound Dressing." Nanomaterials 11, no. 9 (August 25, 2021): 2178. http://dx.doi.org/10.3390/nano11092178.
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The study addressed the production of a hydrogel nanofiber skin cover and included the fabrication of hydrogel nanofibers from a blend of polyvinyl alcohol and alginate. The resulting fibrous layer was then crosslinked with glutaraldehyde, and, after 4 h of crosslinking, although the gelling component, i.e., the alginate, crosslinked, the polyvinyl alcohol failed to do so. The experiment included the comparison of the strength and ductility of the layers before and after crosslinking. It was determined that the fibrous layer following crosslinking evinced enhanced mechanical properties, which acted to facilitate the handling of the material during its application. The subsequent testing procedure proved that the fibrous layer was not cytotoxic. The study further led to the production of a modified hydrogel nanofiber layer that combined polyvinyl alcohol with alginate and albumin. The investigation of the fibrous layers produced determined that following contact with water the polyvinyl alcohol dissolved leading to the release of the albumin accompanied by the swelling of the alginate and the formation of a hydrogel.
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Kulikauskaitė, Dovilė, and Dainius Paliulis. "FORMALDEHYDE REMOVAL FROM WASTEWATER APPLYING NATURAL ZEOLITE / FORMALDEHIDO ŠALINIMAS IŠ NUOTEKŲ PANAUDOJANT GAMTINĮ CEOLITĄ." Mokslas – Lietuvos ateitis 7, no. 4 (September 29, 2015): 443–48. http://dx.doi.org/10.3846/mla.2015.808.
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Formaldehyde is one of the most chemically active compounds which is discharged with untreated or just partially treated industrial wastewater. It is hazardous for environment and humans. Formaldehyde vapors can strongly irritate skin, can cause damage to eyes and harm respiratory tract. As long as formaldehyde causes a toxic effect on environment and living organisms, it is necessary to remove it from wastewater which is directed to natural water. There are many methods used for formaldehyde removal from wastewater: biological method, evaporation, membrane separation method. Most of them have disadvantages. Adsorption method has many advantages: it is fast, cheap, and universal, and can be widely used, therefore it was chosen for this research. Experiment was carried out with natural zeolite in different contact time with different concentration formaldehyde solutions. Concentration of formaldehyde was determined applying the Photocolorimetric Method. Method is based on reaction of formaldehyde with chromotropic acid and determination of formaldehyde concentration. Determined average sorption efficiency was highest when formaldehyde concentration was lowest, e. g. 2 mg/l (45.94%) after eight hours of contact time with adsorbent. Sorption efficiency was increasing when the contact time increased, but when the contact time increased to 12 hours, sorption efficiency stayed the same because of the saturation of zeolite. Formaldehidas yra vienas iš aktyviausių junginių, kuris išleidžiamas į aplinką kartu su nevalytomis ar iš dalies išvalytomis gamybinėmis nuotekomis. Jis yra pavojingas tiek aplinkai, tiek žmonėms. Formaldehido garai stipriai dirgina akis ir kvėpavimo sistemą. Kadangi formaldehidas yra pavojingas žmonėms ir visiems gyviems organizmams, jis turi būti šalinamas iš gamybinių nuotekų. Sorbcijos metodas turi daug privalumų: jis yra greitas, pigus ir universalus, todėl vienas iš labiausiai perspektyvių vandens valymo metodų – sorbcija. Tai pagrindinė priežastis, kodėl sorbcinis metodas buvo pasirinktas eksperimentiniams tyrimams. Eksperimentiniai tyrimai buvo atlikti naudojat gamtinį ceolitą, buvo parinktas skirtingas formaldehido tirpalo kontakto laikas su adsorbentu ir matuojama teršalų koncentracija po kontakto su adsorbentu. Šis metodas yra paremtas formaldehido reakcija su chromotropine rūgštimi. Sorbcijos efektyvumas augo ilgėjant kontakto su ceolitu laikui, tačiau po 12 valandų efektyvumas nebedidėjo dėl to, kad sorbentas įsisotino.
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Thomson, Neroli A., David G. Thomas, Karin Weidgraaf, and John S. Munday. "Felis catus papillomavirus type 2 DNA loads on kittens are transient and do not reflect their susceptibility to infection." Journal of Feline Medicine and Surgery 20, no. 4 (May 26, 2017): 332–38. http://dx.doi.org/10.1177/1098612x17710382.
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Objectives Felis catus papillomavirus type 2 (FcaPV-2) commonly infects the skin of domestic cats, and mounting evidence suggests that the virus could be involved in a subset of feline skin cancers. The reason why some cats develop FcaPV-2-induced disease and others do not is currently unknown. However, it has been shown that kittens in different litters have markedly different FcaPV-2 DNA loads and the aim of this study was to determine whether these differences could be due to inherent differences in susceptibility to infection. Such differences could potentially explain why only a small proportion of cats develop FcaPV-2-associated skin disease. Methods Repeated skin swabs were taken to measure FcaPV-2 DNA loads in queens and kittens in a research colony. The kittens either stayed in their original litters or were moved between litters; eventually, all of the kittens were housed together. A subset of samples was also analysed for FcaPV-2 mRNA. Results While there were initially large differences in FcaPV-2 DNA loads between litters of kittens, these differences disappeared when the kittens were moved between litters or housed together. Importantly, the viral DNA loads changed too rapidly to be due to the acquisition or clearance of infection. In contrast, the differences in viral DNA loads between the different queens were sustained throughout the experiment. FcaPV-2 mRNA was also detected in samples from 1- to 8-day-old kittens. Conclusions and relevance The results suggest that the FcaPV-2 DNA load in a swab sample from an individual kitten largely reflects the overall level of FcaPV-2 shedding in the group of in-contact cats, rather than the infection status of the individual kitten. Therefore, there was no evidence for inherent differences in susceptibility to infection. However, the finding of FcaPV-2 mRNA suggests that at least some kittens do become infected with FcaPV-2 early in life.
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Strigo, Irina A., Franco Carli, and M. Catherine Bushnell. "Effect of Ambient Temperature on Human Pain and Temperature Perception." Anesthesiology 92, no. 3 (March 1, 2000): 699–707. http://dx.doi.org/10.1097/00000542-200003000-00014.
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Background Animal studies show reduced nociceptive responses to noxious heat stimuli and increases in endogenous beta-endorphin levels in cold environments, suggesting that human pain perception may be dependent on ambient temperature. However, studies of changes in local skin temperature on human pain perception have yielded variable results. This study examines the effect of both warm and cool ambient temperature on the perception of noxious and innocuous mechanical and thermal stimuli. Methods Ten subjects (7 men and 3 women, aged 20-23 yr) used visual analog scales to rate the stimulus intensity, pain intensity, and unpleasantness of thermal (0-50 degrees C) and mechanical (1.2-28.9 g) stimuli applied on the volar forearm with a 1-cm2 contact thermode and von Frey filaments, respectively. Mean skin temperatures were measured throughout the experiment by infrared pyrometer. Each subject was tested in ambient temperatures of 15 degrees C (cool), 25 degrees C (neutral), and 35 degrees C (warm) on separate days, after a 30-min acclimation to the environment. Studies began in the morning after an 8-h fast. Results Mean skin temperature was altered by ambient temperature (cool room: 30.1 degrees C; neutral room: 33.4 degrees C; warm room: 34.5 degrees C; P < 0.0001). Ambient temperature affected both heat (44-50 degrees C) and cold (25-0 degrees C) perception (P < 0.01). Stimulus intensity ratings tended to be lower in the cool than in the neutral environment (P < 0.07) but were not different between the neutral and warm environments. Unpleasantness ratings revealed that cold stimuli were more unpleasant than hot stimuli in the cool room and that noxious heat stimuli were more unpleasant in a warm environment. Environmental temperature did not alter ratings of warm (37 and 40 degrees C) or mechanical stimuli. Conclusions These results indicate that, in humans, a decrease in skin temperature following exposure to cool environments reduces thermal pain. Suppression of Adelta primary afferent cold fiber activity has been shown to increase cold pain produced by skin cooling. Our current findings may represent the reverse phenomenon, i.e., a reduction in thermal nociceptive transmission by the activation of Adelta cutaneous cold fibers.
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Miljkovic, B., Z. Skrbic, Z. Pavlovski, M. Lukic, V. Ivetic, B. Kureljusic, and V. Petricevic. "Foot-pad dermatitis in commercial broilers." Biotehnologija u stocarstvu 28, no. 4 (2012): 835–43. http://dx.doi.org/10.2298/bah1204835m.
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In the present experiment, the presence of mycological agents in chickens with skin lesions on foot pads was investigated, in order to improve the health of broiler chickens. Foot-pad dermatitis (FPD) is described in the literature as dermatitis caused by multifactor causes. The presence of irritating chemical substances in the litter, genetic predispositions of hybrids, immune suppressive diseases of chickens, as well as the composition of commercial broiler diets that influence the occurrence of wet litter, are proven factors that contribute to a more intensive incidence of foot-pad dermatitis. Foot-pad dermatitis is a condition characterized by lesions on metatarsal and digital ventral skin of poultry feet. It is type of contact dermatitis which in severe cases shows slower weight gain, poor health condition and welfare. Taking into consideration the literature data, chickens reared in closed facilities where the bacterial and mycological agents are present partly in the litter if not properly disinfected, but also in the food or the chicken plumage, we wanted to investigate their presence in the skin of foot pads. The study was focused on incidence of foot-pad dermatitis in 500 one day old broiler chickens of Hubbard genotype, in two feeding (standard/economical) programs for broilers available on our market. Chopped straw was used as litter. At the end of fattening, all chickens were examined for the presence of lesions on the skin of the feet. Total of 39 chickens were allocated to the intensity of the lesion on foot pads rated as 2 (mild) and 3 (severe). In the mycological examination of the 9 samples of autoclaved chicken legs with lesions on the feet, we have isolated and identified the presence of fungi /mould Aspergillus fumigatus. The histopathology investigation, during which the tissue section from mild and severe skin foot pads was collected and stained using Hematoxylin and eosin, revealed the hyperkeratosis, panniculitis, ballooning degeneration and dermis inflammation. No fungal elements were observed in the sections of pads stained with Gomori methenamine silver. Birds are especially susceptible to infection with Aspergillus fumigatus. That species of fungus is also classified as allergenic factor.
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Bečić, Fahir, Nedžad Mulabegović, Zakira Mornjaković, Elvedina Kapić, Senad Prašović, Ervina Bečić, and Jasna Kusturica. "Topical treatment of standardised burns with herbal remedies in model rats." Bosnian Journal of Basic Medical Sciences 5, no. 4 (November 20, 2005): 50–57. http://dx.doi.org/10.17305/bjbms.2005.3233.
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Experimental studies of burns require the use of different animal models. The aim of this work was to establish experimental model of thermal injuries and to evaluate the effects of topical agents on healing of the burn wounds. Forty female Wistar rats were randomly classified in 4 groups and isolated for 2 weeks before the onset of experiment. Animals were primarily anaesthetized with pentobarbital-sodium and then shaved (skin area of their back with diameters 5 cm x 5 cm). A round metal stamp with contact area of 5 cm2 and total weight of 100 g was heated up to 80°C and then applied without additional pressure on the depilated skin of the back for 14 seconds. This procedure produced a standardized burn wound. Induced burn wounds were immediately drowned in the 4°C-water for 3 s in order to maintain microcirculation. After the inducement of thermal injures, all rats were treated with 1% silver sulfadiazine cream, herbal topical preparations or were not treated at all. Burn wounds were treated twice a day until the healing completion. The result of treatment application was a significant reduction of burn wound diameters. Herbal topical preparations expressed positive therapeutic effects on the parameters of burn wounds. The efficiency of silver sulfadiazine cream in burn wound healing was significantly more expressed in comparison to healing process in control group of animals (p<0,001). We conclude that herbal topical preparations efficiently caused the completion of burn wound healing process without scar formation.
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Surikova, Ekaterina I., Elena M. Frantsiyants, Irina V. Kaplieva, Valeria A. Bandovkina, Lidia K. Trepitaki, Irina V. Neskubina, Inga Movlievna Kotieva, Konstantin A. Shumarin, and Galina V. Zhukova. "Suppression of tumor development by another tumor in primary immunodeficiency in experiment." Journal of Clinical Oncology 39, no. 15_suppl (May 20, 2021): e21583-e21583. http://dx.doi.org/10.1200/jco.2021.39.15_suppl.e21583.
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e21583 Background: Multiple primary malignant tumors (MPMTs) are characterized by the presence of several primary neoplasms in one patient. The purpose of the study was to create an experimental model of MPMTs with one dominating tumor. Methods: The study included 21 female BALB/c Nude mice. The main group included mice with simultaneous subcutaneous inoculation of tumors: Guerin's carcinoma (0.5 million tumor cells in 0.5 ml of saline solution) under the right scapula and B16/F10 melanoma (0.5 ml of suspension diluted 1:20 in saline solution) under the left scapula. Control groups included females with melanoma or carcinoma inoculated at the same dosage and volume as in the main group. Results: In a MPMT model, tumors appeared 3 times faster than in controls and demonstrated larger volumes: melanoma – by 7.5 times, carcinoma – by 2.2 times; the survival of mice with MPMTs decreased. Carcinoma in a MPMT model metastasized to melanoma and almost completely suppressed its growth. Melanoma was represented by a small “island” of tumor tissue 3-4 mm in diameter and was located just under the skin at the site of injection of melanoma cells. The light part of the same loose pasty consistency as the dark part, with a diameter of 6-7 mm, was located around the dark “center” of melanoma. The rest part of the tumor located under the left scapula looked like an elongated grayish-pink node of a dense elastic consistency - just like the tumor located under the right scapula, which was much larger in volume. The right and left tumors did not merge with each other; there was a small distance of about 2-3 mm between them. A small lesion of caseous necrosis, 6–7 mm in diameter, was recorded in the center of the right tumor node of Guerin's carcinoma; there was no necrosis in the left tumor. Smaller size, the absence of necrosis and visually more “young” carcinoma tissue on the left indicated its later appearance than that on the right, which, in combination with the remnants of melanoma fused to the left tumor and the absence of “contact” between the left tumor and the right one, indicated the metastatic nature of Guerin’s carcinoma on the left. B16/F10 melanoma did not metastasize. Conclusions: In simultaneous subcutaneous inoculation of murine B16/F10 melanoma and rat Guerin’s carcinoma to female BALB/c Nude mice, carcinoma cells metastasized to melanoma and suppressed its growth.