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Sample records for high bite forces

  1. Bite Forces and Their Measurement in Dogs and Cats

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    Se Eun Kim

    2018-04-01

    Full Text Available Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs, and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull’s morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

  2. Bite Forces and Their Measurement in Dogs and Cats.

    Science.gov (United States)

    Kim, Se Eun; Arzi, Boaz; Garcia, Tanya C; Verstraete, Frank J M

    2018-01-01

    Bite force is generated by the interaction of the masticatory muscles, the mandibles and maxillae, the temporomandibular joints (TMJs), and the teeth. Several methods to measure bite forces in dogs and cats have been described. Direct in vivo measurement of a bite in dogs has been done; however, bite forces were highly variable due to animal volition, situation, or specific measurement technique. Bite force has been measured in vivo from anesthetized dogs by electrical stimulation of jaw adductor muscles, but this may not be reflective of volitional bite force during natural activity. In vitro bite forces have been estimated by calculation of the force produced using mechanical equations representing the jaw adductor muscles and of the mandible and skull structure Bite force can be estimated in silico using finite element analysis (FEA) of the computed model of the anatomical structures. FEA can estimate bite force in extinct species; however, estimates may be lower than the measurements in live animals and would have to be validated specifically in domestic dogs and cats to be reliable. The main factors affecting the bite forces in dogs and cats are body weight and the skull's morphology and size. Other factors such as oral pain, TMJ disorders, masticatory muscle atrophy, and malocclusion may also affect bite force. Knowledge of bite forces in dogs and cats is essential for various clinical and research fields such as the development of implants, materials, and surgical techniques as well as for forensic medicine. This paper is a summary of current knowledge of bite forces in dogs and cats, including the effect of measurement methods and of other factors.

  3. Measurement of dynamic bite force during mastication.

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    Shimada, A; Yamabe, Y; Torisu, T; Baad-Hansen, L; Murata, H; Svensson, P

    2012-05-01

    Efficient mastication of different types and size of food depends on fast integration of sensory information from mechanoreceptors and central control mechanisms of jaw movements and applied bite force. The neural basis underlying mastication has been studied for decades but little progress in understanding the dynamics of bite force has been made mainly due to technical limitations of bite force recorders. The aims of this study were to develop a new intraoral bite force recorder which would allow the study of natural mastication without an increase in the occlusal vertical dimension and subsequently to analyze the relation between electromyographic (EMG) activity of jaw-closing muscles, jaw movements and bite force during mastication of five different types of food. Customized force recorders based on strain gauge sensors were fitted to the upper and lower molar teeth on the preferred chewing side in fourteen healthy and dentate subjects (21-39 years), and recordings were carried out during voluntary mastication of five different kinds of food. Intraoral force recordings were successively obtained from all subjects. anova showed that impulse of bite force as well as integrated EMG was significantly influenced by food (Pmastication with direct implications for oral rehabilitation. We also propose that the control of bite force during mastication is achieved by anticipatory adjustment and encoding of bolus characteristics. © 2012 Blackwell Publishing Ltd.

  4. The relationship between oral tori and bite force.

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    Jeong, Chan-Woo; Kim, Kyung-Ho; Jang, Hyo-Won; Kim, Hye-Sun; Huh, Jong-Ki

    2018-01-12

    Objective The relationship between bite force and torus palatinus or mandibularis remains to be explained. The major aim of this study was to determine the correlation between bite force and oral tori. Methods The bite force of 345 patients was measured with a bite force recorder; impressions of the shape and size of the oral tori were taken on plaster models prior to orthodontic treatments. Subsequently, the relationship between oral tori and bite force was analyzed. Results The size, shape, and incidence of torus palatinus was not significantly correlated with bite force. However, the size of torus mandibularis increased significantly in proportion to the bite force (p = 0.020). The occurrence of different types of oral tori was not correlated with the bite force. Discussion The size of torus mandibularis provides information about bite force and can thus be used to clinically assess occlusal stress.

  5. Feeding biomechanics and theoretical calculations of bite force in bull sharks (Carcharhinus leucas) during ontogeny.

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    Habegger, Maria L; Motta, Philip J; Huber, Daniel R; Dean, Mason N

    2012-12-01

    Evaluations of bite force, either measured directly or calculated theoretically, have been used to investigate the maximum feeding performance of a wide variety of vertebrates. However, bite force studies of fishes have focused primarily on small species due to the intractable nature of large apex predators. More massive muscles can generate higher forces and many of these fishes attain immense sizes; it is unclear how much of their biting performance is driven purely by dramatic ontogenetic increases in body size versus size-specific selection for enhanced feeding performance. In this study, we investigated biting performance and feeding biomechanics of immature and mature individuals from an ontogenetic series of an apex predator, the bull shark, Carcharhinus leucas (73-285cm total length). Theoretical bite force ranged from 36 to 2128N at the most anterior bite point, and 170 to 5914N at the most posterior bite point over the ontogenetic series. Scaling patterns differed among the two age groups investigated; immature bull shark bite force scaled with positive allometry, whereas adult bite force scaled isometrically. When the bite force of C. leucas was compared to those of 12 other cartilaginous fishes, bull sharks presented the highest mass-specific bite force, greater than that of the white shark or the great hammerhead shark. A phylogenetic independent contrast analysis of anatomical and dietary variables as determinants of bite force in these 13 species indicated that the evolution of large adult bite forces in cartilaginous fishes is linked predominantly to the evolution of large body size. Multiple regressions based on mass-specific standardized contrasts suggest that the evolution of high bite forces in Chondrichthyes is further correlated with hypertrophication of the jaw adductors, increased leverage for anterior biting, and widening of the head. Lastly, we discuss the ecological significance of positive allometry in bite force as a possible

  6. Reliable quantification of bite-force performance requires use of appropriate biting substrate and standardization of bite out-lever.

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    Lappin, A Kristopher; Jones, Marc E H

    2014-12-15

    Bite-force performance is an ecologically important measure of whole-organism performance that shapes dietary breadth and feeding strategies and, in some taxa, determines reproductive success. It also is a metric that is crucial to testing and evaluating biomechanical models. We reviewed nearly 100 published studies of a range of taxa that incorporate direct in vivo measurements of bite force. Problematically, methods of data collection and processing vary considerably among studies. In particular, there is little consensus on the appropriate substrate to use on the biting surface of force transducers. In addition, the bite out-lever, defined as the distance from the fulcrum (i.e. jaw joint) to the position along the jawline at which the jaws engage the transducer, is rarely taken into account. We examined the effect of bite substrate and bite out-lever on bite-force estimates in a diverse sample of lizards. Results indicate that both variables have a significant impact on the accuracy of measurements. Maximum bite force is significantly greater using leather as the biting substrate compared with a metal substrate. Less-forceful bites on metal are likely due to inhibitory feedback from mechanoreceptors that prevent damage to the feeding apparatus. Standardization of bite out-lever affected which trial produced maximum performance for a given individual. Indeed, maximum bite force is usually underestimated without standardization because it is expected to be greatest at the minimum out-lever (i.e. back of the jaws), which in studies is rarely targeted with success. We assert that future studies should use a pliable substrate, such as leather, and use appropriate standardization for bite out-lever. © 2014. Published by The Company of Biologists Ltd.

  7. Effects of bruxism on the maximum bite force

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    Todić Jelena T.

    2017-01-01

    Full Text Available Background/Aim. Bruxism is a parafunctional activity of the masticatory system, which is characterized by clenching or grinding of teeth. The purpose of this study was to determine whether the presence of bruxism has impact on maximum bite force, with particular reference to the potential impact of gender on bite force values. Methods. This study included two groups of subjects: without and with bruxism. The presence of bruxism in the subjects was registered using a specific clinical questionnaire on bruxism and physical examination. The subjects from both groups were submitted to the procedure of measuring the maximum bite pressure and occlusal contact area using a single-sheet pressure-sensitive films (Fuji Prescale MS and HS Film. Maximal bite force was obtained by multiplying maximal bite pressure and occlusal contact area values. Results. The average values of maximal bite force were significantly higher in the subjects with bruxism compared to those without bruxism (p 0.01. Maximal bite force was significantly higher in the males compared to the females in all segments of the research. Conclusion. The presence of bruxism influences the increase in the maximum bite force as shown in this study. Gender is a significant determinant of bite force. Registration of maximum bite force can be used in diagnosing and analysing pathophysiological events during bruxism.

  8. Bite force measurement based on fiber Bragg grating sensor

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    Padma, Srivani; Umesh, Sharath; Asokan, Sundarrajan; Srinivas, Talabattula

    2017-10-01

    The maximum level of voluntary bite force, which results from the combined action of muscle of mastication, joints, and teeth, i.e., craniomandibular structure, is considered as one of the major indicators for the functional state of the masticatory system. Measurement of voluntary bite force provides useful data for the jaw muscle function and activity along with assessment of prosthetics. This study proposes an in vivo methodology for the dynamic measurement of bite force employing a fiber Bragg grating (FBG) sensor known as bite force measurement device (BFMD). The BFMD developed is a noninvasive intraoral device, which transduces the bite force exerted at the occlusal surface into strain variations on a metal plate. These strain variations are acquired by the FBG sensor bonded over it. The BFMD developed facilitates adjustment of the distance between the biting platform, which is essential to capture the maximum voluntary bite force at three different positions of teeth, namely incisor, premolar, and molar sites. The clinically relevant bite forces are measured at incisor, molar, and premolar position and have been compared against each other. Furthermore, the bite forces measured with all subjects are segregated according to gender and also compared against each other.

  9. Bite force and occlusal stress production in hominin evolution.

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    Eng, Carolyn M; Lieberman, Daniel E; Zink, Katherine D; Peters, Michael A

    2013-08-01

    Maximum bite force affects craniofacial morphology and an organism's ability to break down foods with different material properties. Humans are generally believed to produce low bite forces and spend less time chewing compared with other apes because advances in mechanical and thermal food processing techniques alter food material properties in such a way as to reduce overall masticatory effort. However, when hominins began regularly consuming mechanically processed or cooked diets is not known. Here, we apply a model for estimating maximum bite forces and stresses at the second molar in modern human, nonhuman primate, and hominin skulls that incorporates skeletal data along with species-specific estimates of jaw muscle architecture. The model, which reliably estimates bite forces, shows a significant relationship between second molar bite force and second molar area across species but does not confirm our hypothesis of isometry. Specimens in the genus Homo fall below the regression line describing the relationship between bite force and molar area for nonhuman anthropoids and australopiths. These results suggest that Homo species generate maximum bite forces below those predicted based on scaling among australopiths and nonhuman primates. Because this decline occurred before evidence for cooking, we hypothesize that selection for lower bite force production was likely made possible by an increased reliance on nonthermal food processing. However, given substantial variability among in vivo bite force magnitudes measured in humans, environmental effects, especially variations in food mechanical properties, may also be a factor. The results also suggest that australopiths had ape-like bite force capabilities. Copyright © 2013 Wiley Periodicals, Inc.

  10. Influence of maximum bite force on jaw movement during gummy jelly mastication.

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    Kuninori, T; Tomonari, H; Uehara, S; Kitashima, F; Yagi, T; Miyawaki, S

    2014-05-01

    It is known that maximum bite force has various influences on chewing function; however, there have not been studies in which the relationships between maximum bite force and masticatory jaw movement have been clarified. The aim of this study was to investigate the effect of maximum bite force on masticatory jaw movement in subjects with normal occlusion. Thirty young adults (22 men and 8 women; mean age, 22.6 years) with good occlusion were divided into two groups based on whether they had a relatively high or low maximum bite force according to the median. The maximum bite force was determined according to the Dental Prescale System using pressure-sensitive sheets. Jaw movement during mastication of hard gummy jelly (each 5.5 g) on the preferred chewing side was recorded using a six degrees of freedom jaw movement recording system. The motion of the lower incisal point of the mandible was computed, and the mean values of 10 cycles (cycles 2-11) were calculated. A masticatory performance test was conducted using gummy jelly. Subjects with a lower maximum bite force showed increased maximum lateral amplitude, closing distance, width and closing angle; wider masticatory jaw movement; and significantly lower masticatory performance. However, no differences in the maximum vertical or maximum anteroposterior amplitudes were observed between the groups. Although other factors, such as individual morphology, may influence masticatory jaw movement, our results suggest that subjects with a lower maximum bite force show increased lateral jaw motion during mastication. © 2014 John Wiley & Sons Ltd.

  11. Three-dimensional analyses of human bite-force magnitude and moment.

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    van Eijden, T M

    1991-01-01

    The effect of the three-dimensional orientation of occlusal force on maximal bite-force magnitude was examined in seven human subjects at three different unilateral anteroposterior bite positions (canine, second premolar and second molar). At each position, bite-force magnitude was registered in 17 precisely defined directions using a three-component force transducer and a feedback method. In addition, to assess the efficiency of transfer of muscle to bite force, for bites produced in the sagittal plane, moment-arm length was determined and the produced bite-force moment calculated. The results showed that the largest possible bite force was not always produced in a direction perpendicular to the occlusal plane. Generally, maximal bite force in medial and posterior directions was larger than that in, respectively, corresponding lateral and anterior directions. In each direction the produced force was larger at the posterior bite point than at the anterior bite point. The combined moment produced by the jaw muscles was largest for vertical bites, smallest for posteriorly directed bites and intermediate for anteriorly directed bites. In the case of vertically and anteriorly directed bites the produced moment did not vary significantly with the bite position. Hence, for these bite positions the jaw closing moment of the muscles must have kept constant. In the case of posteriorly directed bites the produced moment decreased when bite position changed from the anterior to the posterior side of the dentition. This indicated that jaw muscle activity had declined.

  12. The effects of biting and pulling on the forces generated during feeding in the Komodo dragon (Varanus komodoensis.

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    Domenic C D'Amore

    Full Text Available In addition to biting, it has been speculated that the forces resulting from pulling on food items may also contribute to feeding success in carnivorous vertebrates. We present an in vivo analysis of both bite and pulling forces in Varanus komodoensis, the Komodo dragon, to determine how they contribute to feeding behavior. Observations of cranial modeling and behavior suggest that V. komodoensis feeds using bite force supplemented by pulling in the caudal/ventrocaudal direction. We tested these observations using force gauges/transducers to measure biting and pulling forces. Maximum bite force correlates with both body mass and total body length, likely due to increased muscle mass. Individuals showed consistent behaviors when biting, including the typical medial-caudal head rotation. Pull force correlates best with total body length, longer limbs and larger postcranial motions. None of these forces correlated well with head dimensions. When pulling, V. komodoensis use neck and limb movements that are associated with increased caudal and ventral oriented force. Measured bite force in Varanus komodoensis is similar to several previous estimations based on 3D models, but is low for its body mass relative to other vertebrates. Pull force, especially in the ventrocaudal direction, would allow individuals to hunt and deflesh with high success without the need of strong jaw adductors. In future studies, pull forces need to be considered for a complete understanding of vertebrate carnivore feeding dynamics.

  13. The effects of biting and pulling on the forces generated during feeding in the Komodo dragon (Varanus komodoensis).

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    D'Amore, Domenic C; Moreno, Karen; McHenry, Colin R; Wroe, Stephen

    2011-01-01

    In addition to biting, it has been speculated that the forces resulting from pulling on food items may also contribute to feeding success in carnivorous vertebrates. We present an in vivo analysis of both bite and pulling forces in Varanus komodoensis, the Komodo dragon, to determine how they contribute to feeding behavior. Observations of cranial modeling and behavior suggest that V. komodoensis feeds using bite force supplemented by pulling in the caudal/ventrocaudal direction. We tested these observations using force gauges/transducers to measure biting and pulling forces. Maximum bite force correlates with both body mass and total body length, likely due to increased muscle mass. Individuals showed consistent behaviors when biting, including the typical medial-caudal head rotation. Pull force correlates best with total body length, longer limbs and larger postcranial motions. None of these forces correlated well with head dimensions. When pulling, V. komodoensis use neck and limb movements that are associated with increased caudal and ventral oriented force. Measured bite force in Varanus komodoensis is similar to several previous estimations based on 3D models, but is low for its body mass relative to other vertebrates. Pull force, especially in the ventrocaudal direction, would allow individuals to hunt and deflesh with high success without the need of strong jaw adductors. In future studies, pull forces need to be considered for a complete understanding of vertebrate carnivore feeding dynamics.

  14. Bite force evaluation in subjects with cleft lip and palate

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    Carla Renata Sipert

    2009-04-01

    Full Text Available The purpose of this study was to evaluate the masticatory function of subjects with cleft lip and palate by analyzing the bite force developed by these individuals. Bite force was evaluated in a group of 27 individuals with repaired unilateral cleft lip and palate (14 males and 13 females - aged 18-26 years and compared to the data achieved from a group of 20 noncleft subjects (10 males and 10 females - aged 18-26 years. Measurement was achieved on three positions within the dental arch (incisors, right molars and left molars, three times at each position considering the highest value for each one. Statistical analysis was performed by ANOVA and Mann-Whitney test ( α = 5%. There was a significant deficit in bite force in male individuals with cleft lip and palate compared to the male control group (p=0.02, p=0.004, p=0.003 for incisors, right and left molars, respectively. For the female group, the difference was not statistically significant (p=0.79, p=0.06, p=0.47. In the group of individuals with clefts, 92.6% were under orthodontic treatment, which could be a reason for the present findings, since it can decrease the bite force more remarkably in males than in females. In conclusion, the bite force is significantly reduced in men when comparing the cleft group to the noncleft group. In females, this reduction was not significant in the same way. However, the main reason for this reduction and for the different behavior between genders should be further investigated.

  15. Fast and Powerful: Biomechanics and Bite Forces of the Mandibles in the American Cockroach Periplaneta americana.

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    Tom Weihmann

    Full Text Available Knowing the functionality and capabilities of masticatory apparatuses is essential for the ecological classification of jawed organisms. Nevertheless insects, especially with their outstanding high species number providing an overwhelming morphological diversity, are notoriously underexplored with respect to maximum bite forces and their dependency on the mandible opening angles. Aiming for a general understanding of insect biting, we examined the generalist feeding cockroach Periplaneta americana, characterized by its primitive chewing mouth parts. We measured active isometric bite forces and passive forces caused by joint resistance over the entire mandibular range with a custom-built 2D force transducer. The opening angle of the mandibles was quantified by using a video system. With respect to the effective mechanical advantage of the mandibles and the cross-section areas, we calculated the forces exerted by the mandible closer muscles and the corresponding muscle stress values. Comparisons with the scarce data available revealed close similarities of the cockroaches' mandible closer stress values (58 N/cm2 to that of smaller specialist carnivorous ground beetles, but strikingly higher values than in larger stag beetles. In contrast to available datasets our results imply the activity of faster and slower muscle fibres, with the latter becoming active only when the animals chew on tough material which requires repetitive, hard biting. Under such circumstances the coactivity of fast and slow fibres provides a force boost which is not available during short-term activities, since long latencies prevent a specific effective employment of the slow fibres in this case.

  16. Clinical significance of isometric bite force versus electrical activity in temporal and masseter muscles

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    Bakke, Merete; Michler, L; Han, K

    1989-01-01

    significant with respect to unilateral, but not to bilateral force measurements. Only in the masseter muscle was strength of dynamic contractions during chewing significantly correlated to bite force. With the present method it was demonstrated that unilateral bite force is a simple clinical indicator...

  17. The correlation between surface electromyography and bite force of mastication muscles in Asian young adults.

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    Yen, Cheng-I; Mao, Shih-Hsuan; Chen, Chih-Hao; Chen, Chien-Tzung; Lee, Ming-Yih

    2015-05-01

    Mastication function is related to mandible movement, muscle strength, and bite force. No standard device for measuring bite force has been developed. A linear relationship between electromyographic activity and bite force has been reported by several investigators, but data on the reliability of this relationship remain limited in Asian young adults. The purpose of this study was to develop a clinically applicable, reliable, quantitative, and noninvasive system to measure the kinetic mastication function and observe the correlation between surface electromyography (sEMG) and bite force. The study group consisted of 41 young healthy adults (24 men and 17 women). Surface electromyography was used to evaluate bilateral temporalis and masseter muscle activities, and an occlusal bite force system was used concurrently to measure the bite force during maximal voluntary biting. Bilateral symmetry was compared, and the correlation between EMG and bite force was calculated. The sEMG signals were 107.7±55.0 μV and 106.0±56.0 μV (P=0.699) on right and left temporalis muscles and 183.7±86.2 μV and 194.8±94.3 μV (P=0.121) on right and left masseter muscles, respectively. The bite force was 5.0±3.2 kg on the right side and 5.7±4.0 kg on the left side (P=0.974). A positive correlation between sEMG and bite force was observed. The correlation coefficient between the temporalis muscle and bite force was 0.512, and that between the masseter muscle and bite force was 0.360. No significant difference between the bilateral electromyographic activities of the temporalis and masseter muscles and bilateral bite force was observed in young healthy adults in Taiwan. A positive correlation between sEMG signals and bite force was noted. By combining sEMG and bite force, we developed a clinically applicable, quantitative, reliable, and noninvasive system for evaluating mastication function by using characteristics of biofeedback.

  18. Comparative analysis of methods for determining bite force in the spiny dogfish Squalus acanthias.

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    Huber, Daniel Robert; Motta, Philip Jay

    2004-01-01

    Many studies have identified relationships between the forces generated by the cranial musculature during feeding and cranial design. Particularly important to understanding the diversity of cranial form amongst vertebrates is knowledge of the generated magnitudes of bite force because of its use as a measure of ecological performance. In order to determine an accurate morphological proxy for bite force in elasmobranchs, theoretical force generation by the quadratomandibularis muscle of the spiny dogfish Squalus acanthias was modeled using a variety of morphological techniques, and lever-ratio analyses were used to determine resultant bite forces. These measures were compared to in vivo bite force measurements obtained with a pressure transducer during tetanic stimulation experiments of the quadratomandibularis. Although no differences were found between the theoretical and in vivo bite forces measured, modeling analyses indicate that the quadratomandibularis muscle should be divided into its constituent divisions and digital images of the cross-sections of these divisions should be used to estimate cross-sectional area when calculating theoretical force production. From all analyses the maximum bite force measured was 19.57 N. This relatively low magnitude of bite force is discussed with respect to the ecomorphology of the feeding mechanism of S. acanthias to demonstrate the interdependence of morphology, ecology, and behavior in organismal design. Copyright 2004 Wiley-Liss, Inc.

  19. Effects of strong bite force on the facial vertical dimension of pembarong performers

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    C. Christina

    2017-06-01

    Full Text Available Background: A pembarong performer is a reog dancer who bites on a piece of wood inserted into his/her mouth in order to support a 60 kg Barongan or Dadak Merak mask. The teeth supporting this large and heavy mask are directly affected, as the strong bite force exerted during a dance could affect their vertical and sagital facial dimensions. Purpose: This study aimed to examine the influence of the bite force of pembarong performers due to their vertical and sagital facial dimensions. Methods: The study reported here involved fifteen pembarong performers and thirteen individuals with normal occlusion (with specific criteria. The bite force of these subjects was measured with a dental prescale sensor during its centric occlusion. A cephalometric variation measurement was subsequently performed on all subjects with its effects on their vertical and sagital facial dimensions being measured. Results: The bite force value of the pembarong performers was 394.3816 ± 7.68787 Newtons, while the normal occlusion was 371.7784 ± 4.77791 Newtons. There was no correlation between the bite force and the facial sagital dimension of these subjects. However, a significant correlation did exist between bite force and lower facial height/total facial height (LFH/TFH ratio (p = 0.013. Conversely, no significant correlation between bite force and posterior facial height/total facial height (PFH/TFH ratio (p = 0.785 was detected. There was an inverse correlation between bite force and LFH/TFH ratio (r = -.464. Conclusion: Bite force is directly related to the decrease in LFH/TFH ratio. Occlusal pressure exerted by the posterior teeth on the alveolar bone may increase bone density at the endosteal surface of cortical bone.

  20. The relationship between skull morphology, masticatory muscle force and cranial skeletal deformation during biting.

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    Toro-Ibacache, Viviana; Zapata Muñoz, Víctor; O'Higgins, Paul

    2016-01-01

    The human skull is gracile when compared to many Middle Pleistocene hominins. It has been argued that it is less able to generate and withstand high masticatory forces, and that the morphology of the lower portion of the modern human face correlates most strongly with dietary characteristics. This study uses geometric morphometrics and finite element analysis (FEA) to assess the relationship between skull morphology, muscle force and cranial deformations arising from biting, which is relevant in understanding how skull morphology relates to mastication. The three-dimensional skull anatomies of 20 individuals were reconstructed from medical computed tomograms. Maximal contractile muscle forces were estimated from muscular anatomical cross-sectional areas (CSAs). Fifty-nine landmarks were used to represent skull morphology. A partial least squares analysis was performed to assess the association between skull shape and muscle force, and FEA was used to compare the deformation (strains) generated during incisor and molar bites in two individuals representing extremes of morphological variation in the sample. The results showed that only the proportion of total muscle CSA accounted for by the temporalis appears associated with skull morphology, albeit weekly. However, individuals with a large temporalis tend to possess a relatively wider face, a narrower, more vertically oriented maxilla and a lower positioning of the coronoid process. The FEAs showed that, despite differences in morphology, biting results in similar modes of deformation for both crania, but with localised lower magnitudes of strains arising in the individual with the narrowest, most vertically oriented maxilla. Our results suggest that the morphology of the maxilla modulates the transmission of forces generated during mastication to the rest of the cranium by deforming less in individuals with the ability to generate proportionately larger temporalis muscle forces. Copyright © 2015 Elsevier GmbH. All

  1. Teeth grinding, oral motor performance and maximal bite force in cerebral palsy children.

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    Botti Rodrigues Santos, Maria Teresa; Duarte Ferreira, Maria Cristina; de Oliveira Guaré, Renata; Guimarães, Antonio Sergio; Lira Ortega, Adriana

    2015-01-01

    Identify whether the degree of oral motor performance is related to the presence of teeth grinding and maximal bite force values in children with spastic cerebral palsy. Ninety-five spastic cerebral palsy children with and without teeth grinding, according to caregivers' reports, were submitted to a comprehensive oral motor performance evaluation during the feeding process using the Oral Motor Assessment Scale. Maximal bite force was measured using an electronic gnathodynamometer. The teeth grinding group (n = 42) was younger, used anticonvulsant drugs, and was more frequently classified within the subfunctional oral motor performance category. Teeth grinding subfunctional spastic cerebral palsy children presented lower values of maximal bite force. The functional groups showing the presence or absence of teeth grinding presented higher values of maximal bite force compared with the subfunctional groups. In spastic cerebral palsy children, teeth grinding is associated with the worse oral motor performance. © 2015 Special Care Dentistry Association and Wiley Periodicals, Inc.

  2. Postural And Eye-Positional Effects On Human Biting Force: An Experimental Study

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    Altay Tabancacı

    2012-06-01

    Full Text Available Muscle groups affected on biting force are called temporal muscle as a major and masseter muscle as a minor. According to the human posture stability, forces of these muscles vary with the force directions. In this case, experimental investigation is strictly important such that biting force under different postural and eye- positional situations is changed. In this study, seven-male and seven-female within the age-range of 17-24 are considered corresponding to having with restorated molar tooth and without that type of tooth. With the help of specially designed biting fork, different posture- and eye-positions are investigated for experimental biting force analysis. Changes in eye-positions are not indicated significant difference for all postural positions. On one hand, it is obtained that biting force of no-filling tooth in men becomes maximum if facial muscles give full effort to biting. On the other hand, effect of facial muscles for women is not clearly noticed depending on the postural differences.

  3. Biting

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    ... Distraction works wonders with kids this age. If emotions and energy levels are running high or if boredom has set in, help redirect a little one's attention to a more positive activity, like dancing to music, coloring, or playing a game. Discipline usually is not necessary, since most kids ...

  4. Chewing side, bite force symmetry, and occlusal contact area of subjects with different facial vertical patterns

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    Simone Guimarães Farias Gomes

    2011-10-01

    Full Text Available Craniofacial dimensions influence oral functions; however, it is not known whether they are associated with function asymmetry. The objective of this study was to evaluate chewing side preference and lateral asymmetry of occlusal contact area and bite force of individuals with different craniofacial patterns. Seventy-eight dentate subjects were divided into 3 groups according to the VERT index as follows: (1 mesofacial, (2 brachyfacial and (3 dolichofacial. Chewing side preference was evaluated using jaw tracking equipment, occlusal contact area was measured by silicon registration of posterior teeth, and bite force was measured unilaterally on molar regions using 2.25 mm-thick sensors. Statistical analysis was performed using ANOVA on Ranks, Student's t-test, and Mann-Whitney tests at a 5% significance level. Mesofacial, brachyfacial, and dolichofacial subjects presented more occlusal contact area on the left side. Only dolichofacial subjects showed lateral asymmetry for bite force, presenting higher force on the left side. No statistically significant differences were found for chewing side preference among all groups. Within the limitations of this study, it can be concluded that craniofacial dimensions play a role in asymmetry of bite force. ClinicalTrials.gov ID: NCT01286363.

  5. Relationship between oral status and maximum bite force in preschool children

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    Ching-Ming Su

    2009-03-01

    Conclusion: By combining the results of this study, it was concluded that associations of bite force with factors like age, maximum mouth opening and the number of teeth in contact were clearer than for other variables such as body height, body weight, occlusal pattern, and tooth decay or fillings.

  6. A preliminary study to find out maximum occlusal bite force in Indian individuals

    DEFF Research Database (Denmark)

    Jain, Veena; Mathur, Vijay Prakash; Pillai, Rajath

    2014-01-01

    PURPOSE: This preliminary hospital based study was designed to measure the mean maximum bite force (MMBF) in healthy Indian individuals. An attempt was made to correlate MMBF with body mass index (BMI) and some of the anthropometric features. METHODOLOGY: A total of 358 healthy subjects in the ag...

  7. Risk factors for low molar bite force in adult orthodontic patients

    DEFF Research Database (Denmark)

    Andersen, Malene Krogh; Sonnesen, Ane Liselotte

    2013-01-01

    in intercuspidal position, and symptoms and signs of temporomandibular disorders (TMD) were evaluated by TMD screening. Associations were assessed by Spearman correlations, Wilcoxon signed-rank sum test, and multiple stepwise regression analyses. Associations were found between bite force and craniofacial...

  8. Differences in bite force between dolichofacial and brachyfacial individuals: Side of mastication, gender, weight and height.

    Science.gov (United States)

    Quiudini, Paulo Roberto; Pozza, Daniel Humberto; Pinto, Ary Dos Santos; de Arruda, Mauricio Ferraz; Guimarães, Antonio Sergio

    2017-07-01

    Due to the bite force importance in functionality of the masticatory system, this study aimed to characterize it in dolichofacial and brachyfacial individuals. A sample comprised by 190 patients was divided into two groups: 90 severe dolichofacial, and 100 severe brachyfacial individuals classified according to the VERT index and the face height ratio (Jarabak quotient). Bite force was measured by using an adjusted digital dynamometer and proper methodology. The sample met the parametric assumptions and presented statistical significance when right and left sides of dolichofacial and brachyfacial individuals were compared. However, within the same group, no differences between the left and right sides were found. Generally, bite force was higher for male, left masticator, age between 41-50 years, weighing over 100kg and between 1.81 and 1.90m tall. Based on the results of this cross-sectional study, it was possible to conclude that the bite force in severe brachyfacial individuals was significantly higher than in severe dolichofacial individuals, being influenced by gender, weight and height. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  9. Biting Force and Muscle Activity in Implant-Supported Single Mandibular Overdentures Opposing Fixed Maxillary Dentition.

    Science.gov (United States)

    Al-Magaleh, Wafaʼa R; Abbas, Nadia A; Amer, Ashraf A; Abdelkader, Ann A; Bahgat, Basma

    2016-04-01

    This study aimed to investigate the relation between biting force and masticatory muscle activity in patients treated by 3 modalities of single mandibular dentures. Forty implants were placed in 10 patients with completely edentulous mandibles. The study was divided into 3 treatment stages. Initially, each patient received a conventional mandibular complete denture. At the second stage, 4 mandibular implants were placed and the denture was refitted to their abutments. Third stage comprised connecting the denture to the implants through ball attachments. During each treatment stage, maximum biting force and muscle activity were measured during maximum clenching and chewing of soft and hard food. Biting force demonstrated a statistically significant increase by time for the 3 treatment stages. The highest muscle activity was recorded for the conventional denture followed by the implant-supported overdenture without attachment, whereas the lowest values were recorded for the implant-supported overdenture with attachment. Biting force was related mainly to the quality of denture support. Muscle activity was higher in patients with conventional denture than with implant-supported prostheses (with or without attachments).

  10. Facial dimensions, bite force and masticatory muscle thickness in preschool children with functional posterior crossbite

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    Paula Midori Castelo

    2008-03-01

    Full Text Available Posterior crossbite may affect craniofacial growth and development. Thus, this study aimed to associate facial dimensions (by standardized frontal photographs to masseter and anterior portion of the temporal muscle thickness (by ultrasonography and maximal bilateral bite force in 49 children with deciduous and early mixed dentitions. They were distributed in four groups: deciduous-normal occlusion (DNO, n = 15, deciduous-crossbite (DCB, n = 10, mixed-normal occlusion (MNO, n = 13 and mixed-crossbite (MCB, n = 11. Anterior facial height (AFH, bizygomatic width (FWB, and intergonial width (FWI were determined and associated with muscle thickness and bite force, applying Pearson’s coefficients and multiple logistic regression, with age, gender, body weight and height as the covariates. FWB and FWI were correlated positively with the masseter thickness, whereas AFH/FWB and AFH/FWI ratios had negative correlation, except in the DNO group. The correlation between AFH/FWB and bite force in the MCB group was significantly negative. A higher AFH/FWB in MNO and MCB led to a significantly higher probability for functional crossbite development. In the studied sample, it was observed that children in the early mixed dentition with a long-face trend showed lower bite force and higher probability to present functional posterior crossbite, without significant influence of the covariates.

  11. The effect of lower anterior high pull headgear on treatment of moderate open bite in adults

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    Rahman Showkatbakhsh

    2012-01-01

    Full Text Available Background and Aims: Various methods are used for treatment of open bite. The objective of this study was to investigate the effects of Lower Anterior High Pull Headgear (LAHPH appliance in Class I subjects with moderate open bite and high lower lip line.Materials and Methods: The study group was composed of 10 subjects with a mean age of 15.8±2.5 years and 3.05 ± 0.07 mm moderate open bite. All the patients rejected orthognathic surgery. The treatment included extraction of upper and lower second premolars followed by leveling, banding, bonding, posterior space closure, and anterior retraction. After these procedures, the open bite was reduced to 2.04±1.17 mm. Afterwards, LAHPH was applied for 18 hours per day for 8±2 months. LAHPH appliance was composed of High Pull Headgear and two hooks mounted on its inner bow. Two elastics (1.8, light, Dentaurum connected the upper hooks on the inner bow to the lower hooks on the mandibular canines vertically. The forces produced by the prescribed elastics were 10 and 60 g during mouth closing and opening, respectively. Paired T-test was used to evaluate pre-andpost-treatment outcomes.Results: The pre-and post-treatment cephalometric evaluations showed that the LAHPH reduced effectively the open bite of the patients to 0.15±1.7 mm (P<0.001.Conclusion: This appliance can be used as an acceptable method for closing the open bite in Class I subjects.

  12. Does pain in the masseter and anterior temporal muscles influence maximal bite force?

    Science.gov (United States)

    Goiato, Marcelo Coelho; Zuim, Paulo Renato Junqueira; Moreno, Amália; Dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas; de Caxias, Fernanda Pereira; Turcio, Karina Helga Leal

    2017-11-01

    The aim of this study was to evaluate changes in pain and muscle force, and the relationship between them, in patients with muscle pain and bruxism, prior to and after treatment. Thirty women with bruxism and myofascial pain (Ia) were included in this study. Sleep bruxism diagnosis was made based on clinical diagnostic criteria, and awake bruxism diagnosis was made by patient questionnaires and the presence of tooth wear. The diagnosis of myofascial pain was established according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC-TMD). Dentulous or partially edentulous patients (rehabilitated with conventional fixed prostheses) were included in the study according to the inclusion and exclusion criteria. The pain treatment protocol included occlusal splints, patient education, and physiotherapy for 30days. Bite force was measured using a dynamometer at the central incisor and the first molar regions on both sides. The exams were performed at baseline, after 7days, and 30days after treatment. The Wilcoxon test was used to compare patient pain level response among the periods analyzed in the study. Bite force data were submitted to two-way repeated-measures ANOVA, followed by the Tukey HSD test (pforce. Results revealed that there was a statistical difference in pain level over time for both muscles and sides (pforce exhibited significantly higher values after 30days of treatment, when compared with the baseline (pforce only for the temporal muscle in all periods analyzed (pforce. Pain level decreased and bite force increased in the molar region after treatment. No strong correlation or dispersion in the relationship between pain levels and bite force was seen in women with myofascial pain and bruxism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Novel System for Bite-Force Sensing and Monitoring Based on Magnetic Near Field Communication

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    Jesús Sanz Maudes

    2012-08-01

    Full Text Available Intraoral devices for bite-force sensing have several applications in odontology and maxillofacial surgery, as bite-force measurements provide additional information to help understand the characteristics of bruxism disorders and can also be of help for the evaluation of post-surgical evolution and for comparison of alternative treatments. A new system for measuring human bite forces is proposed in this work. This system has future applications for the monitoring of bruxism events and as a complement for its conventional diagnosis. Bruxism is a pathology consisting of grinding or tight clenching of the upper and lower teeth, which leads to several problems such as lesions to the teeth, headaches, orofacial pain and important disorders of the temporomandibular joint. The prototype uses a magnetic field communication scheme similar to low-frequency radio frequency identification (RFID technology (NFC. The reader generates a low-frequency magnetic field that is used as the information carrier and powers the sensor. The system is notable because it uses an intra-mouth passive sensor and an external interrogator, which remotely records and processes information regarding a patient’s dental activity. This permits a quantitative assessment of bite-force, without requiring intra-mouth batteries, and can provide supplementary information to polysomnographic recordings, current most adequate early diagnostic method, so as to initiate corrective actions before irreversible dental wear appears. In addition to describing the system’s operational principles and the manufacture of personalized prototypes, this report will also demonstrate the feasibility of the system and results from the first in vitro and in vivo trials.

  14. Morphometry, bite-force, and paleobiology of the late miocene caiman Purussaurus brasiliensis.

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    Tito Aureliano

    Full Text Available Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force. The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts.

  15. Morphometry, Bite-Force, and Paleobiology of the Late Miocene Caiman Purussaurus brasiliensis

    Science.gov (United States)

    Aureliano, Tito; Ghilardi, Aline M.; Guilherme, Edson; Souza-Filho, Jonas P.; Cavalcanti, Mauro; Riff, Douglas

    2015-01-01

    Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

  16. Bone-breaking bite force of Basilosaurus isis (Mammalia, Cetacea from the late Eocene of Egypt estimated by finite element analysis.

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    Eric Snively

    Full Text Available Bite marks suggest that the late Eocence archaeocete whale Basilosaurus isis (Birket Qarun Formation, Egypt fed upon juveniles of the contemporary basilosaurid Dorudon atrox. Finite element analysis (FEA of a nearly complete adult cranium of B. isis enables estimates of its bite force and tests the animal's capabilities for crushing bone. Two loadcases reflect different biting scenarios: 1 an intitial closing phase, with all adductors active and a full condylar reaction force; and 2 a shearing phase, with the posterior temporalis active and minimized condylar force. The latter is considered probable when the jaws were nearly closed because the preserved jaws do not articulate as the molariform teeth come into occulusion. Reaction forces with all muscles active indicate that B. isis maintained relatively greater bite force anteriorly than seen in large crocodilians, and exerted a maximum bite force of at least 16,400 N at its upper P3. Under the shearing scenario with minimized condylar forces, tooth reaction forces could exceed 20,000 N despite lower magnitudes of muscle force. These bite forces at the teeth are consistent with bone indentations on Dorudon crania, reatract-and-shear hypotheses of Basilosaurus bite function, and seizure of prey by anterior teeth as proposed for other archaeocetes. The whale's bite forces match those estimated for pliosaurus when skull lengths are equalized, suggesting similar tradeoffs of bite function and hydrodynamics. Reaction forces in B. isis were lower than maxima estimated for large crocodylians and carnivorous dinosaurs. However, comparison of force estimates from FEA and regression data indicate that B. isis exerted the largest bite forces yet estimated for any mammal, and greater force than expected from its skull width. Cephalic feeding biomechanics of Basilosaurus isis are thus consistent with habitual predation.

  17. Mandibular kinematics and maximum voluntary bite force following segmental resection of the mandible without or with reconstruction.

    Science.gov (United States)

    Linsen, Sabine S; Oikonomou, Annina; Martini, Markus; Teschke, Marcus

    2018-05-01

    The purpose was to analyze mandibular kinematics and maximum voluntary bite force in patients following segmental resection of the mandible without and with reconstruction (autologous bone, alloplastic total temporomandibular joint replacement (TMJ TJR)). Subjects operated from April 2002 to August 2014 were enrolled in the study. Condylar (CRoM) and incisal (InRoM) range of motion and deflection during opening, condylar retrusion, incisal lateral excursion, mandibular rotation angle during opening, and maximum voluntary bite force were determined on the non-affected site and compared between groups. Influence of co-factors (defect size, soft tissue deficit, neck dissection, radiotherapy, occlusal contact zones (OCZ), and time) was determined. Twelve non-reconstructed and 26 reconstructed patients (13 autologous, 13 TMJ TJR) were included in the study. InRoM opening and bite force were significantly higher (P ≤ .024), and both condylar and incisal deflection during opening significantly lower (P ≤ .027) in reconstructed patients compared with non-reconstructed. Differences between the autologous and the TMJ TJR group were statistically not significant. Co-factors defect size, soft tissue deficit, and neck dissection had the greatest impact on kinematics and number of OCZs on bite force. Reconstructed patients (both autologous and TMJ TJR) have better overall function than non-reconstructed patients. Reconstruction of segmental mandibular resection has positive effects on mandibular function. TMJ TJR seems to be a suitable technique for the reconstruction of mandibular defects including the TMJ complex.

  18. Occlusal bite force change after orthodontic treatment with Andresen functional appliance.

    Science.gov (United States)

    Al-Khateeb, Susan N; Abu Alhaija, Elham S; Majzoub, Sami

    2015-04-01

    The aim of this study was to determine the occlusal bite force (OBF) changes, at the incisal and molar regions, after orthodontic treatment with functional appliance therapy in preadolescent subjects. OBF was measured for patients (17 females and 16 males) before and after the treatment with Andresen functional appliance for an average period of 9 months (mean age was 11.8±1.1 years). Three variables were registered; maximum OBF at molar region and the average of three readings at the molar (AOBF) and incisal regions (IOBF). The same variables were measured in two occasions for a matching non-treated control group with a period of 9 months between the two measurements. No significant changes were seen in the OBF measured parameters in the control group. There was a reduction in all measured parameters. The mean reduction in maximum OBF was 76.1±12.4 N (P appliance caused a significant reduction in OBF immediately after treatment. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Class II young adult treatment with Twin Force Bite corrector: 10-year follow-up

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    Ozge Uslu-Akcam

    2017-01-01

    Full Text Available One of the most preferred compliance free fixed functional appliances in nongrowing patients is Twin Force Bite corrector (TFBC. The aim of this case report is to evaluate the effectiveness of TFBC in the treatment of an adult Class II case. A 16-year 1-month-old boy having skeletal and dental Class II relationship was selected. Roth 0.018 × 0.025 inch slots brackets were attached; a fixed lingual arch in the mandibular dental arch and a Nance appliance in the maxillary dental arch were used to increase anchorage. The TFBC therapy used for sagittal activation and stimulation of forward mandibular growth lasted for 3 months. The post-TFBC treatment lasted 6 months and the total treatment time was 9 months. Treatment of a young adult Class II malocclusion with TFBC resulted in a Class I molar occlusion, an ideal overjet, overbite, and incisor angulation in a short time and maintained in the 10-year follow-up.

  20. Intraoral conversion of occlusal force to electricity and magnetism by biting of piezoelectric elements.

    Science.gov (United States)

    Kameda, Takashi; Ohkuma, Kazuo; Sano, Natsuki; Ogura, Hideo; Terada, Kazuto

    2012-01-01

    Very weak electrical, magnetic and ultrasound signal stimulations are known to promote the formation, metabolism, restoration and stability of bone and surrounding tissues after treatment and operations. We have therefore investigated the possibility of intraoral generation of electricity and magnetism by occlusal force in an in vitro study. Biting bimorph piezoelectric elements with lead zirconate titanate (PZT) using dental models generated appropriate magnetism for bone formation, i. e. 0.5-0.6 gauss, and lower electric currents and higher voltages, i. e. 2.0-6.0 μA at 10-22 V (appropriate levels are 30 μA and 1.25 V), as observed by a universal testing machine. The electric currents and voltages could be changed using amplifier circuits. These results show that intraoral generation of electricity and magnetism is possible and could provide post-operative stabilization and activation of treated areas of bone and the surrounding tissues directly and/or indirectly by electrical, magnetic and ultrasound stimulation, which could accelerate healing.

  1. Effects of gape and tooth position on bite force and skull stress in the dingo (Canis lupus dingo using a 3-dimensional finite element approach.

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    Jason Bourke

    Full Text Available Models of the mammalian jaw have predicted that bite force is intimately linked to jaw gape and to tooth position. Despite widespread use, few empirical studies have provided evidence to validate these models in non-human mammals and none have considered the influence of gape angle on the distribution of stress. Here using a multi-property finite element (FE model of Canis lupus dingo, we examined the influence of gape angle and bite point on both bite force and cranial stress. Bite force data in relation to jaw gape and along the tooth row, are in broad agreement with previously reported results. However stress data showed that the skull of C. l. dingo is mechanically suited to withstand stresses at wide gapes; a result that agreed well with previously held views regarding carnivoran evolution. Stress data, combined with bite force information, suggested that there is an optimal bite angle of between 25 degrees and 35 degrees in C. l. dingo. The function of these rather small bite angles remains unclear.

  2. Two-year follow-up of changes in bite force and occlusal contact area after intraoral vertical ramus osteotomy with and without Le Fort I osteotomy.

    Science.gov (United States)

    Choi, Y J; Lim, H; Chung, C J; Park, K H; Kim, K H

    2014-06-01

    This study was performed to examine the longitudinal changes in bite force and occlusal contact area after mandibular setback surgery via intraoral vertical ramus osteotomy (IVRO). Patients with mandibular prognathism who underwent IVRO (surgical group: 39 men and 39 women) were compared with subjects with class I skeletal and dental relationships (control group; 32 men and 35 women). The surgical group was divided into two subgroups: 1-jaw surgery (n = 30) and 2-jaw surgery (n = 48). Bite force and contact area were measured in maximum intercuspation with the Dental Prescale System before treatment, within 1 month before surgery, and at 1, 3, 6, 9, 12, and 24 months postsurgery. A linear mixed model was used to investigate the time-dependent changes and associated factors. Bite force and contact area decreased during presurgical orthodontic treatment, were minimal at 1 month postsurgery, and increased gradually thereafter. The 1-jaw and 2-jaw subgroups showed no significant differences in bite force. The time-dependent changes in bite force were significantly different according to the contact area (P contact area gradually increase throughout the postsurgical evaluation period. Increasing the occlusal contact area may be essential for improving bite force after surgery. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  3. Human bites (image)

    Science.gov (United States)

    Human bites present a high risk of infection. Besides the bacteria which can cause infection, there is ... the wound extends below the skin. Anytime a human bite has broken the skin, seek medical attention.

  4. Sex-specific trade-offs and compensatory mechanisms: bite force and sprint speed pose conflicting demands on the design of geckos (Hemidactylus frenatus).

    Science.gov (United States)

    Cameron, S F; Wynn, M L; Wilson, R S

    2013-10-15

    One of the more intuitive viability costs that can result from the possession of exaggerated sexually selected traits is increased predation pressure as a result of reduced locomotor capacity. Despite mixed empirical support for such locomotor costs, recent studies suggest that such costs may be masked by compensatory traits that effectively offset any detrimental effects. In this study, we provide a comprehensive assessment of the locomotor costs associated with improved male-male competitive ability by simultaneously testing for locomotor trade-offs and potential compensatory mechanisms in territorial male and non-territorial female geckos. Fighting capacity and escape performance of male Asian house geckos (Hemidactylus frenatus) are likely to pose conflicting demands on the optimum phenotype for each task. Highly territorial and aggressive males may require greater investment in head size/strength but such an enhancement may affect overall escape performance. Among male geckos, we found that greater biting capacity because of larger head size was associated with reduced sprint performance; this trade-off was further exacerbated when sprinting on an incline. Females, however, showed no evidence of this trade-off on either flat or inclined surfaces. The sex specificity of this trade-off suggests that the sexes differ in their optimal strategies for dealing with the conflicting requirements of bite force and sprint speed. Unlike males, female H. frenatus had a positive association between hind-limb length and head size, suggesting that they have utilised a compensatory mechanism to alleviate the possible locomotor costs of larger head sizes. It appears that there is greater selection on traits that improve fighting ability (bite force) for males, but it is viability traits (sprint speed) that appear to be of greater importance for females. Our results emphasise that only by examining both functional trade-offs and potential compensatory mechanisms is it possible

  5. Chewing efficiency and maximum bite force with different attachment systems of implant overdentures: a crossover study.

    Science.gov (United States)

    Elsyad, Moustafa Abdou; Khairallah, Ahmed Samir

    2017-06-01

    This crossover study aimed to evaluate and compare chewing efficiency and maximum bite force (MBF) with resilient telescopic and bar attachment systems of implant overdentures in patients with atrophied mandibles. Ten participants with severely resorbed mandibles and persistent denture problems received new maxillary and mandibular conventional dentures (control, CD). After 3 months of adaptation, two implants were inserted in canine region of the mandible. In a quasi-random method, overdentures were connected to the implants with either bar overdentures (BOD) or resilient telescopic overdentures (TOD) attachment systems. Chewing efficiency in terms of unmixed fraction (UF) was measured using chewing gum (after 5, 10, 20, 30 and 50 strokes), and MBF was measured using a bite force transducer. Measurements were performed 3 months after using each of the following prostheses: CD, BOD and TOD. Chewing efficiency and MBF increased significantly with BOD and TOD compared to CD. As the number of chewing cycles increased, the UF decreased. TOD recorded significant higher chewing efficiency and MBF than BOD. Resilient telescopic attachments are associated with increased chewing efficiency and MBF compared bar attachments when used to retain overdentures to the implants in patients with atrophied mandibles. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Loss of Axon Bifurcation in Mesencephalic Trigeminal Neurons Impairs the Maximal Biting Force in Npr2-Deficient Mice

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    Gohar Ter-Avetisyan

    2018-06-01

    Full Text Available Bifurcation of axons from dorsal root ganglion (DRG and cranial sensory ganglion (CSG neurons is mediated by a cGMP-dependent signaling pathway composed of the ligand C-type natriuretic peptide (CNP, the receptor guanylyl cyclase Npr2 and the cGMP-dependent protein kinase I (cGKI. Here, we demonstrate that mesencephalic trigeminal neurons (MTN which are the only somatosensory neurons whose cell bodies are located within the CNS co-express Npr2 and cGKI. Afferents of MTNs form Y-shaped branches in rhombomere 2 where the ligand CNP is expressed. Analyzing mouse mutants deficient for CNP or Npr2 we found that in the absence of CNP-induced cGMP signaling MTN afferents no longer bifurcate and instead extend either into the trigeminal root or caudally in the hindbrain. Since MTNs provide sensory information from jaw closing muscles and periodontal ligaments we measured the bite force of conditional mouse mutants of Npr2 (Npr2flox/flox;Engr1Cre that lack bifurcation of MTN whereas the bifurcation of trigeminal afferents is normal. Our study revealed that the maximal biting force of both sexes is reduced in Npr2flox/flox;Engr1Cre mice as compared to their Npr2flox/flox littermate controls. In conclusion sensory feedback mechanisms from jaw closing muscles or periodontal ligaments might be impaired in the absence of MTN axon bifurcation.

  7. Forças de mordida relacionadas a próteses parciais removíveis inferiores Biting forces related to partially removable mandibular dentures

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    Eduardo Piza PELLIZZER

    1998-10-01

    Full Text Available A pesquisa teve como objetivo determinar as forças de mordida de 73 indivíduos, por meio de um gnatodinamômetro. Os pacientes eram portadores de próteses parciais removíveis inferiores classes I, II ou III. A arcada antagonista era prótese, parcial removível ou fixa, ou total. Os resultados permitiram concluir que: as selas de extremidade livre, principalmente em suas posições extremas, conduziram a forças de mordida muito baixas; o envolvimento de prótese total, também, conduziu a forças de mordida baixas; o sexo masculino alcançou valores maiores que o feminino; com prótese parcial removível classe III, os dentes naturais molares e pré-molares desenvolveram valores maiores do que com classes I e II.The purpose of this study was to determine the biting forces of individuals wearing classes I, II or III partially removable mandibular dentures. Upper jaws presented fixed bridges, classes I, II or III partially removable dentures, or complete dentures. Measurements of biting forces were obtained by a gnathodynamometer. The conclusions were: classes I and II presented low biting forces, specially far from the last abutment tooth; when the opposite arcade was a complete denture, biting forces were low; males presented higher biting forces than females; natural molars and bicuspids presented higher biting forces with class III than with classes I or II.

  8. Effect of telescopic distal extension removable partial dentures on oral health related quality of life and maximum bite force: A preliminary cross over study.

    Science.gov (United States)

    Elsyad, Moustafa Abdou; Mostafa, Aisha Zakaria

    2018-01-01

    This cross over study aimed to evaluate the effect of telescopic distal extension removable partial dentures on oral health related quality of life and maximum bite force MATERIALS AND METHODS: Twenty patients with complete maxillary edentulism and partially edentulous mandibles with anterior teeth only remaining were selected for this cross over study. All patients received complete maxillary dentures and mandibular partial removable dental prosthesis (PRDP, control). After 3 months of adaptation, PRDP was replaced with conventional telescopic partial dentures (TPD) or telescopic partial dentures with cantilevered extensions (TCPD) in a quasi-random method. Oral health related quality of life (OHRQoL) was measured using OHIP-14 questionnaire and Maximum bite force (MBF) was measured using a bite force transducer. Measurements were performed 3 months after using each of the following prostheses; PRDP, TPD, and TCPD. TCPD showed the OHIP-14 lowest scores (i.e., the highest patient satisfaction with their OHRQoL), followed by TPD, and PRDP showed the highest OHIP-14 scores (i.e., the lowest patient satisfaction with OHRQoL). TCPD showed the highest MBF (70.7 ± 3.71), followed by TPD (57.4 ± 3.43) and the lowest MBF (40.2 ± 2.20) was noted with PRDP. WITHIN The Limitations of This Study, Mandibular Telescopic Distal Extension Removable Partial Dentures with Cantilevered Extensions Were Associated with Improved Oral Health Related Quality of Life and Maximum Bite Force Compared to Telescopic or Conventional PRDP. Telescopic distal extension removable prostheses is an esthetic restoration in partially edentulous patients with free end saddle. This article describes the addition of cantilevered extensions of this prosthesis. The results showed that telescopic distal extension removable prostheses with cantilevered extensions were associated with improved oral health related quality of life and maximum bite force compared to telescopic or conventional RPDs

  9. Interactive relationship between the mechanical properties of food and the human response during the first bite.

    Science.gov (United States)

    Dan, Haruka; Kohyama, Kaoru

    2007-05-01

    Biting is an action that results from interplay between food properties and the masticatory system. The mechanical factors of food that cause biting adaptation and the recursive effects of modified biting on the mechanical phenomena of food are largely unknown. We examined the complex interaction between the bite system and the mechanical properties. Nine subjects were each given a cheese sample and instructed to bite it once with their molar teeth. An intra-oral bite force-time profile was measured using a tactile pressure-measurement system with a sheet sensor inserted between the molars. Time, force, and impulse for the first peak were specified as intra-oral parameters of the sample fracture. Mechanical properties of the samples were also examined using a universal testing machine at various test speeds. Besides fracture parameters, initial slope was also determined as a mechanical property possibly sensed shortly after bite onset. The bite profile was then examined based on the mechanical parameters. Sample-specific bite velocities were identified as characteristic responses of a human bite. A negative correlation was found between bite velocity and initial slope of the sample, suggesting that the initial slope is the mechanical factor that modifies the consequent bite velocity. The sample-specific bite velocity had recursive effects on the following fracture event, such that a slow velocity induced a low bite force and high impulse for the intra-oral fracture event. We demonstrated that examination of the physiological and mechanical factors during the first bite can provide valuable information about the food-oral interaction.

  10. Implant-tooth-supported fixed partial prostheses: correlations between in vivo occlusal bite forces and marginal bone reactions.

    Science.gov (United States)

    Akça, Kivanç; Uysal, Serdar; Cehreli, Murat Cavit

    2006-06-01

    To evaluate maximal occlusal bite forces (MOF) and marginal bone level (MBL) changes in patients with implant-tooth-supported fixed partial prostheses (FPP). Twenty nine partially edentulous patients consecutively who received 34 three-occlusal unit FPP with terminal implant and tooth support were subjected to quantification of MOFs using a sub-miniature load cell connected to a data acquisition system and measurement of the MBL changes around implants in digitalized periapical radiographs obtained at prostheses delivery and 24-month follow-up. MOFs for implant support (mean: 353.61 N) significantly differed from tooth support (mean: 275.48 N) (P 0.05). MBL changes at mesial and distal sites of the implants at 24 months of functional loading were 0.28 and 0.097 mm respectively. Although MOFs under functional loading might indicate an increase in load participation for supporting implant, the rigid connection between implant and natural tooth via three-occlusal unit FPP does not jeopardize the time-dependent MBL stability of the implant under functional loads.

  11. [Mammal bite management].

    Science.gov (United States)

    Contreras-Marín, Misael; Sandoval-Rodríguez, Jorge Issac; García-Ramírez, Raúl; Morales-Yépez, Héctor Adolfo

    Animal bites are a major public health problem, it is estimated that 2% of the population is bitten each year. Most bites are by dogs and the risk factors include young children, men, certain breeds of dogs and untrained dogs. The risk of infection after bites differs between animal species and depends on the animal teeth and oral flora. Animal bites are still a major cause of morbidity in patients of all ages and have caused several preventable childhood deaths. These wounds often become infected. If the wound requires it, early surgical evaluation must be performed. The use of antibiotics is only recommended for high risk bite wounds. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  12. Impact velocities of the teeth after a sudden unloading at various initial bite forces, degrees of mouth opening, and distances of travel

    NARCIS (Netherlands)

    Nagashima, T; Slager, GEC; Broekhuijsen, ML; vanWilligen, JD

    A potentially dangerous situation arises when an individual bites on hard and brittle food which suddenly breaks, since the impact velocity of the lower teeth onto the upper teeth after the food is broken can be high and may cause dental damage. The present experiments were designed to study the

  13. Insect bites and stings

    Science.gov (United States)

    ... widow spider bite; Brown recluse bite; Flea bite; Honey bee or hornet sting; Lice bites; Mite bite; ... Saunders; 2016:chap 359. Otten EJ. Venomous animal injuries. In: Walls RM, Hockberger RS, Gausche-Hill M, ...

  14. Animal Bites

    Science.gov (United States)

    Wild animals usually avoid people. They might attack, however, if they feel threatened, are sick, or are protecting their ... or territory. Attacks by pets are more common. Animal bites rarely are life-threatening, but if they ...

  15. Influence of sustained submaximal clenching fatigue test on electromyographic activity and maximum voluntary bite forces in healthy subjects and patients with temporomandibular disorders.

    Science.gov (United States)

    Xu, L; Fan, S; Cai, B; Fang, Z; Jiang, X

    2017-05-01

    This study aimed to investigate whether the fatigue induced by sustained motor task in the jaw elevator muscles differed between healthy subjects and patients with temporomandibular disorder (TMD). Fifteen patients with TMD and thirteen age- and sex-matched healthy controls performed a fatigue test consisting of sustained clenching contractions at 30% maximal voluntary clenching intensity until test failure (the criterion for terminating the fatigue test was when the biting force decreased by 10% or more from the target force consecutively for >3 s). The pre- and post-maximal bite forces (MBFs) were measured. Surface electromyographic signals were recorded from the superficial masseter muscles and anterior temporal muscles bilaterally, and the median frequency at the beginning, middle and end of the fatigue test was calculated. The duration of the fatigue test was also quantified. Both pre- and post-MBFs were lower in patients with TMD than in controls (P fatigue test in TMD patients was significantly shorter than that of the controls (P fatigued, but the electromyographic activation process during the fatigue test is similar between healthy subjects and patients with TMD. However, the mechanisms involved in this process remain unclear, and further research is warranted. © 2017 John Wiley & Sons Ltd.

  16. Food aroma affects bite size

    Directory of Open Access Journals (Sweden)

    de Wijk René A

    2012-03-01

    Full Text Available Abstract Background To evaluate the effect of food aroma on bite size, a semisolid vanilla custard dessert was delivered repeatedly into the mouth of test subjects using a pump while various concentrations of cream aroma were presented retronasally to the nose. Termination of the pump, which determined bite size, was controlled by the subject via a push button. Over 30 trials with 10 subjects, the custard was presented randomly either without an aroma, or with aromas presented below or near the detection threshold. Results Results for ten subjects (four females and six males, aged between 26 and 50 years, indicated that aroma intensity affected the size of the corresponding bite as well as that of subsequent bites. Higher aroma intensities resulted in significantly smaller sizes. Conclusions These results suggest that bite size control during eating is a highly dynamic process affected by the sensations experienced during the current and previous bites.

  17. Human bites - self-care

    Science.gov (United States)

    Bites - human - self-care ... Human bites can occur in 2 ways: If someone bites you If your hand comes into contact ... bite to express anger or other negative feelings. Human bites may be more dangerous than animal bites. ...

  18. Cat and Dog Bites

    Science.gov (United States)

    ... Wellness Staying Healthy Pets and Animals Cat and Dog Bites Cat and Dog Bites Share Print Cat and dog bites are common injuries. A family pet or ... bites. Path to safety If a cat or dog bites you, you should: Wash the wound gently ...

  19. Low dose versus high dose anti-snake venom therapy in the treatment of haematotoxic snake bite in South India.

    Science.gov (United States)

    Joseph, Imanto M; Kuriakose, Cijoy K; Dev, Anand Vimal; Philip, George A

    2017-10-01

    Most of the studies on the appropriate dose of anti-snake venom (ASV) are from tertiary hospitals and the guidelines are unclear. Our observational study compared the outcomes of two prevalent treatment regimes for haematotoxic snake bite in a secondary care hospital in South India. The time to normalisation of whole blood clotting time, mortality and complications were not different between the groups. The average dose of ASV required in the low and high dose groups were 106 mL and 246 mL, respectively. Consequently, patients who received low dose ASV incurred approximately 50% less expense. Urticarial rashes were also significantly fewer in the low dose group.

  20. Insect Bites and Stings

    Science.gov (United States)

    Most insect bites are harmless, though they sometimes cause discomfort. Bee, wasp, and hornet stings and fire ant bites usually hurt. Mosquito and flea bites usually itch. Insects can also spread diseases. In the United States, ...

  1. Spider Bites (For Parents)

    Science.gov (United States)

    ... Videos for Educators Search English Español First Aid: Spider Bites KidsHealth / For Parents / First Aid: Spider Bites ... rare. Signs and Symptoms Of a brown recluse spider bite: red blister in the center with surrounding ...

  2. Venomous Snake Bite Injuries at Kitui District Hospital | Kihiko ...

    African Journals Online (AJOL)

    Background Snake bites are a neglected public health issue in poor rural communities, and the true burden of snake bites is not known. Kitui County has a high incidence of snake bites and no functional snake bite control programs exists. Diagnostic tests for snake species identification are not available and management ...

  3. Torix group Rickettsia are widespread in Culicoides biting midges (Diptera: Ceratopogonidae), reach high frequency and carry unique genomic features.

    Science.gov (United States)

    Pilgrim, Jack; Ander, Mats; Garros, Claire; Baylis, Matthew; Hurst, Gregory D D; Siozios, Stefanos

    2017-10-01

    There is increasing interest in the heritable bacteria of invertebrate vectors of disease as they present novel targets for control initiatives. Previous studies on biting midges (Culicoides spp.), known to transmit several RNA viruses of veterinary importance, have revealed infections with the endosymbiotic bacteria, Wolbachia and Cardinium. However, rickettsial symbionts in these vectors are underexplored. Here, we present the genome of a previously uncharacterized Rickettsia endosymbiont from Culicoides newsteadi (RiCNE). This genome presents unique features potentially associated with host invasion and adaptation, including genes for the complete non-oxidative phase of the pentose phosphate pathway, and others predicted to mediate lipopolysaccharides and cell wall modification. Screening of 414 Culicoides individuals from 29 Palearctic or Afrotropical species revealed that Rickettsia represent a widespread but previously overlooked association, reaching high frequencies in midge populations and present in 38% of the species tested. Sequence typing clusters the Rickettsia within the Torix group of the genus, a group known to infect several aquatic and hematophagous taxa. FISH analysis indicated the presence of Rickettsia bacteria in ovary tissue, indicating their maternal inheritance. Given the importance of biting midges as vectors, a key area of future research is to establish the impact of this endosymbiont on vector competence. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Animal Bites: First Aid

    Science.gov (United States)

    First aid Animal bites: First aid Animal bites: First aid By Mayo Clinic Staff These guidelines can help you care for a minor animal bite, such ... 26, 2017 Original article: http://www.mayoclinic.org/first-aid/first-aid-animal-bites/basics/ART-20056591 . Mayo ...

  5. Chewing efficiency, bite force and oral health-related quality of life with narrow diameter implants - a prospective clinical study: results after one year.

    Science.gov (United States)

    Enkling, Norbert; Saftig, Marcus; Worni, Andreas; Mericske-Stern, Regina; Schimmel, Martin

    2017-04-01

    This prospective study aimed to investigate the evolution of chewing efficiency, maximum voluntary bite force (MBF) and oral health-related quality of life (OHRQoL) in edentulous patients treated with narrow diameter implants (NDIs) over the course of 1 year. Four NDIs (MDI ® , 3M ESPE, diameter 1.8 mm) were placed interforaminally in 20 edentulous patients. They were immediately loaded by converting the existing prosthesis into an implant overdenture. Participants were examined six times pre- and postoperatively [baseline (BL) to week 52 (w52)]. Chewing efficiency was evaluated with a colour-mixing ability test by evaluation of the standard deviation of hue (VOH, ViewGum©). MBF was measured using a digital force gauge. OHRQoL was determined with the Oral Health Impact Profile (OHIPG49). Nonparametric Brunner-Langer models were applied for statistical testing. The study failed to demonstrate an effect on chewing efficiency. MBF increased continuously during the observation period (medians: MBF[N]@BL = 46.6 [iqr 50.1]; MBF[N]@w52 = 103.9 [iqr 76.0]; P = 0.002). OHRQoL increased steeply after implant loading and continued improving (medians: BL ∑OHIPG49 = 31 [iqr 40.0]; w4 ∑OHIPG49 = 11.5 [iqr 19.5]; w52 ∑OHIPG49 = 6 [iqr 13.0], P chewing instructions. Larger studies need to confirm a positive effect on chewing efficiency and develop long-term maintenance solutions if patients become frail because no easy downgrading approaches of one-piece titanium implants exist. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Modeling forces in high-temperature superconductors

    International Nuclear Information System (INIS)

    Turner, L. R.; Foster, M. W.

    1997-01-01

    We have developed a simple model that uses computed shielding currents to determine the forces acting on a high-temperature superconductor (HTS). The model has been applied to measurements of the force between HTS and permanent magnets (PM). Results show the expected hysteretic variation of force as the HTS moves first toward and then away from a permanent magnet, including the reversal of the sign of the force. Optimization of the shielding currents is carried out through a simulated annealing algorithm in a C++ program that repeatedly calls a commercial electromagnetic software code. Agreement with measured forces is encouraging

  7. Animal Bites of the Hand

    Science.gov (United States)

    ... Therapist? Media Find a Hand Surgeon Home Anatomy Animal Bites Email to a friend * required fields From * ... key to prevent problems from a bite. CAUSES Animal Bites Millions of animal bites occur in the ...

  8. Bug Bites and Stings

    Science.gov (United States)

    ... can carry other diseases, such as malaria and dengue fever. Spider Bites Most spider bites are minor, ... Clean the area with soap and water, and treat with an antiseptic or antibiotic cream to avoid ...

  9. Exotic reptile bites.

    Science.gov (United States)

    Kelsey, J; Ehrlich, M; Henderson, S O

    1997-09-01

    Reptiles are a growing part of the exotic pet trade, and reptile bites have been considered innocuous in the emergency medicine literature. Two cases are reported of reptile bites, one from a green iguana and the other from a reticulated python. The treatment concerns associated with reptile bites are discussed.

  10. Rat bite fever without fever.

    Science.gov (United States)

    Stehle, P; Dubuis, O; So, A; Dudler, J

    2003-09-01

    Rat bite fever is a rarely reported acute febrile bacterial illness caused by Streptobacillus moniliformis or Spirillum minus following a rat bite. It is classically characterised by abrupt onset of fever with rigors, myalgias, headache, and the appearance of a generalised maculopapular petechial skin rash. Polyarthritis complicates the course of the disease in up to 50% of infected patients, and numerous hurdles can make the diagnosis particularly difficult in the absence of fever or rash, as in the present case. A high degree of awareness is necessary to make the correct diagnosis in such cases. Diagnosis has important prognostic implications as the disease is potentially lethal, but easily treatable.

  11. Animal bites - self-care

    Science.gov (United States)

    Bites - animals - self-care ... Most animal bites come from pets. Dog bites are common and most often happen to children. Cat bites are ... which can cause deeper puncture wounds. Most other animal bites are caused by stray or wild animals, ...

  12. Estimation of Dog-Bite Risk and Related Morbidity Among Personnel Working With Military Dogs.

    Science.gov (United States)

    Schermann, H; Eiges, N; Sabag, A; Kazum, E; Albagli, A; Salai, M; Shlaifer, A

    Soldiers serving in the Israel Defense Force Military Working Dogs (MWD) Unit spend many hours taming dogs' special skills, taking them on combat missions, and performing various dogkeeping activities. During this intensive work with the aggressive military dogs, bites are common, and some of them result in permanent disability. However, this phenomenon has not been quantified or reported as an occupational hazard. This was a retrospective cohort study based on self-administered questionnaires. Information was collected about soldiers' baseline demographics, duration of the experience of working with dogs, total number of bites they had, circumstances of bite events, and complications and medical treatment of each bite. Bite risk was quantified by incidence, mean time to first bite, and a Cox proportional hazards model. Rates of complications and the medical burden of bites were compared between combat soldiers and noncombat dogkeepers. Bite locations were presented graphically. Seventy-eight soldiers participated and reported on 139 bites. Mean time of working with dogs was 16 months (standard deviation, ±9.4 months). Overall bite incidence was 11 bites per 100 person-months; the mean time to first bite event was 6.3 months. The Cox proportional hazards model showed that none of baseline characteristics significantly increased bite hazard. About 90% of bites occurred during routine activities, and 3.3% occurred on combat missions. Only in 9% of bite events did soldiers observed the safety precautions code. Bite complications included fractures, need for intravenous antibiotic treatment and surgical repair, prominent scarring, diminished sensation, and stiffness of proximal joints. Bite complications were similar between combat soldiers and dogkeepers. Most bites (57%) were located on hands and arms. MWD bites are an occupational hazard resulting in significant medical burden. Hands and arms were most common bite locations. Observance of safety precautions may be

  13. Evaluation of muscle activity, bite force and salivary cortisol in children with bruxism before and after low level laser applied to acupoints: study protocol for a randomised controlled trial.

    Science.gov (United States)

    Salgueiro, Mônica da Consolação Canuto; Bortoletto, Carolina Carvalho; Horliana, Anna Carolina RattoTempestini; Mota, Ana Carolina Costa; Motta, Lara Jansiski; Motta, Pamella de Barros; MesquitaFerrari, Raquel Agnelli; Fernandes, Kristianne Porta Santos; Bussadori, Sandra Kalil

    2017-08-08

    Bruxism is a repetitive activity that causes tooth wear, audible sounds, and discomfort. Preventive measures have been studied for conditions that can exert a negative influence on physiological development in children. Low-level laser therapy administered over acupoints is an effective, painless, low-cost treatment option that has achieved good results. Thus, the aim of the proposed study is to evaluate changes in muscle activity, bite force and salivary cortisol in children with bruxism after the application of low-level laser to accupoints. The children will be randomly allocated to four groups of 19 individuals: G1 - low-level laser; G2 - occlusal splint; G3 - placebo laser; and G4 - control (without bruxism). The BTS TMJOINT electromyography will be used to determine muscle activity and a digital gnathodynamometer will be used to measure bite force. Salivary cortisol will be analysed at baseline as well as one and six months after treatment. Two-way ANOVA will be employed and complemented by Tukey's test. Bruxism is a repetitive activity of the masticatory muscles that can have negative consequences if not treated, such as tooth wear, noises, discomfort and anxiety. Thus, control and treatment measures should be taken. Although low-level laser therapy over acupoints has been indicated for children, the effects of this treatment modality have not yet been studied. NCT02757261 on 8 April 2016. This study protocol received a grant from the Brazilian fostering agency São Paulo Research Foundation (FAPESP: #2015/24731-0).

  14. Roll force prediction of high strength steel using foil rolling theory in cold skin pass rolling

    International Nuclear Information System (INIS)

    Song, Gil Ho; Jung, Jae Chook

    2013-01-01

    Skin pass rolling is a very important process for applying a certain elongation to a strip in the cold rolling and annealing processes, which play an important role in preventing the stretching of the yield point when the material is processed. The exact prediction of the rolling force is essential for obtaining a given elongation with the steel grade and strip size. Unlike hot rolling and cold rolling, skin pass rolling is used to apply an elongation of within 2% to the strip. Under a small reduction, it is difficult to predict the rolling force because the elastic deformation behavior of the rolls is complicated and a model for predicting the rolling force has not yet been established. Nevertheless, the exact prediction of the rolling force in skin pass rolling has gained increasing importance in recent times with the rapid development of high strength steels for use in automobiles. In this study, the possibility of predicting the rolling force in skin pass rolling for producing various steel grades was examined using foil rolling theory, which is known to have similar elastic deformation behavior of rolls in the roll bite. It was found that a noncircular arc model is more accurate than a circular model in predicting the roll force of high strength steel below TS 980 MPa in skin pass rolling

  15. prevalence of biting and non-biting flies in relation to species

    African Journals Online (AJOL)

    USER

    support high abundance of biting flies due to the favourable conditions within the forest for breeding, refuge and easy migration of adult females to animal cages to seek for blood meal. Table 1: Abundance of Biting Flies in Relation to Species in the Jos Museum. Zoological Garden. Site. Stomoxys calcitrans. Haematopota.

  16. Spider Bites: First Aid

    Science.gov (United States)

    ... care immediately if: You were bitten by a black widow or brown recluse spider You are unsure whether the bite ... in the South. Signs and symptoms of a black widow spider bite may include: At ... fever and nausea Brown recluse spider The brown recluse spider has a ...

  17. K-9 Police Dog Bite

    Directory of Open Access Journals (Sweden)

    Vy Han

    2017-01-01

    Full Text Available History of present illness: A 30-year-old male who was brought into the emergency department (ED by police officers after being bitten in the right lower extremity by a police German Shepard after attempting to flee authorities on foot. The patient stated that the dog immediately bit down on his right calf and proceeded to violently shake its head side to side without releasing its grip until police manually pulled the dog off of him. Upon arrival to the ED, he was tachycardic in the 120’s, complaining of severe, throbbing, sharp pain in the right lower extremity, and was neurovascular intact on exam. Significant findings: The photograph is of the anterior compartment of the right lower leg demonstrating multiple deep lacerations with exposed and torn muscle. X-ray showed no foreign body. Discussion: Police dog bites should be treated more cautiously than typical dog bites because these highly-trained dogs are generally larger breeds which are taught to subdue suspects with a bite-and-hold technique rather than bite and release. This can lead to extensive crush injuries, fractures, large caliber lacerations with associated muscle tissue injury and/or severe neurovascular compromise.1 Hence, police dog bites often require provocative diagnostic testing, specialist consultation for possible operative repair, and aggressive irrigation and ultimately admission for intravenous antibiotics.1 This patient’s wound was aggressively irrigated and evaluated by plastic surgery in the ED. He was ultimately admitted for intravenous antibiotics, pain control, wound care, and healing by secondary intention.

  18. London forces in highly oriented pyrolytic graphite

    Directory of Open Access Journals (Sweden)

    L.V. Poperenko

    2017-07-01

    Full Text Available Surface of highly oriented pyrolytic graphite with terrace steps was studied using scanning tunneling microscopy with high spatial resolution. Spots with positive and negative charges were found in the vicinity of the steps. Values of the charges depended both on the microscope needle scan velocity and on its motion direction. The observed effect was theoretically explained with account of London forces that arise between the needle tip and the graphite surface. In this scheme, a terrace step works as a nanoscale diode for surface electric currents.

  19. Masticatory performance and bite force in children with primary dentition Performance mastigatória e força de mordida em crianças na dentição decídua

    Directory of Open Access Journals (Sweden)

    Maria Beatriz Duarte Gavião

    2007-06-01

    Full Text Available The aim of this study was to evaluate the relationship between masticatory performance and maximum bite force in the primary dentition. The sample comprised 15 children of both genders, aged 3 to 5.5 years, with good systemic and oral health, presence of all primary teeth without large caries, no structural anomalies, without severe malocclusion, and no history of orthodontic treatment. They chewed one standardized silicone tablet for 20 strokes and the median areas of the chewed particles were measured by an optical digital system. Enhanced performance was measured by a decrease in the chewed particle areas and an increase in the amount of chewed particles. The bite force was determined using a transmitter pressurized tube connected to an analog/digital electronic circuit. Weight, height and body mass index (kg/m² were determined. The data were analyzed by descriptive statistics and Pearson or Spearman's correlations, after assessment of the normality of the distribution by Shapiro-Wilks' W-test. There was no correlation between bite force and particle area and amount (p > 0.05, neither were the body variables correlated with the masticatory variables (p > 0.05. It was concluded that the bite force was not a primary determinant of masticatory performance, and both variables were not dependent on body variables in the studied sample.O objetivo deste estudo foi avaliar a correlação entre performance mastigatória e força de mordida máxima na dentição decídua. A amostra consistiu de 15 crianças de 3 a 5,5 anos de idade, de ambos os gêneros, apresentando boa saúde bucal e sistêmica, com a presença de todos os dentes decíduos, sem cáries extensas, sem anomalias estruturais, sem maloclusão severa e ausência de tratamento ortodôntico. Um tablete de silicone foi mastigado durante 20 ciclos e as áreas medianas das partículas foram mensuradas por um sistema óptico digital. A performance mastigatória foi considerada melhor quanto

  20. Fire Ant Bites

    Science.gov (United States)

    ... Favorite Name: Category: Share: Yes No, Keep Private Fire Ant Bites Share | Fire ants are aggressive, venomous insects that have pinching ... across the United States, even into Puerto Rico. Fire ant stings usually occur on the feet or ...

  1. Avoid Mosquito Bites

    Science.gov (United States)

    ... visiting CDC Travelers’ Health website . Pack a travel health kit . Remember to pack insect repellent and use it as directed to prevent mosquito bites. See a healthcare provider familiar with travel medicine, ideally 4 to 6 weeks ...

  2. Fighting and Biting

    Science.gov (United States)

    ... on Demand Maintenance of Certification and Lifelong Learning Modules Online CME Pathways My Profile Store Cart Donate ... child, or put the child down. For a young child (2-3 years) say, "biting is not ...

  3. Sultan - forced flow, high field test facility

    International Nuclear Information System (INIS)

    Horvath, I.; Vecsey, G.; Weymuth, P.; Zellweger, J.

    1981-01-01

    Three European laboratories: CNEN (Frascati, I) ECN (Petten, NL) and SIN (Villigen, CH) decided to coordinate their development efforts and to install a common high field forced flow test facility at Villigen Switzerland. The test facility SULTAN (Supraleiter Testanlage) is presently under construction. As a first step, an 8T/1m bore solenoid with cryogenic periphery will be ready in 1981. The cryogenic system, data acquisition system and power supplies which are contributed by SIN are described. Experimental feasibilities, including cooling, and instrumentation are reviewed. Progress of components and facility construction is described. Planned extension of the background field up to 12T by insert coils is outlined. 5 refs

  4. High-frequency multimodal atomic force microscopy

    Directory of Open Access Journals (Sweden)

    Adrian P. Nievergelt

    2014-12-01

    Full Text Available Multifrequency atomic force microscopy imaging has been recently demonstrated as a powerful technique for quickly obtaining information about the mechanical properties of a sample. Combining this development with recent gains in imaging speed through small cantilevers holds the promise of a convenient, high-speed method for obtaining nanoscale topography as well as mechanical properties. Nevertheless, instrument bandwidth limitations on cantilever excitation and readout have restricted the ability of multifrequency techniques to fully benefit from small cantilevers. We present an approach for cantilever excitation and deflection readout with a bandwidth of 20 MHz, enabling multifrequency techniques extended beyond 2 MHz for obtaining materials contrast in liquid and air, as well as soft imaging of delicate biological samples.

  5. Insect bite reactions

    Directory of Open Access Journals (Sweden)

    Sanjay Singh

    2013-01-01

    Full Text Available Insects are a class of living creatures within the arthropods. Insect bite reactions are commonly seen in clinical practice. The present review touches upon the medically important insects and their places in the classification, the sparse literature on the epidemiology of insect bites in India, and different variables influencing the susceptibility of an individual to insect bites. Clinical features of mosquito bites, hypersensitivity to mosquito bites Epstein-Barr virus NK (HMB-EBV-NK disease, eruptive pseudoangiomatosis, Skeeter syndrome, papular pruritic eruption of HIV/AIDS, and clinical features produced by bed bugs, Mexican chicken bugs, assassin bugs, kissing bugs, fleas, black flies, Blandford flies, louse flies, tsetse flies, midges, and thrips are discussed. Brief account is presented of the immunogenic components of mosquito and bed bug saliva. Papular urticaria is discussed including its epidemiology, the 5 stages of skin reaction, the SCRATCH principle as an aid in diagnosis, and the recent evidence supporting participation of types I, III, and IV hypersensitivity reactions in its causation is summarized. Recent developments in the treatment of pediculosis capitis including spinosad 0.9% suspension, benzyl alcohol 5% lotion, dimethicone 4% lotion, isopropyl myristate 50% rinse, and other suffocants are discussed within the context of evidence derived from randomized controlled trials and key findings of a recent systematic review. We also touch upon a non-chemical treatment of head lice and the ineffectiveness of egg-loosening products. Knockdown resistance (kdr as the genetic mechanism making the lice nerves insensitive to permethrin is discussed along with the surprising contrary clinical evidence from Europe about efficacy of permethrin in children with head lice carrying kdr-like gene. The review also presents a brief account of insects as vectors of diseases and ends with discussion of prevention of insect bites and some

  6. Marine animal stings or bites

    Science.gov (United States)

    Stings - marine animals; Bites - marine animals ... Things you can do to prevent a marine animal sting or bite include: Swim near a lifeguard. Observe posted signs that may warn of danger from jellyfish or other hazardous marine life. ...

  7. Funnel-web spider bite

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002844.htm Funnel-web spider bite To use the sharing features on ... the effects of a bite from the funnel-web spider. Male funnel-web spiders are more poisonous ...

  8. Evaluación electromiográfica de los músculos masticadores durante la fuerza máxima de mordedura Electromyography evaluations of the masticator muscles during the maximum bite force

    Directory of Open Access Journals (Sweden)

    M.J.P. Coelho-Ferraz

    2008-12-01

    Full Text Available La actividad de los músculos masetero y de la porción anterior temporal de ambos lados, derecho e izquierdo, respectivamente, durante la fuerza máxima de mordedura fue estudiada en voluntarios sanos. El estudio incluyó a 17 voluntarios adultos de ambos sexos, edad promedia de 25 años, que no evidenciaban ningún indicio de disfunción temporomandibular y eran relacionados con la Facultad de Odontología de Piracicaba. Se registraron los datos electromiográficos en ambos lados de la cara del masetero y de la porción anterior de los músculos temporal y suprahioideo en las posiciones postural e isométrica. Se utilizaron electrodos de superficie pasivos para niños, de Ag/AgCl, con forma circular y descargables de Meditrace® Kendall-LTP, modelo Chicopee MA01. Éstos se conectaron a un preamplificador con una ganancia de 20x que formaba un circuito de diferenciales. Se captaron los registros de las señales eléctricas utilizando un equipo EMG-8OOC de EMG System of Brazil, Ltd., de ocho canales, a una frecuencia de 2 KHz con 16 bitios de resolución y un filtro digital con un paso de banda de 20 a 500 Hz. Se utilizó también un transductor de presión que consistía en un tubo de goma con un sensor de presión (MPX 5700* (Motorola SPS, Austin, TX, EE.UU. para registrar la fuerza máxima de mordedura. El análisis estadístico incluyó la correlación lineal, la prueba t emparejada y el análisis de la varianza. Se consideró estadísticamente significativa una probabilidad de pHealthy individuals were examined in terms of the pattern of activity of the masseter and temporal muscles in their anterior portion of both right and left sides, respectively, with the maximum bite force. The study consisted in seventeen adult volunteers with no sign of apparent temporomandibular dysfunction, of both genders, connected to the School of Dentistry of Piracicaba, with average age of 25 years old. The electromyography data were obtained, bilaterally, of

  9. Mosquito Bites are Bad!

    Centers for Disease Control (CDC) Podcasts

    2016-08-11

    In this podcast for kids, the Kidtastics talk about the dangers of mosquito bites and how to prevent getting them.  Created: 8/11/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/11/2016.

  10. Rat bite fever.

    NARCIS (Netherlands)

    Gaastra, W.; Boot, R.G.A.; Ho, H.; Lipman, L.J.A.

    2009-01-01

    Rat bite fever (RBF) is a bacterial zoonosis for which two causal bacterial species have been identified: Streptobacillis moniliformis and Spirillum minus. Haverhill fever (HF) is a form of S. moniliformis infection believed to develop after ingestion of contaminated food or water. Here the

  11. Bug Bites and Stings

    Science.gov (United States)

    ... or sting. Handling Bee and Wasp Stings A bee will usually leave behind a stinger attached to a venom sac. Try to remove it as quickly as ... child has had an allergic reaction to a bee or wasp sting in the past, see your ... shape on its underbelly. The venom (a toxic substance) in a black widow bite ...

  12. High Cable Forces Deteriorate Pinch Force Control in Voluntary-Closing Body-Powered Prostheses.

    Directory of Open Access Journals (Sweden)

    Mona Hichert

    Full Text Available It is generally asserted that reliable and intuitive control of upper-limb prostheses requires adequate feedback of prosthetic finger positions and pinch forces applied to objects. Body-powered prostheses (BPPs provide the user with direct proprioceptive feedback. Currently available BPPs often require high cable operation forces, which complicates control of the forces at the terminal device. The aim of this study is to quantify the influence of high cable forces on object manipulation with voluntary-closing prostheses.Able-bodied male subjects were fitted with a bypass-prosthesis with low and high cable force settings for the prehensor. Subjects were requested to grasp and transfer a collapsible object as fast as they could without dropping or breaking it. The object had a low and a high breaking force setting.Subjects conducted significantly more successful manipulations with the low cable force setting, both for the low (33% more and high (50% object's breaking force. The time to complete the task was not different between settings during successful manipulation trials.High cable forces lead to reduced pinch force control during object manipulation. This implies that low cable operation forces should be a key design requirement for voluntary-closing BPPs.

  13. Factors Associated with Tick Bite Preventive Practices among Farmworkers in Malaysia

    Science.gov (United States)

    Wong, Li Ping; Tay, Sun Tee; Bulgiba, Awang; Zandi, Keivan; Kho, Kai Ling; Koh, Fui Xian; Ong, Bee Lee; Jaafar, Tariq; Hassan Nizam, Quaza Nizamuddin

    2016-01-01

    Background Farmworkers are at high-risk for tick bites, which potentially transmit various tick-borne diseases. Previous studies show that personal prevention against tick bites is key, and certain factors namely, knowledge, experience of tick bites, and health beliefs influence compliance with tick bites preventive behaviour. This study aimed to assess these factors and their associations with tick bite preventive practices among Malaysian farmworkers. Methods A total of eight cattle, goat and sheep farms in six states in Peninsular Malaysia participated in a cross-sectional survey between August and October 2013 Results A total of 151 (72.2%) out of 209 farmworkers answered the questionnaire. More than half of the farmworkers (n = 91) reported an experience of tick bites. Farms with monthly acaricide treatment had significantly (P<0.05) a low report of tick bites. Tick bite exposure rates did not differ significantly among field workers and administrative workers. The mean total knowledge score of ticks for the overall farmworkers was 13.6 (SD±3.2) from 20. The mean total tick bite preventive practices score for all farmworkers was 8.3 (SD±3.1) from 15. Fixed effect model showed the effects of four factors on tick bite prevention: (1) farms, (2) job categories (administrative workers vs. field workers), (3) perceived severity of tick bites, and (4) perceived barriers to tick bite prevention. Conclusions A high proportion of farmworkers, including administrative workers, reported an experience of tick bites. The effectiveness of monthly acaricide treatment was declared by low reports of tick bites on these farms. Tick bite preventive practices were insufficient, particularly in certain farms and for administrative workers. Our findings emphasise the need to have education programmes for all farmworkers and targeting farms with low prevention practices. Education and health programmes should increase the perception of the risk of tick bites and remove perceived

  14. In vitro induction of functional allergen-specific CD4+ CD25high Treg cells in horses affected with insect bite hypersensitivity.

    Science.gov (United States)

    Hamza, E; Akdis, C A; Wagner, B; Steinbach, F; Marti, E

    2013-08-01

    Insect bite hypersensitivity (IBH) is a recurrent allergic dermatitis of horses with similarities to human atopic eczema, caused by bites of insects of the genus Culicoides. Previous studies suggested a dysregulated T cell tolerance to Culicoides allergen in IBH-affected horses. We have investigated whether the suppressive function of CD4(+) CD25(high) cells is impaired in IBH-affected horses and possible ways to restore it. CD4(+) CD25(-) cells sorted from peripheral blood mononuclear cells (PBMC) were stimulated with irradiated autologous PBMC pulsed with Culicoides or tetanus toxoid as control antigen, in the presence of CD4(+) CD25(high) cells. Furthermore, Culicoides-specific CD4(+) CD25(high) regulatory cells were expanded or induced from CD4(+) CD25(-) cells in vitro in the presence of a combination of rIL-2 and rTGF-β1 (rIL-2/rTGF-β1) or of retinoic acid and rapamycin (RetA/Rapa). Proliferation was determined by [(3) H] thymidine incorporation and cytokine production measured by flow cytometry. The ability of Culicoides- but not tetanus-stimulated CD4(+) CD25(high) cells to suppress proliferation of CD4(+) CD25(-) cells was significantly lower in IBH-affected horses (28%) than in healthy controls (86%). The decreased suppression in IBH-affected horses was associated with a significantly higher proportion of IL-4(+) cells and a lower percentage of FoxP3(+) IL-10(+) compared to controls. Addition of rIL-2/rTGF-β1 or of RetA/Rapa to Culicoides-stimulated CD4(+) CD25(high) cells from IBH-affected horses significantly increased the proportion of FoxP3(+) IL-10(+) cells. We also found that RetA/Rapa induced a more significant decrease in the frequency of IL-4(+) cells than rIL-2/rTGF-β1. Moreover, the suppressive activity of Culicoides-stimulated CD4(+) CD25(high) cells was significantly restored by both rIL-2/rTGF-β1and RetA/Rapa, albeit in an antigen-unspecific manner. In contrast, in vitro induced Culicoides-specific CD4(+) CD25(high) cells suppressed

  15. High-speed force mapping on living cells with a small cantilever atomic force microscope

    International Nuclear Information System (INIS)

    Braunsmann, Christoph; Seifert, Jan; Rheinlaender, Johannes; Schäffer, Tilman E.

    2014-01-01

    The imaging speed of the wide-spread force mapping mode for quantitative mechanical measurements on soft samples in liquid with the atomic force microscope (AFM) is limited by the bandwidth of the z-scanner and viscous drag forces on the cantilever. Here, we applied high-speed, large scan-range atomic force microscopy and small cantilevers to increase the speed of force mapping by ≈10−100 times. This allowed resolving dynamic processes on living mouse embryonic fibroblasts. Cytoskeleton reorganization during cell locomotion, growth of individual cytoskeleton fibers, cell blebbing, and the formation of endocytic pits in the cell membrane were observed. Increasing the force curve rate from 2 to 300 Hz increased the measured apparent Young's modulus of the cells by about 10 times, which facilitated force mapping measurements at high speed

  16. High-speed force mapping on living cells with a small cantilever atomic force microscope

    Energy Technology Data Exchange (ETDEWEB)

    Braunsmann, Christoph; Seifert, Jan; Rheinlaender, Johannes; Schäffer, Tilman E., E-mail: Tilman.Schaeffer@uni-tuebingen [Institute of Applied Physics and LISA, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen (Germany)

    2014-07-15

    The imaging speed of the wide-spread force mapping mode for quantitative mechanical measurements on soft samples in liquid with the atomic force microscope (AFM) is limited by the bandwidth of the z-scanner and viscous drag forces on the cantilever. Here, we applied high-speed, large scan-range atomic force microscopy and small cantilevers to increase the speed of force mapping by ≈10−100 times. This allowed resolving dynamic processes on living mouse embryonic fibroblasts. Cytoskeleton reorganization during cell locomotion, growth of individual cytoskeleton fibers, cell blebbing, and the formation of endocytic pits in the cell membrane were observed. Increasing the force curve rate from 2 to 300 Hz increased the measured apparent Young's modulus of the cells by about 10 times, which facilitated force mapping measurements at high speed.

  17. Can NATO's new Very High Readiness Joint Task Force deter?

    DEFF Research Database (Denmark)

    Rynning, Sten; Ringsmose, Jens

    2017-01-01

    ” a distinct strategic rival – Russia. Chief among the Welsh summit initiatives was the decision to set up a new multinational spearhead force – the Very High Readiness Joint Task Force (VJTF) – as part of an enhanced NATO Response Force (NRF) and within the framework of a so-called Readiness Action Plan (RAP...

  18. Stable dynamics in forced systems with sufficiently high/low forcing frequency.

    Science.gov (United States)

    Bartuccelli, M; Gentile, G; Wright, J A

    2016-08-01

    We consider parametrically forced Hamiltonian systems with one-and-a-half degrees of freedom and study the stability of the dynamics when the frequency of the forcing is relatively high or low. We show that, provided the frequency is sufficiently high, Kolmogorov-Arnold-Moser (KAM) theorem may be applied even when the forcing amplitude is far away from the perturbation regime. A similar result is obtained for sufficiently low frequency, but in that case we need the amplitude of the forcing to be not too large; however, we are still able to consider amplitudes which are outside of the perturbation regime. In addition, we find numerically that the dynamics may be stable even when the forcing amplitude is very large, well beyond the range of validity of the analytical results, provided the frequency of the forcing is taken correspondingly low.

  19. Imaging stability in force-feedback high-speed atomic force microscopy

    International Nuclear Information System (INIS)

    Kim, Byung I.; Boehm, Ryan D.

    2013-01-01

    We studied the stability of force-feedback high-speed atomic force microscopy (HSAFM) by imaging soft, hard, and biological sample surfaces at various applied forces. The HSAFM images showed sudden topographic variations of streaky fringes with a negative applied force when collected on a soft hydrocarbon film grown on a grating sample, whereas they showed stable topographic features with positive applied forces. The instability of HSAFM images with the negative applied force was explained by the transition between contact and noncontact regimes in the force–distance curve. When the grating surface was cleaned, and thus hydrophilic by removing the hydrocarbon film, enhanced imaging stability was observed at both positive and negative applied forces. The higher adhesive interaction between the tip and the surface explains the improved imaging stability. The effects of imaging rate on the imaging stability were tested on an even softer adhesive Escherichia coli biofilm deposited onto the grating structure. The biofilm and planktonic cell structures in HSAFM images were reproducible within the force deviation less than ∼0.5 nN at the imaging rate up to 0.2 s per frame, suggesting that the force-feedback HSAFM was stable for various imaging speeds in imaging softer adhesive biological samples. - Highlights: ► We investigated the imaging stability of force-feedback HSAFM. ► Stable–unstable imaging transitions rely on applied force and sample hydrophilicity. ► The stable–unstable transitions are found to be independent of imaging rate

  20. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... your fingers and from your nails to your face and mouth. To help you stop biting your ... re inclined to bite may help solve the problem. Try to gradually stop biting your nails: Some ...

  1. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... skin, hair, and nails Skin dictionary Camp Discovery Good Skin Knowledge lesson plans and activities Video library ... biting. Replace the nail-biting habit with a good habit: When you feel like biting your nails, ...

  2. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... this safe, but awful-tasting formula discourages many people from biting their nails. Get regular manicures: Spending ... longer bite any of your nails. For some people, nail biting may be a sign of a ...

  3. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... biting can make the skin around your nails feel sore, and it can damage the tissue that ... biting habit with a good habit: When you feel like biting your nails, try playing with a ...

  4. Morphology of open bite.

    Science.gov (United States)

    Krey, Karl-Friedrich; Dannhauer, Karl-Heinz; Hierl, Thomas

    2015-05-01

    The purpose of this work was to define and illustrate the skeletal morphology of open-bite patients against the background of sagittal jaw relationships on the basis of lateral cephalograms. Lateral cephalograms of 197 untreated adults were analyzed in dental imaging software (Onyx Ceph 3™; Image Instruments, Chemnitz, Germany). Four groups were formed based on vertical (Index scores) and sagittal (individualized ANB values) parameters. Ninety-nine patients were defined as the control group due to their neutral sagittal and vertical relationships. The remaining patients were found by their vertical relationships to represent open-bite cases and were divided by their sagittal relationships into three study groups: neutral (Class I, n = 34), distal (Class II, n = 26), and mesial (Class III, n = 38). A geometric morphometric approach was used to analyze the x,y-coordinates of 28 skeletal landmarks on each cephalogram. Relative size was captured based on centroid size (CS). The shape-determining factors in the groups were compared by permutation testing after Procrustes transformation, and intergroup differences were visualized in the form of thin-plate splines. While size (CS) was significantly increased in the Class III group, the other two groups were not different from the control group. After Procrustes transformation, characteristic and invariably significant (p common that the mandibular ramus is compressed, but marked differences are seen in terms of vertical development of the maxilla. This differentiated view of open-bite cases should be taken into consideration during individual etiology assessment and treatment planning.

  5. Small-scale field evaluation of push-pull system against early- and outdoor-biting malaria mosquitoes in an area of high pyrethroid resistance in Tanzania [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Arnold S. Mmbando

    2017-11-01

    Full Text Available Background: Despite high coverage of indoor interventions like insecticide-treated nets, mosquito-borne infections persist, partly because of outdoor-biting, early-biting and insecticide-resistant vectors. Push-pull systems, where mosquitoes are repelled from humans and attracted to nearby lethal targets, may constitute effective complementary interventions. Methods: A partially randomized cross-over design was used to test efficacy of push-pull in four experimental huts and four local houses, in an area with high pyrethroid resistance in Tanzania. The push-pull system consisted of 1.1% or 2.2% w/v transfluthrin repellent dispensers and an outdoor lure-and-kill device (odour-baited mosquito landing box. Matching controls were set up without push-pull. Adult male volunteers collected mosquitoes attempting to bite them outdoors, but collections were also done indoors using exit traps in experimental huts and by volunteers in the local houses. The collections were done hourly (1830hrs-0730hrs and mosquito catches compared between push-pull and controls. An. gambiae s.l. and An. funestus s.l. were assessed by PCR to identify sibling species, and ELISA to detect Plasmodium falciparum and blood meal sources. Results: Push-pull in experimental huts reduced outdoor-biting for An. arabiensis and Mansonia species by 30% and 41.5% respectively. However, the reductions were marginal and insignificant for An. funestus (12.2%; p>0.05 and Culex (5%; p>0.05. Highest protection against all species occurred before 2200hrs. There was no significant difference in number of mosquitoes inside exit traps in huts with or without push-pull. In local households, push-pull significantly reduced indoor and outdoor-biting of An. arabiensis by 48% and 25% respectively, but had no effect on other species. Conclusion: This push-pull system offered modest protection against outdoor-biting An. arabiensis, without increasing indoor mosquito densities. Additional experimentation

  6. Pigeon tick bite

    DEFF Research Database (Denmark)

    Rolla, G; Heffler, E; Boita, M

    2018-01-01

    Anaphylaxis is a serious systemic allergic reaction with rapid onset and potentially life-threatening. We report in detail a case of severe nocturnal anaphylaxis due to pigeon tick bite showing the diagnostic value of the extract and the recombinant allergen in the diagnostic procedures (basophil...... reagents. Because of the growing number of pigeons in Middle and Southern Europe cities, some cases of idiopathic anaphylaxis could potentially be caused by A. reflexus in those countries. The identification of pigeon ticks as a trigger of anaphylaxis would greatly improve medical care and advice...

  7. Biting back: BiTE antibodies as a promising therapy for acute myeloid leukemia.

    Science.gov (United States)

    Walter, Roland B

    2014-06-01

    The experience with gemtuzumab ozogamicin has highlighted both the potential value and limitations of antibodies in acute myeloid leukemia (AML). Recently, bispecific T-cell engager (BiTE) antibodies have emerged as a means to harness polyclonal cytotoxic T-cells and cause highly efficient lysis of targeted tumor cells. Promising early results have been obtained with the CD19-directed BiTE antibody, blinatumomab, in patients with acute lymphoblastic leukemia. A first candidate for AML is the CD33/CD3 molecule, AMG 330, for which several recent preclinical studies demonstrated high potency and efficacy in destroying CD33(+) human AML cells. Many questions remain to be addressed, but BiTE antibodies may offer an exciting new tool in a disease for which the outcomes in many patients remain unsatisfactory.

  8. Esthetic correction in open bite

    Directory of Open Access Journals (Sweden)

    Swapnil Parlani

    2011-01-01

    Full Text Available Deleterious oral habits, which are persistent, can lead to poor esthetics of a beautiful face. Conventional treatment modalities for an open bite usually include orthodontic treatment and/or skeletal surgery. This article focuses on a different treatment modality for an anterior open bite.

  9. Maximal bite force in young adults with temporomandibular disorders and bruxism Força de mordida máxima em adultos jovens com disfunção temporomandibular e bruxismo

    Directory of Open Access Journals (Sweden)

    Raquel Aparecida Pizolato

    2007-09-01

    Full Text Available Parafunctional habits, such as bruxism, are contributory factors for temporomandibular disorders (TMD. The aim of this study was to evaluate the maximal bite force (MBF in the presence of TMD and bruxism (TMDB in young adults. Twelve women (mean age 21.5 years and 7 men (mean age 22.4 years, composed the TMDB group. Ten healthy women and 9 men (mean age 21.4 and 22.4 years, respectively formed the control group. TMD symptoms were evaluated by a structured questionnaire and clinical signs/symptoms were evaluated during clinical examination. A visual analogical scale (VAS was applied for stress assessment. MBF was measured with a gnatodynamometer. The subjects were asked to bite 2 times with maximal effort, during 5 seconds, with a rest interval of about one minute. The highest values were considered. The data were analyzed with Shapiro-Wilks W-test, descriptive statistics, paired or unpaired t tests or Mann-Whitney tests when indicated, and Fisher's exact test (p Hábitos parafuncionais, como o bruxismo, podem contribuir para a disfunção temporomandibular (DTM. O objetivo deste trabalho foi avaliar a força de mordida máxima (FMM na presença de DTM e bruxismo (DTMB em adultos jovens. Doze mulheres (idade média de 21,5 anos e sete homens (idade média 22,4 anos compuseram o grupo DTMB. O grupo controle foi formado por 10 mulheres e 9 homens saudáveis, com idades médias de 21,4 e 22,4 anos, respectivamente. Os sintomas de DTM foram avaliados com um questionário estruturado, e os sinais/sintomas clínicos foram avaliados no exame clínico. Para avaliar estresse, utilizou-se a escala analógica visual (VAS. A FMM foi mensurada com gnatodinamômetro, e o participante foi orientado a morder com o máximo esforço durante 5 segundos, duas vezes, com intervalo de aproximadamente 1 minuto, considerando-se os valores máximos. Os dados foram analisados pelo teste de Shapiro-Wilks, estatística descritiva, teste t pareado e independente, Mann

  10. Understanding gastric forces calculated from high-resolution pill tracking.

    Science.gov (United States)

    Laulicht, Bryan; Tripathi, Anubhav; Schlageter, Vincent; Kucera, Pavel; Mathiowitz, Edith

    2010-05-04

    Although other methods exist for monitoring gastrointestinal motility and contractility, this study exclusively provides direct and quantitative measurements of the forces experienced by an orally ingested pill. We report motive forces and torques calculated from real-time, in vivo measurements of the movement of a magnetic pill in the stomachs of fasted and fed humans. Three-dimensional net force and two-dimensional net torque vectors as a function of time data during gastric residence are evaluated using instantaneous translational and rotational position data. Additionally, the net force calculations described can be applied to high-resolution pill tracking acquired by any modality. The fraction of time pills experience ranges of forces and torques are analyzed and correlate with the physiological phases of gastric digestion. We also report the maximum forces and torques experienced in vivo by pills as a quantitative measure of the amount of force pills experience during the muscular contractions leading to gastric emptying. Results calculated from human data are compared with small and large animal models with a translational research focus. The reported magnitude and direction of gastric forces experienced by pills in healthy stomachs serves as a baseline for comparison with pathophysiological states. Of clinical significance, the directionality associated with force vector data may be useful in determining the muscle groups associated with gastrointestinal dysmotility. Additionally, the quantitative comparison between human and animal models improves insight into comparative gastric contractility that will aid rational pill design and provide a quantitative framework for interpreting gastroretentive oral formulation test results.

  11. Task force for integral test of High Energy nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-11-01

    According to completion of the JENDL-High Energy file for neutron nuclear cross sections up to 50 MeV, a task force for integral test of high energy nuclear data was organized to discuss a guide line for integral test activities. A status of existing differential and integral experiments and how to perform such a test were discussed in the task force. Here the purpose and outline of the task force is explained with some future problems raised in discussion among the task member. (author)

  12. Shrieking, Biting, and Licking

    Directory of Open Access Journals (Sweden)

    Sarah Stang

    2018-01-01

    Full Text Available This article examines examples of the monstrous-feminine in the form of abject female monsters in a selection of critically acclaimed and commercially successful video games. Various female monsters from CD Projekt RED’s The Witcher series (2007-2015, and Santa Monica Studio’s God of War series (2005-2013 are considered as examples of the abject monstrous-feminine which fall into a long tradition in horror media of making the female body and body movements into something horrific and repulsive. These female monsters use shrieking, biting, licking, and spreading disease as weapons against the male protagonist, who must slay them to restore symbolic order and progress in the games.

  13. [Comparison of bite marks and teeth features using 2D and 3D methods].

    Science.gov (United States)

    Lorkiewicz-Muszyńska, Dorota; Glapiński, Mariusz; Zaba, Czesław; Łabecka, Marzena

    2011-01-01

    The nature of bite marks is complex. They are found at the scene of crime on different materials and surfaces - not only on human body and corpse, but also on food products and material objects. Human bites on skin are sometimes difficult to interpret and to analyze because of the specific character of skin--elastic and distortable--and because different areas of human body have different surfaces and curvatures. A bite mark left at the scene of crime can be a highly helpful way to lead investigators to criminals. The study was performed to establish: 1) whether bite marks exhibit variations in the accuracy of impressions on different materials, 2) whether it is possible to use the 3D method in the process of identifying an individual based on the comparison of bite marks revealed at the scene, and 3D scans of dental casts, 3) whether application of the 3D method allows for elimination of secondary photographic distortion of bite marks. The authors carried out experiments on simulated cases. Five volunteers bit various materials with different surfaces. Experimental bite marks were collected with emphasis on differentiations of materials. Subsequently, dental impressions were taken from five volunteers in order to prepare five sets of dental casts (the maxilla and mandible. The biting edges of teeth were impressed in wax to create an imprint. The samples of dental casts, corresponding wax bite impressions and bite marks from different materials were scanned with 2D and 3D scanners and photographs were taken. All of these were examined in detail and then compared using different methods (2D and 3D). 1) Bite marks exhibit variations in accuracy of impression on different materials. The most legible reproduction of bite marks was seen on cheese. 2) In comparison of bite marks, the 3D method and 3D scans of dental casts are highly accurate. 3) The 3D method helps to eliminate secondary photographic distortion of bite marks.

  14. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... gloves to prevent biting. Replace the nail-biting habit with a good habit: When you feel like biting your nails, try ... recommend taking a gradual approach to break the habit. Try to stop biting one set of nails, ...

  15. Mouthguard BITES (behavior, impulsivity, theory evaluation study): what drives mouthguard use among high school basketball and baseball/softball athletes.

    Science.gov (United States)

    Collins, Christy L; McKenzie, Lara B; Roberts, Kristin J; Fields, Sarah K; Comstock, R Dawn

    2015-10-01

    Although mouthguards are effective, inexpensive, easy to use, and readily available, this form of protective equipment has been underutilized. "Impulsive delay discounting" (an index of impulsive behavior) among high school athletes may help explain their decision making regarding use of protective equipment such as mouthguards. We investigated the relationship between high school baseball, softball, and basketball players' mouthguard use, impulsive delay discounting, and the precaution adoption process model (a behavior change theory). A convenience sample of boys' and girls' basketball and baseball/softball players at 21 high schools in the Greater Columbus, Ohio, metro area completed a self-administered survey that captured their demographic information, knowledge, attitudes, and beliefs regarding mouthguard use, impulsive delay discounting, and precaution adoption process model stage. We surveyed a total of 1636 students (55.9 % male, 43.8 % female, 0.3 % unknown). Only 12.3 % reported using a mouthguard either every time or sometimes during practice or competition. The primary reasons reported for not wearing mouthguards were they were not required to (65.3 %) and that the athletes could not breathe or talk while wearing one (61.5 %). These reasons were consistent across sex and sport. Most athletes reported that their coaches (87.3 %) and parents (64.5 %) had never talked to them about wearing a mouthguard. Lower precaution adoption process model stage was significantly associated with higher impulsivity (p softball remains low despite the risk of dental injury in these sports. Effective, evidence-based, targeted, and tailored interventions to improve adolescent athletes' use of mouthguards to prevent sports-related dental injuries should be based on the specific behavioral and social factors influencing each athlete's decision making regarding use of mouthguards.

  16. Another one bites the dust: faecal silica levels in large herbivores correlate with high-crowned teeth

    Science.gov (United States)

    Hummel, Jürgen; Findeisen, Eva; Südekum, Karl-Heinz; Ruf, Irina; Kaiser, Thomas M.; Bucher, Martin; Clauss, Marcus; Codron, Daryl

    2011-01-01

    The circumstances of the evolution of hypsodonty (= high-crowned teeth) are a bone of contention. Hypsodonty is usually linked to diet abrasiveness, either from siliceous phytoliths (monocotyledons) or from grit (dusty environments). However, any empirical quantitative approach testing the relation of ingested silica and hypsodonty is lacking. In this study, faecal silica content was quantified as acid detergent insoluble ash and used as proxy for silica ingested by large African herbivores of different digestive types, feeding strategies and hypsodonty levels. Separate sample sets were used for the dry (n = 15 species) and wet (n = 13 species) season. Average faecal silica contents were 17–46 g kg−1 dry matter (DM) for browsing and 52–163 g kg−1 DM for grazing herbivores. No difference was detected between the wet (97.5 ± 14.4 g kg−1 DM) and dry season (93.5 ± 13.7 g kg−1 DM) faecal silica. In a phylogenetically controlled analysis, a strong positive correlation (dry season r = 0.80, p < 0.0005; wet season r = 0.74, p < 0.005) was found between hypsodonty index and faecal silica levels. While surprisingly our results do not indicate major seasonal changes in silica ingested, the correlation of faecal silica and hypsodonty supports a scenario of a dominant role of abrasive silica in the evolution of high-crowned teeth. PMID:21068036

  17. Reliability of force-velocity relationships during deadlift high pull.

    Science.gov (United States)

    Lu, Wei; Boyas, Sébastien; Jubeau, Marc; Rahmani, Abderrahmane

    2017-11-13

    This study aimed to evaluate the within- and between-session reliability of force, velocity and power performances and to assess the force-velocity relationship during the deadlift high pull (DHP). Nine participants performed two identical sessions of DHP with loads ranging from 30 to 70% of body mass. The force was measured by a force plate under the participants' feet. The velocity of the 'body + lifted mass' system was calculated by integrating the acceleration and the power was calculated as the product of force and velocity. The force-velocity relationships were obtained from linear regression of both mean and peak values of force and velocity. The within- and between-session reliability was evaluated by using coefficients of variation (CV) and intraclass correlation coefficients (ICC). Results showed that DHP force-velocity relationships were significantly linear (R² > 0.90, p  0.94), mean and peak velocities showed a good agreement (CV reliable and can therefore be utilised as a tool to characterise individuals' muscular profiles.

  18. Can NATO's new very high readiness joint task force deter?

    DEFF Research Database (Denmark)

    Rynning, Sten; Ringsmose, Jens

    2017-01-01

    When NATO-allies met at their Wales summit in September 2014, the D-word was back in vogue. Not in a muttering, shy or implicit way, but unambiguously and straightforward. For the first time in more than two decades NATO’s heads of states and governments openly discussed how best to “deter......” a distinct strategic rival – Russia. Chief among the Welsh summit initiatives was the decision to set up a new multinational spearhead force – the Very High Readiness Joint Task Force (VJTF) – as part of an enhanced NATO Response Force (NRF) and within the framework of a so-called Readiness Action Plan (RAP...

  19. Identifying Insect Bites and Stings

    Science.gov (United States)

    ... Editor & Contributors Sponsors Sponsorship Opportunities Spread the Word Shop AAP Find a Pediatrician Health Issues Conditions Abdominal ... birdbaths) and are attracted by bright colors and sweat. Bites result in stinging sensation followed by a ...

  20. Tips to Prevent Mosquito Bites

    Science.gov (United States)

    ... discourage mosquitoes, ticks and other biting insects from landing on you. Here are tips for other preventive ... CDC Mosquito Control Methods - NPIC Exit Top of Page Contact Us to ask a question, provide feedback, ...

  1. Rat-bite fever presenting with rash and septic arthritis.

    Science.gov (United States)

    Kanechorn Na Ayuthaya, Rajyani; Niumpradit, Nucha

    2005-11-01

    Rat-bite fever is an uncommon disease known for its endemicity to occur worldwide. Although most patients tend to develop mild symptoms with improvement from conventional antibiotics, it can progress with severe complications with a mortality rate as high as 13% without proper treatment. The authors report a complicated case of rat bite-fever involving a 61-year old woman who presented with fever petechial rash, and septic arthritis following a rat bite. Initially, multiple antibiotics were administered but were not effective. As a consequence, invasive procedures such as arthrotomy and joint debridement were done and prolonged antibiotic was administered until clinical resolution. Since many cases do not have a history of rat bite and may present with fever, rashes, and arthritis it is essential to distinguish it from other diseases. Here, the authors will provide details on the etiology, clinical manifestations, diagnosis, and management to aid prompt detection and treatment of the disease.

  2. The FORCE: A highly portable parallel programming language

    Science.gov (United States)

    Jordan, Harry F.; Benten, Muhammad S.; Alaghband, Gita; Jakob, Ruediger

    1989-01-01

    Here, it is explained why the FORCE parallel programming language is easily portable among six different shared-memory microprocessors, and how a two-level macro preprocessor makes it possible to hide low level machine dependencies and to build machine-independent high level constructs on top of them. These FORCE constructs make it possible to write portable parallel programs largely independent of the number of processes and the specific shared memory multiprocessor executing them.

  3. The FORCE - A highly portable parallel programming language

    Science.gov (United States)

    Jordan, Harry F.; Benten, Muhammad S.; Alaghband, Gita; Jakob, Ruediger

    1989-01-01

    This paper explains why the FORCE parallel programming language is easily portable among six different shared-memory multiprocessors, and how a two-level macro preprocessor makes it possible to hide low-level machine dependencies and to build machine-independent high-level constructs on top of them. These FORCE constructs make it possible to write portable parallel programs largely independent of the number of processes and the specific shared-memory multiprocessor executing them.

  4. Mechanics of biting in great white and sandtiger sharks.

    Science.gov (United States)

    Ferrara, T L; Clausen, P; Huber, D R; McHenry, C R; Peddemors, V; Wroe, S

    2011-02-03

    Although a strong correlation between jaw mechanics and prey selection has been demonstrated in bony fishes (Osteichthyes), how jaw mechanics influence feeding performance in cartilaginous fishes (Chondrichthyes) remains unknown. Hence, tooth shape has been regarded as a primary predictor of feeding behavior in sharks. Here we apply Finite Element Analysis (FEA) to examine form and function in the jaws of two threatened shark species, the great white (Carcharodon carcharias) and the sandtiger (Carcharias taurus). These species possess characteristic tooth shapes believed to reflect dietary preferences. We show that the jaws of sandtigers and great whites are adapted for rapid closure and generation of maximum bite force, respectively, and that these functional differences are consistent with diet and dentition. Our results suggest that in both taxa, insertion of jaw adductor muscles on a central tendon functions to straighten and sustain muscle fibers to nearly orthogonal insertion angles as the mouth opens. We argue that this jaw muscle arrangement allows high bite forces to be maintained across a wider range of gape angles than observed in mammalian models. Finally, our data suggest that the jaws of sub-adult great whites are mechanically vulnerable when handling large prey. In addition to ontogenetic changes in dentition, further mineralization of the jaws may be required to effectively feed on marine mammals. Our study is the first comparative FEA of the jaws for any fish species. Results highlight the potential of FEA for testing previously intractable questions regarding feeding mechanisms in sharks and other vertebrates. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Extract of the seeds of the plant Vitex agnus castus proven to be highly efficacious as a repellent against ticks, fleas, mosquitoes and biting flies.

    Science.gov (United States)

    Mehlhorn, Heinz; Schmahl, Günter; Schmidt, Jürgen

    2005-03-01

    About 70 plant extracts were tested for their ability to repel the attacks of blood-sucking arthropods. It was found that a CO2 extract of the seeds of the Mediterranean plant Vitex agnus castus (monk's pepper) can be used as a spray to keep away especially Ixodes ricinus and Rhipicephalus sanguineus ticks from animals and humans for at least 6 h. In addition mosquitoes, biting flies and fleas are also repelled for about 6 h.

  6. The management of animal bites in the United kingdom.

    Science.gov (United States)

    Evgeniou, E; Markeson, D; Iyer, S; Armstrong, A

    2013-01-01

    Animal bites represent a significant global health issue. The evidence in the literature regarding their management in many areas is conflicting and unclear. This project attempts to identify current evidence in the literature on the management of animal bites and assess if current practice in the United Kingdom is evidence based. A literature review on the management of animal bites was performed, and a national UK survey was contacted using a questionnaire based on the available evidence in the literature. The results from this survey show that 98% of plastic surgery units routinely use prophylactic antibiotics in all animal bite wounds; 58% close low-risk injuries primarily after initial washout, and there are conflicting opinions regarding the management of associated fractures and soft tissue injuries. The available data in the literature suggest that appropriate wound management is the most important factor for prevention of infection in animal bites. Antibiotic prophylaxis should only be given in high-risk wounds and primary closure should be performed in low-risk wounds. The management protocols of many plastic surgery units often diverge from the available evidence within the literature. On the basis of a thorough literature review, a guideline for the management of animal bites is presented. Future studies should investigate the management of associated fractures and soft tissue injuries.

  7. High-bandwidth piezoresistive force probes with integrated thermal actuation

    International Nuclear Information System (INIS)

    Doll, Joseph C; Pruitt, Beth L

    2012-01-01

    We present high-speed force probes with on-chip actuation and sensing for the measurement of pN-scale forces at the microsecond timescale. We achieve a high resonant frequency in water (1–100 kHz) with requisite low spring constants (0.3–40 pN nm −1 ) and low integrated force noise (1–100 pN) by targeting probe dimensions on the order of 300 nm thick, 1–2 μm wide and 30–200 μm long. Forces are measured using silicon piezoresistors, while the probes are actuated thermally with an aluminum unimorph and silicon heater. The piezoresistive sensors are designed using the open-source numerical optimization code that incorporates constraints on operating temperature. Parylene passivation enables operation in ionic media and we demonstrate simultaneous actuation and sensing. The improved design and fabrication techniques that we describe enable a 10–20-fold improvement in force resolution or measurement bandwidth over prior piezoresistive cantilevers of comparable thickness. (paper)

  8. High bandwidth piezoresistive force probes with integrated thermal actuation

    Science.gov (United States)

    Doll, Joseph C.; Pruitt, Beth L.

    2012-01-01

    We present high-speed force probes with on-chip actuation and sensing for the measurement of pN-scale forces at the microsecond time scale. We achieve a high resonant frequency in water (1–100 kHz) with requisite low spring constants (0.3–40 pN/nm) and low integrated force noise (1–100 pN) by targeting probe dimensions on the order of 300 nm thick, 1–2 μm wide and 30–200 μm long. Forces are measured using silicon piezoresistors while the probes are actuated thermally with an aluminum unimorph and silicon heater. The piezoresistive sensors are designed using open source numerical optimization code that incorporates constraints on operating temperature. Parylene passivation enables operation in ionic media and we demonstrate simultaneous actuation and sensing. The improved design and fabrication techniques that we describe enable a 10–20 fold improvement in force resolution or measurement bandwidth over prior piezoresistive cantilevers of comparable thickness. PMID:23175616

  9. Força de mordida em crianças com mantenedor de espaço funcional na fase da dentadura mista inicial Bite force in children with functional space maintainer in early mixed dentition

    Directory of Open Access Journals (Sweden)

    Suzane Rodrigues Jacinto-Gonçalves

    2009-08-01

    Full Text Available OBJETIVO: verificar a influência do mantenedor de espaço funcional (MEF na força muscular em crianças com perda prematura de molares decíduos na fase inicial da dentadura mista (5,5 a 6,5 anos de idade com oclusão normal, considerando-se o padrão facial. MÉTODOS: a amostra foi constituída por dois grupos: Grupo MEF (n = 15, com perda precoce de pelo menos um molar decíduo; e Grupo Controle (n = 16. Determinou-se a força de mordida máxima (FM com um tubo transmissor pressurizado, conectado a um circuito eletrônico analógico/digital antes (t0, um mês (t1 e 6 meses (t6 após a instalação do mantenedor. O padrão facial foi determinado pelo índice de Jarabak (FHR. Os dados foram analisados pela estatística descritiva, análise de variância para medidas repetidas, teste t e correlação de Pearson. RESULTADOS:a FM foi significativamente menor em t0 e t1 para o Grupo MEF em relação ao Controle. Em t6 não houve diferença. Os dois grupos apresentaram a FM significativamente maior em t6, em relação a t0, mas o percentual de variação para o Grupo MEF foi significativamente maior. Os valores de FHR não se correlacionaram com a FM, não ocorrendo diferença entre os tipos faciais intragrupos. Os dolicofaciais do Grupo MEF apresentaram a FM significativamente menor que os do Grupo Controle, em t0 e t1, mas não em t6. CONCLUSÃO: o maior aumento na FM para o Grupo MEF após 6 meses foi favorecido pelo maior número de contatos oclusais, devido aos dentes artificiais, melhorando a função e recuperando a força muscular.AIM: To verify the influence of a functional space maintainer (FSM in muscle strength in children with premature loss of primary molars in early mixed dentition (5.5-6.5 years old with normal occlusion, considering the facial pattern. METHODS: The sample was distributed in: FSM Group (n = 15, with premature loss of at least one primary molar and a Control Group (n = 16. It was determined the maximal bite force (BF

  10. Cutting force model for high speed machining process

    International Nuclear Information System (INIS)

    Haber, R. E.; Jimenez, J. E.; Jimenez, A.; Lopez-Coronado, J.

    2004-01-01

    This paper presents cutting force-based models able to describe a high speed machining process. The model considers the cutting force as output variable, essential for the physical processes that are taking place in high speed machining. Moreover, this paper shows the mathematical development to derive the integral-differential equations, and the algorithms implemented in MATLAB to predict the cutting force in real time MATLAB is a software tool for doing numerical computations with matrices and vectors. It can also display information graphically and includes many toolboxes for several research and applications areas. Two end mill shapes are considered (i. e. cylindrical and ball end mill) for real-time implementation of the developed algorithms. the developed models are validated in slot milling operations. The results corroborate the importance of the cutting force variable for predicting tool wear in high speed machining operations. The developed models are the starting point for future work related with vibration analysis, process stability and dimensional surface finish in high speed machining processes. (Author) 19 refs

  11. The biting performance of Homo sapiens and Homo heidelbergensis.

    Science.gov (United States)

    Godinho, Ricardo Miguel; Fitton, Laura C; Toro-Ibacache, Viviana; Stringer, Chris B; Lacruz, Rodrigo S; Bromage, Timothy G; O'Higgins, Paul

    2018-05-01

    Modern humans have smaller faces relative to Middle and Late Pleistocene members of the genus Homo. While facial reduction and differences in shape have been shown to increase biting efficiency in Homo sapiens relative to these hominins, facial size reduction has also been said to decrease our ability to resist masticatory loads. This study compares crania of Homo heidelbergensis and H. sapiens with respect to mechanical advantages of masticatory muscles, force production efficiency, strains experienced by the cranium and modes of deformation during simulated biting. Analyses utilize X-ray computed tomography (CT) scan-based 3D models of a recent modern human and two H. heidelbergensis. While having muscles of similar cross-sectional area to H. heidelbergensis, our results confirm that the modern human masticatory system is more efficient at converting muscle forces into bite forces. Thus, it can produce higher bite forces than Broken Hill for equal muscle input forces. This difference is the result of alterations in relative in and out-lever arm lengths associated with well-known differences in midfacial prognathism. Apparently at odds with this increased efficiency is the finding that the modern human cranium deforms more, resulting in greater strain magnitudes than Broken Hill when biting at the equivalent tooth. Hence, the facial reduction that characterizes modern humans may not have evolved as a result of selection for force production efficiency. These findings provide further evidence for a degree of uncoupling between form and function in the masticatory system of modern humans. This may reflect the impact of food preparation technologies. These data also support previous suggestions that differences in bite force production efficiency can be considered a spandrel, primarily driven by the midfacial reduction in H. sapiens that occurred for other reasons. Midfacial reduction plausibly resulted in a number of other significant changes in morphology, such

  12. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous ... one’s greatest efforts, bug bites still happen. Fortunately, most bug bites and stings can be safely treated ...

  13. Injurious tail biting in pigs

    DEFF Research Database (Denmark)

    D'Eath, R.B.; Amott, G.; Turner, S. P.

    2014-01-01

    not allow tail docking at all. Against this background, using a novel approach focusing on research where tail injuries were quantified, we review the measures that can be used to control tail biting in pigs without tail docking. Using this strict criterion, there was good evidence that manipulable...... substrates and feeder space affect damaging tail biting. Only epidemiological evidence was available for effects of temperature and season, and the effect of stocking density was unclear. Studies suggest that group size has little effect, and the effects of nutrition, disease and breed require further...... underlying processes of tail biting. A quantitative comparison of the efficacy of different methods of provision of manipulable materials, and a review of current practices in countries and assurance schemes where tail docking is banned, both suggest that daily provision of small quantities of destructible...

  14. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... nails, or even an entire hand. The goal is to get to the point where you no longer bite any of your nails. For some people, nail biting may be a sign of a more serious psychological ...

  15. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... biting your nails Nail biting typically begins in childhood and can continue through adulthood, and the side ... set of nails, such as your thumb nails, first. When that’s successful, eliminate your pinky nails, pointer ...

  16. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Mohs AUC MyDermPath+ Psoriasis Patient education resources ... Try to gradually stop biting your nails: Some doctors recommend taking a gradual approach to break the habit. Try to stop biting ...

  17. Design and performance of a high-resolution frictional force microscope with quantitative three-dimensional force sensitivity

    International Nuclear Information System (INIS)

    Dienwiebel, M.; Kuyper, E. de; Crama, L.; Frenken, J.W.M.; Heimberg, J.A.; Spaanderman, D.-J.; Glatra van Loon, D.; Zijlstra, T.; Drift, E. van der

    2005-01-01

    In this article, the construction and initial tests of a frictional force microscope are described. The instrument makes use of a microfabricated cantilever that allows one to independently measure the lateral forces in X and Y directions as well as the normal force. We use four fiber-optic interferometers to detect the motion of the sensor in three dimensions. The properties of our cantilevers allow easy and accurate normal and lateral force calibration, making it possible to measure the lateral force on a fully quantitative basis. First experiments on highly oriented pyrolytic graphite demonstrate that the microscope is capable of measuring lateral forces with a resolution down to 15 pN

  18. High-speed adaptive contact-mode atomic force microscopy imaging with near-minimum-force

    International Nuclear Information System (INIS)

    Ren, Juan; Zou, Qingze

    2014-01-01

    In this paper, an adaptive contact-mode imaging approach is proposed to replace the traditional contact-mode imaging by addressing the major concerns in both the speed and the force exerted to the sample. The speed of the traditional contact-mode imaging is largely limited by the need to maintain precision tracking of the sample topography over the entire imaged sample surface, while large image distortion and excessive probe-sample interaction force occur during high-speed imaging. In this work, first, the image distortion caused by the topography tracking error is accounted for in the topography quantification. Second, the quantified sample topography is utilized in a gradient-based optimization method to adjust the cantilever deflection set-point for each scanline closely around the minimal level needed for maintaining stable probe-sample contact, and a data-driven iterative feedforward control that utilizes a prediction of the next-line topography is integrated to the topography feeedback loop to enhance the sample topography tracking. The proposed approach is demonstrated and evaluated through imaging a calibration sample of square pitches at both high speeds (e.g., scan rate of 75 Hz and 130 Hz) and large sizes (e.g., scan size of 30 μm and 80 μm). The experimental results show that compared to the traditional constant-force contact-mode imaging, the imaging speed can be increased by over 30 folds (with the scanning speed at 13 mm/s), and the probe-sample interaction force can be reduced by more than 15% while maintaining the same image quality

  19. High-speed adaptive contact-mode atomic force microscopy imaging with near-minimum-force

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Juan; Zou, Qingze, E-mail: qzzou@rci.rutgers.edu [Department of Mechanical and Aerospace Engineering, Rutgers University, 98 Brett Rd, Piscataway, New Jersey 08854 (United States)

    2014-07-15

    In this paper, an adaptive contact-mode imaging approach is proposed to replace the traditional contact-mode imaging by addressing the major concerns in both the speed and the force exerted to the sample. The speed of the traditional contact-mode imaging is largely limited by the need to maintain precision tracking of the sample topography over the entire imaged sample surface, while large image distortion and excessive probe-sample interaction force occur during high-speed imaging. In this work, first, the image distortion caused by the topography tracking error is accounted for in the topography quantification. Second, the quantified sample topography is utilized in a gradient-based optimization method to adjust the cantilever deflection set-point for each scanline closely around the minimal level needed for maintaining stable probe-sample contact, and a data-driven iterative feedforward control that utilizes a prediction of the next-line topography is integrated to the topography feeedback loop to enhance the sample topography tracking. The proposed approach is demonstrated and evaluated through imaging a calibration sample of square pitches at both high speeds (e.g., scan rate of 75 Hz and 130 Hz) and large sizes (e.g., scan size of 30 μm and 80 μm). The experimental results show that compared to the traditional constant-force contact-mode imaging, the imaging speed can be increased by over 30 folds (with the scanning speed at 13 mm/s), and the probe-sample interaction force can be reduced by more than 15% while maintaining the same image quality.

  20. An unusual complication of snake bite

    Directory of Open Access Journals (Sweden)

    Mary Grace

    2014-01-01

    Full Text Available Anterior pituitary hypofunction is a well-known complication following snake bite. However, central diabetes insipidus as a complication of snake bite is only rarely reported in the literature. We are reporting a case of central diabetes insipidus, which developed as sequelae to viper bite.

  1. 21 CFR 882.5070 - Bite block.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bite block. 882.5070 Section 882.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5070 Bite block. (a) Identification. A bite block...

  2. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... of hangnails, or other triggers, such as boredom, stress, or anxiety. By figuring out what causes you to bite your nails, you can figure out how to avoid these situations and develop a plan to stop. Just knowing when you’re inclined to bite may help solve the problem. Try to gradually stop biting ...

  3. Snake bite envenomation in Riyadh province of Saudi Arabia over the period (2005–2010)

    Science.gov (United States)

    Al-Sadoon, Mohammed K.

    2014-01-01

    The present investigation is a retrospective review of snake bites in Riyadh province over the period (2005–2010). A total of 1019 cases of bites admitted to the Ministry of Health medical centers in Riyadh province were analyzed on the basis of age, sex, time of bite and its site on the body, outcome of treatment, antiserum dose and type of snake. Bites occurred throughout the six years with the highest frequency in 2005 and least in 2006 where most of the bite cases were mild and all evolved to cure except four patients who died following the administration of antivenom during 24 h after snake bite. Most of the patients were males (81.7%) and the most attacked age was within the range of 11–30 years (51.5%). All the bites were mainly in the exposed limbs and the most frequently bitten anatomical regions were the lower limbs (427 cases, 41.9%), principally the feet. The study incriminates Cerastes cerastes gasperettii in most of the bites indicating it as the snake of medical importance in Riyadh province. Also, the study indicates low degree of threat in spite of high rate of snake bites as a result of the availability of the medical facilities and the antivenin use in medical centers in Riyadh province. PMID:25737653

  4. Motor Unit Interpulse Intervals During High Force Contractions.

    Science.gov (United States)

    Stock, Matt S; Thompson, Brennan J

    2016-01-01

    We examined the means, medians, and variability for motor-unit interpulse intervals (IPIs) during voluntary, high force contractions. Eight men (mean age = 22 years) attempted to perform isometric contractions at 90% of their maximal voluntary contraction force while bipolar surface electromyographic (EMG) signals were detected from the vastus lateralis and vastus medialis muscles. Surface EMG signal decomposition was used to determine the recruitment thresholds and IPIs of motor units that demonstrated accuracy levels ≥ 96.0%. Motor units with high recruitment thresholds demonstrated longer mean IPIs, but the coefficients of variation were similar across all recruitment thresholds. Polynomial regression analyses indicated that for both muscles, the relationship between the means and standard deviations of the IPIs was linear. The majority of IPI histograms were positively skewed. Although low-threshold motor units were associated with shorter IPIs, the variability among motor units with differing recruitment thresholds was comparable.

  5. Mosquito Bite Prevention For Travelers

    Science.gov (United States)

    ... bites. Here’s how: Keep mosquitoes out of your hotel room or lodging Š Choose a hotel or lodging with air conditioning or screens on ... percentages of active ingredient provide longer protection Some brand name examples* (Insect repellents may be sold under ...

  6. Effect of ebastine on mosquito bites.

    Science.gov (United States)

    Reunala, T; Brummer-Korvenkontio, H; Petman, L; Palosuo, T; Sarna, S

    1997-07-01

    Mosquito bites usually cause wealing and delayed bite papules. Cetirizine decreases wealing, bite papules and pruritus but the effect of other antihistamines on mosquito bites is unknown. We studied the effect of ebastine in 30 mosquito bite-sensitive adult subjects. Ebastine 10 mg or 20 mg and placebo were given for 4 days in a cross-over fashion. Aedes aegypti bites were given on forearms. The size of the bite lesions and pruritus (visual analogue score) were measured at 15 min, 2, 6, and 24 h after the bites. Twenty-five subjects were evaluable in the study. At 15 min ebastine decreased significantly the size of the bite lesion (p = 0.0017) and pruritus (ptime points were compiled the size of the bite lesion and pruritus score decreased significantly. Sedation occurred during ebastine treatment in 6 (21%) and during placebo treatment in 2 (7%) subjects. The present results show that prophylactically given ebastine is effective against immediate mosquito bite symptoms.

  7. Clinical Presentation And Outcome Of Snake-Bite Patients At Zamko ...

    African Journals Online (AJOL)

    Objective: To assess the pattern of clinical presentation and management outcome of snake bite victims treated in a comprehensive health centre in a rural setting in North-Central zone of Nigeria where snake bite morbidity and mortality are known to be unacceptably high. Methods: All records of admission in the ...

  8. High-speed atomic force microscopy coming of age

    International Nuclear Information System (INIS)

    Ando, Toshio

    2012-01-01

    High-speed atomic force microscopy (HS-AFM) is now materialized. It allows direct visualization of dynamic structural changes and dynamic processes of functioning biological molecules in physiological solutions, at high spatiotemporal resolution. Dynamic molecular events unselectively appear in detail in an AFM movie, facilitating our understanding of how biological molecules operate to function. This review describes a historical overview of technical development towards HS-AFM, summarizes elementary devices and techniques used in the current HS-AFM, and then highlights recent imaging studies. Finally, future challenges of HS-AFM studies are briefly discussed. (topical review)

  9. High-speed atomic force microscopy coming of age

    Science.gov (United States)

    Ando, Toshio

    2012-02-01

    High-speed atomic force microscopy (HS-AFM) is now materialized. It allows direct visualization of dynamic structural changes and dynamic processes of functioning biological molecules in physiological solutions, at high spatiotemporal resolution. Dynamic molecular events unselectively appear in detail in an AFM movie, facilitating our understanding of how biological molecules operate to function. This review describes a historical overview of technical development towards HS-AFM, summarizes elementary devices and techniques used in the current HS-AFM, and then highlights recent imaging studies. Finally, future challenges of HS-AFM studies are briefly discussed.

  10. Theory of high-force DNA stretching and overstretching.

    Science.gov (United States)

    Storm, C; Nelson, P C

    2003-05-01

    Single-molecule experiments on single- and double-stranded DNA have sparked a renewed interest in the force versus extension of polymers. The extensible freely jointed chain (FJC) model is frequently invoked to explain the observed behavior of single-stranded DNA, but this model does not satisfactorily describe recent high-force stretching data. We instead propose a model (the discrete persistent chain) that borrows features from both the FJC and the wormlike chain, and show that it resembles the data more closely. We find that most of the high-force behavior previously attributed to stretch elasticity is really a feature of the corrected entropic elasticity; the true stretch compliance of single-stranded DNA is several times smaller than that found by previous authors. Next we elaborate our model to allow coexistence of two conformational states of DNA, each with its own stretch and bend elastic constants. Our model is computationally simple and gives an excellent fit through the entire overstretching transition of nicked, double-stranded DNA. The fit gives the first value for the bend stiffness of the overstretched state. In particular, we find the effective bend stiffness for DNA in this state to be about 12 nm k(B)T, a value quite different from either the B-form or single-stranded DNA.

  11. Biting rates and developmental substrates for biting midges (Diptera: Ceratopogonidae) in Iquitos, Peru.

    Science.gov (United States)

    Mercer, David R; Spinelli, Gustavo R; Watts, Douglas M; Tesh, Robert B

    2003-11-01

    Biting midges (Diptera: Ceratopogonidae) were collected at 16 periurban and rural sites around Iquitos, Peru, between 17 October 1996 and 26 May 1997. Culicoides paraensis (Goeldi), the principal vector of Oropouche virus, was the most commonly collected species (9,086 flies) with Culicoides insinuatus Wirth & Blanton second (7,229 flies). Although both species were collected at all sampling sites (linear (distance surveyed approximately 25 km), C. paraensis dominated at northern collection sites (> 90%), whereas C. insinuatus prevailed at southern collection sites (> 60%). C. paraensis were collected from human sentinels at a constant rate throughout daylight hours, at similar rates during wet and dry months, and regardless of rainfall. Larval developmental substrates for C. paraensis included decaying platano (Musa x paradisiaca L. [Musaceae]) stems, stumps, flowers, fruits, and debris beneath platano trees as well as from soil beneath a fruiting mamay (Syzygium malaccense Merr. & Perry [Myrtaceae] ) tree and organic-rich mud along a lake shoreline. C. insinuatus adults likewise emerged from decaying platano and organic-rich mud along a lake shoreline, but also from debris accumulated in the axils of aguaje (Mauritia flexuosa L. [Palmae]) fronds and decaying citrus fruit. Despite high numbers of biting adults near putative substrates, adults of neither species emerged from other decomposing plant material, soil, phytotelmata, or artificial containers. Because both species of biting midges emerged in high numbers from all parts of platano (ubiquitous in Iquitos), it will be challenging to control them through sanitation.

  12. Sexual Dimorphism in Bite Performance Drives Morphological Variation in Chameleons

    Science.gov (United States)

    da Silva, Jessica M.; Herrel, Anthony; Measey, G. John; Tolley, Krystal A.

    2014-01-01

    Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal’s foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal’s performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and

  13. Sexual dimorphism in bite performance drives morphological variation in chameleons.

    Directory of Open Access Journals (Sweden)

    Jessica M da Silva

    Full Text Available Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive

  14. Sexual dimorphism in bite performance drives morphological variation in chameleons.

    Science.gov (United States)

    da Silva, Jessica M; Herrel, Anthony; Measey, G John; Tolley, Krystal A

    2014-01-01

    Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and

  15. High resolution, large deformation 3D traction force microscopy.

    Directory of Open Access Journals (Sweden)

    Jennet Toyjanova

    Full Text Available Traction Force Microscopy (TFM is a powerful approach for quantifying cell-material interactions that over the last two decades has contributed significantly to our understanding of cellular mechanosensing and mechanotransduction. In addition, recent advances in three-dimensional (3D imaging and traction force analysis (3D TFM have highlighted the significance of the third dimension in influencing various cellular processes. Yet irrespective of dimensionality, almost all TFM approaches have relied on a linear elastic theory framework to calculate cell surface tractions. Here we present a new high resolution 3D TFM algorithm which utilizes a large deformation formulation to quantify cellular displacement fields with unprecedented resolution. The results feature some of the first experimental evidence that cells are indeed capable of exerting large material deformations, which require the formulation of a new theoretical TFM framework to accurately calculate the traction forces. Based on our previous 3D TFM technique, we reformulate our approach to accurately account for large material deformation and quantitatively contrast and compare both linear and large deformation frameworks as a function of the applied cell deformation. Particular attention is paid in estimating the accuracy penalty associated with utilizing a traditional linear elastic approach in the presence of large deformation gradients.

  16. Animal Bites in Borujerd: An Overview of Animal Bites in Iran

    Directory of Open Access Journals (Sweden)

    Sabouri Ghannad

    2014-04-01

    Full Text Available Background Rabies has been reported as the most important endemic zoonotic disease in Iran and still remains as a major public health problem. Objectives The main objective of the current research was to study the epidemiology of animal bites in Borujerd County in Iran and to compare its prevalence to other parts of Iran from April 2006 to September 2011. Patients and Methods The data were recorded in questionnaires and analyzed by SPSS version 16. Chi-square test was performed to evaluate the relationship among variables and P value was set as 0.05. Results Dog bites were the most common (69.8%, followed by cat (17.2%, fox and wolf (1.4%, sheep and cow (2.8%, monkey and donkey (5%, mouse and squirrel (2.2% and other animals (1.6%. Leg was the most common bite site forming 46.6% of cases, followed by hands (41.8%, buttocks (4.6%, head (4% and body (2.9%. Most of the subjects belonged to the age group < 10 (175.2 per 100000 populations. The injury location was associated significantly with sex and the residential status. Conclusions This study strongly highlights a high priority goal for health authorities to develop educational programs, recommended for the general population to inform them about the benefits of continuing the medication. Vaccination of domestic dogs and also eradication of stray ones, in addition to educational programs should be prioritized by health authorities.

  17. Mass awareness regarding snake bite induced early morning neuroparalysis can prevent many deaths in North India.

    Science.gov (United States)

    Sharma, Rupinder; Dogra, Varundeep; Sharma, Gurudutt; Chauhan, Vivek

    2016-01-01

    In North India snake bite deaths are predominantly seen with neurotoxic envenomations (NEs) whereas in South India the hemotoxic envenomation (HE) is more common. Krait is responsible for most deaths in North India. It bites people sleeping on the floors, mostly at night. We describe the profile of venomous snake bites over 1 year in 2013. The study was conducted in a rural tertiary care hospital in North India. Demographics, circumstances of bite, envenomation, first aid, delay, consultation, treatment, anti-venom, and outcomes were recorded for all victims of snake bite. We included all consecutive adult (>18 years) venomous snake bite victims admitted from January to December 2013. A total of 91 patients with venomous snake bites were included in the study. Pure NEs were 41 (45.1%), pure HE in 31 (34.1%), 7 (7.7%) had mixed NE + HE, and 12 (13.2%) had only local swelling. Forty patients (44%) were bitten during sleep presenting as NE (92.5%), NE + HE (5%), and HE (2.5%). Findings in the 51 patients (56%) bitten during activity were HE (58.8%), local swelling (23.5%), NE + HE (9.8%), and NE (7.8%) ( P NE patients out of which 23 (96%) went to alternate practitioners or religious healers. Almost all (97.5%) bites during sleep resulted in NE in our study. About 96% of NE sought first aid from alternate practitioners or religious healers in hope of some magical treatment. Thus, a deadly combination of krait bite during sleep and wrong health seeking behavior is responsible for high mortality krait bites in this region. Mass public awareness regarding krait bites can prevent mortality in many such cases.

  18. Nuclear forces and high-performance computing: The perfect match

    International Nuclear Information System (INIS)

    Luu, T; Walker-Loud, A

    2009-01-01

    High-performance computing is now enabling the calculation of certain hadronic interaction parameters directly from Quantum Chromodynamics, the quantum field theory that governs the behavior of quarks and gluons and is ultimately responsible for the nuclear strong force. In this paper we briefly describe the state of the field and show how other aspects of hadronic interactions will be ascertained in the near future. We give estimates of computational requirements needed to obtain these goals, and outline a procedure for incorporating these results into the broader nuclear physics community.

  19. Anger biting. The hidden impulse.

    Science.gov (United States)

    Walter, R D

    1985-09-01

    Based upon the paralogical reasoning of the anger-impulsive biter, this paper addresses the overload of emotional catharsis which can block a full memory of the biting event and suspend the logical infrastructure of rational behavior. In an effort to overcome these types of investigative difficulties, the paper suggests an approach to resolve dilemma through decompressing the emotional content into path ways of logical understanding. By offering a network of rationale hooks, the perpetrator becomes better equipped to acknowledge the deed.

  20. Soft Pneumatic Actuator Fascicles for High Force and Reliability.

    Science.gov (United States)

    Robertson, Matthew A; Sadeghi, Hamed; Florez, Juan Manuel; Paik, Jamie

    2017-03-01

    Soft pneumatic actuators (SPAs) are found in mobile robots, assistive wearable devices, and rehabilitative technologies. While soft actuators have been one of the most crucial elements of technology leading the development of the soft robotics field, they fall short of force output and bandwidth requirements for many tasks. In addition, other general problems remain open, including robustness, controllability, and repeatability. The SPA-pack architecture presented here aims to satisfy these standards of reliability crucial to the field of soft robotics, while also improving the basic performance capabilities of SPAs by borrowing advantages leveraged ubiquitously in biology; namely, the structured parallel arrangement of lower power actuators to form the basis of a larger and more powerful actuator module. An SPA-pack module consisting of a number of smaller SPAs will be studied using an analytical model and physical prototype. Experimental measurements show an SPA pack to generate over 112 N linear force, while the model indicates the benefit of parallel actuator grouping over a geometrically equivalent single SPA scale as an increasing function of the number of individual actuators in the group. For a module of four actuators, a 23% increase in force production over a volumetrically equivalent single SPA is predicted and validated, while further gains appear possible up to 50%. These findings affirm the advantage of utilizing a fascicle structure for high-performance soft robotic applications over existing monolithic SPA designs. An example of high-performance soft robotic platform will be presented to demonstrate the capability of SPA-pack modules in a complete and functional system.

  1. Soft Pneumatic Actuator Fascicles for High Force and Reliability

    Science.gov (United States)

    Robertson, Matthew A.; Sadeghi, Hamed; Florez, Juan Manuel

    2017-01-01

    Abstract Soft pneumatic actuators (SPAs) are found in mobile robots, assistive wearable devices, and rehabilitative technologies. While soft actuators have been one of the most crucial elements of technology leading the development of the soft robotics field, they fall short of force output and bandwidth requirements for many tasks. In addition, other general problems remain open, including robustness, controllability, and repeatability. The SPA-pack architecture presented here aims to satisfy these standards of reliability crucial to the field of soft robotics, while also improving the basic performance capabilities of SPAs by borrowing advantages leveraged ubiquitously in biology; namely, the structured parallel arrangement of lower power actuators to form the basis of a larger and more powerful actuator module. An SPA-pack module consisting of a number of smaller SPAs will be studied using an analytical model and physical prototype. Experimental measurements show an SPA pack to generate over 112 N linear force, while the model indicates the benefit of parallel actuator grouping over a geometrically equivalent single SPA scale as an increasing function of the number of individual actuators in the group. For a module of four actuators, a 23% increase in force production over a volumetrically equivalent single SPA is predicted and validated, while further gains appear possible up to 50%. These findings affirm the advantage of utilizing a fascicle structure for high-performance soft robotic applications over existing monolithic SPA designs. An example of high-performance soft robotic platform will be presented to demonstrate the capability of SPA-pack modules in a complete and functional system. PMID:28289573

  2. Vapor Phase Growth of High-Quality Bi-Te Compounds Using Elemental Bi and Te Sources: A Comparison Between High Vacuum and Atmospheric Pressure

    Science.gov (United States)

    Concepción, O.; Escobosa, A.; de Melo, O.

    2018-03-01

    Bismuth telluride (Bi2Te3), traditionally used in the industry as thermoelectric material, has deserved much attention recently due to its properties as a topological insulator, a kind of material that might have relevant applications in spintronics or quantum computing, among other innovative uses. The preparation of high-quality material has become a very important technological task. Here, we compare the preparation of Bi2Te3 by physical vapor transport from the evaporation of elemental Bi and Te sources, under either low pressure or atmospheric pressure. The layers were characterized by different techniques to evaluate its structural properties. As a result, it is concluded that, as a consequence of the different transport regimes, films grown at atmospheric pressure present better crystal quality.

  3. Monkey Bites among US Military Members, Afghanistan, 2011

    Science.gov (United States)

    Baker, Katheryn A.

    2012-01-01

    Bites from Macaca mulatta monkeys, native to Afghanistan, can cause serious infections. To determine risk for US military members in Afghanistan, we reviewed records for September–December 2011. Among 126 animal bites and exposures, 10 were monkey bites. Command emphasis is vital for preventing monkey bites; provider training and bite reporting promote postexposure treatment. PMID:23017939

  4. Temporomandibular disorders and psychological status in adult patients with a deep bite

    DEFF Research Database (Denmark)

    Sonnesen, Liselotte; Svensson, Peter

    2008-01-01

    Temporomandibular disorders (TMDs) and psychological status were examined in adult patients with a deep bite and compared with an adult age- and gender-matched control group with neutral occlusion. The deep bite group consisted of 20 females (mean age 30.3 years) and 10 males (mean age 33.1 years......). The control group comprised 20 females (mean age 29.4 years) and 10 males (mean age 34.2 years). TMD examination, according to the Research Diagnostic Criteria for TMD (RDC/TMD), cephalometric lateral radiographs, registration of occlusion, and bite force were performed. To test the mean differences between...... group compared with the controls. Somatization scores were significantly higher in the deep bite group compared with the controls (P psychological...

  5. Rat bite fever in a pet lover.

    Science.gov (United States)

    Cunningham, B B; Paller, A S; Katz, B Z

    1998-02-01

    Rat-bite fever is an uncommon bacterial illness resulting from infection with Streptobacillus moniliformis that is often transmitted by the bite of a rat. The cutaneous findings in rat-bite fever are nonspecific but have been described as maculopapular or petechial. We describe a 9-year-old girl with acrally distributed hemorrhagic pustules, fever, and arthralgias. Diagnosis was delayed because of difficulty in identifying the pathologic organism. She was successfully treated with 10 days of ceftriaxone.

  6. Epidemiology of Animal Bites in Azarshahr town: A Cross-sectional Study of Key Determinants

    Directory of Open Access Journals (Sweden)

    Ali Jafari-Khounigh

    2015-08-01

    Full Text Available ​Background and objectives : Animal bites are among the most significant public health problems due to the risk of rabies. Because of high mortality rate and economic damages, rabies is of very importance. This study was conducted to investigate the epidemiology of animal bites in Azarshahr in 2010 and 2011. Material and Methods : In this cross-sectional and descriptive-analytical study, all cases of animal bites in 2010 and 2011 that were recorded in rabies treatment centers of Azarshahr were included in the study using census method according to the existing data recorded in animal bites registry. Data were analyzed using descriptive statistics and Chi-square test using SPSS software. Results : During 2010 and 2011, a total number of 630 animal bites cases occurred that 86.5% of the cases were male. In 51.7% of the cases, animal bites occurred in urban areas. The incidence rate of animal bites was calculated as 291.0 in 100000. The average age and the standard deviation of cases was 31.52±16.73. The main biting animal was domesticated dog (66.3% and most of the bites happened during summer (28.4%. The most injured body organ was hand (47.6%. The association between animal type and injured organ was statistically significant (P Conclusion : Due to the high costs of vaccination and immunoglobulin expenses, prevention strategies seem to be necessary. Since most of the bites were caused by domestic dogs, health education interventions with the aim of more controls on domestic animals could be a cost-effective approach.

  7. Prevent Bite Wounds

    Science.gov (United States)

    ... are also used for children with a weakened immune system. If the animal is unavailable to be observed and the risk of rabies is considered high, your doctor will give your child a specific type of immune globulin and begin a series of immunizations against ...

  8. The influence of bite size and multiple bites on oral texture sensations

    NARCIS (Netherlands)

    Wijk, de R.A.; Engelen, L.; Prinz, J.F.; Weenen, H.

    2003-01-01

    The influence of bite size on sensory mouth- and afterfeel sensations was explored in two studies in which single bites of vanilla custard desserts were varied from 2 to 11 ml (study 1) and in which series of five bites of two different custard desserts were presented consecutively (study 2). In

  9. The influence of bite size and multiple bites on oral texture sensations

    NARCIS (Netherlands)

    Wijk, R.A. de; Engelen, L.; Prinz, J.F.; Weenen, H.

    2003-01-01

    The influence of bite size on sensory mouthfeel and afterfeel sensations was explored in two studies in which single bites of vanilla custard desserts were varied from 2 to 11 mL (study 1) and in which series of five bites of two different custard desserts were presented consecutively (study 2). In

  10. Fluids with highly directional attractive forces. IV. Equilibrium polymerization

    International Nuclear Information System (INIS)

    Wertheim, M.S.

    1986-01-01

    The author investigates approximation methods for systems of molecules interacting by core repulsion and highly directional attraction due to several attraction sites. The force model chosen imitates a chemical bond by providing for bond saturation when binding occurs. The dense fluid is an equilibrium mixture of s-mers with mutual repulsion. The author uses a previously derived reformulation of statistical thermodynamics in which the particle species are monomeric units with a specified set of attraction sites bonded. Thermodynamic perturbation theory (TPT) and integral equations of two types are derived. The use of TPT is illustrated by explicit calculation for a molecular model with two attraction sites capable of forming chain and ring polymers. Successes and defects of TPT are discussed. The integral equations for pair correlations between particles of specified bonding include calculation of self-consistent densities of species. Methods of calculating thermodynamic properties from the solutions of integral equations are given

  11. Consumer perception of salt-reduced breads: Comparison of single and two-bites evaluation.

    Science.gov (United States)

    Antúnez, Lucía; Giménez, Ana; Alcaire, Florencia; Vidal, Leticia; Ares, Gastón

    2017-10-01

    Salt-reduction in processed products has been proposed as a high-impact intervention for reducing the sodium intake at population level. A major limitation for this approach is its potential negative impact on the sensory characteristics of products. The current practice in sensory and consumer science involves single sip/bite evaluations, which may not properly reflect the sensory experience that occurs during product consumption. In this context, the aim of the present work was to compare single and two bite evaluations of consumer sensory and hedonic perception of salt-reduced breads. Five studies with a total of 499 consumers were carried out, in which overall-liking scores of five salt-reduced bread samples were collected after the first and the second bite evaluation. In one of the studies consumers also answered a CATA (check-all-that-apply) question after the first and the second bite. Neither bite nor the interaction between samples and bite had a significant effect on hedonic scores. However, when hedonic scores were analysed separately for each bite, the overall liking scores from the second bite evaluation better reflected differences among samples according to their salt content in two of the five studies. The sensory characterization of the samples did not largely vary between the first and the second bite. Results suggest that consumers' perception of salt reduced bread samples did not largely vary between a single and a two bites evaluation. Further research is warranted in this regard, in particular considering more complex products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Pigs suffering from injurious behaviours like flank biting and tail biting are more interested to manipulate a novel rope than uninjured control animals

    NARCIS (Netherlands)

    Bracke, M.B.M.; Ettema, K.

    2014-01-01

    Injurious behaviours in pigs may involve persistent or forceful biting in specific body parts and may result in wounds of the pigs’ tails, ears, flanks and legs. Such behaviours, which may lead to progressive tissue damage, are difficult to counteract. On a commercial farm 22 groups of pigs with

  13. Talking to Patients about Preventing Tick Bites

    Centers for Disease Control (CDC) Podcasts

    2012-02-14

    This podcast will help health care providers identify patients who are at increased risk of getting tick bites and provide these patients with tick bite prevention and removal tips.  Created: 2/14/2012 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/14/2012.

  14. Functional Analysis and Treatment of Nail Biting

    Science.gov (United States)

    Dufrene, Brad A.; Watson, T. Steuart; Kazmerski, Jennifer S.

    2008-01-01

    This study applied functional analysis methodology to nail biting exhibited by a 24-year-old female graduate student. Results from the brief functional analysis indicated variability in nail biting across assessment conditions. Functional analysis data were then used to guide treatment development and implementation. Treatment included a…

  15. Open bite in prematurely born children.

    Science.gov (United States)

    Harila, V; Heikkinen, T; Grön, M; Alvesalo, L

    2007-01-01

    The aims of this study were to: examine the expression of open bite in prematurely born children and discuss the etiological factors that may lead to bite it. The subjects were 328 prematurely born (cross-sectional study of the Collaborative Perinatal Project in the 1960s and 1970s. Dental documents, including casts and photographs, were taken once at the age of 6-12 years in the mixed dentition. The occlusion was recorded by examining and measuring the hard stone casts. Vertical open bite was recorded only for full erupted teeth. The statistical method used was chi-square analysis. Significant differences in the incidence of anterior open bite (from left to right canine) was found between the preterm and control groups and between gender and ethnic groups. The prevalence of anterior open bite was nearly 9% in the preterm group and almost 7% in the control group. African Americans (9%) had a significantly greater incidence of open bite than Caucasians (3%; Pbite than boys (8% vs 6%; Pbite was increased--especially in preterm African American boys compared to controls (11% vs 8%). The results show differences in the development of anterior open bite between ethnic and gender groups. Premature birth may also influence dental occlusal development. Of importance are the patient's: general health condition; respiratory infections; inadequate nasal- and mouth-breathing; oral habits; and other medical problems. Preterm children may be relatively more predisposed to etiological factors for the development of anterior open bite.

  16. Iguana bites reported to Texas poison centers.

    Science.gov (United States)

    Forrester, Mathias B

    2010-09-01

    Although thousands of iguanas are kept as pets in the United States, information on their bites is limited. The intent of this investigation was to describe the pattern of iguana bites reported to Texas poison centers. Iguana bites reported during 1998-2008 were identified. The distribution of cases by various factors was determined. Of 59 total bites, 71% were managed on-site, 17% of the patients were at or en route to a health care facility when the poison center was contacted, and 10% were referred to a health care facility. The medical outcome was no effect in 9% of the cases, minor effect in 24%, moderate effect in 2%, not followed but minimal effects possible in 64%, and unable to follow but potentially toxic in 2%. Most iguana bites reported to Texas poison centers did not result in serious effects and were managed on-site. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. An Epidemiological Study of Animal Bites and Envenomings in a Rural District of Tamilnadu, India

    Directory of Open Access Journals (Sweden)

    Venkatesan M

    2014-12-01

    Full Text Available Aim: To find out the period prevalence of animal bites and envenomings, its epidemiological risk factors and treatment seeking behaviour. Materials and methods: The present cross sectional study was conducted in the 34 villages of the field practising areas of the Rural Health Training Centre, Thiruvenainallur. Considering the prevalence of bites as 7.4%, and taking 5 members in each household with a non response of 10% the number households studied were 4150 covering a population of 18865 which was calculated using an Open EPI version (2.3 software package. Sampling frame of households was prepared and systemic random sampling method was used to select households from each village. Trained medical interns and social workers collected information on bites in the preceding one year. Data was entered and analyzed in Epi_info (3.4.3 software. Results: In this study, information of 12947 adults was included and the overall period prevalence of bites was 81.8/1000 population. The most common bite is dog bite (22.3 followed by scorpion (22.1 and centipede (17.8 per 1000 population. The dog bites are significantly higher among males, people below the poverty line, farmers and laborers. There is significantly increased risk of snake bites among people working in agriculture fields. Only 35% of the dog bite victims washed their wound with soap and water and 28% applied irritants such as ash, ink, calotropis milk etc. over the wounds. Anti-rabies vaccination was given in 60% of the dog bite victims and life saving measure of Rabies Immunoglobulins (RIGS was given in only in 6.2%. Almost half of the bitten victims of scorpion and centipede follow traditional methods of treatment. Conclusions: Considering the high prevalence of different bites and treatment seeking behavior indicates there is a lack of awareness regarding all forms of bites in the rural community. The existing program of rabies control has to be strengthened and community awareness about

  18. Afibrinogenemia following snake bite (Crotalus durissus terrificus

    Directory of Open Access Journals (Sweden)

    C. F. S. Amaral

    1988-08-01

    Full Text Available This paper reports two cases of afibrinogenemia with normal platelet count following Crotalus durissus terrificus, snake bite Both patients presented high output acute renal failure and case two also had increased blood levels of CPK and LDH compatible with the diagnosis of rhabdomyolysis. Case one was given an unknown amount of antivenom and was treated with epsilonaminocaproic acid and a fresh whole blood transfusion and showed recovery of the coagulation disturbance 40 hours following these measures. Case two was given an adequate amount of crotalide antivenom and the coagulation tests performed 12 hours later showed a normal partial thromboplastin time and fibrinogen 86 mg/100ml. Case one presented no haemorrhagic disturbances. Case two presented persistent bleeding following venopuncture and after removal of impetigo crust in the legs. Acute renal failure was treated conservatively and both patients were discharged from the hospital with recovery of the renal function.

  19. Management of vascular trauma from dog bites.

    Science.gov (United States)

    Akingba, A George; Robinson, Eric A; Jester, Andrea L; Rapp, Brian M; Tsai, Anthony; Motaganahalli, Raghu L; Dalsing, Michael C; Murphy, Michael P

    2013-11-01

    Vascular trauma from large-dog bites present with a combination of crush and lacerating injuries to the vessel, as well as significant adjacent soft tissue injury and a high potential for wound complications. This retrospective case series evaluates our 15 years of experience in managing this uncommonly seen injury into suggested treatment recommendations. From our database, 371 adult patients presented with dog bites between July 1997 and June 2012. Twenty (5.4%) of those patients had vascular injuries requiring surgical intervention. Patient demographics, anatomic location of injury, clinical presentation, imaging modality, method of repair, and complication rates were reviewed to assess efficacy in preserving limb function. Pediatric patients were managed at the regional children's hospital and, therefore, not included in this study. Among the 20 surgically treated vascular injuries, there were 13 arterial-only injuries, two venous-only injuries, and five combination arterial and venous injuries. Seventeen patients (85%) had upper extremity injuries; three patients had lower extremity injuries (15%). The axillobrachial artery was the most commonly injured single vessel (n = 9/20; 45%), followed by the radial artery (n = 4/20; 20%). Surgical repair of vascular injuries consisted of resection and primary anastomosis (four), interposition bypass of artery with autogenous vein (13), and ligation (two), with (one) being a combination of bypass and ligation. All patients had debridement of devitalized tissue combined with pulse lavage irrigation and perioperative antibiotics. Associated injuries requiring repair included muscle and skin (n = 10/20; 50%), bone (n = 1/20; 5%), nerve (n = 1/20; 5%), and combinations of the three (n = 5/20; 25%). Postoperative antibiotic therapy was administered for 14.7 ± 8.2 days in all 20 patients. Four patients (20%) developed postoperative wound infections, although this did not compromise their vascular repair. Of the patients

  20. Shuffle motor: a high force, high precision linear electrostatic stepper motor

    NARCIS (Netherlands)

    Tas, Niels Roelof; Wissink, Jeroen; Sander, A.F.M.; Sander, Louis; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt

    1997-01-01

    The shuffle motor is a electrostatic stepper motor that employs a mechanical transformation to obtain high forces and small steps. A model has been made to calculate the driving voltage, step size and maximum load to pull as well as the optimal geometry. Tests results are an effective step size of

  1. Shortcomings in snake bite management in rural Cameroon: a case report.

    Science.gov (United States)

    Tianyi, Frank-Leonel; Dimala, Christian Akem; Feteh, Vitalis Fambombi

    2017-06-08

    Snake bites are an important public health problem in developing countries with most bites occurring in rural areas. Severe envenomation often occurs in children and following bites to the face. Prompt administration of potent anti-venom remains the mainstay of management. However in Cameroon, the use of anti-venoms is limited by non-availability, high cost (where available) and poor mastery of treatment guidelines. We present a 10-year-old muslim Cameroonian child from an enclaved rural area, brought to the hospital 12 h after a snake bite to the face, with signs of severe envenomation. Despite the suboptimal anti-venom dose administered to this patient due to a stock out of this medication, supportive therapy was beneficial in ensuring a positive outcome and satisfactory recovery. This highlights snake bites as a public health problem due to the lack of snake anti-venoms in peripheral health facilities, rendering them unable to appropriately manage these cases. National health policies should encourage constant peripheral availability of anti-venoms and the institution of an intervention package for snake bite management, comprising: treatment protocol, staff training, monitoring of compliance and community education to help reduce the mortality and morbidity from snake bites.

  2. High cable forces deteriorate pinch force control in voluntary-closing body-powered prostheses

    NARCIS (Netherlands)

    Hichert, M.; Abbink, D.A.; Kyberd, P.J.; Plettenburg, D.H.

    2017-01-01

    Background It is generally asserted that reliable and intuitive control of upper-limb prostheses requires adequate feedback of prosthetic finger positions and pinch forces applied to objects. Bodypowered prostheses (BPPs) provide the user with direct proprioceptive feedback. Currently available

  3. High spatial resolution Kelvin probe force microscopy with coaxial probes

    International Nuclear Information System (INIS)

    Brown, Keith A; Westervelt, Robert M; Satzinger, Kevin J

    2012-01-01

    Kelvin probe force microscopy (KPFM) is a widely used technique to measure the local contact potential difference (CPD) between an AFM probe and the sample surface via the electrostatic force. The spatial resolution of KPFM is intrinsically limited by the long range of the electrostatic interaction, which includes contributions from the macroscopic cantilever and the conical tip. Here, we present coaxial AFM probes in which the cantilever and cone are shielded by a conducting shell, confining the tip–sample electrostatic interaction to a small region near the end of the tip. We have developed a technique to measure the true CPD despite the presence of the shell electrode. We find that the behavior of these probes agrees with an electrostatic model of the force, and we observe a factor of five improvement in spatial resolution relative to unshielded probes. Our discussion centers on KPFM, but the field confinement offered by these probes may improve any variant of electrostatic force microscopy. (paper)

  4. Microbial analysis of bite marks by sequence comparison of streptococcal DNA.

    Directory of Open Access Journals (Sweden)

    Darnell M Kennedy

    Full Text Available Bite mark injuries often feature in violent crimes. Conventional morphometric methods for the forensic analysis of bite marks involve elements of subjective interpretation that threaten the credibility of this field. Human DNA recovered from bite marks has the highest evidentiary value, however recovery can be compromised by salivary components. This study assessed the feasibility of matching bacterial DNA sequences amplified from experimental bite marks to those obtained from the teeth responsible, with the aim of evaluating the capability of three genomic regions of streptococcal DNA to discriminate between participant samples. Bite mark and teeth swabs were collected from 16 participants. Bacterial DNA was extracted to provide the template for PCR primers specific for streptococcal 16S ribosomal RNA (16S rRNA gene, 16S-23S intergenic spacer (ITS and RNA polymerase beta subunit (rpoB. High throughput sequencing (GS FLX 454, followed by stringent quality filtering, generated reads from bite marks for comparison to those generated from teeth samples. For all three regions, the greatest overlaps of identical reads were between bite mark samples and the corresponding teeth samples. The average proportions of reads identical between bite mark and corresponding teeth samples were 0.31, 0.41 and 0.31, and for non-corresponding samples were 0.11, 0.20 and 0.016, for 16S rRNA, ITS and rpoB, respectively. The probabilities of correctly distinguishing matching and non-matching teeth samples were 0.92 for ITS, 0.99 for 16S rRNA and 1.0 for rpoB. These findings strongly support the tenet that bacterial DNA amplified from bite marks and teeth can provide corroborating information in the identification of assailants.

  5. Court presentation of bite mark evidence.

    Science.gov (United States)

    Drinnan, A J; Melton, M J

    1985-12-01

    The uniqueness of an individual's bite mark is generally accepted. The use of bite mark analysis to identify or exclude those suspected of crimes is now a well established activity in forensic dentistry. Although the techniques for evaluating bite mark evidence are extremely sophisticated, it is important that the courtroom presentation of such evidence should be as simple as possible and be directed towards those who must judge it. Dentists likely to be involved in the courtroom presentation of bite mark evidence should: be certain that their local law enforcement personnel are frequently updated on the techniques to be used for producing the optimum evidence needed to evaluate bite marks; become acquainted with the current techniques of evaluating bite mark evidence and understand their difficulties and pitfalls; meet with the lawyers (prosecution or defence) before a courtroom appearance, briefing them on the significance of the particular findings; prepare clear and easily understandable visual aids to present to the court the techniques used in the analysis and the bases for the conclusion reached; and offer conclusions derived from the bite mark investigation.

  6. Relationship of bite mass of cattle to sward structure of four temperate grasses in short-term foraging sessions

    Science.gov (United States)

    Bite mass is a fundamental element of ruminant ingestive behavior and is highly influenced by sward structure. We compared the sward structure of four grasses and related structure to the bite mass of cattle grazing the grasses. Reed canarygrass (RCG; Phalaris arundinacea L), quackgrass (QG; Elytri...

  7. How to Stop Biting Your Nails

    Medline Plus

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  14. [Bites of venomous snakes in Switzerland].

    Science.gov (United States)

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-08

    Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

  15. How to Stop Biting Your Nails

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  3. Human bite as a weapon of assault

    African Journals Online (AJOL)

    resulted more in bites involving females than males. Contusion (47.6%) ... homicides, sexual assault and also in attempted suicide1. It may be found in ... original work is properly cited. ... deployed for determining tests of statistical significance;.

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  9. Theory of high-force DNA stretching and overstretching

    NARCIS (Netherlands)

    Storm, C.; Nelson, P.

    2003-01-01

    Single-molecule experiments on single- and double-stranded DNA have sparked a renewed interest in the force versus extension of polymers. The extensible freely jointed chain (FJC) model is frequently invoked to explain the observed behavior of single-stranded DNA, but this model does not

  10. [Mandible function in taking construction bite for activator].

    Science.gov (United States)

    Irie, M

    1989-06-01

    Functional effects of construction bite for activator (Andresen type) especially on lateral pterygoid muscle, as well as the positional changes of the mandible, hyoid bone and surface EMGs from bilateral anterior temporal (TA) and masseter (MM) muscle, were studied on the electric force scale, MKG, EMG and cephalometric radiographs in 14 subjects with anterior cross bite in mixed dentition. The cephalometric radiographs were taken at the start of each patient's treatment. One was taken with the mandible in the intercuspal position and one was also taken with the activator in the mouth at the overjet improvement. The activator patients were divided into two groups because of differences in the direction of movement of the hyoid bone in the FH plane. In group O (7 patients), the movement of the hyoid bone was at an oblique angle to the FH plane, while in group D (7 patients) the movement ot the hyoid bone with nearly direct below angle to FH plane. The patients were further divided into three types because of differences in the distance between the hyoid bone and mental spine, and combined with the groups OA (3 patients), OB (2 patients), OC (2 patients), DA (5 patients), DB (2 patients) and DC (Naught). The results obtained were as follows: The forces for the construction bite for groups O and D were 2.71 Kg and 2.72 kg, respectively. Type OC required significantly heavier force. (p less than 0.05) In the condylar test, O group was significantly smaller at the start of treatment, but not after overjet improvement. Type OA and OB were also significantly smaller at the start of treatment. (p less than 0.05) Velocity of opening for group D was significantly (p less than 0.05) faster at the start of treatment, but not after that. There was no significant difference in EMGs between the groups, with activator in the mouse D group much increased as it EMGs. The EMGs M/T ratio for both groups was approximately 100% at the start of treatment for overjet improvement. In cases

  11. Open bite treatment using clear aligners.

    Science.gov (United States)

    Guarneri, Maria Paola; Oliverio, Teresa; Silvestre, Ivana; Lombardo, Luca; Siciliani, Giuseppe

    2013-09-01

    A 35-year-old female patient with dentoalveolar open bite of 4 mm, molar Class I malocclusion, centered midlines, moderate crowding, and labial inclination of the lower incisor was treated with clear aligners to reduce protrusion and close the anterior open bite. The result showed that clear aligners were an effective method with which to correct this malocclusion. The treatment was complete after 18 months. The patient was satisfied with her new appearance and function.

  12. Anterior open bite treatment with magnets.

    Science.gov (United States)

    Kiliaridis, S; Egermark, I; Thilander, B

    1990-11-01

    The aim of this study was to examine the effects of repelling magnets on the treatment of anterior open bite and compare them with the effects of acrylic posterior bite-blocks. Twenty patients, aged 9-16 years with skeletal anterior open bite, were randomly divided into two groups. In one group the patients wore posterior repelling magnet splints and in the other they wore acrylic posterior bite-blocks of the same thickness as the magnet splints. The patients were instructed to use their appliance as much as possible (the minimum accepted being 18 hours daily) during a 6-month period. Dental casts, intra-oral photos, and lateral cephalograms were taken before and after treatment, and the patients were also examined regularly to identify the development of any craniomandibular disorders. In the first group, the dental and skeletal vertical relation responded quickly to the magnet treatment. The open bite was generally closed in just under 4 months, especially in patients in early mixed dentition. Spacing in the labial segments decreased in some cases, while slight crowding was induced in others. Transverse problems, i.e. unilateral cross-bite, sometimes followed by scissor-bite on the opposite side, was observed in those patients who were in the early mixed dentition and had used the magnets intensively. The patients who wore acrylic posterior bite-blocks also showed improvement in the dental and skeletal vertical relationships, especially during the first months. This was followed by a 'plateau' period. No transverse problems were found in these patients.

  13. Microbiology of Animal Bite Wound Infections

    Science.gov (United States)

    Abrahamian, Fredrick M.; Goldstein, Ellie J. C.

    2011-01-01

    Summary: The microbiology of animal bite wound infections in humans is often polymicrobial, with a broad mixture of aerobic and anaerobic microorganisms. Bacteria recovered from infected bite wounds are most often reflective of the oral flora of the biting animal, which can also be influenced by the microbiome of their ingested prey and other foods. Bacteria may also originate from the victim's own skin or the physical environment at the time of injury. Our review has focused on bite wound infections in humans from dogs, cats, and a variety of other animals such as monkeys, bears, pigs, ferrets, horses, sheep, Tasmanian devils, snakes, Komodo dragons, monitor lizards, iguanas, alligators/crocodiles, rats, guinea pigs, hamsters, prairie dogs, swans, and sharks. The medical literature in this area has been made up mostly of small case series or case reports. Very few studies have been systematic and are often limited to dog or cat bite injuries. Limitations of studies include a lack of established or inconsistent criteria for an infected wound and a failure to utilize optimal techniques in pathogen isolation, especially for anaerobic organisms. There is also a lack of an understanding of the pathogenic significance of all cultured organisms. Gathering information and conducting research in a more systematic and methodical fashion through an organized research network, including zoos, veterinary practices, and rural clinics and hospitals, are needed to better define the microbiology of animal bite wound infections in humans. PMID:21482724

  14. Highly-Integrated Hydraulic Smart Actuators and Smart Manifolds for High-Bandwidth Force Control

    Directory of Open Access Journals (Sweden)

    Victor Barasuol

    2018-06-01

    Full Text Available Hydraulic actuation is the most widely used alternative to electric motors for legged robots and manipulators. It is often selected for its high power density, robustness and high-bandwidth control performance that allows the implementation of force/impedance control. Force control is crucial for robots that are in contact with the environment, since it enables the implementation of active impedance and whole body control that can lead to a better performance in known and unknown environments. This paper presents the hydraulic Integrated Smart Actuator (ISA developed by Moog in collaboration with IIT, as well as smart manifolds for rotary hydraulic actuators. The ISA consists of an additive-manufactured body containing a hydraulic cylinder, servo valve, pressure/position/load/temperature sensing, overload protection and electronics for control and communication. The ISA v2 and ISA v5 have been specifically designed to fit into the legs of IIT’s hydraulic quadruped robots HyQ and HyQ-REAL, respectively. The key features of these components tackle 3 of today’s main challenges of hydraulic actuation for legged robots through: (1 built-in controllers running inside integrated electronics for high-performance control, (2 low-leakage servo valves for reduced energy losses, and (3 compactness thanks to metal additive manufacturing. The main contributions of this paper are the derivation of the representative dynamic models of these highly integrated hydraulic servo actuators, a control architecture that allows for high-bandwidth force control and their experimental validation with application-specific trajectories and tests. We believe that this is the first work that presents additive-manufactured, highly integrated hydraulic smart actuators for robotics.

  15. Force and Motion Characteristics of Contamination Particles near the High Voltage End of UHVDC Insulator

    Directory of Open Access Journals (Sweden)

    Lei Lan

    2017-07-01

    Full Text Available It is important to reveal the relations of physical factors to deposition of contaminants on insulator. In this paper, the simulation model of high voltage end of insulator was established to study the force and motion characteristics of particles affected by electric force and airflow drag force near the ultra-high voltage direct current (UHVDC insulator. By finite element method, the electric field was set specially to be similar to the one near practical insulator, the steady fluid field was simulated. The electric force and air drag force were loaded on the uniformly charged particles. The characteristics of the two forces on particles, the relationship between quantity of electric charge on particles and probability of particles contacting the insulator were analyzed. It was found that, near the sheds, airflow drag force on particles is significantly greater than electric force with less electric charge. As the charge multiplies, electric force increases linearly, airflow drag force grows more slowly. There is a trend that the magnitude of electric force and drag force is going to similar. Meanwhile, the probability of particles contacting the insulator is increased too. However, at a certain level of charge which has different value with different airflow velocity, the contact probability has extremum here. After exceeding the value, as the charge increasing, the contact probability decreases gradually.

  16. Synthetic oligorotaxanes exert high forces when folding under mechanical load

    Science.gov (United States)

    Sluysmans, Damien; Hubert, Sandrine; Bruns, Carson J.; Zhu, Zhixue; Stoddart, J. Fraser; Duwez, Anne-Sophie

    2018-01-01

    Folding is a ubiquitous process that nature uses to control the conformations of its molecular machines, allowing them to perform chemical and mechanical tasks. Over the years, chemists have synthesized foldamers that adopt well-defined and stable folded architectures, mimicking the control expressed by natural systems1,2. Mechanically interlocked molecules, such as rotaxanes and catenanes, are prototypical molecular machines that enable the controlled movement and positioning of their component parts3-5. Recently, combining the exquisite complexity of these two classes of molecules, donor-acceptor oligorotaxane foldamers have been synthesized, in which interactions between the mechanically interlocked component parts dictate the single-molecule assembly into a folded secondary structure6-8. Here we report on the mechanochemical properties of these molecules. We use atomic force microscopy-based single-molecule force spectroscopy to mechanically unfold oligorotaxanes, made of oligomeric dumbbells incorporating 1,5-dioxynaphthalene units encircled by cyclobis(paraquat-p-phenylene) rings. Real-time capture of fluctuations between unfolded and folded states reveals that the molecules exert forces of up to 50 pN against a mechanical load of up to 150 pN, and displays transition times of less than 10 μs. While the folding is at least as fast as that observed in proteins, it is remarkably more robust, thanks to the mechanically interlocked structure. Our results show that synthetic oligorotaxanes have the potential to exceed the performance of natural folding proteins.

  17. Biting behaviour of African malaria vectors: 1. where do the main vector species bite on the human body?

    Science.gov (United States)

    Braack, Leo; Hunt, Richard; Koekemoer, Lizette L; Gericke, Anton; Munhenga, Givemore; Haddow, Andrew D; Becker, Piet; Okia, Michael; Kimera, Isaac; Coetzee, Maureen

    2015-02-04

    Malaria control in Africa relies heavily on indoor vector management, primarily indoor residual spraying and insecticide treated bed nets. Little is known about outdoor biting behaviour or even the dynamics of indoor biting and infection risk of sleeping household occupants. In this paper we explore the preferred biting sites on the human body and some of the ramifications regarding infection risk and exposure management. We undertook whole-night human landing catches of Anopheles arabiensis in South Africa and Anopheles gambiae s.s. and Anopheles funestus in Uganda, for seated persons wearing short sleeve shirts, short pants, and bare legs, ankles and feet. Catches were kept separate for different body regions and capture sessions. All An. gambiae s.l. and An. funestus group individuals were identified to species level by PCR. Three of the main vectors of malaria in Africa (An. arabiensis, An. gambiae s.s. and An. funestus) all have a preference for feeding close to ground level, which is manifested as a strong propensity (77.3% - 100%) for biting on lower leg, ankles and feet of people seated either indoors or outdoors, but somewhat randomly along the lower edge of the body in contact with the surface when lying down. If the lower extremities of the legs (below mid-calf level) of seated people are protected and therefore exclude access to this body region, vector mosquitoes do not move higher up the body to feed at alternate body sites, instead resulting in a high (58.5% - 68.8%) reduction in biting intensity by these three species. Protecting the lower limbs of people outdoors at night can achieve a major reduction in biting intensity by malaria vector mosquitoes. Persons sleeping at floor level bear a disproportionate risk of being bitten at night because this is the preferred height for feeding by the primary vector species. Therefore it is critical to protect children sleeping at floor level (bednets; repellent-impregnated blankets or sheets, etc

  18. Case Report of a Newborn Injured By Human Bite

    Directory of Open Access Journals (Sweden)

    Emel Ataoğlu

    2015-03-01

    Full Text Available Bite is a type of wound received from the teeth of an animal, including humans. Human bites are third leading cause of all bites after dog and cat bites. Human bites are severe wounds due to the risk of contamination with mix oral flora and rapid tissue destruction. Bite wounds created by humans are seen in variety of circumstances including aggression, rape, murder, and child abuse. Oral cavity contains beta-hemolytic streptococci, anaerobes and other microorganisms. There have been reported cases of septicemia, severe necrotizing fasciitis, HIV infection, and death caused by human bites. Early reporting and treatment of bite wounds decrease the number and severity of wound infection. Here, we present the case of human bite in a nine-day-old girl and discuss the treatment approaches in the light of the relevant literature.

  19. The epidemiology of bite and scratch injuries by vertebrate animals in Switzerland

    International Nuclear Information System (INIS)

    Matter, Hans C.

    1998-01-01

    Pet and wildlife populations are a potential source of various public health problems, and injuries and complications due to animal bites and scratches are the most obvious. As no population based data on the frequency of animal bites were available at a national level in Switzerland, a study was conducted by the Swiss Sentinel Surveillance Network. The objectives of this study were to estimate the incidence of medical consultations due to bite and scratch injuries in humans caused by vertebrate animals, to identify possible risk factors, and to assess bite management habits in primary health care. An annual bite and scratch incidence rate of 325 per 100,000 population was estimated. Consultations peaked during the summer months and geographical differences in the reported incidence were observed. Dogs accounted for more than 60% and cats for about 25% of all cases reported. Animal bites and scratches were frequent in persons under 20 years of age. In most ages, the incidence was higher among women than among men, but not in children under the age of ten years. The incidence of cat bites was especially high in adult women. Bites to the head and neck were most frequent in infants and young children and accounted for approximately one third of the reported cases in this age group. Patients sought medical care principally for primary wound care (52.0%) and for vaccination advice (29.6%). Rabies postexposure prophylaxis was initiated in 1.1% of patients. Wound infection was reported in 10.9% of cases, with cat bites/scratches being more often infected than injuries due to dogs. Hospitalization was reported in 0.3% of patients. Data from the emergency department of two district hospitals showed that head and neck injuries were more frequent in out-patients and a higher proportion of persons presented with wound infections (14.1%). The hospitalization rate for emergency department visits was 4.7%. Animal bites and scratches are common events in Switzerland. They

  20. Length-extension resonator as a force sensor for high-resolution frequency-modulation atomic force microscopy in air.

    Science.gov (United States)

    Beyer, Hannes; Wagner, Tino; Stemmer, Andreas

    2016-01-01

    Frequency-modulation atomic force microscopy has turned into a well-established method to obtain atomic resolution on flat surfaces, but is often limited to ultra-high vacuum conditions and cryogenic temperatures. Measurements under ambient conditions are influenced by variations of the dew point and thin water layers present on practically every surface, complicating stable imaging with high resolution. We demonstrate high-resolution imaging in air using a length-extension resonator operating at small amplitudes. An additional slow feedback compensates for changes in the free resonance frequency, allowing stable imaging over a long period of time with changing environmental conditions.

  1. Human bite wounds: a swiss emergency department experience.

    Science.gov (United States)

    Tabbara, Malek; Hatzigianni, Panagiota; Fux, Christoph; Zimmermann, Heinz; Exadaktylos, Aristomenis K

    2012-04-01

     Human bites (HB) are the third most common bite wound diagnosed in emergency departments, after dog and cat bites. Management of HB can be challenging, given the high risk of infection associated with multiorganism-rich oral flora. Recognition and early aggressive treatment are essential steps in preventing infections and other associated complications. A retrospective, 10-year electronic chart review was performed, which identified 104 HB. Diagnosis, treatment, and outcome were noted for each case. Most of the patients were male, with a male:female ratio of 4:1. A majority of patients (n = 53, 51%) presented with finger and hand injuries. Only 13.8% were bitten on the head or neck, and 25% on the upper limbs. The remainder (35.2%) of patients sustained injuries to other body parts. Twelve operations were necessary and performed by plastic and hand surgeons. More than half of the patients (60.5%) received antibiotic therapy, and 84.6% of the patients had their tetanus prophylaxis administered or received a booster by the time of treatment. Only 40.4% of patients had a post-bite serology test to rule out bloodborne viral infections, none of whom tested positive. The viral status of the biter was known in two cases. The goals of HB management are to minimize infection risk and its complications, and to prevent the transmission of systemic infections, such as hepatitis B/C and HIV. Accurate documentation and a management algorithm should be instituted in emergency departments in order to achieve these goals. .

  2. High-speed atomic force microscope imaging: Adaptive multiloop mode

    Science.gov (United States)

    Ren, Juan; Zou, Qingze; Li, Bo; Lin, Zhiqun

    2014-07-01

    In this paper, an imaging mode (called the adaptive multiloop mode) of atomic force microscope (AFM) is proposed to substantially increase the speed of tapping mode (TM) imaging while preserving the advantages of TM imaging over contact mode (CM) imaging. Due to its superior image quality and less sample disturbances over CM imaging, particularly for soft materials such as polymers, TM imaging is currently the most widely used imaging technique. The speed of TM imaging, however, is substantially (over an order of magnitude) lower than that of CM imaging, becoming the major bottleneck of this technique. Increasing the speed of TM imaging is challenging as a stable probe tapping on the sample surface must be maintained to preserve the image quality, whereas the probe tapping is rather sensitive to the sample topography variation. As a result, the increase of imaging speed can quickly lead to loss of the probe-sample contact and/or annihilation of the probe tapping, resulting in image distortion and/or sample deformation. The proposed adaptive multiloop mode (AMLM) imaging overcomes these limitations of TM imaging through the following three efforts integrated together: First, it is proposed to account for the variation of the TM deflection when quantifying the sample topography; second, an inner-outer feedback control loop to regulate the TM deflection is added on top of the tapping-feedback control loop to improve the sample topography tracking; and, third, an online iterative feedforward controller is augmented to the whole control system to further enhance the topography tracking, where the next-line sample topography is predicted and utilized to reduce the tracking error. The added feedback regulation of the TM deflection ensures the probe-sample interaction force remains near the minimum for maintaining a stable probe-sample interaction. The proposed AMLM imaging is tested and demonstrated by imaging a poly(tert-butyl acrylate) sample in experiments. The

  3. Early orthodontic treatment of skeletal open-bite malocclusion with the open-bite bionator: a cephalometric study.

    Science.gov (United States)

    Defraia, Efisio; Marinelli, Andrea; Baroni, Giulia; Franchi, Lorenzo; Baccetti, Tiziano

    2007-11-01

    This study was designed to evaluate the effectiveness of the open-bite bionator in growing subjects with increased vertical dimensions. The records of 20 subjects with high-angle skeletal relationships (MPA > or =25 degrees) were examined. Cephalometric measurements were compared with those obtained from 23 sets of records of an untreated group matched according to age, sex, vertical skeletal relationships, and time intervals between records. Lateral cephalograms were analyzed before the start of treatment (mean age; 8.3 years) and after therapy and retention, with a mean period of observation of 2.5 years. The treated group had a significantly smaller palatal plane-mandibular plane angle (-1.9 degrees) and a greater overbite (+1.5 mm) associated with a significantly smaller overjet when compared with the control group. Based on the analysis of this sample, early treatment of skeletal open bite with the open-bite bionator appears to produce a modest effect that mainly consists of significant improvement in intermaxillary divergence. No favorable effects on the extrusion of posterior teeth were found.

  4. Are BiTEs the "missing link" in cancer therapy?

    Science.gov (United States)

    Suryadevara, Carter M; Gedeon, Patrick C; Sanchez-Perez, Luis; Verla, Terence; Alvarez-Breckenridge, Christopher; Choi, Bryan D; Fecci, Peter E; Sampson, John H

    2015-06-01

    Conventional treatment for cancer routinely includes surgical resection and some combination of chemotherapy and radiation. These approaches are frequently accompanied by unintended and highly toxic collateral damage to healthy tissues, which are offset by only marginal prognostic improvements in patients with advanced cancers. This unfortunate balance has driven the development of novel therapies that aim to target tumors both safely and efficiently. Over the past decade, mounting evidence has supported the therapeutic utility of T-cell-centered cancer immunotherapy, which, in its various iterations, has been shown capable of eliciting highly precise and robust antitumor responses both in animal models and human trials. The identification of tumor-specific targets has further fueled a growing interest in T-cell therapies given their potential to circumvent the non-specific nature of traditional treatments. Of the several strategies geared toward achieving T-cell recognition of tumor, bispecific antibodies (bsAbs) represent a novel class of biologics that have garnered enthusiasm in recent years due to their versatility, specificity, safety, cost, and ease of production. Bispecific T-cell Engagers (BiTEs) are a subclass of bsAbs that are specific for CD3 on one arm and a tumor antigen on the second. As such, BiTEs function by recruiting and activating polyclonal populations of T-cells at tumor sites, and do so without the need for co-stimulation or conventional MHC recognition. Blinatumomab, a well-characterized BiTE, has emerged as a promising recombinant bscCD19×CD3 construct that has demonstrated remarkable antitumor activity in patients with B-cell malignancies. This clinical success has resulted in the rapid extension of BiTE technology against a greater repertoire of tumor antigens and the recent US Food and Drug Administration's (FDA) accelerated approval of blinatumomab for the treatment of a rare form of acute lymphoblastic leukemia (ALL). In this review

  5. Epidemiological Study of Animal Bite in Students in Hashtrood Town: 2006- 2010

    Directory of Open Access Journals (Sweden)

    Javad Babaie

    2015-08-01

    Full Text Available Background and objectives : Rabies is an acute and fatal infectious disease that is very important due to high economic losses to livestock and the amounts of expenditures that are paid for purchasing serum and vaccine. The main way of disease transmitting is bites by rabid animals. Animal bite is an important threat for human health. The main aim of this research was epidemiological study of animal bite in the students of Hashtrood town. Material and Methods : In this cross-sectional study, animal bitten students’ data were collected trough the records of Hashtrood health centers registry lists between 2006-2009. The census data collecting method was used and the data were analyzed with statistical software SPSS15. Results : The incidence of animal bites in the past 5 years was 9.07 per 1,000 students. From 439 animal bitten students, 80.9% were male and 19.1% were female. According to the results, 88.4% were rural and 11.2% were urban residents. Dogs bite was the cause of 87.92%. In 86.5% of the cases, the bite was superficial and in 8.4% of the cases, bites were deeper. Among them, 16.6% received anti rabies serum, 16.2% received vaccine. This study showed that 4.8% had a previous history of bite. Of total, 78.8% made a visit to health centers in the first 24 hours, 11.4% within 25 to 48 hours, and 3.6% within 49 to 72 hours after bites. There was no human death report from rabies. Results showed that 95.2% were given incomplete vaccination and 4.1% had received five complete vaccines. Conclusion : Regarding the high prevalence of animal bites among students, educating students about the importance of rabies, students’ behavior with dogs and immediate visit to health centers after exposure to dogs should be taken serious. Restraining dogs by training dog owners and legal means should be attempted.

  6. Force Structure. DOD Needs to Integrate Data into Its Force Identification Process and Examine Options to Meet Requirements for High-Demand Support Forces

    National Research Council Canada - National Science Library

    2006-01-01

    ...) will continue to meet its requirements using an all-volunteer force. The Army, in particular, has faced continuing demand for large numbers of forces, especially for forces with support skills...

  7. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... var c = 0; c Tips to prevent and treat bug bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme disease, and malaria. Particularly if you’re ...

  8. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... bites Although most bug bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme ... and tuck your shirt into your pants. You can also pre-treat outer layers of clothing with ...

  9. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care ... bites and stings can be safely treated at home. To treat bug bites and stings at home, ...

  10. High resolution magnetic force microscopy using focused ion beam modified tips

    NARCIS (Netherlands)

    Phillips, G.N.; Siekman, Martin Herman; Abelmann, Leon; Lodder, J.C.

    2002-01-01

    Atomic force microscope tips coated by the thermal evaporation of a magnetic 30 nm thick Co film have been modified by focused ion beam milling with Ga+ ions to produce tips suitable for magnetic force microscopy. Such tips possess a planar magnetic element with high magnetic shape anisotropy, an

  11. Stokes versus Basset: comparison of forces governing motion of small bodies with high acceleration

    Science.gov (United States)

    Krafcik, A.; Babinec, P.; Frollo, I.

    2018-05-01

    In this paper, the importance of the forces governing the motion of a millimetre-sized sphere in a viscous fluid has been examined. As has been shown previously, for spheres moving with a high initial acceleration, the Basset history force should be used, as well as the commonly used Stokes force. This paper introduces the concept of history forces, which are almost unknown to students despite their interesting mathematical structure and physical meaning, and shows the implementation of simple and efficient numerical methods as a MATLAB code to simulate the motion of a falling sphere. An important application of this code could be, for example, the simulation of microfluidic systems, where the external forces are very large and the relevant timescale is in the order of milliseconds to seconds, and therefore the Basset history force cannot be neglected.

  12. High velocity properties of the dynamic frictional force between ductile metals

    International Nuclear Information System (INIS)

    Hammerberg, James Edward; Hollan, Brad L.; Germann, Timothy C.; Ravelo, Ramon J.

    2010-01-01

    The high velocity properties of the tangential frictional force between ductile metal interfaces seen in large-scale NonEquilibrium Molecular Dynamics (NEMD) simulations are characterized by interesting scaling behavior. In many cases a power law decrease in the frictional force with increasing velocity is observed at high velocities. We discuss the velocity dependence of the high velocity branch of the tangential force in terms of structural transformation and ultimate transition, at the highest velocities, to confined fluid behavior characterized by a critical strain rate. The particular case of an Al/Al interface is discussed.

  13. Bacteremia with Bacteroides pyogenes after a cat bite

    DEFF Research Database (Denmark)

    Madsen, Ida Ringsborg; Justesen, Ulrik Stenz

    2011-01-01

    Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite.......Animal bite wounds are often infected with bacteria from the animal's oral flora. We report what we believe to be the first case of bacteremia with Bacteroides pyogenes resulting from an infected cat bite....

  14. Scrotal dog bite: unusual case and review of pediatric literature.

    Science.gov (United States)

    Bertozzi, M; Prestipino, M; Nardi, N; Falcone, F; Appignani, A

    2009-09-01

    Animal bites to human external genitalia are rare. Only a few cases of scrotal dog bite in children have been reported. We present an additional specific case of a scrotal dog bite in a child because the lesion and its repair have not been previously reported in published pediatric studies. A traumatic resection of the right testicular vas deferens was repaired by microsurgical vasoepididymal anastomosis. A review of the published data was also performed to analyze the management of scrotal dog bite lesions.

  15. Cheek-biting disorder: another stereotypic movement disorder?

    Science.gov (United States)

    Sarkhel, Sujit; Praharaj, Samir Kumar; Akhtar, Sayeed

    2011-12-01

    Recurrent cheek biting, a form of self-injurious behavior is a rare entity which presents mostly to dentists and dermatologists. We report a case of recurrent severe cheek biting in an adult male leading to mucosal ulceration. The stereotypic pattern of cheek biting and associated behavior bears striking resemblance to other impulse control disorders. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Vine snake (Thelotornis capensis bite in a dog : clinical communication

    Directory of Open Access Journals (Sweden)

    J. Otto

    2003-06-01

    Full Text Available A vine snake bite in a dog is reported. There was continued minor bleeding from the assumed nose bite site for 4 days. Currently manufactured snakebite antivenom is not effective against vine snake bites and treatment is supportive.

  17. Metabolic changes of masseter muscle in experimental unilateral bite-raised rat determined by 31P-MRS

    International Nuclear Information System (INIS)

    Nishide, Naoto

    1997-01-01

    Occlusal interference is known to alter the functional activity of masticatory muscle, but no alteration of the energy metabolism of masticatory muscle which has gone occlusal interference has been reported. The purpose of this study was to investigate the energy metabolism in rat masseter muscle during masticatory movements following unilateral bite-raising. A bite-raising splint (1 mm) was fixed on the unilateral upper molar of experimental rats, and after 2, 4 and 6 weeks, the rats were anesthetized and masticatory movements were induced by electrical stimulation applied to the masseter muscle (with a biting force of 40 g, a frequency of 5 Hz and a stimulation time of 32 min). 31 P Magnetic Resonance Spectroscopy of the masseter muscle were recorded during a sequence of rest, stimulation and recovery periods, and the resonance signal area ratio of PCr and Pi ((PCr)/(PCr + Pi)) and the muscle pH were determined. After 4 and 6 weeks following the bite-raising, the masseter of the bite-raised side showed a decrease in the (PCr)/(PCr + Pi) ratio compared with a control group during stimulation (p<0.05). Neither the bite-raised side masseter at 2 weeks and the contralateral side at 4 weeks showed any differences compared with the control. The muscle pH during stimulation was similar in both the control and the bite-raised groups of rats. These findings suggest that the occlusal alteration induced by unilateral bite-raising reduces the masseter energy level during mastication. (author)

  18. Metabolic changes of masseter muscle in experimental unilateral bite-raised rat determined by {sup 31}P-MRS

    Energy Technology Data Exchange (ETDEWEB)

    Nishide, Naoto [Kyoto Prefectural Univ. of Medicine (Japan)

    1997-05-01

    Occlusal interference is known to alter the functional activity of masticatory muscle, but no alteration of the energy metabolism of masticatory muscle which has gone occlusal interference has been reported. The purpose of this study was to investigate the energy metabolism in rat masseter muscle during masticatory movements following unilateral bite-raising. A bite-raising splint (1 mm) was fixed on the unilateral upper molar of experimental rats, and after 2, 4 and 6 weeks, the rats were anesthetized and masticatory movements were induced by electrical stimulation applied to the masseter muscle (with a biting force of 40 g, a frequency of 5 Hz and a stimulation time of 32 min). {sup 31}P Magnetic Resonance Spectroscopy of the masseter muscle were recorded during a sequence of rest, stimulation and recovery periods, and the resonance signal area ratio of PCr and Pi ((PCr)/(PCr + Pi)) and the muscle pH were determined. After 4 and 6 weeks following the bite-raising, the masseter of the bite-raised side showed a decrease in the (PCr)/(PCr + Pi) ratio compared with a control group during stimulation (p<0.05). Neither the bite-raised side masseter at 2 weeks and the contralateral side at 4 weeks showed any differences compared with the control. The muscle pH during stimulation was similar in both the control and the bite-raised groups of rats. These findings suggest that the occlusal alteration induced by unilateral bite-raising reduces the masseter energy level during mastication. (author)

  19. Periodontal and gingival incisor findings in patients with anterior open bite in the mixed dentition.

    Science.gov (United States)

    Bechtold, Till Edward; Briegleb, Henning K

    2010-05-01

    The objective of this study was to investigate any association between anterior open bite and periodontal health of the front teeth during mixed dentition. We investigated the periodontal and gingival status of the teeth with dysfunctional and/or subfunctional loading in the open-bite area in 9- to 12-year-old children. We examined 36 subjects with anterior open bite between the ages of 9 and 12 years who had presented for the first time at the Department of Orthodontics, University of Tübingen. A control group of 36 children of the same age with a physiologic incisor relationship--vertical overbite and sagittal overjet were between 1 and 3 mm--were compared. In addition to overjet, the Silness-Löe plaque index, the modified Löe-Silness gingival index, pocket depth and attachment loss were measured and documented at each of the four surfaces (mesial, distal, oral and vestibular) of the upper and lower incisors. The subjects with anterior open bite exhibited significantly more plaque in the malocclusion area than children with a physiologic incisor relationship; the differences were statistically highly significant. The subjects with anterior open bite demonstrated slightly higher degrees of inflammation and a slight increase in periodontal pocket depths than the control group. Periodontal attachment loss was diagnosed in very few areas in both study groups, while attachment loss was slightly more frequent in those with anterior open bite. We observed a higher risk for caries in the malocclusion area in the late mixed dentition phase, as the subjects with anterior open bite presented significantly more plaque accumulation in the incisor area. However, no pathological periodontal anomalies have been detected so far.

  20. prevalence of biting and non-biting flies in relation to species

    African Journals Online (AJOL)

    USER

    The biting effects on resident animals and ... and second largest tourist destination in Nigeria will require concerted efforts to put in proper ... hosts from pool of available susceptible hosts (Okoth ..... communities of the lower Cross River Basin.

  1. Compensator design for improved counterbalancing in high speed atomic force microscopy

    OpenAIRE

    Bozchalooi, I. S.; Youcef-Toumi, K.; Burns, D. J.; Fantner, G. E.

    2011-01-01

    High speed atomic force microscopy can provide the possibility of many new scientific observations and applications ranging from nano-manufacturing to the study of biological processes. However, the limited imaging speed has been an imperative drawback of the atomic force microscopes. One of the main reasons behind this limitation is the excitation of the AFM dynamics at high scan speeds, severely undermining the reliability of the acquired images. In this research, we propose a piezo based, ...

  2. Experimental StudyHigh Altitude Forced Convective Cooling of Electromechanical Actuation Systems

    Science.gov (United States)

    2016-01-01

    34 Massachusetts Institute of Technology , 1989. [3] FedBizOps.Gov, " Integrated Vehicle Energy Technology (INVENT) Development Program for the 6th...AFRL-RQ-WP-TR-2016-0043 EXPERIMENTAL STUDY—HIGH ALTITUDE FORCED CONVECTIVE COOLING OF ELECTROMECHANICAL ACTUATION SYSTEMS Evan M. Racine...TITLE AND SUBTITLE EXPERIMENTAL STUDY—HIGH ALTITUDE FORCED CONVECTIVE COOLING OF ELECTROMECHANICAL ACTUATION SYSTEMS 5a. CONTRACT NUMBER In-house

  3. Force scanning: a rapid, high-resolution approach for spatial mechanical property mapping

    International Nuclear Information System (INIS)

    Darling, E M

    2011-01-01

    Atomic force microscopy (AFM) can be used to co-localize mechanical properties and topographical features through property mapping techniques. The most common approach for testing biological materials at the microscale and nanoscale is force mapping, which involves taking individual force curves at discrete sites across a region of interest. The limitations of force mapping include long testing times and low resolution. While newer AFM methodologies, like modulated scanning and torsional oscillation, circumvent this problem, their adoption for biological materials has been limited. This could be due to their need for specialized software algorithms and/or hardware. The objective of this study is to develop a novel force scanning technique using AFM to rapidly capture high-resolution topographical images of soft biological materials while simultaneously quantifying their mechanical properties. Force scanning is a straightforward methodology applicable to a wide range of materials and testing environments, requiring no special modification to standard AFMs. Essentially, if a contact-mode image can be acquired, then force scanning can be used to produce a spatial modulus map. The current study first validates this technique using agarose gels, comparing results to ones achieved by the standard force mapping approach. Biologically relevant demonstrations are then presented for high-resolution modulus mapping of individual cells, cell-cell interfaces, and articular cartilage tissue.

  4. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... biting "); (function () { var a = "", b = [ "adid=aad-aad-1", "site=ehs.con.aad.aad", "size=160x600", "vpos=t", "hpos=l", "zone=public", "mcat1=de12", ]; for (var c = 0; c "); (function () { var a = "", b = [ "adid=aad-aad- ...

  5. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Mohs AUC MyDermPath+ Psoriasis Patient education resources Practice Management Center Coding and reimbursement Coding MACRA Fee schedule ... Child nail care Manicure safety Nail biting Nail changes a dermatologist should examine Anti-aging skin care ...

  6. Non-biting Muscidae and control methods

    DEFF Research Database (Denmark)

    Thomas, G.; Jespersen, Jørgen B.

    1994-01-01

    Many non-biting muscids (filth flies) are characterised by the habit of visiting manure or rotting organic material to Seed and/or oviposit. As these flies also often have close associations with human beings, as well as human habitations and domestic animals, they are potentially both a nuisance...

  7. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... and nail care Nail care Nail biting "); (function () { var a = "", b = [ "adid=aad-aad-1", "site=ehs. ... t", "hpos=l", "zone=public", "mcat1=de12", ]; for (var c = 0; c "); (function () { var a = "", b = [ "adid= ...

  8. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Private payer Medicare physician payment MACRA implementation Alternative payment models Fee schedule State policy State policy and action ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care Nail care Nail biting "); (function () { var a = "", b = [ " ...

  9. Friction force experimental approach in High School Physics classes

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Alvarenga Monteiro

    2012-12-01

    Full Text Available http://dx.doi.org/10.5007/2175-7941.2012v29n3p1121 In this paper we propose and describe the performance of an experimental activity to address the concept of friction in High School Physics practical classes. We use a low-cost and simple construction device that enables the determination of the coefficient of static friction between two materials through three different procedures. The results were coherent, with small percentage deviation, which gives reliability to the activity and can stimulate discussions in class. The activity also allows greater contextualization of concepts that are usually discussed only theoretically, requiring a higher abstraction level of the students. This can stimulate discussions and greater interaction between teacher and students.

  10. Fluids with highly directional attractive forces. III. Multiple attraction sites

    International Nuclear Information System (INIS)

    Wertheim, M.S.

    1986-01-01

    The authors derive a reformulation of statistical thermodynamics for fluids of molecules which interact by highly directional attraction. The molecular model consists of a repulsive core and several sites of very short-ranged attraction. The authors explore the relationship between graph cancellation in the fugacity expansion and three types of steric incompatibility between repulsive and attractive interactions involving several molecules. The steric effects are used to best advantage in a limited regrouping of bonds. This controls the density parameters which appear when articulation points are eliminated in the graphical representation. Each density parameter is a singlet density for a species consisting of molecules with a specified set of sites bonded. The densities satisfy subsidiary conditions of internal consistency. These conditions are equivalent to a minimization of the Helmholtz free energy A. Graphical expressions for A and for the pressure are derived. Analogs of the s-particle direct correlation functions and of the Ornstein-Zernike equation are found

  11. Snake-bite-induced Acute Kidney Injury

    International Nuclear Information System (INIS)

    Naqvi, R.

    2016-01-01

    Objective: To describe the clinical spectrum and outcome of patients presenting to a tertiary care kidney center, developing acute kidney injury (AKI) after snake-bite. Study Design: An observational study. Place and Duration of Study: Nephrology Department, Sindh Institute of Urology and Transplantation (SIUT), Karachi, from January 1990 to December 2014. Methodology: All patients coming to SIUT identified as having AKI after snake-bite during the study period were included. AKI was defined according to RIFLE criteria with sudden rise in creatinine or decline in urine output or both. Demographics, clinical presentation, laboratory profile, and final outcome was noted. Result: During the studied period, 115 cases of AKI, secondary to snake-bite, were registered at this institution. Median age of patients was 35.92 ±15.04 (range: 6 - 70) years and male to female ratio was 1.6:1. Time from bite and referral to this hospital ranged from 2 to 28 days (mean: 8.77 ±5.58 days). Oligo-anuria was the most common presentation, being found in 98 (93.90 percentage) patients. Bleeding diathesis was reported in 75 (65.21 percentage) patients on presentation. All patients had normal sized, non-obstructed kidneys on ultrasonography, with no previous comorbids. Renal replacement therapy (RRT) was required in 106 (92.17 percentage) patients. Complete recovery was seen in 59 (51.30 percentage), while 15 (13.04 percentage) patients expired during acute phase of illness, 4 (3.47 percentage) developed CKD, 11 (9.56 percentage) required dialysis beyond 90 days, and 26 (22.60 percentage) were lost to long-term follow-up. Conclusion: Snake-bite, leading to multiple complications including renal failure and death, is a major health issue in tropical countries. Late referral of these patients to specialized centres Result in undesirable outcome. (author)

  12. Dynamic forces on agglomerated particles caused by high-intensity ultrasound.

    Science.gov (United States)

    Knoop, Claas; Fritsching, Udo

    2014-03-01

    In this paper the acoustic forces on particles and agglomerates caused by high-intensity ultrasound in gaseous atmosphere are derived by means of computational fluid dynamics (CFD). Sound induced forces cause an oscillating stress scenario where the primary particles of an agglomerate are alternatingly pressed together and torn apart with the frequency of the applied wave. A comparison of the calculated acoustic forces with respect to the inter particle adhesion forces from Van-der-Waals and liquid bridge interactions reveals that the separation forces may reach the same order of magnitude for 80 μm sized SiO2-particles. Hence, with finite probability acoustically agitated gases may de-agglomerate/disperse solid agglomerate structures. This effect is confirmed by dispersion experiments in an acoustic particle levitation setup. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Bite marks on skin and clay: A comparative analysis

    Directory of Open Access Journals (Sweden)

    R.K. Gorea

    2014-12-01

    Full Text Available Bite marks are always unique because teeth are distinctive. Bite marks are often observed at the crime scene in sexual and in physical assault cases on the skin of the victims and sometimes on edible leftovers in burglary cases. This piece of evidence is often ignored, but if properly harvested and investigated, bite marks may prove useful in apprehending and successfully prosecuting the criminals. Due to the importance of bite marks, we conducted a progressive randomised experimental study conducted on volunteers. A total of 188 bite marks on clay were studied. Based on these findings, 93.34% of the volunteers could be identified from the bite marks on the clay. In addition, 201 impressions on skin were studied, and out of these cases, 41.01% of the same volunteers could be identified based on the bite mark impressions on the skin.

  14. The North-South divide in snake bite envenomation in India

    Directory of Open Access Journals (Sweden)

    Vivek Chauhan

    2016-01-01

    Full Text Available Snake bite envenomations are common in rural areas and the incidence peaks during monsoons in India. Prominent venomous species have been traditionally labeled as the ′big four′ that includes Cobra, Krait, Russel′s viper and Saw scaled viper. Systematic attempts for identification and classification of prevalent snakes in various states of India are missing till now and there is no concrete data on this aspect. The published literature however shows that some species of snakes are more prevalent in a particular region than the other parts of India e.g. Saw scaled vipers in Rajasthan. We reviewed the published literature from various parts of India and found that there is a North-South divide in the snake bite profile from India. Neurotoxic envenomations are significantly higher in North India compared to South India where Hematotoxic envenomations are prevalent. Russel′s viper causes local necrosis, gangrene and compartment syndrome. These manifestations have never been reported in North Indian snake bite profile in the published literature. Early morning neuroparalysis caused by Krait is a common problem in North India leading to high mortality after snake bite. This review presents supporting evidence for the North-South divide and proposes a way forward in formulation and revision of guidelines for snake bite in India.

  15. CLINICO-EPIDEMIOLOGY AND THERAPEUTIC OUTCOME OF SNAKE BITE IN KONASEEMA REGION OF ANDHRA PRADESH

    Directory of Open Access Journals (Sweden)

    Sai Krishna

    2016-03-01

    Full Text Available INTRODUCTION Snake bite is a common and frequently devastating environmental and occupational problem, especially in rural areas of tropical developing countries. Snake bite incidence is high in Andhra Pradesh. With the onset of monsoon the incidence of snake bite used to increase. METHODS Present study is a retrospective study in which all the data of snake bite cases admitted in the Konaseema Institute of Medical Sciences was collected in last two years; details of the patient was obtained from bed head ticket. RESULTS In two years of data collection, 46 snake bite cases are found as per our record. Out of 46 patients, twenty seven were male and nineteen were female. Maximum twenty two (22 patients were between ages 20 to 40 years. Out of forty six patients, forty four recovered and only two patients died, cause of death was acute pulmonary oedema with cardiac arrhythmia. DISCUSSION Most of the patients were given ASV (anti-snake venom, out of that only four patients developed reaction to ASV. Most of the patients who have received ASV were recovered. Only two deaths were reported which was due to acute pulmonary oedema with cardiac arrhythmia. CONCLUSION Awareness and education about snake is required.

  16. Factors related to stability following the surgical correction of skeletal open bite.

    Science.gov (United States)

    Ito, Goshi; Koh, Myongsun; Fujita, Tadashi; Shirakura, Maya; Ueda, Hiroshi; Tanne, Kazuo

    2014-05-01

    If a skeletal anterior open bite malocclusion is treated by orthognathic surgery directed only at the mandible, the lower jaw is repositioned upward in a counter-clockwise rotation. However, this procedure has a high risk of relapse. In the present study, the key factors associated with post-surgical stability of corrected skeletal anterior open bite malocclusions were investigated. Eighteen orthognathic patients were subjected to cephalometric analysis to assess the dental and skeletal changes following mandibular surgery for the correction of an anterior open bite. The patients were divided into two groups, determined by an increase or decrease in nasion-menton (N-Me) distance as a consequence of surgery. Changes in overbite, the displacements of molars and positional changes in Menton were evaluated immediately before and after surgery and after a minimum of one year post-operatively. The group with a decreased N-Me distance exhibited a significantly greater backward positioning of the mandible. The group with an increased N-Me distance experienced significantly greater dentoalveolar extrusion of the lower molars. A sufficient mandibular backward repositioning is an effective technique in the prevention of open bite relapse. In addition, it is important not to induce molar extrusion during post-surgical orthodontic treatment to preserve stability of the surgical open bite correction.

  17. Prototyping of a highly performant and integrated piezoresistive force sensor for microscale applications

    International Nuclear Information System (INIS)

    Komati, Bilal; Agnus, Joël; Clévy, Cédric; Lutz, Philippe

    2014-01-01

    In this paper, the prototyping of a new piezoresistive microforce sensor is presented. An original design taking advantage of both the mechanical and bulk piezoresistive properties of silicon is presented, which enables the easy fabrication of a very small, large-range, high-sensitivity with high integration potential sensor. The sensor is made of two silicon strain gauges for which widespread and known microfabrication processes are used. The strain gauges present a high gauge factor which allows a good sensitivity of this force sensor. The dimensions of this sensor are 700 μm in length, 100 μm in width and 12 μm in thickness. These dimensions make its use convenient with many microscale applications, notably its integration in a microgripper. The fabricated sensor is calibrated using an industrial force sensor. The design, microfabrication process and performances of the fabricated piezoresistive force sensor are innovative thanks to its resolution of 100 nN and its measurement range of 2 mN. This force sensor also presents a high signal-to-noise ratio, typically 50 dB when a 2 mN force is applied at the tip of the force sensor. (paper)

  18. A prospective study on the incidence of dog bites and management in a rural Cambodian, rabies-endemic setting.

    Science.gov (United States)

    Ponsich, Aurelia; Goutard, Flavie; Sorn, San; Tarantola, Arnaud

    2016-08-01

    Rabies circulates intensely in Cambodia, mainly affecting rural populations. We conducted a prospective study to estimate the baseline incidence of potentially infective dog bites in rural villages of Siem Reap province, Cambodia. The study was conducted in a convenience sample of 844 families totaling 1779 persons in four villages. The study collected data in a total of 802.3 person-years. Trained village health workers (VHW) exhaustively documented consecutive dog bites at the end of each month. Between May 15th and November 15th, 2011, a total of 40 attacks (43 bites; 1.07 bites per attack) were notified by 39 persons (50% female; one suffered two distinct incidents) to VHW. The all-age attack rate for bites over this 6-month period was 2.3% (CI95%: 1.7-3.1%), with a global incidence rate estimated at 4.84 bites/100 person-years (CI95%: 3.5-6.6). The mean age in bite victims was 20.8±18.9years (median 12.5; interquartile range 6-36; range 1-63). The dog was identified in 39 (97.5%) of cases, being the household dog in 9 (22.5%) of cases. Bites were classified as severe (WHO Category III-broken skin with bleeding) in 33 (82.5%) of cases with a severe dog bites incidence estimated at 4/100 person-years (CI95%: 2.8-5.6). The bites involved the hand or face in 1 (2.5%) case each (both Category III). In 20 incidents (50%), only rice was applied to the wounds. There were no suspected or confirmed human rabies deaths during the study period but one dog died after biting (2 others were lost to follow-up and 14 were put down by their owner). Our study documented an extremely high incidence of dog bites in of rural Cambodian adults and children. Adapted control policies for canine vaccination are urgently needed. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Evaluation of occlusal forces in different stages of children - An exploratory study

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2018-01-01

    Conclusions: There was a difference in the occlusal bite force at different dentition stages. It was significantly higher in males and in the permanent dentition stage. Height and weight can be considered as predictors of occlusal bite force in older children with permanent dentition.

  20. Axial Force Analysis and Roll Contour Configuration of Four-High CVC Mill

    Directory of Open Access Journals (Sweden)

    Guang-ming Liu

    2018-01-01

    Full Text Available In order to analyze the influence of technical parameters on work roll axial force of four-high continuous variable crown (CVC mill, the deformation analyzing model with top roll system and strip was established based on influence function method. Then a CVC work roll curve designing scheme was proposed and it was carried out on some cold rolling mill considering the requirement of comprehensive work roll axial force minimization. The status of comprehensive work roll axial force is improved considering the rolling schedule that is beneficial to the roller bearing. Corresponding to the newly designed work roll contour, the backup roll end chamfer was designed considering comprehensive performance of interroll stress concentration, comprehensive work roll axial force, and strip shape control ability. The distribution of roll wear with newly designed backup roll contour is more even according to the field application data. The newly established roll configuration scheme is beneficial to four-high CVC mill.

  1. Numerical evaluation of electromagnetic force induced in high Tc superconductor with grain boundary

    International Nuclear Information System (INIS)

    Hashizume, Hidetoshi; Toda, Saburo; Maeda, Koutaro

    1996-01-01

    After high T c superconducting material was discovered, its superconducting characteristic has been improved so that its critical current density becomes comparable with that of metal alloy superconductors. Together with this progress of the high T c material, it is considered to apply the materials to generating levitation force in combination with permanent magnets. In this case, it becomes very important to evaluate quantitatively the electromagnetic force for designing of the devices. Some researches have used numerical analysis to evaluate the force, where the grain boundary was ignored or treated as nonconducting. In the real materials, however, some part of the screening current can pass through the grain boundary. In this paper, therefore, two dimensional electromagnetic analysis was performed with a new method to treat the grain boundaries, and its effect on the levitation force was discussed

  2. Flange joint system for SRF cavities utilizing high force spring clamps for low particle generation

    Science.gov (United States)

    None

    2017-09-05

    A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprung dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.

  3. Puff and bite: the relationship between the glucocorticoid stress response and anti-predator performance in checkered puffer (Sphoeroides testudineus).

    Science.gov (United States)

    Cull, Felicia; O'Connor, Constance M; Suski, Cory D; Shultz, Aaron D; Danylchuk, Andy J; Cooke, Steven J

    2015-04-01

    Individual variation in the endocrine stress response has been linked to survival and performance in a variety of species. Here, we evaluate the relationship between the endocrine stress response and anti-predator behaviors in wild checkered puffers (Sphoeroides testudineus) captured at Eleuthera Island, Bahamas. The checkered puffer has a unique and easily measurable predator avoidance strategy, which is to inflate or 'puff' to deter potential predators. In this study, we measured baseline and stress-induced circulating glucocorticoid levels, as well as bite force, a performance measure that is relevant to both feeding and predator defence, and 'puff' performance. We found that puff performance and bite force were consistent within individuals, but generally decreased following a standardized stressor. Larger puffers were able to generate a higher bite force, and larger puffers were able to maintain a more robust puff performance following a standardized stressor relative to smaller puffers. In terms of the relationship between the glucocorticoid stress response and performance metrics, we found no relationship between post-stress glucocorticoid levels and either puff performance or bite force. However, we did find that baseline glucocorticoid levels predicted the ability of a puffer to maintain a robust puff response following a repeated stressor, and this relationship was more pronounced in larger individuals. Our work provides a novel example of how baseline glucocorticoids can predict a fitness-related anti-predator behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Effect of parameters of a high-temperature superconductor levitation system on the lateral force

    International Nuclear Information System (INIS)

    Yang Yong; Zheng Xiaojing

    2008-01-01

    The lateral forces on a rectangular permanent magnet above a cylindrical high-temperature superconductor during lateral traverses are simulated in two cooling conditions. The simulation is based on the finite element method and critical state model of Bean. The calculations agree well with the previous experimental data, on the basis of which the effect of initial cooling conditions, physical parameters, levitating height during lateral traverses and geometrical parameters on the lateral force is presented

  5. Descriptive study of healthcare professionals’ management of tick bites

    Directory of Open Access Journals (Sweden)

    Eva Buller Viqueira

    2014-02-01

    Full Text Available Introduction Rural primary health centers frequently treat patients with tick bites. This study compares everyday clinical practice at our primary healthcare center to practices recommended by current scientific evidence. Purpose To describe the everyday management of tick bites by different healthcare professionals and to compare this management to evidence-based therapy guidelines. Design Cross-sectional, descriptive observational study. Methods Data was collected through an anonymous self-completed questionnaire. The form was filled out by a consecutive sample of nurses, physicians and pediatricians of the clinical management unit of Medina-Sidonia (Cádiz. Results Most nurses in the sample group use some type of product to facilitate the extraction of the tick (10 of the 11 surveyed nurses, 90.9%. The most frequently used products were chloroethyl and local anesthetic. In addition, nine nurses use gentle traction with tweezers (81.82% to remove the tick. In the physician sample group, 3 out of 12 respondents (25% prescribe antibiotics in all cases and nine stated that they knew which antibiotic should be used as first choice. In both cases, a high number of healthcare providers confirm giving post-extraction advice to patients: 11 in the medical community (91.66% and nine nurses (81.82%. Conclusions We conclude that the performance of the healthcare providers that integrate this study does not closely follow general recommendations for extraction, treatment and follow-up care in patients with tick bites. Therefore, there is a need to improve the level of knowledge to ensure quality care in these instances.

  6. Awareness of rabies and response to dog bites in a Bangladesh community

    DEFF Research Database (Denmark)

    Ghosh, Sumon; Chowdhury, Sukanta; Haider, Najmul

    2016-01-01

    Community awareness regarding rabies and treatment seeking behaviours are critical both for the prevention and control of the disease in human and animals. We conducted a study to explore people's awareness about rabies, their attitudes towards dogs and practices associated with treating dog bites...... in Satkhira Sadar, a south-western sub-district of Bangladesh. Of the total 3200 households (HHs) surveyed, the majority of the respondents have heard about rabies (73%) and there was a high level of awareness that dog bite is the main cause of rabies (86%), and that rabies can be prevented by vaccination (85......%). However, 59% of the dog bite victims first seek treatment from traditional healers instead of visiting the hospitals, 29% received the rabies vaccine, 2% practiced proper wound washing with soap and water, while 4.8% have not taken any measures. None of the victims have received rabies immunoglobulin (RIG...

  7. A High Performance Sensor for Triaxial Cutting Force Measurement in Turning

    Directory of Open Access Journals (Sweden)

    You Zhao

    2015-04-01

    Full Text Available This paper presents a high performance triaxial cutting force sensor with excellent accuracy, favorable natural frequency and acceptable cross-interference for high speed turning process. Octagonal ring is selected as sensitive element of the designed sensor, which is drawn inspiration from ring theory. A novel structure of two mutual-perpendicular octagonal rings is proposed and three Wheatstone full bridge circuits are specially organized in order to obtain triaxial cutting force components and restrain cross-interference. Firstly, the newly developed sensor is tested in static calibration; test results indicate that the sensor possesses outstanding accuracy in the range of 0.38%–0.83%. Secondly, impacting modal tests are conducted to identify the natural frequencies of the sensor in triaxial directions (i.e., 1147 Hz, 1122 Hz and 2035 Hz, which implies that the devised sensor can be used for cutting force measurement in a high speed lathe when the spindle speed does not exceed 17,205 rev/min in continuous cutting condition. Finally, an application of the sensor in turning process is operated to show its performance for real-time cutting force measurement; the measured cutting forces demonstrate a good accordance with the variation of cutting parameters. Thus, the developed sensor possesses perfect properties and it gains great potential for real-time cutting force measurement in turning.

  8. Superhydrophobic gecko feet with high adhesive forces towards water and their bio-inspired materials

    Science.gov (United States)

    Liu, Kesong; Du, Jiexing; Wu, Juntao; Jiang, Lei

    2012-01-01

    Functional integration is an inherent characteristic for multiscale structures of biological materials. In this contribution, we first investigate the liquid-solid adhesive forces between water droplets and superhydrophobic gecko feet using a high-sensitivity micro-electromechanical balance system. It was found, in addition to the well-known solid-solid adhesion, the gecko foot, with a multiscale structure, possesses both superhydrophobic functionality and a high adhesive force towards water. The origin of the high adhesive forces of gecko feet to water could be attributed to the high density nanopillars that contact the water. Inspired by this, polyimide films with gecko-like multiscale structures were constructed by using anodic aluminum oxide templates, exhibiting superhydrophobicity and a strong adhesive force towards water. The static water contact angle is larger than 150° and the adhesive force to water is about 66 μN. The resultant gecko-inspired polyimide film can be used as a ``mechanical hand'' to snatch micro-liter liquids. We expect this work will provide the inspiration to reveal the mechanism of the high-adhesive superhydrophobic of geckos and extend the practical applications of polyimide materials.

  9. The influence of bubbles on the perception carbonation bite.

    Directory of Open Access Journals (Sweden)

    Paul M Wise

    Full Text Available Although many people naively assume that the bite of carbonation is due to tactile stimulation of the oral cavity by bubbles, it has become increasingly clear that carbonation bite comes mainly from formation of carbonic acid in the oral mucosa. In Experiment 1, we asked whether bubbles were in fact required to perceive carbonation bite. Subjects rated oral pungency from several concentrations of carbonated water both at normal atmospheric pressure (at which bubbles could form and at 2.0 atmospheres pressure (at which bubbles did not form. Ratings of carbonation bite under the two pressure conditions were essentially identical, indicating that bubbles are not required for pungency. In Experiment 2, we created controlled streams of air bubbles around the tongue in mildly pungent CO2 solutions to determine how tactile stimulation from bubbles affects carbonation bite. Since innocuous sensations like light touch and cooling often suppress pain, we predicted that bubbles might reduce rated bite. Contrary to prediction, air bubbles flowing around the tongue significantly enhanced rated bite, without inducing perceived bite in blank (un-carbonated solutions. Accordingly, though bubbles are clearly not required for carbonation bite, they may well modulate perceived bite. More generally, the results show that innocuous tactile stimulation can enhance chemogenic pain. Possible physiological mechanisms are discussed.

  10. Annual incidence of snake bite in rural bangladesh.

    Directory of Open Access Journals (Sweden)

    Ridwanur Rahman

    Full Text Available BACKGROUND: Snake bite is a neglected public health problem in the world and one of the major causes of mortality and morbidity in many areas, particularly in the rural tropics. It also poses substantial economic burdens on the snake bite victims due to treatment related expenditure and loss of productivity. An accurate estimate of the risk of snake bite is largely unknown for most countries in the developing world, especially South-East Asia. METHODOLOGY/PRINCIPAL FINDINGS: We undertook a national epidemiological survey to determine the annual incidence density of snake bite among the rural Bangladeshi population. Information on frequency of snake bite and individuals' length of stay in selected households over the preceding twelve months was rigorously collected from the respondents through an interviewer administered questionnaire. Point estimates and confidence intervals of the incidence density of snake bite, weighted and adjusted for the multi-stage cluster sampling design, were obtained. Out of 18,857 study participants, over one year a total of 98 snake bites, including one death were reported in rural Bangladesh. The estimated incidence density of snake bite is 623.4/100,000 person years (95% C I 513.4-789.2/100,000 person years. Biting occurs mostly when individuals are at work. The majority of the victims (71% receive snake bites to their lower extremities. Eighty-six percent of the victims received some form of management within two hours of snake bite, although only three percent of the victims went directly to either a medical doctor or a hospital. CONCLUSIONS/SIGNIFICANCE: Incidence density of snake bite in rural Bangladesh is substantially higher than previously estimated. This is likely due to better ascertainment of the incidence through a population based survey. Poor access to health services increases snake bite related morbidity and mortality; therefore, effective public health actions are warranted.

  11. Evaluation of Snake Bites with Bedside Ultrasonography

    Directory of Open Access Journals (Sweden)

    Josef E Jolissaint

    2018-04-01

    Full Text Available History of present illness: While watering his lawn, a 36-year-old man felt two sharp bites to his bilateral ankles. He reports that he then saw a light brown, 2-foot snake slither away from him. He came to the emergency department because of pain and swelling in his ankles and inability to bear weight. Physical examination revealed bilateral ankle swelling and puncture marks on his left lateral heel and medial right ankle. Palpation, passive flexion and extension elicited severe pain bilaterally. Blood work including prothrombin time (PT, partial thromboplastin time (PTT, international normalized ratio (INR, and fibrinogen were within normal limits. Consultation with Poison Control indicated the snake was likely a copperhead, which is a venomous snake whose bites rarely require antivenin. Significant findings: In this case, ultrasonography of the lateral surface of the left foot revealed soft tissue edema (red arrow and fluid collection (white asterisk adjacent to the extensor tendon (white arrow. The edematous area resembles cobblestones, with hypoechoic areas of fluid spanning relatively hyperechoic fat lobules. The tendon is surrounded by anechoic fluid, expanding the potential space in the sheath. No hyperechoic foreign objects were noted. Discussion: The patient was diagnosed with soft tissue injury and extensor tenosynovitis after a snake envenomation. Snake venom contains metalloproteinases and other enzymatic proteins that cause local tissue edema and necrosis.1 After a snake bite, ultrasound can be used to assess for retained fangs, soft tissue edema, tendon sheath fluid, muscle fasciculation, and injury to deeper musculature that may not be readily apparent on physical exam.2,3 Most patients with tenosynovitis will recover with immobilization of the joint and non-steroidal anti-inflammatory medications.4 Rarely, the tendon may become infected requiring antibiotics and surgical intervention.4 Topics: Ultrasound, snake envenomation

  12. [Surgical management of animal bites in children].

    Science.gov (United States)

    Touzet-Roumazeille, S; Jayyosi, L; Plenier, Y; Guyot, E; Guillard, T; François, C

    2016-10-01

    Children represent a population at risk, because of their short size, their naivety and their attraction to animals. The face and hands are the most specific locations in young children. Wounds are often multiple. In more than half the cases, the child knows the animal, which are dogs and cats by frequency argument. The bite episode occurs mostly when the child is alone with the pet without direct supervision, while playing or stroking the animal. As in all bites, pediatric lesions are infectious, functional and aesthetic emergencies, but the goal of this work was primarily to make a point on principles of surgical management of animal bites in children, highlighting pediatric specificities. Animal bites require psychological, anesthetic and surgical treatment, adapted to the child, in a specialized structure. Hospitalization and general anesthesia are more frequent in children. Any suspicion of mistreatment (and/or abuse) should lead to the child's hospitalization, even if wounds do not justify monitoring in a surgical environment. Emergency surgery is essential to limit functional and aesthetic consequences. The healing capacities of the child and the frequent lack of co-morbidity allow a conservative surgical treatment with suture, repositioning skin flaps and controlled healing in the first place. Immobilization, drainage, and antibiotics will complete the surgery. The healing process, however, leads to a specific management during scar remodeling phase and growth. Psychological care of the child and parents should not be forgotten, and has to start at the same time as surgical treatment at in acute phase. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. High-Performance Flexible Force and Temperature Sensing Array with a Robust Structure

    Science.gov (United States)

    Kim, Min-Seok; Song, Han-Wook; Park, Yon-Kyu

    We have developed a flexible tactile sensor array capable of sensing physical quantities, e.g. force and temperature with high-performances and high spatial resolution. The fabricated tactile sensor consists of 8 × 8 force measuring array with 1 mm spacing and a thin metal (copper) temperature sensor. The flexible force sensing array consists of sub-millimetre-size bar-shaped semi-conductor strain gage array attached to a thin and flexible printed circuit board covered by stretchable elastomeric material on both sides. This design incorporates benefits of both materials; the semi-conductor's high performance and the polymer's mechanical flexibility and robustness, while overcoming their drawbacks of those two materials. Special fabrication processes, so called “dry-transfer technique” have been used to fabricate the tactile sensor along with standard micro-fabrication processes.

  14. Repurposing a Benchtop Centrifuge for High-Throughput Single-Molecule Force Spectroscopy.

    Science.gov (United States)

    Yang, Darren; Wong, Wesley P

    2018-01-01

    We present high-throughput single-molecule manipulation using a benchtop centrifuge, overcoming limitations common in other single-molecule approaches such as high cost, low throughput, technical difficulty, and strict infrastructure requirements. An inexpensive and compact Centrifuge Force Microscope (CFM) adapted to a commercial centrifuge enables use by nonspecialists, and integration with DNA nanoswitches facilitates both reliable measurements and repeated molecular interrogation. Here, we provide detailed protocols for constructing the CFM, creating DNA nanoswitch samples, and carrying out single-molecule force measurements.

  15. Design principles for high-pressure force fields: Aqueous TMAO solutions from ambient to kilobar pressures.

    Science.gov (United States)

    Hölzl, Christoph; Kibies, Patrick; Imoto, Sho; Frach, Roland; Suladze, Saba; Winter, Roland; Marx, Dominik; Horinek, Dominik; Kast, Stefan M

    2016-04-14

    Accurate force fields are one of the major pillars on which successful molecular dynamics simulations of complex biomolecular processes rest. They have been optimized for ambient conditions, whereas high-pressure simulations become increasingly important in pressure perturbation studies, using pressure as an independent thermodynamic variable. Here, we explore the design of non-polarizable force fields tailored to work well in the realm of kilobar pressures--while avoiding complete reparameterization. Our key is to first compute the pressure-induced electronic and structural response of a solute by combining an integral equation approach to include pressure effects on solvent structure with a quantum-chemical treatment of the solute within the embedded cluster reference interaction site model (EC-RISM) framework. Next, the solute's response to compression is taken into account by introducing pressure-dependence into selected parameters of a well-established force field. In our proof-of-principle study, the full machinery is applied to N,N,N-trimethylamine-N-oxide (TMAO) in water being a potent osmolyte that counteracts pressure denaturation. EC-RISM theory is shown to describe well the charge redistribution upon compression of TMAO(aq) to 10 kbar, which is then embodied in force field molecular dynamics by pressure-dependent partial charges. The performance of the high pressure force field is assessed by comparing to experimental and ab initio molecular dynamics data. Beyond its broad usefulness for designing non-polarizable force fields for extreme thermodynamic conditions, a good description of the pressure-response of solutions is highly recommended when constructing and validating polarizable force fields.

  16. First Pediatric Case of Tularemia after a Coyote Bite

    Directory of Open Access Journals (Sweden)

    Bruno B. Chomel

    2016-01-01

    Full Text Available Bite-transmitted tularemia is a rare event in humans and most of the cases have been associated with cat bites. We report the first pediatric case of tularemia caused by a coyote (Canis latrans bite. Coyotes can be healthy carriers of Francisella tularensis and transmit this infectious agent through a bite. Pediatricians should be aware of this risk after a carnivore bite and implement appropriate antibiotic therapy, as amoxicillin/clavulanate potassium (Augmentin may have prolonged the typical two to three days’ incubation period commonly observed for tularemia after an animal bite and was not effective in preventing clinical signs in this child. Finally, it emphasizes again the importance of early and late serum samples for appropriate serodiagnostic.

  17. Open Fracture of the Forearm Bones due to Horse Bite

    OpenAIRE

    Santoshi, John Ashutosh; Leshem, Lall

    2014-01-01

    Introduction: Fractures have been described mainly following falling accidents in horse-related injuries. Horse bites are uncommon accidents. We present a case of open fracture of the forearm due to horse bite. Case Report: A 35-year-old male farm-worker presented to the emergency room with alleged history of horse bite to the right forearm about 2 hours prior to presentation while feeding the horse. There was deformity of the forearm with multiple puncture wounds, deep abrasions and small...

  18. Enhanced performance in capacitive force sensors using carbon nanotube/polydimethylsiloxane nanocomposites with high dielectric properties

    Science.gov (United States)

    Jang, Hyeyoung; Yoon, Hyungsuk; Ko, Youngpyo; Choi, Jaeyoo; Lee, Sang-Soo; Jeon, Insu; Kim, Jong-Ho; Kim, Heesuk

    2016-03-01

    Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased dielectric properties of elastomers and simple sensor structure. We rationally design dielectric elastomers based on alkylamine modified-multi-walled carbon nanotube (MWCNT)/polydimethylsiloxane (PDMS) composites, which have a higher dielectric constant than pure PDMS. The alkylamine-MWCNTs show excellent dispersion in a PDMS matrix, thus leading to enhanced and reliable dielectric properties of the composites. A force sensor array fabricated with alkylamine-MWCNT/PDMS composites presents an enhanced response due to the higher dielectric constant of the composites than that of pure PDMS. This study is the first to report enhanced performance of capacitive force sensors by modulating the dielectric properties of elastomers. We believe that the disclosed strategy to improve the sensor performance by increasing the dielectric properties of elastomers has great potential in the development of capacitive force sensor arrays that respond to various input forces.Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased

  19. An evaluation of rabies vaccination rates among canines and felines involved in biting incidents within the Wellington-Dufferin-Guelph Public Health Department.

    Science.gov (United States)

    Bottoms, K; Trotz-Williams, L; Hutchison, S; MacLeod, J; Dixon, J; Berke, O; Poljak, Z

    2014-11-01

    The objectives of this study were to determine the rate of animal bite incidents occurring in the human population of a local health department, and to determine the proportion of these canines and felines that were not up to date on their rabies vaccination at the time the incident occurred. Data were obtained from animal bite incidents reported to Wellington-Dufferin-Guelph Public Health during 2010 and 2011. Descriptive statistics of 718 eligible reports revealed the average rate of animal biting was 1.55 bites per 1000 residents per year. Approximately 54% of these animals were vaccinated against rabies, 32% were not up to date with their rabies vaccination, and the remaining 14.5% were of unknown status. The unit of analysis was the municipality, and the four outcomes of interest were: (i) number of animal bite incidents per 1000 residents, (ii) number of dog bite incidents per 1000 residents, (iii) proportion of animals involved in bite incidents that were not up to date with their rabies vaccination, and (iv) proportion of dogs that were not up to date. Associations between the outcomes and selected demographic variables were investigated using regression analysis. The number of veterinary clinics per 10,000 residents, and whether the municipality was urban or rural were identified as significant predictors for the number of animal bites per 1000 residents, and the number of dog bites. There were no significant predictors for the proportion of unvaccinated animals or dogs. Spatial clustering and the location of spatial clusters were assessed using the empirical Bayes index and spatial scan test. This analysis identified five municipalities within the health department that have a high rate of biting incidents and a high proportion of animals that were not up to date on their rabies vaccination. Such municipalities are ideal for targeted educational campaigns regarding the importance of vaccination in pets. © 2014 Blackwell Verlag GmbH.

  20. Management of Poisonous Snake Bites in Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Kao-Ping Chang

    2007-10-01

    Full Text Available Snake bite envenomation is not uncommon in Taiwan. This study focuses on the pattern of poisonous snake bites and their management in southern Taiwan over a 5-year period. The case histories of 37 patients with poisonous snake bites admitted to the Kaohsiung Medical University Hospital between June 2001 and July 2005 were analyzed retrospectively. Three patients, bitten by unknown species of venomous snakes, were excluded from this study. The frequency of snake bites from each species of snake, the local and systemic manifestations of snake bite, treatment of complications and final outcomes were analyzed. Of the remaining 34 patients, 11 (32.4% were bitten by bamboo vipers, 10 (29.4% by Russell's pit vipers, 8 (23.5% by Taiwan cobras and 5 (14.7% by Taiwan Habu. The majority of snake bites (28 occurred between May and November. Those affected were mainly outdoor hikers (14 and workers (9. The antivenin requirements for treatment in the emergency room were in accordance with standard procedures. No mortality was noted among those envenomed by poisonous snakes. Although poisonous snake bite is not a common life-threatening emergency in the study area, we observed both an environmental risk and a seasonal incidence of snake bite. Keeping the varied clinical manifestations of snake bite in mind is important for effective management. Ready availability and appropriate use of antivenin, close monitoring of patients, institution of ventilatory support and early referral to a larger hospital when required, all help reduce mortality.

  1. High-resolution and large dynamic range nanomechanical mapping in tapping-mode atomic force microscopy

    International Nuclear Information System (INIS)

    Sahin, Ozgur; Erina, Natalia

    2008-01-01

    High spatial resolution imaging of material properties is an important task for the continued development of nanomaterials and studies of biological systems. Time-varying interaction forces between the vibrating tip and the sample in a tapping-mode atomic force microscope contain detailed information about the elastic, adhesive, and dissipative response of the sample. We report real-time measurement and analysis of the time-varying tip-sample interaction forces with recently introduced torsional harmonic cantilevers. With these measurements, high-resolution maps of elastic modulus, adhesion force, energy dissipation, and topography are generated simultaneously in a single scan. With peak tapping forces as low as 0.6 nN, we demonstrate measurements on blended polymers and self-assembled molecular architectures with feature sizes at 1, 10, and 500 nm. We also observed an elastic modulus measurement range of four orders of magnitude (1 MPa to 10 GPa) for a single cantilever under identical feedback conditions, which can be particularly useful for analyzing heterogeneous samples with largely different material components.

  2. Faraday forcing of high-temperature levitated liquid metal drops for the measurement of surface tension.

    Science.gov (United States)

    Brosius, Nevin; Ward, Kevin; Matsumoto, Satoshi; SanSoucie, Michael; Narayanan, Ranga

    2018-01-01

    In this work, a method for the measurement of surface tension using continuous periodic forcing is presented. To reduce gravitational effects, samples are electrostatically levitated prior to forcing. The method, called Faraday forcing, is particularly well suited for fluids that require high temperature measurements such as liquid metals where conventional surface tension measurement methods are not possible. It offers distinct advantages over the conventional pulse-decay analysis method when the sample viscosity is high or the levitation feedback control system is noisy. In the current method, levitated drops are continuously translated about a mean position at a small, constant forcing amplitude over a range of frequencies. At a particular frequency in this range, the drop suddenly enters a state of resonance, which is confirmed by large executions of prolate/oblate deformations about the mean spherical shape. The arrival at this resonant condition is a signature that the parametric forcing frequency is equal to the drop's natural frequency, the latter being a known function of surface tension. A description of the experimental procedure is presented. A proof of concept is given using pure Zr and a Ti 39.5 Zr 39.5 Ni 21 alloy as examples. The results compare favorably with accepted literature values obtained using the pulse-decay method.

  3. Nanomagnets with high shape anisotropy and strong crystalline anisotropy: perspectives on magnetic force microscopy

    International Nuclear Information System (INIS)

    Campanella, H; Llobet, J; Esteve, J; Plaza, J A; Jaafar, M; Vázquez, M; Asenjo, A; Del Real, R P

    2011-01-01

    We report on a new approach for magnetic imaging, highly sensitive even in the presence of external, strong magnetic fields. Based on FIB-assisted fabricated high-aspect-ratio rare-earth nanomagnets, we produce groundbreaking magnetic force tips with hard magnetic character where we combine a high aspect ratio (shape anisotropy) together with strong crystalline anisotropy (rare-earth-based alloys). Rare-earth hard nanomagnets are then FIB-integrated to silicon microcantilevers as highly sharpened tips for high-field magnetic imaging applications. Force resolution and domain reversing and recovery capabilities are at least one order of magnitude better than for conventional magnetic tips. This work opens new, pioneering research fields on the surface magnetization process of nanostructures based either on relatively hard magnetic materials—used in magnetic storage media—or on materials like superparamagnetic particles, ferro/antiferromagnetic structures or paramagnetic materials.

  4. Magnetic force microscopy of thin film media for high density magnetic recording

    NARCIS (Netherlands)

    Porthun, Steffen; Porthun, S.; Abelmann, Leon; Lodder, J.C.

    1998-01-01

    This paper discusses various aspect of magnetic force microscopy (MFM) for use in the field of high density magnetic recording. After an introduction of the most important magnetic imaging techniques, an overview is given of the operation and theory of MFM. The developments in instrumentation, MFM

  5. Measurement of Levitation Forces of High-"T[subscript c] Superconductors

    Science.gov (United States)

    Becker, M.; Koblischka, M. R.; Hartmann, U.

    2010-01-01

    We show the construction of a so-called levitation balance which is capable of measuring the levitation forces between a permanent magnet and a superconducting high-T[subscript c] thin film sample. The underlying theoretical basis is discussed in detail. The experiment is performed as an introductory physics experiment for school students as well…

  6. A qualitative investigation of the perceptions of female dog-bite victims and implications for the prevention of dog bites

    OpenAIRE

    Westgarth, Carri; Watkins, Francine

    2015-01-01

    Preventing dog bites is an increasingly important public health and political issue with implications for both human and animal health and welfare. Expert opinion is that most bites are preventable. Intervention materials have been designed to educate people on how to assess the body language of dogs, evaluate risk, and take appropriate action. The effectiveness of this approach is rarely evaluated and the incidence of dog bites is thought to be increasing. Is the traditional approach to dog ...

  7. Levitation force and magnetization in bulk and thin film high Tc superconductors

    International Nuclear Information System (INIS)

    Riise, A.B

    1998-04-01

    The authors present high-resolution measurements of the repulsive vertical force and its associated stiffness between a Nd-B-Fe magnet and a YBa 2 Cu 3 O 7-δ superconductor in cylindrical geometry. The results are compared with theoretical predictions. The calculations are based on a model in which the superconductor is assumed to be either a sintered granular material or consisting of grains embedded in a nonactive matrix so that only intragranular currents are important. The critical state model is applied to each grain individually and closed form expressions for both vertical force F z and stiffness are obtained in a configuration with cylindrical symmetry. The model explains all features of the experimental results in a consistent way. A good quantitative agreement has been obtained using only three adjustable parameters. Several central aspects of the phenomenon of magnetic levitation with high-T c superconductors are presented. High-resolution measurements are made of the repulsive vertical force and its associated stiffness as well as the horizontal stabilizing force and the stiffness governing lateral vibrations. The results obtained at 77 K using a granular YBa 2 Cu 3 O 7-δ sample and Nd-Fe-B magnet in a rectangular levitation configuration are compared with theoretical predictions. The calculations, which are based on the critical state model with the assumption that it applies to the grins individually, give closed-form expressions for all the measured quantities. It is concluded that the present model explains all features of the observations in a consistent way. Using only three adjustable parameters a good agreement exists also at a quantitative level. Experimental studies and theoretical modelling of the levitation force on a permanent magnet placed above a superconducting thin film are offered. It is shown that measurements of the levitation force is a simple and precise method to determine the critical current density in thin films

  8. Levitation force and magnetization in bulk and thin film high T{sub c} superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Riise, A.B

    1998-04-01

    The authors present high-resolution measurements of the repulsive vertical force and its associated stiffness between a Nd-B-Fe magnet and a YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} superconductor in cylindrical geometry. The results are compared with theoretical predictions. The calculations are based on a model in which the superconductor is assumed to be either a sintered granular material or consisting of grains embedded in a nonactive matrix so that only intragranular currents are important. The critical state model is applied to each grain individually and closed form expressions for both vertical force F{sub z} and stiffness are obtained in a configuration with cylindrical symmetry. The model explains all features of the experimental results in a consistent way. A good quantitative agreement has been obtained using only three adjustable parameters. Several central aspects of the phenomenon of magnetic levitation with high-T{sub c} superconductors are presented. High-resolution measurements are made of the repulsive vertical force and its associated stiffness as well as the horizontal stabilizing force and the stiffness governing lateral vibrations. The results obtained at 77 K using a granular YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} sample and Nd-Fe-B magnet in a rectangular levitation configuration are compared with theoretical predictions. The calculations, which are based on the critical state model with the assumption that it applies to the grins individually, give closed-form expressions for all the measured quantities. It is concluded that the present model explains all features of the observations in a consistent way. Using only three adjustable parameters a good agreement exists also at a quantitative level. Experimental studies and theoretical modelling of the levitation force on a permanent magnet placed above a superconducting thin film are offered. It is shown that measurements of the levitation force is a simple and precise method to determine the

  9. Improvement of force factor of magnetostrictive vibration power generator for high efficiency

    International Nuclear Information System (INIS)

    Kita, Shota; Ueno, Toshiyuki; Yamada, Sotoshi

    2015-01-01

    We develop high power magnetostrictive vibration power generator for battery-free wireless electronics. The generator is based on a cantilever of parallel beam structure consisting of coil-wound Galfenol and stainless plates with permanent magnet for bias. Oscillating force exerted on the tip bends the cantilever in vibration yields stress variation of Galfenol plate, which causes flux variation and generates voltage on coil due to the law of induction. This generator has advantages over conventional, such as piezoelectric or moving magnet types, in the point of high efficiency, highly robust, and low electrical impedance. Our concern is the improvement of energy conversion efficiency dependent on the dimension. Especially, force factor, the conversion ratio of the electromotive force (voltage) on the tip velocity in vibration, has an important role in energy conversion process. First, the theoretical value of the force factor is formulated and then the validity was verified by experiments, where we compare four types of prototype with parameters of the dimension using 7.0 × 1.5 × 50 mm beams of Galfenol with 1606-turn wound coil. In addition, the energy conversion efficiency of the prototypes depending on load resistance was measured. The most efficient prototype exhibits the maximum instantaneous power of 0.73 W and energy of 4.7 mJ at a free vibration of frequency of 202 Hz in the case of applied force is 25 N. Further, it was found that energy conversion efficiency depends not only on the force factor but also on the damping (mechanical loss) of the vibration

  10. Superhydrophobic Zr-based metallic glass surface with high adhesive force

    Science.gov (United States)

    Li, Ning; Xia, Ting; Heng, Liping; Liu, Lin

    2013-06-01

    Micro/nano hierarchical structures were constructed on Zr35Ti30Be26.75Cu8.25 metallic glass surface by silicon moulding and subsequently chemical etching. The as-formed surface exhibited both superhydrophobicity and high adhesive force towards water. The superhydrophobicity is rationalized based on the modified Cassie-Baxter model [A. B. D. Cassie and S. Baxter, Trans. Faraday Soc. 40, 546 (1944)]. The origin of the robust adhesion is described in terms of intermolecular capillary forces. The present results not only provide a method to fabricate superhydrophobic metallic glasses surface but also explore an important industrial application as dry adhesives and transport of liquid microdroplets.

  11. Genome-wide association study of insect bite hypersensitivity in two horse populations in the Netherlands

    NARCIS (Netherlands)

    Schurink, A.; Wolc, A.; Ducro, B.J.; Frankena, K.; Garrick, D.J.; Dekkers, J.C.M.; Arendonk, van J.A.M.

    2012-01-01

    Background: Insect bite hypersensitivity is a common allergic disease in horse populations worldwide. Insect bite hypersensitivity is affected by both environmental and genetic factors. However, little is known about genes contributing to the genetic variance associated with insect bite

  12. Functional morphology and biomechanics of the tongue-bite apparatus in salmonid and osteoglossomorph fishes

    Science.gov (United States)

    Camp, Ariel L; Konow, Nicolai; Sanford, Christopher P J

    2009-01-01

    The tongue-bite apparatus and its associated musculoskeletal elements of the pectoral girdle and neurocranium form the structural basis of raking, a unique prey-processing behaviour in salmonid and osteoglossomorph fishes. Using a quantitative approach, the functional osteology and myology of this system were compared between representatives of each lineage, i.e. the salmonid Salvelinus fontinalis (N =10) and the osteoglossomorph Chitala ornata(N = 8). Divergence was found in the morphology of the novel cleithrobranchial ligament, which potentially relates to kinematic differences between the raking lineage representatives. Salvelinus had greater anatomical cross-sectional areas of the epaxial, hypaxial and protractor hyoideus muscles, whereas Chitala had greater sternohyoideus and adductor mandibulae mass. Two osteology-based biomechanical models (a third-order lever for neurocranial elevation and a modified four-bar linkage for hyoid retraction) showed divergent force/velocity priorities in the study taxa. Salvelinus maximizes both force (via powerful cranial muscles) and velocity (through mechanical amplification) during raking. In contrast, Chitala has relatively low muscle force but more efficient force transmission through both mechanisms compared with Salvelinus. It remains unclear if and how behavioural modulation and specializations in the post-cranial anatomy may affect the force/velocity trade-offs in Chitala. Further studies of tongue-bite apparatus morphology and biomechanics in a broader species range may help to clarify the role that osteology and myology play in the evolution of behavioural diversity. PMID:19438765

  13. The evaluation on clamping force of high strength bolts by length parameter

    International Nuclear Information System (INIS)

    Kim, Kang-Seok; Nah, Hwan-Seon; Lee, Hyeon-Ju; Lee, Kang-Min

    2009-01-01

    It has been reported that the length parameter of high strength bolts results in the variance in tension loads. The required turn for each length is specified in AISC RCSC specification. This study was focused on evaluating any influence on the clamping torque subjected to length parameter of high strength bolts. The two kinds of high strength bolts of specimen are as follows; High Strength Hexagon bolt defined on ASTM A490 and Torque Shear Bolt on KS B 2819. The length parameter ranged from 60mm(3d) to 140mm(7d). The torque, turn of nut and the clamping force were analyzed to review whether length parameter can be affected on the required tension load. To test whether the length parameter has an impact on the torque and turn of nut for the required strength and clamping force, statistical analysis is carried out. (author)

  14. High-speed atomic force microscopy combined with inverted optical microscopy for studying cellular events.

    OpenAIRE

    Suzuki, Yuki; Sakai, Nobuaki; Yoshida, Aiko; Uekusa, Yoshitsugu; Yagi, Akira; Imaoka, Yuka; Ito, Shuichi; Karaki, Koichi; Takeyasu, Kunio

    2013-01-01

    A hybrid atomic force microscopy (AFM)-optical fluorescence microscopy is a powerful tool for investigating cellular morphologies and events. However, the slow data acquisition rates of the conventional AFM unit of the hybrid system limit the visualization of structural changes during cellular events. Therefore, high-speed AFM units equipped with an optical/fluorescence detection device have been a long-standing wish. Here we describe the implementation of high-speed AFM coupled with an optic...

  15. Perawatan Maloklusi Angle Klas I dengan Gigi Depan Crowding Berat dan Cross Bite Menggunakan Teknik Begg pada Pasien dengan Kebersihan Mulut Buruk

    Directory of Open Access Journals (Sweden)

    Sri Wahyuningsih

    2014-12-01

    Full Text Available Gigi depan crowding/berjejal parah dan cross bite adalah kasus yang sering dijumpai pada perawatan ortodontik. Gigi crowding dapat menyulitkan membersihkan mulut pada area gigi crowding sehingga dapat menyebabkan masalah periodontal. Salah satu keuntungan perawatan ortodontik cekat dengan teknik Begg adalah menghasilkan gaya yang ringan dalam megkoreksi gigi berjejal dan cross bite dapat memberikan kenyamanan pada pasien. Tujuan perawatan ini adalah untuk mengkoreksi gigi berjejal dan cross bite dalam waktu yang singkat menggunakan teknik Begg. Seorang pasien wanita umur 24 tahun dengan maloklusi Angle klas I dan skeletal klas III protrusif mandibula, gigi depan crowding berat dan cross bite, konstraksi lengkung pada kedua rahang, pergeseran median line rahang atas dan bawah disertai, gingivitis berat dan karies. Skaling, perawatan saluran akar dan pencabutan gigi non vital dilakukan sebelum perawatan ortodontik dilakukan. Koreksi dengan teknik Begg memerlukan waktu selama 6 bulan untuk mengkoreksi gigi crowding dan cross bite semuanya dalam waktu yang sama. Koreksi kasus gigi depan crowding berat dan cross bite disertai masalah periodontal dapat dilakukan dengan teknik Begg dalam waktu yang singkat dengan kemajuan yang bagus.   Treatment of Class I Angle Malocclusion with Severe Crowding and Crossbite of Anterior Teeth Using Begg Technique in Bad Oral Hygiene Patient. The severe crowding and cross bite of anterior teeth were very common type cases in orthodontic. Crowding teeth compromised the oral hygiene due to the difficulty in oral cleansing on the crowding area that cause periodontal problem. One of advantages of fixed orthodontic treatment using Begg technique produced the light forces in correcting crowding and cross bite could give convenience to patients. The purpose of this treatment is to correct crowding and cross bite in a short period of time using Begg technique. A 24 years old female patient with Class I Angle

  16. End effect braking force reduction in high-speed single-sided linear induction machine

    International Nuclear Information System (INIS)

    Shiri, Abbas; Shoulaie, Abbas

    2012-01-01

    Highlights: ► A new analytical equation to model the end effect braking force of SLIM is derived. ► Equations for efficiency, power factor and output thrust are analytically derived. ► The effect of design variables on the performance of the motor is analyzed. ► An optimization method is employed to minimize the end effect braking force (EEBF). ► The results show that EEBF is minimized by appropriate selection of motor parameters. - Abstract: Linear induction motors have been widely employed in industry because of their simple structure and low construction cost. However, they suffer from low efficiency and power factor. In addition, existence of so called end effect influences their performance especially in high speeds. The end effect deteriorates the performance of the motor by producing braking force. So, in this paper, by using Duncan equivalent circuit model, a new analytical equation is proposed to model end effect braking force. Employing the proposed equation and considering all phenomena involved in the single-sided linear induction motor, a simple design procedure is presented and the effect of different design variables on the performance of the motor is analyzed. A multi-objective optimization method based on genetic algorithm is introduced to maximize efficiency and power factor, as well as to minimize the end effect braking force, simultaneously. Finally, to validate the optimization results, 2D finite element method is employed.

  17. [Case report: Snake bite - an odd case].

    Science.gov (United States)

    Evers, Bettina; Muth, Claus-Martin; Georgieff, Michael; Dinse-Lambracht, Alexander

    2015-10-01

    Emergency medical service is called by a 54-year-old man bitten by his rattlesnake. Upon initial survey we find the patient in a cardiopulmonary stable condition. He has bite marks and pain on his rapidly swelling middle finger of his right hand. Our initial treatment is immobilization of the patient. The snake raiser has already called the poison control center in Munich. By the help of this institution we bring him to a hospital having the right antivenom on hand. © Georg Thieme Verlag Stuttgart · New York.

  18. Effects of High-Latitude Forcing Uncertainty on the Low-Latitude and Midlatitude Ionosphere

    Science.gov (United States)

    Pedatella, N. M.; Lu, G.; Richmond, A. D.

    2018-01-01

    Ensemble simulations are performed using the Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIE-GCM) in order to understand the role of high-latitude forcing uncertainty on the low-latitude and midlatitude ionosphere response to the April 2010 geomagnetic storm. The ensemble is generated by perturbing either the high-latitude electric potential or auroral energy flux in the assimilative mapping for ionosphere electrodynamics (AMIE). Simulations with perturbed high-latitude electric potential result in substantial intraensemble variability in the low-latitude and midlatitude ionosphere response to the geomagnetic storm, and the ensemble standard deviation for the change in NmF2 reaches 50-100% of the mean change. Such large intraensemble variability is not seen when perturbing the auroral energy flux. In this case, the effects of the forcing uncertainty are primarily confined to high latitudes. We therefore conclude that the specification of high-latitude electric fields is an important source of uncertainty when modeling the low-latitude and midlatitude ionosphere response to a geomagnetic storm. A multiple linear regression analysis of the results indicates that uncertainty in the storm time changes in the equatorial electric fields, neutral winds, and neutral composition can all contribute to the uncertainty in the ionosphere electron density. The results of the present study provide insight into the possible uncertainty in simulations of the low-latitude and midlatitude ionosphere response to geomagnetic storms due to imperfect knowledge of the high-latitude forcing.

  19. Bullous reactions to bed bug bites reflect cutaneous vasculitis

    Science.gov (United States)

    This study evaluates bullous cutaneous reactions and sequential histopathology in an individual sensitized to bed bug bites in an effort to better understand the allergic response and histology associated with these bites. There was a progression of the inflammatory response across time ranging from...

  20. Retrospective study of dog bite cases reported to ECWA Veterinary ...

    African Journals Online (AJOL)

    A retrospective study of dog bite cases reported to ECWA Veterinary Clinic Bukuru was carried out in Plateau State, Nigeria to understand the pattern of occurrence in this region. A total of two hundred and forty seven (247) dog bite cases were reported between May, 2009 and June, 2010. The dogs profile showed that ...

  1. Dog bite as a public health concern in Addis Ababa

    African Journals Online (AJOL)

    Bernt Lindtjørn

    Dog bite as a public health concern in Addis Ababa. Fasil Mengistu1, Kedir Hussen1, Abraham Ali1, Goroma Getahun1, Dessalegn Sifer1. Abstract. Introduction: Animal bites and scratches represent the most important public health issue related to dogs and cats because of the risk of rabies transmission associated with ...

  2. Human Bites of the Face with Tissue Losses in Cosmopolitan ...

    African Journals Online (AJOL)

    Dr. Milaki Asuku

    A retrospective series of thirty-six cases of human bites to the face with tissue losses requiring reconstruction ..... bite wounds when compared to other forms of trauma in our regional ... References. 1. Liston PN, Tong DC, Firth NA, Kieser JA.

  3. Factors Associated with Rabies Awareness and Attitude to Dog Bite ...

    African Journals Online (AJOL)

    Preponderance of stray dogs at the study site necessitated assessment of awareness on rabies and associated factors, attitude to dog bite and knowledge on rabies among students and staff members in a University community. We reviewed hospital records for dog bite cases from 2005 to 2010 and administered structured ...

  4. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... correct dose. For bites that itch , apply an ice pack or an over-the-counter anti-itch cream, such as hydrocortisone. Another option is to take an over-the-counter oral antihistamine. To reduce swelling , apply an ice pack to the bite. If you experience any ...

  5. Individual piglets' contribution to the development of tail biting

    NARCIS (Netherlands)

    Zonderland, J.J.; Kemp, B.; Bracke, M.B.M.; Hartog, den L.A.; Spoolder, H.A.M.

    2011-01-01

    Conflicting hypotheses exist about the contribution of individual pigs to the development of a tail-biting outbreak, but there is limited quantitative information to support or dismiss them. This study aims to quantify the development of tail-biting behaviour at pen and individual piglet level,

  6. Ward Round - Crocodile bites in Malawi: microbiology and surgical ...

    African Journals Online (AJOL)

    We present a case series of 5 patients admitted over 5 months to Queen Elizabeth Central Hospital who had sustained injuries from a crocodile bite. Three patients required amputation of a limb. The severe soft tissue injury associated with a crocodile bite and the unusual normal oral flora of the crocodile create challenges ...

  7. Management of common animal bites in the emergency centre

    African Journals Online (AJOL)

    Professor Engelbrecht's current fields of interest are bites, stings and poisonous plants. Correspondence to: ... Cross War Memorial Children's Hospital in. Cape Town ... infections. Wound infection with Pasteurella multocida usually occurs early (within 12 ..... Dog bite prevention: an assessment of child knowledge. J Pediatr ...

  8. Capnocytophaga canimorsus: an emerging cause of sepsis, meningitis, and post-splenectomy infection after dog bites.

    Science.gov (United States)

    Butler, T

    2015-07-01

    Newly named in 1989, Capnocytophaga canimorsus is a bacterial pathogen found in the saliva of healthy dogs and cats, and is transmitted to humans principally by dog bites. This review compiled all laboratory-confirmed cases, animal sources, and virulence attributes to describe its epidemiology, clinical features, and pathogenesis. An estimated 484 patients with a median age of 55 years were reported, two-thirds of which were male. The case-fatality rate was about 26%. Its clinical presentations included severe sepsis and fatal septic shock, gangrene of the digits or extremities, high-grade bacteremia, meningitis, endocarditis, and eye infections. Predispositions were prior splenectomy in 59 patients and alcoholism in 58 patients. Dog bites before illness occurred in 60%; additionally, in 27%, there were scratches, licking, or other contact with dogs or cats. Patients with meningitis showed more advanced ages, higher male preponderance, lower mortality, and longer incubation periods after dog bites than patients with sepsis (p spleens (p dog bites.

  9. Structure-activity relationship studies on the mosquito toxicity and biting deterrency of callicarpenal derivatives.

    Science.gov (United States)

    Cantrell, Charles L; Klun, Jerome A; Pridgeon, Julia; Becnel, James; Green, Solomon; Fronczek, Frank R

    2009-04-01

    Callicarpenal (=13,14,15,16-tetranorclerod-3-en-12-al=[(1S,2R,4aR,8aR)-1,2,3,4,4a,7,8,8a-octahydro-1,2,4a,5-tetramethylnaphthalen-1-yl]acetaldehyde; 1) has previously demonstrated significant mosquito bite-deterring activity against Aedes aegypti and Anopheles stephensi in addition to repellent activity against host-seeking nymphs of the blacklegged tick, Ixodes scapularis. In the present study, structural modifications were performed on callicarpenal (1) in an effort to understand the functional groups necessary for maintaining and/or increasing its activity and to possibly lead to more effective insect control agents. All modifications in this study targeted the C(12) aldehyde or the C(3) alkene functionalities or combinations thereof. Mosquito biting deterrency appeared to be influenced most by C(3) alkene modification as evidenced by catalytic hydrogenation that resulted in a compound having significantly less effectiveness than 1 at a test amount of 25 nmol/cm2. Oxidation and/or reduction of the C(12) aldehyde did not diminish mosquito biting deterrency, but, at the same time, none of the modifications were more effective than 1 in deterring mosquito biting. Toxicities of synthesized compounds towards Ae. aegypti ranged from an LD50 value of 2.36 to 40.11 microg per mosquito. Similarly, LD95 values ranged from a low of 5.59 to a high of 104.9 microg.

  10. Are bruxism and the bite causally related?

    Science.gov (United States)

    Lobbezoo, F; Ahlberg, J; Manfredini, D; Winocur, E

    2012-07-01

    In the dental profession, the belief that bruxism and dental (mal-)occlusion ('the bite') are causally related is widespread. The aim of this review was to critically assess the available literature on this topic. A PubMed search of the English-language literature, using the query 'Bruxism [Majr] AND (Dental Occlusion [Majr] OR Malocclusion [Majr])', yielded 93 articles, of which 46 papers were finally included in the present review*. Part of the included publications dealt with the possible associations between bruxism and aspects of occlusion, from which it was concluded that neither for occlusal interferences nor for factors related to the anatomy of the oro-facial skeleton, there is any evidence available that they are involved in the aetiology of bruxism. Instead, there is a growing awareness of other factors (viz. psychosocial and behavioural ones) being important in the aetiology of bruxism. Another part of the included papers assessed the possible mediating role of occlusion between bruxism and its purported consequences (e.g. tooth wear, loss of periodontal tissues, and temporomandibular pain and dysfunction). Even though most dentists agree that bruxism may have several adverse effects on the masticatory system, for none of these purported adverse effects, evidence for a mediating role of occlusion and articulation has been found to date. Hence, based on this review, it should be concluded that to date, there is no evidence whatsoever for a causal relationship between bruxism and the bite. © 2012 Blackwell Publishing Ltd.

  11. Percent voluntary inactivation and peak force predictions with the interpolated twitch technique in individuals with high ability of voluntary activation

    International Nuclear Information System (INIS)

    Herda, Trent J; Walter, Ashley A; Hoge, Katherine M; Stout, Jeffrey R; Costa, Pablo B; Ryan, Eric D; Cramer, Joel T

    2011-01-01

    The purpose of this study was to examine the sensitivity and peak force prediction capability of the interpolated twitch technique (ITT) performed during submaximal and maximal voluntary contractions (MVCs) in subjects with the ability to maximally activate their plantar flexors. Twelve subjects performed two MVCs and nine submaximal contractions with the ITT method to calculate percent voluntary inactivation (%VI). Additionally, two MVCs were performed without the ITT. Polynomial models (linear, quadratic and cubic) were applied to the 10–90% VI and 40–90% VI versus force relationships to predict force. Peak force from the ITT MVC was 6.7% less than peak force from the MVC without the ITT. Fifty-eight percent of the 10–90% VI versus force relationships were best fit with nonlinear models; however, all 40–90% VI versus force relationships were best fit with linear models. Regardless of the polynomial model or the contraction intensities used to predict force, all models underestimated the actual force from 22% to 28%. There was low sensitivity of the ITT method at high contraction intensities and the predicted force from polynomial models significantly underestimated the actual force. Caution is warranted when interpreting the % VI at high contraction intensities and predicted peak force from submaximal contractions

  12. Why your housecat's trite little bite could cause you quite a fright: a study of domestic felines on the occurrence and antibiotic susceptibility of Pasteurella multocida.

    Science.gov (United States)

    Freshwater, A

    2008-10-01

    Approximately four to five million animal bite wounds are reported in the USA each year. Domestic companion animals inflict the majority of these wounds. Although canine bites far outnumber feline bites, unlike the dog, the cat's bite is worse than its bark; 20-80% of all cat bites will become infected, compared with only 3-18% of dog bite wounds. Pasteurella multocida is the most commonly cultured bacterium from infected cat bite wounds. Anyone seeking medical attention for a cat-inflicted bite wound is given prophylactic/empiric penicillin or a derivative to prevent Pasteurella infection (provided they are not allergic to penicillins). In an effort to establish a carriage rate of P. multocida in the domestic feline, bacterial samples from the gingival margins of domestic northern Ohio cats (n=409) were cultured. Isolates were tested for antibiotic sensitivity as prophylactic/empiric use of penicillin and its derivatives could potentially give rise to antibiotic resistance in P. multocida. The high carriage rate (approximately 90%) of P. multocida observed was found to be independent of physiological and behavioural variables including age, breed, food type, gingival scale, lifestyle and sex. High antibiotic susceptibility percentages were observed for benzylpenicillin, amoxicillin-clavulanate, cefazolin, and azithromycin (100%, 100%, 98.37% and 94.02%, respectively) in P. multocida isolates. The high prevalence of P. multocida in the feline oral cavity indicates that prophylactic/empiric antibiotic therapy is still an appropriate response to cat bite wounds. Additionally, the susceptibility of P. multocida to penicillin and its derivatives indicates that they remain reliable choices for preventing and treating P. multocida infections.

  13. Haematophagous bat bites in Ecuadorian Amazon: characterisation and implications for sylvatic rabies prevention.

    Science.gov (United States)

    Romero-Sandoval, N; Parra, C; Gallegos, G; Guanopatín, A; Campaña, M F; Haro, M; Calapaqui, S; Moreta, C; Viteri, F; Feijoo-Cid, M; Martin, M

    2013-03-21

    To characterise the risk factors of haematophagous bat bites and to provide information to contribute to the prevention of rabies in Ecuador. Cross-sectional study based on interviews with 3518 individuals, from which two sets of variables were generated: characteristics of haematophagous bat attacks in the previous year among humans and risk factors for being bitten. Data were analysed using multivariate logistic regression models, taking history of bat bites in the previous year as the response variable. In the previous year 723 (20.6%, 95%CI 19.3-21.9) of the participants declared having received haematophagous bat bites and 50.4% in the previous month, giving an incidence rate of 10.4% (95%CI 9.6-11.6) per month. Sleeping on the floor or in a hammock (adjusted odds ratio [aOR] 1.58, 95%CI 1.21-2.06), not using a protective bed net (aOR 1.25, 95%CI 1.03-1.50) and living in a dwelling with permanent openings in the structure (aOR 1.49, 95%CI 1.12-1.95) were associated with a higher probability of bat bites. Those most affected were the group aged ≤12 years (age 13-19 years, aOR 0.39, 95%CI 0.32-0.48; age ≥20 years, aOR 0.67, 95%CI 0.50-0.90). Primary prevention based on pre-exposure vaccination would be justifiable given the high dispersion of the population and the high incidence of bat bites. As a secondary protective measure, communities should work towards increasing the use of protective measures and putting barriers in permanent openings in their dwellings.

  14. Dynamic force microscopy with quartz tuning forks at high oscillation amplitudes

    International Nuclear Information System (INIS)

    Labardi, M

    2007-01-01

    Dynamic force microscopy (DFM) with the self-oscillator (SO) method allows reasonably high scanning rates even with high Q-factors of the resonant force sensor, typical of cantilevers in ultra-high vacuum and of quartz tuning forks. However, due to simpler interpretation of force spectroscopy measurements, small oscillation amplitudes (sub-nm level) are generally preferred. In applications like 'apertureless' scanning near-field optical microscopy (SNOM), oscillation amplitudes of the order of 5-10 nm are needed to increase optical sensitivity and to apply standard optical artefact suppression methods. This motivates the study of the behaviour of tuning forks driven at such high amplitudes, as compared to usual air-operated cantilevers. Both constant-excitation-amplitude (CE) and constant-oscillation-amplitude (CA) modes of SO-DFM are analysed, since the CA mode is more convenient for SNOM applications, denoting remarkable differences. In particular, possible instability effects, previously found in CE mode, are not anticipated for CA mode. It is shown how resonance and approach ('isophase') curves in both modes can be conveniently described in terms of the usual 'normalized frequency shift' γ and of a 'normalized gain' η, defined as a measurement of surface dissipation

  15. HIGHLY QUALIFIED WORKING FORCE – KEY ELEMENT OF INNOVATIVE DEVELOPMENT MODEL

    Directory of Open Access Journals (Sweden)

    M. Avksientiev

    2014-12-01

    Full Text Available Highly qualified working force is a central element of intensive development model in modern society. The article surveys the experience of countries that managed to transform their economy to the innovative one. Ukrainian economy cannot stand aside processes that dominate the world economy trends, thus we are to use this experience to succeed in future. Today any government of the world is facing challenges that occur due to transformation of the economy into informational one. This type of economy causes its transformation form extensive to intensive one. The main reasons under that is limitation of nature resources, material factors of production. Thus this approach depends much on the quality of working force. Unfortunately in Ukraine there is a misbalance in specialist preparation. This puts additional pressure on the educational sphere also. In order to avoid this pressure we are to conduct reforms in education sphere. Nowadays, in the world views and concepts of governmental role in the social development are changing. This why, even at times of economic recession educational costs are not reduced under the new economical doctrine in the EU. Highly qualified specialists, while creating new products and services play role of engineers in XXI century. They are to lead their industries to world leading positions. From economic point of view, highly qualified specialists benefit society with higher income rates, taxation and thus, increasing the living standards in society. Thus, the majority if modern scientists prove the importance of highly trained working force for more effective economic development.

  16. High-force NdFeB-based magnetic tweezers device optimized for microrheology experiments.

    Science.gov (United States)

    Lin, Jun; Valentine, Megan T

    2012-05-01

    We present the design, calibration, and testing of a magnetic tweezers device that employs two pairs of permanent neodymium iron boron magnets surrounded by low-carbon steel focusing tips to apply large forces to soft materials for microrheology experiments. Our design enables the application of forces in the range of 1-1800 pN to ∼4.5 μm paramagnetic beads using magnet-bead separations in the range of 0.3-20 mm. This allows the use of standard coverslips and sample geometries. A high speed camera, custom LED-based illumination scheme, and mechanically stabilized measurement platform are employed to enable the measurement of materials with viscoelastic moduli as high as ∼1 kPa.

  17. High-force NdFeB-based magnetic tweezers device optimized for microrheology experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jun [Department of Mechanical Engineering, University of California, Santa Barbara, California 93106 (United States); Biomolecular Science and Engineering Program, University of California, Santa Barbara, California 93106 (United States); Valentine, Megan T. [Department of Mechanical Engineering, University of California, Santa Barbara, California 93106 (United States)

    2012-05-15

    We present the design, calibration, and testing of a magnetic tweezers device that employs two pairs of permanent neodymium iron boron magnets surrounded by low-carbon steel focusing tips to apply large forces to soft materials for microrheology experiments. Our design enables the application of forces in the range of 1-1800 pN to {approx}4.5 {mu}m paramagnetic beads using magnet-bead separations in the range of 0.3-20 mm. This allows the use of standard coverslips and sample geometries. A high speed camera, custom LED-based illumination scheme, and mechanically stabilized measurement platform are employed to enable the measurement of materials with viscoelastic moduli as high as {approx}1 kPa.

  18. Three-dimensional Force and Kinematic Interactions in V1 Skating at High Speeds.

    Science.gov (United States)

    Stöggl, Thomas; Holmberg, Hans-Christer

    2015-06-01

    To describe the detailed kinetics and kinematics associated with use of the V1 skating technique at high skiing speeds and to identify factors that predict performance. Fifteen elite male cross-country skiers performed an incremental roller-skiing speed test (Vpeak) on a treadmill using the V1 skating technique. Pole and plantar forces and whole-body kinematics were monitored at four submaximal speeds. The propulsive force of the "strong side" pole was greater than that of the "weak side" (P skating at high speeds. The faster skiers exhibit more symmetric leg motion on the "strong" and "weak" sides, as well as more synchronized poling. With respect to methods, the pressure insoles and three-dimensional kinematics in combination with the leg push-off model described here can easily be applied to all skating techniques, aiding in the evaluation of skiing techniques and comparison of effectiveness.

  19. Tubular bending and pull-out forces in high-curvature well bores

    International Nuclear Information System (INIS)

    Dareing, D.W.; Ahlers, C.A.

    1991-01-01

    This paper is concerned with drag forces developed on tubulars in high-curvature well bores typically found in drainhole and horizontal drilling. The dog-leg severity of these types of boreholes are considerably higher than those typically found in conventional directional drilling. The objective of the study was to determine the significance of bending stiffness on drag forces in the pull-out mode. The method of analysis treats the tubular as a multi-spanned curved beam under tension and solves for radial displacements, slope, shear and bending moment over each span. Calculations show that bending stiffness is a minor factor provided there are no locally severe dog legs superimposed in the high-curvature well bore

  20. Laser apparatus for surgery and force therapy based on high-power semiconductor and fibre lasers

    International Nuclear Information System (INIS)

    Minaev, V P

    2005-01-01

    High-power semiconductor lasers and diode-pumped lasers are considered whose development qualitatively improved the characteristics of laser apparatus for surgery and force therapy, extended the scope of their applications in clinical practice, and enhanced the efficiency of medical treatment based on the use of these lasers. The characteristics of domestic apparatus are presented and their properties related to the laser emission wavelength used in them are discussed. Examples of modern medical technologies based on these lasers are considered. (invited paper)

  1. Magnetic field and force analysis of high Tc superconductor with flux flow and creep

    International Nuclear Information System (INIS)

    Yoshida, Yoshikatsu; Uesaka, Mitsuru; Miya, Kenzo

    1994-01-01

    This paper describes a new method for the magnetic force analysis of high T c superconductor based on the flux flow and creep model. The introduction of the artificial conductivity, which is used in the conventional method, is not needed. The CPU time requirement of the calculations is considerably lower than that in the case of the conventional method. Thereby the vibration of a levitated permanent magnet was numerically analyzed by taking into account the flux flow and creep

  2. Search and Rescue in the High North: An Air Force Mission?

    Science.gov (United States)

    2013-12-01

    at the strange new things in the land of the midnight sun. What wouldn’t surprise him are the things that never change: six months of darkness ...8-98) Prescribed by ANSI Std Z39-18 November–December 2013 Air & Space Power Journal | 5 Conway Search and Rescue in the High North Feature tourism ...official sanction of the Department of Defense, Air Force, Air Education and Training Command, Air University, or other agencies or departments of

  3. Burnout in boiling heat transfer. Part III. High-quality forced-convection systems

    International Nuclear Information System (INIS)

    Bergles, A.E.

    1979-01-01

    This is the final part of a review of burnout during boiling heat transfer. The status of burnout in high-quality forced-convection systems is reviewed, and recent developments are summarized in detail. A general guide to the considerable literature is given. Parametric effects and correlations for water in circular and noncircular ducts are presented. Other topics discussed include transients, steam-generator applications, correlations for other fluids, fouling, and augmentation

  4. High-throughput single-molecule force spectroscopy for membrane proteins

    Science.gov (United States)

    Bosshart, Patrick D.; Casagrande, Fabio; Frederix, Patrick L. T. M.; Ratera, Merce; Bippes, Christian A.; Müller, Daniel J.; Palacin, Manuel; Engel, Andreas; Fotiadis, Dimitrios

    2008-09-01

    Atomic force microscopy-based single-molecule force spectroscopy (SMFS) is a powerful tool for studying the mechanical properties, intermolecular and intramolecular interactions, unfolding pathways, and energy landscapes of membrane proteins. One limiting factor for the large-scale applicability of SMFS on membrane proteins is its low efficiency in data acquisition. We have developed a semi-automated high-throughput SMFS (HT-SMFS) procedure for efficient data acquisition. In addition, we present a coarse filter to efficiently extract protein unfolding events from large data sets. The HT-SMFS procedure and the coarse filter were validated using the proton pump bacteriorhodopsin (BR) from Halobacterium salinarum and the L-arginine/agmatine antiporter AdiC from the bacterium Escherichia coli. To screen for molecular interactions between AdiC and its substrates, we recorded data sets in the absence and in the presence of L-arginine, D-arginine, and agmatine. Altogether ~400 000 force-distance curves were recorded. Application of coarse filtering to this wealth of data yielded six data sets with ~200 (AdiC) and ~400 (BR) force-distance spectra in each. Importantly, the raw data for most of these data sets were acquired in one to two days, opening new perspectives for HT-SMFS applications.

  5. High-throughput single-molecule force spectroscopy for membrane proteins

    International Nuclear Information System (INIS)

    Bosshart, Patrick D; Casagrande, Fabio; Frederix, Patrick L T M; Engel, Andreas; Fotiadis, Dimitrios; Ratera, Merce; Palacin, Manuel; Bippes, Christian A; Mueller, Daniel J

    2008-01-01

    Atomic force microscopy-based single-molecule force spectroscopy (SMFS) is a powerful tool for studying the mechanical properties, intermolecular and intramolecular interactions, unfolding pathways, and energy landscapes of membrane proteins. One limiting factor for the large-scale applicability of SMFS on membrane proteins is its low efficiency in data acquisition. We have developed a semi-automated high-throughput SMFS (HT-SMFS) procedure for efficient data acquisition. In addition, we present a coarse filter to efficiently extract protein unfolding events from large data sets. The HT-SMFS procedure and the coarse filter were validated using the proton pump bacteriorhodopsin (BR) from Halobacterium salinarum and the L-arginine/agmatine antiporter AdiC from the bacterium Escherichia coli. To screen for molecular interactions between AdiC and its substrates, we recorded data sets in the absence and in the presence of L-arginine, D-arginine, and agmatine. Altogether ∼400 000 force-distance curves were recorded. Application of coarse filtering to this wealth of data yielded six data sets with ∼200 (AdiC) and ∼400 (BR) force-distance spectra in each. Importantly, the raw data for most of these data sets were acquired in one to two days, opening new perspectives for HT-SMFS applications

  6. High-throughput single-molecule force spectroscopy for membrane proteins

    Energy Technology Data Exchange (ETDEWEB)

    Bosshart, Patrick D; Casagrande, Fabio; Frederix, Patrick L T M; Engel, Andreas; Fotiadis, Dimitrios [M E Mueller Institute for Structural Biology, Biozentrum of the University of Basel, CH-4056 Basel (Switzerland); Ratera, Merce; Palacin, Manuel [Institute for Research in Biomedicine, Barcelona Science Park, Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona and Centro de Investigacion Biomedica en Red de Enfermedades Raras, E-08028 Barcelona (Spain); Bippes, Christian A; Mueller, Daniel J [BioTechnology Center, Technical University, Tatzberg 47, D-01307 Dresden (Germany)], E-mail: andreas.engel@unibas.ch, E-mail: dimitrios.fotiadis@mci.unibe.ch

    2008-09-24

    Atomic force microscopy-based single-molecule force spectroscopy (SMFS) is a powerful tool for studying the mechanical properties, intermolecular and intramolecular interactions, unfolding pathways, and energy landscapes of membrane proteins. One limiting factor for the large-scale applicability of SMFS on membrane proteins is its low efficiency in data acquisition. We have developed a semi-automated high-throughput SMFS (HT-SMFS) procedure for efficient data acquisition. In addition, we present a coarse filter to efficiently extract protein unfolding events from large data sets. The HT-SMFS procedure and the coarse filter were validated using the proton pump bacteriorhodopsin (BR) from Halobacterium salinarum and the L-arginine/agmatine antiporter AdiC from the bacterium Escherichia coli. To screen for molecular interactions between AdiC and its substrates, we recorded data sets in the absence and in the presence of L-arginine, D-arginine, and agmatine. Altogether {approx}400 000 force-distance curves were recorded. Application of coarse filtering to this wealth of data yielded six data sets with {approx}200 (AdiC) and {approx}400 (BR) force-distance spectra in each. Importantly, the raw data for most of these data sets were acquired in one to two days, opening new perspectives for HT-SMFS applications.

  7. Study of Cutting Edge Temperature and Cutting Force of End Mill Tool in High Speed Machining

    Directory of Open Access Journals (Sweden)

    Kiprawi Mohammad Ashaari

    2017-01-01

    Full Text Available A wear of cutting tools during machining process is unavoidable due to the presence of frictional forces during removing process of unwanted material of workpiece. It is unavoidable but can be controlled at slower rate if the cutting speed is fixed at certain point in order to achieve optimum cutting conditions. The wear of cutting tools is closely related with the thermal deformations that occurred between the frictional contact point of cutting edge of cutting tool and workpiece. This research paper is focused on determinations of relationship among cutting temperature, cutting speed, cutting forces and radial depth of cutting parameters. The cutting temperature is determined by using the Indium Arsenide (InAs and Indium Antimonide (InSb photocells to measure infrared radiation that are emitted from cutting tools and cutting forces is determined by using dynamometer. The high speed machining process is done by end milling the outer surface of carbon steel. The signal from the photocell is digitally visualized in the digital oscilloscope. Based on the results, the cutting temperature increased as the radial depth and cutting speed increased. The cutting forces increased when radial depth increased but decreased when cutting speed is increased. The setup for calibration and discussion of the experiment will be explained in this paper.

  8. The response of a high-speed train wheel to a harmonic wheel-rail force

    International Nuclear Information System (INIS)

    Sheng, Xiaozhen; Liu, Yuxia; Zhou, Xin

    2016-01-01

    The maximum speed of China's high-speed trains currently is 300km/h and expected to increase to 350-400km/h. As a wheel travels along the rail at such a high speed, it is subject to a force rotating at the same speed along its periphery. This fast moving force contains not only the axle load component, but also many components of high frequencies generated from wheel-rail interactions. Rotation of the wheel also introduces centrifugal and gyroscopic effects. How the wheel responds is fundamental to many issues, including wheel-rail contact, traction, wear and noise. In this paper, by making use of its axial symmetry, a special finite element scheme is developed for responses of a train wheel subject to a vertical and harmonic wheel-rail force. This FE scheme only requires a 2D mesh over a cross-section containing the wheel axis but includes all the effects induced by wheel rotation. Nodal displacements, as a periodic function of the cross-section angle 6, can be decomposed, using Fourier series, into a number of components at different circumferential orders. The derived FE equation is solved for each circumferential order. The sum of responses at all circumferential orders gives the actual response of the wheel. (paper)

  9. Epidemiological study of animal bites and rabies in Lorestan Province in West of Iran during 2004-2014 for preventive purposes

    Directory of Open Access Journals (Sweden)

    Ali Chegeni Sharafi

    2016-01-01

    Full Text Available Background: Despite the progress made, animal bites and rabies are one of the important health problems in the country. The purpose of this study was to investigate the epidemiology of animal bites and rabies during 2004-2014 in Lorestan Province to prevent them in population of the province for the future prospective aspects. Materials and Methods: In a descriptive cross-sectional study, all those cases bitten in the province, during 2004 and 2014, were studied. The required information about the age, sex, the bitten organ, type of the invasive animal time, and location of the event were collected in questionnaires and then analyzed. Results: The total number of cases of animal rabies during the period of study was 43,892, shown at the rate of 223.23 in 100,000 people. Seventy-eight percent of animal bites in rural areas, 41.42% in the ages 10-29-year-old, 26.8% of cases were students, 56.77% leg bites, and 82.5% of dog bites. Four cases of human rabies were observed during this period. Conclusions: Rate of animal bites and rabies is high in Lorestan Province. Controlling animals such as dogs and cats in the province through training people at risk, especially among the students, rural areas and inter-sectorial coordination to eliminate stray animals should be considered over and over. Preventive actions to avoid bites are a priority.

  10. Treatment of hyperdivergent growth pattern and anterior open bite with posterior metallic bite planes.

    Science.gov (United States)

    Ciavarella, Domenico; Lo Russo, Lucio; Nichelini, Jeffrey; Mastrovincenzo, Mario; Barbato, Ersilia; Laurenziello, Michele; Montaruli, Graziano; Lo Muzio, Lorenzo

    2017-12-01

    In the present paper, the authors analyze the effect of the "Swallowing Occlusal Contact Intercept Appliance" (SOCIA) in treatment of children with hyperdivergent Class II malocclusion. This functional appliance has no intra-oral anchorage, but induces a continuous periodontal, muscular, and articular stimulation. Twenty-six patients with hyperdivergent growth and class II malocclusion were selected and treated with SOCIA appliance. Cephalometric analysis was performed before treatment (T1) and immediately after the treatment (T2). After 24 months treatment authors observed a modification of maxillary growth with a reduction of the divergence with an increase of the posterior facial height, a modification of condylar inclination and forward position of the a hyoid. No modifications was observed about the ANB angle. After treatment the open bite was resolved with a reduction of the inclination of the upper incisors. SOCIA is a reliable functional appliance in growing age patients with a hyperdivergent pattern growth, anterior open bite and class II molar malocclusion.

  11. Magnetic Signals of High-Temperature Superconductor Bulk During the Levitation Force Measurement Process

    Science.gov (United States)

    Huang, Huan; Zheng, Jun; Qian, Nan; Che, Tong; Zheng, Botian; Jin, Liwei; Deng, Zigang

    2017-05-01

    In order to study the commonly neglected magnetic field information in the course of levitation force measurement process in a superconducting maglev system, a multipoint magnetic field measurement platform was employed to acquire magnetic signals of a bulk high-Tc superconductor on both the top and the bottom surface. Working conditions including field cooling (FC) and zero field cooling were investigated for these vertical down and up motions above a permanent magnet guideway performed on a HTS maglev measurement system. We have discussed the magnetic flux variation process based on the Bean model. A magnetic hysteresis effect similar to the levitation force hysteresis loop of the bulk superconductor was displayed and analyzed in this paper. What is more valuable, there exists some available magnetic flux on the top surface of the bulk superconductor, and the proportion is as high as 62.42% in the FC condition, which provides an experimental hint to design the superconductor bulk and the applied field for practical use in a more efficient way. In particular, this work reveals real-time magnetic flux variation of the bulk superconductor in the levitation application, which is the other important information in contrast to the macroscopic levitation and guidance force investigations in previous studies, and it enriches the existing research methods. The results are significant for understanding the magnetic characteristic of superconductors, and they can contribute to optimize the present HTS maglev system design.

  12. Analysis of Electromagnetics Forces on Magnetically Suspended High-Speed Trains

    Directory of Open Access Journals (Sweden)

    Daniel Mayer

    2004-01-01

    Full Text Available High-speed superexpresses (HSST developed by Japanese airlines (JAL are based on the electrodynamics principle of magnetic suspension. The track contains short-circuited coils and interaction between them and superconductive coils in the vehicle produces its suspension. The paper includes a mathematical model for traction electrodynamics suspension device HSST represented by a system of linear differential equations with coefficients varying in time. Numerical analysis of this model fields the velocity-dependent lift and drag forces acting on the system. The time distribution of the lift force exhibits certain oscillations that may be suppressed by suitable placement of several superconductive levitation wings in the vehicle. The results obtained are in a good agreement with the knowledge found by various authors on prototype vehicles.

  13. Mechanically stable tuning fork sensor with high quality factor for the atomic force microscope.

    Science.gov (United States)

    Kim, Kwangyoon; Park, Jun-Young; Kim, K B; Lee, Naesung; Seo, Yongho

    2014-01-01

    A quartz tuning fork was used instead of cantilever as a force sensor for the atomic force microscope. A tungsten tip was made by electrochemical etching from a wire of 50 µm diameter. In order to have mechanical stability of the tuning fork, it was attached on an alumina plate. The tungsten tip was attached on the inside end of a prong of a tuning fork. The phase shift was used as a feedback signal to control the distance between the tip and sample, and the amplitude was kept constant using a lock-in amplifier and a homemade automatic gain controller. Due to the mechanical stability, the sensor shows a high quality factor (∼10(3)), and the image quality obtained with this sensor was equivalent to that of the cantilever-based AFM. © 2014 Wiley Periodicals, Inc.

  14. Safety aspects of forced flow cooldown transients in modular high temperature gas-cooled reactors

    International Nuclear Information System (INIS)

    Kroeger, P.G.

    1992-01-01

    During some of the design basis accidents in Modular High Temperature Gas Cooled Reactors (MHTGRs) the main Heat Transport System (HTS) and the Shutdown Cooling System (SCS), are assumed to have failed. Decay heat is then removed by the passive Reactor Cavity Cooling System (RCCS) only. If either forced flow cooling system becomes available during such a transient, its restart could significantly reduce the down-time. This paper uses the THATCH code to examine whether such restart, during a period of elevated core temperatures, can be accomplished within safe limits for fuel and metal component temperatures. If the reactor is scrammed, either system can apparently be restarted at any time, without exceeding any safe limits. However, under unscrammed conditions a restart of forced cooling can lead to recriticality, with fuel and metal temperatures significantly exceeding the safety limits

  15. High frequency write head measurement with the phase detection magnetic force microscope

    International Nuclear Information System (INIS)

    Abe, M.; Tanaka, Y.

    2001-01-01

    We demonstrated the measurement of the high frequency (HF) magnetic field of a write head with the phase detection magnetic force microscope. An amplitude-modulated current was applied to the head coil to detect the force gradient induced by the HF magnetic field. Spatial resolution of this method was higher than that of the deflection detection method previously proposed. By the phase detection method, dynamic HF magnetic fields at the poles of the write heads were clearly imaged. HF magnetic field leakage was observed along the P2 pole shape on the air-bearing surface. The frequency dependence of the write head dynamics up to 350 MHz was also investigated. [copyright] 2001 American Institute of Physics

  16. Skeletal muscle collagen content in humans after high-force eccentric contractions

    DEFF Research Database (Denmark)

    Mackey, Abigail; Donnelly, Alan E; Turpeenniemi-Hujanen, Taina

    2004-01-01

    The purpose of this study was to investigate the effects of high-force eccentric muscle contractions on collagen remodeling and on circulating levels of matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) in humans. Nine volunteers [5 men and 4 women, mean age 23 (SD...... 4) yr] each performed a bout of 100 maximum voluntary eccentric contractions of the knee extensors. Muscle biopsies were taken before exercise and on days 4 and 22 afterward. Image analysis of stained tissue sections was used to quantify endomysial collagen staining intensity. Maximum voluntary...... contractile force declined by 39 +/- 23% (mean +/- SD) on day 2 postexercise and recovered thereafter. Serum creatine kinase activity peaked on day 4 postexercise (P Collagen type IV staining intensity increased significantly on day 22 postexercise to 126 +/- 29% (mean +/- SD) of preexercise values...

  17. Possible manifestation of long range forces in high energy hadron collisions

    International Nuclear Information System (INIS)

    Kuraev, Eh.A.; Ferro, P.; Trentadue, L.

    1997-01-01

    Pion-pion and photon-photon scattering are discussed.. We obtain, starting from the impact representation introduced by Cheng and Wu a new contribution to the high energy hadron-hadron scattering amplitude for small transferred momentum q 2 of the form is (q 2 /m 4 )ln(-q 2 /m 2 ). This behaviour may be interpreted as a manifestation of long transverse-range forces between hadrons which, for ρ>> m -1 fall off as ρ -4 . We consider the examples of pion and photon scattering with photons converted in the intermediate state to two pairs of quarks interacting by exchanging two gluon colorless state. A phenomenological approach for proton impact factor is used to analyze proton-proton scattering. The analysis of the lowest order radiative corrections for the case of photon-photon scattering is done. We discuss the possibility of observing the effects of these long range forces

  18. Tip radius preservation for high resolution imaging in amplitude modulation atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Jorge R., E-mail: jorge.rr@cea.cu [Instituto de Ciencia de Materiales de Madrid, Sor Juana Inés de la Cruz 3, Canto Blanco, 28049 Madrid, España (Spain)

    2014-07-28

    The acquisition of high resolution images in atomic force microscopy (AFM) is correlated to the cantilever's tip shape, size, and imaging conditions. In this work, relative tip wear is quantified based on the evolution of a direct experimental observable in amplitude modulation atomic force microscopy, i.e., the critical amplitude. We further show that the scanning parameters required to guarantee a maximum compressive stress that is lower than the yield/fracture stress of the tip can be estimated via experimental observables. In both counts, the optimized parameters to acquire AFM images while preserving the tip are discussed. The results are validated experimentally by employing IgG antibodies as a model system.

  19. Human behavior preceding dog bites to the face.

    Science.gov (United States)

    Rezac, P; Rezac, K; Slama, P

    2015-12-01

    Facial injuries caused by dog bites pose a serious problem. The aims of this study were to determine human behavior immediately preceding a dog bite to the face and to assess the effects of victim age and gender and dog sex and size on the location of the bite to the face and the need for medical treatment. Complete data on 132 incidents of bites to the face were analysed. A human bending over a dog, putting the face close to the dog's face, and gazing between victim and dog closely preceded a dog bite to the face in 76%, 19% and 5% of cases, respectively. More than half of the bites were directed towards the central area of the victim's face (nose, lips). More than two thirds of the victims were children, none of the victims was an adult dog owner and only adult dogs bit the face. Victim's age and gender and dog's sex and size did not affect the location of the bite on the face. People who were bitten by large dogs sought medical treatment more often than people who were bitten by small dogs (P face close to the dog's face and gazing between human and dog should be avoided, and children should be carefully and constantly supervised when in the presence of dogs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Texas coral snake (Micrurus tener) bites.

    Science.gov (United States)

    Morgan, David L; Borys, Douglas J; Stanford, Rhandi; Kjar, Dean; Tobleman, William

    2007-02-01

    The clinical features of bites from Texas coral snakes (Micrurus tener) have not been well studied. Our goal was to review the largest number of victims of Texas coral snakebites to determine their characteristics, effects, treatment, and outcome. Retrospective case series of Micrurus tener exposures reported to the Texas Poison Center Network from 2000 to 2004. Eighty-two patients were included in the analysis. Most (57.3%) were 18 to 49-year-old men. Almost 90% had local swelling, pain, erythema, or paresthesias. Only 7.3% had systemic effects, and none of these were severe. Over half received coral snake antivenin, and 15.9% were given opioids for pain. No patient died and no patient required mechanical ventilation due to hypoventilation from the snakebite. There were more local findings and less severe systemic effects than previously reported. Antivenin is not needed for most of these patients, and opioids may be administered safely.

  1. Primary lymph node responses to mosquito bites.

    Science.gov (United States)

    Mellink, J J; Vos, B J

    1977-03-29

    Post-auricular lymph node responses and changes in fresh weight of thymus and spleen of hamsters and mice at 4 and 8 days after primary exposure of both ears to 20 bites by the mosquito Aedes aegypti were studied quantitatively. In both hosts lymph node changes characteristic of the development of cell-mediated immune responses and those which are believed to lead to antibody production occurred, with the emphasis on the latter phenomena. No reactions of thymus and spleen were observed. The responses recorded are considered to be immunologically specific. In hamsters, but not in mice, the responses related to humoral sensitization coincided in time to a large extent with those of the cell-mediated immune processes. The stronger humoral responses in mice were probably in the first place the result of the relatively higher dosages applied.

  2. Development of nanomanipulator using a high-speed atomic force microscope coupled with a haptic device

    International Nuclear Information System (INIS)

    Iwata, F.; Ohashi, Y.; Ishisaki, I.; Picco, L.M.; Ushiki, T.

    2013-01-01

    The atomic force microscope (AFM) has been widely used for surface fabrication and manipulation. However, nanomanipulation using a conventional AFM is inefficient because of the sequential nature of the scan-manipulation scan cycle, which makes it difficult for the operator to observe the region of interest and perform the manipulation simultaneously. In this paper, a nanomanipulation technique using a high-speed atomic force microscope (HS-AFM) is described. During manipulation using the AFM probe, the operation is periodically interrupted for a fraction of a second for high-speed imaging that allows the topographical image of the manipulated surface to be periodically updated. With the use of high-speed imaging, the interrupting time for imaging can be greatly reduced, and as a result, the operator almost does not notice the blink time of the interruption for imaging during the manipulation. This creates a more intuitive interface with greater feedback and finesse to the operator. Nanofabrication under real-time monitoring was performed to demonstrate the utility of this arrangement for real-time nanomanipulation of sample surfaces under ambient conditions. Furthermore, the HS-AFM is coupled with a haptic device for the human interface, enabling the operator to move the HS-AFM probe to any position on the surface while feeling the response from the surface during the manipulation. - Highlights: • A nanomanipulater based on a high-speed atomic force microscope was developped. • High-speed imaging provides a valuable feedback during the manipulation operation. • Operator can feel the response from the surface via a haptic device during manipulation. • Nanofabrications under real-time monitoring were successfully performed

  3. A qualitative investigation of the perceptions of female dog-bite victims and implications for the prevention of dog bites.

    Science.gov (United States)

    Westgarth, Carri; Watkins, Francine

    2015-01-01

    Preventing dog bites is an increasingly important public health and political issue with implications for both human and animal health and welfare. Expert opinion is that most bites are preventable. Intervention materials have been designed to educate people on how to assess the body language of dogs, evaluate risk, and take appropriate action. The effectiveness of this approach is rarely evaluated and the incidence of dog bites is thought to be increasing. Is the traditional approach to dog bite prevention working as well as it should? In this novel, small scale qualitative study, the perceptions of victims regarding their dog bite experience were explored in-depth. The study recruited 8 female participants who had been bitten by a dog in the past 5 years. In-depth, one-to-one interviews were conducted, transcribed, and analyzed using thematic analysis. The findings indicate that dog bites may not be as easily preventable as previously presumed, and that education about dog body language may not prevent some types of dog bites. The reasons participants were bitten were multifaceted and complex. In some cases, there was no interaction with the dog before the bite so there was no opportunity to assess the situation and modify behavior around the dog accordingly. Identifying who was to blame, and had responsibility for preventing the bite, was straightforward for the participants in hindsight. Those bitten blamed themselves and/or the dog owner, but not the dog. Most participants already felt they had a theoretical knowledge that would allow them to recognize dog aggression before the dog bite, yet participants, especially those who worked regularly with dogs, routinely believed, "it would not happen to me." We also identified an attitude that bites were "just one of those things," which could also be a barrier prevention initiatives. Rather than being special to the human-canine relationship, the attitudes discovered mirror those found in other areas of injury

  4. High-Force Versus Low-Force Lumbar Traction in Acute Lumbar Sciatica Due to Disc Herniation: A Preliminary Randomized Trial.

    Science.gov (United States)

    Isner-Horobeti, Marie-Eve; Dufour, Stéphane Pascal; Schaeffer, Michael; Sauleau, Erik; Vautravers, Philippe; Lecocq, Jehan; Dupeyron, Arnaud

    This study compared the effects of high-force versus low-force lumbar traction in the treatment of acute lumbar sciatica secondary to disc herniation. A randomized double blind trial was performed, and 17 subjects with acute lumbar sciatica secondary to disc herniation were assigned to high-force traction at 50% body weight (BW; LT50, n = 8) or low force traction at 10% BW (LT10, n = 9) for 10 sessions in 2 weeks. Radicular pain (visual analogue scale [VAS]), lumbo-pelvic-hip complex motion (finger-to-toe test), lumbar-spine mobility (Schöber-Macrae test), nerve root compression (straight-leg-raising test), disability (EIFEL score), drug consumption, and overall evaluation of each patient were measured at days 0, 7, 1, 4, and 28. Significant (P sciatica secondary to disc herniation who received 2 weeks of lumbar traction reported reduced radicular pain and functional impairment and improved well-being regardless of the traction force group to which they were assigned. The effects of the traction treatment were independent of the initial level of medication and appeared to be maintained at the 2-week follow-up. Copyright © 2016. Published by Elsevier Inc.

  5. An Analytical Study of Mammalian Bite Wounds Requiring Inpatient Management

    Directory of Open Access Journals (Sweden)

    Young-Geun Lee

    2013-11-01

    Full Text Available BackgroundMammalian bite injuries create a public health problem because of their frequency, potential severity, and increasing number. Some researchers have performed fragmentary analyses of bite wounds caused by certain mammalian species. However, little practical information is available concerning serious mammalian bite wounds that require hospitalization and intensive wound management. Therefore, the purpose of this study was to perform a general review of serious mammalian bite wounds.MethodsWe performed a retrospective review of the medical charts of 68 patients who were referred to our plastic surgery department for the treatment of bite wounds between January 2003 and October 2012. The cases were analyzed according to the species, patient demographics, environmental factors, injury characteristics, and clinical course.ResultsAmong the 68 cases of mammalian bite injury, 58 (85% were caused by dogs, 8 by humans, and 2 by cats. Most of those bitten by a human and both of those bitten by cats were male. Only one-third of all the patients were children or adolescents. The most frequent site of injury was the face, with 40 cases, followed by the hand, with 16 cases. Of the 68 patients, 7 were treated with secondary intention healing. Sixty-one patients underwent delayed procedures, including delayed direct closure, skin graft, composite graft, and local flap.ConclusionsBased on overall findings from our review of the 68 cases of mammalian bites, we suggest practical guidelines for the management of mammalian bite injuries, which could be useful in the treatment of serious mammalian bite wounds.

  6. Customized lingual bracket system and skeletal anchorage system for open bite correction

    Directory of Open Access Journals (Sweden)

    Toru Inami

    2016-01-01

    Full Text Available We treated a female patient with open bite and high-angle Class II Division 2 malocclusion using fully customized lingual appliances, orthodontic anchor screws (OAS, and a skeletal anchorage system (SAS. By carefully controlling torque, anchorage, and vertical skeletal and dental factors, we were able to obtain proper anterior coupling. Even after the retention phase of treatment, the occlusion was maintained, indicating that we provided proper treatment according to the properly designed treatment plan. This also indicates that cases with an extremely high level of difficulty, as in the present case with high-angle retrognathic mandible and open bite, can be treated by combining the Incognito appliance (a fully customized lingual bracket appliance with a SAS and OAS.

  7. A new atomic force microscopy based technique for studying nanoscale friction at high sliding velocities

    International Nuclear Information System (INIS)

    Tambe, Nikhil S; Bhushan, Bharat

    2005-01-01

    Tribological studies on the micro/nanoscale conducted using an atomic force microscope (AFM) have been limited to low sliding velocities ( -1 ) due to inherent instrument limitations. Studies of tribological properties of materials, coatings and lubricants that find applications in micro/nanoelectromechanical systems and magnetic head-media in magnetic storage devices that operate at high sliding velocities have thus been rendered inadequate. We have developed a new technique to study nanotribological properties at high sliding velocities (up to 10 mm s -1 ) by modifying the commercial AFM set-up. A custom calibrated nanopositioning piezo stage is used for mounting samples and scanning is achieved by providing a triangular input voltage pulse. A capacitive sensor feedback control system is employed to ensure a constant velocity profile during scanning. Friction data are obtained by processing the AFM laser photo-diode signals using a high sampling rate data acquisition card. The utility of the modified set-up for nanoscale friction studies at high sliding velocities is demonstrated using results obtained from various tests performed to study the effect of scan size, rest time, acceleration and velocity on the frictional force for single crystal silicon (100) with native oxide

  8. Magnetic tweezers optimized to exert high forces over extended distances from the magnet in multicellular systems

    Science.gov (United States)

    Selvaggi, L.; Pasakarnis, L.; Brunner, D.; Aegerter, C. M.

    2018-04-01

    Magnetic tweezers are mainly divided into two classes depending on the ability of applying torque or forces to the magnetic probe. We focused on the second category and designed a device composed by a single electromagnet equipped with a core having a special asymmetric profile to exert forces as large as 230 pN-2.8 μm Dynabeads at distances in excess of 100 μm from the magnetic tip. Compared to existing solutions our magnetic tweezers overcome important limitations, opening new experimental paths for the study of a wide range of materials in a variety of biophysical research settings. We discuss the benefits and drawbacks of different magnet core characteristics, which led us to design the current core profile. To demonstrate the usefulness of our magnetic tweezers, we determined the microrheological properties inside embryos of Drosophila melanogaster during the syncytial stage. Measurements in different locations along the dorsal-ventral axis of the embryos showed little variation, with a slight increase in cytoplasm viscosity at the periphery of the embryos. The mean cytoplasm viscosity we obtain by active force exertion inside the embryos is comparable to that determined passively using high-speed video microrheology.

  9. A Facile All-Solution-Processed Surface with High Water Contact Angle and High Water Adhesive Force.

    Science.gov (United States)

    Chen, Mei; Hu, Wei; Liang, Xiao; Zou, Cheng; Li, Fasheng; Zhang, Lanying; Chen, Feiwu; Yang, Huai

    2017-07-12

    A series of sticky superhydrophobicity surfaces with high water contact angle and high water adhesive force is facilely prepared via an all-solution-processed method based on polymerization-induced phase separation between liquid crystals (LCs) and epoxy resin, which produces layers of epoxy microspheres (EMSs) with nanofolds on the surface of a substrate. The morphologies and size distributions of EMSs are confirmed by scanning electron microscopy. Results reveal that the obtained EMS coated-surface exhibits high apparent contact angle of 152.0° and high water adhesive force up to 117.6 μN. By varying the composition of the sample or preparing conditions, the sizes of the produced EMSs can be artificially regulated and, thus, control the wetting properties and water adhesive behaviors. Also, the sticky superhydrophobic surface exhibits excellent chemical stability, as well as long-term durability. Water droplet transportation experiments further prove that the as-made surface can be effectively used as a mechanical hand for water transportation applications. Based on this, it is believed that the simple method proposed in this paper will pave a new way for producing a sticky superhydrophobic surface and obtain a wide range of use.

  10. Long-range forces affecting equilibrium inertial focusing behavior in straight high aspect ratio microfluidic channels

    Energy Technology Data Exchange (ETDEWEB)

    Reece, Amy E.; Oakey, John, E-mail: joakey@uwyo.edu [Department of Chemical Engineering, University of Wyoming, Laramie, Wyoming 82071 (United States)

    2016-04-15

    The controlled and directed focusing of particles within flowing fluids is a problem of fundamental and technological significance. Microfluidic inertial focusing provides passive and precise lateral and longitudinal alignment of small particles without the need for external actuation or sheath fluid. The benefits of inertial focusing have quickly enabled the development of miniaturized flow cytometers, size-selective sorting devices, and other high-throughput particle screening tools. Straight channel inertial focusing device design requires knowledge of fluid properties and particle-channel size ratio. Equilibrium behavior of inertially focused particles has been extensively characterized and the constitutive phenomena described by scaling relationships for straight channels of square and rectangular cross section. In concentrated particle suspensions, however, long-range hydrodynamic repulsions give rise to complex particle ordering that, while interesting and potentially useful, can also dramatically diminish the technique’s effectiveness for high-throughput particle handling applications. We have empirically investigated particle focusing behavior within channels of increasing aspect ratio and have identified three scaling regimes that produce varying degrees of geometrical ordering between focused particles. To explore the limits of inertial particle focusing and identify the origins of these long-range interparticle forces, we have explored equilibrium focusing behavior as a function of channel geometry and particle concentration. Experimental results for highly concentrated particle solutions identify equilibrium thresholds for focusing that scale weakly with concentration and strongly with channel geometry. Balancing geometry mediated inertial forces with estimates for interparticle repulsive forces now provide a complete picture of pattern formation among concentrated inertially focused particles and enhance our understanding of the fundamental limits

  11. Comparison of environmental forcings affecting suspended sediments variability in two macrotidal, highly-turbid estuaries

    Science.gov (United States)

    Jalón-Rojas, Isabel; Schmidt, Sabine; Sottolichio, Aldo

    2017-11-01

    The relative contribution of environmental forcing frequencies on turbidity variability is, for the first time, quantified at seasonal and multiannual time scales in tidal estuarine systems. With a decade of high-frequency, multi-site turbidity monitoring, the two nearby, macrotidal and highly-turbid Gironde and Loire estuaries (west France) are excellent natural laboratories for this purpose. Singular Spectrum Analyses, combined with Lomb-Scargle periodograms and Wavelet Transforms, were applied to the continuous multiannual turbidity time series. Frequencies of the main environmental factors affecting turbidity were identified: hydrological regime (high versus low river discharges), river flow variability, tidal range, tidal cycles, and turbulence. Their relative influences show similar patterns in both estuaries and depend on the estuarine region (lower or upper estuary) and the time scale (multiannual or seasonal). On the multiannual time scale, the relative contribution of tidal frequencies (tidal cycles and range) to turbidity variability decreases up-estuary from 68% to 47%, while the influence of river flow frequencies increases from 3% to 42%. On the seasonal time scale, the relative influence of forcings frequencies remains almost constant in the lower estuary, dominated by tidal frequencies (60% and 30% for tidal cycles and tidal range, respectively); in the upper reaches, it is variable depending on hydrological regime, even if tidal frequencies are responsible for up 50% of turbidity variance. These quantifications show the potential of combined spectral analyses to compare the behavior of suspended sediment in tidal estuaries throughout the world and to evaluate long-term changes in environmental forcings, especially in a context of global change. The relevance of this approach to compare nearby and overseas systems and to support management strategies is discussed (e.g., selection of effective operation frequencies/regions, prediction of the most

  12. Thigh-calf contact parameters for six high knee flexion postures: Onset, maximum angle, total force, contact area, and center of force.

    Science.gov (United States)

    Kingston, David C; Acker, Stacey M

    2018-01-23

    In high knee flexion, contact between the posterior thigh and calf is expected to decrease forces on tibiofemoral contact surfaces, therefore, thigh-calf contact needs to be thoroughly characterized to model its effect. This study measured knee angles and intersegmental contact parameters in fifty-eight young healthy participants for six common high flexion postures using motion tracking and a pressure sensor attached to the right thigh. Additionally, we introduced and assessed the reliability of a method for reducing noise in pressure sensor output. Five repetitions of two squatting, two kneeling, and two unilateral kneeling movements were completed. Interactions of posture by sex occurred for thigh-calf and heel-gluteal center of force, and thigh-calf contact area. Center of force in thigh-calf regions was farther from the knee joint center in females, compared to males, during unilateral kneeling (82 and 67 mm respectively) with an inverted relationship in the heel-gluteal region (331 and 345 mm respectively), although caution is advised when generalizing these findings from a young, relatively fit sample to a population level. Contact area was larger in females when compared to males (mean of 155.61 and 137.33 cm 2 across postures). A posture main effect was observed in contact force and sex main effects were present in onset and max angle. Males had earlier onset (121.0°) and lower max angle (147.4°) with onset and max angles having a range between movements of 8° and 3° respectively. There was a substantial total force difference of 139 N between the largest and smallest activity means. Force parameters measured in this study suggest that knee joint contact models need to incorporate activity-specific parameters when estimating loading. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Cryogenic Impinging Jets Subjected to High Frequency Transverse Acoustic Forcing in a High Pressure Environment

    Science.gov (United States)

    2016-07-27

    generated by a Fluke 292 arbitrary waveform generator. The signal generator was then fed to two Trek PZD2000A high- voltage amplifiers that drove two...Processes of Impinging Jet Injectors,” NASA Propulsion Engineering Research Center, vol. 2, N94-23042, 1993, pp.69-74. 8 Li, R., and Ashgriz...Instability,” NASA SP-194, 1972 V. Appendix A Figure A1. Instantaneous images of an acoustic cycle for the PAN 5 condition. A large group of

  14. Joining forces: collaborating internationally to deliver high-quality, online postgraduate education in pain management.

    Science.gov (United States)

    Devonshire, Elizabeth; Siddall, Philip

    2011-01-01

    The effective management of pain is a complex and costly global issue, requiring a range of innovative educational strategies to enable culturally appropriate and high-quality health care provision. In response to this issue, the Pain Management Research Institute at the University of Sydney (Sydney, Australia) has established several strategic alliances with other overseas universities to deliver online postgraduate education in pain management. The present article discusses the rationale for joining forces, and the approach adopted in creating and maintaining these alliances. It also provides insights into the benefits, challenges and opportunities associated with collaborative educational initiatives of this nature, from institutional, academic and student perspectives.

  15. Real-time nanofabrication with high-speed atomic force microscopy

    International Nuclear Information System (INIS)

    Vicary, J A; Miles, M J

    2009-01-01

    The ability to follow nanoscale processes in real-time has obvious benefits for the future of material science. In particular, the ability to evaluate the success of fabrication processes in situ would be an advantage for many in the semiconductor industry. We report on the application of a previously described high-speed atomic force microscope (AFM) for nanofabrication. The specific fabrication method presented here concerns the modification of a silicon surface by locally oxidizing the region in the vicinity of the AFM tip. Oxide features were fabricated during imaging, with relative tip-sample velocities of up to 10 cm s -1 , and with a data capture rate of 15 fps.

  16. Compensator design for improved counterbalancing in high speed atomic force microscopy.

    Science.gov (United States)

    Bozchalooi, I S; Youcef-Toumi, K; Burns, D J; Fantner, G E

    2011-11-01

    High speed atomic force microscopy can provide the possibility of many new scientific observations and applications ranging from nano-manufacturing to the study of biological processes. However, the limited imaging speed has been an imperative drawback of the atomic force microscopes. One of the main reasons behind this limitation is the excitation of the AFM dynamics at high scan speeds, severely undermining the reliability of the acquired images. In this research, we propose a piezo based, feedforward controlled, counter actuation mechanism to compensate for the excited out-of-plane scanner dynamics. For this purpose, the AFM controller output is properly filtered via a linear compensator and then applied to a counter actuating piezo. An effective algorithm for estimating the compensator parameters is developed. The information required for compensator design is extracted from the cantilever deflection signal, hence eliminating the need for any additional sensors. The proposed approach is implemented and experimentally evaluated on the dynamic response of a custom made AFM. It is further assessed by comparing the imaging performance of the AFM with and without the application of the proposed technique and in comparison with the conventional counterbalancing methodology. The experimental results substantiate the effectiveness of the method in significantly improving the imaging performance of AFM at high scan speeds. © 2011 American Institute of Physics

  17. Implementing Molecular Dynamics for Hybrid High Performance Computers - 1. Short Range Forces

    International Nuclear Information System (INIS)

    Brown, W. Michael; Wang, Peng; Plimpton, Steven J.; Tharrington, Arnold N.

    2011-01-01

    The use of accelerators such as general-purpose graphics processing units (GPGPUs) have become popular in scientific computing applications due to their low cost, impressive floating-point capabilities, high memory bandwidth, and low electrical power requirements. Hybrid high performance computers, machines with more than one type of floating-point processor, are now becoming more prevalent due to these advantages. In this work, we discuss several important issues in porting a large molecular dynamics code for use on parallel hybrid machines - (1) choosing a hybrid parallel decomposition that works on central processing units (CPUs) with distributed memory and accelerator cores with shared memory, (2) minimizing the amount of code that must be ported for efficient acceleration, (3) utilizing the available processing power from both many-core CPUs and accelerators, and (4) choosing a programming model for acceleration. We present our solution to each of these issues for short-range force calculation in the molecular dynamics package LAMMPS. We describe algorithms for efficient short range force calculation on hybrid high performance machines. We describe a new approach for dynamic load balancing of work between CPU and accelerator cores. We describe the Geryon library that allows a single code to compile with both CUDA and OpenCL for use on a variety of accelerators. Finally, we present results on a parallel test cluster containing 32 Fermi GPGPUs and 180 CPU cores.

  18. Compensator design for improved counterbalancing in high speed atomic force microscopy

    Science.gov (United States)

    Bozchalooi, I. S.; Youcef-Toumi, K.; Burns, D. J.; Fantner, G. E.

    2011-11-01

    High speed atomic force microscopy can provide the possibility of many new scientific observations and applications ranging from nano-manufacturing to the study of biological processes. However, the limited imaging speed has been an imperative drawback of the atomic force microscopes. One of the main reasons behind this limitation is the excitation of the AFM dynamics at high scan speeds, severely undermining the reliability of the acquired images. In this research, we propose a piezo based, feedforward controlled, counter actuation mechanism to compensate for the excited out-of-plane scanner dynamics. For this purpose, the AFM controller output is properly filtered via a linear compensator and then applied to a counter actuating piezo. An effective algorithm for estimating the compensator parameters is developed. The information required for compensator design is extracted from the cantilever deflection signal, hence eliminating the need for any additional sensors. The proposed approach is implemented and experimentally evaluated on the dynamic response of a custom made AFM. It is further assessed by comparing the imaging performance of the AFM with and without the application of the proposed technique and in comparison with the conventional counterbalancing methodology. The experimental results substantiate the effectiveness of the method in significantly improving the imaging performance of AFM at high scan speeds.

  19. Recommendations for a National High Blood Pressure Community Education Plan. Report of Task Force III--Community Education.

    Science.gov (United States)

    National Institutes of Health (DHEW), Bethesda, MD. High Blood Pressure Information Center.

    Hypertensive disease being one of the most important medical problems now facing American medicine brought about the formation of the Federally sponsored National High Blood Pressure Education Program, which included four Task Forces. Task Force 3 reviews in this study information and experience useful for the development of guidelines for…

  20. High-speed atomic force microscopy combined with inverted optical microscopy for studying cellular events.

    Science.gov (United States)

    Suzuki, Yuki; Sakai, Nobuaki; Yoshida, Aiko; Uekusa, Yoshitsugu; Yagi, Akira; Imaoka, Yuka; Ito, Shuichi; Karaki, Koichi; Takeyasu, Kunio

    2013-01-01

    A hybrid atomic force microscopy (AFM)-optical fluorescence microscopy is a powerful tool for investigating cellular morphologies and events. However, the slow data acquisition rates of the conventional AFM unit of the hybrid system limit the visualization of structural changes during cellular events. Therefore, high-speed AFM units equipped with an optical/fluorescence detection device have been a long-standing wish. Here we describe the implementation of high-speed AFM coupled with an optical fluorescence microscope. This was accomplished by developing a tip-scanning system, instead of a sample-scanning system, which operates on an inverted optical microscope. This novel device enabled the acquisition of high-speed AFM images of morphological changes in individual cells. Using this instrument, we conducted structural studies of living HeLa and 3T3 fibroblast cell surfaces. The improved time resolution allowed us to image dynamic cellular events.

  1. Insect Repellents: Protect Your Child from Insect Bites

    Science.gov (United States)

    ... Español Text Size Email Print Share Choosing an Insect Repellent for Your Child Page Content Mosquitoes, biting ... sunscreen needs to be reapplied often. Reactions to Insect Repellents If you suspect that your child is ...

  2. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... hair, and nail care Skin care Hair care / hair loss Injured skin Nail care Anti-aging skin care ... hair, and nail care Skin care Hair care / hair loss Injured skin Blisters Bug bites and stings How ...

  3. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Part 1: Structure Part 2: Origin Part 3: Function Textbook Study notes Image library 3-D animated ... nail care Injured skin Bug bites and stings "); (function () { var a = "", b = [ "adid=aad-aad-1", "site= ...

  4. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Excellence in Dermatopathology™ Excellence in Pediatric Dermatology™ Donate Search Menu Donate Member resources and programs Member benefits ... to bites and stings FIND A DERMATOLOGIST Advanced Search "); (function () { var a = "", b = [ "adid=aad-aad-6", " ...

  5. Venomous Snake Bite Injuries at Kitui District Hospital

    African Journals Online (AJOL)

    were school going children who lived in houses mostly made of .... Children and students accounted for 60% of all victims. Farmers 40%. ... family member. Table 1. .... due to its dry and hot climate. .... snake bite and treatment-seeking behavior.

  6. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Choosing Wisely Education Online Learning Center MOC Recognized Credit Basic Derm Curriculum Teaching and learning guides Suggested ... it’s important to take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the ...

  7. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... your head About nails: More important than you think Questions lots of kids ask about their skin, ... bites are harmless, some can spread dangerous diseases like Zika virus, dengue, Lyme disease, and malaria. Particularly ...

  8. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... aging skin care Kids’ zone About skin: Your body's largest organ About hair: Not just on your ... bug bite, such as a rash, fever, or body aches, see your doctor or a board-certified ...

  9. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... to remove a tick How to treat a bee sting When to see a dermatologist Burns Frostbite ... following tips: For painful bites , such as a bee sting, take an over-the-counter painkiller, such ...

  10. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... and treatments Acne and rosacea Bumps and growths Color problems Contagious skin diseases Cosmetic treatments Dry / sweaty ... prevent bug bites, dermatologists recommend the following tips: Use insect repellent. To protect against mosquitoes, ticks and ...

  11. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... and Lectureship Clarence S. Livingood Award and Lectureship Marion B. Sulzberger Award and Lectureship Master Dermatologist Award Members ... skin Bug bites and stings "); (function () { var a = "", b = [ "adid=aad-aad-1", "site=ehs.con.aad. ...

  12. etiology and pathogenesis of anterior open bite: a review

    African Journals Online (AJOL)

    2010-11-11

    Nov 11, 2010 ... bite is essential in the diagnosis, prevention and management of this malocclusion. ... Dental malocclusion may be congenital or develop as the child grows. .... uncommon in maxillofacial patients who present with. Le forte 1 ...

  13. Cryogenic Impinging Jets Subjected to High Frequency Transverse Acoustic Forcing in a High Pressure Environment

    Science.gov (United States)

    2016-07-27

    impingement sheet – Probably due to a impingement point physically moving Distribution A: Approved for Public Release; Distribution Unlimited. PA# 16333 22...AIAA-92- 0458 30th ASM 7. N. Bremond and E. Villermaux, “Atomization by jet impact”, J. Fluid Mech 2006, vol.549, 273-306 8. W.E. Anderson, H. M. Ryan...Sheets formed by Impinging Jets in High Pressure Environments,” AIAA-2004-3526 40th ASM 11. X. Chen, D. Ma, and V. Yang, “Mechanism Study of Impact Wave

  14. Revisiting the blocking force test on ferroelectric ceramics using high energy x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, L., E-mail: laurent.daniel@u-psud.fr [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); GeePs (CNRS UMR8507, CentraleSupelec, UPMC, Univ Paris-Sud), 91192 Gif sur Yvette cedex (France); Hall, D. A.; Withers, P. J. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Koruza, J.; Webber, K. G. [Institute of Materials Science, Technische Universität Darmstadt, Alarich-Weiss-Straße 2, 64287 Darmstadt (Germany); King, A. [European Synchrotron Radiation Facility (ESRF), 6 rue J. Horowitz, 38043 Grenoble (France); Synchrotron SOLEIL, BP 48, 91192 Gif sur Yvette cedex (France)

    2015-05-07

    The blocking force test is a standard test to characterise the properties of piezoelectric actuators. The aim of this study is to understand the various contributions to the macroscopic behaviour observed during this experiment that involves the intrinsic piezoelectric effect, ferroelectric domain switching, and internal stress development. For this purpose, a high energy diffraction experiment is performed in-situ during a blocking force test on a tetragonal lead zirconate titanate (PZT) ceramic (Pb{sub 0.98}Ba{sub 0.01}(Zr{sub 0.51}Ti{sub 0.49}){sub 0.98}Nb{sub 0.02}O{sub 3}). It is shown that the usual macroscopic linear interpretation of the test can also be performed at the single crystal scale, allowing the identification of local apparent piezoelectric and elastic properties. It is also shown that despite this apparent linearity, the blocking force test involves significant non-linear behaviour mostly due to domain switching under electric field and stress. Although affecting a limited volume fraction of the material, domain switching is responsible for a large part of the macroscopic strain and explains the high level of inter- and intra-granular stresses observed during the course of the experiment. The study shows that if apparent piezoelectric and elastic properties can be identified for PZT single crystals from blocking stress curves, they may be very different from the actual properties of polycrystalline materials due to the multiplicity of the physical mechanisms involved. These apparent properties can be used for macroscopic modelling purposes but should be considered with caution if a local analysis is aimed at.

  15. Deep bite malocclusion: exploration of the skeletal and dental factors

    International Nuclear Information System (INIS)

    Bhateja, N.K.; Fida, M.; Shaikh, A.

    2016-01-01

    Correction of deep bite is crucial for maintenance of dental hard and soft tissue structures and for prevention of temporomandibular joint disorders. Exploration of underlying skeletal and dental factors is essential for efficient and individualized treatment planning. To date etiological factors of dental and skeletal deep bite have not been explored in Pakistani orthodontic patients. The objectives of this study were to explore frequencies of dental and skeletal etiological factors in deep bite patients and to determine correlations amongst dental and skeletal etiological factors of deep bite. Methods: The study included a total of 113 subjects (males=35; females=78) with no craniofacial syndromes or prior orthodontic treatment. Pre-treatment orthodontic records were used to evaluate various dental and skeletal parameters. Descriptive statistics of each parameter were calculated. The various study parameters were correlated using Pearson's Correlation. Results: Deep curve of Spee was most frequently seen factor of dental deep bite (72.6%), followed by increased coronal length of upper incisors (28.3%), retroclined upper incisors (17.7%), retroclined lower incisors (8%) and increased coronal length of lower incisors (5.3%). Decreased gonial angle was most commonly found factor of skeletal deep bite (43.4%), followed by decreased mandibular plane angle (27.4%) and maxillary plane's clockwise rotation (26.5%). Frankfort mandibular plane angle and gonial angle showed a strong positive correlation (r=0.66, p=0.000). Conclusions: Reduced gonial angle is most frequently seen skeletal factor, signifying the importance of angulation and growth of ramus in development of deep bite. Deep curve of Spee is most frequently seen dental etiological component in deep bite subjects, hence signifying the importance of intruding the lower anterior teeth. (author)

  16. Habitual biting of oral mucosa: A conservative treatment approach

    Directory of Open Access Journals (Sweden)

    Sarabjot Kaur Bhatia

    2013-01-01

    Full Text Available Chronic biting of oral mucosa is an innocuous self inflicted injury, commonly seen in children suffering from developmental and psychological problems and has rarely been reported in normal unaffected individuals. The management strategies vary from counseling, prescription of sedatives to different prosthetic shields. The paper highlights the efficacy of a simple approach using soft mouth guard in the management of self inflicted lesions due to habitual biting of oral mucosa in two normal healthy children.

  17. The impact of snake bite on household economy in Bangladesh.

    Science.gov (United States)

    Hasan, S M K; Basher, A; Molla, A A; Sultana, N K; Faiz, M A

    2012-01-01

    The present study aims to assess the different types of costs for treatment of snake bite patients, to quantify household economic impact and to understand the coping mechanisms required to cover the costs for snake bite patients in Bangladesh. The patients admitted to four tertiary level hospitals in Bangladesh were interviewed using structured questionnaires including health-care-related expenditures and the way in which the expenditures were covered. Of the snakes which bit the patients, 54.2% were non-venomous, 45.8% were venomous and 42.2% of the patients were given polyvalent antivenom. The total expenditure related to snake bite varies from US$4 (US$1 = Taka 72) to US$2294 with a mean of US$124 and the mean income loss was US$93. Expenditure for venomous snake bite was US$231, which is about seven times higher than non-venomous snake bite (US$34). The treatment imposes a major economic burden on affected families, especially in venomous snake bite cases.

  18. Sensitivity to bites by the bedbug, Cimex lectularius.

    Science.gov (United States)

    Reinhardt, K; Kempke, D; Naylor, R A; Siva-Jothy, M T

    2009-06-01

    Bedbugs are a public health problem and can cause significant economic losses, but little is known about the effects of bites on humans. We reviewed case reports and published papers on bedbug bites to assess the empirical basis of the commonly cited figure that only approximately 80% of the population are sensitive to bedbug bites. We found the sensitivity estimate to be based on only one study carried out 80 years ago. However, this study did not account for the now well-established fact that only repeated exposure to external allergens leads to skin reactions. In our sample, 18 of 19 persons showed a skin reaction after bedbug exposure, but in most cases only after repeated controlled exposure. With repeated exposure, the latency between bite and skin reactions decreased from approximately 10 days to a few seconds. Our results are relevant for the hospitality industry, where apparently increasing infestation rates are likely to lead to an increase in the number of tourists and hotel employees exposed to bedbugs. Medical and public health professionals may expect to see an increase in the prevalence of people with bedbug bite sensitivity. The significance of the delayed reaction time of skin to bites may also have implications in litigation cases where people seek compensation.

  19. Miniature robust five-dimensional fingertip force/torque sensor with high performance

    International Nuclear Information System (INIS)

    Liang, Qiaokang; Huang, Xiuxiang; Li, Zhongyang; Zhang, Dan; Ge, Yunjian

    2011-01-01

    This paper proposes an innovative design and investigation for a five-dimensional fingertip force/torque sensor with a dual annular diaphragm. This sensor can be applied to a robot hand to measure forces along the X-, Y- and Z-axes (F x , F y and F z ) and moments about the X- and Y-axes (M x and M y ) simultaneously. Particularly, the details of the sensing principle, the structural design and the overload protection mechanism are presented. Afterward, based on the design of experiments approach provided by the software ANSYS®, a finite element analysis and an optimization design are performed. These are performed with the objective of achieving both high sensitivity and stiffness of the sensor. Furthermore, static and dynamic calibrations based on the neural network method are carried out. Finally, an application of the developed sensor on a dexterous robot hand is demonstrated. The results of calibration experiments and the application show that the developed sensor possesses high performance and robustness

  20. Single molecule force spectroscopy at high data acquisition: A Bayesian nonparametric analysis

    Science.gov (United States)

    Sgouralis, Ioannis; Whitmore, Miles; Lapidus, Lisa; Comstock, Matthew J.; Pressé, Steve

    2018-03-01

    Bayesian nonparametrics (BNPs) are poised to have a deep impact in the analysis of single molecule data as they provide posterior probabilities over entire models consistent with the supplied data, not just model parameters of one preferred model. Thus they provide an elegant and rigorous solution to the difficult problem encountered when selecting an appropriate candidate model. Nevertheless, BNPs' flexibility to learn models and their associated parameters from experimental data is a double-edged sword. Most importantly, BNPs are prone to increasing the complexity of the estimated models due to artifactual features present in time traces. Thus, because of experimental challenges unique to single molecule methods, naive application of available BNP tools is not possible. Here we consider traces with time correlations and, as a specific example, we deal with force spectroscopy traces collected at high acquisition rates. While high acquisition rates are required in order to capture dwells in short-lived molecular states, in this setup, a slow response of the optical trap instrumentation (i.e., trapped beads, ambient fluid, and tethering handles) distorts the molecular signals introducing time correlations into the data that may be misinterpreted as true states by naive BNPs. Our adaptation of BNP tools explicitly takes into consideration these response dynamics, in addition to drift and noise, and makes unsupervised time series analysis of correlated single molecule force spectroscopy measurements possible, even at acquisition rates similar to or below the trap's response times.

  1. The role of elastic energy in activities with high force and power requirements: a brief review.

    Science.gov (United States)

    Wilson, Jacob M; Flanagan, Eamonn P

    2008-09-01

    The purpose of this article is to provide strength and conditioning practitioners with an understanding of the role of elastic energy in activities with high force and power requirements. Specifically, the article covers 1) the nature of elasticity and its application to human participants, 2) the role of elastic energy in activities requiring a stretch-shorten cycle such as the vertical jump, 3) the role of muscular stiffness in athletic performance, 4) the control of muscular stiffness through feedforward and feedback mechanisms, and 5) factors affecting muscular stiffness. Finally, practical applications are provided. In this section, it is suggested that the storage and reuse of elastic energy is optimized at relatively higher levels of stiffness. Because stiffness decreases as fatigue ensues as well as with stretching before an event, the article emphasizes the need for proper preparation phases in a periodized cycle and the avoidance of long static stretches before high-force activities. The importance of teaching athletes to transition from eccentric to concentric movements with minimal time delays is also proposed due to the finding that time delays appear to decrease the reuse of elastic energy. In addition to teaching within the criterion tasks, evidence is provided that minimizing transitions in plyometric training, a technique demonstrated to increase musculotendinous stiffness, can optimize power output in explosive movements. Finally, evidence is provided that training and teaching programs designed to optimize muscular stiffness may protect athletes against sports-related injuries.

  2. Receptivity and Forced Response to Acoustic Disturbances in High-Speed Boundary Layers

    Science.gov (United States)

    Balakumar, P.; King, Rudolph A.; Chou, Amanda; Owens, Lewis R.; Kegerise, Michael A.

    2016-01-01

    Supersonic boundary-layer receptivity to freestream acoustic disturbances is investigated by solving the Navier-Stokes equations for Mach 3.5 flow over a sharp flat plate and a 7-deg half-angle cone. The freestream disturbances are generated from a wavy wall placed at the nozzle wall. The freestream acoustic disturbances radiated by the wavy wall are obtained by solving the linearized Euler equations. The results for the flat plate show that instability modes are generated at all the incident angles ranging from zero to highly oblique. However, the receptivity coefficient decreases by about 20 times when the incident angle increases from zero to a highly oblique angle of 68 degrees. The results for the cone show that no instability modes are generated when the acoustic disturbances impinge the cone obliquely. The results show that the perturbations generated inside the boundary layer by the acoustic disturbances are the response of the boundary layer to the external forcing. The amplitude of the forced disturbances inside the boundary layer are about 2.5 times larger than the incoming field for zero azimuthal wavenumber and they are about 1.5 times for large azimuthal wavenumbers.

  3. Study of high coercive force films made by vacuum deposition of cobalt onto chromium

    International Nuclear Information System (INIS)

    Randet, Denis

    1969-01-01

    A new method to make high coercive force films, by successive evaporations of chromium and cobalt, was demonstrated in 1966 at the 'Laboratoire d'Electronique et de Technologie de l'Informatique'. This work first contains a description of the magnetic properties of these films according to the conditions of preparation. These properties, which are isotropic in the plane of the film, are then related to the crystallographic structure of chromium and cobalt, in particular through electron microscopy. It is concluded that the coercive force is essentially due to the high magneto-crystalline anisotropy of cobalt in its hexagonal phase and depends, altogether with the shape of the hysteresis loop, on the magnetostatic coupling between the grains, which varies according to their dimensions. The chromium underlayer, if its surface is free enough of oxygen contamination, induces the growth of the hexagonal phase and influences the grain size of cobalt by a sort of epitaxy. At last, the behaviour of the Co/Cr films as a magnetic recording material is briefly examined and discussed. (author) [fr

  4. LLW disposal wasteform preparation in the UK: the role of high force compaction

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L. F.; Fearnley, I. G. [British Nuclear Fuels Ltd., Sellafield (United Kingdom)

    1991-07-01

    British Nuclear Fuels plc (BNFL) owns and operates the principal UK solid low level radioactive waste (LLW) disposal site. The site is located at Drigg in West Cumbria some 6 km to the south east of BNFL's Sellafield reprocessing complex. Sellafield is the major UK generator of LLW, accounting for about 85% of estimated future arisings of raw (untreated, unpackaged) waste. Non-Sellafield consignors to the Drigg site include other BNFL production establishments, nuclear power stations, sites of UKAEA, Ministry of Defence facilities, hospitals, universities, radioisotope production sites and various other industrial organisations. In September 1987, BNFL announced a major upgrade of operations at the Drigg site aimed at improving management practices, the efficiency of space utilisation and enhancing the visual impact of disposal operations. During 1989 a review of plans for compaction and containerisation of Sellafield waste identified that residual voidage in ISO freight containers could be significant even after the introduction of compaction. Subsequent studies which examined a range of compaction and packaging options concluded that the preferred scheme centred on the use of high force compaction (HFC) of compactable waste, and grouting to take up readily accessible voidage in the wasteform. The paper describes the emergence of high force compaction as the preferred scheme for wasteform preparation and subsequent benefits against the background of the overall development of Low Level Waste disposal operations at Drigg.

  5. LLW disposal wasteform preparation in the UK: the role of high force compaction

    International Nuclear Information System (INIS)

    Johnson, L. F.; Fearnley, I. G.

    1991-01-01

    British Nuclear Fuels plc (BNFL) owns and operates the principal UK solid low level radioactive waste (LLW) disposal site. The site is located at Drigg in West Cumbria some 6 km to the south east of BNFL's Sellafield reprocessing complex. Sellafield is the major UK generator of LLW, accounting for about 85% of estimated future arisings of raw (untreated, unpackaged) waste. Non-Sellafield consignors to the Drigg site include other BNFL production establishments, nuclear power stations, sites of UKAEA, Ministry of Defence facilities, hospitals, universities, radioisotope production sites and various other industrial organisations. In September 1987, BNFL announced a major upgrade of operations at the Drigg site aimed at improving management practices, the efficiency of space utilisation and enhancing the visual impact of disposal operations. During 1989 a review of plans for compaction and containerisation of Sellafield waste identified that residual voidage in ISO freight containers could be significant even after the introduction of compaction. Subsequent studies which examined a range of compaction and packaging options concluded that the preferred scheme centred on the use of high force compaction (HFC) of compactable waste, and grouting to take up readily accessible voidage in the wasteform. The paper describes the emergence of high force compaction as the preferred scheme for wasteform preparation and subsequent benefits against the background of the overall development of Low Level Waste disposal operations at Drigg

  6. Mosquito density, biting rate and cage size effects on repellent tests.

    Science.gov (United States)

    Barnard, D R; Posey, K H; Smith, D; Schreck, C E

    1998-01-01

    Mosquito biting rates and the mean duration of protection (in hours) from bites (MDPB) of Aedes aegypti and Anopheles quadrimaculatus, using the repellent 'deet' (N,N-diethyl-3-methylbenzamide) on a 50 cm2 area of healthy human skin, were observed in small (27 l), medium (approximately 65 l) and large (125 l) cages containing low, medium or high densities of mosquitoes: respectively, 640, 128 or 49 cm3 of cage volume per female. At the initial treatment rate of approximately 0.4 microliter/cm2 (1 ml of 25% deet in ethanol on 650 cm2 of skin), the MDPB for deet against Ae. aegypti ranged from 4.5 to 6.5 h and was significantly less (5.0 +/- 0.8 h) in large cages compared with medium (6.2 +/- 0.9 h) and small (6.2 +/- 0.8 h) cages, regardless of the density. Against An. quadrimaculatus the MDPB for deet 0.4 microliter/cm2 was 1.5-8.0 h, less in small (3.7 +/- 2.3 h) and large (2.2 +/- 1.1 h) cages at medium (3.7 +/- 2.3 h) and high (2.5 +/- 1.7 h) mosquito densities, and was longest in medium cages (6.2 +/- 2.6 h) at low mosquito densities (5.8 +/- 2.8 h). With equinoxial photoperiodicity (light on 06.00-18.00 hours) the biting rate was influenced by the time of observation (08.00, 12.00, 16.00 hours) for Ae. aegypti but not for An. quadrimaculatus. For both species, the biting rate was inversely proportional to mosquito density and the MDPB. The shortest MDPBs were obtained in large cages with high densities of mosquitoes and longest protection times occurred in medium sized cages with low mosquito densities.

  7. First report of clinical presentation of a bite by a running spider, Philodromus sp. (Araneae: Philodromidae), with recommendations for spider bite management.

    Science.gov (United States)

    Coetzee, Maureen; Dippenaar, Ansie; Frean, John; Hunt, Richard H

    2017-06-30

    This article describes the clinical progression of symptoms over a period of 5 days of a bite inflicted by a Philodromus sp. spider. Commonly known as 'running spiders', these are not considered to be harmful to humans. This report, however, is the first description of an actual bite by a member of this group of spiders showing cytotoxic envenomation. Management of the bites should be as recommended for other cytotoxic spider bites.

  8. Analysis of Nanodomain Composition in High-Impact Polypropylene by Atomic Force Microscopy-Infrared.

    Science.gov (United States)

    Tang, Fuguang; Bao, Peite; Su, Zhaohui

    2016-05-03

    In this paper, compositions of nanodomains in a commercial high-impact polypropylene (HIPP) were investigated by an atomic force microscopy-infrared (AFM-IR) technique. An AFM-IR quantitative analysis method was established for the first time, which was then employed to analyze the polyethylene content in the nanoscopic domains of the rubber particles dispersed in the polypropylene matrix. It was found that the polyethylene content in the matrix was close to zero and was high in the rubbery intermediate layers, both as expected. However, the major component of the rigid cores of the rubber particles was found to be polypropylene rather than polyethylene, contrary to what was previously believed. The finding provides new insight into the complicated structure of HIPPs, and the AFM-IR quantitative method reported here offers a useful tool for assessing compositions of nanoscopic domains in complex polymeric systems.

  9. Approximate model for toroidal force balance in the high-beta stellarator

    International Nuclear Information System (INIS)

    Barnes, D.C.

    1979-03-01

    A simple model for estimating the body force acting on a diffuse plasma confined in a three-dimensional, high-beta stellarator geometry is given. The equilibrium is treated by an asymptotic expansion about a straight theta pinch with diffuse, circular cross section. The expansion parameter delta is the strength of the applied helical fields. This expansion leads to an inconsistent set of equations for the equilibrium in second order. Nevertheless, by averaging the equilibrium equations over the volume of the confined plasma, a unique condition for toroidal equilibrium is obtained. When the results are compared with the predictions of previous equilibrium theory, which is based on the sharp-boundary model, a large deviation is found. This correction is especially large for l = 0,1 systems at high beta and must be accounted for in any confinement experiment

  10. High intensity interior aircraft noise increases the risk of high diastolic blood pressure in Indonesian Air Force pilots

    Directory of Open Access Journals (Sweden)

    Minarma Siagian

    2009-12-01

    Full Text Available Aim: To analyze the effects of aircraft noise, resting pulse rate, and other factors on the risk of high diastolic blood pressure (DBP in Indonesian Air Force pilots.Methods: A nested case-control study was conducted using data extracted from annual medical check-ups indoctrination aerophysiologic training records at the Saryanto Aviation and Aerospace Health Institute (LAKESPRA in Jakarta from January 2003 – September 2008. For analysis of DBP: the case group with DBP ≥ 90 mmHg were compared with contral group with DBP < 79 mmHG. One case matched to 12 controls.Results: Out of 567 pilots, 544 (95.9% had complete medical records. For this analysis there were 40 cases of high DBP and 480 controls for DBP. Pilots exposed to aircraft noise 90-95 dB rather than 70-80 dB had a 2.7-fold increase for high DBP [adjusted odds ratio (ORa = 2.70; 95% confi dence interval (CI = 1.05-6.97]. Pilots with resting pulse rates of ≥ 81/minute rather than ≤ 80/minute had a 2.7-fold increase for high DBP (ORa = 2.66; 95% CI = 1.26-5.61. In terms of total fl ight hours, pilots who had 1401-11125 hours rather than 147-1400 hours had a 3.2-fold increase for high DBP (ORa = 3.18; 95% CI = 1.01-10.03.Conclusion: High interior aircraft noise, high total flight hours,  and high resting pulse rate, increased risk for high DBP. Self assessment of resting pulse rate can be used to control the risk of high DBP. (Med J Indones 2009; 276: 276-82Keywords: diastolic blood pressure, aircraft noise, resting pulse rate, military pilots

  11. High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise

    Science.gov (United States)

    Macgregor, Lewis J.

    2018-01-01

    Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; pmotor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures. PMID:29630622

  12. DOE Task Force meeting on Electrical Breakdown of Insulating Ceramics in a High Radiation Field

    International Nuclear Information System (INIS)

    Green, P.H.

    1991-08-01

    This volume contains the abstracts and presentation material from the Research Assistance Task Force Meeting ''Electrical Breakdown of Insulating Ceramics in a High-Radiation Field.'' The meeting was jointly sponsored by the Office of Basic Energy Sciences and the Office of Fusion Energy of the US Department of Energy in Vail, Colorado, May 28--June 1, 1991. The 26 participants represented expertise in fusion, radiation damage, electrical breakdown, ceramics, and semiconductor and electronic structures. These participants came from universities, industries, national laboratories, and government. The attendees represented eight nations. The Task Force meeting was organized in response to the recent discovery that a combination of temperature, electric field, and radiation for an extended period of time has an unexplained adverse effect in ceramics, termed radiation-enhanced electrical degradation (REED). REED occurs after an incubation period and continues to accelerate with irradiation until the ceramics can no longer be regarded as insulators. It appears that REED is irreversible and the ceramic insulators cannot be readily annealed or otherwise repaired for future services. This effect poses a serious threat for fusion reactors, which require electrical insulators in diagnostic devices, in radio frequency and neutral beam systems, and in magnetic assemblies. The problem of selecting suitable electrical insulating materials in thus far more serious than previously anticipated

  13. A high-force controllable MR fluid damper–liquid spring suspension system

    International Nuclear Information System (INIS)

    Raja, Pramod; Wang, Xiaojie; Gordaninejad, Faramarz

    2014-01-01

    The goal of the present research is to investigate the feasibility of incorporating a liquid spring in a semi-active suspension system for use in heavy off-road vehicles. A compact compressible magneto-rheological (MR) fluid damper–liquid spring (CMRFD–LS) with high spring rate is designed, developed and tested. Compressible MR fluids with liquid spring and variable damping characteristics are used. These fluids can offer unique functions in reducing the volume/weight of vehicle struts and improving vehicle dynamic stability and safety. The proposed device consists of a cylinder and piston–rod arrangement with an internal annular MR fluid valve. The internal pressures in the chambers on either side of the piston develop the spring force, while the pressure difference across the MR valve produces the damping force, when the fluid flows through the MR valve. Harmonic characterization of the CMRFD–LS is performed and the force–displacement results are presented. A fluid-mechanics based model is also developed to predict the performance of the system at different operating conditions and compared to the experimental results. Good agreement between the experimental results and theoretical predictions has been achieved. (paper)

  14. Stacking it up: Exploring the limits of ultra-high resolution atomic force microscopy

    NARCIS (Netherlands)

    van der Heijden, N.J.

    2017-01-01

    Atomic force microscopy (AFM) is a technique wherein an atomically sharp needle raster scans across a surface, detecting forces between it and the sample. In state-of-the-art AFM experiments the measured forces are typically on the order of pico-Newtons, and the lateral resolution is on the order of

  15. [Infections after bite wounds : For example rat bite fever due to Streptobacillus moniliformis].

    Science.gov (United States)

    Hof, Herbert; Binder, Rudolf; Schäfer, Christian; Stuber, Madeleine; Licht, Andreas; Bozenhardt-Stavrakidis, Iris; Bode, Konrad

    2018-04-11

    Rat bite fever due to Streptobacillus moniliformis induces typical but not pathognomonic clinical signs, such as local purulent wound infection followed by maculopapular exanthema, myalgia as well as purulent joint infections. Severe complications, such as osteomyelitis and endocarditis are possible. it seems that this infection is rarely diagnosed but this infection could be much more common because the final diagnostic proof is difficult to achieve. Firstly, the culture of these bacteria is critical because the bacteria are fastidious and secondly the exact differentiation of the isolates is hardly possible by standard laboratory methods. Modern techniques such as mass spectroscopy (MALDI-TOF) and molecular biology allow a precise clarification. Surgical cleansing of infection sites in combination with a rational antibiotic therapy, for example with beta-lactam antibiotics, are generally able to cure the infection if treatment is started early enough. In addition, vaccinations, for example against tetanus and rabies have to be considered in this situation as for all other bite wound infections.

  16. Impact of Cutting Forces and Chip Microstructure in High Speed Machining of Carbon Fiber – Epoxy Composite Tube

    Directory of Open Access Journals (Sweden)

    Roy Y. Allwin

    2017-09-01

    Full Text Available Carbon fiber reinforced polymeric (CFRP composite materials are widely used in aerospace, automobile and biomedical industries due to their high strength to weight ratio, corrosion resistance and durability. High speed machining (HSM of CFRP material is needed to study the impact of cutting parameters on cutting forces and chip microstructure which offer vital inputs to the machinability and deformation characteristics of the material. In this work, the orthogonal machining of CFRP was conducted by varying the cutting parameters such as cutting speed and feed rate at high cutting speed/feed rate ranges up to 346 m/min/ 0.446 mm/rev. The impact of the cutting parameters on cutting forces (principal cutting, feed and thrust forces and chip microstructure were analyzed. A significant impact on thrust forces and chip segmentation pattern was seen at higher feed rates and low cutting speeds.

  17. Electron beam fabrication and characterization of high-resolution magnetic force microscopy tips

    Science.gov (United States)

    Rührig, M.; Porthun, S.; Lodder, J. C.; McVitie, S.; Heyderman, L. J.; Johnston, A. B.; Chapman, J. N.

    1996-03-01

    The stray field, magnetic microstructure, and switching behavior of high-resolution electron beam fabricated thin film tips for magnetic force microscopy (MFM) are investigated with different imaging modes in a transmission electron microscope (TEM). As the tiny smooth carbon needles covered with a thermally evaporated magnetic thin film are transparent to the electron energies used in these TEMs it is possible to observe both the external stray field emanating from the tips as well as their internal domain structure. The experiments confirm the basic features of electron beam fabricated thin film tips concluded from various MFM observations using these tips. Only a weak but highly concentrated stray field is observed emanating from the immediate apex region of the tip, consistent with their capability for high resolution. It also supports the negligible perturbation of the magnetization sample due to the tip stray field observed in MFM experiments. Investigation of the magnetization distributions within the tips, as well as preliminary magnetizing experiments, confirm a preferred single domain state of the high aspect ratio tips. To exclude artefacts of the observation techniques both nonmagnetic tips and those supporting different magnetization states are used for comparison.

  18. A serial-kinematic nanopositioner for high-speed atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wadikhaye, Sachin P., E-mail: sachin.wadikhaye@uon.edu.au; Yong, Yuen Kuan; Reza Moheimani, S. O. [School of Electrical Engineering and Computer Science, The University of Newcastle, Callaghan, NSW (Australia)

    2014-10-15

    A flexure-guided serial-kinematic XYZ nanopositioner for high-speed Atomic Force Microscopy is presented in this paper. Two aspects influencing the performance of serial-kinematic nanopositioners are studied in this work. First, mass reduction by using tapered flexures is proposed to increased the natural frequency of the nanopositioner. 25% increase in the natural frequency is achieved due to reduced mass with tapered flexures. Second, a study of possible sensor positioning in a serial-kinematic nanopositioner is presented. An arrangement of sensors for exact estimation of cross-coupling is incorporated in the proposed design. A feedforward control strategy based on phaser approach is presented to mitigate the dynamics and nonlinearity in the system. Limitations in design approach and control strategy are discussed in the Conclusion.

  19. Atomic force microscopy study of anion intercalation into highly oriented pyrolytic graphite

    Energy Technology Data Exchange (ETDEWEB)

    Alliata, D; Haering, P; Haas, O; Koetz, R [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Siegenthaler, H [University of Berne (Switzerland)

    1999-08-01

    In the context of ion transfer batteries, we studied highly oriented pyrolytic graphite (HOPG) in perchloric acid, as a model to elucidate the mechanism of electrochemical intercalation in graphite. Aim of the work is the local and time dependent investigation of dimensional changes of the host material during electrochemical intercalation processes on the nanometer scale. We used atomic force microscopy (AFM), combined with cyclic voltammetry, as in-situ tool of analysis during intercalation and expulsion of perchloric anions into the HOPG electrodes. According to the AFM measurements, the HOPG interlayer spacing increases by 32% when perchloric anions intercalate, in agreement with the formation of stage IV of graphite intercalation compounds. (author) 3 figs., 3 refs.

  20. High-speed imaging upgrade for a standard sample scanning atomic force microscope using small cantilevers

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Jonathan D.; Nievergelt, Adrian; Erickson, Blake W.; Yang, Chen; Dukic, Maja; Fantner, Georg E., E-mail: georg.fantner@epfl.ch [Ecole Polytechnique Fédérale de Lausanne, Lausanne (Switzerland)

    2014-09-15

    We present an atomic force microscope (AFM) head for optical beam deflection on small cantilevers. Our AFM head is designed to be small in size, easily integrated into a commercial AFM system, and has a modular architecture facilitating exchange of the optical and electronic assemblies. We present two different designs for both the optical beam deflection and the electronic readout systems, and evaluate their performance. Using small cantilevers with our AFM head on an otherwise unmodified commercial AFM system, we are able to take tapping mode images approximately 5–10 times faster compared to the same AFM system using large cantilevers. By using additional scanner turnaround resonance compensation and a controller designed for high-speed AFM imaging, we show tapping mode imaging of lipid bilayers at line scan rates of 100–500 Hz for scan areas of several micrometers in size.

  1. Serum induced degradation of 3D DNA box origami observed by high speed atomic force microscope

    DEFF Research Database (Denmark)

    Jiang, Zaixing; Zhang, Shuai; Yang, Chuanxu

    2015-01-01

    3D DNA origami holds tremendous potential to encapsulate and selectively release therapeutic drugs. Observations of real-time performance of 3D DNA origami structures in physiological environment will contribute much to its further applications. Here, we investigate the degradation kinetics of 3D...... DNA box origami in serum using high-speed atomic force microscope optimized for imaging 3D DNA origami in real time. The time resolution allows characterizing the stages of serum effects on individual 3D DNA box origami with nanometer resolution. Our results indicate that the whole digest process...... is a combination of a rapid collapse phase and a slow degradation phase. The damages of box origami mainly happen in the collapse phase. Thus, the structure stability of 3D DNA box origami should be further improved, especially in the collapse phase, before clinical applications...

  2. Adsorption and manipulation of carbon onions on highly oriented pyrolytic graphite studied with atomic force microscopy

    International Nuclear Information System (INIS)

    Zhou Jianfeng; Shen Ziyong; Hou Shimin; Zhao Xingyu; Xue Zengquan; Shi Zujin; Gu Zhennan

    2007-01-01

    Carbon onions produced by DC arc discharge method were deposited on highly oriented pyrolytic graphite (HOPG) surface and their adsorption and manipulation was studied using an atomic force microscopy (AFM). Well-dispersed adsorption of carbon onions on HOPG surface was obtained and aggregations of onions were not observed. The van der Waals interaction between the onion and HOPG surface and that between two onions, were calculated and discussed using Hamaker's theory. The manipulation of adsorbed onions on HOPG surface was realized using the AFM in both the raster mode and the vector mode. The controllability and precision of two manipulation modes were compared and the vector mode manipulation was found superior, and is a useful technique for the construction of nano-scale devices based on carbon onions

  3. A serial-kinematic nanopositioner for high-speed atomic force microscopy

    International Nuclear Information System (INIS)

    Wadikhaye, Sachin P.; Yong, Yuen Kuan; Reza Moheimani, S. O.

    2014-01-01

    A flexure-guided serial-kinematic XYZ nanopositioner for high-speed Atomic Force Microscopy is presented in this paper. Two aspects influencing the performance of serial-kinematic nanopositioners are studied in this work. First, mass reduction by using tapered flexures is proposed to increased the natural frequency of the nanopositioner. 25% increase in the natural frequency is achieved due to reduced mass with tapered flexures. Second, a study of possible sensor positioning in a serial-kinematic nanopositioner is presented. An arrangement of sensors for exact estimation of cross-coupling is incorporated in the proposed design. A feedforward control strategy based on phaser approach is presented to mitigate the dynamics and nonlinearity in the system. Limitations in design approach and control strategy are discussed in the Conclusion

  4. Coupled force-balance and particle-occupation rate equations for high-field electron transport

    International Nuclear Information System (INIS)

    Lei, X. L.

    2008-01-01

    It is pointed out that in the framework of balance-equation approach, the coupled force-balance and particle-occupation rate equations can be used as a complete set of equations to determine the high-field transport of semiconductors in both strong and weak electron-electron interaction limits. We call to attention that the occupation rate equation conserves the total particle number and maintains the energy balance of the relative electron system, and there is no need to introduce any other term in it. The addition of an energy-drift term in the particle-occupation rate equation [Phys. Rev. B 71, 195205 (2005)] is physically inadequate for the violation of the total particle-number conservation and the energy balance. It may lead to a substantial unphysical increase of the total particle number by the application of a dc electric field

  5. Unusual presentations of acute kidney injury and neurologic complications due to snake bite

    Directory of Open Access Journals (Sweden)

    Hamid Noshad

    2015-06-01

    Full Text Available Introduction: Vascularity of kidneys is very high, so these organs are potentially susceptible to be affected with toxins including snake venom. Hypersensitivity to snake venous could cause some neurological problem. Case Report: We present a 14-year-old boy with acute kidney injury (AKI due to snake bite. After a few days, kidney failure with hematuria was developed. His serum creatinine level rose to 3 mg/dl and following 2 weeks gradually and decreased to normal level without any special treatment except for anti-venom, which was not prescribed inappropriate time (this type of AKI is not reported previously. He had seizure attacks, which were according to magnetic resonance imaging due to posterior reversible encephalopathy syndrome (PRES (This neurologic complication has been seen in other kidney injuries but up to now it was not reported in snake bite victims. Conclusion: Sanke venom could cause PRES due to AKI and seizure could be one of the most important complications in snake bite.

  6. The health and cost implications of high body mass index in Australian defence force personnel

    Directory of Open Access Journals (Sweden)

    Peake Jonathan

    2012-06-01

    Full Text Available Abstract Background Frequent illness and injury among workers with high body mass index (BMI can raise the costs of employee healthcare and reduce workforce maintenance and productivity. These issues are particularly important in vocational settings such as the military, which require good physical health, regular attendance and teamwork to operate efficiently. The purpose of this study was to compare the incidence of injury and illness, absenteeism, productivity, healthcare usage and administrative outcomes among Australian Defence Force personnel with varying BMI. Methods Personnel were grouped into cohorts according to the following ranges for (BMI: normal (18.5 − 24.9 kg/m2; n = 197, overweight (25–29.9 kg/m2; n = 154 and obese (≥30 kg/m2 with restricted body fat (≤28% for females, ≤24% for males (n = 148 and with no restriction on body fat (n = 180. Medical records for each individual were audited retrospectively to record the incidence of injury and illness, absenteeism, productivity, healthcare usage (i.e., consultation with medical specialists, hospital stays, medical investigations, prescriptions and administrative outcomes (e.g., discharge from service over one year. These data were then grouped and compared between the cohorts. Results The prevalence of injury and illness, cost of medical specialist consultations and cost of medical scans were all higher (p  Conclusions High BMI in the military increases healthcare usage, but does not disrupt workforce maintenance. The greater prevalence of injury and illness, greater healthcare usage and lower productivity in obese Australian Defence Force personnel is not related to higher levels of body fat.

  7. Back pain and its consequences among Polish Air Force pilots flying high performance aircraft

    Directory of Open Access Journals (Sweden)

    Aleksandra Truszczyńska

    2014-04-01

    Full Text Available Objectives: Back pain in Air Force fast jet pilots has been studied by several air forces and found to be relatively common. The objective of the study was to determine the prevalence and degree of the pain intensity in the cervical, thoracic and lumbar spine, subjective risk factors and their effect on the pilots' performance while flying high maneuver aircrafts and the consequences for cognitive deficiencies. Material and Methods: The study was designed as a retrospective, anonymous questionnaire survey, collecting data on the age, aircraft type, flying hours, pain characteristics, physical activity, etc. The study was participated by 94 pilots aged 28-45 years (mean age: 35.9±3.3 years, actively flying fast jet aircrafts Su-22, Mig-29 and F-16. The estimates regarding the level of the subjective back pain were established using visual analogue scales (VAS. Results: The values of the Cochran and Cox T-test for heterogeneous variances are as follows: for the total number of flying hours: F = 2.53, p = 0.0145, for the pilot's age: F = 3.15, p = 0.003, and for the BMI factor F = 2.73, p = 0.008. Conclusions: Our questionnaire survey showed a significant problem regarding spinal conditions in high performance aircraft pilots. The determination of the risk factors may lead to solving this problem and help eliminate the effect of the unfavorable environment on piloting jet aircrafts. Experiencing back pain during the flight might influence the mission performance and flight safety. The costs of pilots education are enormous and inability to fly, or even disability, leads to considerable economic loss. More research on specific prevention strategies is warranted in order to improve the in-flight working environment of fighter pilots.

  8. High-threshold motor unit firing reflects force recovery following a bout of damaging eccentric exercise.

    Science.gov (United States)

    Macgregor, Lewis J; Hunter, Angus M

    2018-01-01

    Exercise-induced muscle damage (EIMD) is associated with impaired muscle function and reduced neuromuscular recruitment. However, motor unit firing behaviour throughout the recovery period is unclear. EIMD impairment of maximal voluntary force (MVC) will, in part, be caused by reduced high-threshold motor unit firing, which will subsequently increase to recover MVC. Fourteen healthy active males completed a bout of eccentric exercise on the knee extensors, with measurements of MVC, rate of torque development and surface electromyography performed pre-exercise and 2, 3, 7 and 14 days post-exercise, on both damaged and control limb. EIMD was associated with decreased MVC (235.2 ± 49.3 Nm vs. 161.3 ± 52.5 Nm; p exercise. Mean motor unit firing rate was reduced (16.4 ± 2.2 Hz vs. 12.6 ± 1.7 Hz; p motor units only, 48h post-exercise, and common drive was elevated (0.36 ± 0.027 vs. 0.56 ± 0.032; pexercise. The firing rate of high-threshold motor units was reduced in parallel with impaired muscle function, whilst early recruited motor units remained unaltered. Common drive of motor units increased in offset to the firing rate impairment. These alterations correlated with the recovery of force decrement, but not of pain elevation. This study provides fresh insight into the central mechanisms associated with EIMD recovery, relative to muscle function. These findings may in turn lead to development of novel management and preventative procedures.

  9. Use of clear aligners in open bite cases: an unexpected treatment option.

    Science.gov (United States)

    Giancotti, Aldo; Garino, Francesco; Mampieri, Gianluca

    2017-06-01

    In open bite case treatments, a proper diagnostic differentiation is essential in determining the appropriate corrective procedures. Dental open bites are generally more responsive to treatment with orthodontics alone, whereas skeletal open bites often require a combination of orthodontics and orthognathic surgery. Patient selection and treatment principles for non-surgical open bite treatment routinely include fixed appliances both labial or lingual. However, removable clear aligners have gained a consistent popularity in the treatment of complex cases including open bite malocclusions. In this article, the authors describe three different clinical cases in which open bite cases had been satisfactorily treated by using clear aligners.

  10. Retrospective Cohort Study to Assess the Risk of Rabies in Biting Dogs, 2013–2015, Republic of Haiti

    Directory of Open Access Journals (Sweden)

    Alexandra M. Medley

    2017-06-01

    .5 95% CI 2.0–10.1, respectively. Rabid dogs were four times more likely to have bitten multiple people (RR = 4.0 95% CI 1.9–8.3. Most rabid dogs died or were killed before quarantine (75% and all died by day 3 of quarantine, compared to <1% of quarantined case-negatives. The greatest risk of death was predicted to be for persons bitten on the head or neck from symptomatic dogs. Bites from dogs deemed healthy by veterinary assessors and which were available for quarantine presented less than a 0.05% risk of rabies death to the victim. Conclusions: Vaccination of all persons exposed to a suspected rabid dog is a highly effective approach to minimize human rabies deaths. However, this may place undue financial burden on bite victims that have had a low-risk exposure and over-prescription may contribute to regional supply shortages. The results here indicate that in a low-resource country such as Haiti, a well-trained veterinary assessor can provide an accurate risk assessment of biting dogs based on a standard case investigation protocol. In canine rabies endemic countries with limited access to PEP, or where PEP costs may cause undue burden on bite victims, structured risk assessments by trained professionals may be a reliable method of triaging PEP for bite victims. Evaluating rabies risk through a matrix of bite location and risk factor in the dog presents a clear delineation of high and low risk encounters and should be used to develop data-derived PEP recommendations.

  11. Evaluation of the clamping force in high tension bolt by using the ultrasonic nonlinearity

    International Nuclear Information System (INIS)

    Jang, Kyung Young; Cheon, Hae Wha; Ha, Hob; Park, Man Sick; Kim, No You

    2005-01-01

    High tension bolts have been used widely for the clamping of many kinds of large structure. Therefore, its estimation has been regarded as main issue in the maintenance of high tension bolts. This paper proposes a novel method using the ultrasonic nonlinearity, which is based on the dependency of sound speed on the stress. For this we introduce nonlinear elastic constants in the stress-strain relationship, and derive the sound speed as a linear function of stress. In order to verify the usefulness of the proposed method, two kinds of experiments are carried out: The first one is to measure the sound speed when the bolt is stressed by the tension tester. The result showed good agreement with the expected linear relationship between the sound speed and the axial stress. The second one is to measure the sound speed when the bolt is stressed by the torque wrench. The results showed that the sound speed was decreased when the torque was increased. From these results we can say that the proposed method is enough useful to evaluate the clamping force in the high tension bolt.

  12. Evaluation of cutting force and surface roughness in high-speed milling of compacted graphite iron

    Directory of Open Access Journals (Sweden)

    Azlan Suhaimi Mohd

    2017-01-01

    Full Text Available Compacted Graphite Iron, (CGI is known to have outstanding mechanical strength and weight-to-strength ratio as compared to conventional grey cast iron, (CI. The outstanding characteristics of CGI is due to its graphite particle shape, which is presented as compacted vermicular particle. The graphite is interconnected with random orientation and round edges, which results in higher mechanical strength. Whereas, graphite in the CI consists of a smooth-surfaced flakes that easily propagates cracks which results in weaker and brittle properties as compared to CGI. Owing to its improved properties, CGI is considered as the best candidate material in substituting grey cast iron that has been used in engine block applications for years. However, the smooth implementation of replacing CI with CGI has been hindered due to the poor machinability of CGI especially at high cutting speed. The tool life is decreased by 20 times when comparing CGI with CI under the same cutting condition. This study investigates the effect of using cryogenic cooling and minimum quantity lubrication (MQL during high-speed milling of CGI (grade 450. Results showed that, the combination of internal cryogenic cooling and enhanced MQL improved the tool life, cutting force and surface quality as compared to the conventional flood coolant strategy during high-speed milling of CGI.

  13. Epidemiological study of insect bite reactions from Central India

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    Sumit Kar

    2013-01-01

    Full Text Available Introduction: The physical effects of the arthropod bites on human skin receive less attention, especially in the rural areas where the per capita income is less. Ours is a rural-based hospital, the vicinity having more of plants, trees, and forests; we undertook the study to find out the relation of insect bite dermatitis in a rural area. Materials and Methods: The study was carried out in the Dermatology outpatient department of our institute on 100 subjects of insect bite dermatitis who were questioned retrospectively about the sequence of events besides their environmental and living conditions. They were examined thoroughly and the relevant clinical findings were noted, also taking into account the prior treatment taken by them, if any. Results and Conclusions: It was found that insect bite dermatitis has no age or gender preponderance, and the protective factors for the same are use of full sleeve clothes and keeping the doors and windows closed at night. On the contrary, the risk factors are residence in areas of heavy insect infestation, use of perfumes and colognes, warm weather in spring and summer and the lack of protective measures. However, there was no direct association of atopy with increased risk of developing insect bite dermatitis.

  14. Facial dog bite injuries in children: A case report

    Directory of Open Access Journals (Sweden)

    Alessandro Leite Cavalcanti

    Full Text Available Introduction: Dog bites are common and can affect victims of different ages, from children to the elderly. Injuries are usually located in different body regions, including head and face. The treatment of choice for injuries is the suture of the lesion, accompanied by antibiotic therapy and tetanus and anti-rabies vaccination. Presentation of case: An 11-year-old male black patient was admitted to the Surgery and Maxillo-Facial Traumatology Service, on an urgent basis, victim of domestic animal aggression (dog biting. The child had multiple and extensive lesions on the face, trauma with laceration with loss of substance, involving the left genic region, lower and upper lip, and lower gingival-labial sulcus. Discussion: Smaller children are especially vulnerable to injuries in the craniofacial region due their low stature, propensity to crawl/play on the ground and exploratory behavior. The primary treatment of bites is by means of direct suture, grafting or local flaps, depending on the type of wound and the surgeon's decision, regardless of time elapsed from the attack. Conclusion: This case shows a case of a child patient victim of animal bite, with lesions limited to the region of the face. The patient was followed up for a month and showed good wound healing without any complications. Keywords: Wounds and injuries, Bites and stings, Maxillofacial injuries, Dogs

  15. Efficacy of topical permethrin as repellent against Aedes aegypti's bites.

    Science.gov (United States)

    Miot, Hélio Amante; Ferreira, Daniela Pinho; Mendes, Fabiana Guandalini; Carrenho, Flávia Roberta Hernandes; de Oliveira Amui, Isabela; Carneiro, Carlos Augusto Sá; Madeira, Newton Goulart

    2008-07-15

    Mosquitoes are the most important vectors of infectious diseases and their bites are related to several adverse skin reactions. Permethrin impregnated clothes are an efficient strategy against arthropods' bites; however, its topical efficacy as a repellent has not been well established. We studied the response to permethrin lotion 5 percent and N,N-Diethyl-meta-toluamide (DEET) spray 50 percent applied to the unprotected forearms of 10 volunteers. Each arm was exposed to 20 female mosquitoes of Aedes aegypti. We performed 71 bilateral comparative measurements evaluating the timing for the first bites. The average times for the arm without the product, with permethrin 5 percent, and with DEET 50 percent were: 7.9 seconds, 336.2 seconds and 7512.1 seconds. The results showed a significant difference between repellency times between either product and unprotected controls. In addition, there was a significant difference in time to first bite between permethrin and DEET treated arms (pAedes aegypti bites in this experimental setting. However, permethrin's profile of repellency was significantly inferior to that of DEET.

  16. Mosquito bite anaphylaxis: immunotherapy with whole body extracts.

    Science.gov (United States)

    McCormack, D R; Salata, K F; Hershey, J N; Carpenter, G B; Engler, R J

    1995-01-01

    Adverse reactions to mosquito bites have been recognized for some time. These usually consist of large local swellings and redness, generalized urticaria, angioedema and less easily definable responses such as nausea, dizziness, headaches, and lethargy. We report two patients who experienced systemic anaphylaxis from mosquito bites. Both were skin tested and given immunotherapy using whole body mosquito extracts. Skin testing using whole body mosquito extracts was positive to Aedes aegypti at 1/1,000 weight/volume (wt/vol) in one patient and to Aedes aegypti at 1/100,000 wt/vol, and Culex pipiens at 1/10,000 wt/vol in the other. Skin testing of ten volunteers without a history of adverse reactions to mosquito bites was negative. Immunotherapy using these extracts resulted in resolution of adverse reactions to mosquito bites in one patient and a decrease in reactions in the other. Immunotherapy with whole body mosquito extracts is a viable treatment option that can play a role in patients with mosquito bite-induced anaphylaxis. It may also result in severe side effects and one must determine the benefit versus risks for each individual patient.

  17. Kissing Bug ( spp. Intrusion into Homes: Troublesome Bites and Domiciliation

    Directory of Open Access Journals (Sweden)

    Stephen A. Klotz

    2016-01-01

    Full Text Available Kissing bugs ( Triatoma spp. frequently enter homes and bite human and pet occupants. Bites may lead to severe allergic reactions and, in some cases, death. Kissing bugs are also vectors of Trypanosoma cruzi , the cause of Chagas disease. In general, modern houses in the United States are not conducive to domiciliation of kissing bugs (bugs living out their entire life within the home with the presence of eggs, nymphs, adults, and exuviae. Construction features such as concrete foundations, solid walls and ceilings, window screens, tight thresholds for doors and windows, and other measures impede bug entry into homes, and air conditioning reduces the need for open doors and windows. Where Chagas disease is endemic in Mexico and Central and South America, homes often have thatch roofs, adobe walls, and open doors and windows. We investigated numerous instances of kissing bug intrusions into homes in Southern Arizona, California, and Louisiana and documented the reactions to kissing bug bites. Our work confirms the importance of modern home construction in limiting kissing bug intrusions. Older homes, especially those lacking modern screening, caulking, and weather stripping to reduce air leakage, may be subject to kissing bug intrusions and domiciliation. We describe a community in Southern Arizona where domiciliation of homes by Triatoma recurva is common. We also provide recent data regarding kissing bug bites and allergic reactions to the bites.

  18. Possible transmission of HIV Infection due to human bite

    Directory of Open Access Journals (Sweden)

    Bandivdekar Atmaram H

    2011-03-01

    Full Text Available Abstract The potential risk of HIV-1 infection following human bite although epidemiologically insignificant, but it is biologically possible. There are anecdotal reports of HIV transmission by human bites particularly if saliva is mixed with blood. The oral tissues support HIV replication and may serve as a previously unrecognized HIV reservoir. The HIV infected individuals have more viruses in blood than saliva, possibly due to the potent HIV-inhibitory properties of saliva. The case presented here is of a primary HIV infections following a human bite where in the saliva was not blood stained but it got smeared on a raw nail bed of a recipient. The blood and saliva of the source and blood of the recipient showed a detectable viral load with 91% sequence homology of C2-V3 region of HIV gp120 between the two individuals. The recipient did not receive PEP [post exposure prophylaxis] as his family physician was unaware of salivary transmission. The family physician should have taken PEP decision after proper evaluation of the severe and bleeding bite. Hence it is necessary to treat the HIV infected human bites with post exposure prophylaxis.

  19. [Prevalence of cross-bite in Mexican children].

    Science.gov (United States)

    Ojeda León, S; De la Teja Angeles, E

    1990-10-01

    As observed, the problem of lining and accommodation of teeth in the child population is increasingly larger. This fact prompted the authors to attempt determining the prevalence of cross-bite in a sample of Mexican children. A total of 306 patients, aged between two and 17 and attending the Stomatology service of the National Institute of Pediatrics, were evaluated, from which all pertinent data regarding age, sex, molar-temporal relationship (terminal, rectus, distal, messial and exaggerated messial planes), permanent molar status (Angle I, II, III), cross-bite, type of dentition affected (primary, mixed or permanent), cross-bite classification (anterior, posterior or mixed), whether unilateral, bilateral, dental or skeletal, right or left, and number of teeth affected, were duly recorded. Out of 306 evaluated patients (160 males, 146 female), 112 evidenced cross-bite (36.6%), 56 of each sex; in 69.6% the teeth were anterior, in 17.8% they were posterior, and in 15.5% their position was mixed. Their average age was 8 years, and malocclusion was Angle class I. From this experience, it is to be concluded that early detection and correction of any dental occlusion abnormality will permit correcting defects in dentofacial development; it is thus necessary to ascertain the frequency of cross-bite.

  20. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Awards World Congress of Dermatology Volunteer opportunities Academy councils, committees, and task forces AccessDerm Camp Discovery Diversity ... MACRA implementation Alternative payment models Fee schedule State policy State policy and action Pending state legislation State ...

  1. A miniaturized, high frequency mechanical scanner for high speed atomic force microscope using suspension on dynamically determined points

    Energy Technology Data Exchange (ETDEWEB)

    Herfst, Rodolf; Dekker, Bert; Witvoet, Gert; Crowcombe, Will; Lange, Dorus de [Department of Optomechatronics, Netherlands Organization for Applied Scientific Research, TNO, Delft (Netherlands); Sadeghian, Hamed, E-mail: hamed.sadeghianmarnani@tno.nl, E-mail: h.sadeghianmarnani@tudelft.nl [Department of Optomechatronics, Netherlands Organization for Applied Scientific Research, TNO, Delft (Netherlands); Department of Precision and Microsystems Engineering, Delft University of Technology, Delft (Netherlands)

    2015-11-15

    One of the major limitations in the speed of the atomic force microscope (AFM) is the bandwidth of the mechanical scanning stage, especially in the vertical (z) direction. According to the design principles of “light and stiff” and “static determinacy,” the bandwidth of the mechanical scanner is limited by the first eigenfrequency of the AFM head in case of tip scanning and by the sample stage in terms of sample scanning. Due to stringent requirements of the system, simply pushing the first eigenfrequency to an ever higher value has reached its limitation. We have developed a miniaturized, high speed AFM scanner in which the dynamics of the z-scanning stage are made insensitive to its surrounding dynamics via suspension of it on specific dynamically determined points. This resulted in a mechanical bandwidth as high as that of the z-actuator (50 kHz) while remaining insensitive to the dynamics of its base and surroundings. The scanner allows a practical z scan range of 2.1 μm. We have demonstrated the applicability of the scanner to the high speed scanning of nanostructures.

  2. Bite-outs and other depletions of mesospheric electrons

    Science.gov (United States)

    Friedrich, Martin; Rapp, Markus; Plane, John M.C.; Torkar, Klaus M.

    2011-01-01

    The ionised mesosphere is less understood than other parts of the ionosphere because of the challenges of making appropriate measurements in this complex region. We use rocket borne in situ measurements of absolute electron density by the Faraday rotation technique and accompanying DC-probe measurements to study the effect of particles on the D-region charge balance. Several examples of electron bite-outs, their actual depth as well as simultaneous observations of positive ions are presented. For a better understanding of the various dependencies we use the ratio β/αi (attachment rate over ion–ion recombination coefficient), derived from the electron and ion density profiles by applying a simplified ion-chemical scheme, and correlate this term with solar zenith angle and moon brightness. The probable causes are different for day and night; recent in situ measurements support existing hypotheses for daytime cases, but also reveal behaviour at night hitherto not reported in the literature. Within the large range of β/αi values obtained from the analysis of 28 high latitude night flights one finds that the intensity of scattered sunlight after sunset, and even moonlight, apparently can photodetach electrons from meteoric smoke particles (MSP) and molecular anions. The large range of values itself can best be explained by the variability of the MSPs and by occasionally occurring atomic oxygen impacting on the negative ion chemistry in the night-time mesosphere under disturbed conditions. PMID:27570472

  3. Cause, setting and ownership analysis of dog bites in Bay County, Florida from 2009 to 2010.

    Science.gov (United States)

    Matthias, J; Templin, M; Jordan, M M; Stanek, D

    2015-02-01

    Emergency room and hospital discharge data have been used to describe the risk factors and public health impact of dog bites. These data sets are based on financial charges for severe bites and underestimates dog bite burdens within communities. This study expands both the source of information and risk factor data collected to provide demographic analysis of dog bite injury risk factors reported in Bay County, Florida in 2009-2010. Extended data for dog bites reported by various sources from January 1, 2009 to December 31, 2010 were collected by Florida Department of Health in Bay County. Data collected included bite victim's age and gender, primary reported cause of bite, setting, dog's restraint status and relationship between the victim and the dog. A total of 799 bites were reported. Most bites (55%) were reported first by healthcare practitioners, particularly bites involving childrenmanagement was the most common cause of bites (26%), followed by protective behaviour (24%). Bites of unknown cause were 2.5 times more likely in childrenrisks by age group or gender provides an opportunity to implement targeted interventions to prevent dog bites. © 2014 Blackwell Verlag GmbH.

  4. Aircraft vibration and other factors related to high systolic blood pressure in Indonesian Air Force pilots

    Directory of Open Access Journals (Sweden)

    Minarma Siagian

    2013-05-01

    Indonesian Air Force pilots doing annual medical check-ups at the Saryanto Institute for Medical and Health Aviation and Aerospace (LAKESPRA from 2003 – 2008. The data extracted from medical records were age, total flight hours, type of aircraft, fasting blood glucose and cholesterol levels, waist circumference, height and weight (Body Mass Index, and blood pressure.Results: Of 336 pilots, there were 16 with systolic pressure  140 mmHg. The pilot who had high vibration than low vibration had 2.8-fold to be high systolic blood pressure [adjusted odds ratio (ORa = 2.83; 95%confidence interval (CI =1.16-22.04. In term of average flight hours, those who had average flight hours of 300-622 hours per year compared to 29-299 hours per year had 5-fold increased risk to be high systolic blood pressure (ORa = 5.05; 95% CI =1.16-22.04]. Furthermore, those who had high than normal resting pulse rate had 2.4 times to be high systolic blood pressure (ORa = 2.37; 95 CI =0.81-6.97; P = 0.115.Conclusion:High aircraft vibration, high average flight hours per year, and high resting pulse rate increase risk high systolic blood pressure in air force pilots.Keywords: systolic blood pressure, aircraft vibration, resting pulse rate, pilots

  5. Fiber Fabry-Perot Force Sensor with Small Volume and High Performance for Assessing Fretting Damage of Steam Generator Tubes.

    Science.gov (United States)

    Huang, Peijian; Wang, Ning; Li, Junying; Zhu, Yong; Zhang, Jie

    2017-12-13

    Measuring the radial collision force between the steam generator tube (SGT) and the tube support plate (TSP) is essential to assess the fretting damage of the SGT. In order to measure the radial collision force, a novel miniaturized force sensor based on fiber Fabry-Perot (F-P) was designed, and the principle and characteristics of the sensor were analyzed in detail. Then, the F-P force sensor was successfully fabricated and calibrated, and the overall dimensions of the encapsulated fiber F-P sensor were 17 mm × 5 mm × 3 mm (L × W × H). The sensor works well in humid, high pressure (10 MPa), high temperature (350 °C), and vibration (40 kHz) environments. Finally, the F-P force sensors were installed in a 1:1 steam generator test loop, and the radial collision force signals between the SGT and the TSP were obtained. The experiments indicated that the F-P sensor with small volume and high performance could help in assessing the fretting damage of the steam generator tubes.

  6. Bite force and sleep quality in patients with bruxism before and after using a mandibular advancement device = Força de mordida e qualidade do sono em pacientes bruxômanos antes e após o uso de placa de avanço mandibular

    Directory of Open Access Journals (Sweden)

    Mainieri, Vivian Chiada

    2008-01-01

    Full Text Available Objetivo: Comparar a força de mordida e a qualidade do sono em pacientes com bruxismo antes e depois do uso de uma placa de avanço mandibular resiliente. Metodologia: Dezoito pacientes com bruxismo em atendimento na Clínica de Oclusão da Faculdade de Odontologia da PUCRS foram selecionados de acordo com os critérios de eligibilidade do estudo, examinados segundo o protocolo RDC/DTM e tratados com uma placa de avanço mandibular resiliente. Antes e após 30 dias de uso da placa de avanço mandibular os sujeitos foram submetidos a testes de força máxima de mordida com um transdutor de força compressiva de arco cruzado posicionado na região de primeiro molar; de qualidade do sono, de acordo com o questionário QAS da Universidade de Toronto; e de contagem do número de contrações do músculo masseter durante o sono usando-se o adesivo BiteStrip®. Os dados foram analisados por teste t de Student, teste de Wilcoxon e teste de McNemar ao nível de significância de 0,05. Resultados: Houve diminuição significativa (P < 0,05 dos parâmetros de bruxismo, de força de mordida e do escore total do QAS após o uso da placa de avanço mandibular por 30 dias. Conclusão: Os resultados sugerem que o uso da placa de avanço mandibular resiliente por um mês reduziu a força de mordida e o bruxismo e melhorou a qualidade do sono nesta amostra

  7. Study on a high thrust force bi-double-sided permanent magnet linear synchronous motor

    Directory of Open Access Journals (Sweden)

    Liang Tong

    2016-03-01

    Full Text Available A high thrust force bi-double-sided permanent magnet linear synchronous motor used in gantry-type five-axis machining center is designed and its performance was tested in this article. This motor is the subproject of Chinese National Science and Technology Major Project named as “development of domestic large thrust linear motor used in high-speed gantry-type five-axis machining center project” jointly participated by enterprises and universities. According to the requirement of the application environment and motor performance parameters, the linear motor’s basic dimensions, form of windings, and magnet arrangement are preliminarily specified through theoretical analysis and calculation. To verify the correctness of the result of the calculation, the finite element model of the motor is established. The static and dynamic characteristics of the motor are studied and analyzed through the finite element method, and the initial scheme is revised. The prototype of the motor is manufactured based on the final revised structure parameters, and the performance of the motor is fully tested using the evaluation platform for direct-drive motor component. Experimental test results meet the design requirements and show the effectiveness of design method and process.

  8. Kawasaki Disease with Retropharyngeal Edema following a Blackfly Bite

    Directory of Open Access Journals (Sweden)

    Toru Watanabe

    2014-01-01

    Full Text Available We describe a patient with Kawasaki disease (KD and retropharyngeal edema following a blackfly bite. An 8-year-old boy was referred to our hospital because of a 3-day-history of fever and left neck swelling and redness after a blackfly bite. Computed tomography of the neck revealed left cervical lymph nodes swelling with edema, increased density of the adjacent subcutaneous tissue layer, and low density of the retropharyngeum. The patient was initially presumed to have cervical cellulitis, lymphadenitis, and retropharyngeal abscess. He was administered antibiotics intravenously, which did not improve his condition. The patient subsequently exhibited other signs of KD and was diagnosed with KD and retropharyngeal edema. Intravenous immunoglobulin therapy and oral flurbiprofen completely resolved the symptoms and signs. A blackfly bite sometimes incites a systemic reaction in humans due to a hypersensitive reaction to salivary secretions, which may have contributed to the development of KD in our patient.

  9. Hypersensitivity to mosquito bite manifested as Skeeter syndrome

    Directory of Open Access Journals (Sweden)

    Rafael Pérez-Vanzzini

    2015-02-01

    Full Text Available The reactions to mosquito bites are immunological reactions with involvement of IgE, IgG and T cells mediated hypersensitivity. These reactions are common and range from small local reactions, large local reactions to systemic allergic reactions. Skeeter syndrome is defined as a large local induced inflammatory reaction to mosquito bite and sometimes accompanied by systemic symptoms such as fever and vomiting. Diagnosis is based on clinical history and physical examination, supported by the identification of specific IgE by skin testing. Treatment includes prevention, antihistamines and steroids in some cases. Specific immunotherapy still requires further study. This paper reports two cases of patients with hypersensitivity reactions to mosquito bites, which were evaluated in our center presenting positive skin tests.

  10. Animal bite injuries to the face : A Case Report.

    Science.gov (United States)

    Simao, Niverso Rodrigues; Borba, Alexandre Meireles; da Silva, Andre Luis Fernandes; Vieira, Evanice Menezes Marcal; Carvalhosa, Artur Aburad; Bandeca, Matheus Coelho; Borges, Alvaro Henrique

    2013-08-01

    Traumatic lacerations to the skin are problems frequently seen and treated by emergency centers around the world. Among all wounds, dog and cat bites are commonly seen. As in many mammals, different species of microorganisms are found in dog and cat mouths with a potential pathological effect to humans, as represented by rabies. The injuries have disfiguration effect with possible psychological repercussion to the patient. This article aimed presenting up to date considerations regarding the management of animal bite injuries to the face, exemplified by a case report that should be the interest of all professions that deal with facial tissues, as dentists do. How to cite this article: Simao NR, Borba AM, da Silva ALF, Vieira EMM, Carvalhosa AA, Bandeca MC, Borges AH. Animal bite injuries to the face: A Case Report. J Int Oral Health 2013; 5(4):68-72.

  11. Effect of wire size on maxillary arch force/couple systems for a simulated high canine malocclusion.

    Science.gov (United States)

    Major, Paul W; Toogood, Roger W; Badawi, Hisham M; Carey, Jason P; Seru, Surbhi

    2014-12-01

    To better understand the effects of copper nickel titanium (CuNiTi) archwire size on bracket-archwire mechanics through the analysis of force/couple distributions along the maxillary arch. The hypothesis is that wire size is linearly related to the forces and moments produced along the arch. An Orthodontic Simulator was utilized to study a simplified high canine malocclusion. Force/couple distributions produced by passive and elastic ligation using two wire sizes (Damon 0.014 and 0.018 inch) measured with a sample size of 144. The distribution and variation in force/couple loading around the arch is a complicated function of wire size. The use of a thicker wire increases the force/couple magnitudes regardless of ligation method. Owing to the non-linear material behaviour of CuNiTi, this increase is less than would occur based on linear theory as would apply for stainless steel wires. The results demonstrate that an increase in wire size does not result in a proportional increase of applied force/moment. This discrepancy is explained in terms of the non-linear properties of CuNiTi wires. This non-proportional force response in relation to increased wire size warrants careful consideration when selecting wires in a clinical setting. © 2014 British Orthodontic Society.

  12. Investigation of polymer derived ceramics cantilevers for application of high speed atomic force microscopy

    Science.gov (United States)

    Wu, Chia-Yun

    High speed Atomic Force Microscopy (AFM) has a wide variety of applications ranging from nanomanufacturing to biophysics. In order to have higher scanning speed of certain AFM modes, high resonant frequency cantilevers are needed; therefore, the goal of this research is to investigate using polymer derived ceramics for possible applications in making high resonant frequency AFM cantilevers using complex cross sections. The polymer derived ceramic that will be studied, is silicon carbide. Polymer derived ceramics offer a potentially more economic fabrication approach for MEMS due to their relatively low processing temperatures and ease of complex shape design. Photolithography was used to make the desired cantilever shapes with micron scale size followed by a wet etching process to release the cantilevers from the substrates. The whole manufacturing process we use borrow well-developed techniques from the semiconducting industry, and as such this project also could offer the opportunity to reduce the fabrication cost of AFM cantilevers and MEMS in general. The characteristics of silicon carbide made from the precursor polymer, SMP-10 (Starfire Systems), were studied. In order to produce high qualities of silicon carbide cantilevers, where the major concern is defects, proper process parameters needed to be determined. Films of polymer derived ceramics often have defects due to shrinkage during the conversion process. Thus control of defects was a central issue in this study. A second, related concern was preventing oxidation; the polymer derived ceramics we chose is easily oxidized during processing. Establishing an environment without oxygen in the whole process was a significant challenge in the project. The optimization of the parameters for using photolithography and wet etching process was the final and central goal of the project; well established techniques used in microfabrication were modified for use in making the cantilever in the project. The techniques

  13. Synchronous fire activity in the tropical high Andes: an indication of regional climate forcing.

    Science.gov (United States)

    Román-Cuesta, R M; Carmona-Moreno, C; Lizcano, G; New, M; Silman, M; Knoke, T; Malhi, Y; Oliveras, I; Asbjornsen, H; Vuille, M

    2014-06-01

    Global climate models suggest enhanced warming of the tropical mid and upper troposphere, with larger temperature rise rates at higher elevations. Changes in fire activity are amongst the most significant ecological consequences of rising temperatures and changing hydrological properties in mountainous ecosystems, and there is a global evidence of increased fire activity with elevation. Whilst fire research has become popular in the tropical lowlands, much less is known of the tropical high Andean region (>2000 masl, from Colombia to Bolivia). This study examines fire trends in the high Andes for three ecosystems, the Puna, the Paramo and the Yungas, for the period 1982-2006. We pose three questions: (i) is there an increased fire response with elevation? (ii) does the El Niño- Southern Oscillation control fire activity in this region? (iii) are the observed fire trends human driven (e.g., human practices and their effects on fuel build-up) or climate driven? We did not find evidence of increased fire activity with elevation but, instead, a quasicyclic and synchronous fire response in Ecuador, Peru and Bolivia, suggesting the influence of high-frequency climate forcing on fire responses on a subcontinental scale, in the high Andes. ENSO variability did not show a significant relation to fire activity for these three countries, partly because ENSO variability did not significantly relate to precipitation extremes, although it strongly did to temperature extremes. Whilst ENSO did not individually lead the observed regional fire trends, our results suggest a climate influence on fire activity, mainly through a sawtooth pattern of precipitation (increased rainfall before fire-peak seasons (t-1) followed by drought spells and unusual low temperatures (t0), which is particularly common where fire is carried by low fuel loads (e.g., grasslands and fine fuel). This climatic sawtooth appeared as the main driver of fire trends, above local human influences and fuel build

  14. Open bite as a risk factor for orthodontic root resorption.

    Science.gov (United States)

    Motokawa, Masahide; Terao, Akiko; Kaku, Masato; Kawata, Toshitsugu; Gonzales, Carmen; Darendeliler, M Ali; Tanne, Kazuo

    2013-12-01

    The purpose of the present study was to clarify the prevalence and degree of root resorption induced by orthodontic treatment in patients with and without open bite. One hundred and eleven patients treated with multibracket appliances were retrospectively selected from the patients and divided into non-open bite (NOB) and open bite (OB) groups. The severity of root resorption and the root shape were classified into five groups on periapical radiographs before and after treatment. Moreover, only in the OB group, all teeth were sub-divided into functional and hypofunctional ones that are occluding and non-occluding. As the results of multiple linear regression analysis of patient characteristics and clinical variables with the number of overall root resorption, the independent variables that were found to contribute significantly to root resorption were bite and abnormal root shape. The prevalences of root resorption evaluated in the number of patients were significantly higher in OB group than in NOB group, and those in the number of teeth were significantly higher in OB group than in NOB group, in particular anterior and premolar teeth. The prevalence of resorbed teeth with abnormal root shapes was also significantly higher in OB group than in NOB group. On the other hand, in OB group, the prevalences of root resorption and teeth with abnormal root shape were significantly greater in hypofunctional teeth than in normal functional teeth. There are more teeth with root resorption and abnormal root shape in open bite cases than in normal bite cases, and more teeth with abnormal root shapes and root resorption in hypofunctional teeth than in functional teeth.

  15. Medicinal plants used to treat Snake bite by Fulani Herdsmen in ...

    African Journals Online (AJOL)

    Dr. Ameen

    the use of village surrounding medicinal plants for the treatment of the snake bite. Recent efforts on ... treatment of snake bites. Information .... Snake venoms are complex mixture of enzymatic and .... treated, mode of diagnosis and medicinal.

  16. Mass awareness regarding snake bite induced early morning neuroparalysis can prevent many deaths in North India

    OpenAIRE

    Sharma, Rupinder; Dogra, Varundeep; Sharma, Gurudutt; Chauhan, Vivek

    2016-01-01

    Introduction: In North India snake bite deaths are predominantly seen with neurotoxic envenomations (NEs) whereas in South India the hemotoxic envenomation (HE) is more common. Krait is responsible for most deaths in North India. It bites people sleeping on the floors, mostly at night. We describe the profile of venomous snake bites over 1 year in 2013. Materials and Methods: The study was conducted in a rural tertiary care hospital in North India. Demographics, circumstances of bite, envenom...

  17. Streptococcus oralis cerebral abscess following monkey bite in a 2-month-old infant.

    Science.gov (United States)

    Thiagarajan, Srinivasan; Krishnamurthy, Sriram; Raghavan, Renitha; Mahadevan, Subramanian; Madhugiri, Venkatesh S; Sistla, Sujatha

    2016-05-01

    Although cerebral abscesses caused by animal bites have been reported, they are extremely rare in infants and have not been described following monkey bite. A 55-day-old male infant presented with a multi-loculated Streptococcus oralis cerebral abscess following a monkey bite on the scalp. There was a clinical response to antibiotic therapy and repeated surgical aspiration followed by a ventriculoperitoneal shunt. This is the first report of a patient with a brain abscess following a monkey bite.

  18. Real-time deflection and friction force imaging by bimorph-based resonance-type high-speed scanning force microscopy in the contact mode.

    Science.gov (United States)

    Cai, Wei; Fan, Haiyun; Zhao, Jianyong; Shang, Guangyi

    2014-01-01

    We report herein an alternative high-speed scanning force microscopy method in the contact mode based on a resonance-type piezoelectric bimorph scanner. The experimental setup, the modified optical beam deflection scheme suitable for smaller cantilevers, and a high-speed control program for simultaneous data capture are described in detail. The feature of the method is that the deflection and friction force images of the sample surface can be obtained simultaneously in real time. Images of various samples (e.g., a test grating, a thin gold film, and fluorine-doped tin oxide-coated glass slides) are acquired successfully. The imaging rate is 25 frames per second, and the average scan speed reaches a value of approximately 2.5 cm/s. The method combines the advantages of both observing the dynamic processes of the sample surface and monitoring the frictional properties on the nanometer scale. 07.79.Lh; 07.79.Sp; 68.37.Ps.

  19. Influence of main forcing affecting the Tagus turbid plume under high river discharges using MODIS imagery.

    Science.gov (United States)

    Fernández-Nóvoa, D; Gómez-Gesteira, M; Mendes, R; deCastro, M; Vaz, N; Dias, J M

    2017-01-01

    The role of river discharge, wind and tide on the extension and variability of the Tagus River plume was analyzed from 2003 to 2015. This study was performed combining daily images obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor located onboard the Aqua and Terra satellites. Composites were generated by averaging pixels with the same forcing conditions. River discharge shows a strong relation with the extension of the Tagus plume. The plume grows with the increasing river discharge and express a two day lag caused by the long residence time of water within the estuary. The Tagus turbid plume was found to be smaller under northerly and easterly winds, than under southerly and westerly winds. It is suggested that upwelling favoring winds provoke the offshore movement of the plume material with a rapidly decrease in turbidity values whereas downwelling favoring winds retain plume material in the north coast close to the Tagus mouth. Eastern cross-shore (oceanward) winds spread the plume seaward and to the north following the coast geometry, whereas western cross-shore (landward) winds keep the plume material in both alongshore directions occupying a large part of the area enclosed by the bay. Low tides produce larger and more turbid plumes than high tides. In terms of fortnightly periodicity, the maximum plume extension corresponding to the highest turbidity is observed during and after spring tides. Minimum plume extension associated with the lowest turbidity occurs during and after neap tides.

  20. Influence of main forcing affecting the Tagus turbid plume under high river discharges using MODIS imagery.

    Directory of Open Access Journals (Sweden)

    D Fernández-Nóvoa

    Full Text Available The role of river discharge, wind and tide on the extension and variability of the Tagus River plume was analyzed from 2003 to 2015. This study was performed combining daily images obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS sensor located onboard the Aqua and Terra satellites. Composites were generated by averaging pixels with the same forcing conditions. River discharge shows a strong relation with the extension of the Tagus plume. The plume grows with the increasing river discharge and express a two day lag caused by the long residence time of water within the estuary. The Tagus turbid plume was found to be smaller under northerly and easterly winds, than under southerly and westerly winds. It is suggested that upwelling favoring winds provoke the offshore movement of the plume material with a rapidly decrease in turbidity values whereas downwelling favoring winds retain plume material in the north coast close to the Tagus mouth. Eastern cross-shore (oceanward winds spread the plume seaward and to the north following the coast geometry, whereas western cross-shore (landward winds keep the plume material in both alongshore directions occupying a large part of the area enclosed by the bay. Low tides produce larger and more turbid plumes than high tides. In terms of fortnightly periodicity, the maximum plume extension corresponding to the highest turbidity is observed during and after spring tides. Minimum plume extension associated with the lowest turbidity occurs during and after neap tides.

  1. High-Reynolds Number Active Blowing Semi-Span Force Measurement System Development

    Science.gov (United States)

    Lynn, Keith C.; Rhew, Ray D.; Acheson, Michael J.; Jones, Gregory S.; Milholen, William E.; Goodliff, Scott L.

    2012-01-01

    Recent wind-tunnel tests at the NASA Langley Research Center National Transonic Facility utilized high-pressure bellows to route air to the model for evaluating aircraft circulation control. The introduction of these bellows within the Sidewall Model Support System significantly impacted the performance of the external sidewall mounted semi-span balance. As a result of this impact on the semi-span balance measurement performance, it became apparent that a new capability needed to be built into the National Transonic Facility s infrastructure to allow for performing pressure tare calibrations on the balance in order to properly characterize its performance under the influence of static bellows pressure tare loads and bellows thermal effects. The objective of this study was to design both mechanical calibration hardware and an experimental calibration design that can be employed at the facility in order to efficiently and precisely perform the necessary loadings in order to characterize the semi-span balance under the influence of multiple calibration factors (balance forces/moments and bellows pressure/temperature). Using statistical design of experiments, an experimental design was developed allowing for strategically characterizing the behavior of the semi-span balance for use in circulation control and propulsion-type flow control testing at the National Transonic Facility.

  2. An exponential universal scaling law for the volume pinning force of high temperature superconductors

    International Nuclear Information System (INIS)

    Hampshire, D.P.

    1993-01-01

    The exponential magnetic field dependence of the critical current density (J c (B,T)) found in many high temperature superconductors, given by: J c (B,T) α(T)exp(-B/β(T)) where α(T) and β(T) are functions of temperature alone, necessarily implies a Universal Scaling Law for the volume pinning force (F p ) of the form: F p /F PMAX exp(+1).(B/β(T)).exp(-B/β(T)). If the Upper Critical Field is not explicitly measured but is artificially determined by smooth extrapolation of J c (B,T) to zero on a linear J c (B,T) vs B plot, this exponential scaling law can be closely approximated by the Kramer dependence given by: F p /F PMAX C.b p .(1-b) q where p = 0.5, q = 2, C ∼ 3.5 and b = B/B C2 (T). The implications for flux pinning studies are discussed. (orig.)

  3. Technique for forcing high Reynolds number isotropic turbulence in physical space

    Science.gov (United States)

    Palmore, John A.; Desjardins, Olivier

    2018-03-01

    Many common engineering problems involve the study of turbulence interaction with other physical processes. For many such physical processes, solutions are expressed most naturally in physical space, necessitating the use of physical space solutions. For simulating isotropic turbulence in physical space, linear forcing is a commonly used strategy because it produces realistic turbulence in an easy-to-implement formulation. However, the method resolves a smaller range of scales on the same mesh than spectral forcing. We propose an alternative approach for turbulence forcing in physical space that uses the low-pass filtered velocity field as the basis of the forcing term. This method is shown to double the range of scales captured by linear forcing while maintaining the flexibility and low computational cost of the original method. This translates to a 60% increase of the Taylor microscale Reynolds number on the same mesh. An extension is made to scalar mixing wherein a scalar field is forced to have an arbitrarily chosen, constant variance. Filtered linear forcing of the scalar field allows for control over the length scale of scalar injection, which could be important when simulating scalar mixing.

  4. The management of dog bite injuries of genitalia in paediatric age ...

    African Journals Online (AJOL)

    Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also ...

  5. Age-related changes in the propensity of dogs to bite.

    Science.gov (United States)

    Messam, L L McV; Kass, P H; Chomel, B B; Hart, L A

    2013-08-01

    This retrospective cohort study was aimed at describing the effects of age at acquisition, age, and duration of ownership of dogs on the risk of (1) bites during play and (2) non-play bites to humans. Data were collected on 110 dogs that had bitten during play with a person, 161 dogs that had bitten outside of play and 951 non-biting dogs from veterinary clients in Kingston (KGN), Jamaica and San Francisco (SF), USA. Modified Poisson regression was employed to model the relationships of both types of bites to each variable separately. Effects of the variables on dog bite risk (1) during and (2) outside of play with the dog, differed from each other and by type of bite. Effects varied with the dog's age and age-related associations were strongest in dogs younger than 1 year old. Ages at acquisition of dogs at highest risk for bites during play were substantially lower than those at risk for non-play bites. Ages and durations of ownership of dogs at highest risk for bites during play were also lower than those of dogs at highest risk for non-play bites. The propensity of a dog to bite changes as it ages and relationships between dog bites occurring during and outside of play and the dog's age at acquisition, current age, and duration of ownership, differ from each other. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. A retrospective review of snake bite victims admitted in a tertiary ...

    African Journals Online (AJOL)

    Objective: Snake bite remains major public health problem worldwide. We present our experience with cases of snake bites managed in our tertiary care teaching center of South India. Materials and Methods: The details of all patients with snake bite admitted to a tertiary teaching care hospital from 2010 to 2012 were ...

  7. High force measurement sensitivity with fiber Bragg gratings fabricated in uniform-waist fiber tapers

    International Nuclear Information System (INIS)

    Wieduwilt, Torsten; Brückner, Sven; Bartelt, Hartmut

    2011-01-01

    Fiber Bragg gratings inscribed in the waist of tapered photosensitive fibers offer specific attractive properties for sensing applications. A small-diameter fiber reduces structural influences for imbedded fiber sensing elements. In the case of application as a force-sensing element for tensile forces, sensitivity scales inversely with the fiber cross-sectional area. It is therefore possible to increase force sensitivity by several orders of magnitude compared to Bragg grating sensors in conventionally sized fibers. Special requirements for such Bragg grating arrangements are discussed and experimental measurements for different fiber taper diameters down to 4 µm are presented

  8. Propagation and Breaking at High Altitudes of Gravity Waves Excited by Tropospheric Forcing

    Science.gov (United States)

    Prusa, Joseph M.; Smolarkiewicz, Piotr K.; Garcia, Rolando R.

    1996-01-01

    An anelastic approximation is used with a time-variable coordinate transformation to formulate a two-dimensional numerical model that describes the evolution of gravity waves. The model is solved using a semi-Lagrangian method with monotone (nonoscillatory) interpolation of all advected fields. The time-variable transformation is used to generate disturbances at the lower boundary that approximate the effect of a traveling line of thunderstorms (a squall line) or of flow over a broad topographic obstacle. The vertical propagation and breaking of the gravity wave field (under conditions typical of summer solstice) is illustrated for each of these cases. It is shown that the wave field at high altitudes is dominated by a single horizontal wavelength; which is not always related simply to the horizontal dimension of the source. The morphology of wave breaking depends on the horizontal wavelength; for sufficiently short waves, breaking involves roughly one half of the wavelength. In common with other studies, it is found that the breaking waves undergo "self-acceleration," such that the zonal-mean intrinsic frequency remains approximately constant in spite of large changes in the background wind. It is also shown that many of the features obtained in the calculations can be understood in terms of linear wave theory. In particular, linear theory provides insights into the wavelength of the waves that break at high altitudes, the onset and evolution of breaking. the horizontal extent of the breaking region and its position relative to the forcing, and the minimum and maximum altitudes where breaking occurs. Wave breaking ceases at the altitude where the background dissipation rate (which in our model is a proxy for molecular diffusion) becomes greater than the rate of dissipation due to wave breaking, This altitude, in effect, the model turbopause, is shown to depend on a relatively small number of parameters that characterize the waves and the background state.

  9. A placebo controlled clinical trial investigating the efficacy of a homeopathic after-bite gel in reducing mosquito bite induced erythema.

    Science.gov (United States)

    Hill, N; Stam, C; Tuinder, S; van Haselen, R A

    1995-01-01

    A randomised, placebo controlled clinical trial was conducted to examine the efficacy of a homeopathic after-bite gel in the symptomatic relief of mosquito bites. Sixty eight healthy volunteers were bitten under laboratory conditions by Aedes aegypti mosquitoes at three spots, on the ventral aspect of the forearm. One bite was treated with the homeopathic after-bite gel, another bite with a placebo gel which was identical in appearance and smell to the homeopathic after-bite gel, and the third bite remained untreated. Immediately after the bites and 1, 3, 6, 26 and 31 hours post-bite, the length and width of the erythema were measured with a calliper, and photographs were taken of the bite sites from which the size of the erythema was subsequently determined. This was followed by assessment of the extent of itching with a verbal analogue scale, and finally treatment took place. For each spot the total erythema was calculated as the area under the plotted curve of the erythema at different time points (mm2*h) and the total sum of the itch scores was determined. For the bites treated with the homeopathic after-bite gel the median total erythema was 10.500 mm2*h. For the spots treated with the placebo gel and the untreated spots the median total erythema was 12.900 mm2*h and 13.300 mm2*h, respectively. The difference between the spots treated with the homeopathic after-bite gel and the untreated spots came close to significance (two-tailed P = 0.06), which was not the case for the difference between the spots treated with the homeopathic after-bite gel and the spots treated with placebo gel (P = 0.13). After pooling the data of a very similar previous pilot study and the present study (ntotal = 83), the homeopathic after-bite gel was significantly superior to no treatment (two-tailed P = 0.003) as well as to placebo gel (two-tailed P = 0.03). Comparing itching after the three treatments, no significant differences could be demonstrated. The extent of itching was

  10. High resolution magnetic force microscopy using focussed ion beam modified tips

    NARCIS (Netherlands)

    Phillips, G.N.; Siekman, Martin Herman; Abelmann, Leon; Lodder, J.C.

    2002-01-01

    Summary form only given. Magnetic force microscopy (MFM) is well established for imaging surface magnetic stray fields. With commercial microscopes and magnetic tips, images with 50 nm resolution are quite routine; however, obtaining higher resolutions is experimentally more demanding. Higher

  11. Control of fingertip forces in young and older adults pressing against fixed low- and high-friction surfaces.

    Directory of Open Access Journals (Sweden)

    Kevin G Keenan

    Full Text Available Mobile computing devices (e.g., smartphones and tablets that have low-friction surfaces require well-directed fingertip forces of sufficient and precise magnitudes for proper use. Although general impairments in manual dexterity are well-documented in older adults, it is unclear how these sensorimotor impairments influence the ability of older adults to dexterously manipulate fixed, low-friction surfaces in particular. 21 young and 18 older (65+ yrs adults produced maximal voluntary contractions (MVCs and steady submaximal forces (2.5 and 10% MVC with the fingertip of the index finger. A Teflon covered custom-molded splint was placed on the fingertip. A three-axis force sensor was covered with either Teflon or sandpaper to create low- and high-friction surfaces, respectively. Maximal downward forces (F(z were similar (p = .135 for young and older adults, and decreased by 15% (p<.001 while pressing on Teflon compared to sandpaper. Fluctuations in F(z during the submaximal force-matching tasks were 2.45× greater (p<.001 for older adults than in young adults, and reached a maximum when older adults pressed against the Teflon surface while receiving visual feedback. These age-associated changes in motor performance are explained, in part, by altered muscle activity from three hand muscles and out-of-plane forces. Quantifying the ability to produce steady fingertip forces against low-friction surfaces may be a better indicator of impairment and disability than the current practice of evaluating maximal forces with pinch meters. These age-associated impairments in dexterity while interacting with low-friction surfaces may limit the use of the current generation of computing interfaces by older adults.

  12. Human biting activity, spatial-temporal distribution and malaria vector role of Anopheles calderoni in the southwest of Colombia.

    Science.gov (United States)

    Orjuela, Lorena I; Ahumada, Martha L; Avila, Ivonni; Herrera, Sócrates; Beier, John C; Quiñones, Martha L

    2015-06-24

    Anopheles calderoni was first recognized in Colombia in 2010 as this species had been misidentified as Anopheles punctimacula due to morphological similarities. An. calderoni is considered a malaria vector in Peru and has been found naturally infected with Plasmodium falciparum in Colombia. However, its biting behaviour, population dynamics and epidemiological importance have not been well described for Colombia. To assess the contribution of An. calderoni to malaria transmission and its human biting behaviour and spatial/temporal distribution in the southwest of Colombia, human landing catches (HLC) and larval collections were carried out in a cross-sectional, entomological study in 22 localities between 2011 and 2012, and a longitudinal study was performed in the Boca de Prieta locality in Olaya Herrera municipality between July 2012 and June 2013. All mosquitoes determined as An. calderoni were tested by ELISA to establish infection with Plasmodium spp. Larvae of An. calderoni were found in four localities in 12 out of 244 breeding sites inspected. An. calderoni adults were collected in 14 out of 22 localities during the cross-sectional study and represented 41.3% (459 of 1,111) of the collected adult specimens. Other species found were Anopheles albimanus (54.7%), Anopheles apicimacula (2.1%), Anopheles neivai (1.7%), and Anopheles argyritarsis (0.2%). In the localities that reported the highest malaria Annual Parasite Index (>10/1,000 inhabitants) during the year of sampling, An. calderoni was the predominant species (>90% of the specimens collected). In the longitudinal study, 1,528 An. calderoni were collected by HLC with highest biting rates in February, May and June 2013, periods of high precipitation. In general, the species showed a preference to bite outdoors (p Colombia. Its observed preference for outdoor biting is a major challenge for malaria control.

  13. Bite Block Vowel Production in Apraxia of Speech

    Science.gov (United States)

    Jacks, Adam

    2008-01-01

    Purpose: This study explored vowel production and adaptation to articulatory constraints in adults with acquired apraxia of speech (AOS) plus aphasia. Method: Five adults with acquired AOS plus aphasia and 5 healthy control participants produced the vowels [iota], [epsilon], and [ash] in four word-length conditions in unconstrained and bite block…

  14. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Particularly if you’re visiting areas with known insect-borne diseases, it’s important to take steps to ... bug bites, dermatologists recommend the following tips: Use insect repellent. To protect against mosquitoes, ticks and other ...

  15. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... 0; c public SPOT Skin Cancer™ Diseases and treatments Skin, hair, and nail care Skin care Hair care / hair loss Injured skin Blisters Bug bites and stings How to remove a tick How to treat a bee sting When to see a dermatologist Burns Frostbite Splinters Treating sunburn Wound care Nail care ...

  16. Innovation in prediction planning for anterior open bite correction.

    Science.gov (United States)

    Almuzian, Mohammed; Almukhtar, Anas; O'Neil, Michael; Benington, Philip; Al Anezi, Thamer; Ayoub, Ashraf

    2015-05-01

    This study applies recent advances in 3D virtual imaging for application in the prediction planning of dentofacial deformities. Stereo-photogrammetry has been used to create virtual and physical models, which are creatively combined in planning the surgical correction of anterior open bite. The application of these novel methods is demonstrated through the surgical correction of a case.

  17. Reconstruction of massive facial avulsive injury, secondary to animal bite.

    Science.gov (United States)

    Motamed, Sadrollah; Niazi, Feizollah; Moosavizadeh, Seyed Mehdi; Gholizade Pasha, Abdolhamid; Motamed, Ali

    2014-02-01

    Management of facial soft tissue trauma requires complex reconstruction surgery. Animal bite on face is a common cause of facial tissue trauma with severe destruction. Evaluation of unit involvement is the first effort, followed by designation of reconstruction. In this case, we performed multiple reconstruction options.

  18. Extreme skeletal open bite correction with vertical elastics.

    Science.gov (United States)

    Cruz-Escalante, Marco Antonio; Aliaga-Del Castillo, Aron; Soldevilla, Luciano; Janson, Guilherme; Yatabe, Marilia; Zuazola, Ricardo Voss

    2017-11-01

    Severe skeletal open bites may be ideally treated with a combined surgical-orthodontic approach. Alternatively, compensations may be planned to camouflage the malocclusion with orthodontics alone. This case report describes the treatment of an 18-year-old man who presented with a severe open bite involving the anterior and posterior teeth up to the first molars, increased vertical dimension, bilateral Class III molar relationship, bilateral posterior crossbite, dental midline deviation, and absence of the maxillary right canine and the mandibular left first premolar. A treatment plan including the extraction of the mandibular right first premolar and based on uprighting and vertical control of the posterior teeth, combined with extrusion of the anterior teeth using multiloop edgewise archwire mechanics and elastics was chosen. After 6 months of alignment and 2 months of multiloop edgewise archwire mechanics, the open bite was significantly reduced. After 24 months of treatment, anterior teeth extrusion, posterior teeth intrusion, and counterclockwise mandibular rotation were accomplished. Satisfactory improvement of the overbite, overjet, sagittal malocclusion, and facial appearance were achieved. The mechanics used in this clinical case demonstrated good and stable results for open-bite correction at the 2-year posttreatment follow-up.

  19. Biting-density and microfilariae infection of Simulium damnosum ...

    African Journals Online (AJOL)

    Investigations on the biting-density and microfilariae infection rate of S. damnosumsl population caught around the Mada River was conducted between May 2013 to April 2014. Captured flies were morphologically identified and dissected for parity and infectivity rate. A total of 308 adult female S. damnosum sl were caught, ...

  20. Bite weight prediction from acoustic recognition of chewing

    NARCIS (Netherlands)

    Amft, O.D.; Kusserow, M.; Tröster, G.

    2009-01-01

    Automatic dietary monitoring (ADM) offers new perspectives to reduce the self-reporting burden for participants in diet coaching programs. This paper presents an approach to predict weight of individual bites taken. We utilize a pattern recognition procedure to spot chewing cycles and food type in

  1. Treatment and outcome of unusual animal bite injuries in young ...

    African Journals Online (AJOL)

    In Philadelphia and New York City, USA, the highest incidences were found .... Mouse. Other. Monkey. 64.8%. 10.1%. 8.8%. 8.2%. 3.8%. 3.1% 1.3%. Fig. 1. Mammalian bite .... development of preventive strategies that target the population at ...

  2. Black and brown widow spider bites in South Africa

    African Journals Online (AJOL)

    JUNIE 1993 ten were adults, 2 were aged 13 - 19 years and 11 were ... back 1). In contrast, 10 of the brown widow bites were on the upper part and 5 on the lower part of the body ..... patient develops generalised muscular pain and cramps,.

  3. Takotsubo cardiomyopathy in a snake bite victim: a case report ...

    African Journals Online (AJOL)

    Takotsubo cardiomyopathy occurs in patients with severe emotional or physiologic stress. The prognosis is usually favorable, and the left ventricular wall motion dyskinesis normalizes within days to weeks. In this paper we report a case of snake bite complicated by takotsubo cardiomyopathy. We advise physicians to ...

  4. Epidemiology of Snake Bites among Selected Communities in the ...

    African Journals Online (AJOL)

    Snake is one of the major group of games feared by people in many localities because of their venoms, yet snakes are equally afraid of human beings. This balance of terror apart from affecting both man and snakes has also led to their deaths. Epidemiology of snake bites among selected communities in the enclave of ...

  5. Convicted by a bite mark, Ted Bundy (1946-1989).

    Science.gov (United States)

    Riaud, Xavier

    2014-01-01

    The identification of a murderer and the eventual conviction was largely due to forensic dentistry and in particular the use of bite marks on the victim compared with casts of the teeth of the accused. The Bundy case has become notorious in American legal circles.

  6. Tick Talk: Block Tick Bites and Lyme Disease

    Science.gov (United States)

    ... this issue Tick Talk Block Tick Bites and Lyme Disease En español Send us your comments When warm ... mainly in the mid-Atlantic and southern states. Lyme disease is the most common tick-borne illness. It’s ...

  7. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... care Injured skin Bug bites and stings "); (function () { var a = "", b = [ "adid=aad-aad-1", "site=ehs. ... t", "hpos=l", "zone=public", "mcat1=de12", ]; for (var c = 0; c "); (function () { var a = "", b = [ "adid= ...

  8. Stability of anterior open-bite treatment with occlusal adjustment.

    Science.gov (United States)

    Janson, Guilherme; Crepaldi, Marcus Vinicius; Freitas, Karina Maria Salvatore; de Freitas, Marcos Roberto; Janson, Waldyr

    2010-07-01

    In this study, we aimed to evaluate the long-term stability of anterior open-bite treatment with occlusal adjustment and the dentinal sensitivity caused by this procedure in the long term. The sample comprised 17 open-bite patients who experienced relapse of the negative vertical overbite after orthodontic treatment and were retreated with occlusal adjustment. The cephalometric changes were evaluated on lateral cephalograms obtained before and after the occlusal adjustment and in the long term (mean, 3.4 years after occlusal adjustment). Dentinal sensitivity was also evaluated before the occlusal adjustment, and 1.35 months, 4.61 months, and 3.4 years later. The cephalometric statuses between the 3 evaluations were compared with analysis of variance (ANOVA) and Tukey tests. The percentages of clinically significant relapse were calculated. To compare dentinal sensitivity at the several stages, nonparametric Friedman and Wilcoxon tests were performed. Statistically significant relapse of anterior open bite occurred in 33.3% of the patients. Those who had the procedure before 21 years of age were most likely to experience relapse. Dentinal sensitivity remained within the normal range in the long term. Despite the statistically significant relapse of anterior open bite, clinically significant stability was found in 66.7% of the patients. Copyright (c) 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  9. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... dress appropriately to prevent bug bites. Cover exposed skin as much as possible by wearing long-sleeved shirts, pants, socks and closed shoes instead of sandals. For additional protection, pull your socks up over your pants and ...

  10. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Mohs AUC MyDermPath+ Psoriasis Patient education resources Practice Management Center Coding and reimbursement Coding MACRA Fee schedule ... it’s important to take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the ...

  11. Acute Generalized Exanthematous Pustulosis (AGEP Triggered by a Spider Bite

    Directory of Open Access Journals (Sweden)

    Michael Makris

    2009-01-01

    Discussion: A spider bite may represent a possible causative factor of AGEP. A spider's venom contains sphingomyelinase that stimulates the release of IL8 and GM-CSF, which are involved in AGEP pathogenesis. Whether or not the con-current use of antibiotics has an effect in AGEP appearance when combined with a spider's venom, cannot be excluded.

  12. Neurological manifestations in speech after snake bite: A rare case ...

    African Journals Online (AJOL)

    Neurological manifestations in speech after snake bite: A rare case. D Vir, D Gupta, M Modi, N Panda. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/pamj.v4i1.53597 · AJOL African Journals Online. HOW TO ...

  13. Bug bites and stings: When to see a dermatologist

    Medline Plus

    Full Text Available ... Private payer Medicare physician payment MACRA implementation Alternative payment models Fee schedule State policy State policy and action ... a dermatologist Why see a board-certified dermatologist? Home Public and patients Skin, hair, and nail care Injured skin Bug bites and stings "); (function () { var ...

  14. Nursing Education in High Blood Pressure Control. Report of the Task Force on the Role of Nursing in High Blood Pressure Control.

    Science.gov (United States)

    National Institutes of Health (DHEW), Bethesda, MD. High Blood Pressure Information Center.

    This curriculum guide on high blood pressure (hypertension) for nursing educators has five sections: (1) Introduction and Objectives provides information regarding the establishment and objectives of the National Task Force on the Role of Nursing in High Blood Pressure Control and briefly discusses nursing's role in hypertension control; (2) Goals…

  15. A novel aptasensor based on single-molecule force spectroscopy for highly sensitive detection of mercury ions.

    Science.gov (United States)

    Li, Qing; Michaelis, Monika; Wei, Gang; Colombi Ciacchi, Lucio

    2015-08-07

    We have developed a novel aptasensor based on single-molecule force spectroscopy (SMFS) capable of detecting mercury ions (Hg(2+)) with sub-nM sensitivity. The single-strand (ss) DNA aptamer used in this work is rich in thymine (T) and readily forms T-Hg(2+)-T complexes in the presence of Hg(2+). The aptamer was conjugated to an atomic force microscope (AFM) probe, and the adhesion force between the probe and a flat graphite surface was measured by single-molecule force spectroscopy (SMFS). The presence of Hg(2+) ions above a concentration threshold corresponding to the affinity constant of the ions for the aptamer (about 5 × 10(9) M(-1)) could be easily detected by a change of the measured adhesion force. With our chosen aptamer, we could reach an Hg(2+) detection limit of 100 pM, which is well below the maximum allowable level of Hg(2+) in drinking water. In addition, this aptasensor presents a very high selectivity for Hg(2+) over other metal cations, such as K(+), Ca(2+), Zn(2+), Fe(2+), and Cd(2+). Furthermore, the effects of the ionic strength and loading rate on the Hg(2+) detection were evaluated. Its simplicity, reproducibility, high selectivity and sensitivity make our SMFS-based aptasensor advantageous with respect to other current Hg(2+) sensing methods. It is expected that our strategy can be exploited for monitoring the pollution of water environments and the safety of potentially contaminated food.

  16. An isometric muscle force estimation framework based on a high-density surface EMG array and an NMF algorithm

    Science.gov (United States)

    Huang, Chengjun; Chen, Xiang; Cao, Shuai; Qiu, Bensheng; Zhang, Xu

    2017-08-01

    Objective. To realize accurate muscle force estimation, a novel framework is proposed in this paper which can extract the input of the prediction model from the appropriate activation area of the skeletal muscle. Approach. Surface electromyographic (sEMG) signals from the biceps brachii muscle during isometric elbow flexion were collected with a high-density (HD) electrode grid (128 channels) and the external force at three contraction levels was measured at the wrist synchronously. The sEMG envelope matrix was factorized into a matrix of basis vectors with each column representing an activation pattern and a matrix of time-varying coefficients by a nonnegative matrix factorization (NMF) algorithm. The activation pattern with the highest activation intensity, which was defined as the sum of the absolute values of the time-varying coefficient curve, was considered as the major activation pattern, and its channels with high weighting factors were selected to extract the input activation signal of a force estimation model based on the polynomial fitting technique. Main results. Compared with conventional methods using the whole channels of the grid, the proposed method could significantly improve the quality of force estimation and reduce the electrode number. Significance. The proposed method provides a way to find proper electrode placement for force estimation, which can be further employed in muscle heterogeneity analysis, myoelectric prostheses and the control of exoskeleton devices.

  17. Comparative Biomechanical Modeling of Metatherian and Placental Saber-Tooths: A Different Kind of Bite for an Extreme Pouched Predator.

    Science.gov (United States)

    Wroe, Stephen; Chamoli, Uphar; Parr, William C H; Clausen, Philip; Ridgely, Ryan; Witmer, Lawrence

    2013-01-01

    Questions surrounding the dramatic morphology of saber-tooths, and the presumably deadly purpose to which it was put, have long excited scholarly and popular attention. Among saber-toothed species, the iconic North American placental, Smilodon fatalis, and the bizarre South American sparassodont, Thylacosmilus atrox, represent extreme forms commonly forwarded as examples of convergent evolution. For S. fatalis, some consensus has been reached on the question of killing behaviour, with most researchers accepting the canine-shear bite hypothesis, wherein both head-depressing and jaw closing musculatures played a role in delivery of the fatal bite. However, whether, or to what degree, T. atrox may have applied a similar approach remains an open question. Here we apply a three-dimensional computational approach to examine convergence in mechanical performance between the two species. We find that, in many respects, the placental S. fatalis (a true felid) was more similar to the metatherian T. atrox than to a conical-toothed cat. In modeling of both saber-tooths we found that jaw-adductor-driven bite forces were low, but that simulations invoking neck musculature revealed less cranio-mandibular stress than in a conical-toothed cat. However, our study also revealed differences between the two saber-tooths likely reflected in the modus operandi of the kill. Jaw-adductor-driven bite forces were extremely weak in T. atrox, and its skull was even better-adapted to resist stress induced by head-depressors. Considered together with the fact that the center of the arc described by the canines was closer to the jaw-joint in Smilodon, our results are consistent with both jaw-closing and neck musculature playing a role in prey dispatch for the placental, as has been previously suggested. However, for T. atrox, we conclude that the jaw-adductors probably played no major part in the killing bite. We propose that the metatherian presents a more complete commitment to the already

  18. Quantification of the resist dissolution process: an in situ analysis using high speed atomic force microscopy

    Science.gov (United States)

    Santillan, Julius Joseph; Shichiri, Motoharu; Itani, Toshiro

    2016-03-01

    This work focuses on the application of a high speed atomic force microscope (HS-AFM) for the in situ visualization / quantification of the resist dissolution process. This technique, as reported in the past, has provided useful pointers on the formation of resist patterns during dissolution. This paper discusses about an investigation made on the quantification of what we refer to as "dissolution unit size" or the basic units of patterning material dissolution. This was done through the establishment of an originally developed analysis method which extracts the difference between two succeeding temporal states of the material film surface (images) to indicate the amount of change occurring in the material film at a specific span of time. Preliminary experiments with actual patterning materials were done using a positive-tone EUV model resist composed only of polyhydroxystyrene (PHS)-based polymer with a molecular weight of 2,500 and a polydispersity index of 1.2. In the absence of a protecting group, the material was utilized at a 50nm film thickness with post application bake of 90°C/60s. The resulting film is soluble in the alkali-based developer even without exposure. Results have shown that the dissolution components (dissolution unit size) of the PHS-based material are not of fixed size. Instead, it was found that aside from one constantly dissolving unit size, another, much larger dissolution unit size trend also occurs during material dissolution. The presence of this larger dissolution unit size suggests an occurrence of "polymer clustering". Such polymer clustering was not significantly present during the initial stages of dissolution (near the original film surface) but becomes more persistently obvious after the dissolution process reaches a certain film thickness below the initial surface.

  19. Monsoonal response to mid-holocene orbital forcing in a high resolution GCM

    Directory of Open Access Journals (Sweden)

    J. H. C. Bosmans

    2012-04-01

    Full Text Available In this study, we use a sophisticated high-resolution atmosphere-ocean coupled climate model, EC-Earth, to investigate the effect of Mid-Holocene orbital forcing on summer monsoons on both hemispheres. During the Mid-Holocene (6 ka, there was more summer insolation on the Northern Hemisphere than today, which intensified the meridional temperature and pressure gradients. Over North Africa, monsoonal precipitation is intensified through increased landward monsoon winds and moisture advection as well as decreased moisture convergence over the oceans and more convergence over land compared to the pre-industrial simulation. Precipitation also extends further north as the ITCZ shifts northward in response to the stronger poleward gradient of insolation. This increase and poleward extent is stronger than in most previous ocean-atmosphere GCM simulations. In north-westernmost Africa, precipitation extends up to 35° N. Over tropical Africa, internal feedbacks completely overcome the direct warming effect of increased insolation. We also find a weakened African Easterly Jet. Over Asia, monsoonal precipitation during the Mid-Holocene is increased as well, but the response is different than over North-Africa. There is more convection over land at the expense of convection over the ocean, but precipitation does not extend further northward, monsoon winds over the ocean are weaker and the surrounding ocean does not provide more moisture. On the Southern Hemisphere, summer insolation and the poleward insolation gradient were weaker during the Mid-Holocene, resulting in a reduced South American monsoon through decreased monsoon winds and less convection, as well as an equatorward shift in the ITCZ. This study corroborates the findings of paleodata research as well as previous model studies, while giving a more detailed account of Mid-Holocene monsoons.

  20. The management of dog bite injuries of genitalia in paediatric age

    Directory of Open Access Journals (Sweden)

    Mirko Bertozzi

    2013-01-01

    Full Text Available Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also directly related to the severity of initial wound. Guidelines for the management of dog bites include irrigation, dιbridment, antibiotic therapy, consideration of tetanus and rabies immunisation and suture of wounds or surgical reconstruction. Literature review was conducted and focused to analyze the management of dog bite lesions involving external genitalia.

  1. Open Fracture of the Forearm Bones due to Horse Bite

    Directory of Open Access Journals (Sweden)

    John Ashutosh Santoshi

    2014-01-01

    Full Text Available Introduction: Fractures have been described mainly following falling accidents in horse-related injuries. Horse bites are uncommon accidents. We present a case of open fracture of the forearm due to horse bite. Case Report: A 35-year-old male farm-worker presented to the emergency room with alleged history of horse bite to the right forearm about 2 hours prior to presentation while feeding the horse. There was deformity of the forearm with multiple puncture wounds, deep abrasions and small lacerations on the distal-third of the forearm. Copious irrigation with normal saline was done and he was administered anti-tetanus and post-exposure rabies prophylaxis. Prophylactic antibiotic therapy was commenced. Radiographs revealed fracture of radius and ulna in the mid-shaft region. He underwent emergency wound debridement, and the ulna was stabilised with an intra-medullary square nail. Seventy-two hours later, he underwent re-debridement and conversion osteosynthesis. He had an uneventful recovery and at three-month follow-up, the fractures had healed radiographically in anatomic alignment. At two-year follow-up, he is doing well, is pain free and has a normal range of motion compared to the contralateral side. Conclusion: Horse bites behave as compound fractures however rabies prophylaxis will be needed and careful observation is needed. Early radical debridement, preliminary skeletal stabilisation, re-debridement and conversion osteosynthesis to plate, and antibiotic prophylaxis were the key to the successful management of our patient. Keywords: Horse; animal bite; forearm; open fracture

  2. Final Report of the National Black Health Providers Task Force on High Blood Pressure Education and Control.

    Science.gov (United States)

    Public Health Service (DHHS), Rockville, MD.

    This is the final report of National Black Health Providers Task Force (NBHPTF) on High Blood Pressure Education and Control. The first chapter of the report recounts the history of the NBHPTF and its objectives. In the second chapter epidemiological evidence is presented to demonstrate the need for a suggested 20 year plan aimed at controlling…

  3. How not to train your dragon: a case of a Komodo dragon bite.

    Science.gov (United States)

    Borek, Heather A; Charlton, Nathan P

    2015-06-01

    Komodo dragons (Varanus komodoensis) are the world's largest lizards, known for killing prey that exceed their body mass. Reports of bites to humans in the popular press suggest high degrees of morbidity and mortality. Reports in the medical literature are lacking. We describe the case of a zookeeper who was bitten by a Komodo dragon, with a resultant mallet finger. We further discuss the various potential mechanisms of Komodo dragon lethality, including sepsis and venom deposition theories that are useful in guiding management. Copyright © 2015 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  4. Instantaneous axial force of a high-order Bessel vortex beam of acoustic waves incident upon a rigid movable sphere.

    Science.gov (United States)

    Mitri, F G; Fellah, Z E A

    2011-08-01

    The present investigation examines the instantaneous force resulting from the interaction of an acoustical high-order Bessel vortex beam (HOBVB) with a rigid sphere. The rigid sphere case is important in fluid dynamics applications because it perfectly simulates the interaction of instantaneous sound waves in a reduced gravity environment with a levitated spherical liquid soft drop in air. Here, a closed-form solution for the instantaneous force involving the total pressure field as well as the Bessel beam parameters is obtained for the case of progressive, stationary and quasi-stationary waves. Instantaneous force examples for progressive waves are computed for both a fixed and a movable rigid sphere. The results show how the instantaneous force per unit cross-sectional surface and unit pressure varies versus the dimensionless frequency ka (k is the wave number in the fluid medium and a is the sphere's radius), the half-cone angle β and the order m of the HOBVB. It is demonstrated here that the instantaneous force is determined only for (m,n) = (0,1) (where n is the partial-wave number), and vanishes for m>0 because of symmetry. In addition, the instantaneous force and normalized amplitude velocity results are computed and compared with those of a rigid immovable (fixed) sphere. It is shown that they differ significantly for ka values below 5. The proposed analysis may be of interest in the analysis of instantaneous forces on spherical particles for particle manipulation, filtering, trapping and drug delivery. The presented solutions may also serve as a method for comparison to other solutions obtained by strictly numerical or asymptotic approaches. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Performance of Cableless Magnetic In-Piping Actuator Capable of High-Speed Movement by Means of Inertial Force

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yaguchi

    2011-01-01

    Full Text Available The present paper proposes a novel cableless magnetic actuator with a new propulsion module that exhibits a very high thrusting force. This actuator contains an electrical inverter that directly transforms DC from button batteries into AC. The electrical DC-AC inverter incorporates a mass-spring system, a reed switch, and a curved permanent magnet that switches under an electromagnetic force. The actuator is moved by the inertial force of the mass-spring system due to mechanical resonance energy. The experimental results show that the actuator is able to move upward at a speed of 19.7 mm/s when using 10 button batteries when pulling a 20 g load mass. This cableless magnetic actuator has several possible applications, including narrow pipe inspection and maintenance.

  6. Estimation of the local response to a forcing in a high dimensional system using the fluctuation-dissipation theorem

    Directory of Open Access Journals (Sweden)

    F. C. Cooper

    2013-04-01

    Full Text Available The fluctuation-dissipation theorem (FDT has been proposed as a method of calculating the response of the earth's atmosphere to a forcing. For this problem the high dimensionality of the relevant data sets makes truncation necessary. Here we propose a method of truncation based upon the assumption that the response to a localised forcing is spatially localised, as an alternative to the standard method of choosing a number of the leading empirical orthogonal functions. For systems where this assumption holds, the response to any sufficiently small non-localised forcing may be estimated using a set of truncations that are chosen algorithmically. We test our algorithm using 36 and 72 variable versions of a stochastic Lorenz 95 system of ordinary differential equations. We find that, for long integrations, the bias in the response estimated by the FDT is reduced from ~75% of the true response to ~30%.

  7. On the force relaxation in the magnetic levitation system with a high-Tc superconductor

    International Nuclear Information System (INIS)

    Smolyak, B M; Zakharov, M S

    2014-01-01

    The effect of magnetic flux creep on the lift force in a magnet/superconductor system was studied. It was shown experimentally that in the case of real levitation (when a levitating object bears only on a magnetic field) the suspension height and consequently the lift force did not change over a long period of time. When the levitating object is fixed for some time (i.e. a rigid constraint is imposed on it), the levitation height decreases after removal of the external constraint. It is assumed that free oscillations of the levitating object slow down the flux creep process, which is activated when these oscillations are suppressed. (paper)

  8. Optimal design of high damping force engine mount featuring MR valve structure with both annular and radial flow paths

    International Nuclear Information System (INIS)

    Nguyen, Q H; Choi, S B; Lee, Y S; Han, M S

    2013-01-01

    This paper focuses on the optimal design of a compact and high damping force engine mount featuring magnetorheological fluid (MRF). In the mount, a MR valve structure with both annular and radial flows is employed to generate a high damping force. First, the configuration and working principle of the proposed MR mount is introduced. The MRF flows in the mount are then analyzed and the governing equations of the MR mount are derived based on the Bingham plastic behavior of the MRF. An optimal design of the MR mount is then performed to find the optimal structure of the MR valve to generate a maximum damping force with certain design constraints. In addition, the gap size of MRF ducts is empirically chosen considering the ‘lockup’ problem of the mount at high frequency. Performance of the optimized MR mount is then evaluated based on finite element analysis and discussions on performance results of the optimized MR mount are given. The effectiveness of the proposed MR engine mount is demonstrated via computer simulation by presenting damping force and power consumption. (paper)

  9. Fabrication of high-aspect-ratio microstructures using dielectrophoresis-electrocapillary force-driven UV-imprinting

    International Nuclear Information System (INIS)

    Li, Xiangming; Shao, Jinyou; Tian, Hongmiao; Ding, Yucheng; Li, Xiangmeng

    2011-01-01

    We propose a novel method for fabricating high-aspect-ratio micro-/nano-structures by dielectrophoresis-electrocapillary force (DEP-ECF)-driven UV-imprinting. The force of DEP-ECF, acting on an air–liquid interface and an air–liquid–solid three-phase contact line, is generated by applying voltage between an electrically conductive mold and a substrate, and tends to pull the dielectric liquid (a UV-curable pre-polymer) into the mold micro-cavities. The existence of DEP-ECF is explained theoretically and demonstrated experimentally by the electrically induced reduction of the contact angle. Furthermore, DEP-ECF is proven to play a critical role in forcing the polymer to fill into the mold cavities by the real-time observation of the dynamic filling process. Using the DEP-ECF-driven UV-imprinting process, high-aspect-ratio polymer micro-/nano-structures (more than 10:1) are fabricated with high consistency. This patterning method can overcome the drawbacks of the mechanically induced mold deformation and position shift in conventional imprinting lithography and maximize the pattern uniformity which is usually poor in capillary force lithography

  10. Optimal design of high damping force engine mount featuring MR valve structure with both annular and radial flow paths

    Science.gov (United States)

    Nguyen, Q. H.; Choi, S. B.; Lee, Y. S.; Han, M. S.

    2013-11-01

    This paper focuses on the optimal design of a compact and high damping force engine mount featuring magnetorheological fluid (MRF). In the mount, a MR valve structure with both annular and radial flows is employed to generate a high damping force. First, the configuration and working principle of the proposed MR mount is introduced. The MRF flows in the mount are then analyzed and the governing equations of the MR mount are derived based on the Bingham plastic behavior of the MRF. An optimal design of the MR mount is then performed to find the optimal structure of the MR valve to generate a maximum damping force with certain design constraints. In addition, the gap size of MRF ducts is empirically chosen considering the ‘lockup’ problem of the mount at high frequency. Performance of the optimized MR mount is then evaluated based on finite element analysis and discussions on performance results of the optimized MR mount are given. The effectiveness of the proposed MR engine mount is demonstrated via computer simulation by presenting damping force and power consumption.

  11. High temperature reactor: Driving force to convert CO2 to fuel - HTR2008-58132

    International Nuclear Information System (INIS)

    McCormick, J. L.

    2008-01-01

    The rapidly increasing cost of petroleum products and uncertainty of long-term supply have prompted the U.S. military to aggressively pursue production of alternative fuels (synfuels) such as coal-to-liquids (CTL). U.S. Air Force is particularly active in this effort while the entire military is involved in simultaneously developing fuel specifications for alternative fuels that enable a single fuel for the entire battle space; all ground vehicles, aircraft and fuel cells. By limiting its focus on coal, tar sands and oil shale resources, the military risks violating federal law which requires the use of synfuels that have life cycle greenhouse gas emissions less than or equal to emissions from conventional petroleum fuels. A climate-friendly option would use a high temperature nuclear reactor to split water. The hydrogen (H 2 ) would be used in the reverse water gas shift (RWGS) to react with carbon dioxide (CO 2 ) to produce carbon monoxide (CO) and water. The oxygen (O 2 ) would be fed into a supercritical (SC) coal furnace. The flue gas CO 2 emissions would be stripped of impurities before reacting with H 2 in a RWGS process. Resultant carbon monoxide (CO) is fed, with additional H2, (extra H 2 needed to adjust the stoichiometry: 2 moles H 2 to one mole CO) into a conventional Fischer-Tropsch synthesis (FTS) to produce a heavy wax which is cracked and isomerized and refined to Jet Propulsion 8 (JP-8) and Jet Propulsion 5 (JP-5) fuels. The entire process offers valuable carbon-offsets and multiple products that contribute to lower syn-fuel costs and to comply with the federal limitation imposed on syn-fuel purchases. While the entire process is not commercially available, component parts are being researched; their physical and chemical properties understood and some are state-of-the-art technologies. An international consortium should complete physical, chemical and economic flow sheets to determine the feasibility of this concept that, if pursued, has broad

  12. Self-Centering Seismic Lateral Force Resisting Systems: High Performance Structures for the City of Tomorrow

    Directory of Open Access Journals (Sweden)

    Nathan Brent Chancellor

    2014-09-01

    Full Text Available Structures designed in accordance with even the most modern buildings codes are expected to sustain damage during a severe earthquake; however; these structures are expected to protect the lives of the occupants. Damage to the structure can require expensive repairs; significant business downtime; and in some cases building demolition. If damage occurs to many structures within a city or region; the regional and national economy may be severely disrupted. To address these shortcomings with current seismic lateral force resisting systems and to work towards more resilient; sustainable cities; a new class of seismic lateral force resisting systems that sustains little or no damage under severe earthquakes has been developed. These new seismic lateral force resisting systems reduce or prevent structural damage to nonreplaceable structural elements by softening the structural response elastically through gap opening mechanisms. To dissipate seismic energy; friction elements or replaceable yielding energy dissipation elements are also included. Post-tensioning is often used as a part of these systems to return the structure to a plumb; upright position (self-center after the earthquake has passed. This paper summarizes the state-of-the art for self-centering seismic lateral force resisting systems and outlines current research challenges for these systems.

  13. Elastic-properties measurement at high temperatures through contact resonance atomic force microscopy

    DEFF Research Database (Denmark)

    Marinello, Francesco; Pezzuolo, Andrea; Carmignato, Simone

    2015-01-01

    fast direct and non-destructive measurement of Young's modulus and related surface parameters.In this work an instrument set up for Contact Resonance Atomic Force Microscopy is proposed, where the sample with is coupled to a heating stage and a piezoelectric transducer directly vibrate the cantilever...

  14. Experimental Contribution to High-Precision Characterization of Magnetic Forces in Active Magnetic Bearings

    DEFF Research Database (Denmark)

    Kjølhede, Klaus; Santos, Ilmar

    2007-01-01

    of the magnetic forces is conducted using different experimental tests: (i) by using hall sensors mounted directly on the poles (precise measurements of the magnetic flux) and by an auxiliary system, composed of strain gages and flexible beams attached to the rotor (ii) by measuring the input current and bearing...

  15. High resolution magnetic force microscopy: instrumentation and application for recording media

    NARCIS (Netherlands)

    Porthun, Steffen; Porthun, S.

    This thesis describes aspects of the use of magnetic force microscopy for the study of magnetic recording media. The maximum achievable storage density in magnetic recording is limited by the magnetic reversal behaviour of the medium and by the stability of the written information. The shape and

  16. Electron beam fabrication and characterization of high- resolution magnetic force microscopy tips

    NARCIS (Netherlands)

    Ruhrig, M.; Rührig, M.; Porthun, S.; Porthun, S.; Lodder, J.C.; Mc vitie, S.; Heyderman, L.J.; Johnston, A.B.; Chapman, J.N.

    1996-01-01

    The stray field, magnetic microstructure, and switching behavior of high‐resolution electron beam fabricated thin film tips for magnetic force microscopy (MFM) are investigated with different imaging modes in a transmission electron microscope (TEM). As the tiny smooth carbon needles covered with a

  17. All you can eat: high performance capacity and plasticity in the common big-eared bat, Micronycteris microtis (Chiroptera: Phyllostomidae).

    Science.gov (United States)

    Santana, Sharlene E; Geipel, Inga; Dumont, Elizabeth R; Kalka, Margareta B; Kalko, Elisabeth K V

    2011-01-01

    Ecological specialization and resource partitioning are expected to be particularly high in the species-rich communities of tropical vertebrates, yet many species have broader ecological niches than expected. In Neotropical ecosystems, Neotropical leaf-nosed bats (Phyllostomidae) are one of the most ecologically and functionally diverse vertebrate clades. Resource partitioning in phyllostomids might be achieved through differences in the ability to find and process food. We selected Micronycteris microtis, a very small (5-7 g) animalivorous phyllostomid, to explore whether broad resource use is associated with specific morphological, behavioral and performance traits within the phyllostomid radiation. We documented processing of natural prey and measured bite force in free-ranging M. microtis and other sympatric phyllostomids. We found that M. microtis had a remarkably broad diet for prey size and hardness. For the first time, we also report the consumption of vertebrates (lizards), which makes M. microtis the smallest carnivorous bat reported to date. Compared to other phyllostomids, M. microtis had the highest bite force for its size and cranial shape and high performance plasticity. Bite force and cranial shape appear to have evolved rapidly in the M. microtis lineage. High performance capacity and high efficiency in finding motionless prey might be key traits that allow M. microtis, and perhaps other species, to successfully co-exist with other gleaning bats.

  18. All you can eat: high performance capacity and plasticity in the common big-eared bat, Micronycteris microtis (Chiroptera: Phyllostomidae.

    Directory of Open Access Journals (Sweden)

    Sharlene E Santana

    Full Text Available Ecological specialization and resource partitioning are expected to be particularly high in the species-rich communities of tropical vertebrates, yet many species have broader ecological niches than expected. In Neotropical ecosystems, Neotropical leaf-nosed bats (Phyllostomidae are one of the most ecologically and functionally diverse vertebrate clades. Resource partitioning in phyllostomids might be achieved through differences in the ability to find and process food. We selected Micronycteris microtis, a very small (5-7 g animalivorous phyllostomid, to explore whether broad resource use is associated with specific morphological, behavioral and performance traits within the phyllostomid radiation. We documented processing of natural prey and measured bite force in free-ranging M. microtis and other sympatric phyllostomids. We found that M. microtis had a remarkably broad diet for prey size and hardness. For the first time, we also report the consumption of vertebrates (lizards, which makes M. microtis the smallest carnivorous bat reported to date. Compared to other phyllostomids, M. microtis had the highest bite force for its size and cranial shape and high performance plasticity. Bite force and cranial shape appear to have evolved rapidly in the M. microtis lineage. High performance capacity and high efficiency in finding motionless prey might be key traits that allow M. microtis, and perhaps other species, to successfully co-exist with other gleaning bats.

  19. Simulation-Driven Development and Optimization of a High-Performance Six-Dimensional Wrist Force/Torque Sensor

    Directory of Open Access Journals (Sweden)

    Qiaokang LIANG

    2010-05-01

    Full Text Available This paper describes the Simulation-Driven Development and Optimization (SDDO of a six-dimensional force/torque sensor with high performance. By the implementation of the SDDO, the developed sensor possesses high performance such as high sensitivity, linearity, stiffness and repeatability simultaneously, which is hard for tranditional force/torque sensor. Integrated approach provided by software ANSYS was used to streamline and speed up the process chain and thereby to deliver results significantly faster than traditional approaches. The result of calibration experiment possesses some impressive characters, therefore the developed fore/torque sensor can be usefully used in industry and the methods of design can also be used to develop industrial product.

  20. High quality NMR structures: a new force field with implicit water and membrane solvation for Xplor-NIH

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Ye [Sanford-Burnham-Prebys Medical Discovery Institute (United States); Schwieters, Charles D. [National Institutes of Health, Center for Information Technology (United States); Opella, Stanley J. [University of California San Diego, Department of Chemistry and Biochemistry (United States); Marassi, Francesca M., E-mail: fmarassi@sbmri.org [Sanford-Burnham-Prebys Medical Discovery Institute (United States)

    2017-01-15

    Structure determination of proteins by NMR is unique in its ability to measure restraints, very accurately, in environments and under conditions that closely mimic those encountered in vivo. For example, advances in solid-state NMR methods enable structure determination of membrane proteins in detergent-free lipid bilayers, and of large soluble proteins prepared by sedimentation, while parallel advances in solution NMR methods and optimization of detergent-free lipid nanodiscs are rapidly pushing the envelope of the size limit for both soluble and membrane proteins. These experimental advantages, however, are partially squandered during structure calculation, because the commonly used force fields are purely repulsive and neglect solvation, Van der Waals forces and electrostatic energy. Here we describe a new force field, and updated energy functions, for protein structure calculations with EEFx implicit solvation, electrostatics, and Van der Waals Lennard-Jones forces, in the widely used program Xplor-NIH. The new force field is based primarily on CHARMM22, facilitating calculations with a wider range of biomolecules. The new EEFx energy function has been rewritten to enable OpenMP parallelism, and optimized to enhance computation efficiency. It implements solvation, electrostatics, and Van der Waals energy terms together, thus ensuring more consistent and efficient computation of the complete nonbonded energy lists. Updates in the related python module allow detailed analysis of the interaction energies and associated parameters. The new force field and energy function work with both soluble proteins and membrane proteins, including those with cofactors or engineered tags, and are very effective in situations where there are sparse experimental restraints. Results obtained for NMR-restrained calculations with a set of five soluble proteins and five membrane proteins show that structures calculated with EEFx have significant improvements in accuracy, precision