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Sample records for high bite forces

  1. Instrument for measuring human biting force

    Science.gov (United States)

    Kopola, Harri K.; Mantyla, Olavi; Makiniemi, Matti; Mahonen, Kalevi; Virtanen, Kauko

    1995-02-01

    Alongside EMG activity, biting force is the primary parameter used for assessing the biting problems of dentulous patients and patients with dentures. In a highly conductive oral cavity, dielectric measurement methods are preferred, for safety reasons. The maximum biting force for patients with removable dentures is not more than 100 ... 300 N. We report here on an instrument developed for measuring human biting force which consists of three units: a mouthpiece, a signal processing and interface unit (SPI), and a PC. The mouthpiece comprises a sensor head of thickness 3.4 mm, width 20 mm and length 30 mm constructed of two stainless steel plates and with a fiber optic microbending sensor between them. This is connected to the SPI unit by a three-meter fiber optic cable, and the SPI unit to the PC by an RS connection. A computer program has been developed that includes measurement, display, zeroing, and calibration operations. The instrument measures biting force as a function of time and displays the time-dependent force profile and maximum force on a screen or plots it in hard copy. The dynamic measurement range of the mouthpiece is from 0 to 1000 N, and the resolution of the instrument is 10 N. The results of preliminary clinical measurements and repeatability tests are reported.

  2. Bite force and state of dentition.

    Science.gov (United States)

    Helkimo, E; Carlsson, G E; Helkimo, M

    1977-01-01

    The maximal bite force and the strength of the finger-thumb grip of 125 Skolt Lapps, aged 15 to 65, was measured with a specially devised apparatus. The bite force was measured with the biting fork placed between the first molars and between the incisors, respectively. The finger-thumb grip was measured by letting the subject press the prongs of the fork between the thumb and forefinger of each hand as hard as possible. The range of inter-individual variation of the maximal bite force and finger-thumb grip was great. The mean values were higher for the males than for the females. In the males the maximal bite force thus measured in the molar region was 39 kg (382 N) and 18 kg (176 N) in the incisor region. The corresponding values for the females were 22 kg (216 N) and 11 kg (108 N). The finger-thumb grip strength for males was, on the average, 10 kg (98 N); that of the females, 7 KG (69 N). The average difference in bite force between the men and the women was larger in the group with natural teeth than in the one with complete dentures. The values found for the bite force decreased with increasing age, especially for the females. Most of this reduction with increasing age was probably due to the age-dependent deterioration of the dentition. In both sexes the bite force was notably smaller among the denture wearers than among the dentate persons. The number of natural teeth varied closely with the bite force, i.e. the greater number of natural teeth the greater the bite force.

  3. An Innovative Miniature Bite Force Recorder.

    Science.gov (United States)

    Singh, Sarabjeet; Utreja, Ashok K; Sandhu, Navreet; Dhaliwal, Yadvinder S

    2011-01-01

    In this study, a detailed description of development of a new novel bite force recorder (gnathodynamometer) using solid state components is vividly explained. This state of the art authenticated device can be used to assess the complex function of human bite force, which is the net resultant combination of functional response of various craniomandibular structures consisting of interrelated components, like the muscles of mastication, joints, teeth and the neuromuscular system. The consistency and accuracy of the bite force recorder was reaffirmed by doing a detailed laboratory calibration and clinical testing on 30 adult subjects.

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

    Science.gov (United States)

    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

  5. Novel Low-Cost Sensor for Human Bite Force Measurement

    Directory of Open Access Journals (Sweden)

    Jarred Fastier-Wooller

    2016-08-01

    Full Text Available This paper presents the design and development of a low cost and reliable maximal voluntary bite force sensor which can be manufactured in-house by using an acrylic laser cutting machine. The sensor has been designed for ease of fabrication, assembly, calibration, and safe use. The sensor is capable of use within an hour of commencing production, allowing for rapid prototyping/modifications and practical implementation. The measured data shows a good linear relationship between the applied force and the electrical resistance of the sensor. The output signal has low drift, excellent repeatability, and a large measurable range of 0 to 700 N. A high signal-to-noise response to human bite forces was observed, indicating the high potential of the proposed sensor for human bite force measurement.

  6. Task-dependence of activity/ bite-force relations and its impact on estimation of chewing force from EMG.

    Science.gov (United States)

    Proeschel, P A; Morneburg, T

    2002-07-01

    Estimation of chewing force from electromyograms (EMGs) calibrated in isometric biting yielded strikingly high force values. We tested the hypothesis that EMG-based force predictions are excessive because of differing activity/bite-force relations in mastication and isometric biting. In nine patients, unilateral bite forces and EMGs of 4 elevator muscles were recorded during chewing and isometric clenching on a bite-fork. We estimated chewing force by substituting chewing EMGs of each muscle into isometric activity/bite-force regressions. The estimates were compared with actual chewing forces recorded by intra-oral transducers. In all muscles except the balancing-side masseter, the activity/bite-force ratio was significantly higher in chewing than in isometric biting. The actual mean chewing force amounted to 220 N, while EMG-based estimates ranged from 273 to 475 N, depending on the muscle used for estimation. The results indicate that different activity/force characteristics in dynamic and isometric biting can cause overestimation when chewing force is predicted from masticatory EMGs.

  7. A Study of Bite Force and Various Variables in Children Segregated by Angle's Classification

    Science.gov (United States)

    Sandhu, Navreet; Kashyap, Rita

    2012-01-01

    ABSTRACT The stomatographic system has been studied by several researchers, yet it is still unclear, weather a genetically determined facial morphology decides the strength of masticatory muscles,1 or weather a strong musculature influences the form of the face. This formed the basis of present study to relate muscle activity with various malocclusions. Thus, 60 samples of younger age group were divided according to Angle classification and maximum bite force was recorded among the groups. Newly designed bite force recorder was used for recording bite force at molar and at incisal region. Influence of various independent variables like gender, overjet and overbite of the subjects on the bite force was also checked. It was concluded that maximum bite force at intercuspal position (molar) and anterior bite position (incisal) were not significantly different between normal, class I, class II div 1 and class III malocclusion groups. There was no significant correlation between incisal bite force and overjet or overbite, but there was a highly significant difference (p < 0.001) between the males and females for maximum bite force at intercuspal position, with males biting harder than the females. How to cite this article: Singh S, Sandhu N, Kashyap R. A Study of Bite Force and Various Variables in Children Segregated by Angle's Classification. Int J Clin Pediatr Dent 2012;5(2):118-123. PMID:25206150

  8. 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.

  9. Proximate determinants of bite force in Anolis lizards.

    Science.gov (United States)

    Wittorski, Antoine; Losos, Jonathan B; Herrel, Anthony

    2016-01-01

    Performance measures associated with the vertebrate jaw system may provide important insights into vertebrate ecology and evolution because of their importance in many ecologically relevant tasks. Previous studies have shown that in many taxa, evolution toward higher bite force has gone hand in hand with the evolution of larger body size. However, independent of differences in overall body size, bite force may vary depending on head size and shape as well. Moreover, the underlying musculature may also drive variation in bite force. Here, we investigate the proximate determinants of bite force in lizards of the genus Anolis. We dissected the jaw muscles and quantified muscle mass, fibre length, and cross-sectional area. Data were analysed for both sexes independently given the sexual dimorphism detected in the dataset. Our results show that the traits that explain bite force are similar in both males and females with overall body size and muscle mass being the principal determinants. Among the different muscles examined, the adductor externus and the pseudotemporalis groups were the best determinants of bite force. However, models run for males predicted the variation in bite force better than models for females, suggesting that selection on morphology improving bite force may be stronger in males. © 2015 Anatomical Society.

  10. Mechanics of bite force production and its relationship to diet in bats

    National Research Council Canada - National Science Library

    Sharlene E. Santana; Elizabeth R. Dumont; Julian L. Davis

    2010-01-01

    .... Mechanistic studies of bite force production have identified morphological features associated with bite force, and linked bite force with diet, but this approach has rarely been used in mammals. 2...

  11. Bite force is limited by the force-length relationship of skeletal muscle in black carp, Mylopharyngodon piceus.

    Science.gov (United States)

    Gidmark, Nicholas J; Konow, Nicolai; Lopresti, Eric; Brainerd, Elizabeth L

    2013-04-23

    Bite force is critical to feeding success, especially in animals that crush strong, brittle foods. Maximum bite force is typically measured as one value per individual, but the force-length relationship of skeletal muscle suggests that each individual should possess a range of gape height-specific, and, therefore, prey size-specific, bite forces. We characterized the influence of prey size on pharyngeal jaw bite force in the snail-eating black carp (Mylopharyngodon piceus, family Cyprinidae), using feeding trials on artificial prey that varied independently in size and strength. We then measured jaw-closing muscle lengths in vivo for each prey size, and then determined the force-length relationship of the same muscle in situ using tetanic stimulations. Maximum bite force was surprisingly high: the largest individual produced nearly 700 N at optimal muscle length. Bite force decreased on large and small prey, which elicited long and short muscle lengths, respectively, demonstrating that the force-length relationship of skeletal muscle results in prey size-specific bite force.

  12. Can masticatory electromyography be normalised to submaximal bite force?

    Science.gov (United States)

    Crawford, S R; Burden, A M; Yates, J M; Zioupos, P; Winwood, K

    2015-05-01

    The combination of bite force and jaw muscle electromyography (EMG) provides an insight into the performance of the stomatognathic system, especially in relation to dynamic movement tasks. Literature has extensively investigated possible methods for normalising EMG data encapsulating many different approaches. However, bite force literature trends towards normalising EMG to a maximal voluntary contraction (MVC), which could be difficult for ageing populations or those with poor dental health or limiting conditions such as temporomandibular disorder. The objectives of this study were to (i) determine whether jaw-closing muscle activity is linearly correlated with incremental submaximal and maximal bite force levels and (ii) assess whether normalising maximal and submaximal muscle activity to that produced when performing a low submaximal bite force (20 N) improves repeatability of EMG values. Thirty healthy adults (15 men, 15 women; mean age 21 ± 1·2 years) had bite force measurements obtained using a custom-made button strain gauge load cell. Masseter and anterior temporalis muscle activities were collected bilaterally using surface EMG sensors whilst participants performed maximal biting and three levels of submaximal biting. Furthermore, a small group (n = 4 females) were retested for reliability purposes. Coefficients of variation and intra-class correlation coefficients showed markedly improved reliability when EMG data were normalised compared to non-normalised. This study shows that jaw muscle EMG may be successfully normalised to a very low bite force. This may open possibilities for comparisons between at-risk sample groups that may otherwise find it difficult to produce maximal bite force values.

  13. EMG, bite force, and elongation of the masseter muscle under isometric voluntary contractions and variations of vertical dimension.

    Science.gov (United States)

    Manns, A; Miralles, R; Palazzi, C

    1979-12-01

    The relation EMG activity, bite force, and muscular elongation was studied in eight subjects with complete natural dentition during isometric contractions of the masseter muscle, measured from 7 mm to almost maximum jaw opening. EMG was registered with superficial electrodes and bite force with a gnathodynamometer. In series 1, recordings of EMG activity maintaining bite force constant (10 and 20 kg) show that EMG is high when the bite opening is 7 mm, decreases from 15 to 20 mm, and then increases again as jaw opening approaches maximum opening. In series 2, recordings of bite force maintaining EMG constant show that bite force increases up to a certain range of jaw opening (around 15 to 20 mm) and then decreases as we approach maximum jaw opening. Results show that there is for each experimental subject a physiologically optimum muscular elongation of major efficiency where the masseter develops highest muscular force with least EMG activity.

  14. Bite force and temporomandibular disorder in juvenile chronic arthritis.

    Science.gov (United States)

    Wenneberg, B; Kjellberg, H; Kiliaridis, S

    1995-08-01

    The aim of this study was to investigate the functional condition of the stomatognathic system in children suffering from juvenile chronic arthritis, with respect to bite force and temporomandibular disorder in relation to radiographic abnormalities of the mandibular condyle, occlusal factors and systemic disease parameters. Thirty-five children with juvenile chronic arthritis were compared to 89 healthy children with an Angle Class I occlusion and 62 children with an Angle Class II malocclusion. Subjective symptoms and clinical signs of temporomandibular disorder and radiographic mandibular condylar changes were more common in children with juvenile chronic arthritis than in the two comparison groups. Maximal molar and incisal bite forces and maximal molar bite force endurance times were also significantly reduced in children with juvenile chronic arthritis. It is concluded that the differences between the groups are caused mainly by the systemic inflammatory disease itself, but a functional influence of weakened masticatory muscles cannot be excluded.

  15. 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.

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

    Science.gov (United States)

    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.

  17. Another one bites the dust: bite force and ecology in three caviomorph rodents (Rodentia, Hystricognathi).

    Science.gov (United States)

    Becerra, Federico; Echeverría, Alejandra Isabel; Casinos, Adrià; Vassallo, Aldo Iván

    2014-04-01

    Mammals have developed sophisticated strategies adapting to particular locomotor modes, feeding habits, and social interactions. Many rodent species have acquired a fossorial, semi-fossorial, or even subterranean life-style, converging on morphological, anatomical, and ecological features but diverging in the final arrangement. These ecological variations partially depend on the functional morphology of their digging tools. Muscular and mechanical features (e.g., lever arms relationship) of the bite force were analyzed in three caviomorph rodents with similar body size but different habits and ecological demands of the jaws. In vivo forces were measured at incisors' tip using a strain gauge load cell force transducer whereas theoretical maximal performance values, mechanical advantages, and particular contribution of each adductor muscle were estimated from dissections in specimens of Ctenomys australis (subterranean, solitary), Octodon degus (semi-fossorial, social), and Chinchilla laniger (ground-dweller, colonial). Our results showed that C. australis bites stronger than expected given its small size and C. laniger exhibited the opposite outcome, while O. degus is close to the expected value based on mammalian bite force versus body mass regressions; what might be associated to the chisel-tooth digging behavior and social interactions. Our key finding was that no matter how diverse these rodents' skulls were, no difference was found in the mechanical advantage of the main adductor muscles. Therefore, interspecific differences in the bite force might be primarily due to differences in the muscular development and force, as shown for the subterranean, solitary and territorial C. australis versus the more gracile, ground-dweller, and colonial C. laniger.

  18. 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.

  19. The riddle of the large loss in bite force after fast jaw-closing movements

    NARCIS (Netherlands)

    Slager, GEC; Nagashima, T; van Willigen, JD

    In unloading experiments (in which the resistance to a forceful static bite is suddenly removed); it is shown that the residual bite force (when the jaw system is arrested shortly after the unloading) is remarkably small. For example, of a 100-N initial bite force, only 18 N is left after a jaw

  20. The Jaw Adductor Resultant and Estimated Bite Force in Primates

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    Jonathan M. G. Perry

    2011-01-01

    Full Text Available We reconstructed the jaw adductor resultant in 34 primate species using new data on muscle physiological cross-sectional area (PCSA and data on skull landmarks. Based on predictions by Greaves, the resultant should (1 cross the jaw at 30% of its length, (2 lie directly posterior to the last molar, and (3 incline more anteriorly in primates that need not resist large anteriorly-directed forces. We found that the resultant lies significantly posterior to its predicted location, is significantly posterior to the last molar, and is significantly more anteriorly inclined in folivores than in frugivores. Perhaps primates emphasize avoiding temporomandibular joint distraction and/or wide gapes at the expense of bite force. Our exploration of trends in the data revealed that estimated bite force varies with body mass (but not diet and is significantly greater in strepsirrhines than in anthropoids. This might be related to greater contribution from the balancing-side jaw adductors in anthropoids.

  1. Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli, an ancient apex predator.

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    Anderson, Philip S L; Westneat, Mark W

    2007-02-22

    Placoderms are a diverse group of armoured fishes that dominated the aquatic ecosystems of the Devonian Period, 415-360 million years ago. The bladed jaws of predators such as Dunkleosteus suggest that these animals were the first vertebrates to use rapid mouth opening and a powerful bite to capture and fragment evasive prey items prior to ingestion. Here, we develop a biomechanical model of force and motion during feeding in Dunkleosteus terrelli that reveals a highly kinetic skull driven by a unique four-bar linkage mechanism. The linkage system has a high-speed transmission for jaw opening, producing a rapid expansion phase similar to modern fishes that use suction during prey capture. Jaw closing muscles power an extraordinarily strong bite, with an estimated maximal bite force of over 4400 N at the jaw tip and more than 5300 N at the rear dental plates, for a large individual (6 m in total length). This bite force capability is the greatest of all living or fossil fishes and is among the most powerful bites in animals.

  2. 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.

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

    Science.gov (United States)

    Weihmann, Tom; Reinhardt, Lars; Weißing, Kevin; Siebert, Tobias; Wipfler, Benjamin

    2015-01-01

    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. PMID:26559671

  4. Bite force in patients with functional disturbances of the masticatory system.

    Science.gov (United States)

    Helkimo, E; Carlsson, G E; Carmeli, Y

    1975-10-01

    In thirty patients (24 women and 6 men) treated because of dysfunction of the masticatory system at the department of Stomatognathic Physiology, University of Gothenburg, bite force was registered before, during and after treatment had been completed. In the controls, thirty-six dental students and trainee dental nurses, with no dysfunction of the masticatory system, bite force was registered on two occasions. Bite force was measured between the first molars on each side and between the central incisors. Also finger force was registered. The force measurements were made at five different levels, increasing from very weak to maximum force. Repeated tests of bite force in the control group, made at intervals of about 1 week, gave almost identical results. Bite force in the patient group was lower than in the control group at the first registration but increased with palliation of the symptoms during treatment. There was no significant difference in bite force between the affected and the unaffected side.

  5. Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation.

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    Gregory M Erickson

    Full Text Available BACKGROUND: Crocodilians have dominated predatory niches at the water-land interface for over 85 million years. Like their ancestors, living species show substantial variation in their jaw proportions, dental form and body size. These differences are often assumed to reflect anatomical specialization related to feeding and niche occupation, but quantified data are scant. How these factors relate to biomechanical performance during feeding and their relevance to crocodilian evolutionary success are not known. METHODOLOGY/PRINCIPAL FINDINGS: We measured adult bite forces and tooth pressures in all 23 extant crocodilian species and analyzed the results in ecological and phylogenetic contexts. We demonstrate that these reptiles generate the highest bite forces and tooth pressures known for any living animals. Bite forces strongly correlate with body size, and size changes are a major mechanism of feeding evolution in this group. Jaw shape demonstrates surprisingly little correlation to bite force and pressures. Bite forces can now be predicted in fossil crocodilians using the regression equations generated in this research. CONCLUSIONS/SIGNIFICANCE: Critical to crocodilian long-term success was the evolution of a high bite-force generating musculo-skeletal architecture. Once achieved, the relative force capacities of this system went essentially unmodified throughout subsequent diversification. Rampant changes in body size and concurrent changes in bite force served as a mechanism to allow access to differing prey types and sizes. Further access to the diversity of near-shore prey was gained primarily through changes in tooth pressure via the evolution of dental form and distributions of the teeth within the jaws. Rostral proportions changed substantially throughout crocodilian evolution, but not in correspondence with bite forces. The biomechanical and ecological ramifications of such changes need further examination.

  6. Contribution of the digastric muscles to the control of bite force in man

    NARCIS (Netherlands)

    VanWilligen, JD; Slager, GEC; Broekhuijsen, ML

    1997-01-01

    The contribution of the (co-contracting) digastric muscles to the rapid decline in bite-force magnitude after unloading of a static bite was investigated by asking participants to perform two different biting tasks with sudden unloading, and correlating the degree of co-contraction of the digastrics

  7. Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli, an ancient apex predator

    OpenAIRE

    Anderson, Philip S. L.; Westneat, Mark W

    2006-01-01

    Placoderms are a diverse group of armoured fishes that dominated the aquatic ecosystems of the Devonian Period, 415–360 million years ago. The bladed jaws of predators such as Dunkleosteus suggest that these animals were the first vertebrates to use rapid mouth opening and a powerful bite to capture and fragment evasive prey items prior to ingestion. Here, we develop a biomechanical model of force and motion during feeding in Dunkleosteus terrelli that reveals a highly kinetic skull driven by...

  8. BITE-FORCE ENDURANCE IN PATIENTS WITH TEMPOROMANDIBULAR-JOINT OSTEOARTHROSIS AND INTERNAL DERANGEMENT

    NARCIS (Netherlands)

    STEGENGA, B; BROEKHUIJSEN, ML; DEBONT, LGM; VANWILLIGEN, JD

    1992-01-01

    The aim of this study was to investigate the potential clinical relevance of testing bite force endurance in patients with articular temporomandibular disorders. The endurance of a 50 N bite force was measured in 51 patients with painful temporomandibular joint disorders. The results were compared t

  9. Using sensitivity analysis to validate the predictions of a biomechanical model of bite forces.

    Science.gov (United States)

    Sellers, William Irvin; Crompton, Robin Huw

    2004-02-01

    Biomechanical modelling has become a very popular technique for investigating functional anatomy. Modern computer simulation packages make producing such models straightforward and it is tempting to take the results produced at face value. However the predictions of a simulation are only valid when both the model and the input parameters are accurate and little work has been done to verify this. In this paper a model of the human jaw is produced and a sensitivity analysis is performed to validate the results. The model is built using the ADAMS multibody dynamic simulation package incorporating the major occlusive muscles of mastication (temporalis, masseter, medial and lateral pterygoids) as well as a highly mobile temporomandibular joint. This model is used to predict the peak three-dimensional bite forces at each teeth location, joint reaction forces, and the contributions made by each individual muscle. The results for occlusive bite-force (1080N at M1) match those previously published suggesting the model is valid. The sensitivity analysis was performed by sampling the input parameters from likely ranges and running the simulation many times rather than using single, best estimate values. This analysis shows that the magnitudes of the peak retractive forces on the lower teeth were highly sensitive to the chosen origin (and hence fibre direction) of the temporalis and masseter muscles as well as the laxity of the TMJ. Peak protrusive force was also sensitive to the masseter origin. These result shows that the model is insufficiently complex to estimate these values reliably although the much lower sensitivity values obtained for the bite forces in the other directions and also for the joint reaction forces suggest that these predictions are sound. Without the sensitivity analysis it would not have been possible to identify these weaknesses which strongly supports the use of sensitivity analysis as a validation technique for biomechanical modelling.

  10. Relationship between the training of young recruits and values of bite forces.

    Science.gov (United States)

    Jakovac, Marko; Zivko-Babić, Jasenka; Zdilar, Melita; Kardum-Ivić, Marija

    2012-03-01

    Analysis of masticatory function is the basis of clinical work in almost all fields of dentistry. Bite forces are the expression and measure of masticatory function. Physical training has an effect on the development of functional ability, motoric ability of the organism and the formation of desired physical proportions. The purpose of this study was to examine the association between physical fitness and bite force values. Because of strictly defined regulations in the army with regard to training and nutrition, Croatian Army recruits were ideal examinees for this examination. The examinees were 135 recruits. Bite forces were measured on three places (area of the central incisors, left and right in the area of the first molars) before and after three-months of training. Of all the examinees, 108 had increased their body weight, 12 had decreased it and 15 had not changed their body weight. The median of measured forces in the recruits prior to training was 291 N in the right (lateral quadrant), 285.5 N in the left lateral quadrant and 205 N in the anterior area. After training the median of measured forces in the right quadrant was 312 N, in the left 313 N and in the anterior area 216 N Greater bite forces after training on all measured places were statistically proved. Increased activity of masticatory muscles can have the same effect on the values of bite forces as bite training. There are few data on the correlation between physical muscles and values of bite forces. The results of those studies are doubtful. In this study, after three months of conditional training, the body mass of the recruits had increased and they expressed greater values of bite forces. However, correlation between body mass and bite forces cannot be proved with certainty.

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

    Science.gov (United States)

    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.

  12. A validation study of a new instrument for low cost bite force measurement.

    Science.gov (United States)

    Testa, Marco; Di Marco, Anna; Pertusio, Raffaele; Van Roy, Peter; Cattrysse, Erik; Roatta, Silvestro

    2016-10-01

    Quantitative assessment of force in masticatory muscles is not a routine clinical test, probably due to the lack of an "easy-to-use" device. Aim of this study is (1) to present a low cost bite force instrument located in a custom-made housing, designed to guarantee a comfortable and effective bite action, (2) to evaluate its mechanical characteristics, in order to implement it in clinical settings and in experimental setups. Linearity, repeatability and adaptation over time were assessed on a set of four different sensors in bare and housed condition. Application of the housing to the transducer may appreciably alter the transducer's response. Calibration of the housed transducer is thus necessary in order to correctly record real bite force. This solution may represent a low cost and reliable option for biting force measurement and objective assessment of individual force control in the scientific and clinical setting.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Ontogenetic Scaling of Theoretical Bite Force in Southern Sea Otters (Enhydra lutris nereis).

    Science.gov (United States)

    Law, Chris J; Young, Colleen; Mehta, Rita S

    2016-01-01

    Sexual dimorphism attributed to niche divergence is often linked to differentiation between the sexes in both dietary resources and characters related to feeding and resource procurement. Although recent studies have indicated that southern sea otters (Enhydra lutris nereis) exhibit differences in dietary preferences as well as sexual dimorphism in skull size and shape, whether these intersexual differences translate to differentiation in feeding performances between the sexes remains to be investigated. To test the hypothesis that scaling patterns of bite force, a metric of feeding performance, differ between the sexes, we calculated theoretical bite forces for 55 naturally deceased male and female southern sea otters spanning the size ranges encountered over ontogeny. We then used standardized major axis regressions to simultaneously determine the scaling patterns of theoretical bite forces and skull components across ontogeny and assess whether these scaling patterns differed between the sexes. We found that positive allometric increases in theoretical bite force resulted from positive allometric increases in physiological cross-sectional area for the major jaw adductor muscle and mechanical advantage. Closer examination revealed that allometric increases in temporalis muscle mass and relative allometric decreases in out-lever lengths are driving these patterns. In our analysis of sexual dimorphism, we found that scaling patterns of theoretical bite force and morphological traits do not differ between the sexes. However, adult sea otters differed in their absolute bite forces, revealing that adult males exhibited greater bite forces as a result of their larger sizes. We found intersexual differences in biting ability that provide some support for the niche divergence hypothesis. Continued work in this field may link intersexual differences in feeding functional morphology with foraging ecology to show how niche divergence has the potential to reinforce sexual

  16. The effect of denture stability on bite force and muscular effort.

    Science.gov (United States)

    Caloss, R; Al-Arab, M; Finn, R A; Throckmorton, G S

    2011-06-01

    This study tested the hypothesis that denture instability limits the amount of voluntary muscular effort generated by denture wearers. Seventeen edentulous subjects (seven men, 10 women; mean age 60·3 ± 13·0 years) with newly acquired implant-retained mandibular overdentures and a conventional maxillary denture participated. Maximum bite forces and corresponding electromyographic (EMG) activity from the temporalis and masseter muscles (bilaterally) were recorded under two experimental conditions: (i) Unilateral premolar and molar bites without additional support, and (ii) premolar and molar bites with bite block support on the opposite side. In addition, EMG values alone were recorded during maximum clenching without any transducer between the upper and lower dentures. The level of muscular effort was significantly higher with greater denture support. These results indicate that denture instability probably prevents denture wearers from using the full potential of their jaw muscles, especially during unilateral biting and chewing, even with two implants supporting the mandibular dentures.

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

    DEFF Research Database (Denmark)

    Bakke, Merete; Michler, L; Han, K

    1989-01-01

    Bite force and activity in temporal and masseter muscles during biting and chewing were recorded in 19 control subjects and 23 subjects with symptoms and signs of functional disorders of the craniomandibular system. The entire group comprised 13 men and 29 women, 14-63 yr of age. Maximal unilater...... of mandibular elevator strength as a whole, but inadequate to disclose asymmetric conditions. During isometric contraction, relative strength of electromyographic activity fairly accurately imaged the output of mechanical activity....

  18. INFLUENCE OF VISUAL FEEDBACK ON HUMAN ISOMETRIC BITE-FORCE TREMOR

    NARCIS (Netherlands)

    BROEKHUIJSEN, ML; VANWILLIGEN, JD

    1994-01-01

    In contrast to recent reports, during an isometric short forceful bite, visual feedback had a significant influence on the force tremor spectrum. The value of a 'half-value frequency', being the frequency f1/2 at which, with increasing frequency, the amplitude of the spectrum for the first time drop

  19. INFLUENCE OF VISUAL FEEDBACK ON HUMAN ISOMETRIC BITE-FORCE TREMOR

    NARCIS (Netherlands)

    BROEKHUIJSEN, ML; VANWILLIGEN, JD

    1994-01-01

    In contrast to recent reports, during an isometric short forceful bite, visual feedback had a significant influence on the force tremor spectrum. The value of a 'half-value frequency', being the frequency f1/2 at which, with increasing frequency, the amplitude of the spectrum for the first time drop

  20. Biting

    Science.gov (United States)

    ... 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 ...

  1. Effects of interocclusal distance on bite force and masseter EMG in healthy participants.

    Science.gov (United States)

    Arima, T; Takeuchi, T; Honda, K; Tomonaga, A; Tanosoto, T; Ohata, N; Svensson, P

    2013-12-01

    The aim of this study was to investigate effects of interocclusal distance (IOD) on bite force and masseter electromyographic (EMG) activity during different isometric contraction tasks. Thirty-one healthy participants (14 women and 17 men, 21·2 ± 1·8 years) were recruited. Maximal Voluntary Occlusal Bite Force (MVOBF) between the first molars and masseter EMG activity during all the isometric-biting tasks were measured. The participants were asked to bite at submaximal levels of 20%, 40%, 60% and 80% MVOBF with the use of visual feedback. The thickness of the force transducer was set at 8, 12, 16 and 20 mm (= IOD), and sides were tested in random sequence. MVOBF was significantly higher at 8 mm compared with all other IODs (P EMG (P EMG activity compared with the balancing side (P EMG at any IODs. The results replicated the finding that higher occlusal forces can be generated between the first molars at shorter IODs. The new finding in this study was that an effect of hand dominance could be found on masseter muscle activity during isometric biting. This may suggest that there can be a general dominant side effect on human jaw muscles possibly reflecting differences in motor unit recruitment strategies.

  2. Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci.

    Science.gov (United States)

    Huber, Daniel R; Eason, Thomas G; Hueter, Robert E; Motta, Philip J

    2005-09-01

    Three-dimensional static equilibrium analysis of the forces generated by the jaw musculature of the horn shark Heterodontus francisci was used to theoretically estimate the maximum force distributions and loadings on its jaws and suspensorium during biting. Theoretical maximum bite force was then compared with bite forces measured (1) voluntarily in situ, (2) in restrained animals and (3) during electrical stimulation of the jaw adductor musculature of anesthetized sharks. Maximum theoretical bite force ranged from 128 N at the anteriormost cuspidate teeth to 338 N at the posteriormost molariform teeth. The hyomandibula, which connects the posterior margin of the jaws to the base of the chondrocranium, is loaded in tension during biting. Conversely, the ethmoidal articulation between the palatal region of the upper jaw and the chondrocranium is loaded in compression, even during upper jaw protrusion, because H. francisci's upper jaw does not disarticulate from the chondrocranium during prey capture. Maximum in situ bite force averaged 95 N for free-swimming H. francisci, with a maximum of 133 N. Time to maximum force averaged 322 ms and was significantly longer than time away from maximum force (212 ms). Bite force measurements from restrained individuals (187 N) were significantly greater than those from free-swimming individuals (95 N) but were equivalent to those from both theoretical (128 N) and electrically stimulated measurements (132 N). The mean mass-specific bite of H. francisci was greater than that of many other vertebrates and second highest of the cartilaginous fishes that have been studied. Measuring bite force on restrained sharks appears to be the best indicator of maximum bite force. The large bite forces and robust molariform dentition of H. francisci correspond to its consumption of hard prey.

  3. The effects of stretching exercise for upper trapezius on the asymmetric rate of bite force.

    Science.gov (United States)

    Lee, Bomjin; Lee, Joongsook; Yang, Jeongok; Heo, Kwangjin; Hwang, Hojin; Kim, Boyoung; Han, Dongwook

    2015-07-01

    [Purpose] The purpose of this study was to observe the effects of stretching the upper trapezius muscle on the asymmetric rate of bite force. [Subjects] Forty-seven female university students who had all their original teeth, had no disorders in the temporomandibular joints, and had never worn braces; participated in this study. [Methods] An occlusometer was used to measure biting forces. Subsequently, stretching exercises of the upper trapezius were performed. The subjects were divided into 3 groups at the start of the testing: the asymmetric rate of the first group was less than 10%; the asymmetric rate of the second group was between 10% and 20%; and the asymmetric rate of the third group was more than 20%. The stretching exercises were done on the dominant side of the upper trapezius. [Results] After the stretching exercises of the upper trapezius, the results showed that for the first group, whose asymmetric rate of biting force was less than 10%, there was a significant increase in asymmetric rate (from 5.1% to 10.3%). For the second group, whose asymmetric rate of biting force was measured to be between 10% and 20%, the asymmetric rate decreased from 14.7% to 14.3%, but the change was not statistically significant. For the third group, whose asymmetric rate of biting force was more than 20%, there was a significant decrease in asymmetric rate (from 27.8% to 12.6%). [Conclusion] We concluded that stretching exercises of the upper trapezius muscle had a direct effect on the asymmetric rate of biting force.

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

    Directory of Open Access Journals (Sweden)

    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. The effect of a new denture adhesive on bite force until denture dislodgement

    NARCIS (Netherlands)

    Ozcan, M.; Kulak, Y.; de Baat, C.; Arikan, A.; Ucankale, M.

    2005-01-01

    : PURPOSE: Denture adhesives are used to improve the denture retention and comfort of complete denture wearers. The purpose of this investigation was to establish the effect of a new denture adhesive on maximum bite force until denture dislodgement (BFDD) after adhesive application. MATERIALS AND

  6. The effect of a new denture adhesive on bite force until denture dislodgement

    NARCIS (Netherlands)

    B. Özcan (Behiye); Y. Kulak (Yasemin); C. de Baat; A. Arikan (Ayla); M. Ucankale (Mert)

    2005-01-01

    textabstractPurpose: Denture adhesives are used to improve the denture retention and comfort of complete denture wearers. The purpose of this investigation was to establish the effect of a new denture adhesive on maximum bite force until denture dislodgement (BFDD) after adhesive application.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    DEFF Research Database (Denmark)

    Andersen, Malene Krogh; Sonnesen, Ane Liselotte

    2013-01-01

    The aim was to analyse which parameters in a standard orthodontic material are most important for identifying factors for low bite force. Such analyses have not previously been reported in adult orthodontic patients. The sample comprised 95 adults (67 females and 28 males) aged 18-55 years sequen...... angle are at risk of having low bite force. This may prove valuable in the clinic, especially in orthodontic cases with an increased need for vertical anchorage during treatment.......The aim was to analyse which parameters in a standard orthodontic material are most important for identifying factors for low bite force. Such analyses have not previously been reported in adult orthodontic patients. The sample comprised 95 adults (67 females and 28 males) aged 18-55 years...... sequentially admitted for conventional orthodontic treatment. All subjects had moderate to severe malocclusions. Bite force was measured by a pressure transducer, craniofacial dimensions and head posture were measured on profile radiographs, number of teeth in contact were evaluated with a plastic strip...

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Acoustic myography, electromyography and bite force in the masseter muscle.

    Science.gov (United States)

    Tortopidis, D; Lyons, M F; Baxendale, R H

    1998-12-01

    Acoustic myography (AMG) offers some advantages over electromyography (EMG) in certain circumstances, but the use of AMG on the jaw-closing muscles has not been fully tested. The purpose of this study was to examine the relationship between AMG, EMG and force in the masseter muscles of nine healthy male subjects. The AMG was recorded using a piezoelectric crystal microphone and the EMG was recorded simultaneously with surface electrodes. Force was recorded between the anterior teeth with a strain-gauge transducer. Analysis showed that Pearson's correlation coefficient was 0.913 for force/AMG and 0.973 for force/EMG in all subjects, indicating a linear relationship between force, AMG and EMG at the four different force levels tested (25-75% of maximum). It is apparent that AMG may be used as an accurate monitor of masseter muscle force production, although some care is required in the technique.

  12. Visual Feedback of Bilateral Bite Force to Assess Motor Control of the Mandible in Isometric Condition.

    Science.gov (United States)

    Testa, Marco; Geri, Tommaso; Signori, Alessio; Roatta, Silvestro

    2015-10-01

    The assessment of the individual ability of modulating and coordinating the right and left bite force is poorly investigated. The present study describes a methodology for the assessment of the bilateral control of the biting force and evaluates the test-retest reliability in a sample of 13 healthy subjects. By modulating the intensity and the left/right balance of the biting force, the subject was able to drive a cursor on the screen to "reach and hold" targets, randomly generated within the physiological "range of force" of the subject. The average motor performance was evaluated by the mean cursor-target distance = 13 ± 5%, the Offset Error = 9 ± 5% and the standard deviation of the force vector = 17.7 ± 6.1% (expressed as % of the target). Mean distance and standard deviation indices had acceptable reliability. This technique improves the characterization of the mandibular motor function and it may have a relevant role for the assessment and rehabilitation of the neuromusculoskeletal disorders affecting the orofacial system.

  13. Novel system for bite-force sensing and monitoring based on magnetic near field communication.

    Science.gov (United States)

    Lantada, Andres Diaz; Bris, Carlos González; Morgado, Pilar Lafont; Maudes, Jesús Sanz

    2012-01-01

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Lantada, Andres Diaz; Bris, Carlos González; Morgado, Pilar Lafont; Maudes, Jesús Sanz

    2012-01-01

    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. PMID:23112669

  16. Improving masticatory performance, bite force, nutritional state and patient's satisfaction with implant overdentures: a systematic review of the literature.

    Science.gov (United States)

    Boven, G C; Raghoebar, G M; Vissink, A; Meijer, H J A

    2015-03-01

    Oral function with removable dentures is improved when dental implants are used for support. A variety of methods is used to measure change in masticatory performance, bite force, patient's satisfaction and nutritional state. A systematic review describing the outcome of the various methods to assess patients' appreciation has not been reported. The objective is to systematically review the literature on the possible methods to measure change in masticatory performance, bite force, patient's satisfaction and nutritional state of patients with removable dentures and to describe the outcome of these. Medline, Embase and The Cochrane Central Register of Controlled Trials were searched (last search July 1, 2014). The search was completed by hand to identify eligible studies. Two reviewers independently assessed the articles. Articles should be written in English. Study design should be prospective. The outcome should be any assessment of function/satisfaction before and at least 1 year after treatment. Study population should consist of fully edentulous subjects. Treatment should be placement of any kind of root-form implant(s) to support a mandibular and/or maxillary overdenture. Fifty-three of 920 found articles fulfilled the inclusion criteria. A variety of methods was used to measure oral function; mostly follow-up was 1 year. Most studies included mandibular overdentures, three studies included maxillary overdentures. Implant-supported dentures were accompanied by high patient's satisfaction with regard to denture comfort, but this high satisfaction was not always accompanied by improvement in general quality of life (QoL) and/or health-related QoL. Bite force improved, masseter thickness increased and muscle activity in rest decreased. Patients could chew better and eat more tough foods. No changes were seen in dietary intake, BMI and blood markers. Improvements reported after 1 year apparently decreased slightly with time, at least on the long run. Treating

  17. Connecting behaviour and performance: the evolution of biting behaviour and bite performance in bats.

    Science.gov (United States)

    Santana, S E; Dumont, E R

    2009-11-01

    Variation in behaviour, performance and ecology are traditionally associated with variation in morphology. A neglected part of this ecomorphological paradigm is the interaction between behaviour and performance, the ability to carry out tasks that impact fitness. Here we investigate the relationship between biting behaviour and performance (bite force) among 20 species of ecologically diverse bats. We studied the patterns of evolution of plasticity in biting behaviour and bite force, and reconstructed ancestral states for behaviour and its plasticity. Both behavioural and performance plasticity exhibited accelerating evolution over time, and periods of rapid evolution coincided with major dietary shifts from insect-feeding to plant-feeding. We found a significant, positive correlation between behavioural plasticity and bite force. Bats modulated their performance by changing their biting behaviour to maximize bite force when feeding on hard foods. The ancestor of phyllostomids was likely a generalist characterized by high behavioural plasticity, a condition that also evolved in specialized frugivores and potentially contributed to their diversification.

  18. Krait bite requiring high dose antivenom: a case report.

    Science.gov (United States)

    Sharma, Sanjib Kumar; Koirala, Shekhar; Dahal, Gaheraj

    2002-03-01

    Anti snake venom (ASV) is the most specific therapy available for treatment of snakebite envenomation. The ASV available in Nepal are polyvalent ASV produced in India and are effective against envenomation by cobra and krait, the two most common species found in Eastern Nepal. Neurotoxic signs respond slowly and unconvincingly and continuous absorption of venom may cause recurrent neurotoxicity. Therefore, close observation and continuous administration of ASV is essential to save the victim. We report a case of neurotoxic envenomation due to bite by common krait (Bangarus caeruleus). The victim required very high dose of polyvalent ASV for reversal of neurological manifestations.

  19. Jaw myology and bite force of the monk parakeet (Aves, Psittaciformes).

    Science.gov (United States)

    Carril, Julieta; Degrange, Federico J; Tambussi, Claudia P

    2015-07-01

    Psittaciform birds exhibit novelties in jaw bone structure and musculature that are associated with strong bite forces. These features include an ossified arcus suborbitalis and the muscles ethmomandibularis and pseudomasseter. We analyse the jaw musculature of the monk parakeet (Myiopsitta monachus) to enable future studies aimed at understanding craniofacial development, morphology, function and evolution. We estimate bite force based on muscle dissections, physiological cross-sectional area and skull biomechanical modelling. We also compare our results with available data for other birds and traced the evolutionary origin of the three novel diagnostic traits. Our results indicate that, in Myiopsitta, (i) the arcus suborbitalis is absent and the orbit is ventrally closed by an elongate processus orbitalis and a short ligamentum suborbitale; (ii) the ethmomandibularis muscle is a conspicuous muscle with two bellies, with its origin on the anterior portion of the septum interorbitale and insertion on the medial aspect of the mandible; (iii) the pseudomasseter muscle consists of some fibers arising from the m. adductor mandibulae externus superficialis, covering the lateral surface of the arcus jugalis and attaches by an aponeurotic sheet on the processus orbitalis; (iv) a well-developed adductor mandibulae complex is present; (v) the bite force estimation relative to body mass is higher than that calculated for other non-psittaciform species; and (vi) character evolution analysis revealed that the absence of the arcus suborbitalis and the presence of the m. pseudomassseter are the ancestral conditions, and mapping is inconclusive about presence of one or two bellies of the m. ethmomandibularis. © 2015 Anatomical Society.

  20. Jaw myology and bite force of the monk parakeet (Aves, Psittaciformes)

    Science.gov (United States)

    Carril, Julieta; Degrange, Federico J; Tambussi, Claudia P

    2015-01-01

    Psittaciform birds exhibit novelties in jaw bone structure and musculature that are associated with strong bite forces. These features include an ossified arcus suborbitalis and the muscles ethmomandibularis and pseudomasseter. We analyse the jaw musculature of the monk parakeet (Myiopsitta monachus) to enable future studies aimed at understanding craniofacial development, morphology, function and evolution. We estimate bite force based on muscle dissections, physiological cross-sectional area and skull biomechanical modelling. We also compare our results with available data for other birds and traced the evolutionary origin of the three novel diagnostic traits. Our results indicate that, in Myiopsitta, (i) the arcus suborbitalis is absent and the orbit is ventrally closed by an elongate processus orbitalis and a short ligamentum suborbitale; (ii) the ethmomandibularis muscle is a conspicuous muscle with two bellies, with its origin on the anterior portion of the septum interorbitale and insertion on the medial aspect of the mandible; (iii) the pseudomasseter muscle consists of some fibers arising from the m. adductor mandibulae externus superficialis, covering the lateral surface of the arcus jugalis and attaches by an aponeurotic sheet on the processus orbitalis; (iv) a well-developed adductor mandibulae complex is present; (v) the bite force estimation relative to body mass is higher than that calculated for other non-psittaciform species; and (vi) character evolution analysis revealed that the absence of the arcus suborbitalis and the presence of the m. pseudomassseter are the ancestral conditions, and mapping is inconclusive about presence of one or two bellies of the m. ethmomandibularis. PMID:26053435

  1. 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 age...... in subjects having concave facial profile when compared to convex (P = 0.045) and straight (P = 0.039) facial profile. BMI and arch form showed no significant relationship with MMBF. CONCLUSION: The MMBF is found to be affected by gender and some of the anthropometric features like facial form and palatal...

  2. 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.

  3. Evaluation of Treatments in Patients with Nocturnal Bruxism on Bite Force and Occlusal Contact Area: A preliminary report

    Science.gov (United States)

    Alkan, Alper; Bulut, Emel; Arici, Selim; Sato, Shuichi

    2008-01-01

    Objectives The purpose of this study was to investigate the short-term effects of occlusal splint therapy and tricyclic antidepressants on the bite force and occlusal contact area of patients presenting with nocturnal bruxism. Methods A maxillary full-coverage hard acrylic splint was applied to the five patients (Group S). Five patients took a tricyclic antidepressant (Amitriptiline HCl, 10 mg/day) for 3 months (Group A) and a control group (Group C) comprising of 10 dental school students with normal occlusion was also formed. Using a Dental Prescale (Fuji Photo Film Corporation, Tokyo, Japan) and an Occluzer computer (FPD703, Fuji Photo Film Corporation, Tokyo, Japan) the bite force and occlusal contact area were measured. The evaluations were made just before the treatment and at 1 month and 3 months of treatment. Results The bite force and occlusal contact area before treatment in study Groups A and S were found to be higher than those in the Group C. Furthermore, the bite force and occlusal contact area increased during treatment in Group A whilst they decreased in Group S. Bite force and occlusal contact area in Group S were lower at both 1 month and 3 months of treatment than in Group C. Conclusions It could be tentatively suggested that occlusal splint therapy may be more effective than tricyclic antidepressant in the treatment of bruxism. Further investigations of this measurement method involving larger study populations and a longer follow-up period are needed. PMID:19212534

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Cranial biomechanics, bite force and function of the endocranial sinuses in Diprotodon optatum, the largest known marsupial.

    Science.gov (United States)

    Sharp, Alana C; Rich, Thomas H

    2016-06-01

    The giant extinct marsupial Diprotodon optatum has unusual skull morphology for an animal of its size, consisting of very thin bone and large cranial sinuses that occupy most of the internal cranial space. The function of these sinuses is unknown as there are no living marsupial analogues. The finite element method was applied to identify areas of high and low stress, and estimate the bite force of Diprotodon to test hypotheses on the function of the extensive cranial sinuses. Detailed three-dimensional models of the cranium, mandible and jaw adductor muscles were produced. In addition, manipulations to the Diprotodon cranial model were performed to investigate changes in skull and sinus structure, including a model with no sinuses (sinuses 'filled' with bone) and a model with a midsagittal crest. Results indicate that the cranial sinuses in Diprotodon significantly lighten the skull while still providing structural support, a high bite force and low stress, indicating the cranium may have been able to withstand higher loads than those generated during feeding. Data from this study support the hypothesis that pneumatisation is driven by biomechanical loads and occurs in areas of low stress. The presence of sinuses is likely to be a byproduct of the separation of the outer surface of the skull from the braincase due to the demands of soft tissue including the brain and the large jaw adductor musculature, especially the temporalis. In very large species, such as Diprotodon, this separation is more pronounced, resulting in extensive cranial sinuses due to a relatively small brain compared with the size of the skull.

  6. High Current Density Effect on In-situ Atomic Migration Characteristics of a BiTe Thin Film System

    Science.gov (United States)

    Kim, Seunghyun; Park, Yong-Jin; Joo, Young-Chang; Park, Young-Bae

    2013-10-01

    Understanding fundamental atomic migration characteristics of multicomponent chalcogenide materials such as GeSbTe (GST) and BiTe are important in order to investigate the failure mechanism related to the electrical reliability of thermoelectric materials under high current density. In this work, high current density effect on the in-situ atomic migration characteristics of the BiTe thermoelectric thin films was conducted by real-time observation inside an scanning electron microscope chamber. Under the high current density conditions ranging from 0.83×106 to 1.0×106 A/cm2 at 100 °C, Te migrated toward the cathode, and Bi migrated toward the anode because the electrostatic force was dominant by very high Joule heating effect.

  7. Is extreme bite performance associated with extreme morphologies in sharks?

    Science.gov (United States)

    Huber, Daniel R; Claes, Julien M; Mallefet, Jérôme; Herrel, Anthony

    2009-01-01

    As top predators in many oceanic communities, sharks are known to eat large prey and are supposedly able to generate high bite forces. This notion has, however, largely gone untested due to the experimental intractability of these animals. For those species that have been investigated, it remains unclear whether their high bite forces are simply a consequence of their large body size or the result of diet-related adaptation. As aquatic poikilotherms, sharks can grow very large, making them ideal subjects with which to investigate the effects of body size on bite force. Relative bite-force capacity is often associated with changes in head shape because taller or wider heads can, for example, accommodate larger jaw muscles. Constraints on bite force in general may also be released by changes in tooth shape. For example, more pointed teeth may allow a predator to penetrate prey more effectively than blunt, pavementlike teeth. Our analyses show that large sharks do not bite hard for their body size, but they generally have larger heads. Head width is the best predictor of bite force across the species included in our study as indicated by a multiple regression model. Contrary to our predictions, sharks with relatively high bite forces for their body size also have relatively more pointed teeth at the front of the tooth row. Moreover, species including hard prey in their diet are characterized by high bite forces and narrow and pointed teeth at the jaw symphysis.

  8. Bite force and feeding kinematics in the eastern North Pacific Kyphosidae.

    Science.gov (United States)

    Moran, Clinton Joseph; Ferry, Lara

    2014-04-01

    Some fishes that feed on attached food items possess an intramandibular joint (IMJ), which is thought to increase maximum gape and facilitate contact between the tooth-bearing surface and the substrate. However, the mechanical consequences of using an IMJ to remove attached food items from the substrate are still poorly understood. We examined the most prominent eastern North Pacific kyphosid, the scraper: Girella nigricans and two other kyphosids, Medialuna californiensis and Hermosilla azurea, which occupy similar habitats. Of the three species, G. nigricans had the highest theoretical bite force per unit length. We examined the feeding mechanics of G. nigricans in two different feeding scenarios: a scraping behavior elicited on a block of brine shrimp gelatin and a picking behavior elicited on Ulva sp. We measured cranial elevation, lower jaw rotation, premaxillary protrusion, premaxillary rotation, gape maximum, and intramandibular rotation. Ulva treatments produced significantly greater cranial rotation, when compared to gelatin treatments. Gelatin treatments were associated with greater lower jaw rotation and larger gape. Premaxillary rotation and premaxillary protrusion did not differ between treatments. Intramandibular rotation occurred only when G. nigricans physically contacted the gelatin, suggesting the IMJ is a passive joint with no associated musculature. We also noted that G. nigricans do not appear to use suction to draw food into the mouth. The lack of suction and the presence of the IMJ suggest that the jaws of G. nigricans are specialized for maximizing jaw force when scraping.

  9. Maximum occlusal bite forces in Jordanian individuals with different dentofacial vertical skeletal patterns.

    Science.gov (United States)

    Abu Alhaija, Elham S J; Al Zo'ubi, Ibraheem A; Al Rousan, Mohammed E; Hammad, Mohammad M

    2010-02-01

    This study was carried out to record maximum occlusal bite force (MBF) in Jordanian students with three different facial types: short, average, and long, and to determine the effect of gender, type of functional occlusion, and the presence of premature contacts and parafunctional habits on MBF. Sixty dental students (30 males and 30 females) were divided into three equal groups based on the maxillomandibular planes angle (Max/Mand) and degree of anterior overlap: included short-faced students with a deep anterior overbite (Max/Mand or = 32 degrees). Their age ranged between 20 and 23 years. MBF was measured using a hydraulic occlusal force gauge. Occlusal factors, including the type of functional occlusion, the presence of premature contacts, and parafunctional habits, were recorded. Differences between groups were assessed using a t-test and analysis of variance. The average MBF in Jordanian adults was 573.42 +/- 140.18 N. Those with a short face had the highest MBF (679.60 +/- 117.46 N) while the long-face types had the lowest MBF (453.57 +/- 98.30 N; P < 0.001). The average MBF was 599.02 +/- 145.91 in males and 546.97 +/- 131.18 in females (P = 0.149). No gender differences were observed. The average MBF was higher in patients with premature contacts than those without, while it did not differ in subjects with different types of functional occlusion or in the presence of parafunctional habits.

  10. Craniofacial Morphology Affects Bite Force in Patients with Painful Temporomandibular Disorders.

    Science.gov (United States)

    Bavia, Paula Furlan; Vilanova, Larissa Soares Reis; Garcia, Renata Cunha Matheus Rodrigues

    2016-01-01

    Craniofacial morphology affects masticatory performance in healthy dentate subjects, but little is known about its effects in patients with painful temporomandibular disorders (TMDs). Forty-eight female patients (mean age of 28±5.8 years) with painful TMDs underwent lateral cephalometric radiography. Using Ricketts' cephalometric analysis and the Vert method, subjects were assigned to three groups according to their craniofacial morphology: brachyfacial (n=22), mesofacial (n=13), and dolichofacial (n=13). Research diagnostic criteria for TMD were used to confirm the TMD diagnosis for each patient. Pain intensity was reported by each patient based on a visual analog scale (VAS). Maximum bite force (MBF) was measured with pressure sensors placed on the first molar site. Masticatory performance (MP) was assessed by chewing a silicone-based artificial material and determining the resulting particle size by the sieve method. Chewing ability (CA) was evaluated for seven food types and analyzed by a VAS questionnaire. Data were analyzed by one-way ANOVA followed by a Tukey-Kramer test (pcraniofacial morphology affects the MBF without impairing MP or CA in patients with painful TMDs.

  11. Infliximab partially alleviates the bite force reduction in a mouse model of temporomandibular joint pain.

    Science.gov (United States)

    Kim, Sang-Hyon; Son, Chang-Nam; Lee, Hyo-Jung; Cho, Ho-Chan; Jung, Sung-Won; Hur, Ji An; Baek, Won-Ki; Jung, Hye Ra; Hong, Ji Hee

    2015-05-01

    Temporomandibular joint (TMJ) disorder is clinically important because of its prevalence, chronicity, and therapy-refractoriness of the pain. In this study, we investigated the effect of infliximab in a mouse model of TMJ pain using a specially-engineered transducer for evaluating the changes in bite force (BF). The mice were randomly divided into three groups (7 mice per group): the control group, the complete Freund's adjuvant (CFA) group, and the infliximab group. BF was measured at day 0 (baseline BF). After measuring the baseline BF, CFA or incomplete Freund's adjuvant was injected into both TMJs and then the changes in BF were measured at days 1, 3, 5, 7, 9, and 13 after the TMJ injection. For measuring the BF, we used a custom-built BF transducer. Control, CFA, and infliximab groups showed similar baseline BF at day 0. From day 1, a significant reduction in BF was observed in the CFA group, and this reduction in BF was statistically significant compared to that in the control group (P infliximab group also, the reduction in BF was observed on day 1, and this reduction was maintained until day 7. However, the degree of reduction in BF was less remarkable compared to that in the CFA group. The reduction in BF caused by injection of CFA into the TMJ could be partially alleviated by the injection of anti-tumor necrosis factor alpha, infliximab.

  12. 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.

  13. EMG activities of two heads of the human lateral pterygoid muscle in relation to mandibular condyle movement and biting force.

    Science.gov (United States)

    Hiraba, K; Hibino, K; Hiranuma, K; Negoro, T

    2000-04-01

    Electromyographic (EMG) activities of the superior (SUP) and inferior heads (INF) of the lateral pterygoid muscle (LPT) were recorded in humans during voluntary stepwise changes in biting force and jaw position that were adopted to exclude the effects of acceleration and velocity of jaw movements on the muscle activity. The SUP behaved like a jaw-closing muscle and showed characteristic activity in relation to the biting force. It showed a considerable amount of background activity (5-32% of the maximum) even in the intercuspal position without teeth clenching and reached a nearly maximum activity at relatively lower biting-force levels than the jaw-closing muscles during increment of the biting force. Stretch reflexes were found in the SUP, the function of which could be to stabilize the condyle against the biting force that pulls the condyle posteriorly. This notion was verified by examining the biomechanics on the temporomandibular joint. The complex movements of the mandibular condyle in a sagittal plane were decomposed into displacement in the anteroposterior direction (Ac) and angle of rotation (RAc) around a kinesiological specific point on the condyle. In relation to Ac, each head of the LPT showed quite a similar behavior to each other in all types of jaw movements across all subjects. Working ranges of the muscle activities were almost constant (Ac 3 mm for the INF). The amount of EMG activity of the SUP changed in inverse proportion to Ac showing a hyperbola-like relation, whereas that of the INF changed rather linearly. The EMG amplitude of the SUP showed a quasilinear inverse relation with RAc in the hinge movement during which the condyle rotated with no movement in the anteroposterior direction. This finding suggests that the SUP controls the angular relationship between the articular disk and the condyle. On the other hand, the position of the disk in relation to the maxilla, not to the condyle, is controlled indirectly by the INF because the disk

  14. Lizard Bites

    Science.gov (United States)

    ... Mite Bites Mollusk Stings Puss Moth Caterpillar Stings Scorpion Stings Sea Urchin Stings Snakebites Spider Bites Stingray ... Mite Bites Mollusk Stings Puss Moth Caterpillar Stings Scorpion Stings Sea Urchin Stings Snakebites Spider Bites Stingray ...

  15. Bite force in the extant coelacanth Latimeria: the role of the intracranial joint and the basicranial muscle.

    Science.gov (United States)

    Dutel, Hugo; Herbin, Marc; Clément, Gaël; Herrel, Anthony

    2015-05-01

    The terrestrialization process involved dramatic changes in the cranial anatomy of vertebrates. The braincase, which was initially divided into two portions by the intracranial joint in sarcopterygian fishes, became consolidated into a single unit in tetrapods and lungfishes [1-3]. The coelacanth Latimeria is the only extant vertebrate that retains an intracranial joint, which is associated with a unique paired muscle: the basicranial muscle. The intracranial joint has long been thought to be involved in suction feeding by allowing an extensive elevation of the anterior portion of the skull, followed by its rapid depression driven by the basicranial muscle [4-7]. However, we recently challenged this hypothesis [8, 9], and the role of the basicranial muscle with respect to the intracranial joint thus remains unclear. Using 3D biomechanical modeling, we show here that the basicranial muscle and the intracranial joint are involved in biting force generation. By flexing the anterior portion of the skull at the level of the intracranial joint, the basicranial muscle increases the overall bite force. This likely allows Latimeria to feed on a broad range of preys [10, 11] and coelacanths to colonize a wide range of environments during their evolution [4]. The variation in the morphology of the intracranial joint observed in Devonian lobe-finned fishes would have impacted to various degrees their biting performance and might have permitted feeding specializations despite the stability in their lower jaw morphology [12]. VIDEO ABSTRACT.

  16. Bite force of children with repaired unilateral and bilateral cleft lip and palate.

    Science.gov (United States)

    Garcia, Michele Alves; Rios, Daniela; Honório, Heitor Marques; Trindade-Suedam, Ivy Kiemle

    2016-08-01

    To assess the bite force (BF) of children with repaired cleft lip and palate (CLP). Children aged 6-12 years, with and without CLP, were divided into the following 5 groups: (1) control group (CON): 34 children without CLP (17 female, 17 male, mean age 8.2±1.4); (2) cleft lip group (CL): 31 children with cleft lip involving the pre-maxilla (15 female, 16 male, mean age 9.7±1.3); (3) unilateral CLP group (UCLP): 36 children with complete unilateral CLP (11 female, 25 male, mean age 9.4±1.6); (4) bilateral CLP group (BCLP): 32 children with complete bilateral CLP (11 female, 21 male, mean age 9.5±1.7); and 5) cleft palate group (CP): 17 children with complete cleft palate (9 female, 8 male, mean age 9.4±1.6). Briefly, in this clinical trial, BF was assessed before alveolar bone grafting with a gnathodynamometer (IDDK, Kratos, Cotia, SP, Brazil). For CON, BCLP, CL and CP groups, BF was obtained in the anterior and posterior region of the maxilla. For the UCLP group, BF was assessed in the anterior and posterior regions of both segments. Differences among groups were evaluated by ANOVA test, and Tukey's test was used to assess any correlations among variables (Pcleft groups. However, a stronger BF was observed in the CL group when compared to the UCLP and BCLP groups. Next, no differences were observed between the cleft side and the noncleft side in the UCLP group. Lastly, in all groups, BFs from the anterior region of the maxilla were less when compared to the posterior regions. The BF of children with CLP is no different from children without CLP. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Changes in biting forces with implant-supported overdenture in the lower jaw: A comparison between conventional and mini implants in a pilot study.

    Science.gov (United States)

    Hasan, I; Madarlis, C; Keilig, L; Dirk, C; Weber, A; Bourauel, C; Heinemann, F

    2016-11-01

    The biting ability of patients improves noticeably after receiving implant-supported overdentures in comparison to conventional complete dentures. However, the change of biting with such treatment concepts has been quantitatively investigated in only a limited number of studies. The aim of the present study has been to measure the biting forces of edentulous patients with complete dentures and after receiving implant-supported overdentures. A total of 26 edentulous patients were included. Ten patients received two to four conventional implants (control group, Ø3.3-3.7mm, L11-13mm) and 16 patients received four to five mini implants (study group, Ø1.8-2.4mm, L13-15mm) inserted in the mandibular interforaminal region. All patients received a lower overdenture with ball/rubber ring attachments and a complete denture for the maxilla. The biting forces were measured using Prescale pressure sheets type low before the insertion of implants and after receiving implant-supported overdenture. The measured sheets were later scanned and analysed using FPD-8010E software. The range of biting forces before the insertion of implants was 80N-122N for the control group and 66-88N for the study group. After the insertion of implants, the range of biting forces increased to 167N-235N for the control group and to 81N-138N for the study group. However, the increase in biting forces after the insertion of implants was not significant for either group. No significant difference was obtained between the two implant systems. The biting forces improved after insertion of implants regardless of which implant system was used. However, the degree of improvement is noticeably related to the original bone quality of the mandible at the insertion regions of implants.

  18. 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.

  19. Effect of experimental jaw muscle pain on EMG activity and bite force distribution at different level of clenching.

    Science.gov (United States)

    Shimada, A; Hara, S; Svensson, P

    2013-11-01

    Bite force at different levels of clenching and the corresponding electromyographic (EMG) activity in jaw-closing muscles were recorded in 16 healthy women before, during and after painful stimulation of the left masseter muscle. Experimental pain was induced by infusion of 5·8% hypertonic saline (HS), and 0·9% isotonic saline (IS) was infused as a control. EMG activity was recorded bilaterally from the masseter and temporalis muscles, and static bite force was assessed by pressure-sensitive films (Dental Pre-scale) at 5, 50 and 100% of maximal voluntary contraction (MVC) during each session. Visual feedback was applied by showing EMG activity to help the subject perform clenching at 5, 50 and 100% MVC, respectively. EMG activity at 100% MVC in left and right masseter decreased significantly during painful HS infusion (1·7-44·6%; P MVC was decreased during HS infusion in the painful masseter muscle (4·8-18·6%; P MVC during HS infusion and in the post-infusion condition (P MVC. In conclusion, experimental pain in the masseter muscle has an inhibitory effect on jaw muscle activity at maximal voluntary contraction, and compensatory mechanisms may influence the recruitment pattern at submaximal efforts.

  20. Snake bites

    Science.gov (United States)

    Bites - snakes ... Snake bites can be deadly if not treated quickly. Because of their smaller body size, children are ... risk for death or serious complications due to snake bites. The right antivenom can save a person's ...

  1. Animal Bites

    Science.gov (United States)

    ... or territory. Attacks by pets are more common. Animal bites rarely are life-threatening, but if they become infected, you can develop serious medical problems. To prevent animal bites and complications from bites Never pet, handle, ...

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Mosquito Bites

    Science.gov (United States)

    ... larvae, then pupae, and then they become adult mosquitos. The males live for about a week to ... can live for months. What health problems can mosquito bites cause? Most mosquito bites are harmless, but ...

  4. Jaw muscle size and bite force magnitude in relation to craniofacial morphology

    NARCIS (Netherlands)

    Raadsheer, M.C.

    1999-01-01

    In this thesis it is shown for the first time that jaw muscle size and craniofacial morphology are already significantly related during growth. This supports the assumption that the tensile forces of the muscles of mastication are a growth regulating factor in craniofacial morphogenesis. In the

  5. Nonsurgical treatment of adult open bite using edgewise appliance combined with high-pull headgear and class III elastics.

    Science.gov (United States)

    Saito, Isao; Yamaki, Masaki; Hanada, Kooji

    2005-03-01

    This case report describes the effect of a combination of high-pull headgear and Class III elastics on the nonsurgical treatment of an adult open bite. The 19-year 1-month-old Japanese female presented with the anterior open bite of 4.0 mm and mild crowding. She had a skeletal Class II but a Class III molar relationship due to a severe proclination of the mandibular dental arch. Unilateral congenital missing premolars caused a discrepancy between the facial and dental midline. After extraction of two premolars and the impacted mandibular third molars, nonsurgical therapy was performed using the standard edgewise appliance combined with a high-pull headgear and Class III elastics. The successful treatment outcome and stability of the final occlusion indicates that a combination of high-pull headgear and Class III elastics is one of the effective devices in the nonsurgical treatment of open bite and, is especially helpful in uprighting the mandibular dental arch.

  6. [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.

  7. 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

    1997-01-01

    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

  8. Bug Bites and Stings

    Science.gov (United States)

    ... and Wasp Stings Flea and Tick Bites Mosquito Bites Spider Bites What to Do Serious Stuff — Get Medical ... diseases, such as malaria and dengue fever. Spider Bites Most spider bites are minor, although they can cause mild ...

  9. Stork bite

    Science.gov (United States)

    ... newborns. A stork bite is due to a stretching (dilation) of certain blood vessels. It may become ... all birthmarks during a routine well-baby exam . Prevention There is no known prevention. Alternative Names Salmon ...

  10. Tick Bites

    Science.gov (United States)

    ... that go outdoors, you need to beware of ticks. Ticks are small bloodsucking parasites. Many species transmit diseases ... of the diseases you can get from a tick bite are Lyme disease, ehrlichiosis, Rocky Mountain spotted ...

  11. Animal Bites

    Science.gov (United States)

    ... to 15 to 20 of every 100 following dog or human bites. Treatment If your child is bleeding from ... dangerous than those from tame, immunized (against rabies) dogs and cats. The health of the animal also is important, so if ...

  12. 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.

  13. Simulation of a flow around biting teeth

    Science.gov (United States)

    Narusawa, Hideaki; Yamamoto, Eriko; Kuwahara, Kunio

    2008-11-01

    We simulated a flow around biting teeth. The decayed tooth is a disease that a majority of people are annoyed. These are often generated from a deep groove at occlusal surface. It is known that a person who bites well doesn't suffer from a decayed tooth easily. Biting forces reach as much as 60 kg/cm^2 by an adult male, and when chewing, upper and lower teeth approach to bite by those forces. The crushed food mixed with saliva becomes high viscosity fluid, and is pushed out of ditches of teeth in the direction of the cheek or the tongue. Teeth with complex three dimension curved surface are thought to form venturi at this time, and to generate big pressure partially. An excellent dental articulation will possibly help a natural generation of a flow to remove dental plaque, i.e. the cause of the decayed tooth. Moreover, the relation of this flow with the destruction of the filled metal or the polymer is doubted. In this research, we try to clarify the pressure distributions by this flow generation as well as its dynamics when chewing. One of our goals is to enable an objective design of the shape of the dental fillings and the artificial tooth. Tooth has a very small uneven ground and a bluff body. In this case, to calculate a computational numerical simulation to solve the Navier-Stokes equations three dimension Cartesian coordinate system is employed.

  14. Cat and Dog Bites

    Science.gov (United States)

    ... Prevention and Wellness Staying Healthy Pets and Animals Cat and Dog Bites Cat and Dog Bites Pets and AnimalsPrevention and WellnessStaying Healthy Share Cat and Dog Bites Cat and dog bites are ...

  15. Spider bite.

    Science.gov (United States)

    Isbister, Geoffrey K; Fan, Hui Wen

    2011-12-10

    Spiders are a source of intrigue and fear, and several myths exist about their medical effects. Many people believe that bites from various spider species cause necrotic ulceration, despite evidence that most suspected cases of necrotic arachnidism are caused by something other than a spider bite. Latrodectism and loxoscelism are the most important clinical syndromes resulting from spider bite. Latrodectism results from bites by widow spiders (Latrodectus spp) and causes local, regional, or generalised pain associated with non-specific symptoms and autonomic effects. Loxoscelism is caused by Loxosceles spp, and the cutaneous form manifests as pain and erythema that can develop into a necrotic ulcer. Systemic loxoscelism is characterised by intravascular haemolysis and renal failure on occasion. Other important spiders include the Australian funnel-web spider (Atrax spp and Hadronyche spp) and the armed spider (Phoneutria spp) from Brazil. Antivenoms are an important treatment for spider envenomation but have been less successful than have those for snake envenomation, with concerns about their effectiveness for both latrodectism and loxoscelism. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. 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. ...

  17. Maximal bite force and its association with signs and symptoms of TMD, occlusion, and body mass index in a cohort of young adults.

    Science.gov (United States)

    Ahlberg, Jari P; Kovero, Outi A; Hurmerinta, Kirsti A; Zepa, Inta; Nissinen, Maunu J; Könönen, Mauno H

    2003-10-01

    The purpose of this population-based cohort was to measure maximal bite force (MBF) in the molar and incisal regions and to examine whether MBF was associated with TMD, gender, occlusion (in terms of overjet, overbite, and total number of occluding contacts), and body mass index (BMI). MBF in the molar and incisal regions was measured using a calibrated method in 384 (196 males, 188 females) and 357 (181 males, 176 females) subjects, respectively. Two attempts in each region (right molar, left molar, and incisal) were made in random order. The subjects completed a multiple-choice questionnaire including subjective symptoms of TMD and were subsequently clinically examined. Helkimo's clinical dysfunction index and BMI were calculated. The mean MBF value in the molar region was significantly higher in males (878 N, SD 194) than in females (690 N, SD 175) (p TMD and studied occlusal factors, unlike body mass, associate independently with MBF.

  18. Analysis of the bite force and mechanical design of the feeding mechanism of the durophagous horn shark Heterodontus francisci

    National Research Council Canada - National Science Library

    Huber, Daniel R; Eason, Thomas G; Hueter, Robert E; Motta, Philip J

    2005-01-01

    Three-dimensional static equilibrium analysis of the forces generated by the jaw musculature of the horn shark Heterodontus francisci was used to theoretically estimate the maximum force distributions...

  19. 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, ...

  20. Dog Bite Emergencies

    Science.gov (United States)

    ... Emergency Care Animal Welfare Veterinary Careers Public Health Dog bite emergencies What do I do if I’ ... vaccination records. What do I do if my dog bites someone? Dog bites are scary for everyone ...

  1. Spider Bites (For Parents)

    Science.gov (United States)

    ... TV, Video Games, and the Internet 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. Avoid Mosquito Bites

    Science.gov (United States)

    ... Submit What's this? Submit Button Past Emails Avoid Mosquito Bites Language: English (US) Español (Spanish) Recommend on ... finding a travel medicine clinic near you. Prevent Mosquito Bites While Traveling Mosquito bites are bothersome enough, ...

  3. Dog bites

    OpenAIRE

    Muñoz Leyva, Felipe; Pontificia Universidad Javeriana

    2011-01-01

    Introduction: Although no official data exists for Colombia, dog bites are not infrequent consults to the emergency department on a global scale. In the urban or rural setting, it is likely that Colombian emergency department physicians face patients with such consults in their clinical practice. It is imperative that those physicians become familiar with the current national guidelines and protocols for the attention of such patients, since he/she must act pertinently according to the resour...

  4. Dog bites

    OpenAIRE

    Muñoz Leyva, Felipe; Pontificia Universidad Javeriana

    2011-01-01

    Introduction: Although no official data exists for Colombia, dog bites are not infrequent consults to the emergency department on a global scale. In the urban or rural setting, it is likely that Colombian emergency department physicians face patients with such consults in their clinical practice. It is imperative that those physicians become familiar with the current national guidelines and protocols for the attention of such patients, since he/she must act pertinently according to the resour...

  5. High resolution {gamma}-spectroscopy at the big-bite spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Savran, D.; Ramspeck, K.; Zilges, A. [Technische Univ. Darmstadt (Germany). Inst. fuer Kernphysik; Berg, A.M. van den; Harakeh, M.N.; Woertche, H.J. [Kernfysisch Versneller Inst. (KVI), Groningen (Netherlands)

    2006-04-05

    An array of HPGe detectors has been set up at the Big-Bite Spectrometer at AGOR cyclotron of KVI Groningen to allow coincident measurements of the {gamma}-decay of nuclei excited in inelastic hadron scattering at 100-400 MeV incident energies. Compared to previous experiments, where NaI detectors have been used, the energy resolution of the {gamma}-detection could be improved by more than one order of magnitude to about {delta}E{sub {gamma}}/E{sub {gamma}}=0.2 % in the energy region of interest. The coincident measurement of the {gamma}-decay in inelastic hadron scattering experiments is very useful for the separation of nearby excitations, the assignment of multipolarities, the determination of branching ratios and to study the isospin character of bound excitations. The experimental setup and the results of a first ({alpha},{alpha}'{gamma}) test experiment at E{sub {alpha}}=136 MeV on {sup 58}Ni are presented. (orig.)

  6. High-speed atomic force microscopy: imaging and force spectroscopy.

    Science.gov (United States)

    Eghiaian, Frédéric; Rico, Felix; Colom, Adai; Casuso, Ignacio; Scheuring, Simon

    2014-10-01

    Atomic force microscopy (AFM) is the type of scanning probe microscopy that is probably best adapted for imaging biological samples in physiological conditions with submolecular lateral and vertical resolution. In addition, AFM is a method of choice to study the mechanical unfolding of proteins or for cellular force spectroscopy. In spite of 28 years of successful use in biological sciences, AFM is far from enjoying the same popularity as electron and fluorescence microscopy. The advent of high-speed atomic force microscopy (HS-AFM), about 10 years ago, has provided unprecedented insights into the dynamics of membrane proteins and molecular machines from the single-molecule to the cellular level. HS-AFM imaging at nanometer-resolution and sub-second frame rate may open novel research fields depicting dynamic events at the single bio-molecule level. As such, HS-AFM is complementary to other structural and cellular biology techniques, and hopefully will gain acceptance from researchers from various fields. In this review we describe some of the most recent reports of dynamic bio-molecular imaging by HS-AFM, as well as the advent of high-speed force spectroscopy (HS-FS) for single protein unfolding.

  7. Prevent Bite Wounds

    Science.gov (United States)

    ... Children > Health Issues > Conditions > Prevention > Prevent Bite Wounds ... animals or other humans. Consider the following statistics: there are about 4.5 million dog bites reported annually in the United States, along ...

  8. Bites and stings.

    Science.gov (United States)

    Charles, Janice; Fahridin, Salma; Britt, Helena

    2009-11-01

    Of the 426 bite or sting problems managed, 312 (73%) were caused by insects. There were 114 other types of bites recorded, the most common being dog and spider bites. There were five cases of toxicity from aquatic animal stings or adverse reactions to bee stings (Table 1).

  9. The BigBite Drift Chambers for the Measurement of GE^n at High Q^2 in Hall A

    Science.gov (United States)

    Craver, Brandon

    2006-10-01

    A precision measurement of the electric form factor of the neutron G^nE has been carried out in Jefferson Lab's Hall A for Q^2 values of 1.2 to 3.5 GeV^2 using a highly polarized ^3He target and the quasi-elastic semi-exclusive ^3He(e, e^'n ) reaction. The experiment detected the ejected neutron with an array of scintillators and the scattered electron with the newly commissioned BigBite spectrometer. This new spectrometer has a large angular acceptance (80 msr), complementing the existing 6 msr high-resolution spectrometers, and will enable a new generation of low-rate experiments with lower resolution requirements. A package of three multi-wire drift chambers was constructed in order to allow the spectrometer to operate under high rate conditions and achieve a spatial resolution of 2˜00 μm. Novel construction techniques used for the drift chambers will be discussed. Online results showing chamber performance at raw hit rates up to 20 MHz per plane will be presented.

  10. Camouflage of a high-angle skeletal Class II open-bite malocclusion in an adult after mini-implant failure during treatment.

    Science.gov (United States)

    Franzotti Sant'Anna, Eduardo; Carneiro da Cunha, Amanda; Paludo Brunetto, Daniel; Franzotti Sant'Anna, Claudia

    2017-03-01

    The treatment of skeletal anterior open-bite malocclusion requires complex orthodontic planning that considers its multifactorial etiology, treatment limitations, and high relapse rates. This case report illustrates a successful treatment approach for a skeletal high-angle Class II malocclusion in an adult with a severe open bite. The treatment consisted of a high-pull headgear therapy after mini-implants failure during fixed orthodontic therapy. Adequate esthetics and function were achieved. Despite its low probability, the unexpected event of mini-implant loosening during complex treatments should be considered. Therefore, classic orthodontic mechanics should be established, especially when treating patients for whom invasive procedures such as miniplates or orthognathic surgery are not available options.

  11. Spider Bite in Iran.

    Science.gov (United States)

    Sanaei-Zadeh, Hossein

    2017-07-01

    Some of the world's most dangerous spiders have been certified in some areas of Iran. Spider bites are common in some geographical areas, and are sporadic in some regions. Spider bites can be classified as latrodectism or loxoscelism. If the patient had not seen the spider, the clinical manifestations of latrodectism could be easily mistaken for other types of bite or sting; or an infectious disease, and withdrawal symptoms, and also loxoscelism could be mistaken for cellulitis, various types of skin infection, or even a sting from a Gadim scorpion (Hemiscorpius lepturus). Given the nonspecific presentation of spider bites, one must keep the diagnosis in mind, and question patients, regarding possible exposure to spiders. Physicians recommend becoming familiar with the geographical distribution of Iranian dangerous spiders, clinical manifestations, and management of their bites. The most useful treatment for spider bite is anti-venom administration. Producing spider bite anti-venom in the Razi Vaccine and Serum Research Institute is under investigation.

  12. Overview of high-Q2 nucleon form factor program with Super BigBite Spectrometer in JLab's Hall A

    Science.gov (United States)

    Puckett, Andrew; Jefferson Lab Hall A; Super BigBite Spectrometer Collaboration

    2017-01-01

    The elastic electromagnetic form factors (EMFFs) of the nucleon describe the impact-parameter-space distributions of electric charge and magnetization in the nucleon in the infinite momentum frame. The form factors are among the simplest and most fundamental measurable dynamical quantities describing the nucleon's structure. Precision measurements of the nucleon form factors provide stringent benchmarks testing the most sophisticated theoretical models of the nucleon, as well as ab initio calculations in lattice QCD and continuum non-perturbative QCD calculations based on the Dyson-Schwinger equations. Measurements at momentum transfers Q in the few-GeV range probe the theoretically challenging region of transition between the non-perturbative and perturbative regimes of QCD. The recent upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) to a maximum electron beam energy of 11 GeV will facilitate the measurement of the nucleon helicity-conserving (F1) and helicity-flip (F2) form factors of both proton and neutron to Q2 > 10 GeV2, In this talk, I will present an overview of the Super BigBite Spectrometer, currently under construction in CEBAF's experimental Hall A, and its physics program of high-Q2 nucleon EMFF measurements. Supported by US DOE award DE-SC0014230.

  13. 咬合垂直距离与咀嚼肌肌电、咬合力关系的研究%Relationship between vertical dimension and bite force as well as electromyography in edentulous people

    Institute of Scientific and Technical Information of China (English)

    温从生; 刘丽; 费雪芬

    2015-01-01

    目的:研究老年无牙颌患者垂直距离和咬合力、咀嚼肌肌电幅值的关系,为临床上确立正常垂直距离提供参考。方法研究对象来自浙江大学附属口腔医院就诊的10位老年无牙牙合患者,用常规法确定垂直距离,以正常咬合垂直距离为基准位(M位),间隔0.5 mm形成13个咬合垂直距离。应用咬合力计测量患者不同垂直距离的咬合力,同时用记录双侧颞肌前束、咬肌的肌电活动,对垂直距离、咬合力和肌电进行统计研究。结果①无牙颌患者的咬合力与垂直距离呈正相关(P <0.05)。②标准化咬肌(NMM)和标准化颞肌前束肌电幅值(NATM)与垂直距离呈负相关(P <0.05)。③颞肌前束肌电/咬合力( ATM/ BF)、咬肌肌电/咬合力(MM/ BF)比值与着垂直距离呈负相关(P <0.05)。结论①随着垂直距离的增加,最大咬合力增大,正常咬合垂直距离并非产生最大咬合力的区域。②随着咬合垂直距离的增加,咬肌的肌电活动明显下降,颞肌前束的肌电活动变化则不及咬肌明显。③咬肌肌电/咬合力、颞肌前束肌电活动/咬合力比值均随着咬合垂直距离的增加而减小。④在正常咬合垂直附近有一稳定区,该区内最大咬合力、咬肌以及颞肌前束的肌电活动均不出现明显变化。%Objective To investigate the relationship between vertical dimension and bite force as well as electromyography (EMG) in elderly edentulous people,and to provide references for determining normal vertical dimension in clinic. Methods 10 edentulous subjects who went to the Affiliated Stomatological Hospital,College of Medicine,Zhejiang University were chosen. The normal vertical dimension was measured by conventional method. Based on the normal vertical dimension (M position),other 12 vertical dimensions were settled at every 0. 5 mm. Bite force at different vertical

  14. High-resolution traction force microscopy.

    Science.gov (United States)

    Plotnikov, Sergey V; Sabass, Benedikt; Schwarz, Ulrich S; Waterman, Clare M

    2014-01-01

    Cellular forces generated by the actomyosin cytoskeleton and transmitted to the extracellular matrix (ECM) through discrete, integrin-based protein assemblies, that is, focal adhesions, are critical to developmental morphogenesis and tissue homeostasis, as well as disease progression in cancer. However, quantitative mapping of these forces has been difficult since there has been no experimental technique to visualize nanonewton forces at submicrometer spatial resolution. Here, we provide detailed protocols for measuring cellular forces exerted on two-dimensional elastic substrates with a high-resolution traction force microscopy (TFM) method. We describe fabrication of polyacrylamide substrates labeled with multiple colors of fiducial markers, functionalization of the substrates with ECM proteins, setting up the experiment, and imaging procedures. In addition, we provide the theoretical background of traction reconstruction and experimental considerations important to design a high-resolution TFM experiment. We describe the implementation of a new algorithm for processing of images of fiducial markers that are taken below the surface of the substrate, which significantly improves data quality. We demonstrate the application of the algorithm and explain how to choose a regularization parameter for suppression of the measurement error. A brief discussion of different ways to visualize and analyze the results serves to illustrate possible uses of high-resolution TFM in biomedical research. © 2014 Elsevier Inc. All rights reserved.

  15. 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, ...

  16. Poor visualization during direct laryngoscopy and high upper lip bite test score are predictors of difficult intubation with the GlideScope videolaryngoscope.

    Science.gov (United States)

    Tremblay, Marie-Hélène; Williams, Stephan; Robitaille, Arnaud; Drolet, Pierre

    2008-05-01

    The GlideScope videolaryngoscope allows equal or superior glottic visualization compared with direct laryngoscopy, but predictive features for difficult GlideScope intubation have not been identified. We undertook this prospective study to identify patient characteristics associated with difficult GlideScope intubation. Demographic and morphometric factors were recorded preoperatively for 400 patients undergoing anesthesia with endotracheal intubation. After induction, direct laryngoscopy was performed in all patients to assess the Cormack and Lehane grade of glottic visualization followed by GlideScope intubation. The number of attempts and time needed for intubation were recorded. Univariate and multivariate analyses were performed to identify the characteristics associated with difficult GlideScope intubation. Intubation required 1, 2, and 3 attempts in 342, 48, and 9 participants, respectively, with one failure. Mean time for intubation was 21 +/- 14 s. After univariate analysis, the following characteristics were significantly correlated (P intubate and/or multiple attempts: older age, male sex, history of snoring, high Mallampati class, small mouth opening, short sternothyroid and manubriomental distances, large neck circumference, high upper lip bite test score, and high Cormack and Lehane grade during direct laryngoscopy. However, after introducing these variables in nominal logistic and proportional hazard multiple regression models, only high Cormack and Lehane grade during direct laryngoscopy, high upper lip bite test score, and short sternothyroid distance were significantly associated with multiple attempts or lengthier intubations. Despite a high success rate, intubation with the GlideScope is likely to be more challenging in patients with high Cormack and Lehane grade during direct laryngoscopy, high upper lip bite test score, or short sternothyroid distance.

  17. Rat Bite Fever

    Science.gov (United States)

    ... Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who ... ingestion of contaminated food or milk products (Haverhill fever). Most cases in the United States are caused ...

  18. Insect bites and stings

    Science.gov (United States)

    ... likely to cause itching than pain. Insect and spider bites cause more deaths from venom reactions than bites from snakes. ... are harmless. If possible, bring the insect or spider that bit you with you when you go for medical treatment so it can be identified.

  19. Management of vascular trauma from dog bites

    National Research Council Canada - National Science Library

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

    2013-01-01

    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...

  20. Bite Mark Analysis

    Directory of Open Access Journals (Sweden)

    SK Padmakumar

    2014-07-01

    Full Text Available Bite mark analysis plays an important role in personal identi- fi cation in forensic odontology. They are commonly seen in violent crimes such as sexual assaults, homicides, child abuse, etc. Human bites are common on the face and are usually seen on prominent locations of the face such as the ears, nose and lips. Individual characteristics recorded in the bite marks such as fractures, rotations, attrition, and congenital malformations are helpful in identifying the individual who caused it. We are reporting the case of a 55-year-old lady with bite marks on her left ear, who was allegedly assaulted by the suspect. On the basis of characteristic features of the suspect’s dentition, it was concluded that the bite marks seen on the victim was most probably caused by the suspect.

  1. The influence of gender and bruxism on the human maximum bite force Avaliação da influência do gênero e do bruxismo na força máxima de mordida

    Directory of Open Access Journals (Sweden)

    Patrícia dos Santos Calderon

    2006-12-01

    Full Text Available The objective of this research was to evaluate the influence of gender and bruxism on the maximum bite force. The concordance for the physical examination of bruxism between examiners was also evaluated. One hundred and eighteen individuals, from both genders, bruxists and non-bruxists, with an average age of 24 years, were selected for this purpose. For group establishment, every individual was submitted to a specific physical examination for bruxism (performed by three different examiners. Subjects were then divided into four groups according to gender and the presence of bruxism. The maximum bite force was measured using a gnathodynamometer at the first molar area, three times on each side, performed twice. The two measurements were made with a 10-day interval. The highest value was recorded. The mean maximum bite force was statistically higher for males (587.2 N when compared to females (424.9 N (p0.05. The concordance between examiners for physical examination of bruxism was considered optimal.O objetivo dessa pesquisa foi avaliar a influência do gênero e do bruxismo na força máxima de mordida. A concordância interexaminadores para o exame físico de bruxismo também foi avaliada. Cento e dezoito voluntários, com idade média de 24 anos, divididos por gênero e pela presença de bruxismo, foram selecionados. Para o estabelecimento da amostra todos os voluntários foram submetidos a um exame físico específico para bruxismo (realizado por três examinadores. Então, os voluntários foram divididos em quarto grupos de acordo com o gênero e a presença de bruxismo. A força máxima de mordida foi mensurada, com o auxílio de um gnatodinamômetro, na região de primeiro molar, três vezes de cada lado, em duas sessões distintas. As sessões foram separadas por um intervalo de 10 dias. O maior valor dentre os doze obtidos, foi utilizado como sendo a força máxima. A força máxima de mordida foi estatisticamente maior para o g

  2. Expression of TypeⅠCollagen mRNA in Rat Molar Periodontal Ligament Under Normal Bite Force%正常力大鼠磨牙牙周膜Ⅰ型胶原mRNA的表达

    Institute of Scientific and Technical Information of China (English)

    刘飞; 赵云凤; 王华蓉; 李甘地

    2001-01-01

    Objective:The main component of the periodontal ligament(PDL) is collagen fiber, especially typeⅠcollagen, and collagen plays an important role in PDL. The aim of this study is to observe the expression of rat PDL mRNA under normal bite force and to investigate the molecular mechanisms of these changes in type Ⅰ collagen mRNA.Methods: 40 male Wistar rats were used, and animals were intra_cardiac perfused with a solution of 4% polyformaldehyde under anesthesia. Dissected mandibles were immersed in the same fixation for 6 hours and subsequently decalcified in EDTA. The demineralized specimens were embedded in paraffin and cut into slices with thickness 5 μm. The probe was synthesized and labeled with digoxigenin. Expression of typeⅠcollagen mRNA was measured by using in situ hybridization(ISH).Results: Under the normal bite force , the mRNA expression of typeⅠ collagen was very strong on the whole, including the alveolar bone side, the root side and the area between them. Positive signals were located mainly in the cytoplasm and some in the nuclei. But the mRNA expression of typeⅠ collagen still had spatial characteristics. The signals in some fibroblasts were apparently stronger than those in other fibroblasts in the apical 1/3 fragment of the roots. The signal of typeⅠ collagen mRNA was strong near the root sides. The expression signal on the proximal alveolar walls was strong,however, on the distal alveolar wall, there was no expression.Conclusion: The expression of typeⅠcollagen mRNA is closely related with bite force.%目的:初探正常咬合力下大鼠牙周膜Ⅰ型胶原在分子水平的改建情况。方法:选用雄性Wistar大鼠,采用地高辛标记寡核苷酸探针原位杂交法,检测大鼠牙周膜Ⅰ型胶原mRNA的表达情况。结果:大鼠磨牙牙周膜有很强的Ⅰ型胶原信号,分布基本均匀,但仍具有一定的空间特异性:近中侧牙槽骨骨壁上有较多致密信号,而远中侧无信号。结论:

  3. Rat Bite Fever Resembling Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Ripa Akter

    2016-01-01

    Full Text Available Rat bite fever is rare in Western countries. It can be very difficult to diagnose as blood cultures are typically negative and a history of rodent exposure is often missed. Unless a high index of suspicion is maintained, the associated polyarthritis can be mistaken for rheumatoid arthritis. We report a case of culture-positive rat bite fever in a 46-year-old female presenting with fever and polyarthritis. The clinical presentation mimicked rheumatoid arthritis. Infection was complicated by discitis, a rare manifestation. We discuss the diagnosis and management of this rare zoonotic infection. We also review nine reported cases of rat bite fever, all of which had an initial presumptive diagnosis of a rheumatological disorder. Rat bite fever is a potentially curable infection but can have a lethal course if left untreated.

  4. Remote Robot Control With High Force-Feedback Gain

    Science.gov (United States)

    Kim, Won S.

    1993-01-01

    Improved scheme for force-reflecting hand control of remote robotic manipulator provides unprecedently high force-reflection gain, even when dissimilar master and slave arms used. Three feedback loops contained in remote robot control system exerting position-error-based force feedback and compliance control. Outputs of force and torque sensors on robot not used directly for force reflection, but for compliance control, while errors in position used to generate reflected forces.

  5. Rat-bite fever

    Science.gov (United States)

    Streptobacillary fever; Streptobacillosis; Haverhill fever; Epidemic arthritic erythema; Spirillary fever; Sodoku ... Rat-bite fever can be caused by 2 different bacteria, Streptobacillus moniliformis or Spirillum minus. Both of these are found in ...

  6. 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 ...

  7. 咀嚼压力增强对大鼠牙槽骨白细胞介素-1β表达的影响%Effect of increased bite force on the expression of IL-1β in rat alveolar bone osteoblasts

    Institute of Scientific and Technical Information of China (English)

    袁林; 周伟东; 赵云凤

    2001-01-01

    目的检测大鼠牙槽骨成骨细胞中IL-1β在正常及增强咀嚼压力状态下的动态表达,探讨IL-1β在牙槽骨改建中的分子机制。方法采用HE染色和免疫组化的方法,观察牙周形态变化以及牙槽骨成骨细胞中IL-1β蛋白表达。结果生理限度内咀嚼压力增强时,形态学显示大鼠牙周膜增宽、牙槽骨新骨形成;免疫组化观察到成骨细胞中IL-1β表达较正常咀嚼压力时明显增强。结论咀嚼压力增强促使牙周组织产生IL-1β明显增多,诱发了破骨功能,同时,还激活了成骨功能。提示IL-1β在咀嚼压力影响牙槽骨改建的过程中起着重要的调节作用。%Objective To explore the molecular mechanism of alveolar bone remodeling by studying the dynamic changes of IL- 1β expression in rat alveolar bone osteoblasts. Methods Rat models of increased bite force of the back teeth were established, and the expression of IL-1β in the alveolar bone osteoblasts were determined by HE staining and immunohistochemistry. Observation of the changes in the histological morphology of the periodontium was conducted microscopically. Rats with normal bite force served as control. Results The increase of bite force (within the physiological limit) induced the widening of the periodontal ligament and the osteogenesis in the alveolar bone. Significant enhancement of IL-1β expression was observed in the osteoblasts of rats with increased bite force, in comparison with that in the rats with normal bite force. Conclusion Increased bite force causes higher expression levels of IL-1β in the alveolar bone osteoblasts, initiating the destruction process of the bone but simultaneously the activation of the ossification, suggesting that IL-1β plays an important role in the regulation of periodontium remodeling in response to changes in the bite force

  8. [The dental and skeletal effects of the jumping-the-bite plate and high-pull headgear combination. A clinical study of treated patients].

    Science.gov (United States)

    Wichelhaus, A; Sander, F G

    1995-07-01

    While planning treatment of the 30 patients with a dental and skeletal class II anomaly on which this study is based, the primary treatment goals were correction of the dental and skeletal structures and attenuation of vertical growth by means of influencing the maxillary skeletal structures and the resultant mandibular reaction. The desired treatment results were achieved in all patients. Even so, however, the effects on individual patients in respect to skeletal influences were markedly different. It was especially helpful that during therapy simultaneously with exerting influence on the maxillary base plane, the influencing of the occlusal plane occurred in the same direction. Through the additional application of high-pull headgear, maxillary growth was clearly restrained and the inclination of the maxillary base plane inhibited. Even difficult skeletal discrepancies, sagittal as well as vertical, can be treated with the bite-jump appliance in combination with a high-pull headgear. This also makes it possible to achieve protrusive repositioning of the mandible in patients with a pronounced vertical growth pattern without causing on open bite. In retrospective the patients' treatment plans proved to be completely appropriate, however, the fact should not be overlooked that changing the occlusal plane is essential for the realization of a positive therapeutic result.

  9. Animal Bites - Multiple Languages

    Science.gov (United States)

    ... V W XYZ List of All Topics All Animal Bites - Multiple Languages To use the sharing features on this page, ... Library of Medicine Vietnamese (Tiếng Việt) Expand Section Animal Bites and Scratches - Tiếng Việt (Vietnamese) ... Health Information Translations Characters not displaying correctly on this page? See language display issues . Return to the MedlinePlus Health Information ...

  10. High-resolution noncontact atomic force microscopy.

    Science.gov (United States)

    Pérez, Rubén; García, Ricardo; Schwarz, Udo

    2009-07-01

    original papers authored by many of the leading groups in the field with the goal of providing a well-balanced overview on the state-of-the-art in this rapidly evolving field. These papers, many of which are based on notable presentations given during the Madrid conference, feature highlights such as (1) the development of sophisticated force spectroscopy procedures that are able to map the complete 3D tip-sample force field on different surfaces; (2) the considerable resolution improvement of Kelvin probe force microscopy (reaching, in some cases, the atomic scale), which is accompanied by a thorough, quantitative understanding of the contrast observed; (3) the perfecting of atomic resolution imaging on insulating substrates, which helps reshape our microscopic understanding of surface properties and chemical activity of these surfaces; (4) the description of instrumental and methodological developments that pave the way to the atomic-scale characterization of magnetic and electronic properties of nanostructures, and last but not least (5) the extension of dynamic imaging modes to high-resolution operation in liquids, ultimately achieving atomic resolution. The latter developments are already having a significant impact in the highly competitive field of biological imaging under physiological conditions. This special issue of Nanotechnology would not have been possible without the highly professional support from Nina Couzin, Amy Harvey, Alex Wotherspoon and the entire Nanotechnology team at IOP Publishing. We are thankful for their help in pushing this project forward. We also thank the authors who have contributed their excellent original articles to this issue, the referees whose comments have helped make the issue an accurate portrait of this rapidly moving field, and the entire NC-AFM community that continues to drive NC-AFM to new horizons.

  11. 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.

  12. Rhabdomyolysis and Acute Renal Failure After Fire Ant Bites

    OpenAIRE

    Koya, Supriya; Crenshaw, Daryl; Agarwal, Anupam

    2007-01-01

    We describe a 59-year-old patient who developed acute renal failure because of rhabdomyolysis after extensive red fire ant bites. This case illustrates a serious systemic reaction that may occur from fire ant bites. Consistent with the clinical presentation in rhabdomyolysis associated with non-traumatic causes, hyperkalemia, hypophosphatemia, hypocalcemia, and high anion gap acidosis were not observed in this patient. While local allergic reactions to fire ant bites are described in the lite...

  13. Protein high-force pulling simulations yield low-force results.

    Directory of Open Access Journals (Sweden)

    Seth Lichter

    Full Text Available All-atom explicit-solvent molecular dynamics simulations are used to pull with extremely large constant force (750-3000 pN on three small proteins. The introduction of a nondimensional timescale permits direct comparison of unfolding across all forces. A crossover force of approximately 1100 pN divides unfolding dynamics into two regimes. At higher forces, residues sequentially unfold from the pulling end while maintaining the remainder of the protein force-free. Measurements of hydrodynamic viscous stresses are made easy by the high speeds of unfolding. Using an exact low-Reynolds-number scaling, these measurements can be extrapolated to provide, for the first time, an estimate of the hydrodynamic force on low-force unfolding. Below 1100 pN, but surprisingly still at extremely large applied force, intermediate states and cooperative unfoldings as seen at much lower forces are observed. The force-insensitive persistence of these structures indicates that decomposition into unfolded fragments requires a large fluctuation. This finding suggests how proteins are constructed to resist transient high force. The progression of [Formula: see text] helix and [Formula: see text] sheet unfolding is also found to be insensitive to force. The force-insensitivity of key aspects of unfolding opens the possibility that numerical simulations can be accelerated by high applied force while still maintaining critical features of unfolding.

  14. Marine animal stings or bites

    Science.gov (United States)

    ... poisonous bites or stings from any form of sea life, including jellyfish. There are about 2,000 species ... bites or stings from various types of marine life, including: jellyfish ... sea urchins, sea anemone, hydroid, coral, cone shell, sharks, ...

  15. Animal bite - first aid - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100214.htm Animal bite - first aid - series—Procedure, part 1 To ... D.A.M., Inc. Related MedlinePlus Health Topics Animal Bites A.D.A.M., Inc. is accredited ...

  16. Compartment Syndrome Following Snake Bite

    National Research Council Canada - National Science Library

    Dhar, Dinesh

    2015-01-01

    .... The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite...

  17. 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

  18. 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

  19. Bite by moray eel

    Directory of Open Access Journals (Sweden)

    JP Barreiros

    2008-01-01

    Full Text Available Injuries caused by moray eels are not a common problem, but are distributed throughout the globe, affecting mainly fishermen while manipulating hooked or netted fish. On a lesser scale, scuba divers and snorkelers, practicing or not spear fishing, are occasional victims of bites. With more than 185 species distributed among 15 genera, mostly in tropical to temperate shallow water, moray eels easily come into contact with humans and occasional injuries are not uncommon. The current study reports one case of moray eel bite and discusses the circumstances in which the accident happened, as well as wound evolution and therapy.

  20. High-Multipolar Effects on Dispersive Forces

    CERN Document Server

    Noguez, C; Esquivel-Sirvent, R; Villarreal, C; Noguez, Cecilia; Roman-Velazquez, Carlos E.

    2003-01-01

    We show that the dispersive force between a spherical nanoparticle (with a radius $\\le$ 100 nm) and a substrate is enhanced by several orders of magnitude when the sphere is near to the substrate. We calculate exactly the dispersive force in the non-retarded limit by incorporating the contributions to the interaction from of all the multipolar electromagnetic modes. We show that as the sphere approaches the substrate, the fluctuations of the electromagnetic field, induced by the vacuum and the presence of the substrate, the dispersive force is enhanced by orders of magnitude. We discuss this effect as a function of the size of the sphere.

  1. African tick bite fever

    DEFF Research Database (Denmark)

    Johansen, Jakob Aaquist; Thybo, Søren

    2011-01-01

    The incident of spotted fever imported to Denmark is unknown. We present a classic case of African Tick Bite Fever (ATBF) to highlight a disease, which frequently infects wildlife enthusiasts and hunters on vacation in South Africa. ATBF has a good prognosis and is easily treated with doxycyclin...

  2. 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.

  3. 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

  4. Perawatan Ortodontik pada Maloklusi Klas II Divisi 1 dengan Overjet Besar dan Palatal Bite Menggunakan Alat Cekat Teknik Begg

    OpenAIRE

    Reni Kurniasari; Wayan Ardhana; Christnawati Christnawati

    2014-01-01

    Maloklusi Klas II divisi 1 sering disertai overjet besar dan palatal bite, koreksi overjet besar dan palatal bite akan sulit dilakukan dan membutuhkan waktu yang lama. Pada perawatan ortodontik menggunakan teknik Begg koreksi overjet besar dan palatal bite dapat dilakukan secara bersamaan karena memakai differential force. Tujuan artikel ini adalah untuk menyajikan hasil koreksi overjet besar dan palatal bite pada kasus maloklusi klas II divisi 1 menggunakan alat ortodontik cekat teknik Begg....

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

    Directory of Open Access Journals (Sweden)

    Masoumeh Ghane Kisomi

    Full Text Available 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.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.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.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 barriers of tick bite prevention.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byung I., E-mail: ByungKim@boisestate.edu [Department of Physics, Boise State University, 1910 University Drive Boise, ID 83725-1570, United States of America (United States); Boehm, Ryan D. [Department of Physics, Boise State University, 1910 University Drive Boise, ID 83725-1570, United States of America (United States)

    2013-02-15

    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.

  7. [In relation to Cleopatra and snake bites].

    Science.gov (United States)

    Espinoza, R

    2001-10-01

    Cleopatra VII, one of the last Egyptian sovereigns of the ptolomeic dynasty, is envisioned as a mythic figure, surrounded by intrigues and mystery. her mysterious death was caused, according to history, by a snake bite. This article shows some instances of great Cleopatra's life and the state of the art on snake venoms. Even at the present time, snake bites are a public health problem in Asia, Africa, Central and South America, causing more than 25,000 deaths every year. Most snake venoms have a protein structure and cause neurotoxic and hemolytic effects, altering coagulation and fibrinolysis. The mortality due to snake bites fluctuates between 1 and 22%. Specific treatment includes the use of specific antiserums with highly purified components.

  8. A two year study of verified spider bites in Switzerland and a review of the European spider bite literature.

    Science.gov (United States)

    Nentwig, Wolfgang; Gnädinger, Markus; Fuchs, Joan; Ceschi, Alessandro

    2013-10-01

    During a two-year study, all spider bites recorded by Swiss primary care physicians were reported to the Swiss Toxicological Information Centre and all collected spiders were identified. A total of 14 verified spider bites were recorded, involving five species from four families: Zoropsis spinimana (five cases), Cheiracanthium punctorium (four cases), Tegenaria atrica (three cases) and one case of Malthonica ferruginea (= Tegenaria ferruginea) (both Agelenidae), and one case of Amaurobius ferox (Amaurobiidae). The bites of all spider species produced relatively mild symptoms. Local symptoms such as moderate to severe pain, circumscribed swelling and redness were the only effects in most cases. Systemic symptoms were rare. There was complete recovery in all cases and all lesions healed completely without further damage or secondary disorders. Following a review of the European spider bite literature, the number of spider species capable of biting humans in Europe is considered to be much larger than could be concluded from this study. Most spider bites are restricted to species living synanthropically, thus promoted by climate and habitat change. The annual frequency of spider bites in Switzerland is estimated at 10-100 bites per million inhabitants, but this is predicted to increase due to the continuous arrival of new alien species, many of which have a high potential to establish in urban areas. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Myocarditis following katipo spider bite.

    Science.gov (United States)

    Crook, Ruth; Harrison, Nigel; Gibbons, Derek

    2010-05-14

    We report the case of a 22-year-old man who developed severe myocarditis following a presumed katipo spider bite. Katipo spiders are thought to be one of the most poisonous native creatures in New Zealand. No deaths from katipo spider bites have been reported since the 19th Century. A literature search reveals no previously reported cases of myocarditis following a bite from a katipo spider. The clinical presentation of latrodectism is discussed.

  10. Correlation study of the relationship between gravity center movement and bite force during the mixed dentition period%混合牙列期身体重心动摇和咬合力的相关性研究

    Institute of Scientific and Technical Information of China (English)

    杜小沛; 纪莹; 陆海涛; 张婷婷; 邱伟

    2016-01-01

    目的:调查混合牙列期身体重心动摇与咬合力之间的关系。方法56名处于Hellman咬合发育Ⅲ期A阶段的健康小学生纳入研究。通过检查咬合平衡中点与中线的距离( X)关系,X≤5 mm被划分为正中组,X>5 mm被划分为偏移组。使用自动姿态分析系统测定了身体平衡相关开闭眼时的重心动摇距离、重心动摇面积。使用牙齿压力感应装置Dental Prescale®测定了咬合接触面积、平均咬合力、最大咬合压力,咬合力和咬合平衡。结果咬合接触面积和咬合力的测试结果男女分别为18.1 mm2、712.2 N和14.1 mm2、541.8 N,差异均具有统计学意义(P<0.05)。咬合平衡中点正中组与偏移组的咬合接触面积、咬合力之间差异具有统计学意义(P <0.05)。咬合平衡中点正中组开、闭眼时期的重心动摇距离、面积明显小于偏移组,咬合平衡与开、闭眼时期的重心动摇距离、面积有关且具有统计学意义(P<0.05)。重心动摇稳定组的咬合接触面积大于动摇组,两者差异具有统计学意义(P<0.05)。结论 Hellman咬合发育Ⅲ期A阶段儿童咬合平衡和人体重心动摇存在相关性,咬合接触面积与身体重心动摇相互影响。%Objective To investigate the relationship between gravity center movement and bite force during the mixed dentition period. Methods Fifty-six healthy children with Hellman's Dental AgeⅢ A were selected from an ele-mentary school. The body balance, distance and area of gravity center movement ( GCM) were measured with automatic posture analytical devices. Occlusal abilities were measured with pressure-sensitive sheets ( Dental Prescale® ) , including occlusal contacts area, average occlusal pressure, maximum occlusal pressure, occlusal force and occlusal balance. Re-sults The occlusal contact area and bite force test results of male and female group were 18. 1 mm2 , 712. 2 N and 14. 1 mm2, 541. 8 N, The differences were statistically

  11. [Arthropod bite reactions and pyodermias].

    Science.gov (United States)

    Hengge, U R

    2008-08-01

    Tourists in the tropics often develop reactions to bites or stings of mosquitoes, fleas, mites, ants, bedbugs, beetles, larva, millipedes, spiders and scorpions. In addition, they may have fresh or salt water exposure to sponges, corals, jellyfish and sea urchins with resultant injury and inflammation. Bacterial skin infections (pyodermias) can follow bites or stings as well as mechanical trauma. The most common bacteria involved in skin infections are staphylococci and streptococci. For tourists, bacterial infections are often complicating a pruritic bite reaction and scratching. It is important to know the cause of the bite reaction and pyoderma in order to take appropriate therapeutic measures.

  12. Oral Mucous Membrane Irritation Test and Biting Force Measurement of a New Denture Adhesive%义齿稳固剂的口腔黏膜刺激性及对咬合力的影响

    Institute of Scientific and Technical Information of China (English)

    肖亚伟

    2011-01-01

    目的 初步探讨自行研制的纤维素类义齿稳固剂(denture adhesive,DA)对口腔黏膜的刺激性和临床应用效果.方法 健康金黄地鼠10只随机分为2组,麻醉后,其中1组动物口腔左侧黏膜放置DA浸提液,另1组置入阳性对照材料,2组动物口腔右侧黏膜均放置阴性对照材料.分别于1、4、6、8 h后肉眼观察局部黏膜改变,并做组织切片了解组织学改变.临床测定20例患者使用DA前后,新旧全口义齿最大咬合力的变化.结果 实验动物均未出现局部及全身的不良刺激反应.所研制的稳固剂可提高新旧全口义齿的最大咬合力,但仅旧义齿使用前后差异有统计学意义(t=3.584,P<0.01).结论 所研制的DA义齿稳固剂未见对口腔黏膜的不良刺激反应,DA可提高旧义齿的最大咬合力,有较好的临床应用前景.%Objective To evaluate local and systemic response to the developed synthetic denture adhesive( DA), by oral membrane irritation test. Clinical investigation was di~ussed in this article as well. Methods Ten hamsters were used in this research and divided into 2 groups evenly. The eluates of DA and positive control materials were fixed on the left of oral membrane of each 5 hamsters' pouch separately, while the negative materials were put on the right side of all the 10 tested animals. After 1 h, 4 h, 6 h and 8 h of local and systemic observation, the local oral membrane specimens were viewed under microscope. Twenty edentulous patients with complete dentures were selected for this research also.The maximum biting force was recorded before and after application of the adhesive to all the new and old dentures. Results The results showed that there were no local or systemic abnormal response to the test material. The clinical investigation data indicated that significantly greater biting forces were generated with old dentures than with the new dentures.Conclusion The developed DA exhibited no abnormal oral mucous membrane

  13. Animal bite incidence in the County of Shush, Iran

    Institute of Scientific and Technical Information of China (English)

    Hamid Kassiri; Ali Kassiri; Masoud Lotfi; Babak Shahkarami; Seyed-Sahar Hosseini

    2014-01-01

    Objective:To determine the epidemiology of animal bites during a five-year period(2004-2008) inShushCounty,Khuzestan province, southwesternIran.Methods:In a descriptive cross sectional study, all cases of animal bites referred to the health centers inShushCounty were investigated during2004-2008.The necessary data were recorded on the special questionnaire that contains questions about bite animal, age, sex, occupation, treatment, the bite site on the body and so forth.Results:Out of a total of2283 cases that underwent the animal bites during the mentioned five years,1771 people(77.6%) were male and511(22.4%) were female .Most cases were related to age groups10-20(33.4%) and20-30(22%) years.The average incidence rate of animal bite during these years was determined as2.82 cases per1000 people.The highest incidence rate was related to the year2007 with3 cases per1000 people.Animal bites in the winter(29.3%) and fall(29%) were more common.Almost86.5% and13.5% of the cases occurred in rural areas and urban areas, respectively.Nearly30% and20.4% of cases were students and farmers, respectively.A total of2155(94.4%) and86(3.8%) bites occurred by the dog and cat, respectively.The greatest bite place on the body was in the feet(81.4%) and in the hands(13%(. During the study period,2162 cases(94.7%) were treated with an incomplete regimen, and120 cases(5.3%) were treated with a complete regimen.Conclusions:Because the cost of prevention after biting for the health system is high, so, preventive programs must be concentrated on public health instruction, particularly in villagers, students, farmers and the owners of the domestic animals.

  14. Take an Adventure Bite

    Directory of Open Access Journals (Sweden)

    Brian Brandt

    2013-06-01

    Full Text Available The Adventure Bites - Cooking with Kids program enhanced nutrition curriculum by including a Life Skill development focus and a family night - to improve youth nutrition behaviors. The data was collected using the WSU 4-H Life Skills pre-post youth evaluations, staff surveys, a parent retrospective pre-post survey, and comparison data from non-program sites. The results support adding Life Skills and family night events into youth nutrition curricula. There are opportunities to improve evaluation and do further testing, to determine what the individual impact of Life Skill development and/or individual impact of having family nights had on changes in youth behaviors regarding nutrition.

  15. 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.

  16. 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 this ... effects of a bite from the funnel-web spider. Male funnel-web spiders are more poisonous than females. This article ...

  17. Spider bites - Assessment and management.

    Science.gov (United States)

    Braitberg, George; Segal, Leslie

    2009-11-01

    Spider bite is common, but most species cause minimal or no effects. Patients may be misinformed regarding the nature and consequences of a bite. Understanding the current literature can assist the physician in the management of spider bite patients. This article reviews the current literature on spider bites and describes the clinical assessment and management of the medically important spider bites. Most spider bite is minor and causes nothing more than local irritation. Some spiders can cause significant morbidity and rarely, mortality. Lay identification of the spider has not been shown to be reliable. Latrodectism (red back spider envenomation) is characterised by pain (local, radiating, and regional); systemic symptoms occur less commonly. Funnel web spider bite is a medical emergency; a pressure immobilisation bandage should be applied and the patient transferred to a hospital with available antivenom and resuscitation facilities. Clinicians must consider spider bite in the differential diagnosis of unexplained autonomic and neurological dysfunction, particularly in children. In Australia, skin ulceration is more likely to be an infective, inflammatory or traumatic cause than a case of necrotising arachnidism.

  18. 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)

  19. 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

  20. Evaluation of the stability of open bite treatment using a removable appliance with palatal crib combined with high-pull chincup

    Directory of Open Access Journals (Sweden)

    Fernando Pedrin Carvalho Ferreira

    2012-12-01

    Full Text Available OBJECTIVE: The aim of this prospective study was to cephalometrically analyze the stability of dentoalveolar and skeletal changes produced by a removable appliance with palatal crib associated to high-pull chincup in individuals with anterior open bite treated for 12 months, and compare them to individuals with similar malocclusion and age, not submitted to orthodontic treatment, also followed for the same period. METHODS: Nineteen children with a mean age of 9.78 years old treated for 12 months with a removable appliance with palatal crib associated with chincup therapy were evaluated after 15 months (post-treatment period and compared with a control group of 19 subjects with mean age of 9.10 years with the same malocclusion that was followed-up for the same period. Seventy-six lateral cephalograms were evaluated at T1 (after correction and T2 (follow-up and cephalometric variables were analyzed by statistical tests. RESULTS: The results did not show significant skeletal, soft tissue or maxillary dentoalveolar changes. Overall, treatment effects on the experimental group were maintained at T2 evaluation with an increase of 0.56 mm in overbite. Overjet and maxillary incisors/molars position (vertical and sagittal remained essentially unchanged during the study period. Only mandibular incisors showed significant changes (labial inclination and protrusion compared to control group. CONCLUSIONS: Thus, it can be concluded that the early open bite treatment with a removable appliance and palatal crib associated with high-pull chincup therapy provided stability of 95%.OBJETIVO: avaliar cefalometricamente a estabilidade das alterações dentoesqueléticas e tegumentares, no protocolo de tratamento com o aparelho removível com grade palatina associado à mentoneira, em jovens portadores de mordida aberta anterior tratados por 12 meses, comparando-os com um grupo de jovens portadores de má oclusão semelhante que não foram submetidos ao tratamento

  1. High-throughput screening for modulators of cellular contractile force

    CERN Document Server

    Park, Chan Young; Tambe, Dhananjay; Chen, Bohao; Lavoie, Tera; Dowell, Maria; Simeonov, Anton; Maloney, David J; Marinkovic, Aleksandar; Tschumperlin, Daniel J; Burger, Stephanie; Frykenberg, Matthew; Butler, James P; Stamer, W Daniel; Johnson, Mark; Solway, Julian; Fredberg, Jeffrey J; Krishnan, Ramaswamy

    2014-01-01

    When cellular contractile forces are central to pathophysiology, these forces comprise a logical target of therapy. Nevertheless, existing high-throughput screens are limited to upstream signaling intermediates with poorly defined relationship to such a physiological endpoint. Using cellular force as the target, here we screened libraries to identify novel drug candidates in the case of human airway smooth muscle cells in the context of asthma, and also in the case of Schlemm's canal endothelial cells in the context of glaucoma. This approach identified several drug candidates for both asthma and glaucoma. We attained rates of 1000 compounds per screening day, thus establishing a force-based cellular platform for high-throughput drug discovery.

  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. 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 baseball/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.

  5. INTERPARTICLE FORCES IN HIGH TEMPERATURE FLUIDIZATION OF GELDART A PARTICLES

    Institute of Scientific and Technical Information of China (English)

    Heping Cui; Jamal Chaouki

    2004-01-01

    Previous reports and current studies show that fluidization of some Geldart A particles is enhanced by increasing bed temperature. Both the averaged local particle concentration and the particle concentration in the dense phase decrease with increasing bed temperature, at constant superficial gas velocities. However, conventional models fail to predict these changes, because the role of interparticle forces is usually neglected at different bed temperatures.Here, the interparticle forces are analyzed to explore the mechanism of gas-solid fluidization at high temperatures. Indeed, as the temperature increases, the interparticle attractive forces decrease while the interparticle repulsive forces increase. Consequently, fluidization behaviors of some Geldart A particles seem to increasingly shift from typical Geldart A towards B with increasing temperature.

  6. Dilemmas in Treatment of Recurrent Recalcitrant Dental Anterior Open Bite.

    Science.gov (United States)

    Palencar, Adrian J

    2016-01-01

    An anterior open bite is one of the most difficult occlusal abnormalities to treat. Quite often this aberration entails dental component and/or skeletal component. The skeletal open bite will require intrusion of the posterior sextants with the assistance of bite blocks, temporary anchorage devices, high pull headgear, and as a last resort - orthognathic surgery. The orthodontic treatment should be augmented with the orofacial myofunctional therapy. In this article, the author describes 3 different variations of treatment of the dental anterior open bite, first on acrylic models, and then on the actual patients. Consideration should be given to patients with a 'short upper lip," and in this case, surgical correction should be entertained.

  7. Animal Bites of the Hand

    Science.gov (United States)

    ... your bite may be infected include: Swelling Redness Warmth Continued pain beyond 24 hours Drainage from the wound Signs that your infection may be spreading include: Red streaks up the arm or forearm Swollen glands ...

  8. Traveler's Health: Avoid Bug Bites

    Science.gov (United States)

    ... Blood Clots Bug Bites Business Travel Cold Climates Counterfeit Drugs Cruise Ship Travel Families with Children Fish ... insect repellents that contain at least 20% DEET (products include Cutter Backwoods and Off! Deep Woods) for ...

  9. Reversible myocarditis after spider bite.

    Science.gov (United States)

    Kara, Hasan; Ak, Ahmet; Bayir, Aysegul; Avci, Ahmet

    2013-04-08

    Black widow spiders (Latrodectus tredecimguttatus) are poisonous spiders endemic in Turkey. Latrodectus bites may cause myocarditis with increased cardiac enzymes. We treated two men (aged 20 and 33 years) who had myocarditis after black spider bites with leucocytosis and elevated levels of troponin I, creatine kinase and creatine kinase-MB fraction. Both patients had normal results on an ECG, and one patient had abnormal echocardiography with minimal left ventricular wall movement disorder. Both patients were hospitalised in the intensive care unit and treated with intravenous fluids, analgesics, spasmolytic drugs, tetanus prophylaxis and cardiac monitoring. The levels of troponin I, creatine kinase and creatine kinase-MB fraction improved, and the patients were discharged home on the third and fifth hospital day without complications. Myocarditis after a Latrodectus bite is rare, but may be associated with serious complications. Therefore, in regions endemic with Latrodectus spiders, prudent treatment of spider bites may include cardiac evaluation and monitoring.

  10. Ticks and Diseases: Bite Fright!

    Science.gov (United States)

    ... of this page please turn Javascript on. Feature: Ticks and Diseases Bite Fright! Past Issues / Spring - Summer ... can bring on serious health problems. What Are Ticks? If you spend any time outdoors, you've ...

  11. Functional morphology and bite performance of raptorial chelicerae of camel spiders (Solifugae).

    Science.gov (United States)

    van der Meijden, Arie; Langer, Franz; Boistel, Renaud; Vagovic, Patrik; Heethoff, Michael

    2012-10-01

    Solifugae are an understudied group of relatively large arachnids with well over 1000 species distributed on almost all major continents. These highly active predators utilize their large chelicerae for feeding, defense, burrowing and mating. We investigated the differences in cheliceral morphology and performance of two ecologically divergent species from North Africa; the cursorial Galeodes sp. and the burrowing Rhagodes melanus. Morphological data show differences in aspect ratio between the two species. Bite force measurements show Rhagodes (N=11) to be a much stronger biter than Galeodes (N=8), in terms of both absolute maximum force (Rhagodes 5.63 N, Galeodes 2.12 N) and force relative to cheliceral size. Synchrotron microtomographs of one specimen for each species reveal large differences in physiological cross-sectional area (PCSA) and estimated muscle stress, resulting in a much higher muscle stress in Rhagodes. This species also showed a longer muscle fiber length. Muscle volume and PCSA were found to differ between the two chelicerae in the two scanned specimens. Whereas Rhagodes reflects this morphological asymmetry in having a higher bite force in the right chelicera, Galeodes shows no such bias.

  12. Compartment Syndrome Following Snake Bite

    Directory of Open Access Journals (Sweden)

    Dinesh Dhar

    2015-03-01

    Full Text Available Snake bites are an important public health problem worldwide. Snake venom causes both systemic and local complications, which can prove fatal if not treated on time. The local effects of snake bite include tissue necrosis, edema, and compartment syndrome. Patients may also be left with permanent physical deformities due to residual sequelae of the snake bite. Compartment syndrome after a snake bite is an uncommon occurrence. The effects are more pronounced in children possibly due to the the reduced total dilution volume in children. The administration of anti-snake venom is the only specific therapy. Compartment syndrome occurs due to a vicious cycle of edema causing hypoxia and acidosis, which further increases capillary permeability and fluid extravasation. This results in a volume increase in the closed fascial compartment, which ultimately compromises circulation and causes irreversible muscle and nerve damage. Our report describes a case of upper limb compartment syndrome following a snake bite on the right wrist of a five-year-old girl who presented eight-hours after the snake bite to the emergency department of Nizwa Regional Referral Hospital. The patient received early and appropriate care but progressed to develop compartment syndrome for which she had to be taken to the operating theatre for emergency fasciotomy. All clinicians should be able to recognize the early symptoms and signs of an evolving compartment syndrome in absence of intracompartmental measuring equipment. The timely fasciotomy in our patient helped the patient achieve excellent functional results.

  13. Forensic odontology, part 4. Human bite marks.

    Science.gov (United States)

    Hinchliffe, J

    2011-04-23

    The aim of this paper is to give a brief overview of bite mark analysis: its usefulness and limitations. The study and analysis of such injuries is challenging and complex. The correct protocols for collection, management, preservation, analysis and interpretation of this evidence should be employed if useful information is to be obtained for the courts. It is now possible, with advances in digital technology, to produce more accurate and reproducible comparison techniques which go some way to preventing and reducing problems such as photographic distortions. Research needs to be continued to increase our knowledge of the behaviour of skin when bitten. However, when presented with a high quality bite mark showing good dental detail, and a limited, accessible number of potential biters, it can be extremely useful in establishing a link between the bitten person and the biter or excluding the innocent.

  14. Force

    CERN Document Server

    Graybill, George

    2007-01-01

    Forces are at work all around us. Discover what a force is, and different kinds of forces that work on contact and at a distance. We use simple language and vocabulary to make this invisible world easy for students to ""see"" and understand. Examine how forces ""add up"" to create the total force on an object, and reinforce concepts and extend learning with sample problems.

  15. Acceleration of objects to high velocity by electromagnetic forces

    Energy Technology Data Exchange (ETDEWEB)

    Post, Richard F

    2017-02-28

    Two exemplary approaches to the acceleration of projectiles are provided. Both approaches can utilize concepts associated with the Inductrack maglev system. Either of them provides an effective means of accelerating multi-kilogram projectiles to velocities of several kilometers per second, using launchers of order 10 meters in length, thus enabling the acceleration of projectiles to high velocities by electromagnetic forces.

  16. Bite through the tent.

    Science.gov (United States)

    Naue, Jana; Lutz-Bonengel, Sabine; Pietsch, Klaus; Sänger, Timo; Schlauderer, Nicola; Schmidt, Ulrike

    2012-05-01

    The authors report on a young boy who was bitten into his face by an unknown animal while being asleep in a tent. Given the bite marks and the location of the scene, members of the mustelidae and canidae families were the first "suspects." Deoxyribunucleic acid (DNA) recovered from the tent's wall was analyzed with regard to parts of the mitochondrial 12S ribosomal ribunucleic acid (12S rRNA) and cytochrome b (cytb) genes as well as nuclear short tandem repeats (STRs). Since Sanger sequencing revealed a mixed sequence with a strong human component overlying the nonhuman contributor, an animal screening using a duplex real-time polymerase chain reaction (PCR) with an intercalating dye and melt curve analysis was employed. The results were later confirmed by cloning. The applied commercial canine STR kit verified the animal family (canidae) but did not help in discriminating the species due to cross-species amplification. In the presented case, the real-time PCR assay offered the cheapest and fastest method for animal family determination, which then allowed for an appropriate and sample-saving strategy to characterize the causative animal species.

  17. [Snake bite injuries].

    Science.gov (United States)

    Turchányi, B; Szalontay, T; Zacher, G

    2000-05-14

    Authors treated five patients who suffered venomous snake-bite injury. Although these snakes are not native in Hungary, this kind of injury is estimated to be more frequent, because of the increasing number of the private collections and illegal import of these reptiles. The local and general symptoms, the therapeutic steps are summarised in this study considering the literature as well. Two patients did not show any systemic or local symptoms at the level of injury, they needed only short observation, and woundcare. The other three patients had serious transient systematic symptoms (vasolability, hypotension/shock, coagulopathy, confusion). Two of them were given specific antivenom. As the third patient did not agree with the serum therapy, plasmapheresis was the choice to treat him, and it seemed to be effective. Few hours later the patients needed surgery because of serious compartment syndrome of their affected upper extremity. Surgical decompression of all the compartments and different possibilities of the secondary skin closure technique are demonstrated. Two patient healed completely, but the right thumb of the third was lost. Authors summarise the effects of the poisons, the symptoms, and the basic therapeutic steps during the first aid and in the primary hospital phase, respectively. They point out the indications of the serum therapy and the correct surgical decompression of the injured extremity.

  18. Describing the relationship between cat bites and human depression using data from an electronic health record.

    Directory of Open Access Journals (Sweden)

    David A Hanauer

    Full Text Available Data mining approaches have been increasingly applied to the electronic health record and have led to the discovery of numerous clinical associations. Recent data mining studies have suggested a potential association between cat bites and human depression. To explore this possible association in more detail we first used administrative diagnosis codes to identify patients with either depression or bites, drawn from a population of 1.3 million patients. We then conducted a manual chart review in the electronic health record of all patients with a code for a bite to accurately determine which were from cats or dogs. Overall there were 750 patients with cat bites, 1,108 with dog bites, and approximately 117,000 patients with depression. Depression was found in 41.3% of patients with cat bites and 28.7% of those with dog bites. Furthermore, 85.5% of those with both cat bites and depression were women, compared to 64.5% of those with dog bites and depression. The probability of a woman being diagnosed with depression at some point in her life if she presented to our health system with a cat bite was 47.0%, compared to 24.2% of men presenting with a similar bite. The high proportion of depression in patients who had cat bites, especially among women, suggests that screening for depression could be appropriate in patients who present to a clinical provider with a cat bite. Additionally, while no causative link is known to explain this association, there is growing evidence to suggest that the relationship between cats and human mental illness, such as depression, warrants further investigation.

  19. Effects of bite raising and occlusal awareness on tongue thrust in untreated children.

    Science.gov (United States)

    Dahan, José S; Lelong, Odette

    2003-08-01

    The purpose of this study was to determine the influence of conscious bite (occlusal awareness), with or without immediate bite raising, on tongue thrust during swallowing and speech. A total of 110 untreated children (age range, 7-12 years; mean, 9 years 8 months) were examined with various extraoral and intraoral observation tests. Subjects were divided according to sex and score on the labiolingual dysfunction index (LLDI) into high (LLDI-H) and weak (LLDI-W) dysfunction groups. A special, previously tested chocolate paste was used to map tongue and tooth contacts during task performance, including conscious bite (occlusal awareness) with and without bite raising. The bite was raised with an overlay or provisional occlusal plane placed unilaterally on the maxillary right molar. The results did not show any difference between boys and girls, but other findings were related to the LLDI score. Habitual mouth closure and swallowing without the provisional occlusal plane produced less pronounced bite contact in the LLDI-H group. Swallowing with conscious bite increased the bite contact in both groups but predominantly in the LLDI-H group. Tongue thrust reacted inversely to bite contacts: it was reduced when occlusion was perceived with and without bite raise but somewhat more with the provisional occlusal plane. The LLDI-W group was less affected. Tongue thrust was inhibited in both groups during speaking with bite raising and occlusal awareness. These results indicate that conscious bite helps to control the tongue. Slight raising of the bite increases occlusal awareness and its inhibiting effect on tongue thrust. A provisional occlusal plane or a similar overlay might be a useful adjunct in training the tongue to retrude in subjects with oral dysfunction.

  20. Period Prevalence of Acute Neck Injury in US Air Force Pilots Exposed to High G Forces

    Science.gov (United States)

    1986-06-01

    unquantified clinical and epidemiological problem in exposed pilots. There has been a paucity of research in this area. This proposal is a beginning, with a...larg-e majority of pilots. Thus neck injury and its sequelae are unquantified clinical and epidemiological problems in pilots exposed to high G forces...Basal Impression 19. Cervical Ribs 20. Scoliosis , 21. Intraspongy Nuclear Hernitation 22. Significant Compression or Loss of Height of Any Vertebral

  1. High-Resolution Force Balance Analyses of Tidewater Glacier Dynamics

    Science.gov (United States)

    Enderlin, E. M.; Hamilton, G. S.; O'Neel, S.

    2015-12-01

    Changes in glacier velocity, thickness, and terminus position have been used to infer the dynamic response of tidewater glaciers to environmental perturbations, yet few analyses have attempted to quantify the associated variations in the glacier force balance. Where repeat high-resolution ice thickness and velocity estimates are available, force balance time series can be constructed to investigate the redistribution of driving and resistive forces associated with changes in terminus position. Comparative force balance analyses may, therefore, help us understand the variable dynamic response observed for glaciers in close proximity to each other. Here we construct force balance time series for Helheim Glacier, SE Greenland, and Columbia Glacier, SE Alaska, to investigate differences in dynamic sensitivity to terminus position change. The analysis relies on in situ and remotely sensed observations of ice thickness, velocity, and terminus position. Ice thickness time series are obtained from stereo satellite image-derived surface elevation and continuity-derived bed elevations that are constrained by airborne radar observations. Surface velocity time series are obtained from interferometric synthetic aperture radar (InSAR) observations. Approximately daily terminus positions are from a combination of satellite images and terrestrial time-lapse photographs. Helheim and Columbia glaciers are two of the best-studied Arctic tidewater glaciers with comprehensive high-resolution observational time series, yet we find that bed elevation uncertainties and poorly-constrained stress-coupling length estimates still hinder the analysis of spatial and temporal force balance variations. Here we use a new observationally-based method to estimate the stress-coupling length which successfully reduces noise in the derived force balance but preserves spatial variations that can be over-smoothed when estimating the stress-coupling length as a scalar function of the ice thickness

  2. High-resolution friction force microscopy under electrochemical control

    Science.gov (United States)

    Labuda, Aleksander; Paul, William; Pietrobon, Brendan; Lennox, R. Bruce; Grütter, Peter H.; Bennewitz, Roland

    2010-08-01

    We report the design and development of a friction force microscope for high-resolution studies in electrochemical environments. The design choices are motivated by the experimental requirements of atomic-scale friction measurements in liquids. The noise of the system is analyzed based on a methodology for the quantification of all the noise sources. The quantitative contribution of each noise source is analyzed in a series of lateral force measurements. Normal force detection is demonstrated in a study of the solvation potential in a confined liquid, octamethylcyclotetrasiloxane. The limitations of the timing resolution of the instrument are discussed in the context of an atomic stick-slip measurement. The instrument is capable of studying the atomic friction contrast between a bare Au(111) surface and a copper monolayer deposited at underpotential conditions in perchloric acid.

  3. High-Force Dielectric Electroactive Polymer (DEAP) membrane actuator

    Science.gov (United States)

    Hau, Steffen; York, Alexander; Seelecke, Stefan

    2016-04-01

    Energy efficiency, lightweight and scalability are key features for actuators in applications such as valves, pumps or any portable system. Dielectric electroactive Polymer (DEAP) technology is able to fulfill these requirements1 better than commonly used technology e.g. solenoids, but has limitations concerning force and stroke. However, the circular DEAP membrane actuator shows a potential increase in stroke in the mm range, when combined with an appropriate biasing mechanism2. Although, thus far, their force range is limited to the single-digit Newton range, or less3,4. This work describes how this force limit of DEAP membrane actuators can be pushed to the high double-digit Newton range and beyond. The concept for such an actuator consists of a stack of double-layered DEAPs membrane actuator combined with a biasing mechanism. These two components are combined in a novel way, which allows a compact design by integrating the biasing mechanism into the DEAP membrane actuator stack. Subsequently, the single components are manufactured, tested, and their force-displacement characteristic is documented. Utilizing this data allows assembling them into actuator systems for different applications. Two different actuators are assembled and tested (dimensions: 85x85x30mm3 (LxWxH)). The first one is able to lift 7.5kg. The second one can generate a force of 66N while acting against a spring load.

  4. 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

  5. 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 ...

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

    Science.gov (United States)

    Ren, Juan; Zou, Qingze

    2014-07-01

    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.

  7. High resolution atomic force microscopy of double-stranded RNA

    Science.gov (United States)

    Ares, Pablo; Fuentes-Perez, Maria Eugenia; Herrero-Galán, Elías; Valpuesta, José M.; Gil, Adriana; Gomez-Herrero, Julio; Moreno-Herrero, Fernando

    2016-06-01

    Double-stranded (ds) RNA mediates the suppression of specific gene expression, it is the genetic material of a number of viruses, and a key activator of the innate immune response against viral infections. The ever increasing list of roles played by dsRNA in the cell and its potential biotechnological applications over the last decade has raised an interest for the characterization of its mechanical properties and structure, and that includes approaches using Atomic Force Microscopy (AFM) and other single-molecule techniques. Recent reports have resolved the structure of dsDNA with AFM at unprecedented resolution. However, an equivalent study with dsRNA is still lacking. Here, we have visualized the double helix of dsRNA under near-physiological conditions and at sufficient resolution to resolve the A-form sub-helical pitch periodicity. We have employed different high-sensitive force-detection methods and obtained images with similar spatial resolution. Therefore, we show here that the limiting factors for high-resolution AFM imaging of soft materials in liquid medium are, rather than the imaging mode, the force between the tip and the sample and the sharpness of the tip apex.Double-stranded (ds) RNA mediates the suppression of specific gene expression, it is the genetic material of a number of viruses, and a key activator of the innate immune response against viral infections. The ever increasing list of roles played by dsRNA in the cell and its potential biotechnological applications over the last decade has raised an interest for the characterization of its mechanical properties and structure, and that includes approaches using Atomic Force Microscopy (AFM) and other single-molecule techniques. Recent reports have resolved the structure of dsDNA with AFM at unprecedented resolution. However, an equivalent study with dsRNA is still lacking. Here, we have visualized the double helix of dsRNA under near-physiological conditions and at sufficient resolution to

  8. Nuclear Forces and High-Performance Computing: The Perfect Match

    Energy Technology Data Exchange (ETDEWEB)

    Luu, T; Walker-Loud, A

    2009-06-12

    High-performance computing is now enabling the calculation of certain nuclear 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. We briefly describe the state of the field and describe how progress in this field will impact the greater nuclear physics community. We give estimates of computational requirements needed to obtain certain milestones and describe the scientific and computational challenges of this field.

  9. 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...

  10. Heridas por Mordedura / Bites Injuries

    Directory of Open Access Journals (Sweden)

    Coturel A

    2015-11-01

    Full Text Available Injuries for animal bites are a common cause of consultation to emergency services. However there are still controversies about some aspects of their treatment. It is not recommended to brush the wound area but to flush the surface with isoosmolar saline. The primary wound closure is justified when improves the cosmetic outcome and has no increase risk of infection. Antibiotic prophylaxis is allways indicated in cats or humans bites. The drug of choice is amoxicillin clavulanate.The tetanus vaccine should be indicated when the patient has not full vaccination scheme and rabies vaccine in cases of suspected or confirmed infected animals.

  11. [Compartment syndrome following adder bites].

    Science.gov (United States)

    Roed, Casper; Bayer, Lasse; Lebech, Anne-Mette Kjaer; Poulsen, Jesper Brøndum; Katzenstein, Terese

    2009-01-26

    Bites from the adder, Vipera Berus, can have serious clinical consequences due to systemic effects. Meanwhile, the local swelling calls for attention as well. Two cases of seven- and eleven-year-old boys are reported. The first patient was bitten in the 5th toe, the second in the thumb. Both developed fasciotomy-requiring compartment syndrome of the lower and upper limb, respectively. Recognition of this most seldom complication of an adder bite is vital to save the limb. We recommend that the classical signs and symptoms of compartment syndrome serve as indication for surgery. However, compartment pressure measurement can be helpful in the assessment of children.

  12. 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.

  13. Casimir force between δ -δ' mirrors transparent at high frequencies

    Science.gov (United States)

    Braga, Alessandra N.; Silva, Jeferson Danilo L.; Alves, Danilo T.

    2016-12-01

    We investigate, in the context of a real massless scalar field in 1 +1 dimensions, models of partially reflecting mirrors simulated by Dirac δ -δ' point interactions. In the literature, these models do not exhibit full transparency at high frequencies. In order to provide a more realistic feature for these models, we propose a modified δ -δ' point interaction that enables full transparency in the limit of high frequencies. Taking this modified δ -δ' model into account, we investigate the Casimir force, comparing our results with those found in the literature.

  14. Bites and Scratches (For Parents)

    Science.gov (United States)

    ... small. A child who is bitten by an animal may need antibiotics, a tetanus booster, or rarely, a series of rabies shots. A bite or scratch on a child's face, hand, or foot is ... unfamiliar or wild animal, note the location of the animal. Some animals ...

  15. [Viper (Vipera berus) snake bites].

    Science.gov (United States)

    Valenta, J; Kornalík, F

    2000-07-19

    Cases of snake bites (Vipera berus) have as compared with past years a rising trend in the Czech Republic. This ensues among other factors from a higher prevalence of snakes due to the improving ecological situation. The morbidity of snake bites is of no epidemiological importance, the frequency of snake bites amounts to several tens per year and in some clinically manifest intoxication does not develop. Nevertheless in individual cases, in children weakened subjects, a viper bite may be manifested by a serious and in exceptional instances fatal affection. Within the framework of first aid the authors do not recommend application of a tourniquet or dissecting of the wound because of undesirable potentiation of tissue traumatization. Non-specific treatment involves the administration of corticoids and antihistaminics. Specific immunotherapy, administration of horse antiserum (Ipser Europe, Pasteur Mérieux, France) is indicated only in case of systemic or very severe local symptoms and is associated with the risk of a severe allergic reaction. In case of severe systemic symptoms, symptomatic treatment in a health institution of the appropriate type is of fundamental importance. In all cases observation of the affected subject is recommended to rule out intoxication or the development of possible complications.

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

    Science.gov (United States)

    Toyjanova, Jennet; Bar-Kochba, Eyal; López-Fagundo, Cristina; Reichner, Jonathan; Hoffman-Kim, Diane; Franck, Christian

    2014-01-01

    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.

  17. 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.

  18. 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

  19. Segmental Orthodontics for the Correction of Cross Bites

    Science.gov (United States)

    Mathur, Rinku

    2011-01-01

    ABSTRACT Cross bite is a condition where one or more teeth may be abnormally malposed buccally or lingually or labially with reference to the opposing tooth or teeth. Cross bite correction is highly recommended as this kind of malocclusion do not diminish with age. Uncorrected cross bite may lead to abnormal wear of lower anteriors and cuspal interference, mandibular shift resulting in mandibular asymmetry and temporomandibular joint dysfunction syndrome. There are several methods for treating this type of malocclusion. In this article, segmental orthodontics has been highlighted by using 2 × 4 appliance therapy and lingual button with cross elastics. This appliance offers many advantages as it provides complete control of anterior tooth position, is extremely well tolerated, requires no adjustment by the patient and allows accurate and rapid positioning of teeth. PMID:27616858

  20. 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.

  1. High resolution magnetic imaging: MicroSQUID Force Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hasselbach, K; Ladam, C; Dolocan, V O; Hykel, D; Crozes, T [Institut Neel, CNRS et Universite Joseph Fourier, BP 166, F-38042 Grenoble Cedex 9 (France); Schuster, K [Institut de RadioAstronomie Millimetrique 300 rue de la Piscine, Domaine Universitaire F-38406 Saint Martin d' Heres (France); Mailly, D [Laboratoire de Photonique et de Nanostructures, CNRS, Site Alcatel de Marcoussis Route de Nozay F-91460 Marcoussis (France)], E-mail: klaus.hasselbach@grenoble.cnrs.fr

    2008-02-01

    Magnetic imaging at the micrometer scale with high sensitivity is a challenge difficult to be met. Magnetic force microscopy has a very high spatial resolution but is limited in magnetic resolution. Hall probe microscopy is very powerful but sensor fabrication at the one micron scale is difficult and effects due to discreteness of charge appear in the form of significant 1/f noise. SQUID microscopy is very powerful, having high magnetic resolution, but spatial resolution is usually of the order of 10 {mu}m. The difficulties lay mostly in an efficient way to couple flux to the sensor. The only way to improve spatial resolution is to place the probe close to the very edge of the support, thus maximising coupling and spatial resolution. If there has been found a way to bring close the tip, there must be also found a reliable a way to maintain distance during scanning. We want to present recent improvements on scanning microsquid microscopy: Namely the improved fabrication of microSQUID tips using silicon micro machining and the precise positioning of the micrometer diameter microSQUID loop by electron beam lithography. The microSQUID is a microbridge DC SQUID, with two opposite microbridges. The constrictions are patterned by high-resolution e-beam lithography and have a width of 20 nm and a length of about 100 nm. The distance control during scanning is obtained by integrating the microSQUID sensor with a piezoelectric tuning fork acting as a force sensor allowing to control height and even topographic imaging. The detector is placed in a custom built near field microscope and the sample temperature can be varied between 0.1 Kelvin and 10 K. The microscope is used to study magnetic flux structures in unconventional superconductors and will be used to observe thermal domains in superconducting detectors in the voltage state.

  2. Contributions of facial morphology, age, and gender to EMG activity under biting and resting conditions: a canonical correlation analysis.

    Science.gov (United States)

    Fogle, L L; Glaros, A G

    1995-08-01

    Theoretical studies suggest that facial morphology may confer a mechanical advantage to particular individuals during force production, but not during rest. However, prior studies on the relationship between facial morphology and EMG suffer from various methodological limitations. We examined the hypothesis that facial morphology variables contribute significantly and meaningfully to the variance in masticatory muscle EMG when subjects produce specific levels of interocclusal force, but not when subjects are at rest. Measures of facial morphology included gonial angle, ramus height, and maxillary height, as determined from lateral cephalograms. EMG data were obtained from surface electrodes placed on masseter and temporalis sites. Subjects (N = 96) sat in a darkened, sound-attenuated room while they watched a seven-minute segment of a movie. EMG activity obtained during the last two minutes was used as a baseline period. Using the central incisors, subjects then provided five different force levels ranging from 6.5 to 48 lb in random order on a bite-force device while EMG data were collected. A canonical correlation analysis, performed on the set of predictor variables (age, gender, and facial morphology measurements) and the set of criterion variables (EMG data), showed a significant canonical correlation between the two variable sets while biting, but not at rest. Age, but not the facial morphology variables, was highly related to the canonical variate.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Measurement of Metal Cutting Forces at High Speeds

    Science.gov (United States)

    Princehouse, David W.

    1996-03-01

    Proposed numerically-controlled milling machines will cut aluminum alloys with cutter tip speeds of up to 130 m/s (300 MPH). There are a variety of challenging technical problems to be solved--high power density motors, inverters, cutter/machine dynamics, servo control systems--and compelling reasons to do so. We measured time-varying cutting forces at these tip speeds with a 25.4-cm (10-in) diameter cutter turning at rates up to 167 Hz (10,000 RPM.) We took special care to measure and compensate for the dynamic response of the force transducer (a three-axis quartz-crystal milling dynamometer), extending the useful bandwidth of the measurements well into the mechanical resonances of the dynamometer. We instrumented a production milling machine on the factory floor and processed megabytes of data, obtaining results minutes after a cut was made. This case study shows how a physicist's background in mechanics, instrumentation, signal processing, and computing hardware and software can help advance the state of the art in aerospace manufacturing.

  4. Necrotizing fasciitis due to Streptococcus mitis caused by accidental human bite.

    Science.gov (United States)

    Bastug, Aliye; Kislak, Sumeyye; Mutlu, Nevzat Mehmet; Akcaboy, Zeynep Nur; Koksal, Asude; Sertcelik, Ahmet; Ünlü, Ramazan Erkin; Akinci, Esragul; Bodur, Hurrem

    2016-01-31

    Human bite wounds are more prone to infection than animal bites, which may cause necrotizing soft tissue infections such as myositis, fasciitis. Both aerobic and anaerobic microorganisms may be responsible, including Streptococcus spp., Staphylococcus aureus, Peptostreptococcus spp. Necrotizing fasciitis is characterized by serious tissue destruction and systemic toxicity with high morbidity and mortality. We report a patient with Streptococcus mitis associated necrotizing fasciitis on the upper extremity resulting from an accidental human bite, which caused nearly fatal infection. Prophylactic antibiotic treatment should be given after a human bite to prevent infection. If the infection signs and symptoms develop, rapid diagnosis, appropriate antibiotic and surgical therapy should be administered immediately. Streptococcus mitis is a viridans streptococcus, usually known as a relatively benign oral streptococcus. To our knowledge, this is the first necrotizing fasciitis case due to Streptococcus mitis after human bite.

  5. Quadrature phase interferometer for high resolution force spectroscopy

    CERN Document Server

    Paolino, Pierdomenico; Bellon, Ludovic

    2013-01-01

    In this article, we present a deflection measurement setup for Atomic Force Microscopy (AFM). It is based on a quadrature phase differential interferometer: we measure the optical path difference between a laser beam reflecting above the cantilever tip and a reference beam reflecting on the static base of the sensor. A design with very low environmental susceptibility and another allowing calibrated measurements on a wide spectral range are described. Both enable a very high resolution (down to $2.5E-15 m/sqrt{Hz}$), illustrated by a thermal noise measurement on an AFM cantilever. A quick review shows that our precision is equaling or outperforming the best results reported in the literature, but for a much larger deflection range, up to a few microns.

  6. Schmallenberg virus in Culicoides spp. biting midges, the Netherlands, 2011

    NARCIS (Netherlands)

    Elbers, A.R.W.; Meiswinkel, R.; Weezep, van E.; Sloet van Oldruitenborgh-Oosterbaan, M.M.; Kooi, E.A.

    2013-01-01

    To determine which species of Culicoides biting midges carry Schmallenberg virus (SBV), we assayed midges collected in the Netherlands during autumn 2011. SBV RNA was found in C. scoticus, C. obsoletus sensu stricto, and C. chiopterus. The high proportion of infected midges might explain the rapid

  7. Swiss prospective study on spider bites.

    Science.gov (United States)

    Gnädinger, Markus; Nentwig, Wolfgang; Fuchs, Joan; Ceschi, Alessandro

    2013-09-04

    Knowledge of spider bites in Central Europe derives mainly from anecdotal case presentations; therefore we aimed to collect cases systematically. From June 2011 to November 2012 we prospectively collected 17 cases of alleged spider bites, and together with two spontaneous notifications later on, our database totaled 19 cases. Among them, eight cases could be verified. The causative species were: Cheiracanthium punctorium (3), Zoropsis spinimana (2), Amaurobius ferox, Tegenaria atrica and Malthonica ferruginea (1 each). Clinical presentation was generally mild, with the exception of Cheiracanthium punctorium, and patients recovered fully without sequelae. In Switzerland, spider bites generally have a benign clinical course, which is characterised by minor effects, with rapid and complete recovery. Since only verified spider bites can be regarded as spider bites, in the case of clinically important arachnidism, the spider should be sent to an expert for identification. Our study may help to diminish spider fear and reassure people who have experienced a bite.

  8. 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.

  9. Miniature High-Force, Long-Stroke SMA Linear Actuators

    Science.gov (United States)

    Cummin, Mark A.; Donakowski, William; Cohen, Howard

    2008-01-01

    Improved long-stroke shape-memory-alloy (SMA) linear actuators are being developed to exert significantly higher forces and operate at higher activation temperatures than do prior SMA actuators. In these actuators, long linear strokes are achieved through the principle of displacement multiplication, according to which there are multiple stages, each intermediate stage being connected by straight SMA wire segments to the next stage so that relative motions of stages are additive toward the final stage, which is the output stage. Prior SMA actuators typically include polymer housings or shells, steel or aluminum stages, and polymer pads between successive stages of displacement-multiplication assemblies. Typical output forces of prior SMA actuators range from 10 to 20 N, and typical strokes range from 0.5 to 1.5 cm. An important disadvantage of prior SMA wire actuators is relatively low cycle speed, which is related to actuation temperature as follows: The SMA wires in prior SMA actuators are typically made of a durable nickel/titanium alloy that has a shape-memory activation temperature of 80 C. An SMA wire can be heated quickly from below to above its activation temperature to obtain a stroke in one direction, but must then be allowed to cool to somewhat below its activation temperature (typically, less than or equal to 60 C in the case of an activation temperature of 80 C) to obtain a stroke in the opposite direction (return stroke). At typical ambient temperatures, cooling times are of the order of several seconds. Cooling times thus limit cycle speeds. Wires made of SMA alloys having significantly higher activation temperatures [denoted ultra-high-temperature (UHT) SMA alloys] cool to the required lower return-stroke temperatures more rapidly, making it possible to increase cycle speeds. The present development is motivated by a need, in some applications (especially aeronautical and space-flight applications) for SMA actuators that exert higher forces, operate

  10. The Properties of Light Pressure Force with High Order in Laser Fields

    Institute of Scientific and Technical Information of China (English)

    陈险峰; 方建兴; 朱士群

    2002-01-01

    In this paper, the light pressure force in low and high intensity laser fields is derived. The exact numerical results of forces Fn∥(n=0,1,2,3,4,5,6…) through the matrix continued fraction method are presented. At low intensity field (G=1), the spatially averaged force F0∥ gives a cooling effect at the negative detuning. At high intensity (G=64), the effects of the forces with higher order (n≥2) appear and the contributes of the forces with odd or even order are opposite. It is great different from no high order force at low intensity.

  11. 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

  12. 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 sin

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

    Medline Plus

    Full Text Available ... de12", ]; for (var c = 0; c Tips to prevent and treat bug bites Although most bug bites ... take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the following tips: Use ...

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

    Medline Plus

    Full Text Available ... de12", ]; for (var c = 0; c Tips to prevent and treat bug bites Although most bug bites ... take steps to reduce your risk. To help prevent bug bites, dermatologists recommend the following tips: Use ...

  15. Response of thermosphere density to high-latitude forcing

    Science.gov (United States)

    Yamazaki, Y.; Kosch, M. J.; Vickers, H.; Sutton, E. K.; Ogawa, Y.

    2014-12-01

    Solar wind-magnetospheric disturbances cause enhancements in the energy input to the high-latitude upper atmosphere through particle precipitation and Joule heating. As the upper atmosphere is heated and expanded during geomagnetically disturbed periods, the neutral density in the thermosphere increases at a fixed altitude. Conversely, the thermosphere contracts during the recovery phase of the disturbance, resulting in a decrease of the density. The main objectives of this study are (1) to determine the morphology of the global thermospheric density response to high-latitude forcing, and (2) to determine the recovery speed of the thermosphere density after geomagnetic disturbances. For (1), we use thermospheric density data measured by the Challenging Minisatellite Payload (CHAMP) satellite during 2000-2010. It is demonstrated that the density enhancement during disturbed periods occurs first in the dayside cusp region, and the density at other regions slowly follows it. The reverse process is observed when geomagnetic activity ceases; the density enhancement in the cusp region fades away first, then the global density slowly goes back to the quiet level. For (2), we analyze EISCAT Svalbard radar and Tromso UHF radar data to estimate thermospheric densities during the recovery phase of geomagnetic disturbances. We attempt to determine the time constant for the density recovery both inside and outside the cusp region.

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

    Science.gov (United States)

    2016-07-27

    Forcing in a High Pressure Environment 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Mario Roa, S. Alex Schumaker...disclose the work. PA Clearance Number: 16308 Clearance Date: 6/17/2016 13. SUPPLEMENTARY NOTES For presentation at AIAA Propulsion and Energy; Salt...the coupling between the impact waves created by impinging jets and high frequency acoustic pressure perturbations. High speed, backlit imaging was

  17. 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

  18. 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…

  19. 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.

  20. Animal Bites Epidemiology in Shahroud City

    Directory of Open Access Journals (Sweden)

    Mohammad Amiri

    Full Text Available Introduction: Rabies is an infectious central nervous system disease that infects all mammals and man. This study aimed at investigating the epidemiology of animal bites in Shahroud. Methods: In this deh1ive study all the data related to animal bite cases in shahroud in 2008-2009 were collected based on the data registration notebooks. Results: A total of 588 cases of animal bite were reported in 2008-2009 the majority of whom (82.1% were male. Of this total 35.7% were urban and 64.3% were rural. Just 2 of the cases were foreigners. The incidence rate of animal bite in the city was 159 (27% compared to 429 cases (73% in villages. Dogs and cats accounted for about 79.1% and 12.6% of the cases respectively. 12 cases were also wolf fox and Reynard bites. All cases have completed vaccination. In 82.3% of animal bites the biter was alive after 10 days and in 2% biters were dead and in 15.6% the biter reported invisible after 10 days. The incidence rate of animal bites in Shahroud was 246 in one hundred thousand. Conclusions: Animal bites are one of the most important problems of public health. Educational activities along with the promotion of out- organizing cooperation can play a significant role in controlling this problem

  1. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Replace the nail-biting habit with a good habit: When you feel like biting your nails, try playing with a stress ball or silly putty instead. This will help keep your hands busy and away from your mouth. Identify your triggers: These could be physical triggers, ...

  2. The differential effect of metabolic alkalosis on maximum force and rate of force development during repeated, high-intensity cycling.

    Science.gov (United States)

    Siegler, Jason C; Marshall, Paul W M; Raftry, Sean; Brooks, Cristy; Dowswell, Ben; Romero, Rick; Green, Simon

    2013-12-01

    The purpose of this investigation was to assess the influence of sodium bicarbonate supplementation on maximal force production, rate of force development (RFD), and muscle recruitment during repeated bouts of high-intensity cycling. Ten male and female (n = 10) subjects completed two fixed-cadence, high-intensity cycling trials. Each trial consisted of a series of 30-s efforts at 120% peak power output (maximum graded test) that were interspersed with 30-s recovery periods until task failure. Prior to each trial, subjects consumed 0.3 g/kg sodium bicarbonate (ALK) or placebo (PLA). Maximal voluntary contractions were performed immediately after each 30-s effort. Maximal force (F max) was calculated as the greatest force recorded over a 25-ms period throughout the entire contraction duration while maximal RFD (RFD max) was calculated as the greatest 10-ms average slope throughout that same contraction. F max declined similarly in both the ALK and PLA conditions, with baseline values (ALK: 1,226 ± 393 N; PLA: 1,222 ± 369 N) declining nearly 295 ± 54 N [95% confidence interval (CI) = 84-508 N; P force vs. maximum rate of force development during a whole body fatiguing task.

  3. 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

  4. Ion drag force in plasmas at high electronegativity.

    Science.gov (United States)

    Denysenko, I; Yu, M Y; Stenflo, L; Xu, S

    2005-07-01

    The electric as well as the positive- and negative-ion drag forces on an isolated dust grain in an electronegative plasma are studied for large negative-ion densities, when the negative ions are not Boltzmann distributed. The investigation is carried out for submicrometer dust particles, so that the theory of Coulomb scattering is applicable for describing ion-dust interaction. Among the forces acting on the dust grain, the negative-ion drag force is found to be important. The effects of the negative-ion density, neutral-gas pressure, and dust-grain size on the forces are also considered. It is shown that by increasing the density of the negative ions one can effectively manipulate the dust grains. Our results imply that both dust voids and balls can be formed.

  5. 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.

  6. Brodie bite with an extracted mandibular first molar in a young adult: a case report.

    Science.gov (United States)

    Chugh, Vinay K; Sharma, Vijay P; Tandon, Pradeep; Singh, Gyan P

    2010-05-01

    Total buccal crossbites are rare, but, when they occur, they can be extremely difficult to correct, even with surgery and orthodontics. In most patients with in-locking crossbites, the maxillary teeth erupt past their mandibular antagonists, creating severe occlusal difficulties. This article presents an adult patient with scissors-bite or partial telescoping bite bilaterally in the posterior region and an extracted mandibular first molar on the right side. She was treated with expansion of the mandibular arch, and the subsequent open bite was closed with the help of masticatory muscle exercises and high-pull headgear. The second and third molars were uprighted and moved mesially to close the extraction spaces.

  7. Precipitation-Strengthened, High-Temperature, High-Force Shape Memory Alloys

    Science.gov (United States)

    Noebe, Ronald D.; Draper, Susan L.; Nathal, Michael V.; Crombie, Edwin A.

    2008-01-01

    Shape memory alloys (SMAs) are an enabling component in the development of compact, lightweight, durable, high-force actuation systems particularly for use where hydraulics or electrical motors are not practical. However, commercial shape memory alloys based on NiTi are only suitable for applications near room temperature, due to their relatively low transformation temperatures, while many potential applications require higher temperature capability. Consequently, a family of (Ni,Pt)(sub 1-x)Ti(sub x) shape memory alloys with Ti concentrations ranging from about 15 to 25 at.% have been developed for applications in which there are requirements for SMA actuators to exert high forces at operating temperatures higher than those of conventional binary NiTi SMAs. These alloys can be heat treated in the range of 500 C to produce a series of fine precipitate phases that increase the strength of alloy while maintaining a high transformation temperature, even in Ti-lean compositions.

  8. Fundamental High-Speed Limits in Single-Molecule, Single-Cell, and Nanoscale Force Spectroscopies

    Science.gov (United States)

    2016-01-01

    Force spectroscopy is enhancing our understanding of single-biomolecule, single-cell, and nanoscale mechanics. Force spectroscopy postulates the proportionality between the interaction force and the instantaneous probe deflection. By studying the probe dynamics, we demonstrate that the total force acting on the probe has three different components: the interaction, the hydrodynamic, and the inertial. The amplitudes of those components depend on the ratio between the resonant frequency and the frequency at which the data are measured. A force–distance curve provides a faithful measurement of the interaction force between two molecules when the inertial and hydrodynamic components are negligible. Otherwise, force spectroscopy measurements will underestimate the value of unbinding forces. Neglecting the above force components requires the use of frequency ratios in the 50–500 range. These ratios will limit the use of high-speed methods in force spectroscopy. The theory is supported by numerical simulations. PMID:27359243

  9. 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.

  10. Australian wolf spider bites (Lycosidae): clinical effects and influence of species on bite circumstances.

    Science.gov (United States)

    Isbister, Geoffrey K; Framenau, Volker W

    2004-01-01

    Necrotic arachnidism continues to be attributed to wolf spider bites. This study investigates the clinical effects of bites by wolf spiders in Australia (family Lycosidae). Subjects were recruited prospectively from February 1999 to April 2001 from participating emergency departments or state poison information centers. Subjects were included if they had a definite bite by a wolf spider and had collected the spider, which was later identified by an arachnologist. Spiders were identified to the lowest taxonomic level possible and cephalothorax width was measured to correlate bite effects and spider size. There were 45 definite wolf spider bites (23 male and 22 female patients; age range 1 to 69 years, median age 28 years). Species level identifications (14 species) were possible for 31 of 43 spiders belonging to seven different generic groupings. Most bites were by spiders from four generic groupings, Tasmanicosa (including 'Lycosa') (15), Venatrix (8), Venator (10), and Hogna (7). Bites occurred more commonly in south-eastern Australia and occurred throughout the year, with 7 bites (16%) in late autumn or winter. In 7 cases (16%) the person was swimming in or cleaning a pool. Seventy-two percent of bites occurred on distal parts of limbs. Pain occurred in all bites and was severe in 11 cases (24%), with a median duration of 10 min (IQR: 2-60 min). Other effects included puncture marks/bleeding (33%), swelling (20%), redness (67%), and itchiness (13%). Minor systemic effects occurred in three patients (7%): nausea (two), headache (one) and malaise (one). There were no cases of necrotic ulcers [0%; 97.5% CI 0-8%]. Tasmanicosa spider bites caused significantly more itchiness and redness, and large spiders (>5 mm) more often caused severe pain and left fang marks. Wolf spider bites cause minor effects, no more severe than most other spiders, and do not appear to cause necrotic ulcers. The effects are likely to be due to mechanical injury, although minor local

  11. New linear piezomotors for high-force precise positioning applications

    Science.gov (United States)

    Le Letty, Ronan; Claeyssen, Frank; Barillot, Francois; Six, Marc F.; Bouchilloux, Philippe

    1998-07-01

    Piezomotors are an increasingly competitive alternative to electromagnetic stepper motors, especially in applications where large bandwidths and/or precise positioning control are desired. Piezomotors use a combination of electromechanical and frictional forces and, compared to conventional electromagnetic motors, have the advantages that no power supply is required to maintain the motor in position and no lubrication is necessary in the device. The operating principle of these motors relies on the use of an ultrasonic vibration, which is created via the piezoelectric effect (at resonance in most cases), in order to generate vibration forces at the `stator/rotor' contact interface. A mechanical preload is also applied at this contact interface and is responsible for the motor's holding force at rest. To meet the specifications of an aerospace application, we developed a new design of Linear PiezoMotors (LPMs). The first prototype we built shows very promising results, and makes the LPM a serious candidate to replace conventional stepper motors. The LPM features the following characteristics: a standing force of 100 N, a blocked force of 37 N, a maximum actuation speed of 23 mm/s, a maximum run of 10 mm, a mass of 500 g, an electrical power of 2.2 W, and a position accuracy superior to 1 micrometers . To our knowledge, the driving force delivered by the LPM has never before been achieved in resonant devices. This paper describes the physical operating principles of the LPM, as well as the modeling tools and experimental techniques we used for its development. Several implementation schemes are also presented and show the wide range of possible applications offered by the linear piezomotor.

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

    Science.gov (United States)

    2016-07-27

    other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a ...Transverse Acoustic Forcing in a High Pressure Environment 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Mario...Briefing Charts 15. SUBJECT TERMS N/ A 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE

  13. Susceptibility to Frost-Bite

    Directory of Open Access Journals (Sweden)

    Bal Krishna

    1966-11-01

    Full Text Available The body protects its susceptible parts e.g. hands and feet from cold injury by allowing a surge of blood to flow through them on exposure to severe cold. This occurs through alternate vasodilatation and vasoconstriction known as Lewis Hunting Reaction. This phenomenon is influenced by several factors, which indirectly may also affect individual susceptibility to cold injury. The role of nutrition, adequate insulation of the body and positive heat balance in relation to the protective mechanism have been reviewed and discussed. Available literature on various factors has been surveyed and discussed in the light of recent advances in the physiology of cold exposure. Certain tests based on the present knowledge, to be developed and standardised for screening susceptible individuals to frost-bite have been suggested.

  14. Pain and instability during biting with mandibular implant-retained overdentures

    NARCIS (Netherlands)

    Fontijn-Tekamp, FA; Slagter, AP; van't Hof, MA; Kalk, W; Jansen, JA

    We tested in a randomized controlled clinical trial the effect of pain and instability of dentures on bite force with different degrees of mucosal support. The trial involved 3 groups who had received: 1) a new conventional denture (CD-group), 2) an implant-mucosa-borne overdenture on 2 IMZ implants

  15. Treatment of a Class II division 1 anterior open bite malocclusion.

    Science.gov (United States)

    Ong, H B

    2001-06-01

    A case report of an 11-year-old Caucasian female who presented with a Class II div I anterior open bite malocclusion. Overjet is 6 mm and the anterior open bite 2 mm. There was a history of digit sucking till she was eight years old. She was successfully treated by non-extraction with pre-adjusted Edgewise appliances and high-pull headgear for a period of 27 months.

  16. Extreme solid state refrigeration using nanostructured Bi-Te alloys.

    Energy Technology Data Exchange (ETDEWEB)

    Lima Sharma, Ana L. (San Jose State University, San Jose, CA); Spataru, Dan Catalin; Medlin, Douglas L.; Sharma, Peter Anand; Morales, Alfredo Martin

    2009-09-01

    Materials are desperately needed for cryogenic solid state refrigeration. We have investigated nanostructured Bi-Te alloys for their potential use in Ettingshausen refrigeration to liquid nitrogen temperatures. These alloys form alternating layers of Bi{sub 2} and Bi{sub 2}Te{sub 3} blocks in equilibrium. The composition Bi{sub 4}Te{sub 3} was identified as having the greatest potential for having a high Ettingshausen figure of merit. Both single crystal and polycrystalline forms of this material were synthesized. After evaluating the Ettingshausen figure of merit for a large, high quality polycrystal, we simulated the limits of practical refrigeration in this material from 200 to 77 K using a simple device model. The band structure was also computed and compared to experiments. We discuss the crystal growth, transport physics, and practical refrigeration potential of Bi-Te alloys.

  17. Bites by Australian mygalomorph spiders (Araneae, Mygalomorphae), including funnel-web spiders (Atracinae) and mouse spiders (Actinopodidae: Missulena spp).

    Science.gov (United States)

    Isbister, Geoffrey K; Gray, Mike R

    2004-02-01

    A number of mygalomorph spiders cause bites in Australia, including the funnel-web spiders (Hexathelidae, Atracinae: Hadronyche and Atrax) and mouse spiders (Actinopodidae: Missulena). There is ongoing debate about the significance of bites by mouse spiders and the frequency of severe envenoming by funnel-web spiders. We conducted a prospective cohort study of definite spider bites with expert spider identification and include the analysis of mygalomorph spiders here. Subjects were recruited prospectively from February 1999 to April 2003 from patients presenting to participating hospitals or contacting a state poison information centre. Forty-nine cases of bites by mygalomorph spiders were included: 16 were by funnel-web spiders, 13 by mouse spiders and 20 by other trapdoor spiders (Families Idiopidae and Nemesiidae). Of the 49 bites, 45 (92%) occurred on distal limbs (hands and feet). Local effects included severe pain (53%), puncture marks (61%) and bleeding (27%), local redness (33%). Itchiness did not occur. The following were highly statistically associated with mygalomorph spider bites compared to all other spiders (pweb spider bites, there were 10 cases with minor local effects, four with moderate envenoming (non-specific systemic or local neurotoxicity) and two with severe envenoming requiring antivenom. In addition to local effects, mouse spider bites caused local paraesthesia in three cases, local diaphoresis in one case and non-specific systemic effects in five cases, but not severe envenoming. True trapdoor spider bites caused only minor effects. The data from a mixed species sample of funnel-web spiders confirms previous observations suggesting that only a small proportion of funnel-web bites cause severe effects. Mouse spider bites are unlikely to cause major envenoming but the clinical effects are consistent with neurotoxic venom and are more severe than the trapdoor spiders.

  18. Nike Court Force High Lux 奢华外衣

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Nike这次将使用在Air Force1中惯用的Lux的处理手法重新包装经典的Court Force High,这两双球鞋分别采用了黑色和灰色的单色顶级绒面革物料制作鞋面。而Lux系列的标志则印制在球鞋的后跟处。这是一款设计简洁的球鞋,与时下流行的色彩潮流截然不同.也许反潮流而行之也是体现纯粹经典的好办法。

  19. Bite wounds and antibiotic prescription among patients presenting to an Australian emergency department.

    Science.gov (United States)

    Birdsey, Matthew; Edwards, Gail; Abetz, Jeremy; Jennings, Natasha; Mitra, Biswadev

    2016-07-01

    Emergency department presentations after mammalian bites may be associated with injection of bacteria into broken skin and may require prophylactic antibiotics to prevent subsequent infection. We aim to describe the epidemiology of patients presenting with a mammalian bite injury and antibiotic choice to an Australian adult tertiary centre. A retrospective cohort study was performed capturing all presentations after mammalian bite wounds between 01 Jan 2014 and 31 Dec 2014. An explicit chart review was conducted to determine management of each case. Cases were subgrouped into high- and low-risk groups as defined by the Australian Therapeutic Guidelines for animal bites. There were 160 cases of mammalian bite wounds included, with 143 (89.4%) patients grouped as high-risk and 17 (10.6%) patients identified as low-risk. High-risk features were delayed presentation > 8 hours (57 patients, 35.6%), bites to the head, hand or face (113 patients, 70.6%), and puncture wounds unable to be adequately debrided (74 patients, 46.3%). There was a significant association with delayed presentation of more than eight hours and clinically established infection [OR 36.2; 95% CI: 12.6-103.6; P antibiotics that adhered to current guidelines occurred in 99 (61.9%) cases. This study highlights variability in antibiotic prescription practice among clinicians and the need for ongoing education on antibiotic stewardship. Intervention strategies, including ongoing education, are indicated to improve adherence to antibiotic guidelines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Modified Thurow appliance: a clinical alternative for correcting skeletal open bite.

    Science.gov (United States)

    Stuani, Maria Bernadete Sasso; Stuani, Andréa Sasso; Stuani, Adriana Sasso

    2005-07-01

    Open bite malocclusion is frequently discussed in orthodontics; diagnosis, treatment, and retention can be difficult because this malocclusion has numerous correlated etiological factors. The earlier this malocclusion is corrected, the better the prognosis will be, especially when the problem is skeletal. This article presents a patient with skeletal open bite who was treated in the mixed dentition with an orthodontic appliance that included an acrylic occlusal splint and an expansion screw, based on the original Thurow appliance, to guide the vertical force against the posterior teeth and the alveolar process.

  1. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... like biting your nails, try playing with a stress ball or silly putty instead. This will help ... of hangnails, or other triggers, such as boredom, stress, or anxiety. By figuring out what causes you ...

  2. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Center Coding and reimbursement Coding MACRA Fee schedule Managing a practice Prior authorization assistance Teledermatology Compliance Choosing ... this safe, but awful-tasting formula discourages many people from biting their nails. Get regular manicures: Spending ...

  3. [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.

  4. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... a difference Career planning Media Relations Toolkit AAD apps Academy meeting Chronic urticaria—for members Chronic urticaria— ... like biting your nails, try playing with a stress ball or silly putty instead. This will help ...

  5. The 'bite' in paediatric food allergy

    African Journals Online (AJOL)

    Chantel

    Health professionals need to educate .... spread, peanut butter, polony), vegetables/mashed potato (margarine, butter, Aromat added?) History. It is not ... Cheese curls, Niknaks, cheese bites and other chips containing cheese. Smarties ...

  6. Tarantula bite leads to death and gangrene

    Directory of Open Access Journals (Sweden)

    Banerjee Kalyan

    1997-01-01

    Full Text Available Chilobrachys hardwikii-giant black hairy spider bite produced two deaths, one case of gangrene of the foot and urticarial rashes in another person in a remote village of Churulia 30 km from Asansol.

  7. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... Grant Strauss and Katz Scholarship Sulzberger Institute Grant Young Investigator Awards ... this safe, but awful-tasting formula discourages many people from biting their nails. Get regular manicures: Spending ...

  8. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... a difference Career planning Media Relations Toolkit AAD apps Academy meeting Chronic urticaria—for members Chronic urticaria— ... Injured skin Nail care Artificial nails Healthy nails Child nail care Manicure safety Nail biting Younger skin ...

  9. Spider bite-induced erythema multiforme.

    Science.gov (United States)

    Özyurt, Selçuk; Er, Onur; Afsar, Fatma Sule; Ermete, Murat

    2013-09-01

    Erythema multiforme (EM) is an immune-mediated mucocutaneous eruption characterized by symmetrically distributed, polymorphic targetoid lesions, mostly on the distal parts of the extremities. It occurs mostly in the setting of an infection in certain predisposed individuals. A 30-year-old pregnant woman was presented with a necrotic erythematous lesion on her right thigh following a spider bite. As she was pregnant for 16 weeks, no systemic medication was given. On the 8th day of the spider bite an erythematous vesicular and targetoid rash was seen on the distal parts of her extremities. Based on the clinical and histopathological findings, lesions were diagnosed as EM. She had not used any medication for 4 months and she gave no prior history of herpetic infection. So her EM lesions were thought to be an ID reaction most probably due to the spider bite. As far as we know, this is the first reported case of EM induced by a spider bite.

  10. Epidemiology of the brown recluse spider bite.

    Science.gov (United States)

    Rhoads, Jacqueline

    2007-02-01

    The purpose of this article was to provide a comprehensive epidemiological and clinical description of the brown recluse spider bite. Review of evidenced-based scientific literature and practice guidelines. A specific descriptive case study is interwoven through the article to tie in the clinical presenting figure associated with this bite. The brown recluse lives in a circumscribed area of the United States (the south central Midwest) with a few less common recluse species living in the more sparsely populated southwest United States. In these areas, where spider populations may be dense, recluse spiders may be a cause of significant morbidity. Most spider bites are asymptomatic but what makes this bite so devastating is the toxin injected by the brown recluse spider, which can cause considerable systemic symptoms as well as necrotic skin ulcers (necrotic arachnidism). The article presents process for diagnosis and stresses the importance of identifying the spider if at all possible.

  11. How to Stop Biting Your Nails

    Medline Plus

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

  12. [Acute compartment syndrome following snake bite].

    Science.gov (United States)

    Wagner, H E; Barbier, P; Frey, H P; Janggen, F M; Rothen, H U

    1986-04-01

    The experience with snake bites, causing local complications is discussed. Whenever systemic envenomation occurs, antivenin is the treatment of choice. Tissue necroses are treated by early debridement and a possible closed compartment syndrome demands the open fasciotomy.

  13. 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 ... your nails: Some doctors recommend taking a gradual approach to break the habit. Try to stop biting ...

  14. Beware of Bug Bites and Stings

    Science.gov (United States)

    ... Consumer Updates Spider Bites Ticks and Lyme Disease: Symptoms, Treatment, and Prevention Barbecue Basics: Tips to ... Consumer Updates by email. Email Address More in Consumer Updates Animal & Veterinary Children's Health Cosmetics Dietary Supplements Drugs Food Medical ...

  15. Take a Bite Out of Mosquito Stings

    Science.gov (United States)

    ... mosquito stings Share | Take a Bite Out of Mosquito Stings This article has been reviewed by Thanai ... lactic acid and carbon dioxide attract the female mosquito to skin. She inserts the tip of her ...

  16. Tick bite granuloma : recommendations for surgical treatment

    OpenAIRE

    Hirota, Keisuke; Kurosawa, Yoshinaga; Goto, Keisuke; Adachi, Koji; Yoshida, Yuichi; Yamamoto, Osamu

    2015-01-01

    Tick bite is known as a possible cause of some infectious diseases such as Lyme disease, spotted fever and related illnesses. The reaction to a tick bite may persist for several months to several years and can sometimes cause histopathological granuloma. The long-term reaction to salivary extracts from the tick could be responsible for development of granuloma in our patient. We recommended complete resection as the only sure way to treat formed granuloma.

  17. Etiological aspects of anterior open bite

    Directory of Open Access Journals (Sweden)

    Stojanović Ljiljana

    2007-01-01

    Full Text Available Introduction. Open bite is a multifactorial phenomenon and no single factor can account for open-bite. Etiology plays an important role in diagnosis. Heredity, unfavorable growth patterns, incorrect jaw postoure, are the characteristics of skeletal open bite. Digit sucking. Depending on where the thumb is placed, a number of different types of dental problems can develop. Malocclusions of the late mixed or permanent dentitions, caused by thumb sucking are not self corrected and orthodontic treatment is necessary for their correction. Lymphatic tissue. In order to produce oral respiration, the mandible is postured inferiorly with the tongue protruded and resting against the oral floor. This postural alteration induces dental and skeletal modifications similar to those caused by thumb sucking. This may cause excessive eruption of the posterior teeth, leading to an increase in the vertical dimension of the face and result in development of anterior open bite. Tongue thrust. Tongue habits cause an anterior open bite or they develop secondarily to thumb sucking. In skeletal open bite the tongue habit acts as a secondary factor which helps to maintain or exacerbate the condition. Many orthodontists have had a discouraging experience of completing dental treatment, with what appeared to be good results, only to discover that the case had relapsed because the patient had a tongue thrust swallowing pattern. Conclusion. Dentoalveolar or habitual open bite is caused by habits, which influence the growth and development of dentoalveolar processes and contribute to occlusal disharmonies. Prior to eruption of adult dentition, open bite related to oral habits is usually not a concern as when the habits stop, because the erupting dentition tends to improve spontaneously. Treatment is usually not necessary until permanent teeth erupt (~6 years old. .

  18. Venomous bites and stings in the tropical world.

    Science.gov (United States)

    Warrell, D A

    Snakes of the families Viperidae and Elapidae are responsible for the high incidence of morbidity and mortality after snake bites in countries of West Africa, the Indian subcontinent, South-East Asia, New Guinea and Latin America. Envenoming can cause local effects, notably tissue necrosis; and systemic effects, including paralysis, haemostatic disturbances, shock, increased capillary permeability, myocardial damage, rhabdomyolysis and acute renal failure. Specific hyperimmune serum (antivenom) is the mainstay of medical treatment for severe envenoming. Ancillary treatments such as assisted ventilation, repletion of circulating volume, renal dialysis and surgical debridement of necrotic tissues are needed in some cases. Scorpion stings are a common medical problem in middle and southern America, North Africa and the Middle East. Vasodilator drugs are important to counter the effects of massive catecholamine release. Bites by spiders and stings by hymenoptera and marine animals are responsible for deaths and morbidity in some tropical countries.

  19. Attonewton force detection using microspheres in a dual-beam optical trap in high vacuum

    CERN Document Server

    Ranjit, Gambhir; Stutz, Jordan H; Cunningham, Mark; Geraci, Andrew A

    2015-01-01

    We describe the implementation of laser-cooled silica microspheres as force sensors in a dual-beam optical dipole trap in high vacuum. Using this system we have demonstrated trap lifetimes exceeding several days, attonewton force detection capability, and wide tunability in trapping and cooling parameters. Measurements have been performed with charged and neutral beads to calibrate the sensitivity of the detector. This work establishes the suitability of dual beam optical dipole traps for precision force measurement in high vacuum with long averaging times, and enables future applications including the study of gravitational inverse square law violations at short range, Casimir forces, acceleration sensing, and quantum opto-mechanics.

  20. Central fatigue of the first dorsal interosseous muscle during low-force and high-force sustained submaximal contractions.

    Science.gov (United States)

    Eichelberger, Tamara D; Bilodeau, Martin

    2007-09-01

    The aim of this study was to compare the extent of central fatigue in the first dorsal interosseous (FDI) muscle of healthy adults in low, moderate and high-force submaximal contractions. Nine healthy adults completed four experimental sessions where index finger abduction force was recorded during voluntary contractions and in response to brief trains (five pulses at 100 Hz) of electrical stimulation. The ability to maximally activate FDI under volition, or voluntary activation, and its change with sustained activity (central fatigue) was assessed using the twitch interpolation technique. The fatigue tasks consisted of continuous isometric index finger abduction contractions held until exhaustion at four target force levels: 30%, 45%, 60% and 75% of the maximal voluntary contraction. The main finding was the presence of central fatigue for the 30% task, but not for the three other fatigue tasks. The extent of central fatigue was also associated with changes in a measure reflecting the status of peripheral structures/mechanisms. It appears that central fatigue contributed to task failure for the lowest force fatigue task (30%), but not for the other (higher) contraction intensities.

  1. Assessing human-dog conflicts in Todos Santos, Guatemala: bite incidences and public perception.

    Science.gov (United States)

    Lunney, Meg; Jones, Andria; Stiles, Enid; Waltner-Toews, David

    2011-12-15

    The issues surrounding dog bites are a major public health concern, particularly in areas of low income where accessibility to adequate health care, veterinary medicine and sufficient management of canine population control is low. An understanding of the risk factors associated with human-dog conflicts may be important when establishing dog bite and disease prevention strategies. In May 2008, a census of 12 consociated neighbourhoods in Todos Santos, Guatemala was conducted to investigate dog bite incidences and the public perception of free-roaming dog populations. Approximately 16.5% (78/472) of households reported at least one dog bite between May 2006 and May 2008. In total, 85 incidents occurred: 49.4% (42/85) with adults (≥18 years) and 50.6% (43/85) children (dog bites by victim gender or among age categories, there was a non-significant trend of higher cumulative incidence of dog bites in children aged six to 17 years compared to other age categories. The anatomical location of the bite varied, but bites to the legs were the most common (73/85; 85.9%). Of the 85 reported dog bites, 5.9% (5/85) were from dogs from the victims' own households, 48.2% (41/85) were from a neighbour's dog, 9.4% (8/85) were from dogs regularly seen in the community, and 15.3% (13/85) were from dogs not regularly seen in the community; the ownership status of the latter two categories of dogs could not be determined. Approximately 21% (18/85) of respondents did not know the type of dog that bit. Residents were asked for their opinions on potential problems associated with dogs in the community. The majority of respondents strongly agreed that dogs posed physical risks (78.8%; 372/472), could transmit infections to people (88.6%; 418/472), scared the family (82.4%; 389/472) and were too high in number (82.6%; 390/472). There were significant but weak correlations between owning a dog and expressing negative perceptions of community dogs (Spearman rhodog bite was not significantly

  2. The Crown Bite Jumping Herbst.

    Science.gov (United States)

    Owen, Reuel

    2003-01-01

    The Crown Bite Jumping Herbst Appliance is evaluated and combined with Straight Wire Arch Fixed Orthodontics in treatment of Class II, Division I malocclusions. This article will evaluate a combined orthodontic approach of "straightening teeth" and an orthognathic approach of "moving jaws or making skeletal changes." Orthodontic treatment cannot be accomplished well without establishing a healthy temporomandibular joint. This is defined by Keller as a joint that is "noiseless, painless and has a normal range of motion without deviation and deflection." It is not prudent to separate orthodontic treatment as its own entity without being aware of the changes in the temporomandibular joint before, during and after treatment. In other words, "If you're doing orthodontics you're doing TMJ treatment." One should treat toward a healthy, beautiful face asking, "Will proposed treatment achieve this goal?" Treatment should be able to be carried out in an efficient manner, minimizing treatment time, be comfortable and affordable for the patient, and profitable for the dentist. The finished treatment should meet Andrews' Six Keys of Occlusion, or Loudon's Twelve Commandments. Above all, do no harm to the patient. We think that a specific treatment plan can embrace these tenets. The focus will be to show Class II treatment using a modified Herbst Appliance and fixed straight wire orthodontics.

  3. 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.

  4. High-Throughput Atomic Force Microscopes Operating in Parallel

    CERN Document Server

    Sadeghian, H; Dekker, B; Winters, J; Bijnagte, T; Rijnbeek, R

    2016-01-01

    Atomic force microscopy (AFM) is an essential nanoinstrument technique for several applications such as cell biology and nanoelectronics metrology and inspection. The need for statistically significant sample sizes means that data collection can be an extremely lengthy process in AFM. The use of a single AFM instrument is known for its very low speed and not being suitable for scanning large areas, resulting in very-low-throughput measurement. We address this challenge by parallelizing AFM instruments. The parallelization is achieved by miniaturizing the AFM instrument and operating many of them simultaneously. This nanoinstrument has the advantages that each miniaturized AFM can be operated independently and that the advances in the field of AFM, both in terms of speed and imaging modalities, can be implemented more easily. Moreover, a parallel AFM instrument also allows one to measure several physical parameters simultaneously; while one instrument measures nano-scale topography, another instrument can meas...

  5. Control of biting lice, Mallophaga - a review.

    Science.gov (United States)

    Benelli, Giovanni; Caselli, Alice; Di Giuseppe, Graziano; Canale, Angelo

    2017-06-03

    The chewing lice (Mallophaga) are common parasites of different animals. Most of them infest terrestrial and marine birds, including pigeons, doves, swans, cormorants and penguins. Mallophaga have not been found on marine mammals but only on terrestrial ones, including livestock and pets. Their bites damage cattle, sheep, goats, horses and poultry, causing itch and scratch and arousing phthiriasis and dermatitis. Notably, Mallophaga can vector important parasites, such as the filarial heartworm Sarconema eurycerca. Livestock losses due to chewing lice are often underestimated, maybe because farmers notice the presence of the biting lice only when the infestation is too high. In this review, we examined current knowledge on the various strategies available for Mallophaga control. The effective management of their populations has been obtained through the employ of several synthetic insecticides. However, pesticide overuse led to serious concerns for human health and the environment. Natural enemies of Mallophaga are scarcely studied. Their biological control with predators and parasites has not been explored yet. However, the entomopathogenic fungus Metarhizium anisopliae has been reported as effective in vitro and in vivo experiments against Damalinia bovis infestation on cattle. Furthermore, different Bacillus thuringiensis preparations have been tested against Mallophaga, the most effective were B. thuringiensis var. kurstaki, kenyae and morrisoni. Lastly, plant-borne insecticides have been evaluated against Mallophaga. Tested products mainly contained bioactive principles from two Meliaceae, Azadirachta indica, and Carapa guianensis. High efficacy of neem-borne preparations was reported, leading to the development of several products currently marketed. Overall, our review highlighted that our knowledge about Mallophaga vector activity and control is extremely patchy. Their control still relied on the employ of chemical pesticides widely used to fight other

  6. An examination of the psychological aspects of bite marks.

    Science.gov (United States)

    Walter, R A

    1984-03-01

    The intent of this paper is to present some psychological threads which appear to be operative for the perpetrator of bite marks. In the catalogue of multiple motivations, there appears to be a current theme of power, control, potency, and the attempt to have a psychological symbolization of the perpetrator's omniscient capacity for absorbing life essences. In an examination of these highly complex needs, the modern perpetrator appears to act out consistently with cultural biases coupled with immediate psychological needs which have pressed for expression. Due to a pattern of psychologically expressed ritualism, the perpetrator will often inadvertently leave important psychological clues at the crime scene. The attack style, mode of death, characteristics of the victim, etc.--these components reveal the information on the type of psychological needs that the perpetrator is trying to satisfy. In the cases of bite marks associated with violent crime, it becomes crucial to an "investigator" what type of personality characteristics are welded together to form this kind of need complex. After reviewing cases reported in the literature and after conducting psychological interviews with perpetrators, three major groups of perpetrators seem to be apparent. The first group is motivated out of an anger track, the second group is motivated out of sadistic biting, and the third is out of the more traditional "cannibal complex" motif.

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

    NARCIS (Netherlands)

    Phillips, G.N.; Siekman, M.H.; Abelmann, L.; 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 ex

  8. Calculating levitation forces in the magnet-high-temperature superconductor systems

    NARCIS (Netherlands)

    Ermolaev, YS; Rudnev, IA

    2005-01-01

    A new method of calculation of the magnetic levitation force in the permanent magnet-high-temperature superconductor systems is proposed based on the Maxwell equations and the Bean model. The dependences of the levitation force on the gap width calculated for various regimes of superconductor coolin

  9. Calculating levitation forces in the magnet-high-temperature superconductor systems

    NARCIS (Netherlands)

    Ermolaev, YS; Rudnev, IA

    2005-01-01

    A new method of calculation of the magnetic levitation force in the permanent magnet-high-temperature superconductor systems is proposed based on the Maxwell equations and the Bean model. The dependences of the levitation force on the gap width calculated for various regimes of superconductor coolin

  10. High-throughput atomic force microscopes operating in parallel

    Science.gov (United States)

    Sadeghian, Hamed; Herfst, Rodolf; Dekker, Bert; Winters, Jasper; Bijnagte, Tom; Rijnbeek, Ramon

    2017-03-01

    Atomic force microscopy (AFM) is an essential nanoinstrument technique for several applications such as cell biology and nanoelectronics metrology and inspection. The need for statistically significant sample sizes means that data collection can be an extremely lengthy process in AFM. The use of a single AFM instrument is known for its very low speed and not being suitable for scanning large areas, resulting in a very-low-throughput measurement. We address this challenge by parallelizing AFM instruments. The parallelization is achieved by miniaturizing the AFM instrument and operating many of them simultaneously. This instrument has the advantages that each miniaturized AFM can be operated independently and that the advances in the field of AFM, both in terms of speed and imaging modalities, can be implemented more easily. Moreover, a parallel AFM instrument also allows one to measure several physical parameters simultaneously; while one instrument measures nano-scale topography, another instrument can measure mechanical, electrical, or thermal properties, making it a lab-on-an-instrument. In this paper, a proof of principle of such a parallel AFM instrument has been demonstrated by analyzing the topography of large samples such as semiconductor wafers. This nanoinstrument provides new research opportunities in the nanometrology of wafers and nanolithography masks by enabling real die-to-die and wafer-level measurements and in cell biology by measuring the nano-scale properties of a large number of cells.

  11. Long-term outcome in a patient with a dentoskeletal open-bite malocclusion treated without extraction.

    Science.gov (United States)

    Celli, Daniel; Gasperoni, Enrico; Deli, Roberto

    2007-01-01

    This case report describes the treatment of a patient with a Class II malocclusion with an anterior open bite. The patient, a girl 16 years of age, had a significant anteroposterior discrepancy and a high-angle tendency. Her face was convex, with competent lips. Intraorally she had an anterior open bite of 3 mm, space in the mandibular arch, and an overjet of 2 mm. High-pull headgear, anterior intermaxillary elastics, and appropriate wire bending were used to close the bite and to correct the anteroposterior dental relationship. Modification of a tongue thrust habit helped to correct this significant malocclusion and provided stability at 11 years posttreatment.

  12. Single phase forced convection cooling of high power leds

    NARCIS (Netherlands)

    Ozdemir, M.Z.; Chestakov, D.; Frijns, A.J.H.

    2011-01-01

    LEDs are strong candidates for future illumination applications dueto their much lower consumption of energy compared to conventional lighting options. One of key problems in development of LEDs is successful thermal management during illumination. Therefore, current research ongoing related to high

  13. Tick Bite by Nymphal Amblyomma testudinarium

    Science.gov (United States)

    Kim, Yeong Ho; Lee, Ji Hyun; Park, Young Min

    2016-01-01

    Ticks are parasites that usually suck the blood of wild or domestic animals; rarely, they ingest human blood and spread various febrile infectious diseases along with skin problems. Out of 40 cases of tick bite reported in Korea, only 3 were caused by nymphal ticks, and tick bites by nymphal Amblyomma testudinarium have not been reported previously. Herein, we report a rare case of tick bite by nymphal A. testudinarium. A 57-year-old woman presented with an asymptomatic solitary erythematous nodule on the left thigh that had been present for 6 days. The tick, which the patient removed from the lesion and brought to the hospital, was identified as a nymphal A. testudinarium. Doxycycline (200 mg) was used as treatment, and after seven days of use, the patient improved and no other lesions were detected. PMID:27904278

  14. Lethal case of Vipera bersus bite.

    Science.gov (United States)

    Tranca, Sebastian; Cocis, Mihaela; Antal, Oana

    2016-01-01

    Adder bites are rare events, but they can be fatal. Three adder types live in Romania - Vipera ammodytes, Vipera ursini and Vipera berus. Most adder bites happen during the summer with a peak incidence between July and August. Here we present the case of a 56 years old male patient who was bitten by an adder. The clinical presentation was severe from the beginning with a GCS of 3 points, respiratory and cardiovascular failure; despite of adequate treatment the patient developed multiorgan dysfunction and died 36 hours after the ICU admission. The aim of this report is to raise awareness that snake bites can have a life-threatening course and need immediate attention and medical care.

  15. Taking the Bite out of Bruxism (For Kids)

    Science.gov (United States)

    ... the Operating Room? Taking the Bite Out of Bruxism KidsHealth > For Kids > Taking the Bite Out of ... have bruxism (say: BRUK-siz-um). What Is Bruxism? Bruxism is the term for grinding or clenching ...

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

    Medline Plus

    Full Text Available ... plans and activities Video library Find a 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, ...

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

    Medline Plus

    Full Text Available ... MD, Memorial Award and Lectureship Grants from outside organizations Health Volunteers Overseas Grant Honorary International Society Annual ... an ice pack to the bite. If you experience any serious symptoms after a bug bite, such ...

  18. 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 ...

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

    African Journals Online (AJOL)

    2010-11-11

    Nov 11, 2010 ... Malocclusion requiring treatment was diagnosed in more than ... sucking and lip biting (20-22), nail biting (22) and ... pathologies associated with AOB include cleft lip and palate as well as trauma in condylar fractures or Le.

  20. Black widow spider bite: a case study.

    Science.gov (United States)

    Gaisford, Kristine; Kautz, Donald D

    2011-01-01

    This article is a case study of a patient cared for in the hours before her death. After the patient's death, we learned the patient died of a black widow spider bite. This article sheds light on the potential seriousness of this venom and allows for more rapid detection and treatment of those who are unfortunate enough to be bitten. The authors have documented the sequence of events for the patient, outlined the care the patient received, examined the pathophysiology of the body to a spider bite, and then made a passionate appeal for other nurses who work in critical care to do the same with patients in similar situations.

  1. [Local complications after poisonous snake bite].

    Science.gov (United States)

    Kuzbari, R; Seidler, D; Deutinger, M

    1994-01-01

    The case of a zoo keeper who was bitten on the left finger by a venomous snake (Vipera xanthina) is reported. The administration of antivenom prevented the development of systemic poisoning but had no effect on the extent of the local complications. A compartment syndrome with a concomitant severe reaction at the bite site required fasciotomy of the upper and lower arm. The extensor tendon of the involved finger ruptured spontaneously, many weeks after wound healing was completed. Therefore, delayed local complications following snake bites may occur, even if signs of systemic poisoning are missing.

  2. Bite Angle Effects in Hydroformylation Catalysis

    Institute of Scientific and Technical Information of China (English)

    van LEEUWEN

    2001-01-01

    Recent advances in rhodium catalyzed hydroformylation using xanthene-based ligands will be reviewed.The calculated natural bite angles of the ligands discussed are in the range 100-123℃ While the general trend is clear-higher 1:b ratios at wider angles, small changes in the bite angle do not exhibit a regular effect on the selectivity of the reaction.The same is true for the rate of CO dissociation;the larger the rate of the CO dissociation, the larger the rate of hydroformylation, but for small changes the effects do not comply with this rule.

  3. 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....

  4. Dispersion and optical gradient force from high-order mode coupling between two hyperbolic metamaterial waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guanghui, E-mail: gsnuwgh@163.com; Zhang, Weifeng; Lu, Jiahui; Zhao, Huijun

    2016-08-12

    We analytically study dispersion properties and optical gradient forces of different-order transverse magnetic (TM) modes in two coupled hyperbolic metamaterial waveguides (HMMWs). According to Maxwell's equations, we obtain the dispersion relation of symmetric and antisymmetric modes, and calculate optical gradient forces of different-order modes by using Maxwell stress tensor. Numerical results show that the dispersion properties are dependent on the filling ratio, and the optical gradient forces of high-order TM modes are larger than the fundamental mode when the gap between two HMMWs is very narrow, but they weaken much faster than the case of low-order TM modes with the gap width increasing. In addition, the effects of the dielectric surrounding of waveguides on the coupling effect and optical gradient force are clarified. These properties offer an avenue for various optomechanical applications in optical sensors and actuators. - Highlights: • The dependence of dispersion properties in hyperbolic metamaterials on the filling ratio is analyzed. • It is possible that the optical gradient forces of high-order modes are larger than the fundamental mode. • Optical gradient forces of high-order modes weaken much faster than the case of low-order modes. • The influence of the dielectric surrounding on the coupling effect and optical gradient force are clarified.

  5. 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.

  6. Treatment of Class II open bite in the mixed dentition with a removable functional appliance and headgear.

    Science.gov (United States)

    Ngan, P; Wilson, S; Florman, M; Wei, S H

    1992-05-01

    Early diagnosis of patients exhibiting open bites that are complicated by skeletal Class II and vertical growth problems can facilitate subsequent treatment. Eight patients with Class II skeletal open bite were treated with the high-pull activator appliance and compared to reasonably matched controls to determine the effects of the appliance. The high-pull activator was found to reduce forward growth of the maxilla and increase mandibular alveolar height, transforming the Class II molar relationship into a Class I molar relationship. The overjet and open bite were decreased, and, in addition, the appliance reduced the amount of forward and downward movement of the maxillary molars, providing vertical control of the maxilla during Class II orthopedic correction. These results demonstrated that open bite complicated by a Class II vertical growth pattern can be treated during the mixed dentition with favorable results by a combination of a removable functional appliance and high-pull headgear.

  7. Prying Force Calculation and Design Method for T-shaped Tensile Connector with High Strength Bolt

    Institute of Scientific and Technical Information of China (English)

    Zhaoxin Hou; Guohong Huang; Chao Gong

    2015-01-01

    In order to establish the design method for T⁃shaped tensile connector with high strength bolt, the theoretical analysis is carried out. Firstly, it analyzes the performance of the connector and establishes prying force calculation model. Based on the model, prying force equation and function between bolt prying force and flange thickness is derived, and the min and max thickness requirement of flange plate under a certain tension load is then obtained. Finally, two simplified design methods of the connector are proposed, which are bolt pulling capacity method and flange plate bending capacity method.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. How to Stop Biting Your Nails

    Medline Plus

    Full Text Available ... your mouth. Identify your triggers: These could be physical triggers, such as the presence of hangnails, or other triggers, such as boredom, stress, or anxiety. By figuring out what causes you to bite your nails, you can figure ...

  10. [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.

  11. Brown recluse spider bite on the breast.

    Science.gov (United States)

    Norris, Kori; Misra, Subhasis

    2014-05-01

    Brown recluse spiders are one of two types of spiders in the United States that can cause significant tissue damage and, in rare cases, death. Brown recluse spider bites are most often benign and self-limiting, but in a few cases can cause severe necrotic skin lesions.

  12. EduBites: Cliffs Notes for EPO

    Science.gov (United States)

    Brinkworth, Carolyn; Bartolone, L.; Wenger, M.; Martin, A.; Nichols-Yehling, M.; Llamas, J.; Hurt, R. L.; Squires, G. K.

    2013-06-01

    We present a new resource for the astronomy education community, with the goal of improving our community’s knowledge and understanding of the educational research papers pertinent to our work. When launched, EduBites will be a searchable database of summaries of peer-reviewed education papers, written by astronomy educators and posted for the entire community to use. While we are all aware that we should be basing our E/PO work on a solid research foundation, many people in the community are pushed for time when it comes to staying on top of the educational literature. EduBites aims to reduce that workload for the benefit of the entire community. Our database will ultimately tackle papers across the whole of the astronomy education spectrum, including formal and informal education, outreach, grades K-16, pedagogy, evaluation, and many other topics. We are keen to hear from anyone on the community who would be interested in joining our review team, and will welcome feedback on the EduBites user experience. EduBites is still currently under development but, when launched, it will be found at edubites.ipac.caltech.edu

  13. Perawatan Ortodontik pada Maloklusi Klas II Divisi 1 dengan Overjet Besar dan Palatal Bite Menggunakan Alat Cekat Teknik Begg

    Directory of Open Access Journals (Sweden)

    Reni Kurniasari

    2014-06-01

    Full Text Available Maloklusi Klas II divisi 1 sering disertai overjet besar dan palatal bite, koreksi overjet besar dan palatal bite akan sulit dilakukan dan membutuhkan waktu yang lama. Pada perawatan ortodontik menggunakan teknik Begg koreksi overjet besar dan palatal bite dapat dilakukan secara bersamaan karena memakai differential force. Tujuan artikel ini adalah untuk menyajikan hasil koreksi overjet besar dan palatal bite pada kasus maloklusi klas II divisi 1 menggunakan alat ortodontik cekat teknik Begg. Kasus: Pasien laki-laki usia 17 tahun, dengan keluhan gigi rahang atas berjejal dan maju. Diagnosis: maloklusi Angle Klas II divisi 1 dengan hubungan skeletal klas II, mandibular retrusif dan bidental protrusif disertai crowding sedang, overjet sebesar 10,78 mm, palatal bite dan pergeseran garis median rahang atas ke kiri 1,5 mm. Perawatan menggunakan alat cekat teknik Begg diawali pencabutan kedua gigi premolar pertama atas dan kedua premolar kedua rahang bawah. Tahap pertama perawatan menggunakan multiloop arch wire 0,014”, anchorage bend 45º dan elastik intermaksiler klas II. Setelah 7 bulan perawatan, hasil menunjukkan crowding terkoreksi, overjet besar dan palatal bite terkoreksi sempurna. Overjet menjadi 2,2 mm dan overbite menjadi 2 mm. Kesimpulan dari perawatan maloklusi klas II divisi 1 disertai overjet besar dan palatal bite menggunakan alat ortodontik cekat teknik Begg menunjukkan hasil yang baik. Orthodontic Treatment Of Class II Division 1 Malocclusion With Large Overjet and Palatal Bite Using Orthodontic Begg Technique. Class II division 1 often accompanied with large overjet and palatal bite, treatment of the large overjet and palatal bite would be difficult and time consuming. On orthodontic treatment using Begg technique correction of the large overjet and palatal bite can be done simultaneously for wearing a differential force. Purpose of this article is to present the results of a large overjet correction and palatal bite in case of

  14. Bite force estimates and its relationship with characteristics of diet

    OpenAIRE

    Paschetta, Carolina A.; González-José, Rolando

    2013-01-01

    La fuerza de mordida (FM) es un parámetro biomecánico que indica la cantidad de fuerza que se aplica durante la masticación de un determinado tipo de alimento. En este trabajo se compararon las FM de seis poblaciones de humanos modernos que difieren en las características de sus dietas. A partir de fotografías de la base del cráneo se digitalizaron puntos morfológicos que determinan la forma de los músculos masticadores y permiten las estimaciones de los brazos de carga y resistencia para el ...

  15. Homicide by direct snake bite: a case of contract killing.

    Science.gov (United States)

    Ambade, Vipul Namdeorao; Borkar, Jaydeo Laxman; Meshram, Satin Kalidas

    2012-01-01

    It has been estimated that five million snake bite cases occur worldwide every year, causing about 100,000 deaths. Snake bite is exclusively accidental in nature. Suicide by snake bite is very rare and homicidal snake bite is not reported. In the present case, a contract killer was hired, who used a poisonous snake to kill an elderly couple by way of direct snake bite. We believe this to be the first case reported where a snake was directly used for the murder of two victims through a contract killer.

  16. Immune-mediated mechanism for thrombocytopenia after Loxosceles spider bite.

    Science.gov (United States)

    Levin, Carina; Bonstein, Lilach; Lauterbach, Roy; Mader, Rivka; Rozemman, Dganit; Koren, Ariel

    2014-08-01

    Loxoscelism, characterized by high fever, vomiting, malaise, a dermonecrotic lesion, and thrombocytopenia, was diagnosed in a 3-year-old female. Clinical laboratory and dermatological signs are described. Blood test showed a transient hypercoagulable state and the presence of IgG antibodies against platelets, suggesting an immune-mediated mechanism for platelet destruction, in addition to the direct toxic effect of the spider venom. The finding of platelet antibodies after a Loxosceles spider bite has not been previously reported. © 2014 Wiley Periodicals, Inc.

  17. A high performance sensor for triaxial cutting force measurement in turning.

    Science.gov (United States)

    Zhao, You; Zhao, Yulong; Liang, Songbo; Zhou, Guanwu

    2015-04-03

    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.

  18. 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.

  19. 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.

  20. 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.

  1. The North–South divide in snake bite envenomation in India

    Science.gov (United States)

    Chauhan, Vivek; Thakur, Suman

    2016-01-01

    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. PMID:27904261

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

    Science.gov (United States)

    Chauhan, Vivek; Thakur, Suman

    2016-01-01

    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.

  3. 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.

  4. 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.

  5. The evolution of armament strength: evidence for a constraint on the biting performance of claws of durophagous decapods.

    Science.gov (United States)

    Taylor, G M

    2001-03-01

    Performance data for the claws of six sympatric species of Cancer crabs confirmed a puzzling pattern reported previously for two other decapod crustaceans (stone crabs, Menippe mercenaria, and lobsters, Homarus americanus): Although biting forces increased, maximum muscle stresses (force per unit area) declined with increasing claw size. The negative allometry of muscle stress and the stress at a given claw size were fairly consistent within and among Cancer species despite significant differences in adult body size and relative claw size, but were not consistent among decapod genera. Therefore, claw height can be used as a reliable predictor of maximum biting force for the genus Cancer, but must be used with caution as a predictor of maximum biting force in wider evolutionary and biogeographical comparisons of decapods. The decline in maximum muscle stress with increasing claw size in Cancer crabs contrasts with the pattern in several other claw traits. Significantly, three traits that affect maximal biting force increased intraspecifically with increasing claw size: relative claw size, mechanical advantage, and sarcomere length of the closer muscle. Closer apodeme area and angle of pinnation of the closer muscle fibers varied isometrically with claw size. The concordant behavior of these traits suggests selection for higher biting forces in larger crabs. The contrast between the size dependence of muscle stress (negative allometry) and the remaining claw traits (isometry or positive allometry) strongly suggests that an as yet unidentified constraint impairs muscle performance in larger claws. The negative allometry of muscle stress in two distantly related taxa (stone crabs and lobsters) further suggests this constraint may be widespread in decapod crustaceans. The implications of this performance constraint for the evolution of claw size and the "arms-race" between decapod predators and their hard-shelled prey is discussed.

  6. 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.

  7. Dispersion and optical gradient force from high-order mode coupling between two hyperbolic metamaterial waveguides

    Science.gov (United States)

    Wang, Guanghui; Zhang, Weifeng; Lu, Jiahui; Zhao, Huijun

    2016-08-01

    We analytically study dispersion properties and optical gradient forces of different-order transverse magnetic (TM) modes in two coupled hyperbolic metamaterial waveguides (HMMWs). According to Maxwell's equations, we obtain the dispersion relation of symmetric and antisymmetric modes, and calculate optical gradient forces of different-order modes by using Maxwell stress tensor. Numerical results show that the dispersion properties are dependent on the filling ratio, and the optical gradient forces of high-order TM modes are larger than the fundamental mode when the gap between two HMMWs is very narrow, but they weaken much faster than the case of low-order TM modes with the gap width increasing. In addition, the effects of the dielectric surrounding of waveguides on the coupling effect and optical gradient force are clarified. These properties offer an avenue for various optomechanical applications in optical sensors and actuators.

  8. Impact-force sparse reconstruction from highly incomplete and inaccurate measurements

    Science.gov (United States)

    Qiao, Baijie; Zhang, Xingwu; Gao, Jiawei; Chen, Xuefeng

    2016-08-01

    The classical l2-norm-based regularization methods applied for force reconstruction inverse problem require that the number of measurements should not be less than the number of unknown sources. Taking into account the sparse nature of impact-force in time domain, we develop a general sparse methodology based on minimizing l1-norm for solving the highly underdetermined model of impact-force reconstruction. A monotonic two-step iterative shrinkage/thresholding (MTWIST) algorithm is proposed to find the sparse solution to such an underdetermined model from highly incomplete and inaccurate measurements, which can be problematic with Tikhonov regularization. MTWIST is highly efficient for large-scale ill-posed problems since it mainly involves matrix-vector multiplies without matrix factorization. In sparsity frame, the proposed sparse regularization method can not only determine the actual impact location from many candidate sources but also simultaneously reconstruct the time history of impact-force. Simulation and experiment including single-source and two-source impact-force reconstruction are conducted on a simply supported rectangular plate and a shell structure to illustrate the effectiveness and applicability of MTWIST, respectively. Both the locations and force time histories of the single-source and two-source cases are accurately reconstructed from a single accelerometer, where the high noise level is considered in simulation and the primary noise in experiment is supposed to be colored noise. Meanwhile, the consecutive impact-forces reconstruction in a large-scale (greater than 104) sparse frame illustrates that MTWIST has advantages of computational efficiency and identification accuracy over Tikhonov regularization.

  9. Experimental study of forced convection heat transfer during upward and downward flow of helium at high pressure and high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Valentin; Narbeh Artoun; Masahiro Kawaji; Donald M. McEligot

    2015-08-01

    Fundamental high pressure/high temperature forced convection experiments have been conducted in support of the development of a Very High Temperature Reactor (VHTR) with a prismatic core. The experiments utilize a high temperature/high pressure gas flow test facility constructed for forced convection and natural circulation experiments. The test section has a single 16.8 mm ID flow channel in a 2.7 m long, 108 mm OD graphite column with four 2.3kW electric heater rods placed symmetrically around the flow channel. This experimental study presents the role of buoyancy forces in enhancing or reducing convection heat transfer for helium at high pressures up to 70 bar and high temperatures up to 873 degrees K. Wall temperatures have been compared among 10 cases covering the inlet Re numbers ranging from 500 to 3,000. Downward flows display higher and lower wall temperatures in the upstream and downstream regions, respectively, than the upward flow cases due to the influence of buoyancy forces. In the entrance region, convection heat transfer is reduced due to buoyancy leading to higher wall temperatures, while in the downstream region, buoyancyinduced mixing causes higher convection heat transfer and lower wall temperatures. However, their influences are reduced as the Reynolds number increases. This experimental study is of specific interest to VHTR design and validation of safety analysis codes.

  10. High Precision Prediction of Rolling Force Based on Fuzzy and Nerve Method for Cold Tandem Mill

    Institute of Scientific and Technical Information of China (English)

    JIA Chun-yu; SHAN Xiu-ying; NIU Zhao-ping

    2008-01-01

    The rolling force model for cold tandem mill was put forward by using the Elman dynamic recursive network method, based on the actual measured data. Furthermore, a good assumption is put forward, which brings a full universe of discourse self-adjusting factor fuzzy control, closed-loop adjusting, based on error feedback and expertise into a rolling force prediction model, to modify prediction outputs and improve prediction precision and robustness. The simulated results indicate that the method is highly effective and the prediction precision is better than that of the traditional method. Predicted relative error is less than ±4%, so the prediction is high precise for the cold tandem mill.

  11. A review of Air Force high efficiency cascaded multiple bandgap solar cell research and development

    Science.gov (United States)

    Rahilly, W. P.

    1979-01-01

    At the time of their conception, the cell stack systems to be discussed represent the best semiconductor materials combinations to achieve Air Force program goals. These systems are investigated thoroughly and the most promising systems, from the standpoint of high efficiency, are taken for further development with large area emphasized (at least 4 sq cm). The emphasis in the Air Force cascaded cell program is placed on eventual nonconcentrator application. This use of the final cell design considerably relieves the low resistance requirements for the tunnel junction. In a high concentration application the voltage drop across the tunnel junction can be a very serious problem.

  12. The black widow spider bite: differential diagnosis, clinical manifestations, and treatment options.

    Science.gov (United States)

    Shackleford, Rodney; Veillon, Diana; Maxwell, Nicole; LaChance, Lisa; Jusino, Tamara; Cotelingam, James; Carrington, Patrick

    2015-01-01

    Unrecognized and untreated black widow spider bites cause significant pain, impairment, and rarely death. The widow venom, a powerful neurotoxin known as a-latrotoxin, causes muscle pain, diaphoresis, tachycardia, flushing, and hypertension. Treatment is usually symptomatic with a combination of opioid analgesics and muscle relaxants. If symptom resolution fails, an equine IgG antiserum is available, but a high index of clinical suspicion coupled with a knowledgeable patient history often allows successful treatment, especially when the treating physician possesses awareness of this type of bite and its usual course and possible complications.

  13. Adder bite: an uncommon cause of compartment syndrome in northern hemisphere.

    Science.gov (United States)

    Evers, Lars H; Bartscher, Tanja; Lange, Thomas; Mailänder, Peter

    2010-09-20

    Snakebite envenomation is an uncommon condition in the northern hemisphere, but requires high vigilance with regard to both the systemic effects of the venom and the locoregional impact on the soft tissues. Bites from the adder, Vipera Berus, may have serious clinical consequences due to systemic effects. A case of a 44-year-old man is reported. The patient was bitten in the right hand. He developed fasciotomy-requiring compartment syndrome of the upper limb. Recognition of this most seldom complication of an adder bite is vital to save the limb. We recommend that the classical signs and symptoms of compartment syndrome serve as indication for surgical decompression.

  14. Acoustic radiation force of high-order Bessel beam standing wave tweezers on a rigid sphere.

    Science.gov (United States)

    Mitri, F G

    2009-12-01

    Particle manipulation using the acoustic radiation force of Bessel beams is an active field of research. In a previous investigation, [F.G. Mitri, Acoustic radiation force on a sphere in standing and quasi-standing zero-order Bessel beam tweezers, Annals of Physics 323 (2008) 1604-1620] an expression for the radiation force of a zero-order Bessel beam standing wave experienced by a sphere was derived. The present work extends the analysis of the radiation force to the case of a high-order Bessel beam (HOBB) of positive order m having an angular dependence on the phase phi. The derivation for the general expression of the force is based on the formulation for the total acoustic scattering field of a HOBB by a sphere [F.G. Mitri, Acoustic scattering of a high-order Bessel beam by an elastic sphere, Annals of Physics 323 (2008) 2840-2850; F.G. Mitri, Equivalence of expressions for the acoustic scattering of a progressive high order Bessel beam by an elastic sphere, IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control 56 (2009) 1100-1103] to derive the general expression for the radiation force function YJm,st(ka,beta,m)Bessel beam standing wave incident upon a rigid sphere immersed in non-viscous water are computed. The rigid sphere calculations for YJm,st(ka,beta,m)Bessel beam standing wave (m=0). The proposed theory is of particular interest essentially due to its inherent value as a canonical problem in particle manipulation using the acoustic radiation force of a HOBB standing wave on a sphere. It may also serve as the benchmark for comparison to other solutions obtained by strictly numerical or asymptotic approaches.

  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.

    2016-04-01

    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. The RSC chromatin remodelling ATPase translocates DNA with high force and small step size.

    Science.gov (United States)

    Sirinakis, George; Clapier, Cedric R; Gao, Ying; Viswanathan, Ramya; Cairns, Bradley R; Zhang, Yongli

    2011-06-15

    ATP-dependent chromatin remodelling complexes use the energy of ATP hydrolysis to reposition and reconfigure nucleosomes. Despite their diverse functions, all remodellers share highly conserved ATPase domains, many shown to translocate DNA. Understanding remodelling requires biophysical knowledge of the DNA translocation process: how the ATPase moves DNA and generates force, and how translocation and force generation are coupled on nucleosomes. Here, we characterize the real-time activity of a minimal RSC translocase 'motor' on bare DNA, using high-resolution optical tweezers and a 'tethered' translocase system. We observe on dsDNA a processivity of ∼35 bp, a speed of ∼25 bp/s, and a step size of 2.0 (±0.4, s.e.m.) bp. Surprisingly, the motor is capable of moving against high force, up to 30 pN, making it one of the most force-resistant motors known. We also provide evidence for DNA 'buckling' at initiation. These observations reveal the ATPase as a powerful DNA translocating motor capable of disrupting DNA-histone interactions by mechanical force.

  17. Multimode laser cooling and ultra-high sensitivity force sensing with nanowires

    CERN Document Server

    Hosseini, Mahdi; Slatyer, Harri J; Buchler, Ben C; Lam, Ping Koy

    2015-01-01

    Photo-induced forces can be used to manipulate and cool the mechanical motion of oscillators. When the oscillator is used as a force sensor, such as in atomic force microscopy, active feedback is an enticing route to enhancing measurement performance. Here, we show broadband multimode cooling of $-23$ dB down to a temperature of $8 \\pm 1$~K in the stationary regime. Through the use of periodic quiescence feedback cooling, we show improved signal-to-noise ratios for the measurement of transient signals. We compare the performance of real feedback to numerical post-processing of data and show that both methods produce similar improvements to the signal-to-noise ratio of force measurements. We achieved a room temperature force measurement sensitivity of $< 2\\times10^{-16}$ N with integration time of less than $0.1$ ms. The high precision and fast force microscopy results presented will potentially benefit applications in biosensing, molecular metrology, subsurface imaging and accelerometry.

  18. Radiation forces on a three-level atom in the high-order Bessel beams

    Institute of Scientific and Technical Information of China (English)

    Wang Zheng-Ling; Yin Jian-Ping

    2008-01-01

    The general expressions of the average dissipative and dipole forces acting on a A-configuration three-level atom in an arbitrary light field are derived by means of the optical Bloch equations based on the atomic density matrix elements, and the general properties of the average dissipative and dipole forces on a three-level atom in the linearly-polarized high-order Bessel beams (HBBs) are analysed. We find a resonant property (with two resonant peaks) of the dissipative force and a non-resonant property (with two pairs of non-resonant peaks) of the dipole force on the three-level atom, which are completely different from those on the two-level atom. Meanwhile we find a saturation effect of the average dissipative force in the HBB, which comes from the saturation of the upper-level population. Our study shows that the general expressions of the average dissipative and dipole forces on the three-level atom will be simplified to those of the two-level atom under the approximation of large detuning. Finally, we study the axial and azimuthal Doppler cooling of atoms in 1D optical molasses composed of two counter-propagating HBBs and discuss the azimuthal influence of the HBB on the Doppler cooling limit. We also find that the Doppler limit of atoms in the molasses HBB is slightly below the conventional Doppler limit of hг/(2кB) due to the orbital angular momentum lh of the HBB.

  19. Radiation force on absorbing targets and power measurements of a high intensity focused ultrasound (HIFU) source

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the analytic expressions for the radiated field of a circular concave piston given by Hasegawa et al.,an integral for calculation of the radiation force on a plane absorbing target in a spherically focused field is derived.A general relation between acoustic power P and normal radiation force Fn is obtained under the condition of kr 1.Numerical computation is carried out by using the symbolic computation program for practically focused sources and absorbing circular targets.The results show that,for a given source,there is a range of target positions where the radiation force is independent of the target’s position under the assumption that the contribution of the acoustic field behind the target to the radiation force can be neglected.The experiments are carried out and confirm that there is a range of target positions where the measured radiation force is basically independent of the target’s position even at high acoustic power (up to 700 W).It is believed that when the radiation force method is used to measure the acoustic power radiated from a focused source,the size of the target must be selected in such a way that no observable sound can be found in the region behind the target.

  20. Ferroelectric Domain Imaging Mechanism in High-Vacuum Scanning Force Microscopy

    Institute of Scientific and Technical Information of China (English)

    ZENG Hua-Rong; YU Han-Feng; CHU Rui-Qing; LI Guo-Rong; YIN Qing-Rui

    2005-01-01

    @@ High-vacuum scanning force microscopy of the domain structures in PMN-PT single crystals is investigated. It has been shown that under high vacuum conditions, the polarization charges are not effectively compensated for by intrinsic screening charges from the ferroelectrics. This result suggests that the electrostatic tip-sample interaction plays a great contribution to the domain imaging mechanism in PMN-PT ferroelectric single crystals under high vacuum conditions.

  1. Effect of various loads on the force-time characteristics of the hang high pull.

    Science.gov (United States)

    Suchomel, Timothy J; Beckham, George K; Wright, Glenn A

    2015-05-01

    The purpose of this study was to investigate the effect of various loads on the force-time characteristics associated with peak power during the hang high pull (HHP). Fourteen athletic men (age: 21.6 ± 1.3 years; height: 179.3 ± 5.6 cm; body mass: 81.5 ± 8.7 kg; 1 repetition maximum [1RM] hang power clean [HPC]: 104.9 ± 15.1 kg) performed sets of the HHP at 30, 45, 65, and 80% of their 1RM HPC. Peak force, peak velocity, peak power, force at peak power, and velocity at peak power were compared between loads. Statistical differences in peak force (p = 0.001), peak velocity (p < 0.001), peak power (p = 0.015), force at peak power (p < 0.001), and velocity at peak power (p < 0.001) existed, with the greatest values for each variable occurring at 80, 30, 45, 80, and 30% 1RM HPC, respectively. Effect sizes between loads indicated that larger differences in velocity at peak power existed as compared with those displayed by force at peak power. It seems that differences in velocity may contribute to a greater extent to differences in peak power production as compared with force during the HHP. Further investigation of both force and velocity at peak power during weightlifting variations is necessary to provide insight on the contributing factors of power production. Specific load ranges should be prescribed to optimally train the variables associated with power development during the HHP.

  2. 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.

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

    Science.gov (United States)

    Wise, Paul M; Wolf, Madeline; Thom, Stephen R; Bryant, Bruce

    2013-01-01

    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.

  4. Opposing Shear-Induced Forces Dominate Inertial Focusing in Curved Channels and High Reynolds Numbers

    CERN Document Server

    Keinan, Eliezer; Nahmias, Yaakov

    2015-01-01

    Inertial focusing is the migration of particles in fluid toward equilibrium, where current theory predicts that shear-induced and wall-induced lift forces are balanced. First reported in 1961, this Segre-Silberberg effect is particularly useful for microfluidic isolation of cells and particles. Interestingly, recent work demonstrated particle focusing at high Reynolds numbers that cannot be explained by current theory. In this work, we show that non-monotonous velocity profiles, such as those developed in curved channels, create peripheral velocity maxima around which opposing shear-induced forces dominate over wall effects. Similarly, entry effects amplified in high Reynolds flow produce an equivalent trapping mechanism in short, straight channels. This new focusing mechanism in the developing flow regime enables a 10-fold miniaturization of inertial focusing devices, while our model corrects long-standing misconceptions about the nature of mechanical forces governing inertial focusing in curved channels.

  5. 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.

  6. Relative Contributions of Heating and Momentum Forcing to High-Latitude Lower Thermospheric Winds

    Science.gov (United States)

    Kwak, Y. S.; Richmond, A. D.

    2015-12-01

    At high latitudes the thermospheric dynamics are gov­erned by various heat and momentum sources. Recently several modeling studies have been attempt­ed to understand the physical process that control the high-latitude lower thermospheric dynamics. Kwak and Richmond [2007] and Kwak et al. [2007] studied the momentum forcing bal­ance that are mainly responsible for maintaining the high-latitude lower thermospheric wind system by using the National Center for Atmospheric Research Thermo­sphere Ionosphere Electrodynamics General Circulation Model (NCAR TIE-GCM). Kwak and Richmond [2014] analyzed the divergence and vorticity of the high-latitude neutral wind field in the lower thermosphere during the south­ern summertime. In this study, we extend previous works by Kwak and Rich­mond [2007, 2014] and Kwak et al. [2007], which helped to better understand the physical processes maintaining thermospheric dynamics at high latitudes, and here perform a "term analysis of the potential vorticity equation" for the high-latitude neu­tral wind field in the lower thermosphere, on the basis of numerical simulations using the NCAR TIE-GCM. These analyses can provide insight into the relative strength of the heating and the momentum forcing responsible for driving rotational winds at the high-latitude lower thermosphere. The heating is the net heat including the heat transfer by downward molecular and eddy heat conduction, the absorption of solar ultraviolet (UV) and extreme ultraviolet (EUV) ra­diation, auroral heating by particles, Joule dissipation of ionospheric currents, release of chemical energy by the atomic oxygen recombination, and radiative CO2, NO and O infrared emissions. The momentum forcing is associated with the viscous force and the frictional drag force from convecting ions.

  7. 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...... and a contributory factor in the transmission of diseases. The authors examine the biology, economic importance and control of four of the most important nonbiting muscids:...

  8. Compartmental syndrome due to viper bite.

    Science.gov (United States)

    Vigasio, A; Battiston, B; De Filippo, G; Brunelli, G; Calabrese, S

    1991-01-01

    The case is reported of a young girl who was bitten on the hand by a viper and developed compartment syndrome of the intrinsic muscles more than 24 h later. Multiple dorsal and volar fasciotomies resolved the acute episode with complete restitutio ad integrum. The clinical case is discussed in detail and the literature on these rare complications of snake bites in European countries reviewed.

  9. Highly eccentric inspirals into a Schwarzschild black hole using self-force calculations

    Science.gov (United States)

    Osburn, Thomas; Warburton, Niels; Evans, Charles

    2016-03-01

    Eccentric-orbit inspirals into a massive black hole are calculated using the gravitational self-force. Both extreme-mass-ratio inspirals (EMRIs) and intermediate-mass-ratio inspirals (IMRIs) are modeled. These calculations include all dissipative and conservative first-order-in-the-mass-ratio effects for inspirals into a Schwarzschild black hole. We compute systems with initial eccentricities as high as e = 0.8 and initial separations as large as 100 M. In the case of EMRIs, the calculations follow the decay through many thousands of orbits up to the onset of the plunge. Inspirals are computed using an osculating-orbits scheme that is driven by self-force data from a hybridized self-force code. A Lorenz gauge self-force code is combined with highly accurate flux data from a Regge-Wheeler-Zerilli code, allowing the hybrid self-force model to track orbital phase in the inspirals to within 0.1 radians or better. Extensions of the method to include other physical effects are considered.

  10. Bullet Retarding Forces in Ballistic Gelatin by Analysis of High Speed Video

    CERN Document Server

    Gaylord, Steven; Courtney, Michael; Courtney, Amy

    2013-01-01

    Though three distinct wounding mechanisms (permanent cavity, temporary cavity, and ballistic pressure wave) are described in the wound ballistics literature, they all have their physical origin in the retarding force between bullet and tissue as the bullet penetrates. If the bullet path is the same, larger retarding forces produce larger wounding effects and a greater probability of rapid incapacitation. By Newton's third law, the force of the bullet on the tissue is equal in magnitude and opposite in direction to the force of the tissue on the bullet. For bullets penetrating with constant mass, the retarding force on the bullet can be determined by frame by frame analysis of high speed video of the bullet penetrating a suitable tissue simulant such as calibrated 10% ballistic gelatin. Here the technique is demonstrated with 9mm NATO bullets, 32 cm long blocks of gelatin, and a high speed video camera operating at 20,000 frames per second. It is found that different 9mm NATO bullets have a wide variety of pot...

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

    Science.gov (United States)

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

    2011-12-16

    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.

  12. 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…

  13. 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…

  14. Monsoonal response to mid-holocene orbital forcing in a high resolution GCM

    NARCIS (Netherlands)

    Bosmans, J.H.C.; Drijfhout, S.S.; Tuenter, E.; Lourens, L.J.; Hilgen, F.J.; Weber, S.L.

    2012-01-01

    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

  15. Monsoonal response to mid-holocene orbital forcing in a high resolution GCM

    NARCIS (Netherlands)

    Bosmans, J.H.C.; Drijfhout, S.S.; Tuenter, E.; Lourens, L.J.; Hilgen, F.J.; Weber, S.L.

    2012-01-01

    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 t

  16. Identification of chromosomal locations associated with tail biting and being a victim of tail-biting behaviour in the domestic pig (Sus scrofa domesticus).

    Science.gov (United States)

    Wilson, Kaitlin; Zanella, Ricardo; Ventura, Carlos; Johansen, Hanne Lind; Framstad, Tore; Janczak, Andrew; Zanella, Adroaldo J; Neibergs, Holly Louise

    2012-11-01

    The objective of this study was to identify loci associated with tail biting or being a victim of tail biting in Norwegian crossbred pigs using a genome-wide association study with PLINK case-control analysis. DNA was extracted from hair or blood samples collected from 98 trios of crossbred pigs located across Norway. Each trio came from the same pen and consisted of one pig observed to initiate tail biting, one pig which was the victim of tail biting and a control pig which was not involved in either behaviour. DNA was genotyped using the Illumina PorcineSNP60 BeadChip whole-genome single-nucleotide polymorphism (SNP) assay. After quality assurance filtering, 53,952 SNPs remained comprising 74 animals (37 pairs) for the tail biter versus control comparison and 53,419 SNPs remained comprising 80 animals (40 pairs) for the victim of tail biting versus control comparison. An association with being a tail biter was observed on Sus scrofa chromosome 16 (SSC16; p = 1.6 × 10(-5)) and an unassigned chromosome (p = 3.9 × 10(-5)). An association with being the victim of tail biting was observed on Sus scrofa chromosomes 1 (SSC1; p = 4.7 × 10(-5)), 9 (SSC9; p = 3.9 × 10(-5)), 18 (SSC18; p = 7 × 10(-5) for 9,602,511 bp, p = 3.4 × 10(-5) for 9,653,881 bp and p = 5.3 × 10(-5) for 29,577,783 bp) and an unassigned chromosome (p = 6.1 × 10(-5)). An r(2) = 0.96 and a D' = 1 between the two SNPs at 9 Mb on SSC18 indicated extremely high linkage disequilibrium, suggesting that these two markers represent a single locus. These results provide evidence of a moderate genetic association between the propensity to participate in tail-biting behaviour and the likelihood of becoming a victim of this behaviour.

  17. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Kita, Shota, E-mail: happiest3.7@gmail.com; Ueno, Toshiyuki; Yamada, Sotoshi [Kanazawa University, Kakuma-machi, Kanazawa-city, Ishikawa 920-1164 (Japan)

    2015-05-07

    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.

  19. Fresh wood reduces tail and ear biting and increases exploratory behaviour in finishing pigs.

    NARCIS (Netherlands)

    Telkanranta, H.; Bracke, M.B.M.; Valros, A.

    2014-01-01

    Chewing and rooting are high behavioural priorities in pigs. Lack of suitable materials can lead to abnormal behaviours such as tail and ear biting. In commercial farming, slatted floors limit the use of straw, and various point-source objects have therefore been developed. The crucial challenge is

  20. A survey on animal bite in children less than 16 years old in Bushehr 2001-2006

    Directory of Open Access Journals (Sweden)

    Gisoo Hatami

    2007-02-01

    Full Text Available Background: Animal bite, particularly dog bite is a prevalent public health problem which has not been taken into consideration properly. Especially, children have less experience in handling dogs and do not consider the related dangers seriously. The aim of this study was to determine incidence and related factors of animal bite in children less than 16 years old in Bushehr. Methods: In a prospective survey, all children (or their parents younger than 16 years with an animal bite were interviewed from March 2001 to March 2006 in Bushehr. Some information was collected from their medical records. Results: A total of 240 children (mean age 9.14 years, minimum 90 days and maximum 15 years old were identified. The annual incidence of animal bite was 0.19 per 1000 children between 0-15 years of age. Animal bite was higher in 10-15 years old patients and its rate was low in younger children. The most common animal bite was dog bite (79.6% and in 84.2% of cases the animal was domestic. Most of the children (65% had single lesion. The affected region in under 5 years age group and ≥5 years age group were upper limb (41.5% and lower limb (55.3% respectively (P=0.0001. The prevalence of cat bite injury was almost two times higher in girls than boys. Also cat and monkey bites were more frequent in urban than rural areas. Inpatient treatment was required in 3 cases (1.3%. All patients received Rabies immunoglobulin and completed courses of vaccination (3 or 5 times according to animal being captured or escaped. No significant associations were found between the number of wounds (single or multiple, degree of wounds (superficial or deep, sex and age (<5 or ≥5 years old with the kind of animal (domestic or wild. Conclusion: Dog bite in children is frequent. Since the cost of post exposure prophylaxis is very high for national health sector, preventive strategies should focus on public education, especially for children.

  1. Excitation Forces on Point Absorbers Exposed to High Order Non-linear Waves

    DEFF Research Database (Denmark)

    Viuff, Thomas Hansen; Andersen, Morten Thøtt; Kramer, Morten

    2013-01-01

    of proper methods to calculate design pressure distributions has led to structural failures such as buckling in the shells in wave energy prototypes. As a step towards understanding the complex loading from high order non-linear waves, this paper presents a practical approach to estimate wave excitation...... forces accounting for both non-linearity and diffraction effects. The method is validated by laboratory experiments using a hemispherical point absorber with a 6-axis force transducer, but the technique is believed to be applicable for most types of submerged or semi-submerged floating devices...

  2. Highly asymmetric interaction forces induced by acoustic waves in coupled plate structures

    CERN Document Server

    Fan, Xiying; Zhang, Shenwei; Ke, Manzhu; Liu, Zhengyou

    2015-01-01

    Mutual forces can be induced between coupled structures when illuminated by external acoustic waves. In this Letter, we propose a concept of asymmetric interaction between two coupled plate-like structures, which is generated by oppositely incident plane waves. Besides the striking contrast in magnitude, the mutual force induced by one of the incidences can be tuned extremely strong due to the resonant excitation of the flexural plate modes. The highly asymmetric interaction with enhanced strength in single side should be potentially useful, such as in designing ultrasound instruments and sensors.

  3. Prediction of forces and moments on finned bodies at high angle of attack in transonic flow

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, W. L.

    1981-04-01

    This report describes a theoretical method for the prediction of fin forces and moments on bodies at high angle of attack in subsonic and transonic flow. The body is assumed to be a circular cylinder with cruciform fins (or wings) of arbitrary planform. The body can have an arbitrary roll (or bank) angle, and each fin can have individual control deflection. The method combines a body vortex flow model and lifting surface theory to predict the normal force distribution over each fin surface. Extensive comparisons are made between theory and experiment for various planform fins. A description of the use of the computer program that implements the method is given.

  4. Kink topology control by high-frequency external forces in nonlinear Klein-Gordon models

    Science.gov (United States)

    Alvarez-Nodarse, R.; Quintero, N. R.; Mertens, F. G.

    2014-10-01

    A method of averaging is applied to study the dynamics of a kink in the damped double sine-Gordon equation driven by both external (nonparametric) and parametric periodic forces at high frequencies. This theoretical approach leads to the study of a double sine-Gordon equation with an effective potential and an effective additive force. Direct numerical simulations show how the appearance of two connected π kinks and of an individual π kink can be controlled via the frequency. An anomalous negative mobility phenomenon is also predicted by theory and confirmed by simulations of the original equation.

  5. Kink topology control by high-frequency external forces in nonlinear Klein-Gordon models.

    Science.gov (United States)

    Alvarez-Nodarse, R; Quintero, N R; Mertens, F G

    2014-10-01

    A method of averaging is applied to study the dynamics of a kink in the damped double sine-Gordon equation driven by both external (nonparametric) and parametric periodic forces at high frequencies. This theoretical approach leads to the study of a double sine-Gordon equation with an effective potential and an effective additive force. Direct numerical simulations show how the appearance of two connected π kinks and of an individual π kink can be controlled via the frequency. An anomalous negative mobility phenomenon is also predicted by theory and confirmed by simulations of the original equation.

  6. Child health update. Management of dog bites in children.

    Science.gov (United States)

    Sabhaney, Vikram; Goldman, Ran D

    2012-10-01

    A 4-year-old girl was playing with her neighbour's dog. The dog became excited and bit the girl on the forearm, leaving a puncture wound. As a result of the injury, she has presented to my office. Should she be treated with antibiotics? If so, which antibiotic should be used and for how long? Initiation of prophylactic antibiotics is indicated if the dog bite has undergone primary closure; if there is a moderate or severe bite wound; for puncture wounds (especially if penetration of bone, tendon sheath, or joint), facial bites, bites to the hands or feet, or genital area bites; or wounds sustained by victims who are immunocompromised or asplenic. The first-line choice of antibiotic is amoxicillin-clavulanate. Appropriate tetanus and rabies prophylaxis as indicated should also be a part of caring for a patient who has sustained a dog bite, as well as local debridement and thorough cleaning of the wound.

  7. 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.

  8. First Pediatric Case of Tularemia after a Coyote Bite

    Science.gov (United States)

    Chomel, Bruno B.; Morton, Jane A.; Kasten, Rickie W.; Chang, Chao-chin

    2016-01-01

    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. PMID:26885419

  9. Science Sound Bites, a Podcast for STEM Curriculum Supplementation

    Directory of Open Access Journals (Sweden)

    Michael David Leslie Johnson

    2016-05-01

    Full Text Available First hand accounts of research are a valuable part of students’ understanding and integration of scientific material, yet it is often difficult to access scientists to discuss ongoing research projects. To address this issue, we offer details of a podcast called Science Sound Bites; a tool designed to supplement STEM and biology curricula at the middle and high school grade levels. Roughly 20 minutes in length, each episode consists of a candid interview of a PhD- or MD-level researcher about their current research, while infusing and defining field-specific scientific terminology. Additionally, each Science Sound Bites podcast comes with a short biography of the interviewee and a list of terms that are defined within the episode, which serves to help teachers find relevant podcasts for a given lesson plan. The goal of this podcast is to provide real world applications of science in an attempt to bridge the gap between scientists in the field and students in the classroom.

  10. Experimental Contribution to High-Precision Characterization of Magnetic Forces in Active Magnetic Bearings

    DEFF Research Database (Denmark)

    Kjølhede, Klaus; Santos, Ilmar

    2007-01-01

    Parameter identification procedures and model validation are major steps toward intelligent machines supported by active magnetic bearings (AMB). The ability of measuring the electromagnetic bearing forces, or deriving them from measuring the magnetic flux, strongly contributes to the model...... 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...... gap variations, monitoring the bearing input signals. Advantages and drawbacks of the different methodologies are critically discussed. The linearity ranges are experimentally determined and the characterization of magnetic forces with a high accuracy of

  11. Experimental Contribution to High Precision Characterization of Magnetic Forces in Active Magnetic Bearings

    DEFF Research Database (Denmark)

    Kjølhede, Klaus; Santos, Ilmar

    2006-01-01

    Parameter identification procedures and model validation are major steps towards intelligent machines supported by active magnetic bearings (AMB). The ability of measuring the electromagnetic bearing forces, or deriving them from measuring the magnetic flux, strongly contributes to the model...... of the magnetic forces is conducted using different experimental tests: (a) 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, (b) by measuring the input current and bearing...... gap variations, monitoring the bearing input signals. Advantages and drawbacks of the different methodologies are critically discussed. The linearity ranges are experimentally determined and the characterization of magnetic forces with a high accuracy of less than 1% is achieved. (%error is normalized...

  12. Force measurement and design of a torquing high-pull headgear.

    Science.gov (United States)

    Tabash, J W; Sandrik, J L; Bowman, D; Lang, R L; Klapper, L

    1984-07-01

    The dynamic extraoral force analyzer (DEFA) was found to be capable of measuring linear deflection as a function of force created by a headgear. Ten standard nontorqued face-bows with a cervical and a high-pull direction were tested to determine the reliability of the DEFA. Statistical analysis showed the DEFA to be reliable and accurate in differentiating various directions and deflections of maxillary molars. Doubled-over distal ends of the inner bow with 0 degree of torque and a parietal direction of pull were used as controls. The same face-bows with 9 degrees of buccal root torque were tested on the DEFA. These face-bows were tested to determine whether transverse translation without buccal crown tipping of the maxillary first molar will occur. Statistical analysis showed that transverse translation occurred at a force of 200 to 347 gm.

  13. VARYING A V BLOCK COMPLICATING SNAKE BITE - A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Vikas

    2014-02-01

    Full Text Available Snake venom toxicities comprise mainly bleeding disorders and nephrotoxicity. Cardiotoxicity is a rare manifestation of snake bite. We describe the case of a previously healthy 23 - year - old man who developed coagulopathy and AV node dysfunction following snake bite. Electrocardiography showed all variatio ns of AV conduction dysfunction . This is the first account of AV node dysfu nction caused by a snake bite with cardiotoxi city presenting as atrioventricular block

  14. Case report: acute demyelinating encephalomyelitis following viper bite

    OpenAIRE

    Xu, Anyi; Shan, Renfei; Huang, Daochao; Zhou, Jiajia; Keenoo, Anaswasseem; Qin, Jie

    2016-01-01

    Abstract The most serious complications of the central nervous system that occur after venomous snake bite are intracranial hemorrhage and ischemic stroke. We present a rarely seen central nervous system complication, acute demyelinating encephalomyelitis, after a treated Deinagkistrodon's viper bite. On April 5, 2015, a 50-year-old male farmer was bitten on his right leg by a Deinagkistrodon's viper. The bite rendered the victim unconscious for 14 days, during which he was treated with tetan...

  15. Utilization of a modified bite guard for preventing traumatic macroglossia.

    Science.gov (United States)

    Karayazgan-Saracoglu, Banu; Kecik, Defne

    2011-01-01

    This clinical report describes the treatment of a patient having traumatic macroglossia due to schwannoma in the craniocervical region. Enlarged tongue or macroglossia may compromise vital functions of the patient. To avoid a chronic tongue bite trauma, a bite guard that was inspired from a habit breaker was fabricated. Tongue injury has significantly healed with the use of this appliance, and the patient was able to masticate without biting on his tongue.

  16. A new class of high force, low-voltage, compliant actuation system

    Energy Technology Data Exchange (ETDEWEB)

    RODGERS,M. STEVEN; KOTA,SRIDHAR; HETRICK,JOEL; LI,ZHE; JENSEN,BRIAN D.; KRYGOWSKI,THOMAS W.; MILLER,SAMUEL L.; BARNES,STEPHEN MATTHEW; BURG,MICHAEL STANLEY

    2000-04-10

    Although many actuators employing electrostatic comb drives have been demonstrated in a laboratory environment, widespread acceptance in mass produced microelectromechanical systems (MEMS) may be limited due to issues associated with low drive force, large real estate demands, high operating voltages, and reliability concerns due to stiction. On the other hand, comb drives require very low drive currents, offer predictable response, and are highly compatible with the fabrication technology. The expand the application space and facilitate the widespread deployment of self-actuated MEMS, a new class of advanced actuation systems has been developed that maintains the highly desirable aspects of existing components, while significantly diminishing the issues that could impede large scale acceptance. In this paper, the authors will present low-voltage electrostatic actuators that offer a dramatic increase in force over conventional comb drive designs. In addition, these actuators consume only a small fraction of the chip area previously used, yielding significant gains in power density. To increase the stroke length of these novel electrostatic actuators, the authors have developed highly efficient compliant stroke amplifiers. The coupling of compact, high-force actuators with fully compliant displacement multipliers sets a new paradigm for highly integrated microelectromechanical systems.

  17. Temporomandibular joint forces measured at the condyle of Macaca arctoides.

    Science.gov (United States)

    Boyd, R L; Gibbs, C H; Mahan, P E; Richmond, A F; Laskin, J L

    1990-06-01

    Forces were measured at the articular surface of the temporomandibular joint (TMJ) condyle in two stump-tail monkeys (Macaca arctoides) during chewing, incisal biting, and drinking and also during aggressive behaviors. Force was measured with a thin piezoelectric foil transducer, which was cemented over the anterior and superior surfaces of the condyle. Wires from the upper and lower surfaces of the foil were insulated between two layers of Teflon tape and run subcutaneously to a telemetry unit, which was implanted in the upper back. Force applied across the foil by the condyle was detected by the telemetry unit and transmitted to an FM radio receiver outside the animal. The FM signals were received and demodulated, and a signal proportional to the force applied between the condyle and the TMJ fossa was displayed on a chart recorder. Data were collected over an 8-day period. The animals were not constrained. The TMJ was found to be load bearing. The greatest force of 39.0 lb (17.7 kg) was measured during feisty vocal aggression. Forces ranged as high as 34.5 lb (15.7 kg) during chewing and 28.5 lb (13.0 kg) during incisal biting. Forces were greater on the working (food) side than on the nonworking (balancing) side by average ratios of 1.4 to 2.6. A large unilateral interference at the most distal molar greatly disturbed chewing. It reduced TMJ forces by 50% or more, and the monkey refused to chew on the side opposite the interference.

  18. Bilateral parotid enlargement following snake bite:A rare sign

    Institute of Scientific and Technical Information of China (English)

    Madi Deepak; Achappa Basavaprabhu; John T Ramapuram; Chowta Nithyananda; Soundarya Mahalingam

    2013-01-01

    Snakebite is a common medical emergency in India. Unusual complications may occur after viper bite. Bilateral parotid enlargement after viper bite is a rare entity. An 18-year old gentleman presented to our hospital with history of viper bite. On examination he had cellulitis of right lower limb. He developed swelling of both the parotid glands 12 h after admission. He developed coagulopathy, acute renal failure and died within 48 h of hospital admission. Development of parotid swelling after snake bite is associated with poor prognosis. This case is found worth reporting as it is an unusual complication having prognostic value.

  19. Animal and Human Bites: Prophlaxis and Approach to the Treatment

    Directory of Open Access Journals (Sweden)

    Ahmet KARAKAŞ

    2010-09-01

    Full Text Available Human and animal bites can cause complications ranging from slight injuries to serious infections. Infections can originate from the biter’s oral cavity and victims’s skin flora. Compared with animal bites, human bites have a higher risk of infection development. Most of the wound infections due to bites are caused by polymicrobials. Pasteurella species, streptococci, staphylococci, Moraxella, Corynebacterium, and Neisseria spp., Bergeyella zoohelcum and Capnocytophaga species are the most frequently isolated pathogens. Dogs (85-90 %, cats (5-10 %, humans (2-3 % and rodents (2-3 % are responsible for most of the bite injuries. Injuries due to dog bites occur mostly in men older than 20 years old and usually on the extremities. Cat bites and related injuries are found in 66 % on the upper extremities, typically on the hands. Bites of human origin are mostly occur in males between the ages of 20-30, and especially seen on the arms, fingers and head-neck regions. Most of the bites from rodents have a rat origin. Those bites often happen at night , especially on the face or hand of children under five years old who live in poor hygienic conditions. The dog bites are mostly due to the crush-style injuries and in 4-25 % of those injuries an infection develops in about 24 hours. Because of their sharp teeth, cats cause puncture-type wounds. Approximately 30-50 % of the cat bite wounds become infected 12 hours later. Hand, face and genital region wounds have a higher risk for the occurrence of an infection, because of their special anatomical structure. In case of risk factors such as diabetes mellitus, kidney failure, long term steroid use, splenectomy, extreme ages (children and elderly people and systemic lupus erythematosus (SLE, infection could easily spread to the deep tissues. The suturing of bite wounds remain controversial. Infected wounds and bites older than 24 hours could be left open. Cosmetically problematic wounds like on the face

  20. 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 ...

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

    Science.gov (United States)

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

    2011-10-01

    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.

  2. LIFT FORCE ON ROTATING SPHERE AT LOW REYNOLDS NUMBERS AND HIGH ROTATIONAL SPEEDS

    Institute of Scientific and Technical Information of China (English)

    由长福; 祁海鹰; 徐旭常

    2003-01-01

    The lift force on an isolated rotating sphere in a uniform flow was investigated by means of a three-dimensional numerical simulation for low Reynolds numbers (based on the sphere diameter) (Re < 68.4) and high dimensionless rotational speeds (Γ< 5). The Navier-Stokes equations in Cartesian coordinate system were solved using a finite volume formulation based on SIMPLE procedure. The accuracy of the numerical simulation was tested through a comparison with available theoretical, numerical and experimental results at low Reynolds numbers, and it was found that they were in close agreement under the above mentioned ranges of the Reynolds number and rotational speed. From a detailed computation of the flow field around a rotational sphere in extended ranges of the Reynolds number and rotational speed, the results show that, with increasing the rotational speed or decreasing the Reynolds number, the lift coefficient increases. An empirical equation more accurate than those obtained by previous studies was obtained to describe both effects of the rotational speed and Reynolds number on the lift force on a sphere. It was found in calculations that the drag coefficient is not significantly affected by the rotation of the sphere. The ratio of the lift force to the drag force, both of which act on a sphere in a uniform flow at the same time, was investigated. For a small spherical particle such as one of about 100μm in diameter, even if the rotational speed reaches about 106 revolutions per minute, the lift force can be neglected as compared with the drag force.

  3. 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.

  4. Geographic access to street food sources for dogs and its association with spatial patterns of animal bite injuries in Enugu, Nigeria, 2005-2011.

    Science.gov (United States)

    Olugasa, B O; Okeke, O S; Ishola, O O

    2014-12-01

    Accessibility of street food source to dogs in Enugu, the capital city of Enugu State, south-eastern Nigeria was examined in relation to spatial patterns of animal bite injuries in the city. Retrospective data on animal bite injuries were retrieved from records of selected hospitals in Enugu and its environs during the period 2005-2011. Victim's residence and street point where animal bite incidence occurred were geo-referenced. Street food sources, including garbage disposal points, meat markets, slaughter facilities and public vehicle terminals in the city were observed and geo-referenced. Thematic maps were designed usingArcGIS 10.1. Spatial scan statistics was used to identify cluster pattern of animal bite injuries and fatal rabies cases. Coefficient of area correspondence (Ca) in spatial cluster with selected variables was computed. One hundred and thirty one cases of animal bite injury cases were retrieved with traceable addresses. These comprised cat bites (n = 1, 0.76%), goat bites (n = 1, 0.76%), monkey bites (n = 2, 1.5%) and dog bites (n = 127, 96.98%). Fatal outcomes (n = 4, 3.15%) were recorded. Males within the age group, 0-15 (46.5%) were at the highest risk. A diffused spatial pattern showed that majority of the study area experienced animal bite injury during the study period. A primary cluster of 15.03km radius and a secondary cluster of 1.11 km radius traversed residential and non-residential areas were identified as rabies high- and low-risk areas. Interspecies bites from non-carnivores (goats and monkeys) and resultant deaths with neurologic signs were pathognomonic for rabies-like-illness in Enugu State. High Ca (0.8) showed a strong correlation between access to street food sources for dogs and the distribution of animal bite injuries on humans. While access to street food may support the population of free-roaming dogs, it was also shown to be partly explanatory to spatial patterns of dog bite injury. Public education about responsible pet

  5. A fast high-order method to calculate wakefield forces in an electron beam

    CERN Document Server

    Qiang, Ji; Ryne, Robert D

    2012-01-01

    In this paper we report on a high-order fast method to numerically calculate wakefield forces in an electron beam given a wake function model. This method is based on a Newton-Cotes quadrature rule for integral approximation and an FFT method for discrete summation that results in an $O(Nlog(N))$ computational cost, where $N$ is the number of grid points. Using the Simpson quadrature rule with an accuracy of $O(h^4)$, where $h$ is the grid size, we present numerical calculation of the wakefields from a resonator wake function model and from a one-dimensional coherent synchrotron radiation (CSR) wake model. Besides the fast speed and high numerical accuracy, the calculation using the direct line density instead of the first derivative of the line density avoids numerical filtering of the electron density function for computing the CSR wakefield force.

  6. Onychophagia (Nail biting), anxiety, and malocclusion.

    Science.gov (United States)

    Sachan, Avesh; Chaturvedi, T P

    2012-01-01

    Nail biting is a stress removing habit adopted by many children and adults. People usually do it when they are nervous, stressed, hungry, or bored. All of these situations are having a common phenomenon between them is anxiety. Onychophagia is also a sign of other emotional or mental disorders. It is a habit that is not easy to quit and reflection of extreme nervousness or inability to handle stressful conditions. This abnormal habit may cause various malocclusions associated with dentoalveolar segment of the oral cavity. Crowding and rotations of incisors are common with this habit.

  7. Onychophagia (Nail biting, anxiety, and malocclusion

    Directory of Open Access Journals (Sweden)

    Avesh Sachan

    2012-01-01

    Full Text Available Nail biting is a stress removing habit adopted by many children and adults. People usually do it when they are nervous, stressed, hungry, or bored. All of these situations are having a common phenomenon between them is anxiety. Onychophagia is also a sign of other emotional or mental disorders. It is a habit that is not easy to quit and reflection of extreme nervousness or inability to handle stressful conditions. This abnormal habit may cause various malocclusions associated with dentoalveolar segment of the oral cavity. Crowding and rotations of incisors are common with this habit.

  8. Measuring the interaction force between a high temperature superconductor and a permanent magnet

    OpenAIRE

    Valenzuela, S. O.; Jorge, G. A.; Rodriguez, E.

    1999-01-01

    Repulsive and attractive forces are both possible between a superconducting sample and a permanent magnet, and they can give place to magnetic levitation or free-suspension phenomena, respectively. We show experiments to quantify this magnetic interaction which represents a promising field regarding to short-term technological applications of high temperature superconductors. The measuring technique employs an electronic balance and a rare-earth magnet that induces a magnetic moment in a melt...

  9. 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.

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

    Science.gov (United States)

    Sheng, Xiaozhen; Liu, Yuxia; Zhou, Xin

    2016-09-01

    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.

  11. [Prevalence of anterior open bite and overjet preschoolers in the city of Recife (PE, Brazil)].

    Science.gov (United States)

    Granville-Garcia, Ana Flávia; Ferreira, Jainara Maria Soares; Menezes, Valdenice Aparecida de

    2010-10-01

    The objective of this work was to verify the prevalence of malocclusions (anterior open bite, overjet) and its association with age, gender and type of school with a sample of 2,651 preschool children in the city of Recife, PE, Brazil. The children were seated in school chairs in the room of the day care/school for the clinical exam, children aging two years or less were assisted in the system knee-knee, through natural and artificial illumination. The dental protrusion was verified when the overjet was larger than 3 mm through periodontal probe in millimeters. The presence of anterior open bite was detected when there was no contact with the anterior teeth and the posterior ones stayed in occlusion. t was also registered in clinical record a combination of the two malocclusions types, in other words, open bite and of dental protrusion. The data were analyzed at Qui-square and the association among the events was the odds ratio. The prevalence of protrusion was 66.1% and previous open bite 19.8%. There was association among this malocclusions, age and type of school, however there was not significant statistical association between malocclusion and gender. It was concluded that the prevalence of malocclusion in preschoolers was high and it was associated to the age and school type.

  12. 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

    ). Of the respondents, 5.2% reported a history of dog bite in at least one family member, and 11.8% reported a history of dog bite in domestic animals during the previous year. The HHs having a higher number of family members (OR: 1.13, 95% CI: 1.07–1.2), having a pet dog (OR: 2.1, 95% CI: 1.4–3.2) and caring......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...

  13. Dog-bite induced sepsis : a report of four cases

    NARCIS (Netherlands)

    Hovenga, S; Tulleken, JE; Moller, LVM; Jackson, SA; Van der Werf, TS; Zijlstra, JG

    1997-01-01

    Occasionally, a dog-bite is complicated by a systemic overwhelming infection. We report four consecutive patients who were admitted to our intensive care unit because of sepsis syndrome following dog-bites. The history of these patients did not reveal any immunocompromising conditions. Capnocytophag

  14. 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 ...

  15. Primate bites in Gibraltar--minor casualty quirk?

    Science.gov (United States)

    Campbell, A C

    1989-10-01

    In one year 55 patients presented to the casualty department of St Bernard's Hospital, Gibraltar, with a primate bite. The implications of such wounds on the health of these patients is contrasted with the morbidity and mortality associated with primate bites in the African subcontinent.

  16. 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...

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

    Medline Plus

    Full Text Available ... counter oral antihistamine. To reduce swelling , apply an ice pack to the bite. If you experience any serious symptoms after a bug bite, such as a rash, fever, or body aches, see your doctor or a board-certified dermatologist immediately. Make sure you tell the doctor about your recent ...

  18. 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 ...

  19. Bite angle effects of diphosphines in carbonylation reactions

    NARCIS (Netherlands)

    P.W.N.M. van Leeuwen; Z. Freixa

    2008-01-01

    This chapter contains sections titled: * Introduction * Rhodium-Catalyzed Hydroformylation o Introduction o Steric Bite Angle Effect and Regioselectivity o Electronic Bite Angle Effect and Activity o Isotope Effects [24] * Platinum-Catalyzed Alkene Hydroformylation * Palladium-Catalyzed CO/Ethene Co

  20. Validity and reliability of the T-Scan(®) III for measuring force under laboratory conditions.

    Science.gov (United States)

    Cerna, M; Ferreira, R; Zaror, C; Navarro, P; Sandoval, P

    2015-07-01

    Although measuring bite force is an important indicator of the health of the masticatory system, few commercially available transducers have been validated for routine clinical use. T-Scan(®) III Occlusal Analysis System allows to record the bite force distribution, indicating its relative intensity and occlusal timing. Nevertheless, even fewer studies have evaluated the validity and reliability of the latest generation of the T-Scan(®) occlusal analysis system. To determine the validity and reliability of the T-Scan(®) III system when measuring total absolute bite force under laboratory conditions. Known forces were applied to 18 T-Scan(®) III sensors, which were classified into two groups differentiated by their production series. Both Lin's concordance correlation coefficient (CCC) and the intra-class correlation coefficient (ICC) were used to assess the system's reliability and validity. Considering all the sensors studied, a substantial level (Lin's CCC 0·969) and a very good level of reliability (CCI 0·994) were obtained. When evaluating the validity of the system, a poor (Lin's CCC 0·530) and moderate (ICC 0·693) agreement were also obtained. The main factor that negatively influenced the validity of the T-Scan(®) III under these study conditions was the significant difference in the behaviour of the two sensor groups. The T-Scan(®) III showed a high degree of reliability when used to perform consecutive measurements. However, the system showed an insufficient degree of validity for measuring absolute force when estimating total occlusal force under laboratory conditions. © 2015 John Wiley & Sons Ltd.

  1. Casimir force between $\\delta-\\delta^{\\prime}$ mirrors transparent at high frequencies

    CERN Document Server

    Braga, Alessandra N; Alves, Danilo T

    2016-01-01

    We investigate, in the context of a real massless scalar field in $1+1$ dimensions, models of partially reflecting mirrors simulated by Dirac $\\delta-\\delta^{\\prime}$ point interactions. In the literature, these models do not exhibit full transparency at high frequencies. In order to provide a more realistic feature for these models, we propose a modified $\\delta-\\delta^{\\prime}$ point interaction that enables to achieve full transparency in the limit of high frequencies. Taking this modified $\\delta-\\delta^{\\prime}$ model into account, we investigate the Casimir force, comparing our results with those found in the literature.

  2. High resolution miniature dilatometer based on an atomic force microscope piezocantilever

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.-H.; Graf, D.; Murphy, T. P.; Tozer, S. W. [National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310 (United States); Schmiedeshoff, G. M. [Department of Physics, Occidental College, Los Angeles, California 90041 (United States)

    2009-11-15

    Thermal expansion, or dilation, is closely related to the specific heat, and provides useful information regarding material properties. The accurate measurement of dilation in confined spaces coupled with other limiting experimental environments such as low temperatures and rapidly changing high magnetic fields requires a new sensitive millimeter size dilatometer that has little or no temperature and field dependence. We have designed an ultracompact dilatometer using an atomic force microscope piezoresistive cantilever as the sensing element and demonstrated its versatility by studying the charge density waves in alpha uranium to high magnetic fields (up to 31 T). The performance of this piezoresistive dilatometer was comparable to that of a titanium capacitive dilatometer.

  3. Radiation forces on a Rayleigh dielectric sphere produced by highly focused parabolic scaling Bessel beams.

    Science.gov (United States)

    Guo, Mengwen; Zhao, Daomu

    2017-02-20

    The radiation forces on a Rayleigh dielectric particle induced by a highly focused parabolic scaling Bessel beam (PSBB) are investigated. Numerical results show that the zero-order PSBB can be used to trap a high-index particle at the focus and near the focus by the first-order PSBB. For the low-index particle, it can be guided or confined in the dark core of the nonzero-order PSBB but cannot be stably trapped in this single-beam trap. Further, we analyze the condition of trapping stability. It is found that the lower limit in the particle radius for stable trapping is different for different orders.

  4. High-speed atomic force microscope based on an astigmatic detection system

    Energy Technology Data Exchange (ETDEWEB)

    Liao, H.-S.; Chen, Y.-H.; Hwu, E.-T.; Chang, C.-S.; Hwang, I.-S., E-mail: ishwang@phys.sinica.edu.tw [Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China); Ding, R.-F.; Huang, H.-F.; Wang, W.-M. [Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China); Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Huang, K.-Y. [Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

    2014-10-15

    High-speed atomic force microscopy (HS-AFM) enables visualizing dynamic behaviors of biological molecules under physiological conditions at a temporal resolution of 1s or shorter. A small cantilever with a high resonance frequency is crucial in increasing the scan speed. However, detecting mechanical resonances of small cantilevers is technically challenging. In this study, we constructed an atomic force microscope using a digital versatile disc (DVD) pickup head to detect cantilever deflections. In addition, a flexure-guided scanner and a sinusoidal scan method were implemented. In this work, we imaged a grating sample in air by using a regular cantilever and a small cantilever with a resonance frequency of 5.5 MHz. Poor tracking was seen at the scan rate of 50 line/s when a cantilever for regular AFM imaging was used. Using a small cantilever at the scan rate of 100 line/s revealed no significant degradation in the topographic images. The results indicate that a smaller cantilever can achieve a higher scan rate and superior force sensitivity. This work shows the potential for using a DVD pickup head in future HS-AFM technology.

  5. 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.

  6. 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

    2017-02-01

    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.

  7. Experimental and numerical investigation of nanoparticle releasing in AFM nanomanipulation using high voltage electrostatic forces

    Science.gov (United States)

    Ghattan Kashani, H.; Shokrolahi, S.; Akbari Moayyer, H.; Shariat Panahi, M.; Shahmoradi Zavareh, A.

    2017-07-01

    Atomic Force Microscopes (AFMs) have been widely used as nanomanipulators due to their versatility to work with a broad range of materials and their controllable interaction force, among other features. While AFMs can effectively grasp, move, and position nanoscale objects in 2D environments through basic pull/push operations, they often lack the high precision required in many 3D pick and place applications, especially in non-vacuum environments. In this study, a novel method to resolve the adhesion problem between nanoscale objects and the AFM tip has been developed and tested. The method is based on the application of a high electrostatic voltage to the tip to produce the repulsive force required for the release of the nanoobject. The method is proposed for conductive nanoparticles and tips used in many nanomanipulation applications, and can be easily implemented on typical AFMs with minimal alterations. The applicability of the proposed method is investigated through a series of combined Molecular Dynamics/Finite Element simulations.

  8. High-resolution dynamic atomic force microscopy in liquids with different feedback architectures

    Directory of Open Access Journals (Sweden)

    John Melcher

    2013-02-01

    Full Text Available The recent achievement of atomic resolution with dynamic atomic force microscopy (dAFM [Fukuma et al., Appl. Phys. Lett. 2005, 87, 034101], where quality factors of the oscillating probe are inherently low, challenges some accepted beliefs concerning sensitivity and resolution in dAFM imaging modes. Through analysis and experiment we study the performance metrics for high-resolution imaging with dAFM in liquid media with amplitude modulation (AM, frequency modulation (FM and drive-amplitude modulation (DAM imaging modes. We find that while the quality factors of dAFM probes may deviate by several orders of magnitude between vacuum and liquid media, their sensitivity to tip–sample forces can be remarkable similar. Furthermore, the reduction in noncontact forces and quality factors in liquids diminishes the role of feedback control in achieving high-resolution images. The theoretical findings are supported by atomic-resolution images of mica in water acquired with AM, FM and DAM under similar operating conditions.

  9. Forced and natural gradient tracer tests in a highly heterogeneous porous aquifer: instrumentation and measurements

    Science.gov (United States)

    Ptak, T.; Teutsch, G.

    1994-07-01

    At the Horkheimer Insel experimental field site, several short to intermediate distance forced and natural gradient tracer tests with depth-integrated and multilevel sampling were conducted to characterize the aquifer transport properties. Compared with other test sites, the aquifer at the Horkheimer Insel is highly heterogeneous and highly conductive. Hence, new tracer measurement techniques had to be developed. This paper presents some of the instrumentation developed together with measurements and their initial interpretation. The results demonstrate that for contaminant transport predictions in highly heterogeneous and highly conductive aquifers, investigation techniques with a high resolution in time and space are needed. The aquifer heterogeneity is evident from the spatial variability of peak concentration, transport velocity and longitudinal macrodispersivity values obtained from the tracer tests. Furthermore, the tracer test results indicate that at the observation scale investigated, a complex numerical flow and transport model is needed to describe adequately mass transport within the heterogeneous aquifer.

  10. High sensitivity piezomagnetic force microscopy for quantitative probing of magnetic materials at the nanoscale.

    Science.gov (United States)

    Chen, Qian Nataly; Ma, Feiyue; Xie, Shuhong; Liu, Yuanming; Proksch, Roger; Li, Jiangyu

    2013-07-01

    Accurate scanning probing of magnetic materials at the nanoscale is essential for developing and characterizing magnetic nanostructures, yet quantitative analysis is difficult using the state of the art magnetic force microscopy, and has limited spatial resolution and sensitivity. In this communication, we develop a novel piezomagnetic force microscopy (PmFM) technique, with the imaging principle based on the detection of magnetostrictive response excited by an external magnetic field. In combination with the dual AC resonance tracking (DART) technique, the contact stiffness and energy dissipation of the samples can be simultaneously mapped along with the PmFM phase and amplitude, enabling quantitative probing of magnetic materials and structures at the nanoscale with high sensitivity and spatial resolution. PmFM has been applied to probe magnetic soft discs and cobalt ferrite thin films, demonstrating it as a powerful tool for a wide range of magnetic materials.

  11. Schlieren High Speed Imaging on Fluid Flow in Liquid Induced by Plasma-driven Interfacial Forces

    Science.gov (United States)

    Lai, Janis; Foster, John

    2016-10-01

    Effective plasma-based water purification depends heavily on the transport of plasma-derived reactive species from the plasma into the liquid. Plasma interactions at the liquid-gas boundary are known to drive circulation in the bulk liquid. This forced circulation is not well understood. A 2-D plasma- in-liquid water apparatus is currently being investigated as a means to study the plasma-liquid interface to understand not only reactive species flows but to also understand plasma- driven fluid dynamic effects in the bulk fluid. Using Schlieren high speed imaging, plasma-induced density gradients near the interfacial region and into the bulk solution are measured to investigate the nature of these interfacial forces. Plasma-induced flow was also measured using particle imaging velocimetry. NSF CBET 1336375 and DOE DE-SC0001939.

  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. 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.

  14. Measuring the interaction force between a high temperature superconductor and a permanent magnet

    Science.gov (United States)

    Valenzuela, S. O.; Jorge, G. A.; Rodríguez, E.

    1999-11-01

    Repulsive and attractive forces are both possible between a superconducting sample and a permanent magnet, and they can give rise to magnetic levitation or free-suspension phenomena, respectively. We show experiments to quantify this magnetic interaction, which represents a promising field with regard to short-term technological applications of high temperature superconductors. The measuring technique employs an electronic balance and a rare-earth magnet that induces a magnetic moment in a melt-textured YBa2Cu3O7 superconductor immersed in liquid nitrogen. The simple design of the experiments allows a fast and easy implementation in the advanced physics laboratory with a minimum cost. Actual levitation and suspension demonstrations can be done simultaneously as a help to interpret magnetic force measurements.

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

    Energy Technology Data Exchange (ETDEWEB)

    Iwata, F., E-mail: tmfiwat@ipc.shizuoka.ac.jp [Faculty of Engineering, Shizuoka University, Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Research Institute of Electronics, Shizuoka University, Johoku, Naka-ku, Hamamatsu 432-8011 (Japan); Ohashi, Y.; Ishisaki, I. [Faculty of Engineering, Shizuoka University, Johoku, Naka-ku, Hamamatsu 432-8561 (Japan); Picco, L.M. [H Will Physics Laboratory and IRC in Nanotechnology, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Ushiki, T. [Graduate School of Medical and Dental Sciences, Niigata University, Asahimachidori, Niigata, 951-8122 (Japan)

    2013-10-15

    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.

  16. 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.

  17. Vertical and lateral forces between a permanent magnet and a high-temperature superconductor

    Science.gov (United States)

    Hull, John R.; Cansiz, Ahmet

    1999-12-01

    The vertical and horizontal forces and associated stiffnesses on a permanent magnet (PM) above a high-temperature superconductor (HTS) were measured during vertical and horizontal traverses in zero-field cooling (ZFC) and in field cooling (FC). In ZFC, the vertical stiffness was greater in the first descent than in the first ascent and second descent, and the stiffness in the second descent was between those of the first descent and the first ascent. At the FC position, the vertical stiffness was two times greater than the lateral stiffness at each height, to within 1% of the vertical stiffness value. The cross stiffness of vertical force with respect to lateral position was positive for FC, but negative for ZFC. Free-spin-down experiments of a PM levitated above a HTS were also performed. These results showed that the coefficient of friction is double valued at frequencies just below the rotor resonance, a result attributed to cross stiffness in the PM/HTS interaction. A frozen-image model was used to calculate the vertical and horizontal forces and stiffnesses, and reasonable agreement with the data occurred for vertical or horizontal movements of the PM less than several mm from the FC position.

  18. A broadband x-ray imaging spectroscopy with high-angular resolution: the FORCE mission

    Science.gov (United States)

    Mori, Koji; Tsuru, Takeshi Go; Nakazawa, Kazuhiro; Ueda, Yoshihiro; Okajima, Takashi; Murakami, Hiroshi; Awaki, Hisamitsu; Matsumoto, Hironori; Fukazawa, Yasushi; Tsunemi, Hiroshi; Takahashi, Tadayuki; Zhang, William W.

    2016-07-01

    We are proposing FORCE (Focusing On Relativistic universe and Cosmic Evolution) as a future Japan-lead Xray observatory to be launched in the mid 2020s. Hitomi (ASTRO-H) possesses a suite of sensitive instruments enabling the highest energy-resolution spectroscopy in soft X-ray band, a broadband X-ray imaging spectroscopy in soft and hard X-ray bands, and further high energy coverage up to soft gamma-ray band. FORCE is the direct successor to the broadband X-ray imaging spectroscopy aspect of Hitomi (ASTRO-H) with significantly higher angular resolution. The current design of FORCE defines energy band pass of 1-80 keV with angular resolution of black holes" in various mass-scales: "buried supermassive black holes (SMBHs)" (> 104 M⊙) residing in the center of galaxies in a cosmological distance, "intermediate-mass black holes" (102-104 M⊙) acting as the possible seeds from which SMBHs grow, and "orphan stellar-mass black holes" (mirror and wide-band X-ray detector. The focal length is currently planned to be 10 m. The silicon mirror with multi-layer coating is our primary choice to achieve lightweight, good angular optics. The detector is a descendant of hard X-ray imager onboard Hitomi (ASTRO-H) replacing its silicon strip detector with SOI-CMOS silicon pixel detector, allowing an extension of the low energy threshold down to 1 keV or even less.

  19. Atomic force microscopy with nanoelectrode tips for high resolution electrochemical, nanoadhesion and nanoelectrical imaging

    Science.gov (United States)

    Nellist, Michael R.; Chen, Yikai; Mark, Andreas; Gödrich, Sebastian; Stelling, Christian; Jiang, Jingjing; Poddar, Rakesh; Li, Chunzeng; Kumar, Ravi; Papastavrou, Georg; Retsch, Markus; Brunschwig, Bruce S.; Huang, Zhuangqun; Xiang, Chengxiang; Boettcher, Shannon W.

    2017-03-01

    Multimodal nano-imaging in electrochemical environments is important across many areas of science and technology. Here, scanning electrochemical microscopy (SECM) using an atomic force microscope (AFM) platform with a nanoelectrode probe is reported. In combination with PeakForce tapping AFM mode, the simultaneous characterization of surface topography, quantitative nanomechanics, nanoelectronic properties, and electrochemical activity is demonstrated. The nanoelectrode probe is coated with dielectric materials and has an exposed conical Pt tip apex of ∼200 nm in height and of ∼25 nm in end-tip radius. These characteristic dimensions permit sub-100 nm spatial resolution for electrochemical imaging. With this nanoelectrode probe we have extended AFM-based nanoelectrical measurements to liquid environments. Experimental data and numerical simulations are used to understand the response of the nanoelectrode probe. With PeakForce SECM, we successfully characterized a surface defect on a highly-oriented pyrolytic graphite electrode showing correlated topographical, electrochemical and nanomechanical information at the highest AFM-SECM resolution. The SECM nanoelectrode also enabled the measurement of heterogeneous electrical conductivity of electrode surfaces in liquid. These studies extend the basic understanding of heterogeneity on graphite/graphene surfaces for electrochemical applications.

  20. Facile preparation of superhydrophobic surface with high adhesive forces based carbon/silica composite films

    Indian Academy of Sciences (India)

    Ruanbing Hu; Guohua Jiang; Xiaohong Wang; Xiaoguang Xi; Rijing Wang

    2013-11-01

    Glass substrates modified by carbon/silica composites are fabricated through a two-step process for the preparation of a superhydrophobic surface (water contact angle ≥ 150°). Carbon nanoparticles were first prepared through a deposition process on glass using a hydrothermal synthesis route, then the glass was modified by SiO2 using the hydrolysis reaction of tetraethylorthosilicate at room temperature. It is not only a facile method to create a superhydrophobic surface, but also helps to form a multi-functional surface with high adhesive forces.

  1. Joining Forces: Collaborating Internationally to Deliver High-Quality, Online Postgraduate Education in Pain Management

    Directory of Open Access Journals (Sweden)

    Elizabeth Devonshire

    2011-01-01

    Full Text Available 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.

  2. Wide-area scanner for high-speed atomic force microscopy

    OpenAIRE

    Watanabe, Hiroki; Uchihashi, Takayuki; Kobashi, Toshihide; Shibata, Mikihiro; Nishiyama, Jun; Yasuda, Ryohei; Ando, Toshio

    2013-01-01

    High-speed atomic force microscopy (HS-AFM) has recently been established. The dynamic processes and structural dynamics of protein molecules in action have been successfully visualized using HS-AFM. However, its maximum scan ranges in the X- and Y-directions have been limited to ∼1 μm and ∼4 μm, respectively, making it infeasible to observe the dynamics of much larger samples, including live cells. Here, we develop a wide-area scanner with a maximum XY scan range of ∼46 × 46 μm2 by magnifyin...

  3. Influence of the lateral movement on the levitation and guidance force in the high-temperature superconductor maglev system

    Science.gov (United States)

    Song, Honghai; de Haas, Oliver; Beyer, Christoph; Krabbes, Gernot; Verges, Peter; Schultz, Ludwig

    2005-05-01

    After the levitation force relaxation was studied for different field-cooling height and working-levitation height, the high-temperature superconductor (HTS) bulk was horizontally moved in the lateral direction above the permanent magnet guideway. Both levitation and guidance force were collected by the measurement system at the same time. It was found that the decay of levitation force is dependent on both the maximum lateral displacement and the movement cycle times, while the guidance force hysteresis curve does not change after the first cycle. This work provided scientific analysis for the HTS maglev system design.

  4. 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…

  5. [Spider bites: araneidism of medical importance].

    Science.gov (United States)

    Pommier, Philip; Rollard, Christine; De Haro, Luc

    2005-01-15

    LIMITED RISKS: Although most species of spiders are venomous, only ten or so are able to induce human envenomations. From a systematic point of view, it is possible to distinguish the araneomorph spiders - or "true" spiders - from the mygalomorph spiders. Dangerous species for humans can be found in both groups. Regarding "true' spiders, two kinds of envenomation are frequent, ubiquitous and potentially severe: latrodectism (neurotoxic symptomatology) due to the Widow spiders of the Latrodectus species,and loxoscelism (viscero-cutaneous symptomatology). Regarding the mygalomorph spiders, the Australian species responsible for atraxism (neurotoxic symptomatology) are considered as the most dangerous. Most of the other mygalomorph spiders, when they bite, only provoke benign loco regional problems. A supplementary defensive weapon exists in certain South-American species: urticating hairs which may induce severe ocular damage.

  6. Slow Death by Many Mosquito Bites

    CERN Document Server

    Redner, S

    2014-01-01

    We study the dynamics of a single diffusing particle (a "man") with diffusivity $D_M$ that is attacked by another diffusing particle (a "mosquito") with fixed diffusivity $D_m$. Each time the mosquito meets and bites the man, the diffusivity of the man is reduced by a fixed amount, while the diffusivity of the mosquito is unchanged. The mosquito is also displaced by a small distance $\\pm a$ with respect to the man after each encounter. The man is defined as dead when $D_M$ reaches zero. At the moment when the man dies, his probability distribution of displacements $x$ is given by a Cauchy form, which asymptotically decays as $x^{-2}$, while the distribution of times $t$ when the man dies asymptotically decays as $t^{-3/2}$, which has the same form as the one-dimensional first-passage probability.

  7. RETROSPECTIV E S TUDY OF DOG BITE CAS ES REPORTED TO ZONAL VETERINARY CLINIC, UMUAHIA, ABIA STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    Mshelbwala PP

    2013-09-01

    Full Text Available A ten year retrospective study of dog bite cases reported to Zonal Veterinary Clinic, Umuahia, Abia State, Nigeria was undertaken, to understand the pattern of occurrence of dog bite in relation to rabies cases in the region. A total of one hundred and ten (110 cases of dog bites were reported during a period of ten years, between January 2004 and June 2013. Out of these 110 dog bite cases, ninety (81.8% persons were bitten by owned dogs, while (18.2% were bitten by stray dogs. Among these 110 50 (45.4% dogs had no anti - rabies vaccination history, 43(39.1% had unknown vaccination status, 7(6.4% had their v accination expired and only 10 (9.1% had current vaccination history. From the clinical signs shown, 6% of the dogs were suspected to be rabid although no confirmatory diagnosis was made. About 71.8% of the victims were adults while 28.2% were children. 5 3. 6% were male and 46.4% female. While dog bite cases were seen more in children in many studies, in this present study more cases were seen in adults. Survey of rabies in dogs and other animals is highly recommended in this study area

  8. Forced canonical thermalization in a hadronic transport approach at high density

    Science.gov (United States)

    Oliinychenko, Dmytro; Petersen, Hannah

    2017-03-01

    Hadronic transport approaches based on an effective solution of the relativistic Boltzmann equation are widely applied for the dynamical description of heavy ion reactions at low beam energies. At high densities, the assumption of binary interactions often used in hadronic transport approaches may not be applicable anymore. Therefore, we effectively simulate the high-density regime using the local forced canonical thermalization. This framework provides the opportunity to interpolate in a dynamical way between two different limits of kinetic theory: the dilute gas approximation and the ideal fluid case. This approach will be important for studies of the dynamical evolution of heavy ion collisions at low and intermediate energies as experimentally investigated at the beam energy scan program at RHIC, and in the future at FAIR and NICA. On the other hand, this new way of modeling hot and dense strongly interacting matter might be relevant for small systems at high energies (LHC and RHIC) as well.

  9. 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.

  10. Analysis of 4-Year Dog-Bite Cases Treated At Ahmadu Bello University Health Centre, Zaria, Nigeria

    Directory of Open Access Journals (Sweden)

    Istifanus Anekoson Joshua

    2012-12-01

    Full Text Available AIM: Rabies is one of the most typical zoonosis; the disease is endemic in Nigeria and remains an important public health issue. The disease is transmitted mainly through the bite of rabid animal and dog is very important because of the close relationship between humans and dogs. The aim of the study was to analyze the 4 year dog bite cases treated at Ahmadu Bello University (ABU Medical Centre (UHC Zaria, Nigeria. METHOD: A longitudinal study was conducted between 2008 and 2011. Relevant information were obtained using structured questionnaire, interview and participant’s observation was used to study the ecology of the dogs. The medical and veterinary doctors were involved in the collection of the information. Data were analyzed with the aid of SPSS Version 17.0 and Chi square statistics was used to test for significance of association at P< 0.05. RESULTS: A total of 132 cases of dog bite were recorded for the period of the study. Majority (35.4% of the victims of the bite were within the age bracket of 1-10 years (mean age 25± 1.7 years, minimum age - 1 year and maximum age- 68 years, male: female ratio 1: 1.9 , 43.6% were staff family, The most common site of the bites was leg (35.2%. First aid treatment given to the victims before presentation at the hospital, were inadequate. Sixty (45.5% of the victims were given treatment against rabies. 63.6% of the dogs involved in the biting were aged 1-4 years, 55% were not vaccinated against rabies, 81.8% were local breed of dog, 13.6% were stray dogs and the most common likely cause of the bites was provocation (54.5%. CONCLUSION: Dog bite is a common medical condition seen in UHC, ABU Zaria. Factors such as poor vaccination of dogs by owners, high proportion of stray dogs, and poor first aid treatment of dog bite injuries, among others are of public health importance. There is need for intensive public enlightenment. [TAF Prev Med Bull 2012; 11(6.000: 661-666

  11. Traumatic Amputation of Finger From an Alligator Snapping Turtle Bite.

    Science.gov (United States)

    Johnson, Robert D; Nielsen, Cynthia L

    2016-06-01

    Legend states that the alligator snapping turtle (Macrochelys temminckii) should be handled with extreme caution as it has jaw strength powerful enough to bite a wooden broomstick in half. Tales of bite injuries from what is the largest freshwater turtle in North America exist anecdotally, yet there are few descriptions of medical encounters for such. The risk of infection from reptilian bites to the hand in an aquatic environment warrants thorough antibiotic treatment in conjunction with hand surgery consultation. We present the first case report of a near total amputation of an index finger in an adolescent boy who had been bitten by a wild "gator snapper."

  12. Accidental hypothermia and frost-bite in Antarctica.

    Science.gov (United States)

    Sullivan, P G

    1987-02-02

    Two members of an Australian Antarctic expedition suffered hypothermia and frost-bite when they were stranded onshore after their small boat was swamped. Their efforts at field survival until recovery, six hours later, are described. At rescue one patient was found to have frost-bite and a core temperature of 30 degrees C. He was treated successfully by rapid rewarming in a hot bath. The other victim was considerably less hypothermic and suffered only mild frost-bite. Contrary to expectations the tall thin patient fared much better than the short heavier one. Possible explanations for this difference are discussed.

  13. Brown recluse spider bite to the upper lip.

    Science.gov (United States)

    Dare, Ryan K; Conner, Kelly B; Tan, Poliana C; Hopkins, Robert H

    2012-03-01

    Brown recluse spiders are predominantly found in south central United States. Their bites usually cause mild self-limiting reactions, although localized tissue necrosis and rare systemic, potentially fatal, envenomations are known to occur. Herein, we report an atypical presentation of a brown recluse bite in a 20 year old female who was admitted to the intensive care unit due to angioedema and cellulitis. We photographically document the bite site for twenty-four hours following envenomation. She received glucocorticoids, antihistamines, antibiotics and dapsone while hospitalized and was subsequently discharged with complete resolution of symptoms without the development of tissue necrosis or scarring.

  14. High g-Force Rollercoaster Rides Induce Sinus Tachycardia but No Cardiac Arrhythmias in Healthy Children.

    Science.gov (United States)

    Pieles, Guido E; Husk, Victoria; Blackwell, Teresa; Wilson, Deirdre; Collin, Simon M; Williams, Craig A; Stuart, A Graham

    2017-01-01

    Theme park operators and medical professionals advise children with heart conditions against using rollercoaster rides, but these recommendations are not evidence-based. The underlying assumption is that the combination of adrenergic stimulation through stress and acceleration might trigger arrhythmias in susceptible individuals. We conducted a cross-sectional observational study to assess heart rate and rhythm in healthy children during commercial rollercoaster rides. Twenty healthy children (9 male) aged 11-15 (mean 13.3 ± 1.4) years underwent continuous heart rate and rhythm monitoring (2-lead ECG) from 5 min before until 10 min after each of 4 high speed (>50 km h(-1)), high g-force (>4) commercial rollercoaster rides. Total recording time was 13 h 20 min. No arrhythmic events were detected. Resting heart rate was 81 ± 10 b min(-1) and increased to 158 ± 20 b·min(-1) during rides. The highest mean HR (165 ± 23 b min(-1)) was observed on the ride with the lowest g-force (4.5 g), but one of the highest speeds (100 km h(-1)). Anticipatory tachycardia (126 ± 15 b min(-1)) within 5 min was frequently observed. A 10 min recovery HR (124 ± 17 b min(-1)) was 56 % greater than resting HR. The speed and g-force experienced on roller coasters induce sinus tachycardia but do not elicit pathological arrhythmias in healthy children.

  15. 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.

  16. 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.

  17. Atomic ordering in cubic bismuth telluride alloy phases at high pressure

    Science.gov (United States)

    Loa, I.; Bos, J.-W. G.; Downie, R. A.; Syassen, K.

    2016-06-01

    Pressure-induced transitions from ordered intermetallic phases to substitutional alloys to semi-ordered phases were studied in a series of bismuth tellurides. By using angle-dispersive x-ray diffraction, the compounds Bi4Te5 , BiTe, and Bi2Te were observed to form alloys with the disordered body-centered cubic (bcc) crystal structure upon compression to above 14-19 GPa at room temperature. The BiTe and Bi2Te alloys and the previously discovered high-pressure alloys of Bi2Te3 and Bi4Te3 were all found to show atomic ordering after gentle annealing at very moderate temperatures of ˜100 ∘C . Upon annealing, BiTe transforms from bcc to the B2 (CsCl) crystal-structure type, and the other phases adopt semi-disordered variants thereof, featuring substitutional disorder on one of the two crystallographic sites. The transition pressures and atomic volumes of the alloy phases show systematic variations across the BimTen series including the end members Bi and Te. First-principles calculations were performed to characterize the electronic structure and chemical bonding properties of B2-type BiTe and to identify the driving forces of the ordering transition. The calculated Fermi surface of B2-type BiTe has an intricate structure and is predicted to undergo three topological changes between 20 and 60 GPa.

  18. Cutting force and its frequency spectrum characteristics in high speed milling of titanium alloy with a polycrystalline diamond tool

    Institute of Scientific and Technical Information of China (English)

    Peng LIU; Jiu-hua XU; Yu-can FU

    2011-01-01

    In this paper, a series of experiments were performed by high speed milling of Ti-6.5Al-2Zr-1Mo-1V(TA15)by use of polycrystalline diamond(PCD)tools. The characteristics of high speed machining(HSM)dynamic milling forces were investigated. The effects of the parameters of the process, I.e., cutting speed, feed per tooth, and depth of axial cut, on cutting forces were studied. The cutting force signals under different cutting speed conditions and different cutting tool wear stages were analyzed by frequency spectrum analysis. The trend and frequency domain aspects of the dynamic forces were evaluated and discussed. The results indicate that a characteristic frequency in cutting force power spectrum does in fact exist. The amplitudes increase with the increase of cutting speed and tool wear level, which could be applied to the monitoring of the cutting process.

  19. Synthesis of one-molecule-thick single-crystalline nanosheets of energetic material for high-sensitive force sensor.

    Science.gov (United States)

    Yang, Guangcheng; Hu, Hailong; Zhou, Yong; Hu, Yingjie; Huang, Hui; Nie, Fude; Shi, Weimei

    2012-01-01

    Energetic material is a reactive substance that contains a great amount of potential energy, which is extremely sensitive to external stimuli like force. In this work, one-molecule-thick single-crystalline nanosheets of energetic material were synthesized. Very small force applied on the nanosheet proves to lead to the rotation of the tilted nitro groups, and subsequently change of current of the nanosheet. We apply this principle to design high-sensitive force sensor. A theoretical model of force-current dependence was established based on the nanosheets' molecular packing structure model that was well supported with the high resolution XPS, AFM analysis results. An ultra-low-force with range of several picoNewton to several nanoNewton can be measured by determination of corresponding current value.

  20. From eggs to bites: do ovitrap data provide reliable estimates of Aedes albopictus biting females?

    Directory of Open Access Journals (Sweden)

    Mattia Manica

    2017-03-01

    Full Text Available Background Aedes albopictus is an aggressive invasive mosquito species that represents a serious health concern not only in tropical areas, but also in temperate regions due to its role as vector of arboviruses. Estimates of mosquito biting rates are essential to account for vector-human contact in models aimed to predict the risk of arbovirus autochthonous transmission and outbreaks, as well as nuisance thresholds useful for correct planning of mosquito control interventions. Methods targeting daytime and outdoor biting Ae. albopictus females (e.g., Human Landing Collection, HLC are expensive and difficult to implement in large scale schemes. Instead, egg-collections by ovitraps are the most widely used routine approach for large-scale monitoring of the species. The aim of this work was to assess whether ovitrap data can be exploited to estimate numbers of adult biting Ae. albopictus females and whether the resulting relationship could be used to build risk models helpful for decision-makers in charge of planning of mosquito-control activities in infested areas. Method Ovitrap collections and HLCs were carried out in hot-spots of Ae. albopictus abundance in Rome (Italy along a whole reproductive season. The relationship between the two sets of data was assessed by generalized least square analysis, taking into account meteorological parameters. Result The mean number of mosquito females/person collected by HLC in 15′ (i.e., females/HLC and the mean number of eggs/day were 18.9 ± 0.7 and 39.0 ± 2.0, respectively. The regression models found a significant positive relationship between the two sets of data and estimated an increase of one biting female/person every five additional eggs found in ovitraps. Both observed and fitted values indicated presence of adults in the absence of eggs in ovitraps. Notably, wide confidence intervals of estimates of biting females based on eggs were observed. The patterns of exotic arbovirus outbreak

  1. From eggs to bites: do ovitrap data provide reliable estimates of Aedes albopictus biting females?

    Science.gov (United States)

    Manica, Mattia; Rosà, Roberto; Della Torre, Alessandra; Caputo, Beniamino

    2017-01-01

    Aedes albopictus is an aggressive invasive mosquito species that represents a serious health concern not only in tropical areas, but also in temperate regions due to its role as vector of arboviruses. Estimates of mosquito biting rates are essential to account for vector-human contact in models aimed to predict the risk of arbovirus autochthonous transmission and outbreaks, as well as nuisance thresholds useful for correct planning of mosquito control interventions. Methods targeting daytime and outdoor biting Ae. albopictus females (e.g., Human Landing Collection, HLC) are expensive and difficult to implement in large scale schemes. Instead, egg-collections by ovitraps are the most widely used routine approach for large-scale monitoring of the species. The aim of this work was to assess whether ovitrap data can be exploited to estimate numbers of adult biting Ae. albopictus females and whether the resulting relationship could be used to build risk models helpful for decision-makers in charge of planning of mosquito-control activities in infested areas. Ovitrap collections and HLCs were carried out in hot-spots of Ae. albopictus abundance in Rome (Italy) along a whole reproductive season. The relationship between the two sets of data was assessed by generalized least square analysis, taking into account meteorological parameters. The mean number of mosquito females/person collected by HLC in 15' (i.e., females/HLC) and the mean number of eggs/day were 18.9 ± 0.7 and 39.0 ± 2.0, respectively. The regression models found a significant positive relationship between the two sets of data and estimated an increase of one biting female/person every five additional eggs found in ovitraps. Both observed and fitted values indicated presence of adults in the absence of eggs in ovitraps. Notably, wide confidence intervals of estimates of biting females based on eggs were observed. The patterns of exotic arbovirus outbreak probability obtained by introducing these estimates

  2. From eggs to bites: do ovitrap data provide reliable estimates of Aedes albopictus biting females?

    Science.gov (United States)

    Manica, Mattia; Rosà, Roberto; della Torre, Alessandra

    2017-01-01

    Background Aedes albopictus is an aggressive invasive mosquito species that represents a serious health concern not only in tropical areas, but also in temperate regions due to its role as vector of arboviruses. Estimates of mosquito biting rates are essential to account for vector-human contact in models aimed to predict the risk of arbovirus autochthonous transmission and outbreaks, as well as nuisance thresholds useful for correct planning of mosquito control interventions. Methods targeting daytime and outdoor biting Ae. albopictus females (e.g., Human Landing Collection, HLC) are expensive and difficult to implement in large scale schemes. Instead, egg-collections by ovitraps are the most widely used routine approach for large-scale monitoring of the species. The aim of this work was to assess whether ovitrap data can be exploited to estimate numbers of adult biting Ae. albopictus females and whether the resulting relationship could be used to build risk models helpful for decision-makers in charge of planning of mosquito-control activities in infested areas. Method Ovitrap collections and HLCs were carried out in hot-spots of Ae. albopictus abundance in Rome (Italy) along a whole reproductive season. The relationship between the two sets of data was assessed by generalized least square analysis, taking into account meteorological parameters. Result The mean number of mosquito females/person collected by HLC in 15′ (i.e., females/HLC) and the mean number of eggs/day were 18.9 ± 0.7 and 39.0 ± 2.0, respectively. The regression models found a significant positive relationship between the two sets of data and estimated an increase of one biting female/person every five additional eggs found in ovitraps. Both observed and fitted values indicated presence of adults in the absence of eggs in ovitraps. Notably, wide confidence intervals of estimates of biting females based on eggs were observed. The patterns of exotic arbovirus outbreak probability obtained by

  3. Evaluation and optimization of quartz resonant-frequency retuned fork force sensors with high Q factors, and the associated electric circuits, for non-contact atomic force microscopy.

    Science.gov (United States)

    Ooe, Hiroaki; Fujii, Mikihiro; Tomitori, Masahiko; Arai, Toyoko

    2016-02-01

    High-Q factor retuned fork (RTF) force sensors made from quartz tuning forks, and the electric circuits for the sensors, were evaluated and optimized to improve the performance of non-contact atomic force microscopy (nc-AFM) performed under ultrahigh vacuum (UHV) conditions. To exploit the high Q factor of the RTF sensor, the oscillation of the RTF sensor was excited at its resonant frequency, using a stray capacitance compensation circuit to cancel the excitation signal leaked through the stray capacitor of the sensor. To improve the signal-to-noise (S/N) ratio in the detected signal, a small capacitor was inserted before the input of an operational (OP) amplifier placed in an UHV chamber, which reduced the output noise from the amplifier. A low-noise, wideband OP amplifier produced a superior S/N ratio, compared with a precision OP amplifier. The thermal vibrational density spectra of the RTF sensors were evaluated using the circuit. The RTF sensor with an effective spring constant value as low as 1000 N/m provided a lower minimum detection limit for force differentiation. A nc-AFM image of a Si(111)-7 × 7 surface was produced with atomic resolution using the RTF sensor in a constant frequency shift mode; tunneling current and energy dissipation images with atomic resolution were also simultaneously produced. The high-Q factor RTF sensor showed potential for the high sensitivity of energy dissipation as small as 1 meV/cycle and the high-resolution analysis of non-conservative force interactions.

  4. Novel Crossing System for Chronic Total Occlusion Recanalization: First-in-Man Experience With the SoundBite Crossing System.

    Science.gov (United States)

    Benko, Andrew; Bérubé, Simon; Buller, Christopher E; Dion, Steven; Riel, Louis-Philippe; Brouillette, Martin; Généreux, Philippe

    2017-02-01

    Chronic total occlusion (CTO) lesions are frequent in patients with peripheral and coronary artery disease, and are associated with a higher risk of adverse events, including mortality, decreased quality of life, and increased health-care costs. Percutaneous intervention of CTO lesions has been associated with a lower procedural success rate, and current dedicated CTO devices may be of limited use for non-CTO experts, and associated with increased intraprocedural complication rates. The SoundBite Crossing System (SoundBite Medical Solutions, Inc) is a newly-developed device using shockwaves (short-duration, high-amplitude pressure pulses) delivered to the tip of guidewire to facilitate penetration of the proximal cap and crossing of the occlusion. The current report describes the first-in-man use of the SoundBite Crossing System in the recanalization of two occluded lower-limb arteries.

  5. High Speed Photography, Videography, And Photonic Instrumentation Development At The Air Force Armament Laboratory

    Science.gov (United States)

    Snyder, Donald R.; Powell, Rodney M.

    1989-02-01

    The Instrumentation Technology Branch of the Air Force Armament Laboratory is currently involved in the development of several high speed photographic, videographic, and photonic instrumentation systems to support the testing and analysis of developmental weapons and test items under dynamic conditions. These projects include development of a large format (14 inch by 17 inch) laser illuminated Cranz-Schardin shadowgraph system for materials research, development of a solid state imager based shadowgraph system for aeroballistic studies, experiments with gated imagers for a variety of test applications, and experiments with high speed video imagers and illuminators for airborne and range tracking instrumentation. An additional issue discussed is the development of a timing and annotation standard for video imaging instrumentation systems operating at higher than NTSC standard rates.

  6. 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.

  7. Dynamics of highly-flexible solar sail subjected to various forces

    Science.gov (United States)

    Liu, Jiafu; Cui, Naigang; Shen, Fan; Rong, Siyuan

    2014-10-01

    Solar sail is a novel spacecraft and has the potential applications in the near future. The large amplitude vibration should be considered because it is characterized by its huge and lightweight structure. In this paper, the supporting beam of solar sail is regarded as the most important structure and used to model the sailcraft as it accounts for most of the mechanical energies when it is in deformed configuration, also as the Euler beam can model the bending motion dominant sailcraft when it experiences attitude motions. The structural dynamics of solar sail supporting beam with geometric nonlinearity undergoing the forces generated by solar radiation pressure, sliding masses and control vanes are presented. The axial and transverse vibration equations with the properties of strong coupling, nonlinearity and time-varying coefficient matrices are obtained by using Lagrange equation method after calculating the related energies and works. The vibration equations are transformed into nonlinear algebraic equations utilizing implicit unconditionally stable Newmark-β algorithm for each time step. The nonlinear algebraic equations are solved by Newton-iterative algorithm. We compute and analyze the linear and nonlinear vibration responses affected by the mass and velocity of the sliding mass, the angular velocity of the force generated by control vane in detail. The computational results indicate that the mass and velocity of sliding mass affect the vibration responses (including the vibration frequency), but the angular velocity of the force generated by control vane hardly affects the vibration responses. Moreover, the linear and nonlinear vibrations are distinct obviously by comparing the linear and nonlinear responses. It is demonstrated that the geometric nonlinearity of the highly-flexible structure should be considered for performing vibration analysis exactly, and the vibration responses excited by the prescribed motion of the attitude control actuators should

  8. Effect of high-intensity interval training on cardiovascular function, VO2max, and muscular force.

    Science.gov (United States)

    Astorino, Todd A; Allen, Ryan P; Roberson, Daniel W; Jurancich, Matt

    2012-01-01

    The purpose of this study was to examine the effects of short-term high-intensity interval training (HIIT) on cardiovascular function, cardiorespiratory fitness, and muscular force. Active, young (age and body fat = 25.3 ± 4.5 years and 14.3 ± 6.4%) men and women (N = 20) of a similar age, physical activity, and maximal oxygen uptake (VO2max) completed 6 sessions of HIIT consisting of repeated Wingate tests over a 2- to 3-week period. Subjects completed 4 Wingate tests on days 1 and 2, 5 on days 3 and 4, and 6 on days 5 and 6. A control group of 9 men and women (age and body fat = 22.8 ± 2.8 years and 15.2 ± 6.9%) completed all testing but did not perform HIIT. Changes in resting blood pressure (BP) and heart rate (HR), VO2max, body composition, oxygen (O2) pulse, peak, mean, and minimum power output, fatigue index, and voluntary force production of the knee flexors and extensors were examined pretraining and posttraining. Results showed significant (p VO2max, O2 pulse, and Wingate-derived power output with HIIT. The magnitude of improvement in VO2max was related to baseline VO2max (r = -0.44, p = 0.05) and fatigue index (r = 0.50, p 0.05) in resting BP, HR, or force production was revealed. Data show that HIIT significantly enhanced VO2max and O2 pulse and power output in active men and women.

  9. SIMULATION STUDY OF AERODYNAMIC FORCE FOR HIGH-SPEED MAGNETICALLY-LEVITATED TRAINS

    Institute of Scientific and Technical Information of China (English)

    LI Renxian; LIU Yingqing; ZHAI Wanming

    2006-01-01

    Based on Reynolds average Navier-Storkes equations of viscous incompressible fluid and k-ε two equations turbulent model, the aerodynamic forces of high-speed magnetically-levitated(maglev) trains in transverse and longitudinal wind are investigated by finite volume method. Near 80 calculation cases for 2D transverse wind fields and 20 cases for 3D longitudinal wind fields are and lyzed. The aerodynamic side force, yawing, drag, lift and pitching moment for different types of maglev trains and a wheel/rail train are compared under the different wind speeds. The types of maglev train models for 2D transverse wind analysis included electromagnetic suspension (EMS) type train,electrodynamic suspension (EDS) type train, EMS type train with shelter wind wall in one side or two sides of guideway and the walls, which are in different height or/and different distances from train body. The situation of maglev train running on viaduct is also analyzed. For 3D longitudinal wind field analysis, the model with different sizes of air clearances beneath maglev train is examined for the different speeds. Calculation result shows that: ① Different transverse effects are shown in different types of maglev trains. ② The shelter wind wall can fairly decrease the transverse effect on the maglev train. ③ When the shelter wall height is 2 m, there is minimum side force on the train.When the shelter wall height is 2.5 m, there is minimum yawing moment on the train. ④ When the distance between inside surfaces of the walls and center of guideway is 4.0 m, there is minimum transverse influence on the train. ⑤ The size of air clearance beneath train body has a small influence on aerodynamic drag of the train, but has a fairly large effect on aerodynamic lift and pitching moment of the train. ⑥ The calculating lift and pitching moment for maglev train models are minus values.

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

    Medline Plus

    Full Text Available ... care Younger skin 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 ...

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

    Medline Plus

    Full Text Available ... MOC webinars and videos FAQs MOC resources 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 ...

  12. Two cases of viper bite: still an important health problem

    Directory of Open Access Journals (Sweden)

    Adrija Hajra

    2016-04-01

    Full Text Available Viper venoms act mainly as hemotoxic. Manifestations of snakebites depend on specific toxins that constitute the venom. The local and systemic snake bite related symptoms are directly linked to the toxicity of the venom. Edema, ecchymoses, hematoma, and gangrenous lesions are reported to occur as local symptoms. Systemic symptoms may include fever, nausea, vomiting, delirium, jaundice, circulatory collapse, convulsions, and coma. Death from secondary infections, neurotoxicity, disseminated intravascular coagulation (DIC, intracranial hemorrhage, and acute renal failure are the well-known facts. For reduction of morbidity and mortality, it is important that antiserum is administered at the appropriate dose as early as possible after snake bite. There are several case reports about various complications of viperid bite. Here we are discussing two cases of viper bite. These cases are unique because of the extensive tissue necrosis. One of them succumbed to septicemia after acute pancreatitis. [Int J Res Med Sci 2016; 4(4.000: 1274-1277

  13. "Fight-bite": not just a hand problem.

    Science.gov (United States)

    Cook, C P T Jay B; Knox, Maj Jeffrey B; Wimberly, Robert L; Ellis, Henry B; Riccio, Anthony I

    2014-09-01

    Human bite wounds around the knee are rarely seen, yet may require the same urgent attention as a fight bite to the hand. Two cases of polymicrobial septic arthritis of the knee secondary to a human bite wound are described. In both the cases, the diagnosis of the septic arthritis was delayed because the intra-articular wound was unrecognized. The injuries were initially deemed superficial and managed with local wound care. In each case, the knee was flexed at the time of injury and the quadriceps tendon was penetrated by a tooth which inoculated the knee joint. Septic arthritis of the knee presented, in both cases, 72 hours after the injury. These infections proved challenging to treat and required multiple surgeries and prolonged antibiotic therapy. The "fight bite" phenomenon of the hand is widely recognized and the same phenomenon can occur at the knee.

  14. 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 ...

  15. 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= ...

  16. New Mexico rattlesnake bites: demographic review and guidelines for treatment.

    Science.gov (United States)

    Downey, D J; Omer, G E; Moneim, M S

    1991-10-01

    The demographic features, treatment, and outcome of 36 rattlesnake envenomation cases are reviewed. Two populations at special risk are identified: (1) young children (12/36) who sustain lower extremity bites, and (2) adults who consume alcohol and handle snakes (10/36) who sustain upper extremity bites. Antivenin was used in 22 cases with only one serious case of serum sickness. Three definite diagnoses of compartment syndrome were made on the basis of elevated compartment pressures. Hand bites accounted for 20 of the 36 cases. The greatest functional disability followed digit bites in that 11 patients developed decreased motion and sensation. The indications for fasciotomy and debridement are discussed, both for digit and non-digit envenomations. General treatment recommendations are given.

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

    Medline Plus

    Full Text Available ... order of modules Video library Quiz library Basement Membrane Zone lecture Full lecture Part 1: Structure Part ... Skin care Hair care / hair loss Injured skin Blisters Bug bites and stings How to remove a ...

  18. Risk of Disease from Mosquito and Tick Bites

    Science.gov (United States)

    Insect repellents help reduce the risk of mosquito and tick bites, which can transmit diseases including West Nile Virus, malaria, encephalitis, yellow fever, dengue fever, chikungunya virus, Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis.

  19. Snake bites in Kenya: a preliminary survey of four areas.

    Science.gov (United States)

    Coombs, M D; Dunachie, S J; Brooker, S; Haynes, J; Church, J; Warrell, D A

    1997-01-01

    Primary data were collected on the incidence, severity and species responsible for snake bites in 4 areas of Kenya: (i) Kakamega and western Kenya, (ii) Lake Baringo and Laikipia, (iii) Kilifi and Malindi, and (iv) northern Kenya. The overall average frequency of snake bite was 13.8 per 100,000 population per year (range 1.9-67.9). The minimum rate of snake bite mortality was 0.45/100,000/year. Thirty-four of the 50 units visited reported no knowledge of death from snake bite in the last 5 years. Possible reasons for the low estimates are discussed. Traditional treatments were common, especially the use of herbal remedies and incisions at the wound site.

  20. 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

  1. Independent component analysis of high-density electromyography in muscle force estimation.

    NARCIS (Netherlands)

    Staudenmann, D.; Daffertshofer, A.; Kingma, I.; Stegeman, D.F.; Dieen, J.H. van

    2007-01-01

    Accurate force prediction from surface electromyography (EMG) forms an important methodological challenge in biomechanics and kinesiology. In a previous study (Staudenmann et al., 2006), we illustrated force estimates based on analyses lent from multivariate statistics. In particular, we showed the

  2. Human bite of the hand: clinical and surgical approach

    OpenAIRE

    Simancas-Pereira Hernán; Fonseca-Caro John Fredy; Acevedo-Granados Camilo Andrés

    2012-01-01

    Introduction: human bites of the hand carries a risk of infection and functional and/oraesthetic complications, according to the mechanism of trauma, duration and specificfactors of the victim and the aggressor. The management of acute episodes isessential and must be an interdisciplinary care.Objective: to review human bites of the hand.Methodology: Thematic review which included the evaluation of clinical casereports published in the last fifteen years in English and Spanish, obtained by el...

  3. Black mamba bites. A report of 2 cases.

    Science.gov (United States)

    Hilligan, R

    1987-08-01

    The clinical features of confirmed cases of black mamba snakebites in a 14-month-old child and a 34-year-old man are presented. The steps taken in management are described and reviewed. The importance of early aggressive treatment and general principles of mamba bite management are discussed. To date there has been no reported case of confirmed and medically treated black mamba bite in a child so young.

  4. Inhibitory reflex responses of masseter muscle in anterior open bite

    OpenAIRE

    Priyada, SANTILAKANAWONG; Hiroaki, KIRIMOTO; Yoichiro, SEKI; Kunimichi, SOMA; Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University

    2003-01-01

    Animal studies indicated that loss of occlusal contact between maxillary and mandibular teeth causes altered functional activity of periodontal mechanoreceptors. The alteration of periodontal mechanoreceptors may influence jawmuscle reflex and masticatory muscle activity. In this study, the inhibitory reflex response of masseter muscle in subjects with anterior open bite was investigated. The study population included 10 subjects with anterior open bite with no muscle pain or craniomandibular...

  5. Fatal snake bites – sociodemography, latency pattern of injuries

    Science.gov (United States)

    2013-01-01

    Background India is a thickly populated country; apart from having biodiversity among people, climate does change from place to place. Western Ghats of South India harbors variety of plantations and diverse creatures. Agriculture is the primary occupation of the people and some tribes living in these regions. Here majority are callous/ ignorant in employing neither advanced farming techniques nor safety precautions, hence are exposed to bites and stings by animals. Of these, snake bites cause significant mortality and morbidity. Proper care for some of these individuals is out of reach. Identification of offending snake, snake bite injury or findings of envenomation is a key not only for the administration of antisnake venom but also for the victim to realize that he needs an expert care. Unless he believes it to be a critical snake bite and not a thorn prick, scorpion sting or a spider bite he will not approach a health care provider. To know about these dangerous signs that may help the victim to realize it as a case of snake bite, current study is employed on fatal cases in this region. Methods 60 fatal snakebite cases were studied retrospectively for 5 years with an objective to know the socio-demography, latency and pattern of injuries in rural Southern India. Results Most of the victims were males, in the age group of 31-50 years and were at risk of snake bites while farming. Large sample of subjects approached traditional therapists and were deprived of essential care in the critical first few hours after snake bite. Fang marks (90%), local ecchymoses (50%) and internal hemorrhage (28.3%), were the frequent demonstrable signs appreciated at autopsy. Conclusion Snakebite is a neglected, endemic, occupational (farming) disease of the poor and there is need for National Snakebite Prevention Programme for curtailing this menace. PMID:23522302

  6. Acute generalized exanthematous pustulosis associated with spider bite*

    OpenAIRE

    Milman, Laura de Mattos; Müller,Giana Paula; de Souza, Paulo Ricardo Martins; Grill, Aline Barcellos; Rhoden, Deise Louise Bohn; Mello-da-Silva, Carlos Augusto; Vettorato,Gerson

    2016-01-01

    Abstract: Acute generalized exanthematous pustulosis (AGEP) is an acute febrile rash, usually induced by drugs, which recently has been linked to spider bite. We report a case of a male patient, 48 years old, with an erythematous rash accompanied by fever and small non-follicular pustules. He reported previous pain in the buttock with the onset of a necrotic plaque. The lesion was compatible with spider bite of the genus Loxosceles. According to the EuroSCAR group instrument, the patient scor...

  7. 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.

  8. Suspected dog bite associated HIV horizontal transmission in Swaziland

    Directory of Open Access Journals (Sweden)

    Ganizani Mlawanda

    2013-01-01

    Full Text Available Background: Dog bites may lead to transmission of bacteria and viruses over and above tetanus and rabies. Theoretically human immunodeficiency virus (HIV, Hepatitis B and Hepatitis C may be transmitted after dog bites where transfer of blood from one victim to another occur in clinical practice HIV, Hepatitis B and Hepatitis C are not considered when making treatment decisions, nor adequate patient history taken to consider all potential risks after dog bites in succession.Objective: To present case of suspected HIV transmission after dog bites in close succession involving two HIV sero-discordant victims.Management and outcome: HIV rapid test and/or HIV Ribonucleic acid (RNA polymerasechain reaction (PCR results for the victim(s at presentation and a month later.Results: Two night patrol guards presented to casualty after dog bites in close succession by the same dog. They were managed according to the dog bite protocol. Thinking out of the box, the first victim was found to be HIV positive by rapid test whilst the second victim was negative based on both HIV rapid test and HIV RNA PCR. One month after the dogbites, a case of HIV sero-conversion was confirmed in the second victim despite post-exposure prophylaxis (PEP.Discussion: Although an isolated case, shouldn’t clinicians re-think the significance of HIV transmission after animal bites where there is repeated blood exposure in several people insuccession?Conclusion: Clinicians should be aware of the potential of HIV, Hepatitis B and C transmission, when faced with dog bites in succession. 

  9. Large surface radiative forcing from topographic blowing snow residuals measured in the High Arctic at Eureka

    Directory of Open Access Journals (Sweden)

    G. Lesins

    2009-03-01

    Full Text Available Ice crystals, also known as diamond dust, are suspended in the boundary layer air under clear sky conditions during most of the Arctic winter in Northern Canada. Occasionally ice crystal events can produce significantly thick layers with optical depths in excess of 2.0 even in the absence of liquid water clouds. Four case studies of high optical depth ice crystal events at Eureka in the Nunavut Territory of Canada during the winter of 2006/07 are presented. They show that the measured ice crystal surface infrared downward radiative forcing ranged from 8 to 36 W m−2 in the wavelength band from 5.6 to 20 μm for 532 nm optical depths ranging from 0.2 to 1.7. MODIS infrared and visible images and the operational radiosonde wind profile were used to show that these high optical depth events were caused by surface snow being blown off 600 to 800 m high mountain ridges about 20 to 30 km North-West of Eureka and advected by the winds towards Eureka as they settled towards the ground within the highly stable boundary layer. This work presents the first study that demonstrates the important role that surrounding topography plays in determining the occurrence of high optical depth ice crystal events from residual blowing snow that becomes a source of boundary layer ice crystals distinct from the classical diamond dust phenomenon.

  10. Modeling of stochastic dynamics of time-dependent flows under high-dimensional random forcing

    Science.gov (United States)

    Babaee, Hessam; Karniadakis, George

    2016-11-01

    In this numerical study the effect of high-dimensional stochastic forcing in time-dependent flows is investigated. To efficiently quantify the evolution of stochasticity in such a system, the dynamically orthogonal method is used. In this methodology, the solution is approximated by a generalized Karhunen-Loeve (KL) expansion in the form of u (x , t ω) = u ̲ (x , t) + ∑ i = 1 N yi (t ω)ui (x , t) , in which u ̲ (x , t) is the stochastic mean, the set of ui (x , t) 's is a deterministic orthogonal basis and yi (t ω) 's are the stochastic coefficients. Explicit evolution equations for u ̲ , ui and yi are formulated. The elements of the basis ui (x , t) 's remain orthogonal for all times and they evolve according to the system dynamics to capture the energetically dominant stochastic subspace. We consider two classical fluid dynamics problems: (1) flow over a cylinder, and (2) flow over an airfoil under up to one-hundred dimensional random forcing. We explore the interaction of intrinsic with extrinsic stochasticity in these flows. DARPA N66001-15-2-4055, Office of Naval Research N00014-14-1-0166.

  11. Characterization of the surface charge distribution on kaolinite particles using high resolution atomic force microscopy

    Science.gov (United States)

    Kumar, Naveen; Zhao, Cunlu; Klaassen, Aram; van den Ende, Dirk; Mugele, Frieder; Siretanu, Igor

    2016-02-01

    Most solid surfaces, in particular clay minerals and rock surfaces, acquire a surface charge upon exposure to an aqueous environment due to adsorption and/or desorption of ionic species. Macroscopic techniques such as titration and electrokinetic measurements are commonly used to determine the surface charge and ζ -potential of these surfaces. However, because of the macroscopic averaging character these techniques cannot do justice to the role of local heterogeneities on the surfaces. In this work, we use dynamic atomic force microscopy (AFM) to determine the distribution of surface charge on the two (gibbsite-like and silica-like) basal planes of kaolinite nanoparticles immersed in aqueous electrolyte with a lateral resolution of approximately 30 nm. The surface charge density is extracted from force-distance curves using DLVO theory in combination with surface complexation modeling. While the gibbsite-like and the silica-like facet display on average positive and negative surface charge values as expected, our measurements reveal lateral variations of more than a factor of two on seemingly atomically smooth terraces, even if high resolution AFM images clearly reveal the atomic lattice on the surface. These results suggest that simple surface complexation models of clays that attribute a unique surface chemistry and hence homogeneous surface charge densities to basal planes may miss important aspects of real clay surfaces.

  12. High harmonic interferometry of the Lorentz force in strong mid-infrared laser fields

    CERN Document Server

    Pisanty, Emilio; Galloway, Benjamin R; Durfee, Charles G; Kapteyn, Henry C; Murnane, Margaret M; Ivanov, Misha

    2016-01-01

    The interaction of intense mid-infrared laser fields with atoms and molecules leads to a range of new opportunities, from the production of bright, coherent radiation in the soft x-ray range to imaging molecular structures and dynamics with attosecond temporal and sub-angstrom spatial resolution. However, all these effects, which rely on laser-driven recollision of an electron removed by the strong laser field and the parent ion, suffer from the rapidly increasing role of the magnetic field component of the driving pulse: the associated Lorentz force pushes the electrons off course in their excursion and suppresses all recollision-based processes, including high harmonic generation, elastic and inelastic scattering. Here we show how the use of two non-collinear beams with opposite circular polarizations produces a forwards ellipticity which can be used to monitor, control, and cancel the effect of the Lorentz force. This arrangement can thus be used to re-enable recollision-based phenomena in regimes beyond t...

  13. Design and Analysis of a High Force, Low Voltage and High Flow Rate Electro-Thermal Micropump

    Directory of Open Access Journals (Sweden)

    Ghader Yosefi

    2014-12-01

    Full Text Available This paper presents the design and simulation of an improved electro-thermal micromachined pump for drug delivery applications. Thermal actuators, which are a type of Micro Electro Mechanical system (MEMS device, are highly useful because of their ability to deliver with great force and displacement. Thus, our structure is based on a thermal actuator that exploits the Joule heating effect and has been improved using the springy length properties of MEMS chevron beams. The Joule heating effect results in a difference in temperature and therefore displacement in the beams (actuators. Simulation results show that a maximum force of 4.4 mN and a maximum flow rate of 16 μL/min can be obtained by applying an AC voltage as low as 8 V at different frequencies ranging from 1 to 32 Hz. The maximum temperature was a problem at the chevron beams and the center shaft. Thus, to locally increase the temperature of the chevron beams alone and not that of the pumping diaphragm: (1 The air gaps 2 μm underneath and above the device layer were optimized for heat transfer. (2 Release holes and providing fins were created at the center shaft and actuator, respectively, to decrease the temperature by approximately 10 °C. (3 We inserted and used a polymer tube to serve as an insulator and eliminate leakage problems in the fluidic channel.

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

    OpenAIRE

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

    2017-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Maureen Coetzee

    2017-07-01

    Full Text Available 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.

  16. 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.

  17. A Finger Amputation Case Caused by Human Bite

    Directory of Open Access Journals (Sweden)

    Kamil Hakan Doğan

    2014-07-01

    Full Text Available Bite is a type of wound created with animal or human teeth. Bite wounds created by humans are encountered in situations as fighting, rape, murder and child abuse. Bite marks are usually observed on arms, neck, breasts, body, cheeks and legs. The teeth may penetrate to skin on the areas where bone or cartilage tissue lies underneath skin, and tissue loss may occur. Auricles are most frequent regions that occur tissue loss with bites. Finger amputation occurring with human bite is extremely rare. The case presented in this paper is a 28 years old man. In his medical history, the 3rd finger of his left hand was bitten during a fight two months ago. One centimeter shortness at the end point of the distal phalanx of the left 3rd finger because of tissue loss was found in the examination. In his left hand radiograph, bone defect at the middle part of the distal phalanx of 3rd finger was determined. The case has been discussed by comparing similar cases rarely reported in the literature. Keywords: Forensic medicine, human bite, amputation

  18. A comparison of animal jaws and bite mark patterns.

    Science.gov (United States)

    Murmann, Denise C; Brumit, Paula C; Schrader, Bruce A; Senn, David R

    2006-07-01

    The purpose of this study was to compare the jaw shapes and bite mark patterns of wild and domestic animals to assist investigators in their analysis of animal bite marks. The analyses were made on 12 species in the Order Carnivora housed in the Mammalian Collection at the Field Museum of Natural History in Chicago, Illinois. In addition to metric analysis, one skull from each species was photographed as a representative sample with an ABFO No. 2 scale in place. Bite patterns of the maxillary and mandibular dentition were documented using foamed polystyrene exemplars, which were also photographed. A total of 486 specimens were examined to analyze the jaw and bite mark patterns. A modified technique for measuring intercanine distances was developed to more accurately reflect the characteristics seen in animal bite marks. In it, three separate areas were measured on the canines, rather than just the cusp tip. This was to maximize the amount of information acquired from each skull, specifically to accommodate variances in the depth of bite injuries.

  19. 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.

  20. Development of Low-Cost Remote-Control Generators Based on BiTe Thermoelectric Modules

    Science.gov (United States)

    Juanicó, Luis E.; Rinalde, Fabián; Taglialavore, Eduardo; Molina, Marcelo

    2013-07-01

    This paper presents a new thermogenerator based on moderate-temperature (up to 175°C) BiTe modules available on the open market. Despite this handicap relative to commercial thermogenerators based on high-temperature proprietary-technology PbBi modules (up to 560°C), this new design may become economically competitive due to its innovative thermal sink. Our thermal sink is based on a free-convection water loop built with standard tubing and household hot-water radiators, leading to a more practical, modular design. So, the specific cost of about 55,000 USD/kW obtained for this 120-W prototype is improved to 33,000 USD/kW for a 1-kW unit, which represents about half the price of commercial thermogenerators. Moreover, considering recently launched BiTe modules (that withstand up to 320°C), our proposition could have an even more favorable outlook.

  1. Adder bite: an uncommon cause of compartment syndrome in northern hemisphere

    Directory of Open Access Journals (Sweden)

    Evers Lars H

    2010-09-01

    Full Text Available Abstract Snakebite envenomation is an uncommon condition in the northern hemisphere, but requires high vigilance with regard to both the systemic effects of the venom and the locoregional impact on the soft tissues. Bites from the adder, Vipera Berus, may have serious clinical consequences due to systemic effects. A case of a 44-year-old man is reported. The patient was bitten in the right hand. He developed fasciotomy-requiring compartment syndrome of the upper limb. Recognition of this most seldom complication of an adder bite is vital to save the limb. We recommend that the classical signs and symptoms of compartment syndrome serve as indication for surgical decompression.

  2. Studying the effects of Bite plane application in intruding and extruding the teeth in patients with deep bite

    Directory of Open Access Journals (Sweden)

    M. Shirazi

    1987-08-01

    Full Text Available Deep bite is a major clinical problem manifested as higher than normal overbite in anterior region of the jaws. Various studies were conducted to identify the effects of using bite plan and its results. 14 subjects with deep bite were selected out of 400 students of a school who had not proximal caries and had not lost any permanent teeth with healthy periodontal condition. 8 patients were considered as case group and the 6 other as the control group. In case group, a simple labial arc with acrylic palate that caused a gap in occlusion was placed. 2 lateral radiographs were obtained both pre and post 14 months treatment period. After cephalometric analysis, due to bite plane application significant intrusion in mandibular  incisors were observed as well as elongation in both maxillary and mandibular molars.

  3. The Effects of Drag and Tidal Forces on the Orbits of High-Velocity Clouds

    Science.gov (United States)

    Fernandes, Alexandre; Benjamin, R. A.

    2013-06-01

    Over the past several years, orbital constraints have been obtained for several high velocity cloud complexes surrounding the Milky Way: Complex GCP (Smith Cloud), Complex A, Complex H, Complex GCN, and the Magellanic Stream. We summarize what is known about the orbits of these clouds and and discuss how well each of these complexes fits a balistic trajectory, and discuss how the length of a complex across the sky is related to the inital "fragmentation" and velocity dispersion of the clouds. We then introduce gas drag into the simulation of the orbits of these complexes. We present analytical tests of our numerical method and characterize the departure of the clouds from the ballistic trajectory as a function of drag parameters (ambient gas density and velocity and cloud column density). Using the results of these simulations we comment on the survivability and ultimate fate of HVC in the context of the different models of drag forces.

  4. Trial of "Force and Motion Conceptual Evaluation" Tests in Japanese High Schools

    Science.gov (United States)

    Ryu, Junpei; Iwama, Toru; Yamazaki, Toshiaki; Ogawa, Masashi; Sakatani, Takafumi; Uchimura, Hiroshi; Taniguchi, Kazunari; Murata, Takatoshi

    A tentative version of Japanese translation of "Force and Motion Conceptual Evaluation" was used in a preliminary research to investigate high school students' conceptual understanding of Newtonian dynamics after the students attended formal courses on the topic in 2006-07. The results obtained were generally similar to those of post-tests after traditional lectures in universities in U.S.A.. It was also used as pre- and post-test at two extramural classes on dynamics based on the active learning materials. The results of those uses suggested a well validated version of the translated test and more systematic large scale research can contribute well to physics education research in Japan.

  5. High-speed atomic force microscopy reveals rotary catalysis of rotorless F₁-ATPase.

    Science.gov (United States)

    Uchihashi, Takayuki; Iino, Ryota; Ando, Toshio; Noji, Hiroyuki

    2011-08-05

    F(1) is an adenosine triphosphate (ATP)-driven motor in which three torque-generating β subunits in the α(3)β(3) stator ring sequentially undergo conformational changes upon ATP hydrolysis to rotate the central shaft γ unidirectionally. Although extensive experimental and theoretical work has been done, the structural basis of cooperative torque generation to realize the unidirectional rotation remains elusive. We used high-speed atomic force microscopy to show that the rotorless F(1) still "rotates"; in the isolated α(3)β(3) stator ring, the three β subunits cyclically propagate conformational states in the counterclockwise direction, similar to the rotary shaft rotation in F(1). The structural basis of unidirectionality is programmed in the stator ring. These findings have implications for cooperative interplay between subunits in other hexameric ATPases.

  6. 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.

  7. 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...

  8. 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.

  9. Risk factors for stereotypic behavior and self-biting in rhesus macaques (Macaca mulatta): animal's history, current environment, and personality.

    Science.gov (United States)

    Gottlieb, Daniel H; Capitanio, John P; McCowan, Brenda

    2013-10-01

    Captive rhesus macaques sometimes exhibit undesirable abnormal behaviors, such as motor stereotypic behavior (MSB) and self-abuse. Many risk factors for these behaviors have been identified but the list is far from comprehensive, and large individual differences in rate of behavior expression remain. The goal of the current study was to determine which experiences predict expression of MSB and self-biting, and if individual differences in personality can account for additional variation in MSB expression. A risk factor analysis was performed utilizing data from over 4,000 rhesus monkeys at the California National Primate Research Center. Data were analyzed using model selection, with the best fitting models evaluated using Akaike Information Criterion. Results confirmed previous research that males exhibit more MSB and self-biting than females, MSB decreases with age, and indoor reared animals exhibit more MSB and self-biting than outdoor reared animals. Additionally, results indicated that animals exhibited less MSB and self-biting for each year spent outdoors; frequency of room moves and number of projects positively predicted MSB; pair separations positively predicted MSB and self-biting; pair housed animals expressed less MSB than single housed and grate paired animals; and that animals expressed more MSB and self-biting when in bottom rack cages, or cages near the room entrance. Based on these results we recommend limiting exposure to these risk factors when possible. Our results also demonstrated a relationship between personality and MSB expression, with animals low on gentle temperament, active in response to a human intruder, and high on novel object contact expressing more MSB. From these results we propose that an animal's MSB is related to its predisposition for an active personality, with active animals expressing higher rates of MSB.

  10. Recombination and selectional forces in cyanopeptolin NRPS operons from highly similar, but geographically remote Planktothrix strains

    Directory of Open Access Journals (Sweden)

    Kristensen Tom

    2008-08-01

    Full Text Available Abstract Background Cyanopeptolins are nonribosomally produced heptapetides showing a highly variable composition. The cyanopeptolin synthetase operon has previously been investigated in three strains from the genera Microcystis, Planktothrix and Anabaena. Cyanopeptolins are displaying protease inhibitor activity, but the biological function(s is (are unknown. Cyanopeptolin gene cluster variability and biological functions of the peptide variants are likely to be interconnected. Results We have investigated two cyanopeptolin gene clusters from highly similar, but geographically remote strains of the same genus. Sequencing of a nonribosomal peptide synthetase (NRPS cyanopeptolin gene cluster from the Japanese strain Planktothrix NIES 205 (205-oci, showed the 30 kb gene cluster to be highly similar to the oci gene cluster previously described in Planktothrix NIVA CYA 116, isolated in Norway. Both operons contained seven NRPS modules, a sulfotransferase (S and a glyceric acid loading (GA-domain. Sequence analyses showed a high degree of conservation, except for the presence of an epimerase domain in NIES 205 and the regions around the epimerase, showing high substitution rates and Ka/Ks values above 1. The two strains produce almost identical cyanopeptolins, cyanopeptolin-1138 and oscillapeptin E respectively, but with slight differences regarding the production of minor cyanopeptolin variants. These variants may be the result of relaxed adenylation (A-domain specificity in the nonribosomal enzyme complex. Other genetic markers (16S rRNA, ntcA and the phycocyanin cpcBA spacer were identical, supporting that these geographically separated Planktothrix strains are closely related. Conclusion A horizontal gene transfer event resulting in exchange of a whole module-encoding region was observed. Nucleotide statistics indicate that both purifying selection and positive selection forces are operating on the gene cluster. The positive selection forces are

  11. Measurement of repulsive force of high Tc materials due to Meissner effect and its two dimensional distribution

    Science.gov (United States)

    Ishigaki, H.; Itoh, M.; Hida, A.; Endo, H.; Oya, T.

    1991-03-01

    As a basic study for magnetic bearings using high-Tc superconductors, evaluations of the materials were conducted. These evaluations included measurements of the repulsive force and lateral restoring force of various kinds of YBCO pellets. Pure air, which was supplied in the process of fabrication, and the presence of Ag in YBCO showed evidence of the effects of increasing the repulsive force. The lateral restoring force which was observed in the lateral displacement of a levitated permanent magnet over YBCO pellets was also affected by pure air and the presence of Ag. A new measuring instrument for magnetic fields was developed by using a highly sensitive force sensor. Because this instrument has the capability of measuring the repulsive force due to the Meissner effect, it was used for evaluating the two-dimensional distribution of superconducting properties. Results show that the pellets had nonuniform superconducting properties. The two-dimensional distribution of residual flux density on the pellets which had been cooled in a magnetic field (field cooling) was also observed by means of the instrument. The mechanism for generating lateral force is discussed in relation to the distribution.

  12. An urban Northeastern United States alligator bite.

    Science.gov (United States)

    Shepherd, Suzanne Moore; Shoff, William H

    2014-05-01

    Individuals who live and work in the Southeastern coastal range of the 3 US crocodilian carnivores, American alligators, American crocodiles, and caiman, understand the risks of reptile-human encounters. Individuals who live in other parts of the country maybe exposed through contact with exotic pets at private homes, small menageries, or petting zoos or from escaped or abandoned animals. During these encounters, individuals may be severely injured.Emergency medical services, law enforcement, and animal welfare workers in nonhabitat areas are usually not trained in the handling and safe removal of injured individuals from the scene when the reptile is present. The emergency management of large crocodilian injuries is similar to that of other major trauma; however, providers also must take into consideration the significant crush component potentially inflicted by the tremendous bite power and shaking inflicting during attacks by these large reptiles, appropriate antibiotic coverage for less common organisms that inhabit their mouths, and management of possible psychological distress, including posttraumatic stress disorder produced by such an unusual attack. Emergency physicians should support the development of a readily available national database of scientifically collect information on attacks to inform appropriate care and support efforts to explore responsible measures that the USDA Animal and Plant Health Inspection Service and other appropriate local, state, and federal agencies can take to ensure ethical and biologically sustainable management of our large reptiles, which also helps to ensure the safety of the public.

  13. A rare case of multiple rattlesnake bites.

    Science.gov (United States)

    Iliev, Yanko T; Kristeva, Sasha A; Prancheva, Maria G

    2013-01-01

    The rattlesnake (Crotalus adamanteus) is a venomous viper inhabiting the southeastern parts of the United States. It is not found in the Balkans and Europe habitats. Subjects of the species are grown and seen in museums, exhibitions and terrariums, and sometimes in private collections. This may generate potentially toxic exposures to the venom in accidental contact. Acute poisoning with rattlesnake poison in Bulgaria is exotic, rare and even casuistic. The venom of the rattlesnake exhibits neuropathic, proteolytic and hemolytic activities. Antivenom is not currently easily available in Bulgaria--it is not usually stored in hospitals because it is very rarely used and therefore rather expensive. We present a case of multiple envenomation (two different occasions) of one and the same person who kept rattlesnakes in a private terrarium. Local toxic syndrome was observed with burning and stinging pain at bite site combined with limited hemorrhage and necrosis. The hemolytic reaction and the local toxic results were successfully managed without resorting to any specific antidotal therapy.

  14. The use of a wax bite wafer and a double computed tomography scan procedure to obtain a three-dimensional augmented virtual skull model.

    Science.gov (United States)

    Swennen, Gwen R J; Mommaerts, Maurice Y; Abeloos, Johan; De Clercq, Calix; Lamoral, Philippe; Neyt, Nathalie; Casselman, Jan; Schutyser, Filip

    2007-05-01

    A detailed visualization of the interocclusal relationship is essential in a three-dimensional virtual planning setup for orthognathic and facial orthomorphic surgery. The purpose of this study was to introduce and evaluate the use of a wax bite wafer in combination with a double computed tomography (CT) scan procedure to augment the three-dimensional virtual model of the skull with a detailed dental surface. A total of 10 orthognathic patients were scanned after a standardized multislice CT scanning protocol with dose reduction with their wax bite wafer in place. Afterward, the impressions of the upper and lower arches and the wax bite wafer were scanned for each patient separately using a high-resolution standardized multislice CT scanning protocol. Accurate fitting of the virtual impressions on the wax bite wafer was done with surface matching using iterative closest points. Consecutively, automatic rigid point-based registration of the wax bite wafer on the patient scan was performed to implement the digital virtual dental arches into the patient's skull model (Maxilim, version 2.0; Medicim NV, St-Niklaas, Belgium). Probability error histograms showed errors of wax bite wafer with the double CT scan procedure allowed for the setup of an accurate three-dimensional virtual augmented model of the skull with detailed dental surface. However, from a clinical workload, data handling, and computational point of view, this method is too time-consuming to be introduced in the clinical routine.

  15. High-density force myography: A possible alternative for upper-limb prosthetic control

    Directory of Open Access Journals (Sweden)

    Ashkan Radmand, PhD

    2016-07-01

    Full Text Available Several multiple degree-of-freedom upper-limb prostheses that have the promise of highly dexterous control have recently been developed. Inadequate controllability, however, has limited adoption of these devices. Introducing more robust control methods will likely result in higher acceptance rates. This work investigates the suitability of using high-density force myography (HD-FMG for prosthetic control. HD-FMG uses a high-density array of pressure sensors to detect changes in the pressure patterns between the residual limb and socket caused by the contraction of the forearm muscles. In this work, HD-FMG outperforms the standard electromyography (EMG-based system in detecting different wrist and hand gestures. With the arm in a fixed, static position, eight hand and wrist motions were classified with 0.33% error using the HD-FMG technique. Comparatively, classification errors in the range of 2.2%–11.3% have been reported in the literature for multichannel EMG-based approaches. As with EMG, position variation in HD-FMG can introduce classification error, but incorporating position variation into the training protocol reduces this effect. Channel reduction was also applied to the HD-FMG technique to decrease the dimensionality of the problem as well as the size of the sensorized area. We found that with informed, symmetric channel reduction, classification error could be decreased to 0.02%.

  16. 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.

  17. 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.

  18. A miniaturized, high frequency mechanical scanner for high speed atomic force microscope using suspension on dynamically determined points.

    Science.gov (United States)

    Herfst, Rodolf; Dekker, Bert; Witvoet, Gert; Crowcombe, Will; de Lange, Dorus; Sadeghian, Hamed

    2015-11-01

    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.

  19. Gold-decorated highly ordered self-organized grating-like nanostructures on Ge surface: Kelvin probe force microscopy and conductive atomic force microscopy studies

    Science.gov (United States)

    Alam Mollick, Safiul; Kumar, Mohit; Singh, Ranveer; Satpati, Biswarup; Ghose, Debabrata; Som, Tapobrata

    2016-10-01

    Nanoarchitecture by atomic manipulation is considered to be one of the emerging trends in advanced functional materials. It has a gamut of applications to offer in nanoelectronics, chemical sensing, and nanobiological science. In particular, highly ordered one-dimensional semiconductor nanostructures fabricated by self-organization methods are in high demand for their high aspect ratios and large number of applications. An efficient way of fabricating semiconductor nanostructures is by molecular beam epitaxy, where atoms are added to a crystalline surface at an elevated temperature during growth, yielding the desired structures in a self-assembled manner. In this article, we offer a room temperature process, in which atoms are sputtered away by ion impacts. Using gold ion implantation, the present study reports on the formation of highly ordered self-organized long grating-like nanostructures, with grooves between them, on a germanium surface. The ridges of the patterns are shown to have flower-like protruding nanostructures, which are mostly decorated by gold atoms. By employing local probe microscopic techniques like Kelvin probe force microscopy and conductive atomic force microscopy, we observe a spatial variation in the work function and different nanoscale electrical conductivity on the ridges of the patterns and the grooves between them, which can be attributed to gold atom decorated ridges. Thus, the architecture presented offers the advantage of using the patterned germanium substrates as periodic arrays of conducting ridges and poorly conducting grooves between them.

  20. Task III: Development of an Effective Computational Methodology for Body Force Representation of High-speed Rotor 37

    Science.gov (United States)

    Tan, Choon-Sooi; Suder, Kenneth (Technical Monitor)

    2003-01-01

    A framework for an effective computational methodology for characterizing the stability and the impact of distortion in high-speed multi-stage compressor is being developed. The methodology consists of using a few isolated-blade row Navier-Stokes solutions for each blade row to construct a body force database. The purpose of the body force database is to replace each blade row in a multi-stage compressor by a body force distribution to produce same pressure rise and flow turning. To do this, each body force database is generated in such a way that it can respond to the changes in local flow conditions. Once the database is generated, no hrther Navier-Stokes computations are necessary. The process is repeated for every blade row in the multi-stage compressor. The body forces are then embedded as source terms in an Euler solver. The method is developed to have the capability to compute the performance in a flow that has radial as well as circumferential non-uniformity with a length scale larger than a blade pitch; thus it can potentially be used to characterize the stability of a compressor under design. It is these two latter features as well as the accompanying procedure to obtain the body force representation that distinguish the present methodology from the streamline curvature method. The overall computational procedures have been developed. A dimensional analysis was carried out to determine the local flow conditions for parameterizing the magnitudes of the local body force representation of blade rows. An Euler solver was modified to embed the body forces as source terms. The results from the dimensional analysis show that the body forces can be parameterized in terms of the two relative flow angles, the relative Mach number, and the Reynolds number. For flow in a high-speed transonic blade row, they can be parameterized in terms of the local relative Mach number alone.

  1. Acute interstitial nephritis in patients with viperine snake bite: Single center experience of a rare presentation

    Directory of Open Access Journals (Sweden)

    Vishal Golay

    2012-01-01

    Full Text Available Acute renal failure following vasculotoxic viperine snake bites is very common in South Asia. Acute tubular necrosis and acute cortical necrosis are the common findings, with acute interstitial nephritis (AIN being a rare presentation. We conducted renal biopsies in all patients who were admitted in our institute with viperine snake bite-related acute kidney injury (AKI and who did not improve after three weeks of supportive care. Patients who had findings of AIN on renal histology were included for this study. Of a total of 42 patients, there were five patients (11.9% with AIN. Our series of five patients is the largest series of this rare presentation in the literature. All of these five patients had features of severe envenomation, severe AKI network stage of AKI and very high antivenom requirements. They had a very prolonged stay in the hospital, and four of the five patients developed chronic kidney disease on follow-up. The overall outcome in this group was worse as compared with those who did not have AIN. AIN following viperine snake bites is not a very rare presentation. The reason for the development of this pathology is unclear, but direct venom-related effects are possible. This presentation portends a poor overall long-term prognosis as demonstrated in our case series.

  2. Particle Transportation Through the JLab Hall A BigBite Spectrometer

    Science.gov (United States)

    Alsalmi, Sheren

    2015-04-01

    The BigBite spectrometer of the Hall A Facility of Jefferson Lab is under refurbishment for use in an experiment (E120-10-103) to measure deep inelastic electron scattering off helium-3 and tritium mirror nuclei in the valence quark region (high Bjorken x range). The experiment will use an 11 GeV upgraded beam to determine the ratio of the neutron to proton F2 inelastic structure functions, and the ratio of the down to up quark, d/u, quark probability distributions in the nucleon. The BigBite spectrometer is based on a custom-shaped dipole magnet, which provides for large momentum and angular acceptances needed for the above measurements. Simulations using a ROOT-based Monte Carlo model for tracking and visualizing scattered electrons passing through the BigBite magnet will be presented. The optics parameters of the dipole magnet have been extracted from a field map produced by a TOSCA magnetostatics calculation. The simulations are necessary to estimate the phase space of the scattered electrons inside the relocated detectors of the spectrometer, and check for electrons which could possibly miss a detector and escape detection. This work is supported by Saudi Arabian Cultural Mission SACM, Kent State University, NSF Grant PHY-1405814, and DOE Contract DE-AC05-06OR23177. Kent State University, Kent, OH, 44242.

  3. High-multipolar effects on the Casimir force: the non-retarded limit

    CERN Document Server

    Noguez, C; Esquivel-Sirvent, R; Villarreal, C; Noguez, Cecilia; Roman-Velazquez, Carlos E.; Esquivel-Sirvent, Raul; Villarreal, Carlos

    2003-01-01

    We calculate exactly the Casimir force or dispersive force, in the non-retarded limit, between a spherical nanoparticle and a substrate beyond the London's or dipolar approximation. We find that the force is a non-monotonic function of the distance between the sphere and the substrate, such that, it is enhanced by several orders of magnitude as the sphere approaches the substrate. Our results do not agree with previous predictions like the Proximity theorem approach.

  4. The performance of bonded magnets used in the treatment of anterior open bite.

    Science.gov (United States)

    Noar, J H; Shell, N; Hunt, N P

    1996-05-01

    This investigation examined the magnetic flux and repulsive force of neodymium-iron-boron (Nd-Fe-B) magnets based on Nd2Fe14B with acrylic coatings in different orientations. The flux was measured with a Hall probe and the force measured by electronic scales with the magnets mounted on a laboratory jack. Results show that there were no magnetic losses after embedding the magnets in acrylic bite-blocks, although there were significant flux losses when the magnet blocks were directly heated. The alignment of the magnets over each other was of the utmost importance and significantly affected the repulsive force between the magnets. When the magnets were mounted in an articulator to simulate jaw movement, the force levels between the magnets was further reduced as a result of the effects of the rotation of the articulator. It is concluded that Nd-Fe-B type magnets embedded in acrylic can be used to give predictable repulsive forces in the mouth. The dramatic reduction in force levels when the magnets are not in optimal alignment, however, makes their effectiveness in aiding intrusion of teeth doubtful.

  5. Control Parametric Analysis on Improving Park Restoring Force Model and Damage Evaluation of High-Strength Structure

    Directory of Open Access Journals (Sweden)

    Huang-bin Lin

    2016-01-01

    Full Text Available In the dynamic time-history analysis of structural elastoplasticity, it is important to develop a universal mathematical model that can describe the force-displacement characteristics for restoring force. By defining three control parameters (stiffness degradation, slip closure γ, energy degradation β, the Park restoring force mathematical model can simulate various components. In this study, the Park restoring force has been improved by adding two control parameters (energy-based strength degradation βe and ductility-based strength degradation βd. Based on the testing data, the constitutive model is input and 55 numerical models are developed to analyze the effects of various parameters on structural behavior. Conclusion. (1 β has determinative effect on structural behavior; the effect of βe is basically consistent with that of β; α has significant effect on shear forces and bending moments; γ has significant effect on displacements and accelerations; βd has significant effect on shearing forces, acceleration, and total energy consumptions. (2 Based on the classification of four types of damage level, the recommended values for α, γ, β, βe, and βd are presented. (3 Based on the testing data of high-strength columns, the recommended values for the five control parameters of the improved Park restoring force model are presented.

  6. High-speed atomic force microscopy for large scan sizes using small cantilevers

    Science.gov (United States)

    Braunsmann, Christoph; Schäffer, Tilman E.

    2010-06-01

    We present a high-speed atomic force microscope that exhibits a number of practical advantages over previous designs. Its central component is a high-speed scanner with a maximum scan size of 23 µm × 23 µm and a conveniently large sample stage area (6.5 mm × 6.5 mm). In combination with small cantilevers, image rates of up to 46 images s - 1 in air and 13 images s - 1 in liquid are reached under z-feedback control. By large scan size imaging of collagen fibrils in air, sample velocities of 8.8 mm s - 1 in the xy-direction and 11 mm s - 1 in the z-direction are reached. To provide optimized imaging conditions for both large and small scan sizes, a modular scanner design allows easily exchanging the x- and y-piezos. The scanner is therefore also suited for investigations on the molecular and atomic scale, which is demonstrated by imaging the step dynamics of a calcite surface during dissolution and the hexagonal lattice of a mica surface in liquid.

  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. High-speed atomic force microscopy reveals structural dynamics of amyloid β1-42 aggregates.

    Science.gov (United States)

    Watanabe-Nakayama, Takahiro; Ono, Kenjiro; Itami, Masahiro; Takahashi, Ryoichi; Teplow, David B; Yamada, Masahito

    2016-05-24

    Aggregation of amyloidogenic proteins into insoluble amyloid fibrils is implicated in various neurodegenerative diseases. This process involves protein assembly into oligomeric intermediates and fibrils with highly polymorphic molecular structures. These structural differences may be responsible for different disease presentations. For this reason, elucidation of the structural features and assembly kinetics of amyloidogenic proteins has been an area of intense study. We report here the results of high-speed atomic force microscopy (HS-AFM) studies of fibril formation and elongation by the 42-residue form of the amyloid β-protein (Aβ1-42), a key pathogenetic agent of Alzheimer's disease. Our data demonstrate two different growth modes of Aβ1-42, one producing straight fibrils and the other producing spiral fibrils. Each mode depends on initial fibril nucleus structure, but switching from one growth mode to another was occasionally observed, suggesting that fibril end structure fluctuated between the two growth modes. This switching phenomenon was affected by buffer salt composition. Our findings indicate that polymorphism in fibril structure can occur after fibril nucleation and is affected by relatively modest changes in environmental conditions.

  9. Cantilevered bimorph-based scanner for high speed atomic force microscopy with large scanning range.

    Science.gov (United States)

    Zhou, Yusheng; Shang, Guangyi; Cai, Wei; Yao, Jun-en

    2010-05-01

    A cantilevered bimorph-based resonance-mode scanner for high speed atomic force microscope (AFM) imaging is presented. The free end of the bimorph is used for mounting a sample stage and the other one of that is fixed on the top of a conventional single tube scanner. High speed scanning is realized with the bimorph-based scanner vibrating at resonant frequency driven by a sine wave voltage applied to one piezolayer of the bimorph, while slow scanning is performed by the tube scanner. The other piezolayer provides information on vibration amplitude and phase of the bimorph itself simultaneously, which is used for real-time data processing and image calibration. By adjusting the free length of the bimorph, the line scan rate can be preset ranging from several hundred hertz to several kilohertz, which would be beneficial for the observation of samples with different properties. Combined with a home-made AFM system and a commercially available data acquisition card, AFM images of various samples have been obtained, and as an example, images of the silicon grating taken at a line rate of 1.5 kHz with the scan size of 20 microm are given. By manually moving the sample of polished Al foil surface while scanning, the capability of dynamic imaging is demonstrated.

  10. High-speed Lissajous-scan atomic force microscopy: scan pattern planning and control design issues.

    Science.gov (United States)

    Bazaei, A; Yong, Yuen K; Moheimani, S O Reza

    2012-06-01

    Tracking of triangular or sawtooth waveforms is a major difficulty for achieving high-speed operation in many scanning applications such as scanning probe microscopy. Such non-smooth waveforms contain high order harmonics of the scan frequency that can excite mechanical resonant modes of the positioning system, limiting the scan range and bandwidth. Hence, fast raster scanning often leads to image distortion. This paper proposes analysis and design methodologies for a nonlinear and smooth closed curve, known as Lissajous pattern, which allows much faster operations compared to the ordinary scan patterns. A simple closed-form measure is formulated for the image resolution of the Lissajous pattern. This enables us to systematically determine the scan parameters. Using internal model controllers (IMC), this non-raster scan method is implemented on a commercial atomic force microscope driven by a low resonance frequency positioning stage. To reduce the tracking errors due to actuator nonlinearities, higher order harmonic oscillators are included in the IMC controllers. This results in significant improvement compared to the traditional IMC method. It is shown that the proposed IMC controller achieves much better tracking performances compared to integral controllers when the noise rejection performances is a concern.

  11. Acoustic radiation force impulse (ARFI) imaging of zebrafish embryo by high-frequency coded excitation sequence.

    Science.gov (United States)

    Park, Jinhyoung; Lee, Jungwoo; Lau, Sien Ting; Lee, Changyang; Huang, Ying; Lien, Ching-Ling; Kirk Shung, K

    2012-04-01

    Acoustic radiation force impulse (ARFI) imaging has been developed as a non-invasive method for quantitative illustration of tissue stiffness or displacement. Conventional ARFI imaging (2-10 MHz) has been implemented in commercial scanners for illustrating elastic properties of several organs. The image resolution, however, is too coarse to study mechanical properties of micro-sized objects such as cells. This article thus presents a high-frequency coded excitation ARFI technique, with the ultimate goal of displaying elastic characteristics of cellular structures. Tissue mimicking phantoms and zebrafish embryos are imaged with a 100-MHz lithium niobate (LiNbO₃) transducer, by cross-correlating tracked RF echoes with the reference. The phantom results show that the contrast of ARFI image (14 dB) with coded excitation is better than that of the conventional ARFI image (9 dB). The depths of penetration are 2.6 and 2.2 mm, respectively. The stiffness data of the zebrafish demonstrate that the envelope is harder than the embryo region. The temporal displacement change at the embryo and the chorion is as large as 36 and 3.6 μm. Consequently, this high-frequency ARFI approach may serve as a remote palpation imaging tool that reveals viscoelastic properties of small biological samples.

  12. 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.

  13. 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

  14. 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

  15. Our Clinical Experiences in Snake Bites

    Directory of Open Access Journals (Sweden)

    Demet Altun

    2016-12-01

    Full Text Available In this study, we evaluate 25 cases who were admitted to the emergency service and transferred to the intensive care unit subsequently due to snakebite, prospectively. Clinical courses, toxic effects, complications and treatment approaches were aimed to be presented. Among the patients, 16 were female and 9 were male; the mean age was 42.1 (17-74 years. It was determined that all the cases were admitted to the hospital during working in the field in Eastern Anatolia Region, between the months of May and June, and between the hours of 15:00 to 18:00. When the cases were considered in terms of bitten body part, 15 were bitten from upper extremity and 10 were bitten from lower extremity. Within an hour the patients were admitted to a health facility with the complaints of nausea, pain, numbness, swelling and redness, and patients were transferred to emergency unit approximately within 1 hour (0.5 to 2 hours following the first intervention. Tetanus immunization is administered in all cases as the first intervention. Antivenom was administered to the 9 (36% of the patients in whom steroid, antihistamine and prophylactic antibiotic therapy was given in the intensive care unit. Under the control of infection clinic, antibiotic therapy was initiated to 13 (52% patients in who cellulitis, abscess, lymphedema and compartment syndrome were developed. Healing was observed approximately within 4 days (2-6 days and recovery was observed in all the cases. Patients admitted due to snake bites should be followed closely for at least 6 to 8 hours. According to the patient’s clinical condition and laboratory test results, early intervention therapy should be regulated and antivenom therapy should be administered in the presence of systemic symptoms.

  16. Assessment of open and incomplete bite correction by incisor overlap and optical density of polyvinyl siloxane bite registration.

    Science.gov (United States)

    Shpack, Nir; Einy, Shmuel; Beni, Lea; Vardimon, Alexander D

    2006-04-01

    Open bite (OB) is a generalized term, which could incorporate subgroups that react differently to vertical correction. The objectives of the present study were to detect vertical treatment changes in incomplete bite (IB: inter-incisor overlap with no lower incisor contact with teeth or palate) and OB (no inter-incisor overlap) groups compared with a complete bite (CB: inter-incisor overlap with full lower incisor contact with teeth or palate) control group, to evaluate treatment response of the central and lateral incisors, and to study the vertico-sagittal interaction. Dental casts were taken at three time points, pre-treatment, post-treatment, and after one year of retention, from 54 Class II patients (22 males and 32 females with a mean age of 11 years 6 months) divided into three groups: CB (n = 21), IB (n = 18) and OB (n = 15). Measurements included incisor overlap (mm) and optical density (OD/mm2) of occlusal bite registration made of polyvinl siloxane. Both CB and IB groups demonstrated post-retention bite opening. However, bite opening in the CB group was three times greater than that in the IB group (e.g. lower lateral = -1.42 mm, 118 OD/mm2 versus -0.40 mm, 107 OD/mm2). Conversely, the OB group showed a significant (P < 0.001) bite closure (e.g. lower lateral = 1.30 mm, -377 OD/mm2). Overjet changes affected OD measurements, causing diversity in OD and millimetric measurements of the lateral incisors in the IB group. In conclusion, the OB group demonstrated a significant stable vertical correction; a post-treatment non-contact inter-incisor relationship was determined by a vertico-sagittal relapse; and full compensation of an IB was not possible.

  17. Nuclear forces and the properties of matter at high temperature and density

    Energy Technology Data Exchange (ETDEWEB)

    Rayet, M.; Arnould, M.; Paulus, G.; Tondeur, F.

    1982-12-01

    We present two Skyrme-type forces which are particularly well suited for the description of presupernova core or matter in nascent neutron star. They are compared to other forces currently used in this field, with regard to finite nuclei and infinite matter properties, and to the coexistence of nuclei in a hot and dense nucleon gas.

  18. A method to calculate and counterbalance the inertia force of slider-crank mechanisms in high-speed presses

    Institute of Scientific and Technical Information of China (English)

    Jim Wang; Sheng-dun Zhao; Hu-shan Shi; Chun-jian Hua

    2009-01-01

    A new method to calculate and counterbalance the inertia force of slider-crank mechanisms in high-speed mechanical presses was put forward. By analyzing the kinematic characteristics of a center-located slider-crank mechanism whose crank rotates at a constant angular velocity, the kinematic parameters of the slide, connecting rod and crank were formulated approximately. On the basis of the results above, three inertia forces and the input moment in the mechanism during its idle running were investigated and formulated by dynamic analysis. A verification experiment was performed on a slider-crank mechanism at a high-speed press machine. The forces derived from the established formulas were compared respectively with those obtained by the ADAMS software and the classical method of connecting rod mass substitution. It was experimentally found that the proposed formulas have an improved performance over related earlier techniques. By use of these results, a 1000 kN 1250 rpm four-point high-speed press machine was designed and manufactured. The slide of this press is driven by four sets of slider-crank mechanisms with symmetrical layout and opposite rotation directions to counterbalance the horizontal inertia forces. Four eccentric counterbalance blocks were designed to counterbalance the vertical force after their mass and equivalent eccentric radius were formulated. The high-speed press machine designed by the proposed counterbalance method has worked with satisfactory performance and good dynamic balance for more than four years in practical production.

  19. The effect of temperature and menthol on carbonation bite.

    Science.gov (United States)

    Wise, Paul M; Bryant, Bruce

    2014-09-01

    Temperature and chemesthesis interact, but this interaction has not been fully examined for most irritants. The current experiments focus on oral pungency from carbonation. Previous work showed that cooling carbon dioxide (CO2) solutions to below tongue temperature enhanced rated bite. However, to the best of our knowledge, the effects of warming to above tongue temperature have not been examined. In Experiment 1, subjects sampled CO2 solutions at 4 nominal concentrations (0.0, 2.0, 2.8, and 4.0 v/v) × 5 temperatures (18.3, 24.5, 29.9, 34.5, and 39.6 (o)C). Subjects dipped their tongue tips into samples and rated bite. As in previous work, subjects rated cool solutions (25.0 (o)C and lower) as more intense. Warming solutions above tongue temperature (39.6 (o)C) did not affect ratings. Experiment 2 examined warmer temperatures (18.3, 33.9, 39.0, 44.9, and 48.2 ºC). Bite was enhanced only at 48.2 ºC, and a follow-up experiment suggested that enhancement was probably due to confusion between carbonation bite and mild heat pain. Experiment 3 examined the effect of menthol cooling by pretreating the tongue with menthol. Unlike physical cooling, menthol cooling had little or no effect on rated bite. The results are discussed in the context of candidate transduction mechanisms for carbonation sensation.

  20. Epidemiological aspects of snake bites on a Liberian rubber plantation.

    Science.gov (United States)

    Stahel, E

    1980-12-01

    During a one-year period 95 patients with a history of snake bite were admitted to the hospital of a Liberian rubber plantation. The population at risk included the field workers (tappers and slashers) with an incidence of 4.2 symptomatic snake bites per thousand per year. The incidence of symptomatic bites was 1.7 per thousand in the group of non-field employees and 0.4 per thousand per year in the group of non-employees. The temporary disability was between 3 and 5 days, and the loss of workings days due to snake bites was one day per 10,000 working days on the plantation. Among the 95 patients 27 did not show any symptoms of envenoming except occasional fang marks. 64 patients developed cytotoxic symptoms alone. In this group, the night adder (Causus maculatus) was the main responsible snake. 4 patients showed signs of systemic envenoming. Two were haematological and two were neurological in nature and caused by Bitis species and Naja species, respectively. No fatalities were noted. A definite maximum of snake bites was observed during October and November which corresponds to the transition from rainy to dry season.