4 research outputs found
Modulation of pain-induced endothelial dysfunction by hypnotisability
No full textMental stress induces endothelial dysfunction, that is a reduction of the post-occlusion brachial artery flow-mediated vasodilation (FMD). This does not occur in subjects highly susceptible to hypnosis (Highs) in either the waking or hypnotic state. The aim of the present experiment was to assess whether endothelial dysfunction is also induced by acute nociceptive stimulation and whether high hypnotisability and/or the specific instruction of analgesia prevent its occurrence in awake highly hypnotizable individuals. Thus, nine Highs and nine subjects with low susceptibility to hypnosis (Lows) underwent an experimental session including the administration of pressor pain and of pressor pain associated with the instruction of analgesia. Heart rate, basal artery diameters and brachial artery flow-mediated vasodilation were measured during stimulation and rest conditions. Heart rate exhibited slight changes not modulated by hypnotisability. During painful stimulation both Highs and Lows showed a decrease of FMD, but it was significantly less pronounced in Highs. During the administration of painful stimulation together with the instruction of analgesia, only Highs reported analgesia and their FMD no longer decreased. This study provides the first evidence of pain-related endothelial dysfunction and extends previous findings concerning a sort of natural protection of Highs against the vascular effects of mental stress to acute pain
Maxillofacial Trauma And Seat Belt: A 10-year Retrospective Study
No full textIntroduction: Brazil is among the countries with the highest prevalence of people injured by traffic accidents, showing that in 2008, levels reached 18. 3 victims for 100,000 habitants were victims of traffic accidents. Materials and methods: This retrospective study involved data collected from treated patients' charts at seven different hospitals located in three different cities all in the state of São Paulo, Brazil. Information was obtained through a standardized form, which was designed to investigate the epidemiologic features of maxillofacial traumas, restricted to victims of car accidents. Results: Three hundred ninety-six patients were victims of car crashes with mean age 29. 75 years. The age group 18-30 years showed an association with facial trauma in 96 patients, 41. 56 % of whom reported using seat belt. Le Fort I, II and III (70 %) and mandible (63. 11 %) were more associated with body traumas and seat belt use. The most common soft tissue lesion was laceration with 189 cases (42. 3 %). The treatment way was assessed, 93 (23 %) were treated surgically and 303 (77 %) underwent conservative treatment. Discussion: Classically, it is known front seat belt use was positively correlated with back seat belt use, healthy diet, dental and general health, regular walking, adequate sleep and no smoking. Accidents involving cars occurred more frequently in age group 18-30 years, suffering more general traumas and representing the nonusers group that wore fewer seat belts, caused, perhaps, by bigger access of the youth to cars, driving in high speed and to an inefficient fiscalization of the traffic laws. © 2012 Springer-Verlag.1712125(2010) Global status report on road safety: Time for action, , http://www.who.int/violence_injury_prevention/road_safety_status/2009/en/index.html, World Health Organization, Accessed 18 October 2010Haug, R.H., Foss, J., Maxillofacial injuries in the pediatric patient (2000) Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 90, pp. 126-134Wood, E.B., Freer, T.J., Incidence and aetiology of facial injuries resulting from motor vehicle accidents in Queensland for a three-year period (2000) Aust Dent J, 46, pp. 284-288Aksoy, E.A., Unlu, E., Sensoz, O., A retrospective study on epidemiology and treatment of maxillofacial fractures (2002) J Craniofacial Surg, 13, pp. 773-775Bachulis, L.B., Sangster, W., Gorrel, G.W., Long, W.B., Patterns of injury in helmeted and nonhelmeted motorcyclist (1988) Am J Surg, 155, pp. 196-197Yokoyama, T., Motozawa, Y., Sasaki, T., Hitosugi, M., A retrospective analysis of oral and maxillofacial injuries in motor vehicle accidents (2006) J Oral Maxillofacial Surg, 64, pp. 1731-1735Fonseca, A.S.F., Goldenberg, D., Alonso, N., Bastos, E., Stocchero, F.M.C., Seating position, seat belt wearing, and the consequences in facial fractures in car occupants (2007) Clinics, 62 (3), pp. 289-294Fasola, A.O., Lawoyin, J.O., Obiechina, A.E., Arotiba, J.T., Inner city maxillofacial fractures due to Road traffic accidents (2003) Dental Traumatology, 19, pp. 2-5Montovani, J.C., Campos, L.M.P., Gomes, M.A., Moraes, V.R.S., Ferreira, F.D., Nogueira, E.A., (2006) Rev Bras Otorrinolaringol, 72, pp. 235-241Lucht, U., A prospective study of accidental falls and resulting injuries in the home among elderly people (1971) Acta Sociomed Scand, 3 (2), pp. 105-120Lajunen, T., Simsekoglu, O., Relationship of seat belt use to health and driver behaviors (2009) Transport Res, 12, pp. 235-241Dimitroulis, G., Eyre, J., A 7-year review of maxillofacial trauma in a central London hospital (1991) Br Dental J, 170, pp. 300-302Camarini, E.T., Pavan, A.J., Iwaki, L.G., Barbosa, C.E.B., Estudo epidemiológico dos traumatismos bucomaxilofaciais na região metropolitana de Maringá-PR entre os anos de 1997 e 2003 (2004) Revista De Cirurgia E Traumatologia Buco-Maxilo-Facial, 4 (2), pp. 131-135Erol, B., Tanrikulu, R., Görgun, B., Maxillofacial fractures. Analysis of demographic distribuition and treatment in 2901 patients (25-year experience (2004) J Craniomaxillofac Surg, 32, pp. 308-313Buchanan, J., Colquhoun, A., Frieldlander, I., Evans, S., Whitley, B., Thomson, M., Maxillofacial fractures at Waikato Hospital, New Zealand:1989 to 2000 (2005) N Z Med, 118, pp. U159Lin, S., Levin, L., Goldman, S., Peled, M., Dentoalveolar and maxillofacial injuries-retrospective study from a level I trauma center in Israel (2007) Dent Traumamtology, 23, pp. 155-157Silva, A.C., Passeri, L.A., Mazzonetto, R., de Moraes, M., Moreira, R.W.F., Incidence of dental trauma associated with facial trauma in Brazil: a 1-year evaluation (2004) Dental Traumatol, 20, pp. 6-11Shahim, F.N., Cameron, P., McNeil, J.J., Maxillofacial trauma in major trauma patients (2006) Australian Dental Journal, 51 (3), pp. 225-230Al-Khateeh, T., Abdullab, F.M., Craniomaxillofacial injuries in the United Arab Emirates: a retrospective study (2007) J Oral Maxillofacial Surg, 65, pp. 1094-1101Sawazaki, R., Lima Jr., S.M., Asprino, L., Moreira, R.W.F., de Moraes, M., Incidence and patterns of mandibular condyle fractures (2010) J Oral Maxillofac Surg, 68, pp. 1252-1259Prince, J.D., Facial fractures and seat belts (1983) Br Dent J, 155, p. 12Simsekoglu, O., Lajunen, T., Relationship of seat belt use to health and driver behaviors (2009) Transport Res, 12, pp. 235-241Wood, C.D., Facial fractures and seat belts (1983) Br Dent J, 154, p. 353Boyle, J.M., Lampkin, C., (2008) 2007 Motor vehicle occupant safety survey-volume 2-seat belt report (report no. DOT-HS-810-975), , Washington, DC: U. S. Department of TransportationHogg, J.V., Stewart, T.C., Armstrong, J.E., Girotti, M.J., Epidemiology of maxillofacial injuries at trauma hospital in Ontario, Canadá, between 1992 and 1997 (2000) J Trauma, 49, pp. 425-432Mcmullin, B.T., Rhee, J.S., Pintar, F.A., Szabo, A., Yoganandan, N., Facial fractures in motor vehicle collisions (2009) Arch Facial Plast Surg, 11 (3), pp. 165-170Klenk, G., Kovacs, A., Etiology and patterns of facial fractures in the United Arab Emirates (2003) J Craniomaxillo Surgery, 14, pp. 79-84Ozgursoy, O.B., Mudermis, T., Yorulmaz, I., Kucuk, B., Demographic, epidemiologic, and surgical characteristics of maxillofacial fracture repair in a developing country (2009) Ear Nose Throat J, 88, pp. 20-24Gassner, R., Tuli, T., Hachl, O., Rudish, A., Ulmer, H., Crânio-maxillofacial trauma: a 10 year review of 9543 cases with 21067 injuries (2003) Journal Craniomaxillofacial Surg, 31, pp. 51-61Shenkar, C., Reddy, C.V.K., A five -year retrospective statistical analysis of maxillofacial injuries in patients admitted and treated t two hospitals of Mysore city (2008) Indian J Dent Res, 19 (4), pp. 304-30
Анализ влияния параметров операционного усилителя на характеристики конвертора отрицательного импеданса
No full textThe article deals with a low pass op-amp model with high gain at DC and a single-pole frequency response and presents a technique for simple analysis of negative inductance compensator (NIC) circuits. Analytical expressions are derived fo r NIC frequency response analysis in case of operational amplifier finite bandwidth. Besides, the ideal NIC circuit comparison results are provided. Calculations show that op-amp finite bandwidth has impact on NIC impedance at fre quencies 10 times lower than gain-bandwidth product. The obtained analytical results are in good agreement with experimental setup measurements of NIC implementation to electrically small antenna impedance matching.Рассмотрено использование операционного усилителя (ОУ) с характеристикой вида фильтра нижних частот, большим коэффициентом усиления по постоянному току и единственным полюсом в частотной характеристике в качестве компенсатора отрицательной индуктивности (КОИ) при подключении электрически малоразмерной штыревой антенны (ЭМША) к нагрузке. Предложена простая методика анализа цепей КОИ. Получены аналитические выражения для анализа параметров КОИ в зависимости от частоты в случае использования ОУ с конечной рабочей полосой частот и приведены результаты сравнения с идеальными цепями КОИ. Результаты показывают, что конечная полоса частот ОУ оказывает влияние на входной импеданс КОИ на частотах, в 10 раз меньших частоты единичного усиления ОУ. Полученные аналитические результаты хорошо согласуются с измерениями экспериментального макета, реализующего КОИ для согласования импеданса ЭМША
Предельные характеристики согласования приемных рамочных антенн с помощью нефостеровских цепей
No full textThe limiting characteristics of electrically small-sized loop antenna matching by means of non-Foster's negative inductance are studied. Various options for including negative inductance in frame antenna structure are considered. The analytical limit expression for the operating frequency band of the small-sized loop antenna with the inclusion of negative inductance in the gap of the conductor frame is obtained. It is shown that for practical implementation the most convenient is the scheme with the inclusion of negative inductance between the conducting plane and the free output of the frame. Such inclusion of negative inductance causes small loss in width of the working frequency band compared with the inclusion of this inductance in the gap of the frame conductive plane, but EMF induced in the frame is twice as large. An integral expression is obtained for the maximum band matching of the small-sized loop antenna with the inclusion of negative inductance in grounded output, the integral in which is calculated numerically for various small-sized loop antenna quality factor and ratios between resonant frequency of the frame and operating frequency range. The results obtained are similar to Fano-Yula restriction for passive matching chains
