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Sample records for diaphragm

  1. Materials for Slack Diaphragms

    Science.gov (United States)

    Puschmann, Traute

    1940-01-01

    This report deals with systematic experiments carried out on five diaphragm materials with different pretreatment, for the purpose of ascertaining the suitability of such materials for slack diaphragms. The relationship of deflection and load, temperature and moisture, was recorded. Of the explored materials, synthetic leather, balloon cloth, goldbeaters skin, Igelit and Buna, synthetic leather treated with castor oil is the most suitable material for the small pressure range required. Balloon cloth is nearly as good, while goldbeaters skin, Igelit and Buna were found to be below the required standards.

  2. Radial Field Piezoelectric Diaphragms

    Science.gov (United States)

    Bryant, R. G.; Effinger, R. T., IV; Copeland, B. M., Jr.

    2002-01-01

    A series of active piezoelectric diaphragms were fabricated and patterned with several geometrically defined Inter-Circulating Electrodes "ICE" and Interdigitated Ring Electrodes "ICE". When a voltage potential is applied to the electrodes, the result is a radially distributed electric field that mechanically strains the piezoceramic along the Z-axis (perpendicular to the applied electric field). Unlike other piezoelectric bender actuators, these Radial Field Diaphragms (RFDs) strain concentrically yet afford high displacements (several times that of the equivalent Unimorph) while maintaining a constant circumference. One of the more intriguing aspects is that the radial strain field reverses itself along the radius of the RFD while the tangential strain remains relatively constant. The result is a Z-deflection that has a conical profile. This paper covers the fabrication and characterization of the 5 cm. (2 in.) diaphragms as a function of poling field strength, ceramic thickness, electrode type and line spacing, as well as the surface topography, the resulting strain field and displacement as a function of applied voltage at low frequencies. The unique features of these RFDs include the ability to be clamped about their perimeter with little or no change in displacement, the environmentally insulated packaging, and a highly repeatable fabrication process that uses commodity materials.

  3. New Stethoscope With Extensible Diaphragm.

    Science.gov (United States)

    Takashina, Tsunekazu; Shimizu, Masashi; Muratake, Torakazu; Mayuzumi, Syuichi

    2016-08-25

    This study compared the diagnostic efficacy of the common suspended diaphragm stethoscope (SDS) with a new extensible diaphragm stethoscope (EDS) for low-frequency heart sounds. The EDS was developed by using an ethylene propylene diene monomer diaphragm. The results showed that the EDS enhanced both the volume and quality of low-frequency heart sounds, and improved the ability of examiners to auscultate such heart sounds. Based on the results of the sound analysis, the EDS is more efficient than the SDS. (Circ J 2016; 80: 2047-2049).

  4. Diaphragm Dysfunction in Critical Illness.

    Science.gov (United States)

    Supinski, Gerald S; Morris, Peter E; Dhar, Sanjay; Callahan, Leigh Ann

    2018-04-01

    The diaphragm is the major muscle of inspiration, and its function is critical for optimal respiration. Diaphragmatic failure has long been recognized as a major contributor to death in a variety of systemic neuromuscular disorders. More recently, it is increasingly apparent that diaphragm dysfunction is present in a high percentage of critically ill patients and is associated with increased morbidity and mortality. In these patients, diaphragm weakness is thought to develop from disuse secondary to ventilator-induced diaphragm inactivity and as a consequence of the effects of systemic inflammation, including sepsis. This form of critical illness-acquired diaphragm dysfunction impairs the ability of the respiratory pump to compensate for an increased respiratory workload due to lung injury and fluid overload, leading to sustained respiratory failure and death. This review examines the presentation, causes, consequences, diagnosis, and treatment of disorders that result in acquired diaphragm dysfunction during critical illness. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  5. Traumatic rupture of the diaphragm: CT findings

    International Nuclear Information System (INIS)

    Cho, Sung Tae; Kim, Sung Jin; Cha, Sang Hoon; Park, Kil Sun; Kim, Jin Hee; Yim, Se Hwan

    1995-01-01

    The aim of this study was to assess the clinical utility of the known CT signs of the traumatic rupture of the diaphragm. CT scans and chest radiographs were retrospectively reviewed in 13 patients who had diaphragmatic rupture confirmed by surgery. On chest radiographs the elevation of the diaphragm was evaluated. On CT, 1) discontinuity of the diaphragm, 2) lack of depiction of the diaphragm surrounding the herniated intraabdominal organs (absent diaphragm sign), and 3) fat seen lateral to the diaphragm (fat sign) were evaluated. Chest radiographs showed the elevation of the diaphragm in 11 patients (85%). CT scan showed absent diaphragm sign in 11 patients (85%), discontinuity of the diaphragm in 8 (62%), and fat sign in 7 (54%). All of 12 patients who had the left diaphragmatic rupture had one or more of the above findings. Discontinuity of the diaphragm, absent diaphragm sign, and fat sign may be helpful CT findings in the diagnosis of the traumatic rupture of the left diaphragm

  6. Fluid structure interaction in piston diaphragm pumps

    NARCIS (Netherlands)

    Van Rijswick, R.; Van Rhee, C.

    2013-01-01

    Piston diaphragm pumps are used world-wide for the transport of aggressive and/or abrasive fluids in the chemical, mining and mineral processing industries. Figure 1 shows a cross section of a piston diaphragm pump as is used in the mining and mineral processing industries for the transport of

  7. Fluid structure interaction in piston diaphragm pumps

    NARCIS (Netherlands)

    van Rijswick, R.J.A.

    2017-01-01

    Piston diaphragm pumps are used world-wide to transport abrasive and/or aggressive slurries against high discharge pressures in the mining, mineral processing and power industries. Limitation of excessive deformation of the diaphragm is of utmost importance for eliminating fatigue failures of the

  8. To detect anomalies in diaphragm walls

    NARCIS (Netherlands)

    Spruit, R.

    2015-01-01

    Diaphragm walls are potentially ideal retaining walls for deep excavations in densely built-up areas, as they cause no vibrations during their construction and provide structural elements with high strength and stiffness. In the recent past, however, several projects using diaphragm walls as soil

  9. Eventration of diaphragm with a rare association

    Directory of Open Access Journals (Sweden)

    Syed Shafiq

    2014-01-01

    Full Text Available Eventration of the diaphragm is a rare anomaly of unknown origin characterized by a permanent high position of one or rarely both the leaflets of the diaphragm, providing a potential space for the displacement of abdominal viscera on the affected side(s. The etiology, diagnosis, and management of this condition remains a controversial subject. We report a rare case of infiltrating squamous cell carcinoma of the esophagus in a patient with eventration of the diaphragm and gastric volvulus who presented to us with retrosternal discomfort. To the best of our knowledge, this rare association has not been reported in the literature, although one case of esophageal adenocarcinoma arising from Barrett′s esophagus in association with eventration of the diaphragm has been reported previously. This case again emphasis the varied associations of an eventration of the diaphragm.

  10. Radial-Electric-Field Piezoelectric Diaphragm Pumps

    Science.gov (United States)

    Bryant, Robert G.; Working, Dennis C.; Mossi, Karla; Castro, Nicholas D.; Mane, Pooma

    2009-01-01

    In a recently invented class of piezoelectric diaphragm pumps, the electrode patterns on the piezoelectric diaphragms are configured so that the electric fields in the diaphragms have symmetrical radial (along-the-surface) components in addition to through-the-thickness components. Previously, it was accepted in the piezoelectric-transducer art that in order to produce the out-of-plane bending displacement of a diaphragm needed for pumping, one must make the electric field asymmetrical through the thickness, typically by means of electrodes placed on only one side of the piezoelectric material. In the present invention, electrodes are placed on both sides and patterned so as to produce substantial radial as well as through-the-thickness components. Moreover, unlike in the prior art, the electric field can be symmetrical through the thickness. Tests have shown in a given diaphragm that an electrode configuration according to this invention produces more displacement than does a conventional one-sided electrode pattern. The invention admits of numerous variations characterized by various degrees of complexity. Figure 1 is a simplified depiction of a basic version. As in other piezoelectric diaphragm pumps of similar basic design, the prime mover is a piezoelectric diaphragm. Application of a suitable voltage to the electrodes on the diaphragm causes it to undergo out-of-plane bending. The bending displacement pushes a fluid out of, or pulls the fluid into, a chamber bounded partly by the diaphragm. Also as in other diaphragm pumps in general, check valves ensure that the fluid flows only in through one port and only out through another port.

  11. Diaphragms obtained by radiochemical grafting in PTFE

    International Nuclear Information System (INIS)

    Nenner, T.; Fahrasmane, A.

    1984-01-01

    Diaphragms for alkaline water electrolysis are prepared by radiochemical grafting of PTFE fabric with styrene, which is later on sulfonated, or with acrylic acid. The diaphragms obtained are mechanically resistant to potash at temperatures up to 200 0 C, but show some degrafting, which limits the lifetime. The sulfonated styrene group has been found to be more stable in electrolysis than the acrylic acid. In both cases, the incorporation of a cross-linking agent like divinyl benzene improves the lifetime of the diaphragms. Electrolysis during 500 hours at 120 0 C and 10 kAm 2 could be performed. (author)

  12. The Stress and Stiffness Analysis of Diaphragm

    Directory of Open Access Journals (Sweden)

    Qu Dongyue

    2017-01-01

    Full Text Available Diaphragm coupling with its simple structure, small size, high reliability, which can compensate for its input and output displacement deviation by its elastic deformation, is widely used in aerospace, marine, and chemical etc. This paper uses the ANSYS software and its APDL language to analysis the stress distribution when the diaphragm under the load of torque, axial deviation, centrifugal force, angular deviation and multiple loads. We find that the value of maximum stress usually appears in the outer or inner transition region and the axial deviation has a greater influence to the distribution of the stress. Based on above, we got three kinds of stiffness for axial, angular and torque, which the stiffness of diaphragm is nearly invariable. The results can be regard as an important reference for design and optimization of diaphragm coupling.

  13. Right Diaphragm Spontaneous Rupture: A Surgical Approach

    Directory of Open Access Journals (Sweden)

    Duilio Divisi

    2011-01-01

    Full Text Available We present a case of spontaneous rupture of the diaphragm, characterized by nonspecific symptoms. The rapid diagnosis and appropriate surgical approach led to a positive resolution of the pathology.

  14. Diaphragm adaptations in patients with COPD.

    NARCIS (Netherlands)

    Ottenheijm, C.A.C.; Heunks, L.M.A.; Dekhuijzen, P.N.R.

    2008-01-01

    Inspiratory muscle weakness in patients with COPD is of major clinical relevance. For instance, maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to hyperinflation-induced diaphragm

  15. Design of pressure-sensing diaphragm for MEMS capacitance diaphragm gauge considering size effect

    Science.gov (United States)

    Li, Gang; Li, Detian; Cheng, Yongjun; Sun, Wenjun; Han, Xiaodong; Wang, Chengxiang

    2018-03-01

    MEMS capacitance diaphragm gauge with a full range of (1˜1000) Pa is considered for its wide application prospect. The design of pressure-sensing diaphragm is the key to achieve balanced performance for this kind of gauges. The optimization process of the pressure-sensing diaphragm with island design of a capacitance diaphragm gauge based on MEMS technique has been reported in this work. For micro-components in micro scale range, mechanical properties are very different from that in the macro scale range, so the size effect should not be ignored. The modified strain gradient elasticity theory considering size effect has been applied to determine the bending rigidity of the pressure-sensing diaphragm, which is then used in the numerical model to calculate the deflection-pressure relation of the diaphragm. According to the deflection curves, capacitance variation can be determined by integrating over the radius of the diaphragm. At last, the design of the diaphragm has been optimized based on three parameters: sensitivity, linearity and ground capacitance. With this design, a full range of (1˜1000) Pa can be achieved, meanwhile, balanced sensitivity, resolution and linearity can be kept.

  16. Verification on reliability of diaphragm seal

    International Nuclear Information System (INIS)

    Ide, Hiroshi; Sakuta, Yoshiyuki; Hanawa, Yoshio; Tsuji, Tomoyuki; Tsuboi, Kazuaki; Nagao, Yoshiharu; Miyazawa, Masataka

    2009-06-01

    The main body of the JMTR is composed of reactor pressure vessel, core and reactor pool. At the bottom of the reactor pool, the Diaphragm-seal (2.6m outer diameter, 2m inner diameter, thickness 1.5mm) of the JMTR made of stainless steel is installed to prevent the water leak of the reactor pool and to absorb the expansion of the reactor pressure vessel due to pressure and temperature changes. In the long-term maintenance plans drawn up in 2004, it is required that the visual inspection for the diaphragm-seal should be carried out in 2007 and that the inspection should be carried out every around five-year. Therefore, prior to the refurbishment of the JMTR, the inspection device which is a deposition-collection apparatus with underwater-camera was developed, and the visual inspection was carried out to confirm the soundness of the diaphragm-seal. As a result, harmful flaws and/or corrosions were not inspected in the visual inspection, and the soundness of the diaphragm seal was confirmed. In future, the long-term integrity of the diaphragm-seal will could be achieved by conducting the periodic inspection. (author)

  17. Congenital duodenal diaphragm in eight children

    International Nuclear Information System (INIS)

    Nawaz, Akhtar; Matta, Hilal; Jacobsz, Alic; Al-Salem, Ahmad H.; Trad, Omar

    2004-01-01

    Congenital duodenal obstruction (CDO) is common and usually easy to diagnose cause of intestinal obstruction in the newborn, except when the cause of the obstruction is duodenal diaphragm. We describe our experience with eight children who had intrinsic duodenal obstruction secondary to a duodenal diaphragm. The medical record of 22 children with the diagnosis of congenital intrinsic duodenal were reviewed for age, sex, gestation, birth weight, clinical features, associated anomalies, method of diagnosis, treatment and outcome. Operative findings and procedures were obtained from the operative notes. Eight of 22 children (36.4%) had congenital duodenal diaphragm (CDD). In all children, the diagnosis was made from the plain abdominal X-ray, which showed the classic double-bubble appearence, and barium meal, which showed duodenal obstruction. Four patients had associated anomalies, including two with Down's syndrome intraoperatively, five patients were found to have duodenal diaphragm with a central hole, while the other three had complete duodenal diaphragms. Postoperatively, all patients did well. Six required total parenteral nutrition. The 100% survival rate among these children is comparable to that in Western countries, and can be attributed to the lack of major associated abnormalities, good perioperative management, and the availability of total parenteral nutrition. (author)

  18. Microfluidic Pumps Containing Teflon [Trademark] AF Diaphragms

    Science.gov (United States)

    Willis, Peter; White, Victor; Grunthaner, Frank; Ikeda, Mike; Mathies, Richard A.

    2009-01-01

    Microfluidic pumps and valves based on pneumatically actuated diaphragms made of Teflon AF polymers are being developed for incorporation into laboratory-on-a-chip devices that must perform well over temperature ranges wider than those of prior diaphragm-based microfluidic pumps and valves. Other potential applications include implanted biomedical microfluidic devices, wherein the biocompatability of Teflon AF polymers would be highly advantageous. These pumps and valves have been demonstrated to function stably after cycling through temperatures from -125 to 120 C. These pumps and valves are intended to be successors to similar prior pumps and valves containing diaphragms made of polydimethylsiloxane (PDMS) [commonly known as silicone rubber]. The PDMS-containing valves ae designed to function stably only within the temperature range from 5 to 80 C. Undesirably, PDMS membranes are somwehat porous and retain water. PDMS is especially unsuitable for use at temperatures below 0 C because the formation of ice crystals increases porosity and introduces microshear.

  19. MDCT diagnosis of penetrating diaphragm injury

    Energy Technology Data Exchange (ETDEWEB)

    Bodanapally, Uttam K.; Shanmuganathan, Kathirkamanathan; Mirvis, Stuart E.; Sliker, Clint W.; Fleiter, Thorsten R.; Sarada, Kamal; Miller, Lisa A. [University of Maryland School of Medicine, Department of Diagnostic Radiology, Baltimore, MD (United States); Stein, Deborah M. [University of Maryland, Department of Surgery, Shock Trauma Center, Baltimore, MD (United States); Alexander, Melvin [National Study Center for Trauma and Emergency Medical Systems, Baltimore, MD (United States)

    2009-08-15

    The purpose of the study was to determine the diagnostic sensitivity and specificity of multidetector CT (MDCT) in detection of diaphragmatic injury following penetrating trauma. Chest and abdominal CT examinations performed preoperatively in 136 patients after penetrating trauma to the torso with injury trajectory in close proximity to the diaphragm were reviewed by radiologists unaware of surgical findings. Signs associated with diaphragmatic injuries in penetrating trauma were noted. These signs were correlated with surgical diagnoses, and their sensitivity and specificity in assisting the diagnosis were calculated. CT confirmed diaphragmatic injury in 41 of 47 injuries (sensitivity, 87.2%), and an intact diaphragm in 71 of 98 patients (specificity, 72.4%). The overall accuracy of MDCT was 77%. The most accurate sign helping the diagnosis was contiguous injury on either side of the diaphragm in single-entry penetrating trauma (sensitivity, 88%; specificity, 82%). Thus MDCT has high sensitivity and good specificity in detecting penetrating diaphragmatic injuries. (orig.)

  20. MDCT diagnosis of penetrating diaphragm injury

    International Nuclear Information System (INIS)

    Bodanapally, Uttam K.; Shanmuganathan, Kathirkamanathan; Mirvis, Stuart E.; Sliker, Clint W.; Fleiter, Thorsten R.; Sarada, Kamal; Miller, Lisa A.; Stein, Deborah M.; Alexander, Melvin

    2009-01-01

    The purpose of the study was to determine the diagnostic sensitivity and specificity of multidetector CT (MDCT) in detection of diaphragmatic injury following penetrating trauma. Chest and abdominal CT examinations performed preoperatively in 136 patients after penetrating trauma to the torso with injury trajectory in close proximity to the diaphragm were reviewed by radiologists unaware of surgical findings. Signs associated with diaphragmatic injuries in penetrating trauma were noted. These signs were correlated with surgical diagnoses, and their sensitivity and specificity in assisting the diagnosis were calculated. CT confirmed diaphragmatic injury in 41 of 47 injuries (sensitivity, 87.2%), and an intact diaphragm in 71 of 98 patients (specificity, 72.4%). The overall accuracy of MDCT was 77%. The most accurate sign helping the diagnosis was contiguous injury on either side of the diaphragm in single-entry penetrating trauma (sensitivity, 88%; specificity, 82%). Thus MDCT has high sensitivity and good specificity in detecting penetrating diaphragmatic injuries. (orig.)

  1. Diaphragm walling for Sizewell B sets records

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The first phase of construction of the Sizewell-B nuclear reactor has been completed. This was the building of a diaphragm wall around the site. It is one of the largest and deepest diaphragm walls to be installed in Europe. The site can be pumped dry of groundwater and the foundations constructed in the dry. The specifications of the wall and its construction, using two Hydrofraise excavation rigs, are described. The excavated material is brought up as a slurry and the (bentonite) slurry is cleaned and desanded. Most of the wall has been formed using a plastic concrete but reinforced concrete has been used for some stretches. The diaphragm wall, which is 1258m long and 55m deep on average, was built in 19 weeks. (U.K.)

  2. Parametric study of roof diaphragm stiffness requirements

    International Nuclear Information System (INIS)

    Jones, W.D.; Tenbus, M.A.

    1991-01-01

    A common assumption made in performing a dynamic seismic analysis for a building is that the roof/floor system is open-quotes rigidclose quotes. This assumption would appear to be reasonable for many of the structures found in nuclear power plants, since many of these structures are constructed of heavily reinforced concrete having floor/roof slabs at least two feet in thickness, and meet the code requirements for structural detailing for seismic design. The roofs of many Department of Energy (DOE) buildings at the Oak Ridge Y-12 Plant in Oak Ridge, Tennessee, have roofs constructed of either metal, precast concrete or gypsum plank deck overlaid with rigid insulation, tar and gravel. In performing natural phenomena hazard assessments for one such facility, it was assumed that the existing roof performed first as a flexible diaphragm (zero stiffness) and then, rigid (infinitely stiff). For the flexible diaphragm model it was determined that the building began to experience significant damage around 0.09 g's. For the rigid diaphragm model it was determined that no significant damage was observed below 0.20 g's. A Conceptual Design Report has been prepared for upgrading/replacing the roof of this building. The question that needed to be answered here was, open-quotes How stiff should the new roof diaphragm be in order to satisfy the rigid diaphragm assumption and, yet, be cost effective?close quotes. This paper presents a parametric study of a very simple structural system to show that the design of roof diaphragms needs to consider both strength and stiffness (frequency) requirements. This paper shows how the stiffness of a roof system affects the seismically induced loads in the lateral, vertical load resisting elements of a building and provides guidance in determining how open-quotes rigidclose quotes a roof system should be in order to accomplish a cost effective design

  3. Free Piston Double Diaphragm Shock Tube

    OpenAIRE

    OGURA, Eiji; FUNABIKI, Katsushi; SATO, Shunichi; ABE, Takashi; 小倉, 栄二; 船曳, 勝之; 佐藤, 俊逸; 安部, 隆士

    1997-01-01

    A free piston double diaphragm shock tube was newly developed for generation of high Mach number shock wave. Its characteristics was investigated for various operation parameters; such as a strength of the diaphragm at the end of the comparession tube, an initial pressure of low pressure tube, an initial pressure of medium pressure tube and the volume of compression tube. Under the restriction of fixed pressures for the driver high pressure tube (32×10^5Pa) and the low pressure tube (40Pa) in...

  4. Treating traumatic injuries of the diaphragm

    Directory of Open Access Journals (Sweden)

    Dwivedi Sankalp

    2010-01-01

    Full Text Available Traumatic diaphragmatic injury (DI is a unique clinical entity that is usually occult and can easily be missed. Their delayed presentation can be due to the delayed rupture of the diaphragm or delayed detection of diaphragmatic rupture, making the accurate diagnosis of DI challenging to the trauma surgeons. An emergency laparotomy and thorough exploration followed by the repair of the defect is the gold standard for the management of these cases. We report a case of blunt DI in an elderly gentleman and present a comprehensive overview for the management of traumatic injuries of the diaphragm.

  5. Mathematical Modeling of Diaphragm Pneumatic Motors

    Directory of Open Access Journals (Sweden)

    Fojtášek Kamil

    2014-03-01

    Full Text Available Pneumatic diaphragm motors belong to the group of motors with elastic working parts. This part is usually made of rubber with a textile insert and it is deformed under the pressure of a compressed air or from the external mass load. This is resulting in a final working effect. In this type of motors are in contact two different elastic environments – the compressed air and the esaltic part. These motors are mainly the low-stroke and working with relatively large forces. This paper presents mathematical modeling static properties of diaphragm motors.

  6. Early development of the human pelvic diaphragm

    NARCIS (Netherlands)

    Koch, Wijnandus Franciscus Robertus Maria

    2006-01-01

    The last decade an increasing interest in the pelvic floor can be observed in medical sciences. The lack of data on the development of the human pelvic floor is striking. The early development of the human pelvic diaphragm was studied. Materials and methodsUse was made of 38 human embryos and

  7. The earliest history of diaphragm physiology.

    Science.gov (United States)

    Derenne, J P; Debru, A; Grassino, A E; Whitelaw, W A

    1994-12-01

    The diaphragm was recognized as a distinct anatomical structure in the earliest Greek writings. However, the precise description of wounds suffered by warriors during the Trojan war by Homer was not tied to any particular function. The diaphragm was assimilated to the region that harbours thought. The first physiologic explanations of respiration by Empedocles in the 5th century BC and the concepts introduced by Plato and Hippocrates did not include a significant participation of the diaphragm. Aristole was the first to link respiration to a particular organ and a specific movement of the thorax. However, he considered that it was the heart which caused the lungs to expand by heating them, and the lungs in turn forced the thorax to dilate, a concept which was to survive until the 17th century. As in Aristole's theory the diaphragm played no role in respiration and was just a fence separating the thorax from the abdomen. A major break through occurred in Alexandria in the 4th and 3rd century BC: Herophilus was the first to recognize that muscles were the agents of movement and Erasistratus performed animal experiments which showed that the respiratory muscles were the agents of respiratory movements, thus opening the way to the later discoveries of Galen.

  8. Diaphragm users should follow 13 tips for best effectiveness.

    Science.gov (United States)

    Reese, M; Hatcher, R A

    1984-11-01

    The following 13 tips should be presented by family planning practitioners to diaphragm users: 1) the client must be able to feel her cervix; 2) the diaphragm should be checked for tears or holes before each use; 3) it should always be used with contraceptive jelly or cream; 4) petroleum products should not be used with the diaphragm; 5) the device should be inserted in plentyof time before intercourse; 6) it should be used at every intercourse; 7) to insert the diaphragm, use 1 hand to hold the cup down and the dome up, fold the diaphragm in half, push it toward the back of the vagina, and tuck the front rim behind the pubic bone; 8) check placement of the diaphragm by ensuring that the soft rubber dome covers the cervix and the front rim is firmly behind the pubic bone; 9) be aware that the diaphragm is probably not in the correct position if it causes discomfort; 10) do not douche with the diaphragm in place; 11) leave the device in place for a least 6 hours after intercourse; 12) remove the diaphragm by hooking the index finger behind the front rim and pulling down and out, being careful not to puncture the diaphragm; and 13) wash the diaphragm with mild soap and water and store it in a platic container away from heat. If patients gain or lose more than 10 pounds, have a pregnancy or pelvic surgery, suspect that their diaphragm is too large or too small, or are experiencing discomfort or pain, they should have the fit checked. Finally, since several cases of toxic shock syndrome have occured in diaphragm users, patients should avoid leaving the diaphragm in place more than 24 hours and avoid its use during menstruation.

  9. Novel diaphragm for electrolytic cells. Final report

    International Nuclear Information System (INIS)

    The basic intent of these studies is to produce a diaphragm permeable to two types of ions, which have properties which are similar to those of asbestos. PTFE in the form of fabric is rendered hydrophilic by grafting monomer acrylic acid by a radio-chemical technique; two methods were utilized to do this: - Direct radio-chemical method under radiation - Pre-irradiation method in air under radiation and accelerated electronic radiation. The monomer acrylic acid was grafted in the presence or non-presence of cross-linking agents, the latter before developing a resistance derived from the diaphragms obtained at the agressivity of the medium in which they would be utilized

  10. Diaphragm Pump With Resonant Piezoelectric Drive

    Science.gov (United States)

    Izenson, Michael G.; Kline-Schoder, Robert J.; Shimko, Martin A.

    2007-01-01

    A diaphragm pump driven by a piezoelectric actuator is undergoing development. This pump is intended to be a prototype of lightweight, highly reliable pumps for circulating cooling liquids in protective garments and high-power electronic circuits, and perhaps for some medical applications. The pump would be highly reliable because it would contain no sliding seals or bearings that could wear, the only parts subject to wear would be two check valves, and the diaphragm and other flexing parts could be designed, by use of proven methods, for extremely long life. Because the pump would be capable of a large volumetric flow rate and would have only a small dead volume, its operation would not be disrupted by ingestion of gas, and it could be started reliably under all conditions. The prior art includes a number piezoelectrically actuated diaphragm pumps. Because of the smallness of the motions of piezoelectric actuators (typical maximum strains only about 0.001), the volumetric flow rates of those pumps are much too small for typical cooling applications. In the pump now undergoing development, mechanical resonance would be utilized to amplify the motion generated by the piezoelectric actuator and thereby multiply the volumetric flow rate. The prime mover in this pump would be a stack of piezoelectric ceramic actuators, one end of which would be connected to a spring that would be part of a spring-and-mass resonator structure. The mass part of the resonator structure would include the pump diaphragm (see Figure 1). Contraction of the spring would draw the diaphragm to the left, causing the volume of the fluid chamber to increase and thereby causing fluid to flow into the chamber. Subsequent expansion of the spring would push the diaphragm to the right, causing the volume of the fluid chamber to decrease, and thereby expelling fluid from the chamber. The fluid would enter and leave the chamber through check valves. The piezoelectric stack would be driven electrically to

  11. Ultrasonographic Assessment of Diaphragm Function in Critically Ill Subjects.

    Science.gov (United States)

    Umbrello, Michele; Formenti, Paolo

    2016-04-01

    The majority of patients admitted to the ICU require mechanical ventilation as a part of their process of care. However, mechanical ventilation itself or the underlying disease can lead to dysfunction of the diaphragm, a condition that may contribute to the failure of weaning from mechanical ventilation. However, extended time on the ventilator increases health-care costs and greatly increases patient morbidity and mortality. Nevertheless, symptoms and signs of muscle disease in a bedridden (or bed rest-only) ICU patient are often difficult to assess because of concomitant confounding factors. Conventional assessment of diaphragm function lacks specific, noninvasive, time-saving, and easily performed bedside tools or requires patient cooperation. Recently, the use of ultrasound has raised great interest as a simple, noninvasive method of quantification of diaphragm contractile activity. In this review, we discuss the physiology and the relevant pathophysiology of diaphragm function, and we summarize the recent findings concerning the evaluation of its (dys)function in critically ill patients, with a special focus on the role of ultrasounds. We describe how to assess diaphragm excursion and diaphragm thickening during breathing and the meaning of these measurements under spontaneous or mechanical ventilation as well as the reference values in health and disease. The spread of ultrasonographic assessment of diaphragm function may possibly result in timely identification of patients with diaphragm dysfunction and to a potential improvement in the assessment of recovery from diaphragm weakness. Copyright © 2016 by Daedalus Enterprises.

  12. Development of diaphragm automatic homing equipment

    International Nuclear Information System (INIS)

    Kobayashi, Hidetoshi; Yamada, Koji; Moriya, Shinichi; Koike, Jiro; Okabe, Masao; Oyama, Akihiro.

    1996-01-01

    In steam-turbine overhaul inspection, one of the most important processes is to remove rust and deposited contaminants on the surface of turbine parts, while the turbine is in operation, to recover thermal efficiency and prepare good surface conditions for color penetrant inspection. These processes generally are done by dry honing, but this generates dust. To protect laborers against these conditions, Hitachi, Ltd. has developed automatic honing equipment for the diaphragms of the nuclear steam turbine. This equipment was first used in the first annual inspection and overhaul of Hamaoka Nuclear Power Plant No.4 of Chubu Electric Power Inc. (author)

  13. Evaluation of Effective Diaphragm Area for Pneumatic Actuator

    International Nuclear Information System (INIS)

    Ryu, Hogeun; Han, Bongsub; Seon, Juhyoung

    2016-01-01

    The purpose of this study is to develop a methodology to calculate the exact effective diaphragm area using the results of diagnostic test to be performed in the evaluation of air operated valve performance. By using this developed methodology in pneumatic actuator performance evaluation, it can be reduce the possible errors arising from effective diaphragm area in the evaluation of performance of air operated valves. The performance assessment for the operability and structural integrity of air operated valves for the domestic nuclear power plant is in progress. One of the important parameters that determine the performance of the air operated valves is the effective diaphragm area of diaphragm type actuator. The effective diaphragm area is the actual area which the air pressure acting on the diaphragm. In general, the effective diaphragm area used for the performance evaluation of pneumatic actuator is provided by the manufacture or the actuator drawing. Flat type diaphragm was showed the difference between the measured value of EDA and the manufacture’s value, in the case of convoluted type diaphragm has showed that the measured value of EDA and manufacture’s value is almost the same. When evaluate a performance of a diaphragm actuator, accurate EDA is to be used because it is an important variable affecting the actuator performance. Particularly in the case of flat type diaphragm which EDA is changed in accordance with the stroke position, by using the EDA evaluation methodology developed in this study to minimize a possible error due to EDA when evaluating the performance of the air actuator

  14. Evaluation of Effective Diaphragm Area for Pneumatic Actuator

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Hogeun; Han, Bongsub; Seon, Juhyoung [SOOSAN INDUSTRIES, Seoul (Korea, Republic of)

    2016-10-15

    The purpose of this study is to develop a methodology to calculate the exact effective diaphragm area using the results of diagnostic test to be performed in the evaluation of air operated valve performance. By using this developed methodology in pneumatic actuator performance evaluation, it can be reduce the possible errors arising from effective diaphragm area in the evaluation of performance of air operated valves. The performance assessment for the operability and structural integrity of air operated valves for the domestic nuclear power plant is in progress. One of the important parameters that determine the performance of the air operated valves is the effective diaphragm area of diaphragm type actuator. The effective diaphragm area is the actual area which the air pressure acting on the diaphragm. In general, the effective diaphragm area used for the performance evaluation of pneumatic actuator is provided by the manufacture or the actuator drawing. Flat type diaphragm was showed the difference between the measured value of EDA and the manufacture’s value, in the case of convoluted type diaphragm has showed that the measured value of EDA and manufacture’s value is almost the same. When evaluate a performance of a diaphragm actuator, accurate EDA is to be used because it is an important variable affecting the actuator performance. Particularly in the case of flat type diaphragm which EDA is changed in accordance with the stroke position, by using the EDA evaluation methodology developed in this study to minimize a possible error due to EDA when evaluating the performance of the air actuator.

  15. Movement of the diaphragm during radiation treatment

    International Nuclear Information System (INIS)

    Nishioka, Masayuki; Fujioka, Tomio; Sakurai, Makoto; Nakajima, Toshifumi; Onoyama, Yasuto.

    1991-01-01

    Movement of the target volume during the exposure to radiation results in decreased accuracy in radiotherapy. We carried out the quantitative evaluation of the movement of the diaphragm during the radiation therapy. Seventy seven patients, who received radiation therapy for lung cancer from December 1988 to February 1990 at the Osaka-prefectural Habikino Hospital, were studied. The movement was recorded with a sonoprinter at the time of treatment planning for radiotherapy, and the length of movement was evaluated at 6 points on the diaphragm. In a study of 402 points in 77 patients, the average movement was 12 mm, and the maximum movement was 40 mm. At the 17% of the points, the movement exceeded 20 mm. The largest movement was observed at the outer point of the right lung. Movement was greater in men than in women. Performance status was not related to the degree of movement. We concluded that in chest and abdominal irradiation, movement caused by respiration is not negligible, and synchronized radiotherapy should be developed in the future. (author)

  16. Inhalation of Budesonide/Formoterol Increases Diaphragm Muscle Contractility

    Directory of Open Access Journals (Sweden)

    Chiyohiko Shindoh

    2012-01-01

    Conclusions: BUD/FORM inhalation has an inotropic effect on diaphragm muscle, protects diaphragm muscle deterioration after endotoxin injection, and inhibits NO production. Increments in muscle contractility with BUD/FORM inhalation are induced through a synergistic effect of an anti-inflammatory agent and 02-agonist.

  17. Hypoxia-induced dysfunction of rat diaphragm: role of peroxynitrite.

    NARCIS (Netherlands)

    Zhu, X.; Heunks, L.M.A.; Versteeg, E.M.M.; Heijden, E. van der; Ennen, L.; Kuppevelt, A.H.M.S.M. van; Vina, J.; Dekhuijzen, P.N.R.

    2005-01-01

    Oxidants may play a role in hypoxia-induced respiratory muscle dysfunction. In the present study we hypothesized that hypoxia-induced impairment in diaphragm contractility is associated with elevated peroxynitrite generation. In addition, we hypothesized that strenuous contractility of the diaphragm

  18. Detecting defects in diaphragm walls prior to excavation

    NARCIS (Netherlands)

    Spruit, R.; Hopman, V.; Van Tol, A.F.; Broere, W.

    2011-01-01

    Recent incidents with leaking diaphragm walls during construction of subway lines in Amsterdam and Rotterdam (Netherlands) have led to reconsideration of the diaphragm wall as a retaining wall construction for deep excavations. In our opinion the joints between the panels are the weak spot. During

  19. Diaphragm disease of the small intestine: an interesting case report.

    Science.gov (United States)

    Ullah, Sana; Ajab, Shereen; Rao, Rajashekhar; Raghunathan, Girish; DaCosta, Philip

    2015-06-01

    Diaphragm disease of small intestine usually presents with nonspecific clinical features. Radiological investigations often fail to differentiate it from small intestinal tumors and inflammatory bowel disease. It is therefore diagnosed on final histology after surgical resection. We hereby report an interesting case of a suspected small bowel tumor later diagnosed as diaphragm disease on histology. © The Author(s) 2014.

  20. Experimental investigation of solar powered diaphragm and helical pumps

    Science.gov (United States)

    For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at mul...

  1. Effect of flexure beam geometry and material on the displacement of piezo actuated diaphragm for micropump

    Science.gov (United States)

    Roopa, R.; Navin Karanth, P.; Kulkarni, S. M.

    2018-02-01

    In this paper, we present a COMSOL analysis of flexure diaphragm for piezo actuated valveless micropump. Diaphragms play an important role in micropumps, till now plane diaphragms are commonly used in micropumps. Use of compliant flexure hinges in diaphragm and other MEMS application is one of the new approach to achieving high deflection in diaphragm at low operating voltage. Flexures hinges in diaphragm acts as simply supported beam. Out-off plane compliance value and stiffness is considered for the selection of proper flexure for diaphragm. Diaphragm material also plays an important role in the diaphragm central deflection. Factor considered for diaphragm material selection is resilience; it is the ratio of yield stress to static modulus. Higher is the resilience will leads to higher deflection generated, it also imparts good compliance. Based on the resilience beryllium copper, stainless steel and brass materials are selected for diaphragm analysis. Simulations have been performed using COMSOL multiphysics. This study reports the effect of flexure hinge geometry and diaphragm material on the central deflection of diaphragms and compared with existing plane diaphragm. Simulation results illustrates that the deflection of three flexure diaphragm with 2mm width and 2mm length flexure is 6.75µm for stainless steel, 10.89 for beryllium copper and 12.10µm for brass, at 140V which is approximately twice that of plane diaphragm deflection. The maximum in both plane and three flexure diaphragm deflection is obtained for brass diaphragm compared to stainless steel and beryllium copper.

  2. Analytical model for an electrostatically actuated miniature diaphragm compressor

    International Nuclear Information System (INIS)

    Sathe, Abhijit A; Groll, Eckhard A; Garimella, Suresh V

    2008-01-01

    This paper presents a new analytical approach for quasi-static modeling of an electrostatically actuated diaphragm compressor that could be employed in a miniature scale refrigeration system. The compressor consists of a flexible circular diaphragm clamped at its circumference. A conformal chamber encloses the diaphragm completely. The membrane and the chamber surfaces are coated with metallic electrodes. A potential difference applied between the diaphragm and the chamber pulls the diaphragm toward the chamber surface progressively from the outer circumference toward the center. This zipping actuation reduces the volume available to the refrigerant gas, thereby increasing its pressure. A segmentation technique is proposed for analysis of the compressor by which the domain is divided into multiple segments for each of which the forces acting on the diaphragm are estimated. The pull-down voltage to completely zip each individual segment is thus obtained. The required voltage for obtaining a specific pressure rise in the chamber can thus be determined. Predictions from the model compare well with other simulation results from the literature, as well as to experimental measurements of the diaphragm displacement and chamber pressure rise in a custom-built setup

  3. Documentation of diaphragmal paralysis with digital subtraction techniques

    International Nuclear Information System (INIS)

    Waggershauser, T.; Muenchen Univ.; Buente, E.; Muenchen Univ.; Kohz, P.; Muenchen Univ.; Fink, U.; Muenchen Univ.

    1992-01-01

    The causative factors for a paresis of the diaphragm are primarily subsequent to operations on lesions of the phrenic nerve or on such mediastinal tumors as lyphomas which result in compression or infiltration of the nerves. (orig.) [de

  4. Acquired relaxation of the right half of the diaphragm

    International Nuclear Information System (INIS)

    Tolmachev, V.V.; Romadanov, A.A.

    1997-01-01

    Case is described of the development of complete relaxation of the right half of diaphragm following inflammatory respiratory disease accompanied by infections neuritis involving right phrenic nerve. Results of biomedical radiography and computerized tomography in dynamics are presented

  5. Assessing the need for intermediate diaphragms in prestressed concrete bridges.

    Science.gov (United States)

    2008-03-01

    Reinforced concrete intermediate diaphragms (IDs) are currently being used in prestressed concrete (PC) girder bridges in Louisiana. Some of the advantages of providing IDs are disputed in the bridge community; the use of IDs increases the cost and t...

  6. Stylus type MEMS texture sensor covered with corrugated diaphragm

    Science.gov (United States)

    Tsukamoto, Takashiro; Asao, Hideaki; Tanaka, Shuji

    2017-09-01

    In this paper, a stylus type MEMS texture sensor covered with a corrugated palylene diaphragm, which prevent debris from jamming into the sensor without significant degradation of sensitivity and bandwidth, was reported. A new fabrication process using a lost-foil method to make the corrugated diaphragm on a 3-axis piezoresistive force sensor at wafer level has been developed. The texture sensor could detect the surface microstructure as small as about 10 \

  7. Hyperglycemia-induced diaphragm weakness is mediated by oxidative stress

    Science.gov (United States)

    2014-01-01

    Introduction A major consequence of ICU-acquired weakness (ICUAW) is diaphragm weakness, which prolongs the duration of mechanical ventilation. Hyperglycemia (HG) is a risk factor for ICUAW. However, the mechanisms underlying HG-induced respiratory muscle weakness are not known. Excessive reactive oxygen species (ROS) injure multiple tissues during HG, but only one study suggests that excessive ROS generation may be linked to HG-induced diaphragm weakness. We hypothesized that HG-induced diaphragm dysfunction is mediated by excessive superoxide generation and that administration of a specific superoxide scavenger, polyethylene glycol superoxide dismutase (PEG-SOD), would ameliorate these effects. Methods HG was induced in rats using streptozotocin (60 mg/kg intravenously) and the following groups assessed at two weeks: controls, HG, HG + PEG-SOD (2,000U/kg/d intraperitoneally for seven days), and HG + denatured (dn)PEG-SOD (2000U/kg/d intraperitoneally for seven days). PEG-SOD and dnPEG-SOD were administered on day 8, we measured diaphragm specific force generation in muscle strips, force-pCa relationships in single permeabilized fibers, contractile protein content and indices of oxidative stress. Results HG reduced diaphragm specific force generation, altered single fiber force-pCa relationships, depleted troponin T, and increased oxidative stress. PEG-SOD prevented HG-induced reductions in diaphragm specific force generation (for example 80 Hz force was 26.4 ± 0.9, 15.4 ± 0.9, 24.0 ± 1.5 and 14.9 ± 0.9 N/cm2 for control, HG, HG + PEG-SOD, and HG + dnPEG-SOD groups, respectively, P hyperglycemia-induced diaphragm dysfunction. This new mechanistic information could explain how HG alters diaphragm function during critical illness. PMID:24886999

  8. Paper-thinned diaphragm: CT sign of diaphragmatic eventration

    International Nuclear Information System (INIS)

    Im, Jung Gi; Han, Man Chung; Kim, Chu Wan; Shim, Young Soo

    1990-01-01

    CT findings of total left hemidiaphragmatic eventration in two adult patients are described. Chest radiograph showed elevated left hemidiaphragm and left hilum. Paper-thinned muscular portion of the diseased diaphragm was clearly demonstrated with CT scan. With demonstration of paper-thinned diaphragm by CT scan, differentiation of the diaphragmatic eventration from recent onset phrenic nerve paralysis by tumor invasion or from post-traumatic diaphragmatic hernia can be made

  9. Paper-thinned diaphragm: CT sign of diaphragmatic eventration

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jung Gi; Han, Man Chung; Kim, Chu Wan; Shim, Young Soo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    1990-10-15

    CT findings of total left hemidiaphragmatic eventration in two adult patients are described. Chest radiograph showed elevated left hemidiaphragm and left hilum. Paper-thinned muscular portion of the diseased diaphragm was clearly demonstrated with CT scan. With demonstration of paper-thinned diaphragm by CT scan, differentiation of the diaphragmatic eventration from recent onset phrenic nerve paralysis by tumor invasion or from post-traumatic diaphragmatic hernia can be made.

  10. Mechanics of the canine diaphragm in pleural effusion.

    Science.gov (United States)

    De Troyer, André; Leduc, Dimitri; Cappello, Matteo; Gevenois, Pierre Alain

    2012-09-01

    Pleural effusion is a complicating feature of many diseases of the lung and pleura, but its effects on the mechanics of the diaphragm have not been assessed. In the present study, radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in anesthetized dogs, and the three-dimensional location of the markers during relaxation before and after the stepwise introduction of liquid into the left or right pleural space and during phrenic nerve stimulation in the same conditions was determined using computed tomography. From these data, accurate measurements of diaphragm muscle length and displacement were obtained, and the changes in pleural and abdominal pressure were analyzed as functions of these parameters. The effect of liquid instillation on the axial position of rib 5 was also measured. The data showed that 1) liquid leaked through the dorsal mediastinal sheet behind the pericardium so that effusion was bilateral; 2) effusion caused a caudal displacement of the relaxed diaphragm; 3) this displacement was, compared with passive lung inflation, much larger than the cranial displacement of the ribs; and 4) the capacity of the diaphragm to generate pressure, in particular pleural pressure, decreased markedly as effusion increased, and this decrease was well explained by the decrease in active muscle length. It is concluded that pleural effusion has a major adverse effect on the pressure-generating capacity of the diaphragm and that this is the result of the action of hydrostatic forces on the muscle.

  11. Diaphragm pacing improves sleep in patients with amyotrophic lateral sclerosis.

    Science.gov (United States)

    Gonzalez-Bermejo, Jesus; Morélot-Panzini, Capucine; Salachas, François; Redolfi, Stefania; Straus, Christian; Becquemin, Marie-Hélène; Arnulf, Isabelle; Pradat, Pierre-François; Bruneteau, Gaëlle; Ignagni, Anthony R; Diop, Moustapha; Onders, Raymond; Nelson, Teresa; Menegaux, Fabrice; Meininger, Vincent; Similowski, Thomas

    2012-01-01

    In amyotrophic lateral sclerosis (ALS) patients, respiratory insufficiency is a major burden. Diaphragm conditioning by electrical stimulation could interfere with lung function decline by promoting the development of type 1 muscle fibres. We describe an ancillary study to a prospective, non-randomized trial (NCT00420719) assessing the effects of diaphragm pacing on forced vital capacity (FVC). Sleep-related disturbances being early clues to diaphragmatic dysfunction, we postulated that they would provide a sensitive marker. Stimulators were implanted laparoscopically in the diaphragm close to the phrenic motor point in 18 ALS patients for daily conditioning. ALS functioning score (ALSFRS), FVC, sniff nasal inspiratory pressure (SNIP), and polysomnographic recordings (PSG, performed with the stimulator turned off) were assessed before implantation and after four months of conditioning (n = 14). Sleep efficiency improved (69 ± 15% to 75 ± 11%, p = 0.0394) with fewer arousals and micro-arousals. This occurred against a background of deterioration as ALSFRS-R, FVC, and SNIP declined. There was, however, no change in NIV status or the ALSFRS respiratory subscore, and the FVC decline was mostly due to impaired expiration. Supporting a better diaphragm function, apnoeas and hypopnoeas during REM sleep decreased. In conclusion, in these severe patients not expected to experience spontaneous improvements, diaphragm conditioning improved sleep and there were hints at diaphragm function changes.

  12. Four-Dimensional CT of the Diaphragm in Children: Initial Experience

    Science.gov (United States)

    2018-01-01

    Objective To evaluate the technical feasibility of four-dimensional (4D) CT for the functional evaluation of the pediatric diaphragm. Materials and Methods In 22 consecutive children (median age 3.5 months, age range 3 days–3 years), 4D CT was performed to assess diaphragm motion. Diaphragm abnormalities were qualitatively evaluated and diaphragm motion was quantitatively measured on 4D CT. Lung density changes between peak inspiration and expiration were measured in the basal lung parenchyma. The diaphragm motions and lung density changes measured on 4D CT were compared between various diaphragm conditions. In 11 of the 22 children, chest sonography was available for comparison. Results Four-dimensional CT demonstrated normal diaphragm (n = 8), paralysis (n = 10), eventration (n = 3), and diffusely decreased motion (n = 1). Chest sonography demonstrated normal diaphragm (n = 2), paralysis (n = 6), eventration (n = 2), and right pleural effusion (n = 1). The sonographic findings were concordant with the 4D CT findings in 90.9% (10/11) of the patients. In diaphragm paralysis, the affected diaphragm motion was significantly decreased compared with the contralateral normal diaphragm motion (−1.1 ± 2.2 mm vs. 7.6 ± 3.8 mm, p = 0.005). The normal diaphragms showed significantly greater motion than the paralyzed diaphragms (4.5 ± 2.1 mm vs. −1.1 ± 2.2 mm, p Hounsfield units [HU] vs. 180 ± 71 HU, p = 0.03), while no significant differences were found between the normal diaphragms and the paralyzed diaphragms (136 ± 66 HU vs. 89 ± 73 HU, p = 0.1) or between the normal diaphragms and the contralateral normal diaphragms in paralysis (136 ± 66 HU vs. 180 ± 71 HU, p = 0.1). Conclusion The functional evaluation of the pediatric diaphragm is feasible with 4D CT in select children. PMID:29354007

  13. Idiopathic diaphragmatic paralysis: Bell's palsy of the diaphragm?

    Science.gov (United States)

    Crausman, Robert S; Summerhill, Eleanor M; McCool, F Dennis

    2009-01-01

    Idiopathic diaphragm paralysis is probably more common and responsible for more morbidity than generally appreciated. Bell's palsy, or idiopathic paralysis of the seventh cranial nerve, may be seen as an analogous condition. The roles of zoster sine herpete and herpes simplex have increasingly been recognized in Bell's palsy, and there are some data to suggest that antiviral therapy is a useful adjunct to steroid therapy. Thus, we postulated that antiviral therapy might have a positive impact on the course of acute idiopathic diaphragm paralysis which is likely related to viral infection. Three consecutive patients with subacute onset of symptomatic idiopathic hemidiaphragm paralysis were empirically treated with valacyclovir, 1,000 mg twice daily for 1 week. Prior to therapy, diaphragmatic function was assessed via pulmonary function testing and two-dimensional B-mode ultrasound, with testing repeated 1 month later. Diaphragmatic function pre- and post-treatment was compared to that of a historical control group of 16 untreated patients. All three subjects demonstrated ultrasound recovery of diaphragm function 4-6 weeks following treatment with valacyclovir. This recovery was accompanied by improvements in maximum inspiratory pressure (PI(max)) and vital capacity (VC). In contrast, in the untreated cohort, diaphragm recovery occurred in only 11 subjects, taking an average of 14.9 +/- 6.1 months (mean +/- SD). The results of this small, preliminary study suggest that antiviral therapy with valacyclovir may be helpful in the treatment of idiopathic diaphragm paralysis induced by a viral infection.

  14. Giant flexoelectric polarization in a micromachined ferroelectric diaphragm

    KAUST Repository

    Wang, Zhihong

    2012-08-14

    The coupling between dielectric polarization and strain gradient, known as flexoelectricity, becomes significantly large on the micro- and nanoscale. Here, it is shown that giant flexoelectric polarization can reverse remnant ferroelectric polarization in a bent Pb(Zr0.52Ti0.48) O3 (PZT) diaphragm fabricated by micromachining. The polarization induced by the strain gradient and the switching behaviors of the polarization in response to an external electric field are investigated by observing the electromechanical coupling of the diaphragm. The method allows determination of the absolute zero polarization state in a PZT film, which is impossible using other existing methods. Based on the observation of the absolute zero polarization state and the assumption that bending of the diaphragm is the only source of the self-polarization, the upper bound of flexoelectric coefficient of PZT film is calculated to be as large as 2.0 × 10-4 C m -1. The strain gradient induced by bending the diaphragm is measured to be on the order of 102 m-1, three orders of magnitude larger than that obtained in the bulk material. Because of this large strain gradient, the estimated giant flexoelectric polarization in the bent diaphragm is on the same order of magnitude as the normal remnant ferroelectric polarization of PZT film. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Effect of maternal steroid on developing diaphragm integrity.

    Directory of Open Access Journals (Sweden)

    Yong Song

    Full Text Available Antenatal steroids reduce the severity of initial respiratory distress of premature newborn babies but may have an adverse impact on other body organs. The study aimed to examine the effect of maternal steroids on postnatal respiratory muscle function during development and elucidate the mechanisms underlying the potential myopathy in newborn rats. Pregnant rats were treated with intramuscular injections of 0.5 mg/kg betamethasone 7 d and 3 d before birth. Newborn diaphragms were dissected for assessment of contractile function at 2 d, 7 d or 21 d postnatal age (PNA, compared with age-matched controls. The expression of myosin heavy chain (MHC isoforms and atrophy-related genes and activity of intracellular molecular signalling were measured using quantitative PCR and/or Western blot. With advancing PNA, neonatal MHC gene expression decreased progressively while MHC IIb and IIx isoforms increased. Protein metabolic signalling showed high baseline activity at 2 d PNA, and significantly declined at 7 d and 21 d. Antenatal administration of betamethasone significantly decreased diaphragm force production, fatigue resistance, total fast fibre content and anabolic signalling activity (Akt and 4E-BP1 in 21 d diaphragm. These responses were not observed in 2 d or 7 d postnatal diaphragm. Results demonstrate that maternal betamethasone treatment causes postnatal diaphragmatic dysfunction at 21 d PNA, which is attributed to MHC II protein loss and impairment of the anabolic signalling pathway. Developmental modifications in MHC fibre composition and protein signalling account for the age-specific diaphragm dysfunction.

  16. A novel technique for diaphragm biopsies in human patients.

    Science.gov (United States)

    Noullet, Séverine; Romero, Norma; Menegaux, Fabrice; Chapart, Maud; Demoule, Alexandre; Morelot-Panzini, Capucine; Similowski, Thomas; Gonzalez-Bermejo, Jésus

    2015-06-15

    The diaphragm is difficult to biopsy because of its anatomic location. We describe a new laparoscopic diaphragm biopsy technique. Fifty one patients with amyotrophic lateral sclerosis gave their consent to diaphragm biopsy in the context of an implanted phrenic nerve stimulation protocol (NCT01583088). The biopsy was taken from the costal diaphragm, after opening the parietal peritoneum with scissors, and by grasping the diaphragmatic muscle over the rib with toothed laparoscopy forceps. The first four electrocoagulation biopsies were unsuitable for morphologic examination. The following 47 biopsies were therefore performed without electrocoagulation. The mean size of the biopsy fragments obtained after preparation was 3 ± 1 × 2 ± 1 × 1 ± 1 mm (maximum: 4 × 3 × 2 mm). A diaphragmatic injury occurred during the section in three cases requiring immediate suture without causing pneumothorax. A small pleural effusion was observed on the postoperative chest x-ray in one patient with a spontaneously favorable outcome. Numerous stains were able to be performed on the fragments obtained. Diaphragm biopsy can be safely performed by laparoscopy and yields tissue suitable for our future histologic evaluation. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Bending-Induced Giant Polarization in Ferroelectric MEMS Diaphragm

    KAUST Repository

    Wang, Zhihong

    2016-09-09

    The polarization induced by the strain gradient, i.e. the flexoelectric effect, has been observed in a micromachined Pb(Zr0.52Ti0.48)O3 (PZT) diaphragms. Applying air pressure to bend a flat diaphragm which initially does not exhibit any electromechanical coupling can induce a resonance peak in its impedance spectrum. This result supposes that bending, thus the strain gradient in the diaphragm causes polarization in PZT film. We also investigated the switching behaviors of the polarization in response to an external electric field in a bent diaphragm and further quantified the polarization induced by the strain gradient. The effective flexoelectric coefficient of the PZT film has been calculated as large as 2.0 × 10−4 C/m. A giant flexoelectric polarization of the order of 1 μC/cm2 was characterized which is of the same order of magnitude as the normal remnant ferroelectric polarization of PZT film. The suggested explanation for the giant polarization is the large strain gradient in the diaphragm and the strain gradient induced reorientation of the polar nanodomains.

  18. Plasma Discharge Process in a Pulsed Diaphragm Discharge System

    Science.gov (United States)

    Duan, Jianjin; Hu, Jue; Zhang, Chao; Wen, Yuanbin; Meng, Yuedong; Zhang, Chengxu

    2014-12-01

    As one of the most important steps in wastewater treatment, limited study on plasma discharge process is a key challenge in the development of plasma applications. In this study, we focus on the plasma discharge process of a pulsed diaphragm discharge system. According to the analysis, the pulsed diaphragm discharge proceeds in seven stages: (1) Joule heating and heat exchange stage; (2) nucleated site formation; (3) plasma generation (initiation of the breakdown stage); (4) avalanche growth and plasma expansion; (5) plasma contraction; (6) termination of the plasma discharge; and (7) heat exchange stage. From this analysis, a critical voltage criterion for breakdown is obtained. We anticipate this finding will provide guidance for a better application of plasma discharges, especially diaphragm plasma discharges.

  19. CFD analysis of a diaphragm free-piston Stirling cryocooler

    Science.gov (United States)

    Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

    2016-10-01

    This paper presents a Computational Fluid Dynamics (CFD) analysis of a novel free-piston Stirling cryocooler that uses a pair of metal diaphragms to seal and suspend the displacer. The diaphragms allow the displacer to move without rubbing or moving seals. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicated the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. The diaphragm's large diameter and short stroke produces a significant radial component to the oscillating flow fields inside the cryocooler which were not modelled in the one-dimensional analysis tool Sage that was used to design the prototypes. Compared with standard pistons, the diaphragm geometry increases the gas-to-wall heat transfer due to the higher velocities and smaller hydraulic diameters. A Computational Fluid Dynamics (CFD) model of the cryocooler was constructed to understand the underlying fluid-dynamics and heat transfer mechanisms with the aim of further improving performance. The CFD modelling of the heat transfer in the radial flow fields created by the diaphragms shows the possibility of utilizing the flat geometry for heat transfer, reducing the need for, and the size of, expensive heat exchangers. This paper presents details of a CFD analysis used to model the flow and gas-to-wall heat transfer inside the second prototype cryocooler, including experimental validation of the CFD to produce a robust analysis.

  20. Is Diaphragm Motion a Good Surrogate for Liver Tumor Motion?

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Juan [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Cai, Jing [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Wang, Hongjun [School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Chang, Zheng; Czito, Brian G. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Bashir, Mustafa R. [Department of Radiology, Duke University Medical Center, Durham, North Carolina (United States); Palta, Manisha [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yin, Fang-Fang, E-mail: fangfang.yin@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2014-11-15

    Purpose: To evaluate the relationship between liver tumor motion and diaphragm motion. Methods and Materials: Fourteen patients with hepatocellular carcinoma (10 of 14) or liver metastases (4 of 14) undergoing radiation therapy were included in this study. All patients underwent single-slice cine–magnetic resonance imaging simulations across the center of the tumor in 3 orthogonal planes. Tumor and diaphragm motion trajectories in the superior–inferior (SI), anterior–posterior (AP), and medial–lateral (ML) directions were obtained using an in-house-developed normalized cross-correlation–based tracking technique. Agreement between the tumor and diaphragm motion was assessed by calculating phase difference percentage, intraclass correlation coefficient, and Bland-Altman analysis (Diff). The distance between the tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between the 2 motions. Results: Of all patients, the mean (±standard deviation) phase difference percentage values were 7.1% ± 1.1%, 4.5% ± 0.5%, and 17.5% ± 4.5% in the SI, AP, and ML directions, respectively. The mean intraclass correlation coefficient values were 0.98 ± 0.02, 0.97 ± 0.02, and 0.08 ± 0.06 in the SI, AP, and ML directions, respectively. The mean Diff values were 2.8 ± 1.4 mm, 2.4 ± 1.1 mm, and 2.2 ± 0.5 mm in the SI, AP, and ML directions, respectively. Tumor and diaphragm motions had high concordance when the distance between the tumor and tracked diaphragm area was small. Conclusions: This study showed that liver tumor motion had good correlation with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be used as a reliable surrogate for liver tumor motion.

  1. Experimental device for measuring the dynamic properties of diaphragm motors

    Science.gov (United States)

    Fojtášek, Kamil; Dvořák, Lukáš; Mejzlík, Jan

    The subject of this paper is to design and description of the experimental device for the determination dynamic properties of diaphragm pneumatic motors. These motors are structurally quite different from conventional pneumatic linear cylinders. The working fluid is typically compressed air, the piston of motor is replaced by an elastic part and during the working cycle there is a contact of two elastic environments. In the manufacturers catalogs of these motors are not given any working characteristics. Description of the dynamic behavior of diaphragm motor will be used for verification of mathematical models.

  2. Radiofrequency ablation of pulmonary tumors near the diaphragm.

    Science.gov (United States)

    Iguchi, T; Hiraki, T; Gobara, H; Fujiwara, H; Sakurai, J; Matsui, Y; Mitsuhashi, T; Toyooka, S; Kanazawa, S

    To retrospectively evaluate the feasibility, safety, and efficacy of radiofrequency ablation (RFA) of lung tumors located near the diaphragm. A total of 26 patients (15 men, 11 women; mean age, 61.5 years±13.0 [SD]) with a total of 29 lung tumors near the diaphragm (i.e., distance<10mm) were included. Mean tumor diameter was 11.0mm±5.3 (SD) (range, 2-23mm). Efficacy of RFA, number of adverse events and number of adverse events with a grade≥3, based on the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0, were compared between patients with lung tumors near the diaphragm and a control group of patients with more distally located lung tumors (i.e., distance≥10mm). RFA was technically feasible for all tumors near the diaphragm. Four grade 3 adverse events (1 pneumothorax requiring pleurodesis and 3 phrenic nerve injuries) were observed. No grade≥4 adverse events were reported. The median follow-up period for tumors near the diaphragm was 18.3 months. Local progression was observed 3.3 months after RFA in 1 tumor. The technique efficacy rates were 96.2% at 1 year and 96.2% at 2 years and were not different, from those observed in control subjects (186 tumors; P=0.839). Shoulder pain (P<0.001) and grade 1 pleural effusion (P<0.001) were more frequently observed in patients with lung tumor near the diaphragm. The rates of grade≥3 adverse events did not significantly differ between tumors near the diaphragm (4/26 sessions) and the controls (7/133 sessions) (P=0.083). RFA is a feasible and effective therapeutic option for lung tumors located near the diaphragm. However, it conveys a higher rate of shoulder pain and asymptomatic pleural effusion by comparison with more distant lung tumors. Copyright © 2017 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  3. Diaphragm electromyographic activity following unilateral midcervical contusion injury in rats

    Science.gov (United States)

    Sieck, Gary C.

    2016-01-01

    Contusion-type injuries to the spinal cord are characterized by tissue loss and disruption of spinal pathways. Midcervical spinal cord injuries impair the function of respiratory muscles and may contribute to significant respiratory complications. This study systematically assessed the impact of a 100-kDy unilateral C4 contusion injury on diaphragm muscle activity across a range of motor behaviors in rats. Chronic diaphragm electromyography (EMG) was recorded before injury and at 1 and 7 days postinjury (DPI). Histological analyses assessed the extent of perineuronal net formation, white-matter sparing, and phrenic motoneuron loss. At 7 DPI, ∼45% of phrenic motoneurons were lost ipsilaterally. Relative diaphragm root mean square (RMS) EMG activity increased bilaterally across a range of motor behaviors by 7 DPI. The increase in diaphragm RMS EMG activity was associated with an increase in neural drive (RMS value at 75 ms after the onset of diaphragm activity) and was more pronounced during higher force, nonventilatory motor behaviors. Animals in the contusion group displayed a transient decrease in respiratory rate and an increase in burst duration at 1 DPI. By 7 days, following midcervical contusion, there was significant perineuronal net formation and white-matter loss that spanned 1 mm around the injury epicenter. Taken together, these findings are consistent with increased recruitment of remaining motor units, including more fatigable, high-threshold motor units, during higher force, nonventilatory behaviors. Changes in diaphragm EMG activity following midcervical contusion injury reflect complex adaptations in neuromotor control that may increase the risk of motor-unit fatigue and compromise the ability to sustain higher force diaphragm efforts. NEW & NOTEWORTHY The present study shows that unilateral contusion injury at C4 results in substantial loss of phrenic motoneurons but increased diaphragm muscle activity across a range of ventilatory and higher

  4. Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap

    Science.gov (United States)

    ... ACOG Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap Home For Patients Search ... Format Barrier Methods of Birth Control: Spermicide, Condom, Sponge, Diaphragm, and Cervical Cap Contraception What are barrier ...

  5. Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm

    KAUST Repository

    Wang, Zhihong

    2013-11-04

    We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr 0.52 Ti 0.48)O 3 (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC voltage. The curvature of the diaphragm was controlled by applying air pressure to its back. We found that a depolarized flat diaphragm does not initially exhibit electromechanical coupling or the piezoelectric response. However, upon the application of static air pressure to the diaphragm, both electromechanical coupling and the piezoelectric response can be induced in the originally depolarized diaphragm. The piezoelectric response increases as the curvature increases and a giant piezoelectric response can be obtained from a bent diaphragm. The obtained results clearly demonstrate that a high strain gradient in a diaphragm can polarize a PZT film through a flexoelectric effect, and that the induced piezoelectric response of the diaphragm can be controlled by adjusting its curvature.

  6. Diaphragm atrophy and weakness in the absence of mitochondrial dysfunction in the critically Ill

    NARCIS (Netherlands)

    Van den Berg, Marloes; Hooijman, Pleuni E.; Beishuizen, Albertus; De Waard, Monique C.; Paul, Marinus A.; Hartemink, Koen J.; Van Hees, Hieronymus W.H.; Lawlor, Michael W.; Brocca, Lorenza; Bottinelli, Roberto; Pellegrino, Maria A.; Stienen, Ger J.M.; Heunks, Leo M.A.; Wüst, Rob C.I.; Ottenheijm, Coen A.C.

    2017-01-01

    Rationale: The clinical significance of diaphragm weakness in critically ill patients is evident: it prolongs ventilator dependency and increases morbidity, duration of hospital stay, and health care costs. The mechanisms underlying diaphragm weakness are unknown, but might include mitochondrial

  7. Diaphragm Muscle Fiber Weakness and Ubiquitin-Proteasome Activation in Critically Ill Patients

    NARCIS (Netherlands)

    Hooijman, P.E.; Beishuizen, A.; Witt, C.C.; de Waard, M.C.; Girbes, A.R.J.; Spoelstra-de Man, A.M.E.; Niessen, H.W.; Manders, E.; van Hees, H.W.H.; van den Brom, C.E.; Silderhuis, V.; Lawlor, M.W.; Labeit, S.; Stienen, G.J.M.; Hartemink, K.J.; Paul, M.A.; Heunks, L.M.A.; Ottenheijm, C.A.C.

    2015-01-01

    RATIONALE: The clinical significance of diaphragm weakness in critically ill patients is evident: it prolongs ventilator dependency, and increases morbidity and duration of hospital stay. To date, the nature of diaphragm weakness and its underlying pathophysiologic mechanisms are poorly understood.

  8. Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges.

    Science.gov (United States)

    2004-10-01

    Continuity diaphragms used on skewed bents in prestressed girder bridges cause difficulties in detailing and : construction. Details for bridges with large diaphragm skew angles (>30) have not been a problem for LA DOTD. : However, as the skew angl...

  9. Validation of ultrasonography for non-invasive assessment of diaphragm function in muscular dystrophy.

    Science.gov (United States)

    Whitehead, Nicholas P; Bible, Kenneth L; Kim, Min Jeong; Odom, Guy L; Adams, Marvin E; Froehner, Stanley C

    2016-12-15

    Duchenne muscular dystrophy (DMD) is a severe, degenerative muscle disease that is commonly studied using the mdx mouse. The mdx diaphragm muscle closely mimics the pathophysiological changes in DMD muscles. mdx diaphragm force is commonly assessed ex vivo, precluding time course studies. Here we used ultrasonography to evaluate time-dependent changes in diaphragm function in vivo, by measuring diaphragm movement amplitude. In mdx mice, diaphragm amplitude decreased with age and values were much lower than for wild-type mice. Importantly, diaphragm amplitude strongly correlated with ex vivo specific force values. Micro-dystrophin administration increased mdx diaphragm amplitude by 26% after 4 weeks. Diaphragm amplitude correlated positively with ex vivo force values and negatively with diaphragm fibrosis, a major cause of DMD muscle weakness. These studies validate diaphragm ultrasonography as a reliable technique for assessing time-dependent changes in mdx diaphragm function in vivo. This technique will be valuable for testing potential therapies for DMD. Duchenne muscular dystrophy (DMD) is a severe, degenerative muscle disease caused by dystrophin mutations. The mdx mouse is a widely used animal model of DMD. The mdx diaphragm muscle most closely recapitulates key features of DMD muscles, including progressive fibrosis and considerable force loss. Diaphragm function in mdx mice is commonly evaluated by specific force measurements ex vivo. While useful, this method only measures force from a small muscle sample at one time point. Therefore, accurate assessment of diaphragm function in vivo would provide an important advance to study the time course of functional decline and treatment benefits. Here, we evaluated an ultrasonography technique for measuring time-dependent changes of diaphragm function in mdx mice. Diaphragm movement amplitude values for mdx mice were considerably lower than those for wild-type, decreased from 8 to 18 months of age, and correlated

  10. Rectal diaphragm in a patient with imperforate anus and rectoprostatic fistula

    Directory of Open Access Journals (Sweden)

    Thakur Ashokanand

    2009-01-01

    Full Text Available The association of rectal diaphragm in an imperforate anus has not been reported until now. A 1-year-old male presented with right transverse colostomy for high anorectal malformation. The patient had imperforate anus and a recto-prostatic fistula with rectal diaphragm. We managed the case by an ano-rectal pull through with excision of the diaphragm.

  11. A monitoring device for pressurised-air-driven diaphragm-based artificial heart assist devices

    NARCIS (Netherlands)

    Hoeben, F.P.; Hoeben, F.P.; de Mul, F.F.M.; Stokkink, J.S.D.; Stokkink, H.S.D.; Koelink, M.H.; Koelink, M.H.; Greve, Jan

    1992-01-01

    A non-invasive device has been developed to monitor the diaphragm position and the blood flow in artificial heart assist devices equipped with a pressurised-air-driven diaphragm. Light scattering from the diaphragm is used as a mechanism for measuring. Information about the position of several

  12. Phrenic nerves and diaphragms in sudden infant death syndrome.

    Science.gov (United States)

    Weis, J; Weber, U; Schröder, J M; Lemke, R; Althoff, H

    1998-01-30

    Disturbances of the respiratory system may be an important factor in the cascade of events leading to sudden infant death syndrome (SIDS). Even though the diaphragm is the major respiratory muscle in infants, little is known about alterations of this muscle and of the phrenic nerve in SIDS. In the present study, diaphragms and phrenic nerves of 24 SIDS infants and seven controls were analyzed. Morphometric analysis revealed only slightly larger cross sectional areas of phrenic nerve axons but no increase in myelin sheath thickness in SIDS cases. However, in one SIDS case, myelinated nerve fibre density was severely reduced. Using electron microscopy, several nerve fibres of SIDS infants showed focal accumulations of neurofilaments. Muscle fibre diameters in SIDS diaphragms were significantly larger compared to controls (P fibre ruptures and contracture bands were found. These prominent nonspecific ultrastructural alterations should advise caution in the interpretation of morphometric data. Thus, in some cases exemplified by one case of the present series, decreased density of phrenic nerve myelinated axons might contribute to SIDS. Still, the present results indicate that development of phrenic nerves and diaphragms is not delayed in most SIDS infants.

  13. Traumatic rupture of the diaphragm | Jamabo | Sahel Medical Journal

    African Journals Online (AJOL)

    Those treated for traumatic rupture of the diaphragm were selected and analyzed for age, gender, cause of injury, associated injuries sustained and mode of treatment. They were all treated at the University of Port Harcourt Teaching Hospital and a private clinic in Port Harcourt. Results: 12 patients had traumatic rupture of ...

  14. Potential for Revitalisation of the Diaphragm for Family Planning in ...

    African Journals Online (AJOL)

    This health systems assessment evaluated the feasibility of introducing a new contraceptive device, the SILCS single-size diaphragm, into the existing family planning method mix in Uganda. A total of 26 focus group discussions with 201 female and 77 male potential users and 98 key informant interviews with policymakers ...

  15. Subacute presentation of spontaneous diaphragmal rupture: case report

    Directory of Open Access Journals (Sweden)

    Dejan Hermann

    2005-07-01

    Full Text Available Background: Diaphragmatic injuries are relatively rare and present with non specific symptoms and signs. Late discoveries are almost a rule in all but the most evident cases. Many patients are observed or even treated for suspected other conditions, most often musculosceletal disorders.Patients and methods: We report a case of a 14-year-old boy who presented with left lumbar pain and developed peritonitis six days after strenuous training. A chest X-ray revealed abdominal viscera in the left hemithorax. A large posterolateral rupture of the left diaphragm was found at laparotomy together with herniation of the stomach, spleen and colon. The stomach was perforated and partialy necrotic. Afer partial gastrectomy, repositioning and diaphragmal repair the patient recovered well.Conclusions: If pain in toracoabdominal region is a predominant sign after trauma or endogenous strain, one should consider the posibility of ruptured diaphragm and make a chest X-ray. Operation of diaphragmal hernia is necessary and garanties good results when treated on time.

  16. Potential for Revitalisation of the Diaphragm for Family Planning in ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    diaphragm, into the existing family planning method mix in Uganda. A total of 26 ... expand women's options for contraceptive protection. ... several countries, and the product was approved in ..... younger clients and may not adequately market ... different stages of their life cycle. .... maternal mortality ratio in Uganda: priority.

  17. A new straight accelerator tube with U diaphragm

    International Nuclear Information System (INIS)

    Liu Jinhong; Lai Weiquan; Deng Yushen; Zhang Jidong

    1994-01-01

    After calculating the potential distribution and the particle trajectories in electrostatic accelerator tubes, a new straight tube with U diaphragm to suppress secondary particles is proposed. It's properties are demonstrated by the high voltage tests and the γ-rays measurements in the accelerator

  18. Design and analysis of diaphragms in dynamic microphones

    Directory of Open Access Journals (Sweden)

    Zi-Gui Huang

    2015-07-01

    Full Text Available Most contemporary high-end microphones are dynamic microphones, adopting the most basic electromagnetic transduction principles. This study investigated the diaphragm structures of dynamic microphones. The diaphragms were composed of polyimide material, and the boundary settings required for actual operation were provided using finite element model analysis software. The characteristic frequencies caused by grooving variations on the three-dimensional diaphragm were analyzed for the various groove shapes and number. The groove angles and width variations were examined based on the optimal groove shape selected in the aforementioned analysis, and the effects of these shapes were determined based on the analytical results. Acoustic waves cause thin films to vibrate, forming the working principle behind dynamic microphones. The thin film drives a coil to vibrate in a magnetic field and cuts the line of magnetic force, subsequently producing a voltage on both ends of the coil. This audio-frequency-inducted voltage represents an acoustic wave message. The finite element model analysis software was used to conduct electromagnetic induction simulations; the sound source was fed to the diaphragm to drive the coil. The coil vibrations caused the line of magnetic force to be cut, and the final voltages produced were examined and compared.

  19. Investigation of PVdF active diaphragms for synthetic jets

    Science.gov (United States)

    Bailo, Kelly C.; Brei, Diann E.; Calkins, Frederick T.

    2000-06-01

    Current research has shown that aircraft can gain significant aerodynamic performance benefits by employing active flow control (AFC). One of the enabling technologies of AFC is the synthetic jet. Synthetic jets, also known as zero-net-mass flux actuators, act as bi-directional pumps injecting high momentum air into the local aerodynamic flow. Previous work has concentrated on high frequency synthetic jets based on piezoelectric active diaphragms such as Thunder actuators. Low frequency synthetic jets present a unique challenge requiring large displacements, which current technology has difficulty meeting. Boeing is investigating novel shaped low frequency synthetic jets that can modify the flow over fixed aircraft wings. This paper present the initial study of two promising active diaphragm concepts: a crescent shape and an opposing bender shape. These active diaphragms were numerically modeled utilizing the general-purpose finite element code ABAQUS. Using the ABAQUS results, the dynamic volume change within each jet was calculated and incorporated into an analytical linear Bernoulli model to predict the velocities and pressures at the nozzle. Simulations were performed to determine trends to assist in selection of prototype configurations. Prototypes of both diaphragm concepts were constructed from polyvinylidene fluoride and experimentally tested at Boeing with promising results.

  20. Effect of hyperinflation on inspiratory function of the diaphragm.

    Science.gov (United States)

    Minh, V D; Dolan, G F; Konopka, R F; Moser, K M

    1976-01-01

    The inspiratory efficiency of the diaphragm during unilateral and bilateral phrenic stimulation (UEPS and BEPS) with constant stimulus was studied in seven dogs from FRC to 120% TLC. Alveolar pressures (PAl) were recorded during relaxation, BEPS and UEPS at each lung volume in the closed respiratory system. From the PAl-lung volume curves, tidal volume (VT), and pressure developed by the diaphragm (Pmus) were derived. Results are summarized below. a) Hyperinflation impaired the inspiratory efficiency of the diaphragm which behaved as an expiratory muscle beyond the lung volume of 103.7% TLC (Vinef). b) The diaphragm during UEPS became expiratory at the same Vinef as during (BEPS. C) The VT-lung volume relationship was linear during BEPS, allowing simple quantitation of VT loss with hyperinflation and prediction of Vinef. d) With only one phrenic nerve stimulated, the functional loss is less pronounced in VT than in Pmus, as compared to BEPS, indicating that the respiratory system was more compliant during UEPS than BEPS. This compliance difference from UEPS to BEPS diminished with severe hyperinflation.

  1. Recruitment of rat diaphragm motor units across motor behaviors with different levels of diaphragm activation.

    Science.gov (United States)

    Seven, Yasin B; Mantilla, Carlos B; Sieck, Gary C

    2014-12-01

    Phrenic motor neurons are recruited across a range of motor behaviors to generate varying levels of diaphragm muscle (DIAm) force. We hypothesized that DIAm motor units are recruited in a fixed order across a range of motor behaviors of varying force levels, consistent with the Henneman Size Principle. Single motor unit action potentials and compound DIAm EMG activities were recorded in anesthetized, neurally intact rats across different motor behaviors, i.e., eupnea, hypoxia-hypercapnia (10% O2 and 5% CO2), deep breaths, sustained airway occlusion, and sneezing. Central drive [estimated by root-mean-squared (RMS) EMG value 75 ms after the onset of EMG activity (RMS75)], recruitment delay, and onset discharge frequencies were similar during eupnea and hypoxia-hypercapnia. Compared with eupnea, central drive increased (∼25%) during deep breaths, and motor units were recruited ∼12 ms earlier (P motor units were recruited ∼30 ms earlier (P motor unit onset discharge frequencies were significantly higher (P Recruitment order of motor unit pairs observed during eupnea was maintained for 98%, 87%, and 84% of the same pairs recorded during hypoxia-hypercapnia, deep breaths, and airway occlusion, respectively. Reversals in motor unit recruitment order were observed primarily if motor unit pairs were recruited motor unit recruitment order being determined primarily by the intrinsic size-dependent electrophysiological properties of phrenic motor neurons. Copyright © 2014 the American Physiological Society.

  2. Evaluation of phrenic nerve and diaphragm function with peripheral nerve stimulation and M-mode ultrasonography in potential pediatric phrenic nerve or diaphragm pacing candidates.

    Science.gov (United States)

    Skalsky, Andrew J; Lesser, Daniel J; McDonald, Craig M

    2015-02-01

    Assessing phrenic nerve function in the setting of diaphragmatic paralysis in diaphragm pacing candidates can be challenging. Traditional imaging modalities and electrodiagnostic evaluations are technically difficult. Either modality alone is not a direct measure of the function of the phrenic nerve and diaphragm unit. In this article, the authors present their method for evaluating phrenic nerve function and the resulting diaphragm function. Stimulating the phrenic nerve with transcutaneous stimulation and directly observing the resulting movement of the hemidiaphragm with M-mode ultrasonography provides quantitative data for predicting the success of advancing technologies such as phrenic nerve pacing and diaphragm pacing. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Failure analysis of globe control valves with spring-diaphragm actuator for nuclear power plant applications

    International Nuclear Information System (INIS)

    Khan, M.R.; Chen, W.W.H.; Wang, T.Y.

    1997-01-01

    The results of the failure analysis of a globe control valve with spring-diaphragm actuator indicated that the diaphragm failed because the service loading is close to the strength of the diaphragm. The resulting impact force is significantly larger than the plug guide strength and that cause it to bulge out after the impact. To improve the valve performance, proper torque should be used to tighten the actuator diaphragm case fasteners. A stronger actuator diaphragm could be used to provide additional safety margin during operation. Stiffening the plug guide may avoid jamming the bushing

  4. Audiovisual biofeedback improves diaphragm motion reproducibility in MRI

    Science.gov (United States)

    Kim, Taeho; Pollock, Sean; Lee, Danny; O’Brien, Ricky; Keall, Paul

    2012-01-01

    Purpose: In lung radiotherapy, variations in cycle-to-cycle breathing results in four-dimensional computed tomography imaging artifacts, leading to inaccurate beam coverage and tumor targeting. In previous studies, the effect of audiovisual (AV) biofeedback on the external respiratory signal reproducibility has been investigated but the internal anatomy motion has not been fully studied. The aim of this study is to test the hypothesis that AV biofeedback improves diaphragm motion reproducibility of internal anatomy using magnetic resonance imaging (MRI). Methods: To test the hypothesis 15 healthy human subjects were enrolled in an ethics-approved AV biofeedback study consisting of two imaging sessions spaced ∼1 week apart. Within each session MR images were acquired under free breathing and AV biofeedback conditions. The respiratory signal to the AV biofeedback system utilized optical monitoring of an external marker placed on the abdomen. Synchronously, serial thoracic 2D MR images were obtained to measure the diaphragm motion using a fast gradient-recalled-echo MR pulse sequence in both coronal and sagittal planes. The improvement in the diaphragm motion reproducibility using the AV biofeedback system was quantified by comparing cycle-to-cycle variability in displacement, respiratory period, and baseline drift. Additionally, the variation in improvement between the two sessions was also quantified. Results: The average root mean square error (RMSE) of diaphragm cycle-to-cycle displacement was reduced from 2.6 mm with free breathing to 1.6 mm (38% reduction) with the implementation of AV biofeedback (p-value biofeedback (p-value biofeedback (p-value = 0.012). The diaphragm motion reproducibility improvements with AV biofeedback were consistent with the abdominal motion reproducibility that was observed from the external marker motion variation. Conclusions: This study was the first to investigate the potential of AV biofeedback to improve the motion

  5. Diaphragm Effect of Steel Space Roof Systems in Hall Structures

    Directory of Open Access Journals (Sweden)

    Mehmet FENKLİ

    2015-09-01

    Full Text Available Hall structures have been used widely for different purposes. They have are reinforced concrete frames and shear wall with steel space roof systems. Earthquake response of hall structures is different from building type structures. One of the most critical nodes is diaphragm effect of steel space roof on earthquake response of hall structures. Diaphragm effect is depending on lateral stiffness capacity of steel space roof system. Lateral stiffness of steel space roof system is related to modulation geometry, support conditions, selected sections and system geometry. In current paper, three representative models which are commonly used in Turkey were taken in to account for investigation. Results of numerical tests were present comparatively

  6. Phrenic Nerve Reconstruction and Bilateral Diaphragm Plication After Lobectomy.

    Science.gov (United States)

    Shinohara, Shuichi; Yamada, Tetsu; Ueda, Mitsuhiro; Ishinagi, Hiroyoshi; Matsuoka, Takahisa; Nagai, Shinjiro; Matsuoka, Katsunari; Miyamoto, Yoshihiro

    2017-07-01

    A 49-year-old man with left phrenic nerve paralysis caused by mediastinal tumor resection 28 years earlier was found to have a nodule in the right upper lobe. The right phrenic nerve was severed during right upper lobectomy but was reconstructed along with bilateral plication of the diaphragm. The patient was weaned from the ventilator during the daytime on postoperative day 13 and was discharged home on postoperative day 48. Three months postoperatively, chest fluoroscopic imaging showed recovery of movement of the right diaphragm. Nerve conduction studies showed improvement of function of the reconstructed right phrenic nerve. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  7. PO2 Cycling Reduces Diaphragm Fatigue by Attenuating ROS Formation

    OpenAIRE

    Zuo, Li; Diaz, Philip T.; Chien, Michael T.; Roberts, William J.; Kishek, Juliana; Best, Thomas M.; Wagner, Peter D.

    2014-01-01

    Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr) followed by a high oxygen level (550 Torr), can reduce intracellular reactive oxygen species (ROS) as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe) was used to monito...

  8. PO2 cycling reduces diaphragm fatigue by attenuating ROS formation.

    Science.gov (United States)

    Zuo, Li; Diaz, Philip T; Chien, Michael T; Roberts, William J; Kishek, Juliana; Best, Thomas M; Wagner, Peter D

    2014-01-01

    Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr) followed by a high oxygen level (550 Torr), can reduce intracellular reactive oxygen species (ROS) as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe) was used to monitor muscular ROS production in real time with confocal microscopy during a lower PO2 condition. In the control group with no PO2 cycling, intracellular ROS formation did not appear during the first 15 min of the low PO2 period. However, after 20 min of low PO2, ROS levels increased significantly by ∼30% compared to baseline, and this increase continued until the end of the 30 min low PO2 condition. Conversely, muscles treated with PO2 cycling showed a complete absence of enhanced fluorescence emission throughout the entire low PO2 period. Furthermore, PO2 cycling-treated diaphragm exhibited increased fatigue resistance during prolonged low PO2 period compared to control. Thus, our data suggest that PO2 cycling mitigates diaphragm fatigue during prolonged low PO2. Although the exact mechanism for this protection remains to be elucidated, it is likely that through limiting excessive ROS levels, PO2 cycling initiates ROS-related antioxidant defenses.

  9. A free-piston Stirling cryocooler using metal diaphragms

    Science.gov (United States)

    Caughley, Alan; Sellier, Mathieu; Gschwendtner, Michael; Tucker, Alan

    2016-12-01

    A novel concept for a free-piston Stirling cryocooler has been proposed. The concept uses a pair of metal diaphragms to seal and suspend the displacer of a free-piston Stirling cryocooler. The diaphragms allow the displacer to move without rubbing or moving seals, potentially resulting in a long-life mechanism. When coupled to a metal diaphragm pressure wave generator, the system produces a complete Stirling cryocooler with no rubbing parts in the working gas space. Initial modelling of this concept using the Sage modelling tool indicates the potential for a useful cryocooler. A proof-of-concept prototype was constructed and achieved cryogenic temperatures. A second prototype was designed and constructed using the experience gained from the first. The prototype produced 29 W of cooling at 77 K and reached a no-load temperature of 56 K. Sage predicted the macroscopic behaviour of the prototype well but did not provide sufficient insights to improve performance significantly. This paper presents details of the development, modelling and testing of the proof-of-concept prototype and a second, improved prototype.

  10. Design-based modeling of magnetically actuated soft diaphragm materials

    Science.gov (United States)

    Jayaneththi, V. R.; Aw, K. C.; McDaid, A. J.

    2018-04-01

    Magnetic polymer composites (MPC) have shown promise for emerging biomedical applications such as lab-on-a-chip and implantable drug delivery. These soft material actuators are capable of fast response, large deformation and wireless actuation. Existing MPC modeling approaches are computationally expensive and unsuitable for rapid design prototyping and real-time control applications. This paper proposes a macro-scale 1-DOF model capable of predicting force and displacement of an MPC diaphragm actuator. Model validation confirmed both blocked force and displacement can be accurately predicted in a variety of working conditions i.e. different magnetic field strengths, static/dynamic fields, and gap distances. The contribution of this work includes a comprehensive experimental investigation of a macro-scale diaphragm actuator; the derivation and validation of a new phenomenological model to describe MPC actuation; and insights into the proposed model’s design-based functionality i.e. scalability and generalizability in terms of magnetic filler concentration and diaphragm diameter. Due to the lumped element modeling approach, the proposed model can also be adapted to alternative actuator configurations, and thus presents a useful tool for design, control and simulation of novel MPC applications.

  11. PO2 cycling reduces diaphragm fatigue by attenuating ROS formation.

    Directory of Open Access Journals (Sweden)

    Li Zuo

    Full Text Available Prolonged muscle exposure to low PO2 conditions may cause oxidative stress resulting in severe muscular injuries. We hypothesize that PO2 cycling preconditioning, which involves brief cycles of diaphragmatic muscle exposure to a low oxygen level (40 Torr followed by a high oxygen level (550 Torr, can reduce intracellular reactive oxygen species (ROS as well as attenuate muscle fatigue in mouse diaphragm under low PO2. Accordingly, dihydrofluorescein (a fluorescent probe was used to monitor muscular ROS production in real time with confocal microscopy during a lower PO2 condition. In the control group with no PO2 cycling, intracellular ROS formation did not appear during the first 15 min of the low PO2 period. However, after 20 min of low PO2, ROS levels increased significantly by ∼30% compared to baseline, and this increase continued until the end of the 30 min low PO2 condition. Conversely, muscles treated with PO2 cycling showed a complete absence of enhanced fluorescence emission throughout the entire low PO2 period. Furthermore, PO2 cycling-treated diaphragm exhibited increased fatigue resistance during prolonged low PO2 period compared to control. Thus, our data suggest that PO2 cycling mitigates diaphragm fatigue during prolonged low PO2. Although the exact mechanism for this protection remains to be elucidated, it is likely that through limiting excessive ROS levels, PO2 cycling initiates ROS-related antioxidant defenses.

  12. Influence of double-diaphragm vacuum compaction on deformation during forming of composite prepregs

    Directory of Open Access Journals (Sweden)

    Hassan Alshahrani

    2016-12-01

    Full Text Available During the diaphragm forming process, a vacuum seal is applied between the upper and lower diaphragms to compact and hold the laminate. Therefore, a thorough characterization of the in-plane shear behavior of fabrics under diaphragm forming conditions must take into account the effect of vacuum-sealing and compaction between the two diaphragms during bias extension. The study presented here examined the shear angles of out-of-autoclave 8-harness satin woven carbon/epoxy prepregs under diaphragm compaction. A bias extension test was conducted to study the effect of diaphragm compaction and ply interactions on shear properties. The test was performed at different compaction levels, and changes in shear angle with respect to vacuum levels and diaphragm compaction forces were observed. The contribution of diaphragm material and ply interaction to shear stiffness was evaluated and compared with results from a direct bias extension test. The samples were tested at both room temperature and at elevated temperatures using a radiant heater. The results show that shear angle decreases significantly as vacuum pressure and compaction is applied between the two diaphragms. This finding indicates that vacuum levels and compaction forces have a significant influence on the deformation limit and wrinkling onset during the diaphragm forming process.

  13. GND-PCA-based statistical modeling of diaphragm motion extracted from 4D MRI.

    Science.gov (United States)

    Swastika, Windra; Masuda, Yoshitada; Xu, Rui; Kido, Shoji; Chen, Yen-Wei; Haneishi, Hideaki

    2013-01-01

    We analyzed a statistical model of diaphragm motion using regular principal component analysis (PCA) and generalized N-dimensional PCA (GND-PCA). First, we generate 4D MRI of respiratory motion from 2D MRI using an intersection profile method. We then extract semiautomatically the diaphragm boundary from the 4D-MRI to get subject-specific diaphragm motion. In order to build a general statistical model of diaphragm motion, we normalize the diaphragm motion in time and spatial domains and evaluate the diaphragm motion model of 10 healthy subjects by applying regular PCA and GND-PCA. We also validate the results using the leave-one-out method. The results show that the first three principal components of regular PCA contain more than 98% of the total variation of diaphragm motion. However, validation using leave-one-out method gives up to 5.0 mm mean of error for right diaphragm motion and 3.8 mm mean of error for left diaphragm motion. Model analysis using GND-PCA provides about 1 mm margin of error and is able to reconstruct the diaphragm model by fewer samples.

  14. Progressive Diaphragm Atrophy in Pediatric Acute Respiratory Failure.

    Science.gov (United States)

    Glau, Christie L; Conlon, Thomas W; Himebauch, Adam S; Yehya, Nadir; Weiss, Scott L; Berg, Robert A; Nishisaki, Akira

    2018-02-05

    Diaphragm atrophy is associated with delayed weaning from mechanical ventilation and increased mortality in critically ill adults. We sought to test for the presence of diaphragm atrophy in children with acute respiratory failure. Prospective, observational study. Single-center tertiary noncardiac PICU in a children's hospital. Invasively ventilated children with acute respiratory failure. Diaphragm thickness at end-expiration and end-inspiration were serially measured by ultrasound in 56 patients (median age, 17 mo; interquartile range, 5.5-52), first within 36 hours of intubation and last preceding extubation. The median duration of mechanical ventilation was 140 hours (interquartile range, 83-201). At initial measurement, thickness at end-expiration was 2.0 mm (interquartile range, 1.8-2.5) and thickness at end-inspiration was 2.5 mm (interquartile range, 2-2.8). The change in thickness at end-expiration during mechanical ventilation between first and last measurement was -13.8% (interquartile range, -27.4% to 0%), with a -3.4% daily atrophy rate (interquartile range, -5.6 to 0%). Thickening fraction = ([thickness at end-inspiration - thickness at end-expiration]/thickness at end-inspiration) throughout the course of mechanical ventilation was linearly correlated with spontaneous breathing fraction (beta coefficient, 9.4; 95% CI, 4.2-14.7; p = 0.001). For children with a period of spontaneous breathing fraction less than 0.5 during mechanical ventilation, those with exposure to a continuous neuromuscular blockade infusion (n = 15) had a significantly larger decrease in thickness at end-expiration compared with children with low spontaneous breathing fraction who were not exposed to a neuromuscular blockade infusion (n = 18) (-16.4%, [interquartile range, -28.4% to -7.0%] vs -7.3%; [interquartile range, -10.9% to -0%]; p = 0.036). Diaphragm atrophy is present in children on mechanical ventilation for acute respiratory failure. Diaphragm contractility, measured as

  15. Proof mass effects on spiral electrode d33 mode piezoelectric diaphragm-based energy harvester

    KAUST Repository

    Shen, Zhiyuan; Liu, Shuwei; Miao, Jianmin; Woh, Lye Sun; Wang, Zhihong

    2013-01-01

    This paper presents the characterization of an energy harvester using a piezoelectric diaphragm as the vibration energy conversion microstructure. The diaphragm containing the spiral electrode operates in the d33 mode. The energy harvesting performance of the diaphragm was characterized. The optimal resistance load and the working frequency were characterized. The resonance tuning and the energy harvesting enhancement due to a proof mass were verified. © 2013 IEEE.

  16. A Study of Free-Piston Double-Diaphragm Drivers for Expansion Tubes. Report 1

    Science.gov (United States)

    Kendall, M. A.

    1997-01-01

    In recent years the free-piston double-diaphragm driver has been used to increase the performance of the XI pilot expansion tube to super-orbital test conditions. However, the actual performance of the double-diaphragm driver was found to be considerably less than ideal. An experimental study of the double-diaphragm driver was carried out on the XI facility over a range of conditions with the objective of determining the effect of. heat losses; and the non-ideal rupture of the 'light' secondary diaphragm on the driver performance. The disparity between the theoretical and measured performance envelope are highlighted. A viscous limit for the experiments vas established. Heat transfer behind the primary shock is shown to be the mechanism behind this limit Incident, reflected and transmitted shock trajectories for the secondary diaphragm were experimentally determined and compared with computed trajectories from a one-dimensional diaphragm inertia model. It was found that the diaphragm did influence the unsteady expansion. A good agreement between experimental and computed shock trajectories was obtained using a diaphragm inertia model assuming that the diaphragm mass became negligible 3 microns after shock impact.

  17. Large Epiphrenic Diverticulum with Perforation and Leakage below the Diaphragm

    DEFF Research Database (Denmark)

    Brønserud, Majken Munk; Brenøe, Anne-Sofie; Eckardt, Jens

    2015-01-01

    contrast revealed contrast leakage near the minor curvature of the stomach. The following esophagogastroduodenoscopy demonstrated a giant dilatation of the esophagus, as well as a second esophageal lumen originating 25 cm from the incisors. The “false” lumen of the esophagus was located parallel...... to esophagus, ending blindly in a perforation below the diaphragm. The clinical presentation and the patient’s age make it most likely, that it was a long epiphrenic diverticulum of pulsion type. The patient was treated conservatively, discharged after 10 days and has been followed in our outpatient clinic...... for 8 months, until he died of aggressive pulmonary cancer....

  18. Dynamic performance analysis of diaphragm coupling base on ABAQUS

    Directory of Open Access Journals (Sweden)

    You Wen

    2017-04-01

    Full Text Available Base on the diaphragm coupling of driving system of a rotation testing machine,FEA software ABAQUS is used to simulate the force which the coupling gets when it is working,to obtain the stress and stain during the coupling with axial misalignment and degree misalignment and to find where the maximal stress is as well as its distribution.Then the nature frequency of the coupling is calculated by use of finite element software and rotor dynamics and compared with the date of misalignment and maximum speed from the manufacture,which verifies the correctness of the model and the reliability of the calculation method.

  19. Examination of human diaphragms for trichinosis, Hiroshima and Nagasaki

    Energy Technology Data Exchange (ETDEWEB)

    Gould, S E; Ozaki, Hiroyuki; Kimura, Kazuo

    1961-11-30

    Trichinella spiralis has been found in three species of mammals born in Hokkaido so it possibly infects other species in Japan, including man. Although examination of human diaphragms in a small series of 149 autopsies in Hiroshima and 37 autopsies in Nagasaki (by digestion, compression, and microscopic sections) failed to reveal any instance of trichinous infection, it is felt that the existence or absence of human trichinosis inJapan can be determined only by examination covering a larger series of autopsies, and performed in various parts of the country. 6 references.

  20. Determination of ventilatory liver movement via radiographic evaluation of diaphragm position

    International Nuclear Information System (INIS)

    Balter, James M.; Dawson, Laura A.; Kazanjian, Sahira; McGinn, Cornelius; Brock, Kristy K.; Lawrence, Theodore; Haken, Randall ten

    2001-01-01

    Purpose: To determine the accuracy of estimation of liver movement inferred by observing diaphragm excursion on radiographic images. Methods and Materials: Eight patients with focal liver cancer had platinum embolization microcoils implanted in their livers during catheterization of the hepatic artery for delivery of regional chemotherapy. These patients underwent fluoroscopy, during which normal breathing movement was recorded on videotape. Movies of breathing movement were digitized, and the relative projected positions of the diaphragm and coils were recorded. For 6 patients, daily radiographs were also acquired during treatment. Retrospective measurements of coil position were taken after the diaphragm was aligned with the superior portion of the liver on digitally reconstructed radiographs. Results: Coil movement of 4.9 to 30.4 mm was observed during normal breathing. Diaphragm position tracked inferior-superior coil displacement accurately (population σ 1.04 mm) throughout the breathing cycle. The range of coil movement was predicted by the range of diaphragm movement with an accuracy of 2.09 mm (σ). The maximum error observed measuring coil movement using diaphragm position was 3.8 mm for a coil 9.8 cm inferior to the diaphragm. However, the distance of the coil from the top of the diaphragm did not correlate significantly with the error in predicting liver excursion. Analysis of daily radiographs showed that the error in predicting coil position using the diaphragm as an alignment landmark was 1.8 mm (σ) in the inferior-superior direction and 2.2 mm in the left-right direction, similar in magnitude to the inherent uncertainty in alignment. Conclusions: This study demonstrated that the range of ventilatory movement of different locations within the liver is predicted by diaphragm position to an accuracy that matches or exceeds existing systems for ventilatory tracking. This suggests that the diaphragm is an acceptable anatomic landmark for radiographic

  1. Experimental Characterization of Piezoelectric Radial Field Diaphragms for Fluidic Control

    Science.gov (United States)

    Bryant, R. G.; Kavli, S. E.; Thomas, R. A., Jr.; Darji, K. J.; Mossi, K. M.

    2004-01-01

    NASA has recently developed a new piezoelectric actuator, the Radial Field Diaphragm or RFD. This actuator uses a radially-directed electric field to generate concentric out-of-plane (Z-axis) motion that allows this packaged device to be used as a pump or valve diaphragm. In order to efficiently use this new active device, experimental determination of pressure, flow rate, mechanical work, power consumption and overall efficiency needs to be determined by actually building a pump. However, without an optimized pump design, it is difficult to assess the quality of the data, as these results are inherent to the actual pump. Hence, separate experiments must be conducted in order to generate independent results to help guide the design criteria and pump quality. This paper focuses on the experiments used to generate the RFD's operational parameters and then compares these results to the experimentally determined results of several types of ball pumps. Also discussed are how errors are inherently introduced into the experiments, the pump design, experimental hardware and their effects on the overall system efficiency.

  2. Scattering study at free air ionization chamber diaphragm

    International Nuclear Information System (INIS)

    Santos, Alexandre Lo Bianco dos

    2011-01-01

    The maim of this work consisted in the assessment of the correction factor for air kerma, due to scattered radiation in the diaphragm of the free-air ionization chamber model 481. LNMRl measurements were made to acquire x-ray spectra corresponding to the Qualities RQR-M, described in IEC 61627 standards (2005). These spectra were used as input data in the MC simulations. The operational range of energy spectra provide up to 35 keV. This energy range is typically used in diagnostic radiology, although there is not primary standard for air kerma. The determination of this factor is a fundamental process in the primary standardization of the air kerma. These factors were obtained by computer simulation using the Penelope code. The results are k RQR-M1 =0,9946, k RQR -M2 =0,9932, k RQR-M3 =0,9978 and k RQR-M4 =0,9885; with uncertainties of 0,007 and coverage factor equal to 2. lt can be concluded that, with respect to the diaphragm, the chamber can be used in the primary standard of air kerma. (author)

  3. The influence of tensile forces on the deflection of circular diaphragms in pressure sensors

    NARCIS (Netherlands)

    Voorthuyzen, J.A.; Bergveld, Piet

    1984-01-01

    It is known that the deflection of a diaphragm is determined by two mechanisms, bending moments or bending stress and tensile forces or membrane stress. Usually the influence of tensile forces is not taken into account when calculating the mechanical properties of thin diaphragms. Hence the

  4. Free radicals in hypoxic rat diaphragm contractility: no role for xanthine oxidase.

    NARCIS (Netherlands)

    Heunks, L.M.A.; Machiels, H.A.; Abreu, R.A. de; Zhu, X.; Heijden, E. van der; Dekhuijzen, P.N.R.

    2001-01-01

    Recent evidence indicates that hypoxia enhances the generation of oxidants. Little is known about the role of free radicals in contractility of the rat diaphragm during hypoxia. We hypothesized that antioxidants improve contractility of the hypoxic rat diaphragm and that xanthine oxidase (XO) is an

  5. Diffusivity measurements in some organic solvents by a gas-liquid diaphragm cell

    NARCIS (Netherlands)

    Littel, R.J.; Littel, R.J.; Versteeg, Geert; van Swaaij, Willibrordus Petrus Maria

    1992-01-01

    A diaphragm cell has been developed for the measurement of diffusion coefficients of gases In liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process Is followed by means of the gas pressure decrease which is recorded by means of a

  6. Diffusivity Measurements in Some Organic Solvents by a Gas-Liquid Diaphragm Cell

    NARCIS (Netherlands)

    Littel, Rob J.; Versteeg, Geert F.; Swaaij, Wim P.M. van

    1992-01-01

    A diaphragm cell has been developed for the measurement of diffusion coefficients of gases in liquids. The diaphragm cell is operated batchwise with respect to both gas and liquid phases, and the diffusion process is followed by means of the gas pressure decrease which is recorded by means of a

  7. Design of calandria-end shield support diaphragm of Narora Atomic Power Project

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S K; Nanda Kumar, S; Kakodkar, A

    1975-01-01

    The calandria-end shield diaphragm is one of the important components in Narora Atomic Power Plant. The support diaphragm is designed against elastic and plastic instability failures. Method of analysis for elastic and plastic instability is discussed for normal loading, pipe rupture loading, and earthquake loading.

  8. Design of calandria-end shield support diaphragm of Narora Atomic Power Project

    International Nuclear Information System (INIS)

    Srivastava, S.K.; Nanda Kumar, S.; Kakodkar, A.

    1975-01-01

    The calandria-end shield diaphragm is one of the important components in Narora Atomic Power Plant. The support diaphragm is designed against elastic and plastic instability failures. Method of analysis for elastic and plastic instability is discussed for normal loading, pipe rupture loading and earthquake loading. (author)

  9. The diaphragms of fenestrated endothelia: gatekeepers of vascular permeability and blood composition.

    Science.gov (United States)

    Stan, Radu V; Tse, Dan; Deharvengt, Sophie J; Smits, Nicole C; Xu, Yan; Luciano, Marcus R; McGarry, Caitlin L; Buitendijk, Maarten; Nemani, Krishnamurthy V; Elgueta, Raul; Kobayashi, Takashi; Shipman, Samantha L; Moodie, Karen L; Daghlian, Charles P; Ernst, Patricia A; Lee, Hong-Kee; Suriawinata, Arief A; Schned, Alan R; Longnecker, Daniel S; Fiering, Steven N; Noelle, Randolph J; Gimi, Barjor; Shworak, Nicholas W; Carrière, Catherine

    2012-12-11

    Fenestral and stomatal diaphragms are endothelial subcellular structures of unknown function that form on organelles implicated in vascular permeability: fenestrae, transendothelial channels, and caveolae. PV1 protein is required for diaphragm formation in vitro. Here, we report that deletion of the PV1-encoding Plvap gene in mice results in the absence of diaphragms and decreased survival. Loss of diaphragms did not affect the fenestrae and transendothelial channels formation but disrupted the barrier function of fenestrated capillaries, causing a major leak of plasma proteins. This disruption results in early death of animals due to severe noninflammatory protein-losing enteropathy. Deletion of PV1 in endothelium, but not in the hematopoietic compartment, recapitulates the phenotype of global PV1 deletion, whereas endothelial reconstitution of PV1 rescues the phenotype. Taken together, these data provide genetic evidence for the critical role of the diaphragms in fenestrated capillaries in the maintenance of blood composition. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Anatomic connections of the diaphragm influence of respiration on the body system

    Directory of Open Access Journals (Sweden)

    Bordoni B

    2013-07-01

    Full Text Available Bruno Bordoni,1 Emiliano Zanier2 1Rehabilitation Cardiology Institute of Hospitalization and Care with Scientific Address, S Maria Nascente Don Carlo Gnocchi Foundation, 2EdiAcademy, Milano, Italy Abstract: The article explains the scientific reasons for the diaphragm muscle being an important crossroads for information involving the entire body. The diaphragm muscle extends from the trigeminal system to the pelvic floor, passing from the thoracic diaphragm to the floor of the mouth. Like many structures in the human body, the diaphragm muscle has more than one function, and has links throughout the body, and provides the network necessary for breathing. To assess and treat this muscle effectively, it is necessary to be aware of its anatomic, fascial, and neurologic complexity in the control of breathing. The patient is never a symptom localized, but a system that adapts to a corporeal dysfunction. Keywords: diaphragm, fascia, phrenic nerve, vagus nerve, pelvis

  11. Fully automatic algorithm for segmenting full human diaphragm in non-contrast CT Images

    Science.gov (United States)

    Karami, Elham; Gaede, Stewart; Lee, Ting-Yim; Samani, Abbas

    2015-03-01

    The diaphragm is a sheet of muscle which separates the thorax from the abdomen and it acts as the most important muscle of the respiratory system. As such, an accurate segmentation of the diaphragm, not only provides key information for functional analysis of the respiratory system, but also can be used for locating other abdominal organs such as the liver. However, diaphragm segmentation is extremely challenging in non-contrast CT images due to the diaphragm's similar appearance to other abdominal organs. In this paper, we present a fully automatic algorithm for diaphragm segmentation in non-contrast CT images. The method is mainly based on a priori knowledge about the human diaphragm anatomy. The diaphragm domes are in contact with the lungs and the heart while its circumference runs along the lumbar vertebrae of the spine as well as the inferior border of the ribs and sternum. As such, the diaphragm can be delineated by segmentation of these organs followed by connecting relevant parts of their outline properly. More specifically, the bottom surface of the lungs and heart, the spine borders and the ribs are delineated, leading to a set of scattered points which represent the diaphragm's geometry. Next, a B-spline filter is used to find the smoothest surface which pass through these points. This algorithm was tested on a noncontrast CT image of a lung cancer patient. The results indicate that there is an average Hausdorff distance of 2.96 mm between the automatic and manually segmented diaphragms which implies a favourable accuracy.

  12. DOUBLE BOSS SCULPTURED DIAPHRAGM EMPLOYED PIEZORESISTIVE MEMS PRESSURE SENSOR WITH SILICON-ON-INSULATOR (SOI

    Directory of Open Access Journals (Sweden)

    D. SINDHANAISELVI

    2017-07-01

    Full Text Available This paper presents the detailed study on the measurement of low pressure sensor using double boss sculptured diaphragm of piezoresistive type with MEMS technology in flash flood level measurement. The MEMS based very thin diaphragms to sense the low pressure is analyzed by introducing supports to achieve linearity. The simulation results obtained from Intellisuite MEMS CAD design tool show that very thin diaphragms with rigid centre or boss give acceptable linearity. Further investigations on very thin diaphragms embedded with piezoresistor for low pressure measurement show that it is essential to analyse the piezoresistor placement and size of piezoresistor to achieve good sensitivity. A modified analytical modelling developed in this study for double boss sculptured diaphragm results were compared with simulated results. Further the enhancement of sensitivity is analyzed using non uniform thickness diaphragm and Silicon-On-Insulator (SOI technique. The simulation results indicate that the double boss square sculptured diaphragm with SOI layer using 0.85μm thickness yields the higher voltage sensitivity, acceptable linearity with Small Scale Deflection.

  13. Design of Diaphragm Based MEMS Pressure Sensor with Sensitivity Analysis for Environmental Applications

    Directory of Open Access Journals (Sweden)

    A. Nallathambi

    2015-05-01

    Full Text Available In this paper Micro-electromechanical System (MEMS diaphragm based pressure sensor for environmental applications is discussed. The main focus of this paper is to design, simulate and analyze the sensitivity of MEMS based diaphragm using different structures to measure the low and high pressure values. The simulation is done through the finite element tool and specifications related the maximum convinced stress; deflection and sensitivity of the diaphragms have been analyzed using the software INTELLISUITE 8.7v. The change in pressure is to bending of the diaphragm that modifies the measured displacement between the substrate and the diaphragm. This change in displacement gives the measure of the pressure in that environment. The design of these studies can be used to improve the sensitivity of these devices. Here the diaphragm based pressure sensor produced better displacement, sensitivity and stress output responses are obtained from the square diaphragm. The pressure range from 0.6 MPa to 25 MPa and its maximum displacement is accordingly 59 mm over a pressure range of 0 to 2 MPa. Its sensitivity is therefore 2.35 [10E-12/Pa].

  14. Convergence of pattern generator outputs on a common mechanism of diaphragm motor unit recruitment.

    Science.gov (United States)

    Mantilla, Carlos B; Seven, Yasin B; Sieck, Gary C

    2014-01-01

    Motor units are the final element of neuromotor control. In manner analogous to the organization of neuromotor control in other skeletal muscles, diaphragm motor units comprise phrenic motoneurons located in the cervical spinal cord that innervate the diaphragm muscle, the main inspiratory muscle in mammals. Diaphragm motor units play a primary role in sustaining ventilation but are also active in other nonventilatory behaviors, including coughing, sneezing, vomiting, defecation, and parturition. Diaphragm muscle fibers comprise all fiber types. Thus, diaphragm motor units display substantial differences in contractile and fatigue properties, but importantly, properties of the motoneuron and muscle fibers within a motor unit are matched. As in other skeletal muscles, diaphragm motor units are recruited in order such that motor units that display greater fatigue resistance are recruited earlier and more often than more fatigable motor units. The properties of the motor unit population are critical determinants of the function of a skeletal muscle across the range of possible motor tasks. Accordingly, fatigue-resistant motor units are sufficient to generate the forces necessary for ventilatory behaviors, whereas more fatigable units are only activated during expulsive behaviors important for airway clearance. Neuromotor control of diaphragm motor units may reflect selective inputs from distinct pattern generators distributed according to the motor unit properties necessary to accomplish these different motor tasks. In contrast, widely distributed inputs to phrenic motoneurons from various pattern generators (e.g., for breathing, coughing, or vocalization) would dictate recruitment order based on intrinsic electrophysiological properties. © 2014 Elsevier B.V. All rights reserved.

  15. Analytical investigation of bidirectional ductile diaphragms in multi-span bridges

    Science.gov (United States)

    Wei, Xiaone; Bruneau, Michel

    2018-04-01

    In the AASHTO Guide Specifications for Seismic Bridge Design Provisions, ductile diaphragms are identified as Permissible Earthquake-Resisting Elements (EREs), designed to help resist seismic loads applied in the transverse direction of bridges. When adding longitudinal ductile diaphragms, a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge's longitudinal and transverse axes. This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces (BRBs) in straight multi-span bridge with simply supported floating spans. The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered. Design procedures for the bidirectional ductile diaphragms are first proposed. An analytical model of the example bridge with bidirectional ductile diaphragms, designed based on the proposed methodology, is then built in SAP2000. Pushover and nonlinear time history analyses are performed on the bridge model, and corresponding results are presented. The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated, in order to better understand the impact on the bridge's dynamic performance.

  16. First reported experience with intramuscular diaphragm pacing in replacing positive pressure mechanical ventilators in children.

    Science.gov (United States)

    Onders, Raymond P; Ponsky, Todd A; Elmo, MaryJo; Lidsky, Karen; Barksdale, Edward

    2011-01-01

    Diaphragm pacing (DP) has been shown to successfully replace mechanical ventilators for adult tetraplegic patients with chronic respiratory insufficiency. This is the first report of DP in ventilator-dependent children. This was a prospective interventional experience under institutional review board approval. Diaphragm pacing involves outpatient laparoscopic diaphragm motor point mapping to identify the site where stimulation causes maximum diaphragm contraction with implantation of 4 percutaneous intramuscular electrodes. Diaphragm conditioning ensues to wean the child from the ventilator. Six children were successfully implanted ranging from 5 to 17 years old with the smallest 15 kg in weight. Length of time on mechanical ventilation ranged from 11 days to 7.6 years with an average of 3.2 years. In all patients, DP provided tidal volumes above basal needs. Five of the patients underwent a home-based weaning program, whereas one patient who was implanted only 11 days post spinal cord injury never returned to the ventilator with DP use. Another patient was weaned from the ventilator full time but died of complications of his underlying brain stem tumor. The remaining patients weaned from the ventilator for over 14 hours a day and/or are actively conditioning their diaphragms. Diaphragm pacing successfully replaced mechanical ventilators, which improves quality of life. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Investigation of the Durability of a Diaphragm for a Total Artificial Heart.

    Science.gov (United States)

    Gräf, Felix; Rossbroich, Ralf; Finocchiaro, Thomas; Steinseifer, Ulrich

    2016-10-01

    One of the most critical components regarding the durability of the ReinHeart total artificial heart (TAH) is its biocompatible diaphragm, which separates the drive unit from the ventricles. Hence, a durability tester was designed to investigate its required 5-year lifetime. The aim of this study was to prove the validity of accelerated testing of the polyurethane diaphragm. The durability tester allows simultaneous testing of 12 diaphragms and mimics physiological conditions. To accelerate the time of testing, it operates with an increased speed at a frequency of 8 Hz. To prove the correctness of this acceleration, a servo-hydraulic testing machine was used to study the effect of different frequencies and their corresponding loads. Thereby the viscoelastic behavior of the polyurethane was investigated. Additionally, high-speed video measurements were performed. The force against frequency and the high-speed video measurements showed constant behavior. In the range of 1-10 Hz, the maximum resulting forces varied by 3%, and the diaphragm movement was identical. Frequencies below 10 Hz allow a valid statement of the diaphragm's mechanical durability. Viscoelasticity of the polyurethane in the considered frequency-range is negligible. The accelerated durability test is applicable to polyurethane diaphragms, and the results are applicable to TAH use. The reliability of the diaphragm for a lifetime of 5 years was found to be 80% with a confidence of 62%. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  18. Method of production of a diaphragm for instruments in particle optics and diaphragm fabricated by this method

    International Nuclear Information System (INIS)

    Sandrik, J.; Krohne, P.

    1975-01-01

    The production method of, e.g., a circular diaphragm for an electron microscope is based on copper plate as supporting material. A light-sensitive, electrically insulating layer is coated on this. After exposing and freeing the positions of this layer, e.g., the circular interior as well as the cross-piece to the exterior of the diaghragm, a galvanic building-up of a noble metal layer follows, e.g. gold, on these now free positions. After freeing the remaining non-exposed material, an etching-protective lacquer is coated on the positions of the supporting material which are to be maintained. The remaining parts of the supporting material are then removed by positive etching. (DG/LH) [de

  19. Quantification of Diaphragm Mechanics in Pompe Disease Using Dynamic 3D MRI.

    Directory of Open Access Journals (Sweden)

    Katja Mogalle

    Full Text Available Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respiratory muscle involvement is necessary to initiate treatment in time and possibly prevent irreversible damage. In this paper we investigate the suitability of dynamic MR imaging in combination with state-of-the-art image analysis methods to assess respiratory muscle weakness.The proposed methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle.Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function tests. Pompe patients with severely reduced pulmonary function showed severe diaphragm weakness presented by minimal motion of the diaphragm. In patients with moderately reduced pulmonary function, cranial displacement of posterior diaphragm parts was reduced and the diaphragm dome was oriented more horizontally at full inspiration compared to healthy controls.Dynamic 3D MRI provides data for analyzing the contribution of both diaphragm and thoracic muscles independently. The proposed image analysis method has the potential to detect less severe diaphragm weakness and could thus be used to determine the optimal start of treatment in adult patients with Pompe disease in prospect of increased treatment response.

  20. Effect of Elastase-induced Emphysema on the Force-generating Ability of the Diaphragm

    Science.gov (United States)

    Supinski, Gerald S.; Kelsen, Steven G.

    1982-01-01

    The effect of emphysema on the ability of the diaphragm to generate force was examined in costal diaphragm muscle strips from 10 Golden hamsters killed 18 mo after intratracheal injection of pancreatic elastase in a dose producing hyperinflation (mean total lung capacity [TLC] = 163% of control) and generalized panacinar emphysema. 13 saline-injected normal animals served as controls. The time course of isometric tension and the effect of alterations in muscle fiber and sarcomere length on the isometric tension (T) generated in response to tetanizing electrical stimuli (length-tension [L-T] relationship) were examined. Elastase administration caused an increase in diaphragm muscle thickness and reduction in the length of costal diaphragm muscle fibers measured in situ. Emphysema significantly increased the maximum tetanic tension as a result of hypertrophy. Maximal tension corrected for increases in muscle cross-sectional area (T/cm2), however, was the same in emphysematous (E) and control (C) animals. Emphysema also shifted the muscle fiber L-T curve of the diaphragm but not of a control muscle, the soleus, toward shorter lengths. In contrast to the effects of E on the diaphragm muscle fiber L-T curve, the sarcomere L-T curve was the same in E and C. Since the length at which tension was maximal correlated closely with sarcomere number (r = 0.94; P < 0.001) reduction in the number of sarcomeres in series in muscles from emphysematous animals appeared to explain the shift in the muscle fiber L-T curve. We conclude that in elastase-induced emphysema adaptive changes both in diaphragm cross-sectional area and sarcomere number augment the force-generating ability of the diaphragm. We speculate that changes in sarcomere number compensate for alterations in muscle fiber length resulting from chronic hyperinflation of the thorax, while diaphragmatic muscle hypertrophy represents a response to changes in respiratory load and/or diaphragm configuration (La

  1. Cough induced rib fracture, rupture of the diaphragm and abdominal herniation

    Directory of Open Access Journals (Sweden)

    Wurl Peter

    2006-11-01

    Full Text Available Abstract Cough can be associated with many complications. In this article, we present a 59 year old male patient with a very rare combination of a cough related stress fracture of the ninth rib, a traumatic rupture of the diaphragm, and an abdominal wall herniation. The hernia was repaired through surgical treatment without bowel resection, the diaphragm and the internal and oblique abdominal muscle were adapted, and the abdomen was reinforced with a prolene net. Although each individual injury is well documented in the literature, the combination of rib fracture, abdominal herniation and diaphragm rupture has not been reported.

  2. Internally-cooled centrifugal compressor with cooling jacket formed in the diaphragm

    Science.gov (United States)

    Moore, James J.; Lerche, Andrew H.; Moreland, Brian S.

    2014-08-26

    An internally-cooled centrifugal compressor having a shaped casing and a diaphragm disposed within the shaped casing having a gas side and a coolant side so that heat from a gas flowing though the gas side is extracted via the coolant side. An impeller disposed within the diaphragm has a stage inlet on one side and a stage outlet for delivering a pressurized gas to a downstream connection. The coolant side of the diaphragm includes at least one passageway for directing a coolant in a substantially counter-flow direction from the flow of gas through the gas side.

  3. Diaphragm Muscle Weakness Following Acute Sustained Hypoxic Stress in the Mouse Is Prevented by Pretreatment with N-Acetyl Cysteine

    Directory of Open Access Journals (Sweden)

    Andrew J. O’Leary

    2018-01-01

    Full Text Available Oxygen deficit (hypoxia is a major feature of cardiorespiratory diseases characterized by diaphragm dysfunction, yet the putative role of hypoxic stress as a driver of diaphragm dysfunction is understudied. We explored the cellular and functional consequences of sustained hypoxic stress in a mouse model. Adult male mice were exposed to 8 hours of normoxia, or hypoxia (FiO2 = 0.10 with or without antioxidant pretreatment (N-acetyl cysteine, 200 mg/kg i.p.. Ventilation and metabolism were measured. Diaphragm muscle contractile function, myofibre size and distribution, gene expression, protein signalling cascades, and oxidative stress (TBARS were determined. Hypoxia caused pronounced diaphragm muscle weakness, unrelated to increased respiratory muscle work. Hypoxia increased diaphragm HIF-1α protein content and activated MAPK, mTOR, Akt, and FoxO3a signalling pathways, largely favouring protein synthesis. Hypoxia increased diaphragm lipid peroxidation, indicative of oxidative stress. FoxO3 and MuRF-1 gene expression were increased. Diaphragm 20S proteasome activity and muscle fibre size and distribution were unaffected by acute hypoxia. Pretreatment with N-acetyl cysteine substantially enhanced cell survival signalling, prevented hypoxia-induced diaphragm oxidative stress, and prevented hypoxia-induced diaphragm dysfunction. Hypoxia is a potent driver of diaphragm weakness, causing myofibre dysfunction without attendant atrophy. N-acetyl cysteine protects the hypoxic diaphragm and may have application as a potential adjunctive therapy.

  4. Diaphragm flange and method for lowering particle beam impedance at connected beam tubes of a particle accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Biallas, George Herman

    2017-07-04

    A diaphragm flange for connecting the tubes in a particle accelerator while minimizing beamline impedance. The diaphragm flange includes an outer flange and a thin diaphragm integral with the outer flange. Bolt holes in the outer flange provide a means for bolting the diaphragm flange to an adjacent flange or beam tube having a mating bolt-hole pattern. The diaphragm flange includes a first surface for connection to the tube of a particle accelerator beamline and a second surface for connection to a CF flange. The second surface includes a recessed surface therein and a knife-edge on the recessed surface. The diaphragm includes a thickness that enables flexing of the integral diaphragm during assembly of beamline components. The knife-edge enables compression of a soft metal gasket to provide a leak-tight seal.

  5. Investigation into the behaviour of concrete anchored diaphragm walls under earthquake condition

    International Nuclear Information System (INIS)

    Saba, H. R.; Rahaii, A. R.

    2003-01-01

    Diaphragm walls are frequently used in civil Engineering projects. Considering the variety and important volume of consumed materials (concrete, anchors and soil), one of the important factors for design and construction of these walls, are their behaviour under different executive, and loading conditions. In this paper, various models of concrete diaphragms with different number of anchors and soil parameters under static and dynamic loading have been investigated using finite element method with nonlinear models. Results including the internal forces in diaphragm walls, variation of forces in the anchors, shape of the sliding surface and variation of pressure in soil are obtained and compared. An experimental tool with suitable measurement systems for determining the pressure and internal forces was designed and realised. Also with similitude and dimensional analyses, diaphragms with different number of anchors were built and set on the shaking table test and experimented under different accelograms. Finally results of nonlinear dynamic analysis were compared with experimental results

  6. Development of a Hemispherical Metal Diaphragm for Single-Cycle Liquid-Metal Positive Expulsion Systems

    National Research Council Canada - National Science Library

    Gorland, Sol

    1965-01-01

    This report presents experimental results pertaining to the design and development of a metallic expulsion diaphragm for single-cycle positive expulsion of high-temperature liquid in an agravity condition...

  7. Documentation of diaphragmal paralysis with digital subtraction techniques. Dokumentation von Zwerchfellparesen mit digitaler Subtraktionstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Waggershauser, T. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Buente, E. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Kohz, P. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke); Fink, U. (Muenchen Univ. (Germany). Radiologische Klinik und Poliklinik Muenchen Univ. (Germany). Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenkranke)

    1992-01-01

    The causative factors for a paresis of the diaphragm are primarily subsequent to operations on lesions of the phrenic nerve or on such mediastinal tumors as lyphomas which result in compression or infiltration of the nerves. (orig.)

  8. Computer simulation analysis of normal and abnormal development of the mammalian diaphragm

    Directory of Open Access Journals (Sweden)

    Bodenstein Lawrence

    2006-02-01

    Full Text Available Abstract Background Congenital diaphragmatic hernia (CDH is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF, esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++™ to study diaphragm morphogenesis. Methods and results Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++™ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1 cell mitoses are restricted to the edge of growing tissue; (2 cells near the chest wall remain mitotically active; (3 mitotically active non-edge cells migrate toward the chest wall; and (4 movement direction depends on clonal differentiation between anterior and posterior PPF cells. Conclusion With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to

  9. Computer simulation analysis of normal and abnormal development of the mammalian diaphragm

    Science.gov (United States)

    Fisher, Jason C; Bodenstein, Lawrence

    2006-01-01

    Background Congenital diaphragmatic hernia (CDH) is a birth defect with significant morbidity and mortality. Knowledge of diaphragm morphogenesis and the aberrations leading to CDH is limited. Although classical embryologists described the diaphragm as arising from the septum transversum, pleuroperitoneal folds (PPF), esophageal mesentery and body wall, animal studies suggest that the PPF is the major, if not sole, contributor to the muscular diaphragm. Recently, a posterior defect in the PPF has been identified when the teratogen nitrofen is used to induce CDH in fetal rodents. We describe use of a cell-based computer modeling system (Nudge++™) to study diaphragm morphogenesis. Methods and results Key diaphragmatic structures were digitized from transverse serial sections of paraffin-embedded mouse embryos at embryonic days 11.5 and 13. Structure boundaries and simulated cells were combined in the Nudge++™ software. Model cells were assigned putative behavioral programs, and these programs were progressively modified to produce a diaphragm consistent with the observed anatomy in rodents. Homology between our model and recent anatomical observations occurred under the following simulation conditions: (1) cell mitoses are restricted to the edge of growing tissue; (2) cells near the chest wall remain mitotically active; (3) mitotically active non-edge cells migrate toward the chest wall; and (4) movement direction depends on clonal differentiation between anterior and posterior PPF cells. Conclusion With the PPF as the sole source of mitotic cells, an early defect in the PPF evolves into a posteromedial diaphragm defect, similar to that of the rodent nitrofen CDH model. A posterolateral defect, as occurs in human CDH, would be more readily recreated by invoking other cellular contributions. Our results suggest that recent reports of PPF-dominated diaphragm morphogenesis in the rodent may not be strictly applicable to man. The ability to recreate a CDH defect

  10. Reinforcement of the pelvic diaphragm using a purse-string suture in dogs: description of technique

    Directory of Open Access Journals (Sweden)

    P.C. Moraes

    Full Text Available ABSTRACT Recurrence of perineal hernias is frequent, and is associated to poor identification of anatomical structures during surgery, inadequate suture placement, and failure of physical support of the pelvic diaphragm after surgical reconstruction. The objective of this work is to describe a novel surgical technique for reinforcement of the pelvic diaphragm after performing the internal obturator transposition technique in dogs with perineal hernia.

  11. Study on the onset of DC diaphragm glow discharge

    International Nuclear Information System (INIS)

    Jin, Xinglong; Wang, Xiaoyan; Zhang, Hongmei; Ren, Hongxia

    2013-01-01

    In this paper, the DC diaphragm glow discharge (DGD) occurred around the small hole on quartz tube between two submersed graphite electrodes and the onset of DGD was systematically investigated. It was found that critical voltage (V D ) decreased with the increasing conductivity, and then maintained at about 620 V. When the hole diameter increased from 1.0 mm to 2.5 mm, H 2 O 2 formation and AO discoloration in anolyte increased with the increase of the hole diameter. In addition, the effect of electrolyte constituents on H 2 O 2 formation and AO discoloration in anolyte induced by DGD was also studied. The concentration of H 2 O 2 and AO discoloration in anolyte was close in inert electrolyte such as Na 2 SO 4 and Na 2 HPO 4 solution. The concentration of H 2 O 2 and AO discoloration rate in Na 2 CO 3 and NaAc solution was lower than those in Na 2 SO 4 and Na 2 HPO 4 solution, due to their capture ability for ·OH. However, NaCl showed enhancing effect on AO discoloration, although it consumed a certain amount of H 2 O 2 . The energy efficiencies of AO discoloration and H 2 O 2 formation were also compared with those of other DGD reactor.

  12. Numerical investigation on vibration characteristics of a micro-speaker diaphragm considering thermoforming effects

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyeong Min; Park, Ke Un [Seoul National University of Science and Technology, Seoul (Korea, Republic of)

    2013-10-15

    Micro-speaker diaphragms play an important role in generating desired sound responses, and are designed to have thin membrane shapes for flexibility in the axial direction. The micro-speaker diaphragms are formed from thin polymer film through the thermoforming process, in which local thickness reductions occur due to strain localization. This thickness reduction results in a change in vibration characteristics of the diaphragm and different sound responses from that of the original design. In this study, the effect of this thickness change in the diaphragm on its vibration characteristics is numerically investigated by coupling thermoforming simulation, structural analysis and modal analysis. Thus, the thickness change in the diaphragm is calculated from the thermoforming simulation, and reflected in the further structural and modal analyses in order to estimate the relevant stiffness and vibration modes. Comparing these simulation results with those from a diaphragm with the uniform thickness, it is found that a local thickness reduction results in the stiffness reduction and the relevant change in the natural frequencies and the corresponding vibration modes.

  13. Numerical investigation on vibration characteristics of a micro-speaker diaphragm considering thermoforming effects

    International Nuclear Information System (INIS)

    Kim, Kyeong Min; Park, Ke Un

    2013-01-01

    Micro-speaker diaphragms play an important role in generating desired sound responses, and are designed to have thin membrane shapes for flexibility in the axial direction. The micro-speaker diaphragms are formed from thin polymer film through the thermoforming process, in which local thickness reductions occur due to strain localization. This thickness reduction results in a change in vibration characteristics of the diaphragm and different sound responses from that of the original design. In this study, the effect of this thickness change in the diaphragm on its vibration characteristics is numerically investigated by coupling thermoforming simulation, structural analysis and modal analysis. Thus, the thickness change in the diaphragm is calculated from the thermoforming simulation, and reflected in the further structural and modal analyses in order to estimate the relevant stiffness and vibration modes. Comparing these simulation results with those from a diaphragm with the uniform thickness, it is found that a local thickness reduction results in the stiffness reduction and the relevant change in the natural frequencies and the corresponding vibration modes.

  14. Measurement of thermal expansion coefficient of graphene diaphragm using optical fiber Fabry–Perot interference

    International Nuclear Information System (INIS)

    Li, Cheng; Liu, Qianwen; Peng, Xiaobin; Fan, Shangchun

    2016-01-01

    Application of the Fabry–Perot (FP) interference method for determining the coefficient of thermal expansion (CTE) of a graphene diaphragm is investigated in this paper. A miniature extrinsic FP interferometric (EFPI) sensor was fabricated by using an approximate 8-layer graphene diaphragm. The extremely thin diaphragm was transferred onto the endface of a ferrule with an inner diameter of 125 μ m, and van der Waals interactions between the graphene diaphragm and its substrate created a low finesse FP interferometer with a cavity length of 36.13 μ m. Double reference FP cavities using two cleaved optical fibers as reflectors were also constructed to differentially cancel the thermal expansion effects of the trapped gas and adhesive material. A temperature test demonstrated an approximate cavity length change of 166.1 nm °C −1 caused by film thermal expansion in the range of 20–60 °C. Then along with the established thermal deformation model of the suspended circular diaphragm, the calculated CTE ranging from  −9.98  ×  10 −6 K −1 to  −2.09  ×  10 −6 K −1 conformed well to the previously measured results. The proposed method would be applicable in other types of elastic materials as the sensitive diaphragm of an EFPI sensor over a wide temperature range. (paper)

  15. High-intensity interval training prevents oxidant-mediated diaphragm muscle weakness in hypertensive mice.

    Science.gov (United States)

    Bowen, T Scott; Eisenkolb, Sophia; Drobner, Juliane; Fischer, Tina; Werner, Sarah; Linke, Axel; Mangner, Norman; Schuler, Gerhard; Adams, Volker

    2017-01-01

    Hypertension is a key risk factor for heart failure, with the latter characterized by diaphragm muscle weakness that is mediated in part by increased oxidative stress. In the present study, we used a deoxycorticosterone acetate (DOCA)-salt mouse model to determine whether hypertension could independently induce diaphragm dysfunction and further investigated the effects of high-intensity interval training (HIIT). Sham-treated (n = 11), DOCA-salt-treated (n = 11), and DOCA-salt+HIIT-treated (n = 15) mice were studied over 4 wk. Diaphragm contractile function, protein expression, enzyme activity, and fiber cross-sectional area and type were subsequently determined. Elevated blood pressure confirmed hypertension in DOCA-salt mice independent of HIIT (P HIIT. Myosin heavy chain (MyHC) protein expression tended to decrease (∼30%; P = 0.06) in DOCA-salt vs. sham- and DOCA-salt+HIIT mice, whereas oxidative stress increased (P HIIT further prevented direct oxidant-mediated diaphragm contractile dysfunction (P hypertension induces diaphragm contractile dysfunction via an oxidant-mediated mechanism that is prevented by HIIT.-Bowen, T. S., Eisenkolb, S., Drobner, J., Fischer, T., Werner, S., Linke, A., Mangner, N., Schuler, G., Adams, V. High-intensity interval training prevents oxidant-mediated diaphragm muscle weakness in hypertensive mice. © FASEB.

  16. A modified SILCS contraceptive diaphragm for long-term controlled release of the HIV microbicide dapivirine.

    Science.gov (United States)

    Major, Ian; Boyd, Peter; Kilbourne-Brook, Maggie; Saxon, Gene; Cohen, Jessica; Malcolm, R Karl

    2013-07-01

    There is considerable interest in developing new multipurpose prevention technologies to address women's reproductive health needs. This study describes an innovative barrier contraceptive device--based on the SILCS diaphragm--that also provides long-term controlled release of the lead candidate anti-HIV microbicide dapivirine. Diaphragm devices comprising various dapivirine-loaded polymer spring cores overmolded with a nonmedicated silicone elastomer sheath were fabricated by injection molding processes. In vitro release testing, thermal analysis and mechanical characterization were performed on the devices. A diaphragm device containing a polyoxymethylene spring core loaded with 10% w/w dapivirine provided continuous and controlled release of dapivirine over a 6-month period, with a mean in vitro daily release rate of 174 mcg/day. The mechanical properties of the new diaphragm were closely matched to the SILCS diaphragm. The study demonstrates proof of concept for a dapivirine-releasing diaphragm with daily release quantities potentially capable of preventing HIV transmission. In discontinuous clinical use, release of dapivirine may be readily extended over 1 or more years. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. β-hydroxy-β-methylbutyrate (HMB) prevents sepsis-induced diaphragm dysfunction in mice.

    Science.gov (United States)

    Supinski, Gerald S; Callahan, Leigh A

    2014-06-01

    Infections induce severe respiratory muscle weakness. Currently there are no treatments for this important clinical problem. We tested the hypothesis that β-hydroxy-β-methylbutyrate (HMB) would prevent sepsis-induced diaphragm weakness. Four groups of adult male mice were studied: controls (saline-injected), sepsis (intraperitoneal lipopolysaccharide), sepsis+HMB (injected intravenously), and HMB. Diaphragm force generation and indices of caspase 3, calpain, 20S proteasomal subunit, and double-stranded RNA-dependent protein kinase (PKR) activation were assessed after 24h. Sepsis elicited large reductions in diaphragm specific force generation at all stimulation frequencies. Endotoxin also activated caspase 3, calpain, the 20S proteasomal subunit and PKR in the diaphragm. HMB blocked sepsis-induced caspase 3, 20S proteasomal and PKR activation, but did not prevent calpain activation. Most importantly, HMB administration significantly attenuated sepsis-induced diaphragm weakness, preserving muscle force generation at all stimulation frequencies (pHMB may prove to be an important therapy in infected patients, with the potential to increase diaphragm strength, to reduce the duration of mechanical ventilation and to decrease mortality in this patient population. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Quantifying the predictability of diaphragm motion during respiration with a noninvasive external marker

    International Nuclear Information System (INIS)

    Vedam, S.S.; Kini, V.R.; Keall, P.J.; Ramakrishnan, V.; Mostafavi, H.; Mohan, R.

    2003-01-01

    The aim of this work was to quantify the ability to predict intrafraction diaphragm motion from an external respiration signal during a course of radiotherapy. The data obtained included diaphragm motion traces from 63 fluoroscopic lung procedures for 5 patients, acquired simultaneously with respiratory motion signals (an infrared camera-based system was used to track abdominal wall motion). During these sessions, the patients were asked to breathe either (i) without instruction, (ii) with audio prompting, or (iii) using visual feedback. A statistical general linear model was formulated to describe the relationship between the respiration signal and diaphragm motion over all sessions and for all breathing training types. The model parameters derived from the first session for each patient were then used to predict the diaphragm motion for subsequent sessions based on the respiration signal. Quantification of the difference between the predicted and actual motion during each session determined our ability to predict diaphragm motion during a course of radiotherapy. This measure of diaphragm motion was also used to estimate clinical target volume (CTV) to planning target volume (PTV) margins for conventional, gated, and proposed four-dimensional (4D) radiotherapy. Results from statistical analysis indicated a strong linear relationship between the respiration signal and diaphragm motion (p<0.001) over all sessions, irrespective of session number (p=0.98) and breathing training type (p=0.19). Using model parameters obtained from the first session, diaphragm motion was predicted in subsequent sessions to within 0.1 cm (1 σ) for gated and 4D radiotherapy. Assuming a 0.4 cm setup error, superior-inferior CTV-PTV margins of 1.1 cm for conventional radiotherapy could be reduced to 0.8 cm for gated and 4D radiotherapy. The diaphragm motion is strongly correlated with the respiration signal obtained from the abdominal wall. This correlation can be used to predict diaphragm

  19. Diaphragm-Sparing Nerve Blocks for Shoulder Surgery.

    Science.gov (United States)

    Tran, De Q H; Elgueta, Maria Francisca; Aliste, Julian; Finlayson, Roderick J

    Shoulder surgery can result in significant postoperative pain. Interscalene brachial plexus blocks (ISBs) constitute the current criterion standard for analgesia but may be contraindicated in patients with pulmonary pathology due to the inherent risk of phrenic nerve block and symptomatic hemidiaphragmatic paralysis. Although ultrasound-guided ISB with small volumes (5 mL), dilute local anesthetic (LA) concentrations, and LA injection 4 mm lateral to the brachial plexus have been shown to reduce the risk of phrenic nerve block, no single intervention can decrease its incidence below 20%. Ultrasound-guided supraclavicular blocks with LA injection posterolateral to the brachial plexus may anesthetize the shoulder without incidental diaphragmatic dysfunction, but further confirmatory trials are required. Ultrasound-guided C7 root blocks also seem to offer an attractive, diaphragm-sparing alternative to ISB. However, additional large-scale studies are needed to confirm their efficacy and to quantify the risk of periforaminal vascular breach. Combined axillary-suprascapular nerve blocks may provide adequate postoperative analgesia for minor shoulder surgery but do not compare favorably to ISB for major surgical procedures. One intriguing solution lies in the combined use of infraclavicular brachial plexus blocks and suprascapular nerve blocks. Theoretically, the infraclavicular approach targets the posterior and lateral cords, thus anesthetizing the axillary nerve (which supplies the anterior and posterior shoulder joint), as well as the subscapular and lateral pectoral nerves (both of which supply the anterior shoulder joint), whereas the suprascapular nerve block anesthetizes the posterior shoulder. Future randomized trials are required to validate the efficacy of combined infraclavicular-suprascapular blocks for shoulder surgery.

  20. Displacement and resonance behaviors of a piezoelectric diaphragm driven by a double-sided spiral electrode

    KAUST Repository

    Shen, Zhiyuan

    2012-04-03

    This paper presents the design of a lead zirconate titanate (PZT) diaphragm actuated by double-sided patterned electrodes. Au/Cr electrodes were deposited on bulk PZT wafers by sputtering while patterned by a lift-off process. SU-8 thick film was used to form the structural layer. Double-spiral electrode induced in-plane poling and piezoelectric elongation are converted to an out-of-plane displacement due to the confined boundary condition. The influence of different drive configurations and electrode parameters on deflection has been calculated by finite element methods (FEM) using a uniform field model. Impedance and quasi-static displacement spectra of the diaphragm were measured after poling. Adouble-sided patterned electrode diaphragm can be actuated by more drive configurations than a single-sided one. Compared with a single-sided electrode drive, a double-sided out-of-phase drive configuration increases the coupling coefficient of the fundamental resonance from 7.6% to 11.8%. The displacement response of the diaphragm increases from 2.6 to 8.6nmV 1. Configurations including the electric field component perpendicular to the poling direction can stimulate shear modes of the diaphragm. © 2012 IOP Publishing Ltd.

  1. The role of Sema3–Npn-1 signaling during diaphragm innervation and muscle development

    Science.gov (United States)

    Huettl, Rosa-Eva; Hanuschick, Philipp; Amend, Anna-Lena; Alberton, Paolo; Aszodi, Attila; Huber, Andrea B.

    2016-01-01

    ABSTRACT Correct innervation of the main respiratory muscle in mammals, namely the thoracic diaphragm, is a crucial pre-requisite for the functionality of this muscle and the viability of the entire organism. Systemic impairment of Sema3A–Npn-1 (Npn-1 is also known as NRP1) signaling causes excessive branching of phrenic nerves in the diaphragm and into the central tendon region, where the majority of misguided axons innervate ectopic musculature. To elucidate whether these ectopic muscles are a result of misguidance of myoblast precursors due to the loss of Sema3A–Npn-1 signaling, we conditionally ablated Npn-1 in somatic motor neurons, which led to a similar phenotype of phrenic nerve defasciculation and, intriguingly, also formation of innervated ectopic muscles. We therefore hypothesize that ectopic myocyte fusion is caused by additional factors released by misprojecting growth cones. Slit2 and its Robo receptors are expressed by phrenic motor axons and migrating myoblasts, respectively, during innervation of the diaphragm. In vitro analyses revealed a chemoattractant effect of Slit2 on primary diaphragm myoblasts. Thus, we postulate that factors released by motor neuron growth cones have an influence on the migration properties of myoblasts during establishment of the diaphragm. PMID:27466379

  2. Assessing breathing motion by shape matching of lung and diaphragm surfaces

    Science.gov (United States)

    Urschler, Martin; Bischof, Horst

    2005-04-01

    Studying complex thorax breating motion is an important research topic for accurate fusion of functional and anatomical data, radiotherapy planning or reduction of breathing motion artifacts. We investigate segmented CT lung, airway and diaphragm surfaces at several different breathing states between Functional Residual and Total Lung Capacity. In general, it is hard to robustly derive corresponding shape features like curvature maxima from lung and diaphragm surfaces since diaphragm and rib cage muscles tend to deform the elastic lung tissue such that e.g. ridges might disappear. A novel registration method based on the shape context approach for shape matching is presented where we extend shape context to 3D surfaces. The shape context approach was reported as a promising method for matching 2D shapes without relying on extracted shape features. We use the point correspondences for a non-rigid thin-plate-spline registration to get deformation fields that describe the movement of lung and diaphragm. Our validation consists of experiments on phantom and real sheep thorax data sets. Phantom experiments make use of shapes that are manipulated with known transformations that simulate breathing behaviour. Real thorax data experiments use a data set showing lungs and diaphragm at 5 distinct breathing states, where we compare subsets of the data sets and qualitatively and quantitatively asses the registration performance by using manually identified corresponding landmarks.

  3. D33 mode piezoelectric diaphragm based acoustic transducer with high sensitivity

    KAUST Repository

    Shen, Zhiyuan; Lu, Jingyu; Tan, Cheewee; Miao, Jianmin; Wang, Zhihong

    2013-01-01

    This paper presents the design, fabrication, and characterization of an acoustic transducer using a piezoelectric freestanding bulk diaphragm as the sensing element. The diaphragm bearing the spiral electrode operates in d 33 mode, which allows the in-plane deformation of the diaphragm to be converted to the out-of-plane deformation and generates an acoustic wave in the same direction. A finite element code is developed to reorient the material polarization distribution according to the poling field calculated. The first four resonance modes have been simulated and verified by impedance and velocity spectra. The sensitivity and the sound pressure level of the transducer were characterized. The realized sensitivity of 126.21 μV/Pa at 1 kHz is nearly twenty times of the sensitivity of a sandwich d31 mode transducer. © 2012 Elsevier B.V.

  4. Miniature all-silica optical fiber pressure sensor with an ultrathin uniform diaphragm.

    Science.gov (United States)

    Wang, Wenhui; Wu, Nan; Tian, Ye; Niezrecki, Christopher; Wang, Xingwei

    2010-04-26

    This paper presents an all-silica miniature optical fiber pressure/acoustic sensor based on the Fabry-Perot (FP) interferometric principle. The endface of the etched optical fiber tip and silica thin diaphragm on it form the FP structure. The uniform and thin silica diaphragm was fabricated by etching away the silicon substrate from a commercial silicon wafer that has a thermal oxide layer. The thin film was directly thermally bonded to the endface of the optical fiber thus creating the Fabry-Perot cavity. Thin films with a thickness from 1microm to 3microm have been bonded successfully. The sensor shows good linearity and hysteresis during measurement. A sensor with 0.75 microm-thick diaphragm thinned by post silica etching was demonstrated to have a sensitivity of 11 nm/kPa. The new sensor has great potential to be used as a non-intrusive pressure sensor in a variety of sensing applications.

  5. Visualization of the diaphragm muscle with ultrasound improves diagnostic accuracy of phrenic nerve conduction studies.

    Science.gov (United States)

    Johnson, Nicholas E; Utz, Michael; Patrick, Erica; Rheinwald, Nicole; Downs, Marlene; Dilek, Nuran; Dogra, Vikram; Logigian, Eric L

    2014-05-01

    Evaluation of phrenic neuropathy (PN) with phrenic nerve conduction studies (PNCS) is associated with false negatives. Visualization of diaphragmatic muscle twitch with diaphragm ultrasound (DUS) when performing PNCS may help to solve this problem. We performed bilateral, simultaneous DUS-PNCS in 10 healthy adults and 12 patients with PN. The amplitude of the diaphragm compound muscle action potential (CMAP) (on PNCS) and twitch (on DUS) was calculated. Control subjects had phrenic CMAP (on PCNS). In the 12 patients with PN, 12 phrenic neuropathies were detected. Three of these patients had either significant side-to-side asymmetry or absolute reduction in diaphragm movement that was not detected with PNCS. There were no cases in which the PNCS showed an abnormality but the DUS did not. The addition of DUS to PNCS enhances diagnostic accuracy in PN. Copyright © 2013 Wiley Periodicals, Inc.

  6. Action of the isolated canine diaphragm on the lower ribs at high lung volumes.

    Science.gov (United States)

    De Troyer, André; Wilson, Theodore A

    2014-10-15

    The normal diaphragm has an inspiratory action on the lower ribs, but subjects with chronic obstructive pulmonary disease commonly have an inward displacement of the lateral portions of the lower rib cage during inspiration. This paradoxical displacement, conventionally called 'Hoover's sign', has traditionally been attributed to the direct action of radially oriented diaphragmatic muscle fibres. In the present study, the inspiratory intercostal muscles in all interspaces in anaesthetized dogs were severed so that the diaphragm was the only muscle active during inspiration. The displacements of the lower ribs along the craniocaudal and laterolateral axes and the changes in pleural pressure (∆Ppl) and transdiaphragmatic pressure were measured during occluded breaths and mechanical ventilation at different lung volumes between functional residual capacity (FRC) and total lung capacity. From these data, the separate effects on rib displacement of ∆Ppl and of the force exerted by the diaphragm on the ribs were determined. Isolated spontaneous diaphragm contraction at FRC displaced the lower ribs cranially and outward, but this motion was progressively reversed into a caudal and inward motion as lung volume increased. However, although the force exerted by the diaphragm on the ribs decreased with increasing volume, it continued to displace the ribs cranially and outward. These observations suggest that Hoover's sign is usually caused by the decrease in the zone of apposition and, thus, by the dominant effect of ∆Ppl on the lower ribs, rather than an inward pull from the diaphragm. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

  7. Process engineering and economic evaluations of diaphragm and membrane chlorine cell technologies. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    The chlor-alkali manufacturing technologies of (1), diaphragm cells (2), current technology membrane cells (3), catalytic cathode membrane cells (4), oxygen-cathode membrane cells and to a lesser extent several other related emerging processes are studied. Comparisons have been made on the two bases of (1) conventional industrial economics, and (2) energy consumption. The current diaphragm cell may have a small economic advantage over the other technologies at the plant size of 544 metric T/D (600 T/D). The three membrane cells all consume less energy, with the oxygen-cathode cell being the lowest. The oxygen-cathode cell appears promising as a low energy chlor-alkali cell where there is no chemical market for hydrogen. Federal funding of the oxygen-cathode cell has been beneficial to the development of the technology, to electrochemical cell research, and may help maintain the US's position in the international chlor-alkali technology marketplace. Tax law changes inducing the installation of additional cells in existing plants would produce the quickest reduction in power consumption by the chlor-alkali industry. Alternative technologies such as the solid polymer electrolyte cell, the coupling of diaphragm cells with fuel cells and the dynamic gel diaphragm have a strong potential for reducing chloralkali industry power consumption. Adding up all the recent and expected improvements that have become cost-effective, the electrical energy required to produce a unit of chlorine by 1990 should be only 50% to 60% of that used in 1970. In the United States the majority of the market does not demand salt-free caustic. About 75% of the electrolytic caustic is produced in diaphragm cells and only a small part of that is purified. This study indicates that unless membrane cell costs are greatly reduced or a stronger demand develops for salt-free caustic, the diaphragm cells will remain competitive. (WHK)

  8. Identifying decreased diaphragmatic mobility and diaphragm thickening in interstitial lung disease: the utility of ultrasound imaging

    Science.gov (United States)

    Santana, Pauliane Vieira; Prina, Elena; Albuquerque, André Luis Pereira; Carvalho, Carlos Roberto Ribeiro; Caruso, Pedro

    2016-01-01

    Objective: To investigate the applicability of ultrasound imaging of the diaphragm in interstitial lung disease (ILD). Methods: Using ultrasound, we compared ILD patients and healthy volunteers (controls) in terms of diaphragmatic mobility during quiet and deep breathing; diaphragm thickness at functional residual capacity (FRC) and at total lung capacity (TLC); and the thickening fraction (TF, proportional diaphragm thickening from FRC to TLC). We also evaluated correlations between diaphragmatic dysfunction and lung function variables. Results: Between the ILD patients (n = 40) and the controls (n = 16), mean diaphragmatic mobility was comparable during quiet breathing, although it was significantly lower in the patients during deep breathing (4.5 ± 1.7 cm vs. 7.6 ± 1.4 cm; p < 0.01). The patients showed greater diaphragm thickness at FRC (p = 0.05), although, due to lower diaphragm thickness at TLC, they also showed a lower TF (p < 0.01). The FVC as a percentage of the predicted value (FVC%) correlated with diaphragmatic mobility (r = 0.73; p < 0.01), and an FVC% cut-off value of < 60% presented high sensitivity (92%) and specificity (81%) for indentifying decreased diaphragmatic mobility. Conclusions: Using ultrasound, we were able to show that diaphragmatic mobility and the TF were lower in ILD patients than in healthy controls, despite the greater diaphragm thickness at FRC in the former. Diaphragmatic mobility correlated with ILD functional severity, and an FVC% cut-off value of < 60% was found to be highly accurate for indentifying diaphragmatic dysfunction on ultrasound. PMID:27167428

  9. Aviation Fuel Gauging Sensor Utilizing Multiple Diaphragm Sensors Incorporating Polymer Optical Fiber Bragg Gratings

    DEFF Research Database (Denmark)

    Marques, C. A. F.; Pospori, A.; Saez-Rodriguez, D.

    2016-01-01

    A high-performance fuel gauging sensor is described that uses five diaphragm-based pressure sensors, which are monitored using a linear array of polymer optical fiber Bragg gratings. The sensors were initially characterized using water, revealing a sensitivity of 98 pm/cm for four of the sensors...... of sensors manufactured with a polyurethane-based diaphragm showed no measurable deterioration over a three month period immersed in fuel. These sensors exhibited a sensitivity of 39 pm/cm, which is less than the silicone rubber devices due to the stiffer nature of the polyurethane material used....

  10. WE-G-18C-06: Is Diaphragm Motion a Good Surrogate for Liver Tumor Motion?

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Cai, J; Zheng, C; Czito, B; Palta, M; Yin, F [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Wang, H [School of Information Science and Engineering, Shandong University, Jinan, Shandong (China); Bashir, M [Department of Radiology, Duke University Medical Center, Durham, NC (United States)

    2014-06-15

    Purpose: To investigate whether diaphragm motion is a good surrogate for liver tumor motion by comparing their motion trajectories obtained from cine-MRI. Methods: Fourteen patients with hepatocellular carcinoma (10/14) or liver metastases (4/14) undergoing radiation therapy were included in this study. All patients underwent single-slice 2D cine-MRI simulations across the center of the tumor in three orthogonal planes. Tumor and diaphragm motion trajectories in the superior-inferior (SI), anteriorposterior (AP), and medial-lateral (ML) directions were obtained using the normalized cross-correlation based tracking technique. Agreement between tumor and diaphragm motions was assessed by calculating the phase difference percentage (PDP), intra-class correlation coefficient (ICC), Bland-Altman analysis (Diffs) and paired t-test. The distance (D) between tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between tumor and diaphragm motions. Results: Of all patients, the means (±standard deviations) of PDP were 7.1 (±1.1)%, 4.5 (±0.5)% and 17.5 (±4.5)% in the SI, AP and ML directions, respectively. The means of ICC were 0.98 (±0.02), 0.97 (±0.02), and 0.08 (±0.06) in the SI, AP and ML directions, respectively. The Diffs were 2.8 (±1.4) mm, 2.4 (±1.1) mm, and 2.2 (±0.5) mm in the SI, AP and ML directions, respectively. The p-values derived from the paired t-test were < 0.02 in SI and AP directions, whereas were > 0.58 in ML direction primarily due to the small motion in ML direction. Tumor and diaphragmatic motion had high concordance when the distance between the tumor and tracked diaphragm areas was small. Conclusion: Preliminary results showed that liver tumor motion had good correlations with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be a reliable surrogate for liver tumor motion. NIH (1R21CA165384-01A1), Golfers Against Cancer (GAC

  11. Automated Diaphragm Loading for the LB/TS (Large Blast/Thermal Simulator).

    Science.gov (United States)

    1986-02-28

    103 87 10 925 Q & T 150 126 132 ill 9 775 Q & T 180 151 163 137 7 575 AISI 4140 ANNEALED 90 76 70 59 15 Q & T 125 105 103 87 10 1025 Q & T 150 126 132...carbon steel diaphragm would be 1.9 inches thick, whereas the heat treated alloy steel diaphragm ( AISI 4130) would be 0.44 inches thick. A normalized...EXPOSURE SPEC TREAT @ RT @ 700 F @ RT @ 700 F PERCENT LIMIT ksi ksi ksi ksi in/in F LOW ALLOY STEELS AISI 4130 ANNEALED 90 76 70 59 15 Q & T 125 105

  12. Fabry-Perot Diaphragm Fiber Optic Sensor (DFOS for Acoustic Detection

    Directory of Open Access Journals (Sweden)

    Yan SUN

    2007-10-01

    Full Text Available A diaphragm fiber optic sensor (DFOS solely based on Fabry-Perot multiple beam interference has been designed and fabricated with micro-electric mechanical system (MEMS technology. The silicon diaphragm with an embossed center was designed with an interference gap width kept accurately. The DFOS was verified to be a truly and purely Fabry-Perot device via a critical test. Parallel testing with a Piezoelectric (PZT sensor showed that the DFOS had high sensitivity. The Fabry-Perot DFOS also demonstrated excellent performance in on-line monitoring of Partial Discharge (PD in power transformers.

  13. Effects of cartap on isolated mouse phrenic nerve diaphragm and its related mechanism.

    Science.gov (United States)

    Liao, J W; Kang, J J; Liu, S H; Jeng, C R; Cheng, Y W; Hu, C M; Tsai, S F; Wang, S C; Pang, V F

    2000-06-01

    Cartap, a nereistoxin analogue pesticide, is reported to have no irritation to eyes in rabbits. However, we have demonstrated recently that cartap could actually cause acute death in rabbits via ocular exposure. Our preliminary study with isolated mouse phrenic nerve diaphragms has shown that instead of neuromuscular blockade, cartap caused muscular contracture. The objective of the study was to examine the effect of cartap on the neuromuscular junction in more detail and to investigate its possible underlying mechanism with isolated mouse phrenic nerve diaphragms and sarcoplasmic reticulum (SR) vesicles. Cartap or nereistoxin at various concentrations was added in the organ bath with isolated mouse phrenic nerve diaphragm and both nerve- and muscle-evoked twitches were recorded. Instead of blocking the neuromuscular transmission as nereistoxin did, cartap caused contracture in stimulated or quiescent isolated mouse phrenic nerve diaphragm. Both the cartap-induced muscular contracture force and the time interval to initiate the contracture were dose-dependent. The contracture induced by cartap was not affected by the pretreatment of the diaphragm with the acetylcholine receptor blocker alpha-bungarotoxin; the Na(+) channel blocker tetrodotoxin; or various Ca(2+) channel blockers, NiCl(2), verapamil, and nifedipine. On the contrary, the contracture was significantly inhibited when the diaphragm was pretreated with ryanodine or EGTA containing Ca(2+)-free Krebs solution or in combination. This suggested that both internal and extracellular Ca(2+) might participate in cartap-induced skeletal muscle contracture. Moreover, cartap inhibited the [(3)H]-ryanodine binding to the Ca(2+) release channel of SR in a dose-dependent manner. Additionally, cartap could induce a significant reduction in Ca(2+)-ATPase activity of SR vesicles at a relatively high dose. The results suggested that cartap might cause the influx of extracellular Ca(2+) and the release of internal Ca(2

  14. CONSTRUCTIVE ASPECTS INFLUENCE ON STIFFNESS OF DIAPHRAGM WALLS IN FRAME CONSTRUCTIONS WITH (LIGHT STEEL THIN –WALLED STRUCTURES

    Directory of Open Access Journals (Sweden)

    M. V. Savytskyi

    2010-10-01

    Full Text Available The dependences of influence of structural features of diaphragms of lightweight steel framing braced wall structures on their stiffness are determined. On the basis of dependences the procedure for estimation of stiffness of a diaphragm of any configuration that allows making decisions for maintenance of building stiffness is developed.

  15. Improving the Performance of Two-Stage Gas Guns By Adding a Diaphragm in the Pump Tube

    Science.gov (United States)

    Bogdanoff, D. W.; Miller, Robert J.

    1995-01-01

    Herein, we study the technique of improving the gun performance by installing a diaphragm in the pump tube of the gun. A CFD study is carried out for the 0.28 in. gun in the Hypervelocity Free Flight Radiation (HFF RAD) range at the NASA Ames Research Center. The normal, full-length pump tube is studied as well as two pump tubes of reduced length (approximately 75% and approximately 33% of the normal length). Significant improvements in performance are calculated to be gained for the reduced length pump tubes upon the addition of the diaphragm. These improvements are identified as reductions in maximum pressures in the pump tube and at the projectile base of approximately 20%, while maintaining the projectile muzzle velocity or as increases in muzzle velocity of approximately 0.5 km/sec while not increasing the maximum pressures in the gun. Also, it is found that both guns with reduced pump tube length (with diaphragms) could maintain the performance of gun with the full length pump tube without diaphragms, whereas the guns with reduced pump tube lengths without diaphragms could not. A five-shot experimental investigation of the pump tube diaphragm technique is carried out for the gun with a pump tube length of 75% normal. The CFD predictions of increased muzzle velocity are borne out by the experimental data. Modest, but useful muzzle velocity increases (2.5 - 6%) are obtained upon the installation of a diaphragm, compared to a benchmark shot without a diaphragm.

  16. Effects of acute respiratory and metabolic acidosis on diaphragm muscle obtained from rats.

    Science.gov (United States)

    Michelet, Pierre; Carreira, Serge; Demoule, Alexandre; Amour, Julien; Langeron, Olivier; Riou, Bruno; Coirault, Catherine

    2015-04-01

    Acute respiratory acidosis is associated with alterations in diaphragm performance. The authors compared the effects of respiratory acidosis and metabolic acidosis in the rat diaphragm in vitro. Diaphragmatic strips were stimulated in vitro, and mechanical and energetic variables were measured, cross-bridge kinetics calculated, and the effects of fatigue evaluated. An extracellular pH of 7.00 was obtained by increasing carbon dioxide tension (from 25 to 104 mmHg) in the respiratory acidosis group (n = 12) or lowering bicarbonate concentration (from 24.5 to 5.5 mM) in the metabolic acidosis group (n = 12) and the results compared with a control group (n = 12, pH = 7.40) after 20-min exposure. Respiratory acidosis induced a significant decrease in maximum shortening velocity (-33%, P Respiratory acidosis impaired more relaxation than contraction, as shown by impairment in contraction-relaxation coupling under isotonic (-26%, P acidosis group. In rat diaphragm, acute (20 min) respiratory acidosis induced a marked decrease in the diaphragm contractility, which was not observed in metabolic acidosis.

  17. Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm

    KAUST Repository

    Wang, Zhihong; Yao, Yingbang; Wang, Xianbin; Yue, Weisheng; Chen, Longqing; Zhang, Xixiang

    2013-01-01

    We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr 0.52 Ti 0.48)O 3 (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC

  18. Distinct functions of Crumbs regulating slit diaphragms and endocytosis in Drosophila nephrocytes.

    Science.gov (United States)

    Hochapfel, Florian; Denk, Lucia; Mendl, Gudrun; Schulze, Ulf; Maaßen, Christine; Zaytseva, Yulia; Pavenstädt, Hermann; Weide, Thomas; Rachel, Reinhard; Witzgall, Ralph; Krahn, Michael P

    2017-12-01

    Mammalian podocytes, the key determinants of the kidney's filtration barrier, differentiate from columnar epithelial cells and several key determinants of apical-basal polarity in the conventional epithelia have been shown to regulate podocyte morphogenesis and function. However, little is known about the role of Crumbs, a conserved polarity regulator in many epithelia, for slit-diaphragm formation and podocyte function. In this study, we used Drosophila nephrocytes as model system for mammalian podocytes and identified a conserved function of Crumbs proteins for cellular morphogenesis, nephrocyte diaphragm assembly/maintenance, and endocytosis. Nephrocyte-specific knock-down of Crumbs results in disturbed nephrocyte diaphragm assembly/maintenance and decreased endocytosis, which can be rescued by Drosophila Crumbs as well as human Crumbs2 and Crumbs3, which were both expressed in human podocytes. In contrast to the extracellular domain, which facilitates nephrocyte diaphragm assembly/maintenance, the intracellular FERM-interaction motif of Crumbs is essential for regulating endocytosis. Moreover, Moesin, which binds to the FERM-binding domain of Crumbs, is essential for efficient endocytosis. Thus, we describe here a new mechanism of nephrocyte development and function, which is likely to be conserved in mammalian podocytes.

  19. Morphological and ultrastructural evaluation of the golden retriever muscular dystrophy trachea, lungs, and diaphragm muscle.

    Science.gov (United States)

    Lessa, Thais Borges; de Abreu, Dilayla Kelly; Rodrigues, Márcio Nogueira; Brólio, Marina Pandolphi; Miglino, Maria Angélica; Ambrósio, Carlos Eduardo

    2014-11-01

    Duchenne muscular dystrophy (DMD) is a genetic disease, characterized by atrophy and muscle weakness. The respiratory failure is a common cause of early death in patients with DMD. Golden retriever muscular dystrophy (GRMD) is a canine model which has been extensively used for many advances in therapeutics applications. As the patients with DMD, the GRMD frequently died from cardiac and respiratory failure. Observing the respiratory failure in DMD is one of the major causes of mortality we aimed to describe the morphological and ultrastructural data of trachea, lungs (conductive and respiratory portion of the system), and diaphragm muscle using histological and ultrastructural analysis. The diaphragm muscle showed discontinuous fibers architecture, with different diameter; a robust perimysium inflammatory infiltrate and some muscle cells displayed central nuclei. GRMD trachea and lungs presented collagen fibers and in addition, the GRMD lungs showed higher of levels collagen fibers that could limit the alveolar ducts and alveoli distension. Therefore, the most features observed were the collagen areas and fibrosis. We suggested in this study that the collagen remodeling in the trachea, lungs, and diaphragm muscle may increase fibrosis and affect the trachea, lungs, and diaphragm muscle function that can be a major cause of respiratory failure that occur in patients with DMD. © 2014 Wiley Periodicals, Inc.

  20. Concrete Flow in Diaphragm Wall Panels : A Full-Scale In-Situ Test

    NARCIS (Netherlands)

    Van Dalen, J.H.; Bosch, J.W.; Broere, W.

    2015-01-01

    Flow processes, taking place during the concreting of diaphragm wall panels (D-wall panels), are of great importance for the quality of the wall. During this phase, the bentonite, present in the excavated trench, should be completely replaced by concrete in a controlled way. In literature several

  1. Dexmedetomidine May Produce Extra Protective Effects on Sepsis-induced Diaphragm Injury

    Directory of Open Access Journals (Sweden)

    Jin Wu

    2015-01-01

    Full Text Available Objective: The objective was to evaluate the protective effects of dexmedetomidine (DEX, a selective agonist of α2-adrenergic receptor, on sepsis-induced diaphragm injury and the underlying molecular mechanisms. Data Sources: The data used in this review were mainly from PubMed articles published in English from 1990 to 2015. Study Selection: Clinical or basic research articles were selected mainly according to their level of relevance to this topic. Results: Sepsis could induce severe diaphragm dysfunction and exacerbate respiratory weakness. The mechanism of sepsis-induced diaphragm injury includes the increased inflammatory cytokines and excessive oxidative stress and superfluous production of nitric oxide (NO. DEX can reduce inflammatory cytokines, inhibit nuclear factor-kappaB signaling pathways, suppress the activation of caspase-3, furthermore decrease oxidative stress and inhibit NO synthase. On the basis of these mechanisms, DEX may result in a shorter period of mechanical ventilation in septic patients in clinical practice. Conclusions: Based on this current available evidence, DEX may produce extra protective effects on sepsis-induced diaphragm injury. Further direct evidence and more specific studies are still required to confirm these beneficial effects.

  2. Displacement and resonance behaviors of a piezoelectric diaphragm driven by a double-sided spiral electrode

    KAUST Repository

    Shen, Zhiyuan; Olfatnia, Mohammad; Miao, Jianmin; Wang, Zhihong

    2012-01-01

    This paper presents the design of a lead zirconate titanate (PZT) diaphragm actuated by double-sided patterned electrodes. Au/Cr electrodes were deposited on bulk PZT wafers by sputtering while patterned by a lift-off process. SU-8 thick film

  3. Changes in the Diaphragm Lipid Content after Administration of Streptozotocin and High-Fat Diet Regime

    Directory of Open Access Journals (Sweden)

    Bartlomiej Lukaszuk

    2017-01-01

    Full Text Available The diaphragm is a dome-shaped skeletal muscle indispensable for breathing. Its activity contributes up to 70% of the total ventilatory function at rest. In comparison to other skeletal muscles, it is distinguished by an oxidative phenotype and uninterrupted cyclic contraction pattern. Surprisingly, the research regarding diaphragm diabetic phenotype particularly in the light of lipid-induced insulin resistance is virtually nonexistent. Male Wistar rats were randomly allocated into 3 groups: control, streptozotocin-induced (STZ type-1 diabetes, and rodents fed with high-fat diet (HFD. Additionally, half of the animals from each group were administered with myriocin, a robust, selective inhibitor of ceramide synthesis and, therefore, a potent agent ameliorating insulin resistance. Diaphragm lipid contents were evaluated using chromatography. Fatty acid transporter expression was determined by Western blot. The STZ and HFD rats had increased concentration of lipids, namely, ceramides (CER and diacylglycerols (DAG. Interestingly, this coincided with an increased concentration of long-chain (C ≥ 16 saturated fatty acid species present in both the aforementioned lipid fractions. The CER/DAG accumulation was accompanied by an elevated fatty acid transporter expression (FATP-1 in HFD and FATP-4 in STZ. Surprisingly, we observed a significantly decreased triacylglycerol content in the diaphragms of STZ-treated rats.

  4. Quantification of diaphragm mechanics in Pompe disease using dynamic 3D MRI

    DEFF Research Database (Denmark)

    Mogalle, Katja; Perez-Rovira, Adria; Ciet, Pierluigi

    2016-01-01

    BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification of respira......BACKGROUND: Diaphragm weakness is the main reason for respiratory dysfunction in patients with Pompe disease, a progressive metabolic myopathy affecting respiratory and limb-girdle muscles. Since respiratory failure is the major cause of death among adult patients, early identification...... methodology relies on image registration and lung surface extraction to quantify lung kinematics during breathing. This allows for the extraction of geometry and motion features of the lung that characterize the independent contribution of the diaphragm and the thoracic muscles to the respiratory cycle....... RESULTS: Results in 16 3D+t MRI scans (10 Pompe patients and 6 controls) of a slow expiratory maneuver show that kinematic analysis from dynamic 3D images reveals important additional information about diaphragm mechanics and respiratory muscle involvement when compared to conventional pulmonary function...

  5. Functional assessment of the diaphragm by speckle tracking ultrasound during inspiratory loading

    NARCIS (Netherlands)

    Mos-Oppersma, Eline; Hatam, Nima; Doorduin, Jonne; van der Hoeven, Johannes G.; Marx, Gernot; Goetzenich, Andreas; Fritsch, Sebastian; Heunks, Leo M.A.; Bruells, Christian S.

    2017-01-01

    Assessment of diaphragmatic effort is challenging, especially in critically ill patients in the phase of weaning. Fractional thickening during inspiration assessed by ultrasound has been used to estimate diaphragm effort. It is unknown whether more sophisticated ultrasound techniques such as speckle

  6. Midbrain and medullary control of postinspiratory activity of the crural and costal diaphragm in vivo

    NARCIS (Netherlands)

    Subramanian, Hari H.; Holstege, Gert

    Subramanian HH, Holstege G. Midbrain and medullary control of postinspiratory activity of the crural and costal diaphragm in vivo. J Neurophysiol 105: 2852-2862, 2011. First published March 30, 2011; doi:10.1152/jn.00168.2011.-Studies on brain stem respiratory neurons suggest that eupnea consists of

  7. Where Did the Water Go?: Boyle's Law and Pressurized Diaphragm Water Tanks

    Science.gov (United States)

    Brimhall, James; Naga, Sundar

    2007-01-01

    Many homes use pressurized diaphragm tanks for storage of water pumped from an underground well. These tanks are very carefully constructed to have separate internal chambers for the storage of water and for the air that provides the pressure. One might expect that the amount of water available for use from, for example, a 50-gallon tank would be…

  8. Comparison of clinical utility between diaphragm excursion and thickening change using ultrasonography to predict extubation success

    Science.gov (United States)

    Yoo, Jung-Wan; Lee, Seung Jun; Lee, Jong Deog; Kim, Ho Cheol

    2018-01-01

    Background/Aims Both diaphragmatic excursion and change in muscle thickening are measured using ultrasonography (US) to assess diaphragm function and mechanical ventilation weaning outcomes. However, which parameter can better predict successful extubation remains to be determined. The aim of this study was to compare the clinical utility of these two diaphragmatic parameters to predict extubation success. Methods This study included patients subjected to extubation trial in the medical or surgical intensive care unit of a university-affiliated hospital from May 2015 through February 2016. Diaphragm excursion and percent of thickening change (Δtdi%) were measured using US within 24 hours before extubation. Results Sixty patients were included, and 78.3% (47/60) of these patients were successfully extubated, whereas 21.7% (13/60) were not. The median degree of excursion was greater in patients with extubation success than in those with extubation failure (1.65 cm vs. 0.8 cm, p success had a greater Δtdi% than those with extubation failure (42.1% vs. 22.5%, p = 0.03). The areas under the receiver operating curve for excursion and Δtdi% were 0.836 (95% confidence interval [CI], 0.717 to 0.919) and 0.698 (95% CI, 0.566 to 0.810), respectively (p = 0.017). Conclusions Diaphragm excursion seems more accurate than a change in the diaphragm thickness to predict extubation success. PMID:29050461

  9. Quantification of the variability of diaphragm motion and implications for treatment margin construction

    NARCIS (Netherlands)

    Rit, Simon; van Herk, Marcel; Zijp, Lambert; Sonke, Jan-Jakob

    2012-01-01

    To quantify the variability of diaphragm motion during free-breathing radiotherapy of lung patients and its effect on treatment margins to account for geometric uncertainties. Thirty-three lung cancer patients were analyzed. Each patient had 5-19 cone-beam scans acquired during different treatment

  10. CFD Fuel Slosh Modeling of Fluid-Structure Interaction in Spacecraft Propellant Tanks with Diaphragms

    Science.gov (United States)

    Sances, Dillon J.; Gangadharan, Sathya N.; Sudermann, James E.; Marsell, Brandon

    2010-01-01

    Liquid sloshing within spacecraft propellant tanks causes rapid energy dissipation at resonant modes, which can result in attitude destabilization of the vehicle. Identifying resonant slosh modes currently requires experimental testing and mechanical pendulum analogs to characterize the slosh dynamics. Computational Fluid Dynamics (CFD) techniques have recently been validated as an effective tool for simulating fuel slosh within free-surface propellant tanks. Propellant tanks often incorporate an internal flexible diaphragm to separate ullage and propellant which increases modeling complexity. A coupled fluid-structure CFD model is required to capture the damping effects of a flexible diaphragm on the propellant. ANSYS multidisciplinary engineering software employs a coupled solver for analyzing two-way Fluid Structure Interaction (FSI) cases such as the diaphragm propellant tank system. Slosh models generated by ANSYS software are validated by experimental lateral slosh test results. Accurate data correlation would produce an innovative technique for modeling fuel slosh within diaphragm tanks and provide an accurate and efficient tool for identifying resonant modes and the slosh dynamic response.

  11. Temperature Compensation Fiber Bragg Grating Pressure Sensor Based on Plane Diaphragm

    Science.gov (United States)

    Liang, Minfu; Fang, Xinqiu; Ning, Yaosheng

    2018-03-01

    Pressure sensors are the essential equipments in the field of pressure measurement. In this work, we propose a temperature compensation fiber Bragg grating (FBG) pressure sensor based on the plane diaphragm. The plane diaphragm and pressure sensitivity FBG (PS FBG) are used as the pressure sensitive components, and the temperature compensation FBG (TC FBG) is used to improve the temperature cross-sensitivity. Mechanical deformation model and deformation characteristics simulation analysis of the diaphragm are presented. The measurement principle and theoretical analysis of the mathematical relationship between the FBG central wavelength shift and pressure of the sensor are introduced. The sensitivity and measure range can be adjusted by utilizing the different materials and sizes of the diaphragm to accommodate different measure environments. The performance experiments are carried out, and the results indicate that the pressure sensitivity of the sensor is 35.7 pm/MPa in a range from 0 MPa to 50 MPa and has good linearity with a linear fitting correlation coefficient of 99.95%. In addition, the sensor has the advantages of low frequency chirp and high stability, which can be used to measure pressure in mining engineering, civil engineering, or other complex environment.

  12. Diaphragm remodeling and compensatory respiratory mechanics in a canine model of Duchenne muscular dystrophy.

    Science.gov (United States)

    Mead, A F; Petrov, M; Malik, A S; Mitchell, M A; Childers, M K; Bogan, J R; Seidner, G; Kornegay, J N; Stedman, H H

    2014-04-01

    Ventilatory insufficiency remains the leading cause of death and late stage morbidity in Duchenne muscular dystrophy (DMD). To address critical gaps in our knowledge of the pathobiology of respiratory functional decline, we used an integrative approach to study respiratory mechanics in a translational model of DMD. In studies of individual dogs with the Golden Retriever muscular dystrophy (GRMD) mutation, we found evidence of rapidly progressive loss of ventilatory capacity in association with dramatic morphometric remodeling of the diaphragm. Within the first year of life, the mechanics of breathing at rest, and especially during pharmacological stimulation of respiratory control pathways in the carotid bodies, shift such that the primary role of the diaphragm becomes the passive elastic storage of energy transferred from abdominal wall muscles, thereby permitting the expiratory musculature to share in the generation of inspiratory pressure and flow. In the diaphragm, this physiological shift is associated with the loss of sarcomeres in series (∼ 60%) and an increase in muscle stiffness (∼ 900%) compared with those of the nondystrophic diaphragm, as studied during perfusion ex vivo. In addition to providing much needed endpoint measures for assessing the efficacy of therapeutics, we expect these findings to be a starting point for a more precise understanding of respiratory failure in DMD.

  13. Acute gastric volvulus secondary to eventration of the diaphragm in a child

    Directory of Open Access Journals (Sweden)

    Singal A

    2006-01-01

    Full Text Available We report an 18-month-old boy who presented with acute organoaxial volvulus of stomach secondary to eventration of diaphragm. Clinically, the child exhibited classical triad of epigastric distension, unproductive retching and inability to pass a nasogastric tube. Successful operative management is presented and relevant literature is discussed.

  14. Temperature Compensation Fiber Bragg Grating Pressure Sensor Based on Plane Diaphragm

    Science.gov (United States)

    Liang, Minfu; Fang, Xinqiu; Ning, Yaosheng

    2018-06-01

    Pressure sensors are the essential equipments in the field of pressure measurement. In this work, we propose a temperature compensation fiber Bragg grating (FBG) pressure sensor based on the plane diaphragm. The plane diaphragm and pressure sensitivity FBG (PS FBG) are used as the pressure sensitive components, and the temperature compensation FBG (TC FBG) is used to improve the temperature cross-sensitivity. Mechanical deformation model and deformation characteristics simulation analysis of the diaphragm are presented. The measurement principle and theoretical analysis of the mathematical relationship between the FBG central wavelength shift and pressure of the sensor are introduced. The sensitivity and measure range can be adjusted by utilizing the different materials and sizes of the diaphragm to accommodate different measure environments. The performance experiments are carried out, and the results indicate that the pressure sensitivity of the sensor is 35.7 pm/MPa in a range from 0 MPa to 50 MPa and has good linearity with a linear fitting correlation coefficient of 99.95%. In addition, the sensor has the advantages of low frequency chirp and high stability, which can be used to measure pressure in mining engineering, civil engineering, or other complex environment.

  15. Electrical activity of the diaphragm during nCPAP and high flow nasal cannula

    NARCIS (Netherlands)

    de Waal, C. G.; Hutten, G. J.; Kraaijenga, J. V.; de Jongh, F. H.; van Kaam, A. H.

    2017-01-01

    Objective To determine if the electrical activity of the diaphragm, as measure of neural respiratory drive and breathing effort, changes over time in preterm infants transitioned from nasal continuous positive airway pressure (nCPAP) to high flow nasal cannula (HFNC). Design Prospective

  16. Design recommendations for the optimized continuity diaphragm for prestressed concrete bulb-T beams.

    Science.gov (United States)

    2008-01-01

    This research focused on prestressed concrete bulb-T (PCBT) beams made composite with a cast-in-place concrete deck and continuous over several spans through the use of continuity diaphragms. The current design procedure in AASHTO states that a conti...

  17. Hydrogel based sensor arrays (2 × 2) with perforated piezoresistive diaphragms for metabolic monitoring (in vitro).

    Science.gov (United States)

    Orthner, M P; Lin, G; Avula, M; Buetefisch, S; Magda, J; Rieth, L W; Solzbacher, F

    2010-03-19

    This report details the first experimental results from novel hydrogel sensor array (2 × 2) which incorporates analyte diffusion pores into a piezoresistive diaphragm for the detection of hydrogel swelling pressures and hence chemical concentrations. The sensor assembly was comprised of three components, the active four sensors, HPMA/DMA/TEGDMA (hydroxypropyl methacrylate (HPMA), N,N-dimethylaminoethyl methacrylate (DMA) and crosslinker tetra-ethyleneglycol dimethacrylate (TEGDMA)) hydrogel, and backing plate. Each of the individual sensors of the array can be used with various hydrogels used to measure the presence of a number of stimuli including pH, ionic strength, and glucose concentrations. Ideally, in the future, these sensors will be used for continuous metabolic monitoring applications and implanted subcutaneously. In this paper and to properly characterize the sensor assembly, hydrogels sensitive to changes ionic strength were synthesized using hydroxypropyl methacrylate (HPMA), N,N-dimethylaminoethyl methacrylate (DMA) and crosslinker tetra-ethyleneglycol dimethacrylate (TEGDMA) and inserted into the sensor assembly. This hydrogel quickly and reversibly swells when placed environments of physiological buffer solutions (PBS) with ionic strengths ranging from 0.025 to 0.15 M, making it ideal for proof-of-concept testing and initial characterization. The assembly was wire bonded to a printed circuit board and coated with 3 ± 0.5 μm of Parylene-C using chemical vapor deposition (CVD) to protect the sensor and electrical connections during ionic strength wet testing. Two versions of sensors were fabricated for comparison, the first incorporated diffusion pores into the diaphragm, and the second used a solid diaphragm with perforated backing plate. This new design (perforated diaphragm) was shown to have slightly higher sensitivity than solid diaphragm sensors with separate diffuse backing plates when coupled with the hydrogel. The sensitivities for the 1 mm

  18. Free-Standing β-Ga2O3 Thin Diaphragms

    Science.gov (United States)

    Zheng, Xu-Qian; Lee, Jaesung; Rafique, Subrina; Han, Lu; Zorman, Christian A.; Zhao, Hongping; Feng, Philip X.-L.

    2018-02-01

    Free-standing, very thin, single-crystal β-gallium oxide (β-Ga2O3) diaphragms have been constructed and their dynamical mechanical properties characterized by noncontact, noninvasive optical measurements harnessing the multimode nanomechanical resonances of these suspended nanostructures. We synthesized single-crystal β-Ga2O3 using low-pressure chemical vapor deposition (LPCVD) on a 3C-SiC epilayer grown on Si substrate at temperature of 950°C for 1.5 h. The synthesized single-crystal nanoflakes had widths of ˜ 2 μm to 30 μm and thicknesses of ˜ 20 nm to 140 nm, from which we fabricated free-standing circular drumhead β-Ga2O3 diaphragms with thicknesses of ˜ 23 nm to 73 nm and diameters of ˜ 3.2 μm and ˜ 5.2 μm using a dry stamp-transfer technique. Based on measurements of multiple flexural-mode mechanical resonances using ultrasensitive laser interferometric detection and performing thermal annealing at 250°C for 1.5 h, we quantified the effects of annealing and adsorption of atmospheric gas molecules on the resonant characteristics of the diaphragms. Furthermore, we studied the effects of structural nonidealities on these free-standing β-Ga2O3 nanoscale diaphragms. We present extensive characterization of the mechanical and optical properties of free-standing β-Ga2O3 diaphragms, paving the way for realization of resonant transducers using such nanomechanical structures for use in applications including gas sensing and ultraviolet radiation detection.

  19. Global Proteome Changes in the Rat Diaphragm Induced by Endurance Exercise Training.

    Directory of Open Access Journals (Sweden)

    Kurt J Sollanek

    Full Text Available Mechanical ventilation (MV is a life-saving intervention for many critically ill patients. Unfortunately, prolonged MV results in the rapid development of diaphragmatic atrophy and weakness. Importantly, endurance exercise training results in a diaphragmatic phenotype that is protected against ventilator-induced diaphragmatic atrophy and weakness. The mechanisms responsible for this exercise-induced protection against ventilator-induced diaphragmatic atrophy remain unknown. Therefore, to investigate exercise-induced changes in diaphragm muscle proteins, we compared the diaphragmatic proteome from sedentary and exercise-trained rats. Specifically, using label-free liquid chromatography-mass spectrometry, we performed a proteomics analysis of both soluble proteins and mitochondrial proteins isolated from diaphragm muscle. The total number of diaphragm proteins profiled in the soluble protein fraction and mitochondrial protein fraction were 813 and 732, respectively. Endurance exercise training significantly (P<0.05, FDR <10% altered the abundance of 70 proteins in the soluble diaphragm proteome and 25 proteins of the mitochondrial proteome. In particular, key cytoprotective proteins that increased in relative abundance following exercise training included mitochondrial fission process 1 (Mtfp1; MTP18, 3-mercaptopyruvate sulfurtransferase (3MPST, microsomal glutathione S-transferase 3 (Mgst3; GST-III, and heat shock protein 70 kDa protein 1A/1B (HSP70. While these proteins are known to be cytoprotective in several cell types, the cyto-protective roles of these proteins have yet to be fully elucidated in diaphragm muscle fibers. Based upon these important findings, future experiments can now determine which of these diaphragmatic proteins are sufficient and/or required to promote exercise-induced protection against inactivity-induced muscle atrophy.

  20. Assessment of Diaphragm and External Intercostals Fatigue from Surface EMG using Cervical Magnetic Stimulation

    Directory of Open Access Journals (Sweden)

    Ya-Ju Chang

    2008-03-01

    Full Text Available This study was designed: (1 to test the reliability of surface electromyography (sEMG recording of the diaphragm and external intercostals contractions response to cervical magnetic stimulation (CMS, (2 to examine the amount and the types of inspiratory muscle fatigue that developed after maximum voluntary ventilation (MVV maneuvers.Ten male college students without physical disability (22.1±2.0 years old participated in the study and each completed a control (quiet breathing trial and a fatigue (MVV maneuvers trial sequentially. In the quiet breathing trial, the subjects maintained quiet breathing for five minutes. The subjects performed five maximal static inspiratory efforts and received five CMS before and after the quiet breathing. In the MVV trial, subjects performed five maximal inspiratory efforts and received five CMS before, immediately after, and ten minutes after two sets of MVV maneuvers performed five minutes apart. Maximal inspiratory pressure (PImax, sEMG of diaphragm and external intercostals during maximal static inspiratory efforts and during CMS were recorded. In the quiet breathing trial, high intraclass correlation coefficients (ICC=0.95-0.99 were observed in all the variables. In the MVV trial, the PImax, the EMG amplitude and the median power frequency during maximal static inspiratory efforts significantly decreased in both the diaphragm and the external intercostals immediately after the MVV maneuvers Sensors 2008, 8 2175 (P 0.05. It is concluded that the sEMG recordings of the diaphragm during maximal static inspiratory efforts and in response to CMS allow reproducible sequential assessment of diaphragm contractility. MVV maneuvers resulted in inspiratory muscles fatigue, possibly central fatigue.

  1. Depletion of Pax7+ satellite cells does not affect diaphragm adaptations to running in young or aged mice.

    Science.gov (United States)

    Murach, Kevin A; Confides, Amy L; Ho, Angel; Jackson, Janna R; Ghazala, Lina S; Peterson, Charlotte A; Dupont-Versteegden, Esther E

    2017-10-01

    Satellite cell depletion does not affect diaphragm adaptations to voluntary wheel running in young or aged mice. Satellite cell depletion early in life (4 months of age) has minimal effect on diaphragm phenotype by old age (24 months). Prolonged satellite cell depletion in the diaphragm does not result in excessive extracellular matrix accumulation, in contrast to what has been reported in hind limb muscles. Up-regulation of Pax3 mRNA+ cells after satellite cell depletion in young and aged mice suggests that Pax3+ cells may compensate for a loss of Pax7+ satellite cells in the diaphragm. Future investigations should focus on the role of Pax3+ cells in the diaphragm during adaptation to exercise and ageing. Satellite cell contribution to unstressed diaphragm is higher compared to hind limb muscles, which is probably attributable to constant activation of this muscle to drive ventilation. Whether satellite cell depletion negatively impacts diaphragm quantitative and qualitative characteristics under stressed conditions in young and aged mice is unknown. We therefore challenged the diaphragm with prolonged running activity in the presence and absence of Pax7+ satellite cells in young and aged mice using an inducible Pax7 CreER -R26R DTA model. Mice were vehicle (Veh, satellite cell-replete) or tamoxifen (Tam, satellite cell-depleted) treated at 4 months of age and were then allowed to run voluntarily at 6 months (young) and 22 months (aged). Age-matched, cage-dwelling, Veh- and Tam-treated mice without wheel access served as activity controls. Diaphragm muscles were analysed from young (8 months) and aged (24 months) mice. Satellite cell depletion did not alter diaphragm mean fibre cross-sectional area, fibre type distribution or extracellular matrix content in young or aged mice, regardless of running activity. Resting in vivo diaphragm function was also unaffected by satellite cell depletion. Myonuclear density was maintained in young satellite cell

  2. THE EFFECT OF INNER DIAPHRAGMS AND NON-CONTINUOUS SILL SECTION ON THE STIFFNESS OF AUTOMOTIVE B-PILLAR

    Directory of Open Access Journals (Sweden)

    C.F. Tan

    2017-11-01

    Full Text Available The paper discusses the knowledge on the behaviour of T-frame under specific loading will be obtained by experimental methods in order to investigate the deflection of the vehicle B-pillar or T-frame. In addition, a series of T-frame were designed with inner diaphragm at various location in the sill member in order to investigate the effect of inner diaphragm and noncontinuous closed hat section in the sill member. Lastly, the results from the experimental tests were compared with the finite element analysis results to demonstrate the effectiveness of the inner diaphragm in the automotive B-pillar.

  3. Overexpression of antioxidant enzymes in diaphragm muscle does not alter contraction-induced fatigue or recovery

    Science.gov (United States)

    McClung, Joseph M.; DeRuisseau, Keith C.; Whidden, Melissa A.; Van Remmen, Holly; Richardson, Arlan; Song, Wook; Vrabas, Ioannis S.; Powers, Scott K.

    2010-01-01

    Low levels of reactive oxygen species (ROS) production are necessary to optimize muscle force production in unfatigued muscle. In contrast, sustained high levels of ROS production have been linked to impaired muscle force production and contraction-induced skeletal muscle fatigue. Using genetically engineered mice, we tested the hypothesis that the independent transgenic overexpression of catalase (CAT), copper/zinc superoxide dismutase (CuZnSOD; SOD1) or manganese superoxide dismutase (MnSOD; SOD2) antioxidant enzymes would negatively affect force production in unfatigued diaphragm muscle but would delay the development of muscle fatigue and enhance force recovery after fatiguing contractions. Diaphragm muscle from wild-type littermates (WT) and from CAT, SOD1 and SOD2 overexpressing mice were subjected to an in vitro contractile protocol to investigate the force–frequency characteristics, the fatigue properties and the time course of recovery from fatigue. The CAT, SOD1 and SOD2 overexpressors produced less specific force (in N cm−2) at stimulation frequencies of 20–300 Hz and produced lower maximal tetanic force than WT littermates. The relative development of muscle fatigue and recovery from fatigue were not influenced by transgenic overexpression of any antioxidant enzyme. Morphologically, the mean cross-sectional area (in μm2) of diaphragm myofibres expressing myosin heavy chain type IIA was decreased in both CAT and SOD2 transgenic animals, and the percentage of non-contractile tissue increased in diaphragms from all transgenic mice. In conclusion, our results do not support the hypothesis that overexpression of independent antioxidant enzymes protects diaphragm muscle from contraction-induced fatigue or improves recovery from fatigue. Moreover, our data are consistent with the concept that a basal level of ROS is important to optimize muscle force production, since transgenic overexpression of major cellular antioxidants is associated with

  4. Functional restoration of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization utilizing the functional spinal accessory nerve.

    Science.gov (United States)

    Yang, Ming-liang; Li, Jian-jun; Zhang, Shao-cheng; Du, Liang-jie; Gao, Feng; Li, Jun; Wang, Yu-ming; Gong, Hui-ming; Cheng, Liang

    2011-08-01

    The authors report a case of functional improvement of the paralyzed diaphragm in high cervical quadriplegia via phrenic nerve neurotization using a functional spinal accessory nerve. Complete spinal cord injury at the C-2 level was diagnosed in a 44-year-old man. Left diaphragm activity was decreased, and the right diaphragm was completely paralyzed. When the level of metabolism or activity (for example, fever, sitting, or speech) slightly increased, dyspnea occurred. The patient underwent neurotization of the right phrenic nerve with the trapezius branch of the right spinal accessory nerve at 11 months postinjury. Four weeks after surgery, training of the synchronous activities of the trapezius muscle and inspiration was conducted. Six months after surgery, motion was observed in the previously paralyzed right diaphragm. The lung function evaluation indicated improvements in vital capacity and tidal volume. This patient was able to sit in a wheelchair and conduct outdoor activities without assisted ventilation 12 months after surgery.

  5. The Effects of Phrenic Nerve Degeneration by Axotomy and Crush on the Electrical Activities of Diaphragm Muscles of Rats.

    Science.gov (United States)

    Alkiş, Mehmet Eşref; Kavak, Servet; Sayır, Fuat; Him, Aydin

    2016-03-01

    The aim of this study was to investigate the effect of axotomy and crush-related degeneration on the electrical activities of diaphragm muscle strips of experimental rats. In the present study, twenty-one male Wistar-albino rats were used and divided into three groups. The animals in the first group were not crushed or axotomized and served as controls. Phrenic nerves of the rats in the second and third groups were crushed or axotomized in the diaphragm muscle. Resting membrane potential (RMP) was decreased significantly in both crush and axotomy of diaphragm muscle strips of experimental rats (p phrenic nerves may produce electrical activities in the diaphragm muscle of the rat by depolarization time and half-repolarization time prolonged in crush and axotomy rats.

  6. Variation compensation and analysis on diaphragm curvature analysis for emphysema quantification on whole lung CT scans

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Barr, R. Graham; Yankelevitz, David F.; Henschke, Claudia I.

    2010-03-01

    CT scans allow for the quantitative evaluation of the anatomical bases of emphysema. Recently, a non-density based geometric measurement of lung diagphragm curvature has been proposed as a method for the quantification of emphysema from CT. This work analyzes variability of diaphragm curvature and evaluates the effectiveness of a compensation methodology for the reduction of this variability as compared to emphysema index. Using a dataset of 43 scan-pairs with less than a 100 day time-interval between scans, we find that the diaphragm curvature had a trend towards lower overall variability over emphysema index (95% CI:-9.7 to + 14.7 vs. -15.8 to +12.0), and that the variation of both measures was reduced after compensation. We conclude that the variation of the new measure can be considered comparable to the established measure and the compensation can reduce the apparent variation of quantitative measures successfully.

  7. Enhanced Transmissions Through Three-dimensional Cascade Sharp Waveguide Bends Using C-slit Diaphragms.

    Science.gov (United States)

    Yang, Rui; Hu, Bowei; Zhang, Aofang; Gao, Dongxing; Wang, Hui; Shi, Ayuan; Lei, Zhenya; Yang, Pei

    2017-03-21

    Transmission properties through sharp rectangular waveguide bends are investigated to determine the cut-off bending angles of the wave propagation. We show that a simple metallic diaphragm at the bending corner with properly devised sub-wavelength defect apertures of C-slits would be readily to turn on the transmissions with scarce reflections of the propagating modes, while preserving the integrity of the transmitting fields soon after the bends. In particularly, our design also demonstrates the capability of eliminating all the unwanted cavity resonant transmissions that exist in the three-dimensional cascade sharp waveguide bends, and solely let the desired signals travel along the whole passage of the waveguide. The present approach, using C-slit diaphragms to support the sharp bending behaviors of the guided waves with greatly enhanced transmissions, would be especially effective in constructing novel waveguides and pave the way for the development of more compact and miniaturized electromagnetic systems that exploit these waveguide bends.

  8. Developing a new ultrasonic method to assess diaphragm movement and comparing the accuracy with existing methods

    DEFF Research Database (Denmark)

    Helbo Skaarup, Søren; Løkke, Anders; Laursen, Christian

    2017-01-01

    Introduction: Diaphragm is the most important respiratory muscle. Movement can be evaluated with ultrasound. Currently two different methods are used, M-mode and B-mode. However, diaphragm movement is complex.Aim: We hypothesized that the two existing methods are imprecise as they only measure...... film clips independently to assess inter-rater variability.Results: We found a linear correlation between FVC and diaphragmatic movement. M-mode had Pearson r=0.84 (95%CI 0.76-0.89), B-mode had r=0.68 (95%CI 0.55-0.79) and Area-measurement had r=0.84 (95%CI 0.77-0.90). Inter-rater agreement was r=0...

  9. Structure of diaphragm floor of reactor container, construction module and construction method thereof

    International Nuclear Information System (INIS)

    Hasegawa, Hiroshi; Oikawa, Tadaaki; Ushiroda, Koichi; Matsuura, Tadashi; Komaru, Toshimi; Nemoto, Yoichi; Makita, Tatsuo; Maezawa, Sumito.

    1998-01-01

    A diaphragm floor of a reactor container has a structure comprising iron beams buried in concretes and connection members connecting the iron beams and liners, in which the liners are supported by the iron beams, and the load of the iron reinforced concretes when formed on the liner is supported by the iron beams thereby enabling to construct a diaphragm floor with no or reduced amount of temporary support members. As a result, the construction operation can be promoted by reducing the amount of the temporary support members or making the removing operation of the temporary support members unnecessary. The concrete layer comprises at least two upper and lower layers of a firstly formed concrete layer and a subsequently formed concrete layer, and the iron beams have such a strength capable of enduring the load applied when the firstly formed concrete is placed. (N.H.)

  10. Diaphragm and Lung Ultrasound to Predict Weaning Outcome: Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Llamas-Álvarez, Ana M; Tenza-Lozano, Eva M; Latour-Pérez, Jaime

    2017-12-01

    Deciding the optimal timing for extubation in patients who are mechanically ventilated can be challenging, and traditional weaning predictor tools are not very accurate. The aim of this systematic review and meta-analysis was to assess the accuracy of lung and diaphragm ultrasound for predicting weaning outcomes in critically ill adults. MEDLINE, the Cochrane Library, Web of Science, Scopus, LILACS, Teseo, Tesis Doctorales en Red, and OpenGrey were searched, and the bibliographies of relevant studies were reviewed. Two researchers independently selected studies that met the inclusion criteria and assessed study quality in accordance with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The summary receiver-operating characteristic curve and pooled diagnostic OR (DOR) were estimated by using a bivariate random effects analysis. Sources of heterogeneity were explored by using predefined subgroup analyses and bivariate meta-regression. Nineteen studies involving 1,071 people were included in the study. For diaphragm thickening fraction, the area under the summary receiver-operating characteristic curve was 0.87, and DOR was 21 (95% CI, 11-40). Regarding diaphragmatic excursion, pooled sensitivity was 75% (95% CI, 65-85); pooled specificity, 75% (95% CI, 60-85); and DOR, 10 (95% CI, 4-24). For lung ultrasound, the area under the summary receiver-operating characteristic curve was 0.77, and DOR was 38 (95% CI, 7-198). Based on bivariate meta-regression analysis, a significantly higher specificity for diaphragm thickening fraction and higher sensitivity for diaphragmatic excursion was detected in studies with applicability concerns. Lung and diaphragm ultrasound can help predict weaning outcome, but its accuracy may vary depending on the patient subpopulation. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  11. In vitro glucose uptake by isolated rat hemi-diaphragm study of Aegle marmelos Correa root

    Directory of Open Access Journals (Sweden)

    Subban Ravi

    2009-03-01

    Full Text Available The methanol extract of the root of Aegle marmelos, a medicinal plant, was fractionated into eight fractions using column chromatography. The anti-diabetic activity of all the fractions was studied using the glucose uptake by isolated rat hemi-diaphragm in vitro model. Using the bioassay-guided fractionation, two compounds 1 and 2 were isolated by column chromatography and identified as 6-methyl-4-chromanone and skimmianine respectively by NMR and mass spectral methods.

  12. Investigation by the Rutherford backscattering method of impurity deposited on the T-3M tokamak diaphragm

    International Nuclear Information System (INIS)

    Danelyan, L.S.; Egorova, I.M.; Kulikauskas, V.S.; Baratov, D.G.; Belykh, T.A.

    1994-01-01

    The Rutherford backscattering of helium-4 ions was used for investigation of impurity deposited on the annular graphite diaphragm as a result of the interaction between hydrogen plasma and liquid-metal spray limiter. The experimental RBS spectra distributions of the impurity elements surface densities along the direction from plasma to the chamber wall are presented as depth of the elements. The erosion coefficient of the main liquid-metal limiter element has been estimated

  13. Oxidative damage induced by cigarette smoke exposure in mice: impact on lung tissue and diaphragm muscle,

    Directory of Open Access Journals (Sweden)

    Samanta Portão de Carlos

    2014-08-01

    Full Text Available OBJECTIVE: To evaluate oxidative damage (lipid oxidation, protein oxidation, thiobarbituric acid-reactive substances [TBARS], and carbonylation and inflammation (expression of phosphorylated AMP-activated protein kinase and mammalian target of rapamycin [p-AMPK and p-mTOR, respectively] in the lung parenchyma and diaphragm muscles of male C57BL-6 mice exposed to cigarette smoke (CS for 7, 15, 30, 45, or 60 days. METHODS: Thirty-six male C57BL-6 mice were divided into six groups (n = 6/group: a control group; and five groups exposed to CS for 7, 15, 30, 45, and 60 days, respectively. RESULTS: Compared with control mice, CS-exposed mice presented lower body weights at 30 days. In CS-exposed mice (compared with control mice, the greatest differences (increases in TBARS levels were observed on day 7 in diaphragm-muscle, compared with day 45 in lung tissue; the greatest differences (increases in carbonyl levels were observed on day 7 in both tissue types; and sulfhydryl levels were lower, in both tissue types, at all time points. In lung tissue and diaphragm muscle, p-AMPK expression exhibited behavior similar to that of TBARS. Expression of p-mTOR was higher than the control value on days 7 and 15 in lung tissue, as it was on day 45 in diaphragm muscle. CONCLUSION: Our data demonstrate that CS exposure produces oxidative damage, not only in lung tissue but also (primarily in muscle tissue, having an additional effect on respiratory muscle, as is frequently observed in smokers with COPD.

  14. Rupture traumatique du diaphragme au CHU Gabriel Touré de ...

    African Journals Online (AJOL)

    Rupture traumatique du diaphragme au CHU Gabriel Touré de Bamako, Mali. B T Dembélé, A Togo, A Traoré, Y Sidibé, M Konaté, A A Traoré, A Bah, T Koné, I Tounkara, L Kanté, I Diakité, B Karembé, A Koné, M.I Mangane, G Diallo ...

  15. Evaluation of bubbler/diaphragm techniques to measure surface level in the waste storage tanks

    International Nuclear Information System (INIS)

    Peters, T.J.; Hickman, B.J.; Colson, J.B.

    1993-10-01

    This report describes the results of tests conducted at the Pacific Northwest Laboratory (PNL) to determine if a bubbler technique can be used to determine the surface level in the waste tanks. Two techniques were evaluated. The first technique is a standard bubbler system in which a tube is placed below the surface of the liquid to be measured and air pressure inside a tube is increased until bubbles begin to become emitted from the tube. The air pressure then is a function of the pressure at the bottom of the tube. The second technique involves a system similar to the standard bubbler technique, but instead of bubbles being released into the material to be gauged, air pressure is increased against a diaphragm until enough pressure is applied to overcome the pressure of the liquid at the given depth, at which time the air then flows in a return loop back to a vent. The advantage of the diaphragm system is that it is a sealed system; thus no air is released into the waste tank materials, and it is not possible for the waste tank materials to get into the air flow. Based on the results of the tests conducted in this program, it appears that the bubbler and diaphragm systems that were tested could not be used for accurate measurements of the level in the waste tanks. Both exhibited deposits of simulated waste tank material at the end of the devices which affected the ability of the gauge to accurately determine changes in the surface level even though the measured value of the level was inaccurate. Further investigations into the cause of this inaccuracy may be warranted. Alternate diaphragm materials may improve the performance of this gauge

  16. Investigation of geometric design in piezoelectric microelectromechanical systems diaphragms for ultrasonic energy harvesting

    Science.gov (United States)

    Shi, Qiongfeng; Wang, Tao; Kobayashi, Takeshi; Lee, Chengkuo

    2016-05-01

    Acoustic energy transfer (AET) has been widely used for contactless energy delivery to implantable devices. However, most of the energy harvesters (ultrasonic receivers) for AET are macro-scale transducers with large volume and limited operation bandwidth. Here, we propose and investigate two microelectromechanical systems diaphragm based piezoelectric ultrasonic energy harvesters (PUEHs) as an alternative for AET. The proposed PUEHs consist of micro-scale diaphragm array with different geometric parameter design. Diaphragms in PUEH-1 have large length to width ratio to achieve broadband property, while its energy harvesting performance is compromised. Diaphragms in PUEH-2 have smaller length to width ratio and thinner thickness to achieve both broadband property and good energy harvesting performance. Both PUEHs have miniaturized size and wide operation bandwidth that are ideally suitable to be integrated as power source for implantable biomedical devices. PUEH-1 has a merged -6 dB bandwidth of 74.5% with a central frequency of 350 kHz. PUEH-2 has two separate -6 dB bandwidth of 73.7%/30.8% with central frequencies of 285 kHz/650 kHz. They can adapt to various ultrasonic sources with different working frequency spectrum. Maximum output power is 34.3 nW and 84.3 nW for PUEH-1 and PUEH-2 at 1 mW/cm2 ultrasound intensity input, respectively. The associated power density is 0.734 μW/cm2 and 4.1 μW/cm2, respectively. Better energy harvesting performance is achieved for PUEH-2 because of the optimized length to width ratio and thickness design. Both PUEHs offer more alignment flexibility with more than 40% power when they are in the range of the ultrasound transmitter.

  17. Partial Support Ventilation and Mitochondrial-Targeted Antioxidants Protect against Ventilator-Induced Decreases in Diaphragm Muscle Protein Synthesis.

    Directory of Open Access Journals (Sweden)

    Matthew B Hudson

    Full Text Available Mechanical ventilation (MV is a life-saving intervention in patients in respiratory failure. Unfortunately, prolonged MV results in the rapid development of diaphragm atrophy and weakness. MV-induced diaphragmatic weakness is significant because inspiratory muscle dysfunction is a risk factor for problematic weaning from MV. Therefore, developing a clinical intervention to prevent MV-induced diaphragm atrophy is important. In this regard, MV-induced diaphragmatic atrophy occurs due to both increased proteolysis and decreased protein synthesis. While efforts to impede MV-induced increased proteolysis in the diaphragm are well-documented, only one study has investigated methods of preserving diaphragmatic protein synthesis during prolonged MV. Therefore, we evaluated the efficacy of two therapeutic interventions that, conceptually, have the potential to sustain protein synthesis in the rat diaphragm during prolonged MV. Specifically, these experiments were designed to: 1 determine if partial-support MV will protect against the decrease in diaphragmatic protein synthesis that occurs during prolonged full-support MV; and 2 establish if treatment with a mitochondrial-targeted antioxidant will maintain diaphragm protein synthesis during full-support MV. Compared to spontaneously breathing animals, full support MV resulted in a significant decline in diaphragmatic protein synthesis during 12 hours of MV. In contrast, diaphragm protein synthesis rates were maintained during partial support MV at levels comparable to spontaneous breathing animals. Further, treatment of animals with a mitochondrial-targeted antioxidant prevented oxidative stress during full support MV and maintained diaphragm protein synthesis at the level of spontaneous breathing animals. We conclude that treatment with mitochondrial-targeted antioxidants or the use of partial-support MV are potential strategies to preserve diaphragm protein synthesis during prolonged MV.

  18. Partial Support Ventilation and Mitochondrial-Targeted Antioxidants Protect against Ventilator-Induced Decreases in Diaphragm Muscle Protein Synthesis.

    Science.gov (United States)

    Hudson, Matthew B; Smuder, Ashley J; Nelson, W Bradley; Wiggs, Michael P; Shimkus, Kevin L; Fluckey, James D; Szeto, Hazel H; Powers, Scott K

    2015-01-01

    Mechanical ventilation (MV) is a life-saving intervention in patients in respiratory failure. Unfortunately, prolonged MV results in the rapid development of diaphragm atrophy and weakness. MV-induced diaphragmatic weakness is significant because inspiratory muscle dysfunction is a risk factor for problematic weaning from MV. Therefore, developing a clinical intervention to prevent MV-induced diaphragm atrophy is important. In this regard, MV-induced diaphragmatic atrophy occurs due to both increased proteolysis and decreased protein synthesis. While efforts to impede MV-induced increased proteolysis in the diaphragm are well-documented, only one study has investigated methods of preserving diaphragmatic protein synthesis during prolonged MV. Therefore, we evaluated the efficacy of two therapeutic interventions that, conceptually, have the potential to sustain protein synthesis in the rat diaphragm during prolonged MV. Specifically, these experiments were designed to: 1) determine if partial-support MV will protect against the decrease in diaphragmatic protein synthesis that occurs during prolonged full-support MV; and 2) establish if treatment with a mitochondrial-targeted antioxidant will maintain diaphragm protein synthesis during full-support MV. Compared to spontaneously breathing animals, full support MV resulted in a significant decline in diaphragmatic protein synthesis during 12 hours of MV. In contrast, diaphragm protein synthesis rates were maintained during partial support MV at levels comparable to spontaneous breathing animals. Further, treatment of animals with a mitochondrial-targeted antioxidant prevented oxidative stress during full support MV and maintained diaphragm protein synthesis at the level of spontaneous breathing animals. We conclude that treatment with mitochondrial-targeted antioxidants or the use of partial-support MV are potential strategies to preserve diaphragm protein synthesis during prolonged MV.

  19. Monte Carlo analysis of thermal transpiration effects in capacitance diaphragm gauges with helicoidal baffle system

    International Nuclear Information System (INIS)

    Vargas, M; Stefanov, S; Wüest, M

    2012-01-01

    The Capacitance Diaphragm Gauge (CDG) is one of the most widely used vacuum gauges in low and middle vacuum ranges. This device consists basically of a very thin ceramic or metal diaphragm which forms one of the electrodes of a cap acitor. The pressure is determined by measuring the variation in the capacitance due to the deflection of the diaphragm caused by the pressure difference established across the membrane. In order to minimize zero drift, some CDGs are operated keeping the sensor at a higher temperature. This difference in the temperature between the sensor and the vacuum chamber makes the behaviour of the gauge non-linear due to thermal transpiration effects. This effect becomes more significant when we move from the transitional flow to the free molecular regime. Besides, CDGs may incorporate different baffle systems to avoid the condensation on the membrane or its contamination. In this work, the thermal transpiration effect on the behaviour of a rarefied gas and on the measurements in a CDG with a helicoidal baffle system is investigated by using the Direct Simulation Monte Carlo method (DSMC). The study covers the behaviour of the system under the whole range of rarefaction, from the continuum up to the free molecular limit and the results are compared with empirical results. Moreover, the influence of the boundary conditions on the thermal transpiration effects is investigated by using Maxwell boundary conditions.

  20. Exercise Prevents Diaphragm Wasting Induced by Cigarette Smoke through Modulation of Antioxidant Genes and Metalloproteinases

    Directory of Open Access Journals (Sweden)

    Gracielle Vieira Ramos

    2018-01-01

    Full Text Available Background. The present study aimed to analyze the effects of physical training on an antioxidant canonical pathway and metalloproteinases activity in diaphragm muscle in a model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD. Methods. Male mice were randomized into control, smoke, exercise, and exercise + smoke groups, which were maintained in trial period of 24 weeks. Gene expression of kelch-like ECH-associated protein 1; nuclear factor erythroid-2 like 2; and heme-oxygenase1 by polymerase chain reaction was performed. Metalloproteinases 2 and 9 activities were analyzed by zymography. Exercise capacity was evaluated by treadmill exercise test before and after the protocol. Results. Aerobic training inhibited diaphragm muscle wasting induced by cigarette smoke exposure. This inhibition was associated with improved aerobic capacity in those animals that were submitted to 24 weeks of aerobic training, when compared to the control and smoke groups, which were not submitted to training. The aerobic training also downregulated the increase of matrix metalloproteinases (MMP-2 and MMP-9 and upregulated antioxidant genes, such as nuclear factor erythroid-2 like 2 (NRF2 and heme-oxygenase1 (HMOX1, in exercise + smoke group compared to smoke group. Conclusions. Treadmill aerobic training protects diaphragm muscle wasting induced by cigarette smoke exposure involving upregulation of antioxidant genes and downregulation of matrix metalloproteinases.

  1. Comparison of stethoscope bell and diaphragm, and of stethoscope tube length, for clinical blood pressure measurement.

    Science.gov (United States)

    Liu, Chengyu; Griffiths, Clive; Murray, Alan; Zheng, Dingchang

    2016-06-01

    This study investigated the effect of stethoscope side and tube length on auscultatory blood pressure (BP) measurement. Thirty-two healthy participants were studied. For each participant, four measurements with different combinations of stethoscope characteristics (bell or diaphragm side, standard or short tube length) were each recorded at two repeat sessions, and eight Korotkoff sound recordings were played twice on separate days to one experienced listener to determine the systolic and diastolic BPs (SBP and DBP). Analysis of variance was carried out to study the measurement repeatability between the two repeat sessions and between the two BP determinations on separate days, as well as the effects of stethoscope side and tube length. There was no significant paired difference between the repeat sessions and between the repeat determinations for both SBP and DBP (all P-values>0.10, except the repeat session for SBP using short tube and diaphragm). The key result was that there was a small but significantly higher DBP on using the bell in comparison with the diaphragm (0.66 mmHg, P=0.007), and a significantly higher SBP on using the short tube in comparison with the standard length (0.77 mmHg, P=0.008). This study shows that stethoscope characteristics have only a small, although statistically significant, influence on clinical BP measurement. Although this helps understand the measurement technique and resolves questions in the published literature, the influence is not clinically significant.

  2. High temperature energy harvesters utilizing ALN/3C-SiC composite diaphragms

    Science.gov (United States)

    Lai, Yun-Ju; Li, Wei-Chang; Felmetsger, Valery V.; Senesky, Debbie G.; Pisano, Albert P.

    2014-06-01

    Microelectromechanical systems (MEMS) energy harvesting devices aiming at powering wireless sensor systems for structural health monitoring in harsh environments are presented. For harsh environment wireless sensor systems, sensor modules are required to operate at elevated temperatures (> 250°C) with capabilities to resist harsh chemical conditions, thereby the use of battery-based power sources becomes challenging and not economically efficient if considering the required maintenance efforts. To address this issue, energy harvesting technology is proposed to replace batteries and provide a sustainable power source for the sensor systems towards autonomous harsh environment wireless sensor networks. In particular, this work demonstrates a micromachined aluminum nitride/cubic silicon carbide (AlN/3C-SiC) composite diaphragm energy harvester, which enables high temperature energy harvesting from ambient pulsed pressure sources. The fabricated device yields an output power density of 87 μW/cm2 under 1.48-psi pressure pulses at 1 kHz while connected to a 14.6-kΩ load resistor. The effects of pulse profile on output voltage have been studied, showing that the output voltage can be maximized by optimizing the diaphragm resonance frequency based on specific pulse characteristics. In addition, temperature dependence of the diaphragm resonance frequency over the range of 20°C to 600°C has been investigated and the device operation at temperatures as high as 600°C has been verified.

  3. Advanced performance of small diaphragm vacuum pumps through the use of mechatronics

    Science.gov (United States)

    Lachenmann, R.; Dirscherl, J.

    Oil-free diaphragm vacuum pumps have proven to be the best way in vacuum generation for the chemical laboratory and they also find increasing use as backing pumps for modern wide-range turbo molecular pumps. The majority of vacuum pumps in practical use pump only a rather small percentage of their lifetime at full gas load. A pump backing a turbo molecular pump does not have to pump a significant gas load when the high-vacuum pump is running at ultimate vacuum pressure. Also, for a vacuum distillation the vacuum pump has to operate at full speed only at the beginning to lower the pressure inside the system to a vacuum level where evaporation starts. In a rather leak-tight system the distillation process continues by evaporating from the hot liquid and condensing at the cold condenser without the need of a mechanical vacuum pump. Rotational speed controlled diaphragm pumps are now available through progress in mechatronics and offer high pumping speed capability for fast pump-down cycles and precise pressure control for distillations. At low gas load the rotational speed can be reduced, improving maintenance intervals, power consumption, noise, vibration and - surprisingly - also ultimate pressure. The different behaviour in pumping speed and ultimate pressure of rotational speed controlled diaphragm pumps in comparison to constant-speed pumps is related to the mechanical properties of the valves and gas dynamics .

  4. Tumor motion prediction with the diaphragm as a surrogate: a feasibility study

    International Nuclear Information System (INIS)

    Cervino, Laura I; Jiang Yan; Sandhu, Ajay; Jiang, Steve B

    2010-01-01

    We have previously assessed the use of the diaphragm as a surrogate for predicting real-time tumor position with linear models built with training data extracted from the same treatment fraction (Cervino et al 2009 Phys. Med. Biol. 54 3529-41). However, practical use in the clinical setting requires the capability of predicting tumor position throughout the treatment course using a model built at the beginning of the course. We evaluate the inter-fraction applicability of linear models to predict superior-inferior tumor position based on diaphragm position using 21 fluoroscopic sequences from five lung cancer patients. Tumor position is predicted with models built during the first fluoroscopic sequence of each patient. Other fluoroscopic sets are registered to the first set with five different methods. The mean localization prediction error and maximum error at a 95% confidence level averaged over all patients are found to be 1.2 mm and 2.9 mm, respectively, for bony registration and 1.2 mm and 2.8 mm, respectively, for registration based on the mean position of the tumor in the first two breathing cycles. Other registration methods produce larger prediction errors. In the clinical setting, this prediction error could be added as a margin to the target volume. We therefore conclude that it is feasible to predict lung tumor motion with diaphragm with sufficient accuracy in the clinical setting. (note)

  5. Dystrophic phenotype improvement in the diaphragm muscle of mdx mice by diacerhein.

    Directory of Open Access Journals (Sweden)

    Rafael Dias Mâncio

    Full Text Available Chronic inflammation and oxidative stress are striking features of Duchenne muscular dystrophy disease. Diacerhein is an anthraquinone, which exhibits anti-inflammatory and antioxidant properties. Based on their actions, the present study evaluated the effects of diacerhein against myonecrosis, oxidative stress and inflammatory response in the diaphragm muscle of mdx mice and compared these results to current treatment widely used in DMD patients, with a main focus on the impact of prednisone. The results demonstrated that diacerhein treatment prevented muscle damage indicated by a decrease in the IgG uptake by muscle fibers, lower CK levels in serum, reduction of fibers with central nuclei with a concomitant increase in fibers with peripheral nuclei. It also had an effect on the inflammatory process, decreasing the inflammatory area, macrophage staining and TNF-α and IL-1β content. Regarding oxidative stress, diacerhein treatment was effective in reducing the ROS and lipid peroxidation in the diaphragm muscle from mdx mice. Compared to prednisone treatment, our findings demonstrated that diacerhein treatment improved the dystrophic phenotype in the diaphragm muscle of mdx mice similar to that of glucocorticoid therapy. In this respect, this work suggests that diacerhein has a potential use as an alternative drug in dystrophinopathy treatment and recommends that its anti-inflammatory and antioxidants properties in the dystrophic muscle should be better understood.

  6. Automatic assessment of average diaphragm motion trajectory from 4DCT images through machine learning.

    Science.gov (United States)

    Li, Guang; Wei, Jie; Huang, Hailiang; Gaebler, Carl Philipp; Yuan, Amy; Deasy, Joseph O

    2015-12-01

    To automatically estimate average diaphragm motion trajectory (ADMT) based on four-dimensional computed tomography (4DCT), facilitating clinical assessment of respiratory motion and motion variation and retrospective motion study. We have developed an effective motion extraction approach and a machine-learning-based algorithm to estimate the ADMT. Eleven patients with 22 sets of 4DCT images (4DCT1 at simulation and 4DCT2 at treatment) were studied. After automatically segmenting the lungs, the differential volume-per-slice (dVPS) curves of the left and right lungs were calculated as a function of slice number for each phase with respective to the full-exhalation. After 5-slice moving average was performed, the discrete cosine transform (DCT) was applied to analyze the dVPS curves in frequency domain. The dimensionality of the spectrum data was reduced by using several lowest frequency coefficients ( f v ) to account for most of the spectrum energy (Σ f v 2 ). Multiple linear regression (MLR) method was then applied to determine the weights of these frequencies by fitting the ground truth-the measured ADMT, which are represented by three pivot points of the diaphragm on each side. The 'leave-one-out' cross validation method was employed to analyze the statistical performance of the prediction results in three image sets: 4DCT1, 4DCT2, and 4DCT1 + 4DCT2. Seven lowest frequencies in DCT domain were found to be sufficient to approximate the patient dVPS curves ( R = 91%-96% in MLR fitting). The mean error in the predicted ADMT using leave-one-out method was 0.3 ± 1.9 mm for the left-side diaphragm and 0.0 ± 1.4 mm for the right-side diaphragm. The prediction error is lower in 4DCT2 than 4DCT1, and is the lowest in 4DCT1 and 4DCT2 combined. This frequency-analysis-based machine learning technique was employed to predict the ADMT automatically with an acceptable error (0.2 ± 1.6 mm). This volumetric approach is not affected by the presence of the lung tumors

  7. Feasibility of navigator setting on the left diaphragm for whole-heart coronary MRA. A study in healthy volunteers

    International Nuclear Information System (INIS)

    Watanabe, Kunihiro; Suzuki, Takayoshi; Maruyama, Kazuhiro; Noda, Mayumi; Fujita, Mitsuo; Morita, Satoru; Ohnishi, Takahiro

    2009-01-01

    We prospectively compared the quality of images obtained by navigator setting on the left and right diaphragm on whole-heart coronary magnetic resonance angiography (WHCMRA). In 10 healthy volunteers, we performed free-breathing, 3-dimensional segmented true fast imaging with steady-state precession (trueFISP) WHCMRA by setting the navigator on the left and right diaphragm in random order. For the left diaphragm, we set the navigator outside the scope of the heart to avoid the influence on coronary arteries. We compared image acquisition time and visible length of coronary arteries using paired t-test and subjective image quality on a 4-point scale (1, poor; 4, excellent) using Wilcoxon signed-rank test. Mean overall subjective image quality was significantly better in the left diaphragm than the right (3.3±0.7 versus 2.9±0.9, P=0.02). Mean overall visible length of the coronary arteries was significantly better in the left diaphragm than the right (115.4±31.1 vs. 112.6±29.9 mm, P=0.02). Mean acquisition time between the left and right diaphragm was not significantly different (15.6±5.0 versus 16.0±5.7 min, P=0.79). In this small group of healthy volunteers, navigator setting for WHCMRA was superior on the left diaphragm than the right; however, feasibility of the technique requires additional consideration in a larger group of actual patients. (author)

  8. SU-G-BRA-08: Diaphragm Motion Tracking Based On KV CBCT Projections with a Constrained Linear Regression Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Wei, J [City College of New York, New York, NY (United States); Chao, M [The Mount Sinai Medical Center, New York, NY (United States)

    2016-06-15

    Purpose: To develop a novel strategy to extract the respiratory motion of the thoracic diaphragm from kilovoltage cone beam computed tomography (CBCT) projections by a constrained linear regression optimization technique. Methods: A parabolic function was identified as the geometric model and was employed to fit the shape of the diaphragm on the CBCT projections. The search was initialized by five manually placed seeds on a pre-selected projection image. Temporal redundancies, the enabling phenomenology in video compression and encoding techniques, inherent in the dynamic properties of the diaphragm motion together with the geometrical shape of the diaphragm boundary and the associated algebraic constraint that significantly reduced the searching space of viable parabolic parameters was integrated, which can be effectively optimized by a constrained linear regression approach on the subsequent projections. The innovative algebraic constraints stipulating the kinetic range of the motion and the spatial constraint preventing any unphysical deviations was able to obtain the optimal contour of the diaphragm with minimal initialization. The algorithm was assessed by a fluoroscopic movie acquired at anteriorposterior fixed direction and kilovoltage CBCT projection image sets from four lung and two liver patients. The automatic tracing by the proposed algorithm and manual tracking by a human operator were compared in both space and frequency domains. Results: The error between the estimated and manual detections for the fluoroscopic movie was 0.54mm with standard deviation (SD) of 0.45mm, while the average error for the CBCT projections was 0.79mm with SD of 0.64mm for all enrolled patients. The submillimeter accuracy outcome exhibits the promise of the proposed constrained linear regression approach to track the diaphragm motion on rotational projection images. Conclusion: The new algorithm will provide a potential solution to rendering diaphragm motion and ultimately

  9. SU-G-BRA-08: Diaphragm Motion Tracking Based On KV CBCT Projections with a Constrained Linear Regression Optimization

    International Nuclear Information System (INIS)

    Wei, J; Chao, M

    2016-01-01

    Purpose: To develop a novel strategy to extract the respiratory motion of the thoracic diaphragm from kilovoltage cone beam computed tomography (CBCT) projections by a constrained linear regression optimization technique. Methods: A parabolic function was identified as the geometric model and was employed to fit the shape of the diaphragm on the CBCT projections. The search was initialized by five manually placed seeds on a pre-selected projection image. Temporal redundancies, the enabling phenomenology in video compression and encoding techniques, inherent in the dynamic properties of the diaphragm motion together with the geometrical shape of the diaphragm boundary and the associated algebraic constraint that significantly reduced the searching space of viable parabolic parameters was integrated, which can be effectively optimized by a constrained linear regression approach on the subsequent projections. The innovative algebraic constraints stipulating the kinetic range of the motion and the spatial constraint preventing any unphysical deviations was able to obtain the optimal contour of the diaphragm with minimal initialization. The algorithm was assessed by a fluoroscopic movie acquired at anteriorposterior fixed direction and kilovoltage CBCT projection image sets from four lung and two liver patients. The automatic tracing by the proposed algorithm and manual tracking by a human operator were compared in both space and frequency domains. Results: The error between the estimated and manual detections for the fluoroscopic movie was 0.54mm with standard deviation (SD) of 0.45mm, while the average error for the CBCT projections was 0.79mm with SD of 0.64mm for all enrolled patients. The submillimeter accuracy outcome exhibits the promise of the proposed constrained linear regression approach to track the diaphragm motion on rotational projection images. Conclusion: The new algorithm will provide a potential solution to rendering diaphragm motion and ultimately

  10. 900 MW CP1 nuclear steam turbine retrofit thermal effects on low pressure diaphragms

    International Nuclear Information System (INIS)

    Buguin, A.; Gruau, P.; Lamarque, F.; Huggett, J.

    2015-01-01

    The steam turbines of the Koeberg units 1 and 2 operated by ESKOM in South Africa have been retrofitted in order to mitigate the generic problems of stress corrosion cracking of the original shrunk-on disk rotor design. As already done in Belgium and France, the implementation of welded rotors improves the turbine reliability and availability. Moreover, the new technology implemented associated with a new steam path allows a significant performance improvement. With a wealth of experience in CP1 retrofit, ALSTOM has put in place new technical features in the steam path in order to further improve the heat rate. Among them, steam balance holes drilled in the rotor disks have exacerbated the thermal sensitivity of the LP diaphragms. During the commissioning of the Unit 1 LP turbines following the retrofit, the load increase led to unacceptable vibrations. An investigation program was launched to determine the root causes of the problem. This paper presents the findings following the turbine inspection, as well as the recommendations and modifications to allow a smooth return to service of the unit. In addition, the results of the root cause analysis of the vibration incident are explained. Based on finite element calculations and site measurements, ALSTOM has established that the diaphragm thermal behavior, intensified by the steam balance holes, has led to radial rubbing. It was also established that the phenomena had no effect on the diaphragms mechanical integrity. Design changes have been proposed to ensure a safe and reliable long term operation of the units. These modifications have been successfully implemented onto the Koeberg Unit 2 Nuclear Steam Turbine commissioned in November 2012. (authors)

  11. Percutaneous Radiofrequency Ablation for the Hepatocellular Carcinoma Abutting the Diaphragm: Assessment of Safety and Therapeutic Efficacy

    International Nuclear Information System (INIS)

    Kang, Tae Wook; Rhim, Hyun Chul; Kim, Eun Young; Kim, Young Sun; Choi, Dong Il; Lee, Won Jae; Lim, Hyo K.

    2009-01-01

    To assess the safety and therapeutic efficacy of a percutaneous radiofrequency (RF) ablation for the hepatocellular carcinoma (HCC) abutting the diaphragm. We retrospectively assessed 80 patients who underwent a percutaneous RF ablation for a single nodular (< 4 cm) HCC over the last four years. Each patient underwent an ultrasound-guided RF ablation using internally cooled electrodes for the first-line treatment. We divided patients into two subgroups based on whether the index tumor was abutting (less than 5 mm) the diaphragm or not: group A (abutting; n = 31) versus group B (non-abutting; n = 49). We compared the two subgroups for complications and therapeutic efficacy using image and the review of medical records. The statistical assessment included an independent t-test, Fisher's exact test, and chi-square test. The assessment of the diaphragmatic swelling at CT immediately following the procedure was more severe in group A than group B (mean thickness change:1.44 vs. 0.46 mm, p = 0.00). Further, right shoulder pain was more common in group A than B (p = 0.01). Although minor complications (hemothorax 1 case, pleural effusion 1 case) were noted only in group A, no major thoracic complication occurred in either group. The technical success rate was lower in group A than group B (84% vs. 98%, p = 0.03). As well, the primary and secondary technique effectiveness rates in group A and group B were 90% versus 98% (p = 0.29) and 79% versus 91% (p = 0.25), respectively. The local tumor progression rate was higher in group A than in group B (29% vs. 6%, p = 0.02). We found that the percutaneous RF ablation for the HCC abutting the diaphragm is a safe procedure without major complications. However, it is less effective with regard to technical success and local tumor control

  12. Estimation of diaphragm length in patients with severe chronic obstructive pulmonary disease.

    Science.gov (United States)

    McKenzie, D K; Gorman, R B; Tolman, J; Pride, N B; Gandevia, S C

    2000-11-01

    In patients with advanced chronic obstructive pulmonary disease (COPD) diaphragm function may be compromised because of reduced muscle fibre length. Diaphragm length (L(Di)) can be estimated from measurements of transverse diameter of the rib cage (D(Rc)) and the length of the zone of apposition (L(Zapp)) in healthy subjects, but this method has not been validated in patients with COPD. Postero-anterior chest radiographs were obtained at total lung capacity (TLC), functional residual capacity (FRC) and residual volume (RV) in nine male patients with severe COPD (mean [S.D.]; FEV(1), 23 [6] %pred.; FRC, 199 [15] %pred.). Radiographs taken at TLC were used to identify the lateral costal insertions of the diaphragm (L(Zapp) assumed to approach zero at TLC). L(Di) was measured directly and also estimated from measurements of L(Zapp) and D(Rc) using a prediction equation derived from healthy subjects. The estimation of L(Di) was highly accurate with an intraclass correlation coefficient of 0.93 and 95% CI of approximately +/-8% of the true value. L(Di) decreased from 426 (64) mm at RV to 305 (31) mm at TLC. As there were only small and variable changes in D(Rc) across the lung volume range, most of the L(Di) changes occurred in the zone of apposition. Additional studies showed that measurements of L(Di) from PA and lateral radiographs performed at different lung volumes were tightly correlated. These results suggest that non-invasive measurements of L(Zapp) in the coronal plane (e.g. using ultrasonography) and D(Rc) (e.g. using magnetometers) can be used to provide an accurate estimate of L(Di) in COPD patients.

  13. Thermal Stresses Analysis and Optimized TTP Processes to Achieved CNT-Based Diaphragm for Thin Panel Speakers

    Directory of Open Access Journals (Sweden)

    Feng-Min Lai

    2016-01-01

    Full Text Available Industrial companies popularly used the powder coating, classing, and thermal transfer printing (TTP technique to avoid oxidation on the metallic surface and stiffened speaker diaphragm. This study developed a TTP technique to fabricate a carbon nanotubes (CNTs stiffened speaker diaphragm for thin panel speaker. The self-developed TTP stiffening technique did not require a high curing temperature that decreased the mechanical property of CNTs. In addition to increasing the stiffness of diaphragm substrate, this technique alleviated the middle and high frequency attenuation associated with the smoothing sound pressure curve of thin panel speaker. The advantage of TTP technique is less harmful to the ecology, but it causes thermal residual stresses and some unstable connections between printed plates. Thus, this study used the numerical analysis software (ANSYS to analyze the stress and thermal of work piece which have not delaminated problems in transfer interface. The Taguchi quality engineering method was applied to identify the optimal manufacturing parameters. Finally, the optimal manufacturing parameters were employed to fabricate a CNT-based diaphragm, which was then assembled onto a speaker. The result indicated that the CNT-based diaphragm improved the sound pressure curve smoothness of the speaker, which produced a minimum high frequency dip difference (ΔdB value.

  14. High Power DC Diaphragm Discharge Excited in a Vapor Bubble for the Treatment of Water

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Člupek, Martin; Babický, Václav; Doležalová, Eva; Sisrová, Irena; Maršálková, Eliška; Maršálek, Blahoslav

    2013-01-01

    Roč. 33, č. 1 (2013), s. 83-95 ISSN 0272-4324 R&D Projects: GA AV ČR IAAX00430802; GA ČR(CZ) GD104/09/H080 Institutional support: RVO:61389021 ; RVO:67985939 Keywords : Diaphragm discharge * Water * Hydrogen peroxide * Phenol * Bacteria * Algae Subject RIV: BL - Plasma and Gas Discharge Physics; EF - Botanics (BU-J) Impact factor: 1.599, year: 2013 http://link.springer.com/content/pdf/10.1007%2Fs11090-012-9432-6.pdf

  15. Innervation of periesophageal region of cat's diaphragm - Implication for studies of control of vomiting

    Science.gov (United States)

    Tan, L. K.; Miller, A. D.

    1986-01-01

    The extent of the region of the diaphragm around the esophagus that displays greatly reduced activity during the expulsive phase of vomiting was determined from electromyographic studies in cats to be about 0.75-1.0 cm from the esophagus. Horseradish peroxidase injected into this region retrogradely labeled motoneurons throughout most of the rostral-caudal extent of the phrenic nucleus, with the exception of caudal C6 and rostral C7. This widespread intermingling of motoneurons that innervate the region of reduced activity with other phrenic motoneurons creates a difficulty for needed follow-up studies of diaphragmatic control during vomiting.

  16. Acceptability of an existing, female-controlled contraceptive method that could potentially protect against HIV: a comparison of diaphragm users and other method users.

    Science.gov (United States)

    Bird, Sheryl Thorburn; Harvey, S Marie; Maher, Julie E; Beckman, Linda J

    2004-01-01

    The diaphragm, an internal barrier contraceptive device, is a candidate for a female-controlled method for preventing human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). This study's objective was to examine how women who use the diaphragm differ from women using the pill and/or condoms with respect to factors hypothesized to influence the acceptability of contraceptive methods. Our goal was to increase understanding of who finds the diaphragm acceptable and why. We conducted a cross-sectional telephone survey with selected female members of a managed care organization. For this analysis, we limited the sample to 585 women currently using the diaphragm (n = 196), pill (n = 200), condoms (n = 132), or pill and condoms (n = 57). We conducted bivariate analyses and multinomial logistic regression analyses to assess the associations between selected characteristics and diaphragm use. Diaphragm use was significantly associated with several variables. Of particular interest, placing less importance on hormonal method characteristics was significantly associated with diaphragm use (versus use of the pill, condoms, or both). Placing more importance on barrier method attributes was significantly associated with diaphragm use (versus pill use, alone or with condoms). In addition, lower condom use self-efficacy was significantly associated with diaphragm use (versus condom use, alone or with pill). Lack of motivation to avoid HIV/STIs was significantly associated with using the diaphragm versus condoms (only). These results have important implications for future research, interventions, counseling strategies for providers, and product development. Our findings suggest that if the diaphragm protects against HIV, it could be a desirable option for some women.

  17. Developmental plasticity of phrenic motoneuron and diaphragm properties with the inception of inspiratory drive transmission in utero.

    Science.gov (United States)

    Greer, John J; Martin-Caraballo, Miguel

    2017-01-01

    The review outlines data consistent with the hypothesis that inspiratory drive transmission that generates fetal breathing movements (FBMs) is essential for the developmental plasticity of phrenic motoneurons (PMNs) and diaphragm musculature prior to birth. A systematic examination during the perinatal period demonstrated a very marked transformation of PMN and diaphragm properties coinciding with the onset and strengthening of inspiratory drive and FBMs in utero. This included studies of age-dependent changes of: i) morphology, neuronal coupling, passive and electrophysiological properties of PMNs; ii) rhythmic inspiratory activity in vitro; iii) FBMs generated in vivo detected by ultrasonography; iv) contractile and end-plate potential properties of diaphragm musculature. We also propose how the hypothesis can be further evaluated with studies of perinatal hypoglossal motoneuron-tongue musculature and the use of Dbx1 null mice that provide an experimental model lacking descending inspiratory drive transmission in utero. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Robust control of dielectric elastomer diaphragm actuator for human pulse signal tracking

    Science.gov (United States)

    Ye, Zhihang; Chen, Zheng; Asmatulu, Ramazan; Chan, Hoyin

    2017-08-01

    Human pulse signal tracking is an emerging technology that is needed in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is needed for tracking human pulse signal. Dielectric elastomer (DE) is one type of soft actuating that has great potential in human pulse signal tracking. In this paper, a DE diaphragm actuator was designed and fabricated to track human pulse pressure signal. A physics-based and control-oriented model has been developed to capture the dynamic behavior of DE diaphragm actuator. Using the physical model, an H-infinity robust control was designed for the actuator to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track a multi-frequency signal, which verified the tracking capability and robustness of the control system. In the human pulse signal tracking test, a human pulse signal was measured at the City University of Hong Kong and then was tracked using DE actuator at Wichita State University in the US. Experimental results have verified that the DE actuator with its robust control is capable of tracking human pulse signal.

  19. Laterally Driven Resonant Pressure Sensor with Etched Silicon Dual Diaphragms and Combined Beams

    Directory of Open Access Journals (Sweden)

    Xiaohui Du

    2016-01-01

    Full Text Available A novel structure of the resonant pressure sensor is presented in this paper, which tactfully employs intercoupling between dual pressure-sensing diaphragms and a laterally driven resonant strain gauge. After the resonant pressure sensor principle is introduced, the coupling mechanism of the diaphragms and resonator is analyzed and the frequency equation of the resonator based on the triangle geometry theory is developed for this new coupling structure. The finite element (FE simulation results match the theoretical analysis over the full scale of the device. This pressure sensor was first fabricated by dry/wet etching and thermal silicon bonding, followed by vacuum-packaging using anodic bonding technology. The test maximum error of the fabricated sensor is 0.0310%F.S. (full scale in the range of 30 to 190 kPa, its pressure sensitivity is negative and exceeding 8 Hz/kPa, and its Q-factor reaches 20,000 after wafer vacuum-packaging. A novel resonant pressure sensor with high accuracy is presented in this paper.

  20. The influence of nerve section on the metabolism of polyamines in rat diaphragm muscle.

    Science.gov (United States)

    Hopkins, D; Manchester, K L

    1981-01-01

    Concentrations of spermidine, spermine and putrescine have been measured in rat diaphragm muscle after unilateral nerve section. The concentration of putrescine increased approx. 10-fold 2 days after nerve section, that of spermidine about 3-fold by day 3, whereas an increase in the concentration of spermine was only observed after 7-10 days. It was not possible to show enhanced uptake of either exogenous putrescine or spermidine by the isolated tissue during the hypertrophy. Consistent with the accumulation of putrescine, activity of ornithine decarboxylase increased within 1 day of nerve section, was maximally elevated by the second day and then declined. Synthesis of spermidine from [14C]putrescine and either methionine or S-adenosylmethionine bt diaphragm cytosol rose within 1 day of nerve section, but by day 3 had returned to normal or below normal values. Activity of adenosylmethionine decarboxylase similarly increased within 1 day of nerve section, but by day 3 had declined to below normal values. Activity of methionine adenosyltransferase was elevated throughout the period studied. The concentration of S-adenosylmethionine was likewise enhanced during hypertrophy. Administration of methylglyoxal bis(guanylhydrazone) produced a marked increase in adenosylmethionine decarboxylase activity and a large increase in putrescine concentration, but did not prevent the rise in spermidine concentration produced by denervation. Possible regulatory mechanisms of polyamine metabolism consistent with the observations are discussed. PMID:7316998

  1. Vibrational mode and sound radiation of electrostatic speakers using circular and annular diaphragms

    Science.gov (United States)

    Huang, Yu-Hsi; Chiang, Hsin-Yuan

    2016-06-01

    This study modeled two diaphragms comprising a pair of indium tin oxide (ITO) transparent plates sandwiching a vibrating diaphragm to create circular (30 mm radius) and annular (30 mm outer and 3 mm inner radius) push-pull electrostatic speakers. We then measured the displacement amplitudes and mode shapes produced by the devices. Vibration characteristics were used to predict sound pressure levels (SPLs) using the lumped parameter method (LPM) and distributed parameter method (DPM). The two measurement results obtained using a laser system were compared to the SPLs obtained using traditional acoustic measurement (AM) from 20 Hz to 20 kHz in order to verify our predictions. When using LPM and DPM, the SPL prediction results in the first three symmetric modes were in good agreement with the AM results. Under the assumption of linear operations, the DPM and amplitude-fluctuation electronic speckle pattern interferometry (ESPI) techniques proved effective in determining the visualization of mode shape (0,1)-(0,3). The use of ITO plates is a practical technique for the prediction of SPL, as well as measurement of mode shapes. The four evaluation methods, i.e. LPM, DPM, ESPI and AM, present a high degree of consistency with regard to vibrational mode and sound radiation characteristics.

  2. Lipid intermediates in membrane fusion: formation, structure, and decay of hemifusion diaphragm.

    Science.gov (United States)

    Kozlovsky, Yonathan; Chernomordik, Leonid V; Kozlov, Michael M

    2002-11-01

    Lipid bilayer fusion is thought to involve formation of a local hemifusion connection, referred to as a fusion stalk. The subsequent fusion stages leading to the opening of a fusion pore remain unknown. The earliest fusion pore could represent a bilayer connection between the membranes and could be formed directly from the stalk. Alternatively, fusion pore can form in a single bilayer, referred to as hemifusion diaphragm (HD), generated by stalk expansion. To analyze the plausibility of stalk expansion, we studied the pathway of hemifusion theoretically, using a recently developed elastic model. We show that the stalk has a tendency to expand into an HD for lipids with sufficiently negative spontaneous splay, (~)J(s)action of an external force pulling the diaphragm rim apart. We calculate the dependence of the HD radius on this force. To address the mechanism of fusion pore formation, we analyze the distribution of the lateral tension emerging in the HD due to the establishment of lateral equilibrium between the deformed and relaxed portions of lipid monolayers. We show that this tension concentrates along the HD rim and reaches high values sufficient to rupture the bilayer and form the fusion pore. Our analysis supports the hypothesis that transition from a hemifusion to a fusion pore involves radial expansion of the stalk.

  3. Contribution of oxidative stress to pathology in diaphragm and limb muscles with Duchenne muscular dystrophy.

    Science.gov (United States)

    Kim, Jong-Hee; Kwak, Hyo-Bum; Thompson, LaDora V; Lawler, John M

    2013-02-01

    Duchenne muscular dystrophy (DMD) is a degenerative skeletal muscle disease that makes walking and breathing difficult. DMD is caused by an X-linked (Xp21) mutation in the dystrophin gene. Dystrophin is a scaffolding protein located in the sarcolemmal cytoskeleton, important in maintaining structural integrity and regulating muscle cell (muscle fiber) growth and repair. Dystrophin deficiency in mouse models (e.g., mdx mouse) destabilizes the interface between muscle fibers and the extracellular matrix, resulting in profound damage, inflammation, and weakness in diaphragm and limb muscles. While the link between dystrophin deficiency with inflammation and pathology is multi-factorial, elevated oxidative stress has been proposed as a central mediator. Unfortunately, the use of non-specific antioxidant scavengers in mouse and human studies has led to inconsistent results, obscuring our understanding of the importance of redox signaling in pathology of muscular dystrophy. However, recent studies with more mechanistic approaches in mdx mice suggest that NAD(P)H oxidase and nuclear factor-kappaB are important in amplifying dystrophin-deficient muscle pathology. Therefore, more targeted antioxidant therapeutics may ameliorate damage and weakness in human population, thus promoting better muscle function and quality of life. This review will focus upon the pathobiology of dystrophin deficiency in diaphragm and limb muscle primarily in mouse models, with a rationale for development of targeted therapeutic antioxidants in DMD patients.

  4. An Accurate Study on Capacitive Microphone with Circular Diaphragm Using a Higher Order Elasticity Theory

    Directory of Open Access Journals (Sweden)

    Shakiba Dowlati

    Full Text Available Abstract This study has been undertaken to investigate the mechanical behavior of the capacitive microphone with clamped circular diaphragm using modified couple stress theory in comparison to the classical one. Presence of the length scale parameter in modified couple stress theory provides the means to evaluate the size effect on the microphone mechanical behavior. Investigating Pull-in phenomenon and dynamic behavior of the microphone are the matters provided due to the application of a step DC voltage. Also the effects of different air damping coefficients on dynamic pull-in voltage and pull-in time have been studied. The output level or sensitivity of the microphone has been studied by investigating the frequency response in term of magnitude for different length scale parameters to figure out how the length scale parameter affects on the sensitivity of the capacitive microphone. To achieve these ends, the nonlinear differential equation of the circular diaphragm has been extracted using Kirchhoff thin plate theory. Then, a Step-by-Step Linearization Method (SSLM has been used to escape from the nonlinearity of the differential equation. Afterwards, Galerkin-based reduced-order model has been applied to solve the obtained equation.

  5. Crura sign: differentiation between traumatic rupture of the diaphragm and nontraumatic diaphragmatic elevation on CT

    International Nuclear Information System (INIS)

    Kim, Sung Jin; Han, Hae Ja; Kim, Wang Jung; Youk, Yong Soo; Han, Gi Seok; Cha, Sang Hoon; Park, Kil Sun; Kim, Dae Young

    1997-01-01

    To evaluate whether in patients with diffuse evaluation of a hemidiaphragm on chest radiographs, the apparence of the crura on CT might be helpful in differentiating between traumatic rupture of the diaphragm (TRD) and nontraumatic causes such as diaphragmatic palsy or diffuse diaphragmatic eventration. Among patients with diffuse elevations of a hemidiaphragm on chest radiograph, 27 who had patients undergone CT scans were retrospectively reviewed. Twelve patients had surgically proven TRD, and 15 had nontraumatic elevation of a hemidiaphragm such as diaphragmatic palsy or diffuse diaphragmatic eventration. Under the hypothesis that the affected crus is markedly thinner than the normal side in nontraumatic elevation but is normal in TRD ('crura sign', we optically assessed without measurement the thickness of both crura. In all patients with TRD, the thickness of the affected crus was similar to that of the contralateral side. In all patients with nontraumatic causes, however, the crus of the elevated hemidiaphragm was markedly thinner than that of the normal side. The 'crura sign' may be useful additional CT finding of traumatic rupture the diaphragm

  6. Studies on the uptake of 14C-neostigmine in the isolated rat diaphragm

    International Nuclear Information System (INIS)

    Helleberg, L.

    1976-01-01

    The uptake process of 14 C-neostigmine in striated muscles was studied using the isolated rat diaphragm. Hemidiaphragms were incubated with 3x10 -7 M 14 C-neostigmine at 37deg in Krebs-Ringer solution containing 11 mM glucose and aerated with oxygen:carbon dioxide (95:5 v/v %). The uptake, which is expressed as the muscle-to-medium concentration ratio, was 1.41, after 3 hours, after which the rate of uptake diminished and became equal to that of inulin. The uptake which showed partial saturation, was decreased by some tertiary and quarternary amines, metabolic inhibitors, potassium and in an atmosphere of nitrogen. Neostigmine accumulated in all parts of the muscle without preference for the end plate zone. The half-time for the efflux was about 30 min. The phrenic nerve-diaphragm preparation became desensitized to the effect of 3x10 -7 M neostigmine after 2-3 hours. It is suggested that the uptake of neostigmine is mediated via a specialized carrier transport system. (author)

  7. Experimental validation of the tuneable diaphragm effect in modern acoustic stethoscopes.

    Science.gov (United States)

    Nowak, Karolina M; Nowak, Lukasz J

    2017-09-01

    The force with which the diaphragm chestpiece of a stethoscope is pressed against the body of a patient during an auscultation examination introduces the initial stress and deformation to the diaphragm and the underlying tissues, thus altering the acoustic parameters of the sound transmission path. If the examination is performed by an experienced physician, he will intuitively adjust the amount of the force in order to achieve the optimal sound quality. However, in case of becoming increasingly popular auto-diagnosis and telemedicine auscultation devices with no such feedback mechanisms, the question arises regarding the influence of the possible force mismatch on the parameters of the recorded signal. The present study describes the results of the experimental investigations on the relation between pressure applied to the chestpiece of a stethoscope and parameters of the transmitted bioacoustic signals. The experiments were carried out using various stethoscopes connected to a force measurement system, which allowed to maintain fixed pressure during auscultation examinations. The signals were recorded during examinations of different volunteers, at various auscultation sites. The obtained results reveal strong individual and auscultation-site variability. It is concluded that the underlying tissue deformation is the primary factor that alters the parameters of the recorded signals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  8. [Diaphragm pacing for the ventilatory support of the quadriplegic patients with respiratory paralysis].

    Science.gov (United States)

    Cheng, H; Wang, L S; Pan, H C; Shoung, H M; Lee, L S

    1992-02-01

    Electrical stimulation of the phrenic nerve to pace the diaphragm in patients with chronic ventilatory insufficiency has been an established therapeutic modality since William W.L. Glenn first described using radiofrequency signals in 1978 to stimulate the phrenic nerves. Before this event, patients who were ventilator-dependent and thus bedridden because of respiratory paralysis associated with quadriplegia usually anticipated little chance for physical or psychosocial rehabilitation. Two cases of C1-C2 subluxtion with cord injury and chronic ventilatory insufficiency were implanted at VGH-Taipei with diaphragm pacemaker in 1988. Postoperative phrenic nerve stimulation was given according to individual training schedule. One case with total phrenic paralysis received bilateral phrenic nerve stimulation and became weaned from the ventilator 6 months later. The other case with partially active ventilatory function received unilateral phrenic nerve stimulation to compensate the ventilation. However, its final outcome still showed the necessity of a bilateral mode to achieve adequate ventilation irrespective of strenuous training for 2 years.

  9. Sensory and motor innervation of the crural diaphragm by the vagus nerves.

    Science.gov (United States)

    Young, Richard L; Page, Amanda J; Cooper, Nicole J; Frisby, Claudine L; Blackshaw, L Ashley

    2010-03-01

    During gastroesophageal reflux, transient lower esophageal sphincter relaxation and crural diaphragm (CD) inhibition occur concomitantly. Modifying vagus nerve control of transient lower esophageal sphincter relaxation is a major focus of development of therapeutics for gastroesophageal reflux disease, but neural mechanisms that coordinate the CD are poorly understood. Nerve tracing and immunolabeling were used to assess innervation of the diaphragm and lower esophageal sphincter in ferrets. Mechanosensory responses of vagal afferents in the CD and electromyography responses of the CD were recorded in novel in vitro preparations and in vivo. Retrograde tracing revealed a unique population of vagal CD sensory neurons in nodose ganglia and CD motor neurons in brainstem vagal nuclei. Anterograde tracing revealed specialized vagal endings in the CD and phrenoesophageal ligament-sites of vagal afferent mechanosensitivity recorded in vitro. Spontaneous electromyography activity persisted in the CD following bilateral phrenicotomy in vivo, while vagus nerve stimulation evoked electromyography responses in the CD in vitro and in vivo. We conclude that vagal sensory and motor neurons functionally innervate the CD and phrenoesophageal ligament. CD vagal afferents show mechanosensitivity to distortion of the gastroesophageal junction, while vagal motor neurons innervate both CD and distal esophagus and may represent a common substrate for motor control of the reflux barrier. Copyright 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.

  10. Anatomy of pudendal nerve at urogenital diaphragm--new critical site for nerve entrapment.

    Science.gov (United States)

    Hruby, Stephan; Ebmer, Johannes; Dellon, A Lee; Aszmann, Oskar C

    2005-11-01

    To investigate the relations of the pudendal nerve in this complex anatomic region and determine possible entrapment sites that are accessible for surgical decompression. Entrapment neuropathies of the pudendal nerve are an uncommon and, therefore, often overlooked or misdiagnosed clinical entity. The detailed relations of this nerve as it exits the pelvis through the urogenital diaphragm and enters the mobile part of the penis have not yet been studied. Detailed anatomic dissections were performed in 10 formalin preserved hemipelves under 3.5x loupe magnification. The pudendal nerve was dissected from the entrance into the Alcock canal to the dorsum of the penis. The branching pattern of the nerve and its topographic relationship were recorded and photographs taken. The anatomic dissections revealed that the pudendal nerve passes through a tight osteofibrotic canal just distal to the urogenital diaphragm at the entrance to the base of the penis. This canal is, in part, formed by the inferior ramus of the pubic bone, the suspensory ligament of the penis, and the ischiocavernous body. In two specimens, a fusiform pseudoneuromatous thickening was found. The pudendal nerve is susceptible to compression at the passage from the Alcock canal to the dorsum of the penis. Individuals exposed to repetitive mechanical irritation in this region are especially endangered. Diabetic patients with peripheral neuropathy can have additional compression neuropathy with decreased penile sensibility and will benefit from decompression of the pudendal nerve.

  11. An electrostatic scanning micromirror with diaphragm mirror plate and diamond-shaped reinforcement frame

    Science.gov (United States)

    Ji, Chang-Hyeon; Choi, Moongoo; Kim, Sang-Cheon; Lee, See-Hyung; Kim, Seong-Hyok; Yee, Youngjoo; Bu, Jong-Uk

    2006-05-01

    We present the design, fabrication and measurement results of a comb-driven electrostatic scanning micromirror. Instead of a conventional micromirror having uniform thickness across the entire reflective surface, a diaphragm mirror plate supported by an array of diamond-shaped frame structures is fabricated monolithically. The fabrication process is a simple sequence of silicon deep etch processes on both sides of the silicon-on-insulator (SOI) substrate without the substrate bonding process. The micromirror is fabricated on the device layer of the substrate. The mirror plate undergoes a rotational motion by an electrostatic force between the movable comb electrodes connected to the micromirror and stationary comb electrode formed on the handle wafer. A scanning micromirror with a 10 µm thick diaphragm mirror plate, having a planar dimension of 1.5 × 1.5 mm2, supported by an array of 110 µm thick rhombic support frames, was fabricated and tested. A mechanical deflection angle of 8.5° at a resonance frequency of 19.55 kHz and a pressure of 7 mTorr was obtained. A prototype of the raster scanning laser projection display system was developed using the fabricated micromirror as the horizontal scanner and a galvanomirror as the vertical scanner, respectively.

  12. Genetic specification of left–right asymmetry in the diaphragm muscles and their motor innervation

    Science.gov (United States)

    Charoy, Camille; Dinvaut, Sarah; Chaix, Yohan; Morlé, Laurette; Sanyas, Isabelle; Bozon, Muriel; Kindbeiter, Karine; Durand, Bénédicte; Skidmore, Jennifer M; De Groef, Lies; Seki, Motoaki; Moons, Lieve; Ruhrberg, Christiana; Martin, James F; Martin, Donna M; Falk, Julien; Castellani, Valerie

    2017-01-01

    The diaphragm muscle is essential for breathing in mammals. Its asymmetric elevation during contraction correlates with morphological features suggestive of inherent left–right (L/R) asymmetry. Whether this asymmetry is due to L versus R differences in the muscle or in the phrenic nerve activity is unknown. Here, we have combined the analysis of genetically modified mouse models with transcriptomic analysis to show that both the diaphragm muscle and phrenic nerves have asymmetries, which can be established independently of each other during early embryogenesis in pathway instructed by Nodal, a morphogen that also conveys asymmetry in other organs. We further found that phrenic motoneurons receive an early L/R genetic imprint, with L versus R differences both in Slit/Robo signaling and MMP2 activity and in the contribution of both pathways to establish phrenic nerve asymmetry. Our study therefore demonstrates L–R imprinting of spinal motoneurons and describes how L/R modulation of axon guidance signaling helps to match neural circuit formation to organ asymmetry. DOI: http://dx.doi.org/10.7554/eLife.18481.001 PMID:28639940

  13. Evaluation of COPD's diaphragm motion extracted from 4D-MRI

    Science.gov (United States)

    Swastika, Windra; Masuda, Yoshitada; Kawata, Naoko; Matsumoto, Koji; Suzuki, Toshio; Iesato, Ken; Tada, Yuji; Sugiura, Toshihiko; Tanabe, Nobuhiro; Tatsumi, Koichiro; Ohnishi, Takashi; Haneishi, Hideaki

    2015-03-01

    We have developed a method called intersection profile method to construct a 4D-MRI (3D+time) from time-series of 2D-MRI. The basic idea is to find the best matching of the intersection profile from the time series of 2D-MRI in sagittal plane (navigator slice) and time series of 2D-MRI in coronal plane (data slice). In this study, we use 4D-MRI to semiautomatically extract the right diaphragm motion of 16 subjects (8 healthy subjects and 8 COPD patients). The diaphragm motion is then evaluated quantitatively by calculating the displacement of each subjects and normalized it. We also generate phase-length map to view and locate paradoxical motion of the COPD patients. The quantitative results of the normalized displacement shows that COPD patients tend to have smaller displacement compared to healthy subjects. The average normalized displacement of total 8 COPD patients is 9.4mm and the average of normalized displacement of 8 healthy volunteers is 15.3mm. The generated phase-length maps show that not all of the COPD patients have paradoxical motion, however if it has paradoxical motion, the phase-length map is able to locate where does it occur.

  14. Degeneration of Phrenic Motor Neurons Induces Long-Term Diaphragm Deficits following Mid-Cervical Spinal Contusion in Mice

    Science.gov (United States)

    Nicaise, Charles; Putatunda, Rajarshi; Hala, Tamara J.; Regan, Kathleen A.; Frank, David M.; Brion, Jean-Pierre; Leroy, Karelle; Pochet, Roland; Wright, Megan C.

    2012-01-01

    Abstract A primary cause of morbidity and mortality following cervical spinal cord injury (SCI) is respiratory compromise, regardless of the level of trauma. In particular, SCI at mid-cervical regions targets degeneration of both descending bulbospinal respiratory axons and cell bodies of phrenic motor neurons, resulting in deficits in the function of the diaphragm, the primary muscle of inspiration. Contusion-type trauma to the cervical spinal cord is one of the most common forms of human SCI; however, few studies have evaluated mid-cervical contusion in animal models or characterized consequent histopathological and functional effects of degeneration of phrenic motor neuron–diaphragm circuitry. We have generated a mouse model of cervical contusion SCI that unilaterally targets both C4 and C5 levels, the location of the phrenic motor neuron pool, and have examined histological and functional outcomes for up to 6 weeks post-injury. We report that phrenic motor neuron loss in cervical spinal cord, phrenic nerve axonal degeneration, and denervation at diaphragm neuromuscular junctions (NMJ) resulted in compromised ipsilateral diaphragm function, as demonstrated by persistent reduction in diaphragm compound muscle action potential amplitudes following phrenic nerve stimulation and abnormalities in spontaneous diaphragm electromyography (EMG) recordings. This injury paradigm is reproducible, does not require ventilatory assistance, and provides proof-of-principle that generation of unilateral cervical contusion is a feasible strategy for modeling diaphragmatic/respiratory deficits in mice. This study and its accompanying analyses pave the way for using transgenic mouse technology to explore the function of specific genes in the pathophysiology of phrenic motor neuron degeneration and respiratory dysfunction following cervical SCI. PMID:23176637

  15. Autophagy-associated atrophy and metabolic remodeling of the mouse diaphragm after short-term intermittent hypoxia.

    Directory of Open Access Journals (Sweden)

    Christian Giordano

    Full Text Available Short-term intermittent hypoxia (IH is common in patients with acute respiratory disorders. Although prolonged exposure to hypoxia induces atrophy and increased fatigability of skeletal muscle, the response to short-term IH is less well known. We hypothesized that the diaphragm and limb muscles would adapt differently to short-term IH given that hypoxia stimulates ventilation and triggers a superimposed exercise stimulus in the diaphragm.We determined the structural, metabolic, and contractile properties of the mouse diaphragm after 4 days of IH (8 hours per day, 30 episodes per hour to a FiO2 nadir=6%, and compared responses in the diaphragm to a commonly studied reference limb muscle, the tibialis anterior. Outcome measures included muscle fiber size, assays of muscle proteolysis (calpain, ubiquitin-proteasome, and autophagy pathways, markers of oxidative stress and mitochondrial function, quantification of intramyocellular lipid and lipid metabolism genes, type I myosin heavy chain (MyHC expression, and in vitro contractile properties.After 4 days of IH, the diaphragm alone demonstrated significant atrophy (30% decrease of myofiber size together with increased LC3B-II protein (2.4-fold and mRNA markers of the autophagy pathway (LC3B, Gabarapl1, Bnip3, whereas active calpain and E3 ubiquitin ligases (MuRF1, atrogin-1 were unaffected in both muscles. Succinate dehydrogenase activity was significantly reduced by IH in both muscles. However, only the diaphragm exhibited increased intramyocellular lipid droplets (2.5-fold after IH, along with upregulation of genes linked to activated lipid metabolism. In addition, although the diaphragm showed evidence for acute fatigue immediately following IH, it underwent an adaptive fiber type switch toward slow type I MyHC-expressing fibers, associated with greater intrinsic endurance of the muscle during repetitive stimulation in vitro.Short-term IH induces preferential atrophy in the mouse diaphragm

  16. Evaluating the effect of pressure on the diaphragm micro- electro-mechanical thickness and the amount of shift in medical applications

    Directory of Open Access Journals (Sweden)

    Nazli Zargarpour

    2017-04-01

    Full Text Available In this paper, the influence of design parameters on the sensitive microphone diaphragm for use in implantable medical applications is presented. The different parameters such as diaphragm shape, size, thickness and different applied pressures on the diaphragm has been considered. The effect of changes in these parameters on the displacement and stress in a variety of shapes of diaphragm is discussed. In order to design the optimal shape of the proposed diaphragm for the considered parameters, it has been simulated and analyzed in software COMSOL. According to the parameters, the diaphragm shapes of square, rectangular and oval with respect to the intended user, average central displacement in human hearing frequency range 20Hz-20KHz are nm 5. 5, nm2. 6, and nm 130 respectively . According to the results of the simulations, the oval-shaped diaphragm that has been studies in this paper, the possibility of implanted medical applications, performance is optimal than other shapes. In addition, the piezoelectric material is PZT which used in the design of the diaphragm.

  17. Fatigue strength of the joint between diaphragms and longitudinal ribs in box section girders; Hako danmen keta no diaphragm to shita flange tateribu no kosabu no hiro kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Miki, C.; Shiozaki, M.; Takeishi, K. [Tokyo Institute of Technology, Tokyo (Japan). Faculty of Engineering; Ohashi, H. [Honshu-Shikoku Bridge Authority, Tokyo (Japan)

    1997-04-21

    Discussions were given on crossing joints of diaphragms on hanger fixing sections and U-ribs on lower flanges in reinforcing box girders of a suspension bridge, as to their local stress generating behavior and effects of cope holes on fatigue strength. The test pieces have dimensions and shapes modeling the crossing joints, and the steel materials are SM490YA for upper and lower flanges and webs, and SS400 for U-ribs. The loading test was performed with four-point bending and at loading amplitudes of 30 to 45 tf. Furthermore, stress analysis was conducted by using the finite element method. The following conclusions were obtained as a result: local stress at cope hole tips decreases and fatigue strength increases with the smaller the cope hole diameter; when the cope holes are back-filled completely, deformation is concentrated on welds of the U-ribs and the flanges, generating high local stress; this reduces significantly the fatigue strength of details having no cope holes; and no particular differences are found on effects of boxing of the cope hole tips on the fatigue strength. 7 refs., 10 figs., 3 tabs.

  18. Therapeutic effects of diaphragmatic plication for acquired unilateral non-malignant diaphragm paralysis in twenty patients

    Directory of Open Access Journals (Sweden)

    Reza Bagheri

    2013-12-01

    Full Text Available Background: Acquired paralysis of the diaphragm is a condition caused by trauma, surgical injuries, (lung cancer surgery, esophageal surgery, cardiac surgery, thoracic surgery, and is sometimes of an unknown etiology. It can lead to dyspnea and can affect ventilatory function and patients activity. Diaphragmatic plication is a treatment method which decreases inconsistent function of diaphragm. The aim of this study is to evaluate the outcome of diaphragmatic plication in patients with acquired unilateral non-malignant diaphragmatic paralysis. Methods: From 1991 to 2011, 20 patients with acquired unilateral diaphragmatic paralysis who underwent surgery enrolled in our study in Ghaem Hospital Mashhad University of Medical Science. Patients were evaluated in terms of age, sex, BMI, clinical symptoms, dyspnea score (DS, etiology of paralysis, diagnostic methods, respiratory function tests and complication of surgery. Some tests including dyspnea score were carried out again six months after surgery. We evaluated patients with SPSS version 11.5 and Paired t-test or nonparametric equivalent. Results: Twenty patients enrolled in our study. 14 were male and 6 were female. The mean age was 58 years and the average time interval between diagnosis to surgical treatment was 38.3 months. Acquired diaphragmatic paralysis was mostly caused by trauma (in 11 patients and almost occurred on the left side (in 15 patients. Diagnostic methods included chest x-ray, CT scan, ultrasonography and sniff. Test prior to surgery the average FVC was 41.4±7 percent and the average FEV1 was 52.4±6 percent and after surgery they were 80.1±8.6 percent and 74.4±1 percent respectively. The average increase in FEV1 and FVC 63.4±4, 61.1±7.8. Performing surgery also leads to a noticeable improvement in dyspnea score in our study. Conclusion: In patients with acquired unilateral non-malignant diaphragm paralysis diaphragmatic plication is highly recommended due to the

  19. Mycobacterium avium subsp. avium in lymph nodes and diaphragms of pigs from one infected herd in the Czech Republic.

    Science.gov (United States)

    Kriz, Petr; Kaevska, Marija; Slana, Iva; Bartejsova, Iva; Pavlik, Ivo

    2014-01-01

    This study was performed on 40 finished pigs from one herd naturally infected with Mycobacterium avium subsp. avium. The aim was to investigate the presence and amount of M. a. avium in samples of lymph nodes and diaphragm tissues collected during routine postmortem inspection using the triplex quantitative real time PCR (qPCR) method. We collected, in total, 107 samples: various lymph nodes affected by gross tuberculosis (TB)-like lesions from 17 pig carcasses, as well as samples of head and mesenteric lymph nodes from 23 carcasses without TB-like lesions. Samples of diaphragm tissues were collected from all carcasses. M. a. avium was detected in one or more tissue samples collected from half of the slaughtered pigs tested. Samples of diaphragm tissues of three pigs with detected TB-like lesions contained M. a. avium (10(2) to 10(3) cells per g of sample); the organism was not detected in diaphragm tissues from pigs without TB-like lesions. The qPCR method may be useful for quantification of M. a. avium in pigs for the purposes of foodborne risk assessment.

  20. Effects of Processing Parameters on the Forming Quality of C-Shaped Thermosetting Composite Laminates in Hot Diaphragm Forming Process

    Science.gov (United States)

    Bian, X. X.; Gu, Y. Z.; Sun, J.; Li, M.; Liu, W. P.; Zhang, Z. G.

    2013-10-01

    In this study, the effects of processing temperature and vacuum applying rate on the forming quality of C-shaped carbon fiber reinforced epoxy resin matrix composite laminates during hot diaphragm forming process were investigated. C-shaped prepreg preforms were produced using a home-made hot diaphragm forming equipment. The thickness variations of the preforms and the manufacturing defects after diaphragm forming process, including fiber wrinkling and voids, were evaluated to understand the forming mechanism. Furthermore, both interlaminar slipping friction and compaction behavior of the prepreg stacks were experimentally analyzed for showing the importance of the processing parameters. In addition, autoclave processing was used to cure the C-shaped preforms to investigate the changes of the defects before and after cure process. The results show that the C-shaped prepreg preforms with good forming quality can be achieved through increasing processing temperature and reducing vacuum applying rate, which obviously promote prepreg interlaminar slipping process. The process temperature and forming rate in hot diaphragm forming process strongly influence prepreg interply frictional force, and the maximum interlaminar frictional force can be taken as a key parameter for processing parameter optimization. Autoclave process is effective in eliminating voids in the preforms and can alleviate fiber wrinkles to a certain extent.

  1. In patients with a tumour invading the phrenic nerve does prophylactic diaphragm plication improve postoperative lung function?

    Science.gov (United States)

    Beattie, Gwyn W; Dunn, William G; Asif, Mohammed

    2016-09-01

    A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'In patients with tumours involving the phrenic nerve, does prophylactic diaphragm plication improve lung function following tumour resection?' Using the reported search, 258 papers were found of which 6 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Three case reports and one case series represent 37 patients in the literature along with two relevant animal studies. Patients treated with prophylactic plication at the time of injury or sacrifice of the phrenic nerve had reduced radiological evidence of diaphragm paralysis, lower reported shortness of breath and reduced requirement for ventilatory support. In patients with prophylactic diaphragm plication and a concurrent pulmonary resection, the predicted postoperative lung function correlated closely with the postoperative measured FEV1, FVC and gas transfer. The postoperative measured FEV1 was reported as 86-98%, the FVC 82-89% and gas transfer 97% of the predicted values. Two animal models investigate the mechanics of respiration, spirometry and gas exchange following diaphragmatic plication. A randomized control study in four dogs measured a 50% reduction in tidal volume and respiratory rate, a 40% decrease in arterial PO2 and a 43% increase in arterial CO2 when the phrenic nerve was crushed in animals with a pneumonectomy but without prophylactic diaphragm plication. A further randomized control animal study with 28 dogs found that plicating the diaphragm after unilateral phrenic nerve transection resulted in a significant increase in tidal volume and lung compliance and a significant decrease in respiratory frequency and the work of breathing. Prophylactic diaphragm plication may preserve lung function, reduce the risk of

  2. Development of the superconducting gravimeter using a new type of diaphragm

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, H., E-mail: ikeda@bk.tsukuba.ac.jp [Research Facility Center for Science and Technology, Cryogenics Division, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Aoyama, Y.; Hayakawa, H.; Doi, K.; Shibuya, K. [National Institute of Polar Research, Midori-Machi, Tchikawa-shi, Tokyo 190-8518 (Japan)

    2011-11-15

    During the period from December 2009 to February 2010, a new superconducting gravimeter with a cryocooler was installed to replace the former one at Syowa Station on the Antarctica. It has a high sensitivity of one nano-gal enabling measurement inside the Earth for the Global Geodynamics Project (GGP network). A new type of diaphragm was confirmed to well isolate the vibration from refrigerator cold-head and to prevent the solid air contamination perfectly. The Dewar refrigeration system consists of a newly designed Dewar interfaced with a cryocooler capable of obtaining temperatures below the vaporization point of liquid helium. The system is based on the Coolpower 0.1 W, 4.2 K cryocooler manufactured by Sumitomo Heavy Industries, Ltd. Real time remote monitoring system from Japan was also established. The recent large earthquake in the Republic of Chile was observed at Syowa Station with the superconducting gravimeter.

  3. Development of the superconducting gravimeter using a new type of diaphragm

    International Nuclear Information System (INIS)

    Ikeda, H.; Aoyama, Y.; Hayakawa, H.; Doi, K.; Shibuya, K.

    2011-01-01

    During the period from December 2009 to February 2010, a new superconducting gravimeter with a cryocooler was installed to replace the former one at Syowa Station on the Antarctica. It has a high sensitivity of one nano-gal enabling measurement inside the Earth for the Global Geodynamics Project (GGP network). A new type of diaphragm was confirmed to well isolate the vibration from refrigerator cold-head and to prevent the solid air contamination perfectly. The Dewar refrigeration system consists of a newly designed Dewar interfaced with a cryocooler capable of obtaining temperatures below the vaporization point of liquid helium. The system is based on the Coolpower 0.1 W, 4.2 K cryocooler manufactured by Sumitomo Heavy Industries, Ltd. Real time remote monitoring system from Japan was also established. The recent large earthquake in the Republic of Chile was observed at Syowa Station with the superconducting gravimeter.

  4. Extra Lobes of Liver and Congenital Anomalies of Diaphragm in Children

    Directory of Open Access Journals (Sweden)

    I.P. Zhurylo

    2014-09-01

    Full Text Available The literature data on hepatic congenital anomalies in children are summarized in this article. Three clinical observations of transposition of extra lobe of the liver (ELL into the thoracic cavity in children were analyzed. The true diaphragmatic hernia was found in all cases. Clinical manifestations of this disease depend on the severity of the compression of mediastinum organs. Indications for surgical correction were determined individually. ELL move into the abdominal cavity, excision of the hernia sac and alloplasty of the diaphragmatic defect were performed for one patient. Possible mechanisms for the formation of these complex congenital malformations were discussed based on the comparison of clinical data with the stages of embryogenesis liver, diaphragm and heart.

  5. Modulation of the sound press level by the treatment of polymer diaphragms through ion implantation method

    International Nuclear Information System (INIS)

    Yeo, Sunmog; Park, Jaewon; Lee, Hojae

    2010-01-01

    We present two different surface modification treatments, an ion implantation, and an ion beam mixing, and show that the surface modifications caused by these treatments are useful tools to modulate the sound press level. The ion implantations on various polymer diaphragms cause an increase in the resonant frequency so that the sound press level is lowered at low frequencies. On the contrary, a Cu or Fe 2 O 3 coating by using an ion beam mixing method causes a decrease in the resonant frequency, resulting in a high sound press level at low frequencies. We discuss the physical reasons for the change in the sound press level due to the ion-implantation methods.

  6. Diaphragm metering pumps for cooling silicon sensors at the CERN research center for particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Geiselhart, Marc [LEWA Pumpen AG, Reinach (Switzerland); CERN Press Office, Geneva (Switzerland)

    2016-12-15

    With approximately 9,600 magnets and a circumference of 26.659 km, the Large Hadron Collider (LHC) is the largest and most sophisticated accelerator operated by the CERN research institute. The Large Hadron Collider beauty (LHCb) experiment, the A Toroidal LHC ApparatuS (ATLAS) experiment, and the Compact Muon Solenoid (CMS) experiment are three of the four experiments currently installed at LHC. In order to achieve precise measurements, silicon detectors are built in close vicinity to the interaction point of all experiments. Carbon dioxide cooling plants cool the innermost layers of the silicon detectors down to temperatures as low as -40 C. Two diaphragm metering pumps have been used for the LHCb experiment since 2007. Two similar systems operated in redundancy guarantee from the beginning of 2015 the thermal management of the IBL sub-detector of the TALS experiment.

  7. Reduction of Cr(VI) in aqueous solution with DC diaphragm glow discharge

    International Nuclear Information System (INIS)

    Wang, Xiaoyan; Jin, Xinglong; Zhou, Minghua; Chen, Zhenhai; Deng, Kai

    2013-01-01

    This paper investigated the reduction of Cr(VI) in aqueous solution with direct current diaphragm glow discharge (DGD). The glow discharge sustained around the hole on a quartz tube which divided the electrolyte cell into two parts. The reduction efficiencies of Cr(VI) under different applied voltages, initial conductivities, hole diameters, hole numbers, initial pH values and initial concentrations were systematically studied. The results showed that the reduction efficiency of Cr(VI) increased with the increase of applied voltage, initial conductivity, hole diameter and hole number. The different initial pH values showed less effects on the reduction of Cr(VI). The reduction efficiency decreased with the increasing initial concentration. In addition, the simultaneous reduction of Cr(VI) and decolorization of acid orange (AO) with DGD were also fulfilled. Furthermore, the energy efficiency for Cr(VI) reduction with DGD was calculated and compared with those in photocatalysis and other glow discharge reactor

  8. Adaptive unstructured simulations of diaphragm rupture and perforation opening to start hypersonic air inlets

    International Nuclear Information System (INIS)

    Timofeev, E.V.; Tahir, R.B.; Voinovich, P.A.; Moelder, S.

    2004-01-01

    The concept of 'twin' grid nodes is discussed in the context of unstructured, adaptive meshes that are suitable for highly unsteady flows. The concept is applicable to internal boundary contours (within the computational domain) where the boundary conditions may need to be changed dynamically; for instance, an impermeable solid wall segment can be redefined as a fully permeable invisible boundary segment during the course of the simulation. This can be used to simulate unsteady gas flows with internal boundaries where the flow conditions may change rapidly and drastically. As a demonstration, the idea is applied to study the starting process in hypersonic air inlets by rupturing a diaphragm or by opening wall-perforations. (author)

  9. [Chronic recurrent volvulus of the colonic splenic flexure associated with the eventration of left diaphragm].

    Science.gov (United States)

    Kim, Hee Sun; Yoo, Jeong Seon; Han, Seok Joo; Park, Hyojin

    2007-01-01

    The eventration of diaphragm is usually found incidentally on chest X-ray or sometimes presented as acute gastric volvulus. However, colonic volvulus on splenic flexure area complicated by diaphragmatic eventration is extremely rare. A 25 year old man complained of upper abdominal pain for three days. He had a history of brain injury during infant period, and had epilepsy and mental retardation. Plain chest X-ray showed left diaphragmatic eventration and marked dilatation of colon on splenic flexure area which had not been changed for last three years. Barium enema showed bird beak appearance on distal colon near the splenic flexure. Colonoscopic reduction failed. After decompression with rectal and nasogastric tubes, colonic volvulus was relieved. To prevent the recurrence of volvulus, we performed segmental resection of left colon including splenic flexure area and repaired the left diaphragmatic eventration. After the operation, the patient had no further recurrent episode of volvulus although ileus persisted.

  10. Hydraulics characteristics of a diaphragm pump; Caracteristicas hidraulicas de uma moto-bomba de diafragma

    Energy Technology Data Exchange (ETDEWEB)

    Kolling, Evandro M. [Uniao Pan-Americana de Ensino (UNIPAN) Cascavel, PR (Brazil); Sampaio, Silvio C.; Coldebella, Anderson [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil); Schoenwald, Celso

    2006-07-01

    The selection of a pump model that is not the most appropriate, carts consequences as: excessive consumption of energy, overload in the motor and cavity flow occurrence with consequent decrease in the revenue and in the useful life of the pump.The work extends in the study and evaluation of a diaphragm pump, it marks SHURFLO model 2088, that now has few available data for its knowledge and employment. The measured parameters were: the height (Hm), tension (v) and the current (A), and discharge (Q). The results of the they showed that the maximum values obtained for H m, revenue (h), potency (Pot), and Q was of 19 mca, 36%, 50 W, and 0,68 m3/h, respectively. The behavior observed in the characteristic curves was exponential, lineal, and polynomial for Hm x Q, Pot x Q, h x Q, respectively. (author)

  11. Corticosteroid effects on ventilator-induced diaphragm dysfunction in anesthetized rats depend on the dose administered

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    Decramer Marc

    2010-12-01

    Full Text Available Abstract Background High dose of corticosteroids has been previously shown to protect against controlled mechanical ventilation (CMV-induced diaphragmatic dysfunction while inhibiting calpain activation. Because literature suggests that the calpain inhibiting effect of corticosteroid depends on the dose administered, we determined whether lower doses of corticosteroids would also provide protection of the diaphragm during CMV. This may be important for patients undergoing mechanical ventilation and receiving corticosteroids. Methods Rats were assigned to controls or to 24 hours of CMV while being treated at the start of mechanical ventilation with a single intramuscular administration of either saline, or 5 mg/kg (low MP or 30 mg/kg (high MP of methylprednisolone. Results Diaphragmatic force was decreased after CMV and this was exacerbated in the low MP group while high MP rescued this diaphragmatic dysfunction. Atrophy was more severe in the low MP group than after CMV while no atrophy was observed in the high MP group. A significant and similar increase in calpain activity was observed in both the low MP and CMV groups whereas the high dose prevented calpain activation. Expression of calpastatin, the endogenous inhibitor of calpain, was decreased in the CMV and low MP groups but its level was preserved to controls in the high MP group. Caspase-3 activity increased in all CMV groups but to a lesser extent in the low and high MP groups. The 20S proteasome activity was increased in CMV only. Conclusions Administration of 30 mg/kg methylprednisolone during CMV protected against CMV-induced diaphragm dysfunction while 5 mg/kg was more deleterious. The protective effect is due mainly to an inhibition of the calpain system through preservation of calpastatin levels and to a lesser extent to a caspase-3 inhibition.

  12. Effects of heavy metals on the neuromuscular transmission of the mouse diaphragm

    Energy Technology Data Exchange (ETDEWEB)

    Fu, W M; Shiau, S Y.L.

    1978-04-01

    Effects of heavy metals including Mn, Co, Ni, Cd, Zn, Cu, Sr, Ba, and UO/sub 2//sup +/ ions on the neuromuscular transmission of the mouse diaphragm were studied and compared. From the dose-inhibition curves, the concentrations (mM) required to inhibit 50% of the contraction (ID/sub 50/) for Cd, Mn, Co, Ni, Zn and Sr are 0.03, 0.8, 0.75, 0.82, 1.2 and >20 respectively. In addition to the potent neuromuscular blocking action, both Cd and Zn induce a contracture of the mouse diaphram. Among the cations tested, Cu is the most potent in inducing the contracture. Mn does not cause a contracture, while Co and Ni induce a contracture only after a prolonged incubation for 3 hours. The neuromuscular blocking action of most of the cations tested can be completely or partially reversed by either high Ca or cysteine except the irreversible action of Zn and Cu. These findings suggest that most divalent cations block the neuromuscular transmission by binding to the -SH group of the cell membrane and inhibiting Ca influx. On the other hand, both Ba and UO/sub 2/ at low concentration increase but at high concentration inhibit the twitch response. Sine Ba increases the twitch response of the mouse diaphragm stimulated directly in the presence of d-tubocurarine as well as that stimulated indirectly, Ba/sup + +/ acts mainly directly on the muscle. In contrast, UO/sub 2//sup +/ ions at low concentration increases the twitch response possibly by releasing acetylcholine from the nerve endings.

  13. Diaphragm motion quantification in megavoltage cone-beam CT projection images.

    Science.gov (United States)

    Chen, Mingqing; Siochi, R Alfredo

    2010-05-01

    To quantify diaphragm motion in megavoltage (MV) cone-beam computed tomography (CBCT) projections. User identified ipsilateral hemidiaphragm apex (IHDA) positions in two full exhale and inhale frames were used to create bounding rectangles in all other frames of a CBCT scan. The bounding rectangle was enlarged to create a region of interest (ROI). ROI pixels were associated with a cost function: The product of image gradients and a gradient direction matching function for an ideal hemidiaphragm determined from 40 training sets. A dynamic Hough transform (DHT) models a hemidiaphragm as a contour made of two parabola segments with a common vertex (the IHDA). The images within the ROIs are transformed into Hough space where a contour's Hough value is the sum of the cost function over all contour pixels. Dynamic programming finds the optimal trajectory of the common vertex in Hough space subject to motion constraints between frames, and an active contour model further refines the result. Interpolated ray tracing converts the positions to room coordinates. Root-mean-square (RMS) distances between these positions and those resulting from an expert's identification of the IHDA were determined for 21 Siemens MV CBCT scans. Computation time on a 2.66 GHz CPU was 30 s. The average craniocaudal RMS error was 1.38 +/- 0.67 mm. While much larger errors occurred in a few near-sagittal frames on one patient's scans, adjustments to algorithm constraints corrected them. The DHT based algorithm can compute IHDA trajectories immediately prior to radiation therapy on a daily basis using localization MVCBCT projection data. This has potential for calibrating external motion surrogates against diaphragm motion.

  14. Method of producing the arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels of nuclear reactors

    International Nuclear Information System (INIS)

    Kumpf, H.

    1976-01-01

    In producing arched surfaces of diaphragm rings for large containers, especially for prestressed-concrete pressure vessels for nuclear power plants, it is of advantage to manufacture these directly on the construction site. According to the invention the, at first level, diaphragm ring is put on the predetermined place, sectionally pressed against and shaped by a shaping tool - with a profiled supporting ring as a counter-acting tool - and afterwards welded together with the annular wall sections of the large container along the shaped parts. The manufacture of single and double configurations of diaphragm rings is described. It is of advantage if shaping and mounting position coincide. (UWI) [de

  15. DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

    Science.gov (United States)

    McDermott, Christopher J; Bradburn, Mike J; Maguire, Chin; Cooper, Cindy L; Baird, Wendy O; Baxter, Susan K; Cohen, Judith; Cantrill, Hannah; Dixon, Simon; Ackroyd, Roger; Baudouin, Simon; Bentley, Andrew; Berrisford, Richard; Bianchi, Stephen; Bourke, Stephen C; Darlison, Roy; Ealing, John; Elliott, Mark; Fitzgerald, Patrick; Galloway, Simon; Hamdalla, Hisham; Hanemann, C Oliver; Hughes, Philip; Imam, Ibrahim; Karat, Dayalan; Leek, Roger; Maynard, Nick; Orrell, Richard W; Sarela, Abeezar; Stradling, John; Talbot, Kevin; Taylor, Lyn; Turner, Martin; Simonds, Anita K; Williams, Tim; Wedzicha, Wisia; Young, Carolyn; Shaw, Pamela J

    2016-06-01

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health-care resource use; tolerability and adverse events. Acceptability and attitudes to

  16. Hydrophil diaphragms on the basis of perfluorated copolymers FEP and polyacryl nitrile: Manufacture by radiation- initiated grafting and their use for pervaporation

    International Nuclear Information System (INIS)

    Scholz, H.

    1986-01-01

    The radiation-initiated grafting copolymerisation of hydrophil monomers to FEP, a copolymer of tetrafluorethene and hexafluorpropene and to polyacryl nitrile (PAN) was examined in this dissertation. The grafted products were used as diaphragms for the separation of water-ethanol mixtures by pervaporation. Water was separated through the diaphragm from the mixture in the pervaporation experiments. It was shown how the mechanical properties of the basic polymer affect the interaction between basic polymer and grafted polymer and how the grafting conditions affect the diaphragm properties. By grafting acrylic acid on to the basic polymers FEP and PAN, very good results were achieved for the water-ethanol separation, if the diaphragms were used in the K form. The selectivity of PAN-g-acrylic acid-K for water reached values of α > 1000. (orig./RB) [de

  17. Effects of rocuronium and vecuronium on initial rundown of endplate potentials in the isolated phrenic nerve diaphragm preparation of rats

    OpenAIRE

    Li, Jun; Liu, Yong-Qin; Zhang, Han-Ting

    2013-01-01

    Rocuronium and vecuronium, two non-depolarizing neuromuscular blockers, have been widely used in surgery procedures. However, their electrophysiological properties need to be more widely explored. We examined the effects of rocuronium and vecuronium on initial rundown of endplate potential amplitudes in the non-uniform stretched muscle preparation of the rat isolated phrenic nerve diaphragm. More specifically, the endplate potentials were recorded with one microelectrode from a single endplat...

  18. Comparative morphology of the diaphragm of white tufted-ear marmoset and the white-fronted marmoset

    Directory of Open Access Journals (Sweden)

    Thais Borges Lessa

    2012-03-01

    Full Text Available The marmosets of the Callithrix genus have a great importance in the research field, not only for its occurrence in the ecosystems of South America and Central America, but also because of its small size and easy management. This study aimed to characterize the ultrastructure of the diaphragm of four adult animals of the C. jacchus species and four animals of the C. geoffroyi species that died from natural causes. Diaphragms were collected, dissected, and fixed in 10% formaldehyde and analyzed through scanning electron microscopy. It was observed the presence of an external membrane of connective tissue, with cylindrical muscle fibers arranged in rows perpendicular to the longitudinal axis and grouped into fascicles. In C. jacchus it was observed a discontinuous and linear fibers’ architecture, resulting in a score of 7 and 8 fascicles for male and female, respectively. In C. geoffroyi the fiber had a continuous shape, but also linear, yielding a total of 9 and 6 fascicles for male and female, respectively. The architecture of muscle fibers and the count of fascicles of the coastal face of the diaphragm suggest differences between the species C. geoffroyi and C. jacchus and between males and females, intra- and interspecies.

  19. Partial recovery of respiratory function and diaphragm reinnervation following unilateral vagus nerve to phrenic nerve anastomosis in rabbits.

    Directory of Open Access Journals (Sweden)

    Junxiang Wen

    Full Text Available Respiratory dysfunction is the leading cause of mortality following upper cervical spinal cord injury (SCI. Reinnervation of the paralyzed diaphragm via an anastomosis between phrenic nerve and a donor nerve is a potential strategy to mitigate ventilatory deficits. In this study, anastomosis of vagus nerve (VN to phrenic nerve (PN in rabbits was performed to assess the potential capacity of the VN to compensate for lost PN inputs. At first, we compared spontaneous discharge pattern, nerve thickness and number of motor fibers between these nerves. The PN exhibited a highly rhythmic discharge while the VN exhibited a variable frequency discharge pattern. The rabbit VN had fewer motor axons (105.3±12.1 vs. 268.1±15.4. Nerve conduction and respiratory function were measured 20 weeks after left PN transection with or without left VN-PN anastomosis. Compared to rabbits subjected to unilateral phrenicotomy without VN-PN anastomosis, diaphragm muscle action potential (AP amplitude was improved by 292%, distal latency by 695%, peak inspiratory flow (PIF by 22.6%, peak expiratory flow (PRF by 36.4%, and tidal volume by 21.8% in the anastomosis group. However, PIF recovery was only 28.0%, PEF 28.2%, and tidal volume 31.2% of Control. Our results suggested that VN-PN anastomosis is a promising therapeutic strategy for partial restoration of diaphragm reinnervation, but further modification and improvements are necessary to realize the full potential of this technique.

  20. Efficacy evaluation of laparoscopy assisted ultrasound guided radiofrequency ablation in the treatment of hepatocellular carcinoma beneath the diaphragm

    Directory of Open Access Journals (Sweden)

    Song WANG

    2017-06-01

    Full Text Available Objective To explore the feasibility, safety and efficacy of laparoscopy assisted ultrasound guided radiofrequency ablation (RFA in the treatment of hepatocellular carcinoma (HCC beneath the diaphragm. Methods Twenty- three consecutive patients with solitary HCC beneath the diaphragm were treated by laparoscopy assisted ultrasound guided RFA in the Chinese PLA General Hospital from January 2013 to March 2016. We observed the perioperative complications and followed- up long-term effect. Results All the 23 patients successfully underwent laparoscopy assisted ultrasound guided radiofrequency ablation. No serious complications such as massive hemorrhage, biliary fistula and severe pleural effusion, hemopneumothorax occurred in the patients during perioperative period. CT examination 2-3 days after the operation revealed that the tumor was completely covered by the ablation area. Besides, the survival condition was satisfactory during follow-up period of 9-38 months. Conclusion Laparoscopy-assisted ultrasound-guided radiofrequency ablation is effective and safe for HCC beneath the diaphragm. DOI: 10.11855/j.issn.0577-7402.2017.05.16

  1. Development of Optophone with No Diaphragm and Application to Sound Measurement in Jet Flow

    Directory of Open Access Journals (Sweden)

    Yoshito Sonoda

    2012-01-01

    Full Text Available The optophone with no diaphragm, which can detect sound waves without disturbing flow of air and sound field, is presented as a novel sound measurement technique and the present status of development is reviewed in this paper. The method is principally based on the Fourier optics and the sound signal is obtained by detecting ultrasmall diffraction light generated from phase modulation by sounds. The principle and theory, which have been originally developed as a plasma diagnostic technique to measure electron density fluctuations in the nuclear fusion research, are briefly introduced. Based on the theoretical analysis, property and merits as a wave-optical sound detection are presented, and the fundamental experiments and results obtained so far are reviewed. It is shown that sounds from about 100 Hz to 100 kHz can be simultaneously detected by a visible laser beam, and the method is very useful to sound measurement in aeroacoustics. Finally, present main problems of the optophone for practical uses in sound and/or noise measurements and the image of technology expected in the future are shortly shown.

  2. Po2 cycling protects diaphragm function during reoxygenation via ROS, Akt, ERK, and mitochondrial channels.

    Science.gov (United States)

    Zuo, Li; Pannell, Benjamin K; Re, Anthony T; Best, Thomas M; Wagner, Peter D

    2015-12-01

    Po2 cycling, often referred to as intermittent hypoxia, involves exposing tissues to brief cycles of low oxygen environments immediately followed by hyperoxic conditions. After experiencing long-term hypoxia, muscle can be damaged during the subsequent reintroduction of oxygen, which leads to muscle dysfunction via reperfusion injury. The protective effect and mechanism behind Po2 cycling in skeletal muscle during reoxygenation have yet to be fully elucidated. We hypothesize that Po2 cycling effectively increases muscle fatigue resistance through reactive oxygen species (ROS), protein kinase B (Akt), extracellular signal-regulated kinase (ERK), and certain mitochondrial channels during reoxygenation. Using a dihydrofluorescein fluorescent probe, we detected the production of ROS in mouse diaphragmatic skeletal muscle in real time under confocal microscopy. Muscles treated with Po2 cycling displayed significantly attenuated ROS levels (n = 5; P ROS, Akt, ERK, as well as chemical stimulators to close mitochondrial ATP-sensitive potassium channel (KATP) or open mitochondrial permeability transition pore (mPTP). All these blockers or stimulators abolished improved muscle function with Po2 cycling treatment. This current investigation has discovered a correlation between KATP and mPTP and the Po2 cycling pathway in diaphragmatic skeletal muscle. Thus we have identified a unique signaling pathway that may involve ROS, Akt, ERK, and mitochondrial channels responsible for Po2 cycling protection during reoxygenation conditions in the diaphragm. Copyright © 2015 the American Physiological Society.

  3. Laparoscopic repair of penetrating injury of the diaphragm: an experience from a district hospital

    Directory of Open Access Journals (Sweden)

    Ali Yahya

    2008-01-01

    Full Text Available In this study we review our experience in using laparoscopy as a diagnostic and therapeutic tool in dealing with penetrating diaphragmatic injuries due to stab wounds and look at the feasibility of using this procedure in other similar institutions.Thirty patients, all of whom were males 20-30 years of age, presented to the surgical emergency unit of our hospital with upper abdominal and lower chest wall stab wounds between 01-05-1998 and 30-11-2006. Diagnosis of the diaphragm injury was either obvious with omentum herniating through the chest wall, or occult with confirmation of the injury at laparoscopy.All patients underwent diagnostic laparoscopy, which resulted in identification and efficient treatment of eight patients with diaphragmatic injury, and thereby laparotomy was avoided. The procedure converted to open surgery in one patient because of a small left-sided colonic tear. Laparoscopy is an efficient tool for the diagnosis and management of diaphragmatic injuries. It should be used routinely instead of exploratory laparotomy in haemodynamically stable patients with penetrating lower chest injuries.

  4. Expansion of the neck reconstituted the shoulder-diaphragm in amniote evolution.

    Science.gov (United States)

    Hirasawa, Tatsuya; Fujimoto, Satoko; Kuratani, Shigeru

    2016-01-01

    The neck acquired flexibility through modifications of the head-trunk interface in vertebrate evolution. Although developmental programs for the neck musculoskeletal system have attracted the attention of evolutionary developmental biologists, how the heart, shoulder and surrounding tissues are modified during development has remained unclear. Here we show, through observation of the lateral plate mesoderm at cranial somite levels in chicken-quail chimeras, that the deep part of the lateral body wall is moved concomitant with the caudal transposition of the heart, resulting in the infolding of the expanded cervical lateral body wall into the thorax. Judging from the brachial plexus pattern, an equivalent infolding also appears to take place in mammalian and turtle embryos. In mammals, this infolding process is particularly important because it separates the diaphragm from the shoulder muscle mass. In turtles, the expansion of the cervical lateral body wall affects morphogenesis of the shoulder. Our findings highlight the cellular expansion in developing amniote necks that incidentally brought about the novel adaptive traits. © 2015 The Authors Development, Growth & Differentiation published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Developmental Biologists.

  5. Autoacceleration of electron beam and microwave radiation in the diaphragmed waveguide

    International Nuclear Information System (INIS)

    Kolomensky, A.A.; Meskhy, G.O.; Yablokov, B.N.

    1977-01-01

    The energy of a portion of beam electrons can be increased by means of the autoacceleration mechanism. In these experiments, an electron accelerator with parameters 0.5 to 1.0 MeV, 20 to 30 kA, 40 to 50 ns was used. A hollow beam was passed through a diaphragmed waveguide. At its output, the electron spectrum and microwave spectrum were measured simultaneously. About 10% of the electrons increase their energy as compared with the maximum input energy, whereby 3% increase their energy more than by a factor of two. The energy multiplication for the tail electrons turns out to be 3 to 4 times the initial value. About 10% of the beam input power is spent on the increase of electron energy. The pulse microwave power generated is in the range 2.7 to 2.9 GHz and its total measured power was approx. 0.4 GW, which corresponds to approx. 20% of the input beam power. Experiments show that effects of autoacceleration and microwave generation are interdependent and should be studied together

  6. Effect of Gymnodinium breve toxin in the rat phrenic nerve diaphragm preparation.

    Science.gov (United States)

    Gallagher, J. P.; Shinnick-Gallagher, P.

    1980-01-01

    1 The effects of a crude fraction of Gymnodinium breve toxin (GBTX) were studied on the rat phrenic nerve diaphragm preparation. 2 Indirectly stimulated muscle contractions were more sensitive to blockade by increasing concentrations of GBTX (0.25 microgram/ml to 10 micrograms/ml) than direct muscle contractions. 3 GBTX increased miniature endplate potential (m.e.p.p.) frequency and depolarized the resting membrane potential of the muscle fibres at the endplate and in non-synaptic regions of muscle fibre. 4 A concentration-dependent biphasic effect on m.e.p.p. amplitude was evident. At lower concentrations m.e.p.p. amplitudes were depressed whereas at high concentrations they were increased. 5 GBTX blocked endplate potentials (e.p.ps) in concentrations (0.5 microgram/ml to 2 micrograms/ml) that did not block m.e.p.ps. 6 Muscle fibre action potentials recorded from cells held at control membrane potential by hyperpolarizing current were not altered by toxin treatment. No repetitive e.p.ps, or muscle action potentials were observed. 7 These data suggest that GBTX may block indirectly stimulated muscle contractions and e.p.ps by depolarizing the nerve terminal in a manner similar to the observed depolarization of the muscle fibre. The depolarization of the nerve terminal may be sufficient to inhibit transmitter release. PMID:7190451

  7. Diaphragm pacing and noninvasive respiratory management of amyotrophic lateral sclerosis/motor neuron disease.

    Science.gov (United States)

    Mahajan, Kedar R; Bach, John Robert; Saporito, Lou; Perez, Nick

    2012-12-01

    Although it is known that continuous noninvasive ventilation (CNIV) can prolong life in amyotrophic lateral sclerosis/motor neuron disease (ALS/MND), in this study we explore similar claims for diaphragm pacing (DP). NIV and DP users' vital capacities (VCs) over time and duration of NIV and CNIV dependence were analyzed for 354 non-DP and 8 DP ALS/MND patients. Patients had a higher rate of monthly VC decline before NIV use (5.1 ± 7.6%) than during NIV use (2.5 ± 3.6%) (P NIV for 19.9 ± 27.6 months until tracheostomy/death, whereas 113 others used it for 10.9 ± 10.5 months until CNIV dependence for another 12.8 ± 16.2 months. After placement, 7 DP users were CNIV dependent in 8.0 ± 7.0 months, whereas 6 underwent tracheostomy/died in 18.2 ± 13.7 months. CNIV prolonged the survival of 113 of the 354 non-DP and 6 DP ALS/MND patients by 12.8 and 10.2 months, respectively. DP provided no benefit on VC or mechanical ventilation-free survival. Copyright © 2012 Wiley Periodicals, Inc.

  8. Restoration of diaphragmatic function after diaphragm reinnervation by inferior laryngeal nerve; experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    de Barros Angelique

    2006-01-01

    Full Text Available Abstract Objectives To assess the possibilities of reinnervation in a paralyzed hemidiaphragm via an anastomosis between phrenic nerve and inferior laryngeal nerve in rabbits. Reinnervation of a paralyzed diaphragm could be an alternative to treat patients with ventilatory insufficiency due to upper cervical spine injuries. Material and method Rabbits were divided into five groups of seven rabbits each. Groups I and II were respectively the healthy and the denervated control groups. The 3 other groups were all reinnervated using three different surgical procedures. In groups III and IV, phrenic nerve was respectively anastomosed with the abductor branch of the inferior laryngeal nerve and with the trunk of the inferior laryngeal nerve. In group V, the fifth and fourth cervical roots were respectively anastomosed with the abductor branch of the inferior laryngeal nerve and with the nerve of the sternothyroid muscle (originating from the hypoglossal nerve. Animals were evaluated 4 months later using electromyography, transdiaphragmatic pressure measurements, sonomicrometry and histological examination. Results A poor inspiratory activity was found in quiet breathing in the reinnervated groups, with an increasing pattern of activity during effort. In the reinnervated groups, transdiaphragmatic pressure measurements and sonomicrometry were higher in group III with no significant differencewith groups IV and V. Conclusion Inspiratory contractility of an hemidiaphragm could be restored with immediate anastomosis after phrenic nerve section between phrenic nerve and inferior laryngeal nerve.

  9. The Combination of Micro Diaphragm Pumps and Flow Sensors for Single Stroke Based Liquid Flow Control

    Directory of Open Access Journals (Sweden)

    Christoph Jenke

    2017-04-01

    Full Text Available With the combination of micropumps and flow sensors, highly accurate and secure closed-loop controlled micro dosing systems for liquids are possible. Implementing a single stroke based control mode with piezoelectrically driven micro diaphragm pumps can provide a solution for dosing of volumes down to nanoliters or variable average flow rates in the range of nL/min to μL/min. However, sensor technologies feature a yet undetermined accuracy for measuring highly pulsatile micropump flow. Two miniaturizable in-line sensor types providing electrical readout—differential pressure based flow sensors and thermal calorimetric flow sensors—are evaluated for their suitability of combining them with mircopumps. Single stroke based calibration of the sensors was carried out with a new method, comparing displacement volumes and sensor flow volumes. Limitations of accuracy and performance for single stroke based flow control are described. Results showed that besides particle robustness of sensors, controlling resistive and capacitive damping are key aspects for setting up reproducible and reliable liquid dosing systems. Depending on the required average flow or defined volume, dosing systems with an accuracy of better than 5% for the differential pressure based sensor and better than 6.5% for the thermal calorimeter were achieved.

  10. Improved vibration-based energy harvesting by annular mass configuration of piezoelectric circular diaphragms

    Science.gov (United States)

    Yang, Yangyiwei; Li, Yuanbo; Guo, Yaqian; Xu, Bai-Xiang; Yang, Tongqing

    2018-03-01

    Vibration-based energy harvesting using piezoelectric circular diaphragms (PCDs) with a structure featuring the central mass (C-mass) configuration has drawn much attention in recent decades. In this work, we propose a new configuration with the annular proof mass (A-mass) where an improved energy harvesting is promised. The numerical analysis was employed using the circuit-coupled piezoelectric simulation, and the experimental validation was implemented using PCDs with the even-width annular electrodes. Samples with the different mass configurations as well as structural parameters ϖ 1 and ϖ 2, which indicate the ratio between the inner boundary radius and piezoelectric ceramic radius as well as the ratio between outer boundary radius and the substrate radius, respectively, were prepared and tested. The impedance-matched output power of full-electrode PCDs was also collected, and some distinct improvement was measured on samples with the certain structural parameters. The power increases from 14.1 mW to 19.0 mW after changing the configuration from C-mass to A-mass with the same parameters (ϖ 1, ϖ 2) = (0.16, 0.9), showing the considerable improvement in energy harvesting by using A-mass configuration.

  11. The Combination of Micro Diaphragm Pumps and Flow Sensors for Single Stroke Based Liquid Flow Control.

    Science.gov (United States)

    Jenke, Christoph; Pallejà Rubio, Jaume; Kibler, Sebastian; Häfner, Johannes; Richter, Martin; Kutter, Christoph

    2017-04-03

    With the combination of micropumps and flow sensors, highly accurate and secure closed-loop controlled micro dosing systems for liquids are possible. Implementing a single stroke based control mode with piezoelectrically driven micro diaphragm pumps can provide a solution for dosing of volumes down to nanoliters or variable average flow rates in the range of nL/min to μL/min. However, sensor technologies feature a yet undetermined accuracy for measuring highly pulsatile micropump flow. Two miniaturizable in-line sensor types providing electrical readout-differential pressure based flow sensors and thermal calorimetric flow sensors-are evaluated for their suitability of combining them with mircopumps. Single stroke based calibration of the sensors was carried out with a new method, comparing displacement volumes and sensor flow volumes. Limitations of accuracy and performance for single stroke based flow control are described. Results showed that besides particle robustness of sensors, controlling resistive and capacitive damping are key aspects for setting up reproducible and reliable liquid dosing systems. Depending on the required average flow or defined volume, dosing systems with an accuracy of better than 5% for the differential pressure based sensor and better than 6.5% for the thermal calorimeter were achieved.

  12. Emphysema quantification from CT scans using novel application of diaphragm curvature estimation: comparison with standard quantification methods and pulmonary function data

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Yankelevitz, David F.; Henschke, Claudia I.; Barr, R. Graham

    2009-02-01

    Emphysema is a disease of the lungs that destroys the alveolar air sacs and induces long-term respiratory dysfunction. CT scans allow for the imaging of the anatomical basis of emphysema and quantification of the underlying disease state. Several measures have been introduced for the quantification emphysema directly from CT data; most,however, are based on the analysis of density information provided by the CT scans, which vary by scanner and can be hard to standardize across sites and time. Given that one of the anatomical variations associated with the progression of emphysema is the flatting of the diaphragm due to the loss of elasticity in the lung parenchyma, curvature analysis of the diaphragm would provide information about emphysema from CT. Therefore, we propose a new, non-density based measure of the curvature of the diaphragm that would allow for further quantification methods in a robust manner. To evaluate the new method, 24 whole-lung scans were analyzed using the ratios of the lung height and diaphragm width to diaphragm height as curvature estimates as well as using the emphysema index as comparison. Pearson correlation coefficients showed a strong trend of several of the proposed diaphragm curvature measures to have higher correlations, of up to r=0.57, with DLCO% and VA than did the emphysema index. Furthermore, we found emphysema index to have only a 0.27 correlation to the proposed measures, indicating that the proposed measures evaluate different aspects of the disease.

  13. Mechanical characterization of the mouse diaphragm with optical coherence elastography reveals fibrosis-related change of direction-dependent muscle tissue stiffness

    Science.gov (United States)

    Wang, Shang; Loehr, James A.; Larina, Irina V.; Rodney, George G.; Larin, Kirill V.

    2016-03-01

    The diaphragm, composed of skeletal muscle, plays an important role in respiration through its dynamic contraction. Genetic and molecular studies of the biomechanics of mouse diaphragm can provide great insights into an improved understanding and potential treatment of the disorders that lead to diaphragm dysfunction (i.e. muscular dystrophy). However, due to the small tissue size, mechanical assessment of mouse diaphragm tissue under its proper physiological conditions has been challenging. Here, we present the application of noncontact optical coherence elastography (OCE) for quantitative elastic characterization of ex vivo mouse diaphragm. Phase-sensitive optical coherence tomography was combined with a focused air-puff system to capture and measure the elastic wave propagation from tissue surface. Experiments were performed on wildtype and dystrophic mouse diaphragm tissues containing different levels of fibrosis. The OCE measurements of elastic wave propagation were conducted along both the longitudinal and transverse axis of the muscle fibers. Cross-correlation of the temporal displacement profiles from different spatial locations was utilized to obtain the propagation time delay, which was used to calculate the wave group velocity and to further quantify the tissue Young's modulus. Prior to and after OCE assessment, peak tetanic force was measured to monitor viability of the tissue during the elasticity measurements. Our experimental results indicate a positive correlation between fibrosis level and tissue stiffness, suggesting this elastic-wave-based OCE method could be a useful tool to monitor mechanical properties of skeletal muscle under physiological and pathological conditions.

  14. Correlation of Respiratory Activity of Contralateral Diaphragm Muscles for Evaluation of Recovery Following Hemiparesis

    Science.gov (United States)

    Dow, Douglas E.; Zhan, Wen-Zhi; Sieck, Gary C.; Mantilla, Carlos B.

    2014-01-01

    Respiration is impaired by disruption of the central drive for inspiration to the diaphragm muscle (DIAm). Some function may recover involving nerve regeneration, reinnervation or neuroplasticity. A research animal model involves inducing hemiparesis of the DIAm and monitoring any recovery under different conditions. Methods to accurately track the level of functional recovery are needed. In this study, an algorithm was developed and tested to quantify the relative amount of electromyogram (EMG) activity that temporally correlated for an experimental (EXP) hemi-DIAm with its intact contralateral hemi-DIAm. An average rectified value (ARV) trace was calculated. A template was formed of the ARV trace of the intact hemi-DIAm, with higher positive values corresponding with periods of inspirations and lower negative values corresponding with quiet periods. This template was multiplied by the EXP ARV trace to reward (more positive) periods of correlating activity, and punish (more negative) periods of high activity on the EXP side that corresponded with quiet periods on the intact side. The average integrated value was the index of correlating contralateral activity (ICCA). A negative ICCA value indicated no net correlation of activity, and a positive value indicated a net correlation of activity. The algorithm was tested on rats having the conditions of control or hemi-paresis induced by denervatation (DNV), tetrodotoxin administration (TTX) or cervical spinal hemi-section (SH). Control had high positive ICCA values, and DNV had negative values. TTX maintained negative ICCA values at 3, 7 and 14 days, indicating a lack of functional recovery. SH maintained negative values at 3 and 7 days, but a subset had positive values at 14 days indicating some functional recovery. PMID:19965125

  15. Black diaphragm intraocular lens implantation and penetrating keratoplasty in aphakic eyes with traumatic aniridia

    Directory of Open Access Journals (Sweden)

    Xiao-Guang Dong

    2013-04-01

    Full Text Available AIM: To evaluate the long-term outcome of implantation of black diaphragm intraocular (BDI lens combined with penetrating keratoplasty (PKP for managing aphakic eyes with traumatic aniridia and corneal damage. METHODS: Six aphakic eyes of six patients with traumatic aniridia and corneal damage had BDI lens implantation at Qingdao Eye Hospital, Shandong Eye Institute from June 2008 to November 2011. Medical records of the patients were reviewed. Three patients received PKP and after 12-18months were implanted with BDI lens. The other three patients completed PKP and BDI lens implantation at the same time. The corrected visual acuity, intraocular pressure and number of corneal endothelial cells were monitored. RESULTS: The patients were followed up for an average of 24.3±12.1months (range 14-48 months. All BDI lenses were located well. The best corrected visual acuity got improved in 5 patients (0.1-1.0 and decreased in 1 patient from 0.4 to 0.2. Three patients had normal intraocular pressure (IOP after implantation. Two patients required antiglaucoma medications to control IOP within the normal range and 1 patient implanted Ahmed glaucoma valve to control IOP. The corneal grafts kept transparent in all eyes and the corneal endothelial counting >1 000/mm2, although two patients experienced acute graft rejection and loss more than 30% corneal endothelial cells. CONCLUSION: Implantation of BDI lens combined with PKP is an effective option for managing aphakic eyes with traumatic aniridia and corneal damage. Although the results in our study are encouraging, additional studies of the long-term safety and efficacy are required. A larger study population and longer follow-up may be beneficial.

  16. Resistance to rocuronium of rat diaphragm as compared with limb muscles.

    Science.gov (United States)

    Huang, Lina; Yang, Meirong; Chen, Lianhua; Li, Shitong

    2014-12-01

    Skeletal muscles are composed of different muscle fiber types. We investigated the different potency to rocuronium among diaphragm (DIA), extensor digitorum longus (EDL), and soleus (SOL) in vitro as well as to investigate the differences of acetylcholine receptors (AChRs) among these three typical kinds of muscles. The isolated left hemidiaphragm nerve-muscle preparations, the EDL sciatic nerve-muscle preparations, and the SOL sciatic nerve-muscle preparations were established to evaluate the potency to rocuronium. Concentration-response curves were constructed and the values of IC50 were obtained. The density of AChRs at the end plate and the number of AChRs per unit fiber cross fiber area (CSA), AChR affinity for muscle relaxants were evaluated. The concentration-twitch tension curves of rocuronium were significantly different. The curves demonstrated a shift to the right of the DIA compared with the EDL and SOL (P  0.05). IC50 was significantly largest in DIA, second largest in SOL, and smallest in EDL (P rocuronium of DIA compared with EDL and SOL was verified. The DIA was characterized by the largest number of AChRs per unit fiber CSA and the lowest affinity of the AChRs. Although compared with SOL, EDL was proved to have larger number of AChRs per unit fiber CSA and the lower affinity of the AChRs. These findings may be the mechanisms of different potency to rocuronium in DIA, EDL, and SOL. The results of the study could help to explain the relationship between different composition of muscle fibers and the potency to muscle relaxants. Extra caution should be taken in clinical practice when monitoring muscle relaxation in anesthetic management using different muscles. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Three-dimensional quadratic modeling and quantitative evaluation of the diaphragm on a volumetric CT scan in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yongjun [School of Electrical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34138 (Korea, Republic of); Bae, Jangpyo [Interdisciplinary Program, Bioengineering Major, Graduate School, Seoul National University, Seoul 08826 (Korea, Republic of); Kim, Namkug, E-mail: namkugkim@gmail.com [Department of Convergence Medicine, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505 (Korea, Republic of); Park, Joo-Young; Lee, Sang Min; Seo, Joon Beom [Department of Radiology, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505 (Korea, Republic of)

    2016-07-15

    Purpose: In patients with chronic obstructive pulmonary disease (COPD), diaphragm function may deteriorate due to reduced muscle fiber length. Quantitative analysis of the morphology of the diaphragm is therefore important. In the authors current study, they propose a diaphragm segmentation method for COPD patients that uses volumetric chest computed tomography (CT) data, and they provide a quantitative analysis of the diaphragmatic dimensions. Methods: Volumetric CT data were obtained from 30 COPD patients and 10 normal control patients using a 16-row multidetector CT scanner (Siemens Sensation 16) with 0.75-mm collimation. Diaphragm segmentation using 3D ray projections on the lower surface of the lungs was performed to identify the draft diaphragmatic lung surface, which was modeled using quadratic 3D surface fitting and robust regression in order to minimize the effects of segmentation error and parameterize diaphragm morphology. This result was visually evaluated by an expert thoracic radiologist. To take into consideration the shape features of the diaphragm, several quantification parameters—including the shape index on the apex (SIA) (which was computed using gradient set to 0), principal curvatures on the apex on the fitted diaphragm surface (CA), the height between the apex and the base plane (H), the diaphragm lengths along the x-, y-, and z-axes (XL, YL, ZL), quadratic-fitted diaphragm lengths on the z-axis (FZL), average curvature (C), and surface area (SA)—were measured using in-house software and compared with the pulmonary function test (PFT) results. Results: The overall accuracy of the combined segmentation method was 97.22% ± 4.44% while the visual accuracy of the models for the segmented diaphragms was 95.28% ± 2.52% (mean ± SD). The quantitative parameters, including SIA, CA, H, XL, YL, ZL, FZL, C, and SA were 0.85 ± 0.05 (mm{sup −1}), 0.01 ± 0.00 (mm{sup −1}), 17.93 ± 10.78 (mm), 129.80 ± 11.66 (mm), 163.19 ± 13.45 (mm), 71

  18. Clinical study of ultrasound-guided percutaneous radiofrequency ablation for primary hepatic carcinoma adjacent to the diaphragm

    Directory of Open Access Journals (Sweden)

    LI Meng

    2015-04-01

    Full Text Available ObjectiveTo investigate the safety and efficacy of ultrasound (US-guided percutaneous radiofrequency ablation (RFA for primary hepatic carcinoma adjacent to the diaphragm. MethodsThis study included 277 patients with 362 lesions of primary hepatic carcinoma managed with US-guided percutaneous RFA in 302 Hospital of PLA from January 2011 to October 2014. Sixty-six patients with 71 hepatocellular carcinomas (HCCs located less than 5 mm from the diaphragm were in study group, and 95 patients with 114 HCCs located more than 10 mm from the hepatic surface were in control group. The patients′ symptoms and complications were observed after the therapy. The complete ablation rate, local tumor progression rate, and complication rate were compared between the two groups. Comparison of continuous data between the two groups was made by independent-samples t test, while comparison of categorical data was made by chi-square test. ResultsAt one month after operation, 65 (91.5% of 71 tumors in the study group and 107 (93.9% of 114 tumors in the control group achieved complete ablation, according to contrast-enhanced CT and MRI, and there was no significant difference between the two groups (χ2=0.36, P=0.55. The postoperative follow-up showed that the local tumor progression rates in the study group and control group were 16.9% and 13.2%, respectively, without significant difference between the two groups (χ2=0.49, P=0.48. In the study group, 22 patients developed adverse reactions, versus 37 patients in the control group (χ2=2.60, P=0.11. ConclusionUS-guided percutaneous RFA is a safe and effective means for the treatment of primary hepatic carcinoma adjacent to the diaphragm.

  19. Elevated Hemi-diaphragms as a Cause of ST-segment Elevation: A case report and review of literature.

    Science.gov (United States)

    Singh, Manmohan; Sood, Aditya; Rehman, Mobeen Ur; Othman, Mahmoud; Afonso, Luis

    While ST-segment elevation (STE) on ECG is widely recognized as representing myocardial infarction or injury such as coronary occlusion or pericarditis, STE may occasionally ensue from non-cardiac etiologies. Indeed, gastrointestinal disorders causing STE are not well documented in the literature. We present a case wherein extreme abdominal distension and hemi-diaphragm elevation resulted in extrinsic cardiac and epicardial coronary compression manifesting as STE. Subsequent relief of the abdominal distension resulted in resolution of STE representing a noncoronary cause of STE. A brief literature review, illustrating the importance of considering abdominal etiologies as a cause of STE is provided. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Numerical Analysis of Diaphragm Wall Model Executed in Poznań Clay Formation Applying Selected Fem Codes

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    Superczyńska M.

    2016-09-01

    Full Text Available The paper presents results of numerical calculations of a diaphragm wall model executed in Poznań clay formation. Two selected FEM codes were applied, Plaxis and Abaqus. Geological description of Poznań clay formation in Poland as well as geotechnical conditions on construction site in Warsaw city area were presented. The constitutive models of clay implemented both in Plaxis and Abaqus were discussed. The parameters of the Poznań clay constitutive models were assumed based on authors’ experimental tests. The results of numerical analysis were compared taking into account the measured values of horizontal displacements.

  1. Diaphragm Repair with a Novel Cross-Linked Collagen Biomaterial in a Growing Rabbit Model.

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    Steffi Mayer

    Full Text Available Neonates with congenital diaphragmatic hernia and large defects often require patch closure. Acellular collagen matrices (ACM have been suggested as an alternative to synthetic durable patches as they are remodeled by the host or could also be used for tissue engineering purposes.2.0x1.0 cm diaphragmatic defects were created in 6-weeks old New-Zealand white rabbits. We compared reconstruction with a purpose-designed cross-linked ACM (Matricel to 4-layer non-cross-linked small intestinal submucosa (SIS and a 1-layer synthetic Dual Mesh (Gore-Tex. Unoperated animals or animals undergoing primary closure (4/0 polyglecaprone served as age-matched controls. 60 (n = 25 resp. 90 (n = 17 days later, animals underwent chest x-ray and obduction for gross examination of explants, scoring of adhesion and inflammatory response. Also, uniaxial tensiometry was done, comparing explants to contralateral native diaphragmatic tissue.Overall weight nearly doubled from 1,554±242 g at surgery to 2,837±265 g at obduction (+84%. X-rays did show rare elevation of the left diaphragm (SIS = 1, Gore-Tex = 1, unoperated control = 1, but no herniation of abdominal organs. 56% of SIS and 10% of Matricel patches degraded with visceral bulging in four (SIS = 3, Matricel = 1. Adhesion scores were limited: 0.5 (Matricel to 1 (SIS, Gore-Tex to the left lung (p = 0.008 and 2.5 (Gore-Tex, 3 (SIS and 4 (Matricel to the liver (p<0.0001. Tensiometry revealed a reduced bursting strength but normal compliance for SIS. Compliance was reduced in Matricel and Gore-Tex (p<0.01. Inflammatory response was characterized by a more polymorphonuclear cell (SIS resp. macrophage (Matricel type of infiltrate (p<0.05. Fibrosis was similar for all groups, except there was less mature collagen deposited to Gore-Tex implants (p<0.05.Matricel induced a macrophage-dominated inflammatory response, more adhesions, had appropriate strength but a lesser compliance compared to native tissue. The herein

  2. Liquid Metal Droplet and Micro Corrugated Diaphragm RF-MEMS for reconfigurable RF filters

    Science.gov (United States)

    Irshad, Wasim

    detail and have proved pivotal to this work. The second part of the dissertation focuses on the Liquid Metal Droplet RF-MEMS. A novel tunable RF MEMS resonator that is based upon electrostatic control over the morphology of a liquid metal droplet (LMD) is conceived. We demonstrate an LMD evanescent-mode cavity resonator that simultaneously achieves wide analog tuning from 12 to 18 GHz with a measured quality factor of 1400-1840. A droplet of 250-mum diameter is utilized and the applied bias is limited to 100 V. This device operates on a principle called Electro-Wetting On Dielectric (EWOD). The liquid metal employed is a non-toxic eutectic alloy of Gallium, Indium and Tin known as Galinstan. This device also exploits interfacial surface energy and viscous body forces that dominate at nanoliter scale. We then apply our Liquid Metal Droplet (LMD) RF-MEMS architecture to demonstrate a continuously tunable electrostatic Ku-Band Filter. A 2-pole bandpass filter with measured insertion loss of less than 0.4dB and 3dB FBW of 3.4% is achieved using a Galinstan droplet of 250mum diameter and bias limited to 100V. We demonstrate that the LMD is insensitive to gravity by performing inversion and tilt experiments. In addition, we study its thermal tolerance by subjecting the LMD up to 150° C. The third part of the dissertation is dedicated to the Micro-Corrugated Diaphragm (MCD) RF-MEMS. We present an evanescent-mode cavity bandpass filter with state-of-the-art RF performance metrics like 4:1 tuning ratio from 5 to 20 GHz with less than 2dB insertion loss and 2-6% 3dB bandwidth. Micro-Corrugated Diaphragm (MCD) is a novel electrostatic MEMS design specifically engineered to provide large-scale analog deflections necessary for such continuous and wide tunable filtering with very high quality factor. We demonstrate a 1.25mm radius and 2mum thick Gold MCD which provides 30mum total deflection with nearly 60% analog range. We also present a detailed and systematic MCD design

  3. Effects of Growth Hormone Gene Polymorphism on Lipogenic Gene Expression Levels in Diaphragm Tissues of Japanese Black Heifers

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    Astrid Ardiyanti

    2012-08-01

    Full Text Available Two SNPs, i.e. L127V and T172M, of bovine growth hormone (GH causing the presence of GH gene haplotypes A, B, and C was previously shown to alter intramuscular fatty acid (FA composition in Japanese Black (JB heifers. To determine the SNP effect on somatotropic hormone concentration and lipogenesis, we measured plasma GH, insulin, and insulin-like growth factor-1 (IGF-1 concentrations. We also measured mRNA levels of fatty acid synthase (FASN, stearoyl-coA desaturase (SCD, and sterol regulatory element binding proteins-1 (SREBP-1 and FA composition in diaphragm tissues. Heifers with genotype CC had the lowest plasma insulin concentration and FASN and SCD mRNA levels among genotypes. FASN mRNA levels in haplotype A tended to positively correlate with saturated FA (SFA content and negatively correlated with C18:2 and unsaturated FA (USFA contents. SCD mRNA levels in haplotype A positively correlated with monounsaturated FA (MUFA contents and negatively correlated with C18:0 content. They also tended to positively correlate with C16:1, C18:1, and USFA contents and USFA/SFA ratio and negatively correlate with SFA content. Taken together, GH gene polymorphism affects the lipogenic genes expression levels and their relationships with fatty acid compositions in diaphragm tissues of JB heifers at 31 months of age.

  4. Air bio-battery with a gas/liquid porous diaphragm cell for medical and health care devices.

    Science.gov (United States)

    Arakawa, Takahiro; Xie, Rui; Seshima, Fumiya; Toma, Koji; Mitsubayashi, Kohji

    2018-04-30

    Powering future generations of medical and health care devices mandates the transcutaneous transfer of energy or harvesting energy from the human body fluid. Glucose-driven bio fuel cells (bio-batteries) demonstrate promise as they produce electrical energy from glucose, which is a substrate presents in physiological fluids. Enzymatic biofuel cells can convert chemical energy into electrical energy using enzymes as catalysts. In this study, an air bio-battery was developed for healthcare and medical applications, consisting of a glucose-driven enzymatic biofuel cell using a direct gas-permeable membrane or a gas/liquid porous diaphragm. The power generation characteristics included a maximum current density of 285μA/cm 2 and maximum power density of 70.7μW/cm 2 in the presence of 5mmol/L of glucose in solution. In addition, high-performance, long-term-stabilized power generation was achieved using the gas/liquid porous diaphragm for the reactions between oxygen and enzyme. This system can be powered using 5mmol/L of glucose, the value of which is similar to that of the blood sugar range in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Generalized free-space diffuse photon transport model based on the influence analysis of a camera lens diaphragm.

    Science.gov (United States)

    Chen, Xueli; Gao, Xinbo; Qu, Xiaochao; Chen, Duofang; Ma, Xiaopeng; Liang, Jimin; Tian, Jie

    2010-10-10

    The camera lens diaphragm is an important component in a noncontact optical imaging system and has a crucial influence on the images registered on the CCD camera. However, this influence has not been taken into account in the existing free-space photon transport models. To model the photon transport process more accurately, a generalized free-space photon transport model is proposed. It combines Lambertian source theory with analysis of the influence of the camera lens diaphragm to simulate photon transport process in free space. In addition, the radiance theorem is also adopted to establish the energy relationship between the virtual detector and the CCD camera. The accuracy and feasibility of the proposed model is validated with a Monte-Carlo-based free-space photon transport model and physical phantom experiment. A comparison study with our previous hybrid radiosity-radiance theorem based model demonstrates the improvement performance and potential of the proposed model for simulating photon transport process in free space.

  6. Scattering study at free air ionization chamber diaphragm; Estudo do espalhamento no diafragma da camara de ionizacao de ar livre

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Alexandre Lo Bianco dos

    2011-07-01

    The maim of this work consisted in the assessment of the correction factor for air kerma, due to scattered radiation in the diaphragm of the free-air ionization chamber model 481. LNMRl measurements were made to acquire x-ray spectra corresponding to the Qualities RQR-M, described in IEC 61627 standards (2005). These spectra were used as input data in the MC simulations. The operational range of energy spectra provide up to 35 keV. This energy range is typically used in diagnostic radiology, although there is not primary standard for air kerma. The determination of this factor is a fundamental process in the primary standardization of the air kerma. These factors were obtained by computer simulation using the Penelope code. The results are k{sub RQR-M1}=0,9946, k{sub RQR} {sub -M2}=0,9932, k{sub RQR-M3}=0,9978 and k{sub RQR-M4}=0,9885; with uncertainties of 0,007 and coverage factor equal to 2. lt can be concluded that, with respect to the diaphragm, the chamber can be used in the primary standard of air kerma. (author)

  7. Energy loss in electrochemical diaphragm process of chlorine and alkali industry - A collateral effect of the undesirable generation of chlorate

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Phabyanno Rodrigues; Mirapalheta, Almir; e Silva Zanta, Carmem Lucia de Paiva; Tonholo, Josealdo [Instituto de Quimica e Biotecnologia, Universidade Federal de Alagoas, 57072970 Maceio, AL (Brazil); Henrique dos Santos Andrade, Marcio [Instituto de Quimica e Biotecnologia, Universidade Federal de Alagoas, 57072970 Maceio, AL (Brazil); Braskem S/A, Maceio, AL (Brazil); Vilar, Eudesio Oliveira [Departamento de Engenharia Quimica, Universidade Federal de Campina, Grande, Campina Grande, PB (Brazil)

    2010-05-15

    Contamination of NaOH with chlorate constitutes a major problem for the chlorine-alkali industry, particularly when electrolytic cells based on the diaphragm process are employed. In this paper, pilot and laboratory cell experiments revealed that chlorate contamination in diaphragm cells also inhibits hydrogen evolution and gives rise to a significant increase in electrical energy consumption. Electrolysis carried out under conditions that simulated the industrial process (current density 240 mA cm{sup -2}; temperature 90 C; brine flux 23 L cm{sup -2} h{sup -1}) revealed that chlorate formation depends on brine flux and NaOH production. The inhibitory effect of chlorate on the main cathodic reaction was demonstrated in bench cell experiments, with cathodic displacement of the hydrogen evolution reaction by more than 100 mV in the presence of 0.4% chlorate compared with ideal conditions in which chlorate formation was absent. This hydrogen generation overpotential can charge the total electric energy balance in more than 5% of the total value, consisting of a critical loss for this process. (author)

  8. Role of the medial medullary reticular formation in relaying vestibular signals to the diaphragm and abdominal muscles

    Science.gov (United States)

    Mori, R. L.; Bergsman, A. E.; Holmes, M. J.; Yates, B. J.

    2001-01-01

    Changes in posture can affect the resting length of respiratory muscles, requiring alterations in the activity of these muscles if ventilation is to be unaffected. Recent studies have shown that the vestibular system contributes to altering respiratory muscle activity during movement and changes in posture. Furthermore, anatomical studies have demonstrated that many bulbospinal neurons in the medial medullary reticular formation (MRF) provide inputs to phrenic and abdominal motoneurons; because this region of the reticular formation receives substantial vestibular and other movement-related input, it seems likely that medial medullary reticulospinal neurons could adjust the activity of respiratory motoneurons during postural alterations. The objective of the present study was to determine whether functional lesions of the MRF affect inspiratory and expiratory muscle responses to activation of the vestibular system. Lidocaine or muscimol injections into the MRF produced a large increase in diaphragm and abdominal muscle responses to vestibular stimulation. These vestibulo-respiratory responses were eliminated following subsequent chemical blockade of descending pathways in the lateral medulla. However, inactivation of pathways coursing through the lateral medulla eliminated excitatory, but not inhibitory, components of vestibulo-respiratory responses. The simplest explanation for these data is that MRF neurons that receive input from the vestibular nuclei make inhibitory connections with diaphragm and abdominal motoneurons, whereas a pathway that courses laterally in the caudal medulla provides excitatory vestibular inputs to these motoneurons.

  9. Change in concentration of inorganic phosphate and phosphocreatine in the rat diaphragm under the influence of whole-body gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Mansour, M A; Gaber, M; Abdel-Fatah, K I

    1987-01-01

    The influence of irradiation on the concentration of creatine phosphate and inorganic phosphate in the diaphragm muscle were studied in rats exposed to 400 rad and 800 rad whole-body gamma radiation. The results showed that on the first day of post-exposure with 400 rad, the creatine phosphate concentration significantly increased, while the level significantly decreased on the third up to the fourteenth days of post exposure. In animals exposed to 800 rad, the diaphragm phosphocreatine showed a significant decrease on the first up to the ninth day post-irradiation as compared with the control group.

  10. Change in concentration of inorganic phosphate and phosphocreatine in the rat diaphragm under the influence of whole-body gamma irradiation

    International Nuclear Information System (INIS)

    Mansour, M.A.; Gaber, M.; Abdel-Fatah, K.I.

    1987-01-01

    The influence of irradiation on the concentration of creatine phosphate and inorganic phosphate in the diaphragm muscle were studied in rats exposed to 400 rad and 800 rad whole-body gamma radiation. The results showed that on the first day of post-exposure with 400 rad, the creatine phosphate concentration significantly increased, while the level significantly decreased on the third up to the fourteenth days of post exposure. In animals exposed to 800 rad, the diaphragm phosphocreatine showed a significant decrease on the first up to the ninth day post-irradiation as compared with the control group

  11. Simple and effective solution for diaphragm pacing by that uses the transvenous femoral approach in a patient treated with cardiac resynchronization-defibrillator therapy: The wrapping method

    Directory of Open Access Journals (Sweden)

    Ahmet Taha Alper, Prof.

    2017-08-01

    Full Text Available The use of cardiac resynchronization therapy (CRT has become widespread in patients with heart failure who meet the criteria for implantation. Coronary sinus lead positioning is important to provide the intended biventricular stimulation. Diaphragm pacing is a lead-related complication which occurs secondary to phrenic nerve stimulation. We present the case of a 58-year-old male patient who had diaphragm pacing after CRT with defibrillator implantation. The complication was resolved by using the transvenous femoral approach with the wrapping method.

  12. Electromyographic Study of Differential Sensitivity to Succinylcholine of the Diaphragm, Laryngeal and Somatic Muscles: A Swine Model

    Directory of Open Access Journals (Sweden)

    I-Cheng Lu

    2010-12-01

    Full Text Available Neuromuscular blocking agents (NMBAs might diminish the electromyography signal of the vocalis muscles during intraoperative neuromonitoring of the recurrent laryngeal nerve. The aim of this study was to compare differential sensitivity of different muscles to succinylcholine in a swine model, and to realize the influence of NMBAs on neuromonitoring. Six male Duroc-Landrace piglets were anesthetized with thiamylal and underwent tracheal intubation without the use of an NMBA. The left recurrent laryngeal nerve, the spinal accessory nerve, the right phrenic nerve and the brachial plexus were stimulated. Evoked potentials (electromyography signal of four muscle groups were elicited from needle electrodes before and after intravenous succinylcholine bolus (1.0 mg/kg. Recorded muscles included the vocalis muscles, trapezius muscle, diaphragm and triceps brachii muscles. The onset time and 80% recovery of control response were recorded and analyzed. The testing was repeated after 30 minutes. The onset time of neuromuscular blocking for the vocalis muscles, trapezius muscle, diaphragm and triceps brachii muscle was 36.3 ± 6.3 seconds, 38.8 ± 14.9 seconds, 52.5 ± 9.7 seconds and 45.0 ± 8.2 seconds during the first test; and 49.3 ± 10.8 seconds, 40.0 ± 12.2 seconds, 47.5 ± 11.9 seconds and 41.3 ± 10.1 seconds during the second test. The 80% recovery of the control response for each muscle was 18.3 ± 2.7 minutes, 16.5±6.9 minutes, 8.1±2.5 minutes and 14.8±2.9 minutes during the first test; and 21.5±3.8 minutes, 12.5 ± 4.3 minutes, 10.5 ± 3.1 minutes and 16.4 ± 4.2 minutes during the second test. The sensitivity of the muscles to succinylcholine, ranked in order, was: the vocalis muscles, the triceps brachii muscle, the trapezius muscle and the diaphragm. We demonstrated a useful and reliable animal model to investigate the effects of NMBAs on intraoperative neuromonitoring. Extrapolation of these data to humans should be done with caution.

  13. One stage resection of spontaneous rupture of hepatocellular carcinoma in the triangular ligament with diaphragm invasion: case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Park Kwang-Kuk

    2012-09-01

    Full Text Available Abstract A spontaneous rupture of hepatocellular carcinoma (HCC can lead to extensive hemorrhage and is a rare but life-threatening event. A 58-year-old male patient with no history of trauma presented at our institution with severe epigastric pain and abdominal distension for 6 h. His blood pressure was a 60/40 mmHg, and pulse rate was 132/min. Abdominal contrast enhanced computed tomography (CT imaging revealed a ruptured mass under the left diaphragm and fluid collection in the upper abdomen, flanks and pelvic cavity. Exploratory laparotomy confirmed the presence of an active bleeding tumor in the triangular ligament invading into the diaphragm. The tumor was resected with an appropriate diaphragm margin. The resected tumor was 5 cm in diameter and pathologically identified as hepatocellular carcinoma with a negative surgical margin. This case report shows that ruptured hepatocellular carcinoma should be considered in the differential diagnosis of non-traumatic hemoperitoneum. And it is necessary to set a surgical plan for unpredictable HCC rupture with direct diaphragm invasion.

  14. Non-stationarity and power spectral shifts in EMG activity reflect motor unit recruitment in rat diaphragm muscle.

    Science.gov (United States)

    Seven, Yasin B; Mantilla, Carlos B; Zhan, Wen-Zhi; Sieck, Gary C

    2013-01-15

    We hypothesized that a shift in diaphragm muscle (DIAm) EMG power spectral density (PSD) to higher frequencies reflects recruitment of more fatigable fast-twitch motor units and motor unit recruitment is reflected by EMG non-stationarity. DIAm EMG was recorded in anesthetized rats during eupnea, hypoxia-hypercapnia (10% O(2)-5% CO(2)), airway occlusion, and sneezing (maximal DIAm force). Although power in all frequency bands increased progressively across motor behaviors, PSD centroid frequency increased only during sneezing (pmotor units were recruited during different motor behaviors. Motor units augmented their discharge frequencies progressively beyond the non-stationary period; yet, EMG signal became stationary. In conclusion, non-stationarity of DIAm EMG reflects the period of motor unit recruitment, while a shift in the PSD towards higher frequencies reflects recruitment of more fatigable fast-twitch motor units. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Fabrication of polymer micro-lens array with pneumatically diaphragm-driven drop-on-demand inkjet technology.

    Science.gov (United States)

    Xie, Dan; Zhang, Honghai; Shu, Xiayun; Xiao, Junfeng

    2012-07-02

    The paper reports an effective method to fabricate micro-lens arrays with the ultraviolet-curable polymer, using an original pneumatically diaphragm-driven drop-on-demand inkjet system. An array of plano convex micro-lenses can be formed on the glass substrate due to surface tension and hydrophobic effect. The micro-lens arrays have uniform focusing function, smooth and real planar surface. The fabrication process showed good repeatability as well, fifty micro-lenses randomly selected form 9 × 9 miro-lens array with an average diameter of 333.28μm showed 1.1% variations. Also, the focal length, the surface roughness and optical property of the fabricated micro-lenses are measured, analyzed and proved satisfactory. The technique shows great potential for fabricating polymer micro-lens arrays with high flexibility, simple technological process and low production cost.

  16. Effect of historical earthquakes on pre-stressed anchor tie back diaphragm wall and on near-by building

    Directory of Open Access Journals (Sweden)

    Kamal Mohamed Hafez Ismail Ibrahim

    2013-04-01

    Full Text Available Pre-stressed tie back anchored diaphragm walls are considered one of the safest lateral supports which help in overall stability when there is a significant difference in land level between back and front of these walls. Permanent lateral supports to these walls are frequently represented by supporting it laterally with foundation and floor slabs of the building. In this paper a special study of one raw anchor diaphragm wall subjected to different earthquake dynamic loads will be presented. The wall retains an excavation of 9.5 m and supports laterally a near-by 5 floor building. Five historical strong motions with different fundamental frequencies are subjected on the wall. The wall displacement, straining actions, anchor extreme force and the influence of variation of anchor stiffness are calculated using a dynamic Plaxis finite element program. The soil is considered as elasto-plastic material and represented using Mohr–Coulomb criteria, the wall and the anchor are considered to behave elastically. Prescribed displacement at the lower bottom boundary represents the earthquake motion. Far left and right absorbent boundaries are assumed to prevent dynamic wave reflection. Four static phases representing construction procedure and one dynamic loading phase are considered. It is found that the straining actions of different historical earthquakes match in shape with each other, the only change is in the amplitude which is affected by earthquake fundamental frequency and its intensity. The maximum dynamic lateral displacement of the wall is at its free top. The near-by building shows a differential settlement towards the wall which causes a change in the sign and amplitude of the straining actions. Increasing the stiffness of anchor was also studied and it was found that it reduces too much the maximum dynamic top wall lateral displacement.

  17. Morfofisiologia da inervação do diafragma de ovinos Morphophysiology of diaphragm innervation in sheep

    Directory of Open Access Journals (Sweden)

    Ana E.F. de Almeida

    2008-09-01

    Full Text Available Foram estudados em 30 diafragmas de ovinos da raça Santa Inês, a origem, a divisão e a distribuição dos nervos frênicos direito e esquerdo (Fde e a participação de outros nervos na inervação do diafragma. Mediante fixação e dissecação das peças foi observado que os nervos frênicos (F originam-se a partir dos ramos ventrais do 5º (C5 e 6º (C6 nervos espinhais cervicais (Ec tanto à direita (46,67% como à esquerda (43,33%. Os F finalizam em tronco lombocostal e ramo esternal à direita (40,00% e em ramo lombar, costal e esternal à esquerda (36,68%. Os ramos lombares dos F inervam à esquerda (96,67% o pilar homolateral do diafragma e, à direita (50,00% fornecem filetes à veia caudal. Os ramos costais dos F ramificam à esquerda (90,00% e à direita (76,67% as regiões dorsal e ventral da pars costalis. Os ramos esternais dos F inervam à direita (100,00% e à esquerda (83,33% a pars sternalis e a região ventral da pars costalis do mesmo lado. Os nervos intercostais (VIII ao XII pares, 63,33% contribuem na inervação do diafragma de ovinos da raça Santa Inês.Thirty diaphragms of sheep of Santa Inês breed were studied regarding their origin, division and arrangement of the right and left phrenic nerves (Fde, and the participation of other nerves in the innervation of the diaphragm. By fixing and dissecting pieces, it was found that phrenic nerves (F frequently come from the ventral branches of the 5th (C5 and 6th (C6 cervical spinal nerves (Ec, at right (46.67% and at left (43.33%. The F often form a lumbocostal trunk, sternal branches at right (40.00% and lumbar, costal and esternal branches at left (36.68%. The lumbar branches of F innervate frequently at left (96.67% the homolateral pillar of the diaphragma, and at right (50.00% they give fillets to Vena cava caudalis. The costal branches of the F innervate at left (90.00% and at right (76.66% the dorsal and ventral regions of the pars costalis. The sternal branches of

  18. Combined transarterial chemoembolization of the right inferior phrenic artery and radiofrequency ablation for small hepatocellular carcinoma near the diaphragm: its efficacy and safety.

    Science.gov (United States)

    Hyun, Dongho; Cho, Sung Ki; Shin, Sung Wook; Park, Kwang Bo; Lee, Sang Yub; Park, Hong Suk; Choo, Sung Wook; Do, Young Soo

    2018-02-28

    The purpose of the study is to report the efficacy and safety of combined transarterial chemoembolization (TACE) of the right inferior phrenic artery (IPA) and radiofrequency ablation (RFA) for small hepatocellular carcinoma (HCC) near the diaphragm supplied by the right IPA. From July 2009 through April 2015, 11 patients with small (≤ 3 cm) HCC near the diaphragm, which was infeasible for ultrasound-guided RFA and supplied by the right IPA, received TACE of the right IPA and subsequent RFA in one session. The safety and therapeutic efficacy, including technique effectiveness and local tumor progression (LTP), were evaluated. Technique effectiveness was achieved in all the 11 patients (100%). During average follow-up period of 39.2 months (range 13-89 months), LTP occurred in none of the 11 patients. There were twelve minor complications in eight patients, including right shoulder pain (n = 4), right pleural effusion (n = 2), diaphragmatic thickening (n = 2), transient lung change (n = 2), subsegmental intrahepatic bile duct stricture (n = 1), and subsegmental hepatic infarction (n = 1). No major complications were encountered CONCLUSION: Combined TACE of the right IPA and RFA can be a safe and effective treatment for small HCC near the diaphragm that is supplied by the right IPA.

  19. Molecular Weiss domain polarization in piezoceramics to diaphragm, cantilever and channel construction in low-temperature-cofired ceramics for micro-fluidic applications

    International Nuclear Information System (INIS)

    Khanna, P.K.; Ahmad, S.; Grimme, R.

    2005-01-01

    This paper presents the efforts made to study the process of comminution to Weiss domain polarization and phase transition in piezoceramics together with the versatility of low-temperature-cofired ceramics-based devices and components for their ready adoption for typical applications in the area of micro-fluidics. A conceptual micro-fluidic module has been presented and few unit entities necessary for its realization have been described. The purpose of these entities is to position the sensors and actuators by using piezoelectric materials. Investigations are performed to make useful constructions like diaphragms and cantilevers for laying the sensing elements, cavities for burying the electronic chip devices, and channels for fluid transportation. In order to realize these constructions, the basic step involves machining of circular, straight line, rectangular and square-shaped structure in the green ceramic tapes followed by lamination and firing with post-machining in some cases. The diaphragm and cavity includes one or more un-machined layer stacked together with several machined layers with rectangular or square slits. The cantilever is an extension of the diaphragm creation process with inclusion of a post-machining step. The channel essentially consists of a machined green ceramic layer sandwiched between an un-machined and a partially machined layer. The fabrication for all the above constructions has been exemplified and the details have been discussed

  20. Expression of relaxin receptor LRG7, canine relaxin, and relaxin-like factor in the pelvic diaphragm musculature of dogs with and without perineal hernia.

    Science.gov (United States)

    Merchav, Ronit; Feuermann, Yonatan; Shamay, Avi; Ranen, Eyal; Stein, Uri; Johnston, Dudley E; Shahar, Ron

    2005-01-01

    To compare the expression of canine relaxin, relaxin-like factor (RLF), and relaxin receptors within the muscles of the pelvic diaphragm of dogs with perineal hernia (PH) and clinically normal dogs. In vivo comparative study. Fifteen client-owned intact male dogs with PH were studied. Four mature intact male dogs with no evidence of perineal pathology served as controls. Biopsy samples from the levator ani, coccygeus, and internal obturator muscles were obtained. RNA samples were reverse transcribed and analyzed by real-time PCR for the expression of canine relaxin receptor LRG7, relaxin, and RLF. Significantly higher expression levels of canine relaxin receptors occurred in the musculature of the pelvic diaphragm and internal obturator muscle in dogs with PH compared with normal dogs. Expression of canine RLF revealed no significant difference between dogs with PH and controls. The difference in the expression of canine relaxin between groups was not statistically significant. Relaxin receptor up-regulation occurs in the coccygeus, levator ani, and internal obturator muscles of dogs with PH. The higher expression of relaxin receptors within the muscles of the pelvic diaphragm in dogs with PH suggests that relaxin might play a role in the pathogenesis of PH. Atrophy of these muscles, which predisposes to PH, may be attributable to increased relaxin activity.

  1. Analysis of the reasons for failures of the 1500 MW turbines HP diaphragms on the EDF N4 units. Implementation of a solution

    International Nuclear Information System (INIS)

    Franc, J. C.; Franconville, M.

    2002-01-01

    The full text follows. Diaphragms are major components of an impulse type steam turbine since they hold the fixed blades which allow part of the steam expansion (the other part being on the moving blades mounted on the rotor) The 4 impulse type 1500 MW nuclear steam turbines, from the EDF N4 program,were commissioned in 1996 on the CHOOZ and then CIVAUX plants.The diaphragms, located in the HP(high pressure) part of these turbines, have shown signs of failures very soon, due to a cracking of assembly welds,which is dangerous for the machines integrity. These failures questioned a construction mode which had been highly experienced previously. A large campaign of inspections and tests was carried out to feature the ways of failure,on site or in the factory during manufacturing.Site measurements combined with numerical simulations allowed to define excitations, harmful to these components,during operation. Temporary solutions were applied in order to allow immediate restart of the plants.In parallel,a modification of the diaphragms design and assembly method was studied and applied to withstand the various operating stresses. (author)

  2. Numerical simulation on flow field of nuclear safety grade 2 single-seat pneumatic diaphragm control valve

    International Nuclear Information System (INIS)

    Zhong Yun; Zhang Jige; Wang Dezhong; Shi Jianzhong

    2010-01-01

    The Computational Fluid Dynamics (CFD) method is employed to simulate numerically the steady flow and transient flow under variable openings of the nuclear safety grade 2 single-seat pneumatic diaphragm control valve, which is a sleeve valve. The steady simulations under rated condition tells that there is a large amount of vortex in the valve seat necking and around the valve cone, which leads to a much greater flow impact on the head of the valve cone and uneven pressure distribution on spool face. More consideration should be taken on the characteristics of the valve cone accordingly, when designing a valve of this kind. Then the transient flow under 100% and 40% openings is simulated numerically on the basis of steady simulations. The pulsation of the pressure magnitude at the points with large vorticity, in the valve seat necking and around the valve cone, is monitored. The main pulsation frequencies differ from the low natural frequencies of the model, which means that it is safe from leading to structural resonance. (authors)

  3. Loss of cIAP1 attenuates soleus muscle pathology and improves diaphragm function in mdx mice

    Science.gov (United States)

    Enwere, Emeka K.; Boudreault, Louise; Holbrook, Janelle; Timusk, Kristen; Earl, Nathalie; LaCasse, Eric; Renaud, Jean-Marc; Korneluk, Robert G.

    2013-01-01

    The cellular inhibitor of apoptosis 1 (cIAP1) protein is an essential regulator of canonical and noncanonical nuclear factor κB (NF-κB) signaling pathways. NF-κB signaling is known to play important roles in myogenesis and degenerative muscle disorders such as Duchenne muscular dystrophy (DMD), but the involvement of cIAP1 in muscle disease has not been studied directly. Here, we asked whether the loss of cIAP1 would influence the pathology of skeletal muscle in the mdx mouse model of DMD. Double-mutant cIAP1−/−;mdx mice exhibited reduced muscle damage and decreased fiber centronucleation in the soleus, compared with single-mutant cIAP1+/+;mdx mice. This improvement in pathology was associated with a reduction in muscle infiltration by macrophages and diminished expression of inflammatory cytokines such as IL-6 and tumor necrosis factor-α. Furthermore, the cIAP1−/−;mdx mice exhibited reduced serum creatine kinase, and improved exercise endurance associated with improved exercise resilience by the diaphragm. Mechanistically, the loss of cIAP1 was sufficient to drive constitutive activation of the noncanonical NF-κB pathway, which led to increased myoblast fusion in vitro and in vivo. Collectively, these results show that the loss of cIAP1 protects skeletal muscle from the degenerative pathology resulting from systemic loss of dystrophin. PMID:23184147

  4. A compact and facile microfluidic droplet creation device using a piezoelectric diaphragm micropump for droplet digital PCR platforms.

    Science.gov (United States)

    Okura, Naoaki; Nakashoji, Yuta; Koshirogane, Toshihiro; Kondo, Masaki; Tanaka, Yugo; Inoue, Kohei; Hashimoto, Masahiko

    2017-10-01

    We have exploited a compact and facile microfluidic droplet creation device consisting of a poly(dimethylsiloxane) microfluidic chip possessing T-junction channel geometry, two inlet reservoirs, and one outlet reservoir, and a piezoelectric (PZT) diaphragm micropump with controller. Air was evacuated from the outlet reservoir using the PZT pump, reducing the pressure inside. The reduced pressure within the outlet reservoir pulled oil and aqueous solution preloaded in the inlet reservoirs into the microchannels, which then merged at the T-junction, successfully forming water-in-oil emulsion droplets at a rate of ∼1000 per second with minimal sample loss. We confirmed that the onset of droplet formation occurred immediately after turning on the pump (<1 s). Over repeated runs, droplet formation was highly reproducible, with droplet size purity (polydispersity, <4%) comparable to that achieved using other microfluidic droplet preparation techniques. We also demonstrated single-molecule PCR amplification in the created droplets, suggesting that the device could be used for effective droplet digital PCR platforms in most laboratories without requiring great expense, space, or time for acquiring technical skills. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Influence of some mononucleotides and their corresponding nucleosides on the metabolism of carbohydrates in the isolated rat diaphragm muscle

    Science.gov (United States)

    Beloff-Chain, Anne; Betto, P.; Bleszynski, W.; Catanzaro, Raffaella; Chain, E. B.; Dmitrovskii, A. A.; Longinotti, L.; Pocchiari, F.

    1965-01-01

    1. The influence of ATP on glucose metabolism was studied in the isolated rat diaphragm; it was shown that ATP increases the oxidation of glucose and the aerobic conversion of glucose into lactate, whereas it decreases glycogen synthesis. There was no influence of ATP on the anaerobic formation of lactate from glucose. 2. A maximum effect of ATP on the oxidation of glucose (about 160% increase) was obtained in the presence of 10mm-ATP; in the presence of 2mm-ATP the effect was about 65%, and was approximately constant from 10 to 90min. incubation period. 3. In a phosphate-free tris-buffered medium the oxidation of glucose was considerably decreased, but the percentage stimulation by ATP was about the same as in a phosphate-buffered medium. 4. ATP was shown to increase the oxidation of fructose, glucose 6-phosphate, glucose 1-phosphate, fructose 1,6-diphosphate and, to a much smaller extent, pyruvate. 5. ADP stimulated the oxidation of glucose to the same extent as ATP at a concentration of 2mm and the effect with AMP was only slightly less; IMP and adenosine had only a small stimulatory effect at this concentration, whereas inosine had no effect. PMID:16749165

  6. Influence of diaphragm wall installation in overconsolidated sandy clays on in situ stress disturbance and resulting wall deformations

    Directory of Open Access Journals (Sweden)

    Truty Andrzej Adam

    2016-09-01

    Full Text Available Numerical modeling of deep excavations becomes a standard practice in modern geotechnical engineering. A detailed numerical model for a given case is able to reproduce major effects of soil-structure interaction by taking into account any kind of drainage conditions, strong stiffness variation due to effective stress and strain changes, creep and cracking, when reinforced concrete is used as a structural material, but also interface effects between subsoil and structure. Calibrating soil constitutive models is one of the most difficult tasks and due to several sources of uncertainty there is no one unique set of the data that should be used in numerical predictions. Lack or incompleteness of experimental data, significant mismatch between laboratory and field tests is an another source of difficulty. Contrary to several simplified methods, that are usually limited to two dimensions, numerical models allow a full 3D analysis in which many simplifications can be eliminated. This paper is devoted to the problem of in situ stress disturbance caused by diaphragm wall installation in overconsolidated quaternary sandy clays and its influence on final wall deformations.

  7. Successful Reinnervation of the Diaphragm After Intercostal to Phrenic Nerve Neurotization in Patients With High Spinal Cord Injury.

    Science.gov (United States)

    Nandra, Kulvir S; Harari, Martin; Price, Thea P; Greaney, Patrick J; Weinstein, Michael S

    2017-08-01

    Our objective in this study was to extend diaphragmatic pacing therapy to include paraplegic patients with high cervical spinal cord injuries between C3 and C5. Diaphragmatic pacing has been used in patients experiencing ventilator-dependent respiratory failure due to spinal cord injury as a means to reduce or eliminate the need for mechanical ventilation. However, this technique relies on intact phrenic nerve function. Recently, phrenic nerve reconstruction with intercostal nerve grafting has expanded the indications for diaphragmatic pacing. Our study aimed to evaluate early outcomes and efficacy of intercostal nerve transfer in diaphragmatic pacing. Four ventilator-dependent patients with high cervical spinal cord injuries were selected for this study. Each patient demonstrated absence of phrenic nerve function via external neck stimulation and laparoscopic diaphragm mapping. Each patient underwent intercostal to phrenic nerve grafting with implantation of a phrenic nerve pacer. The patients were followed, and ventilator dependence was reassessed at 1 year postoperatively. Our primary outcome was measured by the amount of time our patients tolerated off the ventilator per day. We found that all 4 patients have tolerated paced breathing independent of mechanical ventilation, with 1 patient achieving 24 hours of tracheostomy collar. From this study, intercostal to phrenic nerve transfer seems to be a promising approach in reducing or eliminating ventilator support in patients with C3 to C5 high spinal cord injury.

  8. On the appearance of acetylcholine receptors in denervated rat diaphragm, and its dependence on nerve stump length

    International Nuclear Information System (INIS)

    Uchitel, O.; Robbins, N.

    1978-01-01

    Acetylcholine (ACh) sensitivity and extrajunctional receptor distribution of the rat diaphragm were closely monitored during the early period following denervation. Both contracture in response to 10 μg/ml of ACh and extrajunctional binding of [ 125 I]alpha-bungarotoxin ([ 125 I]α-BTX) were first detectable 30 h after cutting the phrenic nerve in the thorax. If the nerve were cut more proximally, leaving a 3.5 cm distal nerve stump, the same level of ACh contracture and [ 125 I]α-BTX binding did not appear until 40 h after operation. This 10-h delay was far longer than the 3-h delay in transmission failure reportedly dependent on stump length. The earliest detectable extrajunctional [ 125 I]α-BTX binding appeared throughout the entire muscle fiber, and was not localized to the endplate region as would be expected if degeneration in the nerve terminal induced new receptors. However, later significant increases in [ 125 I]α-BTX binding at the endplate region could have resulted from such degeneration. All these results are consistent with neurotrophic regulation of muscle ACh receptors, working via a mechanism involving axonal transport. (Auth.)

  9. Contribution of direct actions of the oxime HI-6 in reversing soman-induced muscle weakness in the rat diaphragm

    Energy Technology Data Exchange (ETDEWEB)

    Alder, M.; Maxwell, D.M.; Filbert, M.G.; Deshpande, S.S.

    1994-12-31

    The actions of the bispyridinium oxime HI-6 ((4-AMINOCARBONYL) PYRIDINO-methoxymethyl- 2-(HYDROXYIMINO)METHYL- pyridinium dichloride) were investigated in vitro on rat phrenic nerve-hemidiaphragm preparations. Isometric twitch and tetanic tensions were elicited at 37 deg C with supramaximal nerve stimulation at frequencies of 20 and 50 Hz. To approximate normal respiration patterns, trials consisting of 30 successive 0.55 5 trains were alternated with 1.25 5 rest periods. Under control conditions, the above stimulation pattern generated tensions that were well maintained at both frequencies. In contrast, a marked depression of muscle tension was observed in diaphragms removed from rats administered 339 ug/kg soman (3 LD50) and tested in vitro. Addition of HI-6, 4 h after soman exposure, led to a nearly complete recovery of muscle tension at 20 Hz. At 50 Hz, muscle tensions still declined especially when trains were elicited at 1.25 and 3 5 intervals. The recovery by HI-6 observed in this study appears to be mediated by mechanisms unrelated to acetylcholinesterase reactivation since no increase of enzymatic activity was detected and the effect was reversed by a brief washout in oxime-free physiological solution. The results suggest that the direct action of HI-6 may play a role in restoring soman-induced diaphragmatic failure but this effect would be significant primarily under low use conditions.

  10. DiapHRaGM: A mnemonic to describe the work of breathing in patients with respiratory failure.

    Directory of Open Access Journals (Sweden)

    Aiman Tulaimat

    Full Text Available The assessment of the work of breathing in the definitions of respiratory failure is vague and variable.Identify a parsimonious set of signs to describe the work of breathing in hypoxemic, acutely ill patients.We examined consecutive medical ICU patients receiving oxygen with a mask, non-invasive ventilation, or T-piece. A physician inspected each patient for 10 seconds, rated the level of respiratory distress, and then examined the patient for vital signs and 17 other physical signs. We used the rating of distress as a surrogate for measuring the work of breathing, constructed three multivariate models to identify the one with the smallest number of signs and largest explained variance, and validated it with bootstrap analysis.We performed 402 observations on 240 patients. Respiratory distress was absent in 78, mild in 157, moderate in 107, and severe in 60. Respiratory rate, hypoxia, heart rate, and frequency of most signs increased as distress increased. Respiratory rate and hypoxia explained 43% of the variance in respiratory distress. Diaphoresis, gasping, and contraction of the sternomastoid explained an additional 28%. Heart rate, blood pressure, alertness, agitation, body posture, nasal flaring, audible breathing, cyanosis, tracheal tug, retractions, paradox, scalene or abdominal muscles contraction did not increase the explained variance in respiratory distress.Most of the variance is respiratory distress can be explained by five signs summarized by the mnemonic DiapHRaGM (diaphoresis, hypoxia, respiratory rate, gasping, accessory muscle. This set of signs may allow for efficient, standardized assessments of the work of breathing of hypoxic patients.

  11. Diaphragm and lung-preserving surgery with hyperthermic chemotherapy for malignant pleural mesothelioma: A 10-year experience.

    Science.gov (United States)

    Ambrogi, Marcello Carlo; Bertoglio, Pietro; Aprile, Vittorio; Chella, Antonio; Korasidis, Stylianos; Fontanini, Gabriella; Fanucchi, Olivia; Lucchi, Marco; Mussi, Alfredo

    2018-04-01

    The best surgical treatment for malignant pleural mesothelioma is still under a debate, but recent evidence points toward a less-invasive approach to reduce morbidity and mortality. We reported our 10-year experience of a limited surgical approach associated with hyperthermic intrathoracic chemotherapy (HITHOC). Between 2005 and 2014, patients with epithelioid or biphasic malignant pleural mesothelioma were treated with lung-diaphragm-pericardium-sparing pleurectomy associated with double-drug HITHOC; at least 3 cycles of adjuvant chemotherapy were then administered. The primary outcome examined was the feasibility of the procedure, whereas secondary outcomes were overall survival and disease-free interval. Among 49 patients, 41 were male. Median age was 68 years (35-76 years). Histology was epithelioid in 43 cases. Pathologic stage I, II, III, and IV occurred in 12, 14, 20, and 3 cases, respectively. No intraoperative complications or postoperative mortality occurred, whereas morbidity rate was 46.9%. Median hospital stay was 8 days (5-45 days). Actuarial median overall survival was 22 months and a 1-, 2-, and 5-year survival accounted for 79.6%, 45.7%, and 9.9%, respectively. Disease-free survival after surgery was 62%, 37.5%, and 18.5% at 1, 2, and 5 years, respectively. Risk factors analysis for overall survival confirmed a significant role for early stages, epithelioid histology, and fibrinogen serum levels. Cytoreductive surgery associated with HITHOC and adjuvant chemotherapy appears feasible and safe, with no mortality and low morbidity. Preserving lung and diaphragmatic function might warrant an acceptable long-term outcome. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  12. Ultrasonographic assessment of the diaphragm in chronic obstructive pulmonary disease patients: relationships with pulmonary function and the influence of body composition - a pilot study.

    Science.gov (United States)

    Smargiassi, Andrea; Inchingolo, Riccardo; Tagliaboschi, Linda; Di Marco Berardino, Alessandro; Valente, Salvatore; Corbo, Giuseppe Maria

    2014-01-01

    Skeletal muscle weakness with loss of fat-free mass (FFM) is one of the main systemic effects of chronic obstructive pulmonary disease (COPD). The diaphragm is also involved, leading to disadvantageous conditions and poor contractile capacities. We measured the thickness of the diaphragm (TD) by ultrasonography to evaluate the relationships between echographic measurements, parameters of respiratory function and body composition data. Thirty-two patients (23 males) underwent (1) pulmonary function tests, (2) echographic assessment of TD in the zone of apposition at various lung volumes, i.e. TD at residual volume (TDRV), TD at functional residual capacity (TDFRC) and TD at total lung capacity (TDTLC), and (3) bioelectrical body impedance analysis. The BMI and the BODE (BMI-Obstruction-Dyspnea-Exercise) index values were reported. TDRV, TDFRC and TDTLC measured 3.3, 3.6 and 6 mm, respectively, with good intraobserver reproducibility (0.97, 0.97 and 0.96, respectively). All the TDs were found to be related to FFM, with the relationship being greater for TDFRC (r(2) = 0.39 and p = 0.0002). With regard to lung volumes, inspiratory capacity (IC) was found to be closely related to TDTLC (r(2) = 0.42 and p = 0.0001). The difference between TDTLC and TDRV, as a thickening value (TDTLCRV), was closely related to FVC (r(2) = 0.34 and p = 0.0004) and to air-trapping indices (RV/TLC, FRC/TLC and IC/TLC): the degree of lung hyperinflation was greater and the TDTLCRV was less. Finally, we found a progressive reduction of both thicknesses and thickenings as the severity of IC/TLC increased, with a significant p value for the trend in both analyses (p = 0.02). Ultrasonographic assessment of the diaphragm could be a useful tool for studying disease progression in COPD patients, in terms of lung hyperinflation and the loss of FFM. © 2014 S. Karger AG, Basel.

  13. Investigation of piezoresistive effect in p-channel metal–oxide–semiconductor field-effect transistors fabricated on circular silicon-on-insulator diaphragms using cost-effective minimal-fab process

    Science.gov (United States)

    Liu, Yongxun; Tanaka, Hiroyuki; Umeyama, Norio; Koga, Kazuhiro; Khumpuang, Sommawan; Nagao, Masayoshi; Matsukawa, Takashi; Hara, Shiro

    2018-06-01

    P-channel metal–oxide–semiconductor field-effect transistors (PMOSFETs) with the 〈110〉 or 〈100〉 channel direction have been successfully fabricated on circular silicon-on-insulator (SOI) diaphragms using a cost-effective minimal-fab process, and their electrical characteristics have been systematically investigated before and after the SOI diaphragm formation. It was found that almost the same subthreshold slope (S-slope) and threshold voltage (V t) are observed in the fabricated PMOSFETs before and after the SOI diaphragm formation, and they are independent of the channel direction. On the other hand, significant variations in drain current were observed in the fabricated PMOSFETs with the 〈110〉 channel direction after the SOI diaphragm formation owing to the residual mechanical stress-induced piezoresistive effect. It was also confirmed that electrical characteristics of the fabricated PMOSFETs with the 〈100〉 channel direction are almost the same before and after the SOI diaphragm formation, i.e., not sensitive to the mechanical stress. Moreover, the drain current variations at different directions of mechanical stress and current flow were systematically investigated and discussed.

  14. Determination of the activity concentration of a 238 Pu solution by the defined solid angle method utilizing a novel dual diaphragm-detector assembly.

    Science.gov (United States)

    Aguiar, Julio C; Galiano, Eduardo; Arenillas, Pablo

    2005-08-01

    The activity concentration of a (238)Pu solution was measured by the determined solid angle method employing a novel dual diaphragm-detector assembly, which has been previously described. Due to the special requirements of the detector, a new type of source holder was developed, which consisted of sandwiching the radioisotope between two organic films called VYNS. It was experimentally demonstrated that the VYNS films do not absorb alpha particles, but reduce their energy by an average of 22 keV.A mean activity concentration for (238)Pu of 359.10+/-0.8 kBq/g was measured.

  15. Determination of the activity concentration of a {sup 238}Pu solution by the defined solid angle method utilizing a novel dual diaphragm-detector assembly

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Julio C. [Departamento de Postgrado, Universidad Tecnologica Nacional, Buenos Aires (Argentina); Galiano, Eduardo [Departament of Physics, Laurentian University, Sudbury, Ont. P3E 2C6 (Canada)]. E-mail: egalianoriveros@laurentian.ca; Arenillas, Pablo [Comision Nacional de Energia Atomica, CAE, Laboratorio de Metrologia de Radioisotopos, Buenos Aires (Argentina)

    2005-08-01

    The activity concentration of a {sup 238}Pu solution was measured by the determined solid angle method employing a novel dual diaphragm-detector assembly, which has been previously described. Due to the special requirements of the detector, a new type of source holder was developed, which consisted of sandwiching the radioisotope between two organic films called VYNS. It was experimentally demonstrated that the VYNS films do not absorb {alpha} particles, but reduce their energy by an average of 22keV.A mean activity concentration for {sup 238}Pu of 359.10+/-0.8kBq/g was measured.

  16. Determination of the activity concentration of a 238Pu solution by the defined solid angle method utilizing a novel dual diaphragm-detector assembly

    International Nuclear Information System (INIS)

    Aguiar, Julio C.; Galiano, Eduardo; Arenillas, Pablo

    2005-01-01

    The activity concentration of a 238 Pu solution was measured by the determined solid angle method employing a novel dual diaphragm-detector assembly, which has been previously described. Due to the special requirements of the detector, a new type of source holder was developed, which consisted of sandwiching the radioisotope between two organic films called VYNS. It was experimentally demonstrated that the VYNS films do not absorb α particles, but reduce their energy by an average of 22keV.A mean activity concentration for 238 Pu of 359.10+/-0.8kBq/g was measured

  17. The clinical implications of severe low rib fracture in the management of diaphragm injury: A Case Control Study.

    Science.gov (United States)

    Kim, Seongyup; Choi, Woo Jin; Lee, Kawng Ho; Byun, Chun Sung; Bae, Keum Seok; Park, Il Hwan

    2017-06-01

    The objective of this study was to analyze the differences in clinical presentation and characteristics with regard to diaphragmatic injury between blunt trauma patients with severe low rib fractures and those without severe low rib fractures. The medical records of all patients with diaphragmatic injuries who were surgically treated at this level I trauma center, between January 2004 and December 2016 were reviewed. Patient notes, radiologic findings, and operative reports were evaluated. All of the diaphragmatic injuries were confirmed based on the operative findings. Rib fracture with displacement between the ends of the fracture of more than half the width of the fractured rib on computed tomography was classified as 'severe rib fracture'. Patients were categorized into 2 groups and analyzed: those who had more than one severe rib fracture in low ribs on the ipsilateral side of the diaphragm injury (Severe group), and those with no severe rib fracture (Non-severe group). Delayed diagnosis of diaphragmatic injury was more frequent in the Severe group than in the Non-severe group (81.8% vs 36.8%, p-value = 0.026). With regard to initial indications for operation, intrathoracic visceral herniation was more frequent in the Non-severe group (78.9% vs 18.2%, p-value = 0.002), while hemothorax was more frequent in the Severe group (63.6% vs 5.3%, p-value = 0.001). Central type diaphragmatic laceration was more frequent in the Non-severe group than in the Severe group (78.9% vs 18.2%, p-value = 0.002). The diameter of diaphragmatic injury was larger in the Non-severe group than in the Severe group (9.70 ± 4.10 cm vs 4.80 ± 3.60 cm, p-value = 0.004). The results of this study imply that a low threshold for thoracotomy or laparotomy should be considered in blunt trauma patients with severe low rib fractures for the purpose of hidden diaphragmatic injury detection and management. Copyright © 2017. Published by Elsevier Ltd.

  18. Integrated electrochromic aperture diaphragm

    Science.gov (United States)

    Deutschmann, T.; Oesterschulze, E.

    2014-05-01

    In the last years, the triumphal march of handheld electronics with integrated cameras has opened amazing fields for small high performing optical systems. For this purpose miniaturized iris apertures are of practical importance because they are essential to control both the dynamic range of the imaging system and the depth of focus. Therefore, we invented a micro optical iris based on an electrochromic (EC) material. This material changes its absorption in response to an applied voltage. A coaxial arrangement of annular rings of the EC material is used to establish an iris aperture without need of any mechanical moving parts. The advantages of this device do not only arise from the space-saving design with a thickness of the device layer of 50μm. But it also benefits from low power consumption. In fact, its transmission state is stable in an open circuit, phrased memory effect. Only changes of the absorption require a voltage of up to 2 V. In contrast to mechanical iris apertures the absorption may be controlled on an analog scale offering the opportunity for apodization. These properties make our device the ideal candidate for battery powered and space-saving systems. We present optical measurements concerning control of the transmitted intensity and depth of focus, and studies dealing with switching times, light scattering, and stability. While the EC polymer used in this study still has limitations concerning color and contrast, the presented device features all functions of an iris aperture. In contrast to conventional devices it offers some special features. Owing to the variable chemistry of the EC material, its spectral response may be adjusted to certain applications like color filtering in different spectral regimes (UV, optical range, infrared). Furthermore, all segments may be switched individually to establish functions like spatial Fourier filtering or lateral tunable intensity filters.

  19. Thermo active piles and diaphragm walls building process and thermal response test; Pilotes y pantallas termoactivas. Proceso constructivo y caracterizacion termica

    Energy Technology Data Exchange (ETDEWEB)

    Mazariegos, A.; Anton, L. C.; Valle, R.; Urchueguia, J.; Quilis, S.; Martinez, S.; Magraner, T.

    2009-07-01

    Thermo active foundation technology uses building foundation piles diaphragm wall slabs as ground heat exchangers to provide building with heating and cooling. This type of foundation is based on the use of the ground temperature to enhance the heat pump coefficient of performance (COP). In this kind of structures, the heat exchange can be done through a closed circuit installed on the reinforced of the foundation. This closed circuit is made up of HDPE pipes geothermal probes, through which water or brine circulates producing a heat exchange between this fluid and the ground. this fluid is led to a geothermal heat pump GHP, generating the energy required for air-conditioning a building. ENERGESIS, leading company in the air-conditioning field using geothermal energy and RADIO KRONSA, leading company in the engineering field of soil and subsoil, with the collaboration of the Universidad Politecnica de Valencia (UPV) and the Escuela Universitaria de Ingenieria Tecnica de Obras Publicas (UPM), have developed an action line to design and implement saving energy facilities by using geothermal energy associated with the foundations. A series of tests at work have been done in order to have a procedure to implement the thermal response of thermo active piles and diaphragm walls. (Author) 7 refs.

  20. [Visual rehabilitation of patients with large post-traumatic defects of the anterior eye segment through iris-lens diaphragm implantation].

    Science.gov (United States)

    Khodzhaev, N S; Sobolev, N P; Mushkova, I A; Izmaylova, S B; Karimova, A N

    The diversity of methodological approaches and lack of pathogenetically reasonable tactics for patients with combined ocular injuries became the basis for the development and systematization of surgical rehabilitation stages of patients, in whom post-traumatic cataract is combined with post-traumatic aniridia and corneal scarring. to construct a visual rehabilitation approach to patients with post-traumatic defects of the anterior eye segment following optical-reconstructive surgery that involved implantation of an iris-lens diaphragm (ILD). We have analyzed 80 reconstructive cases with ILD implantation in patients with post-traumatic aniridia and corneal damage. These patients constituted the first study group (Group 1). We have also investigated 58 eyes with residual ametropy and stable visual function 1 year after ILD implantation before and after conducting a laser keratorefractive surgery. These patients were assigned to the second study group (Group 2). Rehabilitation approach to patients after anterior segment injuries that has been proposed allows to achieve high clinical and functional results and reduce the risk of intra- and postoperative complications. The proposed approach to patients after optical-reconstructive surgery with iris-lens diaphragm implantation followed by keratorefractive surgery is an effective method of visual rehabilitation of anterior eye segment post-traumatic defects.

  1. N-acetylcysteine fails to modulate the in vitro function of sarcoplasmic reticulum of diaphragm in the final phase of fatigue.

    Science.gov (United States)

    Mishima, T; Yamada, T; Matsunaga, S; Wada, M

    2005-07-01

    In the present study, we tested the hypothesis whether N-acetylcysteine (NAC), a non-specific antioxidant, might influence fatigue by modulating Ca2+-handling capacity by the sarcoplasmic reticulum (SR). In the presence (10 mm) or absence of NAC, bundles of rat diaphragm were stimulated with tetanic trains (350 ms, 30-40 Hz) at 1 train every 2 s for 300 s. SR functions, as assessed by SR Ca2+-uptake and release rates and SR Ca2+-ATPase activity, were measured in vitro on muscle homogenates. Following the 300-s stimulation, the force developed by NAC-treated muscles is approximately 1.8-fold higher (P depression in SR function (P < 0.05). Despite the differing degrees of fatigue between NAC-treated and non-treated muscles, SR functions in these muscles were reduced to similar extents. These results suggest that modulation of SR function measured in vitro may not be a major contributor to inhibition of diaphragmic fatigue with antioxidant, at least, in the final phase of fatigue where force output is remarkably reduced.

  2. Safety and efficacy of diaphragm pacing in patients with respiratory insufficiency due to amyotrophic lateral sclerosis (DiPALS): a multicentre, open-label, randomised controlled trial.

    Science.gov (United States)

    2015-09-01

    Non-invasive ventilation is part of the standard of care for treatment of respiratory failure in patients with amyotrophic lateral sclerosis (ALS). The NeuRx RA/4 Diaphragm Pacing System has received Humanitarian Device Exemption approval from the US Food and Drug Administration for treatment of respiratory failure in patients with ALS. We aimed to establish the safety and efficacy of diaphragm pacing with this system in patients with respiratory muscle weakness due to ALS. We undertook a multicentre, open-label, randomised controlled trial at seven specialist ALS and respiratory centres in the UK. Eligible participants were aged 18 years or older with laboratory supported probable, clinically probable, or clinically definite ALS; stable riluzole treatment for at least 30 days; and respiratory insufficiency. We randomly assigned participants (1:1), via a centralised web-based randomisation system with minimisation that balanced patients for age, sex, forced vital capacity, and bulbar function, to receive either non-invasive ventilation plus pacing with the NeuRx RA/4 Diaphragm Pacing System or non-invasive ventilation alone. Patients, carers, and outcome assessors were not masked to treatment allocation. The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Analysis was by intention to treat. This trial is registered, ISRCTN number 53817913. Between Dec 5, 2011, and Dec 18, 2013, we randomly assigned 74 participants to receive either non-invasive ventilation alone (n=37) or non-invasive ventilation plus diaphragm pacing (n=37). On Dec 18, 2013, the Data Monitoring and Ethics Committee (DMEC) recommended suspension of recruitment on the basis of overall survival figures. Randomly assigned participants continued as per the study protocol until June 23, 2014, when the DMEC advised discontinuation of pacing in all patients. Follow-up assessments continued until the planned end of the study in December, 2014. Survival

  3. Electromyographic activity of the diaphragm during neostigmine or sugammadex-enhanced recovery after neuromuscular blockade with rocuronium: a randomised controlled study in healthy volunteers.

    Science.gov (United States)

    Schepens, Tom; Cammu, Guy; Saldien, Vera; De Neve, Nikolaas; Jorens, Philippe G; Foubert, Luc; Vercauteren, Marcel

    2015-01-01

    The use of neuromuscular blocking agents has been associated with severe postoperative respiratory morbidity. Complications can be attributed to inadequate reversal, and reversal agents may themselves have adverse effects. To compare the electromyographic activity of the diaphragm (EMGdi) during recovery from neuromuscular blockade using neostigmine and sugammadex. The hypothesis was that there would be better neuromuscular coupling of the diaphragm when sugammadex was used. A randomised, controlled, parallel-group, single-centre, double-blinded study. District general hospital in Belgium. Twelve healthy male volunteers. Individuals were anaesthetised with propofol and remifentanil. After rocuronium 0.6 mg kg, a transoesophageal electromyography (EMG) recorder was inserted. For reversal of neuromuscular blockade, volunteers received sugammadex 2 mg kg (n = 6) or neostigmine 70 μg kg (n = 6). EMGdi, airway pressure and flow were continuously measured during weaning from the ventilator until tracheal extubation. Arterial blood gas samples were obtained for PaO2 and PaCO2 analysis at the first spontaneous breathing attempt and after tracheal extubation. During weaning, 560 breaths were retained for analysis. The median (95% CI) peak EMGdi was 1.1 (0.9 to 1.5) μV in the neostigmine group and 1.6 (1.3 to 1.9) μV in the sugammadex group (P sugammadex group (P = 0.008). The median (95% CI) tidal volume was 287 (256 to 335) ml after neostigmine and 359 (313 to 398) ml after sugammadex (P = 0.013). The median (95% CI) PaO2 immediately after extubation was 30.5 (22.8 to 37.1) kPa after sugammadex vs. 20.7 (12.9 to 27.5) kPa after neostigmine (P = 0.03). EMGdi, tidal volume and PaO2 following tracheal extubation were increased after sugammadex compared with neostigmine, reflecting diaphragm-driven inspiration after sugammadex administration. Sugammadex may free more diaphragmatic acetylcholine receptors than neostigmine, which has an

  4. An analysis of plasticity in the rat respiratory system following cervical spinal cord injury and the application of nanotechnology to induce or enhance recovery of diaphragm function

    Science.gov (United States)

    Walker, Janelle

    Second cervical segment spinal cord hemisection (C2Hx) results in ipsilateral hemidiaphragm paralysis. However, the intact latent crossed phrenic pathway can restore function spontaneously over time or immediately following drug administration. WGA bound fluorochromes were administered to identify nuclei associated with diaphragm function in both the acute and chronic C2Hx models. WGA is unique in that it undergoes receptor mediated endocytosis and is transsynaptically transported across select physiologically active synapses. Comparison of labeling in the acutely injured to the chronically injured rat provided an anatomical map of spinal and supraspinal injury induced synaptic plasticity. The plasticity occurs over time in the chronic C2Hx model in an effort to adapt to the loss of hemidiaphragm function. Utilizing the selectivity of WGA, a nanoconjugate was developed to target drug delivery to nuclei involved in diaphragm function post C2Hx in an effort to restore lost function. Theophylline was selected due to its established history as a respiratory stimulant. Theophylline was attached to gold nanoparticles by a transient bond designed to degrade intracellularly. The gold nanoparticles were then permanently attached to WGA-HRP. Following intradiaphragmatic injection, the WGA portion was identified in the ipsilateral phrenic nuclei and bilaterally in the rVRGs. The location of WGA should reflect the location of the AuNP since the peptide bond between them is permanent. The effectiveness of the nanoconjugate was verified with EMG analysis of the diaphragm and recordings from the phrenic nerves. All doses administered in the acute C2Hx model resulted in resorted hemidiaphragm and phrenic nerve activity. A dose of 0.14mg/kg had a significantly higher percent recovery on day 3, whereas 0.03mg/kg was significantly higher on day 14. The change in most effective dose over time is likely due to the availability or concentration of the drug and location of drug release

  5. Thoracic meningocele in lumbo-costo-vertebral syndrome in a child: possible enlargement with repeated motion by anchoring to the diaphragm.

    Science.gov (United States)

    Wataya, Takafumi; Horikawa, Kyohei; Kitagawa, Masashi; Tashiro, Yuzuru

    2016-08-01

    Lumbo-costo-vertebral syndrome (LCVS) is a rare disorder in children that is characterized by hemivertebrae, congenital absence of ribs, meningocele, and hypoplasia of the truncal and abdominal wall presenting as a congenital lumbar hernia. An otherwise healthy 12-month-old girl was referred to the authors' hospital with soft swelling on her left middle back; scoliosis had been present since birth. Imaging revealed a thoracic meningocele, ectopia of the spleen suggesting lumbar hernia, multiple anomalies of the thoracic vertebral columns, and defects of the ribs; thus, LCVS was diagnosed. Surgical observation revealed that the meningocele was firmly anchored to part of the diaphragm, which created stretching tension in the meningocele continuously with exhalation. Once detached, the meningocele shrank spontaneously and never developed again after cauterization. In this case, continuous or pulsatile pressure in the presence of a vertebral defect was thus considered to be an important factor for formation of the thoracic meningocele.

  6. A high performance micro-pressure sensor based on a double-ended quartz tuning fork and silicon diaphragm in atmospheric packaging

    International Nuclear Information System (INIS)

    Cheng, Rongjun; Li, Cun; Zhao, Yulong; Li, Bo; Tian, Bian

    2015-01-01

    A resonant micro-pressure sensor based on a double-ended quartz tuning fork (DEQTF) and bossed silicon diaphragm in atmospheric packaging is presented. To achieve vacuum-free packaging with a high quality factor, the DEQTF is designed to resonate in an anti-phase vibration mode in a plane that is under the effect of slide-film damping. The feasibility is demonstrated by theoretical analysis and a finite element simulation. The dimensions of the DEQTF and diaphragm are optimized in accordance with the principles of improving sensitivity and minimizing energy dissipation. The sensor chip is fabricated using quartz and silicon micromachining technologies, and simply packaged in a stainless steel shell with standard atmosphere. The experimental setup is established for the calibration, where an additional sensor prototype without a pressure port is introduced as a frequency reference. By detecting the frequency difference of the tested sensor and reference sensor, the influences of environmental factors such as temperature and shocks on measuring accuracy are eliminated effectively. Under the action of a self-excitation circuit, static performance is obtained. The sensitivity of the sensor is 299 kHz kPa −1 in the operating range of 0–10 kPa at room temperature. Testing results shows a nonlinearity of 0.0278%FS, a hysteresis of 0.0207%FS and a repeatability of 0.0375%FS. The results indicate that the proposed sensor has favorable features, which provides a cost-effective and high-performance approach for low pressure measurement. (paper)

  7. [Postoperative ultrasound biomicroscopic evaluation of the tangible position of black diaphragm posterior chamber lenses in congenital and traumatic aniridia in comparison with gonioscopy].

    Science.gov (United States)

    Schweykart, N; Reinhard, T; Engelhardt, S; Sundmacher, R

    1999-06-01

    Ultrasound biomicroscopy (UBM) allows to determine the haptic position of posterior chamber lenses (PCL) in relation to adjacent structures. In transsclerally sutured PCLs, the comparison between intraoperatively endoscopically and postoperatively localized haptic positions via UBM showed a correspondence of only 81%. The different localisation of 19% of the examined haptic positions was explained with postoperative dislocation without any proof for this assumption. The purpose of this study therefore was the correlation of UBM results with simultaneously determined haptic positions via gonioscopy in aniridia after black diaphragm PCL implantation. The haptic positions of black diaphragm PCL implants in 20 patients with congenital and 13 patients with traumatic aniridia were determined via UBM (50-MHz-probe) and gonioscopy 44.4 (6-75) months postoperatively. 39/66 haptic positions could be localized in gonioscopy as well as in UBM. 38 haptics (97.4%) showed the same position in both examination techniques. Determination of the haptic position through one of the two examination techniques was impossible in 27/66 haptics (11 haptics in gonioscopy, 16 haptics in UBM). Reasons for this were primarily haptic position behind iris remnants and corneal opacities in gonioscopy and scarring of the ciliary body in UBM. The validity of UBM in localization of PCLs was confirmed gonioscopically, which also confirms our prior assumption of postoperative displacement of IOL-haptics after transscleral suturing in about 20% of cases. Scarring of the ciliary body was the most important obstacle in the determination of PCL haptic positions in relation to adjacent structures.

  8. Consistent use of a combination product versus a single product in a safety trial of the diaphragm and microbicide in Harare, Zimbabwe.

    Science.gov (United States)

    van der Straten, Ariane; Moore, Jie; Napierala, Sue; Clouse, Kate; Mauck, Christine; Hammond, Nii; Padian, Nancy

    2008-06-01

    We examined the use and acceptability of a combination product (diaphragm and gel) compared to a single product (gel) during a 6-month safety trial in Zimbabwe. Women were randomized to the use of a diaphragm with gel or the use of gel alone, in addition to male condoms. Ever use and use of study product on the last act of sexual intercourse were assessed monthly by Audio Computer-Assisted Self-Interviewing. Acceptability, correct use and consistent use (use at every sexual act during the previous 3 months) were measured on the last visit by face-to-face interview. Predictors of consistent use were examined using multivariate logistic regression analyses. In this sample of 117 sexually active, monogamous, contracepting women, rates of consistent use were similar in both groups (59.7% for combination method vs. 56.4% for gel alone). Product acceptability was high, but was not independently associated with consistent use. Independent predictors of consistent use included age [adjusted odds ratio (AOR)=1.08; 95% confidence interval (95% CI)=1.01-1.16], consistent condom use (AOR=3.85; 95% CI=1.54-9.63) and having a partner who approves of product use (AOR=2.66; 95% CI=1.10-6.39). Despite high reported acceptability and few problems with the products, the participants reported only moderate product adherence levels. Consistent use of condoms and consistent use of products were strongly associated. If observed in other studies, this may bias the estimation of product effectiveness in future trials of female-controlled methods.

  9. Time-Resolved Quantitative Analysis of the Diaphragms During Tidal Breathing in a Standing Position Using Dynamic Chest Radiography with a Flat Panel Detector System ("Dynamic X-Ray Phrenicography"): Initial Experience in 172 Volunteers.

    Science.gov (United States)

    Yamada, Yoshitake; Ueyama, Masako; Abe, Takehiko; Araki, Tetsuro; Abe, Takayuki; Nishino, Mizuki; Jinzaki, Masahiro; Hatabu, Hiroto; Kudoh, Shoji

    2017-04-01

    Diaphragmatic motion in a standing position during tidal breathing remains unclear. The purpose of this observational study was to evaluate diaphragmatic motion during tidal breathing in a standing position in a health screening center cohort using dynamic chest radiography in association with participants' demographic characteristics. One hundred seventy-two subjects (103 men; aged 56.3 ± 9.8 years) underwent sequential chest radiographs during tidal breathing using dynamic chest radiography with a flat panel detector system. We evaluated the excursions of and peak motion speeds of the diaphragms. Associations between the excursions and participants' demographics (gender, height, weight, body mass index [BMI], smoking history, tidal volume, vital capacity, and forced expiratory volume) were investigated. The average excursion of the left diaphragm (14.9 ± 4.6 mm, 95% CI 14.2-15.5 mm) was significantly larger than that of the right (11.0 ± 4.0 mm, 95% CI 10.4-11.6 mm) (P <0.001). The peak motion speed of the left diaphragm (inspiratory, 16.6 ± 4.2 mm/s; expiratory, 13.7 ± 4.2 mm/s) was significantly faster than that of the right (inspiratory, 12.4 ± 4.4 mm/s; expiratory, 9.4 ± 3.8 mm/s) (both P <0.001). Both simple and multiple regression models demonstrated that higher BMI and higher tidal volume were associated with increased excursions of the bilateral diaphragm (all P <0.05). The average excursions of the diaphragms are 11.0 mm (right) and 14.9 mm (left) during tidal breathing in a standing position. The diaphragmatic motion of the left is significantly larger and faster than that of the right. Higher BMI and tidal volume are associated with increased excursions of the bilateral diaphragm. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  10. SU-G-BRA-07: An Innovative Fiducial-Less Tracking Method for Radiation Treatment of Abdominal Tumors by Diaphragm Disparity Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dick, D; Zhao, W [University of Miami, Coral Gables, Florida (United States); Wu, X [Biophysics Research Institute of America, Miami, Florida (United States)

    2016-06-15

    Purpose: To investigate the feasibility of tracking abdominal tumors without the use of gold fiducial markers Methods: In this simulation study, an abdominal 4DCT dataset, acquired previously and containing 8 phases of the breathing cycle, was used as the testing data. Two sets of DRR images (45 and 135 degrees) were generated for each phase. Three anatomical points along the lung-diaphragm interface on each of the Digital Reconstructed Radiograph(DRR) images were identified by cross-correlation. The gallbladder, which simulates the tumor, was contoured for each phase of the breathing cycle and the corresponding centroid values serve as the measured center of the tumor. A linear model was created to correlate the diaphragm’s disparity of the three identified anatomical points with the center of the tumor. To verify the established linear model, we sequentially removed one phase of the data (i.e., 3 anatomical points and the corresponding tumor center) and created new linear models with the remaining 7 phases. Then we substituted the eliminated phase data (disparities of the 3 anatomical points) into the corresponding model to compare model-generated tumor center and the measured tumor center. Results: The maximum difference between the modeled and the measured centroid values across the 8 phases were 0.72, 0.29 and 0.30 pixels in the x, y and z directions respectively, which yielded a maximum mean-squared-error value of 0.75 pixels. The outcomes of the verification process, by eliminating each phase, produced mean-squared-errors ranging from 0.41 to 1.28 pixels. Conclusion: Gold fiducial markers, requiring surgical procedures to be implanted, are conventionally used in radiation therapy. The present work shows the feasibility of a fiducial-less tracking method for localizing abdominal tumors. Through developed diaphragm disparity analysis, the established linear model was verified with clinically accepted errors. The tracking method in real time under different

  11. Solid state silicon based condenser microphone for hearing aid, has transducer chip and IC chip between intermediate chip and openings on both sides of intermediate chip, to allow sound towards diaphragm

    DEFF Research Database (Denmark)

    2000-01-01

    towards diaphragm. Surface of the chip (2) has electrical conductors (14) to connect chip with IC chip (3). USE - For use in miniature electroacoustic devices such as hearing aid. ADVANTAGE - Since sound inlet is covered by filter, dust, moisture and other impurities do not obstruct interior and sound...... inlet of microphone. External electrical connection can be made economically reliable and the thermal stress is avoided with the small size solid state silicon based condenser microphone....

  12. Percutaneous radiofrequency ablation of hepatocellular carcinoma abutting the diaphragm and gastrointestinal tracts with the use of artificial ascites: safety and technical efficacy in 143 patients

    International Nuclear Information System (INIS)

    Song, Inyoung; Rhim, Hyunchul; Lim, Hyo K.; Kim, Young-sun; Choi, Dongil

    2009-01-01

    The purpose of this study was to assess the feasibility, safety and efficacy of radiofrequency ablation (RFA) with the use of artificial ascites for hepatocellular carcinoma (HCC) adjacent to the diaphragm and gastrointestinal tract. One hundred forty-three patients with 181 HCCs who underwent US-guided percutaneous RFA with the use of artificial ascites were retrospectively reviewed. Among the 181 HCCs, 148 HCCs were defined as problematic nodules for two major reasons: poor sonic window or possible thermal injury. We artificially induced ascites before performing RFA by dripping 5% dextrose in a water solution. We assessed the technical success of introducing artificial ascites, technical feasibility of the use of artificial ascites and complications. The technical success rate, as well as the primary and secondary technique success rate, was assessed by regular follow-up CT examinations. RFA with artificial ascites was successfully achieved in 130 of 143 patients. The primary technique effectiveness was 85.3%. During follow-up (mean, 20.4 months), remote intrahepatic recurrence occurred in 49 patients and local tumor progression occurred in 15 patients. Three (2.1%) of the 143 patients experienced major complications (hemoperitoneum, lobar infarction and biloma) related to the RFA procedure. The use of artificial ascites is a simple and useful technique to minimize collateral thermal injury and to improve the sonic window. (orig.)

  13. Short-term and long-term effect of diaphragm biofeedback training in gastroesophageal reflux disease: an open-label, pilot, randomized trial.

    Science.gov (United States)

    Sun, X; Shang, W; Wang, Z; Liu, X; Fang, X; Ke, M

    2016-10-01

    This study investigated the effectiveness of diaphragm biofeedback training (DBT) for patients with gastroesophageal reflux disease (GERD). A total of 40 patients with GERD treated at the Peking Union Medical College Hospital between September 2004 and July 2006 were randomized to receive DBT and rabeprazole proton pump inhibitor (PPI) or rabeprazole alone. The DBT + rabeprazole group received DBT during the 8-week initial treatment; the rabeprazole group did not. During the 6-month follow up, all patients took acid suppression according to their reflux symptoms, and the patients in the DBT + rabeprazole group were required to continue DBT. The primary outcome (used for power analysis) was the amount of acid suppression used at 6 months. Secondary outcomes were reflux symptoms, health-related quality of life (HRQL), and esophageal motility differences after the 8-week treatment compared with baseline. Acid suppression usage significantly decreased in the DBT + rabeprazole group compared with the rabeprazole group at 6 months (P reflux symptoms and GERD-HRQL were significantly improved in both groups (P gastroesophageal junction pressure (GEJP) significantly increased in the DBT + rabeprazole group (P reflux barrier, providing a non-pharmacological maintenance therapy and reducing medical costs for patients with GERD. © 2015 International Society for Diseases of the Esophagus.

  14. Association Between Carotid Bulb Diaphragm and Ischemic Stroke in Young Afro-Caribbean Patients: A Population-Based Case-Control Study.

    Science.gov (United States)

    Joux, Julien; Boulanger, Marion; Jeannin, Severine; Chausson, Nicolas; Hennequin, Jean-Luc; Molinié, Vincent; Smadja, Didier; Touzé, Emmanuel; Olindo, Stephane

    2016-10-01

    Carotid bulb diaphragm (CBD) has been described in young carotid ischemic stroke (CIS) patients, especially in blacks. However, the prevalence of CBD in CIS patients is unknown, and whether CBD is a risk factor for CIS remains unclear. We assessed the association between CBD and incident CIS in a population-based study. We selected all young (young (stroke-free patients admitted for a road crash who routinely had computed tomographic angiography. Odds ratio (ORs) were calculated by conditional logistic regression adjusted for hypertension, dyslipidemia, diabetes and smoking. CIS associated with ipsilateral CBD incidence was 3.8 per 100 000 person-years (95% confidence interval, 1.4-6.1). Prevalence of ipsilateral CBD was 23% in all CIS and 37% in undetermined CIS patients. When restricted to undetermined CIS, CBD prevalence was 24 times higher than that in controls (adjusted OR, 24.1; 95% confidence interval, 1.8-325.6). CBD is associated with an increased risk of ipsilateral CIS in young Afro-Caribbean population. © 2016 American Heart Association, Inc.

  15. Amyotrophic lateral sclerosis: the Midwestern surgical experience with the diaphragm pacing stimulation system shows that general anesthesia can be safely performed.

    Science.gov (United States)

    Onders, Raymond P; Carlin, Arthur M; Elmo, MaryJo; Sivashankaran, Subhalakashmi; Katirji, Bashar; Schilz, Robert

    2009-03-01

    There is a paucity of literature concerning general anesthesia and surgery in patients with amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease). This report summarizes the largest series of surgical cases in ALS during multicenter prospective trials of the laparoscopic diaphragm pacing system (DPS) to delay respiratory failure. The overall strategy outlined includes the use of rapidly reversible short-acting analgesic and amnestic agents with no neuromuscular relaxants. Fifty-one patients were implanted from March 2005 to March 2008 at 2 sites. Age at implantation ranged from 42 to 73 years and the percent predicted forced vital capacity (FVC) ranged from 20% to 87%. On preoperative blood gases, Pco(2) was as high as 60. Using this protocol, there were no failures to extubate or 30-day mortalities. The DPS system increases the respiratory system compliance by decreasing posterior lobe atelectasis and can stimulate respirations at the end of each case. Laparoscopic surgery with general anesthesia can be safely performed in patients with ALS undergoing DPS.

  16. Evidence towards improved estimation of respiratory muscle effort from diaphragm mechanomyographic signals with cardiac vibration interference using sample entropy with fixed tolerance values.

    Directory of Open Access Journals (Sweden)

    Leonardo Sarlabous

    Full Text Available The analysis of amplitude parameters of the diaphragm mechanomyographic (MMGdi signal is a non-invasive technique to assess respiratory muscle effort and to detect and quantify the severity of respiratory muscle weakness. The amplitude of the MMGdi signal is usually evaluated using the average rectified value or the root mean square of the signal. However, these estimations are greatly affected by the presence of cardiac vibration or mechanocardiographic (MCG noise. In this study, we present a method for improving the estimation of the respiratory muscle effort from MMGdi signals that is robust to the presence of MCG. This method is based on the calculation of the sample entropy using fixed tolerance values (fSampEn, that is, with tolerance values that are not normalized by the local standard deviation of the window analyzed. The behavior of the fSampEn parameter was tested in synthesized mechanomyographic signals, with different ratios between the amplitude of the MCG and clean mechanomyographic components. As an example of application of this technique, the use of fSampEn was explored also in recorded MMGdi signals, with different inspiratory loads. The results with both synthetic and recorded signals indicate that the entropy parameter is less affected by the MCG noise, especially at low signal-to-noise ratios. Therefore, we believe that the proposed fSampEn parameter could improve estimates of respiratory muscle effort from MMGdi signals with the presence of MCG interference.

  17. Recovery of muscle function after deep neuromuscular block by means of diaphragm ultrasonography and adductor of pollicis acceleromyography with comparison of neostigmine vs. sugammadex as reversal drugs: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Cappellini, Iacopo; Picciafuochi, Fabio; Ostento, Daniele; Danti, Ginevra; De Gaudio, Angelo Raffaele; Adembri, Chiara

    2018-02-21

    The extensive use of neuromuscular blocking agents (NMBAs) during surgical procedures still leads to potential residual paralyzing effects in the postoperative period. Indeed, neuromuscular monitoring in an intra-operative setting is strongly advocated. Acetylcholinesterase inhibitors can reverse muscle block, but their short half-life may lead to residual curarization in the ward, especially when intermediate or long-acting NMBAs have been administered. Sugammadex is the first selective reversal drug for steroidal NMBAs; it has been shown to give full and rapid recovery of muscle strength, thus minimizing the occurrence of residual curarization. Acceleromyography of the adductor pollicis is the gold standard for detecting residual curarization, but it cannot be carried out on conscious patients. Ultrasonography of diaphragm thickness may reveal residual effects of NMBAs in conscious patients. This prospective, double-blind, single-center randomized controlled study will enroll patients (of American Society of Anesthesiologists physical status I-II, aged 18-80 years) who will be scheduled to undergo deep neuromuscular block with rocuronium for ear, nose, or throat surgery. The study's primary objective will be to compare the effects of neostigmine and sugammadex on postoperative residual curarization using two different tools: diaphragm ultrasonography and acceleromyography of the adductor pollicis. Patients will be extubated when the train-of-four ratio is > 0.9. Diaphragm ultrasonography will be used to evaluate the thickening fraction, which is the difference between the end expiratory thickness and the end inspiratory thickness, normalized to the end expiratory thickness. Ultrasonography will be performed before the initiation of general anesthesia, before extubation, and 10 and 30 min after discharging patients from the operating room. The secondary objective will be to compare the incidence of postoperative complications due to residual neuromuscular

  18. Diafragmas horizontais de piso em madeira, confeccionados com chapas de OSB e vigas I, submetido ao carregamento em seu plano = Wood light-frame floor diaphragms, made with OSB panels and Ijoists, subjected to lateral loads

    Directory of Open Access Journals (Sweden)

    Altevir Castro dos Santos

    2010-10-01

    Full Text Available Este trabalho aborda nova perspectiva para construções em madeira, sob a ótica construtiva de sistemas com estruturas leves (Lightweight wood-frame construction, pela sua consagrada aplicação internacional e forte viabilidade de utilização no Brasil. Apresenta ensaios realizados pela primeira vez no Brasil, trazendo contribuição inicial sobre o assunto, com subsídios para projeto e execução de diafragmas de piso com emprego de material nacional oriundo do manejo racional de florestas cultivadas. O objetivo geral é avaliar a resistência e a rigidez de diafragmas horizontais, construídos em Sistemas Leves de Madeira, quando submetidos ao carregamento monotônico em seu plano. Para atendimento desse propósito, foram ensaiados protótipos em escala real (2,50 x 5,00 m com diferentes arranjos construtivos e avaliou-se a influência dos seguintes parâmetros: utilização de dispositivos enrijecedores entre vigas, que constituem a ossatura do diafragma horizontal; rigidez das ligações e o efeito do espaçamento entre pregos na rigidez do conjunto, composto de madeira e chapas de OSB – Oriented Strand Board Nacional. Dos ensaios realizados, concluise que o emprego de dispositivos enrijecedores permite o aumento do número de pregos de fixação no perímetro das chapas e esse acréscimo é responsável pelo aumento da resistência e rigidez dos diafragmas.This work is focused on lightweight wood-frame constructions, which are accepted worldwide and may be considered feasible for use in Brazil as well. It presents the results of experimental tests on floor diaphragms subjected to lateral loads. This is the first time this kind of test is performed in Brazil. Thus, it brings up valuable information about this subject, giving technical information that may contribute to the design and construction of floor diaphragms employing local materials that come from planted forests. The main goal of this research is to evaluate the resistance

  19. Changes in calsequestrin, TNF-α, TGF-β and MyoD levels during the progression of skeletal muscle dystrophy in mdx mice: a comparative analysis of the quadriceps, diaphragm and intrinsic laryngeal muscles.

    Science.gov (United States)

    Barros Maranhão, Juliana; de Oliveira Moreira, Drielen; Maurício, Adriana Fogagnolo; de Carvalho, Samara Camaçari; Ferretti, Renato; Pereira, Juliano Alves; Santo Neto, Humberto; Marques, Maria Julia

    2015-10-01

    In Duchenne muscular dystrophy (DMD), the search for new biomarkers to follow the evolution of the disease is of fundamental importance in the light of the evolving gene and pharmacological therapies. In addition to the lack of dystrophin, secondary events including changes in calcium levels, inflammation and fibrosis greatly contribute to DMD progression and the molecules involved in these events may represent potential biomarkers. In this study, we performed a comparative evaluation of the progression of dystrophy within muscles that are differently affected by dystrophy (diaphragm; DIA and quadriceps; QDR) or spared (intrinsic laryngeal muscles) using the mdx mice model of DMD. We assessed muscle levels of calsequestrin (calcium-related protein), tumour necrosis factor (TNF-α; pro-inflammatory cytokine), tumour growth factor (TGF-β; pro-fibrotic factor) and MyoD (muscle proliferation) vs. histopathology at early (1 and 4 months of age) and late (9 months of age) stages of dystrophy. Fibrosis was the primary feature in the DIA of mdx mice (9 months: 32% fibrosis), which was greater than in the QDR (9 months: 0.6% fibrosis). Muscle regeneration was the primary feature in the QDR (9 months: 90% of centrally nucleated fibres areas vs. 33% in the DIA). The QDR expressed higher levels of calsequestrin than the DIA. Laryngeal muscles showed normal levels of TNF-α, TGF-β and MyoD. A positive correlation between histopathology and cytokine levels was observed only in the diaphragm, suggesting that TNF-α and TGF-β serve as markers of dystrophy primarily for the diaphragm. © 2015 The Authors. International Journal of Experimental Pathology © 2015 International Journal of Experimental Pathology.

  20. Válvula fonatória brasileira para traqueotomia: padronização de pressão de diafragma Brazilian tracheotomy speech valve: diaphragm pressure standardization

    Directory of Open Access Journals (Sweden)

    Ângela Rúbia Oliveira Silveira

    2009-02-01

    Full Text Available A traqueotomia está indicada em condições com obstrução respiratória alta ou doença pulmonar obstrutiva crônica. As Válvulas Fonatórias (VF melhoram a comunicação, higienização e umidificação das vias aéreas dos pacientes traqueotomizados. OBJETIVO: Demonstrar a VF nacional, de menor custo, e sua utilização na reabilitação fonatória desses pacientes, avaliar resistência de abertura pelo diafragma, o que confere melhor conforto ao paciente. Forma de Estudo: Experimental, coorte contemporâneo. MATERIAL E MÉTODO: A VF foi utilizada em 32 pacientes. A válvula tem diafragma dentro de um corpo em aço inox com encaixes de plástico. Estudou-se grau de conforto respiratório de acordo com a resistência do diafragma da válvula, 40, 50 e 60 shores. RESULTADOS: Obteve-se uso regular da VF acoplada à cânula por todos os pacientes, 26 o fizeram por mais de 12h diárias e destes 14 por 24h diárias. A pressão do diafragma obtida foi de 40 shores para 13 pacientes e 50 shores para 19 pacientes, sem utilização de 60 shores. CONCLUSÃO: A VF metálica permite fonação, sem a oclusão digital da cânula, e respiração sob conforto. Obteve-se resistência padronizada do diafragma. Atualmente todos os pacientes do estudo utilizam estas VF com fonação e 43,75% período integral.Tracheotomy is performed in cases of upper airway obstruction or chronic pulmonary disorders. The Tracheotomy Speech Valves (TSV improve communication and airway hygiene and humidification of tracheotomized patients. AIM: To show the low cost Brazilian TSV and its use in speech rehabilitation of tracheotomized patients, to evaluate diaphragm opening resistance and comfort to the patient. Study Design: Experimental, contemporary cohort. MATERIALS AND METHODS: The TSV was used in 32 patients. The valve has a diaphragm within a stainless steel body with plastic fittings. We studied the level of respiratory comfort according to the degree of valve diaphragm

  1. Diafragmas horizontais de piso em madeira, confeccionados com chapas de OSB e vigas I, submetido ao carregamento vertical = Wood light-frame floor diaphragms, made with OSB panels and Ijoists, subjected to vertical loads

    Directory of Open Access Journals (Sweden)

    Altevir Castro dos Santos

    2007-07-01

    Full Text Available Este trabalho aborda construções em madeira sob a ótica de sistemas com estruturas leves; apresenta análise computacional por meio de modelagem pelo método de elementos finitos de diafragmas de piso e vigas I, submetidas a ensaio de flexão a quatro pontos. O objetivo geral é avaliar a resistência e a rigidez de diafragmas horizontais,construídos em Sistemas Leves de Madeira, quando submetidos a ações verticais. As análises foram realizadas por meio do programa computacional SAP2000 e foram avaliadas as influências dos seguintes parâmetros: espaçamento entre vigas que constituem os elementosde ossatura do diafragma horizontal e o espaçamento entre pregos de fixação do contrapiso, composto por chapas de OSB – Oriented Strand Board. Ao final do trabalho, comparam-se os resultados obtidos a partir das análises numérica e teórica, e são apresentadas algumasconclusões.Wood light-frame floor diaphragms, made with OSB panels and I-joists, subjected to vertical loads. This work is focused on lightweight woodframe constructions, and presents a finite element modeling of floor diaphragms and wood I-joists subjected to four-point bending. It presents the results of experimental tests on wood I-joists subjected to vertical loads. The main goal of this research is to evaluate the resistance and rigidity of wood light-frame floor diaphragms, when subjected to monotonic vertical forces acting in the plane of the floor. The analyses were performed using the SAP2000 computer program and tested with diferent constructive arrangements, and the influence of the following variables were examined: distance between wood I-joists, and distance between nails around the perimeter of the OSB boards. Finally, a comparison between analytical and numerical results is performed.

  2. Relação entre a excursão do músculo diafragma e as curvaturas da coluna vertebral em crianças respiradoras bucais The relationship between excursion of the diaphragm and curvatures of the spinal column in mouth breathing children

    Directory of Open Access Journals (Sweden)

    Liu Chiao Yi

    2008-04-01

    Full Text Available OBJETIVO: Verificar a relação entre a excursão do músculo diafragma e as curvaturas da coluna vertebral em crianças respiradoras bucais. MÉTODOS: Foram avaliadas 52 crianças de 5 a 12 anos de idade, de ambos os sexos. Por meio de avaliação otorrinolaringológica, foram divididas em dois grupos: respiradores bucais e respiradores nasais. Todos os participantes foram submetidos a exame de videofluoroscopia do músculo diafragma e a avaliação postural. A excursão do diafragma foi analisada pelo programa Adobe Photoshop®, e a avaliação postural através de fotografias em norma lateral esquerda, sendo analisadas pelo Software de Avaliação Postural. RESULTADOS: Os grupos estudados apresentaram diferença estatisticamente significante quanto ao comportamento das curvaturas da coluna vertebral (lordose cervical: p = 0,003; lordose lombar: p = 0,001; cifose torácica: p = 0,002; posição da pelve: p = 0,001 e da excursão do músculo diafragma (diafragma lado direito: p = 0,001; diafragma lado esquerdo: p = 0,001. O grupo respirador bucal apresentou diminuição da lordose cervical, aumento da cifose torácica, aumento da lordose lombar e anteversão da posição da pelve. A distância excursionada pelo músculo diafragma em crianças respiradoras bucais é menor que em crianças respiradoras nasais. Não houve significância estatística ao relacionar o comportamento das curvaturas da coluna vertebral com a excursão do músculo diafragma. CONCLUSÃO: Não há relação entre as curvaturas da coluna vertebral com a excursão do músculo diafragma nos grupos estudados.OBJECTIVE: To investigate the relationship between excursion of the diaphragm muscle and spinal curvatures in mouth breathing children. METHODS: A total of 52 children of both sexes, aged from 5 to 12 years, were studied. After otorhinolaryngological assessment, the children were divided into two groups: mouth breathers and nose breathers. All of the children underwent

  3. The number of podocyte and slit diaphragm is decreased in experimental diabetic nephropathy O número de podócitos e fendas diafragmáticas estão alterados na nefropatia diabética

    Directory of Open Access Journals (Sweden)

    Mauro Masson Lerco

    2006-04-01

    Full Text Available PURPOSE: To determine the number of podocyte, slit diaphragms, slit diaphragm extensions and GBM thickness in diabetic nephropathy. METHODS: Sixty "Rattus Wistar"of both sexes weighing 200-300g were divided in two experimental groups: normal group 10 animals, and alloxan diabetic rats - 50 animals. Alloxan was administered in a single IV dose of 42mg/kg body weight. Body weight, water and food intake, diuresis, and blood and urine glucose were determined in both groups before alloxan injection and two weeks, six and twelve months after alloxan injection. Proteinuria was measured at 12 months in both groups. After 12 months animals were sacrificed, and the right kidney processed for electron microscopy. RESULTS: Clear clinical and laboratory signs of severe diabetes were seen, in all alloxan-diabetic rats at all follow-up times. Glomerular basement membrane (GBM thickening, podocyte number, and slit diaphragm number and extension were determined. GBM of all diabetic rats was significantly thicker (median=0.29µm; semi-interquartile range=0.065µm than in the normal rats (0.23µm; 0.035µm. Diabetic rat podocyte number (8; 1, slit diaphragm number (4; 1, and slit diaphragm extension (0.021µm; 0.00435µm were significantly lower than in normal rats (11; 1 and (7; 1.5, and (0.031µm; 0.0058µm. Diabetic rat proteinuria (0.060mg/24h; 0.037mg/24h was higher than in normal rats (0.00185mg/24h; 0.00055mg/24h. CONCLUSION: Experimental diabetes is associated with significant (pOBJETIVO: Determinar o número de podocitos e fendas diafragmáticas, a extensão das fendas diafragmáticas e a espessura da Membrana Basal Glomerular (MBG na nefropatia diabética. MÉTODOS: Sessenta "Rattus Wistar" de ambos os sexos, pesando entre 200-300g, foi dividido em dois grupos experimentais: grupo normal 10 animais, e grupo diabético induzido por aloxana - 50 animais. A Aloxana foi administrada em dose única endovenosa de 42mg/kg de peso. Medimos o peso, ingestão de

  4. MÚSCULO DIAFRAGMA HOMÓLOGO CONSERVADO EM SOLUÇÃO SUPERSATURADA DE AÇÚCAR PARA REPARAÇÃO DE GRANDE DEFEITO NO DIAFRAGMA DE CÃO HOMOLOGOUS DIAPHRAGM MUSCLE CONSERVED IN SUPERSATURATED SUGAR SOLUTION TO REPAR LARGE DEFECTS IN DIAPHRAGM OF DOGS

    Directory of Open Access Journals (Sweden)

    Alexandre Mazzanti

    2001-04-01

    horizontal mattress suture, in an isolated pattern. The dogs were observed for a period of 30 days (subgroups I, 75 days (groups II and 120 days (groups III postoperatively. After this period, macroscopic observation and collection of samples for histologic evaluation were performed. It was verified in the animals of the subgroup I, partial substitution and in the subgroups II and III, total substitution of the muscular portion of the diaphragm. A fibrovascular tissue occluding the diaphragmatic defect was observed. With the postoperative evolution, a thin tissue, almost transparent, was identified. The segment of diaphragmatic muscle conserved in 300% supersaturated sugar solution, at room temperature, for repair of great defects in the diaphragmatic muscle of dogs was substituted by a fine layer of fibrous connective tissue.

  5. Effect of nitrofen in the final stages of development of the diaphragm muscle in rats Efeito do nitrofen na fase final do desenvolvimento da musculatura do diafragma em ratos

    Directory of Open Access Journals (Sweden)

    Frances Lilian Lanhellas Gonçalves

    2013-01-01

    Full Text Available PURPOSE: To evaluate the expression of myosin in muscle fibers of the diaphragm in experimental congenital diaphragmatic hernia (CDH. METHODS: Fetuses of pregnant rats were divided into four groups: External Control (EC, composed of non-manipulated rats; Nitrofen, composed of pregnant rats that received 100 mg of nitrofen (2,4-dichloro-4'nitrodiphenyl ether diluted in olive oil on gestational day (GD 9.5, whose fetuses developed CDH (N+ or not (N-, and Olive Oil Placebo (OO, composed of pregnant rats that received the oil on the same GD. The fetuses were collected on GD 18.5, 19.5, 20.5 and 21.5 (term = 22 days. We obtained body weight (BW and photographed the diaphragm area (DA, hernia area (HA and subsequent calculated the HA/DA ratio in N+ group. Samples of Diaphragm muscle were processed for histological staining with H/E and immunohistochemistry (IHQ for myosin.} RESULTS: The fetuses of N- and N+ groups had decreased BW and DA compared to EC and OO groups (p OBJETIVO: Avaliar a expressão da miosina na muscularização do diafragma na hérnia diafragmática congênita (CDH experimental. MÉTODOS: Fetos de ratas foram divididos em quatro grupos: Controle Externo (EC, composto de ratas não manipuladas; Nitrofen, composto de ratas que receberam 100 mg de nitrofen (2,4-dicloro-4'nitrodifenil éter diluído no azeite no dia de gestação (GD 9.5, cujos fetos desenvolveram CDH (N+ ou não (N- e Placebo óleo de oliva (OO, composto de ratas que ingeriram apenas óleo no mesmo GD. Os fetos foram coletados com 18,5, 19,5, 20,5 e 21,5 GD (termo = 22 dias. Foi obtido o peso corporal (BW e tiradas fotografias da área do diafragma (DA, da hérnia (HA e calculada a relação HA/DA no grupo N+. Amostras de diafragmas foram processadas histologicamente para coloração com H/E e imunohistoquímica. RESULTADOS: Os fetos dos grupos N- e N+ tiveram BW e DA diminuídos em relação aos grupos EC e OO (p<0.001. Só houve diferença na HA entre os GD 18.5 e 21

  6. Selective expression of the type 3 isoform of ryanodine receptor Ca2+ release channel (RyR3) in a subset of slow fibers in diaphragm and cephalic muscles of adult rabbits

    International Nuclear Information System (INIS)

    Conti, Antonio; Reggiani, Carlo; Sorrentino, Vincenzo

    2005-01-01

    The expression pattern of the RyR3 isoform of Ca 2+ release channels was analysed by Western blot in neonatal and adult rabbit skeletal muscles. The results obtained show that the expression of the RyR3 isoform is developmentally regulated. In fact, RyR3 expression was detected in all muscles analysed at 2 and 15 days after birth while, in adult animals, it was restricted to a subset of muscles that includes diaphragm, masseter, pterygoideus, digastricus, and tongue. Interestingly, all of these muscles share a common embryonic origin being derived from the somitomeres or from the cephalic region of the embryo. Immunofluorescence analysis of rabbit skeletal muscle cross-sections showed that RyR3 staining was detected in all fibers of neonatal muscles. In contrast, in those adult muscles expressing RyR3 only a fraction of fibers was labelled. Staining of these muscles with antibodies against fast and slow myosins revealed a close correlation between expression of RyR3 and fibers expressing slow myosin isoform

  7. The effect of magnesium sulfate concentration on the effective concentration of rocuronium, and sugammadex-mediated reversal, in isolated left phrenic nerve hemi-diaphragm preparations from the rat.

    Science.gov (United States)

    Cho, Choon-Kyu; Sung, Tae-Yun; Choi, Seok-Jun; Choi, Hey-Ran; Kim, Yong Beom; Lee, Jung-Un; Yang, Hong-Seuk

    2018-05-30

    Perioperative magnesium sulfate (MgSO4) is used for analgesic, anti-arrhythmic, and obstetric purposes. The effects of MgSO4 on the neuromuscular blockade (NMB) induced by rocuronium, and the sugammadex reversal thereof, have not been clearly quantified. We investigated the effect increase concentrations of MgSO4 on the NMB by rocuronium, and sugammadex reversal, in isolated left phrenic nerve hemi-diaphragm (PNHD) preparations from the rat. Rat PNHD preparations were randomly allocated to one of four groups varying in terms of MgSO4 concentration (1, 2, 3, and 4 mM, each n = 10, in Krebs solution). The train-of-four (TOF) and twitch height responses were recorded mechanomyographically. The preparations were treated with incrementally increasing doses of rocuronium and each group's effective concentration (EC)50, EC90, and EC95 of rocuronium were calculated via nonlinear regression. Then, sugammadex was administered in doses equimolar to rocuronium. The recovery index, time to T1 height >95% of control, and the time to a TOF ratio (TOFR) >0.9 after sugammadex administration were measured. The EC50, EC90, and EC95 of rocuronium fell significantly as the magnesium level increased. The EC50, EC90, and EC95 of rocuronium did not differ between the 3 and 4 mM groups. The recovery index, time to T1 height >95% of control, and time to a TOFR >0.9 after sugammadex administration did not differ among the four groups. Increases in the magnesium concentration in rat PNHD preparations proportionally enhanced the NMB induced by rocuronium but did not affect reversal by equimolar amounts of sugammadex.

  8. Birth Control: How to Use Your Diaphragm

    Science.gov (United States)

    ... Emotional Well-Being Mental Health Sex and Birth Control Sex and Sexuality Birth Control Family Health Infants and Toddlers Kids and Teens ... MoreBMI Calculator Vasectomy: What to ExpectProgestin-Only Birth Control PillsDepo-Provera: An Injectable ContraceptiveTubal Sterilization (Tubal Ligation) ...

  9. Diaphragms in air-operated valves

    Energy Technology Data Exchange (ETDEWEB)

    Groeger, J.E.

    1996-12-01

    The author will present current issues related to diaphgrams in air-operated valves. Altran Materials Engineering, Inc., often performs root-cause analyses for nuclear power plant owners. The author will discuss various analyses that have been performed or are currently underway.

  10. Detection of Anomalies in Diaphragm Walls

    NARCIS (Netherlands)

    Spruit, R.; Van Tol, F.; Broere, W.

    2015-01-01

    If a calamity with a retaining wall occurs, the impact on surrounding buildings and infrastructure is at least an order of magnitude more severe than without the calamity. In 2005 and 2006 major leaks in the retaining walls of underground stations in Amsterdam and Rotterdam occurred. After these

  11. Ventilação elétrica: indicações e aspectos técnicos do implante cirúrgico do marca-passo de estimulação diafragmática Electric ventilation: indications for and technical aspects of diaphragm pacing stimulation surgical implantation

    Directory of Open Access Journals (Sweden)

    Miguel Lia Tedde

    2012-10-01

    Full Text Available OBJETIVO: Pacientes com lesão medular cervical alta em geral são dependentes de ventilação mecânica, que, embora salve vidas, está associada a complicações e redução da expectativa de vida devido a infecções respiratórias. A estimulação do diafragma por marca-passo, às vezes chamada de ventilação elétrica, induz a inspiração por estimulação dos músculos inspiratórios. Nosso objetivo foi destacar as indicações e alguns aspectos da técnica cirúrgica empregada no implante laparoscópico dos eletrodos, assim como descrever cinco casos de pacientes tetraplégicos submetidos à técnica. MÉTODOS: A seleção dos pacientes envolveu estudos de condução do nervo frênico por via transcutânea para determinar se os nervos estavam preservados. A abordagem cirúrgica foi laparoscopia clássica, com quatro trocartes. A técnica foi iniciada com o mapeamento elétrico para encontrar os "pontos motores" (pontos de contração máxima do diafragma. Se o mapeamento era bem-sucedido, dois eletrodos eram implantados na face abdominal de cada lado do diafragma para estimular ramos do nervo frênico. RESULTADOS: Dos cinco pacientes, três e um, respectivamente, eram capazes de respirar somente com o uso do marca-passo por períodos superiores a 24 e 6 h, enquanto um não era capaz. CONCLUSÕES: Embora seja necessário um acompanhamento mais longo para chegar a conclusões definitivas, os resultados iniciais são promissores, pois, no momento, a maioria dos nossos pacientes pode permanecer sem ventilação mecânica por longos períodos de tempo.OBJECTIVE: Patients with high cervical spinal cord injury are usually dependent on mechanical ventilation support, which, albeit life saving, is associated with complications and decreased life expectancy because of respiratory infections. Diaphragm pacing stimulation (DPS, sometimes referred to as electric ventilation, induces inhalation by stimulating the inspiratory muscles. Our objective

  12. Reparação do diafragma de cães com segmento muscular homólogo ortotópico conservado em solução supersaturada de açúcar Diaphragm repair in dogs with muscular homologous ortothopic segment preserved in supersaturated sugar solution

    Directory of Open Access Journals (Sweden)

    A. Mazzanti

    2001-02-01

    Full Text Available O uso de enxerto muscular homólogo conservado em solução supersaturada de açúcar a 300% foi pesquisado no músculo diafragma de cães. Foram utilizados 12 cães adultos, quatro machos e oito fêmeas, sem raça definida, com peso entre 9 e 18kg, para confecção de um defeito diafragmático na porção muscular, com dimensões de 4,0 × 4,5cm, seguido da implantação de um segmento de músculo diafragma homólogo. Seis cães foram observados por um período de 30 dias de pós-operatório e seis por 60 dias, quando foram reoperados para observação macroscópica e coleta de amostra para avaliação histológica. Nos animais do grupo de 30 dias de pós-operatório verificou-se substituição parcial e nos de 60 dias, substituição total da porção muscular do diafragma por tecido de granulação, o que permitiu o restabelecimento completo do diafragma por meio de firme inserção. O segmento de músculo diafragma homólogo conservado em solução supersaturada de açúcar a 300%, em temperatura ambiente, pode ser utilizado para reparação de defeitos diafragmáticos, uma vez que é substituído por tecido conjuntivo fibroso, sem apresentar sinais clínicos nem histológico de rejeição.The viability of tissular healing of a muscular homologous ortothopic diaphragmatic segment preserved in hipersaturated sugar solution at 300% was studied as an implant in the canine diaphragmatic muscle. Twelve adult mongrel dogs were used, four males, and eight females weighing 9 to 18kg. A diaphragmatic defect, measuring 4.0 × 4.5 cm, was provoked in the muscular portion of the diaphragm for the implantation of the homologous diaphragmatic muscle segment. Six animals were observed for 30 days after the surgery and the other six for 60 days. After this period, they were reoperated, for macroscopic observation and collection of samples for histologic evaluation. A partial replacement of the implant was observed in the 30-day observation group whereas in

  13. Diaphragm size and sensitivity for fiber optic pressure sensors

    Science.gov (United States)

    He, Gang; Cuomo, Frank W.; Zuckerwar, Allan J.

    1991-01-01

    A mechanism which leads to a significant increase in sensitivity and linear operating range in reflective type fiber optic pressure transducers with minute active dimensions is studied. A general theoretical formalism is presented which is in good agreement with the experimental data. These results are found useful in the development of small pressure sensors used in turbulent boundary layer studies and other applications.

  14. Potential for Revitalisation of the Diaphragm for Family Planning in ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    Barrier contraceptives are not new to Uganda. ... procurement, and delivery mechanisms for family ... *Provider category includes staff from government and nongovernmental organisation ..... terms of the HealthTech Cooperative Agreement.

  15. Les traumatismes du diaphragme en urgence clinique et ...

    African Journals Online (AJOL)

    The male predominance was clean with a sex ratio of 5. The middle age ... The exam clinic and the x-ray standard of the thorax permit the diagnosis. ... La coupole droite était lésée dans 45,2% des cas et dans 54,8% la lésion était à gauche.

  16. Laparoscopic repair of penetrating injury of the diaphragm: an ...

    African Journals Online (AJOL)

    In this study we review our experience in using laparoscopy as a diagnostic and therapeutic tool in dealing with penetrating diaphragmatic injuries due to stab wounds and look at the feasibility of using this procedure in other similar institutions. Thirty patients, all of whom were males 20-30 years of age, presented to the ...

  17. [Diaphragm dysfunction in patients with chronic obstructive pulmonary disease

    NARCIS (Netherlands)

    Verheul, A.J.; Dekhuijzen, P.N.R.

    2003-01-01

    Chronic obstructive pulmonary disease (COPD) is characterised by alterations in the airways and lung parenchyma resulting in an increased respiratory workload. Besides an increased load and hyperinflation of the thorax, additional factors, such as systemic inflammation, oxidative stress, hypoxia and

  18. Influência do lítio no bloqueio neuromuscular produzido pelo atracúrio e pelo cisatracúrio: estudo em preparações nervo frênico-diafragma de rato Influencia del litio en el bloqueo neuromuscular producido por el atracurio y por el cisatracurio: estudio en preparo nervio frénico-diafragma del ratón Influence of lithium on the neuromuscular blockade produced by atracurium and cisatracurium: study on rat phrenic nerve-diaphragm preparations

    Directory of Open Access Journals (Sweden)

    Samanta Cristina Antoniassi Fernandes

    2007-06-01

    alteraciones en los potenciales de placa terminal en miniatura mostraron una acción presináptica.BACKGROUND AND OBJECTIVES: Lithium is widely used for the treatment of bipolar disorders and can interact with neuromuscular blockers. There is a controversy about the mechanisms by which it affects neuromuscular transmission and its interaction with neuromuscular blockers. The objective of this study was to evaluate, on the rat diaphragm, the effects of lithium on the muscular response and indirect stimulation, and the possible interaction with neuromuscular blockers. METHODS: Rats weighing between 250 and 300 g were sacrificed under urethane anesthesia. The phrenic nerve-diaphragm preparation was assembled according to the Bulbring technique. The diaphragm was kept under tension, connected to an isometric transducer, and submitted to indirect stimulation with a frequency of 0.1 Hz. The contractions of the diaphragm were registered on a physiograph. The analysis of the amplitude of the muscular responses evaluated: the effects of the isolated drugs: lithium (1.5 mg.mL-1; atracurium (20 µg.mL-1, and cisatracurium (3 µg.mL-1; the lithium-neuromuscular blockers association; and the effects of lithium on the neuromuscular blockade produced by atracurium (35 µg.mL-1 and cisatracurium (5 µg.mL-1. The effects were evaluated before and 45 minutes after the addition of the drugs. The effects of lithium on membrane potentials (MP and miniature end-plate potentials (MEPP were also evaluated. RESULTS: Lithium by itself did not change the amplitude of the muscular responses, but it decreased significantly the neuromuscular blockade produced by atracurium and cisatracurium. It did not change MP and caused an initial increase in MEPP. CONCLUSIONS: Lithium by itself did not compromise neuromuscular transmission and increased the resistance to the effects of atracurium and cisatracurium. It did not show any action on the muscle fiber, and the changes in miniature end-plate potentials

  19. 'Continuation rate', 'use-effectiveness' and their assessment for the diaphragm and jelly method.

    Science.gov (United States)

    Chandrasekaran, C; Karkal, M

    1972-11-01

    Abstract The application of the life-table technique in the calculation of use-effectiveness of a contraceptive was proposed by Potter in 1963.(1) The technique was also found to be useful in assessing the duration for which the use of a contraceptive was continued. The keen interest that existed in the use of IUD in the mid-1960's was reflected in the terminology developed for assessment of the continuity of use. 'Retention rate' was a frequently used index.(2) Because of the development of the concept of segments whose end-period determined either termination of the use of a method or its continuance on a cut-off date, 'closure rate' and 'termination rate' have been used as measures of the discontinuance of the use of methods primarily of the IUD.(3) While discussing concepts relating to acceptance, use and effectiveness of family planning methods, more generally, an expert group suggested that 'continuation' should be used to denote that a client (or a couple) had begun to practise a method and that the method was still being practised.(4) Since this group defined 'an acceptor' as a person taking service and/or advice, i.e. having an IUD insertion or a sterilization operation or receiving supplies (or advice on methods such as 'rhythm' or coitus-interruptus with the intent of using the method), the base for the assessment of continuation rates, according to this group, would be only those acceptors who had begun using the method. The lifetable method has also been used for the study of the continuation rate for pill acceptors.(5) Balakrishnan, et al., made a study of continuation rates of oral contraceptives using the multiple decrement life-table technique.(6).

  20. Intermittent spatial separation of diaphragm and lower esophageal sphincter favors acidic and weakly acidic reflux

    NARCIS (Netherlands)

    Bredenoord, Albert J.; Weusten, Bas L. A. M.; Timmer, Robin; Smout, André J. P. M.

    2006-01-01

    BACKGROUND & AIMS: In small hiatal hernias, the size of the hernia is variable. Intermittent complete reduction can be observed with high-resolution manometry as a transition from a double-peak (hernia) to a single-peak (reduced) high-pressure zone. The aim of this study was to investigate whether

  1. Compression resistance and shear strength of Guadua angustiolia culms after drilling of the node diaphragm

    Directory of Open Access Journals (Sweden)

    Juan Carlos Camargo García

    2014-06-01

    Full Text Available La preservación de culmos de guadua (Guadua angustifolia es un proceso fundamental que contribuye a garantizar  la calidad de estos cuando luego de ser cosechados son usados en distintas aplicaciones como muebles, artesanías y especialmente estructuras. El uso de boro y ácido bórico, es una de las prácticas más comunes para preparar soluciones preservantes. Para facilitar la absorción de la solución persevante durante la inmersión, el diafragma de los culmos es perforado. En este estudio, mediante un experimento factorial, se evaluó el posible efecto que puede tener la perforación del diafragma en la resistencia al corte y a la compresión de los culmos. Adicionalmente, su madurez fue incluida como otro factor, considerando dos formas de definirla: el método tradicional, a partir de características externas, y otro, mediante la selección de culmos marcados previamente (hace 4 años al momento de haber emergido del suelo. Los análisis de varianza no mostraron ningún efecto o cambio significativo (P > 0.05 en las propiedades mecánicas evaluadas, cuando se evaluaron culmos perforados y no perforados. No obstante, aquellos cuya madurez fue definida mediante el método tradicional mostraron en promedio menor resistencia al corte y a la compresión que los previamente marcados. De otro lado, la humedad de las probetas mostró un efecto significativo (p < 0.05 cuando fue incluida en el modelo de análisis de varianza como covariable y valores más altos de esta variable se asociaron a mayor resistencia de los culmos.

  2. Seismic Response of a Half-Scale Masonry Building with Flexible Diaphragms

    National Research Council Canada - National Science Library

    Sweeney, Steven C; Horney, Matthew A; Orton, Sarah L

    2005-01-01

    Unreinforced masonry (URM) buildings constructed on Army installations before the development of modern seismic codes may be susceptible to earthquake damage and therefore could benefit from seismic mitigation measures...

  3. Agenesis of dorsal pancreas with eventration of diaphragm and intrapancreatic pseudocyst: a rare entity

    Directory of Open Access Journals (Sweden)

    Poras Chaudhary

    2013-02-01

    Full Text Available A case of acute pancreatitis in a 43-year-old male patient, which was eventually diagnosed as agenesis of dorsal pancreas with eventration of left hemidiaphragm and intrapancreatic pseudocyst is being reported.

  4. Diaphragm muscle fiber dysfunction in chronic obstructive pulmonary disease: toward a pathophysiological concept.

    NARCIS (Netherlands)

    Ottenheijm, C.A.C.; Heunks, L.M.A.; Dekhuijzen, P.N.R.

    2007-01-01

    Inspiratory muscle weakness in patients with chronic obstructive pulmonary disease (COPD) is of major clinical relevance; maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to

  5. Roentgenological assessment of diaphragm functional state in case of degenerative dystrophic injuries of the skeleton

    International Nuclear Information System (INIS)

    Dmitriev, A.E.; Arapov, N.A.

    1989-01-01

    The results of complex clinicoroengenological investigations of patients with degenerative dystrophic injuries of the backbone are presented. It is shown that the conditions of functioning of the inspiratory muscle group greatly change in the case of this pathology. The most typical picture is observed during the disease exacerbation when costovertebral and costotrasverse joints were drawn into the process. The greater increase of the motion amplitude corresponding to a half of the diagram was revealed in the presence of a considerably more pronounced osteoarthosis phenomena from any side. The necessity is shown to take into account in the case of osteochondrosis of the cervical and thoracal spinal sections the reconstruction of respiration mechanisms takes place

  6. Determination of uranyl nitrate diffusion coefficients in organic and aqueous media using the porous diaphragm method

    International Nuclear Information System (INIS)

    Chierice, G.O.

    1974-01-01

    The diffusion coefficient is one of the parameters necessary for the obtention of the extraction exponential coefficients, that are contained within the H.T.U. (height of transfer unity) calculation expression, when operating with continuous organic phase. The organic phase used was tri-n-butyl-phosphate (TBP) and varsol in the 35% and 65% proportions respectively. After each experiment, the uranium content present in each compartment was spectrophotometrically determined and the quantities contained in the aqueous phases were determined by means of volumetric titration. It was found out that the uranyl ion diffusion coefficient is two and one half times less in organic phase, this just being attributed to the greater interactions of the uranyl ions in organic than in aqueous medium

  7. Androgen receptors in the pelvic diaphragm muscles of dogs with and without perineal hernia.

    Science.gov (United States)

    Mann, F A; Nonneman, D J; Pope, E R; Boothe, H W; Welshons, W V; Ganjam, V K

    1995-01-01

    Levator ani and coccygeus muscle estrogen and androgen receptors were measured in 6, healthy, > or = 5-year-old, noncastrated, male Beagles (controls) and in 24 dogs with perineal hernia. Estrogen and androgen receptor analyses were performed on levator ani and coccygeus muscle specimens obtained from control dogs at the time of castration; contralateral levator ani and coccygeus muscle specimens were assayed 2 months after castration. During herniorrhaphy of dogs with perineal hernia, levator ani (non-castrated, n = 12; castrated, n = 7) and/or coccygeus (noncastrated, n = 5; castrated, n = 4) muscle biopsy specimens were obtained for estrogen and androgen receptor analyses. For estrogen and androgen receptor assays, each muscle biopsy specimen was homogenized in Tris-EDTA-glycerol buffer, and centrifuged at 30,000 x g; extracts were used for binding with ligands: [3H]methyltrienolone (3HR1881) for androgen receptors, and [3H]estradiol-17 beta for estrogen receptors. Extracts were incubated overnight at 0 to 4 C. Nonspecific binding was estimated, using 100-fold concentration of cold ligands. Bound and free hormones were separated, using hydroxylapatite batch assay. Receptor numbers for each tissue were calculated as femtomoles (fmol) per milligram of protein. Quantified data were compared between precastration and postcastration controls, using a paired t-test. One-way ANOVA and Bonferroni post-hoc test were used to compare values for precastration controls, postcastration controls, castrated dogs with perineal hernia, and noncastrated dogs with perineal hernia. Significance was set at P < 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Laparoscopy or clinical follow-up to detect occult diaphragm injuries ...

    African Journals Online (AJOL)

    -sided thoracoabdominal stab wounds: A pilot randomized controlled trial. ... Abstract. Background: The purpose of this study was to determine whether patients with left-sided thoracoabdominal (TA) stab wounds can be safely treated with ...

  9. Seismic Response of Low-Rise Masonry Buildings With Flexible Roof Diaphragms

    National Research Council Canada - National Science Library

    Cohen, Gregory

    2001-01-01

    This study compares the responses from shaking-table testing and analytical predictions evaluated in the context of geometric scaling, to provide a coherent description of the seismic response of low...

  10. Ramification and distribution of the phrenic nerves in diaphragm of horses

    Directory of Open Access Journals (Sweden)

    Wilson Santiago

    1990-12-01

    Full Text Available The phrenic nerve distribution in 50 diaphragmas from mixed breeding adult horses (25 males and 25 females obtained from a slaughter house ("Avante", located in Araguari, State of Minas Gerais, was studied. The results indicated the following characteristics: 1 the ventral branch and laterodorsal trunk were extended 42 times (84% to the right side, 5 times (10% to the left, while the dorsal and the lateroventral trunk were 40 times (80% to the left and 2 times (4% to the right. The common origin of the dorsal, lateral and ventral branch were 6 times (12% to the right and 5 times (10% to the left. 2 The right and left bifurcation of the phrenic nerve were symmetrically arranged in: laterodorsal trunk and ventral branch 9 times (18%; lateroventral trunk and dorsal branch 5 times (10% and simultaneously in lateral and ventral dorsal branches 2 times (4%. 3 The right and left dorsal branches of the phrenic nerve were always distributed on the limbar portion (medial and lateral pillar in relation to their origins. The distribution of the nervous fillets from the right dorsal branch to the dorsal foliolo was: one fillet 10 times (20% and 2 fillets 1 time (2% respectively. To the tendinous center one fillet (2% was observed. From the left dorsal branch in 50 times (100% there was one fillet going to the right medial pillar. In relation to the left dorsal foliolo there was: one fillet 3 times (6% and 2 fillets 3 times (6% and in relation to the tendinous center there was: one fillet 3 times (6%; 2 fillets 2 times (4% and 4 fillets just once (2%. 4 From the right and left lateral branches of the phrenic nerve in all observations (100% there were fillets going to the lateral dorsal region in both sides. The distribution of the emerging fibers from the right lateral branch to the do sal foliolo was 1  fillet 6 times (12%; 2 fillets 3 times (6%; 3 fillets 1 time (2% and to the right lateral pillar 1 fillet 2 times (4%. The distribution of the emerging fibers from the left lateral branch to the dorsal foliolo was 1 fillet 8 times (16% and 2 fillets 2 times (4%. 5 The right and left ventral branches of the phrenic nerve were distributed to the lateroventral and external region in all observations (100%. It was also observed that from the right ventral branch to the tendinous center, there was one fillet in three observations (6%; to the caudal portion of the vena cava there was one fillet in two observations (4% and to the right ventral foliolo there  as one fillet in just one observation (2X . The homolateral anastomosis, between the dorsal and lateral branches, was seen in 10 observations  (20%. The distribution of these anastomosis between the dorsal and lateral branch was: to the right side in 6 observations (12%; to the left side in 2 observations (4% and in the both sides in 2 observations (4%. The heterolateral anastomosis between the right and left dorsal branch was registered just in one observation (2%. 7 There was no significant difference (p < 0,05 in the distribution of diaphragma nerves between males and females.

  11. Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges : technical summary report.

    Science.gov (United States)

    2004-03-01

    Most highway bridges are built as cast-in-place : reinforced concrete slabs and prestressed concrete : girders. The shear connectors on the top of the girders : assure composite action between the slabs and : girders. The design guidelines for bridge...

  12. Radiology of the diaphragm, pleura, thoracic cage, and upper air passages (excluding the larynx)

    International Nuclear Information System (INIS)

    Meschan, I.

    1987-01-01

    1. Abnormalities in function. 2. Abnormalities in position. 3. Abnormalities in shape (configuration). 4. Abnormalities in size or integrity. 5. Abnormalities in density and architecture (both internal and external). 6. Abnormalities in number. 7. Changes in respect to time. 8. Changes as a result of treatment, surgery, or medication. They are described in this chapter

  13. Ultrasonography evaluation during the weaning process: the heart, the diaphragm, the pleura and the lung.

    Science.gov (United States)

    Mayo, P; Volpicelli, G; Lerolle, N; Schreiber, A; Doelken, P; Vieillard-Baron, A

    2016-07-01

    On a regular basis, the intensivist encounters the patient who is difficult to wean from mechanical ventilatory support. The causes for failure to wean from mechanical ventilatory support are often multifactorial and involve a complex interplay between cardiac and pulmonary dysfunction. A potential application of point of care ultrasonography relates to its utility in the process of weaning the patient from mechanical ventilatory support. This article reviews some applications of ultrasonography that may be relevant to the process of weaning from mechanical ventilatory support. The authors have divided these applications of ultrasonography into four separate categories: the assessment of cardiac, diaphragmatic, and lung function; and the identification of pleural effusion; which can all be evaluated with ultrasonography during a dynamic process in which the intensivist is uniquely positioned to use ultrasonography at the point of care. Ultrasonography may have useful application during the weaning process from mechanical ventilatory support.

  14. Reliability of an analysis method for measuring diaphragm excursion by means of direct visualization with videofluoroscopy.

    Science.gov (United States)

    Yi, Liu C; Nascimento, Oliver A; Jardim, José R

    2011-06-01

    The purpose of this study was to verify the reproducibility between two different observers of an analysis method for diaphragmatic displacement measurements using direct visualization with videofluoroscopy. 29 mouth breathing children aged 5 to 12 years from both genders were analyzed. The diaphragmatic displacement evaluation was divided in three parts: videofluoroscopy with VHS recording in standing, sitting, and dorsal positions; digitalization of the images; and measurement of the distance between diaphragmatic domes during a breathing cycle using Adobe Photoshop 5.5 and Adobe Premiere PRO 6.5 software. The intraclass correlation coefficients presented excellent reproducibility in all positions, with coefficients always above 0.94. Mean of the measurements of the diaphagramatic domes displacement done by the two observers were similar (Phealthcare professionals. Copyright © 2010 SEPAR. Published by Elsevier Espana. All rights reserved.

  15. Probing of the peripheral plasma of a tokamak by diaphragm thermography

    International Nuclear Information System (INIS)

    Gyunter, K.; Grunov, K.; Evstigneev, S.A.

    1985-01-01

    The tokamak limiter diverts significant particle and energy fluxes from the plasma and sharply decreases the interaction between the plasma and wall, thus protecting the wall from destruction and the plasma from catastrophic contamination. The temperature of a moveble limiter is measured in the device on the basis of the infrared radiation from its surface. By applying certain models of the layer near the wall this permits to calculate the magnitude of the heat flux directed to the limiter. The power density is, in normal discharges, 2-3 kW/cm 2 ; in discharges with disruptions the power density may reach 10 kW/cm 2 . The measurements show that longitudinal energy flux in the peripheral layer of the plasma filament decreases radially in an exponential manner and can yield the parameter of the decrease. It is found that during discharges involving breakdown a very nonuniform heating of the limiter surface occurs at the initial and final stages of normal discharges, this indicates the existence of a certain structure of the peripheral plasma layer

  16. Probabilistic analysis of soil : Diaphragm wall friction used for value engineering of deep excavation, north/south metro Amsterdam

    NARCIS (Netherlands)

    Buykx, S.M.; Delfgaauw, S.; Bosch, J.W.

    2009-01-01

    The excavation of deep building pits often requires a check against failure by uplift of low permeability ground layers below excavation level. Whenever the weight of these soil layers is less than the pore-water pressure underneath, measures to resist buoyancy are to be considered. The measures

  17. Stereotactic radiotherapy by cyberknife of sub-diaphragm digestive tumors; Radiotherapie stereotaxique par Cyberknife des tumeurs digestives sous diaphragmatiques

    Energy Technology Data Exchange (ETDEWEB)

    Taste, H.; Peiffert, D.; Beckendorf, V.; Marchesi, V.; Noel, A. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France)

    2009-10-15

    The stereotactic radiotherapy is a low toxic, efficient therapy offering a supplementary curative alternative, with promising first results, confirmed by literature. ts indications, its place in the therapy strategy stay to determine in the clinical research program. (N.C.)

  18. Pseudodynamic tests on a full-scale 3-storey precast concrete building: Behavior of the mechanical connections and floor diaphragms

    OpenAIRE

    Bournas, Dionysios A.; Negro, Paolo; Molina, Francisco J.

    2013-01-01

    A full-scale three-storey precast building was tested under seismic conditions at the European Laboratory for Structural Assessment in the framework of the SAFECAST project. The unique research opportunity of testing a complete structural system was exploited to the maximum extent by subjecting the structure to a series of pseudodynamic (PsD) tests and by using four different structural layouts of the same mock-up, while 160 sensors were used to monitor the global and local response of each l...

  19. Left is right and right is wrong: fluorodeoxyglucose uptake in left hemi-diaphragm due to right phrenic nerve palsy

    International Nuclear Information System (INIS)

    Joshi, Prathamesh; Lele, Vikram

    2013-01-01

    A 36-year-old Indian man, a recently diagnosed case of the right lung carcinoma underwent fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) for staging of the malignancy. PET/CT showed increased FDG uptake in the right lung mass, consistent with the known primary tumor. Right hemidiaphragm was found to be elevated on CT, suggesting right diaphragmatic paresis. The PET scan demonstrated asymmetric, intense FDG uptake in the left hemidiaphragm and accessory muscles of respiration, which was possibly due to compensatory increased workload related to contralateral right diaphragmatic paresis. The right diaphragmatic paresis was hypothesized to be caused by phrenic nerve palsy by right lung neoplasm. (author)

  20. Immunocytochemical demonstration of M1 muscarinic acetylcholine receptors at the presynaptic and postsynaptic membranes of rat diaphragm endplates

    Czech Academy of Sciences Publication Activity Database

    Malomouzh, A. I.; Arkhipova, S. S.; Nikolsky, E. E.; Vyskočil, František

    2011-01-01

    Roč. 60, č. 1 (2011), s. 185-188 ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA500110905; GA ČR GA202/09/0806 Institutional research plan: CEZ:AV0Z50110509 Keywords : skeletal muscle * M1 muscarinic receptor Subject RIV: ED - Physiology Impact factor: 1.555, year: 2011

  1. Left is right and right is wrong: Fluorodeoxyglucose uptake in left hemi-diaphragm due to right phrenic nerve palsy.

    Science.gov (United States)

    Joshi, Prathamesh; Lele, Vikram

    2013-01-01

    A 36-year-old Indian man, a recently diagnosed case of the right lung carcinoma underwent fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) for staging of the malignancy. PET/CT showed increased FDG uptake in the right lung mass, consistent with the known primary tumor. Right hemidiaphragm was found to be elevated on CT, suggesting right diaphragmatic paresis. The PET scan demonstrated asymmetric, intense FDG uptake in the left hemidiaphragm and accessory muscles of respiration, which was possibly due to compensatory increased workload related to contralateral right diaphragmatic paresis. The right diaphragmatic paresis was hypothesized to be caused by phrenic nerve palsy by right lung neoplasm.

  2. Diaphragm myoclonus followed by generalised atonia in a patient with trisomy 4p: unusual semiology in an unusual condition.

    Science.gov (United States)

    Varley, James; Wehner, Tim; Sisodiya, Sanjay

    2015-12-01

    In this report, we describe a female patient with trisomy 4p, a rare genetic condition, with unusual seizure semiology. The patient is one of the oldest reported survivors with this condition. This semiology was noted while she was being monitored by inpatient video telemetry. We observed a series of myoclonic shoulder jerks, followed by hiccup-like episodes, and finally an atonic head drop. Corresponding ictal EEG showed semi-rhythmic high-amplitude slow waves with spikes superimposed over the frontotemporal areas. This semiology was confirmed as habitual by her parents. Subsequent hiccup-like episodes had no EEG correlate, and the head drop was again associated with semi-rhythmic high-amplitude slow waves and superimposed spikes, more prominent over the right hemisphere. In addition, we review the several cases in which hiccups have been associated with seizures and how this may relate to the neural pathways involved in the pathophysiology of hiccups. We believe the ictal hiccup-like episodes followed by atonia to be a seizure semiology that has not previously been documented. [Published with video sequence].

  3. Room-Temperature Pressure-Induced Optically-Actuated Fabry-Perot Nanomechanical Resonator with Multilayer Graphene Diaphragm in Air

    Directory of Open Access Journals (Sweden)

    Cheng Li

    2017-11-01

    Full Text Available We demonstrated a miniature and in situ ~13-layer graphene nanomechanical resonator by utilizing a simple optical fiber Fabry-Perot (F-P interferometric excitation and detection scheme. The graphene film was transferred onto the endface of a ferrule with a 125-μm inner diameter. In contrast to the pre-tension induced in membrane that increased quality (Q factor to ~18.5 from ~3.23 at room temperature and normal pressure, the limited effects of air damping on resonance behaviors at 10−2 and 105 Pa were demonstrated by characterizing graphene F-P resonators with open and micro-air-gap cavities. Then in terms of optomechanical behaviors of the resonator with an air micro-cavity configuration using a polished ferrule substrate, measured resonance frequencies were increased to the range of 509–542 kHz from several kHz with a maximum Q factor of 16.6 despite the lower Knudsen number ranging from 0.0002 to 0.0006 in damping air over a relative pressure range of 0–199 kPa. However, there was the little dependence of Q on resonance frequency. Note that compared with the inferior F-P cavity length response to applied pressures due to interfacial air leakage, the developed F-P resonator exhibited a consistent fitted pressure sensitivity of 1.18 × 105 kHz3/kPa with a good linearity error of 5.16% in the tested range. These measurements shed light on the pre-stress-dominated pressure-sensitive mechanisms behind air damping in in situ F-P resonant sensors using graphene or other 2D nanomaterials.

  4. Conditions of vacuum physics for selection of the material of first wall and diaphragm of the demonstration thermonuclear reactor-tokamak (T-20)

    International Nuclear Information System (INIS)

    Gusev, V.M.; Guseva, M.I.; Gervids, V.I.; Kogan, V.I.; Martynenko, Yu.V.; Mirnov, S.V.

    A model is given for plasma interaction with the wall and the introduction of contaminants. The model was characterized by two kinds of uncertainty. First, the uncertain behavior of the contaminants, and second, the uncertainty of boundary conditions. Some of the conclusions from the study are described

  5. Different sensitivity of miniature endplate currents of the rat extensor digitorum longus, soleus and diaphragm muscles to a novel acetylcholinesterase inhibitor C-547

    Czech Academy of Sciences Publication Activity Database

    Petrov, K. A.; Kovyazina, I. V.; Zobov, V. V.; Bukharaeva, E. A.; Nikolsky, E. E.; Vyskočil, František

    2006-01-01

    Roč. 55, č. 5 (2006), s. 585-589 ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA5011411; GA MŠk(CZ) LC554; GA ČR(CZ) GA305/02/1333 Institutional research plan: CEZ:AV0Z50110509 Keywords : acetylcholine * anticholinesterase Subject RIV: ED - Physiology Impact factor: 2.093, year: 2006

  6. Different sensitivity of miniature endplate currents in rat external and internal intercostal muscles to the acetylcholinesterase inhibitor C-547 as compared with diaphragm and extensor digitorum Pontus

    Czech Academy of Sciences Publication Activity Database

    Petrov, K.; Kovyazina, I.; Zobov, V.; Bukharaeva, E.; Nikolsky, E. E.; Vyskočil, František

    2009-01-01

    Roč. 58, č. 1 (2009), s. 149-153 ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA5011411; GA AV ČR(CZ) IAA100110501; GA MŠk(CZ) LC554 Grant - others:Russian Foundation for Basic Research(RU) 07-04-01137; Russian Foundation for Basic Research(RU) 07-04-12097 Institutional research plan: CEZ:AV0Z50110509 Keywords : endpalte current * acetylchcholinesterase Subject RIV: ED - Physiology Impact factor: 1.430, year: 2009

  7. Construction and in vivo evaluation of a dual layered collagenous scaffold with a radial pore structure for repair of the diaphragm

    NARCIS (Netherlands)

    Brouwer, K.M.; Daamen, W.F.; Lochem, N. van; Reijnen, D.; Wijnen, R.M.H.; Kuppevelt, T. van

    2013-01-01

    In each organ the extracellular matrix has a specific architecture and composition, adapted to the functional needs of that organ. As cells are known to respond to matrix organization, biomaterials that take into account the specific architecture of the tissues to be regenerated may have an

  8. Reinnervation of the diaphragm by the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3-5 damage.

    Science.gov (United States)

    Verin, Eric; Morelot-Panzini, Capucine; Gonzalez-Bermejo, Jesus; Veber, Benoit; Perrouin Verbe, Brigitte; Soudrie, Brigitte; Leroi, Anne Marie; Marie, Jean Paul; Similowski, Thomas

    2017-10-01

    The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in humans by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons. Five patients were included. They all had a high level of tetraplegia, with phrenic nerve motor neuron destruction. They were highly dependent on ventilation, without any possibility of weaning. They did not have other chronic pathologies, especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi. One patient was excluded because of a functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing or vocal alterations. In these three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic electromyogram of the right and left hemidiaphragms after 1 year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18-24 months after the reinnervation with excellent results. At 36 months, none of the patients could restore their automatic ventilation. In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any vocal or swallowing complications.

  9. Pressure sensor for high-temperature liquids

    International Nuclear Information System (INIS)

    Forster, G.A.

    1978-01-01

    A pressure sensor for use in measuring pressures in liquid at high temperatures, especially such as liquid sodium or liquid potassium, comprises a soft diaphragm in contact with the liquid. The soft diaphragm is coupled mechanically to a stiff diaphragm. Pressure is measured by measuring the displacement of both diaphragms, typically by measuring the capacitance between the stiff diaphragm and a fixed plate when the stiff diaphragm is deflected in response to the measured pressure through mechanical coupling from the soft diaphragm. Absolute calibration is achieved by admitting gas under pressure to the region between diaphragms and to the region between the stiff diaphragm and the fixed plate, breaking the coupling between the soft and stiff diaphragms. The apparatus can be calibrated rapidly and absolutely

  10. Under - diaphragm irradiation of an osseous stage 4 Hodgkin lymphoma at a patient whose pregnancy was unknown; Irradiation sous-diaphragmatique d'un lymphome hodgkinien de stade 4 osseux chez une patiente dont la grossesse etait meconnue

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, M.V.; Tournier-Rangeard, L.; Brunaud, C.; Marchesi, V.; Peiffert, D. [Centre Alexis-Vautrin, Service de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Bologna, S. [Centre Hospitalier Universitaire Brabois, Service d' Hematologie, 54 - Vandoeuvre-les-Nancy (France)

    2007-11-15

    Four years after the irradiation, the patient was in situation of complete forgiveness: the child was normal, there was neither a deformation nor a mental disorder, but the neoplastic risk persists, thus long-term surveillance is imperative. If the pregnancy is known, we have to arrest the foetal risks incurred in order to propose a termination of pregnancy; therefore, are made the measures on phantoms of the dose that he would receive, according to the tumoral localization, to the dose necessary to eradicate the tumor, to the field and the possible masks for an optimal tumoral control. (N.C.)

  11. Development of bridge girder movement criteria for accelerated bridge construction.

    Science.gov (United States)

    2014-06-01

    End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

  12. The stethoscope: some preliminary investigations

    Science.gov (United States)

    Welsby, P; Parry, G; Smith, D

    2003-01-01

    Textbooks, clinicians, and medical teachers differ as to whether the stethoscope bell or diaphragm should be used for auscultating respiratory sounds at the chest wall. Logic and our results suggest that stethoscope diaphragms are more appropriate. PMID:14707247

  13. Microfabricated pressure and shear stress sensors

    Science.gov (United States)

    Liu, Chang (Inventor); Chen, Jack (Inventor); Engel, Jonathan (Inventor)

    2009-01-01

    A microfabricated pressure sensor. The pressure sensor comprises a raised diaphragm disposed on a substrate. The diaphragm is configured to bend in response to an applied pressure difference. A strain gauge of a conductive material is coupled to a surface of the raised diaphragm and to at least one of the substrate and a piece rigidly connected to the substrate.

  14. Treating hydrocarbon oils

    Energy Technology Data Exchange (ETDEWEB)

    Young, J

    1871-08-11

    An apparatus is illustrated. It consists of a cistern of stone in which an inclined diaphragm is situated. The acid passes in below the inclined diaphragm by the pipe, and having acted upon the oil beneath the diaphragm any unabsorbed portion escapes through the opening at its highest end.

  15. Improvements in or relating to pumps

    International Nuclear Information System (INIS)

    Norman, G.

    1985-01-01

    A diaphragm pump comprises a housing, a diaphragm peripherally secured in the housing and in the form of a laminate, one layer of greater elasticity than another, a rod extending from a central support through a wall of the housing for reciprocating the diaphragm. The central support engages the diaphragm to a transverse extent which is between one half and two thirds of the major transverse active dimension (ie radius) of the diaphragm, at least one of the parts diverging as it extends away from the diaphragm. A control mechanism is illustrated for a pair of pumps driven by one reciprocating piston under the influence of pneumatic pressure, reciprocation and the pump stroke/delivery stroke relationship being controlled by adjustable pressure restrictors acting on change-over spool valves. (author)

  16. The Aerodynamic Behavior of a Harmonically Oscillating Finite Sweptback Wing in Supersonic Flow

    National Research Council Canada - National Science Library

    Chang, Chieh-Chien

    1951-01-01

    By an extension of Evvard's "diaphragm" concept outside the wing tip, the present paper presents two approximate methods for calculating the aerodynamic behavior of harmonically oscillating, sweptback...

  17. A case report on gastric volvulus of a 17 years old boy from Bangladesh

    Directory of Open Access Journals (Sweden)

    M. Tasdik Hasan

    2017-01-01

    Conclusion: It should be suspected in congenital abnormalities of diaphragm and associate with many other congenital abnormalities like ectopic kidney. Early surgical repair remains the treatment of choice.

  18. Natural history of extensive diaphragmatic injury on the right side: experimental study in rats

    Directory of Open Access Journals (Sweden)

    Jorge Henrique Rivaben

    2014-08-01

    Full Text Available OBJECTIVE: To evaluate the natural healing of the rat diaphragm that suffered an extensive right penetrating injury.METHODS: Animals were submitted to an extensive penetrating injury in right diaphragm. The sample consisted of 40 animals. The variables studied were initial weight, weight 21 days after surgery; healing of the diaphragm, non-healing of the diaphragm, and herniated abdominal contents into the chest.RESULTS: Ten animals were used as controls for weight and 30 animals were operated. Two animals died during the experiment, so 28 animals formed the operated group; healing of the diaphragm occurred in 15 animals (54%, 11 other animals showed diaphragmatic hernia (39% and in two we observed only diaphragmatic injury without hernia (7%. Among the herniated organs, the liver was found in 100% of animals, followed by the omentum in 77%, small bowel in 62%, colon in 46%, stomach in 31% and spleen in 15%. The control group and the diaphragmatic healing subgroup showed increased weight since the beginning of the study and the 21 days after surgery (p <0.001. The unhealed group showed no change in weight (p = 0.228.CONCLUSION: there is a predominance of spontaneous healing in the right diaphragm; animals in which there was no healing of the diaphragm did not gain weight, and the liver was the organ present in 100% the diaphragmatic surface in all rats with healed diaphragm or not.

  19. The role of hiatus hernia in gastro-oesophageal reflux disease

    NARCIS (Netherlands)

    van Herwaarden, MA; Samsom, M; Smout, AJPM

    This article gives an overview of the role of sliding hiatus hernia in gastro-oesophageal reflux disease (GORD). The crural diaphragm acts as an external sphincter of the antireflux barrier. Contractions of the crural diaphragm increase lower-oesophageal-sphincter (LOS) pressure during each

  20. The role of hiatus hernia in gastro-oesophageal reflux disease

    NARCIS (Netherlands)

    van Herwaarden, Margot A.; Samsom, Melvin; Smout, André J. P. M.

    2004-01-01

    This article gives an overview of the role of sliding hiatus hernia in gastro-oesophageal reflux disease (GORD). The crural diaphragm acts as an external sphincter of the anti-reflux barrier. Contractions of the crural diaphragm increase lower-oesophageal-sphincter (LOS) pressure during each

  1. Coupling modeling and analysis of a wind energy converter

    Directory of Open Access Journals (Sweden)

    Jie-jie Li

    2016-06-01

    Full Text Available In this article, the numerical simulation of a 2.0-MW wind energy converter coupling is achieved by three-dimensional computer-aided design modeling technique and finite element method. The static performances and the buckling characteristics of the diaphragm coupling are investigated. The diaphragm coupling is divided into three substructures, namely, torque input end, the middle section, and the torque output end. Considering the assembly and contact conditions, the simulation analysis for stress responses of the diaphragm coupling is carried out. The buckling factor and buckling mode of the diaphragms are obtained, and the geometric parameters of the diaphragms are optimized according to their buckling characteristics. The relationship between the pretightening force of the bolts, which tighten the friction flange and the friction plate, and the sliding torque is given by an empirical formula. The reasonable ranges of the pretightening force and tighten torque of the bolts are recommended. The fatigue analysis of the diaphragms is completed, and the results show that the diaphragms are competent to the designed life of the diaphragm coupling.

  2. Influence of deep neuromuscular block on the surgeonś assessment of surgical conditions during laparotomy

    DEFF Research Database (Denmark)

    Madsen, M V; Scheppan, S; Mørk, E

    2017-01-01

    Background: During laparotomy, surgeons may experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. Deep neuromuscular block (NMB), defined as a post-tetanic-count (PTC) between 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesized th...

  3. K-Basin sludge treatment facility pump test report

    International Nuclear Information System (INIS)

    SQUIER, D.M.

    1999-01-01

    Tests of a disc pump and a dual diaphragm pump are stymied by pumping a metal laden fluid. Auxiliary systems added to a diaphragm pump might enable the transfer of such fluids, but the additional system complexity is not desirable for remotely operated and maintained systems

  4. Improving the prognostic value of blunt abdominal trauma scoring ...

    African Journals Online (AJOL)

    Radiographic imaging showed positive signs of trauma (air under diaphragm, elevated copula of diaphragm) in 45 patients. Conclusion Adding a simple radiographic film in the erect position of the abdomen and lower chest markedly improved the prognostic value of the different scoring systems included. Ann Pediatr Surg ...

  5. Thoracoschisis: case report and review of the literature

    African Journals Online (AJOL)

    thin diaphragm, but there was no opening into the pleural cavity. The diaphragm did not appear redundant or to require plication. At this point, the herniated bowel and liver were delivered from the right chest wall defect into the abdomen (Fig. 2). Following this, the respiratory and metabolic acidosis eventually improved.

  6. Two cases of Pentalogy of Cantrell diagnosed antenatally at Korle ...

    African Journals Online (AJOL)

    There was no diaphragm over the liver but a posterior diaphragm over the kidneys. The liver was grossly enlarged with a groove on the upper surface accommodating the heart. The heart was located in the abdominal wall defect, lying freely on top of the liver (Figure 4). Further dissection revealed a Tetralogy of Fallot.

  7. Intra-myocardial Bullet causing heart block in a patient with multiple ...

    African Journals Online (AJOL)

    consolidation and bullet lodged above the diaphragm. The chest radiograph showed bullet lodged above the diaphragm. ARDS resolved markedly over the following. 7 days. However, there were persistent bronchial breath sounds in the left lower lung with purulent secretions and collapse with consolidation. CT scan of the ...

  8. Reconstruction of Complex Post-Traumatic Perineal/Pelvic Defects ...

    African Journals Online (AJOL)

    of the pelvic diaphragm). A composite pedicled. ALT flap was considered adequate for the initial reconstruction and stabilization, with the option of using a free fibular flap later, should the pelvic ring remain unstable. The fascia was used to complete the pelvic ring. It also provided anterior support to the pelvic diaphragm.

  9. ORIGINAL ARTICLE

    African Journals Online (AJOL)

    boaz

    collected using moistened sterile cotton swab from the ear pieces and diaphragms of each stethoscope and processed following standard microbiological techniques. In all, 26 stethoscopes were studied. 46.2% (12) of the diaphragms cultured yielded growth of bacteria while only 11.5% (3) of the ear pieces cultured yielded ...

  10. What Are the Different Types of Contraception?

    Science.gov (United States)

    ... pregnancy, but it should be removed within 24 hours. Traditional latex diaphragms must be the correct size to work properly, and a health care provider can determine the proper fit. A diaphragm should be replaced after 1 or 2 years. Women also need to be measured for a new ...

  11. Congenital pyloric atresia: clinical features, diagnosis, associated ...

    African Journals Online (AJOL)

    Epidermolysis bullosa was seen in eight (40%) patients and multiple intestinal atresias in five (25%). Three patients had associated esophageal atresia. Pyloric diaphragm was the most common and seen in 13 patients including double diaphragms in two followed by pyloric atresia with a gap in four and pyloric atresia ...

  12. A time-selective technique for free-field reciprocity calibration of condenser microphones

    DEFF Research Database (Denmark)

    Barrera Figueroa, Salvador; Rasmussen, Knud; Jacobsen, Finn

    2003-01-01

    In normal practice, microphones are calibrated in a closed coupler where the sound pressure is uniformly distributed over the diaphragm. Alternatively, microphones can be placed in a free field, although in that case the distribution of sound pressure over the diaphragm will change as a result of...

  13. Right diaphragmatic rupture and hepatic hernia: an indirect sign on computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, N.; Nicaise, N.; Struyven, J.; Gansbeke, D. van [Department of Radiology, Hopital Erasme, Brussel (Belgium); DeBacker, D. [Intensive Care Unit, Hopital Erasme, Brussels (Belgium)

    1999-06-01

    We report a case of blunt traumatic right diaphragm rupture with hepatic hernia. The diagnosis was first suggested by an abnormal hepatic location depicted on axial CT. This finding can be considered as a potentially new indirect sign of right diaphragm rupture in patients with blunt trauma. The diagnosis was then confirmed by reformatted CT and MR images. (orig.) With 1 fig., 16 refs.

  14. Right diaphragmatic rupture and hepatic hernia: an indirect sign on computed tomography

    International Nuclear Information System (INIS)

    Sadeghi, N.; Nicaise, N.; Struyven, J.; Gansbeke, D. van; DeBacker, D.

    1999-01-01

    We report a case of blunt traumatic right diaphragm rupture with hepatic hernia. The diagnosis was first suggested by an abnormal hepatic location depicted on axial CT. This finding can be considered as a potentially new indirect sign of right diaphragm rupture in patients with blunt trauma. The diagnosis was then confirmed by reformatted CT and MR images. (orig.)

  15. Effect of straining on diaphragmatic crura with identification of the straining-crural reflex. The "reflex theory" in gastroesophageal competence

    Directory of Open Access Journals (Sweden)

    El Sibai Olfat

    2004-09-01

    Full Text Available Abstract Background The role of the crural diaphragm during increased intra-abdominal pressure is not exactly known. We investigated the hypothesis that the crural diaphragm undergoes reflex phasic contraction on elevation of the intra-abdominal pressure with a resulting increase of the lower esophageal pressure and prevention of gastro-esophageal reflux. Methods The esophageal pressure and crural diaphragm electromyographic responses to straining were recorded in 16 subjects (10 men, 6 women, age 36.6 ± 11.2 SD years during abdominal hernia repair. The electromyogram of crural diaphragm was recorded by needle electrode inserted into the crural diaphragm, and the lower esophageal pressure by a saline-perfused catheter. The study was repeated after crural anesthetization and after crural infiltration with saline. Results The crural diaphragm exhibited resting electromyographic activity which showed a significant increase on sudden (coughing, p Conclusions Straining effected an increase of the electromyographic activity of the crural diaphragm and of the lower esophageal pressure. This effect is suggested to be reflex in nature and to be mediated through the "straining-crural reflex". The crural diaphragm seems to play a role in the lower esophageal competence mechanism. Further studies are required to assess the clinical significance of the current results in gastro-esophageal reflux disease and hiatus hernia.

  16. Three-dimensional multi-physics coupled simulation of ignition transient in a dual pulse solid rocket motor

    Science.gov (United States)

    Li, Yingkun; Chen, Xiong; Xu, Jinsheng; Zhou, Changsheng; Musa, Omer

    2018-05-01

    In this paper, numerical investigation of ignition transient in a dual pulse solid rocket motor has been conducted. An in-house code has been developed in order to solve multi-physics governing equations, including unsteady compressible flow, heat conduction and structural dynamic. The simplified numerical models for solid propellant ignition and combustion have been added. The conventional serial staggered algorithm is adopted to simulate the fluid structure interaction problems in a loosely-coupled manner. The accuracy of the coupling procedure is validated by the behavior of a cantilever panel subjected to a shock wave. Then, the detailed flow field development, flame propagation characteristics, pressure evolution in the combustion chamber, and the structural response of metal diaphragm are analyzed carefully. The burst-time and burst-pressure of the metal diaphragm are also obtained. The individual effects of the igniter's mass flow rate, metal diaphragm thickness and diameter on the ignition transient have been systemically compared. The numerical results show that the evolution of the flow field in the combustion chamber, the temperature distribution on the propellant surface and the pressure loading on the metal diaphragm surface present a strong three-dimensional behavior during the initial ignition stage. The rupture of metal diaphragm is not only related to the magnitude of pressure loading on the diaphragm surface, but also to the history of pressure loading. The metal diaphragm thickness and diameter have a significant effect on the burst-time and burst-pressure of metal diaphragm.

  17. Stress modeling of microdiaphragm pressure sensors

    Science.gov (United States)

    Tack, P. C.; Busta, H. H.

    1986-01-01

    A finite element program analysis was used to model the stress distribution of two monocrystalline silicon diaphragm pressure sensors. One configuration consists of an anisotropically backside etched diaphragm into a 250 micron thick, (100) oriented, silicon wafer. The diaphragm and total chip dimensions are given. The device is rigidly clamped on the back to a support substrate. Another configuration consists of a monocrystalline, (100), microdiaphragm which is formed on top of the wafer and whose area is reduced by a factor of 25 over the first configuration. The diaphragm is rigidly clamped to the silicon wafer. The stresses were calculated at a gauge pressure of 300 mm Hg and used to estimate the piezoresistive responses of resistor elements which were placed parallel and perpendicular near the diaphragm edges.

  18. Development and Testing of a Two-Stage Hybrid Launcher.

    Science.gov (United States)

    1979-10-31

    more unitorm properties thorough the tuicK section by quencning in a salt batn, thereby minimizing the cooling gradient but pruuucing a bainitic steel ...to to 1990 psig with H2 , then 6 capture (embed) steel diaphragm fragments S-1, 11/28/77 Diaphragm To devise a method to seal drivers without * Built...driver along with nyloi S-2, and (plug) using steel diaphragms, which add significant release system, and plug cato S-3 11/29/77 tests amounts of

  19. Effectiveness of diaphragmatic stimulation with single-channel electrodes in rabbits

    Directory of Open Access Journals (Sweden)

    Rodrigo Guellner Ghedini

    2013-06-01

    Full Text Available Every year, a large number of individuals become dependent on mechanical ventilation because of a loss of diaphragm function. The most common causes are cervical spinal trauma and neuromuscular diseases. We have developed an experimental model to evaluate the performance of electrical stimulation of the diaphragm in rabbits using single-channel electrodes implanted directly into the muscle. Various current intensities (10, 16, 20, and 26 mA produced tidal volumes above the baseline value, showing that this model is effective for the study of diaphragm performance at different levels of electrical stimulation

  20. Performance data of the new free-piston shock tunnel T5 at GALCIT

    Science.gov (United States)

    Hornung, H.; Sturtevant, B.; Belanger, J.; Sanderson, S.; Brouillette, M.; Jenkins, M.

    1992-01-01

    A new free piston shock tunnel has been constructed at the Graduate Aeronautical Laboratories at Caltec. Compression tube length is 30 m and diameter 300 mm. Shock tube length is 12 m and diameter 90 mm. Piston mass is 150 kg and maximum diaphragm burst pressure is 130 MPa. Special features of this facility are that the pressure in the driver gas is monitored throughout the compression process until well after diaphragm rupture, and that the diaphragm burst pressure can be measured dynamically. An analysis of initial performance data including transient behavior of the flow over models is presented.

  1. Engineering model cryocooler test results

    International Nuclear Information System (INIS)

    Skimko, M.A.; Stacy, W.D.; McCormick, J.A.

    1992-01-01

    This paper reports that recent testing of diaphragm-defined, Stirling-cycle machines and components has demonstrated cooling performance potential, validated the design code, and confirmed several critical operating characteristics. A breadboard cryocooler was rebuilt and tested from cryogenic to near-ambient cold end temperatures. There was a significant increase in capacity at cryogenic temperatures and the performance results compared will with code predictions at all temperatures. Further testing on a breadboard diaphragm compressor validated the calculated requirement for a minimum axial clearance between diaphragms and mating heads

  2. O efeito facilitatório do óxido nítrico sobre a transmissão neuromuscular de preparações nervo frênico- diafragma isolado de ratos é Ca++ dependente - DOI: 10.4025/actascibiolsci.v26i4.1528 NO- induced neuromuscular facilitation in the phrenic nerve diaphragm preparation of rats is Ca++ dependent - DOI: 10.4025/actascibiolsci.v26i4.1528

    Directory of Open Access Journals (Sweden)

    Heraldo Esheveria Borges

    2004-04-01

    Full Text Available A pesquisa foi conduzida para verificar se os efeitos neuromusculares induzidos por óxido nítrico (NO poderiam depender dos níveis extracelulares de Ca++. O doador de NO, nitroprussiato de sódio (NPS, e o análogo de GMPc, 8-Br-cGMP, aumentaram a amplitude das contrações musculares (ACM em preparações indiretamente estimuladas a 0.2 Hz, mas não produziram efeitos quando a solução nutriente (Krebs normal foi trocada por Krebs com baixo Ca++/ alto Mg++. NPS e 8-Br-cGMP reduziram a ACM quando as preparações foram diretamente estimuladas, mas tal efeito não foi observado com o uso de Krebs com baixo Ca++/ alto Mg++. Dados sugerem que os efeitos neuromusculares induzidos por NO dependem dos níveis extracelulares de Ca++The research was carried out to verify whether the neuromuscular effects induced by nitric oxide (NO might depend on extracellular level of Ca++. The donor of NO, sodium nitroprusside (SNP, and the analogue of cGMP, 8-Br-cGMP, increased the muscular contraction amplitude (MCA in preparations indirectly stimulated at 0.2 Hz, but did not produce any effect when the nutrient solution was exchanged by Krebs buffer low Ca++/ high Mg++. SNP and 8-Br-cGMP reduced the MCA in preparations directly stimulated. Such effect was not recorded in Krebs buffer low Ca++/ high Mg++. Data suggest that the neuromuscular effects induced by NO or cGMP depend on extracellular level of Ca++

  3. Hydrogen by water electrolysis

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Hydrogen production by water electrolysis (aqueous solution of potassium hydroxide) is shortly presented with theoretical aspects (thermodynamics and kinetics), and components of the electrolytic cell (structural materials, cathodes, anodes, diaphragms), and examples of industrial processes. (A.B.). 4 figs

  4. 76 FR 34192 - Commercial and Industrial Pumps

    Science.gov (United States)

    2011-06-13

    ... a specific speed below approximately 90 (4,500). Those having double- suction impellers usually have... three methods: (1) Reciprocating action of plungers, pistons, bellows or diaphragms; (2) Rotary action...

  5. History of Connecticut's short-term strain program for evaluation of steel bridges : July 2009.

    Science.gov (United States)

    2009-07-01

    Non-destructive strain monitoring has been used for two decades on Connecticuts bridges to : supplement visual field inspections. These studies have addressed a wide range of problems, : including fatigue cracking in diaphragm connections, cracked...

  6. A Portable Sorption Tester for Nondestructive Testing of Chemical Protective Garments

    National Research Council Canada - National Science Library

    Kerrin, Stephen

    1992-01-01

    .... A low-boiling halocarbon mimics carbon tetrachloride, the standard test vapor. A very low flow mass flow controller mixes challenge from a pressurized cylinder with a controlled flow of air from a diaphragm pump...

  7. Optical fiber sensors for harsh environments

    Science.gov (United States)

    Xu, Juncheng; Wang, Anbo

    2007-02-06

    A diaphragm optic sensor comprises a ferrule including a bore having an optical fiber disposed therein and a diaphragm attached to the ferrule, the diaphragm being spaced apart from the ferrule to form a Fabry-Perot cavity. The cavity is formed by creating a pit in the ferrule or in the diaphragm. The components of the sensor are preferably welded together, preferably by laser welding. In some embodiments, the entire ferrule is bonded to the fiber along the entire length of the fiber within the ferrule; in other embodiments, only a portion of the ferrule is welded to the fiber. A partial vacuum is preferably formed in the pit. A small piece of optical fiber with a coefficient of thermal expansion chosen to compensate for mismatches between the main fiber and ferrule may be spliced to the end of the fiber.

  8. Исследование пьезодатчика мембранного типа

    OpenAIRE

    Деревягин, Г.

    2010-01-01

    Comsol Multiphysics modeling is used in the analysis of influence of piezoelectric disc diameter and thickness of diaphragm on the characteristics of piezoelectric sensors. The results are applied in the sensor designed for ultrasonic gas flow rate metering system.

  9. Medline Plus

    Full Text Available ... lungs. During expiration, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. As a result, the lungs contract and air is forced out.

  10. Medline Plus

    Full Text Available ... inhalation) and expiration (exhalation). During inspiration, the diaphragm contracts and pulls downward while the muscles between the ribs contract and pull upward. This increases the size of ...

  11. Medline Plus

    Full Text Available ... upward. This increases the size of the thoracic cavity and decreases the pressure inside. As a result, ... diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. As ...

  12. NIGERIAN VETERINARY JOURNAL

    African Journals Online (AJOL)

    ADEYEYE

    dysfunction, rupture of the diaphragm causes loss of parietal ... automobile accident. The bitch ... with anaesthetic monitoring (Gradyet 9200,. China) machine containing both a pulse oximeter and .... intestines had already occurred which may.

  13. Sexual Health

    Science.gov (United States)

    ... Stop Myself From Having a Wet Dream? Gynecomastia Hernias How to Do a Testicular Self-Exam (Slideshow) ... Spermicide Talking to Your Partner About Condoms The Cervical Cap The Diaphragm The IUD Withdrawal About Us ...

  14. Active Control of Radiated Sound With Integrated Piezoelectric Composite Structures. Volume 3 Appendices (Concl.)

    National Research Council Canada - National Science Library

    Fuller, Christopher

    1998-01-01

    ... covered with an acoustic diaphragm configured in a flextensional type manner. The resultant PANEL source after many iterations of analysis, development, construction and testing was found to provide amplification ratios of around 250...

  15. Active Control of Radiated Sound with Integrated Piezoelectric Composite Structures. Volume 1

    National Research Council Canada - National Science Library

    Fuller, Christopher

    1998-01-01

    ... covered with an acoustic diaphragm configured in a flextensional type manner. The resultant PANEL source after many iterations of analysis, development, construction and testing was found to provide amplification ratios of around 250...

  16. Active Control of Radiated Sound With Integrated Piezoelectric Composite Structures. Volume 3: Appendices (Concl.)

    National Research Council Canada - National Science Library

    Fuller, Christopher

    1998-01-01

    ... covered with an acoustic diaphragm configured in a flextensional type manner. The resultant PANEL source after many iterations of analysis, development, construction and testing was found to provide amplification ratios of around 250...

  17. Truncus coeliacus-kompressionssyndrom

    DEFF Research Database (Denmark)

    Ghulam, Qasam M.; Bredahl, Kim K; Axelsen, Thomas

    2015-01-01

    of diaphragm, compresses the coeliac trunk thus causing stenosis and malperfusion of the gastrointestinal organs. Until recently, there has been some reluctance to consider intervention with revascularization or ligament release. Within the latest decade minimally invasive techniques, including laparoscopic...

  18. Reduced Acetylcholine Receptor Density, Morphological Remodeling, and Butyrylcholinesterase Activity Can Sustain Muscle Function in Acetylcholinesterase Knockout Mice

    National Research Council Canada - National Science Library

    Adler, Michael; Manley, Heather A; Deshpande, Sharad S; Hamilton, Tracey A; Kan, Robert K; Oyler, George; Lockridge, Oksana; Duysen, Ellen G; Sheridan, Robert E

    2004-01-01

    ...) and can survive into adulthood. Twitch tensions elicited in diaphragms of AChE-/- mice by single supramaximal stimuli had larger amplitudes and slower rise and decay times than did those in wild-type animals...

  19. Microfabricated Ice-Detection Sensor

    National Research Council Canada - National Science Library

    DeAnna, Russell

    1997-01-01

    .... The sensor is capable of distinguishing between an ice covered and a clean surface. It employs a bulk micromachined wafer with a 7 micrometers thick, boron doped, silicon diaphragm which serves as one plate of a parallel plate capacitor...

  20. Truncus coeliacus-kompressionssyndrom

    DEFF Research Database (Denmark)

    Ghulam, Qasam M; Bredahl, Kim K; Axelsen, Thomas

    2016-01-01

    of diaphragm, compresses the coeliac trunk thus causing stenosis and malperfusion of the gastrointestinal organs. Until recently, there has been some reluctance to consider intervention with revascularization or ligament release. Within the latest decade minimally invasive techniques, including laparoscopic...

  1. On the application of a simple model of cobalt-60 beams

    International Nuclear Information System (INIS)

    Gantchew, M.G.

    1979-01-01

    The simple mathematical model of the dose distribution in a phantom irradiated by a single beam of cobalt-60 gamma rays (Wilks, R.J., and Sutcliffe, J.F., 1977, Phys. Med. Biol., vol. 22, 737) requires measurements for each particular field size and diaphragm setting to describe the decrement functions (dose distributions along a straight line perpendicular to the central ray). Measurements made with a Gammatron-3 have shown satisfactory agreement between computed and measured lateral dose distributions for different diaphragm settings if the experimental data was first subjected to additional processing, and Wilks and Sutcliffe's model can therefore be applied to any diaphragm setting using this modification. Field sizes can therefore be entered according to diaphragm indicator reading in dose planning. (U.K.)

  2. 42 CFR 486.108 - Condition for coverage: Safety standards.

    Science.gov (United States)

    2010-10-01

    ...—restriction of the useful beam. Diaphragms, cones, or adjustable collimators are used to restrict the useful... other individual regularly used for this service. Care is taken to assure that pregnant women do not...

  3. Pneumatic wrench retains or discharges nuts or bolts as desired

    Science.gov (United States)

    Bouille, J. R.

    1966-01-01

    Pneumatic wrench grips, screws or unscrews, and discharges a nut or bolt as desired. The device consists of a standard pneumatic wrench modified with a special hex bolt head socket assembly and a diaphragm air cylinder.

  4. Effectiveness of Family Planning Methods

    Science.gov (United States)

    ... women in a year Effectiveness of Family Planning Methods Implant Reversible Intrauterine Device (IUD) Permanent Male Sterilization ... 0.5 % Diaphragm 12 % How to make your method most effective After procedure, little or nothing to ...

  5. A scalable pressure sensor based on an electrothermally and electrostatically operated resonator

    KAUST Repository

    Hajjaj, Amal Z.; Alcheikh, Nouha; Hafiz, Md Abdullah Al; Ilyas, Saad; Younis, Mohammad I.

    2017-01-01

    We present a pressure sensor based on the convective cooling of the air surrounding an electrothermally heated resonant bridge. Unlike conventional pressure sensors that rely on diaphragm deformation in response to pressure, the sensor does

  6. Thoracic surgery in solving enormous elevation of the left hemidiaphragm

    Directory of Open Access Journals (Sweden)

    Cvijanović Vlado

    2007-01-01

    Full Text Available Background. Acquired elevation of the diaphragm is mostly the result of phrenic nerve paralysis, some of thoracic and abdominal patological states, and also some of neuromuscular diseases. Surgical treatment is rarely performed and is indicated when lung compression produces disabilitating dyspnea, and includes plication of diaphragm. The goal of this case report has been to show completely documented diagnostic procedures and surgical treatment one of rare pathological condition. Case report. A 62-year-old patient was admitted to our clinic because of surgical treatment of the enormous elevation of the left hemidiaphragm. After thoracotomy and plication of the bulging diaphragm, lung compression did not exist any more and mediastinum went back in the normal position. Conclusion. Elevation of the diaphragm rarely demands surgical correction. When it is complicated with lung compression and disabilitating dyspnea, surgical treatment has extremely useful functional effect.

  7. Experimental study of micro-shock tube flow

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin Ouk; Kim, Gyu Wan; Rasel, Md. Alim Iftakhar [Dept. of Mechanical Engineering, Andong National University, Andong (Korea, Republic of); Kim, Heuy Dong [Fire Research Center, Korea Institute of Civil Engineering and Building Technology, Hwasung (Korea, Republic of)

    2015-03-15

    The flow characteristics in micro shock tube are investigated experimentally. Studies were carried out using a stainless steel micro shock tube. Shock and expansion wave was measured using 8 pressure sensors. The initial pressure ratio was varied from 4.3 to 30.5, and the diameter of tube was also changed from 3 mm to 6 mm. Diaphragm conditions were varied using two types of diaphragms. The results obtained show that the shock strength in the tube becomes stronger for an increase in the initial pressure ratio and diameter of tube. For the thinner diaphragm, the highest shock strength was found among varied diaphragm condition. Shock attenuation was highly influenced by the diameter of tube.

  8. Assisted Ventilation in Patients with Acute Respiratory Distress Syndrome: Lung-distending Pressure and Patient-Ventilator Interaction

    NARCIS (Netherlands)

    Doorduin, J.; Sinderby, C.A.; Beck, J.; Hoeven, J.G. van der; Heunks, L.M.

    2015-01-01

    BACKGROUND: In patients with acute respiratory distress syndrome (ARDS), the use of assisted mechanical ventilation is a subject of debate. Assisted ventilation has benefits over controlled ventilation, such as preserved diaphragm function and improved oxygenation. Therefore, higher level of

  9. Thoracic Insufficiency Syndrome

    Science.gov (United States)

    ... properly, and the diaphragm muscle must be properly anchored at the base of the chest. With fused ... waist to help stabilize the surgically expanded chest wall constriction (expansion thoracoplasty). To accommodate later growth, the ...

  10. Inflammatory monocytes promote progression of Duchenne muscular dystrophy and can be therapeutically targeted via CCR2

    OpenAIRE

    Mojumdar, Kamalika; Liang, Feng; Giordano, Christian; Lemaire, Christian; Danialou, Gawiyou; Okazaki, Tatsuma; Bourdon, Johanne; Rafei, Moutih; Galipeau, Jacques; Divangahi, Maziar; Petrof, Basil J

    2014-01-01

    Myofiber necrosis and fibrosis are hallmarks of Duchenne muscular dystrophy (DMD), leading to lethal weakness of the diaphragm. Macrophages (MPs) are required for successful muscle regeneration, but the role of inflammatory monocyte (MO)-derived MPs in either promoting or mitigating DMD is unclear. We show that DMD (mdx) mouse diaphragms exhibit greatly increased expression of CCR2 and its chemokine ligands, along with inflammatory (Ly6Chigh) MO recruitment and accumulation of CD11bhigh MO-de...

  11. Wet-steam erosion of steam turbine disks and shafts

    International Nuclear Information System (INIS)

    Averkina, N. V.; Zheleznyak, I. V.; Kachuriner, Yu. Ya.; Nosovitskii, I. A.; Orlik, V. G.; Shishkin, V. I.

    2011-01-01

    A study of wet-steam erosion of the disks and the rotor bosses or housings of turbines in thermal and nuclear power plants shows that the rate of wear does not depend on the diagrammed degree of moisture, but is determined by moisture condensing on the surfaces of the diaphragms and steam inlet components. Renovating the diaphragm seals as an assembly with condensate removal provides a manifold reduction in the erosion.

  12. X fluorescence spectrometer including at least one toroidal monochromator with logarithmic spiral

    International Nuclear Information System (INIS)

    Florestan, J.

    1986-01-01

    This spectrometer includes a X-ray source, an entrance diaphragm, a revolution monochromator with monocrystal thin plates and a seal set in its center, an outer diaphragm and a X-ray detector. A second monochromator can be set between the source and the sample. The thin plates are set so as to be a toroidal ring whose cross section in an axial plane describes a logarithmic spiral [fr

  13. Participação dos nervos intercostais na inervação do diafragma de gatos (Felis catus, Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Marcelo Domingues de Faria

    2011-08-01

    Full Text Available The knowledge of organism's anatomy is essential to conduct any experiment or study with itself. Based on that, we decided to analyze and study in details the innervation of the diaphragm muscle from intercostal nerves in cats. It goes beyond other authors' analysis that describes only the innervation from phrenic nerves. Despite we have got a range of results, we observed a major frequency of eighth to tenth intercostal nerves going to diaphragm muscle.

  14. SU-G-JeP4-12: Real-Time Organ Motion Monitoring Using Ultrasound and KV Fluoroscopy During Lung SBRT Delivery

    International Nuclear Information System (INIS)

    Omari, E; Tai, A; Li, X; Cooper, D; Lachaine, M

    2016-01-01

    Purpose: Real-time ultrasound monitoring during SBRT is advantageous in understanding and identifying motion irregularities which may cause geometric misses. In this work, we propose to utilize real-time ultrasound to track the diaphragm in conjunction with periodical kV fluoroscopy to monitor motion of tumor or landmarks during SBRT delivery. Methods: Transabdominal Ultrasound (TAUS) b-mode images were collected from 10 healthy volunteers using the Clarity Autoscan System (Elekta). The autoscan transducer, which has a center frequency of 5 MHz, was utilized for the scans. The acquired images were contoured using the Clarity Automatic Fusion and Contouring workstation software. Monitoring sessions of 5 minute length were observed and recorded. The position correlation between tumor and diaphragm could be established with periodic kV fluoroscopy periodically acquired during treatment with Elekta XVI. We acquired data using a tissue mimicking ultrasound phantom with embedded spheres placed on a motion stand using ultrasound and kV Fluoroscopy. MIM software was utilized for image fusion. Correlation of diaphragm and target motion was also validated using 4D-MRI and 4D-CBCT. Results: The diaphragm was visualized as a hyperechoic region on the TAUS b-mode images. Volunteer set-up can be adjusted such that TAUS probe will not interfere with treatment beams. A segment of the diaphragm was contoured and selected as our tracking structure. Successful monitoring sessions of the diaphragm were recorded. For some volunteers, diaphragm motion over 2 times larger than the initial motion has been observed during tracking. For the phantom study, we were able to register the 2D kV Fluoroscopy with the US images for position comparison. Conclusion: We demonstrated the feasibility of tracking the diaphragm using real-time ultrasound. Real-time tracking can help in identifying such irregularities in the respiratory motion which is correlated to tumor motion. We also showed the

  15. Use of 90% ethanol to decontaminate stethoscopes in resource limited settings

    OpenAIRE

    Raghubanshi, Bijendra Raj; Sapkota, Supriya; Adhikari, Arjab; Dutta, Aman; Bhattarai, Utsuk; Bhandari, Rastriyata

    2017-01-01

    Abstract Background In developing countries like Nepal, 90% ethanol is cheap and is available in most hospitals. The unavailability of isopropyl alcohol (IPA) in these settings led us to compare the efficacy between 90% ethanol and isopropyl alcohol pads in reducing the bacterial contamination of diaphragm of stethoscope. Methods A randomized blinded experimental study was carried out to determine the difference between cleaning stethoscopes with 90% ethanol and IPA. Cultures of diaphragm wer...

  16. Endometriosis-related spontaneous diaphragmatic rupture.

    Science.gov (United States)

    Triponez, Frédéric; Alifano, Marco; Bobbio, Antonio; Regnard, Jean-François

    2010-10-01

    Non-traumatic, spontaneous diaphragmatic rupture is a rare event whose pathophysiology is not known. We report the case of endometriosis-related spontaneous rupture of the right diaphragm with intrathoracic herniation of the liver, gallbladder and colon. We hypothesize that the invasiveness of endometriotic tissue caused diaphragm fragility, which finally lead to its complete rupture without traumatic event. The treatment consisted of a classical management of diaphragmatic rupture, with excision of the endometriotic nodule followed by medical ovarian suppression for six months.

  17. Abelson tyrosine-protein kinase 2 Regulates Myoblast Proliferation and Controls Muscle Fiber Length

    OpenAIRE

    Burden, Steven; Lee, Jennifer

    2017-01-01

    Muscle fiber length is nearly uniform within a muscle but widely different among muscles. Here, we show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm and other muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of available myoblasts and leading to increased myoblast fusion. Abl2 acts in myoblasts, but expansion of the diaphragm ...

  18. Complete eventration of right hemidiaphragm: A rare presentation

    Directory of Open Access Journals (Sweden)

    Krushna Makwana

    2017-01-01

    Full Text Available Eventration of the diaphragm is a term used to describe an abnormal elevation of part or whole of the hemidiaphragm, where the whole or part of the diaphragm is made up of a thin fibro membranous sheet replacing normal diaphragmatic musculature. Complete and partial eventration both can occur, however, complete eventration of the right hemidiaphragm in an adult female, as presented in this patient, is rarely seen.

  19. Rare small intestinal volvulus from entrapment in hepato-diaphragmatic adhesions in a 45-year-old lady.

    Science.gov (United States)

    Olaoye, Iyiade Olatunde; Adesina, Micheal Dapo

    2016-12-20

    Small intestinal volvulus is rare in adults and rarely caused by string adhesions between the liver and the diaphragm. Similar adhesions were described in Fitz-Hugh-Curtis syndrome. We report a 45-year-old lady with small intestinal volvulus from entrapment of a loop in string adhesions between the liver and the diaphragm. Her plain radiographs showed a significant shadow of the trapped loop. Published by Oxford University Press and JSCR Publishing Ltd. All rights reserved. © The Author 2016.

  20. Development of Orally Bioavailable Therapeutics by the Chloroplast Expression System to Counter Muscle Degeneration, Weakness, and Fibrosis in DMD

    Science.gov (United States)

    2016-11-01

    strength in the diaphragm muscles . However, by 2 months of treatment the benefits were reduced back to untreated controls. We are continuing to analyze...Enzyme 2 Angiotensin-(1-7) Fibrosis Duchenne Muscular Dystrophy Mdx Skeletal muscle Chloroplast expression Oral bioavailability 3... treatment regimen to determine if any acute functional benefit was achieved. While no significant improvement was observed in EDL muscles , the diaphragms

  1. [Persistent duodenal septum in an adult].

    Science.gov (United States)

    Helwing, E; Echtermeyer, V; Otten, G

    1977-02-01

    A case of duodenal obstruction by a congenital duodenal web in a 34-year-old woman is presented. A mucosal diaphragm obstructed the duodenum. It showed an excentric opening of 0.8 cm diameter, but the dilated diaphragm caused a total stop during the last months. Despite a typical history, exact X-ray, and endoscopic examination, the correct preoperative diagnosis was not found, because nobody thought it possible, that a mucosal diapharm of the duodenum could persist for 34 years.

  2. The effects of area contraction on the performance of UNITEN's shock tube: Numerical study

    International Nuclear Information System (INIS)

    Mohsen, A M; Yusoff, M Z; Al-Falahi, A

    2013-01-01

    Numerical study into the effects of area contraction on shock tube performance has been reported in this paper. The shock tube is an important component of high speed fluid flow test facility was designed and built at the Universiti Tenaga Nasional (UNITEN). In the above mentioned facility, a small area contraction, in form of a bush, was placed adjacent to the diaphragm section to facilitate the diaphragm rupturing process when the pressure ratio across the diaphragm increases to a certain value. To investigate the effects of the small area contraction on facility performance, numerical simulations were conducted at different operating conditions (diaphragm pressure ratios P 4 /P 1 of 10, 15, and 20). A two-dimensional time-accurate Navier-Stokes CFD solver was used to simulate the transient flow in the facility with and without area contraction. The numerical results show that the facility performance is influenced by area contraction in the diaphragm section. For instance, when operating the facility with area contraction using diaphragm pressure ratio (P 4 /P 1 ) of 10, the shock wave strength and shock wave speed decrease by 18% and 8% respectively.

  3. Contribution of 5-HT2A receptors on diaphragmatic recovery after chronic cervical spinal cord injury.

    Science.gov (United States)

    Lee, Kun-Ze; Gonzalez-Rothi, Elisa J

    2017-10-01

    Unilateral C2 spinal cord hemisection (C2Hx) interrupts bulbospinal respiratory pathways innervating ipsilateral phrenic motoneurons, resulting in cessation of ipsilateral diaphragm motor output. Plasticity within the spinal neural circuitry controlling the diaphragm can induce partial recovery of phrenic bursting which correlates with the time-dependent return of spinal serotonin (5-HT) immunoreactivity in the vicinity of phrenic motoneurons. The 5-HT 2A receptor subtype is present on phrenic motoneurons and its expression is up-regulated after cervical spinal cord injury; however the functional role of these receptors following injury has not been clearly defined. The present study evaluated the functional role of 5-HT 2A receptors by testing the hypothesis that pharmacologic blockade would attenuate diaphragm activity in rats with chronic cervical spinal cord injury. Bilateral diaphragm electromyography (EMG) was performed in vagal-intact and spontaneously breathing rats before and after intravenous administration of the 5-HT 2A receptor antagonist Ketanserin (1mg/kg). Intravenous ketanserin significantly attenuated ipsilateral diaphragm EMG activity in C2Hx animals but had no impact on diaphragm output in uninjured animals. We conclude that 5-HT 2A receptor activation contributes to the recovery of ipsilateral phrenic motor output after chronic cervical spinal cord injury. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Specific features of two diffraction schemes for a widely divergent X-ray beam

    Energy Technology Data Exchange (ETDEWEB)

    Avetyan, K. T.; Levonyan, L. V.; Semerjian, H. S.; Arakelyan, M. M., E-mail: marakelyan@ysu.am; Badalyan, O. M. [Yerevan State University (Armenia)

    2015-03-15

    We investigated the specific features of two diffraction schemes for a widely divergent X-ray beam that use a circular diaphragm 30–50 μm in diameter as a point source of characteristic radiation. In one of the schemes, the diaphragm was set in front of the crystal (the diaphragm-crystal (d-c) scheme); in the other, it was installed behind the crystal (the crystal-diaphragm (c-d) scheme). It was established that the diffraction image in the c-d scheme is a topographic map of the investigated crystal area. In the d-c scheme at L = 2l (l and L are the distances between the crystal and the diaphragm and between the photographic plate and the diaphragm, respectively), the branches of hyperbolas formed in this family of planes (hkl) by the characteristic K{sub α} and K{sub β} radiations, including higher order reflections, converge into one straight line. It is experimentally demonstrated that this convergence is very sensitive to structural inhomogeneities in the crystal under study.

  5. Micro-Scalable Thermal Control Device

    Science.gov (United States)

    Moran, Matthew E. (Inventor)

    2002-01-01

    A microscalable thermal control module consists of a Stirling cycle cooler that can be manipulated to operate at a selected temperature within the heating and cooling range of the module. The microscalable thermal control module is particularly suited for controlling the temperature of devices that must be maintained at precise temperatures. It is particularly suited for controlling the temperature of devices that need to be alternately heated or cooled. The module contains upper and lower opposing diaphragms, with a regenerator region containing a plurality of regenerators interposed between the diaphragms. Gaps exist on each side of each diaphragm to permit it to oscillate freely. The gap on the interior side one diaphragm is in fluid connection with the gap on the interior side of the other diaphragm through regenerators. As the diaphragms oscillate working gas is forced through the regenerators. The surface area of each regenerator is sufficiently large to effectively transfer thermal energy to and from the working gas as it is passed through them. The phase and amplitude of the oscillations can be manipulated electronically to control the steady state temperature of the active thermal control surface, and to switch the operation of the module from cooling to heating, or vice versa. The ability of the microscalable thermal control module to heat and cool may be enhanced by operating a plurality of modules in series, in parallel, or in connection through a shared bottom layer.

  6. Experimental design and analysis for piezoelectric circular actuators in flow control applications

    International Nuclear Information System (INIS)

    Mane, Poorna; Mossi, Karla; Bryant, Robert

    2008-01-01

    Flow control can lead to saving millions of dollars in fuel costs each year by making an aircraft more efficient. Synthetic jets, a device for active flow control, operate by introducing small amounts of energy locally to achieve non-local changes in the flow field with large performance gains. These devices consist of a cavity with an oscillating diaphragm that divides it into active and passive sides. The active side has a small opening where a jet is formed, while the passive side does not directly participate in the fluidic jet. Over the years, research has shown that synthetic jet behavior is dependent on the active diaphragm and the cavity design; hence, the focus of this work. The performance of the synthetic jet is studied under various factors related to the diaphragm and the cavity geometry. Three diaphragms, manufactured from piezoelectric composites, were selected for this study: Bimorph, Thunder ® and Lipca. The overall factors considered are the driving signals, voltage, frequency, cavity height, orifice size, and passive cavity pressure. Using the average maximum jet velocity as the response variable, these factors are individually studied for each actuator, and statistical analysis tools are used to select the relevant factors in the response variable. The factors are divided into two experimental fractional factorial design matrices, with five and four factors, respectively. Both experiments are chosen to be of resolution V, where main factors are confounded with three-factor interactions. In the first experimental design, the results show that frequency is not a significant factor, while waveform is significant for all the actuators. In addition, the magnitude of the regression coefficients suggests that a model that includes the diaphragm as a factor may be possible. These results are valid within the ranges tested, that is low frequencies and sawtooth and sine waveform as driving signals. In the second experimental design, cavity dimensions are

  7. Energetic optimization of a piezo-based touch-operated button for man–machine interfaces

    International Nuclear Information System (INIS)

    Sun, Hao; De Vries, Theo J A; De Vries, Rene; Van Dalen, Harry

    2012-01-01

    This paper discusses the optimization of a touch-operated button for man–machine interfaces based on piezoelectric energy harvesting techniques. In the mechanical button, a common piezoelectric diaphragm, is assembled to harvest the ambient energy from the source, i.e. the operator’s touch. Under touch force load, the integrated diaphragm will have a bending deformation. Then, its mechanical strain is converted into the required electrical energy by means of the piezoelectric effect presented to the diaphragm. Structural design (i) makes the piezoceramic work under static compressive stress instead of static or dynamic tensile stress, (ii) achieves a satisfactory stress level and (iii) provides the diaphragm and the button with a fatigue lifetime in excess of millions of touch operations. To improve the button’s function, the effect of some key properties consisting of dimension, boundary condition and load condition on electrical behavior of the piezoelectric diaphragm are evaluated by electromechanical coupling analysis in ANSYS. The finite element analysis (FEA) results indicate that the modification of these properties could enhance the diaphragm significantly. Based on the key properties’ different contributions to the improvement of the diaphragm’s electrical energy output, they are incorporated into the piezoelectric diaphragm’s redesign or the structural design of the piezo-based button. The comparison of the original structure and the optimal result shows that electrical energy stored in the diaphragm and the voltage output are increased by 1576% and 120%, respectively, and the volume of the piezoceramic is reduced to 33.6%. These results will be adopted to update the design of the self-powered button, thus enabling a large decrease of energy consumption and lifetime cost of the MMI. (paper)

  8. Cortical Reorganization in Dual Innervation by Single Peripheral Nerve.

    Science.gov (United States)

    Zheng, Mou-Xiong; Shen, Yun-Dong; Hua, Xu-Yun; Hou, Ao-Lin; Zhu, Yi; Xu, Wen-Dong

    2017-09-21

    Functional recovery after peripheral nerve injury and repair is related with cortical reorganization. However, the mechanism of innervating dual targets by 1 donor nerve is largely unknown. To investigate the cortical reorganization when the phrenic nerve simultaneously innervates the diaphragm and biceps. Total brachial plexus (C5-T1) injury rats were repaired by phrenic nerve-musculocutaneous nerve transfer with end-to-side (n = 15) or end-to-end (n = 15) neurorrhaphy. Brachial plexus avulsion (n = 5) and sham surgery (n = 5) rats were included for control. Behavioral observation, electromyography, and histologic studies were used for confirming peripheral nerve reinnervation. Cortical representations of the diaphragm and reinnervated biceps were studied by intracortical microstimulation techniques before and at months 0.5, 3, 5, 7, and 10 after surgery. At month 0.5 after complete brachial plexus injury, the motor representation of the injured forelimb disappeared. The diaphragm representation was preserved in the "end-to-side" group but absent in the "end-to-end" group. Rhythmic contraction of biceps appeared in "end-to-end" and "end-to-side" groups, and the biceps representation reappeared in the original biceps and diaphragm areas at months 3 and 5. At month 10, it was completely located in the original biceps area in the "end-to-end" group. Part of the biceps representation remained in the original diaphragm area in the "end-to-side" group. Destroying the contralateral motor cortex did not eliminate respiration-related contraction of biceps. The brain tends to resume biceps representation from the original diaphragm area to the original biceps area following phrenic nerve transfer. The original diaphragm area partly preserves reinnervated biceps representation after end-to-side transfer. Copyright © 2017 by the Congress of Neurological Surgeons

  9. Sensorimotor control of breathing in the mdx mouse model of Duchenne muscular dystrophy.

    Science.gov (United States)

    Burns, David P; Roy, Arijit; Lucking, Eric F; McDonald, Fiona B; Gray, Sam; Wilson, Richard J; Edge, Deirdre; O'Halloran, Ken D

    2017-11-01

    Respiratory failure is a leading cause of mortality in Duchenne muscular dystrophy (DMD), but little is known about the control of breathing in DMD and animal models. We show that young (8 weeks of age) mdx mice hypoventilate during basal breathing due to reduced tidal volume. Basal CO 2 production is equivalent in wild-type and mdx mice. We show that carotid bodies from mdx mice have blunted responses to hyperoxia, revealing hypoactivity in normoxia. However, carotid body, ventilatory and metabolic responses to hypoxia are equivalent in wild-type and mdx mice. Our study revealed profound muscle weakness and muscle fibre remodelling in young mdx diaphragm, suggesting severe mechanical disadvantage in mdx mice at an early age. Our novel finding of potentiated neural motor drive to breathe in mdx mice during maximal chemoactivation suggests compensatory neuroplasticity enhancing respiratory motor output to the diaphragm and probably other accessory muscles. Patients with Duchenne muscular dystrophy (DMD) hypoventilate with consequential arterial blood gas derangement relevant to disease progression. Whereas deficits in DMD diaphragm are recognized, there is a paucity of knowledge in respect of the neural control of breathing in dystrophinopathies. We sought to perform an analysis of respiratory control in a model of DMD, the mdx mouse. In 8-week-old male wild-type and mdx mice, ventilation and metabolism, carotid body afferent activity, diaphragm muscle force-generating capacity, and muscle fibre size, distribution and centronucleation were determined. Diaphragm EMG activity and responsiveness to chemostimulation was determined. During normoxia, mdx mice hypoventilated, owing to a reduction in tidal volume. Basal CO 2 production was not different between wild-type and mdx mice. Carotid sinus nerve responses to hyperoxia were blunted in mdx, suggesting hypoactivity. However, carotid body, ventilatory and metabolic responses to hypoxia were equivalent in wild-type and

  10. Dynamically balanced, hydraulically driven compressor/pump apparatus for resonant free piston Stirling engines

    Science.gov (United States)

    Corey, John A.

    1984-05-29

    A compressor, pump, or alternator apparatus is designed for use with a resonant free piston Stirling engine so as to isolate apparatus fluid from the periodically pressurized working fluid of the Stirling engine. The apparatus housing has a first side closed by a power coupling flexible diaphragm (the engine working member) and a second side closed by a flexible diaphragm gas spring. A reciprocally movable piston is disposed in a transverse cylinder in the housing and moves substantially at right angles relative to the flexible diaphragms. An incompressible fluid fills the housing which is divided into two separate chambers by suitable ports. One chamber provides fluid coupling between the power diaphragm of the RFPSE and the piston and the second chamber provides fluid coupling between the gas spring diaphragm and the opposite side of the piston. The working members of a gas compressor, pump, or alternator are driven by the piston. Sealing and wearing parts of the apparatus are mounted at the external ends of the transverse cylinder in a double acting arrangement for accessibility. An annular counterweight is mounted externally of the reciprocally movable piston and is driven by incompressible fluid coupling in a direction opposite to the piston so as to damp out transverse vibrations.

  11. Analysis of Poiseuille Flow Property in Two-Dimensional Mi-cro Channels of Microfluidic Pneumatic Micro-Valve

    Science.gov (United States)

    Yang, Shaohua; Long, Wei; Chen, Yajun

    2018-03-01

    In this paper, the control mechanism and mathematical description of the microfluidic flow in the microfluidic process of the PDMS membrane type pneumatic micro-valve were studied. The velocity and pressure variation law of the velocity field inside micro valve was analyzed by numerical simulation method. The influence of the two kinds of inlet drive modes on the working effect and the pressure flow characteristics of the pneumatic micro-valve was studied. The structure of the elastic solid valve diaphragm under the dual action of the airway and the liquid channel was analyzed. Deformation and stress distribution. The results show that the gas flow in the gas flow channel under the diaphragm by the vacuum part of the role of the formation of a suction gas vortex, pressure-driven mode was easier under the diaphragm to produce a strong gas vortex, resulting in internal and external pressure to promote diaphragm cut-off liquid channel; In the pressure pneumatic mode, the stress at both ends of the diaphragm was smaller, the membrane was not easy to tear failure.

  12. DESIGN AND OPTIMIZATION OF VALVELESS MICROPUMPS BY USING GENETIC ALGORITHMS APPROACH

    Directory of Open Access Journals (Sweden)

    AIDA F. M. SHUKUR

    2015-10-01

    Full Text Available This paper presents a design optimization of valveless micropump using Genetic Algorithms (GA. The micropump is designed with a diaphragm, pumping chamber and diffuser/nozzle element functions as inlet and outlet of micropump with outer dimension of (5×1.75×5 mm3. The main objectives of this research are to determine the optimum pressure to be applied at micropump’s diaphragm and to find the optimum coupling parameters of the micropump to achieve high flow rate with low power consumption. In order to determine the micropump design performance, the total deformation, strain energy density, equivalent stress for diaphragm, velocity and net flow rate of micropump are investigated. An optimal resonant frequency range for the diaphragm of valveless micropump is obtained through the result assessment. With the development of GA-ANSYS model, a maximum total displacement of diaphragm, 5.3635 µm, with 12 kPa actuation pressure and optimum net flowrate of 7.467 mL/min are achieved.

  13. Application of Fluorescence Two-Dimensional Difference In-Gel Electrophoresis as a Proteomic Biomarker Discovery Tool in Muscular Dystrophy Research

    Science.gov (United States)

    Carberry, Steven; Zweyer, Margit; Swandulla, Dieter; Ohlendieck, Kay

    2013-01-01

    In this article, we illustrate the application of difference in-gel electrophoresis for the proteomic analysis of dystrophic skeletal muscle. The mdx diaphragm was used as a tissue model of dystrophinopathy. Two-dimensional gel electrophoresis is a widely employed protein separation method in proteomic investigations. Although two-dimensional gels usually underestimate the cellular presence of very high molecular mass proteins, integral membrane proteins and low copy number proteins, this method is extremely powerful in the comprehensive analysis of contractile proteins, metabolic enzymes, structural proteins and molecular chaperones. This gives rise to two-dimensional gel electrophoretic separation as the method of choice for studying contractile tissues in health and disease. For comparative studies, fluorescence difference in-gel electrophoresis has been shown to provide an excellent biomarker discovery tool. Since aged diaphragm fibres from the mdx mouse model of Duchenne muscular dystrophy closely resemble the human pathology, we have carried out a mass spectrometry-based comparison of the naturally aged diaphragm versus the senescent dystrophic diaphragm. The proteomic comparison of wild type versus mdx diaphragm resulted in the identification of 84 altered protein species. Novel molecular insights into dystrophic changes suggest increased cellular stress, impaired calcium buffering, cytostructural alterations and disturbances of mitochondrial metabolism in dystrophin-deficient muscle tissue. PMID:24833232

  14. Regional thermal specialisation in a mammal: temperature affects power output of core muscle more than that of peripheral muscle in adult mice (Mus musculus).

    Science.gov (United States)

    James, Rob S; Tallis, Jason; Angilletta, Michael J

    2015-01-01

    In endotherms, such as mammals and birds, internal organs can specialise to function within a narrow thermal range. Consequently, these organs should become more sensitive to changes in body temperature. Yet, organs at the periphery of the body still experience considerable fluctuations in temperature, which could select for lower thermal sensitivity. We hypothesised that the performance of soleus muscle taken from the leg would depend less on temperature than would the performance of diaphragm muscle taken from the body core. Soleus and diaphragm muscles were isolated from mice and subjected to isometric and work-loop studies to analyse mechanical performance at temperatures between 15 and 40 °C. Across this thermal range, soleus muscle took longer to generate isometric force and longer to relax, and tended to produce greater normalised maximal force (stress) than did diaphragm muscle. The time required to produce half of maximal force during isometric tetanus and the time required to relax half of maximal force were both more sensitive to temperature in soleus than they were in diaphragm. However, thermal sensitivities of maximal force during isometric tetani were similar for both muscles. Consistent with our hypothesis, power output (the product of speed and force) was greater in magnitude and more thermally sensitive in diaphragm than it was in soleus. Our findings, when combined with previous observations of muscles from regionally endothermic fish, suggest that endothermy influences the thermal sensitivities of power output in core and peripheral muscles.

  15. Microwave bonding of MWNTs and fabrication of a low-cost, high-performance polymer pressure sensor

    International Nuclear Information System (INIS)

    Gau, C; Chen, H T; Ko, H S

    2010-01-01

    This paper describes the fabrication of a simple, low-cost pressure sensor that can be readily mass produced. Microwave-induced heating is used to bond a multiwall carbon nanotube (MWNT) network to a poly(ethylene terephthalate) substrate that serves as a pressure diaphragm. The MWNT network can be patterned with a damascene process and used as the sensor material. The pressure diaphragm with the MWNT network can be bonded with any flexible substrate pre-drilled with a cavity that allows a deflection of the diaphragm. Design and fabrication considerations for the sensor are discussed and its performance is demonstrated and evaluated. The sensor is thermally stable and has a much higher sensitivity and gauge factor than polysilicon sensors. In addition to the simple fabrication process, the sensor can be widely applied and integrated into microfluidic systems or biochips where pressure information is required.

  16. Characterization of Piezoelectric Actuators for Flow Control over a Wing

    Science.gov (United States)

    Mossi, Karla M.; Bryant, Robert G.

    2004-01-01

    During the past decade, piezoelectric actuators as the active element in synthetic jets demonstrated that they could significantly enhance the overall lift on an airfoil. However, durability, system weight, size, and power have limited their use outside a laboratory. These problems are not trivial, since piezoelectric actuators are physically brittle and display limited displacement. The objective of this study is to characterize the relevant properties for the design of a synthetic jet utilizing three types of piezoelectric actuators as mechanical diaphragms, Radial Field Diaphragms, Thunders, and Bimorphs so that the shape cavity volume does not exceed 147.5 cubic centimeters on a 7centimeter x 7centimeter aerial coverage. These piezoelectric elements were selected because of their geometry, and overall free-displacement. Each actuator was affixed about its perimeter in a cavity, and relevant parameters such as clamped displacement variations with voltage and frequency, air velocities produced through an aperture, and sound pressure levels produced by the piezoelectric diaphragms were measured.

  17. [Phrenic nerve stimulation protects against mechanical ventilation-induced diaphragmatic dysfunction through myogenic regulatory factors].

    Science.gov (United States)

    An, G H; Chen, M; Zhan, W F; Hu, B; Zhang, H X

    2018-02-12

    Objective: To explore the protective effect of electrical stimulation of phrenic nerve on diaphragmatic function during mechanical ventilation. Methods: Forty healthy adult SD rats were randomly divided into 5 groups: blank control group (BC), spontaneous breathing group (SB), electrical stimulation group (ES), mechanical ventilation group (MV), and electrical stimulation and mechanical ventilation group (MS). The rats in each group were treated for 18 h except for the BC group. After treatment, the diaphragm muscle tissue was obtained and the diaphragm contractility including peak-to-peak value(Vpp) and maximum rate of contraction(+ dT/dt max) were measured. Expression of MyoD and myogenin were detected. Results: Except for the ES and the MS groups, there was a significant difference for peak-to-peak value (Vpp) between each 2 groups ( P mechanical ventilation induced diaphragmatic function damage, and therefore plays a protective effect on the diaphragm.

  18. Experience with valves for PHWR reactors

    International Nuclear Information System (INIS)

    Narayan, K.; Mhetre, S.G.

    1977-01-01

    Material specifications and inspection and testing requirements of the valves meant for use in nuclear reactors are mentioned. In the heavy water systems (both primary and moderator) of a PHWR type reactor, the valves used are gate valves, globe valves, diaphragm valves, butterfly valves, check valves and relief valves. Their locations and functions they perform in the Rajasthan Atomic Power Station Unit-1 are described. Experience with them is given. The major problems encountered with them have been : (1) leakage from the stem seals and body bonnet joint, (2) leakage due to failure of diaphragm and/or washout of the packing and (3) malfunctioning. Measures taken to solve these are discussed. Finally a mention has been made of improved versions of valves, namely, metal diaphragm valve and inverted relief valve. (M.G.B.)

  19. Device for measuring the tritium concentration in a measuring gas

    International Nuclear Information System (INIS)

    Koran, P.

    1987-01-01

    The measuring gas is brought into contact via a measuring gas path with a diaphragm permeable to water, which separates the measuring gas path from a counter gas path leading to a proportional detector. The measuring gas path and the counter gas path are in counterflow in the area of diaphragm. The preferably hose diaphragm consists of a well-known ion exchange material, which can be used for gas drying purposes, which is permeable to water and tritium compounds similar to water, but is impermeable to other gases and liquids contained in air, particularly rare gases. In this way, the tritium concentration can be measured with great rare gas suppression. (orig./HP) [de

  20. Uncooled tunneling infrared sensor

    Science.gov (United States)

    Kenny, Thomas W. (Inventor); Kaiser, William J. (Inventor); Podosek, Judith A. (Inventor); Vote, Erika C. (Inventor); Muller, Richard E. (Inventor); Maker, Paul D. (Inventor)

    1995-01-01

    An uncooled infrared tunneling sensor in which the only moving part is a diaphragm which is deflected into contact with a micromachined silicon tip electrode prepared by a novel lithographic process. Similarly prepared deflection electrodes employ electrostatic force to control the deflection of a silicon nitride, flat diaphragm membrane. The diaphragm exhibits a high resonant frequency which reduces the sensor's sensitivity to vibration. A high bandwidth feedback circuit controls the tunneling current by adjusting the deflection voltage to maintain a constant deflection of the membrane. The resulting infrared sensor can be miniaturized to pixel dimensions smaller than 100 .mu.m. An alternative embodiment is implemented using a corrugated membrane to permit large deflection without complicated clamping and high deflection voltages. The alternative embodiment also employs a pinhole aperture in a membrane to accommodate environmental temperature variation and a sealed chamber to eliminate environmental contamination of the tunneling electrodes and undesireable accoustic coupling to the sensor.

  1. Composite slab behavior and strength analysis under static and dynamic loads

    Directory of Open Access Journals (Sweden)

    Florin Radu HARIGA

    2012-07-01

    Full Text Available Steel-framed buildings are typically constructed using steel-deck-reinforced concrete floor slabs. The in-plane (or diaphragm strength and stiffness of the floor system are frequently utilized in the lateral load-resisting system design. This paper presents the results of an experimental research program in which four full size composite diaphragms were vertically loaded to the limit state, under static or dynamic loads. Two test specimens were provided with longitudinal steel-deck ribs, and the other two specimens with cross steel-deck ribs. Typical composite diaphragm limit states are described, and the controlling limit state for each of the full size tests is indicated. The interaction effects between the reinforced concrete slab and the steel girder on the composite slab strength and stiffness were mainly studied.

  2. Neuromuscular blockade for improvement of surgical conditions during laparotomy

    DEFF Research Database (Denmark)

    Madsen, Matias Vested; Scheppan, Susanne; Kissmeyer, Peter

    2015-01-01

    INTRODUCTION: During laparotomy, surgeons frequently experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. This issue is particularly pertinent while closing the fascia and placing the intestines into the abdominal cavity. Establishment of a deep neuromus......INTRODUCTION: During laparotomy, surgeons frequently experience difficult surgical conditions if the patient's abdominal wall or diaphragm is tense. This issue is particularly pertinent while closing the fascia and placing the intestines into the abdominal cavity. Establishment of a deep...... neuromuscular blockade (NMB), defined as a post-tetanic-count (PTC) of 0-1, paralyses the abdominal wall muscles and the diaphragm. We hypothesised that deep NMB (PTC 0-1) would improve surgical conditions during upper laparotomy as compared to standard NMB with bolus administration. METHODS...

  3. Modelling measurement microphones using BEM with visco-thermal losses

    DEFF Research Database (Denmark)

    Cutanda Henriquez, Vicente; Juhl, Peter Møller

    2012-01-01

    For many decades, models that can explain the behaviour of measurement condenser microphones have been proposed in the literature. These devices have an apparently simple working principle, a charged capacitor whose charge varies when one of its electrodes, the diaphragm, moves as a result of sound...... waves. However, measurement microphones must be manufactured very carefully due to their sensitivity to small changes of their physical parameters. There are different elements in a microphone, the diaphragm, the gap behind it, a back cavity, a vent for pressure equalization and an external medium. All...... visco-thermal losses is used to model measurement condenser microphones. The models presented are fully coupled and include a FEM model of the diaphragm. The behaviour of the acoustic variables in the gap and the effect of the pressure equalization vent are discussed, as well as the practical difficulty...

  4. Effect of upper costal and costo-diaphragmatic breathing types on electromyographic activity of respiratory muscles.

    Science.gov (United States)

    Celhay, Isabel; Cordova, Rosa; Miralles, Rodolfo; Meza, Francisco; Erices, Pia; Barrientos, Camilo; Valenzuela, Saúl

    2015-04-01

    To compare electromyographic (EMG) activity in young-adult subjects with different breathing types. This study included 50 healthy male subjects with complete natural dentition, and no history of orofacial pain or craniomandibular-cervical-spinal disorders. Subjects were classified into two groups: upper costal breathing type, and costo-diaphragmatic breathing. Bipolar surface electrodes were located on sternocleidomastoid, diaphragm, external intercostal, and latissimus dorsi muscles. Electromyographic activity was recorded during the following tasks: (1) normal quiet breathing; (2) speaking the word 'Mississippi'; (3) swallowing saliva; and (4) forced deep breathing. Sternocleidomastoid and latissimus dorsi EMG activity was not significantly different between breathing types, whereas diaphragm and external intercostal EMG activity was significantly higher in the upper costal than costo-diaphragmatic breathing type in all tasks (P<0·05; Wilcoxon signed rank-sum test). Diaphragm and external intercostal EMG activity suggests that there could be differences in motor unit recruitment strategies depending on the breathing type.

  5. Design, simulation and analysis of piezoresistive MEMS pressure sensor for fast reactor applications

    International Nuclear Information System (INIS)

    Patankar, Mahesh Kumar; Murali, N.; Satya Murty, S.A.V.; Kalyana Rao, K.; Sridhar, S.

    2013-01-01

    To exploit the extraordinary benefits of MEMS technology in fast reactor domain, a piezoresistive MEMS pressure sensor was designed, simulated and analyzed using Intellisuite Software to measure the RCB air pressure in 0 - 1.25 bar (a) range. For sensing the pressure, a thin square silicon diaphragm of size of 800 x 800 μm 2 with thickness of 20 μm was optimized using FEM analysis and to transfer the mechanical stress, induce in the diaphragm due to pressure, into electrical output voltage signal, a set of piezoresistors were arranged on top side of the diaphragm in full active wheatstone bridge configuration for obtaining the higher sensitivity. The simulation results were compared with the analytical results which were found in line of expectations and electrical sensitivity was obtained at 15 mV/V.bar. (author)

  6. The risk of iatrogenic pneumothorax after electromyography.

    Science.gov (United States)

    Kassardjian, Charles D; O'gorman, Cullen M; Sorenson, Eric J

    2016-04-01

    Pneumothorax is a potentially serious complication of electromyography (EMG). Data on the frequency of pneumothorax after EMG are lacking. The purpose of this study was to determine the frequency, timing, and risk factors for iatrogenic pneumothorax after EMG. Cases of pneumothorax after EMG were reviewed for clinical, electrophysiological, and radiological data. Of 64,490 EMG studies, 7 patients had an association between the EMG and pneumothorax. All patients were symptomatic and presented within 24 hours of EMG. Sampling of serratus anterior and diaphragm was causative in 1 patient each. In 5 patients, multiple high-risk muscles were sampled. The highest frequency of pneumothorax was observed with examination of serratus anterior (0.445%) and diaphragm (0.149%). The frequency of symptomatic iatrogenic pneumothorax after EMG appears to be low, and examinations of serratus anterior and diaphragm carry the highest risk. Electromyographers should be aware of the risk of pneumothorax and should counsel patients accordingly. © 2015 Wiley Periodicals, Inc.

  7. Left-Sided Catamenial Pneumothorax with Thoracic Endometriosis and Bullae in the Alveolar Wall.

    Science.gov (United States)

    Takahashi, Ryo; Kurihara, Masatoshi; Mizobuchi, Teruaki; Ebana, Hiroki; Yamanaka, Sumitaka

    2017-04-20

    Catamenial pneumothorax (CP) is generally caused by intraperitoneal air leaking from the uterus into the thoracic cavity via a defect in the endometrial tissue of the diaphragm and is usually detected in the right thorax. We report a case of left-sided CP caused by endometriosis in the visceral pleura and with no abnormal findings in the diaphragm. A 33-year-old female patient presented at the end of a course of low-dose contraceptive pills for pelvic endometriosis, with spontaneous pneumothorax in the left chest. Chest CT revealed a bulla in the left upper lung lobe. The patient underwent partial resection of the lung. Immunohistochemistry confirmed the presence of endometrial stromal tissue in the visceral pleura and confirmed this as the cause of pneumothorax since there were no observable abnormalities in the diaphragm. This case suggests that immunohistochemical examination of patients with spontaneous pneumothorax can detect alternative endometrial lesions.

  8. Diaphragmatic hernia repair using a rectus abdominis muscle pedicle flap in three dogs.

    Science.gov (United States)

    Chantawong, P; Komin, K; Banlunara, W; Kalpravidh, M

    2013-01-01

    To report the clinical use of a pedicle flap from the rectus abdominis muscle to repair extensive diaphragmatic tears in dogs with diaphragmatic hernia. Three dogs with a combination of radial and circumferential diaphragmatic tears were studied. The circumferential tear was repaired by suturing the wound edge with the edge at the abdominal wall. A pedicle flap of the rectus abdominis muscle was used for repairing the radial tear. The dogs were examined radiographically for lung and diaphragm appearance and evidence of reherniation at 10 days, and at one, two, and four months after surgery, and fluoroscopically for paradoxical motion of the diaphragm at one and four months. The rectus abdominis muscle pedicle flap was successfully used in all three dogs. The animals recovered uneventfully without evidence of reherniation during the four follow-up months. Fluoroscopic examination revealed no paradoxical motion of the diaphragm. A rectus abdominis muscle pedicle flap can be used for repairing large diaphragmatic defects in dogs.

  9. Abelson tyrosine-protein kinase 2 regulates myoblast proliferation and controls muscle fiber length.

    Science.gov (United States)

    Lee, Jennifer K; Hallock, Peter T; Burden, Steven J

    2017-12-12

    Muscle fiber length is nearly uniform within a muscle but widely different among different muscles. We show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm, intercostal and levator auris muscles but not limb muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of myoblasts and leading to increased myoblast fusion. Abl2 acts in myoblasts, but as a consequence of expansion of the diaphragm muscle, the diaphragm central tendon is reduced in size, likely contributing to reduced stamina of Abl2 mutant mice. Ectopic muscle islands, each composed of myofibers of uniform length and orientation, form within the central tendon of Abl2 +/- mice. Specialized tendon cells, resembling tendon cells at myotendinous junctions, form at the ends of these muscle islands, suggesting that myofibers induce differentiation of tendon cells, which reciprocally regulate myofiber length and orientation.

  10. Retrograde Neuroanatomical Tracing of Phrenic Motor Neurons in Mice.

    Science.gov (United States)

    Vandeweerd, Jean-Michel; Hontoir, Fanny; De Knoop, Alexis; De Swert, Kathleen; Nicaise, Charles

    2018-02-22

    Phrenic motor neurons are cervical motor neurons originating from C3 to C6 levels in most mammalian species. Axonal projections converge into phrenic nerves innervating the respiratory diaphragm. In spinal cord slices, phrenic motor neurons cannot be identified from other motor neurons on morphological or biochemical criteria. We provide the description of procedures for visualizing phrenic motor neuron cell bodies in mice, following intrapleural injections of cholera toxin subunit beta (CTB) conjugated to a fluorophore. This fluorescent neuroanatomical tracer has the ability to be caught up at the diaphragm neuromuscular junction, be carried retrogradely along the phrenic axons and reach the phrenic cell bodies. Two methodological approaches of intrapleural CTB delivery are compared: transdiaphragmatic versus transthoracic injections. Both approaches are successful and result in similar number of CTB-labeled phrenic motor neurons. In conclusion, these techniques can be applied to visualize or quantify the phrenic motor neurons in various experimental studies such as those focused on the diaphragm-phrenic circuitry.

  11. Anatomy and physiology of phrenic afferent neurons.

    Science.gov (United States)

    Nair, Jayakrishnan; Streeter, Kristi A; Turner, Sara M F; Sunshine, Michael D; Bolser, Donald C; Fox, Emily J; Davenport, Paul W; Fuller, David D

    2017-12-01

    Large-diameter myelinated phrenic afferents discharge in phase with diaphragm contraction, and smaller diameter fibers discharge across the respiratory cycle. In this article, we review the phrenic afferent literature and highlight areas in need of further study. We conclude that 1 ) activation of both myelinated and nonmyelinated phrenic sensory afferents can influence respiratory motor output on a breath-by-breath basis; 2 ) the relative impact of phrenic afferents substantially increases with diaphragm work and fatigue; 3 ) activation of phrenic afferents has a powerful impact on sympathetic motor outflow, and 4 ) phrenic afferents contribute to diaphragm somatosensation and the conscious perception of breathing. Much remains to be learned regarding the spinal and supraspinal distribution and synaptic contacts of myelinated and nonmyelinated phrenic afferents. Similarly, very little is known regarding the potential role of phrenic afferent neurons in triggering or modulating expression of respiratory neuroplasticity. Copyright © 2017 the American Physiological Society.

  12. Review of technical issues related to the failure of Rosemount pressure transmitters due to fill oil loss. Final report

    International Nuclear Information System (INIS)

    James, R.W.; Gaertner, J.P.; Burns, E.T.; Horn, A.; Lee, L.K.

    1994-08-01

    Rosemount pressure transmitters are extensively used in both safety and non-safety applications in US nuclear power plants. They are used to measure pressure, flow, and water level. Rosemount pressure transmitter models 1151, 1152, 1153A, 1153, and 1154 use a fill oil to hydraulically transmit process pressure exerted on outer isolating diaphragms to internal diaphragms. The resulting deflection of the internal diaphragms changes the distance between them and a central diaphragm separating the transmitter interior into two volumes. The change in distance is measured as a change in electrical capacitance between the isolating diaphragms and the central diaphragm and can be related to differential pressure. The fill oil also functions as a dielectric. It has been well established that this fill oil can potentially leak over time, decreasing transmitter accuracy and increasing transmitter response time. Ultimately, the transmitter can fail. An extensive effort has been expended by the nuclear power industry collectively to analyze this issue and develop technically sound and reasonable requirements to mitigate the effects of oil loss in Rosemount pressure transmitters. Despite this, technical concerns have still been raised regarding the technical validity of the past analyses of this problem and its scope. In May 1993, the NRC created an internal group to comprehensively review the Rosemount issue and the NRC's action in addressing it to ensure that all available technical information has been considered. Because this issue remains of active technical interest and because the past work on this subject has been done by many different groups and organizations, EPRI has prepared this report to thoroughly document the current technical understanding of this issue, to perform additional analysis, and to identify any appropriate additional technical research activities regarding oil loss in Rosemount pressure transmitters

  13. Phrenic motor unit recruitment during ventilatory and non-ventilatory behaviors.

    Science.gov (United States)

    Mantilla, Carlos B; Sieck, Gary C

    2011-10-15

    Phrenic motoneurons are located in the cervical spinal cord and innervate the diaphragm muscle, the main inspiratory muscle in mammals. Similar to other skeletal muscles, phrenic motoneurons and diaphragm muscle fibers form motor units which are the final element of neuromotor control. In addition to their role in sustaining ventilation, phrenic motor units are active in other non-ventilatory behaviors important for airway clearance such as coughing or sneezing. Diaphragm muscle fibers comprise all fiber types and are commonly classified based on expression of contractile proteins including myosin heavy chain isoforms. Although there are differences in contractile and fatigue properties across motor units, there is a matching of properties for the motor neuron and muscle fibers within a motor unit. Motor units are generally recruited in order such that fatigue-resistant motor units are recruited earlier and more often than more fatigable motor units. Thus, in sustaining ventilation, fatigue-resistant motor units are likely required. Based on a series of studies in cats, hamsters and rats, an orderly model of motor unit recruitment was proposed that takes into consideration the maximum forces generated by single type-identified diaphragm muscle fibers as well as the proportion of the different motor unit types. Using this model, eupnea can be accomplished by activation of only slow-twitch diaphragm motor units and only a subset of fast-twitch, fatigue-resistant units. Activation of fast-twitch fatigable motor units only becomes necessary when accomplishing tasks that require greater force generation by the diaphragm muscle, e.g., sneezing and coughing. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Assessment of cardiac exposure in left-tangential breast irradiation

    International Nuclear Information System (INIS)

    Vees, H.; Bigler, R.; Gruber, G.; Bieri, S.

    2011-01-01

    Purpose. - To assess the value of treatment-planning related parameters namely, the breast volume; the distance of the inferior field border to diaphragm; and the cardio-thoracic ratio for left-tangential breast irradiation. Patients and methods. - Treatment plans of 27 consecutively left-sided breast cancer patients after breast conserving surgery were evaluated for several parameters concerning heart-irradiation. We measured the heart distance respective to the cardio-thoracic ratio and the distance of the inferior field border to diaphragm, as well as the breast volume in correlation with the irradiated heart volume. Results. - The mean heart and left breast volumes were 504 cm 3 and 672.8 cm 3 , respectively. The mean heart diameter was 13.4 cm; the mean cardio-thoracic ratio 0.51 and the mean distance of the inferior field border to diaphragm was 1.4 cm. Cardio-thoracic ratio (p = 0.01), breast volume (p = 0.0002), distance of the inferior field border to diaphragm (p = 0.02) and central lung distance (p = 0.02) were significantly correlated with the measured heart distance. A significant correlation was also found between cardio-thoracic ratio, breast volume and distance of the inferior field border to diaphragm with the irradiated heart volume measured by V10, V20 and V40. Conclusion. - The verification of parameters like cardio-thoracic ratio, distance of the inferior field border to diaphragm and breast volume in left-sided breast cancer patients may help in determining which patients could benefit from more complex planning techniques such as intensity-modulated radiotherapy to reduced risk of late cardiac injury. (authors)

  15. An Evaluation of Two Internal Surrogates for Determining the Three-Dimensional Position of Peripheral Lung Tumors

    International Nuclear Information System (INIS)

    Spoelstra, Femke; Soernsen de Koste, John R. van; Vincent, Andrew; Cuijpers, Johan P.; Slotman, Ben J.; Senan, Suresh

    2009-01-01

    Purpose: Both carina and diaphragm positions have been used as surrogates during respiratory-gated radiotherapy. We studied the correlation of both surrogates with three-dimensional (3D) tumor position. Methods and Materials: A total of 59 repeat artifact-free four-dimensional (4D) computed tomography (CT) scans, acquired during uncoached breathing, were identified in 23 patients with Stage I lung cancer. Repeat scans were co-registered to the initial 4D CT scan, and tumor, carina, and ipsilateral diaphragm were manually contoured in all phases of each 4D CT data set. Correlation between positions of carina and diaphragm with 3D tumor position was studied by use of log-likelihood ratio statistics. Models to predict 3D tumor position from internal surrogates at end inspiration (EI) and end expiration (EE) were developed, and model accuracy was tested by calculating SDs of differences between predicted and actual tumor positions. Results: Motion of both the carina and diaphragm significantly correlated with tumor motion, but log-likelihood ratios indicated that the carina was more predictive for tumor position. When craniocaudal tumor position was predicted by use of craniocaudal carina positions, the SDs of the differences between the predicted and observed positions were 2.2 mm and 2.4 mm at EI and EE, respectively. The corresponding SDs derived with the diaphragm positions were 3.7 mm and 3.9 mm at EI and EE, respectively. Prediction errors in the other directions were comparable. Prediction accuracy was similar at EI and EE. Conclusions: The carina is a better surrogate of 3D tumor position than diaphragm position. Because residual prediction errors were observed in this analysis, additional studies will be performed using audio-coached scans.

  16. Prolonged mechanical ventilation alters the expression pattern of angio-neogenetic factors in a pre-clinical rat model.

    Directory of Open Access Journals (Sweden)

    Christian S Bruells

    Full Text Available OBJECTIVE: Mechanical ventilation (MV is a life saving intervention for patients with respiratory failure. Even after 6 hours of MV, diaphragm atrophy and dysfunction (collectively referred to as ventilator-induced diaphragmatic dysfunction, VIDD occurs in concert with a blunted blood flow and oxygen delivery. The regulation of hypoxia sensitive factors (i.e. hypoxia inducible factor 1α, 2α (HIF-1α,-2α, vascular endothelial growth factor (VEGF and angio-neogenetic factors (angiopoietin 1-3, Ang might contribute to reactive and compensatory alterations in diaphragm muscle. METHODS: Male Wistar rats (n = 8 were ventilated for 24 hours or directly sacrificed (n = 8, diaphragm and mixed gastrocnemius muscle tissue was removed. Quantitative real time PCR and western blot analyses were performed to detect changes in angio-neogenetic factors and inflammatory markers. Tissues were stained using Isolectin (IB 4 to determine capillarity and calculate the capillary/fiber ratio. RESULTS: MV resulted in up-regulation of Ang 2 and HIF-1α mRNA in both diaphragm and gastrocnemius, while VEGF mRNA was down-regulated in both tissues. HIF-2α mRNA was reduced in both tissues, while GLUT 4 mRNA was increased in gastrocnemius and reduced in diaphragm samples. Protein levels of VEGF, HIF-1α, -2α and 4 did not change significantly. Additionally, inflammatory cytokine mRNA (Interleukin (IL-6, IL-1β and TNF α were elevated in diaphragm tissue. CONCLUSION: The results demonstrate that 24 hrs of MV and the associated limb disuse induce an up-regulation of angio-neogenetic factors that are connected to HIF-1α. Changes in HIF-1α expression may be due to several interactions occurring during MV.

  17. Prospective Heart Tracking for Whole-heart Magnetic Resonance Angiography

    Science.gov (United States)

    Moghari, Mehdi H.; Geva, Tal; Powell, Andrew J.

    2015-01-01

    Purpose To develop a prospective respiratory-gating technique (Heart-NAV) for use with contrast-enhanced 3D inversion recovery (IR) whole-heart magnetic resonance angiography (MRA) acquisitions that directly tracks heart motion without creating image inflow artifact. Methods With Heart-NAV, 1 of the startup pulses for the whole-heart steady-state free precession MRA sequence is used to collect the centerline of k-space, and its 1-dimensional reconstruction is fed into the standard diaphragm-navigator (NAV) signal analysis process to prospectively gate and track respiratory-induced heart displacement. Ten healthy volunteers underwent non-contrast whole-heart MRA acquisitions using the conventional diaphragm-NAV and Heart-NAV with 5 and 10 mm acceptance windows in a 1.5T scanner. Five patients underwent contrast-enhanced IR whole-heart MRA using a diaphragm-NAV and Heart-NAV with a 5 mm acceptance window. Results For non-contrast whole-heart MRA with both the 5 and 10 mm acceptance windows, Heart-NAV yielded coronary artery vessel sharpness and subjective visual scores that were not significantly different than those using a conventional diaphragm-NAV. Scan time for Heart-NAV was 10% shorter (p<0.05). In patients undergoing contrast-enhanced IR whole-heart MRA, inflow artifact was seen with the diaphragm-NAV but not with Heart-NAV. Conclusion Compared to a conventional diaphragm-NAV, Heart-NAV achieves similar image quality in a slightly shorter scan time and eliminates inflow artifact. PMID:26843458

  18. Sildenafil reduces respiratory muscle weakness and fibrosis in the mdx mouse model of Duchenne muscular dystrophy.

    Science.gov (United States)

    Percival, Justin M; Whitehead, Nicholas P; Adams, Marvin E; Adamo, Candace M; Beavo, Joseph A; Froehner, Stanley C

    2012-09-01

    Duchenne muscular dystrophy (DMD) is the most common form of muscular dystrophy caused by mutations in the dystrophin gene. Loss of dystrophin initiates a progressive decline in skeletal muscle integrity and contractile capacity which weakens respiratory muscles including the diaphragm, culminating in respiratory failure, the leading cause of morbidity and mortality in DMD patients. At present, corticosteroid treatment is the primary pharmacological intervention in DMD, but has limited efficacy and adverse side effects. Thus, there is an urgent need for new safe, cost-effective, and rapidly implementable treatments that slow disease progression. One promising new approach is the amplification of nitric oxide-cyclic guanosine monophosphate (NO-cGMP) signalling pathways with phosphodiesterase 5 (PDE5) inhibitors. PDE5 inhibitors serve to amplify NO signalling that is attenuated in many neuromuscular diseases including DMD. We report here that a 14-week treatment of the mdx mouse model of DMD with the PDE5 inhibitor sildenafil (Viagra(®), Revatio(®)) significantly reduced mdx diaphragm muscle weakness without impacting fatigue resistance. In addition to enhancing respiratory muscle contractility, sildenafil also promoted normal extracellular matrix organization. PDE5 inhibition slowed the establishment of mdx diaphragm fibrosis and reduced matrix metalloproteinase-13 (MMP-13) expression. Sildenafil also normalized the expression of the pro-fibrotic (and pro-inflammatory) cytokine tumour necrosis factor α (TNFα). Sildenafil-treated mdx diaphragms accumulated significantly less Evans Blue tracer dye than untreated controls, which is also indicative of improved diaphragm muscle health. We conclude that sildenafil-mediated PDE5 inhibition significantly reduces diaphragm respiratory muscle dysfunction and pathology in the mdx mouse model of Duchenne muscular dystrophy. This study provides new insights into the therapeutic utility of targeting defects in NO

  19. Chitosan tubes can restore the function of resected phrenic nerves.

    Science.gov (United States)

    Tanaka, Nobuyoshi; Matsumoto, Isao; Suzuki, Mitsutaka; Kaneko, Mami; Nitta, Kanae; Seguchi, Ryuta; Ooi, Akishi; Takemura, Hirofumi

    2015-07-01

    We previously reported that the phrenic nerve could be morphologically repaired by implantation of a chitosan nanofibre tube (C-tube). In the current study, we investigated whether implantation of C-tubes could improve the function of an injured phrenic nerve using a beagle dog model. Seven beagle dogs underwent right thoracotomy under general anaesthesia. An approximately 5 mm length of the right phrenic nerve was resected. Five dogs had a C-tube implantation (C-tube group) and other two dogs did not have the C-tube implantation (control group). Diaphragm movements were longitudinally measured by X-ray fluoroscopy before surgery, immediately after the surgery, and 3, 6 and 12 months after the surgery. The diaphragm movement was determined by diaphragm levels at inspiration and expiration phases, and the excursion difference between them was calculated. At 12 months after the surgery, rethoracotomy was performed to examine electrical phrenic nerve conduction. The C-tube and phrenic nerve were then excised for histological assessment of nerve regeneration. Three of the five animals of the C-tube group showed improvement of diaphragm movement with time. In these three animals, slow phrenic nerve conduction was observed. Histological assessment showed that the injured nerve was connected by newly regenerating nerve fibres surrounded by granulation tissue within the C-tube. On the other hand, the animals in the control group and two animals of the C-tube group showed neither improved diaphragm movement, nor electrical conduction to the diaphragm. No nerve fibre regeneration was found by histology. Our results suggest that, in addition to morphological improvement, C-tube implantation can functionally improve the injured phrenic nerve by promoting phrenic nerve regeneration. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  20. Reduced phrenic motoneuron recruitment during sustained inspiratory threshold loading compared to single-breath loading: a twitch interpolation study

    Directory of Open Access Journals (Sweden)

    Mathieu Raux

    2016-11-01

    Full Text Available In humans, inspiratory constraints engage cortical networks involving the supplementary motor area. Functional magnetic resonance imaging (fMRI shows that the spread and intensity of the corresponding respiratory-related cortical activation dramatically decrease when a discrete load becomes sustained. This has been interpreted as reflecting motor cortical reorganisation and automatisation, but could proceed from sensory and/or affective habituation. To corroborate the existence of motor reorganisation between single-breath and sustained inspiratory loading (namely changes in motor neurones recruitment, we conducted a diaphragm twitch interpolation study based on the hypothesis that motor reorganisation should result in changes in the twitch interpolation slope. Fourteen healthy subjects (age: 21 – 40 years were studied. Bilateral phrenic stimulation was delivered at rest, upon prepared and targeted voluntary inspiratory efforts (vol, upon unprepared inspiratory efforts against a single-breath inspiratory threshold load (single-breath, and upon sustained inspiratory efforts against the same type of load (continuous. The slope of the relationship between diaphragm twitch transdiaphragmatic pressure and the underlying transdiaphragmatic pressure was –1.1 ± 0.2 during vol, –1.5 ± 0.7 during single-breath, and -0.6 ± 0.4 during continuous (all slopes expressed in percent of baseline.percent of baseline-1 all comparisons significant at the 5% level. The contribution of the diaphragm to inspiration, as assessed by the gastric pressure to transdiaphragmatic pressure ratio, was 31 ± 17 % during vol, 22 ± 16 % during single-breath (p=0.13, and 19 ± 9 % during continuous (p = 0.0015 vs. vol. This study shows that the relationship between the amplitude of the transdiaphragmatic pressure produced by a diaphragm twitch and its counterpart produced by the underlying diaphragm contraction is not unequivocal. If twitch interpolation is interpreted as