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Sample records for a1 pulley release

  1. Trigger Finger Release With Stepwise Preservation of the A1 Pulley: A Functional Pulley-Preserving Technique

    PubMed Central

    Niumsawatt, Vachara; Mao, David; Salerno, Stephen; Rozen, Warren M.

    2013-01-01

    The first annular (A1) pulley is an important structure of the hand, providing a biomechanical support to the metacarpophalangeal joint and maintaining joint stability and flexor tendon alignment. Albeit uncommon, disruption of this pulley can result in dislocation or ulnar drift of the digit, particularly pronounced in patients with rheumatoid arthritis. Despite this, the A1 pulley is commonly divided without reconstruction in trigger finger. Several annular pulley reconstructive techniques have been developed to preserve its function. However, development of recurrent triggering has been observed due to fibrosis, largely due to inadequate release of the pulley. We have developed a technique to increase the volume within the flexor sheath while preserving the A1 pulley by way of stepwise lengthening. This has enabled an increase in the diameter of the pulley to 4 times its original size. A prospective study was performed comprising 10 trigger finger releases with stepwise lengthening of the A1 pulley. In all patients, there were no complications, and good hand function was achieved with no recurrence of triggering at 6 weeks of follow-up. This technique can thus safely achieve trigger release without sacrifice of the function of the A1 pulley. PMID:24229038

  2. Assessment of the Distal Extent of the A1 Pulley Release: A New Technique

    PubMed Central

    Hazani, Ron; Engineer, Nitin J.; Zeineh, Linda L.; Wilhelmi, Bradon J.

    2008-01-01

    Objective: Sharp division of the A1 pulley is a time-honored technique for the treatment of flexor tendon entrapment; however, this procedure is not without complications. The anatomy of the A1 pulley system has been carefully investigated. Knowledge of superficial anatomic landmarks can assist with demarcating the distal edge of the A1 pulley and prevent damage to the critical A2 pulley. Methods: Nine fresh cadaveric hands were dissected with the aid of loupe magnification. On the basis of known anatomic landmarks of the proximal portion of the cruciate (C0) pulley, percutaneous placement of a 25-gauge needle 5 mm proximal to the palmar digital crease marked the distal extent of the trigger finger release. Sharp division of the A1 pulley was performed with a scalpel until the needle was encountered, thus completing the release. Results: A complete release of the pulley was achieved in all specimens with preservation of the A2 pulley. No digital nerve or artery injuries were noted with open inspection of the flexor sheath. Conclusion: Percutaneous marking of the distal extent of the A1 pulley is a safe and reliable method that not only ensures complete release of the A1 pulley but also preserves the A2 pulley. The placement of a small gauge needle adds no morbidity to this minimally invasive technique. PMID:18806871

  3. Percutaneous release of the A1 pulley using a modified Kirschner wire: a cadaveric study.

    PubMed

    Saengnipanthkul, Sukit; Sae-Jung, Surachai; Sumananont, Chat

    2014-08-01

    PURPOSE. To evaluate the outcome of percutaneous release of the A1 pulley in 40 cadaveric fingers using a modified Kirschner wire. METHODS. A 2.5-mm-diameter Kirschner wire measuring >12 cm in length was used. One end of the wire was sharpened into a 'J' shape using a grinder. The J-shaped tip featured a blunt, elongated lower tip, a sharp J-shaped curve, and a blunt upper tip. Completeness of A1 pulley release and injuries to the A2 pulley, flexor tendon, and neurovascular structures were evaluated in 40 cadaveric fingers. RESULTS. Complete release of the A1 pulley was achieved in 8 index, 7 middle, 8 ring, and 8 little fingers, whereas incomplete release of the distal part was noted in 2 index, 2 middle, 2 ring, and one little fingers; release was missed in one middle and one little fingers. Injury to the A2 pulley was noted in 2 index fingers; the injury was minimal and limited to the proximal 2 mm of the A2 pulley. There was no flexor tendon or digital nerve injury in any finger. CONCLUSION. Percutaneous release of the A1 pulley using a modified Kirschner wire achieved complete release in 78% of cadaveric fingers, which is comparable to that using a specially manufactured push knife.

  4. Comparative clinical study of ultrasound-guided A1 pulley release vs open surgical intervention in the treatment of trigger finger

    PubMed Central

    Nikolaou, Vasileios S; Malahias, Michael-Alexander; Kaseta, Maria-Kyriaki; Sourlas, Ioannis; Babis, George C

    2017-01-01

    AIM To investigate the effectiveness of ultrasound-guided release of the first annular pulley and compare results with the conventional open operative technique. METHODS In this prospective randomized, single-center, clinical study, 32 patients with trigger finger or trigger thumb, grade II-IV according to Green classification system, were recruited. Two groups were formed; Group A (16 patients) was treated with an ultrasound-guided percutaneous release of the affected A1 pulley under local anesthesia. Group B (16 patients) underwent an open surgical release of the A1 pulley, through a 10-15 mm incision. Patients were assessed pre- and postoperatively (follow-up: 2, 4 and 12 wk) by physicians blinded to the procedures. Treatment of triggering (primary variable of interest) was expressed as the “success rate” per digit. The time for taking postoperative pain killers, range of motion recovery, QuickDASH test scores (Greek version), return to normal activities (including work), complications and cosmetic results were assessed. RESULTS The success rate in group A was 93.75% (15/16) and in group B 100% (16/16). Mean times in group A patients were 3.5 d for taking pain killers, 4.1 d for returning to normal activities, and 7.2 and 3.9 d for complete extension and flexion recovery, respectively. Mean QuickDASH scores in group A were 45.5 preoperatively and, 7.5, 0.5 and 0 after 2, 4, and 12 wk postoperatively. Mean times in group B patients were 2.9 d for taking pain killers, 17.8 d for returning to normal activities, and 5.6 and 3 d for complete extension and flexion recovery. Mean QuickDASH scores in group B were 43.2 preoperatively and, 8.2, 1.3 and 0 after 2, 4, and 12 wk postoperatively. The cosmetic results found excellent or good in 87.5% (14/16) of group A patients, while in 56.25% (9/16) of group B patients were evaluated as fair or poor. CONCLUSION Treatment of the trigger finger using ultrasonography resulted in fewer absence of work days, and better

  5. Kinematical and functional improvements of trigger digits after sonographically assisted percutaneous release of the A1 pulley.

    PubMed

    Kuo, Li-Chieh; Su, Fong-Chin; Tung, Wen-Lin; Lai, Kuan-Yin; Jou, I-Ming

    2009-07-01

    We present evidence of kinematic and functional improvements of the trigger digit after sonographically assisted percutaneous release using quantitative motion analyses and functional assessments, respectively. Twenty-two patients with idiopathic trigger digits, who received the surgery, were recruited. A motion tracking system was used to measure the assigned kinematics parameters at the presurgical visit and at 1, 4, and 12 weeks after surgery. The hand strength and functional outcome were also obtained using dynamometer and self-report questionnaire assessments. The hand strength, maximal workspace, and joint range of motion of the involved digit were significantly smaller than that of the intact finger on the contralateral hand before surgery. The triggering phenomenon of the involved digit was significantly higher than that of the corresponding finger in the intact hand using a subscribed angular acceleration factor. The repeated measures showed that the workspace, joint range of motion, hand strength, and triggering effect of the involved hand significantly improved in follow-up examinations after the surgical intervention. Painful movement or insufficient tendon excursion of the trigger digit can cause loss of movement and strength, thus interfering with functional performance. After the disappearance of the pain and triggering by sonographically assisted percutaneous release, improvements in kinematics and function were objectively quantified in this study.

  6. Comparison of three different incision techniques in A1 pulley release on scar tissue formation and postoperative rehabilitation.

    PubMed

    Kloeters, Oliver; Ulrich, Dietmar J O; Bloemsma, Gijs; van Houdt, Claire I A

    2016-05-01

    The optimal surgical approach for trigger finger release remains controversial in hindsight of postoperative rehabilitation as well as scar tissue formation. In this study, we comparatively evaluated the outcome of three different types of skin incision by employing the "Disability of the Arm Shoulder and Hand Score" (DASH) and by quantitative ultrasound measurements of scar tissue volume. Thirty patients (32 triggerfingers) were enrolled in this study and randomly assigned to one of three groups: incision placed (1) transversal in distal palmar crease, (2) transversal and 2 mm distal from distal palmar crease, (3) longitudinally over MCP joint without crossing the distal palmar crease. Patients characteristics were noted and DASH scores were retrieved at four time points, (1) preoperatively (baseline), (2) 1 month, (3) 3 months, (4) 12 months postoperatively. Scar volume formation was assessed by ultrasound at 3 months postoperatively in 28 patients. All groups showed a significant reduction in DASH values at 3 and 12 months postoperatively when compared to their own baseline levels. Group 3 showed the fastest and most pronounced reduction in DASH values at 1 month. Scar tissue formation was almost 57 % increased in group 1 vs group 2 and 3, however, not significant. There is no clear benefit of one incision technique over another. However, based on scar volume parameters, the significant faster recovery in the first month and the surgical ease of exposure and wound closure inclines us to favor the longitudinal incision (group 3) in future patients.

  7. Isolated A1 Pulley Rupture of Left Fourth Finger in Kendo Players: Two Case Reports

    PubMed Central

    Lee, Jin Hyung; Joo, Seung Ho

    2015-01-01

    Annular pulley injury of fingers is usually observed in rock climbers who support their entire body weight with flexed fingers during climbing. But these lesions can also follow trivial trauma, such as lifting heavy objects with the fingertips, or during sports and recreational activities. The A2 and A4 pulleys are most usually involved and reported most frequently. However, traumatic A1 pulley rupture has not been reported yet, to the best of our knowledge. Kendo is a very vigorous martial art with frequent physical contact. Therefore, we reported two cases of repetitive microtraumatic left fourth finger A1 pulley rupture in Kendo players with results from physical examination and imaging studies, such as ultrasonography and magnetic resonance imaging, together with related literature. PMID:26605184

  8. Ultrasound-guided percutaneous release of the annular pulley in trigger digit.

    PubMed

    Rajeswaran, Gajan; Lee, Justin C; Eckersley, Rupert; Katsarma, Effie; Healy, Jeremiah C

    2009-09-01

    The purpose of this study was to describe and evaluate a new technique for ultrasound-guided percutaneous release of the annular pulley in trigger digit using a modified hypodermic needle. A total of 35 ultrasound-guided percutaneous releases were performed on 25 patients diagnosed and referred by hand surgeons in our institution over 16 months from October 2006. Inclusion criteria were as follows: adulthood, triggering present for at least 4 months, failure to respond to conservative management or steroid injections, no previous history of pulley release in the affected digit. Under ultrasound guidance, the affected pulley was released using a standard 19-gauge hypodermic needle bent at two points as the cutting device. Follow-up took place at 12 weeks and 6 months with improvement in triggering and clinically graded pain. At follow-up, no complications had occurred and all patients demonstrated improvement in their triggering, with complete resolution in 32 digits (91%), good improvement in 2 digits (6%) and some improvement in 1 digit (3%). This new technique uses a widely available and safe cutting device and is safe and can be used to provide definitive management for trigger finger, allowing the procedure to be performed in a variety of clinical settings.

  9. Sonographic appearance of the flexor tendon, volar plate, and A1 pulley with respect to the severity of trigger finger.

    PubMed

    Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo; Takeda, Mitsuhiro

    2012-10-01

    To evaluate trigger digits with sonography to determine morphological changes in the A1 pulley, flexor tendon, and volar plate in relation to the severity of triggering. We evaluated 67 trigger digits and graded them into 1 of 4 groups. We compared the groups according to severity and to contralateral fingers, which served as controls. The thickness of the flexor tendons under the A1 pulley was proportional to the severity of triggering. The anteroposterior thickness of the flexor tendon increased significantly among the grades exhibiting triggering regardless of the affected digit. However, in digits other than the thumb, tendon thickness increased even in the absence of active triggering. Thickening tended to be greater with finger flexion. The A1 pulley exhibited the greatest thickness and the volar plate exhibited significant thickening in the group that exhibited continuous triggering that was easily reduced with active extension (grade III). The flexor tendon thickened significantly before patients experienced triggering except in the thumb. In the thumb, the flexor tendon and A1 pulley thickened significantly only after patients exhibited triggering. Thickening of the volar plate appears to have an important role in continuous triggering. Although most clinicians can easily determine the severity of a trigger digit by clinical examination, ultrasound might be helpful for objectively understanding the severity and response to treatment, by examining the thickness of the flexor tendon and A1 pulley. In particular, sonographic measurement of the A1 pulley might be useful in judging the progression of trigger finger severity. In cases where a Doppler signal is detected inside the A1 pulley, more conservative therapies might be worth considering before surgery. Diagnostic ΙΙΙ. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  10. Volar A1 pulley approach for fixation of avulsion fractures of the base of the proximal phalanx.

    PubMed

    Kuhn, K M; Dao, K D; Shin, A Y

    2001-07-01

    Avulsion fractures of the base of the proximal phalanx associated with collateral ligament instability, excluding the thumb, are relatively rare. While the indications for surgical intervention vary, dorsal approaches have been advocated despite the volar location of the fracture fragment and orientation of the collateral ligaments. Ten patients with 11 avulsion fractures at the base of the proximal phalanx associated with collateral ligament instability were treated with open reduction and internal fixation using a volar A1 pulley approach. Anatomic restoration of the articular surface and collateral ligament stability were obtained in all patients. All fractures healed between 5 and 9 weeks (average, 6 weeks). After an average 19.4-month follow-up period all patients had full range of motion of the metacarpophalangeal joint, collateral ligament stability, and grip strength of at least 90% of the uninjured hand. No perioperative complications occurred. The average DASH score at last follow-up examination was 1.8 (range, 0-6). All patients were satisfied with the outcome of surgery. The volar A1 pulley approach is a direct and effective approach for reduction and fixation of avulsion fractures of the base of the proximal phalanx associated with collateral ligament instability.

  11. [Flexor tendon pulley system: anatomy, pathology, treatment].

    PubMed

    Moutet, F

    2003-02-01

    Flexor tendon pulley has been very early noticed and described. Terminology usually accepted recognizes 6 arcifom pulleys (A0 to A5) and 3 cruciform pulleys (C1 to C3). Anatomy and physiology of this flexor tendon gliding and reflection system at the level of the digital sheet are exposed. The integrity necessity of this system became obvious regarding the flexor tendons repair. Four main pathologies may be concerned: the trigger finger congenital or progressive, due to a chondroid metaplasia of the A1 pulley; tenosynovial ganglions arising at the weak point between A1 and A2 pulley; lesions of the flexor tendon sheet during traumatic lacerations or surgical repairs; quite experimental lesions creating isolated ruptures of one or several pulleys which occur during sport practice, especially high level rock climbing. The repair techniques are exposed to allow to graduate and hierarchy the reparation technique regarding the pathology. A2 and A4 repair is always indicated. The best reconstruction material is an extensor retinaculum graft. But its poor surface available often draws to use conventional palmaris longus free graft.

  12. Lesions of the biceps pulley.

    PubMed

    Braun, Sepp; Horan, Marilee P; Elser, Florian; Millett, Peter J

    2011-04-01

    Lesions of the biceps pulley and instability of the long head of the biceps tendon are common diagnoses in patients with anterior shoulder pain. To analyze the pathoanatomy of the biceps reflection pulley ("pulley") in consecutive patients undergoing shoulder arthroscopy. Cohort study (prevalence); Level of evidence, 2. Prospective data were collected on 229 shoulders in consecutive patients (155 male,74 female) who underwent shoulder arthroscopy (121 rotator cuff pathology, 50 instability, 43 osteoarthritis, 15 miscellaneous). The average age was 48.5 years (range, 18-76 years). Sixty-eight shoulders had underwent a previous surgery. The long head of the biceps tendon was absent in 21 shoulders (9.2%); 1 was excluded for incomplete data. In 207 shoulders, the mean width of the long head of the biceps tendon was 6.0 mm (range, 3-10 mm), and the pulley complex, 7.2 mm (range, 4-15 mm). Sixty-seven patients (32.4%) had a pulley tear: 48 shoulders had anteromedial pulley tears, 32 posterolateral, with 13 combined anteromedial-posterolateral lesions. Patients with pulley tears were significantly older than those without (57 vs 44 years, P < .001). For anteromedial pulley tears, the mean width of the long head of the biceps tendon was significantly larger in the torn group (6.4 vs 5.8 mm, P = .012). The anteromedial or posterolateral pulley tears were significantly associated with subluxation or dislocation of the long head of the biceps tendon (P = .001), with a pulley torn in all 27 cases of biceps dislocation. In 173 shoulders with a centered long head of the biceps tendon, the pulley was torn in 36 (23 anteromedial, 18 posterolateral [with 5 being combined]). Pulley tears and rotator cuff injury showed a significant association (P < .001). Superior labral anterior posterior lesions were significantly associated with anteromedial (P < .008) and posterolateral pulley tears (P < .021). Pulley lesions are fairly common in patients undergoing arthroscopic surgery and

  13. Identification of the Position and Thickness of the First Annular Pulley in Sonographic Images.

    PubMed

    Yang, Tai-Hua; Lin, Yi-Hsun; Chuang, Bo-I; Chen, Hsin-Chen; Lin, Wei-Jr; Yang, Dee-Shan; Wang, Shyh-Hau; Sun, Yung-Nien; Jou, I-Ming; Kuo, Li-Chieh; Su, Fong-Chin

    2016-05-01

    The purpose was to identify the A1 pulley's exact location and thickness by comparing measurements from a clinical high-frequency ultrasound scanner system (CHUS), a customized high-frequency ultrasound imaging research system (HURS) and a digital caliper. Ten cadaveric hands were used. We explored the pulley by layers, inserted guide pins and scanned it with the CHUS. After identifying the pulley, we measured each long finger's thickness using the CHUS and excised the pulley to measure its thickness with a digital caliper and the HURS. The thin hypo-echoic layer was revealed to be the synovial fluid space, and the pulley appears hyper-echoic regardless of scan direction. We also defined the pulley's boundaries. Moreover, the CHUS provided a significantly lower measurement of the pulley's thickness than the digital caliper and HURS. Likewise, based on the digital caliper's measurement, the HURS had significantly lower mean absolute and relative errors than the CHUS.

  14. Development of a synthetic replacement for the flexor tendon pulleys--an experimental study.

    PubMed

    Peterson, W W; Manske, P R; Lesker, P A; Kain, C C; Schaefer, R K

    1986-05-01

    A method was developed to reconstruct the fibro-osseous pulleys with Nitex, a synthetic material. Nitex is a closely woven fabric constructed from monofilament nylon fibers. Six adult monkeys (24 digits) had excision of the A1 and A2 pulleys; this was followed by reconstruction of the A2 pulley with the Nitex synthetic material. The animals were killed, two at a time, at 4, 8, and 12 weeks to evaluate the effectiveness of the Nitex pulleys. Flexor tendon function was assessed by biomechanical methods with a tensile testing machine to measure the tendon excursion and the work of flexion (the area under the force-excursion curve) necessary to fully flex each digit; these parameters revealed that the Nitex pulleys were capable of preventing tendon bow-stringing and did not significantly impair tendon gliding. The breaking strength of the Nitex pulleys was comparable to that of normal A2 pulleys (for monkeys weighing less than 10 kg) and it was sufficient to allow immediate mobilization of the digits postoperatively without fear of pulley rupture. Histologic examination showed minimal foreign body reaction around the Nitex, and the gliding surface of a Nitex pulley was found to be covered with a smooth layer of fibrous tissue with minimal adhesions to the underlying flexor tendon. The synthetic Nitex pulley appears to have the potential to function as an effective fibro-osseous pulley replacement.

  15. Flexor Tendon Pulley Injuries in Rock Climbers.

    PubMed

    King, Elizabeth A; Lien, John R

    2017-02-01

    Closed pulley ruptures are rare in the general population but occur more frequently in rock climbers due to biomechanical demands on the hand. Injuries present with pain and swelling over the affected pulley, and patients may feel or hear a pop at the time of injury. Sequential pulley ruptures are required for clinical bowstringing of the flexor tendons. Ultrasound confirms diagnosis of pulley rupture and evaluates degree of displacement of the flexor tendons. Isolated pulley ruptures frequently are treated conservatively with early functional rehabilitation. Sequential pulley ruptures require surgical reconstruction. Most climbers are able to return to their previous activity level.

  16. Quantitative Assessment of First Annular Pulley and Adjacent Tissues Using High-Frequency Ultrasound

    PubMed Central

    Lin, Yi-Hsun; Yang, Tai-Hua; Wang, Shyh-Hau; Su, Fong-Chin

    2017-01-01

    Due to a lack of appropriate image resolution, most ultrasound scanners are unable to sensitively discern the pulley tissues. To extensively investigate the properties of the A1 pulley system and the surrounding tissues for assessing trigger finger, a 30 MHz ultrasound system was implemented to perform in vitro experiments using the hypodermis, A1 pulley, and superficial digital flexor tendon (SDFT) dissected from cadavers. Ultrasound signals were acquired from both the transverse and sagittal planes of each tissue sample. The quantitative ultrasonic parameters, including sound speed, attenuation coefficient, integrated backscatter (IB) and Nakagami parameter (m), were subsequently estimated to characterize the tissue properties. The results demonstrated that the acquired ultrasound images have high resolution and are able to sufficiently differentiate the variations of tissue textures. Moreover, the attenuation slope of the hypodermis is larger than those of the A1 pulley and SDFT. The IB of A1 pulley is about the same as that of the hypodermis, and is very different from SDFT. The m parameter of the A1 pulley is also very different from those of hypodermis and SDFT. This study demonstrated that high-frequency ultrasound images in conjunction with ultrasonic parameters are capable of characterizing the A1 pulley system and surrounding tissues. PMID:28067854

  17. Efficiency of the flexor tendon pulley system in human cadaver hands.

    PubMed

    Rispler, D; Greenwald, D; Shumway, S; Allan, C; Mass, D

    1996-05-01

    The efficiency of the flexor tendon system was examined in a human cadaver model. Pulleys were randomly sectioned, and the results were evaluated on the basis of the tendon excursion, force generated at the fingertip, and the work (force multiplied by distance) involved, as compared to the intact pulley system. When a single minor pulley (A1 or A5) was cut, there was no statistical difference in work efficiency or excursion efficiency from controls. Cutting all minor pulleys (A1, A3, A5) lead to a significant loss in excursion efficiency. The intact three pulley systems of A2, A3, and A4 were near normal and statistically better than A2 and A4 together for work efficiency. Cutting one of the major pulleys (A2, A4) resulted in significant changes in efficiency, but what was unexpected was to find an 85% loss of both work and excursion efficiency for the loss of A4 but only an excursion difference of 94% for the loss of A2. Our findings demonstrated that in this model, with the influence of the skin removed, A4 absence produced the largest biomechanically measured efficiency changes and that a combination of A2, A3, and A4 was necessary to preserve both work and excursion efficiency.

  18. Materials science: Pulley protection in batteries

    NASA Astrophysics Data System (ADS)

    McDowell, Matthew T.

    2017-09-01

    High-energy battery electrodes can break apart during operation. Conventional rope-and-pulley systems have inspired the development of a polymer that holds electrodes together at the molecular scale, enabling durable batteries to be made.

  19. A study of 60 patients with percutaneous trigger finger releases: clinical and ultrasonographic findings.

    PubMed

    Gulabi, D; Cecen, G S; Bekler, H I; Saglam, F; Tanju, N

    2014-09-01

    We present the clinical results and ultrasonographic findings of 61 trigger digits treated with percutaneous A1 pulley release. An endoscopic carpal tunnel knife was used for the release in the outpatient department. The mean follow-up period was 3.5 months. A total of 55 digits (90%) had complete relief of their triggering postoperatively. Six digits (10%) had Grade 2 triggering clinically in the early postoperative period.The complications included six cases of insufficient release (10%), scar sensitivity in one patient, short-term hypoaesthesia in three digits (5%), and flexor tendon laceration noted on postoperative ultrasonography in eight digits (13%). No neurovascular damage was noted on the postoperative ultrasonography. Ultrasonograpy provides information about tendon laceration and changes in thickness of the pulleys and confirm A1 pulley release after surgery, but it does not alter clinical decision-making. We believe that pre- and postoperative ultrasonograpy does not need to be included as a routine examination.

  20. The biomechanical significance of pulley on binocular vision.

    PubMed

    Guo, Hongmei; Gao, Zhipeng; Chen, Weiyi

    2016-12-28

    Pulleys have been reported as the functional origins of the rectus extraocular muscles (EOMs). However, biomechanical significance of pulleys on binocular vision has not been reported. Three eye movement models, i.e., non-pulley model, passive-pulley model, and active-pulley model, are used to simulate the horizontal movement of the eyes from the primary position to the left direction in the range of 1°-30°. The resultant forces of six EOMs along both orthogonal directions (i.e., the x-axis and y-axis defined in this paper) in the horizontal plane are calculated using the three models. The resultant force along the y-axis of the left eye for non-pulley model are significantly larger than that of the other two pulley models. The difference of the force, between the left eye and the right eye in non-pulley model, is larger than those in the other two pulley models along x-axis and y-axis. The pulley models present more biomechanical advantage on the horizontally binocular vision than the non-pulley model. Combining with the previous imaging evidences of pulleys, the results show that pulley model coincides well with the real physiological conditions.

  1. A biomechanical study of the flexor digitorum superficialis: effects of digital pulley excision and loss of the flexor digitorum profundus.

    PubMed

    Hamman, J; Ali, A; Phillips, C; Cunningham, B; Mass, D P

    1997-03-01

    Many reports have been devoted to characterizing the significance of the pulleys for the flexor digitorum profundus (FDP). However, no comparable work has been published on the flexor digitorum superficialis (FDS). This study characterized the FDS in a human cadaver model. Eleven fresh-frozen cadaver hands were used. By using a tensiometer, data were gathered for tendon excursion, tendon load, and work of flexion. Changes in efficiency were caused by excision of annular pulleys A1, A2, A3, and the palmar aponeurotic pulley. We also measured the effect of FDP excision on FDS efficiency. Sectioning of the A2 and A3 pulleys together caused statistically significant losses of efficiency in all three parameters (work, load, and excursion). When the FDP was removed from a finger with an intact pulley system, losses in both work and excursion efficiencies were significant. Removing the FDP while cutting different pulleys caused significant decrease in FDS excursion efficiency. We conclude that A2 and A3 are the most important pulleys for maintaining normal FDS function, and that the presence of the FDP in the digital sheath is essential for optimal FDS excursion efficiency.

  2. 30 CFR 75.1728 - Power-driven pulleys.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Power-driven pulleys. 75.1728 Section 75.1728... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1728 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with...

  3. 30 CFR 77.407 - Power-driven pulleys.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Power-driven pulleys. 77.407 Section 77.407... for Mechanical Equipment § 77.407 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with the hands except on slow...

  4. 30 CFR 77.407 - Power-driven pulleys.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Power-driven pulleys. 77.407 Section 77.407... for Mechanical Equipment § 77.407 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with the hands except on slow...

  5. 30 CFR 75.1728 - Power-driven pulleys.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Power-driven pulleys. 75.1728 Section 75.1728... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1728 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with...

  6. 30 CFR 75.1728 - Power-driven pulleys.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Power-driven pulleys. 75.1728 Section 75.1728... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1728 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with...

  7. 30 CFR 75.1728 - Power-driven pulleys.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Power-driven pulleys. 75.1728 Section 75.1728... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1728 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with...

  8. 30 CFR 77.407 - Power-driven pulleys.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Power-driven pulleys. 77.407 Section 77.407... for Mechanical Equipment § 77.407 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with the hands except on slow...

  9. 30 CFR 77.407 - Power-driven pulleys.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Power-driven pulleys. 77.407 Section 77.407... for Mechanical Equipment § 77.407 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with the hands except on slow...

  10. 30 CFR 75.1728 - Power-driven pulleys.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Power-driven pulleys. 75.1728 Section 75.1728... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1728 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with...

  11. 30 CFR 77.407 - Power-driven pulleys.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Power-driven pulleys. 77.407 Section 77.407... for Mechanical Equipment § 77.407 Power-driven pulleys. (a) Belts, chains, and ropes shall not be guided onto power-driven moving pulleys, sprockets, or drums with the hands except on slow...

  12. [Flexor pulleys of the fingers. Anatomy, biomechanics, reconstruction].

    PubMed

    Hahn, P; Lanz, U

    1996-09-01

    Primary or secondary flexor tendon surgery occasionally leads to damaged flexor pulleys. Insufficient pulley reconstruction causes loss of finger function by bow stringing of the flexor tendon. This paper reviews the anatomy and biomechanics of the flexor pulley system. Different techniques of reconstruction are discussed.

  13. 30 CFR 57.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Manual cleaning of conveyor pulleys. 57.14202... and Equipment Safety Practices and Operational Procedures § 57.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  14. 30 CFR 56.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Manual cleaning of conveyor pulleys. 56.14202... Equipment Safety Practices and Operational Procedures § 56.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  15. 30 CFR 57.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Manual cleaning of conveyor pulleys. 57.14202... and Equipment Safety Practices and Operational Procedures § 57.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  16. 30 CFR 57.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Manual cleaning of conveyor pulleys. 57.14202... and Equipment Safety Practices and Operational Procedures § 57.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  17. 30 CFR 56.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Manual cleaning of conveyor pulleys. 56.14202... Equipment Safety Practices and Operational Procedures § 56.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  18. 30 CFR 56.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Manual cleaning of conveyor pulleys. 56.14202... Equipment Safety Practices and Operational Procedures § 56.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  19. 30 CFR 56.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Manual cleaning of conveyor pulleys. 56.14202... Equipment Safety Practices and Operational Procedures § 56.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  20. 30 CFR 57.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Manual cleaning of conveyor pulleys. 57.14202... and Equipment Safety Practices and Operational Procedures § 57.14202 Manual cleaning of conveyor pulleys. Pulleys of conveyors shall not be cleaned manually while the conveyor is in motion....

  1. Spinning a pulley with a vibrating cord: A marvel

    NASA Astrophysics Data System (ADS)

    Vermillion, R. E.; Simpson, H. M.

    1989-06-01

    A pulley can be caused to rotate by creating longitudinal vibrations in a cord that passes over the pulley. For small amplitudes and high frequencies, the motion of the cord is too small to notice and the pulley seems to be spinning with no cause, creating a striking effect. Pulley rotations were observed for a variety of pulleys and cords; nearly any such system will work. The speed and direction of the rotation depends on the various physical parameters of the system: vibration frequency and amplitude, cord tension, and the radius and moment of inertia of the pulley. An investigation is reported of pulley response versus cord frequency and amplitude for a typical system.

  2. Sonographic analyses of pulley and flexor tendon in idiopathic trigger finger with interphalangeal joint contracture.

    PubMed

    Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo; Takeda, Mitsuhiro

    2014-06-01

    This study investigated the sonographic appearance of the pulley and flexor tendon in idiopathic trigger finger in correlation with the contracture of the interphalangeal (IP) joint in the thumb or proximal IP (PIP) joint in the other digits. Sonographic measurements using axial images were performed in 177 affected digits including 17 thumbs and 34 other digits judged to have IP or PIP joint contracture and 77 contralateral control digits. The A1 pulley of the contracture group was significantly thicker than that of the non-contracture group in all digits, whereas the flexor tendon was thicker only in digits other than the thumb. In the analysis using calculated cut-off values, A1 pulley thickening in the thumb and A1 pulley and flexor tendon thickening in the other digits showed statistically significant correlations with IP or PIP joint contracture. This study sonographically confirmed previous reports showing that enlargement of the flexor tendons contribute to the pathogenesis of PIP joint contracture. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  3. Can a String's Tension Exert a Torque on a Pulley?

    ERIC Educational Resources Information Center

    Krause, Dennis E.; Sun, Yifei

    2011-01-01

    A typical textbook problem in rotational dynamics involves calculating the angular acceleration of a massive pulley due to a string, such as in the example shown in Fig. 1. The string is assumed to be massless and to move without slipping over the pulley, which is mounted on a frictionless axle. If T[subscript L] and T[subscript R] are the…

  4. Can a String's Tension Exert a Torque on a Pulley?

    ERIC Educational Resources Information Center

    Krause, Dennis E.; Sun, Yifei

    2011-01-01

    A typical textbook problem in rotational dynamics involves calculating the angular acceleration of a massive pulley due to a string, such as in the example shown in Fig. 1. The string is assumed to be massless and to move without slipping over the pulley, which is mounted on a frictionless axle. If T[subscript L] and T[subscript R] are the…

  5. Can a String's Tension Exert a Torque on a Pulley?

    NASA Astrophysics Data System (ADS)

    Krause, Dennis E.; Sun, Yifei

    2011-04-01

    A typical textbook problem in rotational dynamics involves calculating the angular acceleration of a massive pulley due to a string, such as in the example shown in Fig. 1. The string is assumed to be massless and to move without slipping over the pulley, which is mounted on a frictionless axle. If TL and TR are the tensions pulling at the left and right edges of the pulley (see Fig. 1), respectively, the net torque on the pulley is then τnet = (TL - TR)R, where R is the radius of the pulley. (It is assumed that positive torque corresponds to the counterclockwise direction.) While this analysis, which is typical of what is found in many introductory physics texts, is correct, it should raise several questions in the mind of a student. First, since most texts argue that the tension everywhere in a massless string is constant,2 why is TL ≠ TR? Second, since tension is an internal force (except at the ends of the string, which are obviously not tied to the pulley),3 how can tension exert a force and torque on a pulley? In this paper, we will address these questions, which are overlooked in most textbook treatments of this problem whose approach appears inconsistent with the concepts presented elsewhere in the text.

  6. Compact pulley-type microring resonator with high quality factor

    NASA Astrophysics Data System (ADS)

    Cai, Dong-Po; Lu, Jyun-Hong; Chen, Chii-Chang; Lee, Chien-Chieh; Lin, Chu-En; Yen, Ta-Jen

    2014-11-01

    A pulley-type microring resonator with ultra-small dimensions and ultra-high quality factor on a silicon-on-insulator wafer is fabricated and characterized. Simulation results show that the bending loss of the pulley-type microring resonator can be diminished by wrapping the curved waveguide around the microring, and that the energy loss from the output port can be decreased by tuning the width of the bus waveguide to achieve destructive interference. A quality factor of 1.73 × 105 is obtained in this experiment. The compact size of the pulley-type microring resonator with low bending loss is suitable for an integrated optical circuit.

  7. 25. VIEW FOURTH FLOOR, ELEVATOR PULLEY TRANSPORT SYSTEM, LOOKING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. VIEW FOURTH FLOOR, ELEVATOR PULLEY TRANSPORT SYSTEM, LOOKING AT TOP MAIN WOOD AND STEEL BEAM SUPPORT SYSTEM, NORTHWEST - Bates Manufacturing Company, Storehouse, Northeast corner of Chestnut Street & Hines Alley, Lewiston, Androscoggin County, ME

  8. 8. DETAIL VIEW NORTHWEST OF SOUTH TURBINE SHAFT AND PULLEY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. DETAIL VIEW NORTHWEST OF SOUTH TURBINE SHAFT AND PULLEY WHEEL - Willimantic Linen Company, Mill No. 2, South Main Street opposite Durham Street, North bank Willimantic River, Windham, Windham County, CT

  9. 8. Elevator no. 2: Track shed, showing cable and pulleys ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Elevator no. 2: Track shed, showing cable and pulleys for moving train cars, facing east - Washburn Crosby Company Elevators No. 2 & 3, 900 & 1000 Second Avenue, South, Minneapolis, Hennepin County, MN

  10. The flexor tendon pulley system and rock climbing.

    PubMed

    Crowley, Timothy P

    2012-06-01

    Rock climbing has increased in popularity over the past two decades. Closed traumatic rupture of the finger flexor tendon pulleys is rare among the general population but is seen much more commonly in rock climbers. This article reviews the anatomy and biomechanics of the finger flexor tendon pulleys, how they may be injured in rock climbing and how these injuries are best diagnosed and managed.

  11. Innervation of extraocular pulley smooth muscle in monkeys and humans.

    PubMed

    Demer, J L; Poukens, V; Miller, J M; Micevych, P

    1997-08-01

    Soft pulleys stabilize paths and determine pulling directions of the extraocular muscles (EOMs). This study was conducted to characterize innervation of smooth muscles (SMs) supporting these pulleys. Cadaveric human and monkey orbits were step and serially sectioned for histochemical and immunohistochemical staining. Before perfusion, the superior cervical ganglia of one monkey had been injected with the anterograde tracer Phaseolus vulgaris leukoagglutinin (PHA-L). Immunoperoxidase staining to human SM alpha-actin confirmed pulley SM. Monoclonal and polyclonal antibodies were used to demonstrate PHA-L, tyrosine hydroxylase, dopamine beta-hydroxylase, phenylethanolamine-N-methyltransferase, neuronal nitric oxide synthase (NOS), and synaptophysin. The NADPH-diaphorase reaction was also used as a marker for NOS and the acetylcholinesterase (AChE) reaction for acetylcholine. Pulleys, consisting of collagen and elastin sleeves supported by connective tissue containing SM, were observed around rectus muscles of humans and monkeys. The human and monkey SM was richly innervated. Axons terminating in motor end plates within SM bundles were immunoreactive to PHA-L, tyrosine hydroxylase, and dopamine beta-hydroxylase, but not phenylethanolamine-N-methyltransferase, indicating innervation of pulley SM from the superior cervical ganglion by projections using norepinephrine. Smaller axons and motor end plates were also demonstrated in SM, using NADPH-diaphorase and NOS immunoreactivity, indicating nitroxidergic innervation, and using AchE, indicating cholinergic parasympathetic innervation. The pterygopalatine and, to a lesser extent, the ciliary ganglia, but not the Edinger-Westphal nucleus, contained cells immunoreactive to NOS, suggesting that nitroxidergic innervation to pulley SM is mainly from the pterygopalatine ganglion. The SM suspensions of human and monkey EOM pulleys are similar and receive rich innervation involving multiple neurotransmitters. These complex

  12. A biomechanical study of the finger pulley system during repair.

    PubMed

    Amirouche, F; Gonzalez, M; Koldoff, J; Tioco, J; Ham, K

    2002-01-01

    This paper addresses the mechanics of the finger/pulley system when subjected to various excisions and repairs. Several cadaver hands were used to study the finger/pulley's function, finger joint dynamics, and the relationship between tendon excursion and finger joint angles of rotation. By using a method of continuous and simultaneous data acquisition of the entire finger joint's motion, a more detailed analysis was achieved. Our experimental investigation is based on the use of four micro-potentiometers inserted at the finger's joints and a pulley system to simulate tendon excursion. Using this procedure, a detailed kinematic analysis of the entire finger was performed. This included analysis of the intact hand, various pulley excisions, and reconstruction. In addition to introducing a new method of acquisition, a mathematical model was developed for the inverse dynamic analysis of the finger pulley system. From this model, the torques required at the joints for the motion were computed. The results provided new insight into possible ways of characterizing kinematic changes resulting from pulley damage and repair.

  13. Diagnosis of Complex Pulley Ruptures Using Ultrasound in Cadaver Models.

    PubMed

    Schöffl, Isabelle; Hugel, Arnica; Schöffl, Volker; Rascher, Wolfgang; Jüngert, Jörg

    2017-03-01

    Pulley ruptures are common in climbing athletes. The purposes of this study were to determine the specific positioning of each pulley with regards to the joint, and to evaluate the ultrasound diagnostics of various pulley rupture combinations. For this, 34 cadaver fingers were analyzed via ultrasound, the results of which were compared to anatomic measurements. Different pulley ruptures were then simulated and evaluated using ultrasound in standardized dynamic forced flexion. Visualization of the A2 and A4 pulleys was achieved 100% of the time, while the A3 pulley was visible in 74% of cases. Similarly, injuries to the A2 and A4 pulleys were readily observable, while A3 pulley injuries were more challenging to identify (sensitivity of 0.2 for singular A3 pulley, 0.5 for A2/A4 pulley and 0.33 for A3/A4 pulley ruptures). Receiver operating characteristic analysis was used to evaluate the optimal tendon-bone distance for pulley rupture diagnosis, a threshold which was determined to be 1.9 mm for A2 pulley ruptures and 1.85 for A4 pulley ruptures. This study was the first to carry out a cadaver ultrasound examination of a wide variety of pulley ruptures. Ultrasound is a highly accurate tool for visualizing the A2 and A4 pulleys in a cadaver model. This method of pathology diagnosis was determined to be suitable for injuries to the A2 and A4 pulleys, but inadequate for A3 pulley injuries. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  14. Development of a synthetic replacement for flexor tendon pulleys using expanded polytetrafluoroethylene membrane.

    PubMed

    Bartle, B K; Telepun, G M; Goldberg, N H

    1992-03-01

    Reconstruction or replacement of the damaged pulley is a difficult surgical problem because of the need to find suitable biological material, the bulkiness of the repair, and adhesion formation between the pulley and flexor tendons. Therefore, a method was developed to reconstruct the fibro-osseous pulleys with polytetrafluoroethylene (PTFE) membrane. Twenty White Leghorn chickens had the A3 pulley of the long digit excised; this was followed by a standard injury to the flexor profundus tendon. The A3 pulley was then reconstructed with PTFE membrane. In the opposite foot, the A3 pulley was transected laterally, the tendon injured in the same manner, and the native pulley sutured. Seven control chickens had a PTFE pulley reconstruction without tendon injury in one foot and the opposite foot did not undergo surgery. At postoperative days 0, 21, and 35, the animals were killed to evaluate the effectiveness of the PTFE pulleys. Flexor tendon function was assessed by determining the active range of motion of the digit. There was no significant difference between the PTFE pulleys and suture repair of the native pulleys at postoperative days 21 and 35. This indicates that the PTFE pulleys were capable of preventing tendon bow-stringing and did not significantly impair tendon gliding. The breaking strength of the PTFE pulley was less than that of the normal A3 pulleys, but it was sufficient to allow immediate mobilization of the digits postoperatively without fear of pulley rupture. The synthetic PTFE pulley appears to have the potential to function as an effective immediate replacement for the fibro-osseous pulleys.

  15. Feasibility of a New Pulley Repair: A Cadaver Study.

    PubMed

    Schöffl, Isabelle; Meisel, Julia; Lutter, Christoph; Schöffl, Volker

    2017-10-04

    In this study, the feasibility of a new pulley reconstruction in which the tendon graft is pulled through a tunnel in the proximal phalanx, was evaluated using a cadaver model, with particular attention paid to the weakening of the bone structure by the drill hole. Nine fingers from 6 cadaver hands with intact pulley systems were compared with 9 fingers from 6 cadaver hands with missing A2 to A4 pulleys but that included a repair using the new surgical technique. Each finger was fixed to an isokinetic loading device. The forces in the flexor tendons were recorded in each finger using a force transducer. The forces recorded in the flexor tendons of the control group were significantly higher than in the reconstructed fingers. The most common event in the reconstructed fingers was graft failure. A fracture of the bone due to the drill hole was not observed. The new pulley reconstruction could represent an alternative to existing reconstructive techniques. The cause for the higher forces recorded in the control group could be attributed to sutures used in the operated fingers. The new pulley reconstruction method may enable reduced extensor tendon irritation because it avoids contact with the extensor hood and could possibly prohibit cortical bone loss, a serious side effect in the "one and one-half loop" technique. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  16. Scaffolding students' understanding of force in pulley systems

    NASA Astrophysics Data System (ADS)

    Rouinfar, Amy; Madsen, Adrian M.; Hoang, Tram Do Ngoc; Puntambekar, Sadhana; Rebello, N. Sanjay

    2013-01-01

    Recent research results have found that students using virtual manipulatives perform as well or better on measures of conceptual understanding than their peers who used physical equipment. We report on a study with students in a conceptual physics laboratory using either physical or virtual manipulatives to investigate forces in pulley systems. Written materials guided students through a sequence of activities designed to scaffold their understanding of force in pulley systems. The activity sequences facilitated students' sense making by requiring them to make and test predictions about various pulley systems by building and comparing different systems. We investigate the ways in which students discuss force while navigating the scaffolding activities and how these discussions compare between the physical and virtual treatments.

  17. Fatigue of NiTi SMA-pulley system using Taguchi and ANOVA

    NASA Astrophysics Data System (ADS)

    Mohd Jani, Jaronie; Leary, Martin; Subic, Aleksandar

    2016-05-01

    Shape memory alloy (SMA) actuators can be integrated with a pulley system to provide mechanical advantage and to reduce packaging space; however, there appears to be no formal investigation of the effect of a pulley system on SMA structural or functional fatigue. In this work, cyclic testing was conducted on nickel-titanium (NiTi) SMA actuators on a pulley system and a control experiment (without pulley). Both structural and functional fatigues were monitored until fracture, or a maximum of 1E5 cycles were achieved for each experimental condition. The Taguchi method and analysis of the variance (ANOVA) were used to optimise the SMA-pulley system configurations. In general, one-way ANOVA at the 95% confidence level showed no significant difference between the structural or functional fatigue of SMA-pulley actuators and SMA actuators without pulley. Within the sample of SMA-pulley actuators, the effect of activation duration had the greatest significance for both structural and functional fatigue, and the pulley configuration (angle of wrap and sheave diameter) had a greater statistical significance than load magnitude for functional fatigue. This work identified that structural and functional fatigue performance of SMA-pulley systems is optimised by maximising sheave diameter and using an intermediate wrap-angle, with minimal load and activation duration. However, these parameters may not be compatible with commercial imperatives. A test was completed for a commercially optimal SMA-pulley configuration. This novel observation will be applicable to many areas of SMA-pulley system applications development.

  18. Adenosine A1 receptors mediate inhibition of tachykinin release from perifused enteric nerve endings.

    PubMed

    Broad, R M; McDonald, T J; Brodin, E; Cook, M A

    1992-03-01

    A perifused preparation of guinea pig myenteric nerve varicosities (synaptosomes) was used to determine the characteristics of evoked tachykinin release and the inhibition of such release by adenosine analogues. Release of substance P-like immunoreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) was evoked by elevated extracellular [K+] in a reversible and repeatable manner. This release was completely abolished in the absence of extracellular Ca2+. Perifusion in the presence of 5'-N-ethylcarboxamidoadenosine (NECA), a nonselective A1/A2 adenosine receptor agonist, decreased K(+)-evoked release of SP-LI and NKA-LI compared with that in the absence of the nucleoside. Similar decrements in peptide release were obtained with N6-cyclopentyl adenosine (CPA), a selective A1 agonist, and 2-[p-(2-carboxyethyl)]phenethylamino-5'-N-ethyl-carboxamidoadenosi ne (CGS 21680), a selective A2 agonist. Response to all nucleosides was graded. Potency order of adenosine analogues was CPA greater than NECA much greater than CGS 21680. Inhibition due to the nucleosides was diminished in the presence of the highly selective A1-receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) while perifusion in the presence of DPCPX alone did not alter evoked release of either peptide. These findings provide direct measurements of inhibitory effects of adenine nucleosides on the release, from enteric nerve endings, of endogenous neuromediators SP and NKA. The findings also directly demonstrate the presence of functional adenosine receptors of the A1 subtype on enteric nerve endings coupled negatively to release of tachykinins. The presence of A2 receptors on enteric nerve endings is neither supported nor excluded.

  19. The results of percutaneous release of trigger digits by using full handle knife 15 degrees: an anatomical hand surface landmark and clinical study.

    PubMed

    Jongjirasiri, Yolchai

    2007-07-01

    Know the results of percutaneous release of trigger digits by using full handle knife 15 degrees. The author identified 510 cadaveric digits to find the anatomical landmark of Al pulley that relates to the knuckle and measurements of A1 pulley lengths. The proximal margin of the Al pulleys on the perpendicular line from the knuckle to the palm was in the same line in 327 (64.1%) digits, while 464 (91.0%) digits were < or =1 mm and 509 (99.8%) were < or =2 mm. The average lengths of A1 pulleys in each digit were as follows: thumb; 5.30, index finger; 6.32, middle finger; 6.58, ring finger; 6.32, and little finger 5.30 mm. The average lengths of all fingers were 6.13 mm. A further 338 digits of trigger digit in 248 patients were treated by percutaneous release by using full handle knife 15 degrees with these landmarks. Three hundred and thirty-eight trigger digits were treated. There was a complete resolution of symptoms in 314 digits (92.90%) when followed up 6 weeks after operation. One digit, an index finger had residual grade 1 after 3 weeks and complete resolution in 8 weeks. Three digits (0.89%), which were one thumb and two index fingers, underwent local steroid injection because of painful scar. Nineteen digits (5.62%) were stiff at proximal interphalangeal joint because of grade 4 triggering and osteoarthritis of the proximal interphalangeal joint but they increased the range of motion after 6 months. A case (0.30%) had numbness of the radial tip of the thumb, which may have been caused by injury to the radial digital nerve ofthe thumb. No one had open release of A1 pulley. This technique was a safe and effective out patient procedure on 248 patients and had a complete resolution of symptoms 92.90%.

  20. 7. POWERHOUSE, FOREGROUND ON CEILING EXCITER FLATBELT PULLEYS, BACK RIGHT, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. POWERHOUSE, FOREGROUND ON CEILING EXCITER FLATBELT PULLEYS, BACK RIGHT, WOODEN PERSONAL FACILITY LOCATED IN POWERHOUSE LOWER LEVEL LOOKING SOUTH - Dayville Mills Hydroelectric Facility, Powerhouse, North side of Route 101, .5 mile west of Route 395, Killingly Center, Windham County, CT

  1. 4. Scale floor detail of rope pulley systemsouth wall looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Scale floor detail of rope pulley system-south wall looking east of Peavey Duluth Terminal Elevator. - Peavey Duluth Terminal Elevator, Workhouse, South side of first slip, north from outer end of Rice's Point, east of Garfield Avenue, Duluth, St. Louis County, MN

  2. 51. DETAIL, VIEW OF CABLE SUSPENDED BRIDGE COUNTERWEIGHTS AND PULLEYS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. DETAIL, VIEW OF CABLE SUSPENDED BRIDGE COUNTERWEIGHTS AND PULLEYS FROM BRIDGE SUSPENSION STRUCTURE ON BRIDGE NO. 11. LOOKING WEST. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  3. 4. PULLEY SYSTEM AND CABLE FOR GATELIFTING MECHANISM, MOUNTED ABOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. PULLEY SYSTEM AND CABLE FOR GATE-LIFTING MECHANISM, MOUNTED ABOVE THE THREE GATE OPENINGS, LOOKING SOUTH/SOUTHEAST. - Washington Water Power Spokane River Upper Falls Hydroelectric Development, Gates & Gate-Lifting Mechanisms, Spokane River, approximately 0.5 mile northeast of intersection of Spokane Falls Boulevard & Post Street, Spokane, Spokane County, WA

  4. The Pulley Analogy Does Not Work for Every Siphon

    ERIC Educational Resources Information Center

    Planinsic, Gorazd; Slisko, Josip

    2010-01-01

    How do siphons work? Some see atmospheric pressure, explicitly or implicitly, as a crucial factor in siphon action. Others explain that a siphon works due to a difference of water weights in unequal arms. According to the latter view, siphon action is analogous to the action of a pulley or to the behaviour of a chain that is moving over a tube. In…

  5. The Real Life Application of Pulleys in a Competitive Environment

    ERIC Educational Resources Information Center

    Tekbiyik, Ahmet

    2015-01-01

    The aim of this research was to explore students' application of theoretical knowledge in real-life situations using pulley systems in a competition designed for primary school students. The study was conducted with 24 primary school students who had completed year seven, and who volunteered to participate in a summer science camp. In groups, the…

  6. The Real Life Application of Pulleys in a Competitive Environment

    ERIC Educational Resources Information Center

    Tekbiyik, Ahmet

    2015-01-01

    The aim of this research was to explore students' application of theoretical knowledge in real-life situations using pulley systems in a competition designed for primary school students. The study was conducted with 24 primary school students who had completed year seven, and who volunteered to participate in a summer science camp. In groups, the…

  7. The Pulley Analogy Does Not Work for Every Siphon

    ERIC Educational Resources Information Center

    Planinsic, Gorazd; Slisko, Josip

    2010-01-01

    How do siphons work? Some see atmospheric pressure, explicitly or implicitly, as a crucial factor in siphon action. Others explain that a siphon works due to a difference of water weights in unequal arms. According to the latter view, siphon action is analogous to the action of a pulley or to the behaviour of a chain that is moving over a tube. In…

  8. 35. DETAIL OF STRETCH SLING CYLINDER AND PULLEY LOCATED ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. DETAIL OF STRETCH SLING CYLINDER AND PULLEY LOCATED ON EAST SIDE OF SLC-3W MST STATION 85.5 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. 19. FOURTH FLOOR BLDG. 28, DETAIL BLOCKS, PULLEYS, AND ELECTRIC ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. FOURTH FLOOR BLDG. 28, DETAIL BLOCKS, PULLEYS, AND ELECTRIC MOTOR LOOKING EAST. - Fafnir Bearing Plant, Bounded on North side by Myrtle Street, on South side by Orange Street, on East side by Booth Street & on West side by Grove Street, New Britain, Hartford County, CT

  10. 30 CFR 56.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Manual cleaning of conveyor pulleys. 56.14202 Section 56.14202 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Equipment Safety Practices and Operational Procedures § 56.14202 Manual cleaning of conveyor...

  11. 30 CFR 57.14202 - Manual cleaning of conveyor pulleys.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Manual cleaning of conveyor pulleys. 57.14202 Section 57.14202 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... and Equipment Safety Practices and Operational Procedures § 57.14202 Manual cleaning of...

  12. [Three-dimensional distribution and histological studies of extraocular muscle Pulley in human orbit].

    PubMed

    Han, Xiao-mei; Zhao, Kan-xing; Qian, Xue-han

    2005-09-01

    To study the structure and three-dimensional distribution of extraocular muscle Pulley in orbit. 5 fresh cadaver orbits were fixed in situ and serially sectioned at 4 microm thickness. Every nearby sections were stained using Masson's trichrome, Van Gieson'stain and immunohistochemical staining, the stained tissue was examined by gross anatomy and light microscopy. Near the equator of the globe, extraocular muscle Pulleys were at the points where rectus penetrate posterior Tenon's fascia, encircling the rectus orbit side by fiber ring structure. There was Pulley Band among extraocular muscle Pulleys. The main composition of the Pulley and Pulley Band were collagen (I and III type), elastic and smooth muscle. Constitution of Pulley provides dissection basis as the functional origins of the extraocular muscle.

  13. Adenosine transiently modulates stimulated dopamine release in the caudate-putamen via A1 receptors.

    PubMed

    Ross, Ashley E; Venton, B Jill

    2015-01-01

    Adenosine modulates dopamine in the brain via A1 and A2A receptors, but that modulation has only been characterized on a slow time scale. Recent studies have characterized a rapid signaling mode of adenosine that suggests a possible rapid modulatory role. Here, fast-scan cyclic voltammetry was used to characterize the extent to which transient adenosine changes modulate stimulated dopamine release (5 pulses at 60 Hz) in rat caudate-putamen brain slices. Exogenous adenosine was applied and dopamine concentration monitored. Adenosine only modulated dopamine when it was applied 2 or 5 s before stimulation. Longer time intervals and bath application of 5 μM adenosine did not decrease dopamine release. Mechanical stimulation of endogenous adenosine 2 s before dopamine stimulation also decreased stimulated dopamine release by 41 ± 7%, similar to the 54 ± 6% decrease in dopamine after exogenous adenosine application. Dopamine inhibition by transient adenosine was recovered within 10 min. The A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine blocked the dopamine modulation, whereas dopamine modulation was unaffected by the A2A receptor antagonist SCH 442416. Thus, transient adenosine changes can transiently modulate phasic dopamine release via A1 receptors. These data demonstrate that adenosine has a rapid, but transient, modulatory role in the brain. Here, transient adenosine was shown to modulate phasic dopamine release on the order of seconds by acting at the A1 receptor. However, sustained increases in adenosine did not regulate phasic dopamine release. This study demonstrates for the first time a transient, neuromodulatory function of rapid adenosine to regulate rapid neurotransmitter release.

  14. [The Omega "Omega" pulley plasty: a new technique for the surgical management of the De Quervain's disease].

    PubMed

    Bakhach, J; Sentucq-Rigal, J; Mouton, P; Boileau, R; Panconi, B; Guimberteau, J-C

    2006-02-01

    The Omega "Omega" pulley plasty: a new technique for the surgical management of the De Quervain's disease. The De Quervain tenosynovitis is an inadequacy into the first extensor compartment between the osteo-fibrous tunnel and the tendons. This mechanical conflict generates a tenosynovitis of the extensor pollicis brevis and the abductor pollicis longus tendons. This is generally expressed by a tenderness on the radial side of the wrist over the radial styloid process. The medical management consists on corticoids infiltrations of the first extensor compartment, the avoidance of repetitive and stress movements of the first ray with the use of a rest splint. The surgical approach is considered with the recurrence of the painful symptoms. This well-known pathology is reputated to require a simple section of the pulley. Our post-operative complications have been reported in the literature of this classical surgical solution. These complications concern an incomplete release of the extensor pollicis brevis and the abductor pollicis longus tendons particularly when an extensor sub-compartment exists and was overlooked, an irritation of the collateral branches of the sensitive radial nerve or the occurrence of a nevroma after a nerve injury and the most serious complication is a palmar subluxation of the extensor tendons which can occur with the thumb extended and the wrist flexed. In rare cases, this subluxation can be really painful and requires a surgical management with secondary reconstruction of the pulley. This reconstruction necessitates distal pedicle flaps from the dorsal retinaculum or the brachioradialis tendon. To prevent these complications, Codega and Kapandji described techniques of reconstruction of the pulley after its release. More recently, Le Viet reported a procedure using the anterior flap of the pulley; fixed to the dermis it will work as a barrier and maintain the tendons sliding on the radial styloid groove. These techniques require to divide

  15. Flap irritation phenomenon (FLIP): etiology of chronic tenosynovitis after finger pulley rupture.

    PubMed

    Schöffl, Isabelle; Baier, Thomas; Schöffl, Volker

    2011-11-01

    After a pulley rupture, most climbers regain the full function of their previously uninjured fingers. However, in some cases of pulley rupture, a persistent inflammation of the tendon sheath is observed. In this study, 16 cadaver fingers were loaded until pulley rupture and then studied for the rupturing mechanism. In addition, two patients with this pathology were investigated using ultrasound and MRI, and received surgery. In 13 fingers, a rupture of one or several pulleys occurred and almost always at the medial or lateral insertion. In one finger, a capsizing of the pulley underneath the intact tendon sheath was observed, leading to an avulsion between tendon and tendon sheath. A similar pathology was observed in the ultrasound imaging, in MRI, and during surgery in two patients with prolonged recovery after minor pulley rupture. In cases of prolonged tenosynovitis after minor pulley rupture, a capsizing of the pulley stump is probably the cause for constant friction leading to inflammation. In those cases, a surgical removal of the remaining pulley stump and sometimes a pulley repair may be necessary.

  16. Adenosine transiently modulates stimulated dopamine release in the caudate putamen via A1 receptors

    PubMed Central

    Ross, Ashley E.; Venton, B. Jill

    2014-01-01

    Adenosine modulates dopamine in the brain via A1 and A2A receptors, but that modulation has only been characterized on a slow time scale. Recent studies have characterized a rapid signaling mode of adenosine that suggests a possible rapid modulatory role. Here, fast-scan cyclic voltammetry was used to characterize the extent to which transient adenosine changes modulate stimulated dopamine release (5 pulses at 60 Hz) in rat caudate putamen brain slices. Exogenous adenosine was applied and dopamine concentration monitored. Adenosine only modulated dopamine when it was applied 2 or 5 s before stimulation. Longer time intervals and bath application of 5 µM adenosine did not decrease dopamine release. Mechanical stimulation of endogenous adenosine 2s before dopamine stimulation also decreased stimulated dopamine release by 41 ± 7 %, similar to the 54 ± 6 % decrease in dopamine after exogenous adenosine application. Dopamine inhibition by transient adenosine was recovered within 10 minutes. The A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) blocked the dopamine modulation, whereas dopamine modulation was unaffected by the A2A receptor antagonist SCH 442416. Thus, transient adenosine changes can transiently modulate phasic dopamine release via A1 receptors. These data demonstrate that adenosine has a rapid, but transient, modulatory role in the brain. PMID:25219576

  17. The Pulley: A Parable of Effort and Reward

    NASA Astrophysics Data System (ADS)

    Gluck, Paul

    2012-11-01

    The Alwood machine and various problems involving pulleys are sta(p)le diets of students when applying Newton's second law of motion. Interest in such problems can be increased and discussion enlivened by couching them in forms that have in them elements of suspense (sic!) or competition. Two didactic papers have suggested versions in this vein.1,2 Here we should like to present a discussion that contrasts models and theoretical constructs with a reallife situation. A mathematician N and a physicist P having identical masses m sit at the same height at the ends of a rope passing over a pulley, as in Fig. 1(a). They decide on a race to climb up the rope, the first one to reach the pulley wins. Which one of them will be the winner? Is it prudent to work hard, or does the indolent get there first by mere force of thought? The following qualitative discussion could be of interest when introducing the class to the Atwood machine.

  18. On static contact of belt and different pulleys

    NASA Astrophysics Data System (ADS)

    Belyaev, A. K.; Eliseev, V. V.; Irschik, H.; Oborin, E. A.

    2017-06-01

    The fitting of a looped belt on two pulleys with different radii is considered. A geometrically nonlinear model with account for tension and transverse shear is applied for modeling the belt. The pulleys are considered rigid bodies, and the belt-pulley contact is assumed frictionless. The problem has an axis of symmetry, therefore the boundary value problem is formulated and solved for a half of the belt. The considered part consists of three segments, two contact segments and a free span segment between them. The introduction of a dimensionless material coordinate at all segments leads to a system of ordinary differential equations of fifteenth order. The nonlinear boundary value problem for this system and boundary conditions is solved numerically with the shooting method and the finite difference method. As a result, the belt shape including the rotation angle, the forces, moments and contact pressure are determined. The contact pressure increases near the end point of contact areas, however no concentrated contact forces occur.

  19. Considerations in the surgical use of the flexor sheath and pulley system.

    PubMed

    Lowrie, A G; Lees, V C

    2014-01-01

    The use of the digital flexor sheath to reconstruct damaged structures in the fingers is an intriguing but under-investigated subject. The sheath is anchored firmly to the phalanges and palmar plates and has well-vascularized outer and synovial inner layers. The middle layer is strong and fibrous and not all of it is required for its main biomechanical function of maintaining the moment arm of the flexor tendons. These characteristics have led to several descriptions of different reconstructive uses. In sheath reconstruction, flaps can be used to repair damaged A2 and A4 pulleys. As an anchor, the sheath is useful for tenodeses and tendon transfers. It has been used in the correction of ulnar claw and swan neck deformities. In ligament reconstruction, the A1 pulley has been used to reconstruct the transverse intermetacarpal ligament in cleft hand and ray amputations. The sheath has also been used to cover tendon repairs and periosteal defects with the aim of decreasing adhesions. There is potential for further use of the flexor sheath in reconstructive surgery. The digital flexor sheath can be used to restore various finger functions providing its physiological roles are recognized and preserved. This review considers the different techniques described and their potential uses.

  20. Comparing the development of students' conceptions of pulleys using physical and virtual manipulatives

    NASA Astrophysics Data System (ADS)

    Rouinfar, Amy; Madsen, Adrian M.; Hoang, Tram Do Ngoc; Puntambekar, Sadhana; Rebello, N. S.

    2012-02-01

    Research has shown that the concept of force in a pulley is learned equally well by students using physical and virtual manipulatives. We report on a study in which students enrolled in a conceptual physics laboratory spent two weeks investigating pulley systems using either physical or virtual manipulatives. Students were given written materials which guided them through a series of activities which scaffolded the construction of their conceptions of pulleys. Students were required to make predictions and then test these predictions by building and comparing different pulley systems. They were presented with a challenge to design the best pulley system to lift a piano at the end of each week. We compare how the students' conceptions of pulleys develop between the physical and virtual treatments as well as investigate the ways in which they use the manipulatives while completing the scaffolding activities.

  1. Three-dimensional location of human rectus pulleys by path inflections in secondary gaze positions.

    PubMed

    Clark, R A; Miller, J M; Demer, J L

    2000-11-01

    Connective tissue pulleys serve as the functional mechanical origins of the extraocular muscles (EOMs). Anterior to these pulleys, EOM paths shift with gaze to follow the scleral insertions, whereas posterior EOM paths are stable in the orbit. Inflections in EOM paths produced by gaze shifts can be used to define the functional location of pulleys in three dimensions (3-D). Contiguous magnetic resonance images in planes perpendicular to the orbital axis spanned the anteroposterior extents of 22 orbits of 11 normal adults with the eyes in central gaze, elevation, depression, abduction, and adduction. Mean EOM cross-sectional area centroids represented in a normalized, oculocentric coordinate system were plotted over the length of each EOM to determine paths. Path inflections were identified to define pulley locations in 3-D. All rectus EOM paths exhibited in secondary gaze positions distinct inflections 3 to 9 mm posterior to globe center, which were consistent across subjects. The globe center and the lateral rectus pulley translated systematically in the orbit with lateral gaze, whereas other pulleys remained stable relative to the orbit. Distinct inflections in rectus EOM paths in secondary gaze positions confirm the existence of pulleys and define their locations in 3-D. The globe and lateral rectus pulley translate systematically with gaze position. The EOM pulleys may simplify neural control of eye movements by implementing a commutative ocular motor plant in which commands for 3-D eye velocity are effectively independent of eye position.

  2. Non-linear dynamics of a one-way clutch in belt-pulley systems

    NASA Astrophysics Data System (ADS)

    Zhu, Farong; Parker, R. G.

    2005-01-01

    One-way clutches are frequently used in the serpentine belt accessory drives of automobiles and heavy vehicles. The clutch plays a role similar to a vibration absorber in order to reduce belt/pulley vibration and noise and increase belt life. This paper analyzes a two-pulley system where the driven pulley has a one-way clutch between the pulley and accessory shaft that engages only for positive relative displacement between these components. The belt is modelled with linear springs that transmit torque from the driving pulley to the accessory pulley. The one-way clutch is modelled as a piecewise linear spring with discontinuous stiffness that separates the driven pulley into two degrees of freedom. The harmonic balance method combined with arclength continuation is employed to illustrate the non-linear dynamic behavior of the one-way clutch and determine the stable and unstable periodic solutions for given parameters. The results are confirmed by numerical integration and the bifurcation software AUTO. At the first primary resonance, most of the responses are aperiodic, including quasiperiodic and chaotic solutions. At the second primary resonance, the peak bends to the left with classical softening non-linearity because clutch disengagement decouples the pulley and the accessory over portions of the response period. The dependence on clutch stiffness, excitation amplitude, and inertia ratio between the pulley and accessory is studied to characterize the non-linear dynamics across a range of conditions.

  3. Pulley lesions in rotator cuff tears: prevalence, etiology, and concomitant pathologies.

    PubMed

    Hawi, Nael; Liodakis, Emmanouil; Garving, Christina; Habermeyer, Peter; Tauber, Mark

    2017-08-01

    This study aimed to demonstrate the prevalence of lesions in the biceps pulley complex in a representative, consecutive series of rotator cuff tears and rotator cuff interval treatments. We also analyzed associated tear pattern of rotator cuff injuries and superior labrum anterior-posterior (SLAP) lesions. We evaluated the relationships of these lesions to traumatic genesis and the prevalence of pulley lesions in revision cases. This retrospective study analyzed all pre- and intra-operative documentation on arthroscopic rotator cuff reconstructions and isolated pulley lesion treatments performed by a single surgeon over 2 consecutive years. According to Habermeyer et al., we classified cases into four groups, based on the presence of additional or related complete or partial rotator cuff tears, SLAP lesions, trauma, and primary or revision surgery. Among 382 patients with rotator cuff tears, 345 (90.3%) had an injured pulley system; 151 (43.8%) had partial tears of the rotator cuff; out of these, 106 (30.6%) were articular-sided. All of these articular-sided partial tears showed extension into the pulley complex. In 154 cases (44.6%), history of shoulder trauma was associated with the beginning of symptoms. In addition, concomitant SLAP lesions occurred in 25-62% of pulley lesions, correlating with the severity of pulley lesions. Among the 345 cases, there have been 32 (9.3%) revision cases where a pulley lesion was intra-operatively identified and addressed. Pulley complex lesions are present in 90.3% of surgically treated rotator cuff lesions, particularly in articular-sided injuries. In addition, we found a significant relationship between the incidence of SLAP lesions and the severity of pulley lesions. It seems reasonable to assume an important role of pulley system injuries in the pathogenesis of rotator cuff lesions.

  4. Functional anatomy of the human digital flexor pulley system.

    PubMed

    Lin, G T; Amadio, P C; An, K N; Cooney, W P

    1989-11-01

    The anatomy of 55 cadaver digits was studied, both statistically and with simulated active motion using weights attached to the flexor tendons. The modified description of Doyle and Blythe accurately described the anatomy observed. Serial pulley sectioning showed two types of bowstringing, both of which affected the relationship of tendon excursion to joint motion. The most constant, resulting in 15% loss of motion for a fixed tendon excursion, occurred over the concave surfaces of the proximal and middle phalanges. Bowstringing at the proximal interphalangeal joint was present only after 30 degrees of flexion had occurred, because of the convexity of the phalangeal condyles.

  5. The Effect of Friction in Pulleys on the Tension in Cables and Strings

    ERIC Educational Resources Information Center

    Martell, Eric C.; Martell, Verda Beth

    2013-01-01

    Atwood's machine is used in countless introductory physics classes as an illustration of Newton's second law. Initially, the analysis is performed assuming the pulley and string are massless and the axle is frictionless. Although the mass of the pulley is often included when the problem is revisited later in the context of rotational dynamics, the…

  6. The Effect of Friction in Pulleys on the Tension in Cables and Strings

    ERIC Educational Resources Information Center

    Martell, Eric C.; Martell, Verda Beth

    2013-01-01

    Atwood's machine is used in countless introductory physics classes as an illustration of Newton's second law. Initially, the analysis is performed assuming the pulley and string are massless and the axle is frictionless. Although the mass of the pulley is often included when the problem is revisited later in the context of rotational dynamics, the…

  7. [Tendinitis of the long head of biceps tendon associated with lesions of the "biceps reflection pulley"].

    PubMed

    Werner, A; Ilg, A; Schmitz, H; Gohlke, F

    2003-06-01

    In some patients with persistent pain around the Long Head of Biceps Tendon (LHB), lesions of the "biceps reflection pulley", associated with biceps tendinitis, can be found. The aim of this study is to describe the anatomy of the reflection pulley and the arthroscopic appearance of the pulley lesion. Therapeutic options will be discussed. The results of a former histo-anatomic study done by the authors in 13 cadaver shoulders are compared with the intra-operative findings in patients with persistent tendinitis of the LHB together with a lesion of the reflection pulley and signs of LHB instability. Intra-operative findings from patients with either posttraumatic anterior instability or calcific tendinitis served as control. The superior glenohumeral ligament (SGHL) together with the coraco-humeral ligament (CHL) and fibers from the subscapularis and supraspinatus tendons form a stabilizing reflection pulley for the LHB in the rotator cuff interval. Arthroscopy shows an association between a lesion of this pulley and persistent LHB-tendinitis. Pulley lesions can occur as isolated ligamentous pathology or together with a partial detachment of rotator cuff tendons. In patients with therapy-resistant pain around the LHB, lesions of the reflection pulley need to be excluded beside more common causes of biceps problems. Arthroscopy is a reliable tool to assess these lesions. Therapy should address the definite pathology.

  8. The influence of the crimp and slope grip position on the finger pulley system.

    PubMed

    Schöffl, I; Oppelt, K; Jüngert, J; Schweizer, A; Neuhuber, W; Schöffl, V

    2009-09-18

    In this study the influence of the grip position (crimp grip vs. slope grip position) on the pulley system of the finger was investigated. For this purpose 21 cadaver finger (11 hands, 10 donors) were fixed into an isokinetic loading device. Nine fingers were loaded in the slope grip position and 12 fingers in the crimp grip position. The forces in the flexor tendons and at the fingertip were recorded. A rupture of the A4 pulley occurred most often in the crimp grip position (50%) but did not occur in the slope grip position, in which alternative events were the most common (67%). The forces in the deep flexor tendon (FDP) (slope grip: 371 N, crimp grip: 348 N) and at the fingertip (slope grip: 105 N, crimp grip: 161 N) were not significantly different between the 2 finger positions, but the forces acting on the pulleys were higher in the crimp grip position (A2 pulley: 287 N, A4 pulley: 226 N) than in the slope grip position (A2 pulley: 121 N, A4 pulley: 103 N). The crimp grip position may be the main cause for A4 pulley ruptures but the slope grip position may be hazardous for other injuries as the forces recorded in the flexor tendons and at the fingertip were comparable at the occurrence of a terminal event.

  9. Feasibility of partial A2 and A4 pulley excision: effect on finger flexor tendon biomechanics.

    PubMed

    Mitsionis, G; Bastidas, J A; Grewal, R; Pfaeffle, H J; Fischer, K J; Tomaino, M M

    1999-03-01

    We investigated the effect of partial excision of the A2 and A4 digital pulleys, separately and in combination, on finger angular rotation and the energy for finger flexion. Statistically significant decreases in angular rotation resulted only after 50% and 75% excision of A2, A4, or A2 and A4 in combination. Work of flexion trends were weak and none of the changes were statistically significant. Although optimal finger function relies on the integrity of the A2 and A4 pulleys to maintain the efficiency of the digital flexor system, these data suggest that the A2 and A4 pulleys can be excised up to 25%, either separately or in combination, without significant effects on angular rotation. Decreases in total angular range of motion after 50% and 75% pulley excision were small, even for combined pulley excision (9 degrees +/- 3 degrees and 15 degrees +/- 5 degrees [mean +/- SD], respectively), and may be clinically acceptable.

  10. Crouzon syndrome: relationship of rectus muscle pulley location to pattern strabismus.

    PubMed

    Weiss, Avery H; Phillips, James; Kelly, John P

    2014-01-15

    Investigate the relationship between the extorsion of the rectus muscle pulleys and the V-pattern exotropia and "overelevation in adduction" observed in Crouzon syndrome. Twenty children with Crouzon syndrome had assessment of eye alignment. The horizontal and vertical positions of the four rectus muscle pulleys were estimated from coronal CT images. Eye alignment was simulated in Orbit 1.8 software by shifting the corresponding location of the rectus muscle pulley array. Eleven of the 20 patients had a V-pattern exotropia with displacements of each rectus muscle pulley ranging from 2 to 7 mm. The remaining nine patients were orthotropic with <2 mm displacement of the rectus muscle pulleys. Simulated displacements (>2 mm) of either the horizontal or vertical rectus muscle pulleys produced a similar strabismus pattern. The amount of V-pattern exotropia observed clinically was highly correlated with the amount predicted by pulley displacements in Orbit 1.8 (r(2) = 0.63; P < 0.0001). The displacement of vertical and horizontal rectus muscle pairs was significantly higher for patients having overelevation in adduction. Rotation of the four rectus muscle pulleys relative to the corresponding rotation planes of the globe changes the direction and magnitude of their active and passive pulling forces in a gaze-dependent manner. Extorsion of the horizontal and vertical rectus muscle pulleys in Orbit 1.8 reproduces the pattern strabismus observed in Crouzon syndrome. The high correlation between the predicted magnitude of the V-pattern exotropia and observed exotropia indicates that extorsion of the rectus muscle pulleys primarily accounts for the pattern strabismus.

  11. Pulley Ruptures in Rock Climbers: Outcome of Conservative Treatment With the Pulley-Protection Splint-A Series of 47 Cases.

    PubMed

    Schneeberger, Micha; Schweizer, Andreas

    2016-06-01

    To evaluate the effectiveness of conservative treatment of finger flexor tendon pulley rupture with a pulley-protection splint (PPS) with regard to reduction in tendon-phalanx distance (TPD) and functional and sport-specific outcomes in a retrospective case series. Tendon-phalanx distance in active forced flexion was measured before and after treatment in ultrasound records. Functional and sport-specific outcomes were evaluated by means of a questionnaire, which also contained instructions for self-measurement of finger range of motion and finger strength. Forty-seven complete pulley ruptures in 45 rock climbers (mean age, 33.4 years; range, 21.8-56.2 years) were included in the study. In the 39 patients who had follow-up ultrasound examination, PPS treatment decreased mean ± SD TPD from 4.4 ± 1.0 mm to 2.3 ± 0.6 mm after A2 pulley rupture and from 2.9 ± 0.7 mm to 2.1 ± 0.5 mm after A4 pulley rupture. Tendon-phalanx distance was reduced in all patients. Finger range of motion (n = 42) and finger strength (n = 22) did not differ significantly between treated and contralateral sides. Of the 43 climbers who completed questionnaires, 38 had regained their previous climbing level a mean 8.8 months after pulley rupture; 1 reported reduced finger dexterity; 39 assessed their treatment results to be good, and 4 to be very good. The PPS is an effective conservative treatment modality for pulley ruptures, which reduces TPD and enables the patient to regain previous finger function. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  12. Periodic responses of a pulley-belt system with one-way clutch under inertia excitation

    NASA Astrophysics Data System (ADS)

    Ding, Hu

    2015-09-01

    The stable steady-state periodic response of a two-pulley belt drive system coupled with an accessory by a one-way clutch is presented. For the first time, the pulley-belt system is studied under double excitations. Specifically, the dual excitations consist of harmonic motion of the driving pulley and inertia excitation. The belt spans are modeled as axially moving viscoelastic beams by considering belt bending stiffness. Therefore, integro-partial-differential equations are derived for governing the transverse vibrations of the belt spans. Moreover, the transverse vibrations of the moving belt are coupled with the rotation vibrations of the pulleys by nonlinear dynamic tension. For describing the unidirectional decoupling function of the one-way device, rotation vibrations of the driven pulley and accessory are modeled as coupled piecewise ordinary differential equations. In order to eliminate the influence of the boundary of the belt spans, the non-trivial equilibriums of the pulley-belt system are numerically determined. Furthermore, A nonlinear piecewise discrete-continuous dynamical system is derived by introducing a coordinate transform. Coupled vibrations of the pulley-belt system are investigated via the Galerkin truncation. The natural frequencies of the coupled vibrations are obtained by using the fast Fourier transform. Moreover, frequency-response curves are abstracted from time histories. Therefore, resonance areas of the belt spans, the driven pulley and the accessory are presented. Furthermore, validity of the Galerkin method is examined by comparing with the differential and integral quadrature methods (DQM & IQM). By comparing the results with and without one-way device, significant damping effect of clutch on the dynamic response is discovered. Furthermore, the effects of the intensity of the driving pulley excitation and the inertia excitation are studied. Moreover, numerical results demonstrate that the two excitations interact on the steady

  13. Injuries to the finger flexor pulley system in rock climbers: current concepts.

    PubMed

    Schöffl, Volker Rainer; Schöffl, Isabelle

    2006-04-01

    Closed traumatic ruptures of finger flexor tendon pulleys began to be recognized specifically over the past several decades. This injury, although rare in the general population, is seen more commonly in rock climbers. This article analyzes this type of injury and the current diagnostic and therapeutic criteria. Ultrasound and magnetic resonance imaging are used to differentiate between a pulley strain, partial rupture, complete rupture, or multiple ruptures. Grade I to III injuries (strains, partial rupture, single ruptures) are treated conservatively with initial immobilization and early functional therapy under pulley protection. Grade IV injuries (multiple ruptures) require surgical repair.

  14. Glucocorticoid-stimulated, transcription-independent release of annexin A1 by cochlear Hensen cells

    PubMed Central

    Kalinec, F; Webster, P; Maricle, A; Guerrero, D; Chakravarti, DN; Chakravarti, B; Gellibolian, R; Kalinec, G

    2009-01-01

    Background and purpose: The current clinical strategy to protect the auditory organ against inflammatory damage by migrating leukocytes is the local delivery of glucocorticoids. However, the mechanism by which glucocorticoids confer this protection remains unknown. Therefore, we investigated the cellular and molecular targets of glucocorticoids in the cochlea that could be involved in preventing leukocyte migration. Experimental approach: We used microscopy as well as immunocytochemical and microfluidic techniques to elucidate the effect of dexamethasone, hydrocortisone and prednisolone on the cellular and intracellular distribution of annexin A1 (ANXA1) – a glucocorticoid target known to inhibit leukocyte migration by receptor-mediated signalling – in the cochlea and isolated cochlear cells of guinea pigs. Key results: All the cells lining the scala media – the cochlear compartment containing the auditory organ – express ANXA1 and the ANXA1 receptor FPR2/ALX is present in the scala media, as well as in other cochlear ducts. The majority of ANXA1 in the scala media is stored inside lipid droplets within cochlear Hensen cells. Glucocorticoids activate a myosin IIC-mediated mechanism that drives ANXA1 from the lipid droplets to the apical region of the Hensen cells, where ANXA1 is released to the external milieu by a process involving ABC transporters. Conclusions and implications: These findings suggest that ANXA1 could be a major mediator of the anti-inflammatory effects of glucocorticoids in the cochlea and identify new molecular targets for prevention of sudden sensorineural hearing loss. PMID:19912231

  15. Evaluation of finger A3 pulley rupture in the crimp grip position-a magnetic resonance imaging cadaver study.

    PubMed

    Bayer, Thomas; Adler, Werner; Schweizer, Andreas; Schöffl, Isabelle; Uder, Michael; Janka, Rolf

    2015-09-01

    The correct diagnosis of an A3 pulley rupture is challenging for musculoskeletal radiologists. An A3 pulley rupture should in theory influence the shape of the proximal interphalangeal joint volar plate (VP) and the amount of bowstringing at level of the VP during finger flexion. The purpose of this study was to perform MRI with metric analysis of the VP configuration and VP bowstringing in cadaver fingers in the crimp grip position and to determine cut points for A3 pulley rupture. MRI in the crimp grip position was performed in 21 cadaver fingers with artificially created flexor tendon pulley tears (fingers with A3 pulley rupture n = 16, fingers without A3 pulley rupture n = 5). The distances of the translation of the VP relative to the middle phalanx base, the distances between the flexor tendons and the VP body, and the distances between the flexor tendon and bone (TB) were measured. Statistical analysis showed significantly lower VP translation distances and significantly higher VP tendon distances if the A3 pulley was ruptured. A2 TB and A4 TB distances did not differ significantly in specimens with and without A3 pulley rupture. The optimal cut points for A3 pulley rupture were a VP translation distance <2.8 mm and a VP tendon distance >1.4 mm. Reduction of the VP translation distance and augmentation of the VP tendon distance are suitable indirect signs of A3 pulley rupture.

  16. Flexor digitorum superficialis repair outside the A2 pulley after zone II laceration: gliding and bowstringing.

    PubMed

    Geary, Michael B; English, Christopher; Yaseen, Zaneb; Stanbury, Spencer; Awad, Hani; Elfar, John C

    2015-04-01

    To evaluate the changes in maximum flexion angle, gliding coefficient, and bowstringing after a combined repair of both flexor tendons with the flexor digitorum superficialis (FDS) rerouted outside the A2 pulley in cadaveric hands. We performed 4 different repairs on cadaveric hands, with each repair tested on 9 unique digits. In total, 12 cadaveric hands and 36 digits were used. The thumb and little finger were removed from each hand and excluded from testing. Group 1 was sham surgery. Group 2 combined flexor digitorum profundus (FDP) and FDS laceration and repair with both slips of the FDS repaired inside the A2 pulley. Group 3 was FDP repair with one slip of the FDS repaired inside A2 and the other slip left unrepaired. Group 4 was FDP repair with both slips of the FDS rerouted and repaired outside the A2 pulley. Maximum flexion angle, gliding coefficient, and bowstringing were measured in simulated active digital motion for each group. Rerouting and repairing the FDS outside the A2 pulley (group 4) significantly lowered gliding coefficient compared with repairs with both slips inside A2, with values similar to sham surgery. We observed no significant differences in maximum flexion angle among the 4 groups. Increased bowstringing was observed with both slips of the FDS repaired and rerouted outside the A2 pulley. In this cadaveric model, repair of both slips of the FDS outside the A2 pulley improved the gliding coefficient relative to repair within the A2 pulley, which suggests decreased resistance to finger flexion. Repair of the FDS outside the A2 pulley led to a slight increase in bowstringing of the FDS tendon. We describe a technique for managing combined laceration of the FDP and FDS tendons that improves gliding function and merits consideration. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  17. The Role of Extraocular Muscle Pulleys in Incomitant Non-Paralytic Strabismus

    PubMed Central

    Clark, Robert A.

    2015-01-01

    The rectus extraocular muscles (EOMs) and inferior oblique muscle have paths through the orbit constrained by connective tissue pulleys. These pulleys shift position during contraction and relaxation of the EOMs, dynamically changing the biomechanics of force transfer from the tendon onto the globe. The paths of the EOMs are tightly conserved in normal patients and disorders in the location and/or stability of the pulleys can create patterns of incomitant strabismus that may mimic oblique muscle dysfunction and cranial nerve paresis. Developmental disorders of pulley location can occur in conjunction with large, obvious abnormalities of orbital anatomy (e.g., craniosynostosis syndromes) or subtle, isolated abnormalities in the location of one or more pulleys. Acquired disorders of pulley location can be divided into four broad categories: Connective tissue disorders (e.g., Marfan syndrome), globe size disorders (e.g., high myopia), senile degeneration (e.g., sagging eye syndrome), and trauma (e.g., orbital fracture or postsurgical). Recognition of these disorders is important because abnormalities in pulley location and movement are often resistant to standard surgical approaches that involve strengthening or weakening the oblique muscles or changing the positions of the EOM insertions. Preoperative diagnosis is aided by: (1) Clinical history of predisposing risk factors, (2) observation of malpositioning of the medial canthus, lateral canthus, and globe, and (3) gaze-controlled orbital imaging using direct coronal slices. Finally, surgical correction frequently involves novel techniques that reposition and stabilize the pulley and posterior muscle belly within the orbit using permanent scleral sutures or silicone bands without changing the location of the muscle's insertion. PMID:26180464

  18. The Role of Extraocular Muscle Pulleys in Incomitant Non-Paralytic Strabismus.

    PubMed

    Clark, Robert A

    2015-01-01

    The rectus extraocular muscles (EOMs) and inferior oblique muscle have paths through the orbit constrained by connective tissue pulleys. These pulleys shift position during contraction and relaxation of the EOMs, dynamically changing the biomechanics of force transfer from the tendon onto the globe. The paths of the EOMs are tightly conserved in normal patients and disorders in the location and/or stability of the pulleys can create patterns of incomitant strabismus that may mimic oblique muscle dysfunction and cranial nerve paresis. Developmental disorders of pulley location can occur in conjunction with large, obvious abnormalities of orbital anatomy (e.g., craniosynostosis syndromes) or subtle, isolated abnormalities in the location of one or more pulleys. Acquired disorders of pulley location can be divided into four broad categories: Connective tissue disorders (e.g., Marfan syndrome), globe size disorders (e.g., high myopia), senile degeneration (e.g., sagging eye syndrome), and trauma (e.g., orbital fracture or postsurgical). Recognition of these disorders is important because abnormalities in pulley location and movement are often resistant to standard surgical approaches that involve strengthening or weakening the oblique muscles or changing the positions of the EOM insertions. Preoperative diagnosis is aided by: (1) Clinical history of predisposing risk factors, (2) observation of malpositioning of the medial canthus, lateral canthus, and globe, and (3) gaze-controlled orbital imaging using direct coronal slices. Finally, surgical correction frequently involves novel techniques that reposition and stabilize the pulley and posterior muscle belly within the orbit using permanent scleral sutures or silicone bands without changing the location of the muscle's insertion.

  19. Modified-release oral calcifediol corrects vitamin D insufficiency with minimal CYP24A1 upregulation.

    PubMed

    Petkovich, Martin; Melnick, Joel; White, Jay; Tabash, Samir; Strugnell, Stephen; Bishop, Charles W

    2015-04-01

    Vitamin D insufficiency is prevalent in chronic kidney disease (CKD) and associated with secondary hyperparathyroidism (SHPT) and increased risk of bone and vascular disease. Unfortunately, supplementation of stage 3 or 4 CKD patients with currently recommended vitamin D2 or D3 regimens does not reliably restore serum total 25-hydroxyvitamin D to adequacy (≥30ng/mL) or effectively control SHPT. Preclinical and clinical studies were conducted to evaluate whether the effectiveness of vitamin D repletion depends, at least in part, on the rate of repletion. A modified-release (MR) oral formulation of calcifediol (25-hydroxyvitamin D3) was developed which raised serum 25-hydroxyvitamin D3 and calcitriol levels gradually. Single doses of either bolus intravenous (IV) or oral MR calcifediol were administered to vitamin D deficient rats. Bolus IV calcifediol produced rapid increases in serum 25-hydroxyvitamin D3, calcitriol and FGF23, along with significant induction of CYP24A1 in both kidney and parathyroid gland. In contrast, oral MR calcifediol produced gradual increases in serum 25-hydroxyvitamin D3 and calcitriol and achieved similar hormonal exposure, yet neither CYP24A1 nor FGF23 were induced. A 10-fold greater exposure to bolus IV than oral MR calcifediol was required to similarly lower intact parathyroid hormone (iPTH). Single doses of oral MR (450 or 900μg) or bolus IV (450μg) calcifediol were administered to patients with stage 3 or 4 CKD, SHPT and vitamin D insufficiency. Changes in serum 25-hydroxyvitamin D3 and calcitriol and in plasma iPTH were determined at multiple time-points over the following 42 days. IV calcifediol produced abrupt and pronounced increases in serum 25-hydroxyvitamin D3 and calcitriol, but little change in plasma iPTH. As in animals, these surges triggered increased vitamin D catabolism, as evidenced by elevated production of 24,25-dihydroxyvitamin D3. In contrast, MR calcifediol raised serum 25-hydroxyvitamin D3 and calcitriol

  20. Apolipoprotein A-1 (apoA-1) deposition in, and release from, the enterocyte brush border: a possible role in transintestinal cholesterol efflux (TICE)?

    PubMed

    Danielsen, E Michael; Hansen, Gert H; Rasmussen, Karina; Niels-Christiansen, Lise-Lotte; Frenzel, Franz

    2012-03-01

    Transintestinal cholesterol efflux (TICE) has been proposed to represent a non-hepatobiliary route of cholesterol secretion directly "from blood to gut" and to play a physiologically significant role in excretion of neutral sterols, but so far little is known about the proteins involved in the process. We have previously observed that apolipoprotein A-1 (apoA-1) synthesized by enterocytes of the small intestine is mainly secreted apically into the gut lumen during fasting where its assembly into chylomicrons and basolateral discharge is at a minimal level. In the present work we showed, both by immunomicroscopy and subcellular fractionation, that a fraction of the apically secreted apoA-1 in porcine small intestine was not released from the cell surface but instead deposited in the brush border. Cholesterol was detected in immunoisolated microvillar apoA-1, and it was partially associated with detergent resistant membranes (DRMs), indicative of localization in lipid raft microdomains. The apolipoprotein was not readily released from microvillar vesicles by high salt or by incubation with phosphatidylcholine-specific phospholipase C or trypsin, indicating a relatively firm attachment to the membrane bilayer. However, whole bile or taurocholate efficiently released apoA-1 at low concentrations that did not solubilize the transmembrane microvillar protein aminopeptidase N. Based on these findings and the well known role played by apoA-1 in extrahepatic cellular cholesterol removal and reverse cholesterol transport (RCT), we propose that brush border-deposited apoA-1 in the small intestine acts in TICE by mediating cholesterol efflux into the gut lumen.

  1. Refuting The Polemic Against the Extraocular Muscle Pulleys: Jampel and Shi’s Platygean View of Extraocular Muscle Mechanics

    PubMed Central

    Demer, Joseph L.

    2007-01-01

    Background Late in the 20th Century, it was recognized that connective tissue structures in the orbit influence the paths of the extraocular muscles, and constitute their functional origins. Targeted investigations of these connective tissue “pulleys” led to the formulation of the active pulley hypothesis, which proposes that pulling directions of the rectus extraocular muscles are actively controlled via connective tissues. Purpose This review rebuts a series of criticisms of the active pulley hypothesis published by Jampel, and Jampel and Shi, in which these authors have disputed the existence and function of the pulleys. Methods The current paper reviews published evidence for the existence of orbital pulleys, the active pulley hypothesis, and physiologic tests of the active pulley hypothesis. Magnetic resonance imaging in a living subject, and histological examination of a human cadaver directly illustrate the relationship of pulleys to extraocular muscles. Results Strong scientific evidence is cited that supports the existence of orbital pulleys, and their role in ocular motility. The criticisms of have ignored mathematical truisms and strong scientific evidence. Conclusions Actively controlled orbital pulleys play a fundamental role in ocular motility. Pulleys profoundly influence the neural commands required to control eye movements and binocular alignment. Familiarity with the anatomy and physiology of the pulleys is requisite for a rational approach to diagnosing and treating strabismus using emerging methods. Conversely, approaches that deny or ignore the pulleys risk the sorts of errors that arise in geography and navigation from incorrect assumptions such as those of a flat (“platygean”) earth. PMID:17022164

  2. Digital pulley reconstruction with expanded polytetrafluoroethylene (PTFE) membrane at the time of tenorrhaphy in an experimental animal model.

    PubMed

    Semer, N B; Bartle, B K; Telepun, G M; Goldberg, N H

    1992-05-01

    Digital pulley reconstruction with a synthetic material, PTFE membrane, was compared with suture repair of the native A3 pulley at the time of tenorrhaphy in the chicken model. The surgically treated foot was immobilized in flexion for either 28 or 35 days and then allowed full ambulation for periods of up to 42 days postoperatively. At sacrifice digits underwent range-of-motion testing, and the pulley and tenorrhaphy sites were explored. No disruptions were noted in the reconstructed PTFE pulleys. The number of tenorrhaphy disruptions was similar between the PTFE pulley group (11%) and the suture repair of the native pulley group (14%). No decrease in range of motion was demonstrated in the PTFE pulley digits, and no deleterious effect of increasing immobilization time (35 days versus 28 days) was noted. The results indicate that this synthetic pulley did not interfere with normal tendon healing processes. PTFE membrane may prove to be a promising reconstructive alternative when the native pulley is irreparably damaged.

  3. "Suture fixation of the fingers": an effective method for positioning burned and contracted fingers using a pulley system as a guide.

    PubMed

    Mohammadi, Ali Akbar; Bakhshaeekia, Alireza

    2011-03-01

    Preserving function of the hand is the aim of treatment in burned hands; appropriate splinting is one of the important measures during acute and chronic treatment. We introduce an effective safe method for positioning of fingers without violating the joints; In this method before performing skin graft for palmar finger burn or contracture release we suture tip of finger with silk 2-0 and fix it to dorsum of hand while extending the finger and for preventing slipping we insert some pulley like circles tied with silk 2-0 fixing over dorsum of mid phalanx. Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.

  4. S100A1 promotes action potential-initiated calcium release flux and force production in skeletal muscle.

    PubMed

    Prosser, Benjamin L; Hernández-Ochoa, Erick O; Lovering, Richard M; Andronache, Zoita; Zimmer, Danna B; Melzer, Werner; Schneider, Martin F

    2010-11-01

    The role of S100A1 in skeletal muscle is just beginning to be elucidated. We have previously shown that skeletal muscle fibers from S100A1 knockout (KO) mice exhibit decreased action potential (AP)-evoked Ca(2+) transients, and that S100A1 binds competitively with calmodulin to a canonical S100 binding sequence within the calmodulin-binding domain of the skeletal muscle ryanodine receptor. Using voltage clamped fibers, we found that Ca(2+) release was suppressed at all test membrane potentials in S100A1(-/-) fibers. Here we examine the role of S100A1 during physiological AP-induced muscle activity, using an integrative approach spanning AP propagation to muscle force production. With the voltage-sensitive indicator di-8-aminonaphthylethenylpyridinium, we first demonstrate that the AP waveform is not altered in flexor digitorum brevis muscle fibers isolated from S100A1 KO mice. We then use a model for myoplasmic Ca(2+) binding and transport processes to calculate sarcoplasmic reticulum Ca(2+) release flux initiated by APs and demonstrate decreased release flux and greater inactivation of flux in KO fibers. Using in vivo stimulation of tibialis anterior muscles in anesthetized mice, we show that the maximal isometric force response to twitch and tetanic stimulation is decreased in S100A1(-/-) muscles. KO muscles also fatigue more rapidly upon repetitive stimulation than those of wild-type counterparts. We additionally show that fiber diameter, type, and expression of key excitation-contraction coupling proteins are unchanged in S100A1 KO muscle. We conclude that the absence of S100A1 suppresses physiological AP-induced Ca(2+) release flux, resulting in impaired contractile activation and force production in skeletal muscle.

  5. Computer aided quantification of pathological features for flexor tendon pulleys on microscopic images.

    PubMed

    Liu, Yung-Chun; Chen, Hsin-Chen; Shih, Hui-Hsuan; Yang, Tai-Hua; Yang, Hsiao-Bai; Yang, Dee-Shan; Su, Fong-Chin; Sun, Yung-Nien

    2013-01-01

    Quantifying the pathological features of flexor tendon pulleys is essential for grading the trigger finger since it provides clinicians with objective evidence derived from microscopic images. Although manual grading is time consuming and dependent on the observer experience, there is a lack of image processing methods for automatically extracting pulley pathological features. In this paper, we design and develop a color-based image segmentation system to extract the color and shape features from pulley microscopic images. Two parameters which are the size ratio of abnormal tissue regions and the number ratio of abnormal nuclei are estimated as the pathological progression indices. The automatic quantification results show clear discrimination among different levels of diseased pulley specimens which are prone to misjudgments for human visual inspection. The proposed system provides a reliable and automatic way to obtain pathological parameters instead of manual evaluation which is with intra- and interoperator variability. Experiments with 290 microscopic images from 29 pulley specimens show good correspondence with pathologist expectations. Hence, the proposed system has great potential for assisting clinical experts in routine histopathological examinations.

  6. A2 and A4 flexor pulley biomechanical analysis: comparison among gender and digit.

    PubMed

    Mallo, Gregory Charles; Sless, Yury; Hurst, Lawrence C; Wilson, Kevin

    2008-03-01

    Rock climbing has become increasingly more popular in the USA over the past two decades. Accordingly, with increased participation comes an increase in climbing-related injuries. Rooks et al noted that three-quarters of elite and recreational climbers will suffer upper extremity injuries, approximately 60% involving the hand or wrist and 40% divided evenly between the shoulder and elbow. Most of these injures will be strains, microtrauma, and tendonitis; however, 30-50% represent trauma to the proximal interphalangeal region. The purpose of this study was to investigate the biomechanical properties of the A2 and A4 pulley and compare biomechanical properties among gender and digit. A specially designed materials testing machine, shown in the included figure, measured maximum breaking load, displacement and stiffness of the A2 and A4 pulleys of ten cadaveric hands using an S hook to apply a steady force until complete pulley rupture. The A2 and A4 biomechanical properties of breaking load, displacement, and stiffness did not significantly differ among the index, middle, ring, and little fingers. Additionally, there was no significant difference in A2 or A4 pulley biomechanics between male and female specimens. The A2 and A4 pulleys among differing digits and genders have similar biomechanical properties in regards to maximum breaking load, displacement, and stiffness.

  7. Carbon monoxide-releasing molecule-A1 (CORM-A1) improves clinical signs of experimental autoimmune uveoretinitis (EAU) in rats.

    PubMed

    Fagone, Paolo; Mangano, Katia; Mammana, Santa; Cavalli, Eugenio; Di Marco, Roberto; Barcellona, Maria Luisa; Salvatorelli, Lucia; Magro, Gaetano; Nicoletti, Ferdinando

    2015-04-01

    Uveitis is a sight-threatening inflammatory disease of the eye which represents the third leading cause of blindness in the developed countries. The conventional pharmacological treatment includes corticosteroids and immunosuppressive agents, which are limited by their side effects. New therapeutic strategies are thus strongly needed. Exogenously-administered carbon monoxide (CO) may represent an effective treatment for conditions characterized by a dysregulated inflammatory response. Carbon monoxide-releasing molecules (CORMs) are a novel group of compounds capable of carrying and liberating controlled quantities of CO. Among CORMs, CORM-A1 represents the first example of water soluble CO releaser. We show here that CORM-A1 under a late prophylactic regime is able to significantly ameliorate the natural course of experimental autoimmune uveoretinitis, a rodent model of immunoinflammatory posterior uveitis. The present study strongly supports the development of CORM-A1 as a potential new drug for treatment of patients with non-infectious posterior uveitis. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Quasi-stationary mechanics of elastic continua with bending stiffness wrapping on a pulley system

    NASA Astrophysics Data System (ADS)

    Kaczmarczyk, S.; Mirhadizadeh, S.

    2016-05-01

    In many engineering applications elastic continua such as ropes and belts often are subject to bending when they pass over pulleys / sheaves. In this paper the quasi-stationary mechanics of a cable-pulley system is studied. The cable is modelled as a moving Euler- Bernoulli beam. The distribution of tension is non-uniform along its span and due to the bending stiffness the contact points at the pulley-beam boundaries are not unknown. The system is described by a set of nonlinear ordinary differential equations with undetermined boundary conditions. The resulting nonlinear Boundary Value Problem (BVP) with unknown boundaries is solved by converting the problem into the ‘standard’ form defined over a fixed interval. Numerical results obtained for a range of typical configurations with relevant boundary conditions applied demonstrate that due to the effects of bending stiffness the angels of wrap are reduced and the span tensions are increased.

  9. The Durability of Conceptual Change in Learning the Concept of Weight in the Case of a Pulley in Balance

    ERIC Educational Resources Information Center

    Hakkarainen, Olavi; Ahtee, Maija

    2007-01-01

    This study concerns the question of how teachers can help pupils to perceive the concept of weight (gravitation). Fifth and ninth graders were asked in a paper-and-pencil test to compare the weight of two objects suspended in a pulley-in-balance half a year after the learning intervention consisting of three successive pulley-in-balance…

  10. The Durability of Conceptual Change in Learning the Concept of Weight in the Case of a Pulley in Balance

    ERIC Educational Resources Information Center

    Hakkarainen, Olavi; Ahtee, Maija

    2007-01-01

    This study concerns the question of how teachers can help pupils to perceive the concept of weight (gravitation). Fifth and ninth graders were asked in a paper-and-pencil test to compare the weight of two objects suspended in a pulley-in-balance half a year after the learning intervention consisting of three successive pulley-in-balance…

  11. Modulation of ischemia-evoked release of excitatory and inhibitory amino acids by adenosine A1 receptor agonist.

    PubMed

    Goda, H; Ooboshi, H; Nakane, H; Ibayashi, S; Sadoshima, S; Fujishima, M

    1998-09-18

    Adenosine has been reported to have beneficial effects against ischemic brain damage, although the mechanisms are not fully clarified. To examine the role of adenosine on the ischemia-evoked release of neurotransmitters, we applied a highly selective agonist for adenosine A1 receptor, 2-chloro-N6-cyclopentyladenosine (CCPA), into the ischemic brain using in vivo brain dialysis, which directly delivered the agonist to the local brain area. Concentrations of extracellular amino acids (glutamate, aspartate, gamma-aminobutyric acid (GABA) and taurine) and regional blood flow in the striatum of spontaneously hypertensive rats (SHRs) were monitored during cerebral ischemia elicited by bilateral carotid artery occlusion for 40 min and recirculation. Striatal blood flow and basal levels of amino acids were not affected by direct perfusion of CCPA (10 microM or 100 microM). During ischemia, concentrations of glutamate, aspartate, GABA and taurine increased up to 37-, 30-, 96- and 31-fold, respectively, when vehicle alone was administered. Administration of CCPA did not affect the changes in regional blood flow during ischemia and reperfusion. Perfusion of CCPA (100 microM), however, significantly attenuated the ischemia-evoked release of aspartate (by 70%) and glutamate (by 73%). The ischemia-induced increase of GABA tended to be decreased by CCPA, although it was not statistically significant. In contrast, both low and high concentrations of CCPA had little effect on the release of taurine during ischemia. These results suggest that stimulation of adenosine A1 receptors selectively attenuated the ischemia-evoked release of excitatory amino acids, but not of inhibitory amino acids without affecting blood flow. This modulation of the release of amino acids by adenosine A1 receptor agonists may play a protective role against ischemic neuronal damage.

  12. Friction between finger flexor tendons and the pulley system in the crimp grip position.

    PubMed

    Moor, Beat K; Nagy, Ladislav; Snedeker, Jess G; Schweizer, Andreas

    2009-01-01

    Disruption of the finger flexor tendon pulleys are the most often occurring injury in rock climbers due to bowstringing of tendons during crimp grip position. The aim of this study was to quantify friction between the flexor tendons and pulleys and the influence of high load and speed of movement as a potential factor of pulley disruption. Friction between the flexor tendons and pulleys of eight human cadaver fingers was indirectly determined using an isokinetic movement device. During flexion and extension movement with rotational speed from 30 to 210 deg/s in the proximal interphalangeal joint and with load from 20 to 100 N to the flexor tendons the flexion force at the tip of the finger was measured. With 40 N loaded flexor tendons the force at the fingertip was 14.5 N (SD1.5) during extension and 12.6N (SD1.3) during flexion movement. Corresponding force difference of 12.9% and 3.77 N (SD0.6) force of friction can be calculated. Friction peaked at 85.8 degrees (SD2.05) of flexion of the proximal interphalangeal joint. Different speed of motion and load to the flexor tendons did not influence force difference other than linear. Considerable friction between flexor tendons and pulleys is apparent and therefore may have an influence on pulley injuries. Particularly during the crimp grip position where the proximal interphalangeal joint is flexed about 90 degrees shows the greatest amount of friction. However there was no change of friction during high speed motion and no other than linear increase during high load.

  13. Role of muscle pulleys in producing eye position-dependence in the angular vestibuloocular reflex: a model-based study

    NASA Technical Reports Server (NTRS)

    Thurtell, M. J.; Kunin, M.; Raphan, T.; Wall, C. C. (Principal Investigator)

    2000-01-01

    It is well established that the head and eye velocity axes do not always align during compensatory vestibular slow phases. It has been shown that the eye velocity axis systematically tilts away from the head velocity axis in a manner that is dependent on eye-in-head position. The mechanisms responsible for producing these axis tilts are unclear. In this model-based study, we aimed to determine whether muscle pulleys could be involved in bringing about these phenomena. The model presented incorporates semicircular canals, central vestibular pathways, and an ocular motor plant with pulleys. The pulleys were modeled so that they brought about a rotation of the torque axes of the extraocular muscles that was a fraction of the angle of eye deviation from primary position. The degree to which the pulleys rotated the torque axes was altered by means of a pulley coefficient. Model input was head velocity and initial eye position data from passive and active yaw head impulses with fixation at 0 degrees, 20 degrees up and 20 degrees down, obtained from a previous experiment. The optimal pulley coefficient required to fit the data was determined by calculating the mean square error between data and model predictions of torsional eye velocity. For active head impulses, the optimal pulley coefficient varied considerably between subjects. The median optimal pulley coefficient was found to be 0.5, the pulley coefficient required for producing saccades that perfectly obey Listing's law when using a two-dimensional saccadic pulse signal. The model predicted the direction of the axis tilts observed in response to passive head impulses from 50 ms after onset. During passive head impulses, the median optimal pulley coefficient was found to be 0.21, when roll gain was fixed at 0.7. The model did not accurately predict the alignment of the eye and head velocity axes that was observed early in the response to passive head impulses. We found that this alignment could be well predicted if

  14. Role of muscle pulleys in producing eye position-dependence in the angular vestibuloocular reflex: a model-based study

    NASA Technical Reports Server (NTRS)

    Thurtell, M. J.; Kunin, M.; Raphan, T.; Wall, C. C. (Principal Investigator)

    2000-01-01

    It is well established that the head and eye velocity axes do not always align during compensatory vestibular slow phases. It has been shown that the eye velocity axis systematically tilts away from the head velocity axis in a manner that is dependent on eye-in-head position. The mechanisms responsible for producing these axis tilts are unclear. In this model-based study, we aimed to determine whether muscle pulleys could be involved in bringing about these phenomena. The model presented incorporates semicircular canals, central vestibular pathways, and an ocular motor plant with pulleys. The pulleys were modeled so that they brought about a rotation of the torque axes of the extraocular muscles that was a fraction of the angle of eye deviation from primary position. The degree to which the pulleys rotated the torque axes was altered by means of a pulley coefficient. Model input was head velocity and initial eye position data from passive and active yaw head impulses with fixation at 0 degrees, 20 degrees up and 20 degrees down, obtained from a previous experiment. The optimal pulley coefficient required to fit the data was determined by calculating the mean square error between data and model predictions of torsional eye velocity. For active head impulses, the optimal pulley coefficient varied considerably between subjects. The median optimal pulley coefficient was found to be 0.5, the pulley coefficient required for producing saccades that perfectly obey Listing's law when using a two-dimensional saccadic pulse signal. The model predicted the direction of the axis tilts observed in response to passive head impulses from 50 ms after onset. During passive head impulses, the median optimal pulley coefficient was found to be 0.21, when roll gain was fixed at 0.7. The model did not accurately predict the alignment of the eye and head velocity axes that was observed early in the response to passive head impulses. We found that this alignment could be well predicted if

  15. The perfect storm: Match-mismatch of bio-physical events drives larval reef fish connectivity between Pulley Ridge mesophotic reef and the Florida Keys

    NASA Astrophysics Data System (ADS)

    Vaz, Ana C.; Paris, Claire B.; Olascoaga, M. Josefina; Kourafalou, Villy H.; Kang, Heesook; Reed, John K.

    2016-08-01

    Mesophotic coral reef ecosystems are remote from coastal stressors, but are still vulnerable to over-exploitation, and remain mostly unprotected. They may be the key to coral reefs resilience, yet little is known about the pattern of larval subsidies from deeper to shallower coral reef habitats. Here we use a biophysical modeling approach to test the hypothesis that fishes from mesophotic coral reef ecosystems may replenish shallow reef populations. We aim at identifying the spatio-temporal patterns and underlying mechanisms of larval connections between Pulley Ridge, a mesophotic reef in the Gulf of Mexico hosting of a variety of shallow-water tropical fishes, and the Florida Keys reefs. A new three-dimensional (3D) polygon habitat module is developed for the open-source Connectivity Modeling System to simulate larval movement behavior of the bicolor damselfish, Stegastes partitus, in a realistic 3D representation of the coral reef habitat. Biological traits such as spawning periodicity, mortality, and vertical migration are also incorporated in the model. Virtual damselfish larvae are released daily from the Pulley Ridge at 80 m depth over 60 lunar spawning cycles and tracked until settlement within a fine resolution (~900 m) hydrodynamic model of the region. Such probabilistic simulations reveal mesophotic-shallow connections with large, yet sporadic pulses of larvae settling in the Florida Keys. Modal and spectral analyses on the spawning time of successful larvae, and on the position of the Florida Current front with respect to Pulley Ridge, demonstrate that specific physical-biological interactions modulate these "perfect storm" events. Indeed, the co-occurrence of (1) peak spawning with frontal features, and (2) cyclonic eddies with ontogenetic vertical migration, contribute to high settlement in the Florida Keys. This study demonstrates that mesophotic coral reef ecosystems can also serve as refugia for coral reef fish and suggests that they have a critical

  16. 5. Detail, west side, view to northeast, showing chain/pulley relationship ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Detail, west side, view to northeast, showing chain/pulley relationship and catwalk of top of plank walls. - Charlestown Navy Yard, Marine Railway, Between Piers 2 & 3, on Charlestown Waterfront at west end of Navy Yard, Boston, Suffolk County, MA

  17. A Mixed Model for Real-Time, Interactive Simulation of a Cable Passing Through Several Pulleys

    SciTech Connect

    Garcia-Fernandez, Ignacio; Pla-Castells, Marta; Martinez-Dura, Rafael J.

    2007-09-06

    A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

  18. Disruption of the finger flexor pulley system in elite rock climbers.

    PubMed

    Gabl, M; Rangger, C; Lutz, M; Fink, C; Rudisch, A; Pechlaner, S

    1998-01-01

    We treated 13 elite rock climbers for isolated disruptions of the pulleys of the long fingers. Diagnosis and treatment were based on the clinical finding of bow-stringing, which was confirmed by magnetic resonance imaging. Eight patients had bowstringing indicating incomplete disruption of the major pulley A2 and were treated nonoperatively (group A). Five patients showed bowstringing indicating complete disruption of the pulley A2. After failed nonoperative treatment, the pulleys were reconstructed (group B). The mechanism of injury and clinical and subjective results were evaluated. At a 31-month follow-up (range, 18 to 43 months), loss of extension in the proximal interphalangeal joint measured 5.6 degrees (range, 0 degree to 10 degrees) in group A and 4 degrees (range, 0 degree to 10 degrees) in group B. Circumference of the finger section was increased 4.2 mm in group A (range, 0 to 10 mm) and 4.8 mm in group B (range, 0 to 10 mm). Grip strength decreased 20 N in group A (range, 10 to 50 N) and 12 N in group B (range, 10 to 30 N). Four patients in group A and one in group B had bowstringing at clinical evaluation. On follow-up magnetic resonance images, bowstringing remained unchanged in group A but was reduced in all patients in group B. Good subjective results were seen in both groups.

  19. Hybrid modeling for dynamic analysis of cable-pulley systems with time-varying length cable and its application

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Qi, Zhaohui; Wang, Gang

    2017-10-01

    The dynamic analysis of cable-pulley systems is investigated in this paper, where the time-varying length characteristic of the cable as well as the coupling motion between the cable and the pulleys are considered. The dynamic model for cable-pulley systems are presented based on the principle of virtual power. Firstly, the cubic spline interpolation is adopted for modeling the flexible cable elements and the virtual 1powers of tensile strain, inertia and gravity forces on the cable are formulated. Then, the coupled motions between the cable and the movable or fixed pulley are described by the input and output contact points, based on the no-slip assumption and the spatial description. The virtual powers of inertia, gravity and applied forces on the contact segment of the cable, the movable and fixed pulleys are formulated. In particular, the internal node degrees of freedom of spline cable elements are reduced, which results in that only the independent description parameters of the nodes connected to the pulleys are included in the final governing dynamic equations. At last, two cable-pulley lifting mechanisms are considered as demonstrative application examples where the vibration of the lifting process is investigated. The comparison with ADAMS models is given to prove the validity of the proposed method.

  20. Fetal development of the pulley for muscle insertion tendons: A review and new findings related to the tensor tympani tendon.

    PubMed

    Rodríguez-Vázquez, Jose Francisco; Honkura, Yohei; Katori, Yukio; Murakami, Gen; Abe, Hiroshi

    2017-01-01

    The existence of hard tissue pulleys that act to change the direction of a muscle insertion tendon is well known in the human body. These include (1) the trochlea for the extraocular obliquus superior muscle, (2) the pterygoid hamulus for the tensor veli palatini muscle, (3) the deep sulcus on the plantar aspect of the cuboid bone for the peroneus longus tendon, (4) the lesser sciatic notch for the obturator internus muscle, and (5) the bony trochleariformis process for the tensor tympani muscle tendon. In addition, (6) the stapedius muscle tendon shows a lesser or greater angulation at the pyramidal eminence of the temporal bone. Our recent studies have shown that the development of pulleys Nos. 1 and 2 can be explained by a change in the topographical relationship between the pulley and the tendon, that of pulley No. 3 by the rapidly growing calcaneus pushing the tendon, and that of pulley No. 4 by migration of the insertion along the sciatic nerve and gluteus medius tendon. Therefore, in Nos. 1-4, an initially direct tendon curves secondarily and obtains an attachment to the pulley. In case No. 6, the terminal part of the stapedius tendon originates secondarily from the interzone mesenchymal tissue of the incudostapedial joint. In the case of pulley No. 5, we newly demonstrated that its initial phase of development was similar to No. 6, but the tensor tympani tendon achieved a right-angled turn under guidance by a specific fibrous tissue and it migrated along the growing malleus manubrium.

  1. Assessing the Diversity of Halimeda spp. on Pulley Ridge Mesophotic Reefs

    NASA Astrophysics Data System (ADS)

    Luzader, R. K.; Baco-Taylor, A.

    2016-02-01

    The Florida reef system contains an array of organisms that contribute to the development of the reef structure. These include calcifying green macroalgae of the genus Halimeda, which provides important ecosystem services by stabilizing the reefs through calcification. Halimeda is one of several groups of shallow water reef taxa with a depth range that extends into the mesophotic zone. It has been hypothesized the mesophotic reefs may serve as refugia for shallow water taxa impacted by climate change and other anthropogenic stressors. To test this hypothesis, in 2012-2015, the mesophotic reefs of Pulley Ridge and Dry Tortugas were sampled to assess genetic connectivity to the shallow water reefs of the Florida Keys. A diverse array of Halimeda species were represented on Pulley Ridge. Halimeda species are known to be difficult to identify and delineate morphologically and the taxonomy of Halimeda species has been revised several times based on molecular data. Thus, before connectivity of mesophotic Halimeda to shallow populations can be assessed, our first goal is to determine whether there is overlap of any of the Halimeda species between the mesophotic and shallow reefs, and then to determine if any of the species are present in sufficient abundance for population genetics. We sequenced portions of two chloroplast genes commonly used for algal phylogenetics and barcoding, tufA and rbcL, for at least 5 individuals of each morphotype collected on Dry Tortugas and the Pulley Ridge mesophotic reefs. Preliminary results suggest that Halimeda tuna, the species previously reported as the dominant Halimeda species on Pulley Ridge, was relatively uncommon. Morphological results and comparison of initial genetic results to sequences in GenBank suggest that H. goreaui is abundant at the Dry Tortugas site and H. fragilis, H. copiosa and H. discoidea are common on Pulley Ridge, indicating greater Halimeda diversity in the mesophotic reef system than previously documented.

  2. Pulley Reconstruction As Part of the Surgical Treatment for de Quervain Disease: Surgical Technique with Medium-Term Results

    PubMed Central

    van der Wijk, Jacobien; Goubau, Jean F.; Mermuys, Koen; van Hoonacker, Petrus; Vanmierlo, Bert; Kerckhove, Diederick; Berghs, Bart

    2015-01-01

    Background Simple decompression of the first extensor compartment is commonly used for treating de Quervain disease, with the possible complication of subluxation of the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) over the radial styloid. To prevent this painful subluxation of the tendons, several methods of reconstructing the pulley have been proposed. Questions/Purposes The purpose of our study was to evaluate a new technique for reconstructing the first extensor compartment following a release for de Quervain disease. Patients and Methods A retrospective study (mean length 40.4 months) was performed in 45 patients. The outcome assessment involved two different questionnaires and ultrasound evaluation of any tendon subluxation. Results None of the patients required reoperation for tendon instability or incomplete decompression of the first extensor compartment. Two patients experienced clicking around the radial styloid after surgery. This was not related to the amount of volar migration of the tendons. Conclusions We believe the reconstruction proposed here is an effective method of preventing painful subluxation of the APL and EPB following a release of the first extensor compartment. PMID:26261747

  3. Pulley Reconstruction As Part of the Surgical Treatment for de Quervain Disease: Surgical Technique with Medium-Term Results.

    PubMed

    van der Wijk, Jacobien; Goubau, Jean F; Mermuys, Koen; van Hoonacker, Petrus; Vanmierlo, Bert; Kerckhove, Diederick; Berghs, Bart

    2015-08-01

    Background Simple decompression of the first extensor compartment is commonly used for treating de Quervain disease, with the possible complication of subluxation of the tendons of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) over the radial styloid. To prevent this painful subluxation of the tendons, several methods of reconstructing the pulley have been proposed. Questions/Purposes The purpose of our study was to evaluate a new technique for reconstructing the first extensor compartment following a release for de Quervain disease. Patients and Methods A retrospective study (mean length 40.4 months) was performed in 45 patients. The outcome assessment involved two different questionnaires and ultrasound evaluation of any tendon subluxation. Results None of the patients required reoperation for tendon instability or incomplete decompression of the first extensor compartment. Two patients experienced clicking around the radial styloid after surgery. This was not related to the amount of volar migration of the tendons. Conclusions We believe the reconstruction proposed here is an effective method of preventing painful subluxation of the APL and EPB following a release of the first extensor compartment.

  4. Arthroscopic Changes of the Biceps Pulley in Rotator Cuff Tear and Its Clinical Significance in Relation to Treatment.

    PubMed

    Choi, Chang Hyuk; Kim, Se Sik; Kim, Seok Jun; Lee, Ju Hwan

    2015-09-01

    In the case of rotator cuff tears, the biceps pulley can be stressed by the unstable biceps tendon, and this can subsequently affect the stability of the subscapularis tendon. Therefore, it is important to distinguish between normal variations and lesions of the biceps pulley that affect anterosuperior lesions in cases of rotator cuff tears. From January 2002 through November 2010, we observed biceps pulley and associated anterosuperior lesions in 589 of 634 cases (93%) of arthroscopic rotator cuff repair, including 72 cases (12.2%) of small tears, 219 cases (37.2%) of medium tears, 134 cases (22.8%) of large tears, and 164 cases (27.8%) of massive tears. We classified normal stretched biceps pulleys as type I, stretched biceps pulleys with mild changes as type II, those with a partial tear as type III, and torn pulleys as type IV. We were able to classify 589 cases of biceps pulleys as type I, II, III, or IV associated lesions in rotator cuff tears. Type I was seen in 91 cases (15.4%), type II in 216 cases (36.7%), type III in 157 cases (26.7%), and type IV in 101 cases (17.1%); unidentified cases numbered 24 (4.1%). Nearly three-quarters, 73.3%, of the cases (432/589) had associated anterosuperior lesions, and combined treatment for the associated lesions was administered in 29.2% (172/589) of cases. Biceps pulley lesions with more than partial tears were identified in 48% of rotator cuff tear cases. The incidence and severity of pulley lesions were related to the rotator cuff tear size, the status of the long head of the biceps tendon and subscapularis tendon lesion, and the treatment methods.

  5. The perfect storm: match-mismatch of bio-physical events drives larval reef fish connectivity between Pulley Ridge and the Florida Keys

    NASA Astrophysics Data System (ADS)

    Vaz, A.; Paris, C. B.; Olascoaga, M. J.; Kourafalou, V.; Kang, H.

    2016-02-01

    Mesophotic reefs have been hypothesized to act as a refugia, by exporting larvae to more vulnerable shallow water reefs and potentially aiding the replenishment of disturbed populations. Despite the fundamental role of mesophotic reef for the recovery and conservation of shallow water reef ecosystems, the spatio-temporal extent of such connections is currently unresolved. Here we aim to explore the underlaying mechanisms of the connections between a mesophotic reef, the Pulley Ridge, and the shallow water Florida Keys reefs, by simulating the dispersal of the bicolor damselfish, Stegastes partitus. We use the Connectivity Modeling System (CMS) of the University of Miami, an open-source individual-based model, and present new biophysical modeling code to allow a realistic representation of 3-dimensional discreet coral reef habitats and investigate vertical connectivity. Virtual larvae are released and tracked within a fine resolution ( 900m) hydrodynamic model until their settlement. S. partitus biological traits such as spawning periodicity, mortality and vertical migration are also incorporated on the model. Probabilistic simulations indicate mesophotic-shallow connections, with larvae spawned at Pulley Ridge reaching the Florida Keys settlement grounds during sporadic settlement pulses. These "perfect storm" settlement events are modulated by the co-occurence of larval traits with physical processes, particularly by the interaction of ontogenetic vertical migration and the Florida Current fronts and cyclonic eddies. This demonstrates that mesophotic coral reef ecosystems can also serve as a refugia for coral reef fish and suggests that they could increase the resilience of their shallow counterpart.

  6. Carbon Monoxide Releasing Molecule-A1 (CORM-A1) Improves Neurogenesis: Increase of Neuronal Differentiation Yield by Preventing Cell Death.

    PubMed

    Almeida, Ana S; Soares, Nuno L; Vieira, Melissa; Gramsbergen, Jan Bert; Vieira, Helena L A

    2016-01-01

    Cerebral ischemia and neurodegenerative diseases lead to impairment or death of neurons in the central nervous system. Stem cell based therapies are promising strategies currently under investigation. Carbon monoxide (CO) is an endogenous product of heme degradation by heme oxygenase (HO) activity. Administration of CO at low concentrations produces several beneficial effects in distinct tissues, namely anti-apoptotic and anti-inflammatory. Herein the CO role on modulation of neuronal differentiation was assessed. Three different models with increasing complexity were used: human neuroblastoma SH-S5Y5 cell line, human teratocarcinoma NT2 cell line and organotypic hippocampal slice cultures (OHSC). Cell lines were differentiated into post-mitotic neurons by treatment with retinoic acid (RA) supplemented with CO-releasing molecule A1 (CORM-A1). CORM-A1 positively modulated neuronal differentiation, since it increased final neuronal production and enhanced the expression of specific neuronal genes: Nestin, Tuj1 and MAP2. Furthermore, during neuronal differentiation process, there was an increase in proliferative cell number (ki67 mRNA expressing cells) and a decrease in cell death (lower propidium iodide (PI) uptake, limitation of caspase-3 activation and higher Bcl-2 expressing cells). CO supplementation did not increase the expression of RA receptors. In the case of SH-S5Y5 model, small amounts of reactive oxygen species (ROS) generation emerges as important signaling molecules during CO-promoted neuronal differentiation. CO's improvement of neuronal differentiation yield was validated using OHSC as ex vivo model. CORM-A1 treatment of OHSC promoted higher levels of cells expressing the neuronal marker Tuj1. Still, CORM-A1 increased cell proliferation assessed by ki67 expression and also prevented cell death, which was followed by increased Bcl-2 expression, decreased levels of active caspase-3 and PI uptake. Likewise, ROS signaling emerged as key factors in CO

  7. Transdermal anaesthesia for percutaneous trigger finger release.

    PubMed

    Yiannakopoulos, Christos K; Ignatiadis, Ioannis A

    2006-01-01

    The purpose of this study was to evaluate the safety and efficiency of transdermal anaesthesia using eutectic mixture of lidocaine and prilocaine (EMLA) in patients undergoing percutaneous trigger finger release and to compare it with lidocaine infiltration. In this prospective, randomised study percutaneous release of the A1 annular pulley was performed to treat stenosing tenosynovitis (trigger finger syndrome) in 50 patients (50 fingers). The procedure was performed either under transdermal anaesthesia using EMLA applied transcutaneously 120 minutes prior to the operation (Group A, n = 25) or using local infiltration anaesthesia using lidocaine (Group B, n = 25). Pain experienced during administration of anaesthesia and during the operation was assessed using a 10-point Visual Analogue Pain Scale (VAPS), while all patients rated the effectiveness of anaesthesia with a 5-point scale. There were no significant differences between the two groups in the VAPS during the operation (1.33 +/- 0.52 versus 1.59 +/- 0.87) and the satisfaction scores (4.6 +/- 0.2 versus 4.4 +/- 0.3). The VAPS score during the administration of anaesthesia was statistically significantly less in the EMLA group (0 versus 5.96 +/- 2.41). All patients were satisfied with the final result of the operation. Percutaneous trigger finger release can be performed as an office procedure with the use of EMLA avoiding the use of injectable local infiltration anaesthesia.

  8. Microcontroller Based Proportional Derivative Plus Conditional Integral Controller for Electro-Mechanical Dual Acting Pulley Continuously Variable Transmission Ratio Control

    NASA Astrophysics Data System (ADS)

    Budianto, A.; Tawi, K. B.; Hussein, M.; Supriyo, B.; Ariyono, S.; Che Kob, M. S.; Ezlamy Zulkifli, Mohd; K, Khairuldean A.; Daraoh, Aishah

    2012-09-01

    Electro-Mechanical Dual Acting Pulley (EMDAP) Continuously Variable Transmission (CVT) is a transmission utilized by electro-mechanical actuated system. It has a potential to reduce energy consumption because it only needs power during changing CVT ratio and no power is needed to maintain CVT ratio due to self lock mechanism design. This paper proposed simple proportional derivative plus conditional integral (PDCI) controller to control EMDAP CVT ratio which can be simply implemented on a microcontroller. This proposed controller used Astrom-Hagglund method and Ziegler-Nichols formula to tune PDCI gain. The Proportional Derivative controller is directly activated from the start but Integral controller is only activated when the error value reaches error value setting point. Simulation using Matlab/Simulink software was conducted to evaluate PDCI system performance. The simulation results showed PDCI controller has ability to perform maximum overshoot 0.1%, 0.001 steady state error and 0.5s settling time. For clamping condition, settling time is about 11.46s during changing ratio from 2.0 to 0.7, while for release condition, settling time is about 8.33s during changing ratio from 0.7 to 2.0.

  9. The surprising dynamics of a chain on a pulley: lift off and snapping

    PubMed Central

    Audoly, Basile

    2016-01-01

    The motion of weights attached to a chain or string moving on a frictionless pulley is a classic problem of introductory physics used to understand the relationship between force and acceleration. Here, we consider the dynamics of the chain when one of the weights is removed and, thus, one end is pulled with constant acceleration. This simple change has dramatic consequences for the ensuing motion: at a finite time, the chain ‘lifts off’ from the pulley, and the free end subsequently accelerates faster than the end that is pulled. Eventually, the chain undergoes a dramatic reversal of curvature reminiscent of the crack or snap, of a whip. We combine experiments, numerical simulations and theoretical arguments to explain key aspects of this dynamical problem. PMID:27436987

  10. The surprising dynamics of a chain on a pulley: lift off and snapping.

    PubMed

    Brun, P-T; Audoly, Basile; Goriely, Alain; Vella, Dominic

    2016-06-01

    The motion of weights attached to a chain or string moving on a frictionless pulley is a classic problem of introductory physics used to understand the relationship between force and acceleration. Here, we consider the dynamics of the chain when one of the weights is removed and, thus, one end is pulled with constant acceleration. This simple change has dramatic consequences for the ensuing motion: at a finite time, the chain 'lifts off' from the pulley, and the free end subsequently accelerates faster than the end that is pulled. Eventually, the chain undergoes a dramatic reversal of curvature reminiscent of the crack or snap, of a whip. We combine experiments, numerical simulations and theoretical arguments to explain key aspects of this dynamical problem.

  11. The surprising dynamics of a chain on a pulley: lift off and snapping

    NASA Astrophysics Data System (ADS)

    Brun, P.-T.; Audoly, Basile; Goriely, Alain; Vella, Dominic

    2016-06-01

    The motion of weights attached to a chain or string moving on a frictionless pulley is a classic problem of introductory physics used to understand the relationship between force and acceleration. Here, we consider the dynamics of the chain when one of the weights is removed and, thus, one end is pulled with constant acceleration. This simple change has dramatic consequences for the ensuing motion: at a finite time, the chain `lifts off' from the pulley, and the free end subsequently accelerates faster than the end that is pulled. Eventually, the chain undergoes a dramatic reversal of curvature reminiscent of the crack or snap, of a whip. We combine experiments, numerical simulations and theoretical arguments to explain key aspects of this dynamical problem.

  12. The Effect of Friction in Pulleys on the Tension in Cables and Strings

    NASA Astrophysics Data System (ADS)

    Martell, Eric C.; Martell, Verda Beth

    2013-02-01

    Atwood's machine is used in countless introductory physics classes as an illustration of Newton's second law. Initially, the analysis is performed assuming the pulley and string are massless and the axle is frictionless. Although the mass of the pulley is often included when the problem is revisited later in the context of rotational dynamics, the mass of the string and the friction associated with the axle are less frequently discussed. Two questions then arise: 1) If we are ignoring these effects, how realistic is our model? and 2) How can we determine when or if we need to incorporate these effects in order to make our model match up with reality? These questions are connected to fundamental issues faced by physics teachers, namely the frustration students sometimes feel when they do not see how they can use the results of the problems they have been working on and how we can help our students develop effective models for physical systems.

  13. Design and implementation of fluidic micro-pulleys for flow control on centrifugal microfluidic platforms

    PubMed Central

    Soroori, Salar; Kulinsky, Lawrence; Kido, Horacio; Madou, Marc

    2013-01-01

    Microfluidic discs have been employed in a variety of applications for chemical analyses and biological diagnostics. These platforms offer a sophisticated fluidic toolbox, necessary to perform processes that involve sample preparation, purification, analysis, and detection. However, one of the weaknesses of such systems is the uni-directional movement of fluid from the disc center to its periphery due to the uni-directionality of the propelling centrifugal force. Here we demonstrate a mechanism for fluid movement from the periphery of a hydrophobic disc toward its center that does not rely on the energy supplied by any peripheral equipment. This method utilizes a ventless fluidic network that connects a column of working fluid to a sample fluid. As the working fluid is pushed by the centrifugal force to move toward the periphery of the disc, the sample fluid is pulled up toward the center of the disc analogous to a physical pulley where two weights are connected by a rope passed through a block. The ventless network is analogous to the rope in the pulley. As the working fluid descends, it creates a negative pressure that pulls the sample fluid up. The sample and working fluids do not come into direct contact and it allows the freedom to select a working fluid with physical properties markedly different from those of the sample. This article provides a demonstration of the “micro-pulley” on a disc, discusses underlying physical phenomena, provides design guidelines for fabrication of micro-pulleys on discs, and outlines a vision for future micro-pulley applications. PMID:25328508

  14. The double-pulley technique for double-row rotator cuff repair.

    PubMed

    Arrigoni, Paolo; Brady, Paul C; Burkhart, Stephen S

    2007-06-01

    In an effort to maximize the area of footprint coverage, we developed the "double-pulley technique" for double-row rotator cuff repairs. Two suture anchors are inserted at the articular margin of the greater tuberosity (one anterior and one posterior). All 4 suture strands from each anchor are passed through a single medial point on the torn cuff. In this way, the 4 suture strands from the anteromedial anchor pass through 1 point in the cuff and the 4 strands from the posteromedial anchor pass through a different point in the cuff. A suture strand from 1 anchor is tied extracorporeally to a suture strand of the same color from the other anchor. The other ends of those 2 strands are then pulled, thereby delivering this extracorporeal knot into the joint and over the medial footprint. These 2 free suture strands are then tied together as a static knot. The procedure is repeated with the other sutures. This technique creates a double mattress suture medially, which compresses the intervening tendon bridge against its bone bed. We call this procedure the double-pulley technique because it uses the anchor eyelets as pulleys to deliver the extracorporeal knot into the shoulder. After the lateral row repair is performed, the rotator cuff footprint will be completely reconstituted.

  15. Endoscopic submucosal dissection with the pulley method for early-stage gastric cancer (with video).

    PubMed

    Li, Chung-Hsien; Chen, Peng-Jen; Chu, Heng-Cheng; Huang, Tien-Yu; Shih, Yu-Lueng; Chang, Wei-Kuo; Hsieh, Tsai-Yuan

    2011-01-01

    Using EMR techniques, physicians frequently remove tumors >15 mm by piecemeal resection, which is associated with an increased rate of disease recurrence and difficulty in histologically evaluating the specimen. Endoscopic submucosal dissection (ESD) of early-stage gastric cancer improves the rate of successful en bloc resection, but it is associated with more complications, such as bleeding and perforation, than conventional EMR. To describe a simple technique that uses the pulley method to facilitate ESD procedures in the excision of large early-stage gastric cancers. Case series. Tertiary medical center in Taiwan. Eleven patients with early-stage gastric cancers or adenomas >20 mm underwent ESD. The pulley method with standard clips and dental floss was used to provide traction to improve visualization of the dissection plane during ESD. Proportion with complete en bloc resection. En bloc resection of the lesion was achieved in 11 patients. No perforation or emergent surgery was noted. One endoscopist performed all procedures, and only 11 patients were studied in an uncontrolled manner. The pulley method seems to facilitate en bloc ESD of early-stage gastric cancers >20 mm. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  16. The influence of concentric and eccentric loading on the finger pulley system.

    PubMed

    Schöffl, I; Oppelt, K; Jüngert, J; Schweizer, A; Bayer, T; Neuhuber, W; Schöffl, V

    2009-09-18

    In this study we investigated the influence of the loading condition (concentric vs. eccentric loading) on the pulley system of the finger. For this purpose 39 cadaver finger (14 hands, 10 donors) were fixed into an isokinetic loading device. The forces in the flexor tendons and at the fingertip were recorded. In the concentric loading condition A2 and A4 ruptures as well as alternative events such as fracture of a phalanx or avulsion of the flexor tendons were almost equally distributed, whereas the A2 pulley rupture was the most common event (59%) in the eccentric loading condition and alternative events were rare (23.5%). The forces in the deep flexor tendon, the fingertip and in the pulleys were significantly lower in the eccentric loading condition. As the ruptures occurred at lower loads in the eccentric than in the concentric loading condition it can be concluded that friction may be an advantage for climbers, supporting the holding force of their flexor muscles but may also increase the susceptibility to injury.

  17. Integrated learning in practical machine element design course: a case study of V-pulley design

    NASA Astrophysics Data System (ADS)

    Tantrabandit, Manop

    2014-06-01

    To achieve an effective integrated learning in Machine Element Design course, it is of importance to bridge the basic knowledge and skills of element designs. The multiple core learning leads the pathway which consists of two main parts. The first part involves teaching documents of which the contents are number of V-groove formulae, standard of V-grooved pulleys, and parallel key dimension's formulae. The second part relates to the subjects that the students have studied prior to participating in this integrated learning course, namely Material Selection, Manufacturing Process, Applied Engineering Drawing, CAD (Computer Aided Design) animation software. Moreover, an intensive cooperation between a lecturer and students is another key factor to fulfill the success of integrated learning. Last but not least, the students need to share their knowledge within the group and among the other groups aiming to gain knowledge of and skills in 1) the application of CAD-software to build up manufacture part drawings, 2) assembly drawing, 3) simulation to verify the strength of loaded pulley by method of Finite Element Analysis (FEA), 4) the software to create animation of mounting and dismounting of a pulley to a shaft, and 5) an instruction manual. The end product of this integrated learning, as a result of the above 1 to 5 knowledge and skills obtained, the participating students can create an assembly derived from manufacture part drawings and a video presentation with bilingual (English-Thai) audio description of Vpulley with datum diameter of 250 mm, 4 grooves, and type of groove: SPA.

  18. The direct midlateral approach with lateral enlargement of the pulley system for repair of flexor tendons in fingers.

    PubMed

    Messina, A; Messina, J C

    1996-08-01

    The direct midlateral approach and the lateral enlarging procedure of the pulley system have been utilized in our service since 1972. The incision runs directly behind the neurovascular pedicle, which is left in the palmar skin flap of the anterior compartment of the finger, in order to ensure its blood supply and sensibility. The transverse digital lamina of Landsmeer's skin anchoring system and Cleland's ligament are preserved and are used to perform a lateral enlargement of the pulleys after tendon repair. The technique allows wide surgical exposure of the digital fibro-osseous tunnel, enlargement and reconstruction of the pulley system and tendon sheath, flexor tendon repair (using the technique of choice) and reduces postoperative impingement in zone 2.

  19. Situational restriction: using your physical exam to differentiate pulley abnormalities from other vertical deviations secondary to restrictive conditions.

    PubMed

    Rosenberg, Steven E; Shippman, Sara

    2011-01-01

    The description of the orbital pulley system has changed the way we understand eye movements and ocular motility disorders. The presence of abnormalities in the orbital pulley system can complicate the assessment of vertical restrictive conditions. The standard tests for restriction are reviewed. These include version and duction testing, assessing saccades, differential intraocular pressure measurements, forced duction testing, and forced generation testing. We introduce the concept of situational restriction and how to look for it during your physical exam. Situational restriction is a limitation of ocular rotation that is dependent on the path that is taken to try to arrive at a tertiary position of ocular rotation. Specifically, it shows noncommutative movement that breaks Listing's Law. The presence of situational restriction denotes that a pulley abnormality is present.

  20. Friction between human finger flexor tendons and pulleys at high loads.

    PubMed

    Schweizer, A; Frank, O; Ochsner, P E; Jacob, H A C

    2003-01-01

    A method was developed to indirectly measure friction between the flexor tendons and pulleys of the middle and ring finger in vivo. An isokinetic movement device to determine maximum force of wrist flexion, interphalangeal joint flexion (rolling in and out) and isolated proximal interphalangeal (PIP) joint flexion was built. Eccentric and concentric maximum force of these three different movements where gliding of the flexor tendon sheath was involved differently (least in wrist flexion) was measured and compared. Fifty-one hands in 26 male subjects were evaluated. The greatest difference between eccentric and concentric maximum force (29.9%) was found in flexion of the PIP joint. Differences in the rolling in and out movement (26.8%) and in wrist flexion (14.5%) were significantly smaller. The force of friction between flexor tendons and pulleys can be determined by the greater difference between eccentric and concentric maximum force provided by the same muscles in overcoming an external force during flexion of the interphalangeal joints and suggests the presence of a non-muscular force, such as friction. It constitutes of 9% of the eccentric flexion force in the PIP joint and therefore questions the low friction hypothesis at high loads. Copyright 2002 Elsevier Science Ltd.

  1. Anomalous Velocity Dependence of the Friction Coefficient of an Air Supported Pulley

    NASA Astrophysics Data System (ADS)

    Crismani, Matteo; Nauenberg, Michael

    2009-11-01

    A standard undergraduate lab exercise to verify Newton's law, F = ma, is to measure the acceleration a of a glider of mass m suspended on an air track. In our experiment the glider is accelerated by a thin tape attached to the glider at one end, and to a weight of mass M at the other end. The weight hangs vertically via a pulley over which the tape is suspended by air pressure. In the absence of friction, the force pulling the glider is F = (M m/(M + m)g, where g is the acceleration of gravity. To the accuracy provided by the fast electronic timers (accurate to 1/10000 second) used in our experiment to measure the velocity and the acceleration of the glider, we verified that the friction due to the air track can be neglected. But we found that this is not the case for the friction due to the air pulley which adds a component -v/T to the force F on the glider, where T is the friction coefficient. We have measured the dependence of this coefficient on v, and found an excellent analytic fit to our data. This fit deviates considerable from the conventional assumption that 1/T is a constant and/or depends linearly on v.

  2. Reconstruction of the digital flexor pulley system: a retrospective comparison of two methods of treatment.

    PubMed

    Arora, R; Fritz, D; Zimmermann, R; Lutz, M; Kamelger, F; Klauser, A S; Gabl, M

    2007-02-01

    The rare injury of closed rupture of the A2 and A3 flexor pulleys was treated using two non-encircling techniques of pulley reconstruction. Thirteen patients were treated with an extensor retinaculum graft (Group A). At a mean follow-up time of 48 months, the average PIP flexion was 97%, the power grip strength 96%, the pinch grip strength 100% and the thickening 94% of the uninjured side. Ten patients were treated with a free palmaris longus tendon grafts (Group B). At a mean follow-up time of 57 months, the average PIP flexion was 94%, the power grip strength 98%, the pinch grip strength 100% and the thickening 95% of the uninjured side. In both groups, finger extension was unrestricted. The Buck Gramcko score included 10 excellent, two good and one fair result in Group A and seven excellent, two good and one fair result in Group B. Both techniques proved beneficial. All climbers returned to their previous standard and all non-climbers regained full finger dexterity in their previous job.

  3. The inhibition of release by mGlu7 receptors is independent of the Ca2+ channel type but associated to GABAB and adenosine A1 receptors.

    PubMed

    Martín, Ricardo; Ladera, Carolina; Bartolomé-Martín, David; Torres, Magdalena; Sánchez-Prieto, José

    2008-09-01

    Neurotransmitter release is inhibited by G-protein coupled receptors (GPCRs) through signalling pathways that are negatively coupled to Ca2+ channels and adenylyl cyclase. Through Ca2+ imaging and immunocytochemistry, we have recently shown that adenosine A1, GABAB and the metabotropic glutamate type 7 receptors coexist in a subset of cerebrocortical nerve terminals. As these receptors inhibit glutamate release through common intracellular signalling pathways, their co-activation occluded each other responses. Here we have addressed whether the occlusion of receptor responses is restricted to the glutamate release mediated by N-type Ca2+ channels by analysing this process in nerve terminals from mice lacking the alpha1B subunit (Cav 2.2) of these channels. We found that glutamate release from cerebrocortical nerve terminals without these channels, in which release relies exclusively on P/Q type Ca2+ channels, is not modulated by mGlu7 receptors. Furthermore, there is no occlusion of the release inhibition by GABAB and adenosine A1. Hence, in the cerebrocortical preparation, these three receptors only appear to coexist in N-type channel containing nerve terminals. In contrast, in hippocampal nerve terminals lacking this subunit, where mGlu7 receptors modulate glutamate release via P/Q type channels, the occlusion of inhibitory responses by co-stimulation of adenosine A1, GABAB and mGlu7 receptors was observed. Thus, occlusion of the responses by the three GPCRs is independent of the Ca2+ channel type but rather, it is associated to functional mGlu7 receptors.

  4. The role of adenosine A1 and A2A receptors in the caffeine effect on MDMA-induced DA and 5-HT release in the mouse striatum.

    PubMed

    Górska, A M; Gołembiowska, K

    2015-04-01

    3,4-Methylenedioxymethamphetamine (MDMA, "ecstasy") popular as a designer drug is often used with caffeine to gain a stronger stimulant effect. MDMA induces 5-HT and DA release by interaction with monoamine transporters. Co-administration of caffeine and MDMA may aggravate MDMA-induced toxic effects on DA and 5-HT terminals. In the present study, we determined whether caffeine influences DA and 5-HT release induced by MDMA. We also tried to find out if adenosine A1 and A2A receptors play a role in the effect of caffeine by investigating the effect of the selective adenosine A1 and A2A receptor antagonists, DPCPX and KW 6002 on DA and 5-HT release induced by MDMA. Mice were treated with caffeine (10 mg/kg) and MDMA (20 or 40 mg/kg) alone or in combination. DA and 5-HT release in the mouse striatum was measured using in vivo microdialysis. Caffeine exacerbated the effect of MDMA on DA and 5-HT release. DPCPX or KW 6002 co-administered with MDMA had similar influence as caffeine, but KW 6002 was more potent than caffeine or DPCPX. To exclude the contribution of MAO inhibition by caffeine in the caffeine effect on MDMA-induced increase in DA and 5-HT, we also tested the effect of the nonxanthine adenosine receptor antagonist CGS 15943A lacking properties of MAO activity modification. Our findings indicate that adenosine A1 and A2A receptor blockade may account for the caffeine-induced exacerbation of the MDMA effect on DA and 5-HT release and may aggravate MDMA toxicity.

  5. The effect of partial excision of the A2 and A4 pulleys on the biomechanics of finger flexion.

    PubMed

    Tomaino, M; Mitsionis, G; Basitidas, J; Grewal, R; Pfaeffle, J

    1998-02-01

    The purpose of this study was to investigate the effect of partial excision of the A2 and A4 pulleys on digital angular rotation and the energy required to flex the finger. Partial excision of A2 resulted in a statistically significant decrease in angular rotation of 3 and 5% after 50 and 75% excision, respectively. Partial excision of A4 failed to produce any significant differences in angular rotation. Combined partial excision of A2 and A4 resulted in a significant decrease of 5 and 8% after 50 and 75% excision, respectively. Significant differences in work of flexion occurred only after excision of 75% of the A2 pulley. Although optimal finger function relies on the integrity of the A2 and A4 pulleys which maintain the efficiency of the digital flexor system, these data suggest that 25% of the A2 pulley, up to 75% of the A4 and 25% of the A2 and A4 together can be excised without significant effects on angular rotation.

  6. Are Pulley Exercises Initiated 6 Weeks After Rotator Cuff Repair a Safe and Effective Rehabilitative Treatment? A Randomized Controlled Trial.

    PubMed

    Baumgarten, Keith M; Osborn, Roy; Schweinle, Will E; Zens, Matthew J; Helsper, Elizabeth A

    2016-07-01

    There are few level 1 or 2 evidence studies that examine rehabilitation after rotator cuff repair. Pulleys have been used in postoperative shoulder rehabilitation with the intention of improving range of motion and developing strength. There is a concern that the use of pulleys in rehabilitation of rotator cuff repairs may contribute to excessive scapular motion (scapular substitution) and potentially inferior outcomes. Rotator cuff repair patients treated with pulley exercises would have increased scapular substitution and inferior patient-determined outcome scores, range of motion, and strength compared with patients treated with an alternative rehabilitation program without pulleys. Randomized controlled trial; Level of evidence, 1. A total of 27 patients who underwent rotator cuff repair were randomized to a rehabilitation group that used pulleys initiated 6 weeks postoperatively, and 26 patients followed a rehabilitation protocol without pulleys. Inclusion criteria were patients undergoing arthroscopic rotator cuff repair. Exclusion criteria were large to massive rotator cuff tears, revision rotator cuff repair, glenohumeral osteoarthritis, adhesive capsulitis, and a symptomatic contralateral shoulder. Outcomes of intervention were patient-determined outcome scores (Western Ontario Rotator Cuff Index [WORC], American Shoulder and Elbow Surgeons [ASES] Shoulder Score, Single Assessment Numeric Evaluation [SANE], Shoulder Activity Level, and Simple Shoulder Test [SST]), range of motion, scapular substitution, and strength. Outcomes were determined at 6, 12, 18, 26, and 52 weeks. A power analysis determined that 22 patients were needed per group to have a power of 0.80, α = 0.05, and effect size of f = 0.5. Both groups had statistically significant improvements in WORC, ASES Shoulder Score, SST, and SANE scores over time after rotator cuff repair (P < .0001). There were no differences between the interventions for WORC (P = .18), ASES Shoulder Score (P = .73

  7. The Roman Bridge: a "double pulley – suture bridges" technique for rotator cuff repair

    PubMed Central

    Franceschi, Francesco; Longo, Giuseppe Umile; Ruzzini, Laura; Rizzello, Giacomo; Maffulli, Nicola; Denaro, Vincenzo

    2007-01-01

    Background With advances in arthroscopic surgery, many techniques have been developed to increase the tendon-bone contact area, reconstituting a more anatomic configuration of the rotator cuff footprint and providing a better environment for tendon healing. Methods We present an arthroscopic rotator cuff repair technique which uses suture bridges to optimize rotator cuff tendon-footprint contact area and mean pressure. Results Two medial row 5.5-mm Bio-Corkscrew suture anchors (Arthrex, Naples, FL), which are double-loaded with No. 2 FiberWire sutures (Arthrex, Naples, FL), are placed in the medial aspect of the footprint. Two suture limbs from a single suture are both passed through a single point in the rotator cuff. This is performed for both anchors. The medial row sutures are tied using the double pulley technique. A suture limb is retrieved from each of the medial anchors through the lateral portal, and manually tied as a six-throw surgeon's knot over a metal rod. The two free suture limbs are pulled to transport the knot over the top of the tendon bridge. Then the two free suture limbs that were used to pull the knot down are tied. The end of the sutures are cut. The same double pulley technique is repeated for the other two suture limbs from the two medial anchors, but the two free suture limbs are used to produce suture bridges over the tendon, by means of a Pushlock (Arthrex, Naples, FL), placed 1 cm distal to the lateral edge of the footprint. Conclusion This technique maximizes the advantages of two techniques. On the one hand, the double pulley technique provides an extremely secure fixation in the medial aspect of the footprint. On the other hand, the suture bridges allow to improve pressurized contact area and mean footprint pressure. In this way, the bony footprint in not compromised by the distal-lateral fixation, and it is thus possible to share the load between fixation points. This maximizes the strength of the repair and provides a barrier

  8. The Roman Bridge: a "double pulley - suture bridges" technique for rotator cuff repair.

    PubMed

    Franceschi, Francesco; Longo, Umile Giuseppe; Ruzzini, Laura; Rizzello, Giacomo; Maffulli, Nicola; Denaro, Vincenzo

    2007-12-18

    With advances in arthroscopic surgery, many techniques have been developed to increase the tendon-bone contact area, reconstituting a more anatomic configuration of the rotator cuff footprint and providing a better environment for tendon healing. We present an arthroscopic rotator cuff repair technique which uses suture bridges to optimize rotator cuff tendon-footprint contact area and mean pressure. Two medial row 5.5-mm Bio-Corkscrew suture anchors (Arthrex, Naples, FL), which are double-loaded with No. 2 FiberWire sutures (Arthrex, Naples, FL), are placed in the medial aspect of the footprint. Two suture limbs from a single suture are both passed through a single point in the rotator cuff. This is performed for both anchors. The medial row sutures are tied using the double pulley technique. A suture limb is retrieved from each of the medial anchors through the lateral portal, and manually tied as a six-throw surgeon's knot over a metal rod. The two free suture limbs are pulled to transport the knot over the top of the tendon bridge. Then the two free suture limbs that were used to pull the knot down are tied. The end of the sutures are cut. The same double pulley technique is repeated for the other two suture limbs from the two medial anchors, but the two free suture limbs are used to produce suture bridges over the tendon, by means of a Pushlock (Arthrex, Naples, FL), placed 1 cm distal to the lateral edge of the footprint. This technique maximizes the advantages of two techniques. On the one hand, the double pulley technique provides an extremely secure fixation in the medial aspect of the footprint. On the other hand, the suture bridges allow to improve pressurized contact area and mean footprint pressure. In this way, the bony footprint in not compromised by the distal-lateral fixation, and it is thus possible to share the load between fixation points. This maximizes the strength of the repair and provides a barrier preventing penetration of synovial fluid

  9. Reliability of forced internal rotation and active internal rotation to assess lateral instability of the biceps pulley

    PubMed Central

    ARRIGONI, PAOLO; ROSE, GIACOMO DELLE; D’AMBROSI, RICCARDO; ROTUNDO, GIORGIO; CAMPAGNA, VINCENZO; PIRANI, PIERGIORGIO; PANASCÌ, MANLIO; PETRICCIOLI, DARIO; BERTONE, CELESTE; GRASSO, ANDREA; LATTE, CARMINE; COSTA, ALBERTO; VIOLA, GINO; DE GIORGI, SILVANA; PANELLA, ANTONELLO; PADUA, ROBERTO; BECCARINI, ALESSANDRO; SALCHER, BARBARA; OLIVIERI, MATTEO; MUGNAINI, MARCO; PANNONE, ANTONELLO; CEOLDO, CHIARA; LONGO, UMILE GIUSEPPE; DENARO, VINCENZO; CERCIELLO, SIMONE; PANNI, ALFREDO SCHIAVONE; AVANZI, PAOLO; ZORZI, CLAUDIO; RAGONE, VINCENZA; CASTAGNA, ALESSANDRO; RANDELLI, PIETRO

    2015-01-01

    Purpose the aim of this study was to investigate the relationship between positive painful forced internal rotation (FIR) and lateral pulley instability in the presence of a pre-diagnosed posterosuperior cuff tear. The same investigation was conducted for painful active internal rotation (AIR). Methods a multicenter prospective study was conducted in a series of patients scheduled to undergo arthroscopic posterosuperior cuff repair. Pain was assessed using a visual analog scale (VAS) and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) was administered. The VAS score at rest, DASH score, and presence/absence of pain on FIR and AIR were recorded and their relationships with lesions of the lateral pulley, cuff tear patterns and shape of lesions were analyzed. Results the study population consisted of 115 patients (mean age: 55.1 years) recruited from 12 centers. The dominant arm was affected in 72 cases (62.6%). The average anteroposterior extension of the lesion was 1.61 cm. The mean preoperative VAS and DASH scores were 6.1 and 41.8, respectively. FIR and AIR were positive in 94 (81.7%) and 85 (73.9%) cases, respectively. The lateral pulley was compromised in 50 cases (43.4%). Cuff tears were partial articular in 35 patients (30.4%), complete in 61 (53%), and partial bursal in 19 (16.5%). No statistical correlation between positive FIR or AIR and lateral pulley lesions was detected. Positive FIR and AIR were statistically associated with complete lesions. Negative FIR was associated with the presence of partial articular tears. Conclusions painful FIR in the presence of a postero-superior cuff tear does not indicate lateral pulley instability. When a cuff tear is suspected, positive FIR and AIR are suggestive of full-thickness tear patterns while a negative FIR suggests a partial articular lesion. Level of evidence: level I, validating cohort study with good reference standards. PMID:26151035

  10. Annexin A1 released from apoptotic cells acts through formyl peptide receptors to dampen inflammatory monocyte activation via JAK/STAT/SOCS signalling

    PubMed Central

    Pupjalis, Danute; Goetsch, Julia; Kottas, Diane J; Gerke, Volker; Rescher, Ursula

    2011-01-01

    The immunosuppressive effects of apoptotic cells involve inhibition of pro-inflammatory cytokine release and establishment of an anti-inflammatory cytokine profile, thus limiting the degree of inflammation and promoting resolution. We report here that this is in part mediated by the release of the anti-inflammatory mediator annexin A1 from apoptotic cells and the functional activation of annexin A1 receptors of the formyl peptide receptor (FPR) family on target cells. Supernatants from apoptotic neutrophils or the annexin A1 peptidomimetic Ac2-26 significantly reduced IL-6 signalling and the release of TNF-α from endotoxin-challenged monocytes. Ac2-26 activated STAT3 in a JAK-dependent manner, resulting in upregulated SOCS3 levels, and depletion of SOCS3 reversed the Ac2-26-mediated inhibition of IL-6 signalling. This identifies annexin A1 as part of the anti-inflammatory pattern of apoptotic cells and links the activation of FPRs to established signalling pathways triggering anti-inflammatory responses. PMID:21254404

  11. Activation of histamine H3-receptors inhibits carrier-mediated norepinephrine release during protracted myocardial ischemia. Comparison with adenosine A1-receptors and alpha2-adrenoceptors.

    PubMed

    Imamura, M; Lander, H M; Levi, R

    1996-03-01

    We previously showed that prejunctional histamine H3-receptors downregulate norepinephrine exocytosis, which is markedly enhanced in early myocardial ischemia. In the present study, we investigated whether H3-receptors modulate nonexocytotic norepinephrine release during protracted myocardial ischemia. In this setting, decreased pH(i) in sympathetic nerve endings sequentially leads to a compensatory activation of the Na+-H+ antiporter (NHE), accumulation of intracellular Na+, reversal of the neuronal uptake of norepinephrine, and thus carrier-mediated release of norepinephrine. Accordingly, norepinephrine overflow from isolated guinea pig hearts undergoing 20-minute global ischemia and 45-minute reperfusion was attenuated approximately 80% by desipramine (10 nmol/L) and 70% by 5-(N-ethyl-N-isopropyl)-amiloride (EIPA, 10 micromol/L), inhibitors of norepinephrine uptake and NHE, respectively. The H3-receptor agonist imetit (0.1 micromol/L) decreased carrier-mediated norepinephrine release by approximately 50%. This effect was blocked by the H3-receptor antagonist thioperamide (0.3 micromol/L), indicating that H-receptor activation inhibits carrier-mediated norepinephrine release. At lower concentrations, imetit (10 nmol/L) or EIPA (3 micromol/L) did not inhibit carrier-mediated norepinephrine release. However, a 25% inhibition occurred with imetit (10 nmol/L) and EIPA (3 micromol/L) combined. This synergism suggests an association between H-receptors and NHE. Conceivably, activation of H-receptors may lead to inhibition of NHE. In fact, alpha2-adrenoceptor activation, which is known to stimulate NHE, enhanced norepinephrine release, whereas alpha2-adrenoceptor blockade attenuated it. Furthermore, activation of adenosine A1-receptors markedly attenuated norepinephrine release, whereas their inhibition potentiated it. Because norepinephrine directly correlated with the severity of reperfusion arrhythmia and imetit reduced the incidence of ventricular fibrillation by 50

  12. Investigation of the Forces Acting on Gliders in Automobile-pulley-winch and Airplane Towed Flight

    NASA Technical Reports Server (NTRS)

    Klemperer, W B

    1942-01-01

    The magnitude, the direction, and the fluctuation of towing forces exerted upon gliders by towing them aloft behind an automobile, by means of a winch, and by airplane were measured under a variety of conditions covering a range from gentle to severe types of operation. For these tests the towing forces did not exceed 92 percent of the gross weight of the glider. The results indicate that in pulley and winch towing the towing forces are of about the same magnitude as in automobile towing. Speed increases in the accelerated phases of the towing jerks encountered in airplane towing can readily become critical as speeds in excess of placard speeds can be attained. Passage through the slipstream of the towing airplane can be equivalent to a severe gust that, at high speed, may impose high wing loads and require large control moments.

  13. Pulley reef: a deep photosynthetic coral reef on the West Florida Shelf, USA

    USGS Publications Warehouse

    Culter, J.K.; Ritchie, K.B.; Earle, S.A.; Guggenheim, D.E.; Halley, R.B.; Ciembronowicz, K.T.; Hine, A.C.; Jarrett, B.D.; Locker, S.D.; Jaap, W.C.

    2006-01-01

    Pulley Reef (24°50′N, 83°40′W) lies on a submerged late Pleistocene shoreline feature that formed during a sea-level stillstand from 13.8 to 14.5 ka (Jarrett et al. 2005). The reef is currently 60–75 m deep, exhibits 10–60% coral cover, and extends over approximately 160 km2 of the sea floor. Zooxanthellate corals are primarily Agaricia lamarcki, A. fragilis, Leptoseris cucullata, and less common Madracis formosa, M. pharensis, M. decactis, Montastraea cavernosa, Porites divaricata, Scolymia cubensis and Oculina tenella. Coralline algae are comparable in abundance to stony corals. Other macroalgae include Halimeda tuna, Dictyota divaricata, Lobophora variegata, Ventricatri ventricosa, Verdigelas pelas, and Kallymenia sp. Anadyomene menziesii is abundant. The reef provides a habitat for organisms typically observed at much shallower depths, and is the deepest known photosynthetic coral reef on the North America continental shelf (Fig. 1).

  14. Using a Smart-pulley Atwood machine to study rocket motion

    NASA Astrophysics Data System (ADS)

    Greenwood, M. Stautberg; Bernett, R.; Benavides, M.; Granger, S.; Plass, R.; Walters, S.

    1989-10-01

    The Atwood machine consisted of a funnel partly filled with water on one side and a fixed mass of 400 g on the other side. The ``rocket'' begins to ascend when the acceleration is momentarily zero. This occurs when the total mass of the rocket is slightly larger than 400 g due to the rocket's thrust. As the wheel of Pasco's Smart pulley rotates, signals are sent to the Apple computer and the software generates tables and graphs of position, speed, and acceleration as a function of time. Also presented is a numerical differentiation scheme that greatly reduces the scatter in the experimental data for the acceleration. The data are compared with theory, assuming that dm/dt is constant. The value of dm/dt necessary to fit the data is compared with that found by measuring the flow rate from the funnel directly. Excellent agreement is obtained for the two values of dm/dt.

  15. Design and simulation of a cable-pulley-based transmission for artificial ankle joints

    NASA Astrophysics Data System (ADS)

    Liu, Huaxin; Ceccarelli, Marco; Huang, Qiang

    2016-06-01

    In this paper, a mechanical transmission based on cable pulley is proposed for human-like actuation in the artificial ankle joints of human-scale. The anatomy articular characteristics of the human ankle is discussed for proper biomimetic inspiration in designing an accurate, efficient, and robust motion control of artificial ankle joint devices. The design procedure is presented through the inclusion of conceptual considerations and design details for an interactive solution of the transmission system. A mechanical design is elaborated for the ankle joint angular with pitch motion. A multi-body dynamic simulation model is elaborated accordingly and evaluated numerically in the ADAMS environment. Results of the numerical simulations are discussed to evaluate the dynamic performance of the proposed design solution and to investigate the feasibility of the proposed design in future applications for humanoid robots.

  16. Improvement by dynorphin A (1-13) of galanin-induced impairment of memory accompanied by blockade of reductions in acetylcholine release in rats.

    PubMed Central

    Hiramatsu, M.; Mori, H.; Murasawa, H.; Kameyama, T.

    1996-01-01

    1. Human galanin (0.32 nmol per rat, i.c.v.), an endogenous neuropeptide, administered 30 min before acquisition or retention trials, significantly impaired the acquisition of learning and recall of memory in a step-through type passive avoidance performance. 2. The role of dynorphin A (1-13) in learning and memory is controversial. Dynorphin A (1-13) (0.5 nmol per rat, i.c.v.) administered 5 min before galanin injection, completely antagonized these impairments. 3. Galanin significantly decreased acetylcholine release in the hippocampus 40 to 120 min after injection as determined by in vivo brain microdialysis. This peptide also decreased acetylcholine release, albeit to a lesser extent, from the frontal cortex. 4. Dynorphin A (1-13) (0.5 nmol per rat, i.c.v.) 5 min before galanin injection, completely blocked the decrease in extracellular acetylcholine concentration induced by galanin. 5. These antagonistic effects of dynorphin A (1-13) were abolished by treatment with norbinaltorphimine (5.44 nmol per rat, i.c.v.), a selective kappa-opioid receptor antagonist, 5 min before dynorphin A (1-13). 6. Dynorphin A (1-13) (0.5 nmol) itself had no effect on learning and memory and on the acetylcholine concentration in the hippocampus or the frontal cortex in normal rats. 7. These results suggest that the neuropeptide dynorphin A (1-13) ameliorates the galanin-induced impairment of learning and memory accompanied by abolition of reductions in acetylcholine release via kappa-opioid receptors. Images Figure 4 PMID:8735624

  17. Ca2+–Calmodulin regulates SNARE assembly and spontaneous neurotransmitter release via v-ATPase subunit V0a1

    PubMed Central

    Wang, Dong; Epstein, Daniel; Khalaf, Ossama; Srinivasan, Sankaranarayanan; Williamson, W. Ryan; Fayyazuddin, Amir; Quiocho, Florante A.

    2014-01-01

    Most chemical neurotransmission occurs through Ca2+-dependent evoked or spontaneous vesicle exocytosis. In both cases, Ca2+ sensing is thought to occur shortly before exocytosis. In this paper, we provide evidence that the Ca2+ dependence of spontaneous vesicle release may partly result from an earlier requirement of Ca2+ for the assembly of soluble N-ethylmaleimide–sensitive fusion attachment protein receptor (SNARE) complexes. We show that the neuronal vacuolar-type H+-adenosine triphosphatase V0 subunit a1 (V100) can regulate the formation of SNARE complexes in a Ca2+–Calmodulin (CaM)-dependent manner. Ca2+–CaM regulation of V100 is not required for vesicle acidification. Specific disruption of the Ca2+-dependent regulation of V100 by CaM led to a >90% loss of spontaneous release but only had a mild effect on evoked release at Drosophila melanogaster embryo neuromuscular junctions. Our data suggest that Ca2+–CaM regulation of V100 may control SNARE complex assembly for a subset of synaptic vesicles that sustain spontaneous release. PMID:24733584

  18. The ATP-binding cassette transporter A1 regulates phosphoantigen release and Vγ9Vδ2 T cell activation by dendritic cells

    PubMed Central

    Castella, Barbara; Kopecka, Joanna; Sciancalepore, Patrizia; Mandili, Giorgia; Foglietta, Myriam; Mitro, Nico; Caruso, Donatella; Novelli, Francesco; Riganti, Chiara; Massaia, Massimo

    2017-01-01

    Vγ9Vδ2 T cells are activated by phosphoantigens, such as isopentenyl pyrophosphate (IPP), which is generated in the mevalonate pathway of antigen-presenting cells. IPP is released in the extracellular microenvironment via unknown mechanisms. Here we show that the ATP-binding cassette transporter A1 (ABCA1) mediates extracellular IPP release from dendritic cells (DC) in cooperation with apolipoprotein A-I (apoA-I) and butyrophilin-3A1. IPP concentrations in the supernatants are sufficient to induce Vγ9Vδ2 T cell proliferation after DC mevalonate pathway inhibition with zoledronic acid (ZA). ZA treatment increases ABCA1 and apoA-I expression via IPP-dependent LXRα nuclear translocation and PI3K/Akt/mTOR pathway inhibition. These results close the mechanistic gap in our understanding of extracellular IPP release from DC and provide a framework to fine-tune Vγ9Vδ2 T cell activation via mevalonate and PI3K/Akt/mTOR pathway modulation. PMID:28580927

  19. Effects of combined open kinetic chain and closed kinetic chain training using pulley exercise machines on muscle strength and angiogenesis factors

    PubMed Central

    Jang, Ki Soeng; Kang, Sunghwun; Woo, Sang Heon; Bae, Ju Yong; Shin, Ki Ok

    2016-01-01

    [Purpose] This study investigated the effects of combined open kinetic chain and closed kinetic chain training using pulley exercise machines on muscle strength, anaerobic power, and blood levels of angiogenesis factors. [Subjects and Methods] Twenty male university students were equally divided between control and pulley training groups. The pulley-training group underwent 8 weeks of combined training. Open kinetic chain training consisted of 2 sets of 10 repetitions at 60% of one repetition maximum; closed kinetic chain training consisted of 2 sets of 10 repetitions of resistance exercise using the subject’s own body weight. Isokinetic strength (trunk and knee), anaerobic power, vascular endothelial growth factor, angiopoietin-1, angiopoietin-2, and follistatin were analyzed. [Results] After 8 weeks, flexor and extensor muscle strength significantly increased in the trunk and knee; average and peak power also increased significantly. Angiopoietin 1 increased 25% in the control group and 48% in the pulley training group; vascular endothelial growth factor and follistatin increased significantly in the pulley-training group after 8 weeks. [Conclusion] Eight weeks of combined training using pulley exercise machines effectively increased biochemical factors related to muscle growth, as well as muscle strength in the trunk and knees. PMID:27134393

  20. A Simplified Design with a Toothed Belt and Non-Circular Pulleys to Separate Parts from a Magazine File

    NASA Astrophysics Data System (ADS)

    Hanke, U.; Modler, K.-H.; Neumann, R.; Fischer, C.

    The objective of this paper is to simplify a very complex guidance mechanism, currently used for lid separating issues in a packaging-machine. The task of this machine is to pick up a lid from a magazine file, rotate it around 180° and place it on tins. The developed mechanism works successfully but with a very complex construction. It consists of a planetary cam mechanism, combined with a toothed gear (with a constant transmission ratio) and a guiding mechanism with a toothed belt and circular pulleys. Such complex constructions are very common in industrial solutions. The idea of the authors is to show a much simpler design in solving the same problem. They developed a guidance mechanism realizing the same function, consisting only of a toothed belt with non-circular pulleys. The used parts are common trade articles.

  1. Modeling the Impacts of the Loop Current on Circulation and Water Properties in Pulley Ridge Area, Southwest Florida Shelf

    NASA Astrophysics Data System (ADS)

    Pan, C.; Jiang, M.; Dalgleish, F.; Reed, J.

    2016-02-01

    A high resolution ( 1.5km) regional ocean model has been developed for the southern Florida Shelf and Florida Straits. Analysis of the model shows that the meandering of the Gulf of Mexico Loop Current exerts strong impacts on the circulation dynamics over the Pulley Ridge region on the southwestern Florida shelf, where the Loop Current (LC) turns east into Florida Straits to become Florida Current (FC). In particular, the northward migration of the LC/FC front tends to drive a strong onshelf (eastward) transport of the gulf water onto the southern Pulley Ridge, an important area where abundant photosynthetic corals can be found at depth between 60 and 90 m. Remotely or locally generated eddies over the western shelf slope of the Pulley Ridge can also be blocked by the northern LC/FC front when it is closely in contact with the shelf break. These eddies drive strong upwelling of slope water toward the shelf break and sometimes onto the shelf. In the southern Florida Straits, FC may also strongly interact with the shelf slope from the Dry Tortugas to the Florida Keys, often in association with the meandering of the Florida Current. Moreover, a significant return flow, largely within the upper 150 m, may be produced when the FC impinges upon the continental slope. The return flow may extend all the way from the contact point between the FC and shelf slope to the northwestern side of the Pulley Ridge, providing yet another mechanism for water exchange between the shelf and slope.

  2. Barbed versus smooth poly-propylene three-loop pulley sutures for repair of canine gastrocnemius tendon.

    PubMed

    Perry, B S; Harper, T A; Mitchell, M A; McFadden, M S; Heggem Perry, B

    2014-01-01

    To compare the ultimate tensile strength (UTS) and load to 1 and 3 mm gap formation of smooth (3-metric) and knotless barbed (4-metric) polypropylene sutures placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. In vitro. Thirty-three paired bone-tendon units with one of each pair assigned to each suture type. Barbed suture size was based on previously published materials testing results. Each unit was placed in a servo-hydraulic testing machine and tested under single cycle tensile loading until repair failure. There was a significantly higher UTS for smooth polypropylene compared to the barbed polypropylene repairs. The loads resulting in 1 and 3 mm gaps for the barbed repairs were consistently significantly less than the corresponding smooth polypropylene repair values. The knotted smooth polypropylene repair was consistently stronger than the knotless barbed polypropylene repair when placed in a three-loop pulley pattern for gastrocnemius repair. Knotless barbed polypropylene suture should not be considered equivalent to knotted smooth polypropylene of comparable tensile strength when placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. The low failure loads of the barbed repair are probably due to failure of the barbs to anchor consistently throughout the tendon in the knotless configuration.

  3. The Effects of Elbow Joint Angle Change on the Elbow Flexor Muscle Activation in Pulley with Weight Exercise

    PubMed Central

    Kang, Taewook; Seo, Youngjoon; Park, Jaehoon; Dong, Eunseok; Seo, Byungdo; Han, Dongwook

    2013-01-01

    [Purpose] This research investigated the effect of angular variation of flexion of the elbow joint on the muscle activation of elbow flexor muscles. [Subjects] The research subjects were 24 male college students with a dominant right hand who had no surgical or neurological disorders and gave their prior written consent to participation with full knowledge of the method and purpose of this study. [Methods] The subjects' shoulder joints stayed in the resting position, and the elbow joint was positioned at angles of 55°, 70°, and 90°. The angle between the pulley with weights and forearm stayed at 90°. Surface electromyography was used to measure muscle activities. Three measurements were made at each elbow angle, and every time the angle changed, two minutes rest was given. [Result] The muscle activities of the elbow flexors showed significant changes with change in the elbow joint angle, except for the biceps brachii activities between the angles of 55° and 70° of elbow flexion. The muscle activities of the biceps brachii and brachioradialis showed angle-related changes in the order of 55°, which showed the biggest value, followed by 70° and 90°. [Conclusion] In order to improve muscle strength of the elbow flexor using a pulley system, it seems more effective to have a 90° angle between the pulley with weights and the forearm when the muscle is stretched to a length 20% greater than its resting position. PMID:24259930

  4. The effects of elbow joint angle change on the elbow flexor muscle activation in pulley with weight exercise.

    PubMed

    Kang, Taewook; Seo, Youngjoon; Park, Jaehoon; Dong, Eunseok; Seo, Byungdo; Han, Dongwook

    2013-09-01

    [Purpose] This research investigated the effect of angular variation of flexion of the elbow joint on the muscle activation of elbow flexor muscles. [Subjects] The research subjects were 24 male college students with a dominant right hand who had no surgical or neurological disorders and gave their prior written consent to participation with full knowledge of the method and purpose of this study. [Methods] The subjects' shoulder joints stayed in the resting position, and the elbow joint was positioned at angles of 55°, 70°, and 90°. The angle between the pulley with weights and forearm stayed at 90°. Surface electromyography was used to measure muscle activities. Three measurements were made at each elbow angle, and every time the angle changed, two minutes rest was given. [Result] The muscle activities of the elbow flexors showed significant changes with change in the elbow joint angle, except for the biceps brachii activities between the angles of 55° and 70° of elbow flexion. The muscle activities of the biceps brachii and brachioradialis showed angle-related changes in the order of 55°, which showed the biggest value, followed by 70° and 90°. [Conclusion] In order to improve muscle strength of the elbow flexor using a pulley system, it seems more effective to have a 90° angle between the pulley with weights and the forearm when the muscle is stretched to a length 20% greater than its resting position.

  5. Inhibition of cholinergic neurotransmission by β3-adrenoceptors depends on adenosine release and A1-receptor activation in human and rat urinary bladders.

    PubMed

    Silva, Isabel; Costa, Ana Filipa; Moreira, Sílvia; Ferreirinha, Fátima; Magalhães-Cardoso, Maria Teresa; Calejo, Isabel; Silva-Ramos, Miguel; Correia-de-Sá, Paulo

    2017-08-01

    The direct detrusor relaxant effect of β3-adrenoceptor agonists as a primary mechanism to improve overactive bladder symptoms has been questioned. Among other targets, activation of β3-adrenoceptors downmodulate nerve-evoked acetylcholine (ACh) release, but there is insufficient evidence for the presence of these receptors on bladder cholinergic nerve terminals. Our hypothesis is that adenosine formed from the catabolism of cyclic AMP in the detrusor may act as a retrograde messenger via prejunctional A1 receptors to explain inhibition of cholinergic activity by β3-adrenoceptors. Isoprenaline (1 µM) decreased [(3)H]ACh release from stimulated (10 Hz, 200 pulses) human (-47 ± 5%) and rat (-38 ± 1%) detrusor strips. Mirabegron (0.1 µM, -53 ± 8%) and CL316,243 (1 µM, -37 ± 7%) mimicked isoprenaline (1 µM) inhibition, and their effects were prevented by blocking β3-adrenoceptors with L748,337 (30 nM) and SR59230A (100 nM), respectively, in human and rat detrusor. Mirabegron and isoprenaline increased extracellular adenosine in the detrusor. Blockage of A1 receptors with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 100 nM) or the equilibrative nucleoside transporters (ENT) with dipyridamole (0.5 µM) prevented mirabegron and isoprenaline inhibitory effects. Dipyridamole prevented isoprenaline-induced adenosine outflow from the rat detrusor, and this effect was mimicked by the ENT1 inhibitor, S-(4-nitrobenzyl)-6-thioinosine (NBTI, 30 µM). Cystometry recordings in anesthetized rats demonstrated that SR59230A, DPCPX, dipyridamole, and NBTI reversed the decrease in the voiding frequency caused by isoprenaline (0.1-1,000 nM). Data suggest that inhibition of cholinergic neurotransmission by β3-adrenoceptors results from adenosine release via equilibrative nucleoside transporters and prejunctional A1-receptor stimulation in human and rat urinary bladder. Copyright © 2017 the American Physiological Society.

  6. Modulation of sarcoplasmic reticulum Ca2+ release in skeletal muscle expressing ryanodine receptor impaired in regulation by calmodulin and S100A1.

    PubMed

    Yamaguchi, Naohiro; Prosser, Benjamin L; Ghassemi, Farshid; Xu, Le; Pasek, Daniel A; Eu, Jerry P; Hernández-Ochoa, Erick O; Cannon, Brian R; Wilder, Paul T; Lovering, Richard M; Weber, David; Melzer, Werner; Schneider, Martin F; Meissner, Gerhard

    2011-05-01

    In vitro, calmodulin (CaM) and S100A1 activate the skeletal muscle ryanodine receptor ion channel (RyR1) at submicromolar Ca(2+) concentrations, whereas at micromolar Ca(2+) concentrations, CaM inhibits RyR1. One amino acid substitution (RyR1-L3625D) has previously been demonstrated to impair CaM binding and regulation of RyR1. Here we show that the RyR1-L3625D substitution also abolishes S100A1 binding. To determine the physiological relevance of these findings, mutant mice were generated with the RyR1-L3625D substitution in exon 74, which encodes the CaM and S100A1 binding domain of RyR1. Homozygous mutant mice (Ryr1(D/D)) were viable and appeared normal. However, single RyR1 channel recordings from Ryr1(D/D) mice exhibited impaired activation by CaM and S100A1 and impaired CaCaM inhibition. Isolated flexor digitorum brevis muscle fibers from Ryr1(D/D) mice had depressed Ca(2+) transients when stimulated by a single action potential. However, during repetitive stimulation, the mutant fibers demonstrated greater relative summation of the Ca(2+) transients. Consistently, in vivo stimulation of tibialis anterior muscles in Ryr1(D/D) mice demonstrated reduced twitch force in response to a single action potential, but greater summation of force during high-frequency stimulation. During repetitive stimulation, Ryr1(D/D) fibers exhibited slowed inactivation of sarcoplasmic reticulum Ca(2+) release flux, consistent with increased summation of the Ca(2+) transient and contractile force. Peak Ca(2+) release flux was suppressed at all voltages in voltage-clamped Ryr1(D/D) fibers. The results suggest that the RyR1-L3625D mutation removes both an early activating effect of S100A1 and CaM and delayed suppressing effect of CaCaM on RyR1 Ca(2+) release, providing new insights into CaM and S100A1 regulation of skeletal muscle excitation-contraction coupling.

  7. Facilitating endoscopic submucosal dissection: the suture-pulley method significantly improves procedure time and minimizes technical difficulty compared with conventional technique: an ex vivo study (with video)

    PubMed Central

    Aihara, Hiroyuki; Kumar, Nitin; Ryou, Marvin; Abidi, Wasif; Ryan, Michele B.; Thompson, Christopher C.

    2015-01-01

    Background The lack of countertraction in endoscopic submucosal dissection (ESD) results in increased technical demand and procedure time. Although the suture-pulley method for countertraction has been reported, its effectiveness compared with the traditional ESD technique remains unclear. Objective To objectively analyze efficacy of countertraction using the suture-pulley method for ESD. Design Prospective ex vivo animal study. Setting Animal laboratory. Interventions Twenty simulated gastric lesions were created in porcine stomachs by using a standard circular template 30 mm in diameter. In the control arm (n = 10), ESD was performed by using the standard technique. In the suture-pulley arm (N = 10), a circumferential incision was made, and an endoscopic suturing device was used to place the suture pulley. Main Outcome Measurements The primary outcome of this study was total procedure time. Results The median total procedure time with the suture-pulley method was significantly shorter than the traditional ESD technique (median, 25% to 75%, interquartile range [IQR]: 531 seconds [474.3–549.3 seconds] vs 845 seconds [656.3–1547.5 seconds], P < .001). The median time (IQR) for suture-pulley placement was 160.5 seconds (150.0–168.8 seconds). Although there was a significantly longer procedure time for proximal versus middle/lower stomach lesions with traditional ESD (median, 1601 seconds; IQR, 1547.5–1708.8 seconds vs median, 663 seconds; IQR, 627.5–681.8 seconds; P =.01), there was no significant difference in procedure time for lesions of various locations when using the suture-pulley method. Compared with traditional ESD, the suture-pulley method was less demanding in all categories evaluated by the NASA Task Load Index. Limitations Ex vivo study. Conclusions The suture-pulley method facilitates direct visualization of the submucosal layer during ESD and significantly reduces procedure time and technical difficulty. In addition, the benefit of the suture-pulley

  8. Protein kinase C activation increases noradrenaline release from the rat hippocampus and modifies the inhibitory effect of alpha 2-adrenoceptor and adenosine A1-receptor agonists.

    PubMed

    Fredholm, B B; Lindgren, E

    1988-05-01

    We have studied the effect of stimulating protein kinase C with phorbol esters on the release of [3H]-noradrenaline (NA) in the absence or presence of presynaptic alpha 2-adrenoceptor blocking agents and compared that to the elevation of cyclic AMP levels more than 10-fold by a combination of rolipram and forskolin. 4-beta-Phorbol 12,13-dibutyrate (PDiBu) increased stimulated (3 Hz) [3H]-NA release markedly and in a concentration dependent manner. 4-alpha-Phorbol-12,13-didecanoate was ineffective. The effect of PDiBu was not significantly reduced by nifedipine (1 microM), but was proportionally less in the presence of an alpha 2-adrenoceptor antagonist, yohimbine. PDiBu inhibited the presynaptic effect of alpha 2-adrenoceptor agonists clonidine and UK 14304. By contrast, the presynaptic effect of the adenosine analogue R-PIA was not reduced by PDiBu. PDiBu caused an increase in cyclic AMP that depended on adenosine receptor stimulation. Elevation of cyclic AMP had a limited effect on NA release from rat hippocampus, and did not significantly decrease the presynaptic inhibitory effect of UK 14304 (0.1 microM), of morphine (1 microM) or of the adenosine A1-receptor agonist CHA (1 microM). The effect of phorbol esters and several presynaptic inhibitors of NA-release in the rat hippocampus cannot be explained by changes in cyclic AMP levels in the tissue. Phorbol esters that stimulate protein kinase C appear to interact with a target that is the site of action alpha 2-adrenoceptors in this tissue. This site is not a dihydropyridine sensitive Ca-channel and is also different from the target of presynaptic adenosine receptors. Thus, activation of protein kinase C discriminates between apparently similar presynaptic mechanisms.

  9. Treatment of unfavourable results of flexor tendon surgery: Ruptured repairs, tethered repairs and pulley incompetence

    PubMed Central

    Elliot, David; Giesen, Thomas

    2013-01-01

    As primary repair of divided flexor tendons becomes more common, secondary tendon surgery becomes largely that of the complications of primary repair, namely ruptured and adherent repairs. These occur with an incidence of each in most reported series world-wide of around 5%, with these problems having changed little in the last two decades, despite strengthening our suture repairs. Where the primary referral service is less well-developed, and as a more occasional occurrence where primary treatment is the routine, the surgeon faces different problems. Patients arrive at a hand unit variable, but longer, times after the primary insult, having had no, or bad, previous treatment. Sometimes the situation is the same, viz. an extended finger with no active flexion, but now no longer amenable to primary repair. Frequently, it is much more complex as a result of injuries to the other tissues of the digit and, also, as a result of the unaided healing process within the digit in the presence of an inactive flexor system. We present our experience in dealing with ruptured repairs, tethered repairs and pulley incompetence. PMID:24459333

  10. Recovery of rock climbing performance after surgical reconstruction of finger pulleys.

    PubMed

    Bouyer, M; Forli, A; Semere, A; Chedal Bornu, B J; Corcella, D; Moutet, F

    2016-05-01

    This study evaluated recovery of sport performance and correction of bowstringing after surgical reconstruction of closed finger pulley rupture in high-level rock climbers. A total of 38 patients treated with an extensor retinaculum graft were assessed. The mean follow-up time was 85 months, and 30 patients returned to their previous climbing level. The mean total active motion score was 96% of the opposite side. All patients had an excellent Buck-Gramcko score. There was no significant difference in grip strength and tip pinch strength in the crimp position between the injured side and the opposite side. A total of 31 patients were examined with ultrasonography. In 18, flexor bowstringing effects had returned to near-normal values. There was an association between rock climbing level recovery and the flexor bowstringing correction (odds ratio, 6.9; 95% confidence interval, 1.1-42.8). If flexor bowstringing was corrected, patients were more likely to regain their preinjury sport performance. The ultrasonography measurement was a useful tool for predicting functional recovery. 4. © The Author(s) 2016.

  11. The 5-HT1A/1B-receptor agonist eltoprazine increases both catecholamine release in the prefrontal cortex and dopamine release in the nucleus accumbens and decreases motivation for reward and "waiting" impulsivity, but increases "stopping" impulsivity.

    PubMed

    Korte, S Mechiel; Prins, Jolanda; Van den Bergh, Filip S; Oosting, Ronald S; Dupree, Rudy; Korte-Bouws, Gerdien A H; Westphal, Koen G C; Olivier, Berend; Denys, Damiaan A; Garland, Alexis; Güntürkün, Onur

    2017-01-05

    The 5-HT1A/1B-receptor agonist eltoprazine has a behavioral drug signature that resembles that of a variety of psychostimulant drugs, despite the differences in receptor binding profile. These psychostimulants are effective in treating impulsivity disorders, most likely because they increase norepinephrine (NE) and dopamine (DA) levels in the prefrontal cortex. Both amphetamine and methylphenidate, however, also increase dopamine levels in the nucleus accumbens (NAc), which has a significant role in motivation, pleasure, and reward. How eltoprazine affects monoamine release in the medial prefrontal cortex (mPFC), the orbitofrontal cortex (OFC), and the NAc is unknown. It is also unknown whether eltoprazine affects different forms of impulsivity and brain reward mechanisms. Therefore, in the present study, we investigate the effects of eltoprazine in rats in the following sequence: 1) the activity of the monoaminergic systems using in vivo microdialysis, 2) motivation for reward measured using the intracranial self-stimulation (ICSS) procedure, and finally, 3) "waiting" impulsivity in the delay-aversion task, and the "stopping" impulsivity in the stop-signal task. The microdialysis studies clearly showed that eltoprazine increased DA and NE release in both the mPFC and OFC, but only increased DA concentration in the NAc. In contrast, eltoprazine decreased 5-HT release in the mPFC and NAc (undetectable in the OFC). Remarkably, eltoprazine decreased impulsive choice, but increased impulsive action. Furthermore, brain stimulation was less rewarding following eltoprazine treatment. These results further support the long-standing hypothesis that "waiting" and "stopping" impulsivity are regulated by distinct neural circuits, because 5-HT1A/1B-receptor activation decreases impulsive choice, but increases impulsive action. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Lesions of the biceps pulley: diagnostic accuracy of MR arthrography of the shoulder and evaluation of previously described and new diagnostic signs.

    PubMed

    Schaeffeler, Christoph; Waldt, Simone; Holzapfel, Konstantin; Kirchhoff, Chlodwig; Jungmann, Pia M; Wolf, Petra; Stat, Dipl; Schröder, Michael; Rummeny, Ernst J; Imhoff, Andreas B; Woertler, Klaus

    2012-08-01

    To retrospectively determine the diagnostic accuracy of magnetic resonance (MR) arthrography of the shoulder in the evaluation of lesions of the biceps pulley and to evaluate previously described and new diagnostic signs. Institutional review board approval was obtained; the requirement for informed consent was waived. MR arthrograms of 80 consecutive patients (mean age, 34.2 years; 53 male, 27 female) with arthroscopically proved intact or torn pulley systems were assessed for the presence of a pulley lesion by three radiologists who were blinded to arthroscopic results. Criteria evaluated were displacement of the long head of the biceps tendon (LHBT) relative to the subscapularis tendon on oblique sagittal images (displacement sign), medial subluxation of the LHBT on transverse images, nonvisibility or discontinuity of the superior glenohumeral ligament (SGHL), presence of biceps tendinopathy, and rotator cuff tears adjacent to the rotator interval. There were 28 pulley lesions noted at arthroscopy. For observers 1, 2, and 3, respectively: MR arthrography showed a sensitivity of 89%, 86%, and 82% and a specificity of 96%, 98%, and 87% in the detection of pulley lesions. Nonvisibility or discontinuity of the SGHL was sensitive (79%, 89%, and 79%) and specific (83%, 79%, and 75%). With the displacement sign, sensitivity was 86%, 82%, and 75% and specificity was 96%, 98%, 90%. Tendinopathy of the LHBT on oblique sagittal images showed a sensitivity of 93%, 82%, 64%; specificity was 81%, 96%, and 85%. Subluxation of the LHBT was insensitive (36%, 50%, and 64%) but specific (100%, 98%, and 96%). MR arthrography is accurate in the detection of pulley lesions; the displacement sign, nonvisibility or discontinuity of the SGHL, and tendinopathy of the LHBT on oblique sagittal images are the most accurate criteria for the detection of pulley lesions.

  13. Long-Term Outcome of Medial Rectus Recession and Pulley Posterior Fixation in Esotropia With High AC/A Ratio

    PubMed Central

    Wabulembo, Geoffrey; Demer, Joseph L.

    2014-01-01

    Purpose: Medial rectus (MR) recession with pulley posterior fixation (PF) can be used to treatesotropia (ET) with a high accommodative convergence to accommodation (AC/A) ratio as effectively in the short term as MR recession with scleral PF. This study provides a novel examination of the long-term results of MR recession with pulley PF (PPF). Methods: In 21 children we performed bilateral MR recession and pulley PF for ET greater at near than distance (high AC/A). Mean follow-up was 3.5 ± 2.5 (standard deviation [SD]) years. Results: Mean age at presentation was 2.7 ± 1.8 and at surgery 4.3 ± 1.6 years. Fourteen (67%) children had amblyopia. Distance and near pre-operative ET averaged 19.6Δ ± 10.5Δ and 36.9Δ ± 18.9Δ, respectively. Mean near-distance (N-D) disparity was 16.4Δ ± 12.3Δ. The MR recession averaged 4.4 ± 0.9 mm. Early mean postoperative ET was 1.3 ± 3.3Δ at distance and 2.8Δ ± 5.2Δ at near. Mean late postoperative ET was 0.1Δ ± 5.8Δ and 1.0Δ ± 6.2Δ at distance and near, respectively. At the final postoperative examination, mean N-D disparity was reduced to 0.9Δ ± 3.6Δ. Discussion: MR recession with PPF has a high long-term effectiveness, even in patients with amblyopia and autism. Since no posterior scleral suturing is required, it minimizes the perforation risk associated with scleral PF. Conclusion: MR recession with PPF is a safe and highly effective long-term treatment for ET with high AC/A ratio. Long-term results may surpass those of alternate procedures. PMID:22906381

  14. Arthroscopic double-pulley remplissage technique for engaging Hill-Sachs lesions in anterior shoulder instability repairs.

    PubMed

    Koo, Samuel S; Burkhart, Stephen S; Ochoa, Eloy

    2009-11-01

    We present a modified arthroscopic technique used to treat anterior shoulder instability associated with mild glenoid bone loss and a large Hill-Sachs lesion. The procedure aims to convert a bony intra-articular defect into an extra-articular defect by insetting the infraspinatus into the Hill-Sachs lesion. The arthroscopic procedure is performed with the patient in the lateral decubitus position, and the same portals used for anterior instability repair are used for this technique. The sequence of steps involves placing and passing the glenoid anchors and sutures and then waiting to tie the anterior sutures until after the humeral suture anchors have been placed. The subacromial bursa is cleared; then 2 transtendon suture anchors are placed in the Hill-Sachs lesion. Next, the previously placed Bankart repair sutures are tied, and finally, the remplissage sutures are tied in the subacromial space over the infraspinatus by use of the transtendon double-pulley technique. This technique uses the eyelets of the 2 suture anchors as pulleys and creates a double-mattress suture.

  15. GIS compilation of data collected from the Pulley Ridge Deep Coral Reef region

    USGS Publications Warehouse

    Cross, VeeAnn; Twichell, D.C.; Halley, R.B.; Ciembronowicz, K.T.; Jarrett, B.D.; Hammar-Klose, E.S.; Hine, A.C.; Locker, S.D.; Naar, D.F.

    2005-01-01

    Pulley Ridge is a chain of drowned barrier islands that extends almost 200 km in 60-90 m water depths (Fig. 1). This drowned ridge is located on the Florida Platform in the southeastern Gulf of Mexico about 250 km west of Cape Sable, Florida (Jarrett and others, 2005). These islands formed during the early Holocene marine transgression approximately 12,000 - 14,000 years before present, and were then submerged by sea level rise and preserved near the outer edge of the Florida Platform. The southern portion of Pulley Ridge is the focus of this study. This area hosts zooxanthellate scleractinian corals, green, red and brown macro algae, and a mix of deep and typically shallow-water tropical fishes. This largely photosynthetic community is unique in that it thrives with less than 5% of the light typically associated with shallow-water reefs with similar fauna.Several factors help to account for the existence of this unique deep-water community. First, the underlying drowned barrier islands provide both elevated topography and lithified substrate for the establishment of the hardbottom community. Second, the region is commonly bathed by the Loop Current, which brings relatively clear and warm water to this area. Third, the ridge's position on the continental shelf places it within the thermocline which provides nutrients to the reef during upwelling (Halley and others, 2003).The USGS has made two proposals to resource managers for the designation of marine protected areas based on the geophysical and photographic data in this report. The proposals describe areas that may require some regulatory protection of marine life utilizing the sea floor (Fig. 1).The first proposal is that the area of greatest hermatypic coral cover (Fig. 1) is considered for future management actions and designated a Habitat Area of Particular Concern (HAPC) by the Gulf of Mexico Fishery Management Council. HAPCs are identified on the basis of habitat level considerations:The importance of the

  16. Long-term outcome of medial rectus recession and pulley posterior fixation in esotropia with high AC/A ratio.

    PubMed

    Wabulembo, Geoffrey; Demer, Joseph L

    2012-09-01

    Medial rectus (MR) recession with pulley posterior fixation (PF) can be used to treatesotropia (ET) with a high accommodative convergence to accommodation (AC/A) ratio as effectively in the short term as MR recession with scleral PF. This study provides a novel examination of the long-term results of MR recession with pulley PF (PPF). In 21 children we performed bilateral MR recession and pulley PF for ET greater at near than distance (high AC/A). Mean follow-up was 3.5 ± 2.5 (standard deviation [SD]) years. Mean age at presentation was 2.7 ± 1.8 and at surgery 4.3 ± 1.6 years. Fourteen (67%) children had amblyopia. Distance and near pre-operative ET averaged 19.6Δ ± 10.5Δ and 36.9Δ ±18.9Δ, respectively. Mean near-distance (N-D) disparity was 16.4Δ ± 12.3Δ. The MR recession averaged 4.4 ± 0.9 mm. Early mean postoperative ET was 1.3 ± 3.3Δ at distance and 2.8Δ ± 5.2Δ at near. Mean late postoperative ET was 0.1Δ ± 5.8Δ and 1.0Δ ± 6.2Δ at distance and near, respectively. At the final postoperative examination, mean N-D disparity was reduced to 0.9Δ ± 3.6Δ. MR recession with PPF has a high long-term effectiveness, even in patients with amblyopia and autism. Since no posterior scleral suturing is required, it minimizes the perforation risk associated with scleral PF. MR recession with PPF is a safe and highly effective long-term treatment for ET with high AC/A ratio. Long-term results may surpass those of alternate procedures.

  17. Modeling the impacts of the Loop Current on circulation and water properties over the Pulley Ridge region on the Southwest Florida shelf

    NASA Astrophysics Data System (ADS)

    Pan, Chudong; Jiang, Mingshun; Dalgleish, Fraser R.; Reed, John K.

    2017-04-01

    A high-resolution (∼1.5 km) regional ocean model was developed for the southern Florida Shelf and Florida Straits. A two-year (2011-12) simulation was conducted and the model results were generally in good agreement with available satellite and in situ data. Model results show that the meandering of the Gulf of Mexico Loop Current (LC) exerts strong impacts on the dynamics over Pulley Ridge on the southwest Florida shelf, where the LC turns into the Florida Straits to become the Florida Current (FC). In particular, the northward migration of the LC/FC front often drives strong on-shelf (eastward) transport of the slope water onto the shelf of southern Pulley Ridge, an important mesophotic coral reef at depths between 60 and 90 m. Frequent remotely or locally generated eddies over the western slope of Pulley Ridge may be blocked by the northern LC/FC front when it is closely in contact with the shelf break, a phenomenon documented in previous studies. These eddies drive strong upwelling of slope water toward the shelf break, which sometimes can extend 20-30 km onto the shelf, strongly affecting the Pulley Ridge region. A narrow return flow, largely along the shelf edge from Florida Keys to Pulley Ridge, may be produced when the FC impinges upon the continental slope during late fall to early spring. The results from an experiment without the surface winds suggest that wind forcing contributes to the westward flow but is not the determining factor for its generation.

  18. Subject competency of teachers and level of dependence on resource packs to teach levers, gears and pulleys

    NASA Astrophysics Data System (ADS)

    Jarvis, Tina; Cavendish, Sue

    1994-12-01

    This pilot study set out to ascertain whether the level of dependence on resource material is related to teaching experience, existing understanding in mechanics, and perceived self confidence in science and technology. Details of teaching experience and qualifications were obtained from 11 experienced teachers and 10 initial teacher trainees, and understanding of mechanics was assessed by a written test. Each teacher worked through one commercially produced inservice pack about levers, pulleys or gears, and then prepared a 30 minute session for 4 ten year old children. Videos of the sessions were analysed with respect to the extent to which the pack was the sole focus; the amount of integration with other teaching aids and approaches; and the extent individual children's needs were satisfied. Although science qualifications influenced teacher confidence, they were not accurate predictors of relevant knowledge and teaching competence. As the majority of teachers followed pack instructions closely, the children's needs were not always well matched.

  19. Arthroscopic Transtendinous Double-Pulley Remplissage Technique in the Beach-Chair Position for Large Hill-Sachs Lesions

    PubMed Central

    Parnes, Nata; Carey, Paul A.; Schumacher, Christopher; Price, Mark D.

    2015-01-01

    Hill-Sachs lesions are a common finding in patients with glenohumeral instability. There have been numerous methods described for addressing Hill-Sachs deformity. One popular method includes transferring a portion of the infraspinatus muscle into the posterior-superior defect (remplissage) to prevent the lesion from engaging and the resultant instability. We present a method of arthroscopic remplissage whereby the lesion is addressed through transtendinous insertion of arthroscopic anchors. Once 2 anchors have been inserted, 1 limb of each suture is tied to the other anchor, the so-called pulley repair technique. This can be performed either under direct visualization in the subacromial space or blindly while the surgeon is viewing from the articular side. Once both limbs have been tied, the infraspinatus tendon nicely spans the defect, and there has been minimal morbidity to the tendon itself. We have found this method to be useful for addressing a large Hill-Sachs deformity. PMID:26759767

  20. Cerclage wire-plate composite for fixation of quadrilateral plate fractures of the acetabulum: a checkrein and pulley technique.

    PubMed

    Farid, Yasser R

    2010-05-01

    Acetabular fractures with complete or incomplete quadrilateral plate separation frequently present with central displacement of the femoral head. Failure of stable fixation of medial wall fractures leaves residual subluxation despite reduction of other fracture components. Several fixation techniques may be either technically demanding or insufficient for stable fixation in conditions of comminution, osteoporosis, or neglected injuries. The proposed wire-plate composite uses a reconstruction spring plate over the pelvic brim for medial wall buttressing. One hole on its true pelvic limb provides a pulley to deviate a cerclage wire or cable passed through the greater sciatic notch into the true pelvis. This enhances buttressing against medial protrusion. Application through anterior approaches is simple and fixation is reliable in difficult fractures without the risk of joint penetration because all quadrilateral plate buttressing implants remain extraosseous.

  1. Modeling the frictional interaction in the tendon-pulley system of the human finger for use in robotics.

    PubMed

    Dermitzakis, Konstantinos; Morales, Marco Roberto; Schweizer, Andreas

    2013-01-01

    Physiological studies of the human finger indicate that friction in the tendon-pulley system accounts for a considerable fraction of the total output force (9-12%) in a high-load static posteccentric configuration. Such a phenomenon can be exploited for robotic and prosthetic applications, as it can result in (1) an increase of output force or (2) a reduction of energy consumption and actuator weight. In this study, a simple frictional, two-link, one-degree-of-freedom model of a human finger was created. The model is validated against in vitro human finger data, and its behavior is examined with respect to select physiological parameters. The results point to clear benefits of incorporating friction in tendon-driven robotic fingers for actuator mass and output force. If it is indeed the case that the majority of high-load hand grasps are posteccentric, there is a clear benefit of incorporating friction in tendon-driven prosthetic hand replacements.

  2. The human sodium-dependent ascorbic acid transporters SLC23A1 and SLC23A2 do not mediate ascorbic acid release in the proximal renal epithelial cell

    PubMed Central

    Eck, Peter; Kwon, Oran; Chen, Shenglin; Mian, Omar; Levine, Mark

    2013-01-01

    Sodium-dependent ascorbic acid membrane transporters SLC23A1 and SLC23A2 mediate ascorbic acid (vitamin C) transport into cells. However, it is unknown how ascorbic acid undergoes cellular release, or efflux. We hypothesized that SLC23A1 and SLC23A2 could serve a dual role, mediating ascorbic acid cellular efflux as well as uptake. Renal reabsorption is required for maintaining systemic vitamin C concentrations. Because efflux from nephron cells is necessary for reabsorption, we studied whether SLC23A1 and SLC23A2 mediate efflux of ascorbic acid in the human renal nephron. We found high gene expression of SLC23A1 but no expression of SLC23A2 in the proximal convoluted and straight tubules of humans. These data rule out SLC23A2 as the ascorbic acid release protein in the renal proximal tubular epithelia cell. We utilized a novel dual transporter-based Xenopus laevis oocyte system to investigate the function of the SLC23A1 protein, and found that no ascorbate release was mediated by SLC23A1. These findings were confirmed in mammalian cells overexpressing SLC23A1. Taken together, the data for SLC23A1 show that it too does not have a role in cellular release of ascorbic acid across the basolateral membrane of the proximal tubular epithelial cell, and that SLC23A1 alone is responsible for ascorbic acid uptake across the apical membrane. These findings reiterate the physiological importance of proper functioning of SLC23A1 in maintaining vitamin C levels for health and disease prevention. The ascorbate efflux mechanism in the proximal tubule of the kidney remains to be characterized. PMID:24400138

  3. Is there a difference in the pattern of muscle activity when performing neck exercises with a guild board versus a pulley?

    PubMed

    Peolsson, Anneli; Peolsson, Michael; Jull, Gwendolen; O' Leary, Shaun

    2013-09-01

    Guild boards and pulleys are apparatus commonly used to train cervical muscle function for their purported benefit in facilitating activity of the deeper muscle layers, although this effect has not been substantiated. The objective of this study was to compare the activity of the different layers of cervical muscles when performing exercise with these 2 types of apparatus. A total of 19 healthy persons (mean age 28 years, (standard deviation 7 years). Ultrasound measurements of muscle deformation and deformation rate were recorded from the dorsal and ventral neck muscle layers during extension and flexion exercises. Pulley exercises were performed in the upright sitting position against a standardized resistance (men 2 kg, women 1 kg) and guild board exercises at an angle of 45º. The dorsal muscles generally showed greater levels of deformation and deformation rate during exercise with the guild board compared with the pulley system (p < 0.05), but with no significant differences in relative activity between the deep and superficial muscle layers (condition × muscle interaction (p > 0.05)). No differences were observed for the ventral muscles between exercise methods (p > 0.05). While both exercise methods appear to train cervical muscle function, neither appear to be more selective in facilitating deep cervical muscle activity, probably as they involve very similar cervical kinematics.

  4. Facilitating endoscopic submucosal dissection: the suture-pulley method significantly improves procedure time and minimizes technical difficulty compared with conventional technique: an ex vivo study (with video).

    PubMed

    Aihara, Hiroyuki; Kumar, Nitin; Ryou, Marvin; Abidi, Wasif; Ryan, Michele B; Thompson, Christopher C

    2014-09-01

    The lack of countertraction in endoscopic submucosal dissection (ESD) results in increased technical demand and procedure time. Although the suture-pulley method for countertraction has been reported, its effectiveness compared with the traditional ESD technique remains unclear. To objectively analyze efficacy of countertraction using the suture-pulley method for ESD. Prospective ex vivo animal study. Animal laboratory. Twenty simulated gastric lesions were created in porcine stomachs by using a standard circular template 30 mm in diameter. In the control arm (n = 10), ESD was performed by using the standard technique. In the suture-pulley arm (N = 10), a circumferential incision was made, and an endoscopic suturing device was used to place the suture pulley. The primary outcome of this study was total procedure time. The median total procedure time with the suture-pulley method was significantly shorter than the traditional ESD technique (median, 25% to 75%, interquartile range [IQR]: 531 seconds [474.3-549.3 seconds] vs 845 seconds [656.3-1547.5 seconds], P < .001). The median time (IQR) for suture-pulley placement was 160.5 seconds (150.0-168.8 seconds). Although there was a significantly longer procedure time for proximal versus middle/lower stomach lesions with traditional ESD (median, 1601 seconds; IQR, 1547.5-1708.8 seconds vs median, 663 seconds; IQR, 627.5-681.8 seconds; P = .01), there was no significant difference in procedure time for lesions of various locations when using the suture-pulley method. Compared with traditional ESD, the suture-pulley method was less demanding in all categories evaluated by the NASA Task Load Index. Ex vivo study. The suture-pulley method facilitates direct visualization of the submucosal layer during ESD and significantly reduces procedure time and technical difficulty. In addition, the benefit of the suture-pulley method was seen for both simple and more complicated ESDs. Copyright © 2014. Published by Mosby, Inc.

  5. Electromyographyc evaluation of movements of lower limb in double pulley system equipment: comparison between gastrocnemius (caput laterale) and gluteus maximus.

    PubMed

    Tassi, N; Engrácia Valenti, V

    2007-09-01

    It was evaluated movements of lower limb in the double pulley system equipment on ten male volunteers during contraction of gastrocnemius (caput laterale) and gluteus maximus muscles in the following movements: 1) hip extension with extended knee and erect trunk, 2) hip extension with flexed knee and erect trunk, 3) hip extension with flexed knee and erect trunk, 3) hip extension with extended knee and inclined trunk, 5) hip abduction along the midline, 7) hip abduction with extension beyond the midline, 8) adduction with hip flexion beyond the midline, 8) adduction with hip flexion beyond the midline, and 9) adduction with hip extension beyond the midline. Myoelectric signals were taken up by Lec Tec surface electrodes connected to a 6-channel Lynx electromyographic signal amplifier coupled with a computer equipped with a model CAD 10/26 analogue digital conversion board and with a specific software for signal recording and analysis. We observed weak gastrocnemius muscle activity for all movements studied. In the case of gluteus maximus, the most important potentials were observed for movement 2, while for the remaining movements the actions were of reasonable intensity. Compared to gluteus, gastrocnemius was less required for all movements.

  6. The High-Pull Exercise: A Comparison Between a VersaPulley Flywheel Device and the Free Weight.

    PubMed

    Núñez, F Javier; Suarez-Arrones, Luis J; Cater, Paul; Mendez-Villanueva, Alberto

    2017-04-01

    The aim of this study was to examine the kinematics and kinetics (force, velocity, and acceleration) and blood lactate concentration with the VersaPulley (VP) device in comparison with free-weight (FW) exercise at a similar external load. Fifteen rugby players randomly performed 2 training sessions of 6 sets of 6 repetitions with 20 s of recovery between sets of the high-pull exercise with the VP and the FW. The training sessions were separated by 72 h. Barbell displacement (cm), peak velocity (m/s), peak acceleration (m/s(2)), mean propulsive velocity (m/s), mean propulsive acceleration (m/s(2)), propulsive phase (%), and mean and maximal force (N) were continuously recorded during each repetition. Blood lactate concentration was measured after each training session (end) and 3 min and 5 min later. Barbell displacement (+4.8%, small ES), peak velocity (+4.5% small ES), mean propulsive acceleration (+8.8%, small ES), and eccentric force (+26.7, large ES) were substantially higher with VP than with FW. Blood lactate concentration was also greater after the VP exercise (end +32.9%, 3 min later +36%, 5 min later +33.8%; large ES). Maximal concentric force was substantially higher with FW than VP during the 6th set (+6.4%, small ES). In the cohort and exercise investigated in the current study, VP training can be considered an efficient training device to induce an accentuated eccentric overload and augmented metabolic demands (ie, blood lactate concentration).

  7. A magnetic emergency release system for halo traction.

    PubMed

    Augsburger, Sam; White, Hank; Iwinski, Henry; Tylkowski, Chester M

    2010-01-01

    A magnetic emergency release system was developed for use in halo traction systems. Commercially available rare earth mounting magnets, with selected weight-carrying capacities, along with ferromagnetic receptacles, were used in line between halos and overhead pulleys to both carry the prescribed traction force and provide an emergency release in the event of excessive applied force due to a transportation accident and/or sudden application of full body weight when using overhead walkers equipped with traction systems. The magnet-receptacle pairs were calibrated with an in-line digital scale. Load rate dependencies were noted, indicating that prescribed magnet-receptacle pairs should be chosen to carry at least 110% body weight. This weight capacity is reduced to approximately 88% of body weight during higher loading rates, such as transportation accidents and accidental falls.

  8. Effect of laceration and trimming of a tendon on the coefficient of friction along the A2 pulley: an in vitro study on turkey tendon.

    PubMed

    Hajipour, L; Gulihar, A; Dias, J

    2010-08-01

    We carried out lacerations of 50%, followed by trimming, in ten turkey flexor tendons in vitro and measured the coefficient of friction at the tendon-pulley interface with loads of 200 g and 400 g and in 10 degrees , 30 degrees, 50 degrees and 70 degrees of flexion. Laceration increased the coefficient of friction from 0.12 for the intact tendon to 0.3 at both the test loads. Trimming the laceration reduced the coefficient of friction to 0.2. An exponential increase in the gliding resistance was found at 50 degrees and 70 degrees of flexion (p = 0.02 and p = 0.003, respectively) following trimming compared to that of the intact tendon. We concluded that trimming partially lacerated flexor tendons will reduce the gliding resistance at the tendon-pulley interface, but will lead to fragmentation and triggering of the tendon at higher degrees of flexion and loading. We recommend that higher degrees of flexion be avoided during early post-operative rehabilitation following trimming of a flexor tendon.

  9. Brain aromatase (cyp19a1b) and gonadotropin releasing hormone (gnrh2 and gnrh3) expression during reproductive development and sex change in black sea bass (Centropristis striata).

    PubMed

    Breton, Timothy S; DiMaggio, Matthew A; Sower, Stacia A; Berlinsky, David L

    2015-03-01

    Teleost fish exhibit diverse reproductive strategies, and some species are capable of changing sex. The influence of many endocrine factors, such as gonadal steroids and neuropeptides, has been studied in relation to sex change, but comparatively less research has focused on gene expression changes within the brain in temperate grouper species with non-haremic social structures. The purpose of the present study was to investigate gonadotropin releasing hormone (GnRH) and brain aromatase (cyp19a1b) gene expression patterns during reproductive development and sex change in protogynous (female to male) black sea bass (Centropristis striata). Partial cDNA fragments for cyp19a1b and eef1a (a reference gene) were identified, and included with known gnrh2 and gnrh3 sequences in real time quantitative PCR. Elevated cyp19a1b expression was evident in the olfactory bulbs, telencephalon, optic tectum, and hypothalamus/midbrain region during vitellogenic growth, which may indicate changes in the brain related to neurogenesis or sexual behavior. In contrast, gnrh2 and gnrh3 expression levels were largely similar among gonadal states, and all three genes exhibited stable expression during sex change. Although sex change in black sea bass is not associated with dramatic changes in GnRH or cyp19a1b gene expression among brain regions, these genes may mediate processes at other levels, such as within individual hypothalamic nuclei, or through changes in neuron size, that warrant further research.

  10. ARED Pulley and Rope

    NASA Image and Video Library

    2010-09-09

    ISS024-E-014009 (9 Sept. 2010) --- NASA astronaut Tracy Caldwell Dyson, Expedition 24 flight engineer, works with the advanced Resistive Exercise Device (aRED) in the Tranquility node of the International Space Station.

  11. Mi Tercer Libro de Maquinas Simples: La Rueda y la Polea. Escuela Intermedia Grados 7, 8 y 9 (My Third Book of Simple Machines: The Wheel and the Pulley. Intermediate School Grades 7, 8, and 9).

    ERIC Educational Resources Information Center

    Alvarado, Patricio R.; Montalvo, Luis

    This is the third book in a five-book physical science series on simple machines. The books are designed for Spanish-speaking junior high school students. This volume explains principles governing wheels and pulleys by suggesting experiments and posing questions concerning drawings in the book which illustrate the scientific principles. Friction…

  12. The relationship of trigger finger and flexor tendon volar migration after carpal tunnel release.

    PubMed

    Lee, S K; Bae, K W; Choy, W S

    2014-09-01

    It has been suggested that the increased frequency of trigger finger (TF) after carpal tunnel release (CTR) may be caused by the volar migration of the flexor tendons at the wrist altering the tendon biomechanics at the A1 pulley. This hypothesis has not been validated. We performed pre- and post-operative ultrasonography (USG) on the affected wrists of 92 patients who underwent CTR. Pre-operative USG was performed in neutral with no tendon loading; post-operative USG was performed in neutral unloaded and in various positions of wrist flexion whilst loading the flexor tendons with gripping. The mean volar migration of the flexor tendons after CTR was 2.2 (SD 0.4) mm in the unloaded neutral position. It was 1.8 (SD 0.4) mm in patients who did not develop TF and 2.5 (SD 0.5) mm in those who did (p = 0.0067). In loaded wrist flexion, the mean volar migration of flexor tendons after CTR in patients who did not develop TF and those who did was 2.1 and 3.0 mm in 0° flexion; 3.2 and 3.9 mm in 15° flexion; 4.3 and 5.1 mm in 30° flexion; and 4.9 and 5.8 mm in 45° flexion, respectively. There were significant differences between patients with and without TF at each flexion angle. Our data indicate that patients with greater volar migration of the flexor tendons after CTR are more likely to develop TF. This conclusion supports the hypothesis that the occurrence of TF after CTR may be caused by the bowstringing effects of the flexor tendons. © The Author(s) 2013.

  13. Strange bedfellows - A deep-water hermatypic coral reef superimposed on a drowned barrier island; Southern Pulley Ridge, SW Florida platform margin

    USGS Publications Warehouse

    Jarrett, B.D.; Hine, A.C.; Halley, R.B.; Naar, D.F.; Locker, S.D.; Neumann, A.C.; Twichell, D.; Hu, C.; Donahue, B.T.; Jaap, W.C.; Palandro, D.; Ciembronowicz, K.

    2005-01-01

    The southeastern component of a subtle ridge feature extending over 200 km along the western ramped margin of the south Florida platform, known as Pulley Ridge, is composed largely of a non-reefal, coastal marine deposit. Modern biostromal reef growth caps southern Pulley Ridge (SPR), making it the deepest hermatypic reef known in American waters. Subsurface ridge strata are layered, lithified, and display a barrier island geomorphology. The deep-water reef community is dominated by platy scleractinian corals, leafy green algae, and coralline algae. Up to 60% live coral cover is observed in 60-75 m of water, although only 1-2% of surface light is available to the reef community. Vertical reef accumulation is thin and did not accompany initial ridge submergence during the most recent sea-level rise. The delayed onset of reef growth likely resulted from several factors influencing Gulf waters during early stages of the last deglaciation (???14 kyr B.P.) including; cold, low-salinity waters derived from discrete meltwater pulses, high-frequency sea-level fluctuations, and the absence of modern oceanic circulation patterns. Currently, reef growth is supported by the Loop Current, the prevailing western boundary current that impinges upon the southwest Florida platform, providing warm, clear, low-nutrient waters to SPR. The rare discovery of a preserved non-reefal lowstand shoreline capped by rich hermatypic deep-reef growth on a tectonically stable continental shelf is significant for both accurate identification of late Quaternary sea-level position and in better constraining controls on the depth limits of hermatypic reefs and their capacity for adaptation to extremely low light levels. ?? 2004 Elsevier B.V. All rights reserved.

  14. On the simulation and theory of polymer dynamics in sieving media: Friction, molecular pulleys, Brownian ratchets and polymer scission

    NASA Astrophysics Data System (ADS)

    Kenward, Martin

    the middle of the molecules. In chapter 3 we use some of the concepts and results from chapters 1 and 2 to explore the problem of a polymer chain migrating under the influence of an external force (or fluid flow) through a molecular obstacle course. These polymers collide with either fixed obstacles (or other polymers) and can be trapped in meta-stable long-lived, pulley-like conformations. This method can be used to separate polymers by molecular weight. We use both MD simulations and a general classical theory for the collisions to explore several different collision regimes. We also show that a classic experimental result, the formation of so-called V-shaped states, can occur in single polymer collision events, contrary to the popular assumption that it was necessary for a polymer to collide with multiple polymers. In chapter 4 we build on the results and ideas from the first three chapters and examine another phenomenon related to polymer transport, that of (Brownian) ratchets. A ratchet is essentially a method to rectify the thermal noise in a system in order to perform work, for example, to generate net transport. We use our MD simulations to examine the behaviour of polymers in the presence of an asymmetric saw tooth ratchet potential. We also show that existing ratchet models, where the ratchet widths are on the order of a polymer gyration radius, neglect an important effect of chain relaxation and thus underestimate optimal operating parameters. We propose and derive equations illustrating a new operational mode for a ratchet which inherently uses the deformation of polymer chains induced by the application of a ratcheting potential. We present a simple mathematical expression to incorporate time-dependent diffusion coefficients D (t) into ratchets. The final chapter presents work done in collaboration with Annelise Barron's group at Northwestern University and examines the breaking of polymer chains in extensional flow fields as a method to systematically

  15. A Novel Loading Method for Doxycycline Liposomes for Intracellular Drug Delivery: Characterization of In Vitro and In Vivo Release Kinetics and Efficacy in a J774A.1 Cell Line Model of Mycobacterium smegmatis Infection

    PubMed Central

    Marcus, Sarah A.; Talaat, Adel M.; KuKanich, Butch K.; Sullivan, Ruth; Krugner-Higby, Lisa A.; Heath, Timothy D.

    2015-01-01

    Doxycycline (doxy) is used in treating intracellular and extracellular infections. Liposomal (LE) antibiotics allow low-frequency dosing and extended efficacy compared with standard (STD) formulations. We developed a novel sulfuric acid–loading method for doxycycline liposomes (LE-doxy). We hypothesized that a single s.c. injection of LE-doxy would be detectable in serum for at least 2 weeks at concentrations equal to or better than STD-doxy and would be bactericidal in an in vitro Mycobacterium smegmatis infection of J774A.1 macrophage cells. Liposomes were encapsulated by sulfuric acid gradient loading, and release kinetics were performed in vitro and in vivo. LE-doxy made using 8.25 mg/ml doxycycline loaded for 24 hours achieved 97.77% capture in 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 43.87% in sphingomyelin (sphing). Rats were injected s.c. with 50 mg/kg LE-doxy or 5 mg/kg STD-doxy, and serial blood samples were collected. Pharmacokinetics were analyzed using high-performance liquid chromatography. Liver and injection site skin samples were collected at euthanasia (4 weeks postinjection). Minimal histologic tissue reactions occurred after injection of STD (nonliposomal), DPPC, or sphing-doxy. DPPC-doxy had slightly faster in vitro leakage than sphing liposomes, although both were detectable at 264 hours. The mean residence time for DPPC was the highest (111.78 hours), followed by sphing (56.00 hours) and STD (6.86 hours). DPPC and sphing-doxy were detectable at 0.2 μg/ml in serum at 336 hours postadministration. LE-doxy was not toxic to J774A.1 cells in vitro and produced inhibition of viable Mycobacterium smegmatis at 24 and 48 hours. LE-doxy will require further testing in in vivo infection models. PMID:26033620

  16. Chemiluminescence from the Ba((3)P)+N(2)O-->BaO(A (1)Sigma(+))+N(2) reaction: Collision energy effects on the product rotational alignment and energy release.

    PubMed

    Rossa, Maximiliano; Rinaldi, Carlos A; Ferrero, Juan C

    2010-01-21

    Both fully dispersed unpolarized and polarized chemiluminescence spectra from the Ba((3)P)+N(2)O reaction have been recorded under hyperthermal laser-ablated atomic beam-Maxwellian gas conditions at three specific average collision energies E(c) in the range of 4.82-7.47 eV. A comprehensive analysis of the whole data series suggests that the A (1)Sigma(+)-->X (1)Sigma(+) band system dominates the chemiluminescence. The polarization results revealed that the BaO(A (1)Sigma(+)) product rotational alignment is insensitive to its vibrational state upsilon(') at E(c)=4.82 eV but develops into an strong negative correlation between product rotational alignment and upsilon(') at 7.47 eV. The results are interpreted in terms of a direct mechanism involving a short-range, partial electron transfer from Ba((3)P) to N(2)O which is constrained by the duration of the collision, so that the reaction has a larger probability to occur when the collision time is larger than the time needed for N(2)O bending. The latter in turn determines that, at any given E(c), collinear reactive intermediates are preferentially involved when the highest velocity components of the corresponding collision energy distributions are sampled. Moreover, the data at 4.82 eV suggest that a potential barrier to reaction which favors charge transfer to bent N(2)O at chiefly coplanar geometries is operative for most of the reactive trajectories that sample the lowest velocity components. Such a barrier would arise from the relevant ionic-covalent curve crossings occurring in the repulsive region of the covalent potential Ba((3)P)cdots, three dots, centeredN(2)O((1)Sigma(+)); from this crossing the BaO(A (1)Sigma(+)) product may be reached through mixings in the exit channel with potential energy surfaces leading most likely to the spin-allowed b (3)Pi and a (3)Sigma(+) products. The variation with increasing E(c) of both the magnitude of the average BaO(A (1)Sigma(+)) rotational alignment and the BaO(A (1

  17. Transverse carpal ligament: its effect on flexor tendon excursion, morphologic changes of the carpal canal, and on pinch and grip strengths after open carpal tunnel release.

    PubMed

    Netscher, D; Mosharrafa, A; Lee, M; Polsen, C; Choi, H; Steadman, A K; Thornby, J

    1997-09-01

    A three-part study is described that examines postoperative weakness after open carpal tunnel release and investigates the role of the transverse carpal ligament in the digital flexor pulley system. The effect of this ligament on flexor tendon excursion is evaluated in a cadaver study. Magnetic resonance imaging analysis is used to determine whether division of the transverse carpal ligament promotes volar migration of the median nerve and flexor tendons. Finally, the effects of ligament division and various methods of transverse carpal ligament reconstruction on the return of grip and pinch strengths after open carpal tunnel release are evaluated. The authors were able to determine that transverse carpal ligament reconstruction, particularly the transposition flap repair technique, after open carpal tunnel release confers a mechanical advantage and that the transverse carpal ligament is an important pulley for flexor tendon excursion. Based on the magnetic resonance imaging studies, volar displacement of carpal contents is reduced in patients undergoing transverse carpal ligament reconstruction by means of a transposition flap compared with those undergoing no ligament reconstruction and those undergoing reconstruction using the palmar aponeurosis. Postoperative grip and pinch strength values for the transposition flap repair group surpassed those of the other two groups at 12 weeks.

  18. Microangiographic Comparison of the Effects of 3 Loop Pulley and 6 Strand Savage Tenorrhaphy Techniques on Equine Superficial Digital Flexor Tendon.

    PubMed

    Freeman, Kendra D; Barrett, Jennifer G; Youngstrom, Daniel W; White, Nathaniel A

    2015-08-01

    The 6-strand Savage (SSS) tenorrhaphy pattern is biomechanically superior to the commonly employed 3-loop pulley (3LP); however, its effects on intrinsic tendon vasculature remain unknown. The objective of this study was to compare perfusion of intrinsic vasculature of the equine superficial digital flexor tendon (SDFT) after 3LP and SSS tenorrhaphies. We hypothesized that the SSS technique would significantly decrease vascular perfusion compared to the 3LP technique. Ex vivo, randomized, paired design. Horses (n = 9) METHODS: Under general anesthesia, 9 pairs of forelimb SDFT were transected. Two tendons served as baseline control, the remainder had either SSS or 3LP tenorrhaphy performed. Horses were heparinized, euthanatized, and forelimbs perfused with barium sulfate solution were then fixed with formalin under tension. Tendons were transected every 5 mm and microangiographic images obtained. Microvascular analysis of sections proximal to, throughout, and distal to the tenorrhaphy was completed using a custom macro. Differences in vascular count were assessed using MANOVA. A significant reduction in the number of perfused vessels was seen for SSS compared with 3LP at 2 locations within the tenorrhaphy (P = .039 and P = .009). The SSS technique took on average 4.7 ± 0.9 times longer to place. The SSS technique causes an acute reduction in tendon perfusion compared to the 3LP, which may limit its clinical use. Further research is required to elucidate the clinical significance of this difference. © Copyright 2015 by The American College of Veterinary Surgeons.

  19. Syndactyly Release.

    PubMed

    Braun, Tara L; Trost, Jeffrey G; Pederson, William C

    2016-11-01

    Syndactyly is one of the most common congenital hand anomalies treated by pediatric plastic surgeons. Established principles of syndactyly separation dictate the timing and order of syndactyly release, with the goals of surgery being the creation of an anatomically normal webspace, tension-free closure of soft tissue, and return of function to the fingers. Numerous surgical methods have been described, many of which involve the use of local flaps to reconstruct the commissure and full-thickness skin grafts for coverage of raw areas. Recently, reconstructive techniques without the use of skin grafts have been devised, which work well for certain indications. Special considerations are described for complete, complex, and syndromic syndactylies. Outcomes for simple syndactyly release are typically good when surgical principles are followed, whereas complex syndactyly release tends to have less-favorable outcomes and more complications.

  20. Toggle release

    NASA Technical Reports Server (NTRS)

    Graves, Thomas J. (Inventor); Yang, Robert A. (Inventor); Brown, Christopher W. (Inventor)

    1989-01-01

    A pyrotechnic actuated structural release device 10 which is mechanically two fault tolerant for release. The device 10 comprises a fastener plate 11 and fastener body 12, each attachable to a different one of a pair of structures to be joined. The fastener plate 11 and body 12 are fastenable by a toggle 13 supported at one end on the fastener plate and mounted for universal pivotal movement thereon. At its other end which is received in a central opening in the fastener body 12 and adapted for limited pivotal movement therein the toggle 13 is restrained by three retractable latching pins 61 symmetrically disposed in equiangular spacing about the axis of the toggle 13 and positionable in latching engagement with an end fitting on the toggle. Each pin 61 is individually retractable by combustion of a pyrotechnic charge 77, the expanding gases of which are applied to a pressure receiving face 67 on the latch pin 61 to effect its retraction from the toggle. While retraction of all three pins 62 releases the toggle, the fastener is mechanically two fault tolerant since the failure of any single one or pair of the latch pins to retract results in an asymmetrical loading on the toggle and its pivotal movement to effect a release. An annular bolt 18 is mounted on the fastener plate 11 as a support for the socket mounting 30, 37 of the toggle whereby its selective axial movement provides a means for preloading the toggle.

  1. Delayed Case of Congenital Bilateral Trigger Thumb: A Case Report and Review of Literature

    PubMed Central

    Rekha, Y Bhanu

    2014-01-01

    Introduction: Congenital trigger thumb is an uncommon anomaly of children. Its management is controversial, ranging from observation to extensive surgical release. We report a case of delayed presentation of bilateral trigger thumb along with a brief review of past literature. Case Report: A six year old girl presented with fixed flexion deformity of interphalangeal joints of both thumbs and Notta’s nodules. It is diagnosed as trigger thumb and release of bilateral A1pulleys is done. But we found another constricting annular pulley just distal to A1. Only after splitting the distal pulley, we could get complete extension of interphalangeal joints. At two years follow-up, the child is free of complications. Conclusion: Splitting of A1 pulley alone may not be sufficient in few cases of trigger thumb which may require distal release too PMID:27298940

  2. Bioactive saponins and glycosides. IV. Four methyl-migrated 16,17-seco-dammarane triterpene gylcosides from Chinese natural medicine, hoveniae semen seu fructus, the seeds and fruit of Hovenia dulcis THUNB.: absolute stereostructures and inhibitory activity on histamine release of hovenidulciosides A1, A2, B1, and B2.

    PubMed

    Yoshikawa, M; Murakami, T; Ueda, T; Matsuda, H; Yamahara, J; Murakami, N

    1996-09-01

    Four bioactive methyl-migrated 16,17-seco-dammarane type triterpene glycosides called hovenidulciosides A1, A2, B1, and B2 were isolated from a Chinese natural medicine, Hoveniae Semen Seu Fructus, the seeds and fruit of Hovenia dulcis THUNB. (Rhamnaceae) together with hoduloside III and (+)-gallocatechin. The absolute stereostructures of hovenidulciosides A1, A2, B1, and B2 have been elucidated by chemical and physicochemical evidence. All were found to inhibit the histamine release from rat peritoneal exudate cells induced by compound 48/80 and calcium ionophore A-23187.

  3. The Hook and Release Technique During Enucleation Surgery.

    PubMed

    Jordan, David R; Stoica, Bazil; Dutton, Jonathan J

    2017-01-05

    To describe the results and potential benefit of direct muscle release from the globe during enucleation surgery without identifying sutures in the rectus muscle insertion sites, a technique referred to as the hook and release technique. Single center, retrospective chart review of patients who underwent enucleation with direct removal of the rectus muscles without identifying sutures in their insertion sites between January 2011 and September 2015 was carried out. The inclusion criteria were primary enucleation without previous strabismus surgery, retinal detachment surgery, or orbital surgery that entered the fibrous connective tissue framework. Forty charts of enucleated patients that had direct release of their extraocular muscles without identifying sutures before releasing them from the globe were identified and reviewed. The primary outcome measure was intraoperative or immediate postoperative complications. This retrospective chart review was performed with research ethics board approval and in compliance with the Declaration of Helsinki. Data show that following the hook and release technique, the rectus muscles were easily located and reconnected to the orbital implant wrap. The oblique muscles were not reattached. In each of the 40 patients, the 4 rectus muscles were easily located by gently applying traction anteriorly at the conjunctiva/Tenons' edge using double-pronged skin hooks. There was no instance of a lost or slipped muscle following the hook and release technique. The hook and release technique is a simple and efficient method to remove the 4 rectus muscles from the globe and still easily locate them. They are not "lost" and do not "slip out of position" but held in place by the orbital connective tissue framework and the extraocular muscle pulley system. This technique has been very helpful teaching resident staff how to do enucleation surgery as it avoids the more time consuming placement of double-armed locking sutures through the rectus

  4. Atomic-resolution studies of epitaxial strain release mechanisms in L a1.85S r0.15Cu O4 /L a0.67C a0.33Mn O3 superlattices

    NASA Astrophysics Data System (ADS)

    Biškup, N.; Das, S.; Gonzalez-Calbet, J. M.; Bernhard, C.; Varela, M.

    2015-05-01

    In this paper we present an atomic-resolution electron microscopy study of superlattices (SLs) where the colossal magnetoresistant manganite L a0.67C a0.33Mn O3 (LCMO) and the high critical temperature superconducting cuprate L a1.85S r0.15Cu O4 (LSCO) are combined. Although good quality epitaxial growth can be achieved, both the choice of substrate and the relatively large lattice mismatch between these materials (around 2%) have a significant impact on the system properties [Phys. C 468, 991 (2008), 10.1016/j.physc.2008.05.001; Nature (London) 394, 453 (1998), 10.1038/28810]. Our samples, grown by pulsed laser deposition, are epitaxial and exhibit high structural quality. By means of cutting-edge electron microscopy and spectroscopy techniques we still find that the epitaxial strain is accommodated by a combination of defects, such as interface steps and antiphase boundaries in the manganite. These defects result in inhomogeneous strain fields through the samples. Also, some chemical inhomogeneities are detected, up to the point that novel phases nucleate. For example, at the LCMO/LSCO interface the AB O3 -type manganite adopts a tetragonal LSCO-like structure forming localized layers that locally resemble the composition of L a2 /3C a4 /3Mn O4 . Structural distortions are detected in the cuprate as well, which may extend over lateral distances of several unit cells. Finally, we also analyze the influence of the substrate-induced strain by examining superlattices grown on two different substrates: (LaAlO3) 0.3(Sr2AlTaO6 ) 0.7 (LSAT) and LaSrAl O4 (LSAO). We observe that SLs grown on LSAT, which are nonsuperconducting, present reduced values of the c axis compared to superlattices grown on LSAO (which are fully superconducting). This finding points to the fact that the proper distance between copper planes in LSCO is essential in obtaining superconductivity in cuprates.

  5. Release Fraction Evaluation

    SciTech Connect

    Bamberger, Judith A.; Glissmeyer, John A.

    2004-01-01

    This document presents results of experiments conducted to measure release fractions during certain tank retrieval processes. The tests were performed in a 1/4 scale model of a waste storage tank. The retrieval processes simulated were: (1) Discharging liquid or slurry from the mouth of a vertically oriented two-in. Schedule 40 pipe. The discharging material was in free-fall from the mouth of the pipe near the top of the tank into a liquid or slurry pool at the bottom of the tank. (2) The jet from a 9/16-in.-diameter nozzle transferring liquid or slurry waste from one side of the tank to the other. The discharging liquid was aimed at the opposite side of the tank from the nozzle and either impacted the tank wall or fell into a liquid or slurry pool in the bottom of the tank. (3) A high pressure fan jet of liquid striking a steel plate or simulated waste from a stand-off distance of a few inches. For each process, a water-soluble fluorescent dye was added to the liquid fraction as a tracer. Kaolin clay was used to represent the solids. The tank was covered and there was no forced ventilation in the tank during the tests. Six air samples were collected during each test. The air samples were collected at fixed positions in the tank. The air sample filters were dried and weighed to determine the solids collection. The fluorescent dye was then leached from each filter and quantified with a fluorometer to determine the collection of liquid. Samples of the slurry and liquid simulants were also collected to determine the quantities of simulant used in each test. To calculate the release fraction, the quantity collected on each air sample was adjusted for the fraction of the tank volume sampled and divided by the quantity of material exposed in the simulation. The method was not as sensitive for the solids content as it was for the liquid content, but in those instances where a solids release fraction was determined, it was in relatively good agreement with that of the

  6. Reusable Release Mechanism

    NASA Technical Reports Server (NTRS)

    Bunker, J. W.; Ritchie, R. S.

    1984-01-01

    Slider release mechanism reusable. Bears heavy loads while latched, yet gives smooth release motion. Release effected by explosively driving perpendicular slider out of engagement with load-bearing shank. Device has potential industrial applications such as emergency release of lifting cables from helicopters, cranes and hoists.

  7. The conservative treatment of Trigger Thumb using Graston Techniques and Active Release Techniques®

    PubMed Central

    Howitt, Scott; Wong, Jerome; Zabukovec, Sonja

    2006-01-01

    Objective To detail the progress of a patient with unresolved symptoms of Trigger thumb who underwent a treatment plan featuring Active Release Technique (ART) and Graston Technique. Clinical Features The most important feature is painful snapping or restriction of movement, most notably in actively extending or flexing the digit. The cause of this flexor tendinopathy is believed to be multi-factorial including anatomical variations of the pulley system and biomechanical etiologies such as exposure to shear forces and unaccustomed activity. Conventional treatment aims at decreasing inflammation through corticosteroid injection or surgically removing imposing tissue. Intervention and Outcome The conservative treatment approach utilized in this case involved Active Release Technique (ART®) and Graston Technique (GT). An activity specific rehabilitation protocol was employed to re-establish thumb extensor strength and ice was used to control pain and any residual inflammation. Outcome measures included subjective pain ratings with range of motion and motion palpation of the first right phalangeal joint. Objective measures were made by assessing range of motion. Conclusion A patient with trigger thumb appeared to be relieved of his pain and disability after a treatment plan of GT and ART. PMID:17549185

  8. Delayed simultaneous release mechanism

    NASA Technical Reports Server (NTRS)

    Moyer, X. W.; Webb, J. B. (Inventor)

    1973-01-01

    The disclosed appendage release mechanism is particularly adapted for use with spacecraft operating with despin mechanisms and releasable appendages. It includes a flexible loop and a number of appendage releasing devices which are attached to the flexible loop. The appendage releasing devices are made up of piston-cams and ball latches which hold the appendages as long as the flexible loop is maintained in a taut condition, but which release the appendages upon relaxation of the flexible loop. The flexible loop remains taut as long as the despin weights remain attached, but relaxes when the despin weights are released.

  9. A1C test

    MedlinePlus

    HbA1C test; Glycated hemoglobin test; Glycohemoglobin test; Hemoglobin A1C; Diabetes - A1C; Diabetic - A1C ... gov/pubmed/26696680 . Chernecky CC, Berger BJ. Glycosylated hemoglobin (GHb, glycohemoglobin, glycated hemoglobin, HbA1a, HbA1b, HbA1c - blood. ...

  10. [Lateral retinacular release].

    PubMed

    Verdonk, P; Bonte, F; Verdonk, R

    2008-09-01

    This overview of numerous studies discusses, based on short-term and long-term results, which diagnoses are indications for lateral retinacular release. No significant differences in outcome between arthroscopic and open lateral release could be documented. Isolated lateral release offers a good success rate for treating a stable patella with excessive lateral pressure. In patellar instability, the results are less favorable in long-term follow-up evaluation. Hyperlaxity with hypermobility of the patella is an absolute contraindication. Lateral release provides only temporary benefit for patellofemoral osteoarthritis. Proximal and/or distal realignment of the extensor mechanism gives better results than isolated lateral release.

  11. Aspartate release from rat hippocampal synaptosomes.

    PubMed

    Bradford, S E; Nadler, J V

    2004-01-01

    Certain excitatory pathways in the rat hippocampus can release aspartate along with glutamate. This study utilized rat hippocampal synaptosomes to characterize the mechanism of aspartate release and to compare it with glutamate release. Releases of aspartate and glutamate from the same tissue samples were quantitated simultaneously. Both amino acids were released by 25 mM K(+), 300 microM 4-aminopyridine (4-AP) and 0.5 and 1 microM ionomycin in a predominantly Ca(2+)-dependent manner. For a roughly equivalent quantity of glutamate released, aspartate release was significantly greater during exposure to elevated [K(+)] than to 4-AP and during exposure to 0.5 than to 1 microM ionomycin. Aspartate release was inefficiently coupled to P/Q-type voltage-dependent Ca(2+) channels and was reduced by KB-R7943, an inhibitor of reversed Na(+)/Ca(2+) exchange. In contrast, glutamate release depended primarily on Ca(2+) influx through P/Q-type channels and was not significantly affected by KB-R7943. Pretreatment of the synaptosomes with tetanus toxin and botulinum neurotoxins C and F reduced glutamate release, but not aspartate release. Aspartate release was also resistant to bafilomycin A(1), an inhibitor of vacuolar H(+)-ATPase, whereas glutamate release was markedly reduced. (+/-) -Threo-3-methylglutamate, a non-transportable competitive inhibitor of excitatory amino acid transport, did not reduce aspartate release. Niflumic acid, a blocker of Ca(2+)-dependent anion channels, did not alter the release of either amino acid. Exogenous aspartate and aspartate recently synthesized from glutamate accessed the releasable pool of aspartate as readily as exogenous glutamate and glutamate recently synthesized from aspartate accessed the releasable glutamate pool. These results are compatible with release of aspartate from either a vesicular pool by a "non-classical" form of exocytosis or directly from the cytoplasm by an as-yet-undescribed Ca(2+)-dependent mechanism. In either case

  12. ELECTROMAGNETIC RELEASE MECHANISM

    DOEpatents

    Michelson, C.

    1960-09-13

    An electromagnetic release mechanism is offered that may be used, for example, for supporting a safety rod for a nuclear reactor. The release mechanism is designed to have a large excess holding force and a rapid, uniform, and dependable release. The fast release is accomplished by providing the electromagnet with slotttd polts separated by an insulating potting resin, and by constructing the poles with a ferro-nickel alloy. The combination of these two features materially reduces the eddy current power density whenever the magnetic field changes during a release operation. In addition to these features, the design of the armature is such as to provide ready entrance of fluid into any void that might tend to form during release of the armature. This also improves the release time for the mechanism. The large holding force for the mechanism is accomplished by providing a small, selected, uniform air gap between the inner pole piece and the armature.

  13. Extended-release oxybutynin.

    PubMed

    Comer, A M; Goa, K L

    2000-02-01

    Extended-release oxybutynin (Ditropan XL) uses an osmotic system (OROS) to deliver a controlled amount of oxybutynin chloride into the gastrointestinal tract over a 24-hour period when taken once daily. Oxybutynin binds to M3 muscarinic receptors on the detrusor muscle of the bladder, preventing acetylcholinergic activation and relaxing the muscle. Mean peak plasma concentrations are lower with extended-release oxybutynin 15mg once daily than with conventional immediate-release oxybutynin 5mg taken 3 times daily. Relative bioavailabilities of parent drug and metabolite N-desethoxybutynin are 153 and 69%, respectively, for extended-release oxybutynin when compared with immediate-release oxybutynin. In short (< or =6 weeks) randomised, double-blind clinical trials of patients with detrusor instability, extended-release oxybutynin 5 to 30mg once daily significantly reduced the mean weekly number of urge incontinence episodes by 84 to 90%. Extended-release oxybutynin had similar efficacy to immediate-release oxybutynin. Adverse events reported by patients taking extended-release oxybutynin were dose-related anticholinergic effects, most frequently dry mouth, somnolence, constipation, blurred vision and dizziness. A large noncomparative study demonstrated that approximately two thirds of the patients prescribed extended-release oxybutynin for detrusor instability were still taking the medication 6 months later.

  14. Multicomponent Implant Releasing Dexamethasone

    NASA Astrophysics Data System (ADS)

    Nikkola, L.; Vapalahti, K.; Ashammakhi, N.

    2008-02-01

    Several inflammatory conditions are usually treated with corticosteroids. There are various problems like side effects with traditional applications of steroids, e.g. topical, or systemic routes. Local drug delivery systems have been studied and developed to gain more efficient administration with fewer side effects. Earlier, we reported on developing Dexamethasone (DX) releasing biodegradable fibers. However, their drug release properties were not satisfactory in terms of onset of drug release. Thus, we assessed the development of multicomponent (MC) implant to enhance earlier drug release from such biodegradable fibers. Poly (lactide-co-glycolide) (PLGA) and 2 wt-% and 8 wt-% DX were compounded and extruded with twin-screw extruder to form of fibers. Some of the fibers were sterilized to obtain a change in drug release properties. Four different fiber classes were studied: 2 wt-%, 8 wt-%, sterilized 2 wt-%, and sterilized 8 wt-%. 3×4 different DX-releasing fibers were then heat-pressed to form one multicomponent rod. Half of the rods where sterilized. Drug release was measured from initial fibers and multicomponent rods using a UV/VIS spectrometer. Shear strength and changes in viscosity were also measured. Drug release studies showed that drug release commenced earlier from multicomponent rods than from component fibers. Drug release from multicomponent rods lasted from day 30 to day 70. The release period of sterilized rods extended from day 23 to day 57. When compared to the original component fibers, the drug release from MC rods commenced earlier. The initial shear strength of MC rods was 135 MPa and decreased to 105 MPa during four weeks of immersion in phosphate buffer solution. Accordingly, heat pressing has a positive effect on drug release. After four weeks in hydrolysis, no disintegration was observed.

  15. Dendritic Release of Neurotransmitters.

    PubMed

    Ludwig, Mike; Apps, David; Menzies, John; Patel, Jyoti C; Rice, Margaret E

    2016-12-06

    Release of neuroactive substances by exocytosis from dendrites is surprisingly widespread and is not confined to a particular class of transmitters: it occurs in multiple brain regions, and includes a range of neuropeptides, classical neurotransmitters, and signaling molecules, such as nitric oxide, carbon monoxide, ATP, and arachidonic acid. This review is focused on hypothalamic neuroendocrine cells that release vasopressin and oxytocin and midbrain neurons that release dopamine. For these two model systems, the stimuli, mechanisms, and physiological functions of dendritic release have been explored in greater detail than is yet available for other neurons and neuroactive substances. © 2017 American Physiological Society. Compr Physiol 7:235-252, 2017.

  16. Release the Body, Release the Mind.

    ERIC Educational Resources Information Center

    Stoner, Martha Goff

    1998-01-01

    A college English teacher describes the anxiety and resentment of students during in-class writing assignments and the successful classroom use of meditation and body movement. Movement seemed to relax the students, change their attitudes, and release their creative impulses to write. Implications related to the body-mind connection are pondered.…

  17. Morphology of Gas Release in Physical Simulants

    SciTech Connect

    Daniel, Richard C.; Burns, Carolyn A.; Crawford, Amanda D.; Hylden, Laura R.; Bryan, Samuel A.; MacFarlan, Paul J.; Gauglitz, Phillip A.

    2014-07-03

    This report documents testing activities conducted as part of the Deep Sludge Gas Release Event Project (DSGREP). The testing described in this report focused on evaluating the potential retention and release mechanisms of hydrogen bubbles in underground radioactive waste storage tanks at Hanford. The goal of the testing was to evaluate the rate, extent, and morphology of gas release events in simulant materials. Previous, undocumented scoping tests have evidenced dramatically different gas release behavior from simulants with similar physical properties. Specifically, previous gas release tests have evaluated the extent of release of 30 Pa kaolin and 30 Pa bentonite clay slurries. While both materials are clays and both have equivalent material shear strength using a shear vane, it was found that upon stirring, gas was released immediately and completely from bentonite clay slurry while little if any gas was released from the kaolin slurry. The motivation for the current work is to replicate these tests in a controlled quality test environment and to evaluate the release behavior for another simulant used in DSGREP testing. Three simulant materials were evaluated: 1) a 30 Pa kaolin clay slurry, 2) a 30 Pa bentonite clay slurry, and 3) Rayleigh-Taylor (RT) Simulant (a simulant designed to support DSGREP RT instability testing. Entrained gas was generated in these simulant materials using two methods: 1) application of vacuum over about a 1-minute period to nucleate dissolved gas within the simulant and 2) addition of hydrogen peroxide to generate gas by peroxide decomposition in the simulants over about a 16-hour period. Bubble release was effected by vibrating the test material using an external vibrating table. When testing with hydrogen peroxide, gas release was also accomplished by stirring of the simulant.

  18. A1C Test

    MedlinePlus

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Hemoglobin A1c Share this page: Was this page helpful? Also known as: A1c; HbA1c; Glycohemoglobin; Glycated Hemoglobin; Glycosylated Hemoglobin Formal name: Hemoglobin A1c Related tests: ...

  19. DSCOVR Public Release Statement

    Atmospheric Science Data Center

    2016-11-23

    ... DSCOVR Public Release Statement Wednesday, July 20, 2016 The Deep Space Climate Observatory (DSCOVR) is a ... is limited to the near infrared solar reflected signal. The fourth detector is a high signal-to-noise photodiode spanning UV, Visible, and ...

  20. The 2017 Release Cloudy

    NASA Astrophysics Data System (ADS)

    Ferland, G. J.; Chatzikos, M.; Guzmán, F.; Lykins, M. L.; van Hoof, P. A. M.; Williams, R. J. R.; Abel, N. P.; Badnell, N. R.; Keenan, F. P.; Porter, R. L.; Stancil, P. C.

    2017-10-01

    We describe the 2017 release of the spectral synthesis code Cloudy, summarizing the many improvements to the scope and accuracy of the physics which have been made since the previous release. Exporting the atomic data into external data files has enabled many new large datasets to be incorporated into the code. The use of the complete datasets is not realistic for most calculations, so we describe the limited subset of data used by default, which predicts significantly more lines than the previous release of Cloudy. This version is nevertheless faster than the previous release, as a result of code optimizations. We give examples of the accuracy limits using small models, and the performance requirements of large complete models. We summarize several advances in the H- and He-like iso-electronic sequences and use our complete collisional-radiative models to establish the densities where the coronal and local thermodynamic equilibrium approximations work.

  1. Rad-Release

    ScienceCinema

    None

    2016-07-12

    The R&D 100 Award winning Rad-Release Chemical Decontamination Technology is a highly effective (up to 99% removal rate), affordable, patented chemical-foam-clay decontamination process tailored to specific radiological and metal contaminants, which is applicable to a wide variety of substrates. For more information about this project, visit http://www.inl.gov/rd100/2011/rad-release/

  2. Rad-Release

    SciTech Connect

    2011-01-01

    The R&D 100 Award winning Rad-Release Chemical Decontamination Technology is a highly effective (up to 99% removal rate), affordable, patented chemical-foam-clay decontamination process tailored to specific radiological and metal contaminants, which is applicable to a wide variety of substrates. For more information about this project, visit http://www.inl.gov/rd100/2011/rad-release/

  3. Advanced release technologies program

    NASA Technical Reports Server (NTRS)

    Purdy, Bill

    1994-01-01

    The objective of the ARTS program was to develop lighter and less expensive spacecraft ordnance and release systems that answer to the requirements of a wide variety of spacecraft applications. These improvements were to be evaluated at the spacecraft system level, as it was determined that there were substantial system-level costs associated with the present ordnance and release subsystems. New, better devices were to be developed, then flight qualified, then integrated into a flight experiment in order to prove the reliability required for their subsequent use on high-reliability spacecraft. The secondary goal of the program was to quantify the system-level benefits of these new subsystems based upon the development program results. Three non-explosive release mechanisms and one laser-diode-based ordnance system were qualified under the program. The release devices being developed were required to release high preloads because it is easier to scale down a release mechanism than to scale it up. The laser initiator developed was required to be a direct replacement for NASA Standard Initiators, since these are the most common initiator in use presently. The program began in October, 1991, with completion of the flight experiment scheduled for February, 1994. This paper provides an overview of the ARTS program, discusses the benefits of using the ARTS components, introduces the new components, compares them with conventional systems and each other, and provides recommendations on how best to implement them.

  4. Pulley With Active Antifriction Actuator And Control

    NASA Technical Reports Server (NTRS)

    Ih, Che-Hang C.; Vivian, Howard C.

    1994-01-01

    Torque actuator and associated control system minimizes effective friction of rotary bearing. Motor exerts compensating torque in response to feedback from external optical sensor. Compensation torque nearly cancels frictional torque of shaft bearings. Also useful in reducing bearing friction in gyro-scopes, galvanometers, torquemeters, accelerometers, earth-motion detectors, and balances.

  5. A fluoride release-adsorption-release system applied to fluoride-releasing restorative materials.

    PubMed

    Suljak, J P; Hatibovic-Kofman, S

    1996-09-01

    This investigation compared the initial fluoride release and release following refluoridation of three resin-modified glass-ionomer cements (Photac-Fil Applicap, Vitremer, and Fuji II LC) and a new polyacid-modified resin composite material (Dyract). After daily flouride release was measured for 8 days, specimens were refluoridated in 1,000-ppm solutions of fluoride ion for 10 minutes and fluoride release was measured for 5 days. Two further 5-day refluoridation-release periods were carried out. All materials released fluoride initially. Photac released the most; Dyract released the least. Initial release was greatest over the first few days. All materials released significantly more fluoride for 24 to 48 hours after refluoridation. Less fluoride was released with each successive refluoridation for the three glass-ionomer cements. The release from the Dyract compomer remained at a comparatively constant and significantly lower level following each refluoridation.

  6. RAVEN Beta Release

    SciTech Connect

    Rabiti, Cristian; Alfonsi, Andrea; Cogliati, Joshua Joseph; Mandelli, Diego; Kinoshita, Robert Arthur; Wang, Congjian; Maljovec, Daniel Patrick; Talbot, Paul William

    2016-02-01

    This documents the release of the Risk Analysis Virtual Environment (RAVEN) code. A description of the RAVEN code is provided, and discussion of the release process for the M2LW-16IN0704045 milestone. The RAVEN code is a generic software framework to perform parametric and probabilistic analysis based on the response of complex system codes. RAVEN is capable of investigating the system response as well as the input space using Monte Carlo, Grid, or Latin Hyper Cube sampling schemes, but its strength is focused toward system feature discovery, such as limit surfaces, separating regions of the input space leading to system failure, using dynamic supervised learning techniques. RAVEN has now increased in maturity enough for the Beta 1.0 release.

  7. Altitude release mechanism

    DOEpatents

    Kulhanek, Frank C.

    1977-01-01

    An altitude release mechanism for releasing a radiosonde or other measuring instrument from a balloon carrying it up into the atmosphere includes a bottle partially filled with water, a tube sealed into the bottle having one end submerged in the water in the bottle and the free end extending above the top of the bottle and a strip of water-disintegrable paper held within the free end of the tube linking the balloon to the remainder of the package. As the balloon ascends, the lowered atmospheric air pressure causes the air in the bottle to expand, forcing the water in the bottle up the tubing to wet and disintegrate the paper, releasing the package from the balloon.

  8. Controlled-release microchips.

    PubMed

    Sharma, Sadhana; Nijdam, A Jasper; Sinha, Piyush M; Walczak, Robbie J; Liu, Xuewu; Cheng, Mark M-C; Ferrari, Mauro

    2006-05-01

    Efficient drug delivery remains an important challenge in medicine: continuous release of therapeutic agents over extended time periods in accordance with a predetermined temporal profile; local delivery at a constant rate to the tumour microenvironment to overcome much of the systemic toxicity and to improve antitumour efficacy; improved ease of administration, and increasing patient compliance required are some of the unmet needs of the present drug delivery technology. Microfabrication technology has enabled the development of novel controlled-release microchips with capabilities not present in the current treatment modalities. In this review, the current status and future prospects of different types of controlled-release microchips are summarised and analysed with reference to microneedle-based microchips, as well as providing an in-depth focus on microreservoir-based and nanoporous microchips.

  9. Benzene release. status report

    SciTech Connect

    Dworjanyn, L.O.; Rappe, K.G.; Gauglitz, P.A.

    1997-11-04

    Scoping benzene release measurements were conducted on 4 wt percent KTPB `DEMO` formulation slurry using a round, flat bottomed 100-mL flask containing 75 mL slurry. The slurry was agitated with a magnetic stirrer bar to keep the surface refreshed without creating a vortex. Benzene release measurements were made by purging the vapor space at a constant rate and analyzing for benzene by gas chromatography with automatic data acquisition. Some of the data have been rounded or simplified in view of the scoping nature of this study.

  10. Barium release system

    NASA Technical Reports Server (NTRS)

    Lewis, B. W.; Stokes, C. S.; Smith, E. W.; Murphy, W. J. (Inventor)

    1973-01-01

    A chemical system is described for releasing a good yield of free barium neutral atoms and barium ions in the upper atmosphere and interplanetary space for the study of the geophysical properties of the medium. The barium is released in the vapor phase so that it can be ionized by solar radiation and also be excited to emit resonance radiation in the visible range. The ionized luminous cloud of barium becomes a visible indication of magnetic and electrical characteristics in space and allows determination of these properties over relatively large areas at a given time.

  11. A1C

    MedlinePlus

    A1C is a blood test for type 2 diabetes and prediabetes. It measures your average blood glucose, or blood sugar, level over the past 3 ... A1C alone or in combination with other diabetes tests to make a diagnosis. They also use the ...

  12. Data Release Summary Statement

    Atmospheric Science Data Center

    2016-11-14

    ... 3 CALIOP Level 1 data are released with a product maturity classification of Validated Stage1 , indicating that initial validation of ... users for evaluation and to provide feedback to the CALIOP algorithm development team. Users should carefully read the section of the Data ...

  13. Releasable Asbestos Field Sampler

    EPA Science Inventory

    Asbestos aerosolization (or releasability) is the potential for fibrous asbestos structures that are present in a material or on a solid surface to become airborne when the source is disturbed by human activities or natural forces. In turn, the magnitude of the airborne concentra...

  14. Release of OLe peanut

    USDA-ARS?s Scientific Manuscript database

    OLe is a high oleic Spanish-type peanut that has excellent yield and enhanced Sclerotinia blight and pod rot resistance when compared to other high oleic Spanish cultivars. The purpose for releasing OLe is to provide peanut producers with a true Spanish peanut that is high oleic and has enhanced yi...

  15. NASTRAN: April 1982 Release

    NASA Technical Reports Server (NTRS)

    Brugh, R. L.

    1982-01-01

    Latest public release of NASTRAN, April 1982 most efficient and versatile to date. Intended range of applications of NASTRAN includes almost every kind of structure and construction. Users may develop their own analysis capabilities by using Direct Matrix Abstraction Programming (DMAP) language to direct NASTRAN in solution of general matrix problems.

  16. Release the Prisoners Game

    ERIC Educational Resources Information Center

    Van Hecke, Tanja

    2011-01-01

    This article presents the mathematical approach of the optimal strategy to win the "Release the prisoners" game and the integration of this analysis in a math class. Outline lesson plans at three different levels are given, where simulations are suggested as well as theoretical findings about the probability distribution function and its mean…

  17. Hydraulic release oil tool

    SciTech Connect

    Mims, M.G.; Mueller, M.D.; Ehlinger, J.C.

    1992-03-11

    This patent describes a hydraulic release tool. It comprises a setting assembly; a coupling member for coupling to drill string or petroleum production components, the coupling member being a plurality of sockets for receiving the dogs in the extended position and attaching the coupling member the setting assembly; whereby the setting assembly couples to the coupling member by engagement of the dogs in the sockets of releases from and disengages the coupling member in movement of the piston from its setting to its reposition in response to a pressure in the body in exceeding the predetermined pressure; and a relief port from outside the body into its bore and means to prevent communication between the relief port and the bore of the body axially of the piston when the piston is in the setting position and to establish such communication upon movement of the piston from the setting position to the release position and reduce the pressure in the body bore axially of the piston, whereby the reduction of the pressure signals that the tool has released the coupling member.

  18. Releasable Asbestos Field Sampler

    EPA Science Inventory

    Asbestos aerosolization (or releasability) is the potential for fibrous asbestos structures that are present in a material or on a solid surface to become airborne when the source is disturbed by human activities or natural forces. In turn, the magnitude of the airborne concentra...

  19. 28 CFR 2.85 - Conditions of release.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Conditions of release. (a) General conditions of release. (1) The conditions set forth in § 2.204(a)(3)-(6) apply for the reasons set forth in § 2.204(a)(1). These conditions are printed on the certificate of... of § 2.204(c) apply. (d) Application of release conditions to absconder. The provisions of § 2.204(d...

  20. In vitro release study of mono-PEGylated growth hormone-releasing peptide-6 from PLGA microspheres.

    PubMed

    Park, Eun Ji; Na, Dong Hee; Lee, Kang Choon

    2007-10-01

    The purpose of this study was to investigate in vitro release property of mono-PEGylated growth hormone-releasing peptide-6 (GHRP-6) microspheres. The microspheres encapsulating native GHRP-6 or mono-PEG-GHRP-6 were prepared using the single oil-in-water emulsion solvent evaporation method. In vitro release study was performed in 0.1M phosphate buffer, pH 7.4, containing 0.02% Tween 80 and sodium azide at 37 or 55 degrees C. The mono-PEG-GHRP-6 microspheres showed a lower initial burst compared with native GHRP-6 microspheres and zero-order release profile for a 1-month period. The release period was dependent on the PEG size attached to the GHRP-6 with more rapid drug release being observed with the smaller PEG size. This study suggests that PEGylated peptide has good potential as a source for a sustained release microsphere delivery system.

  1. Releasable locking mechanisms

    NASA Technical Reports Server (NTRS)

    Ahmed, Rafiq (Inventor); Wingate, Robert J. (Inventor)

    2005-01-01

    In the aerospace field spacecraft components are held together by separation systems until a specific time when they must be separated or deployed. Customarily a threaded joining bolt engages one of the components to be joined, and a threaded nut is placed on that bolt against the other component so they can be drawn together by a releasable locking assembly. The releasable locking assembly herein includes a plunger having one end coupled to one end of a plunger bolt. The other end is flanged to abut and compress a coil spring when the plunger is advanced toward the interface plane between the two components. When the plunger is so advanced toward the interface plane, the end of the plunger bolt can be connected to the joining bolt. Thus during retraction the joining bolt is drawn to one side of the interface plane by the force of the expanding spring.

  2. Releasable Locking Mechanisms

    NASA Technical Reports Server (NTRS)

    Ahmed, Rafiq (Inventor); Wingate, Robert J. (Inventor)

    2005-01-01

    In the aerospace field spacecraft components are held together by separation systems until a specific time when they must be separated or deployed. Customarily a threaded joining bolt engages one of the components to be joined, and a threaded nut is placed on that bolt against the other component so they can be drawn together by a releasable locking assembly. The releasable locking assembly herein includes a plunger having one end coupled to one end of a plunger bolt. The other end is flanged to abut and compress a coil spring when the plunger is advanced toward the interface plane between the two components. When the plunger is so advanced toward the interface plane, the end of the plunger bolt can be connected to the joining bolt. Thus during retraction the joining bolt is drawn to one side of the interface plane by the force of the expanding spring.

  3. Atmospheric Release Advisory Capability

    SciTech Connect

    Dickerson, M.H.; Gudiksen, P.H.; Sullivan, T.J.

    1983-02-01

    The Atmospheric Release Advisory Capability (ARAC) project is a Department of Energy (DOE) sponsored real-time emergency response service available for use by both federal and state agencies in case of a potential or actual atmospheric release of nuclear material. The project, initiated in 1972, is currently evolving from the research and development phase to full operation. Plans are underway to expand the existing capability to continuous operation by 1984 and to establish a National ARAC Center (NARAC) by 1988. This report describes the ARAC system, its utilization during the past two years, and plans for its expansion during the next five to six years. An integral part of this expansion is due to a very important and crucial effort sponsored by the Defense Nuclear Agency to extend the ARAC service to approximately 45 Department of Defense (DOD) sites throughout the continental US over the next three years.

  4. Sudden releases of gases

    NASA Astrophysics Data System (ADS)

    Chaloupecká, Hana; Jaňour, Zbyněk; Jurčáková, Klára; Kukačka, Libor; Nosek, Štěpán

    2014-03-01

    Conurbations all over the world have enlarged for numberless years. The accidental or intentional releases of gases become more frequent. Therefore, these crises situations have to be studied. The aim of this paper is to describe experiments examining these processes that were carried out in the laboratory of Environmental Aerodynamics of the Institute of Thermomechanics AS CR in Nový Knín. Results show huge puff variability from replica to replica.

  5. Slow-release fertilizer

    NASA Astrophysics Data System (ADS)

    Ming, Douglas W.; Golden, D. C.

    1992-10-01

    A synthetic apatite containing agronutrients and a method for making the apatite are disclosed. The apatite comprises crystalline calcium phosphate having agronutrients dispersed in the crystalline structure. The agronutrients can comprise potassium, magnesium, sulfur, iron, manganese, molybdenum, chlorine, boron, copper and zinc in amounts suited for plant growth. The apatite can optionally comprise a carbonate and/or silicon solubility control agent. The agronutrients are released slowly as the apatite dissolves.

  6. Slow-release fertilizer

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W. (Inventor); Golden, D. C. (Inventor)

    1992-01-01

    A synthetic apatite containing agronutrients and a method for making the apatite are disclosed. The apatite comprises crystalline calcium phosphate having agronutrients dispersed in the crystalline structure. The agronutrients can comprise potassium, magnesium, sulfur, iron, manganese, molybdenum, chlorine, boron, copper and zinc in amounts suited for plant growth. The apatite can optionally comprise a carbonate and/or silicon solubility control agent. The agronutrients are released slowly as the apatite dissolves.

  7. Slow-release fertilizer

    NASA Technical Reports Server (NTRS)

    Ming, Douglas W. (Inventor); Golden, Dadigamuwage C. (Inventor)

    1995-01-01

    A synthetic apatite containing agronutrients and a method for making the apatite are disclosed. The apatite comprises crystalline calcium phosphate having agronutrients dispersed in the crystalline structure. The agronutrients can comprise potassium, magnesium, sulfur, iron, manganese, molybdenum, chlorine, boron, copper and zinc in amounts suited for plant growth. The apatite can optionally comprise a carbonate and/or silicon solubility control agent. The agronutrients are released slowly as the apatite dissolves.

  8. EIA new releases

    SciTech Connect

    Not Available

    1994-12-01

    This report was prepared by the Energy Information Administration. It contains news releases on items of interest to the petroleum, coal, nuclear, electric and alternate fuels industries ranging from economic outlooks to environmental concerns. There is also a listing of reports by industry and an energy education resource listing containing sources for free or low-cost energy-related educational materials for educators and primary and secondary students.

  9. Cryogenic hydrogen release research.

    SciTech Connect

    LaFleur, Angela Christine

    2015-12-01

    The objective of this project was to devolop a plan for modifying the Turbulent Combustion Laboratory (TCL) with the necessary infrastructure to produce a cold (near liquid temperature) hydrogen jet. The necessary infrastructure has been specified and laboratory modifications are currently underway. Once complete, experiments from this platform will be used to develop and validate models that inform codes and standards which specify protection criteria for unintended releases from liquid hydrogen storage, transport, and delivery infrastructure.

  10. Contact: Releasing the news

    NASA Astrophysics Data System (ADS)

    Pinotti, Roberto

    The problem of mass behavior after man's future contacts with other intelligences in the universe is not only a challenge for social scientists and political leaders all over the world, but also a cultural time bomb as well. In fact, since the impact of CETI (Contact with Extraterrestrial Intelligence) on human civilization, with its different cultures, might cause a serious socio-anthropological shock, a common and predetermined worldwide strategy is necessary in releasing the news after the contact, in order to keep possible manifestations of fear, panic and hysteria under control. An analysis of past studies in this field and of parallel historical situations as analogs suggests a definite "authority crisis" in the public as a direct consequence of an unexpected release of the news, involving a devastating "chain reaction" process (from both the psychological and sociological viewpoints) of anomie and maybe the collapse of today's society. The only way to prevent all this is to prepare the world's public opinion concerning contact before releasing the news, and to develop a long-term strategy through the combined efforts of scientists, political leaders, intelligence agencies and the mass media, in order to create the cultural conditions in which a confrontation with ETI won't affect mankind in a traumatic way. Definite roles and tasks in this multi-level model are suggested.

  11. Triggered Release from Polymer Capsules

    SciTech Connect

    Esser-Kahn, Aaron P.; Odom, Susan A.; Sottos, Nancy R.; White, Scott R.; Moore, Jeffrey S.

    2011-07-06

    Stimuli-responsive capsules are of interest in drug delivery, fragrance release, food preservation, and self-healing materials. Many methods are used to trigger the release of encapsulated contents. Here we highlight mechanisms for the controlled release of encapsulated cargo that utilize chemical reactions occurring in solid polymeric shell walls. Triggering mechanisms responsible for covalent bond cleavage that result in the release of capsule contents include chemical, biological, light, thermal, magnetic, and electrical stimuli. We present methods for encapsulation and release, triggering methods, and mechanisms and conclude with our opinions on interesting obstacles for chemically induced activation with relevance for controlled release.

  12. Recommended for release on recognizance: factors affecting pretrial release recommendations.

    PubMed

    Petee, T A

    1994-06-01

    Researchers have acknowledged the influence of pretrial release agencies in judicial decision making regarding bail; however, few researchers have focused on the process used by the pretrial release agencies to make bail-bond recommendations. In this study I sought to establish which factors were most salient in making the decision to recommend a defendant for release on recognizance. I found that both officially sanctioned release criteria and "extralegal" variables were predictive of this decision.

  13. Sustained-release, extended-release, and other time-release formulations in neuropsychiatry.

    PubMed

    Andrade, Chittaranjan

    2015-08-01

    Pills and capsules may release their contents within minutes of ingestion; these are immediate-release formulations. Pills and capsules may also release their contents after a time lag, or a little at a time, or in some other predetermined way; these are time-release formulations. Many drugs in psychiatry have been time-release formulated to reduce their local adverse effects in the gastrointestinal tract, to reduce adverse effects associated with peak blood levels, or to artificially extend their half-life. Time-release formulations are associated with the added advantages of convenience of dosing, improved compliance, and less fluctuation in blood levels across the course of the day. A disadvantage of time-release formulations is that they may be incompletely absorbed; this is a serious issue in patients with acute or chronic intestinal hurry disorders, such as gastroenteritis or irritable bowel syndrome. Time-release formulations may also be more expensive than immediate-release formulations.

  14. Riola release report

    SciTech Connect

    Woodward, E.C.

    1983-08-04

    Eleven hours after execution of the Riola Event (at 0826 PDT on 25 September 1980) in hole U2eq of the Nevada Test Site (NTS), a release of radioactivity began. When the seepage stopped at about noon the following day, up to some 3200 Ci of activity had been dispersed by light variable winds. On 26 September, examination of the geophone records showed six hours of low-level, but fairly continuous, activity before the release. Electrical measurements indicated that most cables were still intact to a depth below the stemming platform. A survey of the ground zero area showed that the seepage came through cracks between the surface conductor and the pad, through cracks in the pad, and through a crack adjacent to the pad around the mousehole (a small hole adjacent to the emplacement hole). To preclude undue radiation exposure or injury from a surprise subsidence, safety measures were instituted. Tritium seepage was suffucient to postpone site activities until a box and pipeline were emplaced to contain and remove the gas. Radiation release modeling and calculations were generally consistent with observations. Plug-hole interaction calculations showed that the alluvium near the bottom of the plug may have been overstressed and that improvements in the design of the plug-medium interface can be made. Experimental studies verified that the surface appearance of the plug core was caused by erosion, but, assuming a normal strength for the plug material, that erosion alone could not account for the disappearance of such a large portion of the stemming platform. Samples from downhole plug experiments show that the plug may have been considerably weaker than had been indicted by quality assurance (QA) samples. 19 references, 32 figures, 10 tables.

  15. Gas releases from salt

    SciTech Connect

    Ehgartner, B.; Neal, J.; Hinkebein, T.

    1998-06-01

    The occurrence of gas in salt mines and caverns has presented some serious problems to facility operators. Salt mines have long experienced sudden, usually unexpected expulsions of gas and salt from a production face, commonly known as outbursts. Outbursts can release over one million cubic feet of methane and fractured salt, and are responsible for the lives of numerous miners and explosions. Equipment, production time, and even entire mines have been lost due to outbursts. An outburst creates a cornucopian shaped hole that can reach heights of several hundred feet. The potential occurrence of outbursts must be factored into mine design and mining methods. In caverns, the occurrence of outbursts and steady infiltration of gas into stored product can effect the quality of the product, particularly over the long-term, and in some cases renders the product unusable as is or difficult to transport. Gas has also been known to collect in the roof traps of caverns resulting in safety and operational concerns. The intent of this paper is to summarize the existing knowledge on gas releases from salt. The compiled information can provide a better understanding of the phenomena and gain insight into the causative mechanisms that, once established, can help mitigate the variety of problems associated with gas releases from salt. Outbursts, as documented in mines, are discussed first. This is followed by a discussion of the relatively slow gas infiltration into stored crude oil, as observed and modeled in the caverns of the US Strategic Petroleum Reserve. A model that predicts outburst pressure kicks in caverns is also discussed.

  16. Hydrogen release behavior.

    SciTech Connect

    LaChance, Jeffrey L.; Dedrick, Daniel E.; Keller, Jay O.; Evans, Gregory Herbert; Houf, William G.; Winters, William Stanley, Jr.; Ruggles, A.; Zhang, J.

    2010-04-01

    The summary of this presentation is: (1) Barrier walls are used to reduce setbacks by factor of 2; (2) We found no ignition-timing vs. over-pressure sensitivities for jet flow obstructed by barrier walls; (3) Cryogenic vapor cloud model indicates hazard length scales exceed the room-temperature release; validation experiments are required to confirm; (4) Light-up maps developed for lean limit ignition; flammability factor model provides good indication of ignition probability; and (5) Auto-ignition is enhanced by blunt-body obstructions - increases gas temperature and promotes fuel/air mixing.

  17. Preparation of delayed release tablet dosage forms by compression coating: effect of coating material on theophylline release.

    PubMed

    El-Malah, Yasser; Nazzal, Sami

    2010-06-01

    In this study, compression-coated tablets were prepared and examined by real-time swelling/erosion analysis and dissolution studies. Of the coating materials, PVP showed no swelling behavior and had no impact on theophylline release. Polyox(®) exhibited swelling behavior of an entangled polymer, which was reflected in its > 14-hour delayed-release profile. Hydroxypropyl methylcellulose (HPMC), which revealed the characteristics of a disentangled polymer, caused a 2-h delay in theophylline release. Based on preliminary texture analysis data, Polyox(®)/PVP blends were used as coating materials to manipulate the onset of drug release from the compression-coated tablets. Of the blends, at a 1:1 ratio, for example, resulted in a burst release after 10 h, which demonstrated the feasibility of preparing delayed release dosage forms by compression coating. Furthermore, it was feasible to predict the dissolution behavior of polymers from their swelling/erosion data, which were generated from texture analysis.

  18. A-1 to Constellation

    NASA Technical Reports Server (NTRS)

    2006-01-01

    The A-1 Test Stand at NASA Stennis Space Center near Bay St. Louis, Miss., was the focus of a ceremony held Thursday to transition the storied facility to a new program of work: testing the J-2X engines that will power the agency's next generation spacecraft, Ares I & V. Standing before the historic structure, with a plaque commemorating the change, are (from left) SSC Center Director Richard Gilbrech; NASA Associate Administrator for Exploration Systems Scott Horowitz; and NASA Space Operations Deputy Associate Administrator for Program Integration Michael Hawes. Ares vehicles are the crew and cargo launch vehicles being developed under NASA's Constellation Program.

  19. A-1 to Constellation

    NASA Image and Video Library

    2006-11-09

    The A-1 Test Stand at NASA Stennis Space Center near Bay St. Louis, Miss., was the focus of a ceremony held Thursday to transition the storied facility to a new program of work: testing the J-2X engines that will power the agency's next generation spacecraft, Ares I & V. Standing before the historic structure, with a plaque commemorating the change, are (from left) SSC Center Director Richard Gilbrech; NASA Associate Administrator for Exploration Systems Scott Horowitz; and NASA Space Operations Deputy Associate Administrator for Program Integration Michael Hawes. Ares vehicles are the crew and cargo launch vehicles being developed under NASA's Constellation Program.

  20. [Compound erythromycin sustained release preparation and its in vitro release].

    PubMed

    Chen, Hai-xia; Chen, Zhi-peng; Wang, Qi-rong; Liu, Ze-kun; Ma, Quan-long

    2011-11-01

    Using the weight-average molecular weight 50 000 polylactic acid (PLA) as a carrier, and a certain proportion of erythromycin (EM) and prednisone acetate (PNA) to mixed prepare the compound erythromycin sustained release preparation (sustained-release tablets). Using ultraviolet spectrophotometry and high performance liquid chromatography (HPLC) to detect separately the release amount of EM and PNA in vitro medium. The sustained-release tablets release for about 21 days, the average content of EM is 99.7 mg/table, RSD = 0.82%; and the average content of PNA is 10.03 mg/table, RSD = 0.93%. Within 21 days, the cumulative releases of EM and PNA are 86.1% and 78.3%, respectively. The drug release is steady and slow after 5 days, the burst release phenomenon in early stage is more significant. The results showed that the sustained-release tablet preparation method is feasible, the release performance is good and the clinical efficacy is significant.

  1. QUICK RELEASABLE DRIVE

    DOEpatents

    Dickson, J.J.

    1958-07-01

    A quick releasable mechanical drive system suitable for use in a nuclear reactor is described. A small reversible motor positions a control rod by means of a worm and gear speed reducer, a magnetic torque clutch, and a bell crank. As the control rod is raised to the operating position, a heavy coil spring is compressed. In the event of an emergency indicated by either a''scram'' signal or a power failure, the current to the magnetic clutch is cut off, thereby freeing the coil spring and the bell crank positioner from the motor and speed reduction gearing. The coil spring will immediately act upon the bell crank to cause the insertion of the control rod. This arrangement will allow the slow, accurate positioning of the control rod during reactor operation, while providing an independent force to rapidly insert the rod in the event of an emergency.

  2. SITELLE's Data Release 1

    NASA Astrophysics Data System (ADS)

    Martin, T. B.; Drissen, L.

    2016-12-01

    Installed at the Canada-France-Hawaii Telescope (CFHT) since August 2015, SITELLE is an Imaging Fourier Transform Spectrometer (IFTS) with an 11×11 field of view. After its prototype SpIOMM, installed at Mont Mégantic (Québec, Canada), it is the second IFTS in the world operating in the visible band (350-1000 nm). It delivers hyperspectral data cubes of 4 million spectra at R˜1500-5000 with a spatial sampling of 0.32" and a filling factor of 100 %. A suite of softwares has been designed to reduce (ORBS) and analyze (ORCS) the data. Based on commissioning data obtained in August 2015, a first stable version has been released in March 2016 which is capable of reducing all the data. In this paper the quality of the calibration is discussed.

  3. Quick release engine cylinder

    DOEpatents

    Sunnarborg, Duane A.

    2000-01-01

    A quick release engine cylinder allows optical access to an essentially unaltered combustion chamber, is suitable for use with actual combustion processes, and is amenable to rapid and repeated disassembly and cleaning. A cylinder member, adapted to constrain a piston to a defined path through the cylinder member, sealingly engages a cylinder head to provide a production-like combustion chamber. A support member mounts with the cylinder member. The support-to-cylinder mounting allows two relationships therebetween. In the first mounting relationship, the support engages the cylinder member and restrains the cylinder against the head. In the second mounting relationship, the cylinder member can pass through the support member, moving away from the head and providing access to the piston-top and head.

  4. Draft Wetlands Rule Released

    NASA Astrophysics Data System (ADS)

    Zielinski, Sarah

    2006-04-01

    The U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers released on 28 March a draft of a new rule to guide compensatory mitigation for when wetlands are unavoidably lost due to development. However, whether the rule is successful in preventing a net loss in wetlands will depend largely on its implementation, according to two wetlands scientists who evaluated the issue for the U.S. National Research Council (NRC) in 2001. Under the federal Clean Water Act, developers who seek to build on wetlands must compensate for any wetlands loss if they are unable to avoid or minimize the loss. Such compensation is covered under the newly proposed compensatory mitigation rule. Benjamin Grumbles, EPA assistant administrator for water, called the rule an ``innovative new standard that will accelerate the pace of wetlands conservation and restoration.''

  5. Optogenetic control of ATP release

    NASA Astrophysics Data System (ADS)

    Lewis, Matthew A.; Joshi, Bipin; Gu, Ling; Feranchak, Andrew; Mohanty, Samarendra K.

    2013-03-01

    Controlled release of ATP can be used for understanding extracellular purinergic signaling. While coarse mechanical forces and hypotonic stimulation have been utilized in the past to initiate ATP release from cells, these methods are neither spatially accurate nor temporally precise. Further, these methods cannot be utilized in a highly effective cell-specific manner. To mitigate the uncertainties regarding cellular-specificity and spatio-temporal release of ATP, we herein demonstrate use of optogenetics for ATP release. ATP release in response to optogenetic stimulation was monitored by Luciferin-Luciferase assay (North American firefly, photinus pyralis) using luminometer as well as mesoscopic bioluminescence imaging. Our result demonstrates repetitive release of ATP subsequent to optogenetic stimulation. It is thus feasible that purinergic signaling can be directly detected via imaging if the stimulus can be confined to single cell or in a spatially-defined group of cells. This study opens up new avenue to interrogate the mechanisms of purinergic signaling.

  6. 19 CFR 142.41 - Line Release.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) ENTRY PROCESS Line Release § 142.41 Line Release. Line Release is an automated system designed to release and tract repetitive shipments. It is a method of entry or immediate delivery extended to...

  7. Controlled Release Applications of Organometals.

    ERIC Educational Resources Information Center

    Thayer, John S.

    1981-01-01

    Reviews two classes of controlled release organometals: (1) distributional, to distribute bioactive materials to control a certain target organism; and (2) protective, to protect surface or interior of some structure from attach by organisms. Specific examples are given including a discussion of controlled release for schistosomiasis. (SK)

  8. Controlled Release Applications of Organometals.

    ERIC Educational Resources Information Center

    Thayer, John S.

    1981-01-01

    Reviews two classes of controlled release organometals: (1) distributional, to distribute bioactive materials to control a certain target organism; and (2) protective, to protect surface or interior of some structure from attach by organisms. Specific examples are given including a discussion of controlled release for schistosomiasis. (SK)

  9. Slow-release fertilizers 101

    Treesearch

    Robin Rose

    2002-01-01

    Slow release fertilizers have been in common use within the horticultural industry for decades. Probably the mostly commonly heard of product is Scott's Osmocote which has been around for a quite a long time. However, some time ago slow release fertilizers moved out of the potted greenhouse environment and onto golf courses, suburban lawns and bushes, and orchards...

  10. Kepler Data Release 4 Notes

    NASA Technical Reports Server (NTRS)

    Van Cleve, Jeffrey (Editor); Jenkins, Jon; Caldwell, Doug; Allen, Christopher L.; Batalha, Natalie; Bryson, Stephen T.; Chandrasekaran, Hema; Clarke, Bruce D.; Cote, Miles T.; Dotson, Jessie L.; Gilliland, Ron; Girouard, Forrest; Haas, Michael R.; Hall, Jennifer; Ibrahim, Khadeejah; Klaus, Todd; Kolodziejczak, Jeff; Li, Jie; McCauliff, Sean D.; Middour, Christopher K.; Pletcher, David L.; Quintana, Elisa V.; Tenenbaum, Peter G.; Twicken, Joe; Uddin, Akm Kamal

    2010-01-01

    The Data Analysis Working Group have released long and short cadence materials, including FFIs and Dropped Targets for the Public. The Kepler Science Office considers Data Release 4 to provide "browse quality" data. These notes have been prepared to give Kepler users of the Multimission Archive at STScl (MAST) a summary of how the data were collected and prepared, and how well the data processing pipeline is functioning on flight data. They will be updated for each release of data to the public archive and placed on MAST along with other Kepler documentation, at http://archive.stsci.edu/kepler/documents.html. Data release 3 is meant to give users the opportunity to examine the data for possibly interesting science and to involve the users in improving the pipeline for future data releases. To perform the latter service, users are encouraged to notice and document artifacts, either in the raw or processed data, and report them to the Science Office.

  11. Nitrogen release during coal combustion

    SciTech Connect

    Baxter, L.L.; Mitchell, R.E.; Fletcher, T.H.; Hurt, R.H.

    1995-02-01

    Experiments in entrained flow reactors at combustion temperatures are performed to resolve the rank dependence of nitrogen release on an elemental basis for a suite of 15 U.S. coals ranging from lignite to low-volatile bituminous. Data were obtained as a function of particle conversion, with overall mass loss up to 99% on a dry, ash-free basis. Nitrogen release rates are presented relative to both carbon loss and overall mass loss. During devolatilization, fractional nitrogen release from low-rank coals is much slower than fractional mass release and noticeably slower than fractional carbon release. As coal rank increases, fractional nitrogen release rate relative to that of carbon and mass increases, with fractional nitrogen release rates exceeding fractional mass and fractional carbon release rates during devolatilization for high-rank (low-volatile bituminous) coals. At the onset of combustion, nitrogen release rates increase significantly. For all coals investigated, cumulative fractional nitrogen loss rates relative to those of mass and carbon passes through a maximum during the earliest stages of oxidation. The mechanism for generating this maximum is postulated to involve nascent thermal rupture of nitrogen-containing compounds and possible preferential oxidation of nitrogen sites. During later stages of oxidation, the cumulative fractional loss of nitrogen approaches that of carbon for all coals. Changes in the relative release rates of nitrogen compared to those of both overall mass and carbon during all stages of combustion are attributed to a combination of the chemical structure of coals, temperature histories during combustion, and char chemistry.

  12. Toxics Release Inventory indicates big increases in releases

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2012-01-01

    Nearly 4 billion pounds of tracked toxic chemicals were released into the environment throughout the United States during 2010, according to an analysis by the U.S. Environmental Protection Agency (EPA) of the Toxics Release Inventory (TRI), the agency announced on 5 January. This is a 16% increase above 2009. The agency said the increase is mainly due to changes in the metal-mining sector, where differences in the chemical composition of ore being mined can result in significant changes in the amount of toxic chemicals. The chemical and primary metals industries were other sectors with increases in toxic releases in 2010, the latest year for which data collection is complete. EPA also noted that although releases in 2010 were higher than during the previous 2 years, they were lower than in 2007 and in prior years.

  13. Mast cell release of superoxide

    SciTech Connect

    Dileepan, K.N.; Simpson, K.M.; Stechschulte, D.J.

    1987-05-01

    The ability of rat serosal mast cells (MC) to release superoxide (O/sub 2//sup -/) upon activation by immunologic and nonimmunologic stimuli was investigated. Purified MC (90-95%) were either sensitized with monoclonal IgE reactive against dinitrophenyl bovine serum albumin (DNP-BSA) and challenged with DNP-BSA, or naive MC were treated with compound 48/80 or ionophore A23187. O/sub 2//sup -/ release was measured by O/sub 2//sup -/ dismutase (SOD)-sensitive reduction of cytochrome C and MC activation was assessed by the release of histamine or (/sup 14/C)5-hydroxytryptamine (5HT). The results reveal that activation of MC by 48/80 or immunologic challenge does not release O/sub 2//sup -/, although these stimuli induce substantial release of histamine and 5HT (40-70%). In contrast, A23187 released O/sub 2//sup -/ (3-6 nMols/10/sup 6/ MC) and histamine (40-80%). In mixed cell preparations containing MC and macrophages (M0), activation of MC with 48/80 resulted in inhibition of M0 O/sub 2//sup -/ release. The MC-mediated inhibition of O/sub 2//sup -/ production was not due to histamine or 5HT, but was due to MC-granule SOD. MC contain abundant quantities of SOD and, therefore, release O/sub 2//sup -/ only when its production exceeds the intracellular SOD threshold following activation with selective stimuli. In addition, the apparent differences in the mode and site of action of various stimuli on MC may contribute to the discriminative release of O/sub 2//sup -/.

  14. Immunophilin regulation of neurotransmitter release.

    PubMed Central

    Steiner, J. P.; Dawson, T. M.; Fotuhi, M.; Snyder, S. H.

    1996-01-01

    BACKGROUND: The immunophilins are proteins that mediate actions of immunosuppressant drugs such as FK506 and cyclosporin A by binding to calcineurin, inhibiting its phosphatase activity, and increasing the phosphorylation level of transcription factors required for interleukin 2 formation. Though concentrations in the brain greatly exceed levels in immune tissues, no function has been previously established for nervous system immunophilins. Nitric oxide (NO) has been implicated in neurotransmitter release. FK506 appears to inhibit NO production by maintaining NO synthase in a highly phosphorylated and thereby inactivated state. Accordingly, we examined effects of FK506 and cyclosporin A on neurotransmitter release in PC12 cells treated with nerve growth factor (NGF) and in rat brain striatal synaptosomes. MATERIALS AND METHODS: We monitored effects of immunophilin ligands on [3H]-neurotransmitter release from PC12 cells differentiated with NGF. Rat brain striatal synaptosomes were loaded with radiolabeled transmitters and treated with FK506 or cyclosporin A prior to initiating neurotransmitter release with N-methyl-D-aspartate (NMDA) or potassium depolarization. Striatal synaptosomes were also loaded with 32P-orthophosphate and treated with FK506. 32P-labeled synaptic vesicle proteins were isolated from these synaptosomes in an attempt to relate specific FK506-dependent phosphorylation of vesicle proteins with the effects of FK506 on neurotransmitter release. Identification of proteins targetted by FK506 was made by immunoblot analysis and immunoprecipitation. RESULTS: Low nanomolar concentrations of the immunosuppressant drugs FK506 and cyclosporin A (CsA) inhibit transmitter release from PC-12 cells and from NMDA-stimulated brain synaptosomes. By contrast, the immunosuppressants augment depolarization-induced transmitter release from synaptosomes. Synapsin I, a synaptic vesicle phosphoprotein, displays enhanced phosphorylation in the presence of FK506

  15. Controlled release liquid dosage formulation

    DOEpatents

    Benton, Ben F.; Gardner, David L.

    1989-01-01

    A liquid dual coated dosage formulation sustained release pharmaceutic having substantial shelf life prior to ingestion is disclosed. A dual coating is applied over controlled release cores to form dosage forms and the coatings comprise fats melting at less than approximately 101.degree. F. overcoated with cellulose acetate phthalate or zein. The dual coated dosage forms are dispersed in a sugar based acidic liquid carrier such as high fructose corn syrup and display a shelf life of up to approximately at least 45 days while still retaining their release profiles following ingestion. Cellulose acetate phthalate coated dosage form cores can in addition be dispersed in aqueous liquids of pH <5.

  16. Commercial SNF Accident Release Fractions

    SciTech Connect

    J. Schulz

    2004-11-05

    The purpose of this analysis is to specify and document the total and respirable fractions for radioactive materials that could be potentially released from an accident at the repository involving commercial spent nuclear fuel (SNF) in a dry environment. The total and respirable release fractions are used to support the preclosure licensing basis for the repository. The total release fraction is defined as the fraction of total commercial SNF assembly inventory, typically expressed as an activity inventory (e.g., curies), of a given radionuclide that is released to the environment from a waste form. Radionuclides are released from the inside of breached fuel rods (or pins) and from the detachment of radioactive material (crud) from the outside surfaces of fuel rods and other components of fuel assemblies. The total release fraction accounts for several mechanisms that tend to retain, retard, or diminish the amount of radionuclides that are available for transport to dose receptors or otherwise can be shown to reduce exposure of receptors to radiological releases. The total release fraction includes a fraction of airborne material that is respirable and could result in inhalation doses; this subset of the total release fraction is referred to as the respirable release fraction. Accidents may involve waste forms characterized as: (1) bare unconfined intact fuel assemblies, (2) confined intact fuel assemblies, or (3) canistered failed commercial SNF. Confined intact commercial SNF assemblies at the repository are contained in shipping casks, canisters, or waste packages. Four categories of failed commercial SNF are identified: (1) mechanically and cladding-penetration damaged commercial SNF, (2) consolidated/reconstituted assemblies, (3) fuel rods, pieces, and debris, and (4) nonfuel components. It is assumed that failed commercial SNF is placed into waste packages with a mesh screen at each end (CRWMS M&O 1999). In contrast to bare unconfined fuel assemblies, the

  17. EPA Releases EJ 2020 Agenda

    EPA Pesticide Factsheets

    EPA released the EJ 2020 Action Agenda, the Agency’s environmental justice strategic plan for 2016 to 2020. EJ 2020 will further integrate environmental justice considerations in all of the Agency’s programs.

  18. SELF-RELEASING GRAPPLING DEVICE

    DOEpatents

    Hoover, D.A. Sr.

    1963-11-01

    >A self-releasing grappling device that lifts by virtue of engagement between clamping jaws and the undercut lower side of a conical head of a lifting lug attached to the object to be lifted and employs a releasing sleeve on the lug to free the jaws from the lug is presented. When the jaws are to be released, they are dropped over the releasing sleeve, which is located well below lug head. When the jaws are lifted, they engage a conical surface on the sleeve and lift it up to the head of the lifting lug. In this position of the sleeve, the lower side of the lug head is covered by the sleeve and so cannot be engaged by the jaws, which move past before clearing the sleeve. (AEC)

  19. Tyrosine - Effects on catecholamine release

    NASA Technical Reports Server (NTRS)

    Acworth, Ian N.; During, Matthew J.; Wurtman, Richard J.

    1988-01-01

    Tyrosine administration elevates striatal levels of dopamine metabolites in animals given treatments that accelerate nigrostriatal firing, but not in untreated rats. We examined the possibility that the amino acid might actually enhance dopamine release in untreated animals, but that the technique of measuring striatal dopamine metabolism was too insensitive to demonstrate such an effect. Dopamine release was assessed directly, using brain microdialysis of striatal extracellular fluid. Tyrosine administration (50-200 mg/kg IP) did indeed cause a dose related increase in extracellular fluid dopamine levels with minor elevations in levels of DOPAC and HVA, its major metabolites, which were not dose-related. The rise in dopamine was short-lived, suggesting that receptor-mediated feedback mechanisms responded to the increased dopamine release by diminishing neuronal firing or sensitivity to tyrosine. These observations indicate that measurement of changes in striatal DOPAC and HVA, if negative, need not rule out increases in nigrostriatal dopamine release.

  20. Best practices for code release

    NASA Astrophysics Data System (ADS)

    Berriman, G. Bruce

    2016-01-01

    In this talk, I want to describe what I think are the best practices for releasing code and having it adopted by end users. Make sure your code is licensed, so users will know how the software can be used and modified, and place your code in a public repository that (and make sure that you follow institutional policies in doing this). Yet licensing and releasing code are not enough: the code must be organized and documented so users can understand what it does, what its limitations are, and how to build and use it. I will describe what I think are best practices in developing the content to support release, including tutorials, design documents, specifications of interfaces and so on. Much of what I have learned on based on ten years of experience in supporting releases of the Montage Image Mosaic Engine.

  1. Birth control - slow release methods

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007555.htm Birth control - slow release methods To use the sharing features on this page, please enable JavaScript. Certain birth control methods contain man-made forms of hormones. These ...

  2. Salt release from potato crisps.

    PubMed

    Tian, Xing; Fisk, Ian D

    2012-04-01

    The rate of salt release in-mouth from salted potato crisps was evaluated. It was hypothesised that a slow steady release of sodium would occur on chewing and hydration; to test this a crisp was chewed and held in the oral cavity without swallowing for 60 s. Sodium release was measured over the entire holding period, after 20-30 s a peak in salivary sodium levels was recorded. A similar trend was observed with sensory perceived saltiness by trained panellists. The results suggest that a significant proportion of the crisp's salt flavouring is released in a pulse-type mechanism which would not be encountered when the crisp is exposed to normal eating patterns and would result in the consumption of a large proportion of unperceived sodium.

  3. Oxidative calcium release from catechol.

    PubMed

    Riley, Patrick A; Stratford, Michael R L

    2015-04-01

    Oxidation of 4-methylcatechol previously exposed to aqueous calcium chloride was shown by ion chromatography to be associated with release of calcium ions. The catechol was oxidised to the corresponding orthoquinone by the use of tyrosinase from Agaricus bisporus. The oxidative release of calcium from the catechol is ascribed to the diminution of the available hydroxyl functions able to act as chelating groups. Our results suggest that the redox status of melanin may regulate calcium binding and influence calcium levels in pigmented cells.

  4. Energy release in solar flares

    NASA Technical Reports Server (NTRS)

    Brown, John C.; Correia, Emilia; Farnik, Frantisek; Garcia, Howard; Henoux, Jean-Claude; La Rosa, Ted N.; Machado, Marcos E. (Compiler); Nakajima, Hiroshi; Priest, Eric R.

    1994-01-01

    Team 2 of the Ottawa Flares 22 Workshop dealt with observational and theoretical aspects of the characteristics and processes of energy release in flares. Main results summarized in this article stress the global character of the flaring phenomenon in active regions, the importance of discontinuities in magnetic connectivity, the role of field-aligned currents in free energy storage, and the fragmentation of energy release in time and space.

  5. Ion release from orthodontic appliances.

    PubMed

    Staffolani, N; Damiani, F; Lilli, C; Guerra, M; Staffolani, N J; Belcastro, S; Locci, P

    1999-08-01

    The microbiological and enzymatic characteristics of the oral cavity would seem to provide a suitable environment for the corrosion of metals. We assayed the release of metal ions from one orthodontic appliance which included two 304 and 316 steel molar bands, ten 316 steel brackets, one nickel-titanium archwire and a brazing alloy to connect the elements of molar bands and brackets. The orthodontic appliance was dipped in both inorganic (pH 3.5-6.5) and organic acid solutions (w/v 1% each of tartaric, citric and ascorbic acid at pH 2.2 or 1.5% each of lactic and acetic acid at pH 2.5). The release of nickel (Ni), chromium (Cr), copper (Cu), silver (Ag) and palladium (Pd) was determined using an atomic absorption spectrophotometer Varian AA 10. The release of Ni, Cr and Cu was markedly less at pH 6.5 than at pH 3.5 at all time points in acid solution. Daily release/single appliance after the first day decreased. Contrary to expectations, appliances immersed in organic acid solutions at pH 2.2 or 2.5 after 28 days generally released an amount of ions similar to that observed in inorganic acid solution at pH 3.5, with the exception of Cu. Release of silver and palladium, two metals present in the brazing alloy, proved to be very low (approximately 0.2 microgram after 28 days). The daily release of Ni, Cu and Cr by an orthodontic appliance in acid pH, particularly favourable to corrosion, was well below that ingested with a normal daily diet. It is therefore concluded that the quantities of metal ions released in our experimental conditions should not be cause for concern in utilising the appliance.

  6. Energy release in solar flares

    NASA Technical Reports Server (NTRS)

    Brown, John C.; Correia, Emilia; Farnik, Frantisek; Garcia, Howard; Henoux, Jean-Claude; La Rosa, Ted N.; Machado, Marcos E. (Compiler); Nakajima, Hiroshi; Priest, Eric R.

    1994-01-01

    Team 2 of the Ottawa Flares 22 Workshop dealt with observational and theoretical aspects of the characteristics and processes of energy release in flares. Main results summarized in this article stress the global character of the flaring phenomenon in active regions, the importance of discontinuities in magnetic connectivity, the role of field-aligned currents in free energy storage, and the fragmentation of energy release in time and space.

  7. Added release time in diffusion/dissolution coupled release.

    PubMed

    Nuxoll, Eric

    2015-10-15

    While increasingly sophisticated models have been developed to more accurately predict dispersed solute release from complex systems, distillation of their results into quantitative trends has been difficult. Here, the numerically calculated release profiles of coupled diffusion/dissolution systems are quantified by their cumulative release time (CRT) and compared against corresponding diffusion-controlled limits. The increase in CRT due to a finite dissolution rate was found to vary inversely with the second Damköhler number across several orders of magnitude, and also vary linearly with the amount of solid drug loaded in the system. The analytical nature of the relationship provides new physical insights into the system and appears to be indifferent to the form of the secondary rate-limiting step. This work provides a simple analytical expression with which one can not only predict the mean release time for a given set of parameter values, but understand precisely how each parameter value will affect it. The simplicity of the correlation and the lack of apparent limits to its validity also suggest the existence of an analytical pathway for its derivation, which may yield additional insights into the effect of secondary rate processes on controlled release.

  8. Overview of extended release tacrolimus in solid organ transplantation

    PubMed Central

    Patel, Neha; Cook, Abigail; Greenhalgh, Elizabeth; Rech, Megan A; Rusinak, Joshua; Heinrich, Lynley

    2016-01-01

    Tacrolimus (Prograf©, Astellas Pharma Europe Ltd, Staines, United Kingdom; referred to as tacrolimus-BID) is an immunosuppressive agent to prevent and treat allograft rejection in kidney transplant recipients in combination with mycophenolate mofetil, corticosteroids, with or without basiliximab induction. The drug has also been studied in liver, heart and lung transplant; however, these are currently off-label indications. An extended release tacrolimus formulation (Advagraf©, Astagraf XL©) allows for once-daily dosing, with the potential to improve adherence. Extended release tacrolimus has similar absorption, distribution, metabolism and excretion to tacrolimus-BID. Phase I pharmacokinetic trials comparing extended release tacrolimus and tacrolimus-BID have demonstrated a decreased maximum concentration (Cmax) and delayed time to maximum concentration (tmax) with the extended release formulation; however, AUC0-24 was comparable between formulations. Overall extended release tacrolimus has a very similar safety and efficacy profile to tacrolimus-BID. It is not recommended in the use of liver transplant patient’s due to the increased risk of mortality in female recipients. There has been minimal data regarding the use of extended release tacrolimus in heart and lung transplant recipients. With the current data available for all organ groups the extended release tacrolimus should be dosed in a 1:1 fashion, the exception may be the cystic fibrosis population where their initial dose may need to be higher. PMID:27011912

  9. Cholecystokinin facilitates glutamate release by increasing the number of readily releasable vesicles and releasing probability.

    PubMed

    Deng, Pan-Yue; Xiao, Zhaoyang; Jha, Archana; Ramonet, David; Matsui, Toshimitsu; Leitges, Michael; Shin, Hee-Sup; Porter, James E; Geiger, Jonathan D; Lei, Saobo

    2010-04-14

    Cholecystokinin (CCK), a neuropeptide originally discovered in the gastrointestinal tract, is abundantly distributed in the mammalian brains including the hippocampus. Whereas CCK has been shown to increase glutamate concentration in the perfusate of hippocampal slices and in purified rat hippocampal synaptosomes, the cellular and molecular mechanisms whereby CCK modulates glutamatergic function remain unexplored. Here, we examined the effects of CCK on glutamatergic transmission in the hippocampus using whole-cell recordings from hippocampal slices. Application of CCK increased AMPA receptor-mediated EPSCs at perforant path-dentate gyrus granule cell, CA3-CA3 and Schaffer collateral-CA1 synapses without effects at mossy fiber-CA3 synapses. CCK-induced increases in AMPA EPSCs were mediated by CCK-2 receptors and were not modulated developmentally and transcriptionally. CCK reduced the coefficient of variation and paired-pulse ratio of AMPA EPSCs suggesting that CCK facilitates presynaptic glutamate release. CCK increased the release probability and the number of readily releasable vesicles with no effects on the rate of recovery from vesicle depletion. CCK-mediated increases in glutamate release required the functions of phospholipase C, intracellular Ca(2+) release and protein kinase Cgamma. CCK released endogenously from hippocampal interneurons facilitated glutamatergic transmission. Our results provide a cellular and molecular mechanism to explain the roles of CCK in the brain.

  10. Effect of in vitro inorganic lead on dopamine release from superfused rat striatal synaptosomes.

    PubMed

    Minnema, D J; Greenland, R D; Michaelson, I A

    1986-06-30

    The effect of inorganic lead in vitro in several aspects of [3H]dopamine release from superfused rat striatal synaptosomes was examined. Under conditions of spontaneous release, lead (1-30 microM) induced dopamine release in a concentration-dependent manner. The onset of the lead-induced release was delayed by approximately 15-30 sec. The magnitude of dopamine release induced by lead was increased when calcium was removed from the superfusing buffer. Lead-induced release was unaffected in the presence of putative calcium, sodium, and/or potassium channel blockers (nickel, tetrodotoxin, tetraethylammonium, respectively). Depolarization-evoked dopamine release, produced by a 1-sec exposure to 61 mM potassium, was diminished at calcium concentrations below 0.254 mM. The onset of depolarization-evoked release was essentially immediate following exposure of the synaptosomes to high potassium. The combination of lead (3 or 10 microM) with high potassium reduced the magnitude of depolarization-evoked dopamine release. This depression of depolarization-evoked release by lead was greater in the presence of 0.25 mM than 2.54 mM calcium in the superfusing buffer. These findings demonstrate multiple actions of lead on synaptosomal dopamine release. Lead can induce dopamine release by yet unidentified neuronal mechanisms independent of external calcium. Lead can also reduce depolarization-evoked dopamine release by apparent competition with calcium influx at the neuronal membrane calcium channel.

  11. Effect of in vitro inorganic lead on dopamine release from superfused rat striatal synaptosomes

    SciTech Connect

    Minnema, D.J.; Greenland, R.D.; Michaelson, I.A.

    1986-06-30

    The effect of inorganic lead in vitro in several aspects of (/sup 3/H)dopamine release from superfused rat striatal synaptosomes was examined. Under conditions of spontaneous release, lead (1-30 microM) induced dopamine release in a concentration-dependent manner. The onset of the lead-induced release was delayed by approximately 15-30 sec. The magnitude of dopamine release induced by lead was increased when calcium was removed from the superfusing buffer. Lead-induced release was unaffected in the presence of putative calcium, sodium, and/or potassium channel blockers (nickel, tetrodotoxin, tetraethylammonium, respectively). Depolarization-evoked dopamine release, produced by a 1-sec exposure to 61 mM potassium, was diminished at calcium concentrations below 0.254 mM. The onset of depolarization-evoked release was essentially immediate following exposure of the synaptosomes to high potassium. The combination of lead (3 or 10 microM) with high potassium reduced the magnitude of depolarization-evoked dopamine release. This depression of depolarization-evoked release by lead was greater in the presence of 0.25 mM than 2.54 mM calcium in the superfusing buffer. These findings demonstrate multiple actions of lead on synaptosomal dopamine release. Lead can induce dopamine release by yet unidentified neuronal mechanisms independent of external calcium. Lead can also reduce depolarization-evoked dopamine release by apparent competition with calcium influx at the neuronal membrane calcium channel.

  12. Dopaminergic regulation of enkephalin release.

    PubMed

    Llorens-Cortes, C; Zini, S; Gros, C; Schwartz, J C

    1991-04-01

    The effects of dopamine receptor stimulation on enkephalin release were evaluated in vitro and in vivo by measuring the changes in the levels of [Met5]enkephalin (YGGFM) and Tyr-Gly-Gly (YGG), a characteristic extracellular enkephalin metabolite produced under the action of enkephalinase. In rat striatal slices, D1-receptor agonists or antagonists did not modify enkephalin release. By contrast, D2-receptor agonists enhanced the potassium-induced release of YGGFM and YGG without affecting spontaneous release from nondepolarized slices. This response was prevented by the D2-receptor antagonists haloperidol and RIV 2093, the latter compound being more potent, which suggested the involvement of a putative D2-receptor subtype. Acute administration of apomorphine or selective D2-receptor agonists, but not that of a D1-receptor agonist, enhanced the steady-state level of YGG without affecting the YGGFM level in rat striatum. The effect was blocked selectively by D2-receptor antagonists which, administered alone, had no effect. These observations indicate that D2-receptor stimulation in vitro or in vivo facilitates enkephalin release from striatal neurons, but that endogenous dopamine does not exert any tonic influence upon the opioid peptide neuron activity under basal conditions. However, chronic administration of haloperidol resulted in increases in striatal YGGFM and YGG, an effect presumably reflecting a long-term adaptive process.

  13. Controlled release from recombinant polymers.

    PubMed

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-09-28

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed.

  14. Controlled Release from Recombinant Polymers

    PubMed Central

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-01-01

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed. PMID:24956486

  15. Nanostructured Diclofenac Sodium Releasing Material

    NASA Astrophysics Data System (ADS)

    Nikkola, L.; Vapalahti, K.; Harlin, A.; Seppälä, J.; Ashammakhi, N.

    2008-02-01

    Various techniques have been developed to produce second generation biomaterials for tissue repair. These include extrusion, molding, salt leaching, spinning etc, but success in regenerating tissues has been limited. It is important to develop porous material, yet with a fibrous structure for it to be biomimetic. To mimic biological tissues, the extra-cellular matrix usually contains fibers in nano scale. To produce nanostructures, self-assembly or electrospinning can be used. Adding a drug release function to such a material may advance applications further for use in controlled tissue repair. This turns the resulting device into a multifunctional porous, fibrous structure to support cells and drug releasing properties in order to control tissue reactions. A bioabsorbable poly(ɛ-caprolactone-co-D,L lactide) 95/5 (PCL) was made into diluted solution using a solvent, to which was added 2w-% of diclofenac sodium (DS). Nano-fibers were made by electrospinning onto substrate. Microstructure of the resulting nanomat was studied using SEM and drug release profiles with UV/VIS spectroscopy. Thickness of the electrospun nanomat was about 2 mm. SEM analysis showed that polymeric nano-fibers containing drug particles form a highly interconnected porous nano structure. Average diameter of the nano-fibers was 130 nm. There was a high burst peak in drug release, which decreased to low levels after one day. The used polymer has slow a degradation rate and though the nanomat was highly porous with a large surface area, drug release rate is slow. It is feasible to develop a nano-fibrous porous structure of bioabsorbable polymer, which is loaded with test drug. Drug release is targeted at improving the properties of biomaterial for use in controlled tissue repair and regeneration.

  16. 38 CFR 36.4327 - Release of security.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Release of security. 36... security. (a)(1) Except upon full payment of the indebtedness, or except as provided in paragraph (a)(2) of... right in or to real property held as security for a guaranteed or insured loan, or grant a fee or...

  17. Counterion release and electrostatic adsorption

    PubMed

    Sens; Joanny

    2000-05-22

    The effective charge of a rigid polyelectrolyte (PE) approaching an oppositely charged surface is studied. The cases of a weak (annealed) and strongly charged PE with condensed counterions (such as DNA) are discussed. In the most interesting case of the adsorption onto a substrate of low dielectric constant (such as a lipid membrane or a mica sheet) the condensed counterions are not always released as the PE approaches the substrate, because of the major importance of the image-charge effect. For the adsorption onto a surface with freely moving charges, the image-charge effect becomes less important and full release is often expected.

  18. Hydrocarbon release investigations in Missouri

    SciTech Connect

    Fels, J.B.

    1996-09-01

    Hydrocarbon releases are among the most common environmental problems in Missouri, as well as across the country. Old, unprotected underground storage tanks and buried piping from the tanks to pumps are notorious sources of petroleum contamination at LUST (leaking underground storage tank) sites. Missouri has an estimated 5000 LUST sites across the state with the majority being simple spills into clay-rich soils or into a shallow perched water system. However, in the southern half of the state, where residual soils and karst bedrock are not conducive to trapping such releases, significant groundwater supplies are at risk. This article discusses the process used to identify the source of contamination.

  19. Index to NASA News Releases 1995

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This issue of the index to NASA News Releases contains a listing of news releases distributed by the Office of Public Affairs, NASA Headquarters, during 1995. The index is arranged in six sections: Subject index, Personal name index, News release number index, Accession number index, Speeches, and News releases.

  20. 28 CFR 2.83 - Release planning.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Release planning. 2.83 Section 2.83... Release planning. (a) All grants of parole shall be conditioned on the development of a suitable release... parole date for purposes of release planning for up to 120 days without a hearing. If efforts...

  1. 7 CFR 550.29 - Press releases.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Press releases. 550.29 Section 550.29 Agriculture... Program Management § 550.29 Press releases. Press releases or other forms of public notification will be... opportunity to review, in advance, all written press releases and any other written information to be...

  2. Very low shock release pyromechanisms

    NASA Astrophysics Data System (ADS)

    Soulier, Grégory; Gaechter, J. Pierre

    2003-09-01

    Pyromechanisms have long been used in space for launchers and satellites applications, particularly for release or separation purposes, such as bolt cutters, release nuts, pyrovalves, etc. They offer a great variety of uses, a high potential between the power supplied and the weight on board with, at the same time, a high reliability. However, they also feature a drawback due to the high dynamics generated by their functioning. Pyroshocks levels may damage adjacent sensible equipments (eg electronic boxes, reaction wheels,...) and require to design damping systems or to remove those equipments from the shock source. In a mechanism using standard pyrodevices, shock generation comes from three sources: 1. Pyrotechnic reaction. 2. Energy from internal parts in motion. 3. The release of structural constraints. Devices developed by E. LACROIX have the objectives to avoid the two last ones by: Using heat and gas generated by pyrotechnic effects. Reducing speed of parts in motion. Reducing release speed of mechanical constraints. In this paper, LACROIX presents two products named "PYROSOFT" and "VIROSOFT " designed by LACROIX and supported by CNES Toulouse (French Space Agency). R&T contracts.

  3. Spatial release from informational masking

    NASA Astrophysics Data System (ADS)

    Rakerd, Brad; Aaronson, Neil L.

    2001-05-01

    A new method for investigating spatial release from informational masking was developed and employed in two experiments. The new method is computer controlled and efficient. It employs the versatile coordinate response measure speech stimulus set [Bolia et al., J. Acoust. Soc. Am. 107, 1065 (2000)]. The experiments were conducted in an anechoic room, with a primary loudspeaker in front of the listener and a secondary loudspeaker at 60 deg to the right. Target messages were presented from the primary speaker only. For a standard, distractor messages, simultaneous with the target, were also presented from the primary speaker only. Spatial release was measured by presenting the distractors from both primary and secondary speakers with a temporal offset. Experiment 1 fixed the offset (secondary leading, +4 ms) and varied the number of distractors (1 to 3) and the target-to-distractor ratio (-12 to +4 dB). Masking release, sometimes as large as 10 dB, was found for all combinations of these variables. Experiment 2 varied the offset over a wide range of values. Substantial release from masking was found for both positive and negative offsets, but only in the range in which speech echoes are suppressed (<50 ms). [Work supported by NIDCD grant DC 00181.

  4. 2014 Pee Dee germplasm releases

    USDA-ARS?s Scientific Manuscript database

    PD 05035, PD 05041, PD 05064, PD 05069, PD 05070, PD 05071, PD 06001, and PD 06078 are noncommercial breeding lines of cotton jointly released by the Agricultural Research Service, United States Department of Agriculture, Clemson University Experiment Station, and Cotton Incorporated in 2014. These ...

  5. Modelling and simulations of controlled release fertilizer

    NASA Astrophysics Data System (ADS)

    Irfan, Sayed Ameenuddin; Razali, Radzuan; Shaari, Ku Zilati Ku; Mansor, Nurlidia

    2016-11-01

    The recent advancement in controlled release fertilizer has provided an alternative solution to the conventional urea, controlled release fertilizer has a good plant nutrient uptake they are environment friendly. To have an optimum plant intake of nutrients from controlled release fertilizer it is very essential to understand the release characteristics. A mathematical model is developed to predict the release characteristics from polymer coated granule. Numerical simulations are performed by varying the parameters radius of granule, soil water content and soil porosity to study their effect on fertilizer release. Understanding these parameters helps in the better design and improve the efficiency of controlled release fertilizer.

  6. Kepler Data Release 3 Notes

    NASA Technical Reports Server (NTRS)

    Cleve, Jeffrey E.

    2010-01-01

    This describes the collection of data and the processing done on it so when researchers around the world get the Kepler data sets (which are a set of pixels from the telescope of a particular target (star, galaxy or whatever) over a 3 month period) they can adjust their algorithms fro things that were done (like subtracting all of one particular wavelength for example). This is used to calibrate their own algorithms so that they know what it is they are starting with. It is posted so that whoever is accessing the publicly available data (not all of it is made public) can understand it .. (most of the Kepler data is under restriction for 1 - 4 years and is not available, but the handbook is for everyone (public and restricted) The Data Analysis Working Group have released long and short cadence materials, including FFls and Dropped Targets for the Public. The Kepler Science Office considers Data Release 3 to provide "browse quality" data. These notes have been prepared to give Kepler users of the Multimission Archive at STScl (MAST) a summary of how the data were collected and prepared, and how well the data processing pipeline is functioning on flight data. They will be updated for each release of data to the public archive and placed on MAST along with other Kepler documentation, at http:// archive.stsci.edu/kepler/documents.html .Data release 3 is meant to give users the opportunity to examine the data for possibly interesting science and to involve the users in improving the pipeline for future data releases. To perform the latter service, users are encouraged to notice and document artifacts, either in the raw or processed data, and report them to the Science Office.

  7. Impact of plasma protein binding on cargo release by thermosensitive liposomes probed by fluorescence correlation spectroscopy.

    PubMed

    Mittag, Judith J; Kneidl, Barbara; Preiβ, Tobias; Hossann, Martin; Winter, Gerhard; Wuttke, Stefan; Engelke, Hanna; Rädler, Joachim O

    2017-10-01

    Thermosensitive liposomes (TSLs) whose phase-transition temperature (Tm) lies slightly above body temperature are ideal candidates for controlled drug release via local hyperthermia. Recent studies, however, have revealed disruptive shifts in the release temperature Tr in mouse plasma, which are attributed to undefined interactions with blood proteins. Here, we study the effects of four major plasma proteins - serum albumin (SA), transferrin (Tf), apolipoprotein A1 (ApoA1) and fibrinogen (Fib) - on the temperature-dependent release of fluorescein di-β-D-galactopyranoside (FDG) from TSLs. The amount of fluorescein released was quantified by fluorescence correlation spectroscopy (FCS) after hydrolysis of FDG with β-galactosidase (β-Gal). This approach is more sensitive and thus superior to previous release assays, as it is impervious to the confounding effects of Triton on conventional fluorescence measurements. The assay determines the molar release ratio, i.e. the number of molecules released per liposome. We show that shifts in the Tr of release do not reflect protein affinities for the liposomes derived from adsorption isotherms. We confirm a remarkable shift in induced release towards lower temperatures in the presence of mouse plasma. In contrast, exposure to rat or human plasma, or fetal bovine serum (FBS), has no effect on the release profile. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Nickel release from stainless steels.

    PubMed

    Haudrechy, P; Mantout, B; Frappaz, A; Rousseau, D; Chabeau, G; Faure, M; Claudy, A

    1997-09-01

    In 1994, a study of nickel release and allergic contact dermatitis from nickel-plated metals and stainless steels was published in this journal. It was shown that low-sulfur stainless steel grades like AISI 304, 316L or 430 (S < or = 0.007%) release less than 0.03 microgram/cm2/week of nickel in acid artificial sweat and elicit no reactions in patients already sensitized to nickel. In contrast, nickel-plated samples release around 100 micrograms/cm2/week of Ni and high-sulfur stainless steel (AISI 303-S approximately 0.3%) releases about 1.5 micrograms/cm2/week in this acid artificial sweat. Applied on patients sensitized to nickel, these metals elicit positive reactions in 96% and 14%, respectively, of the patients. The main conclusion was that low-sulfur stainless steels like AISI 304, 316L or 430, even when containing Ni, should not elicit nickel contact dermatitis, while metals having a mean corrosion resistance like a high-sulfur stainless steel (AISI 303) or nickel-plated steel should be avoided. The determining characteristic was in fact the corrosion resistance in chloride media, which, for stainless steels, is connected, among other factors, to the sulfur content. Thus, a question remained concerning the grades with an intermediate sulfur content, around 0.03%, which were not studied. They are the object of the study presented in this paper. 3 tests were performed: leaching experiments, dimethylglyoxime and HNO3 spot tests, and clinical patch tests; however, only stainless steels were tested: a low-sulfur AISI 304 and AISI 303 as references and 3 grades with a sulfur content around 0.03%: AISI 304L, AISI 304L added with Ca, AISI 304L+Cu. Leaching experiments showed that the 4 non-resulfurised grades released less than 0.5 microgram/cm2/week in acid sweat while the reulfurized AISI 303 released around or more than 0.5 microgram/cm2/week. This is explained by the poorer corrosion resistance of the resulfurized grade. Yet all these grades had the same

  9. [Preparation and in vitro release characteristics of pulsed-release tablets of Apocynum venetum].

    PubMed

    Yang, Huasheng; Xie, Fugui; Yang, Yuewen; Luo, Yongming

    2011-06-01

    Using Apocynum venetum as a model drug to prepare pulsed-release tablets based on diffusion, swelling, osmotic pressure mechanism and to evaluate the release characteristics. The pulsatile release tablets were prepared by film coating methods using HPMC E5 and Eudragit The effect of formulation on pulsatile release of A. venetum was investigated. The pulsed-release tablet was prepared by a swelling layer coating which contains HPMC E5 and a controlled-release membrane containning Eudragit. The delayed release time of the tablets was (5.0 +/- 0.5) h. The pulsatile release characteristics of A. venetum pulsatile release tablets were confirmed in vitro.

  10. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  11. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  12. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a loan...

  13. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a loan...

  14. Public Release of Pan-STARRS Data

    NASA Astrophysics Data System (ADS)

    Flewelling, Heather; Consortium, panstarrs

    2015-08-01

    Pan-STARRS 1 is a 1.8 meter survey telescope, located on Haleakala, Hawaii, with a 1.4 Gigapixel camera, a 7 square degree field of view, and 5 filters (g,r,i,z,y). The public release of data, which is available to everyone, consists of 4 years of data taken between May 2010 and April 2014. Two of the surveys available in the public release are the 3pi survey and the Medium Deep (MD) survey. The 3pi survey has roughly 60 epochs (12 per filter) covering 3/4 of the sky and everything north of -30 degrees declination. The MD survey consists of 10 fields, observed in a couple of filters each night, usually 8 exposures per filter per field, for about 4000 epochs per MD field. The available data product are accessed through the “Postage Stamp Server” and through the Published Science Products Subsystem (PSPS), both of these are available through the Pan-STARRS Science Interface (PSI). The Postage Stamp Server provides images and catalogs for different stages of processing on single exposures, stack images, difference images, and forced photometry. The PSPS is a SQLServer database that can be queried via script or web interface, with a database for each MD field and a large database for the 3pi survey. This database has relative photometry and astrometry and object associations, making it easy to do searches across the entire sky as well as tools to generate lightcurves of individual objects as a function of time.

  15. A-1 Test Stand modifications

    NASA Image and Video Library

    2011-09-14

    Team members check the progress of a liquid nitrogen cold shock test on the A-1 Test Stand at Stennis Space Center on Sept. 15. The cold shock test is used to confirm the test stand's support system can withstand test conditions, when super-cold rocket engine propellant is piped. The A-1 Test Stand is preparing to conduct tests on the powerpack component of the J-2X rocket engine, beginning in early 2012.

  16. 14 CFR 125.373 - Original flight release or amendment of flight release.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Original flight release or amendment of flight release. 125.373 Section 125.373 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... Flight Release Rules § 125.373 Original flight release or amendment of flight release. (a) A certificate...

  17. Neutron-absorber release device

    DOEpatents

    VAN Erp, Jan B.; Kimont, Edward L.

    1976-01-01

    A resettable device is provided for supporting an object, sensing when an environment reaches a critical temperature and releasing the object when the critical temperature is reached. It includes a flexible container having a material inside with a melting point at the critical temperature. The object's weight is supported by the solid material which gives rigidity to the container until the critical temperature is reached at which point the material in the container melts. The flexible container with the now fluid material inside has insufficient strength to support the object which is thereby released. Biasing means forces the container back to its original shape so that when the temperature falls below the melting temperature the material again solidifies, and the object may again be supported by the device.

  18. Zegerid--immediate-release omeprazole.

    PubMed

    2005-04-11

    The FDA has approved marketing of Zegerid powder for oral suspension (Santarus), an immediate-release formulation of the proton-pump inhibitor (PPI) omeprazole (Prilosec, and others). All other oral PPIs are delayed-release, enteric-coated formulations designed to prevent degradation of the drug by gastric acid. Each 20- or 40-mg packet of Zegerid contains 1680 mg sodium bicarbonate, which protects the drug from gastric acid degradation. A dose of Zegerid contains 460 mg of sodium, which may be excessive for some patients. Zegerid is the first oral PPI to be approved by the FDA for reduction of risk of upper GI bleeding in critically ill patients. The drug may be useful for patients who are unable to swallow and have nasogastric (NG) tubes in place. Zegerid cost $70.00 for 14 days' treatment, compared to less than $10 for 14 tablets of Prilosec OTC.

  19. Limited incision carpal tunnel release

    PubMed Central

    Gaba, Sunil; Bhogesha, Sandeep; Singh, Onkar

    2017-01-01

    Background: Carpal tunnel syndrome (CTS) is the most common peripheral entrapment neuropathy. Limited incision techniques for carpal tunnel release are gaining popularity. The main advantages of these techniques are less scar load, less pillar pain, shorter recovery, and return-to-work time. However, the completeness of release, and risk of neurovascular injury are always a concern. We devised a method of limited incision release with two mini-incisions and use of nasal speculum and a probe. We aimed to evaluate the clinical and neurological outcome of this technique. Materials and Methods: Twenty seven cases (9 male and 18 female, age 28–56 years) of isolated CTS cases were enrolled in the study. A total of 33 hands (six bilateral) underwent limited incision carpal tunnel release. In this study, two mini-incisions were used and release was done with the help of nasal speculum. Evaluation preoperatively and in 6 months and at 1-year postoperatively was done, namely, (a) clinical status examination, (b) motor testing using grip and pinch dynamometer, and (c) neurological outcome measure using nerve conduction study. Results: All the patients had good clinical and neurological outcome with no recurrence during followup. The first symptom to get relieved was night pains, with a mean of 4.5 days (range 2–14 days). Compared to pain, improvement of sensory symptoms was delayed; the mean duration was 42.8 days (range 30–90 days). Scar tenderness was present only for a mean duration of 9 days (range 7–21 days). The mean duration for patients to resume their daily activities was12 days (range 7–28 days) and to work was 32 days (range 21–90 days). The hand grip showed mean values of 45.12 ± 16.16 g/mm2 preoperatively, 62.45 ± 18.86 g/mm2 at 6 months postoperatively, and 74.87 ± 20.35 g/mm2 at 1-year postoperatively. The key pinch showed mean values of 11.27 ± 3.51 g/mm2 preoperatively, 20.181 ± 3.94 g/mm2 at 6 months postoperatively, and 27.96 ± 94.42 g/mm2

  20. Limited incision carpal tunnel release.

    PubMed

    Gaba, Sunil; Bhogesha, Sandeep; Singh, Onkar

    2017-01-01

    Carpal tunnel syndrome (CTS) is the most common peripheral entrapment neuropathy. Limited incision techniques for carpal tunnel release are gaining popularity. The main advantages of these techniques are less scar load, less pillar pain, shorter recovery, and return-to-work time. However, the completeness of release, and risk of neurovascular injury are always a concern. We devised a method of limited incision release with two mini-incisions and use of nasal speculum and a probe. We aimed to evaluate the clinical and neurological outcome of this technique. Twenty seven cases (9 male and 18 female, age 28-56 years) of isolated CTS cases were enrolled in the study. A total of 33 hands (six bilateral) underwent limited incision carpal tunnel release. In this study, two mini-incisions were used and release was done with the help of nasal speculum. Evaluation preoperatively and in 6 months and at 1-year postoperatively was done, namely, (a) clinical status examination, (b) motor testing using grip and pinch dynamometer, and (c) neurological outcome measure using nerve conduction study. All the patients had good clinical and neurological outcome with no recurrence during followup. The first symptom to get relieved was night pains, with a mean of 4.5 days (range 2-14 days). Compared to pain, improvement of sensory symptoms was delayed; the mean duration was 42.8 days (range 30-90 days). Scar tenderness was present only for a mean duration of 9 days (range 7-21 days). The mean duration for patients to resume their daily activities was12 days (range 7-28 days) and to work was 32 days (range 21-90 days). The hand grip showed mean values of 45.12 ± 16.16 g/mm(2) preoperatively, 62.45 ± 18.86 g/mm(2) at 6 months postoperatively, and 74.87 ± 20.35 g/mm(2) at 1-year postoperatively. The key pinch showed mean values of 11.27 ± 3.51 g/mm(2) preoperatively, 20.181 ± 3.94 g/mm(2) at 6 months postoperatively, and 27.96 ± 94.42 g/mm(2) at 1-year postoperatively. The tip pinch

  1. Ririe Dam Release Test Assessment

    DTIC Science & Technology

    2013-06-01

    the air temperature record over the course of the Release Test. The coldest air temperatures were recorded around 0700 on 11 February when the air...2012–2013, as shown in Figure 4. The rate of increase was about 1 ft every 15 days. Recording sensors measured reservoir temperatures hourly from 24...November 2012 through 10 February 2013. They recorded the water temperatures at 15 ft intervals between 5000 and 5070 ft, and the data were

  2. Releasing the Results of Investigations

    DTIC Science & Technology

    2010-03-01

    allow for lessons to be learned. RELEASING THE RESULTS OF INVESTIGATIONS On December 21, 2009, Gilbert Arenas – star basketball player for the...National Basketball Association’s Washington Wizards – brought four guns into the locker room at Verizon Center for what he alleged was a practical...joke.1 Earlier in the month Mr. Arenas and teammate Javaris Crittenton – with only two years of NBA experience – “got into an argument over a card

  3. Nanoparticle release from dental composites.

    PubMed

    Van Landuyt, K L; Hellack, B; Van Meerbeek, B; Peumans, M; Hoet, P; Wiemann, M; Kuhlbusch, T A J; Asbach, C

    2014-01-01

    Dental composites typically contain high amounts (up to 60 vol.%) of nanosized filler particles. There is a current concern that dental personnel (and patients) may inhale nanosized dust particles (<100 nm) during abrasive procedures to shape, finish or remove restorations but, so far, whether airborne nanoparticles are released has never been investigated. In this study, composite dust was analyzed in real work conditions. Exposure measurements of dust in a dental clinic revealed high peak concentrations of nanoparticles in the breathing zone of both dentist and patient, especially during aesthetic treatments or treatments of worn teeth with composite build-ups. Further laboratory assessment confirmed that all tested composites released very high concentrations of airborne particles in the nanorange (>10(6)cm(-3)). The median diameter of airborne composite dust varied between 38 and 70 nm. Electron microscopic and energy dispersive X-ray analysis confirmed that the airborne particles originated from the composite, and revealed that the dust particles consisted of filler particles or resin or both. Though composite dust exhibited no significant oxidative reactivity, more toxicological research is needed. To conclude, on manipulation with the bur, dental composites release high concentrations of nanoparticles that may enter deeply into the lungs. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Effects of malathion metabolites on degranulation of and mediator release by human and rat basophilic cells.

    PubMed

    Xiong, S; Rodgers, K

    1997-06-06

    In the present study, the effects of malathion and malathion derivatives on histamine and beta-hexosaminidase release by RBL-1 cells, rat peritoneal mast cells (RPMC), and human peripheral blood basophils (HPBB) and cutaneous mast calls were examined. One hour of incubation of RBL-1 cells with all organophosphate compounds tested, except for malathion and malathion monoacid, led to an increase in histamine release. beta-Hexosaminidase, an enzyme released by basophilic cells and a biochemical marker of degranulation, was not released from RBL-1 cells after 1 h of exposure to organophosphate compounds. Within 4 h, all compounds tested increased the release of histamine and beta-hexosaminidase. Longer exposures led to a decrease in the concentration of the compound that was required to cause mediator release. Exposure of RPMC to organophosphate compounds, with the exception of malathion monoacid and malathion (30 min) or malathion monoacid (1 h), led to the release of histamine, but not beta-hexosaminidase. Incubation of HPBB with malaoxon (51.4 +/- 2.8% total histamine released), malathion diacid (25.7 +/- 2.9%), beta-malathion monoacid (31.4 +/- 2.8%), and isomalathion (57.1 +/- 17.1%) for 1 h led to the release of histamine. Only malaoxon and isomalathion caused beta-hexosaminidase release from HPBB after a 1-h incubation. Incubation of cutaneous mast cells with malaoxon and beta-monoacid for 4 h led to increased release of histamine and beta-hexosaminidase at levels comparable to compound 48/80. These data suggest that malathion metabolites can cause rapid release of histamine from basophilic cells from a variety of origins and species. With prolonged incubation, malathion itself caused the release of mast-cell mediators, suggesting that the cells may be capable of metabolizing malathion. These data also indicate a disparity between the release kinetics of two different mast-cell mediators contained in granules by organophosphates, and that there are different

  5. Identification and analysis of CYP7A1, CYP17A1, CYP20A1, CYP27A1 and CYP51A1 in cynomolgus macaques.

    PubMed

    Uno, Yasuhiro; Hosaka, Shinya; Yamazaki, Hiroshi

    2014-12-01

    Cytochromes P450 (P450) are important for not only drug metabolism and toxicity, but also biosynthesis and metabolism of cholesterol and bile acids, and steroid synthesis. In cynomolgus macaques, widely used in biomedical research, we have characterized P450 cDNAs, which were isolated as expressed sequence tags of cynomolgus macaque liver. In this study, cynomolgus CYP7A1, CYP17A1, CYP20A1, CYP27A1 and CYP51A1 cDNAs were characterized by sequence analysis, phylogenetic analysis and tissue expression pattern. By sequence analysis, these five cynomolgus P450s had high sequence identities (94-99%) to the human orthologs in amino acids. By phylogenetic analysis, each cynomolgus P450 was more closely related to the human ortholog as compared with the dog or rat ortholog. By quantitative polymerase chain reaction, among the 10 tissue types, CYP7A1 and CYP17A1 mRNAs were preferentially expressed in liver and adrenal gland, respectively. Cynomolgus CYP27A1 and CYP51A1 mRNAs were most abundantly expressed in liver and testis, respectively. Cynomolgus CYP20A1 mRNA was expressed in all the tissues, including brain and liver. Tissue expression patterns of each cynomolgus P450 were generally similar to that of the human ortholog. These results suggest the molecular similarities of CYP7A1, CYP17A1, CYP20A1, CYP27A1 and CYP51A1 between cynomolgus macaques and humans.

  6. Fluoride release from restorative materials.

    PubMed

    Basso, Gabriela Romanini; Della Bona, Alvaro; Gobbi, Delton Luiz; Cecchetti, Dileta

    2011-01-01

    The aim of this study was to evaluate in vitro fluoride (F) release from 4 restorative materials (3M ESPE): Ketak Molar Easymix [KME - conventional glass ionomer cement (GIC)]; Rely-X luting 2 [RL2 - resin-modified GIC (RMGIC)]; Vitremer (VIT- RMGIC); and Filtek Z250 [Z250 - negative control]. Disc-shaped specimens were fabricated according to the manufacturer's instructions and placed into 10 mL of reverse osmosis water at 37°C until the analyses were done using a liquid membrane for selective F ion electrode (Orion 710). F release was evaluated every 6 h in the first day and thereafter daily during 28 days (d). The results were analyzed statistically by two-way ANOVA and Tukey's test (α=0.05). Mean F release and standard deviation values (in ppm) were: KME: 6 h- 0.34 ± 0.04; 24 h- 1.22 ± 0.30; 7 d- 0.29 ± 0.09; 14 d- 0.20 ± 0.04; 28 d- 0.16 ± 0.01; RL2: 6 h- 2.46 ± 0.48; 24 h-12.33 ± 2.93; 7 d- 1.37 ± 0.38; 14 d- 0.80 ± 0.13; 28 d- 0.80 ± 0.21; VIT: 6 h- 0.98 ± 0.35; 24 h- 4.35 ± 1.22; 7 d- 0.66 ± 0.23; 14 d- 0.40 ± 0.07; 28 d- 0.39 ± 0.08; Z250: 6 h- 0.029 ± 0.001; 24 h- 0.024 ± 0.009; 7 d- 0.023 ± 0.004; 14 d- 0.025 ± 0.001; 28 d- 0.028 ± 0.001. RL2 RMGIC released more F than the other materials in all periods. The greatest release of F occurred in the first 24 h.

  7. Synapsins Differentially Control Dopamine and Serotonin Release

    PubMed Central

    Kile, Brian M.; Guillot, Thomas S.; Venton, B. Jill; Wetsel, William C.; Augustine, George J.; Wightman, R. Mark

    2010-01-01

    Synapsins are a family of synaptic vesicle proteins that are important for neurotransmitter release. Here we have used triple knockout (TKO) mice lacking all three synapsin genes to determine the roles of synapsins in the release of two monoamine neurotransmitters, dopamine and serotonin. Serotonin release evoked by electrical stimulation was identical in substantia nigra pars reticulata slices prepared from TKO and wild-type mice. In contrast, release of dopamine in response to electrical stimulation was approximately doubled in striatum of TKO mice, both in vivo and in striatal slices, in comparison to wild-type controls. This was due to loss of synapsin III, because deletion of synapsin III alone was sufficient to increase dopamine release. Deletion of synapsins also increased the sensitivity of dopamine release to extracellular calcium ions. Although cocaine did not affect the release of serotonin from nigral tissue, this drug did enhance dopamine release. Cocaine-induced facilitation of dopamine release was a function of external calcium, an effect that was reduced in TKO mice. We conclude that synapsins play different roles in the control of release of dopamine and serotonin, with release of dopamine being negatively regulated by synapsins, specifically synapsin III, while serotonin release appears to be relatively independent of synapsins. These results provide further support for the concept that synapsin function in presynaptic terminals varies according to the neurotransmitter being released. PMID:20660258

  8. Synapsins differentially control dopamine and serotonin release.

    PubMed

    Kile, Brian M; Guillot, Thomas S; Venton, B Jill; Wetsel, William C; Augustine, George J; Wightman, R Mark

    2010-07-21

    Synapsins are a family of synaptic vesicle proteins that are important for neurotransmitter release. Here we have used triple knock-out (TKO) mice lacking all three synapsin genes to determine the roles of synapsins in the release of two monoamine neurotransmitters, dopamine and serotonin. Serotonin release evoked by electrical stimulation was identical in substantia nigra pars reticulata slices prepared from TKO and wild-type mice. In contrast, release of dopamine in response to electrical stimulation was approximately doubled in striatum of TKO mice, both in vivo and in striatal slices, in comparison to wild-type controls. This was due to loss of synapsin III, because deletion of synapsin III alone was sufficient to increase dopamine release. Deletion of synapsins also increased the sensitivity of dopamine release to extracellular calcium ions. Although cocaine did not affect the release of serotonin from nigral tissue, this drug did enhance dopamine release. Cocaine-induced facilitation of dopamine release was a function of external calcium, an effect that was reduced in TKO mice. We conclude that synapsins play different roles in the control of release of dopamine and serotonin, with release of dopamine being negatively regulated by synapsins, specifically synapsin III, while serotonin release appears to be relatively independent of synapsins. These results provide further support for the concept that synapsin function in presynaptic terminals varies according to the neurotransmitter being released.

  9. An enzymatic method for the determination of hemoglobinA(1C).

    PubMed

    Hirokawa, Kozo; Shimoji, Kazuhiko; Kajiyama, Naoki

    2005-07-01

    Fructosyl peptide oxidase is a flavoenzyme that catalyzes the oxidative deglycation of N-(1-deoxyfructosyl)-Val-His, a model compound of hemoglobin (Hb)A(1C). To develop an enzymatic method for the measurement of HbA(1C), we screened for a proper protease using N-(1-deoxyfructosyl)-hexapeptide as a substrate. Several proteases, including Neutral protease from Bacillus polymyxa, were found to release N-(1-deoxyfructosyl)-Val-His efficiently, however no protease was found to release N-(1-deoxyfructosyl)-Val. Neutral protease also digested HbA(1C) to release N-(1-deoxyfructosyl)-Val-His, and then the fructosyl peptide was detected using fructosyl peptide oxidase. The linear relationship was observed between the concentration of HbA(1C) and the absorbancy of fructosyl peptide oxidase reaction, hence this new method is a practical means for measuring HbA(1C.).

  10. Gastrin-releasing peptide stimulates glycoconjugate release from feline trachea

    SciTech Connect

    Lundgren, J.D.; Baraniuk, J.N.; Ostrowski, N.L.; Kaliner, M.A.; Shelhamer, J.H. )

    1990-02-01

    The effect of gastrin-releasing peptide (GRP) on respiratory glycoconjugate (RGC) secretion was investigated in a feline tracheal organ culture model. RGC secretion was stimulated by GRP in a dose-dependent fashion at concentrations from 10(-8) to 10(-5) M (range 15-38% increase above control) with a peak effect within 0.5-1 h of incubation. GRP-(14-27), the receptor binding portion of GRP, and the related molecule, bombesin, also stimulated RGC secretion by approximately 20% above control. Acetyl-GRP-(20-27) stimulated RGC release by 10%, whereas GRP-(1-16) was inactive. Autoradiographic studies with 125I-GRP revealed that specific binding was restricted to the submucosal glands and the surface epithelium. A specific radioimmunoassay showed the content of GRP in feline trachea after extraction with ethanol-acetic acid to be 156 +/- 91 fmol/g wet wt. Indirect immunohistochemistry indicated that ganglion cells located just outside the cartilage contained GRP-immunoreactive materials. GRP is a novel mucus secretagogue that may participate in regulating airway mucosal gland secretion.

  11. Highly loaded, sustained-release microparticles of curcumin for chemoprevention.

    PubMed

    Shahani, Komal; Panyam, Jayanth

    2011-07-01

    Curcumin, a dietary polyphenol, has preventive and therapeutic potential against several diseases. Because of the chronic nature of many of these diseases, sustained-release dosage forms of curcumin could be of significant clinical value. However, extreme lipophilicity and instability of curcumin are significant challenges in its formulation development. The objectives of this study were to fabricate an injectable microparticle formulation that can sustain curcumin release over a 1-month period and to determine its chemopreventive activity in a mouse model. Microparticles were fabricated using poly(D, L-lactide-co-glycolide) polymer. Conventional emulsion solvent evaporation method of preparing microparticles resulted in crystallization of curcumin outside of microparticles and poor entrapment (∼1%, w/w loading). Rapid solvent removal using vacuum dramatically increased drug entrapment (∼38%, w/w loading; 76% encapsulation efficiency). Microparticles sustained curcumin release over 4 weeks in vitro, and drug release rate could be modulated by varying the polymer molecular weight and/or composition. A single subcutaneous dose of microparticles sustained curcumin liver concentration for nearly a month in mice. Hepatic glutathione-s-transferase and cyclooxygenase-2 activities, biomarkers for chemoprevention, were altered following treatment with curcumin microparticles. The results of these studies suggest that sustained-release microparticles of curcumin could be a novel and effective approach for cancer chemoprevention. Copyright © 2011 Wiley-Liss, Inc. and the American Pharmacists Association

  12. Highly Loaded, Sustained-Release Microparticles of Curcumin for Chemoprevention

    PubMed Central

    SHAHANI, KOMAL; PANYAM, JAYANTH

    2014-01-01

    Curcumin, a dietary polyphenol, has preventive and therapeutic potential against several diseases. Because of the chronic nature of many of these diseases, sustained-release dosage forms of curcumin could be of significant clinical value. However, extreme lipophilicity and instability of curcumin are significant challenges in its formulation development. The objectives of this study were to fabricate an injectable microparticle formulation that can sustain curcumin release over a 1-month period and to determine its chemopreventive activity in a mouse model. Microparticles were fabricated using poly(D, L-lactide-co-glycolide) polymer. Conventional emulsion solvent evaporation method of preparing microparticles resulted in crystallization of curcumin outside of microparticles and poor entrapment (~1%, w/w loading). Rapid solvent removal using vacuum dramatically increased drug entrapment (~38%, w/w loading; 76% encapsulation efficiency). Microparticles sustained curcumin release over 4 weeks in vitro, and drug release rate could be modulated by varying the polymer molecular weight and/or composition. A single subcutaneous dose of microparticles sustained curcumin liver concentration for nearly a month in mice. Hepatic glutathione-s-transferase and cyclooxygenase-2 activities, biomarkers for chemoprevention, were altered following treatment with curcumin microparticles. The results of these studies suggest that sustained-release microparticles of curcumin could be a novel and effective approach for cancer chemoprevention. PMID:21547911

  13. Hermes A-1 Test Rockets

    NASA Technical Reports Server (NTRS)

    1950-01-01

    The first Hermes A-1 test rocket was fired at White Sand Proving Ground (WSPG). Hermes was a modified V-2 German rocket, utilizing the German aerodynamic configuration; however, internally it was a completely new design. Although it did not result in an operational vehicle, the information that was gathered in the process contributed directly to the development of the Redstone rocket.

  14. Modified pipe extension safely releases chain binders

    NASA Technical Reports Server (NTRS)

    Haw, D. W.

    1978-01-01

    Pipe, cut partly in half lengthwise, and cupped and notched at one end, safely releases tension in chain binders that cinch tiedown chains around truck loads. Device prevents binder-handle from being thrown violently during release.

  15. Section 9: Ground Water - Likelihood of Release

    EPA Pesticide Factsheets

    HRS training. the ground water pathway likelihood of release factor category reflects the likelihood that there has been, or will be, a release of hazardous substances in any of the aquifers underlying the site.

  16. Safety Precautions for Total Release Foggers

    EPA Pesticide Factsheets

    Total release foggers, also known as bug bombs, are pesticide products containing aerosol propellants that release their contents at once to fumigate an area. They can pose a hazard if used incorrectly. Find safety information and videos on this page.

  17. Mars Express releases Beagle 2

    NASA Astrophysics Data System (ADS)

    2003-12-01

    At 9:31 CET, the crucial sequence started to separate the Beagle 2 lander from Mars Express. As data from Mars Express confirm, the pyrotechnic device was fired to slowly release a loaded spring, which gently pushed Beagle 2 away from the mother spacecraft. An image from the onboard visual monitoring camera (VMC) showing the lander drifting away is expected to be available later today. Since the Beagle 2 lander has no propulsion system of its own, it had to be put on the correct course for its descent before it was released. For this reason, on 16 December the trajectory of the whole Mars Express spacecraft had to be adjusted to ensure that Beagle 2 would be on course to enter the atmosphere of Mars. This manoeuvre, called "retargeting'' was critical: if the entry angle is too steep, the lander could overheat and burn up in the atmosphere; if the angle is too shallow, the lander might skim like a pebble on the surface of a lake and miss its target. This fine targeting and today's release were crucial manoeuvres for which ESA's Ground Control Team at ESOC (European Space Operations Centre) had trained over the past several months. The next major milestone for Mars Express will be the manoeuvre to enter into orbit around Mars. This will happen at 3:52 CET on Christmas morning, when Beagle 2 is expected to land on the surface of Mars. "Good teamwork by everybody - ESA, industry and the Beagle 2 team - has got one more critical step accomplished. Mars, here comes Europe!" said David Southwood, ESA Director of Science.

  18. Influence of Carbopol 71G-NF on the release of dextromethorphan hydrobromide from extended-release matrix tablets.

    PubMed

    Fayed, Mohamed H; Mahrous, Gamal M; Ibrahim, Mohamed A; Sakr, Adel

    2013-01-01

    The objective of this study was to evaluate the potential of Carbopol(®) 71G-NF on the release of dextromethorphan hydrobromide (DM) from matrix tablets in comparison with hydroxypropyl methylcellulose (HPMC(®) K15M) and Eudragit(®) L100-55 polymers. Controlled release DM matrix tablets were prepared using Carbopol 71G-NF, HPMC K15M, and Eudragit L100-55 at different drug to polymer ratios by direct compression technique. The mechanical properties of the tablets as tested by crushing strength and friability tests were improved as the concentration of Carbopol, HPMC, and Eudragit increased. However, Carbopol-based tablets showed a significantly (P<0.05) higher crushing strength and a lower friability than HPMC and Eudragit tablets. No significant differences in weight uniformity and thickness values were observed between the different formulations. It was also found that Carbopol significantly (P<0.05) delayed the release of DM in comparison with HPMC K15M and Eudragit L100-55. A combination of HPMC K15M and Eudragit L100-55 in a 1:1 ratio at 20 and 30% significantly (P<0.05) delayed the release of DM than Eudragit L100-55 alone. Moreover, blends of Carbopol and HPMC at a 1:1 ratio at the 10, 20, and 30% total polymer concentration were investigated. The blend of Carbopol and HPMC at 10% level significantly (P<0.05) slowed the release of DM than Carbopol or HPMC alone, whereas blends at 20 and 30% level significantly (P<0.05) delayed the release of DM compared with HPMC or Carbopol alone. The results with these polymer blends showed that it was possible to reduce the total amount of polymers when used as a combination in formulation.

  19. Renin release: role of SNAREs.

    PubMed

    Mendez, Mariela

    2014-09-01

    Little is known about the molecular mechanism mediating renin granule exocytosis and the identity of proteins involved. We previously showed that soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNAREs), a family of proteins required for exocytosis, mediate the stimulated release of renin from juxtaglomerular cells. This minireview focuses on the current knowledge of the proteins that facilitate renin-granule exocytosis. We discuss the identity of potential candidates that mediate the signaling and final steps of exocytosis of the renin granule. Copyright © 2014 the American Physiological Society.

  20. Pediatric Trigger Digits.

    PubMed

    Bauer, Andrea S; Bae, Donald S

    2015-11-01

    Pediatric trigger thumb presents not at birth but early in childhood. Most evidence suggests that it is caused by a developmental size mismatch between the flexor pollicis longus tendon and its sheath. Patients generally present with the thumb interphalangeal joint locked in flexion. Surgical reviews report near universally excellent outcomes after open release of the A1 pulley. However, recent reports indicate that there may be a role for nonsurgical treatment for families that are willing to wait several years for possible spontaneous resolution of the deformity. Triggering in digits other than the thumb in children is generally associated with an underlying diagnosis including anatomic abnormalities of the tendons, and metabolic, inflammatory, and infectious etiologies. Although some have advocated nonsurgical treatment, surgery is often necessary to address the underlying anatomic etiology. More extensive surgery beyond simple A1 pulley release is often required, including release of the A3 pulley and resection of a slip of the flexor digitorum superficialis tendon. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  1. 28 CFR 2.33 - Release plans.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS, YOUTH OFFENDERS... of parole is conditioned upon the approval of release plans by the Regional Commissioner. In general... reasonable plan for payment shall, where feasible, be included in the parole release plan....

  2. 28 CFR 2.33 - Release plans.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS, YOUTH OFFENDERS... of parole is conditioned upon the approval of release plans by the Regional Commissioner. In general... reasonable plan for payment shall, where feasible, be included in the parole release plan....

  3. 28 CFR 2.33 - Release plans.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Release plans. 2.33 Section 2.33 Judicial..., AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees § 2.33 Release plans. (a) A grant of parole is conditioned upon the approval of release plans by the Regional Commissioner. In...

  4. 46 CFR 108.457 - Pressure release.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure release. 108.457 Section 108.457 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.457 Pressure release... have a means for releasing pressure that accumulates within the space if CO2 is discharged into...

  5. 46 CFR 108.457 - Pressure release.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Pressure release. 108.457 Section 108.457 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.457 Pressure release... have a means for releasing pressure that accumulates within the space if CO2 is discharged into...

  6. 46 CFR 108.457 - Pressure release.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Pressure release. 108.457 Section 108.457 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.457 Pressure release... have a means for releasing pressure that accumulates within the space if CO2 is discharged into...

  7. 46 CFR 108.457 - Pressure release.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure release. 108.457 Section 108.457 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.457 Pressure release... have a means for releasing pressure that accumulates within the space if CO2 is discharged into...

  8. 46 CFR 108.457 - Pressure release.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure release. 108.457 Section 108.457 Shipping COAST... Fire Extinguishing Systems Fixed Carbon Dioxide Fire Extinguishing Systems § 108.457 Pressure release... have a means for releasing pressure that accumulates within the space if CO2 is discharged into...

  9. 34 CFR 21.61 - Release.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 34 Education 1 2012-07-01 2012-07-01 false Release. 21.61 Section 21.61 Education Office of the Secretary, Department of Education EQUAL ACCESS TO JUSTICE How Are Awards Paid? § 21.61 Release. If an...; and (b) Constitutes a complete release of any further claim against the United States with respect...

  10. 34 CFR 21.61 - Release.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Release. 21.61 Section 21.61 Education Office of the Secretary, Department of Education EQUAL ACCESS TO JUSTICE How Are Awards Paid? § 21.61 Release. If an...; and (b) Constitutes a complete release of any further claim against the United States with respect...

  11. 34 CFR 21.61 - Release.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 34 Education 1 2014-07-01 2014-07-01 false Release. 21.61 Section 21.61 Education Office of the Secretary, Department of Education EQUAL ACCESS TO JUSTICE How Are Awards Paid? § 21.61 Release. If an...; and (b) Constitutes a complete release of any further claim against the United States with respect...

  12. 34 CFR 21.61 - Release.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 1 2011-07-01 2011-07-01 false Release. 21.61 Section 21.61 Education Office of the Secretary, Department of Education EQUAL ACCESS TO JUSTICE How Are Awards Paid? § 21.61 Release. If an...; and (b) Constitutes a complete release of any further claim against the United States with respect...

  13. 34 CFR 21.61 - Release.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 1 2013-07-01 2013-07-01 false Release. 21.61 Section 21.61 Education Office of the Secretary, Department of Education EQUAL ACCESS TO JUSTICE How Are Awards Paid? § 21.61 Release. If an...; and (b) Constitutes a complete release of any further claim against the United States with respect...

  14. Individualized optimal release angles in discus throwing.

    PubMed

    Leigh, Steve; Liu, Hui; Hubbard, Mont; Yu, Bing

    2010-02-10

    The purpose of this study was to determine individualized optimal release angles for elite discus throwers. Three-dimensional coordinate data were obtained for at least 10 competitive trials for each subject. Regression relationships between release speed and release angle, and between aerodynamic distance and release angle were determined for each subject. These relationships were linear with subject-specific characteristics. The subject-specific relationships between release speed and release angle may be due to subjects' technical and physical characteristics. The subject-specific relationships between aerodynamic distance and release angle may be due to interactions between the release angle, the angle of attack, and the aerodynamic distance. Optimal release angles were estimated for each subject using the regression relationships and equations of projectile motion. The estimated optimal release angle was different for different subjects, and ranged from 35 degrees to 44 degrees . The results of this study demonstrate that the optimal release angle for discus throwing is thrower-specific. The release angles used by elite discus throwers in competition are not necessarily optimal for all discus throwers, or even themselves. The results of this study provide significant information for understanding the biomechanics of discus throwing techniques.

  15. 19 CFR 142.48 - Release procedure.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Release procedure. 142.48 Section 142.48 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) ENTRY PROCESS Line Release § 142.48 Release procedure. (a) General. When the Customs officer...

  16. 28 CFR 2.33 - Release plans.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 1 2012-07-01 2012-07-01 false Release plans. 2.33 Section 2.33 Judicial..., AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees § 2.33 Release plans. (a) A grant of parole is conditioned upon the approval of release plans by the Regional Commissioner. In...

  17. 28 CFR 2.33 - Release plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Release plans. 2.33 Section 2.33 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS, YOUTH OFFENDERS, AND JUVENILE DELINQUENTS United States Code Prisoners and Parolees § 2.33 Release plans. (a) A...

  18. How Newspapers Choose the Releases They Use.

    ERIC Educational Resources Information Center

    Morton, Linda P.

    1986-01-01

    Examines how four newspaper characteristics and seven types of news releases related to publications. Concludes that weekly and twice-weekly newspapers print more releases than daily papers and that past events, features, and institutional news releases are almost never printed. (SRT)

  19. Redesigning reservoir compensation releases for ecological beenfit

    NASA Astrophysics Data System (ADS)

    Maynard, Carly

    2010-05-01

    River regulation is commonplace in England and much of the UK. Regulation for the purposes of public water supply causes flows downstream of a reservoir to be attenuated and the flow regime of the channel to be altered. The impact of channel impoundment on a small, upland UK river, has been assessed and methods for mitigation of ecological impacts explored. The method utilised a unique macroinvertebrate data set for pre- and post-impoundment periods to quantify the impact of Derwent Reservoir and the steady, continuous compensation release into the River Derwent, Northumberland. Impacts on the hydrological regime were also investigated and links drawn between changes in flow regime and changes in macroinvertebrate richness and diversity as a result of impoundment. In response to the claim that the impoundment has caused a change in flow regime and had deleterious effects on fish and macroinvertebrates, a compensation redesign tool (CRAB: Compensation Release Assessment at the Broad scale) was employed to design new compensation release regimes from the reservoir which account for the seasonal flow requirements of a number of key fish species. The impact of impoundment on the current flow regime was modelled and the impacts of predicted new regimes were predicted, using a 1D hydrodynamic model (HEC-RAS), as part of a modelling process known as CRAM (Compensation Release Assessment at the Meso-scale). Depth and velocity were the foci of the analysis as they are the two habitat requirements most well documented for the fish species in question, they could be modelled using HEC-RAS and they can act as surrogates for other habitat parameters such as temperature and substrate. The suitability of the depth and velocity combinations predicted using the HEC-RAS model were assessed using fuzzy-rule based modelling, which allowed the habitat quality of a given parameter combination to be quantified. Based on the results of the investigation it was concluded that there has

  20. Gas release in comet nuclei.

    PubMed

    Prialnik, D; Bar-Nun, A

    1990-11-01

    The evolution of a comet nucleus is investigated, taking into account the crystallization process by which the gas trapped in the ice is released to flow through the porous ice matrix. The equations of conservation of the energy and of the masses of ice and gas are solved throughout the nucleus, to obtain the evolution of the temperature, gas pressure and density profiles. A spherical nucleus composed of cold, porous amorphous ice, with 10% of CO trapped in it, serves as initial model. Several values of density (porosity) and pore size are considered. For each combination of parameters the model is evolved for 20-30 revolutions in comet P/Halley's orbit. Two aspects of the release of gas upon crystallization are analyzed and discussed: (a) the resulting continuous outward flux with high peaks at the time of crystallization, which is a cyclic process in the low-density models and sporadic in the high-density ones; (b) the internal pressures obtained down to depths of a few tens to approximately 200 m (depending on parameters), that are found to exceed the compressional strength of cometary ice. As a result, both cracking and explosions of the overlying ice layer and ejection of gas and ice/dust grains are expected to follow crystallization. They should appear as outbursts or sudden brightening of the comet. The model of 0.2 g cm-3 density is found to reproduce quite well many of the light-curve and activity characteristics of comet P/Halley.

  1. Nuclear energy release from fragmentation

    NASA Astrophysics Data System (ADS)

    Li, Cheng; Souza, S. R.; Tsang, M. B.; Zhang, Feng-Shou

    2016-08-01

    It is well known that binary fission occurs with positive energy gain. In this article we examine the energetics of splitting uranium and thorium isotopes into various numbers of fragments (from two to eight) with nearly equal size. We find that the energy released by splitting 230,232Th and 235,238U into three equal size fragments is largest. The statistical multifragmentation model (SMM) is applied to calculate the probability of different breakup channels for excited nuclei. By weighing the probability distributions of fragment multiplicity at different excitation energies, we find the peaks of energy release for 230,232Th and 235,238U are around 0.7-0.75 MeV/u at excitation energy between 1.2 and 2 MeV/u in the primary breakup process. Taking into account the secondary de-excitation processes of primary fragments with the GEMINI code, these energy peaks fall to about 0.45 MeV/u.

  2. Antiprogestin-releasing intrauterine devices

    PubMed Central

    Nayak, NR; Slayden, OD; Mah, K; Chwalisz, K; Brenner, Robert M

    2007-01-01

    Intrauterine devices (IUDs) that release progestins are highly effective contraceptives, but they induce breakthrough bleeding that some women find unacceptable. Because progesterone (P) antagonists (AP) are known to suppress the endometrium, induce amenorrhea, and inhibit fertility, AP IUDs may provide an effective contraceptive that also controls endometrial bleeding. Here we assessed the effects of empty (blank) vs AP-releasing (ZK 230 211) IUDs on bleeding patterns and endometrial growth in ovariectomized, artificially cycled macaques. The AP IUDs (but not the blank controls) induced extended, frank menstruation when inserted during the late luteal phase, an indication of local AP action. Over time, endometrial glandular and arterial proliferation were inhibited, steroid receptors were elevated, spiral arteries showed degenerative changes, progesterone withdrawal bleeding was prevented and estradiol-dependent proliferation was suppressed by the AP IUDs. In sum, AP IUDs suppressed the effects of P on endometrial progestational development and blocked the effects of estradiol on endometrial proliferation as previously shown for systemic treatment with APs. Therefore, AP IUDs may provide novel contraceptive devices with minimal breakthrough bleeding. PMID:17531599

  3. Calcium Control of Neurotransmitter Release

    PubMed Central

    Südhof, Thomas C.

    2012-01-01

    Upon entering a presynaptic terminal, an action potential opens Ca2+ channels, and transiently increases the local Ca2+ concentration at the presynaptic active zone. Ca2+ then triggers neurotransmitter release within a few hundred microseconds by activating synaptotagmins Ca2+. Synaptotagmins bind Ca2+ via two C2-domains, and transduce the Ca2+ signal into a nanomechanical activation of the membrane fusion machinery; this activation is mediated by the Ca2+-dependent interaction of the synaptotagmin C2-domains with phospholipids and SNARE proteins. In triggering exocytosis, synaptotagmins do not act alone, but require an obligatory cofactor called complexin, a small protein that binds to SNARE complexes and simultaneously activates and clamps the SNARE complexes, thereby positioning the SNARE complexes for subsequent synaptotagmin action. The conserved function of synaptotagmins and complexins operates generally in most, if not all, Ca2+-regulated forms of exocytosis throughout the body in addition to synaptic vesicle exocytosis, including in the degranulation of mast cells, acrosome exocytosis in sperm cells, hormone secretion from endocrine cells, and neuropeptide release. PMID:22068972

  4. ATP release through pannexon channels

    PubMed Central

    Dahl, Gerhard

    2015-01-01

    Extracellular adenosine triphosphate (ATP) serves as a signal for diverse physiological functions, including spread of calcium waves between astrocytes, control of vascular oxygen supply and control of ciliary beat in the airways. ATP can be released from cells by various mechanisms. This review focuses on channel-mediated ATP release and its main enabler, Pannexin1 (Panx1). Six subunits of Panx1 form a plasma membrane channel termed ‘pannexon’. Depending on the mode of stimulation, the pannexon has large conductance (500 pS) and unselective permeability to molecules less than 1.5 kD or is a small (50 pS), chloride-selective channel. Most physiological and pathological stimuli induce the large channel conformation, whereas the small conformation so far has only been observed with exclusive voltage activation of the channel. The interaction between pannexons and ATP is intimate. The pannexon is not only the conduit for ATP, permitting ATP efflux from cells down its concentration gradient, but the pannexon is also modulated by ATP. The channel can be activated by ATP through both ionotropic P2X as well as metabotropic P2Y purinergic receptors. In the absence of a control mechanism, this positive feedback loop would lead to cell death owing to the linkage of purinergic receptors with apoptotic processes. A control mechanism preventing excessive activation of the purinergic receptors is provided by ATP binding (with low affinity) to the Panx1 protein and gating the channel shut. PMID:26009770

  5. Fully redundant mechanical release actuator

    NASA Technical Reports Server (NTRS)

    Lucy, Melvin H. (Inventor)

    1987-01-01

    A system is described for performing a mechanical release function exhibiting low shock. This system includes two pyrotechnic detents fixed mounted in opposing axial alignment within a cylindrical housing having two mechanical bellows. Two mechanical bellow assemblies, each having one end hermetically bonded to the housing and the other to the respective actuator pin extending from either end of the housing, ensure that all outgassing and contamination from the operation of the pyrotechnic devices will be contained within the housing and bellows. The pin on one end of the assembly is fixed mounted and supported, via a bolt or ball-and-socket joint so that when the charge corresponding to that pin ignites, the entire assembly will exhibit rectilinear movement, including the opposing pin providing the unlatching motion. The release detent pin is supported by a linear bearing and when its corresponding pyrotechnic charge ignites the pin is retracted within the housing producing the same unlatching motion without movement of the entire assembly, thus providing complete mechanical, electrical and pyrotechnic redundancy for the unlatching pin.

  6. Foamy Virus Budding and Release

    PubMed Central

    Hütter, Sylvia; Zurnic, Irena; Lindemann, Dirk

    2013-01-01

    Like all other viruses, a successful egress of functional particles from infected cells is a prerequisite for foamy virus (FV) spread within the host. The budding process of FVs involves steps, which are shared by other retroviruses, such as interaction of the capsid protein with components of cellular vacuolar protein sorting (Vps) machinery via late domains identified in some FV capsid proteins. Additionally, there are features of the FV budding strategy quite unique to the spumaretroviruses. This includes secretion of non-infectious subviral particles and a strict dependence on capsid-glycoprotein interaction for release of infectious virions from the cells. Virus-like particle release is not possible since FV capsid proteins lack a membrane-targeting signal. It is noteworthy that in experimental systems, the important capsid-glycoprotein interaction could be bypassed by fusing heterologous membrane-targeting signals to the capsid protein, thus enabling glycoprotein-independent egress. Aside from that, other systems have been developed to enable envelopment of FV capsids by heterologous Env proteins. In this review article, we will summarize the current knowledge on FV budding, the viral components and their domains involved as well as alternative and artificial ways to promote budding of FV particle structures, a feature important for alteration of target tissue tropism of FV-based gene transfer systems. PMID:23575110

  7. Release of gastrointestinal regulatory peptides after a soap enema.

    PubMed

    Jenssen, T G; Burhol, P G; Jorde, R

    1985-08-01

    A 1-l soap enema given to nine healthy volunteers elicited significantly elevated plasma levels of vasoactive intestinal polypeptide (VIP) and cholecystokinin (CCK), together with a transient somatostatin peak. These rises coincided with significant rises both in systolic and diastolic blood pressure, whereas plasma levels of motilin and pancreatic polypeptide remained unchanged. It is suggested that the peptide releases are of colonic origin and that VIP and CCK may play mediatory roles in the enema-induced defecation.

  8. Flouride release from various restorative materials.

    PubMed

    Bala, O; Uçtaşli, M; Can, H; Türköz, E; Can, M

    1997-09-01

    Fluoride release from six light-activated restorative materials, including two resinmodified glass-ionomers, two composites, and two compomers, was evaluated and compared with one conventional acid-based glass-ionomer cement. The amount and rate of release varied among the tested materials. Both resin-modified glass-ionomers and the conventional acid-base glass-ionomer cements released more fluoride then the composites and compomers (p < 0.05). Additionally, composite materials released less fluoride than compomer materials (p < 0.05). Release of fluoride by the tested materials showed a significant decrease after all the tested time intervals.

  9. Resection of the flexor digitorum superficialis for trigger finger with proximal interphalangeal joint positional contracture.

    PubMed

    Favre, Yann; Kinnen, Louis

    2012-11-01

    Open release of the A1 pulley is a widely known procedure for the treatment of trigger finger. A subset of patients presents with both trigger finger and a positional contracture of the proximal interphalangeal (PIP) joint. These patients usually have a long history of trigger finger or have already undergone a surgical release of the annular pulley. This study is a retrospective review of the outcomes of resection of the flexor digitorum superficialis (FDS) for patients whose trigger finger was associated with a positional contracture of the PIP joint. Thirty-six patients (39 fingers) were treated by resection of the FDS after section of the A1 pulley. The mean age of the patients was 63 years (range, 45-90 y). Seven patients (19 %) had previously undergone an open release of the A1 pulley and had developed a positional contracture of the PIP joint 2 to 5 months afterward. We performed a retrospective review with a mean follow-up of 30 months (range, 12-60 mo). No patient was lost to follow-up. The active range of motion was recorded at the PIP joint before and after surgery. The mean preoperative positional contracture of the PIP joint was 24° (range, 15°-30°). The mean postoperative positional contracture of the PIP joint was 4° (range, 0°-10°). The most commonly affected digit was the middle finger (26 fingers, 67%). In 28 fingers (72%), full extension was achieved following only the surgical procedure. The remaining 11 fingers (28%) had a postoperative residual positional contracture (range, 5°-10°). However, all fingers achieved a full range of motion after physical therapy and an injection of betamethasone. All of the resected tendons had histological damage. This technique is a useful treatment for selected patients whose trigger finger is associated with a positional contracture. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  10. A rapid technique for prediction of nutrient release from controlled release fertilizers

    USDA-ARS?s Scientific Manuscript database

    Nutrient release from soluble granular fertilizers can be modified by polymer coating to extend the total duration nutrient release up to 3 to 9 months and rate of release to match the nutrient requirement of the plant during the growing period. Hence these products are termed as “Controlled Release...

  11. Controlled Drug Release from Pharmaceutical Nanocarriers

    PubMed Central

    Lee, Jinhyun Hannah; Yeo, Yoon

    2014-01-01

    Nanocarriers providing spatiotemporal control of drug release contribute to reducing toxicity and improving therapeutic efficacy of a drug. On the other hand, nanocarriers face unique challenges in controlling drug release kinetics, due to the large surface area per volume ratio and the short diffusion distance. To develop nanocarriers with desirable release kinetics for target applications, it is important to understand the mechanisms by which a carrier retains and releases a drug, the effects of composition and morphology of the carrier on the drug release kinetics, and current techniques for preparation and modification of nanocarriers. This review provides an overview of drug release mechanisms and various nanocarriers with a specific emphasis on approaches to control the drug release kinetics. PMID:25684779

  12. Decommissioning Project of Bohunice A1 NPP

    SciTech Connect

    Stubna, M.; Pekar, A.; Moravek, J.; Spirko, M.

    2002-02-26

    The first (pilot) nuclear power plant A1 in the Slovak Republic, situated on Jaslovske Bohunice site (60 km from Bratislava) with the capacity of 143 MWel, was commissioned in 1972 and was running with interruptions till 1977. A KS 150 reactor (HWGCR) with natural uranium as fuel, D2O as moderator and gaseous CO2 as coolant was installed in the A1 plant. Outlet steam from primary reactor coolant system with the temperature of 410 C was led to 6 modules of steam generators and from there to turbine generators. Refueling was carried out on-line at plant full power. The first serious incident associated with refueling occurred in 1976 when a locking mechanism at a fuel assembly failed. The core was not damaged during that incident and following a reconstruction of the damaged technology channel, the plant continued in operation. However, serious problems were occurring with the integrity of steam generators (CO2 gas on primary side, water and steam on secondary side) when the plant had to be shut down frequently due to failures and subsequent repairs. The second serious accident occurred in 1977 when a fuel assembly was overheated with a subsequent release of D2O into gas cooling circuit due to a human failure in the course of replacement of a fuel assembly. Subsequent rapid increase in humidity of the primary system resulted in damages of fuel elements in the core and the primary system was contaminated by fission products. In-reactor structures had been damaged, too. Activity had penetrated also into certain parts of the secondary system via leaking steam generators. Radiation situation in the course of both events on the plant site and around it had been below the level of limits specified. Based on a technical and economical justification of the demanding character of equipment repairs for the restoration of plant operation, and also due to a decision made not to continue with further construction of gas cooled reactors in Czechoslovakia, a decision was made in

  13. Characterization of tritiated noradrenaline release from the rat preoptic area with microdialysis in vivo.

    PubMed

    Fernández-Galaz, C; Herbison, A E; Dyer, R G

    1993-05-01

    Present techniques are unable to provide a sensitive and accurate index of noradrenergic activity in the rat preoptic area. In this study, we have examined the brainstem A1 noradrenergic input to the preoptic area using a new technique whereby [3H]noradrenaline is preloaded into the preoptic area and release of radioactivity from this region is measured subsequently using microdialysis in vivo. Electrical stimulation of the ipsilateral A1 area for 20 min at 5, 10, and 15 Hz evoked significant increases in dialysate radioactivity that were repeatable and frequency-dependent. After removal of calcium from the perfusion medium, basal release of radioactivity was markedly reduced and the effect of A1 stimulation abolished. Changing to a 100 mM K+ medium evoked an increase in the release of radioactivity that was sixfold greater than that seen after A1 stimulation. Separation of the dialysate with HPLC showed that 33% of the increase in measured radioactivity after A1 stimulation was directly attributable to [3H]noradrenaline and the remainder to the metabolites vanillylmandelic acid, 3,4-dihydroxymandelic acid, and 3,4-dihydroxyphenylglycol. In contrast, the increase in radioactivity after K+ depolarization was due almost completely to [3H]noradrenaline. Addition of 10 microM clonidine to the perfusion medium markedly reduced basal release of radioactivity, but had no effect on evoked release following A1 stimulation. Conversely, perfusion with 10 microM yohimbine had no effect on basal release, but significantly increased evoked release after A1 stimulation. These results now provide a characterization of noradrenergic activity in the preoptic area and indicate the importance of the A1 noradrenergic input to this region. The technique of measuring radioactivity with microdialysis after preloading with [3H]noradrenaline provides a relatively simple, sensitive index of noradrenergic activity in vivo with good temporal resolution.

  14. Study on novel galantaminehydrobromide sustained-release capsules and itsin vitro releasing property.

    PubMed

    Li, Kun; Yang, Shuoye

    2014-09-01

    In present study, we prepared a novel galantamine hydro bromide sustained-release capsules with the new manufacturing technology, extrusion-spheronization method, and the optimized preparative formulation. A simple, rapid and accurate high performance liquid chromatography method (HPLC) was developed and validated for the quantification and release evaluation of galantamine hydro bromide. Experimental results showed that the method was specific, sensitive and reliable, could be effectively applied to the in vitro release study of galantamine hydro bromide sustained-release capsules. Our resulting samples had superior properties, worked better as sustained-release carriers and lasted longer hours to release drugs compared with the marketed control, Razadyne ER. The in vitro releasing characteristics of different batches of preparations are quite similar with each other, the total release proportions of galantamine hydro bromide from sustained-release capsules reached higher than 90 % within 12 h. The testing sustained-release preparation may be a promising new product for curing the related diseases.

  15. Release of canine parvovirus from endocytic vesicles.

    PubMed

    Suikkanen, Sanna; Antila, Mia; Jaatinen, Anne; Vihinen-Ranta, Maija; Vuento, Matti

    2003-11-25

    Canine parvovirus (CPV) is a small nonenveloped virus with a single-stranded DNA genome. CPV enters cells by clathrin-mediated endocytosis and requires an acidic endosomal step for productive infection. Virion contains a potential nuclear localization signal as well as a phospholipase A(2) like domain in N-terminus of VP1. In this study we characterized the role of PLA(2) activity on CPV entry process. PLA(2) activity of CPV capsids was triggered in vitro by heat or acidic pH. PLA(2) inhibitors inhibited the viral proliferation suggesting that PLA(2) activity is needed for productive infection. The N-terminus of VP1 was exposed during the entry, suggesting that PLA(2) activity might have a role during endocytic entry. The presence of drugs modifying endocytosis (amiloride, bafilomycin A(1), brefeldin A, and monensin) caused viral proteins to remain in endosomal/lysosomal vesicles, even though the drugs were not able to inhibit the exposure of VP1 N-terminal end. These results indicate that the exposure of N-terminus of VP1 alone is not sufficient to allow CPV to proliferate. Some other pH-dependent changes are needed for productive infection. In addition to blocking endocytic entry, amiloride was able to block some postendocytic steps. The ability of CPV to permeabilize endosomal membranes was demonstrated by feeding cells with differently sized rhodamine-conjugated dextrans together with the CPV in the presence or in the absence of amiloride, bafilomycin A(1), brefeldin A, or monensin. Dextran with a molecular weight of 3000 was released from vesicles after 8 h of infection, while dextran with a molecular weight of 10,000 was mainly retained in vesicles. The results suggest that CPV infection does not cause disruption of endosomal vesicles. However, the permeability of endosomal membranes apparently changes during CPV infection, probably due to the PLA(2) activity of the virus. These results suggest that parvoviral PLA(2) activity is essential for productive

  16. Controlled release of subretinal fluid.

    PubMed

    Martin, B

    1975-01-01

    Drainage os subretinal fluid is generally regarded as being unnecessary when local buckling procedures are carried out, particularly when the buckle is placed radially, unless the patient has chronic glaucoma or the choroidal vessels are markedly sclerosed.However, there are many cases of retinal detachment where the eye is otherwise normal and where radial procedure is the detachment operation of choice in which a limited and controlled release of subretinal fluid will help considerably in the localisation, treatment by cryotherapy and final positioning of the tear on the buckle. This paper describes the technique employed and the advantages which may be gained by using this method in cases of deep bullous detachment of the retina. The results which have been obtained in cases in which this method has been used during the last 3 years are described.

  17. Release of RANKERN 16A

    NASA Astrophysics Data System (ADS)

    Bird, Adam; Murphy, Christophe; Dobson, Geoff

    2017-09-01

    RANKERN 16 is the latest version of the point-kernel gamma radiation transport Monte Carlo code from AMEC Foster Wheeler's ANSWERS Software Service. RANKERN is well established in the UK shielding community for radiation shielding and dosimetry assessments. Many important developments have been made available to users in this latest release of RANKERN. The existing general 3D geometry capability has been extended to include import of CAD files in the IGES format providing efficient full CAD modelling capability without geometric approximation. Import of tetrahedral mesh and polygon surface formats has also been provided. An efficient voxel geometry type has been added suitable for representing CT data. There have been numerous input syntax enhancements and an extended actinide gamma source library. This paper describes some of the new features and compares the performance of the new geometry capabilities.

  18. Biomediated continuous release phosphate fertilizer

    DOEpatents

    Goldstein, A.H.; Rogers, R.D.

    1999-06-15

    A composition is disclosed for providing phosphate fertilizer to the root zone of plants. The composition comprises a microorganism capable of producing and secreting a solubilization agent, a carbon source for providing raw material for the microorganism to convert into the solubilization agent, and rock phosphate ore for providing a source of insoluble phosphate that is solubilized by the solubilization agent and released as soluble phosphate. The composition is provided in a physical form, such as a granule, that retains the microorganism, carbon source, and rock phosphate ore, but permits water and soluble phosphate to diffuse into the soil. A method of using the composition for providing phosphate fertilizer to plants is also disclosed. 13 figs.

  19. Screw-released roller brake

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1999-01-01

    A screw-released roller brake including an input drive assembly, an output drive assembly, a plurality of locking sprags, a mechanical tripper nut for unlocking the sprags, and a casing therefor. The sprags consist of three dimensional (3-D) sprag members having pairs of contact surface regions which engage respective pairs of contact surface regions included in angular grooves or slots formed in the casing and the output drive assembly. The sprags operate to lock the output drive assembly to the casing to prevent rotation thereof in an idle mode of operation. In a drive mode of operation, the tripper is either self actuated or motor driven and is translated linearly up and down against a spline and at the limit of its travel rotates the sprags which unlock while coupling the input drive assembly to the output drive assembly so as to impart a turning motion thereto in either a clockwise or counterclockwise direction.

  20. Gas release in comet nuclei

    NASA Technical Reports Server (NTRS)

    Prialnik, Dina; Bar-Nun, Akiva

    1990-01-01

    Processes taking place during the evolution of a comet nucleus are examined, taking into account the release of gas on crystallization and the gas flow through the porous nucleus. In particular, the stresses caused by the gas pressure, the contribution of gas flow to the heat transfer, and the rate of gas emission by the comet along its orbit were determined using a model of spherically symmetric comet nucleus made of porous amorphous ice, with 10 percent CO gas trapped in it. Several values of density and pore size are considered, and for each combination of parameters, the model is evolved for 20-30 revolutions in Comet P/Halley's orbit. It is shown that a model of 0.2 g/cu cm density reproduces well many of the light-curve and activity characteristics of Comet P/Halley.

  1. Biomediated continuous release phosphate fertilizer

    SciTech Connect

    Goldstein, Alan H.; Rogers, Robert D.

    1999-01-01

    A composition is disclosed for providing phosphate fertilizer to the root zone of plants. The composition comprises a microorganism capable of producing and secreting a solubilization agent, a carbon source for providing raw material for the microorganism to convert into the solubilization agent, and rock phosphate ore for providing a source of insoluble phosphate that is solubilized by the solubilization agent and released as soluble phosphate. The composition is provided in a physical form, such as a granule, that retains the microorganism, carbon source, and rock phosphate ore, but permits water and soluble phosphate to diffuse into the soil. A method of using the composition for providing phosphate fertilizer to plants is also disclosed.

  2. Chemical releases in the ionosphere

    NASA Technical Reports Server (NTRS)

    Davis, T. N.

    1979-01-01

    The study of the interaction between the atmosphere, ionosphere and magnetosphere is identified as a major task worthy of pursuit. The present review demonstrates the major contributions to this complex problem already made by active experiments involving the injection of chemicals and energetic electron beams into the atmosphere, ionosphere and magnetosphere. Through the use of chemical releases, it has been possible to investigate a number of quantities including high-altitude winds and electric fields, the detailed configurations of the geomagnetic field within the ionosphere and the magnetosphere, as well as the propagation of energetic particle beams and their interaction with natural neutral and ionized constituents of the high atmosphere. So far, virtually all of this effort has been accomplished using rockets. In the future, it is obvious that satellite platforms will play a greater role, both in making injections and in observing their effects.

  3. Dose Comparison And Side Effect Profile Of Metformin Extended Release Versus Metformin Immediate Release.

    PubMed

    Hameed, Maliha; Khan, Khurshid; Salman, Sadia; Mehmood, Nasir

    2017-01-01

    Diabetes Mellitus type 2 is very common worldwide, with majority of cases in Asia Pacific region. Metformin is the first line therapy, along with lifestyle modification for all type 2 diabetics as recommended by ADA. Metformin is available as conventional Metformin Immediate Release (MIR) and Metformin Extended Release (MXR). Metformin XR has better gastrointestinal tolerability and fewer side effects as compared to Metformin IR, with similar efficacy regarding anti-hyperglycaemic effects. The objective of this study was to determine whether metformin XR is as effective as Metformin IR in maintaining glycaemic control at equivalent doses or even at reduced doses; and to compare the side effect profile of the two preparations. This randomized control trial was conducted at Medical and Endocrinology OPD of Jinnah Hospital Lahore. A total of 90 type 2 diabetics of both genders were recruited using nonprobability purposive sampling. Patients were randomized into 3 groups; 30 in each group. Group 1 received Metformin IR 1000 mg twice daily; group 2 received metformin XR 1000 mg twice daily; and group 3 received metformin XR 500 mg twice daily, for a period of three months. HbA1c was done at baseline and after three months of therapy along with fasting blood sugars and random blood sugars weekly. The mean age of patients was 46±9 years, with 54% being males and 46% being females. There was a 1% reduction in HbA1c in group 1, 0.7% reduction in group 2 and only 0.4% reduction in group 3. Similarly, all three therapies were equally effective in reducing blood sugar fasting and blood sugar random at three months. Side effects namely diarrhoea, dyspepsia and flatulence were greatest with Metformin IR (40%) but less than half with Metformin XR at equivalent dose and negligible at half the dose. All three Metformin groups were effective in reduction of HbA1C and glycaemic control clinically and there is no statistical difference in HbA1c reduction among groups at three months.

  4. Effects of cannabinoids on adrenaline release from adrenal medullary cells

    PubMed Central

    Niederhoffer, Nathalie; Hansen, Henrik H; Fernandez-Ruiz, Javier J; Szabo, Bela

    2001-01-01

    The objective of the present study was to analyse the peripheral effects of cannabinoids on adrenaline release from adrenal chromaffin cells. In pithed rabbits with electrically stimulated sympathetic outflow, intravenous injection of the cannabinoid receptor agonists WIN55212-2 and CP55940 (5, 50 and 500 μg kg−1) markedly lowered the plasma adrenaline concentration. The effect of WIN55212-2 was attenuated by the selective CB1 cannabinoid receptor antagonist SR141716A (500 μg kg−1). WIN55212-3 (same doses as WIN55212-2), the enantiomer of WIN55212-2 lacking affinity for cannabinoid receptors, had no effect on the plasma adrenaline concentration. In rabbit isolated adrenal glands, the release of adrenaline elicited by electrical stimulation was measured by fast cyclic voltammetry. Electrically-evoked adrenaline release was inhibited by WIN55212-2 (0.3, 1, 3 and 10 μM) and this effect was antagonized by SR141716A (1 μM). The non-cholinergic component of adrenaline release observed after blockade of nicotinic (by hexamethonium 100 μM) and muscarinic (by atropine 0.5 μM) acetylcholine receptors was not depressed by WIN55212-2. WIN55212-3 (10 μM) had no effect on adrenaline release. No detectable specific CB1 receptor binding and mRNA expression were found in rabbit adrenal glands with autoradiography and in situ hybridization. The results show that cannabinoids inhibit adrenaline secretion in rabbit isolated adrenal glands; the likely mechanism is a presynaptic CB1 receptor-mediated inhibition of acetylcholine release from preganglionic sympathetic neurons. The inhibition of adrenaline secretion in adrenal glands most probably accounts for the decrease in the plasma adrenaline concentration observed after cannabinoid administration in pithed rabbits. PMID:11704653

  5. Release Data Package for Hanford Site Assessments

    SciTech Connect

    Riley, Robert G.; Lopresti, Charles A.; Engel, David W.

    2006-07-01

    Beginning in fiscal year (FY) 2003, the U.S. Department of Energy (DOE) Richland Operations Office initiated activities, including the development of data packages, to support a Hanford assessment. This report describes the data compiled in FY 2003 through 2005 to support the Release Module of the System Assessment Capability (SAC) for the updated composite analysis. This work was completed as part of the Characterization of Systems Project, part of the Remediation and Closure Science Project, the Hanford Assessments Project, and the Characterization of Systems Project managed by Pacific Northwest National Laboratory. Related characterization activities and data packages for the vadose zone and groundwater are being developed under the remediation Decision Support Task of the Groundwater Remediation Project managed by Fluor Hanford, Inc. The Release Module applies release models to waste inventory data from the Inventory Module and accounts for site remediation activities as a function of time. The resulting releases to the vadose zone, expressed as time profiles of annual rates, become source terms for the Vadose Zone Module. Radioactive decay is accounted for in all inputs and outputs of the Release Module. The Release Module is implemented as the VADER (Vadose zone Environmental Release) computer code. Key components of the Release Module are numerical models (i.e., liquid, soil-debris, cement, saltcake, and reactor block) that simulate contaminant release from the different waste source types found at the Hanford Site. The Release Module also handles remediation transfers to onsite and offsite repositories.

  6. A-1 Test Stand work

    NASA Image and Video Library

    2010-01-13

    Employees at NASA's John C. Stennis Space Center work to maneuver a structural steam beam into place on the A-1 Test Stand on Jan. 13. The beam was one of several needed to form the thrust takeout structure that will support a new thrust measurement system being installed on the stand for future rocket engine testing. Once lifted onto the stand, the beams had to be hoisted into place through the center of the test stand, with only two inches of clearance on each side. The new thrust measurement system represents a state-of-the-art upgrade from the equipment installed more than 40 years ago when the test stand was first constructed.

  7. Lithium stimulates the release of human parathyroid hormone in vitro.

    PubMed

    Birnbaum, J; Klandorf, H; Giuliano, A; Van Herle, A

    1988-06-01

    The effect of lithium on PTH release from human parathyroid tissue was studied using a perifusion system and an immunoradiometric assay for intact human PTH. Tissue was obtained from three patients undergoing surgery for thyroid disease, three patients with secondary hyperparathyroidism due to chronic renal insufficiency, and four patients with primary hyperparathyroidism due to a parathyroid adenoma. Addition of lithium in concentrations equivalent to the therapeutic serum levels normally attained in man (1.3 mmol/L) resulted in a significant (P less than 0.05) increase in PTH release under normocalcemic (1.15 mmol/L) conditions from normal and hyperplastic tissues. The magnitude of the lithium-induced response of PTH release ranged from a 1.4- to 5.3-fold increase above basal levels (perifusion with 1.15 mmol/L calcium alone) and was comparable to the response during a low calcium (0.42 mmol/L) perifusion. Although the response to lithium was delayed compared to that of hypocalcemia, PTH returned to basal levels immediately after removal of either stimulator. In contrast, parathyroid adenomas did not respond to either lithium or hypocalcemia in a characteristic manner, but, rather, functioned in an autonomous fashion with repeated pulsatile bursts of PTH release that were not suppressible even under hypercalcemic (1.70 mmol/L) conditions. These in vitro studies suggest that lithium therapy may elevate serum PTH levels in some patients and could, thus, be responsible for hypercalcemia in them.

  8. Effects of artemisinin sustained-release granules on mixed alga growth and microcystins production and release.

    PubMed

    Ni, Lixiao; Li, Danye; Hu, Shuzhen; Wang, Peifang; Li, Shiyin; Li, Yiping; Li, Yong; Acharya, Kumud

    2015-12-01

    To safely and effectively apply artemisinin sustained-release granules to control and prevent algal water-blooms, the effects of artemisinin and its sustained-release granules on freshwater alga (Scenedesmus obliquus (S. obliquus) and Microcystis aeruginosa (M. aeruginosa)), as well as the production and release of microcystins (MCs) were studied. The results showed that artemisinin sustained-release granules inhibited the growth of M. aeruginosa (above 95% IR) and S. obliquus (about 90% IR), with M. aeruginosa more sensitive. The artemisinin sustained-release granules had a longer inhibition effect on growth of pure algae and algal coexistence than direct artemisinin dosing. The artemisinin sustained-release granules could decrease the production and release of algal toxins due to the continued stress of artemisinin released from artemisinin sustained-release granules. There was no increase in the total amount of MC-LR in the algal cell culture medium.

  9. The Effect of Ethanol on the Release of Opioids from Oral Prolonged-Release Preparations

    PubMed Central

    Walden, Malcolm; Nicholls, Fiona A.; Smith, Kevin J.; Tucker, Geoffrey T.

    2007-01-01

    Recent experience has prompted the US FDA to consider whether ethanol ingestion may modify the release characteristics of prolonged-release formulations, where dose dumping may be an issue for patient safety. The influence of ethanol on the in vitro release of opioid drugs from some prolonged-release formulations utilizing different release technologies was examined. Results indicated that the prolonged-release mechanisms remained intact under the testing conditions, although one product showed initial sensitivity to ethanol in its release characteristics. Nevertheless, in this case, extrapolation of the findings to likely outcome in vivo indicated no risk of dose-dumping. It is proposed that prolonged-release medicinal products should be tested during development to ensure robustness to the effects of ethanol on drug release. PMID:17882730

  10. Model for TCLP Releases from Waste Glasses

    SciTech Connect

    Kim, Dong-Sang; Vienna, John D.

    2003-05-01

    A first-order property model for normalized Toxicity Characteristic Leaching Procedure (TCLP) release as a function of glass composition was developed using data collected from various studies. The normalized boron release is used to estimate the release of toxic elements based on the observation that the boron release represents the conservative release for those constituents of interest. The current TCLP model has two targeted application areas: (1) delisting of waste-glass product as radioactive (not mixed) waste and (2) designating the glass wastes generated from waste-glass research activities as hazardous or non-hazardous. This report describes the data collection and model development for TCLP releases and discusses the issues related to the application of the model.

  11. Helium release during shale deformation: Experimental validation

    NASA Astrophysics Data System (ADS)

    Bauer, Stephen J.; Gardner, W. Payton; Heath, Jason E.

    2016-07-01

    This work describes initial experimental results of helium tracer release monitoring during deformation of shale. Naturally occurring radiogenic 4He is present in high concentration in most shales. During rock deformation, accumulated helium could be released as fractures are created and new transport pathways are created. We present the results of an experimental study in which confined reservoir shale samples, cored parallel and perpendicular to bedding, which were initially saturated with helium to simulate reservoir conditions, are subjected to triaxial compressive deformation. During the deformation experiment, differential stress, axial, and radial strains are systematically tracked. Release of helium is dynamically measured using a helium mass spectrometer leak detector. Helium released during deformation is observable at the laboratory scale and the release is tightly coupled to the shale deformation. These first measurements of dynamic helium release from rocks undergoing deformation show that helium provides information on the evolution of microstructure as a function of changes in stress and strain.

  12. Double-Swivel Mechanism For Reliable Release

    NASA Technical Reports Server (NTRS)

    King, Guy L.; Schneider, William C.

    1990-01-01

    Double-swivel toggle mechanism releases large, heavy objects reliably. Double-swiveling action of mechanism ensures it clears restraining pins upon release. Pins retain toggle and its load. If pin fails to withdraw at designated time for releasing payload, toggle swivels about its upper ball, and ring swivels about lower ball so ring flange clears failed pin. Double-swivel action ensures disengagement even it two pins fail to withdraw.

  13. GROA AIRBORNE RELEASE DISPERSION FACTOR CALCULATION

    SciTech Connect

    J. Wang

    2005-03-21

    The purpose of this document is to calculate airborne release dispersion factors ({chi}/Q) for the surface and subsurface facilities at the Geological Repository Operations Area (GROA). The calculated {chi}/Q values may be used to estimate radiological consequences to workers for potential releases from normal operations and event sequences for License Application. The scope of this document is to provide estimates of {chi}/Q values at potential onsite receptors from facility releases, under normal operating conditions and event sequences.

  14. Environmental releases for calendar year 1996

    SciTech Connect

    Greager, E.M.

    1997-07-31

    This report presents data on radioactive and nonradioactive materials released into the environment during calendar year 1996 from facilities and activities managed by the Fluor Daniel Hanford, Incorporated (formerly the Westinghouse Hanford Company) and Bechtel Hanford, Incorporated. Fluor Daniel Hanford, Incorporated provides effluent monitoring services for Bechtel Hanford, Incorporated, which includes release reporting. Both summary and detailed presentations of the environmental releases are provided. When appropriate, comparisons to data from previous years are made.

  15. Environmental releases for calendar year 1995

    SciTech Connect

    Diediker, L.P., Westinghouse Hanford

    1996-07-30

    This report presents data on radioactive and nonradioactive materials released into the environment during calendar year 1995 from facilities managed by the Westinghouse Hanford Company (WHC) and monitored by Bechtel Hanford, Incorporated (BHI). WHC provides effluent monitoring services for BHI, which includes release reporting. Both summary and detailed presentations of the environmental releases are provided. When appropriate,comparisons to data from previous years are made.

  16. Somatodendritic dopamine release: recent mechanistic insights

    PubMed Central

    Rice, Margaret E.; Patel, Jyoti C.

    2015-01-01

    Dopamine (DA) is a key transmitter in motor, reward and cogitative pathways, with DA dysfunction implicated in disorders including Parkinson's disease and addiction. Located in midbrain, DA neurons of the substantia nigra pars compacta project via the medial forebrain bundle to the dorsal striatum (caudate putamen), and DA neurons in the adjacent ventral tegmental area project to the ventral striatum (nucleus accumbens) and prefrontal cortex. In addition to classical vesicular release from axons, midbrain DA neurons exhibit DA release from their cell bodies and dendrites. Somatodendritic DA release leads to activation of D2 DA autoreceptors on DA neurons that inhibit their firing via G-protein-coupled inwardly rectifying K+ channels. This helps determine patterns of DA signalling at distant axonal release sites. Somatodendritically released DA also acts via volume transmission to extrasynaptic receptors that modulate local transmitter release and neuronal activity in the midbrain. Thus, somatodendritic release is a pivotal intrinsic feature of DA neurons that must be well defined in order to fully understand the physiology and pathophysiology of DA pathways. Here, we review recent mechanistic aspects of somatodendritic DA release, with particular emphasis on the Ca2+ dependence of release and the potential role of exocytotic proteins. PMID:26009764

  17. Arthroscopic Capsular Release of the Talocalcaneonavicular Joint.

    PubMed

    Lui, Tun Hing

    2016-12-01

    Arthrofibrosis of the talocalcaneonavicular joint can follow talar neck fracture especially if anterior approaches have been used for fracture fixation. Capsular release of the talocalcaneonavicular joint is indicated if the painful hindfoot stiffness cannot be controlled with conservative treatment. Open capsular release of the talocalcaneonavicular joint demands extensive soft tissue dissection and hinders early postoperative mobilization exercise of the joint. The purpose of this technical note is to describe a minimally invasive approach of arthroscopic capsular release of the talocalcaneonavicular joint that is composed of arthroscopic release of the talonavicular joint and the anterior subtalar joint. This allows immediate postoperative mobilization of the joint.

  18. Quick-release medical tape

    PubMed Central

    Laulicht, Bryan; Langer, Robert; Karp, Jeffrey M.

    2012-01-01

    Medical tape that provides secure fixation of life-sustaining and -monitoring devices with quick, easy, damage-free removal represents a longstanding unmet medical need in neonatal care. During removal of current medical tapes, crack propagation occurs at the adhesive–skin interface, which is also the interface responsible for device fixation. By designing quick-release medical tape to undergo crack propagation between the backing and adhesive layers, we decouple removal and device fixation, enabling dual functionality. We created an ordered adhesive/antiadhesive composite intermediary layer between the medical tape backing and adhesive for which we achieve tunable peel removal force, while maintaining high shear adhesion to secure medical devices. We elucidate the relationship between the spatial ordering of adhesive and antiadhesive regions to create a fully tunable system that achieves strong device fixation and quick, easy, damage-free device removal. We also described ways of neutralizing the residual adhesive on the skin and have observed that thick continuous films of adhesive are easier to remove than the thin islands associated with residual adhesive left by current medical tapes. PMID:23112196

  19. Thyroid hormone biosynthesis and release.

    PubMed

    Carvalho, Denise P; Dupuy, Corinne

    2017-01-31

    Thyroid hormones (TH) 3,5,3',5'- tetraiodothyronine or thyroxine (T4) and 3,5,3'- triiodothyronine (T3) contain iodine atoms as part of their structure, and their synthesis occur in the unique structures called thyroid follicles. Iodide reaches thyroid cells through the bloodstream that supplies the basolateral plasma membrane of thyrocytes, where it is avidly taken up through the sodium/iodide symporter (NIS). Thyrocytes are also specialized in the secretion of the high molecular weight protein thyroglobulin (TG) in the follicular lumen. The iodination of the tyrosyl residues of TG preceeds TH biosynthesis, which depends on the interaction of iodide, TG, hydrogen peroxide (H2O2) and thyroid peroxidase (TPO) at the apical plasma membrane of thyrocytes. Thyroid hormone biosynthesis is under the tonic control of thyrotropin (TSH), while the iodide recycling ability is very important for normal thyroid function. We discuss herein the biochemical aspects of TH biosynthesis and release, highlighting the novel molecules involved in the process.

  20. Quick-release connector module

    NASA Technical Reports Server (NTRS)

    Sedig, Albert R. (Inventor)

    1995-01-01

    A multi-bay electrical connector is described, of the type that has a frame (12, FIG. 2 ) with cavities (14) that each holds a separate module 20, which enables quick withdrawal of a single module from the frame and its quick replacement. A lock arm (42) is slidable along a first side (50) of a first cavity, and has at least one lock lug (80). A first module has a barrier part (70) that lies inward of the lock lug, which prevents outward movement of the first module out of the frame cavity. The lock arm can be moved to an unlocked position wherein the barrier part on the module lies inward of a gap (84) in the lock arm to permit the module to be pulled out of the frame cavity and later inserted therein. A latch (54) is slidable on the frame in directions (A, B) perpendicular to the sliding movement of the lock arm, and has an abutment (112, FIG. 5 ) that abuts a shoulder (114) on the lock arm to keep the lock arm in its unlocked position until the latch is released.

  1. Quick-release medical tape.

    PubMed

    Laulicht, Bryan; Langer, Robert; Karp, Jeffrey M

    2012-11-13

    Medical tape that provides secure fixation of life-sustaining and -monitoring devices with quick, easy, damage-free removal represents a longstanding unmet medical need in neonatal care. During removal of current medical tapes, crack propagation occurs at the adhesive-skin interface, which is also the interface responsible for device fixation. By designing quick-release medical tape to undergo crack propagation between the backing and adhesive layers, we decouple removal and device fixation, enabling dual functionality. We created an ordered adhesive/antiadhesive composite intermediary layer between the medical tape backing and adhesive for which we achieve tunable peel removal force, while maintaining high shear adhesion to secure medical devices. We elucidate the relationship between the spatial ordering of adhesive and antiadhesive regions to create a fully tunable system that achieves strong device fixation and quick, easy, damage-free device removal. We also described ways of neutralizing the residual adhesive on the skin and have observed that thick continuous films of adhesive are easier to remove than the thin islands associated with residual adhesive left by current medical tapes.

  2. 28 CFR 571.22 - Release clothing and transportation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Release clothing and transportation. 571... AND RELEASE RELEASE FROM CUSTODY Release Gratuities, Transportation, and Clothing § 571.22 Release clothing and transportation. (a) Staff shall provide release clothing appropriate for the time of year and...

  3. 28 CFR 571.22 - Release clothing and transportation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Release clothing and transportation. 571... AND RELEASE RELEASE FROM CUSTODY Release Gratuities, Transportation, and Clothing § 571.22 Release clothing and transportation. (a) Staff shall provide release clothing appropriate for the time of year and...

  4. 28 CFR 571.22 - Release clothing and transportation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Release clothing and transportation. 571... AND RELEASE RELEASE FROM CUSTODY Release Gratuities, Transportation, and Clothing § 571.22 Release clothing and transportation. (a) Staff shall provide release clothing appropriate for the time of year and...

  5. Ten Ways to Get Attention with Your Press Releases.

    ERIC Educational Resources Information Center

    Van Kooten, Valerie

    1994-01-01

    Recommends 10 steps that can increase chances of having press release published. Advises readers to use required format; determine what constitutes news; keep release short; include contact person in release; incorporate good quotes; send releases to right person; understand that release will be edited; time arrival of release; follow up with…

  6. 28 CFR 571.22 - Release clothing and transportation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Release clothing and transportation. 571... AND RELEASE RELEASE FROM CUSTODY Release Gratuities, Transportation, and Clothing § 571.22 Release clothing and transportation. (a) Staff shall provide release clothing appropriate for the time of year and...

  7. 28 CFR 571.22 - Release clothing and transportation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Release clothing and transportation. 571... AND RELEASE RELEASE FROM CUSTODY Release Gratuities, Transportation, and Clothing § 571.22 Release clothing and transportation. (a) Staff shall provide release clothing appropriate for the time of year and...

  8. Effect of opioid peptides on electrically evoked acetylcholine release from Torpedo electromotor neurons.

    PubMed

    Oron, L; Sarne, Y; Michaelson, D M

    1991-04-29

    The opioid peptide dynorphin A(1-8) (1 micron) increased acetylcholine release from the Torpedo electric organ by approximately twofold. This effect was reversed by the opiate antagonist naloxone. The effect of Dyn A(1-8) on acetylcholine release was found to vary in magnitude with the seasons of the year, with maximal enhancement being observed in the summer and none in winter. Dynorphin B, methionine-enkephalin and leucine-enkephalin also increased acetylcholine release and showed similar seasonal variations. These findings suggest that acetylcholine release from Torpedo electromotor neurons is regulated by opiate receptors. The physiological significance of these observations is discussed in view of the previous findings that the Torpedo neurons contain an endogenous enkephalin-like peptide.

  9. Prospects for isomeric energy release

    NASA Astrophysics Data System (ADS)

    Karamian, S. A.

    2008-07-01

    The state of experimental studies and promising proposals for the application of nuclear isomers presented as controlled energy or γ-ray sources are reviewed. The properties of isomeric states, methods of their production, and approaches to their efficient stimulation using various types of radiation are analyzed. The long-lived isomers, which can be accumulated in reactor irradiations or in other nuclear interactions with abundant yield, are listed. The isomers are estimated according to their specific energy accumulated per nucleus and the level of the cross section for their formation in reactions with neutrons. The nuclei are classified as promising either for obtaining controlled γ-ray pulses, for the enhanced release of the radioactive decay energy, or for experimental studies on detecting forbidden electromagnetic transitions from the ground to isomeric state. In all cases, the possibility of external-stimulus action on nuclear transitions has key significance, which should become the subject of investigations. The results of successful observation of stimulation of isomers are described at excitation energy E* > 1 MeV in the reactions with bremsstrahlung photons and Coulomb excitation in the ion beam. The essential increase in the K-hindered transitions with increasing energy and also the K-mixing at high rotational frequency for high-spin levels are discussed. The attention is focused on attempts to detect the triggering induced by the radiation in the x-ray range, in particular, that of the 178 m2Hf isomer with the help of x-ray sources and the synchrotron radiation. Proposals for experiments with other isomers are considered. The possibility of affecting the nuclear states by means of ionization of electron shells of a corresponding atom is discussed as promising, and various schemes of similar experiments are proposed. The atomic cross sections are eight orders of magnitude higher than the nuclear ones; therefore, the stimulation of an isomer can

  10. Niacin extended-release/simvastatin.

    PubMed

    Sanford, Mark; Curran, Monique P

    2008-01-01

    Niacin extended-release (ER)/simvastatin is a once-daily, fixed-dose combination of the HMG-CoA reductase inhibitor simvastatin and an ER formulation of niacin (a B-complex vitamin). In healthy volunteers who were given niacin ER/simvastatin 2000 mg/40 mg, niacin exposure was similar to that with niacin ER 2000 mg, while simvastatin exposure was increased compared to that with simvastatin 40 mg. In patients with elevated non-high-density lipoprotein cholesterol (non-HDL-C) but with low-density lipoprotein cholesterol (LDL-C) at or below the National Cholesterol Education Program (NCEP) goal after a > or = 2-week simvastatin 20 mg/day run-in period (SEACOAST I), 24 weeks of niacin ER/simvastatin 1000 mg/20 mg or 2000 mg/20 mg per day reduced median plasma non-HDL-C levels to a significantly greater extent than simvastatin 20 mg/day. In patients with elevated non-HDL-C and LDL-C at any level after a > or = 2-week simvastatin 40 mg/day run-in period (SEACOAST II), 24 weeks of niacin ER/simvastatin 1000 mg/40 mg or 2000 mg/40 mg per day was noninferior to simvastatin 80 mg/day in reducing median plasma non-HDL-C levels. Compared with simvastatin monotherapy, there was no significant difference in reduction in plasma LDL-C levels with niacin ER/simvastatin in SEACOAST I, and the noninferiority criterion for LDL-C was not met in SEACOAST II. However, plasma HDL-C levels increased more and triglyceride levels were lowered more than with simvastatin monotherapy (SEACOAST I and II). Niacin ER/simvastatin was generally well tolerated, with flushing being the most common adverse reaction.

  11. Ignition and flame characteristics of cryogenic hydrogen releases

    DOE PAGES

    Panda, Pratikash P.; Hecht, Ethan S.

    2017-01-01

    In this work, under-expanded cryogenic hydrogen jets were investigated experimentally for their ignition and flame characteristics. The test facility described herein, was designed and constructed to release hydrogen at a constant temperature and pressure, to study the dispersion and thermo-physical properties of cryogenic hydrogen releases and flames. In this study, a non-intrusive laser spark focused on the jet axis was used to measure the maximum ignition distance. The radiative power emitted by the corresponding jet flames was also measured for a range of release scenarios from 37 K to 295 K, 2–6 barabs through nozzles with diameters from 0.75 tomore » 1.25 mm. The maximum ignition distance scales linearly with the effective jet diameter (which scales as the square root of the stagnant fluid density). A 1-dimensional (stream-wise) cryogenic hydrogen release model developed previously at Sandia National Laboratories (although this model is not yet validated for cryogenic hydrogen) was exercised to predict that the mean mole fraction at the maximum ignition distance is approximately 0.14, and is not dependent on the release conditions. The flame length and width were extracted from visible and infra-red flame images for several test cases. The flame length and width both scale as the square root of jet exit Reynolds number, as reported in the literature for flames from atmospheric temperature hydrogen. As shown in previous studies for ignited atmospheric temperature hydrogen, the radiative power from the jet flames of cold hydrogen scales as a logarithmic function of the global flame residence time. The radiative heat flux from jet flames of cold hydrogen is higher than the jet flames of atmospheric temperature hydrogen, for a given mass flow rate, due to the lower choked flow velocity of low-temperature hydrogen. Lastly, this study provides critical information with regard to the development of models to inform the safety codes and standards of hydrogen

  12. Ignition and flame characteristics of cryogenic hydrogen releases

    SciTech Connect

    Panda, Pratikash P.; Hecht, Ethan S.

    2017-01-01

    In this work, under-expanded cryogenic hydrogen jets were investigated experimentally for their ignition and flame characteristics. The test facility described herein, was designed and constructed to release hydrogen at a constant temperature and pressure, to study the dispersion and thermo-physical properties of cryogenic hydrogen releases and flames. In this study, a non-intrusive laser spark focused on the jet axis was used to measure the maximum ignition distance. The radiative power emitted by the corresponding jet flames was also measured for a range of release scenarios from 37 K to 295 K, 2–6 barabs through nozzles with diameters from 0.75 to 1.25 mm. The maximum ignition distance scales linearly with the effective jet diameter (which scales as the square root of the stagnant fluid density). A 1-dimensional (stream-wise) cryogenic hydrogen release model developed previously at Sandia National Laboratories (although this model is not yet validated for cryogenic hydrogen) was exercised to predict that the mean mole fraction at the maximum ignition distance is approximately 0.14, and is not dependent on the release conditions. The flame length and width were extracted from visible and infra-red flame images for several test cases. The flame length and width both scale as the square root of jet exit Reynolds number, as reported in the literature for flames from atmospheric temperature hydrogen. As shown in previous studies for ignited atmospheric temperature hydrogen, the radiative power from the jet flames of cold hydrogen scales as a logarithmic function of the global flame residence time. The radiative heat flux from jet flames of cold hydrogen is higher than the jet flames of atmospheric temperature hydrogen, for a given mass flow rate, due to the lower choked flow velocity of low-temperature hydrogen. Lastly, this study provides critical information with regard to the development of models to inform the safety codes and standards of hydrogen

  13. Application of curdlan to controlled drug delivery. III. Drug release from sustained release suppositories in vitro.

    PubMed

    Kanke, M; Tanabe, E; Katayama, H; Koda, Y; Yoshitomi, H

    1995-08-01

    The use of curdlan, a natural beta-1,3-glucan, in the preparation of sustained release suppositories was studied in vitro. To prepare the suppositories, indomethacin, prednisolone or salbutamol sulfate was mixed with curdlan gel. Preparation conditions, including heating time and curdlan concentrations of 5 and 10%, had little effect on the drug release. The tonicity (hypotonic or isotonic) of the media for the suppository preparation and for in vitro drug release study also had little effect on drug release. However, the heating temperature during gel preparation, the drug amount in the suppository and the type of release media did affect drug release. It was found that drug release was sustained and diffusion-controlled in the three drugs. And finally, curdlan can be applicable for use in a sustained release suppository.

  14. 77 FR 1976 - Release of Waybill Data

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-12

    ... Surface Transportation Board Release of Waybill Data AGENCY: Surface Transportation Board, DOT. ACTION: Release of Waybill Data; Correction. SUMMARY: This document corrects a notice appearing in the Federal... of Trinity Industries, Inc. (WB605-8-12/20/11) for permission to use certain data from the Board's...

  15. 45 CFR 35.8 - Release.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 45 Public Welfare 1 2011-10-01 2011-10-01 false Release. 35.8 Section 35.8 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION TORT CLAIMS AGAINST THE GOVERNMENT Procedures § 35.8 Release. Acceptance by the claimant, his agent or legal representative, of any award, compromise...

  16. 34 CFR 35.8 - Release.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 1 2010-07-01 2010-07-01 false Release. 35.8 Section 35.8 Education Office of the Secretary, Department of Education TORT CLAIMS AGAINST THE GOVERNMENT Procedures § 35.8 Release. Acceptance by the claimant, his agent or legal representative, of any award, compromise or settlement made...

  17. 19 CFR 142.48 - Release procedure.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... manufacturer code, the quantity and unit of measure, the release site, the HTSUS number(s), the C-4 Code and... entry number, the date and time of release, the inspector's badge number, the quantity and unit of measure, and the C-4 Code will be printed on the invoice and the manifest document and, when other agency...

  18. Extended-release methylphenidate (Ritalin LA).

    PubMed

    Lyseng-Williamson, Katherine A; Keating, Gillian M

    2002-01-01

    An extended-release formulation of methylphenidate (Ritalin LA), a CNS stimulant that inhibits dopamine and noradrenaline (norepinephrine) reuptake into presynaptic neurons, has been developed for use in patients with attention deficit/hyperactivity disorder (ADHD). In children with ADHD and healthy male adults, extended-release methylphenidate 20mg was rapidly absorbed and demonstrated two distinct peak plasma concentrations approximately 4 hours apart. The absorption pharmacokinetics of extended-release methylphenidate 20mg, which closely mimics those of immediate-release methylphenidate 10mg given in two doses 4 hours apart, permits once-daily administration. In a 2-week randomised, double-blind, placebo-controlled trial in 134 evaluable children aged 6 to 12 years with ADHD, symptoms improved to a significantly greater extent with extended-release methylphenidate 10 to 40mg once daily than with placebo. Extended-release methylphenidate improved both inattention and hyperactivity symptoms and was effective in children with combined- (inattentive and hyperactive/impulsive) type or predominantly inattentive-type ADHD. In clinical trials, the safety and tolerability profiles of extended-release methylphenidate were consistent with that of the immediate-release formulation.

  19. 27 CFR 27.185 - Customs release.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Customs release. 27.185... Distilled Spirits From Customs Custody Free of Tax for Use of the United States § 27.185 Customs release. (a) Upon receipt of appropriate customs entry and a photocopy of a permit, Form 5150.33 or...

  20. Releasable Asbestos Field Sampler (RAFS) Operation Manual

    EPA Science Inventory

    The Releasable Asbestos Field Sampler (RAFS) is a field instrument that provides an in-situ measurement of asbestos releasability from consistent and reproducible mechanical agitation of the source material such as soil. The RAFS was designed to measure concentration (asbestos st...

  1. 40 CFR 302.8 - Continuous releases.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... release data, engineering estimates, knowledge of operating procedures, or best professional judgment to...) The environmental medium(a) affected by the release: (1) If surface water, the name of the surface... use; (3) If a lake, the surface area (in acres) and average depth (in feet or meters); (4) If on or...

  2. 40 CFR 302.8 - Continuous releases.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... stack, the stack height (in feet or meters). (D) The frequency of the release and the fraction of the... use; (3) If a lake, the surface area (in acres) and average depth (in feet or meters); (4) If on or... stack, the stack height (in feet or meters). (iv) The frequency of the release and the fraction of...

  3. Shape-Memory-Alloy Release Mechanism

    NASA Technical Reports Server (NTRS)

    Mckinnis, Darin

    1993-01-01

    Release-nut mechanism activated by electric current applied to shape-memory alloy. Separates attached objects quickly by remote control. Does not create hazard or cause damage. Shape-memory release-nut mechanism unaffected by moisture or vacuum. Requires sustained current lasting 5 seconds or longer, and insensitive to electromagnetic interference. Mechanism can be reused.

  4. Extracellular proton release by stimulated neutrophils

    SciTech Connect

    van Zwieten, R.; Wever, R.; Hamers, M.N.; Weening, R.S.; Roos, D.

    1981-07-01

    We have tried to elucidate the mechanism of phagosome acidification in human neutrophils. Assuming that phenomena occurring at the plasma membrane reflect reactions in the phagocytic vacuoles, we have stimulated human neutrophils with agents that induce a ''respiratory burst,'' and we have measured the release of protons into the extracellular medium. Phorbol myristate acetate, N-formyl-methionyl-leucyl-phenylalanine and serum-opsonized zymosan particles each caused a rapid release of protons, concomitant with the increase in oxygen consumption. The stimulated release of protons was strictly coupled to the increase respiration of the cells, because inhibition of the respiration of either anaerobiosis, chlorpromazine, or glycolytic inhibitors also inhibited the release of protons. Also, in the presence of the above-mentioned stimulating agents, neutrophils from three patients with chronic granulomatous disease enhanced neither respiration not proton release. In normal cells, the ratio of deltaH+/-deltaO2 was 1.04 +/- 0.19 (mean +/ SD, n . 13). The mechanism of this proton release is not clear. The amount of lactic and carbonic acid produced by stimulated neutrophils was inadequate to explain the amount of protons released. Perhydroxyl radicals were also ruled out as the source of the protons. Because the cells did not release measurable amounts of phosphate ions, a phosphate-hydroxyl-ion antiport was also excluded. Finally, the lack of any effect of uncouplers renders it unlikely that a respiration-driven proton gradient is built up across the plasma membrane.

  5. Method for releasing hydrogen from ammonia borane

    SciTech Connect

    Varma, Arvind; Diwan, Moiz; Shafirovich, Evgeny; Hwang, Hyun-Tae; Al-Kukhun, Ahmad

    2013-02-19

    A method of releasing hydrogen from ammonia borane is disclosed. The method comprises heating an aqueous ammonia borane solution to between about 80-135.degree. C. at between about 14.7 and 200 pounds per square inch absolute (psia) to release hydrogen by hydrothermolysis.

  6. 49 CFR 236.790 - Release, time.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Release, time. 236.790 Section 236.790... Release, time. A device used to prevent the operation of an operative unit until after the expiration of a predetermined time interval after the device has been actuated. ...

  7. A Model for Delimited Information Release

    DTIC Science & Technology

    2004-01-01

    A Model for Delimited Information Release Andrei Sabelfeld?1 and Andrew C. Myers2 1 Department of Computer Science, Chalmers University of Technology ...system is given that straightforwardly and provably enforces delimited release. Keywords: Computer security, confidentiality , information flow, nonin...verifiably protect the confidentiality of sensitive information in practical computing systems. One of the most vexing difficulties is that realistic

  8. 49 CFR 236.790 - Release, time.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Release, time. 236.790 Section 236.790... Release, time. A device used to prevent the operation of an operative unit until after the expiration of a predetermined time interval after the device has been actuated. ...

  9. 49 CFR 236.790 - Release, time.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Release, time. 236.790 Section 236.790... Release, time. A device used to prevent the operation of an operative unit until after the expiration of a predetermined time interval after the device has been actuated. ...

  10. Release of Unreviewed Studies Sparks Debate

    ERIC Educational Resources Information Center

    Viadero, Debra

    2005-01-01

    Studies generally undergo an evaluation process before they are accepted for publication in an academic journal, presented at a conference, or released by a think tank. This article discusses the release of unreviewed research that sparks debate over the need for tighter peer-review mechanisms. Researchers from two of the nation's most eminent…

  11. Releasing yellow birch saplings and poles

    Treesearch

    Gayne G. Erdmann; Ralph M., Jr. Peterson

    1992-01-01

    Yellow birch needs moisture, nutrients, overhead light, and enough space for the crown to expand in order to compete successfully with faster-growing northern hardwoods. By releasing crowns early, you can increase the number of future veneer and saw log trees in a stand and double the growth rate, thus cutting rotations in half. If you delay crown release too long,...

  12. Releasable Asbestos Field Sampler (RAFS) Operation Manual

    EPA Science Inventory

    The Releasable Asbestos Field Sampler (RAFS) is a field instrument that provides an in-situ measurement of asbestos releasability from consistent and reproducible mechanical agitation of the source material such as soil. The RAFS was designed to measure concentration (asbestos st...

  13. Fluoride and chlorhexidine release from filled resins.

    PubMed

    Shen, C; Zhang, N-Z; Anusavice, K J

    2010-09-01

    Resin-based materials that release either fluoride or chlorhexidine have been formulated for inhibiting caries activity. It is not known if the two agents, when incorporated into one material, would interact and affect their release potential. We hypothesized that the ratio of fluoride to chlorhexidine incorporated into a resin, and the pH of the storage medium, will affect their releases from the material. The material investigated contained 23 wt% of filler, and the ratios of calcium fluoride to chlorhexidine diacetate were 8/2, 5/5, and 2/8. The release was conducted in pH 4, 5, and 6 acetate buffers. The results showed that release of either agent increased as the pH of the medium decreased. The presence of fluoride salt substantially reduced the chlorhexidine release, while the presence of a specific quantity of chlorhexidine significantly increased fluoride release. This interaction can be utilized to optimize the release of either agent for therapeutic purposes.

  14. Fluoride and Chlorhexidine Release from Filled Resins

    PubMed Central

    Shen, C.; Zhang, N.-Z.; Anusavice, K.J.

    2010-01-01

    Resin-based materials that release either fluoride or chlorhexidine have been formulated for inhibiting caries activity. It is not known if the two agents, when incorporated into one material, would interact and affect their release potential. We hypothesized that the ratio of fluoride to chlorhexidine incorporated into a resin, and the pH of the storage medium, will affect their releases from the material. The material investigated contained 23 wt% of filler, and the ratios of calcium fluoride to chlorhexidine diacetate were 8/2, 5/5, and 2/8. The release was conducted in pH 4, 5, and 6 acetate buffers. The results showed that release of either agent increased as the pH of the medium decreased. The presence of fluoride salt substantially reduced the chlorhexidine release, while the presence of a specific quantity of chlorhexidine significantly increased fluoride release. This interaction can be utilized to optimize the release of either agent for therapeutic purposes. PMID:20581354

  15. A practical guide to oak release.

    Treesearch

    Constance A. Harrington; Warren D. Devine

    2006-01-01

    Oregon white oak savannas and woodlands represent a biological and cultural legacy in the Pacific Northwest. Many Oregon white oak stands are deteriorating owing to invasion and eventual overtopping by Douglas-fir or other conifers. Releasing the shade-intolerant oak trees from overtopping conifers can often restore these oak stands. When planning a release operation,...

  16. Retractions, press releases and newspaper coverage.

    PubMed

    Rada, Roy F

    2007-09-01

    To explore how often newspapers cover the retraction of a medical journal article and whether newspaper coverage corresponds with the appearance of a press release about the retraction. Fifty citations were identified in PubMed that had been indexed with the Medical Subject Heading 'Retracted Publication'. Next, the archives of LexisNexis's 'Major Newspapers' and EurekAlert's press releases were searched to find references to those retracted publications. Newspaper articles addressed exactly three of the 50 retracted publications, and press releases, exactly four of the 50 retracted publications. All three retracted publications that received newspaper coverage also had a press release. In other words, newspapers only covered a retraction that had been introduced by a press release. One would expect that newspaper coverage would increase after a press release, but the suggested relationships among a medical journal article retraction, a press release and newspaper coverage should be further investigated. If the linkage suggested by the data of this study holds, and if newspaper coverage stimulates library patron interest, then a medical library might prepare itself for information requests following a press release.

  17. Teach with Databases: Toxics Release Inventory. [Multimedia].

    ERIC Educational Resources Information Center

    Barracato, Jay; Spooner, Barbara

    This curriculum unit provides students with real world applications of science as it pertains to toxic releases into the environment. This boxed package contains the Toxics Release Inventory (TRI) Teacher's Guide, TRI Database Basics guide, comprehensive TRI compact disk with user's guide, "Getting Started: A Guide to Bringing Environmental…

  18. 7 CFR 356.5 - Bonded release.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Bonded release. 356.5 Section 356.5 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE FORFEITURE PROCEDURES § 356.5 Bonded release. (a) The Deputy Administrator...

  19. Serotonin release varies with brain tryptophan levels

    NASA Technical Reports Server (NTRS)

    Schaechter, Judith D.; Wurtman, Richard J.

    1990-01-01

    This study examines directly the effects on serotonin release of varying brain tryptophan levels within the physiologic range. It also addresses possible interactions between tryptophan availability and the frequency of membrane depolarization in controlling serotonin release. We demonstrate that reducing tryptophan levels in rat hypothalamic slices (by superfusing them with medium supplemented with 100 microM leucine) decreases tissue serotonin levels as well as both the spontaneous and the electrically-evoked serotonin release. Conversely, elevating tissue tryptophan levels (by superfusing slices with medium supplemented with 2 microM tryptophan) increases both the tissue serotonin levels and the serotonin release. Serotonin release was found to be affected independently by the tryptophan availability and the frequency of electrical field-stimulation (1-5 Hz), since increasing both variables produced nearly additive increases in release. These observations demonstrate for the first time that both precursor-dependent elevations and reductions in brain serotonin levels produce proportionate changes in serotonin release, and that the magnitude of the tryptophan effect is unrelated to neuronal firing frequency. The data support the hypothesis that serotonin release is proportionate to intracellular serotonin levels.

  20. 49 CFR 236.790 - Release, time.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Release, time. 236.790 Section 236.790... Release, time. A device used to prevent the operation of an operative unit until after the expiration of a predetermined time interval after the device has been actuated....

  1. Response of Overtopped White Oak to Release

    Treesearch

    Charles E. McGee

    1981-01-01

    Pole sized white oaks increase in volume growth following release from overtopping trees, but the response varies by size, age and appearance of the oaks. Significant increases in epicormic sprouting, height loss by some released trees, and highly variable stem volume growth make overtopped white oak a very questionable source of future crop trees. If overtopped trees...

  2. Extended-release trazodone (Oleptro) for depression.

    PubMed

    2010-11-15

    The FDA has approved the marketing of an extended-release formulation of trazodone (Oleptro--Angelini Labopharm) for treatment of major depressive disorder in adults. Immediate-release trazodone has been available for treatment of depression for many years, but is used mostly in low doses for its sedating effects.

  3. Serotonin release varies with brain tryptophan levels

    NASA Technical Reports Server (NTRS)

    Schaechter, Judith D.; Wurtman, Richard J.

    1990-01-01

    This study examines directly the effects on serotonin release of varying brain tryptophan levels within the physiologic range. It also addresses possible interactions between tryptophan availability and the frequency of membrane depolarization in controlling serotonin release. We demonstrate that reducing tryptophan levels in rat hypothalamic slices (by superfusing them with medium supplemented with 100 microM leucine) decreases tissue serotonin levels as well as both the spontaneous and the electrically-evoked serotonin release. Conversely, elevating tissue tryptophan levels (by superfusing slices with medium supplemented with 2 microM tryptophan) increases both the tissue serotonin levels and the serotonin release. Serotonin release was found to be affected independently by the tryptophan availability and the frequency of electrical field-stimulation (1-5 Hz), since increasing both variables produced nearly additive increases in release. These observations demonstrate for the first time that both precursor-dependent elevations and reductions in brain serotonin levels produce proportionate changes in serotonin release, and that the magnitude of the tryptophan effect is unrelated to neuronal firing frequency. The data support the hypothesis that serotonin release is proportionate to intracellular serotonin levels.

  4. Understanding Drug Release Data through Thermodynamic Analysis

    PubMed Central

    Freire, Marjorie Caroline Liberato Cavalcanti; Alexandrino, Francisco; Marcelino, Henrique Rodrigues; Picciani, Paulo Henrique de Souza; Silva, Kattya Gyselle de Holanda e; Genre, Julieta; de Oliveira, Anselmo Gomes; do Egito, Eryvaldo Sócrates Tabosa

    2017-01-01

    Understanding the factors that can modify the drug release profile of a drug from a Drug-Delivery-System (DDS) is a mandatory step to determine the effectiveness of new therapies. The aim of this study was to assess the Amphotericin-B (AmB) kinetic release profiles from polymeric systems with different compositions and geometries and to correlate these profiles with the thermodynamic parameters through mathematical modeling. Film casting and electrospinning techniques were used to compare behavior of films and fibers, respectively. Release profiles from the DDSs were performed, and the mathematical modeling of the data was carried out. Activation energy, enthalpy, entropy and Gibbs free energy of the drug release process were determined. AmB release profiles showed that the relationship to overcome the enthalpic barrier was PVA-fiber > PVA-film > PLA-fiber > PLA-film. Drug release kinetics from the fibers and the films were better fitted on the Peppas–Sahlin and Higuchi models, respectively. The thermodynamic parameters corroborate these findings, revealing that the AmB release from the evaluated systems was an endothermic and non-spontaneous process. Thermodynamic parameters can be used to explain the drug kinetic release profiles. Such an approach is of utmost importance for DDS containing insoluble compounds, such as AmB, which is associated with an erratic bioavailability. PMID:28773009

  5. Understanding Drug Release Data through Thermodynamic Analysis.

    PubMed

    Freire, Marjorie Caroline Liberato Cavalcanti; Alexandrino, Francisco; Marcelino, Henrique Rodrigues; Picciani, Paulo Henrique de Souza; Silva, Kattya Gyselle de Holanda E; Genre, Julieta; Oliveira, Anselmo Gomes de; Egito, Eryvaldo Sócrates Tabosa do

    2017-06-13

    Understanding the factors that can modify the drug release profile of a drug from a Drug-Delivery-System (DDS) is a mandatory step to determine the effectiveness of new therapies. The aim of this study was to assess the Amphotericin-B (AmB) kinetic release profiles from polymeric systems with different compositions and geometries and to correlate these profiles with the thermodynamic parameters through mathematical modeling. Film casting and electrospinning techniques were used to compare behavior of films and fibers, respectively. Release profiles from the DDSs were performed, and the mathematical modeling of the data was carried out. Activation energy, enthalpy, entropy and Gibbs free energy of the drug release process were determined. AmB release profiles showed that the relationship to overcome the enthalpic barrier was PVA-fiber > PVA-film > PLA-fiber > PLA-film. Drug release kinetics from the fibers and the films were better fitted on the Peppas-Sahlin and Higuchi models, respectively. The thermodynamic parameters corroborate these findings, revealing that the AmB release from the evaluated systems was an endothermic and non-spontaneous process. Thermodynamic parameters can be used to explain the drug kinetic release profiles. Such an approach is of utmost importance for DDS containing insoluble compounds, such as AmB, which is associated with an erratic bioavailability.

  6. Shape-Memory-Alloy Release Mechanism

    NASA Technical Reports Server (NTRS)

    Mckinnis, Darin

    1993-01-01

    Release-nut mechanism activated by electric current applied to shape-memory alloy. Separates attached objects quickly by remote control. Does not create hazard or cause damage. Shape-memory release-nut mechanism unaffected by moisture or vacuum. Requires sustained current lasting 5 seconds or longer, and insensitive to electromagnetic interference. Mechanism can be reused.

  7. In the Stocks: Perilous Press Releases.

    ERIC Educational Resources Information Center

    Morton, Linda P.; Loving, Bill

    1994-01-01

    Reviews some of the legal responsibilities of public relations practitioners in the preparation of press releases. Discusses legal criteria for judging the fraudulence of press releases and discusses the timeframe for fraudulent action. Concludes with lessons that practitioners need to understand. (SR)

  8. A1C Test and Diabetes

    MedlinePlus

    ... Diagnosis The A1C Test & Diabetes The A1C Test & Diabetes What is the A1C test? The A1C test ... A1C test be used to diagnose type 2 diabetes and prediabetes? Yes. In 2009, an international expert ...

  9. Blood Test: Hemoglobin A1C

    MedlinePlus

    ... TV, Video Games, and the Internet Blood Test: Hemoglobin A1c KidsHealth > For Parents > Blood Test: Hemoglobin A1c Print A A A What's in this ... de sangre: hemoglobina A1c What It Is A hemoglobin A1c (HbA1c) test is used to monitor long- ...

  10. Blood Test: Hemoglobin A1C

    MedlinePlus

    ... Your 1- to 2-Year-Old Blood Test: Hemoglobin A1c KidsHealth > For Parents > Blood Test: Hemoglobin A1c A A A What's in this article? ... de sangre: hemoglobina A1c What It Is A hemoglobin A1c (HbA1c) test is used to monitor long- ...

  11. Calcium release from experimental dental materials.

    PubMed

    Okulus, Zuzanna; Buchwald, Tomasz; Voelkel, Adam

    2016-11-01

    The calcium release from calcium phosphate-containing experimental dental restorative materials was examined. The possible correlation of ion release with initial calcium content, solubility and degree of curing (degree of conversion) of examined materials was also investigated. Calcium release was measured with the use of an ion-selective electrode in an aqueous solution. Solubility was established by the weighing method. Raman spectroscopy was applied for the determination of the degree of conversion, while initial calcium content was examined with the use of energy-dispersive spectroscopy. For examined materials, the amount of calcium released was found to be positively correlated with solubility and initial calcium content. It was also found that the degree of conversion does not affect the ability of these experimental composites to release calcium ions.

  12. Quantification of Energy Release in Composite Structures

    NASA Technical Reports Server (NTRS)

    Minnetyan, Levon; Chamis, Christos C. (Technical Monitor)

    2003-01-01

    Energy release rate is usually suggested as a quantifier for assessing structural damage tolerance. Computational prediction of energy release rate is based on composite mechanics with micro-stress level damage assessment, finite element structural analysis and damage progression tracking modules. This report examines several issues associated with energy release rates in composite structures as follows: Chapter I demonstrates computational simulation of an adhesively bonded composite joint and validates the computed energy release rates by comparison with acoustic emission signals in the overall sense. Chapter II investigates the effect of crack plane orientation with respect to fiber direction on the energy release rates. Chapter III quantifies the effects of contiguous constraint plies on the residual stiffness of a 90 deg ply subjected to transverse tensile fractures. Chapter IV compares ICAN and ICAN/JAVA solutions of composites. Chapter V examines the effects of composite structural geometry and boundary conditions on damage progression characteristics.

  13. Quantification of Energy Release in Composite Structures

    NASA Technical Reports Server (NTRS)

    Minnetyan, Levon

    2003-01-01

    Energy release rate is usually suggested as a quantifier for assessing structural damage tolerance. Computational prediction of energy release rate is based on composite mechanics with micro-stress level damage assessment, finite element structural analysis and damage progression tracking modules. This report examines several issues associated with energy release rates in composite structures as follows: Chapter I demonstrates computational simulation of an adhesively bonded composite joint and validates the computed energy release rates by comparison with acoustic emission signals in the overall sense. Chapter II investigates the effect of crack plane orientation with respect to fiber direction on the energy release rates. Chapter III quantifies the effects of contiguous constraint plies on the residual stiffness of a 90 ply subjected to transverse tensile fractures. Chapter IV compares ICAN and ICAN/JAVA solutions of composites. Chapter V examines the effects of composite structural geometry and boundary conditions on damage progression characteristics.

  14. Dust release from surfaces exposed to plasma

    SciTech Connect

    Flanagan, T. M.; Goree, J.

    2006-12-15

    Micrometer-sized particles adhered to a surface can be released when exposed to plasma. In an experiment with a glass surface coated with lunar-simulant dust, it was found that particle release requires exposure to both plasma and an electron beam. The dust release rate diminishes almost exponentially in time, which is consistent with a random process. As proposed here, charges of particles adhered to the surface fluctuate. These charges experience a fluctuating electric force that occasionally overcomes the adhesive van der Waals force, causing particle release. The release rate increases with plasma density, so that plasma cleaning is feasible at high plasma densities. Applications of this cleaning include controlling particulate contamination in semiconductor manufacturing, dust mitigation in the exploration of the moon and Mars, and dusty plasmas.

  15. The vectorial release of nascent immunoglobulin peptides

    PubMed Central

    Bevan, Michael J.

    1971-01-01

    A microsomal preparation from a mouse plasmacytoma, MOPC 47A, that secretes immunoglobulin A was used to study the release of nascent immunoglobulin peptides in vitro. Nascent chains were released with puromycin and characterized with specific antiserum against the immunoglobulin product of the tumour. When the tissue had been prelabelled with [3H]leucine the experiments were complicated by the large background of completed radioactive polypeptides in the microsomal preparation. Up to one-third of the released radioactivity in the microsomal preparation could be recognized as immunoglobulin. With [3H]-puromycin as the radioactive label, however, the results are much easier to interpret, although the proportion of released radioactivity that can be identified as immunoglobulin is lower (up to one-tenth). Both types of experiment demonstrate that all of the recognizable nascent immunoglobulin chains remain in association with the microsomal vesicles after release from the ribosomes. PMID:5124814

  16. Environmental release summary (ERS) database CY 1997

    SciTech Connect

    Gleckler, B.P.

    1998-07-01

    This report discusses the Environmental Release Summary (ERS) database. The current needs of the Effluent and Environmental database is continually modified to fulfill monitoring (EEM) program (managed by Waste Management Federal Services of Hanford, Incorporated, Air and Water Services Organization). Changes are made to accurately calculate current releases, to affect how past releases are calculated. This document serves as a snap-shot of the database and software for the CY-1997 data and releases. This document contains all of the relevant data for calculating radioactive-airborne and liquid effluent. The ERS database is the official repository for the CY-1997 ERS release reports and the settings used to generate those reports. As part of the Tri-Party Agreement, FDH is committed to provide a hard copy of the ERS database for Washington State Department of Ecology, upon request. This document also serves as that hard copy for the last complete calendar year.

  17. How neurosecretory vesicles release their cargo.

    PubMed

    Scalettar, Bethe A

    2006-04-01

    Neurons and related cell types often contain two major classes of neurosecretory vesicles, synaptic vesicles (SVs) and dense-core granules (DCGs), which store and release distinct cargo. SVs store and release classic neurotransmitters, which facilitate propagation of action potentials across the synaptic cleft, whereas DCGs transport, store, and release hormones, proteins, and neuropeptides, which facilitate neuronal survival, synaptic transmission, and learning. Over the past few years, there has been a major surge in our understanding of many of the key molecular mechanisms underlying cargo release from SVs and DCGs. This surge has been driven largely by the use of fluorescence microscopy (especially total internal reflection fluorescence microscopy) to visualize SVs or DCGs in living cells. This review highlights some of the recent insights into cargo release from neurosecretory vesicles provided by fluorescence microscopy, with emphasis on DCGs.

  18. Nitric Oxide Release Part I. Macromolecular Scaffolds

    PubMed Central

    Riccio, Daniel A.; Schoenfisch, Mark H.

    2012-01-01

    Summary The roles of nitric oxide (NO) in physiology and pathophysiology merit the use of NO as a therapeutic for certain biomedical applications. Unfortunately, limited NO payloads, too rapid NO release, and the lack of targeted NO delivery have hindered the clinical utility of NO gas and low molecular weight NO donor compounds. A wide-variety of NO-releasing macromolecular scaffolds has thus been developed to improve NO’s pharmacological potential. In this tutorial review, we provide an overview of the most promising NO release scaffolds including protein, organic, inorganic, and hybrid organic-inorganic systems. The NO release vehicles selected for discussion were chosen based on their enhanced NO storage, tunable NO release characteristics, and potential as therapeutics. PMID:22362355

  19. Airway pressure release ventilation: theory and practice.

    PubMed

    Frawley, P M; Habashi, N M

    2001-05-01

    Airway pressure release ventilation (APRV) is a relatively new mode of ventilation, that only became commercially available in the United States in the mid-1990s. Airway pressure release ventilation produces tidal ventilation using a method that differs from any other mode. It uses a release of airway pressure from an elevated baseline to simulate expiration. The elevated baseline facilitates oxygenation, and the timed releases aid in carbon dioxide removal. Advantages of APRV include lower airway pressures, lower minute ventilation, minimal adverse effects on cardio-circulatory function, ability to spontaneously breathe throughout the entire ventilatory cycle, decreased sedation use, and near elimination of neuromuscular blockade. Airway pressure release ventilation is consistent with lung protection strategies that strive to limit lung injury associated with mechanical ventilation. Future research will probably support the use of APRV as the primary mode of choice for patients with acute lung injury.

  20. Superhydrophobic nitric oxide-releasing xerogels.

    PubMed

    Storm, Wesley L; Youn, Jonghae; Reighard, Katelyn P; Worley, Brittany V; Lodaya, Hetali M; Shin, Jae Ho; Schoenfisch, Mark H

    2014-08-01

    Superhydrophobic nitric oxide (NO)-releasing xerogels were prepared by spray-coating a fluorinated silane/silica composite onto N-diazeniumdiolate NO donor-modified xerogels. The thickness of the superhydrophobic layer was used to extend NO release durations from 59 to 105h. The resulting xerogels were stable, maintaining superhydrophobicity for up to 1month (the longest duration tested) when immersed in solution, with no leaching of silica or undesirable fragmentation detected. The combination of superhydrophobicity and NO release reduced viable Pseudomonas aeruginosa adhesion by >2-logs. The killing effect of NO was demonstrated at longer bacterial contact times, with superhydrophobic NO-releasing xerogels resulting in 3.8-log reductions in adhered viable bacteria vs. controls. With no observed toxicity to L929 murine fibroblasts, NO-releasing superhydrophobic membranes may be valuable antibacterial coatings for implants as they both reduce adhesion and kill bacteria that do adhere.

  1. Primary energy release. [during solar flares

    NASA Technical Reports Server (NTRS)

    Kahler, S.; Spicer, D.; Uchida, Y.; Zirin, H.

    1980-01-01

    The physical processes by which the magnetic energy of a solar active region is converted to other forms of energy in the appearance of a solar flare are discussed. Observations of the secondary manifestations of flare energy release, such as thermal plasmas and energetic particle emissions, are presented, with particular attention given to the temporal variations of flare radiation, the various forms of energy release, flare energy density, flare locations and sizes, energy distributions and H alpha, hard X-ray and microwave burst events. Current models of the primary energy release process are surveyed, and the models of Spicer (1976, 1977), which explains rapid flare energy release in terms of multiple tearing modes causing reconnection in sheared magnetic fields, and Uchida and Sakurai (1976, 1978), which attributes primary energy release to dynamic collapse caused by the interchange instability of the neutral sheet, are examined in detail.

  2. Ecological release in White Sands lizards

    PubMed Central

    Roches, S Des; Robertson, J M; Harmon, L J; Rosenblum, E B

    2011-01-01

    Ecological opportunity is any change that allows populations to escape selection from competition and predation. After encountering ecological opportunity, populations may experience ecological release: enlarged population size, broadened resource use, and/or increased morphological variation. We identified ecological opportunity and tested for ecological release in three lizard colonists of White Sands, New Mexico (Sceloporus undulatus, Holbrookia maculata, and Aspidoscelis inornata). First, we provide evidence for ecological opportunity by demonstrating reduced species richness and abundance of potential competitors and predators at White Sands relative to nearby dark soils habitats. Second, we characterize ecological release at White Sands by demonstrating density compensation in the three White Sands lizard species and expanded resource use in White Sands S. undulatus. Contrary to predictions from ecological release models, we observed directional trait change but not increased trait variation in S. undulatus. Our results suggest that ecological opportunity and ecological release can be identified in natural populations, especially those that have recently colonized isolated ecosystems. PMID:22393523

  3. Factors controlling gastric-glucagon release.

    PubMed Central

    Lefèbvre, P J; Luyckx, A S

    1977-01-01

    A system consisting of an isolated dog stomach perfused with whole blood has been designed to study gastric glucagon secretion. Under basal conditions, gastric glucagon release was 0.0-3.1 ng glucagon/100g of stomach per min. Arginine, at an arterial plasma concentration averaging 10 mM, elicited a rapid glucagon release. This gastric glucagon release was almost completely abolished by somatostatin (100 ng/ml). The release of gastric glucagon was not affected by hyperglycemia alone but was reduced by about 40% when hyperglycemia was concomitant with an hyperinsulinemia within the physiological range. These observations support the concept that adequate concentrations of insulin are necessary in order for hyperglycemia to inhibit gastric glucagon secretion. Furthermore, it is suggested that the isolated perfused dog stomach might provide a unique tool permitting investigation of alpha-cell function in the absence of endogenously released insulin. PMID:845258

  4. Gas release and conductivity modification studies

    NASA Technical Reports Server (NTRS)

    Linson, L. M.; Baxter, D. C.

    1979-01-01

    The behavior of gas clouds produced by releases from orbital velocity in either a point release or venting mode is described by the modification of snowplow equations valid in an intermediate altitude regime. Quantitative estimates are produced for the time dependence of the radius of the cloud, the average internal energy, the translational velocity, and the distance traveled. The dependence of these quantities on the assumed density profile, the internal energy of the gas, and the ratio of specific heats is examined. The new feature is the inclusion of the effect of the large orbital velocity. The resulting gas cloud models are used to calculate the characteristics of the field line integrated Pedersen conductivity enhancements that would be produced by the release of barium thermite at orbital velocity in either the point release or venting modes as a function of release altitude and chemical payload weight.

  5. A Rapid Test for Prediction of Nutrient Release from Controlled Release Fertilizers

    USDA-ARS?s Scientific Manuscript database

    Nutrient release from soluble granular fertilizers can be modified by polymer coating. The coating technology can be fine-tuned to change the duration (3 to 9 months) and rate of nutrient release, hence these products are termed as controlled release fertilizers (CRF). There is a need to develop a r...

  6. Measure your septa release ratios: pheromone release ratio variability affected by rubber septa and solvent

    USDA-ARS?s Scientific Manuscript database

    The type of solvent and volume of the solvent used to load pheromone/volatile components onto rubber septa had significant effects on release ratios, the variability of those release ratios, and the recoverability of the volatile components during subsequent extraction with hexane. Volatile release ...

  7. Pharmacokinetics and pharmacodynamics of once-daily controlled-release oxybutynin and immediate-release oxybutynin.

    PubMed

    Reiz, Joseph L; Salem, Paulette; Darke, Andrew C

    2007-03-01

    Oxybutynin is used to treat patients with urinary urgency, frequency, and urge incontinence. In this 2-way, multiple-dose, crossover study, the pharmacokinetics and pharmacodynamics of once-daily controlled-release oxybutynin were compared with immediate-release oxybutynin. Eighteen healthy male volunteers received one 15-mg controlled-release oxybutynin tablet once daily for 5 days or one 5-mg immediate-release oxybutynin tablet every 8 hours for 5 days. The washout period between treatments was > or =7 days. The mean steady-state AUC for oxybutynin following controlled-release oxybutynin treatment was higher (73.0 ng.h/mL) than following immediate-release oxybutynin treatment (53.6 ng.h/mL) (P = .0001). The mean C(max) was lower for controlled-release oxybutynin (5.7 ng/mL) than for immediate-release oxybutynin (7.5 ng/mL) (P = .0051), with a smaller fluctuation in oxybutynin plasma concentration for controlled-release oxybutynin (135.6%) than for immediate-release oxybutynin (319.3%) (P = .0001). Mean stimulated saliva output was greater for controlled-release oxybutynin, and mean dry mouth severity was less than immediate-release oxybutynin.

  8. Thermoresponsive latexes for fragrance encapsulation and release.

    PubMed

    Popadyuk, N; Popadyuk, A; Kohut, A; Voronov, A

    2016-04-01

    To synthesize cross-linked latex particles protecting the encapsulated fragrance at ambient temperatures and facilitating the release of cargo at the temperature of the surface of the skin that varies in different regions of the body between 33.5 and 36.9°C. Poly(stearyl acrylate) (PSA), a polymer with long crystallizable alkyl side chains (undergoes order-disorder transitions at 45°C), was chosen as the main component of the polymer particles. As a result, new thermoresponsive polymer particles for fragrance encapsulation were synthesized and characterized, including assessing the performance of particles in triggered release by elevated temperature. To obtain network domains of various crystallinity, stearyl acrylate was copolymerized with dipropylene glycol acrylate caprylate (DGAC) (comonomer) in the presence of a dipropylene glycol diacrylate sebacate (cross-linker) using the miniemulsion process. Comonomers and a cross-linker were mixed directly in a fragrance during polymerization. Fragrance release was evaluated at 25, 31, 35 and 39°C to demonstrate a new material potential in personal/health care skin-related applications. Particles protect the fragrance from evaporation at 25°C. The fragrance release rate gradually increases at 31, 35 and 39°C. Two slopes were found on release plots. The first slope corresponds to a rapid fragrance release. The second slope indicates a subsequent reduction in the release rate. Crystalline-to-amorphous transition of PSA triggers the release of fragrances from cross-linked latex particles at elevated temperatures. The presence of the encapsulated fragrance, as well as the inclusion of amorphous fragments in the polymer network, reduces the particle crystallinity and enhances the release. Release profiles can be tuned by temperature and controlled by the amount of loaded fragrance and the ratio of comonomers in the feed mixture. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  9. [Preparation and release mechanism of gestodene reservoir-type intravaginal rings].

    PubMed

    Li, Chun-Xiao; Wang, Yan-Kun; Ning, Mei-Ying

    2014-03-01

    This study taking gestodene (GEST) as a model, investigated the factors affecting reservoir-type intravaginal ring (IVR)'s drug release. This paper reported a gestodene intravaginal ring of reservoir design, comprising a gestodene silicone elastomer core encased in a non-medicated silicone sheath, separately manufactured by reaction injection moulding at 80 degrees C and heating vulcanization at 130 degrees C is reported. The test investigated the factors affecting drug release through a single variable method, taking the drug release rates of 21 days as standards. When changing the thickness of the controlling sheath outside, the ratio of the first day of drug release and mean daily release (MDR), named the relatively burst effect, is closing to 1 with the thickness of controlling sheath increasing, while the 1.25 mm sheath corresponding to 1.04 controlled the burst release effectively; a positive correlation (r = 0.992 2) existed between the average drug release (Q/t) and drug loading (A) within a certain range. The C6-165 controlling sheath with high solubility of GEST is easier to achieve controlled release of the drug; GEST crystalline power is more effective to implement controlled release of drugs among difficent states of the drug. A 1/4 fractional segment core gives a relatively burst effect of 1.76, while the 1/1 and 1/2 are 1.93 and 1.87 separately, at the same drug loading, concluding that use of a fractional segment core would allow development of a suitable GEST reservoir IVR. In summary, GEST reservoir-type IVR could be adjusted by the thickness of controlling sheath, the loading of drug, the material properties of controlling sheath, the dispersion state of drug, the additive composition and structure of intravaginal ring, to control the drug release behavior and achieve the desired drug release rate.

  10. Dynamic compression and volatile release of carbonates

    NASA Technical Reports Server (NTRS)

    Tyburczy, J. A.; Ahrens, T. J.

    1984-01-01

    Particle velocity profiles upon shock compression and isentropic releases were measured for polycrystalline calcite. The Solenhofen limestone release paths lie, close to the Hugoniot. Calcite 3 to 2 transition, upon release, was observed, but rarefaction shocks were not detected. The equation of state is used to predict the fraction of material devolatilized upon isentropic release as a function of shock pressure. The effect of ambient partial pressure of CO2 on the calculations is demonstrated and considered in models of atmospheric evolution by impact induced mineral devolatilization. The radiative characteristics of shocked calcite indicate that localization of thermal energy occurs under shock compression. Shock entropy calculations result in a minimum estimate of 90% devolatilization upon complete release from 10 GPa. Isentropic release paths from calculated continuum Hugoniot temperatures cross into the CaO (solid) + CO2 (vapor) field at improbably low pressures. It is found that release paths from measured shock temperatures cross into the melt plus vapor field at pressures greater than .5 GPa, which suggests that devolatilization is initiated at the shear banding sites.

  11. Fission product release mechanisms and pathways

    SciTech Connect

    Malinauskas, A.P.

    1981-01-01

    It is axiomatic that the severity of a nuclear reactor accident is determined by the extent of radioactivity escape which results. The main focus of site safety analyses is thus on fission product release and transport. Of all the processes involved, fission product escape from the fuel-cladding region into the primary coolant circuit is perhaps the most simple to describe; even so, it is an extremely complex function of the time/temperature history of the fuel-cladding system during an accident, since many mechanisms for release are involved. Depending upon the particular fission product species, these release mechanisms range from simple gaseous expansion processes at low temperatures to evaporation-condensation processes (aerosol formation) over molten fuel. Because of these complexities, it is convenient to subdivide the time/temperature sequence of an accident into more or less discrete phases over which specific release mechanisms dominate. Four such phases are the periods of (1) gap release, (2) meltdown release, (3) vaporization, and (4) oxidation release. This approach simplifies the problem considerably, although some loss of uniformity results. The methodology applies to BWR and PWR reactors with appropriate adaptations.

  12. Accelerated in-vitro release testing methods for extended-release parenteral dosage forms.

    PubMed

    Shen, Jie; Burgess, Diane J

    2012-07-01

    This review highlights current methods and strategies for accelerated in-vitro drug release testing of extended-release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in-situ depot-forming systems and implants. Extended-release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, 'real-time' in-vitro release tests for these dosage forms are often run over a long time period. Accelerated in-vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in-vitro release methods using United States Pharmacopeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended-release parenteral dosage forms, along with the accelerated in-vitro release testing methods currently employed are discussed. Accelerated in-vitro release testing methods with good discriminatory ability are critical for quality control of extended-release parenteral products. Methods that can be used in the development of in-vitro-in-vivo correlation (IVIVC) are desirable; however, for complex parenteral products this may not always be achievable. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

  13. Accelerated in vitro release testing methods for extended release parenteral dosage forms

    PubMed Central

    Shen, Jie; Burgess, Diane J.

    2012-01-01

    Objectives This review highlights current methods and strategies for accelerated in vitro drug release testing of extended release parenteral dosage forms such as polymeric microparticulate systems, lipid microparticulate systems, in situ depot-forming systems, and implants. Key findings Extended release parenteral dosage forms are typically designed to maintain the effective drug concentration over periods of weeks, months or even years. Consequently, “real-time” in vitro release tests for these dosage forms are often run over a long time period. Accelerated in vitro release methods can provide rapid evaluation and therefore are desirable for quality control purposes. To this end, different accelerated in vitro release methods using United States Pharmacopoeia (USP) apparatus have been developed. Different mechanisms of accelerating drug release from extended release parenteral dosage forms, along with the accelerated in vitro release testing methods currently employed are discussed. Conclusions Accelerated in vitro release testing methods with good discriminatory ability are critical for quality control of extended release parenteral products. Methods that can be used in the development of in vitro-in vivo correlation (IVIVC) are desirable, however for complex parenteral products this may not always be achievable. PMID:22686344

  14. Rechargeable calcium phosphate orthodontic cement with sustained ion release and re-release

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Weir, Michael D.; Chow, Laurence C.; Reynolds, Mark A.; Xu, Hockin H. K.

    2016-11-01

    White spot lesions (WSL) due to enamel demineralization are major complications for orthodontic treatments. Calcium phosphate (CaP) dental resins with Ca and P ion releases are promising for remineralization. However, previous Ca and P releases lasted for only weeks. Experimental orthodontic cements were developed using pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA) at mass ratio of 1:1 (PE); and PE plus 10% of 2-hydroxyethyl methacrylate (HEMA) and 5% of bisphenol A glycidyl dimethacrylate (BisGMA) (PEHB). Particles of amorphous calcium phosphate (ACP) were incorporated into PE and PEHB at 40% filler level. Specimens were tested for bracket-enamel shear bond strength, water sorption, CaP release, and ion recharge and re-release. PEHB+40ACP had higher bracket-enamel bond strength and ion release and rechargeability than PE+40ACP. ACP incorporation into the novel orthodontic cement did not adversely affect the bracket-enamel bond strength. Ion release and re-release from the novel ACP orthodontic cement indicated favorable release and re-release patterns. The recharged orthodontic cement could release CaP ions continuously for four weeks without further recharge. Novel rechargeable orthodontic cement containing ACP was developed with a high bracket-enamel bond strength and the ability to be repeatedly recharged to maintain long-term high levels of CaP ion releases.

  15. Compressive strength, fluoride release and recharge of fluoride-releasing materials.

    PubMed

    Xu, Xiaoming; Burgess, John O

    2003-06-01

    The compressive strength, fluoride releases and recharge profiles of 15 commercial fluoride-releasing restorative materials have been studied. The materials include glass ionomers (Fuji IX, Ketac Molar, Ketac Silver, and Miracle Mix), resin-modified glass ionomers (Fuji II LC Improved, Photac-Fil, and Vitremer), compomers (Compoglass, Dyract AP, F2000, and Hytac) and composite resins (Ariston pHc, Solitaire, Surefil and Tetric Ceram). A negative linear correlation was found between the compressive strength and fluoride release (r(2)=0.7741), i.e., restorative materials with high fluoride release have lower mechanical properties. The fluoride-releasing ability can be partially regenerated or recharged by using a topical fluoride agent. In general, materials with higher initial fluoride release have higher recharge capability (r(2)=0.7088). Five equations have been used in curve fitting to describe the cumulative fluoride release from different materials. The equation [F](c)=[F](I)(1-e(-bt))+betat best describes the cumulative fluoride release for most glass ionomers, resin-modified glass ionomers, and some high fluoride-releasing compomers and composites, whereas [F](c)=[F](I)/(t(1/2)+t)+alphat best describes the cumulative fluoride release for most compomers and composite resins. The clinic applications of different fluoride-releasing materials have also been discussed.

  16. Rechargeable calcium phosphate orthodontic cement with sustained ion release and re-release

    PubMed Central

    Zhang, Ling; Weir, Michael D.; Chow, Laurence C.; Reynolds, Mark A.; Xu, Hockin H. K.

    2016-01-01

    White spot lesions (WSL) due to enamel demineralization are major complications for orthodontic treatments. Calcium phosphate (CaP) dental resins with Ca and P ion releases are promising for remineralization. However, previous Ca and P releases lasted for only weeks. Experimental orthodontic cements were developed using pyromellitic glycerol dimethacrylate (PMGDM) and ethoxylated bisphenol A dimethacrylate (EBPADMA) at mass ratio of 1:1 (PE); and PE plus 10% of 2-hydroxyethyl methacrylate (HEMA) and 5% of bisphenol A glycidyl dimethacrylate (BisGMA) (PEHB). Particles of amorphous calcium phosphate (ACP) were incorporated into PE and PEHB at 40% filler level. Specimens were tested for bracket-enamel shear bond strength, water sorption, CaP release, and ion recharge and re-release. PEHB+40ACP had higher bracket-enamel bond strength and ion release and rechargeability than PE+40ACP. ACP incorporation into the novel orthodontic cement did not adversely affect the bracket-enamel bond strength. Ion release and re-release from the novel ACP orthodontic cement indicated favorable release and re-release patterns. The recharged orthodontic cement could release CaP ions continuously for four weeks without further recharge. Novel rechargeable orthodontic cement containing ACP was developed with a high bracket-enamel bond strength and the ability to be repeatedly recharged to maintain long-term high levels of CaP ion releases. PMID:27808251

  17. Nutrient Sensing Overrides Somatostatin and Growth Hormone-Releasing Hormone to Control Pulsatile Growth Hormone Release.

    PubMed

    Steyn, F J

    2015-07-01

    Pharmacological studies reveal that interactions between hypothalamic inhibitory somatostatin and stimulatory growth hormone-releasing hormone (GHRH) govern pulsatile GH release. However, in vivo analysis of somatostatin and GHRH release into the pituitary portal vasculature and peripheral GH output demonstrates that the withdrawal of somatostatin or the appearance of GHRH into pituitary portal blood does not reliably dictate GH release. Consequently, additional intermediates acting at the level of the hypothalamus and within the anterior pituitary gland are likely to contribute to the release of GH, entraining GH secretory patterns to meet physiological demand. The identification and validation of the actions of such intermediates is particularly important, given that the pattern of GH release defines several of the physiological actions of GH. This review highlights the actions of neuropeptide Y in regulating GH release. It is acknowledged that pulsatile GH release may not occur selectively in response to hypothalamic control of pituitary function. As such, interactions between somatotroph networks, the median eminence and pituitary microvasculature and blood flow, and the emerging role of tanycytes and pericytes as critical regulators of pulsatility are considered. It is argued that collective interactions between the hypothalamus, the median eminence and pituitary vasculature, and structural components within the pituitary gland dictate somatotroph function and thereby pulsatile GH release. These interactions may override hypothalamic somatostatin and GHRH-mediated GH release, and modify pulsatile GH release relative to the peripheral glucose supply, and thereby physiological demand.

  18. Feeding Releases Endogenous Opioids in Humans.

    PubMed

    Tuulari, Jetro J; Tuominen, Lauri; de Boer, Femke E; Hirvonen, Jussi; Helin, Semi; Nuutila, Pirjo; Nummenmaa, Lauri

    2017-08-23

    The endogenous opioid system supports a multitude of functions related to appetitive behavior in humans and animals, and it has been proposed to govern hedonic aspects of feeding thus contributing to the development of obesity. Here we used positron emission tomography to investigate whether feeding results in hedonia-dependent endogenous opioid release in humans. Ten healthy males were recruited for the study. They were scanned with the μ-opioid-specific ligand [(11)C]carfentanil three times, as follows: after a palatable meal, a nonpalatable meal, and after an overnight fast. Subjective mood, satiety, and circulating hormone levels were measured. Feeding induced significant endogenous opioid release throughout the brain. This response was more pronounced following a nonpalatable meal versus a palatable meal, and independent of the subjective hedonic responses to feeding. We conclude that feeding consistently triggers cerebral opioid release even in the absence of subjective pleasure associated with feeding, suggesting that metabolic and homeostatic rather than exclusively hedonic responses play a role in the feeding-triggered cerebral opioid release.SIGNIFICANCE STATEMENT The endogenous opioid system supports both hedonic and homeostatic functions. It has been proposed that overeating and concomitant opioid release could downregulate opioid receptors and promote the development of obesity. However, it remains unresolved whether feeding leads to endogenous opioid release in humans. We used in vivo positron emission tomography to test whether feeding triggers cerebral opioid release and whether this response is associated with pleasurable sensations. We scanned volunteers using the μ-opioid receptor-specific radioligand [(11)C]carfentanil three times, as follows: after an overnight fast, after consuming a palatable meal, and after consuming a nonpalatable meal. Feeding led to significant endogenous opioid release, and this occurred also in the absence of feeding

  19. [Nutrient release characteristics and use efficiency of slow- and controlled release fertilizers].

    PubMed

    Duan, Lu-Lu; Zhang, Min; Liu, Gang; Shang, Zhao-Cong; Yang, Yi

    2009-05-01

    Water extraction method and soil incubation method were used to study the nutrient release characteristics of four slow- and controlled release fertilizers (CRF1, CRF2, SCU, and IBDU), and pot experiment was conducted to assess the effects of the release characteristics on the nutrient requirements of canola (Brassica napus L.). The nutrient release curves of test fertilizers in water were S pattern for CRF1 and CRF2, burst pattern for SCU, and reverse L pattern for IBDU. The nutrient release characteristics of the four fertilizers in water and in soil all fitted binomial equations, suggesting that there existed some similarities in the nutrient release in the two media. The nutrient uptake and biomass of canola plants treated with CRF1 and CRF2 were significantly higher than those treated with SCU and IBDU, and CRF2 had the greatest effect. The nutrient release curves of CRF1 and CRF2 accorded more closely with the nutrient requirements of canola.

  20. Dual drug release from hydrogels covalently containing polymeric micelles that possess different drug release properties.

    PubMed

    Murata, Mari; Uchida, Yusuke; Takami, Taku; Ito, Tomoki; Anzai, Ryosuke; Sonotaki, Seiichi; Murakami, Yoshihiko

    2017-05-01

    In the present study, we designed hydrogels for dual drug release: the hydrogels that covalently contained the polymeric micelles that possess different drug release properties. The hydrogels that were formed from polymeric micelles possessing a tightly packed (i.e., well-entangled) inner core exhibited a higher storage modulus than the hydrogels that were formed from the polymeric micelles possessing a loosely packed structure. Furthermore, we conducted release experiments and fluorescent observations to evaluate the profiles depicting the release of two compounds, rhodamine B and auramine O, from either polymeric micelles or hydrogels. According to our results, (1) hydrogels that covalently contains polymeric micelles that possess different drug release properties successfully exhibit the independent release behaviors of the two compounds and (2) fluorescence microscopy can greatly facilitate efforts to evaluate drug release properties of materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Antibiotic releasing biodegradable scaffolds for osteomyelitis.

    PubMed

    Nair, Manitha; Krishnan, Amit

    2014-01-01

    Osteomyelitis is characterized by progressive inflammatory bone degeneration. In the management of chronic osteomyelitis, it is necessary to remove the infected bone tissue followed by implantation of an antibiotic releasing biomaterial that can release antibiotic locally for long periods of time. The main carrier used in clinics for this application is polymethylmethacrylate (PMMA) (Eg. Septopal beads). However, major drawback is the need of an additional surgery to remove the beads after therapy, as PMMA is not biodegradable. This necessitates the requirement of biodegradable carrier systems that can release antibiotics and simultaneously support debrided bone formation. This review summarizes biodegradable carrier systems that have been reported for the localised treatment and prophylaxis of osteomyelitis.

  2. [Effect of release of hydroxypropylmethyl cellulose on single and bilayer sustained-release matrix tablets].

    PubMed

    Yang, Ya-peng; Wang, Meng-yuan; Chang, Jun-biao; Guo, Min-tong

    2013-04-18

    To study the influence of HPMC as hydrophilic matrix materials and controlled-layer components on the drug release of sustained-release matrix tablets and bilayer tablets. Diltiazem hydrochloride was chosen as the water-soluble model drug to prepare different kinds of matrix tablets and double layer tablets with different formulations, and evaluate how the levels and grades of HPMC affect the drug release in sustained-release tablets and bilayer tablets. HPMC with high viscosity and the amount of 20%-40% could delay the drug release to certain degree, but it was difficult to further slow down the drug release up to 24 h, especially for a water soluble drug. Combining HPMC with 5%-20% of CMC-Na was proven to be an effective way to achieve the 24 h release profile with the water soluble drug. HPMC was also investigated as a component in the double layer tablet as base layer. Drug release was complicated compared with EC as the base layer in the double layer tablet due to the great swelling ability of HPMC. HPMC's larger swilling let it form a big cap to retard the drug release, which could significantly affect the drug release with a large ratio of the base layer to the drug layer; furthermore increasing the quality of 10%-40% of the base layer and the proportion of HPMC could reduce the initial burst release. The grade/level of HPMC and combinations with other matrix materials had a big impact on the drug release. HPMC could be used in the base layer of the double tablet to alternate the drug release profile, and reduce the initial burst release of the double-layer matrix tablet, and potentially change the drug mechanism.

  3. Alcohol inhibits luteinizing hormone-releasing hormone release by activating the endocannabinoid system

    PubMed Central

    Fernández-Solari, Javier; Scorticati, Camila; Mohn, Claudia; De Laurentiis, Andrea; Billi, Silvia; Franchi, Ana; McCann, Samuel M.; Rettori, Valeria

    2004-01-01

    We hypothesized that ethanol (EtOH) might act through the endocannabinoid system to inhibit luteinizing hormone-releasing hormone (LHRH) release. Therefore, we examined the mechanism by which EtOH and anandamide (AEA), an endogenous cannabinoid, inhibit LHRH release from incubated medial basal hypothalamic explants. In previous work, we demonstrated that EtOH inhibits the N-methyl-d-aspartic acid-stimulated release of LHRH by increasing the release of two neurotransmitters: β-endorphin and γ-aminobutyric acid (GABA). In the present work, bicuculline, a GABAergic antagonist, completely prevented the inhibition of AEA (10-9M) on N-methyl-d-aspartic acid-induced LHRH release, but naltrexone, a μ-opioid receptor antagonist, had no effect. AEA also significantly increased GABA release but had no effect on β-endorphin release. Therefore, AEA could inhibit LHRH release by increasing GABA but not β-endorphin release. Because EtOH and AEA acted similarly to inhibit LHRH release, we investigated whether both substances would affect the adenylate cyclase activity acting through the same GTP-coupled receptors, the cannabinoid receptors 1 (CB1-rs). AEA and EtOH (10-1M) reduced the forskolin-stimulated accumulation of cAMP, but AM251, a specific antagonist of CB1-r, significantly blocked that inhibition. Additionally we investigated whether CB1-r is involved in the inhibition of LHRH by EtOH and AEA. AEA and EtOH reduced forskolin-stimulated LHRH release, but AM251 significantly blocked that inhibition. Also, we demonstrated that EtOH did not act by increasing AEA synthase activity to inhibit LHRH release in our experimental conditions. Therefore, our results indicate that EtOH inhibits the release of LHRH acting through the endocannabinoid system. PMID:14981261

  4. Characterisation of a flavonoid ligand of the fungal protein Alt a 1

    PubMed Central

    Garrido-Arandia, María; Silva-Navas, Javier; Ramírez-Castillejo, Carmen; Cubells-Baeza, Nuria; Gómez-Casado, Cristina; Barber, Domingo; Pozo, Juan C.; Melendi, Pablo G.; Pacios, Luis F.; Díaz-Perales, Araceli

    2016-01-01

    Spores of pathogenic fungi are virtually ubiquitous and cause human disease and severe losses in crops. The endophytic fungi Alternaria species produce host-selective phytotoxins. Alt a 1 is a strongly allergenic protein found in A. alternata that causes severe asthma. Despite the well-established pathogenicity of Alt a 1, the molecular mechanisms underlying its action and physiological function remain largely unknown. To gain insight into the role played by this protein in the pathogenicity of the fungus, we studied production of Alt a 1 and its activity in spores. We found that Alt a 1 accumulates inside spores and that its release with a ligand is pH-dependent, with optimum production in the 5.0–6.5 interval. The Alt a 1 ligand was identified as a methylated flavonoid that inhibits plant root growth and detoxifies reactive oxygen species. We also found that Alt a 1 changes its oligomerization state depending on the pH of the surrounding medium and that these changes facilitate the release of the ligand. Based on these results, we propose that release of Alt a 1 should be a pathogenic target in approaches used to block plant defenses and consequently to favor fungal entry into the plant. PMID:27633190

  5. Opioid/naloxone prolonged release combinations for opioid induced constipation.

    PubMed

    Kapoor, Shailendra

    2012-08-07

    I read with great interest the recent article by Chen et al in a recent issue of your esteemed journal. The article is highly thought provoking. One emerging therapeutic alternative for opioid induced constipation is the emergence of opioid/naloxone prolonged release combinations. For instance, naloxone when administered in a 1:2 ratio with oxycodone reverses the inhibitory effect of oxycodone on the gastrointestinal tract. The advantage of oxycodone/naloxone prolonged release (OXN) is that while its anti-nociceptive efficacy is equivalent to that of oxycodone prolonged release (OXC), it significantly decreases the "Bowel Function Index" thereby ameliorating symptoms of opioid induced constipation to a large extent. Schutter et al in a recent study have reported a decrease in the bowel function index from 38.2 to 15.1. Similarly, Löwenstein et al in another recent study have reported that following a month of therapy, complete spontaneous bowel movements per week is increased from one in OXC therapy to three in OXN therapy.

  6. PCCs Release First Data Set - TCGA

    Cancer.gov

    A component of the TCGA Research Network, the Protein Characterization Centers (PCCs), also part of NCI’s Clinical Proteome Tumor Analysis Consortium, has released the proteomic data generated from TCGA’s colorectal cancer samples.

  7. Environmentally friendly slow-release nitrogen fertilizer.

    PubMed

    Ni, Boli; Liu, Mingzhu; Lü, Shaoyu; Xie, Lihua; Wang, Yanfang

    2011-09-28

    To sustain the further world population, more fertilizers are required, which may become an environmental hazard, unless adequate technical and socioeconomic impacts are addressed. In the current study, slow-release formulations of nitrogen fertilizer were developed on the basis of natural attapulgite (APT) clay, ethylcellulose (EC) film, and sodium carboxymethylcellulose/hydroxyethylcellulose (CMC/HEC) hydrogel. The structural and chemical characteristics of the product were examined. The release profiles of urea, ammonium sulfate, and ammonium chloride as nitrogen fertilizer substrates were determined in soil. To further compare the release profiles of nitrogen from different fertilizer substrates, a mathematical model for nutrient release from the coated fertilizer was applied to calculate the diffusion coefficient D. The influence of the product on water-holding and water-retention capacities of soil was determined. The experimental data indicated that the product can effectively reduce nutrient loss, improve use efficiency of water, and prolong irrigation cycles in drought-prone environments.

  8. Emergency Response to Gold King Mine Release

    EPA Pesticide Factsheets

    Description of August 5, 2015 release of contaminated waters from the Gold King Mine into Cement Creek and the Animas River, and the resulting emergency response remediation efforts, including monitoring of affected waterways.

  9. The low synaptic release probability in vivo.

    PubMed

    Borst, J Gerard G

    2010-06-01

    The release probability, the average probability that an active zone of a presynaptic terminal releases one or more vesicles following an action potential, is tightly regulated. Measurements in cultured neurons or in slices indicate that this probability can vary greatly between synapses, but on average it is estimated to be as high as 0.5. In vivo, however, the size of synaptic potentials is relatively independent of recent history, suggesting that release probability is much lower. Possible causes for this discrepancy include maturational differences, a higher spontaneous activity, a lower extracellular calcium concentration and more prominent tonic inhibition by ambient neurotransmitters during in vivo recordings. Existing evidence thus suggests that under physiological conditions in vivo, presynaptic action potentials trigger the release of neurotransmitter much less frequently than what is observed in in vitro preparations.

  10. 49 CFR 236.791 - Release, value.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.791 Release, value. The electrical value at which the movable member of an electromagnetic device will move...

  11. Electromyography of arrow release in archery.

    PubMed

    Hennessy, M P; Parker, A W

    1990-01-01

    An electronic arrow movement detector was used to accurately locate the muscle activity associated with release of the arrow during shooting in archery. Digital computer analysis of the electromyograms from thirty shots for two archers facilitated an examination of the relationship between the measured activity of the muscles and their function during release. Changes present in the direct and integrated electromyograms of muscles acting at the wrist and elbow joints of the bow arm and the shoulder of the draw arm tended to anticipate the moment of arrow release. These changes would produce muscular force to reduce unwanted movement at this critical phase of the shot in the bow arm and initiate release of the bow string by the fingers. This study provides a detailed quantitative analysis of the muscular action of the technique and identifies possibilities for prevention of injury by improving the understanding of muscle action in shooting.

  12. VAP Development: Initiation, Development, Evaluation, and Release

    SciTech Connect

    Jensen, M; Collis, Fast, J; Flynn, C; Mather, J; McFarlane, S; Monroe, J; Sivaraman, C; Xie, S

    2011-02-23

    This white paper provides a plan to formalize the evaluation of newly developed VAPs and a framework for the development of value-added products through four different stages: Initiation, Development, Evaluation, and Release.

  13. Seismic energy release of the moon

    NASA Technical Reports Server (NTRS)

    Goins, N. R.; Dainty, A. M.; Toksoz, M. N.

    1981-01-01

    Lunar seismicity is investigated by calculating various source parameters for a number of shallow and deep-focus moonquakes. The seismic moment, seismic energy release, annual seismic energy release, stress drop, and body-wave magnitude are determined for the largest shallow moonquakes and for large deep-focus events. It is found that the shallow events dominate the lunar seismic energy release, that tidal dissipation may account for the energy release by the deep-focus events, and that the stress drops for the deep-focus events are comparable to or smaller than the calculated tidal stresses. A comparison of the results with terrestrial data indicates that the seismic characteristics of a planet are controlled more by tectonic style and state than by the relative magnitude of the driving forces.

  14. Arsenic Release from Foodstuffs upon Food Preparation.

    PubMed

    Cheyns, Karlien; Waegeneers, Nadia; Van de Wiele, Tom; Ruttens, Ann

    2017-03-22

    In this study the concentration of total arsenic (As) and arsenic species (inorganic As, arsenobetaine, dimethylarsinate, and methylarsonate) was monitored in different foodstuffs (rice, vegetables, algae, fish, crustacean, molluscs) before and after preparation using common kitchen practices. By measuring the water content of the foodstuff and by reporting arsenic concentrations on a dry weight base, we were able to distinguish between As release effects due to food preparation and As decrease due to changes in moisture content upon food preparation. Arsenic species were released to the broth during boiling, steaming, frying, or soaking of the food. Concentrations declined with maxima of 57% for total arsenic, 65% for inorganic As, and 32% for arsenobetaine. On the basis of a combination of our own results and literature data, we conclude that the extent of this release of arsenic species is species specific, with inorganic arsenic species being released most easily, followed by the small organic As species and the large organic As species.

  15. EPA Announces 2014 Toxics Release Inventory Report

    EPA Pesticide Factsheets

    DALLAS - (Feb. 1, 2016) In 2014, 93 percent of toxic waste from industrial facilities within U.S. Environmental Protection Agency (EPA) Region 6-Arkansas, Louisiana, Oklahoma, New Mexico, and Texas-was not released into the environment. Instead, the

  16. Environmental Releases Report for Calendar Year 1998

    SciTech Connect

    ROKKAN, D.J.

    1999-08-27

    This report fulfills the annual reporting requirements of US. Department of Energy (DOE) Order 5400.1, General Environmental Protection Program. It presents summaries of air emissions and liquid effluents released to the environment as well as nonroutine releases during calendar-year 1998 from facilities and activities managed by Fluor Daniel Hanford, Inc. (FDH), and Bechtel Hanford, Inc. (BHI). Besides the summaries, the report also has extensive data on those releases and the radioactive and hazardous substances they contained. These data were obtained from direct sampling and analysis and from estimations deriving from approved release factors. This report further serves as a supplemental resource to the Hanford Site Environmental Report (HSER, PNNL-12088), which gives a yearly accounting of the major activities and environmental status of the Hanford Site. The HSER documents the Hanford Site's state of compliance with applicable environmental regulations as well as describing the impacts of activities on the Site to the surrounding populace and environment.

  17. Biomechanical consequences of sequential plantar fascia release.

    PubMed

    Murphy, G A; Pneumaticos, S G; Kamaric, E; Noble, P C; Trevino, S G; Baxter, D E

    1998-03-01

    Plantar fascia release has long been a mainstay in the surgical treatment of persistent heel pain, although its effects on the biomechanics of the foot are not well understood. With the use of cadaver specimens and digitized computer programs, the changes in the medial and lateral columns of the foot and in the transverse arch were evaluated after sequential sectioning of the plantar fascia. Complete release of the plantar fascia caused a severe drop in the medial and lateral columns of the foot, compared with release of only the medial third. Equinus rotation of the calcaneus and a drop in the cuboid indicate that strain of the plantar calcaneocuboid joint capsule and ligament is a likely cause of lateral midfoot pain after complete plantar fascia release.

  18. EPA Announces 2014 Toxics Release Inventory Report

    EPA Pesticide Factsheets

    WASHINGTON -- In 2014, 84 of the 25 billion pounds of toxic chemical waste managed at the nation's industrial facilities was not released into the environment due to the use of preferred waste management practices like recycling, energy recovery an

  19. Member end releases in framed structures

    NASA Astrophysics Data System (ADS)

    Stallings, J. M.

    1993-02-01

    Discontinuities such as internal hinges are commonly encountered in framed structures. A general method of including discontinuities in stiffness method analyses of planar frames by the release of member end forces is developed. Modifications are made to the member stiffness matrix and equivalent joint load vector to account for the released end forces. A FORTRAN algorithm is given that makes the necessary modifications to the member stiffness matrix and equivalent joint load vector for the standard planar frame member. The algorithm allows combinations of up to three member end forces to be released (specified at zero or nonzero values). An algorithm is also given that calculates the unknown member end displacements at the released member end forces. Numerical examples are given to illustrate the uses and capabilities of the algorithms.

  20. CERCLA and EPCRA Continuous Release Reporting

    EPA Pesticide Factsheets

    Congress established reportable quantities for Superfund hazardous substances. A continuous release of a hazardous substance is defined as being without interruption or abatement and stable in quantity and rate.