Few-Cycle Pulses by External Compression

2004 ◽  
pp. 137-178 ◽  
Author(s):  
Sandro De Silvestri ◽  
Mauro Nisoli ◽  
Giuseppe Sansone ◽  
Salvatore Stagira ◽  
Orazio Svelto
Keyword(s):  
External Compression

Assessing the Impact of the Inlet Total Pressure Distortion on the Turbofan Thrust

2018 ◽  
pp. 19-30
Author(s):  
Yu. A. Ezrokhi ◽  
E. A. Khoreva
Keyword(s):  
Total Pressure ◽  
External Compression ◽  
Average Value ◽  
Inlet Distortion ◽  
Air Inlet ◽  
Engine Thrust ◽  
Relative Value ◽  
Main Effect ◽  
Pressure Recovery Factor ◽  
The Impact

The paper considers techniques to develop a mathematical model using a method of «parallel compressors». The model is intended to estimate the impact of the air inlet distortion on the primary parameters of the aero-engine.  The paper presents rated estimation results in the context of twin spool turbofan design for two typical cruiser modes of flight of the supersonic passenger jet. In estimation the base values σbase and the average values of the inlet ram recovery σave remained invariable. Thus, parametrical calculations were performed for each chosen relative value of the area of low-pressure region.The paper shows that an impact degree of the inlet distortion on the engine thrust for two modes under consideration is essentially different. In other words, if in the subsonic mode the impact assessment can be confined only to taking into account the influence of decreasing average values of the inlet total pressure, the use of such an assumption in the supersonic cruiser mode may result in considerable errors.With invariable values of the pressure recovery factor at the engine intake, which correspond to the speed of flight for a typical air inlet of external compression σbase, and average value σave, a parameter Δσuneven  has the main effect on the engine thrust, and degree of this effect essentially depends on a difference between σave and σbase values.

Clinical Experience with a New Nitinol Self-Expanding Stent in Peripheral Arteries

1996 ◽  
Vol 3 (4) ◽  
pp. 369-379 ◽  
Author(s):  
Michel Henry ◽  
Max Amor ◽  
Rafael Beyar ◽  
Isabelle Henry ◽  
Jean-Marc Porte ◽  
...  
Keyword(s):  
Long Term Results ◽  
Lesion Length ◽  
Secondary Patency ◽  
Peripheral Arteries ◽  
External Compression ◽  
Nitinol Stent ◽  
Nitinol Stents ◽  
The Mean

Purpose: To evaluate a new self-expanding nitinol coil stent in stenotic or occluded peripheral arteries. Methods: Seventy-three symptomatic patients (58 men; mean age 67 years) were treated with nitinol stents for lesions in the iliac artery (9 stenoses); superficial femoral artery (SFA) (39 stenoses, 6 occlusions); popliteal artery and tibioperoneal trunk (9 stenoses, 7 occlusions); and 3 bypass grafts. Mean diameter stenosis was 84.4% ± 9.9% (range 75% to 100%), and mean lesion length was 45 ± 23 mm (range 20 to 120 mm). Results: Eighty-eight 40-mm-long stents with diameters between 5 and 8 mm were implanted percutaneously for suboptimal dilation (n = 45); dissection (n = 21); and restenosis (n = 7). All stents but one were implanted successfully; the malpositioned stent was removed, and another stent was successfully deployed. There were 3 (4.1%) failures due to thrombosis at 24 hours. During the mean 16-month follow-up (range to 44 months), 4 restenoses (3 femoral, 1 popliteal) have occurred; 2 were treated with repeat dilation and 2 underwent bypass. Primary and secondary patency rates at 18 months were 87% and 90%, respectively, for all lesions (iliac: 100% for both; femoral: 85% and 88%; popliteal: 87% and 100%). Conclusions: This new nitinol stent seems to be safe and effective with favorable long-term results, even in distal SFA lesions and popliteal arteries. Its flexibility and resistance to external compression allow its placement in tortuous arteries and near joints.

scholarly journals A Case of Anterior Choroidal Artery Occlusion and Stroke Secondary to External Compression

2021 ◽  
pp. 369-374
Author(s):  
Satya Narayana Patro ◽  
Khawaja Hassan Haroon ◽  
Khansabegum Tamboli ◽  
Abdulaziz Zafar ◽  
Suhail Hussain ◽  
...  
Keyword(s):  
Medial Temporal Lobe ◽  
Optic Tract ◽  
Internal Capsule ◽  
Cerebral Peduncle ◽  
Anterior Choroidal Artery ◽  
Vessel Occlusion ◽  
External Compression ◽  
Posterior Limb ◽  
Anterior Choroidal ◽  
Choroidal Artery

The anterior choroidal artery (AChA) is a small artery commonly arising from the supraclinoid segment of the internal carotid artery (ICA). The significance of the AChA is related to its strategic supply to various important structures of the brain, such as the optic tract, the posterior limb of the internal capsule, the cerebral peduncle, the lateral geniculate body, medial temporal lobe, medial area of pallidum, and the choroid plexus [<i>J Neurol</i>. 1988;235:387–91]. The AChA syndrome in its complete form consists of the triad of hemiplegia, hemisensory loss, and hemianopia. However, incomplete forms are more frequent in clinical practice [<i>Stroke</i>. 1994;25:837–42]. Isolated infarction in the AChA territory is relatively rare. The presumed pathogenic mechanisms of AChA infarction are cardiac emboli, large-vessel atherosclerosis, dissection of the ICA, small-vessel occlusion, or other determined or undetermined causes [<i>Stroke</i>. 1994;25:837–42 and <i>J Neurol Sci</i>. 2009;281:80–4].

Multiple constrictions of the radial nerve without external compression

2000 ◽  
Vol 25 (1) ◽  
pp. 134-137 ◽  
Author(s):  
Shinichi Yamamoto ◽  
Akira Nagano ◽  
Yoji Mikami ◽  
Yasuhito Tajiri
Keyword(s):  
Radial Nerve ◽  
External Compression

scholarly journals Primary squamous cell carcinoma of the thyroid: a case report

2021 ◽  
Vol 49 (4) ◽  
pp. 030006052110047
Author(s):  
Sixu Xin ◽  
Wei Li ◽  
Ning Yuan ◽  
Chao Shen ◽  
Dongdong Zhang ◽  
...  
Keyword(s):  
Squamous Cell Carcinoma ◽  
Neck Pain ◽  
Cell Carcinoma ◽  
Squamous Cell ◽  
Oral Prednisone ◽  
Thyroid Function Tests ◽  
Primary Squamous Cell Carcinoma ◽  
External Compression ◽  
Laboratory Findings ◽  
Superior Mediastinum

Primary squamous cell carcinoma of the thyroid (PSCCT) is a rare and rapidly progressive malignancy that carries a poor prognosis. PSCCT is easily misdiagnosed as acute thyroiditis or as another thyroid malignancy. We have reported a 76-year-old woman who presented with progressive neck pain for 1 month. Thyroid function tests revealed subclinical thyrotoxicosis. Ultrasound disclosed a solid nodule with calcification in the right thyroid lobe. Laboratory findings included neutrophilic leukocytosis and an elevated erythrocyte sedimentation rate. The patient’s condition was diagnosed as subacute thyroiditis, and she was treated with cefixime and ibuprofen. However, her treatment response was poor. She was then treated with oral prednisone. Her neck pain gradually resolved. The patient subsequently developed dysphagia, choking, dyspnea, and dysphonia with an insidious onset. Further examinations including computed tomography and painless gastroscopy revealed that the volume of the thyroid gland had increased significantly, extending to the anterior superior mediastinum. The trachea and esophagus were stenotic because of external compression. Partial thyroidectomy and tracheotomy were performed under extracorporeal membrane oxygenation. The diagnosis of PSCCT was established via histopathology and immunohistochemistry.

Chimerization of Monitor Flap in a Vascularized Ulnar Nerve Flap Is an Efficient Way for Vascularity Monitoring and the Reinnervation Checkup after Its Transplantation

2021 ◽  
Author(s):  
Lisa Wen-Yu Chen ◽  
Abraham Zavala ◽  
David Chwei-Chin Chuang ◽  
Johnny Chuieng-Yi Lu ◽  
Tommy Nai-Jen Chang
Keyword(s):  
Nerve Injury ◽  
Ulnar Nerve ◽  
Perioperative Complications ◽  
Microvascular Complications ◽  
Demographic Data ◽  
Skin Flap ◽  
Ulnar Artery ◽  
Functional Improvement ◽  
External Compression ◽  
Skin Paddle

Abstract Background Free vascularized ulnar nerve flaps (VUNF) are effective method for long nerve defects reconstruction. However, the monitorization of its microvascular circulation and the nerve regrowth can be challenging since it is usually designed as a buried flap. We designed a skin paddle based on a septocutaneous perforator from the ulnar artery that can be dissected and raised in conjunction with the vascularized ulnar nerve flap, which aims to improve postoperative monitorization to optimizing the clinical results. Methods We retrospectively reviewed 10 cases with long nerve defects who underwent reconstruction using VUNF between June 2018 and June 2019, including eight acute brachial plexus injuries, 1 multiple nerve injury due to a rolling machine accident, and 1 sequalae of nerve injury after arm replantation. All the demographic data, surgical details, outcomes, and perioperative complications were recorded. Results We evaluated 10 male patients, with a mean age of 34 ± 16 years. Cases included 5 antegrade, 4 retrograde, and 1 U-shaped VUNF. All chimeric skin paddles survived, and all of the underlying nerves presented with adequate circulation and functional improvement. There were no intraoperative or microvascular complications. One skin paddle had a transitory postoperative circulation compromise due to external compression (bandage) which resolved spontaneously after pressure release. Conclusion VUNF chimerization of a septocutaneous perforator skin flap is a relatively easy and efficient method for postoperative monitorization of the nerve’s microvascular circulation as well as beneficial for postoperative Tinel’s sign checkup to confirm the success of the nerve coaptation. The outcome is potentially improved.

Positional Hand Pallor and Isolated Epitrochlear Lymphadenitis Secondary to Bartonella henselae Infection.

2021 ◽  
Vol 20 (4) ◽  
pp. 914-917
Author(s):  
Siti Nuradliah Jamil ◽  
Ilham Ameera Ismail ◽  
Siti Fatimah Badlishah Sham ◽  
Norliana Dalila Mohamad Ali
Keyword(s):  
Lymph Node ◽  
Communicable Disease ◽  
Bartonella Henselae ◽  
Medical Science ◽  
Neck Region ◽  
Rare Condition ◽  
Cat Scratch Disease ◽  
Serological Evidence ◽  
External Compression ◽  
Head And Neck Region

Cat scratch disease is a communicable disease caused by the Bartonella henselae bacteria. Regional lymphadenopathy is the hallmark of cat scratch disease and about 75% of lymphadenopathy cases are localized in the head and neck region. An epitrochlear lymphadenopathy is a rare condition at any age and often misdiagnosed as it is not normally palpable. External compression of an enlarged epitrochlear lymph node compromising vascularity was not mentioned in any literature before. We present a case of a 13-year-old girl with right positional ipsilateral hand pallor and epitrochlear lymphadenitis with serological evidence of Bartonella henselae infection. Bangladesh Journal of Medical Science Vol.20(4) 2021 p.914-917

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