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Gomez Montoya posted an update 1 day, 15 hours ago
We present an experimental and theoretical analysis of the formation of nanovoids within Si microcrystals epitaxially grown on Si patterned substrates. The growth conditions leading to the nucleation of nanovoids have been highlighted, and the roles played by the deposition rate, substrate temperature, and substrate pattern geometry are identified. By combining various scanning and transmission electron microscopy techniques, it has been possible to link the appearance pits of a few hundred nanometer width at the microcrystal surface with the formation of nanovoids within the crystal volume. A phase-field model, including surface diffusion and the flux of incoming material with shadowing effects, reproduces the qualitative features of the nanovoid formation thereby opening new perspectives for the bottom-up fabrication of 3D semiconductors microstructures.Background Discoid medial meniscus is an extremely rare congenital anatomic variant with an estimated incidence of 0.12%. Arthroscopic meniscal saucerization and repair are reserved for symptomatic tears only. We present a case of discoid medial meniscus tear, outline the surgical arthroscopic technique used for treatment, and compare several surgical approaches. Case Report An 18-year-old male presented with left knee pain and mechanical symptoms present for 2 years. Physical examination showed stability to both varus and valgus stresses with absence of locking or catching on McMurray testing. Magnetic resonance imaging confirmed discoid medial meniscus with a horizontal oblique tear of the posterior horn. The patient underwent saucerization of the left discoid medial meniscus and medial meniscus repair. Conclusion Discoid medial meniscus predisposes individuals to meniscal tears that often require operative management. Careful consideration of surgical approach can help to optimize patient outcomes while minimizing the risk of iatrogenic injury.Background Patients who are diagnosed with dextrocardia, a rare congenital heart condition in which the heart points toward the right side of the chest, need their specific situs classification (eg, solitus, inversus, ambiguus) ascertained to optimize their care and outcomes. In this report, we discuss the perioperative anesthetic management of a patient presenting with dextrocardia. Atamparib Case Report A 44-year-old African American female with a history of hypertension, hyperlipidemia, gastroesophageal reflux disease, and diabetes mellitus type 2 was admitted for shortness of breath, dyspnea on exertion, orthopnea, and paroxysmal nocturnal dyspnea. The patient had been diagnosed with dextrocardia in 2003 at an outside hospital and was asymptomatic prior to this presentation. Chest x-ray revealed bilateral perihilar vascular congestion with bibasilar atelectasis and suspected small bilateral pleural effusions consistent with new-onset congestive heart failure. Preoperative 2-dimensional transthoracic echocardiography revealed an ostium secundum-type atrial septal defect (ASD) with mild left-to-right atrial shunting. The patient’s ASD was repaired using a pericardial patch. Conclusion The anesthetic management of patients presenting with dextrocardia is complex. Preoperative cardiac transthoracic echocardiography can identify cardiac lesions or aberrant anatomy associated with dextrocardia. Proper placement of electrocardiogram electrodes is necessary to avoid false-positive results for perioperative ischemia. Central line access must be adjusted to anatomic variations. Clinicians should have high suspicion for associated pulmonary hypertension and should limit sedatives preoperatively to minimize the cardiovascular effects of hypoxia and/or hypercarbia on the pulmonary vasculature. Finally, high clinical suspicion for respiratory complications should be maintained, as dextrocardia has been associated with respiratory complications secondary to primary ciliary dyskinesia in approximately 25% of patients.Background Duplication of the vas deferens, a rare congenital anomaly of the pelvic anatomy, is often an incidental finding during surgeries involving the spermatic cord, such as inguinal hernia repair, varicocelectomy, orchidopexy, and vasectomy. Case Report A 25-year-old male presented to our surgical outpatient clinic with bilateral swelling in the inguinal region. A diagnosis of bilateral inguinal hernia was established. While performing spermatic cord dissection during hernioplasty, a duplicated vas deferens was revealed within the left spermatic cord. Doppler ultrasonography confirmed the absence of waveforms in both vasa deferentia, differentiating them from adjacent vessels. The hernia repair was performed without complications. Conclusion Our case highlights the importance of radiologists’ and surgeons’ ability to recognize a duplicated vas deferens to avoid possible iatrogenic injury.Background Visceral artery aneurysms and pseudoaneurysms are uncommon phenomena with a high mortality rate in cases of rupture. These rare vascular pathologies are usually asymptomatic and are therefore generally discovered incidentally on computed tomography or magnetic resonance imaging examination. Current therapeutic options have trended toward a minimally invasive approach because of evolving endovascular treatment options, with open operations typically reserved for cases of intraabdominal hemorrhage. Case Report We describe a case of gastroduodenal artery pseudoaneurysm manifesting as obstructive jaundice and pancreatitis because of extrahepatic compression of the common bile duct and pancreatic duct by mass effect. Open repair was ultimately required secondary to arterial anatomy that was not amenable to any endovascular treatment approach. Conclusion While endovascular options are the preferred treatment modality for visceral artery aneurysms and pseudo-aneurysms, some cases require definitive open repair for a variety of reasons, including unsuitable anatomy.Background Multiple closed spontaneous pulley ruptures are rare injuries and require surgical reconstruction to prevent functional deficits. Pulley rupture combined with avulsion of the flexor digitorum superficialis (FDS) tendon is an even more uncommon occurrence. Case Report We describe a closed traumatic annular 2 (A2) through annular 4 (A4) pulley rupture with avulsion of the FDS tendon. This uniquely associated pathology was treated with a complex surgical reconstruction that corrected flexion contracture and tendon bowstringing in the left long finger. The desired outcome was achieved through A2 and A4 pulley reconstruction using an autologous palmaris longus tendon graft with FDS tendon excision and proximal interphalangeal joint capsulotomy. Conclusion Multiple pulley rupture is not commonly combined with FDS avulsion, and treatment of this injury requires careful surgical planning based on pulley biomechanics to maximize postoperative function.