Coulomb Explosion and Thermal Spikes

A fast ion penetrating a solid creates a track of excitations. This can produce displacements seen as an etched track, a process initially used to detect energetic particles but now used to alter materials. From the seminal papers by Fleischer et al. [Phys. Rev. 156, 353 (1967)] to the present [C. Trautmann, S. Klaumunzer and H. Trinkaus, Phys. Rev. Lett. 85, 3648 (2000)], `Coulomb explosion' and thermal spike models are treated as conflicting models for describing ion track effects. Here molecular dynamics simulations of electronic-sputtering, a surface manifestation of ion track formation, show that `Coulomb explosion' produces a `heat' spike so that these are early and late aspects of the same process. Therefore, differences in scaling are due to the use of incomplete spike models.Comment: Submitted to PRL. 4 pages, 3 figures. For related movies see: http://dirac.ms.virginia.edu/~emb3t/coulomb/coulomb.html PACS added in new versio

Fabrication and characterization of thin, self‐supporting germanium single crystals

Thin Gesingle crystals (≤1 μm) up to 4 mm in diameter have been fabricated from epitaxialGefilmsgrown by atmospheric pressurechemical vapor deposition on Si(100) wafers. The thin Ge windows are formed by chemically etching away both the Si substrate and the region of the Gefilm near the interface that contains misfit dislocations associated with heteroepitaxialgrowth and relaxation of the Gefilms. The resulting Gefilms are comparable in crystalline quality to bulk Ge wafers, as indicated by ion channeling studies

Staphylococcal Panton-Valentine Leucocidin as a Major Virulence Factor Associated to Furuncles

Panton-Valentine Leucocidin (PVL), one of the β-barrel pore-forming staphylococcal leucotoxins, is known to be associated to furuncles and some severe community pneumonia. However, it is still uncertain how many other virulence factors are also associated to furuncles and what the risk factors of furuncles are in immuno-compromised status of patients, especially the HIV (+) patients. In this paper, we use antigen immunoprecipitation and multiplex PCR approach to determine the presence of 19 toxins, 8 adhesion factors and the PFGE profiles associated to furuncles in three independent patient study groups of S. aureus (SA) isolates collected from the Cayenne General Hospital (French Guiana). The patient groups were made of: 16 isolates from HIV (−) patients, 9 from HIV (+) patients suffering from furuncles, and 30 control isolates from patients with diverse secondary infected dermatitis. Our data reveals that the majority (96%) of SA strains isolated from HIV patient-derived furuncles significantly produced PVL (p<10−7), whereas only 10% of SA strains produced this toxin in secondary infected dermatosis. A high prevalence of LukE-LukD-producing isolates (56 to 78%) was recorded in patient groups. Genes encoding clumping factor B, collagen- and laminin-binding proteins (clfB, cna, lbp, respectively) were markedly frequent (30 to 55%), without being associated to a specific group. Pulse field gel electrophoresis evidenced 24 overall pulsotypes, whereas the 25 PVL-producing isolates were distributed into 15 non clonal fingerprints. These pulsotypes were not specific PVL-producing isolates. PVL appears to be the major virulence factor associated to furuncles in Europe and in South America regardless of the immune status of the HIV patients

Rhinitis in the geriatric population

The current geriatric population in the United States accounts for approximately 12% of the total population and is projected to reach nearly 20% (71.5 million people) by 2030[1]. With this expansion of the number of older adults, physicians will face the common complaint of rhinitis with increasing frequency. Nasal symptoms pose a significant burden on the health of older people and require attention to improve quality of life. Several mechanisms likely underlie the pathogenesis of rhinitis in these patients, including inflammatory conditions and the influence of aging on nasal physiology, with the potential for interaction between the two. Various treatments have been proposed to manage this condition; however, more work is needed to enhance our understanding of the pathophysiology of the various forms of geriatric rhinitis and to develop more effective therapies for this important patient population

International Consensus Statement on Rhinology and Allergy: Rhinosinusitis

Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS

Endoscopic management of frontal sinus osteomas revisited

Background: Recent articles have published guidelines regarding the role of endoscopic surgery in the removal of frontal sinus osteomas. These guidelines recommend the endoscopic approach for small osteomas but recommend an osteoplastic flap for larger tumors. This study presents a series of endoscopically resected tumors both large and small. Methods: Retrospective chart reviews were performed. Charts were reviewed of all patients who underwent surgical resection of a frontal sinus osteoma from 1998 to 2008. Sinus CT scans were reviewed and each tumor was staged according to Kennedy's grading system proposed in 2005. Results: Twenty-three patients, 8 with a grade IV tumor, 6 with a grade III tumor, and the remaining with a grade I or II tumor, underwent endoscopic resection of a frontal sinus osteoma. In 15 patients a modified Lothrop procedure was performed for tumor removal. In addition, a blepharoplasty incision was used in one patient for removal of a large orbital extension of the tumor and another underwent an enlarged frontal sinus trephine performed via a browline incision. In the remaining patients a frontal sinusotomy with minitrephination provided enough access for tumor removal. Over an average follow-up of 36 months no recurrences were noted. Symptoms improved in all but one patient. There were no postoperative complications. Conclusion: Endoscopic resection of both large and small frontal sinus osteomas is feasible. In this article we have shown successful removal of large osteomas that fill the entire frontal sinus with the modified Lothrop procedure.Seiberling, Kristin; Floreani, Steve; Robinson, Simon; Wormald, Peter-Joh

Surgical outcomes of endoscopic management of adenocarcinoma of the sinonasal cavity

Objective: To report the surgical outcomes of endoscopic resection of adenocarcinomas of the Sinonasal cavity. Methods: Retrospective chart review of patients presenting with adenocarcinoma of the anterior skull base between 1998-2008. All patients who underwent wholly endoscopic resection were included in the study. Results: Twelve patients presented with adenocarcinoma involving the sino-nasal cavity. At diagnosis 6 patients were staged as a T2, 5 as a T3 and one as a T4. All of the patients had successful removal of the tumour entirely endoscopically. Three patients recurred: 2 locally and 1 with distant metastases. Overall, 11 patients are alive and free of disease and 1 patient dead of disease. We found an overall disease free survival rate and overall survival rate of 91.6%. The follow-up period ranged from 10 to 96 months with a median of 30 months. Conclusion: Endoscopic management of adenocarcinoma of the sino-nasal cavity can be a viable treatment option to craniofacial resection. With the advancement in endoscopic equipment and surgeon skill, larger tumours may be managed wholly endoscopically.C. Jardeleza, K. Seiberling, S. Floreani, and P.J. Wormaldhttp://www.rhinologyjournal.com/article/article_list.php?mgzn_id=15

Temporal Lobe Abscess in a Patient with Isolated Sphenoiditis

A 74-year-old immunocompetent man admitted for severe retro-orbital headache was diagnosed with isolated sphenoiditis. At the time of scheduled surgery, the patient was mildly obtunded, and a head CT revealed a temporal lobe abscess. The patient underwent a left temporal craniectomy and a bilateral endoscopic sphenoid sinusotomy, which revealed gross fungal debris. The patient made a full recovery with resolution of abscess and sinus findings. Suspicion for intracranial infection should be raised in any sinus patient with neurological changes. Early diagnosis with imaging studies is extremely important for surgical drainage before permanent neurological sequelae

Office CO2 Laser Turbinoplasty

We conducted a prospective study of office carbon dioxide (CO2) laser turbinoplasty as a treatment for symptoms related to turbinate dysfunction in 58 patients. All patients completed surveys before and 1 month after treatment, and 23 patients completed longer-term follow-up surveys 8 to 24 months postoperatively. The 1-month postoperative assessments demonstrated a trend toward symptom improvement, as many patients reported a decrease in their use of pretreatment medications. Long-term benefit was achieved in 70% of patients. Ten patients underwent pre- and post-treatment biopsies, and histologic evaluation demonstrated minimal tissue alteration following treatment, alleviating concerns of physiological and functional compromise. We conclude that office-based CO2 laser turbinoplasty is a useful tool for the treatment of disorders related to turbinate dysfunction. We describe one clinician's method of performing office CO2 laser turbinoplasty, and we report his experience and findings. </jats:p