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Evidence has been mixed regarding the effect of topical vancomycin (VCM) powder in reducing surgical site infection (SSI). To clarify the effect of topical VCM powder for the prevention of SSI in major orthopaedic surgeries. The MEDLINE, Embase, CENTRAL, ICTRP, and ClinicalTrials.gov databases were searched from their inception to September 25th, 2023. Randomized controlled trials comparing topical VCM powder and controls for the prevention of SSI in major orthopaedic surgeries were included. Two reviewers independently screened the title and abstract and extracted relevant data, followed by the assessment of the risk of bias and the certainty of the evidence. Main outcome measures were overall SSI, reoperation, and adverse events. Summary results were obtained using random-effects meta-analysis. Trial sequential analysis (TSA) was performed. Eight randomized controlled trials yielded data on 4307 participants. VCM powder showed no difference in reducing overall SSI. The cumulative number of patients did not exceed the required information size of 19,233 in our TSA, and the Z -curves did not cross the trial sequential monitoring or futility boundary, suggesting an inconclusive result of the meta-analysis. No difference was found for reoperation. Among SSIs, VCM powder showed a statistically significant difference in reducing Gram-positive cocci SSI. However, the certainty of this evidence was very low. This systematic review and meta-analysis suggests inconclusive results regarding the effect of VCM powder in reducing SSI in major orthopaedic surgeries. Further trials using rigorous methodologies are required to elucidate the effect of this intervention. [ABSTRACT FROM AUTHOR]

Abstract: In the chemical–mechanical polishing (CMP) of semiconductor structures, such defects as micro- and nano-scale scratches are frequently produced on the surfaces being polished. Recent research shows that not only agglomerated abrasives but the softer pad asperities in frictional contact also scratch the relatively hard surfaces. Accordingly, pad scratching is modeled based on the topography and mechanical properties of pad asperities. Asperity radius, R a , and the standard deviation of asperity heights, σ z , are identified as the key topographical parameters. The theoretical models and experimental results show that pad scratching in CMP can be mitigated by increasing R a /σ z . [Copyright &y& Elsevier]

Abstract: In the fabrication of micro- and nano-scale semiconductor devices and electromechanical systems, the chemical–mechanical polishing (CMP) process is extensively employed. During the CMP process, undesirable scratches are produced on metal-interconnect and low-k-dielectric surfaces by the softer pad asperities. This paper presents contact mechanics models for the initiation of scratching in terms of the pad asperity geometry, the interfacial friction, and the mechanical properties of materials. Results of dry, wet and lubricated experiments on Cu coatings qualitatively validate the theoretical models. To mitigate scratching by pad asperities during CMP, the developed models suggest that the friction coefficient be kept below 0.2. [Copyright &y& Elsevier]

Abstract: During chemical–mechanical polishing (CMP) in the fabrication of advanced semiconductor devices, undesirable nano-scale scratches are produced, especially in the presence of low-k dielectrics. In this paper, the lower- and upper-bound loads for scratching are estimated by contact mechanics models and are validated by AFM experiments. Additionally, the width and depth of scratches are related to such process parameters as: particle size, abrasive volume fraction, mechanical and geometric properties of the pad and surface coatings, and polishing pressure. The upper-limit for scratch width is found to be a function of the particle size and the hardnesses of the coatings and the pad. In Cu CMP this limit is about one-fifth of the abrasive diameter. [Copyright &y& Elsevier]

Abstract: Objective: Churg–Strauss syndrome (CSS) is known as autoimmune vasculitis with peripheral eosinophilia after bronchial asthma and rarely has otological findings. We present a case of CSS with refractory otitis media and discuss the relationship between otological symptoms of CSS and eosinophilic otitis media. Case report: A 60-year-old woman had suffered from recurrent sinusitis for 8 years, and also otitis media with effusion for 4 months. Eruption with peripheral eosinophilia was found in the lower legs; therefore, she was diagnosed with CSS. She was treated with systemic administration of predonisolone, intratympanic injection of betamethasone, and betamethasone nasal spray; thereafter, eosinophilia, otitis media and sinusitis rapidly improved. Conclusion: The features of eosinophilic otitis media are similar to the otological symptoms of CSS. It should be considered whether patients with eosinophilic otitis media have early phase CSS. [Copyright &y& Elsevier]