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"The aim is to establish the feasibility to image in vivo microscopic dental surface by non-invasive, real-time, en face Reflectance Confocal Microscopy (RCM). Fifteen healthy volunteers referred at the Multidisciplinary Department of Medical-Surgical and Odontostomatological Specialties, Second University of Naples, Naples, Italy, were enrolled. A commercially available hand-held RCM (Vivascope®3000, Lucid, Rochester, NY, USA) was used to image in vivo the dental surface of the upper right and left central incisors of each volunteer. Totally, thirty vestibular surfaces of upper central incisors were imaged in vivo by RCM to preliminary image the dental surface and assess the feasibility of a more extended study on teeth. In vivo RCM was able to image the dental surface within the enamel, at a maximum depth imaging of 300 μm, with images good in quality and the capability to detect enamel structures such as enamel lamellae and enamel damages, such as unevenness and cracks. In conclusion, enamel “optical biopsy”, gained by RCM imaging, revealed to be a non-invasive real-time tool valid to obtain architectural details of the dental surface with no need for extraction or processing the samples. RCM appears to be an optimum auxiliary device for investigating the architectural pattern of superficial enamel, therefore inviting further experiments aimed to define our knowledge about damages after etching treatments or bracket removal and the responsiveness to fluoride seals and the morphology of the tooth/restoration interface. Moreover, this device could also be used to detect relevant diseases like caries, or to assess surface properties to evaluate lesion activity."

"The enamel defects (EDs) may present with a variety of clinical manifestations with increasing severity from the sole appearance of pale discoloration to remarkable structural alterations. EDs are responsible for higher caries receptivity. In vivo reflectance confocal microscopy (RCM) allows to image in vivo at microscopic resolution of the dental surface, thus avoiding the tooth extraction and the sample preparation because of its ability to optically scan living tissues along their depth. Aim of this study is the in vivo assessment at microscopic resolution of dental surfaces affected by EDs without resorting to invasive methods such as teeth extractions, to define histological findings occurring in chromatic and/or structural EDs. For the purpose, 15 children, referring at the Dental Clinic of the Second University of Naples, affected by several degrees of EDs, were enrolled and underwent in vivo RCM imaging to microscopically define the ED confocal features using a commercially available hand-held reflectance confocal microscope with neither injuries nor discomfort. Totally, 29 teeth were imaged. Results demonstrated images good in quality and the capability to detect EDs such as unevenness, grooves, and lack of mineralization according to their clinical degree of disarray. The present in vivo microscopic study on EDs allowed to highlight structural changes in dental enamel at microscopic resolution in real-time and in a non-invasive way, with no need for extraction or processing the samples. Further experiments could define the responsiveness to remineralizing procedures as therapeutic treatments."

"This book focuses on the use and significance of in vivo reflectance confocal microscopy (RCM) for non-invasive high-resolution imaging of the skin. All of the chapters in this hands-on guide are generously illustrated with numerous confocal images and structured in a reader-friendly way. The contents include detailed information on the most relevant and up-to-date aspects of RCM, schematic drawings summarizing and explaining the most important RCM criteria, and a chapter specifically devoted to bridging the gap between dermoscopy, RCM, and histopathology. At the end of each chapter, core messages recapitulate the most pertinent aspects. Reflectance confocal microscopy for skin diseases will be a valuable resource for all physicians involved in the diagnosis and treatment of neoplastic and inflammatory skin diseases."

"Penelitian baru-baru ini yang menggunakan mikroskopi pump-probe pada material Sr$_{1-y}$NbO$_{3+\delta}$ menunjukkan kemampuan optical-switching yang mengarah kepada reduksi reflektansi hingga mendekati 100 %. Pada studi ini, kami mengajukan model sederhana untuk menjelaskan fenomena ini. Kami berhipotesis bahwa reduksi reflektansi ini disebabkan oleh efek korelasi yang muncul akibat interaksi elektron-elektron seiring dengan berkurangnya pengisian elektron pada pita konduksi karena tereksitasi ke pita yang lebih tinggi sepanjang waktu pump-ON. Di sini, kami memodelkan sistem material menggunakan model Hubbard satu-dimensi. Model ini kemudian diselesaikan dengan menggunakan metode fungsi Green dalam teori iterasi perturbasi termodifikasi (MIPT) untuk mempertahankan ketergantungan terhadap frekuensi pada self-energy. Hal ini penting karena self-energy ini memanifestasi hamburan elektron-elektron yang merupakan proses dinamis. Fungsi Green self-consistent yang diperoleh kemudian digunakan untuk menghitung fungsi respon optis dan reflektansi sebagai fungsi frekuensi foton. Terakhir, kami menampilkan nilai reflektansi pada frekuensi probe sebagai fungsi waktu dan membandingkannya dengan data eksperimen.

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A recent experimental study of pump-probe microscopy on material Sr$_{1-y}$NbO$_{3+\delta}$ shows an optical switching that leads to the reflectance reduction up to nearly 100 %. In this study, we propose a simple model to explain this phenomenon. We hypothesize that the reflectance reduction is caused by correlation effects arising from the electron-electron interaction accompanying the decrease of electron filling in conduction band as the electrons are excited to the higher band during pump-ON period. Here, we model the system using the one-dimensional Hubbard model. We solve this model using Green function method within modified iterated perturbation theory (MIPT) to retain the frequency dependence in the self energy. This is important since the self energy manifests the electron-electron scattering which is a dynamical process. The obtained self-consistent Green function is then used further to calculate the optical response function and the reflectance as a function of photon frequency. Finally, we plot the reflectance value at the probe frequency as a function of time and compare it to the experimental data."

"This book presents the recent advances that have been made using mathematical methods to resolve problems in microscopy. With improvements in hardware-based aberration software significantly expanding the nanoscale imaging capabilities of scanning transmission electron microscopes (STEM), these mathematical models can replace some labor intensive procedures used to operate and maintain STEMs. This book, will also cover such relevant concepts as superresolution techniques, special denoising methods, application of mathematical/statistical learning theory, and compressed sensing."