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Symmetry is one of the cornerstones of modern physics and has profound implications in different areas. In symmetry-protected topological systems, symmetries are responsible for protecting surface states, which are at the heart of the fascinating properties exhibited by these materials. When the symmetry protecting the edge mode is broken, the topological phase becomes trivial. By engineering losses that break the symmetry protecting a topological Hermitian phase, we show that a new genuinely non-Hermitian symmetry emerges, which protects and selects one of the boundary modes: the topological monomode. Moreover, the topology of the non-Hermitian system can be characterized by an effective Hermitian Hamiltonian in a higher dimension. To corroborate the theory, we experimentally investigated the non-Hermitian 1D and 2D SSH models using photonic lattices and observed dynamically generated monomodes in both cases. We classify the systems in terms of the (non-Hermitian) symmetries that are present and calculate the corresponding topological invariants., Comment: 24 pages, 17 figures

Neuroblastoma is the most common extracranial solid tumor in children, often manifests in the retroperitoneal region. We present a case of a 3-year-old boy with no previous medical history, presented for abdominal distension. Physical examination revealed a distinct, mobile, solid mass situated in the left lumbar region. Abdominal magnetic resonance imaging displayed a well delimited, well-encapsulated mass attached to the tail of the pancreas. Urinary catecholamine metabolite levels were negative. Surgical exploration revealed that the tumor was primitively related to the left adrenal gland, and a complete resection was performed. The postoperative recovery was uncomplicated. NMYC oncogene was non-amplified., Competing Interests: The authors declare no conflicts of interest regarding the publication of this article., (© 2023 The Authors.)

Introduction: Pleuropulmonary blastoma (PPB) is rare, representing 0.3 % of all pediatric cancers. PPB is classified into three subtypes and may progress from type I to types II and III, with a worse prognosis. Given its rarity, the diagnosis is frequently challenging., Case Presentation: We report an occurrence of PPB in a 3-year-old girl, who presented recurrent pneumopathy. Imaging investigations revealed a large solid lesion in the left hemithorax. Biopsy followed by histological analysis suggested rhabdomyosarcoma. The patient received neoadjuvant chemotherapy before proceeding to complete tumor excision. Surgical exploration revealed that the tumor was primitively related to parietal pleura and lower lobe of left lung. Histopathology of the tumor retained a definitive diagnosis of PPB type II. Postoperative course was uneventful, and a cerebral MRI ruled out brain metastasis. Adjuvant chemotherapy was administered., Discussion: Clinical expression of PPB is nonspecific and variable. It ranges from a dry cough to respiratory distress. Standard radiography is the first examination to perform and CT is the gold standard for characterization thoracic masses. Surgery and chemotherapy are the pillars of treatment. Indications depend on the tumor type, its extent and its resectability., Conclusion: PPB is an aggressive tumor that occurs only in children. Due to the rarity of PPB, evidence on optimal treatment is still insufficient. Careful follow-up is necessary searching for local recurrence or metastasis., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest regarding the publication of this article., (Copyright © 2023. Published by Elsevier Ltd.)