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Lomas formations or "fog oases" are islands of vegetation in the desert belt of the west coast of South America, with a unique vegetation composition among the world's deserts. However, plant diversity and conservation studies have long been neglected, and there exists a severe gap in plant DNA sequence information. To address the lack of DNA information, we conducted field collections and laboratory DNA sequencing to establish a DNA barcode reference library of Lomas plants from Peru. This database provides 1,207 plant specimens and 3,129 DNA barcodes data corresponding with collections from 16 Lomas locations in Peru, during 2017 and 2018. This database will facilitate both rapid species identification and basic studies on plant diversity, thereby enhancing our understanding of Lomas flora's composition and temporal variation, and providing valuable resources for conserving plant diversity and maintaining the stability of the fragile Lomas ecosystems., (© 2023. The Author(s).)

The case analysis of five patients with post-ampullary adenocarcinoma of the duodenum showed this to be a tumor which favors local extension into surrounding organs, instead of lymphatic or hepatic metastasis. This justifies and aggressive resectional approach to treatment, pancreaticoduodenectomy being the basic operation to be applied. Proximity to the superior mesenteric vessels involving them in four out of five of our tumors, is the major anatomic limiting factor. Leaving vascular control for the end of the excision and perfusing them to maintain viability of the gut until a comfortable vascular anastomosis can be constructed, should solve the problem. Misdiagnosis proved to be a prominent source of error, causing delays and inappropriate therapy. The Cancer Registry of Puerto Rico has documented an incidence of carcinoma of the duodenum similar to that of the ampulla of Vater. This fact demands the same care in the conduct of diagnostic procedures of the distal duodenum as is customary in the visualization of the ampulla.