University of Nevada, Reno

About: University of Nevada, Reno is a education organization based out in Reno, Nevada, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 13561 authors who have published 28217 publications receiving 882002 citations. The organization is also known as: University of Nevada & Nevada State University.

High-grade dysplasia in the columnar-lined esophagus.

Abstract: Abnormal columnar lining of the esophagus is a well-recognized premalignant condition. The management of patients with high-grade dysplasia without evidence of carcinoma remains controversial. Esophagectomy is proposed by some investigators, whereas others favor follow-up endoscopy and biopsy until microinvasive malignancy is documented. We reviewed our experience with nine patients referred with high-grade dysplasia on endoscopic biopsies without evidence of carcinoma. Eight patients had the columnar lining extending orad from the cardia, and one patient had heterotopic columnar epithelium in the cervical esophagus. All were white men ranging in age from 19 to 76 years (median: 47 years). Eight patients underwent esophagectomy with colon interposition. A sleeve resection of the cervical esophagus was done in one patient. Multifocal carcinoma was found in three patients, all of whom had severe dysplastic changes throughout the columnar lining. The patient with heterotopic columnar epithelium had microinvasive carcinoma. All four patients with carcinoma had negative nodes and are long-term survivors. No carcinoma was found in the resected specimens of the remaining five patients. High-grade dysplasia is an important marker of malignancy in patients with a columnar-lined esophagus. Esophagectomy is indicated in suitable candidates since carcinoma was found in 45% of our patients.

Rain or Snow: Hydrologic Processes, Observations, Prediction, and Research Needs

Abstract: . The phase of precipitation when it reaches the ground is a first-order driver of hydrologic processes in a watershed. The presence of snow, rain, or mixed-phase precipitation affects the initial and boundary conditions that drive hydrological models. Despite their foundational importance to terrestrial hydrology, typical phase partitioning methods (PPMs) specify the phase based on near-surface air temperature only. Our review conveys the diversity of tools available for PPMs in hydrological modeling and the advancements needed to improve predictions in complex terrain with large spatiotemporal variations in precipitation phase. Initially, we review the processes and physics that control precipitation phase as relevant to hydrologists, focusing on the importance of processes occurring aloft. There is a wide range of options for field observations of precipitation phase, but there is a lack of a robust observation networks in complex terrain. New remote sensing observations have the potential to increase PPM fidelity, but generally require assumptions typical of other PPMs and field validation before they are operational. We review common PPMs and find that accuracy is generally increased at finer measurement intervals and by including humidity information. One important tool for PPM development is atmospheric modeling, which includes microphysical schemes that have not been effectively linked to hydrological models or validated against near-surface precipitation-phase observations. The review concludes by describing key research gaps and recommendations to improve PPMs, including better incorporation of atmospheric information, improved validation datasets, and regional-scale gridded data products. Two key points emerge from this synthesis for the hydrologic community: (1) current PPMs are too simple to capture important processes and are not well validated for most locations, (2) lack of sophisticated PPMs increases the uncertainty in estimation of hydrological sensitivity to changes in precipitation phase at local to regional scales. The advancement of PPMs is a critical research frontier in hydrology that requires scientific cooperation between hydrological and atmospheric modelers and field scientists.

Regulation of ion channels in smooth muscles by calcium.

Abstract: Intracellular Ca2+ concentration ([Ca2+]i) plays a central role in regulating tone and contractility of smooth muscle cells. In contrast to the “classic” model of electromechanical coupling where m...