Dipolar and scalar 3^3He and 129^{129}Xe frequency shifts in mm-sized cells

We describe a $^{3}$He-$^{129}$Xe comagnetometer operating in stemless anodically bonded cells with a 6 mm$^3$ volume and a $^{129}$Xe spin coherence time of 300 sec. We use a $^{87}$Rb pulse-train magnetometer with co-linear pump and probe beams to study the nuclear spin frequency shifts caused by spin polarization of $^{3}$He. By systematically varying the cell geometry in a batch cell fabrication process we can separately measure the cell shape dependent and independent frequency shifts. We find that a certain aspect ratio of the cylindrical cell can cancel the effects of $^3$He magnetization that limit the stability of vapor-cell comagnetometers. Using this control we also observe for the first time a scalar $^{3}$He-$^{129}$Xe collisional frequency shift characterized by an enhancement factor $\kappa_{\text{HeXe}} = -0.011\pm0.001$.Comment: 4 pages, 4 figure

Isolation and primary cultures of human intrahepatic bile ductular epithelium

A technique for the isolation of human intrahepatic bile ductular epithelium, and the establishment of primary cultures using a serum- and growth-factor-supplemented medium combined with a connective tissue substrata is described. Initial cell isolates and monolayer cultures display phenotypic characteristics of biliary epithelial cells (low molecular weight prekeratin positive; albumin, alphafetoprotein, and Factor VIII-related antigen negative). Ultrastructural features of the cultured cells show cell polarization with surface microvilli, numerous interepithelial junctional complexes and cytoplasmic intermediate prekeratin filaments. © 1988 Tissue Culture Association, Inc

AN UPDATED DISTRIBUTION MAP FOR THE LOWER COLORADO RIVER VALLEY POPULATION OF GREATER SANDHILL CRANES

The U.S. Fish and Wildlife Service (USFWS) recognizes 6 migratory populations of sandhill cranes (Grus canadensis) in the United States, 4 of which occur in or west of the Rocky Mountains. Traditionally the Lower Colorado River Valley Population (LCRVP; greater sandhill crane [G. c. tabida]) was thought to be distributed across the Imperial (California) and Lower Colorado River (Arizona) Valleys, southward into Mexico via the Colorado River delta in winter and northeastern Nevada (Elko and White Pine Counties) during summer. Conservation and management concern exists over known distribution based on winter and summer surveys because discrepancies exist between the number of individuals counted on winter and summer termini. In 2014 the USFWS initiated a mark-recapture program on the LCRVP to aid in the development of long-term management of this least abundant greater sandhill crane population. The objective of this paper is to update the known distribution of the LCRVP from greater sandhill cranes by using platform transmitter terminals (PTTs). We captured 44 individual greater sandhill cranes and equipped 22 with PTTs on the wintering and summering grounds in the Imperial and Lower Colorado River Valleys and west-central Idaho, 2014-2015. Our updated distribution map from 18 of 22 PTT-tagged individuals identified several new summer locations extending north and west into west-central Idaho and numerous new migratory locations extending east into Utah. We also confirmed winter locations on the Gila River southwest of Phoenix, Arizona. The extent of the distribution of the LCRVP extends farther north and east than previously expected and, most importantly, overlaps with areas commonly affiliated with the Central Valley and Rocky Mountain Populations in the Intermountain West

The cost of a single concussion in American high school football: A retrospective cohort study

Aim: The potential financial burden of American football-related concussions (FRC) is unknown. Our objective was to describe the healthcare costs associated with an FRC and determine factors associated with increased costs. Methodology/results: A retrospective cohort study of concussed high school football players presenting between November 2017 and March 2020 was undertaken; 144 male high school football players were included. Total costs were about $115,000, for an average direct healthcare cost of$800.10/concussion. Visiting the emergency department (β = 502.29, 95% CI: 105.79-898.61; p = 0.01), the initial post-concussion symptom scale score (β = 0.39, 95% CI: 0.11-0.66; p = 0.01) and a post-concussion syndrome diagnosis (β = 670.37, 95% CI: 98.96-1241.79; p = 0.02) were each independently associated with total costs. Conclusion: A granular understanding of cost-driving factors associated with FRC is the first step in understanding the cost-effectiveness of prevention and treatment methods

Pathophysiology of acute experimental pancreatitis: Lessons from genetically engineered animal models and new molecular approaches

The incidence of acute pancreatitis is growing and worldwide population-based studies report a doubling or tripling since the 1970s. 25% of acute pancreatitis are severe and associated with histological changes of necrotizing pancreatitis. There is still no specific medical treatment for acute pancreatitis. The average mortality resides around 10%. In order to develop new specific medical treatment strategies for acute pancreatitis, a better understanding of the pathophysiology during the onset of acute pancreatitis is necessary. Since it is difficult to study the early acinar events in human pancreatitis, several animal models of acute pancreatitis have been developed. By this, it is hoped that clues into human pathophysiology become possible. In the last decade, while employing molecular biology techniques, a major progress has been made. The genome of the mouse was recently sequenced. Various strategies are possible to prove a causal effect of a single gene or protein, using either gain-of-function (i.e., overexpression of the protein of interest) or loss-of-function studies (i.e., genetic deletion of the gene of interest). The availability of transgenic mouse models and gene deletion studies has clearly increased our knowledge about the pathophysiology of acute pancreatitis and enables us to study and confirm in vitro findings in animal models. In addition, transgenic models with specific genetic deletion or overexpression of genes help in understanding the role of one specific protein in a cascade of inflammatory processes such as pancreatitis where different proteins interact and co-react. This review summarizes the recent progress in this field. Copyright (c) 2005 S. Karger AG, Basel

Mouse model of liver ischemia and reperfusion injury: method for studying reactive oxygen and nitrogen metabolites in vivo

The mouse model of liver ischemia and reperfusion injury has proven to be valuable for our understanding of the role that reactive oxygen and nitrogen metabolites play in postischemic tissue injury. This methods paper provides a detailed protocol for inducing partial liver ischemia followed by reperfusion. Liver ischemia is induced in anesthetized mice by cross-clamping the hepatic artery and portal vein for varying lengths of time resulting in deprivation of blood flow to approximately of 70% of the liver. Restoration of blood flow to the ischemic lobes enhances superoxide production concomitant with a rapid and marked decrease in the bioavailability of nitric oxide resulting in alterations in the redox state of the liver in favor of a more oxidative environment. This hepatocellular oxidative stress induces the activation of oxidant-sensitive transcription factors followed by the upregulation of pro-inflammatory cytokines and mediators that ultimately lead to liver injury. This model can be induced in any strain or sex of mouse and requires 1-2 months of practice to become proficient in the surgery and animal manipulation. The role of different reactive metabolites of oxygen and nitrogen may be evaluated using genetically-engineered mice as well as selective molecular, cellular and/or pharmacological agents