X-ray-Sensitive Doped CaF-Based MRI Contrast Agents for Local Radiation Dose Measurement.

Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose.

Magnetic properties of γ-FeOnanoparticles in a porous SiOshell for drug delivery.

A method is presented for synthesizing core-shell nanoparticles with a magnetic core and a porous shell suitable for drug delivery and other medical applications. The core contains multiple $\gamma$-Fe$_2$O$_3$ nanoparticles ($\sim$15~nm) enclosed in a SiO$_2$ ($\sim$100-200~nm) matrix using either methyl (denoted TMOS-$\gamma$-Fe$_2$O$_3$) or ethyl (TEOS-$\gamma$-Fe$_2$O$_3$) template groups. Low-temperature M{\"o}ssbauer spectroscopy showed that the magnetic nanoparticles have the maghemite structure, $\gamma$-Fe$_2$O$_3$, with all the vacancies in the octahedral sites.

Characterization of Luminescent Materials with Eu Mössbauer Spectroscopy.

The application of Mössbauer spectroscopy to luminescent materials is described. Many solids doped with europium are luminescent, i.e.

Topotactic Fluorine Insertion into the Channels of FeSbO-Related Materials.

This paper discusses the fluorination characteristics of phases related to FeSbO, by reporting the results of a detailed study of MgFeSbO and CoFeSbO. Reaction with fluorine gas at low temperatures (typically 230 °C) results in topotactic insertion of fluorine into the channels, which are an inherent feature of the structure. Neutron powder diffraction and solid state NMR studies show that the interstitial fluoride ions are bonded to antimony within the channel walls to form Sb-F-Sb bridges.

Oxygen Insertion Reactions within the One-Dimensional Channels of Phases Related to FeSbO.

The structure of the mineral schafarzikite, FeSbO, has one-dimensional channels with walls comprising Sb cations; the channels are separated by edge-linked FeO octahedra that form infinite chains parallel to the channels. Although this structure provides interest with respect to the magnetic and electrical properties associated with the chains and the possibility of chemistry that could occur within the channels, materials in this structural class have received very little attention. Here we show, for the first time, that heating selected phases in oxygen-rich atmospheres can result in relatively large oxygen uptakes (up to ∼2% by mass) at low temperatures (ca.

Streamlining Throughput with the Implementation of a CT Coordinator.

Imaging departments today are challenged with streamlining processes to keep up with advancements in healthcare, the increasing complexity of imaging studies and procedures, and bundling of charges for services rendered. Ordering providers are often required to get insurance pre-authorizations for imaging orders, and what is pre-authorized must be the study/procedure performed or reimbursement is not guaranteed. Insurance companies have inhibited radiologists from providing optimal service by placing restrictions on changing orders per radiologist protocol to best meet the individual needs of each patient.

The magnetic and crystal structures of Sr1-δFeO2-xFx, a new oxyfluoride.

A new quasi-two-dimensional oxyfluoride, Sr1-δFeO2-xFx, has been successfully synthesized by combining topotactic fluoridation and CaH2 reduction. The introduction of F through this synthesis provides a new route to introducing charge carriers into the square layered lattice through the formation of Fe(1+) ions. While the average crystal symmetry and magnetic structure remain the same as in the parent compound, the addition of F results in an enhanced buckling of the Fe(O/F)2 square plaquettes that is most likely topologically driven.

The reaction mechanism of FeSb(2) as anode for sodium-ion batteries.

The electrochemical reaction of FeSb2 with Na is reported for the first time. The first discharge (sodiation) potential profile of FeSb2 is characterized by a gentle slope centered at 0.25 V.

Orthotopic heart transplantation in a child with hereditary spherocytosis.

Hereditary spherocytosis (HS) is a genetic, frequently familial hemolytic blood disease that presents with varying degrees of hemolytic anemia, splenomegaly, and jaundice.The disease arises as a result of defects in any of a number of proteins responsible for maintaining the shape and flexibility of the red blood cell, resulting in an osmotically fragile and characteristically spherical red blood cell. Theoretically, cardiopulmonary bypass can exacerbate hemolysis and subsequent renal dysfunction.

Cardiopulmonary bypass flow rate: a risk factor for hyperlactatemia after surgical repair of secundum atrial septal defect in children.

Objective: Early postoperative hyperlactatemia is seen in some children after surgical repair of secundum atrial septal defect despite apparently normal cardiac output. The objective of the study was to investigate the intraoperative risk factors for hyperlactatemia in patients undergoing atrial septal defect repair.

Methods And Results: A retrospective review of 68 consecutive patients who underwent isolated atrial septal defect repair at Arkansas Children's Hospital between January 2001 and March 2006 was performed.

Anesthetic vaporizer mount malfunction resulting in oxygenation failure after initiating cardiopulmonary bypass: specific recommendations for the pre-bypass checklist.

Modern technologic advances in medicine have allowed commonly used machines to perform safely with very low risk and a high degree of success. To detect or prevent potential malfunctions, professionals routinely perform pre-use checks for equipment such as anesthesia machines and cardiopulmonary bypass (CPB) machines. These machine checklists are not only critical for a safe operation but also have large impacts on outcomes.

Management of a pediatric patient on the Berlin Heart Excor ventricular assist device with argatroban after heparin-induced thrombocytopenia.

We report a 15-year-old male patient who developed type II heparin-induced thrombocytopenia (HIT) after 6 weeks of heparin administration and placement of a Berlin Heart Excor left ventricular assist device (LVAD).

Preliminary single center North American experience with the Berlin Heart pediatric EXCOR device.

For children requiring mechanical circulatory support as a bridge to cardiac transplantation in North America, options previously were limited to extracorporeal membrane oxygenation (ECMO) or centrifugal pump ventricular assist, both of which were suitable for only very short term application and were associated with significant complications and limitations. The Berlin Heart EXCOR ventricular assist device (VAD) was recently introduced into practice in North America to address this deficiency. We report a preliminary single center experience with the EXCOR in 17 children, 13 who received only a left-sided pump and four who required biventricular support.

Superior vena cava perforation in a child from a lawnmower projectile.

Lawnmowers are one of the most frequent causes of mutilating injuries to children. The majority of accidents are caused by negligence of the operator. Most injuries of this type are caused by direct contact with the spinning blade and, less frequently, by projectiles propelled by the blade.

Cardiopulmonary bypass for adults with congenital heart disease: pitfalls for perfusionists.

The fixed incidence of congenital heart defects and improved survival have resulted in increasing numbers of adults with congenital heart disease (CHD) who have undergone complex repairs and/or palliations. Eventually, there will be more adults with CHD than children. They will require cardiac surgical interventions associated with progression of their CHD or for age-related disease, such as coronary revascularization.

The first successful DeBakey VAD child implantation as a bridge to transplant.

A 14-year-old boy with repaired transposition of the great arteries and ventricular septal defect presented with atrial flutter and severe congestive heart failure. Despite successful cardioversion and optimal medical therapy, the patient deteriorated and was supported with extracorporeal membrane oxygenation (ECMO). Two days after initiating ECMO support, we implanted the DeBakey VAD Child ventricular assist device (MicroMed Technology, Inc.

Management of continuous venous gas emboli during extracorporeal life support utilizing the Kolobow gas trap.

Extracorporeal life support (ECLS) with a roller pump system uses a closed cardiopulmonary bypass (CPB) circuit not equipped with a venous reservoir. Hence, gas emboli cannot escape the ECLS circuit, predisposing to clot formation, membrane failure and potential gas embolism. Rarely, some patients may develop a continuous release of gas into the venous circulation from multiple sources.

Successful surgical management of a neonate with a saddle pulmonary embolus.

A female neonate presented with evidence of a massive ventilation-perfusion mismatch. She was subsequently found to have a saddle pulmonary embolus. The infant successfully underwent surgical pulmonary embolectomy.

Expanding the donor pool: use of a donor heart having undergone recent cardiac surgery.

The current shortage of donor organs is a well-recognized global phenomenon. The goal of contemporary transplant practice is to optimize and expand the organ donor pool. Despite biologic and technologic advancements, the single most important limitation remains underutilization and non-recovery of potential organs.

Optimizing cardioplegia strategy for donor hearts.

Variability in organ preservation strategy has thus far prevented meaningful analysis of clinical donor heart cardioplegia strategies. This paper describes our donor heart procurement protocol, techniques, and recovery team responsibilities. We present 21 patients receiving cardiac transplantation at our institution with an adopted cardioplegia protocol.

Determination of the antimony valence state in Eu10Mn6Sb13.

The antimony-121 Mössbauer spectra of Eu10Mn6Sb13 have been measured between 2 and 295 K. Although the Zintl formalism indicates that the nine crystallographically distinct antimony sites in Eu10Mn6Sb13 should have formal valence states of -2, -1, 0, and +1, the Mössbauer spectral isomer shifts reveal that the valence states of the different sites are all quite similar and correspond to an average electronic configuration for antimony of 5s(1.7)5p(4.

Management of potential gas embolus during closure of an atrial septal defect in a three-year-old.

Gas embolism occurring in adult patients supported with cardiopulmonary bypass is usually associated with mechanical complications. Management of gas embolism is less often described for the pediatric or neonatal patient. Measures to counteract gas embolism must be undertaken immediately if a satisfactory outcome is to be achieved.