Transparent, patterned graphene oxide films with tunable electrical conductivity using thermal, chemical, and photoreduction techniques for lab-on-a-chip applications.

This work demonstrates the fabrication of electrically tunable films of graphene oxide (GO). GO thin films were deposited and micropatterned on a cyclic olefin copolymer (COC) substrate using a plasma-enhanced liftoff technique. This article discusses thermal, chemical, and photoreduction methods for controlling the electrical conductivity of the patterned film.

Cases from a Community Hospital…JCHIMP Series #1: 55-Year-Old Male with Acute PE Who Developed Persistent Epistaxis.

This is the first in a new series of case reports that will present real scenarios from our community hospital. The cases are chosen to highlight clinical dilemmas and offer review and perspective on what is currently known about the topic. We present the case of a 55-year-old Caucasian male who presented to the emergency department of our community hospital for worsening dyspnea.

Effect of a Larger Flush Volume on Bioavailability and Efficacy of Umbilical Venous Epinephrine during Neonatal Resuscitation in Ovine Asphyxial Arrest.

The 7th edition of the recommends administration of epinephrine via an umbilical venous catheter (UVC) inserted 2-4 cm below the skin, followed by a 0.5-mL to 1-mL flush for severe bradycardia despite effective ventilation and chest compressions (CC). This volume of flush may not be adequate to push epinephrine to the right atrium in the absence of intrinsic cardiac activity during CC.

Inhaled Nitric Oxide at Birth Reduces Pulmonary Vascular Resistance and Improves Oxygenation in Preterm Lambs.

Resuscitation with 21% O may not achieve target oxygenation in preterm infants and in neonates with persistent pulmonary hypertension of the newborn (PPHN). Inhaled nitric oxide (iNO) at birth can reduce pulmonary vascular resistance (PVR) and improve PaO. We studied the effect of iNO on oxygenation and changes in PVR in preterm lambs with and without PPHN during resuscitation and stabilization at birth.

Randomised trial of epinephrine dose and flush volume in term newborn lambs.

Objectives: Neonatal resuscitation guidelines recommend 0.5-1 mL saline flush following 0.01-0.

Dielectrophoretic Microfluidic Device for Separating Microparticles Based on Size with Sub-Micron Resolution.

This article details the mathematical model of a microfluidic device aimed at separating any binary heterogeneous sample of microparticles into two homogeneous samples based on size with sub-micron resolution. The device consists of two sections, where the upstream section is dedicated to focusing of microparticles, while the downstream section is dedicated to separation of the focused stream of microparticles into two samples based on size. Each section has multiple planar electrodes of finite size protruding into the microchannel from the top and bottom of each sidewall; each top electrode aligns with a bottom electrode and they form a pair leading to multiple pairs of electrodes on each side.

Optimal Oxygen Targets in Term Lambs with Meconium Aspiration Syndrome and Pulmonary Hypertension.

Optimal oxygen saturation as measured by pulse oximetry (Sp) in neonatal lung injury, such as meconium aspiration syndrome (MAS) and persistent pulmonary hypertension of newborn (PPHN), is not known. Our goal was to determine the Sp range in lambs with MAS and PPHN that results in the highest brain oxygen delivery (bDO) and pulmonary blood flow (Qp) and the lowest pulmonary vascular resistance and oxidative stress. Meconium was instilled into endotracheal tubes in 25 near-term gestation lambs, and the umbilical cord was occluded to induce asphyxia and gasping, causing MAS and PPHN.

Simulation of a microfluidic device employing dielectrophoresis for liquid biopsy.

This article details simulation based study of cell separation in a dielectrophoretic microfluidic device. The device consists of a narrow microchannel connected to a wide microchannel with several finite sized planar interdigitated transducer electrodes protruding into the narrow microchannel from one of its sidewalls. In the narrow microchannel, the circulating tumor cells are subjected to positive dielectrophoresis while the regular cells are subjected to negative dielectrophoresis to achieve separation and as all cells move in to the wide microchannel, the physical distance between the two types of cells increases thereby making their collection from the device easier.

Modeling a Dielectrophoretic Microfluidic Device with Vertical Interdigitated Transducer Electrodes for Separation of Microparticles Based on Size.

This article conceptualizes and mathematically models a dielectrophoretic microfluidic device with two sets of interdigitated transducer vertical electrodes for separation of a binary heterogeneous mixture of particles based on size; each set of electrodes is located on the sidewalls and independently controllable. To achieve separation in the proposed microfluidic device, the small microparticles are subjected to positive dielectrophoresis and the big microparticles do not experience dielectrophoresis. The mathematical model consists of equations describing the motion of each microparticle, fluid flow profile, and electric voltage and field profiles, and they are solved numerically.

Glucose Levels during the First 24 Hours following Perinatal Hypoxia.

Objective: Hypoglycemia is a significant risk factor for perinatal brain injury and adverse outcomes, particularly in infants requiring resuscitation following hypoxic ischemic (HI) insult. We aimed to study blood glucose (BG) levels in physiologically stressed infants in the presence or absence of epinephrine (Epi) administration at resuscitation in the first 24 hours after birth.

Study Design: A retrospective chart review of all infants with heart rate (HR) < 100/min at 1 minute requiring positive pressure ventilation (PPV) at birth was performed.

Nozzle-Shaped Electrode Configuration for Dielectrophoretic 3D-Focusing of Microparticles.

An experimentally validated mathematical model of a microfluidic device with nozzle-shaped electrode configuration for realizing dielectrophoresis based 3D-focusing is presented in the article. Two right-triangle shaped electrodes on the top and bottom surfaces make up the nozzle-shaped electrode configuration. The mathematical model consists of equations describing the motion of microparticles as well as profiles of electric potential, electric field, and fluid flow inside the microchannel.

Dielectrophoresis Multipath Focusing of Microparticles through Perforated Electrodes in Microfluidic Channels.

This paper presents focusing of microparticles in multiple paths within the direction of the flow using dielectrophoresis. The focusing of microparticles is realized through partially perforated electrodes within the microchannel. A continuous electrode on the top surface of the microchannel is considered, while the bottom side is made of a circular meshed perforated electrode.

Continued Enteral Feeding Is Beneficial in Hypoglycemic Infants Admitted to Intensive Care for Parenteral Dextrose Therapy.

There is variability in practice among care providers on feeding infants admitted with neonatal hypoglycemia (NH) for parenteral dextrose. We compared clinical outcomes in infants who were fed (NH-Fed) and hypoglycemic infants who were kept nothing per os (NPO) (NH-NPO) at the time of initiation of intravenous (IV) dextrose. We performed a retrospective review of all newborn infants admitted to the neonatal intensive care unit with NH for IV dextrose.

Oxygenation and Hemodynamics during Chest Compressions in a Lamb Model of Perinatal Asphyxia Induced Cardiac Arrest.

The current guidelines recommend the use of 100% O₂ during resuscitation of a neonate requiring chest compressions (CC). Studies comparing 21% and 100% O₂ during CC were conducted in postnatal models and have not shown a difference in incidence or timing of return of spontaneous circulation (ROSC). The objective of this study is to evaluate systemic oxygenation and oxygen delivery to the brain during CC in an ovine model of perinatal asphyxial arrest induced by umbilical cord occlusion.

Bioavailability of endotracheal epinephrine in an ovine model of neonatal resuscitation.

Background: Distressed infants in the delivery room and those that have completed postnatal transition are both resuscitated according to established neonatal resuscitation guidelines, often with endotracheal (ET) epinephrine at the same dose. We hypothesized that ET epinephrine would have higher bioavailability in a post-transitional compared to transitioning newborn model due to absence of fetal lung liquid and intra-cardiac shunts.

Methods: 15 term fetal (transitioning newborn) and 6 postnatal lambs were asphyxiated by umbilical cord and ET tube occlusion respectively.

Physical examination score predicts need for surgery in neonates with necrotizing enterocolitis.

Objective: To evaluate the utility of a standardized physical exam score (PE-NEC) in predicting need for surgery or death in neonates with necrotizing enterocolitis (NEC).

Methods: This prospective, multicenter, observational study was conducted from 3/1/14 to 2/29/16 with three regional perinatal centers in upstate New York. Infants with NEC Bell's Stage ≥ 2 had physical exams and laboratory data recorded at 12-24 h intervals for 48 h following diagnosis.

Dielectrophoresis-based 3D-focusing of microscale entities in microfluidic devices.

This article presents a validated mathematical model of a dielectrophoresis (DEP)-based microfluidic device capable of 3D-focusing microscale entities at any lateral location inside the microchannel. The microfluidic device employs planar, independently controllable, interdigitated transducer (IDT) electrodes on either side of the microchannel. The developed model is used for understanding the influence of different geometric and operating parameters on 3D focusing, and it comprises of motion equation, Navier-Stokes equation, continuity equation, and electric potential equation (Laplace equation).

Microfluidics Based Magnetophoresis: A Review.

Magnetophoresis, the manipulation of trajectory of micro-scale entities using magnetic forces, as employed in microfluidic devices is reviewed at length in this article. Magnetophoresis has recently garnered significant interest due to its simplicity, in terms of implementation, as well as cost-effectiveness while being efficient and biocompatible. Theory associated with magnetophoresis is illustrated in this review along with different sources for creating magnetic field gradient commonly employed in microfluidic devices.

Lateral fluid flow fractionation using dielectrophoresis (LFFF-DEP) for size-independent, label-free isolation of circulating tumor cells.

This short communication introduces a continuous-flow, dielectrophoresis-based lateral fluid flow fractionation microdevice for detection/isolation of circulating tumor cells in the presence of other haematological cells. The device utilizes two sets of planar interdigitated transducer electrodes micropatterned on top of a glass wafer using standard microfabrication techniques. A microchannel with a single inlet and two outlets, realized in polydimethylsiloxane, is bonded on the glass substrate.

Analysis of dielectrophoresis based 3D-focusing in microfluidic devices with planar electrodes.

This article models a dielectrophoresis based approach for achieving 3D focusing, of micro-scale objects, in microfluidic devices. The microfluidic device employs four planar electrodes; two electrodes each on the top and bottom surface of the microchannel and each slightly protrude into the microchannel. Each electrode establishes electric field with the neighboring electrode on the same and opposite surfaces.

Persistent Pulmonary Hypertension in the Newborn.

Persistent pulmonary hypertension of the newborn (PPHN) is a syndrome of failed circulatory adaptation at birth due to delay or impairment in the normal fall in pulmonary vascular resistance (PVR) that occurs following birth. The fetus is in a state of physiological pulmonary hypertension. In utero, the fetus receives oxygenated blood from the placenta through the umbilical vein.

Continuous Chest Compressions During Sustained Inflations in a Perinatal Asphyxial Cardiac Arrest Lamb Model.

Objective: Continuous chest compressions are more effective during resuscitation in adults. Sustained inflation rapidly establishes functional residual capacity in fluid-filled lungs at birth. We sought to compare the hemodynamics and success in achieving return of spontaneous circulation in an asphyxial cardiac arrest lamb model with transitioning fetal circulation and fluid-filled lungs between subjects receiving continuous chest compressions during sustained inflation and those receiving conventional 3:1 compression-to-ventilation resuscitation.

Hemodynamics and gas exchange during chest compressions in neonatal resuscitation.

Purpose: Current knowledge about pulmonary/systemic hemodynamics and gas exchange during neonatal resuscitation in a model of transitioning fetal circulation with fetal shunts and fluid-filled alveoli is limited. Using a fetal lamb asphyxia model, we sought to determine whether hemodynamic or gas-exchange parameters predicted successful return of spontaneous circulation (ROSC).

Methods: The umbilical cord was occluded in 22 lambs to induce asphyxial cardiac arrest.