CFD-based bioreactor model with proportional-integral-derivative controller functionality for dissolved oxygen and pH.

A physics-based model for predicting cell culture fluid properties inside a stirred tank bioreactor with embedded PID controller logic is presented. The model evokes a time-accurate solution to the fluid velocity field and overall volumetric mass transfer coefficient, as well as the ongoing effects of interfacial mass transfer, species mixing, and aqueous chemical reactions. The modeled system also includes a direct coupling between process variables and system control variables via embedded controller logic.

Experimental and computational characterization of mass transfer in high turndown bioreactors.

Single-use bioreactors (SUBs, or disposable bioreactors) are extensively used for the clinical and commercial production of biologics. Despite widespread application, minimal results have been reported utilizing the turndown ratio; an operation mode where the working range of the bioreactor can be expanded to include low fluid volumes. In this work, a systematic investigation into free surface mass transfer and cell growth in high turndown single-use bioreactors is presented.

Modeling multiphase fluid flow, mass transfer, and chemical reactions in bioreactors using large-eddy simulation.

We present a transient large eddy simulation (LES) modeling approach for simulating the interlinked physics describing free surface hydrodynamics, multiphase mixing, reaction kinetics, and mass transport in bioreactor systems. Presented case-studies include non-reacting and reacting bioreactor systems, modeled through the inclusion of uniform reaction rates and more complex biochemical reactions described using Contois type kinetics. It is shown that the presence of reactions can result in a non-uniform spatially varying species concentration field, the magnitude and extent of which is directly related to the reaction rates and the underlying variations in the local volumetric mass transfer coefficient.

Acute Effects of Various Movement Noise in Differential Learning of Rope Skipping on Brain and Heart Recovery Analyzed by Means of Multiscale Fuzzy Measure Entropy.

In search of more detailed explanations for body-mind interactions in physical activity, neural and physiological effects, especially regarding more strenuous sports activities, increasingly attract interest. Little is known about the underlying manifold (neuro-)physiological impacts induced by different motor learning approaches. The various influences on brain or cardiac function are usually studied separately and modeled linearly.

Mapping the protein profile involved in the biotransformation of organoarsenicals using an arsenic metabolizing bacterium.

Alkaliphilus oremlandii strain OhILAs, a gram-positive bacterium, has been shown to ferment lactate as well as use arsenate and roxarsone as a terminal electron acceptor. This study examines the proteome expressed under four growth conditions to further elucidate the bacterial metabolism of inorganic and organic arsenic. The four growth conditions include, sodium lactate (as fermentative control), sodium lactate with 3-nitro-4-hydroxybenzenearsonic acid (roxarsone), sodium lactate with 3-amino-4-hydroxybenzenearsonic acid (3A4HBAA), and sodium lactate with sodium arsenate.

A randomized controlled comparison between combined spinal-epidural and single-shot spinal techniques in morbidly obese parturients undergoing cesarean delivery: time for initiation of anesthesia.

Background: There is no current consensus on the optimal technique for subarachnoid anesthesia in morbidly obese parturients even though some providers prefer the combined spinal-epidural (CSE) over single-shot spinal (SSS) technique. In this randomized controlled study, we compared the time required for initiation of subarachnoid anesthesia between SSS and CSE techniques in morbidly obese parturients undergoing elective cesarean delivery.

Methods: Morbidly obese parturients presenting for elective cesarean delivery were randomized to receive subarachnoid anesthesia performed either with a SSS or a CSE technique.

Personal care products and endocrine disruption: A critical review of the literature.

This article reviews laboratory and epidemiological research into the endocrine disruptive effects of components of personal care products, namely, phthalate esters, parabens, ultraviolet (UV) filters, polycyclic musks, and antimicrobials. High doses of phthalates in utero can produce “phthalate syndrome,” demasculinizing effects in male rat offspring due to impaired testosterone production by fetal testes. However, evidence linking phthalate exposure to similar effects in humans appears inconclusive.

An injectable thiol-acrylate poly(ethylene glycol) hydrogel for sustained release of methylprednisolone sodium succinate.

Clinically available injectable hydrogels face technical challenges associated with swelling after injection and toxicity from unreacted constituents that impede their performance as surgical biomaterials. To overcome these challenges, we developed a system where chemical gelation was controlled by a conjugate Michael addition between thiol and acrylate in aqueous media, with 97% monomer conversion and 6 wt.% sol fraction.

Water flow in carbon nanotubes: transition to subcontinuum transport.

The structure and flow of water inside 75 and 150 nm-long carbon nanotubes with diameters ranging from 0.83 to 1.66 nm are examined using molecular dynamics simulation.

Reassessing fast water transport through carbon nanotubes.

Pressure-driven water flow through carbon nanotubes (CNTs) with diameters ranging from 1.66 to 4.99 nm is examined using molecular dynamics simulation.

Dural puncture with a 27-gauge Whitacre needle as part of a combined spinal-epidural technique does not improve labor epidural catheter function.

Background: This prospective, double-blind, randomized study was designed to examine whether the combined spinal-epidural technique without subarachnoid drug administration improved epidural catheter function when compared with the traditional epidural technique.

Methods: After institutional review board approval and informed consent, 251 healthy laboring parturients were randomly assigned to either group DP (combined spinal-epidural technique with 27-gauge Whitacre needle dural puncture but without subarachnoid drug administration) or group NoDP (traditional epidural technique). Patient-controlled epidural analgesia was initiated with 0.

Relation of residency selection factors to subsequent orthopaedic in-training examination performance.

Objectives: Orthopaedic surgery remains one of the most competitive specialties, with more than a 99% match fill rate in the past several years. An oversupply of qualified applicants leads to intense competition for these residency spots, allowing program directors to be more selective in choosing their future residents. Although many previous studies have documented factors important to program directors in the admission process, less is known about how preselection factors correlate with subsequent performance in a residency program.

Sudden cardiac death in children and adolescents: introduction and overview.

Sudden unexpected cardiac death (SCD) in a child or adolescent is a devastating event with serious impact on the family, the school, and the community. This article reviews the epidemiology of SCD in children and adolescents and includes a discussion of its incidence and etiologies. It also discusses strategies for prevention.

Impact of implant design on femoral head hemiresurfacing arthroplasty.

Two consecutive series of cemented femoral hemiresurfacing arthroplasty for patients with Ficat Stage III and early Stage IV osteonecrosis of the femoral head were studied to identify the impact of design on the clinical and radiographic results. Group I (30 patients, 33 hips) components had a cobalt chrome shell with a tapered inner dimension, no stem, and sizes in 2-mm increments. Group II (37 patients, 51 hips) components differed by adding a proportional stem, increased spherical coverage, and sizes in 1-mm increments.

Influence of volunteer wheat plant condition on movement of the wheat curl mite, Aceria tosichella, in winter wheat.

The wheat curl mite (WCM), Aceria tosichella Keifer, is the vector of wheat streak mosaic virus and high plains virus which cause significant crop loss in winter wheat throughout the western Great Plains. Volunteer wheat emerging before harvest, as a result of severe hail, is the primary source of mites and virus that infect fall-planted winter wheat. Wind-borne movement of the WCM is of key importance in the spread and infection of the virus complex.

Cystatin C in cerebrospinal fluid is not a diagnostic test for pain in humans.

A recent subtractive cDNA cloning study in rats demonstrated an unexpected increase in expression of the proteinase inhibitor, cystatin C in the spinal cord during acute peripheral inflammation, suggesting this protein may be involved in the pathogenesis of persistent pain. A subsequent study of 10 women suggested that prolonged labor pain resulted in increased cystatin C concentrations in cerebrospinal fluid, and that this could be used as a biomarker for pain. To confirm and extend these observations, we measured cystatin C concentrations in cerebrospinal fluid in 131 subjects: 30 normal volunteers without pain, 25 women at elective cesarean section without pain, 60 women in labor with severe pain, and 16 patients with chronic neuropathic pain and tactile allodynia.

Safety of foods derived from genetically modified plants.

Biopharmaceuticals have been available for clinical use for nearly three decades, but foods derived from agribiotechnology have been available for just under a decade. Controversy surrounding foods from genetically modified (GM) plants has focused primarily upon their allergenicity, with lesser concerns about antibiotic resistance genes. Concerns are related to possible environmental impacts on non-human species, including effects on non-target species (e.

Aspartame: review of safety.

Over 20 years have elapsed since aspartame was approved by regulatory agencies as a sweetener and flavor enhancer. The safety of aspartame and its metabolic constituents was established through extensive toxicology studies in laboratory animals, using much greater doses than people could possibly consume. Its safety was further confirmed through studies in several human subpopulations, including healthy infants, children, adolescents, and adults; obese individuals; diabetics; lactating women; and individuals heterozygous (PKUH) for the genetic disease phenylketonuria (PKU) who have a decreased ability to metabolize the essential amino acid, phenylalanine.

Pharmacological aspects of erectile dysfunction.

Erectile dysfunction (ED) is a common problem with a prevalence of approximately 50% in men aged 40 to 70. There are several etiologies for ED including vasculogenic, neurogenic, hormonal and/or psychogenic factors; one-fourth of ED cases can be drug-related. Penile erection involves a complex interaction between the CNS and local factors.

Inhibition of the mitochondrial permeability transition by aldehydes.

Fructose has been shown to protect hepatocyte viability during hypoxia or exposure to mitochondrial electron transport inhibitors. We report here that the fructose metabolite D-glyceraldehyde (D-GA) is a good inhibitor of the mitochondrial permeability transition pore (PTP) in isolated rat liver mitochondria. We propose that a substantial portion of the protective effect of fructose on hepatocytes is due to D-GA inhibition of the permeability transition.

Ropivacaine 0.075% and bupivacaine 0.075% with fentanyl 2 microg/mL are equivalent for labor epidural analgesia.

Unlabelled: Fifty percent effective dose estimates for ropivacaine and bupivacaine suggest that ropivacaine is 40% less potent than bupivacaine to initiate labor analgesia. At clinically used concentrations, however, the drugs seem indistinguishable for initiating and maintaining labor analgesia. We designed this study to evaluate a concentration near the reported 50% effective dose values for ropivacaine and bupivacaine in an attempt to detect differences between the drugs during routine clinical use.