Thin Barium Research Articles

The Effect of Oral Diet Training in Indwelling Nasogastric Tube Patients with Prolonged Dysphagia.

Background: Patients with severe dysphagia are usually fed using a nasogastric tube (NGT). Many patients who receive long-term NGT feeding are unable to obtain sufficient nutrients orally immediately after NGT removal. Thus, a transitional period involving oral diet training is required to transition from NGT feeding to exclusive oral feeding. We aimed to investigate the therapeutic effect of oral diet training in indwelling NGT patients with prolonged dysphagia. Methods: A total of 175 patients who were fed using an NGT for more than 4 weeks were enrolled. Their swallowing function was evaluated by a videofluoroscopic swallowing study (VFSS). During the VFSS, patients received thick and thin barium while the NGT was inserted. Then, the patients underwent a VFSS without an NGT thirty minutes after NGT removal. If a patient had no aspiration with NGT inserted during the VFSS, oral diet training combined with NGT feeding was recommended. Results: Of the 49 indwelling NGT patients who were recommended to receive oral diet training, 39 (79.6%) transitioned to exclusive oral feeding. A transition period of 2-8 weeks was required for them to achieve full oral feeding. Patients who were eligible for oral feeding trials showed no significant aspiration during the VFSS with an NGT inserted and had sufficient cough function. Patients who required prolonged NGT feeding and who could not complete oral trials showed significant aspiration during the VFSS when an NGT was inserted. Conclusions: This study demonstrated that oral diet training combined with NGT feeding is safe in patients with prolonged dysphagia who have sufficient cough function and no aspiration during VFSS. We suggest that if the patient is a proper candidate for NGT removal, direct oral feeding training with an NGT inserted could be a useful therapeutic strategy during the transitional period from long-term NGT feeding to successful oral feeding.

Phase Transformations and Properties of Thin Barium Neodymium Ferroniobate Films in the Temperature Range from –190 to 200°C

Phase Transformations and Properties of Thin Barium Neodymium Ferroniobate Films in the Temperature Range from –190 to 200°C

Visualization of implanted mesh in the pelvic reconstructive surgery using an X-ray-detectable thread

Visualization of the implanted mesh after a pelvic floor repair surgery is important for evaluating mesh-related complications. We made an X-ray-detectable mesh and studied the histocompatibility and toxicity of it. A thin barium sulfate thread was weaved on a traditional polypropylene mesh to make it X-ray detectable. The cytotoxicity of the mesh was tested by the MTT assay on L929 cell line. The histocompatibility and toxicity of mesh were evaluated in rabbits. Meshes were first implanted intraperitoneally. On postoperative day 7, bloods were tested to estimate the acute toxicity of meshes. After 6months, rabbits were sacrificed and local inflammatory reaction and tissue regeneration at implantation sites were estimated by the HE stain and Masson stain. In addition, CT scans were performed after surgeries to display the location and shape of implanted meshes. Compared to the polypropylene mesh group, no significant difference was observed in the X-ray-detectable mesh group on both in vitro cytotoxicity and in vivo acute and chronic toxicity. The amounts of extra cellular matrix between two groups did not differ. Through CT scan and 3D remodeling, the barium sulfate thread clearly revealed the position and shape of the X-ray-detectable mesh, whereas the traditional mesh was invisible under CT scan. Adding a thin barium sulfate thread on the polypropylene mesh does not change its histocompatibility or toxicity in rabbit model. The barium sulfate thread can effectively show the location and shape of implanted mesh under CT scan.

Boundary influence on the fields and arrangement of the needle domains in barium titanate single crystals

The superposition theory is adopted to study the boundary value problem of needle domains in barium titanate single crystals, which decomposes into an infinite-medium solution and a complementary solution. The model of an equivalent edge dislocation and line charge is adopted to calculate the fields due to the discrete needle domains in an infinite medium. The complementary solutions are obtained from a linear elastic boundary value problem using the finite element method. The influence of boundaries on the fields and arrangement of the needles in thin barium titanate single crystals is analysed, by considering traction-free boundaries and using the plane stress approximation. According to the principle of minimum potential energy, it is found that pairs of parallel needle domains can be stabilized if the effective charge associated with the needle tips is reduced to 48% of the material’s full polarization charge. The evolution of comb-like arrays of needle domains under compressive mechanical load is simulated, and the results are found to be qualitatively similar to experimental observations which have not previously been explained theoretically.

Variations in Hyoid Kinematics Across Liquid Consistencies in Healthy Swallowing.

PurposeJudgments regarding hyoid movement are frequently included in evaluations of swallowing. However, the literature lacks reference values for measures of hyoid kinematics in healthy swallowing. This study explores hyoid movement across the continuum from thin to extremely thick liquids.MethodParticipants were 39 healthy adults under the age of 60 years (19 men) who underwent videofluoroscopy involving three sips each of 20% w/v thin barium and six sips each of slightly, mildly, moderately, and extremely thick barium. Half of the thickened stimuli were prepared using xanthan gum; and half, with a starch-based thickener. Sip volume was derived from pre- and post-sip cup weights. Hyoid position was tracked frame-by-frame relative to the anterior–inferior corner of C4. Measures of peak hyoid position (along the XY axis) were normalized to a C2–C4 scalar, and measures of time-to-peak position, speed, and time-to-peak speed were derived. As a first step, Spearman's correlations confirmed the influence of sip volume on these hyoid measures. Linear mixed-effects models then explored the effects of stimulus, sip volume, and task repetition on the dependent variables.ResultsThe data set comprised 975 swallows with available hyoid tracking data. Sip volume was correlated with peak hyoid XY position (rs = .15, p < .01), time-to-peak position (rs = −.15, p < .05), and speed (rs = .13, p < .01). No significant differences in hyoid kinematics were found across stimuli.ConclusionMeasures of hyoid movement in healthy swallowing remain stable across the range from thin to extremely thick liquids with no systematic alterations in hyoid position or kinematics.

Quantitative Videofluoroscopic Analysis of Swallowing Physiology and Function in Individuals With Chronic Obstructive Pulmonary Disease.

PurposeDysphagia is a serious extra pulmonary manifestation of chronic obstructive pulmonary disease (COPD). However, the nature of abnormalities in swallowing physiology in COPD has yet to be clearly established. We explored the frequency of swallowing measures outside the healthy reference range in adults with COPD.MethodParticipants were 28 adults aged 41–79 years (18 men, 20 women) with stable COPD. Disease severity was classified as GOLD (Global Initiative For Chronic Obstructive Lung Disease) Stages 1 (4%), 2 (25%), 3 (53%), and 4 (18%). Participants underwent a videofluoroscopy and swallowed 20% w/v thin barium in, followed by 20% w/v mildly, moderately, and extremely thick barium prepared with a xanthan gum thickener. Blinded duplicate ratings of swallowing safety, efficiency, kinematics, and timing were performed according to the ASPEKT method (Analysis of Swallowing Physiology: Events, Kinematics and Timing). Comparison data for healthy adults aged < 60 years were extracted from an existing data set. Chi-square and Fisher's exact tests compared the frequencies of measures falling < 1 SD/ > 1 SD from mean reference values (or < the first or > the third quartile for skewed parameters).ResultsParticipants with COPD did not display greater frequencies of penetration–aspiration, but they were significantly more likely (p < .05) to display incomplete laryngeal vestibule closure (LVC), longer time-to-LVC, and shorter LVC duration. They also displayed significantly higher frequencies of short upper esophageal sphincter opening, reduced pharyngeal constriction, and pharyngeal residue.ConclusionThis analysis reveals differences in swallowing physiology in patients with stable COPD characterized by impaired safety related to the mechanism, timing, and duration of LVC and by impaired swallowing efficiency with increased pharyngeal residue related to poor pharyngeal constriction.

S2004 A Hard Pill to Swallow: Oropharyngeal Dysphagia Secondary to Antipsychotics

INTRODUCTION: Dysphagia can be anatomically categorized as either oropharyngeal or esophageal based on where and when the patient endorses difficulty swallowing and oropharyngeal dysphagia secondary to antipsychotic medications is often overlooked. Antipsychotics, especially the first generation, have been classically associated with extrapyramidal symptoms such as dystonia, akathisia, tremors and tardive dyskinesia. Dysphagia is an uncommon side effect of antipsychotics which can lead to choking, asphyxiation, or even aspiration pneumonia. Antipsychotic medications block the D2 receptors in the nigrostriatal pathway which are also hypothesized to regulate motor neurons responsible for complex muscle movements such as swallowing. Here, we present a case of severe dysphagia leading to failure to thrive in an adult after initiation of a first-generation antipsychotic. CASE DESCRIPTION/METHODS: A 69-year-old male with a history of schizoaffective disorder who presented with a one-month history of difficulty swallowing. Three days before this symptom, he was started on Haloperidol for his schizoaffective disorder. He complained of difficulty in initiating a swallow, pointing towards his neck region, which was soon followed by coughing and choking with both solid and liquid food. He stopped eating and drinking due to the overwhelming fear of choking leading to significant weight loss and cachexia. His physical examination was significant for temporal wasting, bradykinesia, cogwheel rigidity and diffuse hyperreflexia. Labs were unremarkable. A barium swallow revealed a difficulty in initiation of swallow, aspiration of thin barium with no spontaneous cough and poor pharyngeal constriction. CT soft tissue/neck revealed no evidence of extrinsic compression and MRI brain was done to rule out a stroke. An upper endoscopy was not performed as the barium swallow provided sufficient information to clinch the diagnosis. The patient’s antipsychotics were discontinued, and his nutritional status had to be optimized with NG tube feedings. After two weeks, the patient was transitioned to a liquid diet and discharged from the hospital. DISCUSSION: Antipsychotic-related oropharyngeal dysphagia is an uncommon side effect; however, it has been reported in case reports. It is important to identify this side effect, especially in elderly patients or patients with pre-existing anatomical or functional changes as it can lead to complications such as asphyxiation and aspiration pneumonia contributing to mortality.Figure 1.: Barium swallow study showing heavy pooling of barium in vallecula and pyriform sinuses.Figure 2.: Barium swallow revealing poor pharyngeal constriction leading to aspiration of thin barium without coughing.

Structure, optical properties and resistance to laser radiation of thin barium disilicide films grown on silicon

Polycrystalline and oriented films of barium disilicide (BaSi2) with a thickness of up to 100 nm were formed on silicon (111) substrates by high-temperature (800 ° C) solid-phase (single-stage and two-stage) annealing. The single phase of barium disilicide films and their semiconductor nature have been proven to be below 1.25 eV according to X-ray and optical spectroscopic methods. Two preferential orientations of the BaSi2 crystallites were detected and their orientation was determined in the films formed by two-stage annealing. According to the calculations of the parameters of the crystal structure of BaSi2 films, a compression of the unit cell volume from 2.7% to 5.13% was found, depending on the cooling time to room temperature. The stability of the films to laser radiation was studied by registering the Raman spectra with a variable power of laser radiation. The maximum power density of the laser beam (3⋅109 W/m2), which does not lead to the beginning of the destruction of these films, wasdetermined.

ILEO-COLIC INTUSSUSCEPTION;

Objective: To evaluate the success rate of hydrostatic reduction of intussusceptionand incidence of complications in late presenting cases. Study Design: prospective study.Place and duration of study: Study was carried out in Armed Forces Institute of Radiologyand Imaging Rawalpindi and different Combine Military Hospitals during last 5 years. Materialsand Methods: All the children up to 2 years age with diagnosis of ileo-colic intussusceptionand 3 days or less history of onset of symptoms were included in the study. Patients with signsof perforation, suspicion of lead point or long intussusceptum protruding through rectum wereexcluded. After plain film evaluation, thin barium was instilled through Foleys catheter underfluoroscopic guidance. Rule of 3 was followed and reduction was considered successful whencontrast refluxed into terminal ileal segment. Follow up plain x-ray and ultrasound was doneafter 48 hours to rule out recurrence. Results: Hydrostatic reduction was successful in 18 outof 21 patients collected during last five years. Reduction was incomplete in one case whileperforation was observed in 2 cases. These complications were observed in the largest group(52%) of patients reporting on 3rd day of onset of symptoms. A significant number (38%) ofpatients reached the hospital within 48 hours. Only 2 (10%) patients presented in first 24 hrsbut uneventful reduction was possible in later two groups. Conclusions: Careful hydrostaticreduction in cases of ileo-colic intussusception reporting within 72 hrs will reduce hospital stayand patient morbidity in most of the cases.

Electric-field-dependent mechanical and electrical properties of barium strontium titanate films for tunable device applications

Developing the novel electric field tunable, reconfigurable, adaptive and frequency-agile microwave devices with specific properties involves technological and scientific activities in the studying of material properties. Measurements of its properties could be a difficult and expensive issue, especially when it concerns thin-film ferroelectrics. Their electromechanical properties change significantly under applied DC bias field. The material coefficients of barium strontium titanate thin films are still unknown; therefore, it is expedient to carry out their calculations. In the present paper, the linear equations of piezoelectric effect have been written for thin barium strontium titanate films under DC bias electric field in paraelectric phase (induced piezoelectric effect) based on the grand potential of Landau theory of phase transitions. The dependence of material constants for thin films of Ba0.65Sr0.35TiO3 (BST65) on the applied planar field at different lattice misfit strains has been studied for this phase. All induced piezoelectric moduli show extreme behavior during field alteration. Elastic moduli show similar abnormal behavior. The alterations increase as misfit strain is approaching the critical value.

The Interaction Between Accretion from the Interstellar Medium and Accretion from the Evolved Binary Component in Barium Stars

The reanalysis of the previously published abundance pattern of mild barium star HD202109 (ζ Cyg) and the chemicalcompositions of 129 thin disk barium stars facilitated the search for possible correlations of different stellar parameters withsecond ionization potentials of chemical elements. Results show that three valuable correlations exist in the atmospheres ofbarium stars. The first is the relationship between relative abundances and second ionization potentials. The second is theage dependence of mean correlation coefficients of relative abundances vs. second ionization potentials, and the third one isthe changes in correlation coefficients of relative abundances vs. second ionization potentials as a function of stellar spatialvelocities and overabundances of s-process elements. These findings demonstrate the possibility of hydrogen and heliumaccretion from the interstellar medium on the atmospheres of barium stars.

Back-contacted BaSi2 solar cells: an optical study.

We present the optical investigation of a novel back-contacted architecture for solar cells based on a thin barium (di)silicide (BaSi2) absorber. First, through the analysis of absorption limits of different semiconducting materials, we show the potential of BaSi2 for photovoltaic applications. Then, the proposed back contacted BaSi2 solar cell design is investigated and optimized. An implied photocurrent density of 40.3 mA/cm2 in a 1-μm thick absorber was achieved, paving the way for novel BaSi2-based thin-film solar cells.

Dysphagia in infants with single ventricle anatomy following stage 1 palliation: Physiologic correlates and response to treatment.

Deficits in swallowing physiology are a leading morbidity for infants with functional single ventricles and systemic outflow tract obstruction following stage 1 palliation. Despite the high prevalence of this condition, the underlying deficits that cause this post-operative impairment remain poorly understood. Identify the physiologic correlates of dysphagia in infants with functional single ventricles and systemic outflow tract obstruction following stage 1 palliative surgery. Postoperative fiberoptic laryngoscopies and videofluoroscopic swallow studies (VFSS) were conducted sequentially on infants with functional single ventricles following stage 1 palliative surgery. Infants were dichotomized as having normal or impaired laryngeal function based on laryngoscopy findings. VFSS were evaluated frame-by-frame using a scale that quantifies performance within 11 components of swallowing physiology. Physiologic attributes within each component were categorized as high functioning or low functioning based on their ability to support milk ingestion without bolus airway entry. Thirty-six infants (25 male) were included in the investigation. Twenty-four underwent the Norwood procedure and twelve underwent the Hybrid procedure. Low function physiologic patterns were observed within multiple swallowing components during the ingestion of thin barium as characterized by ≥4 sucks per swallow (36%), initiation of pharyngeal swallow below the level of the valleculae (83%), and incomplete late laryngeal vestibular closure (56%) at the height of the swallow. Swallowing deficits contributed to aspiration in 50% of infants. Although nectar thick liquids reduced the rate of aspiration (P = .006), aspiration rates remained high (27%). No differences in rates of penetration or aspiration were observed between infants with normal and impaired laryngeal function. Deficits in swallowing physiology contribute to penetration and aspiration following stage 1 palliation among infants with normal and impaired laryngeal function. Although thickened liquids may improve airway protection for select infants, they may inhibit their ability to extract the bolus and meet nutritional needs.

Molecular statics simulations of ferroelectric nanofilms

AbstractSmart materials are of great interest not only for scientific, but also for technological reasons due to ongoing miniaturization and rapid developments in manufacturing technologies of nanocomponents [1]. Therefore, simulations on the nanometer length scale are becoming more important in order to fundamentally understand and predict the complex material behavior of ferroelectric nanocomponents, such as ferroelectric nanofilms or nanowires. We apply a previously developed extended molecular statics algorithm [2] to simulate ferroelectric barium titanate nanofilms. The algorithm is able to also consider mechanical stress explicitly whereas most molecular simulations of ferroelectrics are restricted to NVT‐ensembles. We simulate a stress relaxed ultra thin barium titanate film and apply compressive strain in order to investigate size effects of ferroelectric nanofilms. (© 2016 Wiley‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)

Suitable Food Textures for Videofluoroscopic Studies of Swallowing in Esophageal Cancer Cases to Prevent Aspiration Pneumonia.

To determine suitable food textures for videofluoroscopic study of swallowing (VFSS), in order to predict and prevent subsequent aspiration pneumonia in esophageal cancer patients with dysphagia after surgery. We evaluated 45 hospitalized esophageal cancer patients who underwent surgery between January 2012 and December 2013. The control group consisted of 43 patients treatmed from January 2010 until December 2011 and were not examined by VFSS. Test foods, which were presented in order of increasing thickness, included thin barium sulfate (Ba) liquid (3 or 10 ml), slightly thickened Ba liquid (3 or 10 ml), a spoonful of Ba jelly, and a spoonful of Ba puree. Patients could most safely swallow puree, followed by jelly. The 3mL samples of both the thin and thick liquids put patients at risk for aspiration pneumonia, with incidence rates of 13% and 11%, respectively. While 64.4% of patients could swallow all test foods and liquids safely, 35.6% were at risk for aspiration pneumonia when swallowing liquids. Even though >30% of patients were at risk, only 1 (2.2%) in the VFSS group developed aspiration pneumonia, which occurred at the time of admission. Following VFSS, no incidence of aspiration pneumonia was observed. However, aspiration pneumonia occurred in 4 (9.3%) control patients during hospitalization. Postoperative esophageal cancer patients were more likely to aspirate any kind of liquid than solid foods, such as jellies. VFSS is very useful in determining suitable food textures for postoperative esophageal cancer patients.

The structure and dielectric properties of thin barium zirconate titanate films obtained by RF magnetron sputtering

Submicron thin layers of BaZrxTi1–xO3 are grown in-situ by RF magnetron sputtering of a ceramic target (x = 0.50) on a substrate of Pt/r-cut leucosapphire Al2O3. It is shown that the composition of the ferroelectric layer is not identical to the composition of the sputtered target and is shifted toward barium zirconate. The reasons for such behavior are discussed. The obtained samples are characterized by high breakdown voltages (1 MV/cm and higher). The structural and high-frequency dielectric properties are studied, and high tunability of the capacitance of thin layers is revealed.

Increased Bolus Volume Effect on Delayed Pharyngeal Swallowing Response in Post-stroke Oropharyngeal Dysphagia: A Pilot Study.

ObjectiveTo confirm a relationship between the pharyngeal response and bolus volume, and examine whether increasing the fluid bolus volume can improve penetration and aspiration for stroke dysphagic patients.MethodsTen stroke patients with a delayed pharyngeal response problem confirmed by a videofluoroscopic swallowing study (VFSS) were enrolled. Each subject completed two swallows each of 2 mL, 5 mL, and 10 mL of barium liquid thinned with water. The pharyngeal delay time (PDT) and penetration-aspiration scale (PAS) were measured and the changes among the different volumes were analyzed.ResultsPDTs were shortened significantly when 5 mL and 10 mL of thin barium were swallowed compared to 2 mL. However, there was no significant difference in PAS as the bolus volume increased.ConclusionThe increased fluid bolus volume reduced the pharyngeal delay time, but did not affect the penetration and aspiration status.

Thickness effects in barium hexaferrite films deposited by magnetron sputtering

In this work, barium ferrite films were deposited onto sapphire substrates by radio frequency magnetron sputtering. A thin amorphous barium ferrite film of about 20 nm was deposited at low temperature as a buffer layer. Barium ferrite films with thicknesses of 100 nm, 1 μm and 8 μm have been prepared. The results show that the 8-μm-thick barium ferrite films have no cracks whereas the barium ferrite films without amorphous buffer layer break and peel off. The barium ferrite films with a thickness of 100 nm show good c-axis orientation and strong magnetic anisotropy. The c-axis orientation deteriorates, and the magnetic anisotropy disappears gradually with the increase of the thickness of the barium ferrite films. The barium ferrite films with a thickness of 8 μm orientate randomly and show magnetic isotropy. The thickness effects may be explained by the increase of the random nucleation sites.

On-wafer magnetically tunable millimeter wave notch filter using M-phase Ba hexagonal ferrite/Pt thin films on Si

A prototype of a fully integrated on-wafer, magnetically tunable band-stop filter operating at millimeter wave frequencies is demonstrated on a Si substrate. In contrast to earlier studies, the filter uses a very thin barium hexagonal ferrite film incorporated into the dielectric layer of a microstrip transmission line to filter the signal. The zero-field operational frequency is about 34 GHz, increasing linearly with the strength of a static, perpendicularly applied magnetic field at a rate of about 2.7 GHz/kOe. Experimentally, high signal attenuation (33–67 dB/cm) at the resonance frequency and insertion losses as low as 4.5 dB were simultaneously observed, while the 3 dB device bandwidths were generally below 1 GHz. Our calculations are in quantitative agreement with the experimental results. We also find an important result that the thickness and conductivity of the Pt ground plane plays a key role in insertion losses, indicating directions for further improvements.

A strong electro-optically active lead-free ferroelectric integrated on silicon

The development of silicon photonics could greatly benefit from the linear electro-optical properties, absent in bulk silicon, of ferroelectric oxides, as a novel way to seamlessly connect the electrical and optical domain. Of all oxides, barium titanate exhibits one of the largest linear electro-optical coefficients, which has however not yet been explored for thin films on silicon. Here we report on the electro-optical properties of thin barium titanate films epitaxially grown on silicon substrates. We extract a large effective Pockels coefficient of r(eff) = 148 pm V(-1), which is five times larger than in the current standard material for electro-optical devices, lithium niobate. We also reveal the tensor nature of the electro-optical properties, as necessary for properly designing future devices, and furthermore unambiguously demonstrate the presence of ferroelectricity. The integration of electro-optical active films on silicon could pave the way towards power-efficient, ultra-compact integrated devices, such as modulators, tuning elements and bistable switches.