bluuebunny/crossref_metadata_2025 huggingface dataset:
Difference between Pharmacist-Obtained and Physician-Obtained Medication Histories in the Intensive Care Unit
Authors: Hatch Jacob , Becker Tara , Fish Jeffrey T.
Published: April 2011

Purpose

To quantify the differences between medication histories obtained by physicians and pharmacists from critically ill patients in the intensive care unit (ICU) and to identify patient types at greatest risk of medication errors.

Methods

Retrospective medical record review of 200 consecutively admitted critically ill patients to the medical/surgical ICU of a university-affiliated hospital. The pharmacist-obtained medication history was compared to the physician-obtained medication history. Variations assessed included the number of drugs identified, drug name, drug formulation, dose, and frequency of administration. Inpatient medication orders were reviewed to obtain the number and accuracy of home medications prescribed in the ICU. Patients were divided into predefined groups: trauma, medical, and nontrauma surgical to assess the risk of medication error by patient type.

Results

Pharmacists and physicians identified a total of 981 and 665 medications, respectively. The mean (± SD) number of home medications per history was 4.2 (±4.9) for physicians and 6.2 (±5.7) for pharmacists ( P < .0001). Physician-obtained medication histories contained 1,628 variances relative to the pharmacist-obtained medication histories. The variances by type included the frequency of administration, 37%; drug dose, 34.6%; missing drugs, 22.3%; extra drugs, 3.6%; and drug formulation, 2.5%. Thirty-nine patients received continuation of their home medications in the ICU totaling 97 orders (9.9% of home medications identified by pharmacists). Thirty of these orders varied from the pharmacy history and 27 were subsequently corrected. Conclusion. Pharmacists identified more home medications than physicians when obtaining a medication history in the ICU. This may improve the accuracy of home medications ordered in the ICU.
Acetaminophen Intravenous
Authors: Cada Dennis J. , Levien Terri L. , Baker Danial E.
Published: April 2011

Each month, subscribers to The Formulary Monograph Service receive 5 to 6 well-documented monographs on drugs that are newly released or are in late phase 3 trials. The monographs are targeted to Pharmacy & Therapeutics Committees. Subscribers also receive monthly 1-page summary monographs on agents that are useful for agendas and pharmacy/nursing in-services. A comprehensive target drug utilization evaluation/medication use evaluation (DUE/MUE) is also provided each month. With a subscription, the monographs are sent in print and are also available on-line. Monographs can be customized to meet the needs of a facility. Subscribers to The Formulary Monograph Service also receive access to a pharmacy bulletin board, The Formulary Information Exchange (The F.I.X.). All topics pertinent to clinical and hospital pharmacy are discussed on The F.I.X. Through the cooperation of The Formulary, Hospital Pharmacy publishes selected reviews in this column. For more information about The Formulary Monograph Service or The F.I.X., call The Formulary at 800-322-4349. The April 2011 monograph topics are on vilazodone hydrochloride, hydroxyprogesterone caproate, gabapentin extended-release, spinosad 0.9% topical suspension, and aclidinium bromide. The DUE/MUE is on pegloticase.
Some mathematical problems of acoustic probing
Authors: Anikonov Yurii Evgenievich , Kovtanyuk Andrey Egorovich , Neshchadim Mikhail Vladimirovich
Published: April 2011

In this work some mathematical problems of acoustic probing are considered. The most attention is focused on problems of determination of shape of radiating objects. Methods of determination of diffusers characteristics are proposed and discussed.
Determination of physical and geometrical characteristics of layered inhomogeneous elastic medium
Authors: Bogulskii I. O. , Volchkov Yu. M.
Published: April 2011

The article contains an exposition of the basic idea of construction of numerical algorithms based upon the several local approximations by linear polynomials for every sought-for function of dynamic problems of solids. We discuss also some problems of determination of physical and geometrical characteristics of layered inhomogeneous medium.
On a class of finite difference methods for ill-posed Cauchy problems with noisy data
Authors: Bakushinsky Anatoly B. , Kokurin Mikhail Yu. , Kokurin Mikhail M.
Published: April 2011

We consider a class of finite difference schemes for approximating solutions to ill-posed Cauchy problems for first order linear operator differential equations in a Hilbert space. Both the operator and the initial state in the problems are supposed to be noisy. Using an appropriate coordination between the mesh width and error levels, we improve previous error estimates for approximations generated by the schemes.
Numerical algorithm for two-dimensional inverse acoustic problem based on Gel'fand–Levitan–Krein equation
Authors: Kabanikhin Sergey I. , Shishlenin Maxim A.
Published: April 2011

The inverse problem for the acoustic equation is considered. We propose a method of reconstruction of the density approximating 2D inverse acoustic problem by a finite system of one dimensional inverse acoustic problems. The 2D analogy of the Gel'fand–Levitan–Krein method is established. The inverse acoustic problem is formulated and the short outline of the history and development in this field are given in Section 1. In Section 2 we consider the 2D analogy of the Gel'fand–Levitan–Krein equation. The N-approximation of the Gel'fand–Levitan–Krein equation is obtained for inverse acoustic problem in Section 3. The numerical results are presented in Section 4.
Methodische Aspekte zur Bestimmung der Testosteronkonzentration als Biomarker der Gesundheit des Mannes/Challenges in the measurement of serum testosterone concentrations as a biomarker of men's health
Authors: Haring Robin , Spielhagen Christin , Nauck Matthias
Published: April 2011

Die Bestimmung der Testosteronkonzentration im Serum steht in den letzten Jahren zunehmend im Fokus der Andrologie. Zahlreiche Beobachtungsstudien präsentierten Zusammenhänge zwischen niedrigen Serum Testosteronkonzentrationen und inzidenten kardiovaskulären Risikofaktoren bzw. erhöhtem Mortalitätsrisiko. Darüber hinaus sind niedrige Serum Testosteronkonzentrationen ein entscheidendes diagnostisches Kriterium des Altershypogonadismus. Aufgrund ihrer hohen Validität und Messfrequenz ersetzen massenspektroskopische Verfahren zunehmend die bisher gebräuchlichen Immunoassays zur Testosteronmessung, und werden als „Goldstandard“ zur Sexualhormonmessung diskutiert. Der Artikel stellt verschiedene Einflussfaktoren der Bestimmung der Testosteronkonzentration vor und gibt praktische Hinweise für die Interpretation der Ergebnisse.
Multizentrische Ermittlung von Referenzbereichen für Parameter des maschinellen Blutbildes/Multicentric Determination of Reference Ranges for Automated Blood Counts
Authors: Nebe Thomas , Bentzien Frank , Bruegel Mathias , Fiedler Georg Martin , Gutensohn Kai , Heimpel Hermann , Krebs Nicole , Ossendorf Manfred , Schuff-Werner Peter , Stamminger Gudrun , Baum Hannsjörg
Published: April 2011

Das kleine bzw. große Blutbild sind die am häufigsten durchgeführten Laboruntersuchungen und sind immer noch wesentlicher Bestandteil in der Einordnung von primären oder sekundären Störungen des blutbildenden Systems. Die Interpretation der Befunde basiert auf dem Vergleich mit altersentsprechenden Referenzbereichen, wenngleich in vielen Fällen ein Vergleich mit patienteneigenen Vorwerten genauere Aussagen erlaubt.

Mit dem Ziel der Ermittlung von Alters-, Geschlechts- und Geräte-spezifischen Referenzbereichen wurden in der vorliegenden multizentrischen Studie bei 1158 gesunden Männern und Frauen im Alter von 16 bis 75 Jahren große Blutbilder mit aktuell in der Routinediagnostik eingesetzten Hämatologiesystemen analysiert. Die Probandenrekrutierung erfolgte im Rahmen von personalärztlichen Untersuchungen oder Blutspenden, wobei neben der routinemäßig durchgeführten Untersuchung eine zusätzliche Selbstauskunft mittels standardisiertem Fragebogen erfolgte. Es wurden Referenzwertbereiche für das kleine Blutbild, das Differenzialblutbild sowie die Retikulozytenzahl erhoben.

Für eine Reihe von Messgrößen ergaben sich Alters-, Geschlechts- und Geräte-spezifische Unterschiede, beispielsweise konnten wir eine Reduktion der Erythrozytenkonzentration, eine Zunahme von MCH und MCV sowie der Basophilenzahl mit zunehmendem Lebensalter zeigen. Dieser Befund könnte für die Einordnung von hämatologischen Erkrankungen des älteren Menschen wie den myeloproliferativen Neoplasien (MPN/CMPE) und Myelodysplasien (MDS) von Bedeutung sein. Geschlechtsabhängigkeiten konnten wir für die Erythrozyten- und Hämoglobinkonzentration, den Hämatokrit, den MCHC, die Retikulozytenzahl, die Thrombozytenzahl sowie die Leukozyten zeigen. Für die Thrombozytenzahl, die Leukozytenzahl sowie der neutrophilen und lymphatischen Subpopulation ergaben sich signifikant höhere Werte, für die anderen genannten niedrigere Werte bei weiblichen Probanden. Bei Rauchern ergaben sich höhere Leukozytenzahlen, die insbesondere auf höheren Neutrophilen- bzw. Lymphozytenzahlen beruhen. Gegenüber Angaben in Vorarbeiten war dieser Effekt jedoch deutlich geringer ausgeprägt. Der multizentrische Ansatz in dieser Studie ist erwartungsgemäß mit einer größeren Streuung der Blutbildbefunde assoziiert, sollte die Übertragbarkeit der Ergebnisse auf verschiedene Zentren jedoch erleichtern.
Multi-centric determination of reference ranges for automated blood counts1
Authors: Nebe Thomas , Bentzien Frank , Bruegel Mathias , Fiedler Georg Martin , Gutensohn Kai , Heimpel Hermann , Krebs Nicole , Ossendorf Manfred , Werner Peter-Schuff , Stamminger Gudrun , Baum Hannsjörg
Published: April 2011

The analysis of blood cell count including differential, is the most frequent laboratory test and has still essential diagnostic value in the diagnosis of primary or secondary diseases of the hematopoietic system. The interpretation is based on a comparison with age matched reference intervals, despite the fact that a comparison with the patients own preceding values allows a more precise statement. In the present study, blood counts and differential were performed in 1158 healthy males and females with an age ranging from 16 to 75 years were investigated using current hematology systems. The donors were examined by personnel physicians and those examining blood donors in transfusion medicine and in addition were asked via standardized questionnaire. The study resulted in reference ranges for the complete blood count, the differential blood count and reticulocytes. For several analytes, age-, gender- or analyzerspecific reference ranges were obtained. We found an age dependent decrease of the erythrocyte concentration and an increase for MCH and MCV as well as for basophils. These findings could be important for the diagnosis of diseases of the elderly like like myeloproliferative diseases (MPN) and myelodysplasias (MDS). Gender specific changes could be shown for the hemoglobulin-, the erythrocyte- and reticulocyte concentration, as well as for hematocrit and MCHC, being reduced in females. On the other hand, females showed significant higher levels for platelets and leukocytes, based on an increase of neutrophils and lymphocytes. The leukocytosis of smokers was confirmed for neutrophils and lymphocytes but lower than one could expect from recent studies. A multicentric study shows a broader distribution compared to unicentric data but this probably better reflects the reality and improves the applicability of the reference ranges.
Spermatogenic and sperm quality differences in an experimental model of metabolic syndrome and hypogonadal hypogonadism
Authors: Mallidis Con , Czerwiec Agnieszka , Filippi Sandra , O'Neill Jason , Maggi Mario , McClure Neil
Published: April 2011

The synergistic effect of the co-morbidities that comprise metabolic syndrome (MetS) is increasingly being recognised as an important contributor in the pathology of a broad spectrum of seemingly disparate conditions. However, in terms of male reproductive function, beyond erectile dysfunction, little is known about the influence of this cohort (collectively or separately) on spermatogenesis and sperm quality. The aims of this study were to assess the reproductive tract of a MetS animal model for detrimental changes, to determine whether a group of compounds (advanced glycation end products and their receptor) known to cause cell dysfunction and DNA damage was present and assess whether hypogonadotropic hypogonadism was the main contributing factor for the changes seen. Animals fed a high-fat diet were found to have significantly increased cholesterol, triglycerides, blood glucose, mean arterial pressure and visceral fat levels. Although serum testosterone was decreased, no changes were seen in either testicular or epididymal histology. Immunolocalisation ofNϵ-carboxymethyl-lysine and the receptor for advanced glycation end products was found in the testes, epididymides and sperm of the two treated groups of animals; however, ELISA did not show any difference in protein levels. Similarly, assessment of sperm nuclear DNA (nDNA) fragmentation by acridine orange test did not find significant differences in nDNA integrity. We conclude that the minimal effect on spermatogenesis and sperm quality seen in our model is probably due to the moderate increase of blood glucose rather than the hypogonadism.
Pulmonary Nodules in a Newborn With ATP-Binding Cassette Transporter A3(ABCA3)Mutations
Authors: Uchida Derek A. , Wert Susan E. , Nogee Lawrence M. , Carroll Travis R. , Chatfield Barbara A.
Published: April 2011

Mutations in the gene for adenosine triphosphate–binding cassette transporter A3 (ABCA3) have been reported in infants and children with fatal surfactant deficiency and interstitial lung disease. Previously reported radiographic lung findings include ground-glass opacification, streaky infiltrates, and interstitial septal thickening. We report here the unusual case of a newborn who rapidly developed large rounded masses in the lung soon after birth that then resolved spontaneously by 3 months of age. She was found to be a compound heterozygote for both a known and a novel mutation in the ABCA3 gene. This report underscores the diverse clinical presentation of this condition.
Efficacy of Proton-Pump Inhibitors in Children With Gastroesophageal Reflux Disease: A Systematic Review
Authors: van der Pol Rachel J. , Smits Marije J. , van Wijk Michiel P. , Omari Taher I. , Tabbers Merit M. , Benninga Marc A.
Published: April 2011

INTRODUCTION:

Use of proton-pump inhibitors (PPIs) for the treatment of gastroesophageal reflux disease (GERD) in children has increased enormously. However, effectiveness and safety of PPIs for pediatric GERD are under debate.

OBJECTIVES:

We performed a systematic review to determine effectiveness and safety of PPIs in children with GERD.

METHODS:

We searched PubMed, Embase, and the Cochrane Database of Systematic Reviews for randomized controlled trials and crossover studies investigating efficacy and safety of PPIs in children aged 0 to 18 years with GERD for reduction in GERD symptoms, gastric pH, histologic aberrations, and reported adverse events.

RESULTS:

Twelve studies were included with data from children aged 0–17 years. For infants, PPIs were more effective in 1 study (compared with hydrolyzed formula), not effective in 2 studies, and equally effective in 2 studies (compared with placebo) for the reduction of GERD symptoms. For children and adolescents, PPIs were equally effective (compared with alginates, ranitidine, or a different PPI dosage). For gastric acidity, in infants and children PPIs were more effective (compared with placebo, alginates, or ranitidine) in 4 studies. For reducing histologic aberrations, PPIs showed no difference (compared with ranitidine or alginates) in 3 studies. Six studies reported no differences in treatment-related adverse events (compared with placebo or a different PPI dosage).

CONCLUSIONS:

PPIs are not effective in reducing GERD symptoms in infants. Placebo-controlled trials in older children are lacking. Although PPIs seem to be well tolerated during short-term use, evidence supporting the safety of PPIs is lacking.
Thromboprophylaxis in a Pediatric Hospital: A Patient-Safety and Quality-Improvement Initiative
Authors: Raffini Leslie , Trimarchi Tara , Beliveau Johanna , Davis Daniela
Published: April 2011

OBJECTIVES:

Venous thromboembolism (VTE) prophylaxis for patients at risk is often overlooked in pediatric health care institutions, which provides an opportunity to improve patient care. The objectives of this study were to review our current hospital practice, identify a population at high risk, and formulate institutional guidelines for thromboprophylaxis.

METHODS:

This was a prospective patient-safety and quality-improvement project performed at a large pediatric tertiary care hospital. We developed criteria for assessing risk and selecting prophylactic intervention through analysis of the age distribution and underlying medical conditions of patients with VTE at our center, literature review of adult recommendations for thromboprophylaxis, and consensus opinion of multiple specialists at our institution. A patient-care policy was developed to assess VTE risk and prescribe the appropriate thromboprophylaxis regimen. The primary outcome measure was compliance with thromboprophylaxis guidelines in patients at risk for VTE.

RESULTS:

Over the 4-year study period, the observed rate of VTE prophylaxis in patients at risk increased from a baseline of 22% to an average rate of 82%, and there were intermittent improvements up to 100%.

CONCLUSIONS:

Although some of the details may vary from center to center, many of the discussed principles and practices involved in instituting a VTE-prevention program are applicable to other pediatric institutions. Despite the fact that the risk of VTE in hospitalized children is much lower than that in adults, there are patients in pediatric hospitals who deserve systematic screening and thoughtful application of preventative measures.
A Systematic Review of Medical Treatments for Children With Autism Spectrum Disorders
Authors: McPheeters Melissa L. , Warren Zachary , Sathe Nila , Bruzek Jennifer L. , Krishnaswami Shanthi , Jerome Rebecca N. , Veenstra-VanderWeele Jeremy
Published: April 2011

CONTEXT:

As many as 1 in every 110 children in the United States has an autism spectrum disorder (ASD). Many medical treatments for ASDs have been proposed and studied, but there is currently no consensus regarding which interventions are most effective.

OBJECTIVE:

To systematically review evidence regarding medical treatments for children aged 12 years and younger with ASDs.

METHODS:

We searched the Medline, PsycInfo, and ERIC (Education Resources Information Center) databases from 2000 to May 2010, regulatory data for approved medications, and reference lists of included articles. Two reviewers independently assessed each study against predetermined inclusion/exclusion criteria. Studies of secretin were not included in this review. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes and assigned overall quality and strength-of-evidence ratings on the basis of predetermined criteria.

RESULTS:

Evidence supports the benefit of risperidone and aripiprazole for challenging and repetitive behaviors in children with ASDs. Evidence also supports significant adverse effects of these medications. Insufficient strength of evidence is present to evaluate the benefits or adverse effects for any other medical treatments for ASDs, including serotonin-reuptake inhibitors and stimulant medications.

CONCLUSIONS:

Although many children with ASDs are currently treated with medical interventions, strikingly little evidence exists to support benefit for most treatments. Risperidone and aripiprazole have shown benefit for challenging and repetitive behaviors, but associated adverse effects limit their use to patients with severe impairment or risk of injury.
The potential role of SPECT/CT in the preoperative detection of sentinel lymph nodes in breast cancer
Authors: Mátrai Zoltán , Tóth László , Saeki Toshiaki , Sinkovics István , Gődény Mária , Takeuchi Hideki , Bidlek Mária , Bartal Alexandra , Sávolt Ákos , Dorogi Bence , Kásler Miklós
Published: April 2011

Regional lymph node status is the most important prognostic factor in breast cancer. Sentinel lymph node biopsy is the standard method of axillary staging in early breast cancer patients with clinically negative nodes. Preoperative lymphoscintigraphy might support refining biopsy findings by determining the number and location of sentinel lymph nodes. In aged or overweight patients, in the presence of atypical or extra-axillary lymphatic drainage, non-visualized lymph nodes, or sentinel lymph nodes close to the isotope injection site, detection could be aided by a new, hybrid imaging tool: the single-photon emission computed tomography combined with computed tomography (3D SPECT/CT). For the first time in Hungarian language, authors overview the literature: all 14 English-language articles on the implementation of 3D SPECT/CT in sentinel lymph node detection in breast cancer are included. It is concluded that 3D SPECT/CT increases the success rate and quality of preoperative sentinel node identification, and is capable of providing a more accurate staging of breast cancer patients in routine clinical practice. Orv. Hetil., 2011, 152, 678–688.
Comprehensive examination of somatic oncogene mutation in normal and pathologic thyroid tissues
Authors: Tóbiás Bálint , Balla Bernadett , Kósa P. János , Horányi János , Takács István , Bölöny Eszter , Halászlaki Csaba , Nagy Zsolt , Speer Gábor , Járay Balázs , Székely Eszter , Istók Roland , Lakatos Péter
Published: April 2011

It is established that numerous somatic oncogene mutation (BRAF, NRAS, HRAS, KRAS) and gene translocations (RET/PTC, PAX8/PPAR-gamma) are associated with the development of thyroid cancer. In this study 22 intraoperative thyroid tissue samples (11 pathologic and 11 normal) were examined. Somatic single nucleotide polymorphisms were analyzed by LigthCycler melting method, while translocations were identified by real-time polymerase chain reaction technique. In tumorous sample 3 BRAF, 2 NRAS and one HRAS mutations were found, as well as one RET/PTC1 translocation. Results confirm international data showing that these oncogene mutations and translocations are linked to thyroid cancer. Cytological examination completed with genetic data may support the diagnosis of thyroid malignancies. In addition, genetic alterations may indicate malignant transformation and may become prognostic factors in future. Orv. Hetil., 2011, 152, 672–677.
Two-step Sintering Process for Lutetium Oxide Transparent Ceramics
Authors: Guo Xiaomei , Li Kewen K. , Wang Yanyun , Zou Yingyin K. , Jiang Hua
Published: April 2011

During a two-step sintering practice, important factors such as final grain sizes and residual pore status can be controlled through adjusting the first and second step sintering temperatures and durations. Moreover, the sintering temperatures (both the first and the second step) can be several hundred degrees lower than those in a traditional sintering process to obtain fully dense ceramics. Therefore, it is a potentially cost-effective preparation procedure for ceramics with fine grains. In this work, we successfully demonstrated the synthesis of aggregate-free sesquioxide nanometer-sized powders with a narrow size distribution through a modified chemical co-precipitation process. Subsequently, ytterbium-doped Lu2O3 ceramics of near full density were obtained through a two-step sintering process.
Facile synthesis of polypyrrole/graphene nanosheet-based nanocomposites as catalyst support for fuel cells
Authors: Saner Burcu , Gürsel Selmiye Alkan , Yürüm Yuda
Published: April 2011

The integration of catalyst metals into the graphene-based composites can be a new way to ensure thermal and electronic conductivities of the catalyst support materials in polymer electrolyte membrane fuel cells. In this work, graphene nanosheets were synthesized via a mild and safer chemical route including three major steps: graphite oxidation, ultrasonic treatment and chemical reduction. Then, polypyrrole was coated on graphene nanosheets by in-situ polymerization to fabricate polypyrrole/graphene nanosheet-based nanocomposites as the catalyst supports. Pt nanoparticles were uniformly dispersed on the surface of nanocomposites by sonication technique.
Process Optimization for Nanocrystalline Cellulose Production from Microcrystalline Cellulose
Authors: Danumah Christophe , Fenniri Hicham
Published: April 2011

A process optimization has been developed for obtaining nanocrystalline cellulose (NCC) by acid hydrolysis of commercially available microcrystalline cellulose (MCC) in high yield (~ 40-50%). This method was based on control of key parameters such as the rate of addition of sulfuric acid solution to the MCC/water suspension, the mixing speed, the volume of collected NCC suspensions and the volume ratio of NCC suspension to water during dialysis. The resulting NCC products were characterized by x-ray diffraction (XRD), thermogravimetric analysis (TGA), elemental analysis (EA), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Electron microscopy results showed that the rod-shaped NCC had lengths and widths of about 40-400 nm and 5-40 nm, respectively.
Graphitic Carbon Nanoparticles from Asphaltenes
Authors: Danumah Christophe , Myles Andrew J. , Fenniri Hicham
Published: April 2011

We report preliminary studies on the preparation of carbon nanoparticles (CNPs) of ~ 20 nm in diameter derived from asphaltenes under mild conditions. This transformation occurred upon heating a thin film of asphaltenes cast on a carbon coated copper grid under both nitrogen and oxygen atmosphere. The resulting CNPs were characterized by thermogravimetric analysis (TGA), scanning/transmission electron microscopy (SEM/STEM), transmission electron microscopy (TEM), elemental analysis (EA) and Auger electron spectroscopy (AES). The findings point towards asphaltenes, a crude oil by-product, as a potential source for carbon nanomaterials.
Scanning Thermal Lithography as a Tool for Highly Localized Nanoscale Chemical Surface Functionalization
Authors: Duvigneau Joost , Schönherr Holger , Vancso G. Julius
Published: April 2011

We report on Scanning Thermal Lithography (SThL), a recently introduced lithographic tool, for local thermochemistry on tert-butyl acrylate based polymer films featuring chemical cross links. The tailored polymer films afford platforms for controlled high molecular density coupling and surface immobilization of biologically relevant molecules, such as proteins. The thermally labile tert-butyl ester groups in tert-butyl acrylate based polymer films can be cleaved in air at temperatures above 150 °C to yield carboxylic acid functional groups for further (bio)- conjugation. The films were optimized to avoid plastic deformation at the elevated temperatures used during SThL. Exploiting these properties patterns with length scales as small as 35 ± 6 nm have been successfully thermally activated with SThL. Hence SThL comprises an attractive approach for the development of e.g. (bio)sensors and platforms for cell surface interaction studies with nanoscale patterns.
Study of Selectively Permeable Coatings to Textiles
Authors: Sargent Joseph G. , Lee Jun S. , Reynaud Emmanuelle , Gilbert Michael D. , Sloan James M.
Published: April 2011

Breathable barrier textiles for both chemical agent and moisture are being actively developed for military and industrial applications. An ideal approach is to coat textiles with a semi-permeable film that allows the transport of water while still serving as a barrier for chemical agents. Sulfonated poly (styrene-block-isobutylene-block-styrene) (SIBS) copolymer spontaneously phase separates upon drying from solution to produce a nanostructured film with the controlled barrier functionality for water permeation and repelling of chemical agents.

The objective of this research is to investigate coating uniformity and phase morphology of SIBS coating materials fabricated by novel solvent combinations. Scanning electron microscopy analysis is used for the assessment of the coating uniformity as well as the level of adhesion between the polymer coating and fabric substrate. Transmission electron microscopy is used to characterize the phase separation morphology of the SIBS copolymer coating. The mechanical behavior of the coated fabric is determined through tensile and shear tests and is compared to the bare fabric behavior. The goal of this study is to relate the processing conditions of the final nanostructured block copolymer coated fabric produced on industrial scale.
Assembly of Nanoparticles from Bioactive Peptides and Chitosan
Authors: Hu B. , Huang Q. R. , Zeng X. X.
Published: April 2011

Assembly of nanoparticles from bioactive peptides, caseinophosphopeptides (CPPs) and chitosan (CS) at physiological conditions and various CS/CPPs mass ratios have been systematically studied using a combination of turbidimetric titration, dynamic light scattering (DLS), electrophoretic mobility (zeta-potential) and transmission electron microscopy (TEM). Peptides, incorporated with CS forming nanoparticles, have already been prepared and identified using liquid chromatography-tandem mass spectrometry (LC-MS-MS). They are characteristic with different amount of clusters of phosphorylated seryl residues. At low salt concentration, an increase of CS/CPP mass ratio shifted the critical pHϕ1, which designated the formation of CS/CPP nanocomplexes, as well as pHmax, representing the neutralization of positive and negative charge to higher pH values. The peptide-polymer binding mechanism was analyzed according to the results of DLS, electrophoretic mobility, and TEM. First, negatively charged CPPs absorbed to positively charged CS molecular chain to form intrapolymer nanocomplexes saturated with CPPs (CPPNP). Then, the negatively charged CPPNP was bridged by added positively charged CS. Finally, novel nano-scaled spherical brushes were formed as additional CS molecule absorbed back to and bound the CPPNP. Phosphorylated groups in the CPPs might be the dominant sites for interaction with –NH3+ on the CS molecular chain.
High Gain, Silicon-on-insulator Photodetector with Multiple Gates and a Nanowire Based Narrow-wide-narrow Channel
Authors: Roudsari Anita Fadavi , Saini Simarjeet S. , O Nixon , Anantram M. P.
Published: April 2011

We propose a phototransistor geometry that incorporates silicon nanowires (SiNW) in the device channel. A set of two gates controls the charge flow inside the NW. This improves the device photo-response more than 10x when compared with a single gate phototransistor, leading to a photo-responsivity of greater than 104(A/W), while the dark properties of both devices are similar.
A Novel High-Dynamic a-Si:H Multicolor pin-Detector with ZnO:Al Front and Back Contacts
Authors: Bablich Andreas , Watty Krystian , Merfort Christian , Seibel Konstantin , Boehm Markus
Published: April 2011

Conventional silicon sensors provide insufficient capability for color reproduction by producing three color signals (RGB) to fit their pixel sensitivities to that of the human eye. Photo detector devices based on a-SiC:H and a-SiGe:H offer the opportunity to shift spectral sensitivity continuously by varying external bias voltages. Based on the measurement results of Rieve et al. [2] we determined the absorption coefficients of a group of a-SiC:H and a-SiGe:H layers to simulate the penetration depth of photons at different energies into the device structure [3]. Knowing the indices of absorption, refraction and extinction, it is possible to engineer diodes in such a way that accumulations of charge carriers are generated at varying device depths. The use of common chromium (Cr) cathodes avoids a sharp falling edge of the sensitivity towards longer wavelengths. The use of low reflective and highly conductive aluminum-doped zinc oxide (ZnO:Al) as a material for the back contact of the diodes suppresses Fresnel reflections and has been verified experimentally. A dynamic range of more than 100 dB at 1000 lux could be obtained by I-/V- measurements of a-Si:H pin diodes fabricated between two ZnO:Al contacts. Optically the detectors show maxima between 440 nm and 630 nm with reduced Fresnel reflections and a very low leakage current of 10-8A/cm2 at -5 V bias voltage. Present research efforts concentrate on the verification of the optical properties and exact thicknesses of the chosen layers as well as on the development of a front and back illumination device structure which ensures a continuous spectral shift of the photosensitivity. This work requires extensive bandgap engineering and offers good prospects to improve security imaging tools as well as chemical analysis systems.
A Chemical Gas Sensor from Large-Scale Thermal CVD Derived Graphene
Authors: Song Xiaojuan , Wagner Brent , Kang Zhitao
Published: April 2011

Large-scale graphene sheets were grown on thin nickel film coated Si substrates using a reliable and repeatable thermal Chemical Vapor Deposition (CVD) technique. The graphene films were then transferred onto a SiO2 coated Si wafer to fabricate a 5 mm x 5 mm resistive sensor structure. Raman spectroscopy analysis confirmed the existence of graphene. Preliminary sensing results were demonstrated by the detection of hazardous gases such as NO2 and MMH (mono-methyl hydrazine). Characterization of the device channel resistivity (switching response) was conducted as a function of the analyte type and concentration. The sensor response indicates a charge transfer mechanism between the analytes and graphene.
Evaluation of Graphene and Graphene Derivatives for RF-Impedance Based Sensing
Authors: Xing Yun , Huang Hong , Zhuang Yan
Published: April 2011

Graphene and its derivatives have attracted much attention for potential applications in biological sensing systems because of their unique 2D structural, surface and electronic properties. Reports on graphene - based electrochemical impedance biosensors are emerging rapidly. In this research, we have explored the RF (radio frequency) impedance –based sensing feasibility of graphene and graphene derivative materials on the coplanar waveguide (CPW) device. The transmission line based sensing experiments demonstrated clear and significant blueshifts of resonance frequencies and decrease of the resistance at and beyond resonance frequencies after graphene oxide is absorbed with DNA. The results may lead to an alternative approach in developing graphene based chemical and biosensors.
Ceramic Thin Films for High Integration Density Capacitor Applications
Authors: Taroata Dan , Cheema Tarik A. , Fischer Wolf-Joachim , Garnweitner Georg , Schmid Guenter
Published: April 2011

We report a novel concept for the direct integration of capacitors in printed circuit boards using ultra-small BaTiO3 and ZrO2 nanoparticles prepared by a chemical method. Electrical properties comparable to surface mount ceramic capacitors were achieved by proper processing of the nanoparticles, achieving a device-yield of >90% under research environment. The loss factor of the presented integrated capacitors does not exceed 0.05 independent of frequency, capacitor’s electrode area or applied bias voltage.
Quantum rods and dots-based structures & devices: Low cost aqueous synthesis and bandgap engineering for solar hydrogen and solar cells applications
Authors: Vayssieres Lionel
Published: April 2011

If one considers the largest and geographically balanced free natural resource available on Earth, that is seawater, and that more sunlight energy is striking our blue planet in one hour than all of our annual energy consumption, the direct solar-to-hydrogen conversion by photo-oxidation of seawater is a very straightforward and attractive solution for the production of hydrogen, as it is clean, sustainable and renewable. It offers an alternative solution to fossil-fuel-based energy sources and explains the tremendous interest in renewable, sustainable energy sources and materials for energy conversion. However, the materials requirements for water splitting and thus the direct solar-to-hydrogen generation are drastic. The materials must be stable in water, which rules out many classes of materials. They must also be stable under illumination against photocorrosion and their bandgap must be small enough to absorb visible light, but large enough not to “dissolve” once illuminated. Finally, their band edges must be positioned below and above the redox potential of hydrogen and oxygen, respectively. Bandgap energy and band-edge positions, as well as the overall band structure of semiconductors are of crucial importance in photoelectrochemical and photocatalytic applications. The energy position of the band edges can be controlled by the electronegativity of the dopants and solution pH, as well as by new concepts such as quantum confinement effects and the fabrication of novel hetero-nanostructures. Fulfilling those requirements while keeping the cost of the materials low is a tremendously difficult challenge, which explains why solar hydrogen generation is still in its infancy. Novel approach and latest development combining low cost aqueous synthesis techniques, vertically oriented metal oxide nanorods and quantum confinement effects probed by x-ray spectroscopies from synchrotron radiation is presented leading to stable and cost-effective visible-light-active semiconductors for seawater splitting, the holy grail of photocatalysis.
Preparation and Characterization of Nanostructured Silicon for Optoelectronic Applications
Authors: Ryu Y. S. , Filios A. , Paek Y. , Ryu S.
Published: April 2011

Silicon is by far the most successful material in the microelectronics industry enjoying a well-established fabrication and processing infrastructure. Two of the main challenges in traditional silicon electronic devices are (a) silicon’s relatively small and indirect fundamental energy band-gap, which severely limits optoelectronic applications, and (b) the absence of a suitable material to form a heterojunction barrier on silicon. Silicon based nanostructures are being explored as potential candidates to extent the applications of silicon in optoelectronics, provide for high-speed silicon quantum devices, increase the efficiency and reduce the cost in silicon photovoltaic solar cells, and facilitate cost-effective silicon sensors for biological, environmental, and other applications. Quantum size silicon nanolayers, nanowires, and nanodots embedded in oxide, nitride, and other amorphous matrices may provide an effective barrier for silicon, as well as band-gap engineering and enhanced optical transitions for solar cell and optoelectronic applications.
What is the true nature of conducting proton in perovskite ceramic membrane: hydroxyl ion or interstitial proton ?
Authors: Slodczyk Aneta , Colomban Philippe , Zaafrani Oumaya , Lacroix Olivier , Loricourt Johan , Grasset Frederic , Sala Beatrice
Published: April 2011

The proton conducting perovskites are widely investigated due to their high potential as electrolyte membranes of fuel cells, water steam electrolysers and CO2/syngas converters. Our comprehensive spectroscopic (Raman, IR, neutron), thermogravimetric, elastic and quasi-elastic neutron diffusion as well as conductivity studies performed on Ln/RE- modified zirconate ceramics with controlled densification (90-99% of theoretical density) reveal the important differences between the surface and bulk protonic species. The results clearly show that trivialization of the protonation process complexity can favorite the adsorption of the surface protonic species (hydroxide, hydrocarbonates, etc), prohibit the incorporation of bulk protons, i.e. species responsible for the proton conduction and confuse the understanding of fundamental aspects concerning the proton conductors such as the true nature of conducting species. Our studies reveal that OH- ions are located at the surface of poor densified ceramic and the bulk conducting protons exhibit an ionic, free of covalent-bonded nature.
Raman spectrum of group IV nanowires: influence of temperature
Authors: Anaya J. , Prieto C. , Souto J. , Jiménez J. , Rodríguez A. , Sangrador J. , Rodríguez T.
Published: April 2011

Group IV semiconductor nanowires are characterized by Raman spectroscopy. The results are analyzed in terms of the heating induced by the laser beam on the nanowires. By solving the heat transport equation one can simulate the temperature reached by the NWs under the exposure to a laser beam. The results are illustrated with Si and Si1-xGex nanowires. Both bundles of nanowires and individual nanowires are studied. The main experimental conditions contributing to the nanowire heating are discussed.
Catalytic activity of nanostructured plate-type Cu-based on ZnO nanorods promoted by additive metals for oxidative steam reforming of methanol
Authors: Li Chien-Cheng , Lin Ran-Jin , Lin Hong-Ping , Chen Li-Chyong , Chen Kuei-Hsien
Published: April 2011

The Cu-based film catalysts with various additive metals have been successfully prepared by the electroless plating on ZnO nanorods/stainless steel substrates. The microstructure features of the Cu-based films are highly porous and composed of plate-type grains. The addition of zirconium, aluminum, and iron into Cu-based film catalyst can improve the activity and the stability of the film catalysts. The catalytic durability of the Cu-based film catalysts has also been improved by addition of Zr, Al, and Fe into Cu-based films. This is attributed to the formation of the stable ZrO2, Al2O3, and Fe2O3 nanoparticles with good dispersion in the films.
Group IV Nanocrystals for Silicon Photovoltaics
Authors: Liu X. , Saini S. , Vanhoutte M. , Bakalis J. , Yau W. , Eshed A. , Kimerling L.C. , Pervez N. , Kymissis I. , Wong C.W.
Published: April 2011

Silicon nanocrystals (nc-Si), have been shown to act as opto-electronic centers enabling light emission by carrier recombination, when precipitated in a silicon nitride (Si3N4) host. In this work, nc-Si and Germanium nanocrystals (nc-Ge) are studied in sputtered films of Si3N4 and SiGeN for application as tandem cell layers in a Si solar cell. The samples are annealed in a nitrogen gas and forming gas ambient, from 500 ºC to 900 ºC, to investigate the influence of temperature on photoluminescence and photoconductivity.
The Implications of Fossil Fuel Combustion for Climate Change
Authors: Ross Kristy Eileen , Piketh Stuart J.
Published: April 2011

Emissions from fossil fuel combustion alter the composition of the atmosphere and have been touted as a major cause of climate change. The amount of carbon dioxide in the atmosphere, for example, has increased by more than 30% since pre-industrial times. Average global surface temperature has increased by approximately 0.6 ± 0.2°C since the late 19th Century, and surface temperature records indicate that the 1990s are likely to have been the warmest decade of the last millennium. The anthropogenically-induced warming is superimposed on natural climatic variability. Proxy records show a regular oscillation, on a roughly 100,000-year cycle, between glacials and interglacials. Superimposed on these long-term oscillations are shorter scale variations. It is thought that changes in the seasonality and location of radiation from the Sun trigger the onset or end of glaciation, and the change is then amplified by feedbacks in the earth-atmosphere system. A firm link between atmospheric composition and temperature has been established from ice core records spanning the last 420,000 years, which show that changes in time of global temperature and atmospheric concentrations of carbon dioxide and methane are tightly coupled. Global average surface temperature is projected to increase by between 1.4 and 5.8°C by 2100, with the warming being greatest over land and polar regions. Precipitation is predicted to increase in the tropical, mid- and high-latitude regions, but to decrease in the subtropical regions. Alternative energy technologies such as hydrogen fuel cell vehicles will lower greenhouse gas emissions and reduce climate problems and costs.
Ion Irradiation Effects of Yttria-stabilized Zirconia Conductivity
Authors: Cheng Jeremy , Crabb Kevin , Pornprasertsuk Rojana , Huang Hong , Saito Yuji , Prinz Fritz B
Published: April 2011

The performance of solid oxide fuel cells is limited largely by ion transport in the electrolyte. Thin film electrolytes of yttria-stabilized zirconia were deposited by pulsed laser deposition. The electrolyte material was subjected to heavy ion irradiation and heat treatment and the effects on conductivity were measured using electrical impedance spectroscopy. Following irradiation there is a drop in conductivity by a factor of 3-4. After heat treatment at 800°C, the conductivity recovers to the as-deposited value.
Core-Shell Nanorods for Efficient Photoelectrochemical Hydrogen Production
Authors: Yu Z. G. , Pryor C. E. , Lau W. H. , Berding M. A. , MacQueen D. B.
Published: April 2011

We propose core-shell InP-CdS and InP-ZnTe nanorods as photoelectrodes in the efficient photoelectrochemical hydrogen production. Based on our systematic study using strain-dependent k.p theory, we find that in these heterostructures both energies and wave-function distributions of electrons and holes can be favorably tailored to a considerable extent by exploiting the interplay between quantum confinement and strain. Consequently, these core-shell nanorods with proper dimensions (height, core radius, and shell thickness) can simultaneously satisfy all criteria for effective photoelectrodes in solar-based hydrogen production.
Large Area Depositions of Si/SiC Quantum Well Films for Thermoelectric Generator Applications
Authors: Yu Tianhua , Efstathiadis Harry , Matyi Richard , Haldar Pradeep , Ghamaty Saeid , Elsner Norbert
Published: April 2011

Recent development in thermoelectric conversion, especially in the area of quantum well (QW) thin film materials, have demonstrated the potential to achieve the high efficiency and power density to fabricate future power supplies. In this study, we develop the large area QW films of N-type Si/SiC integrated with P-type B4C/B9C, which can be used as thermoelectric devices for waste heat recovery. The approach is to fabricate thick large area film stacks (up to 11 μm) deposited by sputter deposition technique on 6” n-type (100) silicon substrates, which might be proven to be a suitable method for potentially manufacturing large area thermoelectric devices in a cost effective manner. These more basic studies are being carried out to better understand variables such as film thickness, deposition rate and other important parameters of these ∼10 nm films. The resulting as deposited and annealed multilayer stacks were characterized in terms of thin film uniformity, thickness, growth rate, composition, and thermoelectric performance, by Spectroreflectometry, atomic force microscopy (AFM), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), X-ray reflectivity (XRR), and electrical measurements. Issues, which could cause film stack degradation, such as interface layer formation, film delamination, and crack formation lowering the device performance will be presented and correlated to device efficiency.