bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Synthesis Techniques for Yttrium Based Phosphors
Authors: Koparkar K.A. , Bajaj N.S. , Omanwar S.K.
Published: January 2015

In recent years, the term ‘smart materials’ which means the potential of a material having novel functional abilities, has become a buzz word. Luminescent materials held a lion’s share amongst all functional materials. The research in these materials is nowadays becoming the frontline platform and has challenging options for the betterment of society. These materials have applications in diverse fields such as, radiation detection, monitoring and assessment, display devices (PDP, CRT, CTV, LCD, FPD, etc.), and Lighting devices (CFL, Hg Free lamps using VUV Xenon, Solid State lighting (SSL-LED blue chips, UV-LEDs, O-LEDs, etc.). The main and essential role is being played by the phosphors. The activity of the phosphor is also depending on the particle size and hence the nanophase phosphor developments are very important aspect of development of functional materials. It is also very much clear now that the method of synthesis controls/decides a particle size of the final product. A particular method is better for a specific phosphor for getting the desired particle size of the final product. Scaling is also very much essential for instituting the specific method of synthesis for desired phosphor. These aspects are important for commercial production.Looking at the applications specified in first paragraph, one thing is common which is red correction required for display devices or lighting devices. The red correction in full-colour display/white light emission is essentially done by using Y2O3:Eu3+phosphor or Eu3+doped yttrium based hosts. Red emission is of Eu3+(5D0→7Fj, where j could be predominantly 2, 1, 3) when symmetrically organized environment. In this context, the review of yttrium based phosphors is being presented. This also covers our experience in synthesis of yttrium based luminescent materials with different methods of synthesis and their comparative aspects with regard to luminescence properties.Contents of Paper
Corrosion Behavior of Hybrid Sol-Gel Films Reinforced with Electrospun Nanofibers
Authors: Covelo Alba , Genescá Juan , Barba Arturo , Menchaca Carmina , Uruchurtu Jorge , Hernández Miguel
Published: January 2015

The aim of this paper is to evaluate the efficiency of hybrid sol-gel coatings reinforced with electrospinning nanofibers doped with cerium nitrate and ceria particles to increase the corrosion properties of the coating. Poly(vinyl alcohol) solutions doped with cerium nitrate and ceria were electrospun onto clean commercial aluminum alloy AA2024-T3 plates and then coated with a hybrid sol-gel system using the dip-coating procedure. The hybrid materials synthesized via sol-gel chemistry were prepared from inorganic-organic precursors: zirconium (IV) propoxide and 3-glycidoxypropyltrimetoxysilane. The electrochemical impedance spectroscopy technique was applied to evaluate the electrochemical properties of the film whereas scanning electron microscopy and atomic force microscopy were employed to characterize the surface characteristics. The incorporation of nanofibers into the sol-gel system provides good barrier properties that increase the corrosion resistance of the aluminum at longer exposure times in saline media. This protection depends of the type of inhibitor loaded within the electrospun nanofibers.
Galvanic Formation of Zn-Ni/Zn-Co Type Multilayer Alloy Coatings on Steel Substrate
Authors: Nagrabia Agnieszka , Sowa Maciej , Simka Wojciech , Maciej Artur
Published: January 2015

Zn-Ni and Zn-Co monolayer and Zn-Ni/Zn-Co multilayer (from 2 to 128 layers) alloy coatings were formed on steel substrate by electrodeposition from acidic Zn-Ni bath and neutral Zn-Co bath. Samples were tested in salt chamber for corrosion resistance in neutral salt spray. Open circuit potential measurement and gravimetric study of corrosion were carried for samples immersed in the 5% NaCl solution.It was found that coatings of Zn-Ni surface layer occurred higher corrosion resistance then the coatings of Zn-Co surface layer. Sixteen-layer coating with Zn-Ni surface layer proved to be most effective in protecting the steel substrate. Zn-Ni monolayer showed the lowest corrosion potential, which affects the corrosion properties. Sample weight changes during exposure to a corrosive environment are related to digestion of the coating and the formation of corrosion products.
Corrosion Resistance of Copper Sheet after Laser Treatment
Authors: Onyszczuk Tomasz , Zwolińska Marta , Mazurkiewicz Marta , Marczak Jan , Sarzyński Antoni , Garbacz Halina
Published: January 2015

This study concerns laser cleaning technology and its impact on copper corrosion resistances. The results of the treatment process were analyzed after irradiation at various laser powers and scanning velocities of the laser beam. The corrosion resistance of copper sheets, before and after laser irradiation, was examined in an NaCl solution at room temperature. Investigations included surface topography observations using a scanning electron microscope (SEM) together with chemical and phase composition determined by energy dispersive X-ray spectrometry (EDS) and Raman spectroscopy.
Mild Steel Passivation and Depassivation in Simulated Concrete Pore Solution Containing Bacteria Metabolites
Authors: Volpi Enrico , Stefanoni Matteo , Olietti Andrea , Trasatti Stefano
Published: January 2015

Although much less investigated than that induced by chlorides, the corrosion of steel reinforcing bars due to bacteria metabolic products is recognised as a serious issue, primarily for concrete pipes in sewer network. In order to overcome the complications due to the preparation of concrete samples the investigation was performed using simulating solutions. The passivation of the metallic specimens was obtained by immersion in Ca (OH)2 sat and monitored through several different electrochemical techniques. The depassivation was induced by either sulphuric acid or sulphides in order to simulate different bacterial metabolites. Anodic polarization curves and optical microscopy examination revealed a significant corrosion in the former case, while a competitive interaction among the sulphide and the alkalinity was hypothesized in sulphide-containing solutions.
Properties of Rubber Lining after Sixteen Years Operation in Different Places of FGD Plant
Authors: Drela Izydor , Masalski Jan , Łukaczyńska Monika , Szczygieł Bogdan
Published: January 2015

After over 16 years long service on the inner walls of a steel absorber and outlet channel in wet FGD system, the rubber lining was subjected to examinations. A series of impedance spectra for the pre-vulcanized soft rubber lining based on chlorobutyl rubber (CIIR) were recorded. Rubber lining samples taken from the absorber bottom, which had been in contact with the washer sump solution, exhibited properties similar to those of new rubber lining samples not exposed to the corrosive environment. Rubber lining samples taken from the absorber upper part and from the outlet channel showed significant damage, and so deterioration in their protective properties, in comparison with the new lining. Also the results of tensile strength and hardness tests carried out on rubber samples taken from various parts of the absorber and the outlet channel are presented.
Nanocomposite Layers Obtained by Electro-Co-Deposition: Corrosion and Tribocorrosion Properties
Authors: Benea Lidia
Published: January 2015

High dispersed nano and micro particles as ceramics (SiC, TiC, WC, Al2O3), polymers (UHMWPE) or bioceramics (TiO2, CeO2, ZrO2) have been deposited by electrochemical method with nichel or cobalt on metallic substrate to obtain novel structured composites, cermet or hybrid coatings with specific properties to be used in industrial or biomedical applications. The industrial applications for metal matrix based nanocomposites are increasing and open a way to biocompatible coatings. electrodeposition is considered to be one of the most important techniques for producing nanocomposites and nanostructured surfaces. Electrodeposition is exceptionally versatile, so that new and exciting applications are still being invented. The paper presents some results regarding the electro-co-deposition of dispersed phases as ZrO2, CeO2, SiC, WC, TiC or polymeric dispersed phases as UHMWPE (ultra high molecular weight polyethylene) during cobalt or nickel electroplating process in view of obtaining new advanced functional surfaces with improved properties to corrosion or tribocorrosion systems.
Hydrogenation and Corrosion Properties of LaNi4.5Co0.5-Based Alloy Doped with 1.7 at% Sn
Authors: Dymek Martyna , Bala Henryk , Drulis Henryk , Hackemer Alicja
Published: January 2015

Effect of small addition of tin (1.7 at.%) into LaNi4.5Co0.5 alloy on gas phase and cathodically charged hydrogen absorption ability as well as its corrosion resistance in 6M KOH solution is discussed. To reveal the effect of Sn doping three alloys have been selected: LaNi4.5Co0.5 (precursor), LaNi4.5Co0.5Sn0.1 and LaNi5 - as a parent compound. The room temperature p-C isotherms indicate to beneficial effect of Sn addition which causes decrease of H2 equilibrium pressure and does not limit atomic hydrogen solubility. Discharge capacities (Qdisch), exchange current densities of H2O/H2 system () as well as corrosion rates () have been determined for the tested alloys on the basis of cyclic galvanostatic measurements (at –0.5C/+0.5C rates). It has been shown that for N > 3 cycle the discharge capacity of LaNi4.5Co0.5 is ca twofold greater than that for LaNi5 reference. Addition of 1.7 at.% Sn into Co-containing alloy expands the discharge capacity by 30-40%. The Co containing alloys reveal twice as great exchange current densities of H2O/H2 system compared to LaNi5, however, Sn addition slightly decreases the , especially for latest cycles. The partial cobalt substitution for Ni accelerates alloy corrosion in alkaline solution, however, tin addition fully eliminates this effect.
Hydrogen Absorption by Co-Substituted Nd-Fe-B High Coercivity Magnetic Material
Authors: Bala Henryk , Dymek Martyna , Szymura Stefan , Rabinovich Yuri M.
Published: January 2015

The present paper aims at explanation of the advantageous role of partial substitution of iron by cobalt in Nd-Fe-B magnet for distinct inhibition of mechanically assisted corrosion phenomena. The hydrogen uptake by Nd16Fe76B8 and Nd16Fe56Co20B8 sintered materials have been compared with the use of charge/discharge method in terms of the alloys corrosion behavior in strong alkaline solution. For initial cycles, the hydrogen discharge capacity of Co-containing alloy is 5-10 times lower than that for the Nd16Fe76B8 reference alloy. After 6-7 cycles both alloys reveal comparable hydrogen capacity. Also the plots of polarization curves testify to comparable corrosion resistance for both materials. The unusual resistance of Nd16Fe56Co20B8 sinter to pulverization should be ascribed to strong inhibition of hydrogen absorption at initial steps of corrosion process.
Influence of Ageing on the Corrosion Resistance of the ZnAl22Cu3 and ZnAl40Cu3 Alloys
Authors: Michalik Rafał
Published: January 2015

Subject of examinations were ZnAl22Cu3 and ZnAl40Cu3 alloys. The samples after solutionizing 3850C/10h and ageing 1750C/10h and for comparative purposes, in the initial state (just after casting) have been studied. Corrosion tests were carried out in “acid rain” solution. The scope of the examinations included potentiodynamic and potentiostatic tests , examination of the surface and structure of the samples after corrosion. The research found that corrosion of ZnAl22Cu3 and ZnAl40Cu3 alloys in the "acid rain" environment leads to a depletion of zinc in the upper surface layer and its enrichment in aluminium and copper resulting in decreasing the corrosion rate. Depending on the parameters (temperature, time) solutioning and ageing of ZnAl22Cu3 and ZnAl40Cu3 alloys can lead to an increase or decrease of the corrosion resistance in the "acid rain" environment.
The Effect of the Aluminide Coating on the Thermal Properties and Oxidation Resistance of Inconel 625 Ni-Base Superalloy
Authors: Zagula-Yavorska Maryana , Sieniawski Jan , Filip Ryszard , Drajewicz Marcin
Published: January 2015

An investigation was conducted to synthesize βNiAl coating on the nickel based superalloy Inconel 625 in the low activity chemical vapor deposition process (CVD). The deposition was carried out for 8 hours at 1050°C using the BPXpro3252 IonBond company equipment. Surface morphology and cross-section microstructure of the diffusion coating were studied and compared using an optical microscope, an X-ray diffractometer and a scanning electron microscope (SEM) equipped with an energy dispersive spectroscope. It was found that 29 μm thick aluminide coating consisted of two layers: an outer one and the inner interdiffusion one. The outer layer consisted of the βNiAl phase. The inner one consisted of the βNiAl phase with chromium, molybdenum and niobium carbides (M23C6 and MC type) inclusions. Outer layer hardness was about 564 HV0.002 while interdiffusion layer hardness was about 725 HV0.002. Thermal diffusivity of Inconel 625 superalloy with and without coating was measured using a NETZSCH model 427 laser flash diffusivity apparatus. The thermal diffusivity measurements were conducted in the argon atmosphere at the temperature interval 20 - 1200 oC. Thermal diffusivity of the uncoated Inconel 625 Ni-base superalloy at the room temperature is about 2 mm2/s, while for the coated superalloy thermal diffusivity is about 2.8 mm2/s. The increase of the temperature from 20 to 1200 oC leads to the increase of the thermal diffusivity of the coated sample from 2.8 to 5.6 mm2/s. Cyclic oxidation tests for both coated and uncoated superalloys were performed at 1100°C for 1000 h in the air atmosphere. The aluminized samples exhibited a small mass increase and the α-Al2O3 scale was formed during the oxidation test.
The Impact of the Organic Form of Sulphur Originating from Coal on the Performance of Solid Oxide Fuel Cells
Authors: Dudek Magdalena
Published: January 2015

De-ashed coal samples involving from 0 to 0.6 %wt organic sulphur were investigated as solid fuels in a direct carbon solid oxide fuel cell (DC-SOFC). Prior to electrochemical investigations, the corrosion resistance of cell components in the coal bed was investigated at 900°C for 500h. X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of sulphur on the surface of the yttria fully-stabilised zirconia (8 %mol Y2O3 in ZrO2, 8YSZ) as well as the surface of the Ni-8YSZ cermet anode following these tests. The electrochemical oxidation of coal on the surface of 8YSZ as well as that of the Ni-8YSZ cermet anode was investigated at a temperature range of 580–850°C. It was found that the presence of the organic form of sulphur as an impurity of coal caused a more rapid decrease in current during operation of a DC-SOFC with an 8YSZ electrolyte under load. The unfavourable impact of this form of sulphur on the electrochemical oxidation of coal on the Ni-8YSZ surface is more complicated than in the case of the 8YSZ electrolyte. In the DC-SOFC with Ni-8YSZ anode material, the presence of organic form of sulphur in de-ashed coal leads to depreciation of the Ni-8YSZ anode material.
The Oxidation Resistance of Nonmodified and Zr-Modified Aluminide Coatings Deposited by the CVD Method
Authors: Filip Ryszard , Zagula-Yavorska Maryana , Pytel Maciej , Romanowska Jolanta , Maliniak Mateusz , Sieniawski Jan
Published: January 2015

The aim of the present work was to determine the influence of chemical composition of the protective coating on the oxidation resistance of the protected alloy. Zirconium modified and nonmodified aluminide coatings were deposited on the MAR M200 nickel superalloy by the CVD method. The oxidation tests were conducted at 1100°C into 23 hour in the air. The chemical composition (EDS) analysis was performed. The kinetic of oxidation of zirconium modified and nonmodified aluminide coatings was similar. Oxides inclusions called pegs were observed on the surface of oxidized aluminide coating. HfO2 oxide is more stable than Al2O3 oxide, hafnium atoms can replace aluminum atoms in Al2O3 oxides. This phenomena let to stabilize NiAl phase and increase of oxidation resistance of aluminide coating.
Evaluation of High-Temperature Corrosion on 16Mo3 Steel Long-Term Operated at an Elevated Temperature
Authors: Gwoździk Monika
Published: January 2015

The paper contains results of studies on the formation of oxide layers on steel long-term operated at an elevated temperature. The oxide layer was studied on a surface and a cross-section at the inner surface of the tube wall. Thorough examinations of the oxide layer carried out on the inside surface of tube wall comprised:microscopic examinations of the oxide layer were performed using an Olympus GX41 optical microscope,thickness measurements of formed oxide layers,chemical composition analysis of deposits/oxides using a Joel JSM-6610LV scanning electron microscope (SEM) working with an Oxford EDS electron microprobe X-ray analyser,X-ray (XRD) measurements; the layer was subject to measurements using a Seifert 3003T/T X-ray diffractometer and the radiation originating from a tube with a cobalt anode (λCo=0.17902 nm). X-ray studies were performed, comprising measurements in a symmetric Bragg-Brentano geometry (XRD). XRD measurements were performed in the 15÷120° range of angles with an angular step of 0.1° and the exposure time of 4 s. To interpret the results the diffractograms were described by a Pseudo Voight curve using the Analyze software. DHN PDS and PDF4+2009 computer software and crystallographic database were used for the phase identification.
Process Temperature Effect on Surface Layer of Vacuum Carburized Low-Alloy Steel Gears
Authors: Dychtoń Kamil , Rokicki Paweł , Nowotnik Andrzej , Drajewicz Marcin , Sieniawski Jan
Published: January 2015

Gears, due to their complex shape, carried load and required accuracy are ones of most complex aircraft engine parts. Single tooth damage usually breaks the power transmission and causes failure of the entire gear system. Adequate sustainability and guarantees of transmission is therefore a condition for secure operation of whole device. Particularly high requirements for reliability are put to transmissions used in the aerospace industry. Due to the loads which are transmitted through the gears, the materials used by the manufacturer must have not only high strength but also show the abrasion resistance of the surface layer and the ductility of the core. Thermo-chemical treatment of industrial gears is a fundamental process, which gives them adequate mechanical properties regarding loads they carry and the surface conditions of work. The most promising method in the discussed field is vacuum carburizing, which by its specification of work significantly reduce the emission of CO2 and the duration of the process, without reducing the quality of the final product. The main aim of the paper is to present criteria for selection of carburizing parameters (mainly temperature increase) as a part of thermo-chemical treatment process performed using vacuum methods. Proper (higher to compare with conventional methods) carburizing process temperature is crucial in programming of carbon diffusion process meaning in process time and final carburized layer characteristics as carbon profile and homogeneity of the carburized layer.
Corrosion Resistance of Ti6Al7Nb Alloy after Various Surface Modifications
Authors: Szewczenko Janusz , Basiaga Marcin , Kiel-Jamrozik Marta , Kaczmarek Marcin , Grygiel Magdalena
Published: January 2015

The influence of surface pretreatment prior to the anode oxidation of Ti6Al7Nb alloy samples on corrosion resistance was presented in the work. The preliminary surface treatments were: grinding, vibration machining, sandblasting and electrochemical polishing. Anodic oxidation process was carried out at different voltages. The final procedure of the surface modification was steam sterilization. The scope of the work included: corrosion resistance study (pitting and crevice) of both non-sterilized and sterilized samples, and samples after 28 days exposure to the Ringer’s solution, concentration evaluation of metal ions releasing from the sterilized surface as well as observations of surface topography. The research revealed a significant influence of surface pretreatment of Ti6Al7Nb alloy, prior to the anode oxidation and steam sterilization, on corrosion resistance.
Electrochemical Properties of cpTi with Modified Surface Used for Implants in Blood and Vascular System
Authors: Walke Witold , Paszenda Zbigniew , Basiaga Marcin , Karasiński Paweł , Kaczmarek Marcin
Published: January 2015

In their works the authors presented results of tests conducted for titanium Grade4 after its surface modification with the application of anodic oxidation and sol-gel (SiO2 layer) methods. In order to verify the usefulness of the obtained surface layers potentiodynamic and impedance tests have been carried out. They have been conducted with the use of measurement set equipped with the POSTAT 302n potentiostat with the FRA2 attachment for impedance tests. Measurements have been taken in an environment simulating human blood – artificial serum having temperature of T = 37 degrees Centigrade. To identify phenomenon occurring at phases border samples have been subjected to 28-day exposition in the artificial serum. It has been found that in the case of anodic oxidation the value of voltage of 100 V has an advantageous influence on electrochemical properties of modified surfaces. On the other hand, in the case of the sol-gel method thin layer of SiO2 baked at temperature T = 430 degrees Centigrade has been characterised by the most advantageous set of electrochemical properties. The knowledge of proper parameters of creating of surface layers has direct influence on the product quality and thus, appropriate course of patient therapy process.
Corrosion Behaviour of Thermodiffusion Coatings on Titanium Implants in Simulated Body Fluids
Authors: Tkachuk Oleh , Proskurnyak Roman , Pohrelyuk Iryna , Fedirko Viktor
Published: January 2015

The influence of temperature change of isotonic 0.9 % NaCl solution and Ringer's solution from 36 оС to 40 оС on the corrosion resistance of Ti-6Al-4V alloy with nitride and oxynitride coatings was studied. It was shown that increase of the temperature of 0.9 % NaCl and Ringer's solutions doesn′t deteriorate the protective function of oxynitride coating on Ti-6Al-4V alloy. It was determined that by increasing the temperature of Ringer's solution the corrosion processes on nitride coating are accelerated, while in 0.9 % NaCl the nitride coating provides the stable characteristics.
Experimental Corrosion Tests on Weathering Steel Bridges
Authors: Krivy Vit , Kreislova Katerina , Urban Viktor
Published: January 2015

The paper introduces the experimental corrosion tests that are carried out on the existing weathering steel bridges in the Czech Republic. The influence of the position and location of the surface in the structure on the resulting corrosion rates can be evaluated using this experimental testing. Typical surfaces of steel bridges are tested, e.g. webs of main girders, upper and lower surfaces of flanges, surfaces affected by leaking salt solutions. The corrosion tests to study the relation between steel grade (weathering steels S355J2WP and S355J2W) and corrosion rates are introduced in this paper as well.
Corrosion Behavior of MRI153M Magnesium Alloy in 3% NaCl Solution
Authors: Gaon Ohad , Kazanski Barbara , Lugovskoy Alex
Published: January 2015

Corrosion behavior of high-pressure die cast creep resistant magnesium alloy MRI 153M in 3% NaCl aqueous solution was studied by several electrochemical and non-electrochemical techniques. The electrochemical techniques were Electrochemical Impedance Spectroscopy (EIS), Linear Polarization Resistance (LPR) and Tafel-slope Polarization. The non-electrochemical techniques were mass-loss and gas evolution measurements. Values of corrosion rates were calculated and the morphology of corroded surface studied. While corrosion rates calculated by both non-electrochemical methods are not consistent, those gained by the three electrochemical methods demonstrate consistency. In general, the rate of corrosion calculated by the gas evolution method is in a good agreement with the corrosion rate calculated from the electrochemical methods, which should be an indication of mixed chemical-electrochemical character of the process. SEM and light microscope observation of corroded specimens demonstrated the localized character of corrosion, at least at the initial stages.
Treatment results in advanced stage Hodgkin’s lymphoma
Authors: Jain H , Sengar M , Nair R , Menon H , Laskar S , Shet T , Gujral S , Sridhar E
Published: January 2015

Background:

Hodgkin's lymphoma displays distinct epidemiological attributes in Asian population thus making it relevant to study whether there are any differences in treatment outcomes too when treated with current standard of care.

Aim:

To evaluate the treatment outcomes of de-novo advanced stage HL in adults.

Materials and Methods:

This retrospective study included de-novo advanced stage HL patients (≥15 years) registered at our center from January 2004 to December 2007. Treatment outcomes were measured in terms of response rates, overall survival (OS) and progression-free survival (PFS). Overall and PFS were calculated with Kaplan-Meier methodology and Cox-proportional hazards model was used for multivariate analysis to identify prognostic factors.

Results:

There were 125 patients (males 77%) who received minimum one cycle of chemotherapy with median age of 32 years (Range 15-65 years). Stage IV disease was seen in (46 patients) 37%; 75% (94 patients) patients had B symptoms. International prognostic score (IPS) ≤4 was seen in 95/112 (85%) patients. ABVD (adriamycin, bleomycin, vinblastine, dacarbazine) chemotherapy was given to 94%. Radiation to residual/bulky sites was given to 36% (45 patients). Response data was available for 112 patients; complete response in 76%; partial response in 10 % and progressive disease in 3 patients. Nineteen deaths (progressive disease-7, toxicity-8, unrelated cause-4) were observed. At median follow-up of 28 months, estimated 5-year OS and PFS were 60% and 58%, respectively. On multivariate analysis, IPS and response to treatment were significant factors for both OS and PFS. Conclusions: The treatment outcomes in this study are comparable with the published literature with limited follow-up data.
Surgical checklist application and its impact on patient safety in pediatric surgery
Authors: Oak SN , Dave NM , Garasia MB , Parelkar SV
Published: January 2015

Background:

Surgical care is an essential component of health care of children worldwide. Incidences of congenital anomalies, trauma, cancers and acquired diseases continue to rise and along with that the impact of surgical intervention on public health system also increases. It then becomes essential that the surgical teams make the procedures safe and error proof. The World Health Organization (WHO) has instituted the surgical checklist as a global initiative to improve surgical safety.

Aims:

To assess the acceptance, application and adherence to the WHO Safe Surgery Checklist in Pediatric Surgery Practice at a university teaching hospital.

Materials and Methods:

In a prospective study, spanning 2 years, the checklist was implemented for all patients who underwent operative procedures under general anesthesia. The checklist identified three phases of an operation, each corresponding to a specific period in the normal flow of work: Before the induction of anesthesia ("sign in"), before the skin incision ("time out") and before the patient leaves the operating room ("sign out"). In each phase, an anesthesiologist,-"checklist coordinator," confirmed that the anesthesia, surgery and nursing teams have completed the listed tasks before proceeding with the operation and exit. The checklist was used for 3000 consecutive patients.

Results:

No major perioperative errors were noted. In 54 (1.8%) patients, children had the same names and identical surgical procedure posted on the same operation list. The patient identification tag was missing in four (0.1%) patients. Mention of the side of procedures was missing in 108 (3.6%) cases. In 0.1% (3) of patients there was mix up of the mention of side of operation in the case papers and consent forms. In 78 (2.6%) patients, the consent form was not signed by parents/guardians or the side of the procedure was not quoted. Antibiotic orders were missing in five (0.2%) patients. In 12 (0.4%) cases, immobilization of the patients was suboptimal, which led to displacement of diathermy grounding pad. In 54 (1.8%) patients, the checklist was not used at all. In 76 (2.5%) patients the checklist was found to be incompletely filled. Conclusions: Our study supports the use of the checklist as an essential safety tool and reinforcement of the same. The checklist may act as a valuable prompt to focus the team, to ensure that even the simple things have been cared for.
Energy Limits in Second Generation High-pitch Dual Source CT - Comparison in an Upper Abdominal Phantom
Authors: Beeres Martin , Bauer Ralf W , Kerl Josef M , Vogl Thomas J , Lee Clara
Published: January 2015

Objectives:

The aim of our study was to find out how much energy is applicable in second-generation dual source high-pitch computed tomography (CT) in imaging of the abdomen.

Materials and Methods:

We examined an upper abdominal phantom using a Somatom Definition Flash CT-Scanner (Siemens, Forchheim, Germany). The study protocol consisted of a scan-series at 100 kV and 120 kV. In each scan series we started with a pitch of 3.2 and reduced it in steps of 0.2, until a pitch of 1.6 was reached. The current was adjusted to the maximum the scanner could achieve. Energy values, image noise, image quality, and radiation exposure were evaluated.

Results:

For a pitch of 3.2 the maximum applicable current was 142 mAs at 120 kV and in 100 kV the maximum applicable current was 114 mAs. For conventional abdominal imaging, current levels of 200 to 260 mAs are generally used. To achieve similar current levels, we had to decrease the pitch to 1.8 at 100 kV — at this pitch we could perform our imaging at 204 mAs. At a pitch of 2.2 in 120 kV we could apply a current of 206 mAs.

Conclusion:

We conclude our study by stating that if there is a need for a higher current, we have to reduce the pitch. In a high-pitch dual source CT, we always have to remember where our main focus is, so we can adjust the pitch to the energy we need in the area of the body that has to be imaged, to find answers to the clinical question being raised.
Transcatheter Renal Interventions: A Review of Established and Emerging Procedures
Authors: Minocha Jeet , Parvinian Ahmad , Bui James T , Knuttinen Martha Grace , Ray Charles E , Gaba Ron C
Published: January 2015

Catheter-based interventions play an important role in the multidisciplinary management of renal pathology. The array of procedures available to interventional radiologists (IRs) includes established techniques such as angioplasty, stenting, embolization, thrombolysis, and thrombectomy for treatment of renovascular disease, as well as embolization of renal neoplasms and emerging therapies such as transcatheter renal artery sympathectomy for treatment of resistant hypertension. Here, we present an overview of these minimally invasive therapies, with an emphasis on interventional technique and clinical outcomes of the procedure.
Hypertrophic Olivary Degeneration – A Report of Two Cases
Authors: Sarawagi Radha , Murugesan Aravind
Published: January 2015

Hypertrophic olivary degeneration (HOD) is seen following lesions in the Guillain–Mollaret triangle. This is unique because the inferior olivary nucleus hypertrophies following degeneration unlike the typical atrophy seen in other structures. We report two cases of HOD in two different clinical scenarios.
Fatty Acid-Binding Protein 4 (FABP4): Pathophysiological Insights and Potent Clinical Biomarker of Metabolic and Cardiovascular Diseases
Authors: Furuhashi Masato , Saitoh Shigeyuki , Shimamoto Kazuaki , Miura Tetsuji
Published: February 2015

Over the past decade, evidences of an integration of metabolic and inflammatory pathways, referred to as metaflammation in several aspects of metabolic syndrome, have been accumulating. Fatty acid-binding protein 4 (FABP4), also known as adipocyte FABP (A-FABP) or aP2, is mainly expressed in adipocytes and macrophages and plays an important role in the development of insulin resistance and atherosclerosis in relation to metaflammation. Despite lack of a typical secretory signal peptide, FABP4 has been shown to be released from adipocytes in a non-classical pathway associated with lipolysis, possibly acting as an adipokine. Elevation of circulating FABP4 levels is associated with obesity, insulin resistance, diabetes mellitus, hypertension, cardiac dysfunction, atherosclerosis, and cardiovascular events. Furthermore, ectopic expression and function of FABP4 in several types of cells and tissues have been recently demonstrated. Here, we discuss both the significant role of FABP4 in pathophysiological insights and its usefulness as a biomarker of metabolic and cardiovascular diseases.
On noncommutative principal bundles with finite abelian structure group
Authors: Wagner Stefan
Published: February 2015

Let

\Lambda

be a finite abelian group. A dynamical system with transformation group

\Lambda

is a triple

(A,\Lambda,\alpha)

, consisting of a unital locally convex algebra

A

, the finite abelian group

\Lambda

and a group homomorphism

\alpha:\Lambda\rightarrow\operatorname{Aut}(A)

, which induces an action of

\Lambda

on

A

. In this paper we present a new, geometrically oriented approach to the noncommutative geometry of principal bundles with finite abelian structure group based on such dynamical systems.
$\mathcal{Z}$ is universal
Authors: Jacelon Bhishan , Winter Wilhelm
Published: February 2015

We use order zero maps to express the Jiang–Su algebra

\mathcal{Z}

as a universal C*-algebra on countably many generators and relations, and we show that a natural deformation of these relations yields the stably projectionless algebra

\mathcal{W}

studied by Kishimoto, Kumjian and others. Our presentation is entirely explicit and involves only *-polynomial and order relations.
Detailed source term estimation of the atmospheric release for the Fukushima Daiichi Nuclear Power Station accident by coupling simulations of an atmospheric dispersion model with an improved deposition scheme and oceanic dispersion model
Authors: Katata G. , Chino M. , Kobayashi T. , Terada H. , Ota M. , Nagai H. , Kajino M. , Draxler R. , Hort M. C. , Malo A. , Torii T. , Sanada Y.
Published: January 2015

Abstract. Temporal variations in the amount of radionuclides released into the atmosphere during the Fukushima Daiichi Nuclear Power Station (FNPS1) accident and their atmospheric and marine dispersion are essential to evaluate the environmental impacts and resultant radiological doses to the public. In this paper, we estimate the detailed atmospheric releases during the accident using a reverse estimation method which calculates the release rates of radionuclides by comparing measurements of air concentration of a radionuclide or its dose rate in the environment with the ones calculated by atmospheric and oceanic transport, dispersion and deposition models. The atmospheric and oceanic models used are WSPEEDI-II (Worldwide version of System for Prediction of Environmental Emergency Dose Information) and SEA-GEARN-FDM (Finite difference oceanic dispersion model), both developed by the authors. A sophisticated deposition scheme, which deals with dry and fog-water depositions, cloud condensation nuclei (CCN) activation, and subsequent wet scavenging due to mixed-phase cloud microphysics (in-cloud scavenging) for radioactive iodine gas (I2 and CH3I) and other particles (CsI, Cs, and Te), was incorporated into WSPEEDI-II to improve the surface deposition calculations. The results revealed that the major releases of radionuclides due to the FNPS1 accident occurred in the following periods during March 2011: the afternoon of 12 March due to the wet venting and hydrogen explosion at Unit 1, midnight of 14 March when the SRV (safety relief valve) was opened three times at Unit 2, the morning and night of 15 March, and the morning of 16 March. According to the simulation results, the highest radioactive contamination areas around FNPS1 were created from 15 to 16 March by complicated interactions among rainfall, plume movements, and the temporal variation of release rates. The simulation by WSPEEDI-II using the new source term reproduced the local and regional patterns of cumulative surface deposition of total 131I and 137Cs and air dose rate obtained by airborne surveys. The new source term was also tested using three atmospheric dispersion models (Modèle Lagrangien de Dispersion de Particules d'ordre zéro: MLDP0, Hybrid Single Particle Lagrangian Integrated Trajectory Model: HYSPLIT, and Met Office's Numerical Atmospheric-dispersion Modelling Environment: NAME) for regional and global calculations, and the calculated results showed good agreement with observed air concentration and surface deposition of 137Cs in eastern Japan.
Joint analysis of continental and regional background environments in the western Mediterranean: PM1 and PM10 concentrations and composition
Authors: Ripoll A. , Minguillón M. C. , Pey J. , Pérez N. , Querol X. , Alastuey A.
Published: January 2015

Abstract. The complete chemical composition of atmospheric particulate matter (PM1 and PM10) from a continental (Montsec, MSC, 1570 m a.s.l.) and a regional (Montseny, MSY, 720 m a.s.l) background site in the western Mediterranean Basin (WMB) were jointly studied for the first time over a relatively long-term period (January 2010–March 2013). Differences in average PMX concentration and composition between both sites were attributed to distance to anthropogenic sources, altitude, and different influence of atmospheric episodes. All these factors result in a continental-to-regional background increase of 4.0 μg m−3 for PM10 and 1.1 μg m−3 for PM1 in the WMB. This increase is mainly constituted by organic matter, sulfate, nitrate, and sea salt. However, higher mineral matter concentrations were measured at the continental background site owing to the higher influence of long-range transport of dust and dust resuspension. Seasonal variations of aerosol chemical components were attributed to evolution of the planetary boundary layer (PBL) height throughout the year, variations in the air mass origin, and differences in meteorology. During warmer months, weak pressure gradients and elevated insolation generate recirculation of air masses and enhance the development of the PBL, causing the aging of aerosols and incrementing pollutant concentrations over a large area in the WMB, including the continental background. This is reflected in a more similar relative composition and absolute concentrations of continental and regional background aerosols. Nevertheless, during colder months the thermal inversions and the lower vertical development of the PBL leave MSC in the free troposphere most of the time, whereas MSY is more influenced by regional pollutants accumulated under winter anticyclonic conditions. This results in much lower concentrations of PMX components at the continental background site with respect to those at the regional background site. The influence of certain atmospheric episodes caused different impacts at regional and continental scales. When long-range transport from central and eastern Europe and from north Africa occurs, the continental background site is frequently more influenced, thus indicating a preferential transport of pollutants at high altitude layers. Conversely, the regional background site was more influenced by regional processes. Continental and regional aerosol chemical composition from the WMB revealed (a) high relevance of African dust transport and regional dust resuspension; (b) low biomass burning contribution; (c) high organic matter contribution; (d) low summer nitrate concentrations; and (e) high aerosol homogenization in summer.
SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications
Authors: Snider G. , Weagle C. L. , Martin R. V. , van Donkelaar A. , Conrad K. , Cunningham D. , Gordon C. , Zwicker M. , Akoshile C. , Artaxo P. , Anh N. X. , Brook J. , Dong J. , Garland R. M. , Greenwald R. , Griffith D. , He K. , Holben B. N. , Kahn R. , Koren I. , Lagrosas N. , Lestari P. , Ma Z. , Vanderlei Martins J. , Quel E. J. , Rudich Y. , Salam A. , Tripathi S. N. , Yu C. , Zhang Q. , Zhang Y. , Brauer M. , Cohen A. , Gibson M. D. , Liu Y.
Published: January 2015

Abstract. Ground-based observations have insufficient spatial coverage to assess long-term human exposure to fine particulate matter (PM2.5) at the global scale. Satellite remote sensing offers a promising approach to provide information on both short- and long-term exposure to PM2.5 at local-to-global scales, but there are limitations and outstanding questions about the accuracy and precision with which ground-level aerosol mass concentrations can be inferred from satellite remote sensing alone. A key source of uncertainty is the global distribution of the relationship between annual average PM2.5 and discontinuous satellite observations of columnar aerosol optical depth (AOD). We have initiated a global network of ground-level monitoring stations designed to evaluate and enhance satellite remote sensing estimates for application in health-effects research and risk assessment. This Surface PARTiculate mAtter Network (SPARTAN) includes a global federation of ground-level monitors of hourly PM2.5 situated primarily in highly populated regions and collocated with existing ground-based sun photometers that measure AOD. The instruments, a three-wavelength nephelometer and impaction filter sampler for both PM2.5 and PM10, are highly autonomous. Hourly PM2.5 concentrations are inferred from the combination of weighed filters and nephelometer data. Data from existing networks were used to develop and evaluate network sampling characteristics. SPARTAN filters are analyzed for mass, black carbon, water-soluble ions, and metals. These measurements provide, in a variety of regions around the world, the key data required to evaluate and enhance satellite-based PM2.5 estimates used for assessing the health effects of aerosols. Mean PM2.5 concentrations across sites vary by more than 1 order of magnitude. Our initial measurements indicate that the ratio of AOD to ground-level PM2.5 is driven temporally and spatially by the vertical profile in aerosol scattering. Spatially this ratio is also strongly influenced by the mass scattering efficiency.
A method for stable carbon isotope ratio and concentration measurements of ambient aromatic hydrocarbons
Authors: Kornilova A. , Moukhtar S. , Saccon M. , Huang L. , Zhang W. , Rudolph J.
Published: January 2015

Abstract. A technique for compound specific analysis of stable carbon isotope ratios and concentration of ambient volatile organic compounds (VOC) is presented. It is based on selective VOC sampling onto adsorbent filled cartridges by passing large volumes of air (up to 80 L) through the cartridge. The hydrocarbons are recovered by thermal desorption followed by two step cryogenic trapping and then are separated by gas chromatography in the laboratory. Once separated, individual VOC are subjected to online oxidation in a combustion interface and isotope ratio analysis by isotope ratio mass spectrometry. The method allows measurements of stable carbon isotope ratios of ambient aromatic VOC present in low pptV to ppbV levels with an accuracy of typically better than 0.5‰. The precision of concentration measurements is better than 10%. Examples of measurements conducted as part of a joint Environment Canada-York University (EC-YU) measurement campaign at a semi-rural location demonstrate that the ability to make accurate measurements in air with low VOC mixing ratios is important to avoid bias from an over-representation of samples that are strongly impacted by recent emissions.
Statistical study of the night-time F-layer dynamics at the magnetic equator in West Africa during the solar minimum period 1995–1997
Authors: Tanoh K. S. , Adohi B. J.-P. , Coulibaly I. S. , Amory-Mazaudier C. , Kobea A. T. , Assamoi P.
Published: January 2015

Abstract. In this paper, we report on the night-time equatorial F-layer height behaviour at Korhogo (9.2° N, 5° W; 2.4° S dip lat), Ivory Coast, in the West African sector during the solar minimum period 1995–1997. The data were collected from quarter-hourly ionograms of an Ionospheric Prediction Service (IPS) 42-type vertical sounder. The main focus of this work was to study the seasonal changes in the F-layer height and to clarify the equinox transition process recently evidenced at Korhogo during 1995, the year of declining solar flux activity. The F-layer height was found to vary strongly with time, with up to three main phases. The night-to-night variability of these morphological phases was then analysed. The early post-sunset slow rise, commonly associated with rapid chemical recombination processes in the bottom part of the F layer, remained featureless and was observed regardless of the date. By contrast, the following event, either presented like the post-sunset height peak associated with the evening E × B drift, or was delayed to the midnight sector, thus involving another mechanism. The statistical analysis of the occurrence of these events throughout the solar minimum period 1995–1997 revealed two main F-layer height patterns, each characteristic of a specific season. The one with the post-sunset height peak was associated with the northern winter period, whereas the other, with the midnight height peak, characterized the northern summer period. The transition process from one pattern to the other took place during the equinox periods and was found to last only a few weeks. We discuss these results in the light of earlier works.