External Setup Research Articles

Direct Trace Element Analysis of Liquid Blood Samples by In-Air Ion Beam Analytical Techniques (PIXE-PIGE).

There are various liquid materials whose elemental composition is of interest in various fields of science and technology. In many cases, sample preparation or the extraction can be complicated, or it would destroy the original environment before the analysis (for example, in the case of biological samples). However, multielement direct analysis of liquid samples can be realized by an external PIXE-PIGE measurement system. Particle-induced X-ray and gamma-ray emission spectroscopy (PIXE, PIGE) techniques were applied in external (in-air) microbeam configuration for the trace and main element determination of liquid samples. The direct analysis of standard solutions of several metal salts and human blood samples (whole blood, blood serum, blood plasma, and formed elements) was realized. From the blood samples, Na, P, S, Cl, K, Ca, Fe, Cu, Zn, and Br elemental concentrations were determined. The focused and scanned ion beam creates an opportunity to analyze very small volume samples (∼10 μL). As the sample matrix consists of light elements, the analysis is possible at ppm level. Using this external beam setup, it was found that it is possible to determine elemental composition of small-volume liquid samples routinely, while the liquid samples do not require any preparation processes, and thus, they can be analyzed directly. In the case of lower concentrations, the method is also suitable for the analysis (down to even ∼1 ppm level) but with less accuracy and longer measurement times.

Chair-like pulses in an all-normal dispersion Ytterbium-doped mode-locked fiber laser.

We report, for what we believe is the first time, generation of stable chair-like pulses (a pulse shape with an initial long flat portion followed by a short high peak power portion resembling the shape of a chair) by mode locking of a Ytterbium (Yb)-doped fiber laser. Chair-like pulse shapes are achieved by implementing dual saturable absorbers, one based on a nonlinear optical loop mirror (NOLM) and the other based on nonlinear polarization rotation (NPR) inside the cavity. The transmission characteristics of the NOLM-NPR pair leading to the formation of chair-like pulses are numerically investigated. We also report the amplification characteristics of chair-like pulses in an external multistage Yb-doped fiber amplifier setup at different repetition rates of the pulse train. It was found that the chair-like pulses are suitable for amplification, and more than 10 W of average power at 460 kHz repetition rate have been obtained at total pump power of ∼20 W coupled to the power amplifier. At a lower repetition rate (115 kHz), ∼8 W of average power were obtained corresponding to ∼70 μJ of pulse energy with negligible contribution from amplified spontaneous emission or stimulated Raman scattering. We believe that such an oscillator-amplifier system could serve as an attractive tool for micromachining applications.

External beam IBA set-up with large-area thin Si3N4 window

A compact external beam setup has been constructed for Particle Induced X-ray Emission (PIXE) and Nuclear Reaction (NRA) analyses. The key issue in the design has been to obtain a wide beam spot size with maximized beam current utilizing a thin Si3N4 exit window. The employed specific exit window support enables use of foils with thickness of 100nm for a beam spot size of 4mm in diameter. The durable thin foil and the large beam spot size will be especially important for the complementary external beam NRA measurements. The path between the exit foil and sample is filled with flowing helium to minimize radiation hazard as well as energy loss and straggling, and to cool the samples. For sample-independent beam current monitoring and irradiation fluence measurement, indirect charge integration, based on secondary electron current measurement from a beam profilometer, is utilized.

Note: On-chip multifunctional fluorescent-magnetic Janus helical microswimmers.

Microswimmers integrated into microfluidic devices that are capable of self-illumination through fluorescence could revolutionize many aspects of technology, especially for biological applications. Few illumination and propulsion techniques of helical microswimmers inside microfluidic channels have been demonstrated. This paper presents the fabrication, detachment, and magnetic propulsions of multifunctional fluorescent-magnetic helical microswimmers integrated inside microfluidics. The fabrication process is based on two-photon laser lithography to pattern 3-D nanostructures from fluorescent photoresist coupled with conventional microfabrication techniques for magnetic thin film deposition by shadowing. After direct integration inside a microfluidic device, injected gas bubble allows gentle detachment of the integrated helical microswimmers whose magnetic propulsion can then be directly applied inside the microfluidic channel using external electromagnetic coil setup. With their small scale, fluorescence, excellent resistance to liquid/gas surface tension, and robust propulsion capability inside the microfluidic channel, the microswimmers can be used as high-resolution and large-range mobile micromanipulators inside microfluidic channels.

Trans-National Access in the field of heritage science at the Laboratory of Ion Beam Applications, MTA Atomki

The Laboratory of Ion Beam Applications at MTA Atomki served as a Trans-National Access (TNA) host within the CHARISMA EU FP7 project. Although cultural heritage research is only one of the several applications in the laboratory, its importance is growing thanks to the success of CHARISMA. The variety of samples and analytical questions in this field provides constant motivation for development of the instrumentation and adaptation of new techniques. We have special expertise in investigations with high lateral resolution and the PIXE analysis of lighter elements but we can also host projects when the in-vacuum measurements are not feasible, at our external micro-beam set-up. We continue the TNA activity within the IPERION CH project.

Development of a new in-air micro-PIXE set-up with in-vacuum charge measurements in Atomki

A new external microbeam set-up has recently been installed as the extension of the existing microprobe system at the Laboratory of Ion Beam Applications of Atomki, Debrecen, Hungary. The external beam set-up, based on the system of Oxford Microbeams (OM), is equipped with two X-ray detectors for PIXE analysis, a digital microscope, two alignment lasers and a precision XYZ stage for easy and reproducible positioning of the sample. Exit windows with different thicknesses and of different materials can be used according to the actual demands, currently silicon-nitride (Si3N4) film with 200nm thickness is employed in our laboratory. The first application was demonstrated in the field of archaeometry, on Bronze Age hoards from Hungary.

Programs for visualization, handling and quantification of PIXE maps at the AGLAE facility

The external beam setup of the AGLAE facility has been developed in order to combine PIXE with PIGE, EBS and recently IBIL for the analysis of cultural heritage artefacts. The upgraded external beam end-station integrates five large solid angle X-ray detectors either to reduce the risk of damage on sensitive artworks by decreasing the beam intensity or to routinely acquire elemental maps at various scales. While many programs are available to process PIXE maps acquired with nuclear microprobes, a software to process the major and trace elements PIXE maps point by point using GUPIX is not available. The present paper describes three programs developed for the AGLAE facility to process numerous maps obtained with multiple detectors. AGLAEMAP allows to handle maps and pixel groups within maps, TRAUPIXE to process quantitatively PIXE spectra of all pixels and DATAIMAGING to display the resulting quantitative elemental maps. The benefits of this software suite are demonstrated by processing a dataset acquired on a pellet of geostandard reference material and on a terre mêlée pottery shard sample created by the famous ceramist Bernard Palissy (1510–1589), highlighting chemical elements present in this polychrome ceramic.

Feasibility study of patient motion monitoring by using tactile array sensors

An ideal alignment method based on the external anatomical surface of the patient should consider the entire region of interest. However, optical-camera-based systems cannot blindly monitor such areas as the patient’s back, for example. Furthermore, collecting enough information to correct the associated deformation error is impossible. The study aim is to propose a new patient alignment method using tactile array sensors that can measure the distributed pressure profiles along the contact surface. The TactArray system includes one sensor, a signal-conditioning device (USB drive/interface electronics, power supply, and cables), and a PC. The tactile array sensor was placed between the patient’s back and the treatment couch, and the deformations at different location on the patient’s back were evaluated. Three healthy male volunteers were enrolled in this study, and pressure profile distributions (PPDs) were obtained with and without immobilization. After the initial pretreatment setup using the laser alignment system, the PPD of the patient’s back was acquired. The results were obtained at four different times and included a reference PPD dataset. The contact area and the center-of-pressure value were also acquired based on the PPD data for a more elaborate quantitative data analysis. To evaluate the clinical feasibility of using the proposed alignment method for reducing the deformation error, we implemented a real-time self-correction procedure. Despite the initial alignment, we confirmed that PPD variations existed in both cases of the volunteer studies (with and without the use of the immobilization tool). Additionally, we confirmed that the contact area and the center of pressure varied in both cases, and those variations were observed in all three volunteers. With the proposed alignment method and the real-time selfcorrection procedure, the deformation error was significantly reduced. The proposed alignment method can be used to account for the limitation of the camera-based system and to improve the accuracy of the external surface-based patient setup.

The complementarity of PIXE and PIGE techniques: A case study of size segregated airborne particulates collected from a Nigeria city

The Proton Induced X-ray Emission (PIXE) technique is a reliable ion beam analytical tool for the characterization of thin aerosol samples, but it can underestimate the lightest measurable elements (such as Na, Mg, Al and Si) owing to the absorption of their X-rays inside the sample. The Proton Induced Gamma-ray Emission (PIGE) technique could be employed as avalid means to determine corrections for such an effect. Hence, in this study, Fine (PM2.5) and Coarse (PM10–2.5) particulate matter samples collected at Ikeja, Lagos-Nigeria, using a double staged ‘Gent’ stacked sampler were analyzed for their elemental concentrations using an external beam set-up for simultaneous PIXE and PIGE measurements. The measured PIXE concentrations as well as the PIGE correction factors for Na and Al detected in the PM10–2.5 samples (collected on polycarbonate Nuclepore membranes) are reported. The concentrations of 24 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, Zr, Cs and Pb) detected in both fractions were displayed, discussed and likely sources of these elements were also identified.

Paintings on copper by the Flemish artist Frans Francken II: PIXE characterization by external microbeam

Resorting to an external proton microbeam, PIXE analyses of three oil paintings on copper support dated from the XVII century and attributed to the Flemish artist Frans Francken II, were undertaken. The present work aims to contribute to the compositional study of the painting materials employed by XVII century artists that exploited copper as a support for oil painting, and specifically the materials used by Francken’s workshop, particularly copper plates. Because of the low thickness of the pictorial layers of this type of paintings and its non-destructive character, PIXE is the ideal technique to study the elemental composition of the paintings. Several spots in each painting were chosen for analysis in order to cover almost all the pigments used in the colour palette. Lead and calcium were detected in practically every analysed regions, probably related to the presence of lead white and chalk, usually used as ground layer on copper paintings. Small quantities of gold were also detected, which is present in many of this artist’s works to embellish some details of the representations. Also this work reports the first application of the external proton microbeam set-up available at CTN/IST in Portugal for the characterization of oil paintings.

A Changeover Time Reduction through an integration of lean practices: a case study from pharmaceutical sector

Purpose – The purpose of this paper is to uncover the significance of quick changeovers in the packaging line of a pharmaceutical company. Using an integration of different lean practices, the study aims to reduce the batch change and changeover time up to 50 per cent, increasing overall equipment effectiveness by 25 per cent. Design/methodology/approach – The paper gives setup instructions and guidelines for preparing the standardized setup procedure without ignoring the actual constraints in a pharmaceutical company. It uses a case study to generate an integrated setup reduction approach, utilizing single-minute exchange of die tools (SMED) in combination with suppliers, inputs, process, outputs and customers (SIPOC), Kanban, 5S techniques and Total Productive Maintenance (TPM) indexes to achieve faster setups. Findings – The SMED approach helps the pharmaceutical company to eliminate unwanted activities and to externalize and reduce the internal activities by simplification or standardization. The application of other tools, such as 5S and Kanban tool-kits, allowed the company to optimize the process and reduce the standard deviation of the changeover times. Good manufacturing practice (GMP) procedures of the pharmaceutical sector limit the conversion of internal setup elements to external setup elements. Originality/value – The paper demonstrates the practical application of SMED, showing how it can bring real breakthroughs in productivity to a pharmaceutical company. Moreover, in this work, we highlight the importance of an integration of different lean practices to reduce variation in the changeover time. In particular, the standardization of setup tasks and the increased reliability in the material supply chain, in addition to reducing the changeover mean time can also reduce the standard deviation of the setup process time.

External-RBS, PIXE and NRA analysis for ancient swords

Elemental composition of the steel of two ancient swords (Japanese and Damascus from a private collection) was characterized using in air IBA techniques. Our results contribute for the understanding the processes of manufacturing (hammering and quenching) and surface treatments applied in these swords. The Particle Induced X-ray Emission (PIXE) measurements along the Damascus blade allowed to identify and to trace a superficial concentration profile for the elements such Cr, Mn, Fe, Ni, Cu, Zn and As, while results for the Japanese blade showed only the presence of iron. The carbon content on the surface was also investigated using a resonant region in the Elastic Backscattering Spectrometry (EBS) measurements and the results have shown a slightly difference between the surfaces under investigation. In order to investigate the nitrogen content on surface, that could explain the hardening process, we used Nuclear Reaction Analysis (NRA) and the results shown that nitrogen content was under our detection limit for the technique (0.3% in mass). The measurements of PIXE, NRA and EBS were taken using the external beam setup installed at Lamfi – São Paulo/Brazil, the latter being successfully implemented for the first time in this facility.

Elemental compositions of PM10–2.5 and PM2.5 aerosols of a Nigerian urban city using ion beam analytical techniques

The paucity of data on air quality studies in Nigeria prompted us to commence the sampling of particulate matter (PM10–2.5 and PM2.5) in Mushin Lagos, Nigeria. Both size-segregated fractions were collected using a double staged ‘Gent’ stack filter unit sampler. Elemental characterization was carried out by Particle Induced X-ray Emission (PIXE) and Proton Induced γ-ray Emission (PIGE) techniques using an external ion beam set-up. Twenty-four elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, Zr, Cs and Pb) were detected in both fractions and their concentrations were assessed. A study of their inter-elemental correlations indicated that some elements could have common source origins or similar chemical properties while enrichment factors (EF) displayed that most elements emanated from anthropogenic sources. Source apportionment studies are thus recommended.

Broad area diode laser with on-chip transverse Bragg grating stabilized in an off-axis external cavity.

The emission characteristics of a novel, specially designed broad area diode laser (BAL) with on-chip transversal Bragg resonance (TBR) grating in lateral direction were investigated in an off-axis external cavity setup. The internal TBR grating defines a low loss transversal mode at a specific angle of incidence and a certain wavelength. By providing feedback at this specific angle with an external mirror, it is possible to select this low loss transverse mode and stabilize the BAL. Near diffraction limited emission with an almost single lobed far field pattern could be realized, in contrast to the double lobed far field pattern of similar setups using standard BALs or phase-locked diode laser arrays. Furthermore, we could achieve a narrow bandwidth emission with a simplified setup without external frequency selective elements.

Heat-activated thermosensitive liposomal cisplatin (HTLC) results in effective growth delay of cervical carcinoma in mice

Cisplatin (CDDP) has been identified as the primary chemotherapeutic agent for the treatment of cervical cancer, but dose limiting toxicity is a key issue associated with its clinical application. A suite of liposome formulations of CDDP has been developed in efforts to reduce systemic toxicity, but their therapeutic advantage over the free drug has been modest due to insufficient drug release at the tumor site. This report describes the development of a novel heat-activated thermosensitive liposome formulation containing CDDP (HTLC) designed to release approximately 90% of the loaded drug in less than 5min under mild heating conditions (42°C). Physico-chemical characteristics of HTLC were assessed in terms of gel to liquid crystalline phase transition temperature (Tm), drug loading efficiency, particle size, and stability. The pharmacokinetic profile and biodistribution of HTLC in non-tumor-bearing mice were evaluated over a 24h period. A sophisticated spatio-temporal elucidation of HTLC release in tumor-bearing mice was achieved by way of real-time monitoring using a magnetic resonance (MR) imaging protocol, wherein a custom-built laser-based conformal heat source was applied at the tumor volume to trigger the release of HTLC co-encapsulated with the MR contrast agent gadoteridol (Gd-HP-DO3A). MR thermometry (MRT) demonstrated that a relatively uniform temperature distribution was achieved in the tumor volume using the external laser-based heating setup. In mice bearing subcutaneously-implanted ME-180 cervical tumors, the combination of HTLC and heat resulted in a 2-fold increase in tumor drug levels at 1h post-administration compared to HTLC without heating. Furthermore, the overall tumor accumulation levels for the HTLC groups (with and without heat) at 1h post-injection were significantly higher than the corresponding free CDDP group. This translated into a significant improvement in therapeutic efficacy evaluated as tumor growth delay (p<0.05) for the heated HTLC treatment group compared to the unheated HTLC, heated or unheated free CDDP, and saline groups. Overall, findings from this study demonstrate that a heat-activated, triggered release formulation of CDDP results in a significant enhancement in the therapeutic index of this drug.

The Effectiveness of the Single Minute Exchange of Die (SMED) Technique for the Productivity Improvement

The Single Minute Exchange of Die (SMED), a process-based innovation originally published in the mid-1980s, involves the separation and conversion of internal setup operations into external ones. Traditionally some of the manufacturing company facing the problem loss of available time due to spent time for the changeover processes. Changeover process time meaning changing the programming or operation sequences on the machine based on process requirement during the change from one to another one model especially for the mixing parts. SMED technique is a systematic approach that enables to reduce dramatically the set-up time or changeover time. Normally in the SMED technique, it was segregated between internal and external set-up. External set-up means any processing time was done up front which is before machine stop and internal time is any tasks was performed during machine in operating, which is considering changeover time. The impact to organization that it was increasing the productivity, capacity and at the same time increased the revenue. This paper focuses on the improving the productivity on the CNC machine process through implementing SMED technique and eliminating waste in the case study company.

A 24-channel implantable neural recording based on time and frequency-division multiplexing

This paper presents a novel approach to encapsulate prerecorded neural signals in implantable neural recording microsystems. We have increased the number of channels and the reconstructed neural signal quality in the receiver by combining time-division-multiplexing (TDM) and frequency-division-multiplexing (FDM) method. Reducing the number of channels in each TDM module is the fundamental advantage of this method that leads to reduced crosstalk noise. We evaluate some possible configurations and propose an optimized system that has less power dissipation and area occupation than other configurations. A 24-channel implantable neural recording based on the optimized system is designed in both system and circuit level. In this system, first, channels are divided into three 8-channel groups then after multiplexing in the time domain, they are combined together by FDM method. Finally, a frequency modulator wirelessly transmits neural signals to an external setup. In addition, we adjust local carrier frequencies and the bandwidth of TDM to synchronize detection without transmitting pilot carrier. To justify the system operation, using 0.18 μm CMOS technology, we design the system in circuit level. The designed circuit consumes a power of 1.39 mW at a supply voltage of 1.8 V. This leads to a power consumption of 58 μW per channel.

An Ant Colony Optimization Algorithm for the Press Shop Scheduling Problem

This paper deals with a real-life two machine scheduling problem for the side frame press shop in a truck manufacturing company. The shop consists of two machines where only the first machine, press machine, has separable, external and sequence dependent setup times. Moreover all the jobs require processing by the press machine more than once in their operation sequences with re-entrant work flows. Redefining the job elements, the problem is transformed into a general two machine flow shop problem which has a set of job-element precedence constraints. To solve the problem, an ant colony optimization (ACO) algorithm with the objective of the minimum makespan is developed. We investigate performance of the proposed ACO algorithm through the comparative study. Experiment results show that the proposed algorithm is more effective than existing method for the problem.

High peak power pulses from dispersion optimised modelocked semiconductor laser

Presented is an electrically pumped passively modelocked edge-emitting semiconductor laser system in an external cavity setup with intracavity dispersion management. This concept, in combination with a pulse compressor, provides pulses as short as 158 fs. By expanding the setup with a tapered diode laser amplifier, peak powers up to 6.5 kW were achieved in the 850 nm wavelength range.

External Setup in SMED Improvement in an Injection Molding Manufacturing Company

The purpose of the paper is to determine the applicability of external setup preparation activities of Single Minute Exchange of Die (SMED) in reducing setup time. Improving the external setup preparation of SMED leads a better and effective working performance. To improve the effectiveness of the external setup in SMED, it is concerned particularly with changing the internal activities into external activities and improving the current external activities. The process failure mode and effect analysis (PFMEA) adopted to analyze the problem faced of external set up process.The verification of the methods is done by an application a plastic injection molding manufacturing process where setup times are critical for time reduction.