bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability of cancer cell elasticity in force microscopy
Authors: Amiri Anahid , Hastert Florian D. , Heim Lars-Oliver , Dietz Christian
Published: February 2020

Evaluating the mechanical properties of biological cells in their living state is of upmost importance for understanding cellular behavior in health or disease and in particular cancer cells. In recent years, force microscopy and spectroscopy have become inevitable tools to attain the elastic modulus of cells as a whole using colloidal probes or with high lateral precision by sharp tips. However, the obtained values have to be treated with due care to avoid data misinterpretation. Here, we present a comparison of elasticity between four metastatic cancer cell lines (lung, liver, skin, and breast epithelial-type cancer cells) taken by colloidal and sharp probes using force spectroscopy on cell monolayers and stress the impact of a stiff substrate, which cells are attached to, on the measured values especially in cancerous cells, which depict abnormalities in structure and cellular components. As a result of our analysis, we suggest to solely use sharp probes for the mechanical characterization of cancer cells when the force-distance relation is fit by a conventional contact mechanics model such as the Hertz model.
Instanton theory of ground-state tunneling splittings with general paths
Authors: Eraković Mihael , Vaillant Christophe L. , Cvitaš Marko T.
Published: February 2020

We derive a multidimensional instanton theory for calculating ground-state tunneling splittings in Cartesian coordinates for general paths. It is an extension of the method by Mil’nikov and Nakamura [J. Chem. Phys. 115, 6881 (2001)] to include asymmetric paths that are necessary for calculating tunneling splitting patterns in multi-well systems, such as water clusters. The approach avoids multiple expensive matrix diagonalizations to converge the fluctuation prefactor in the ring-polymer instanton (RPI) method, and instead replaces them by an integration of a Riccati differential equation. When combined with the string method for locating instantons, we avoid the need to converge the calculation with respect to the imaginary time period of the semiclassical orbit, thereby reducing the number of convergence parameters of the optimized object to just one: the number of equally spaced system replicas used to represent the instanton path. The entirety of the numerical effort is thus concentrated in optimizing the shape of the path and evaluating hessians along the path, which is a dramatic improvement over RPI. In addition to the standard instanton approximations, we neglect the coupling of vibrational modes to external rotations. The method is tested on the model potential of malonaldehyde and on the water dimer and trimer, giving close agreement with RPI at a much-reduced cost.
Detectability and activity patterns of sambar deer (Rusa unicolor) in Baw Baw National Park, Victoria
Authors: Davies Christopher , Wright Wendy , Hogan Fiona E. , Davies Hugh
Published: February 2020

Introduced sambar deer (Rusa unicolor) are increasing in abundance and distribution across much of south-eastern Australia and causing damage to native ecosystems. However, the current paucity of knowledge surrounding many aspects of sambar deer ecology is limiting our capacity to make informed management decisions, and properly gauge the extent of deer impacts. Here we investigate correlates of sambar deer detectability and describe activity patterns of sambar deer in Baw Baw National Park (BBNP) to inform control operations. Camera traps were deployed in BBNP between October and December 2016. We used an occupancy modelling framework to investigate sambar deer detectability and camera trap record time stamps to determine sambar deer activity patterns. Sambar deer were found to be significantly more detectable near roads and in areas of sparse tree density and displayed strong crepuscular activity patterns. Control operations carried out along roads at dawn and dusk could be effective, at least in the short term. Likewise, aerial culling could be an effective control option for sambar deer populations in BBNP. This study highlights the utility of camera trap data to inform the application of control operations for cryptic invasive species.
Challenges and opportunities for grain farming on sandy soils of semi-arid south and south-eastern Australia
Authors: Unkovich Murray , McBeath Therese , Llewellyn Rick , Hall James , Gupta Vadakattu VSR , Macdonald Lynne M
Published: February 2020

Sandy soils make up a substantial fraction of cropping land in low rainfall (<450 mm p.a.) south and south-eastern Australia. In this paper we review the possible soil constraints to increased production on these soils in this region. Many of these soils have a very low (<3%) clay content and suffer from severe water repellency, making crop establishment and weed control problematic. Crops which do emerge are faced with uneven soil wetting and poor access to nutrients, with crop nutrition constraints exacerbated by low fertility (soil organic matter < 1%) and low cation exchange capacity. Zones of high penetration resistance appear common and have multiple causes (natural settling, cementation and traffic induced) which restrict root growth to <40 cm. Crop water use and grain yield are therefore likely to be well below the water-limited potential. Water repellency is readily diagnosed and where apparent should be the primary management target. Repellency can be mitigated through the use of furrow and other sowing technologies, along with soil wetting agents. These techniques appear to be affected by site and soil nuances and need to be refined for local soils and conditions. Once crop establishment on water repellent soils has been optimised, attention could be turned to opportunities for improving crop rooting depth through the use of deep tillage or deep ripping techniques. The required ripping depth, and how long the effects may last, are unclear and need further research, as do the most effective and efficient machinery requirements to achieve sustained deeper root growth. Crop nutrition matched to the water-limited crop yield potential is the third pillar of crop production that needs to be addressed. Low soil organic matter, low cation exchange capacity, low biological activity and limited nutrient cycling perhaps make this a greater challenge than in higher rainfall regions with finer textured soils. Interactions between nutrients in soils and fertilisers are likely to occur and make nutrient management more difficult. While amelioration (elimination) of water repellency is possible through the addition of clay to the soil surface, the opportunities for this may be restricted to the ~30% of the sandy soils of the region where clay is readily at hand. The amounts of clay required to eliminate repellency (~5%) are insufficient to significantly improve soil fertility or soil water holding capacity. More revolutionary soil amelioration treatments, involving additions and incorporation of clay and organic matter to soils offer the possibility of a more elevated crop yield plateau. Considerable research would be required to provide predictive capacity with respect to where and when these practices are effective.
Immigrants and Syrian refugees in the Turkish press
Authors: Doğanay Ülkü
Published: February 2020

This paper examines the way in which news reports and op-eds published in daily newspapers in Turkey handle the issues of asylum and refugees. The paper aims at revealing the patterns of discriminatory discourses towards refugees and also seeks an answer to the question of how much a discourse that will facilitate the acceptance of refugees and that will help them to be perceived as equipped with public rights finds a place in the Turkish press. The study examines the newspaper discourse on matters of immigration and asylum that is built within the news reports and op-eds of 7 national and 7 local newspapers from 1 June 2017 to 30 November 2018. The texts were first subjected to content analysis and then the selected news reports were treated based on the main components of the news discourse.
The omentum, a niche for premetastatic ovarian cancer
Authors: Ma Xiaojing
Published: February 2020

The work by Etzerodt et al. in this issue of JEM (https://doi.org/10.1084/jem.20191869) identifies a distinct omentum-resident macrophage population of embryonic origin and demonstrates that these cells provide a niche for ovarian cancer metastasis and cancer stemness. This research opens up for many questions and therapeutic prospects.
A variational approach to relativistic superfluid vortex elasticity
Authors: Andersson N , Wells S , Comer G L
Published: February 2020

It is well known that a superfluid rotates by forming an array of quantized vortices. A relativistic formulation for superfluid vortex dynamics is required for a range of problems in astrophysics and cosmology, from neutron star interiors and radio pulsar glitches to possible dark matter condensates on galactic scales. This paper develops a formalism for such systems, extending the well-established variational approach to relativistic fluids to account for the presence of a collection of quantized vortices. The model is firmly anchored in the geometry of the problem (drawing on aspects from basic string dynamics) and accounts for elastic aspects associated with a vortex array, providing a precise foundation for applications which have so far been based on somewhat ad hoc phenomenology.
Heterodyne interferometry at ultra-high frequencies with frequency-offset-locked semiconductor lasers
Authors: Kowarsch Robert , Rembe Christian
Published: February 2020

Modern broadband telecommunications require microelectromechanical filters which mechanically vibrate at ultra-high frequencies up to several gigahertz. Heterodyne interferometers, so-called laser-Doppler vibrometers (LDVs), provide a sensitive and contactless measurement technique for vibrations in such filters, but are limited in GHz heterodyning by the efficiency drop of acousto-optic frequency shifters. Heterodyning by frequency-offset locking of two lasers in an optoelectronic phase-locked loop (OPLL) overcomes this limitation. This is demonstrated with our LDV setup with heterodyning up to

1.4
 

G
H
z

via offset locking of two semiconductor lasers at visible wavelength. The experiments show a vibration-amplitude resolution of less than

1
 

p
m

per

H
z

for frequencies higher than

50
 

M
H
z

up to

700
 

M
H
z

. The bandwidth is only limited by our photodetectors. This amplitude resolution already qualifies our LDV for vibration measurement of microelectromechanical filters at ultra-high frequencies. We present a comprehensive model for the vibration-amplitude resolution of a LDV with this technique including the laser linewidths, the OPLL transfer function, and interferometer delays. The experiments with our LDV validate the model predictions from numerical simulations. Finally, we discuss the collapse of the heterodyne carrier at vanishing mutual coherence due to interferometer delays, the transition to shot-noise-limited detection, and provide design recommendations.
Spray drop measurements using depth from defocus
Authors: Zhou Wu , Tropea Cameron , Chen Benting , Zhang Yukun , Luo Xu , Cai Xiaoshu
Published: February 2020

Sprays are typically characterised by providing local drop size and velocity distributions and number density. The present work examines the possibility of obtaining such information using backlight photography, whereby two cameras are employed and the size and position of each imaged drop is obtained using a depth from defocus approach. A simple algorithm for estimating size and position from the two camera images is introduced and the sensitivity of this algorithm to various system parameters is investigated with simulations using synthetic images, measurements from a calibration facility, and measurements conducted in a sparse spray. Comparison measurements using the analysis of focused images are provided.
Validation of [99mTc]Tc-DTPA radiochemical testing method using one-system paper chromatography
Authors: Putra Amal Rezka , Lestary Enny , Maskur Maskur , Tahyan Yayan
Published: February 2020

Kidney failure is a degenerative disease that has a prevalence of nearly 12 to 15% of the total population in the world. Renal scans are one of many diagnostic means which refers to several examinations using radiopharmaceuticals that evaluate the function and anatomy of the kidneys. Technetium-99m-diethylenetriaminepetaacetic acid ([99Tc]Tc-DTPA) is a commonly used radiopharmaceutical for kidney scans. Since the half-life of technetium-99m radioisotope, one component of this radiopharmaceutical, is only about 6.0 hours, so an efficient and effective quality control techniques is a necessity. Up to now, two-systems thin layer chromatography (TLC) is a common method used for radiochemical purity (RCP) test of [99mTc]Tc-DTPA. Recently one-system TLC has been successfully developed for this purpose. Therefore prior to its application, it is necessary to validate as well to compare this method with an established method (WHO Pharmacopoeia). These methods were two-system used Whatman-1 paper as static phase and methyl ethyl ketone (two-system-A) and 0.9% sodium chloride (two-system-B) as mobile phases and one-system used Whatman-1 paper as static phase and acetone: 0.9% sodium chloride (11:9) as a mobile phase. RCP of [99mTc]Tc-DTPA was then tested using these methods. The retrieved data were processed and validated with some variables like accuracy, precision, and compared using t-test to see whether the above-mentioned TLC systems show a significant difference or not. The analysis results of RCP test of [99mTc]Tc-DTPA using two-system method was 99.37± 0.48% while using one-system method was 99.20 ± 0.41%. The percentage accuracy of the data between two methods was 99.83%. The t-stat value for both methods was 0.84 so it can be concluded that the results of measurement using one-system method are not significantly different from two-system method.
Quality assurance and quality control at dose calibrator to support nuclear medicine services
Authors: Nazaroh
Published: February 2020

One of the most important factors in health services is the quality and speed of service. However, the speed of service must be supported by the quality of service. Quality is often used as a benchmark and differentiator for a health service. Therefore, all producers and providers of health services must looking for ways to maintain and improve their quality. In this paper quality assurance (QA) and quality control (QC) will be presented at the dose calibrator (DC) to support nuclear medicine services. DC is a very useful tool for measuring radiopharmaceutical activity / dose (which will be given to patients) for diagnostic or therapeutic purposes. For accurate measurements, DC must be calibrated routinely, must pay attention to electronic factors, statistical considerations, ion recombination, background radiation, the source and volume container effects, source position, source adsorption, pure beta transmitter measurements and the presence of contaminants. One of the successes of patient care in nuclear medicine (NM) is by giving accurate doses, according to the type of cancer, the volume and severity of cancer cells. Accurate doses can be achieved by implementing QA and QC at DC, which starts from the calibration stage, checks stability, linearity, and pays attention to parameters that can affect measurement. The aim is to ensure that the measurement results meet the requirements and quality standards set. There are 5 parameters that can support QC implementation, namely PC3M: Person, Chain, Machine, Material and Method. If one of these 5 parameters is missing then QC cannot be implemented.
Characterization of porosity inside limestone as a reservoir of oil using neutron tomography
Authors: Bharoto B. , Ramadhani A. , Akbar F. , Sukaryo S. G. , Priyanto T. H. , Kurniati M. , Fadhila F. A.
Published: February 2020

As it is well known, limestone is a type of sedimentary rock that has a function as a reservoir of oil and gas. One of the factors that affect fluid saturation of the reservoir is the distribution of porosity inside the limestone that represents a percentage of the total available space for the oil and gas to fill in. Since hydrogen and carbon have strong attenuation to the thermal neutron, the oil-filled in the porosity can be investigated by the neutron tomography technique. Therefore, neutron tomography can be used to visualize the distribution of the porosity of the limestone. In this work, we report the characterization of the porosity inside the limestone obtained from the oil and petroleum gas institution of Indonesia using the neutron tomography technique. Characterization of the porosity using X-ray tomography technique also has been done in order to compare the results. The results show the neutron tomography technique is useful to visualize and characterize the porosity inside the limestone.
Synthesis TiO2-Ag thin film by DC Sputtering method for dye degradation
Authors: Andriyanti Wiwien , Nurfiana Fifi , Sari Anisa Novita , Kundari Noor Anis , Aziz Ihwanul
Published: February 2020

Titanium dioxide (T1O2) is well known as the most active and stable semiconductor as an environmentally friendly photocatalytic material to degrade pollutants in aqueous and gas. In this research, TiO2 thin film was synthesized on a stainless steel surface using DC sputtering method. To enhance the photocatalytic activity, the TiO2 thin film was doped with a silver (Ag) also using DC sputtering method. The surface morphology, chemical composition, and crystal structure of the thin film were characterized using scanning electron microscopy –energy dispersive spectroscopy (SEM-EDX) and X-rays diffraction (XRD), respectively. Based on SEM-EDX analysis, it’s found that the content of silver (Ag) is 10.5 % weight or 2.56 % at.. This condition was achieved for 2 minutes of deposition time. The photocatalytic activity of TiO2 and TiO2-Ag thin film was studied using UV light and sunlight. As a model pollutant, it’s used methylene blue. It’s found that, if the film exposure using UV light, the absorbance for TiO2 film is 35.85 % and 64.26 % for TiO2-Ag thin film. If the film exposure using sunlight, the absorbance for TiO2 film is 17.5 % and 76.74 % for TiO2-Ag thin film. It can be concluded that the effect of Ag doping can enhance the photocatalytic activity of the thin film.
Indoor Radon measurements in Madura dwellings
Authors: Wahyudi  , Winarni I D , Wiyono M
Published: February 2020

Indoor radon concentration in Madura Island region, East Java Province, has been mapped and determined. The obtained data is useful for health policies of radon in Indonesia and can be used as internationally baseline data through UNSCEAR, IAEA, and WHO. The mapping process has been done using a grid system of 20 km x 20 km, where on each grid there are 5-10 passive radon detectors using CR-39 installed in the houses for 3 to 4 months. After the exposure time, the detector CR-39 is etched using a 6,25 N NaOH solution at 70 °C in the oven for 7 hours to grow traces of alpha particles from radon. The imprints are read using a microscope with 400x magnification. The number of trace amounts of alpha particles in CR-39 shows the amount of radon concentration in the house. It was found that radon concentrations on Madura Island were in the range of 15.11 ± 1.07 Bq m − 3 to 126.93 ± 8.98 Bq m − 3 with an average of 58.74 ± 4.15 Bq m − 3. Radon concentration data in the house and GPS location were then entered into MapInfo Software v.10.5 for a radon distribution map. This research obtains the Regional Map of radon in Madura Island as a part of the indoor radon map in Indonesia.
Effect of drought stress on morphological, anatomical, and physiological characteristics of Cempo Ireng Cultivar Mutant Rice (Oryza sativa l.) strain 51 irradiated by gamma-ray
Authors: Patmi Y S , Pitoyo A , Solichatun  , Sutarno
Published: February 2020

Drought stress is a factor that affects plant growth and development, both in terms of morphology, anatomy, and physiology. Mutant Oryza sativa L. strain 51 of Cempo Ireng cultivar as the result of gamma-ray irradiation is superior mutant black rice strain which has a faster planting period of 10-20 days than its control and shorter plant height. This study aims to determine the morphological, anatomical, and physiological responses, especially the proline content inside the leaves of mutant black rice strain 51. The study used a completely randomized design (CRD) with the treatment of drought stress using PEG 6000 in Yoshida liquid media. The seedlings were planted for 21 days in untreated media, then treated for 14 days. Observation of morphological characters was carried out by measuring plant height, root length, leaf area, and plant biomass. Observations of anatomical characters were carried out by observing the cross-section of the root. Observation of physiological character was carried out by measuring leaf proline levels. The results showed that drought stress with PEG 6000 inhibited the growth and development of mutant rice strain 51. Drought stress reduces plant height, root length, leaf area, plant biomass and the area of root aerenchyma. Proline leaf content increased significantly at a PEG concentration of 30%. Mutant rice strain 51 showed a tolerant response to drought stress with the significant increased of proline, the increased of root stele diameter and the constant number of metaxylem.
Analysis Distribution of 32P Radioisotope in Silicone Patch Using Autoradiography Scanner
Authors: Rahman Wira Y. , Sarmini Endang , Pujiyanto Anung
Published: February 2020

Silicone patch has active ingredient of radioisotope Phosphorus-32 (32P) in the form of chromic phosphate (Cr32PO4). Radioisotope 32P is a β− (beta) emitter radionuclide with an energy of 1.71 MeV, having a half-life (T½) 14.3 days. A silicone patch with radioactive content of the radioisotope 32P has been used for keloid therapy. Radioisotope 32P as an active substance releases beta emitter continuously which causes the death of fibroblast and inhibits cell proliferation from keloid. In order to provide more optimal results, the distribution of chromic phosphate in silicone patches should be spread evenly. In this case, it provides a good therapeutic effect because of the energy of beta emitter is being released uniform. A chromic phosphate can be made from chromic acid reduction (redox) and phosphoric acid-containing radioisotope 32P by reducing Chrom VI to Chrom III using sodium sulfite (Na2SO3) reducing agent. In this study, we will determine the distribution of radioisotope 32P in silicone patches using an autoradiography scanner. Data from enumeration results were calculated statistically to obtain a relative standard deviation (RSD). The result shows that silicone patch sample has RSD of 0.036% with an average value of 14009482.6 ± 5041.4DLU (digital light unit) for lane and column size (10 x 14).
Qualitative Analysis of Long-Lived Residual Radioisotopes in 18 MeV Proton Bombarded Enriched Water Target
Authors: Kambali I , Suryanto H , Rajiman  , Parwanto  , Rindiyantono F , Billah A A , Pasha
Published: February 2020

Residual radioisotope analysis as a result of cyclotron-based 18F production is of paramount importance since it relates to the radiation safety of patients as well as radiation workers. In this investigation, 18-MeV proton beams were employed to irradiate enriched water (H2
18O) target for 18F production while Talys Evaluated Nuclear Data Library (TENDL) 2017 were used to study the origins of the radionuclide impurities. Gamma rays emmitted by the residual radionuclides were detected using a gamma ray spectroscopic system following a month of decay while their origins were analyzed from the TENDL 2017 nuclear cross-section calculations. Experimental results indicated that several long-lived radionuclides such as 109Cd, 57Co, 57Ni, 58Co and 56Co were recorded by the gamma ray spectroscopic system. The long-lived residual radionuclides were presumably due to proton interactions with Havar window and Silver body. Using the TENDL 2017-calculated nuclear cross-sections, it was discovered that several nuclear reactions responsible for the residual radioisotopes include 109Ag(p,n)109Cd which corresponded to the generation of 109Cd radioisotope, 60Ni(p,α)57Co and 58Ni(p,2p)57Co reactions for the formation of 57Co, 58Ni(p,d)57Ni reaction for the production of 57Ni radioisotope, 58Fe(p,n)58Co reaction for the generation of 58Co, and 56Fe(p,n)56Co reaction for the formation of 56Co. This experimental result can be used as a reference for future production of 18F and other radioisotopes should Havar window and silver body are used in the target system.
Preparation and characterization of collagen-ciprofloxacin HCL membranes produced using gamma irradiation as a candidate for wound dressing
Authors: Lukitowati F , Abbas B , Erizal  , Redja I W , Febryani H A
Published: February 2020

Wound and bacterial infections are often found after periodontal surgery. Collagen has an important role in healing wounds. The purpose of this study is to produce a membrane film which has been antibacterial activity so that it can be developed as a candidate for periodontal wound dressing. Collagen from bovine tendons synthesized with the acidic method to obtain dry collagen. Dry collagen then dissolved to get a 2% collagen concentration and then mixed with ciprofloxacin HCl 0,1% (w/v) and poured on polyacrylic molds. The membrane is then irradiated by gamma rays irradiation at varying doses of 0, 15 and 25 kGy respectively. The irradiated membrane then characterized by its physicochemical properties in the form of functional group analysis, membrane pore size, water absorption, water vapor transmission, tensile strength and percent release of ciprofloxacin HCl. The result of the characterization is that the membranes didn’t show any significant changes in the functional group but show any significant changes in size membrane pores, water absorption, water vapor transmission rate, tensile strength, and percent release of ciprofloxacin hydrochloride after gamma rays irradiation.
Detection and measurement of obstacles on a track using color segmentation with background subtraction and morphological operation
Authors: Hamadi H , Supriyono  , Riansah D
Published: February 2020

The process of detecting objects in a path of the image frame is a complex process. Generally, the identification process to find out the condition of a track in the form of objects and the size of objects is done manually by humans, namely using measuring instruments such as rulers, etc. It requires long processing time, and is less efficient, besides that it cannot be done remotely in the form of monitoring on the computer from the camera in terms of measurement. This study aims to create a system of detection and measurement of obstacle on a track using color segmentation method with background subtraction and morphological operation as a result of decision support. This detection and measurement system consists of webcam image acquisition, video extraction, converting frames of RGB to HSV images, color segmentation with background subtraction, gray scaling and thresholding, morphological analysis to improve the results of segmentation, detection and measurement displayed in the form of a Graphical User Interface (GUI). The performance of the system was tested on two background color references in the form of black, namely the asphalt track and white, namely the concrete cement track. The result of testing with the black background, produces an accuracy value of 96%, and with a white background of 100%. The system results in measuring obstacle have an average length of accuracy of 96.16% and a height of 85% on a black background in the form of an asphalt track, and on a white background in the form of cement concrete track results in a length measurement accuracy of 95.99% and a height of 90.88% with the camera moving or fixed.
Neutron tomography study of a lithium-ion coin battery
Authors: Purwamargapratala Yustinus , Sudaryanto  , Akbar dan Fahrurrozi
Published: February 2020

Neutron imaging of lithium-ion coin cell battery was obtained using tomography technique at Neutron Scattering Laboratory in Multi-Purpose Research Reactor G. A. Siwabessy (RSG-GAS) Serpong facility. The coin cell battery was CR2032 (20d x 3.2t mm) type consisted of positive and negative cases made of stainless steel, a cathode layer from lithium Ferro phosphate coated on aluminum foil, polyethylene film as separator, lithium hexafluorophosphate solution in ethylene carbonate and diethyl carbonate as electrolyte, an anode layer from graphite coated on copper foil, and spacer as well as spring made of stainless steel. The neutron tomography was used to observe the inside structure of the full charged coin cell. The observation was carried out with a neutron flux of 107 n/s.cm2 at 15 MWatt of reactor power. The image of the object is obtained by a Charge Coupled Detector (CCD) and the reconstruction software based on a filtered back-projection algorithm. The neutron imaging clearly shows the cell structure inside the casing. Even though the cell is not at the center of the casing, but it appears that the cell component consists of a cathode, separator and anode neatly arranged. The cross-cut image shows the important role of spring and spacer in improving the contact between cell and casing. The results showed the ability of neutron tomography techniques at RSG-GAS to investigate in detail the inside structure of a coin battery without disassembly (non-destructive test).
Effect of projections number on the image quality of industrial parallel beam gamma tomography
Authors: Azmi Bayu , Stefanus Megy
Published: February 2020

Gamma tomography technique can provide cross-sectional visualization of an object that needed for investigating pipe scale in geothermal power plants. Parallel beam tomography has advantages such as a simple system so that it is easier to apply in the field, but the scanning duration is relatively long. This paper discusses the effect of projections number on the reconstructed images quality and proposes the number of most effective projections for pipe scale investigation. Geothermal pipe sample (OD = 275 mm, t = 10 mm) with scale has been scanned with a parallel beam gamma tomography system. The system consists of a gamma radiation source (137Cs, 80 mCi), scintillation detector, motorized gantry, control module, data acquisition, and computer. The images were reconstructed with six different projections: 128, 64, 32, 16, 8, and 4 projections and the scanning duration: 530.8, 258.9, 127.9, 63.5, 31.7, and 15.8 minutes, respectively. Visually, the 128 projections data produces the smoothest image, whereas 64 and 32 projections images look almost the same. The 16 and 8 projections images are still able to distinguish between the pipe wall, scale, and void even though the 8 projections image looks very blurry. Then, the 4 projections image is not able to visualize the shape of the object. The gaps between the average pipe wall and void gray-scale pixels value of 128, 64, 32, 16, 8 and 8 projections images are 175, 174, 167, 153, 106, and 45, respectively. Based on the scanning duration, visualization, and the gray contrast, then the number of most effective projections is 32.
The effect of chitosan radiation of spinach plant based on agronomy characteristics on hydroponics floating system
Authors: Dewi Azri Kusuma , Aulya Dinda Zarra Zenitta , Suryadi Edy
Published: February 2020

Oligo chitosan is chitosan with a low molecular weight that derived from the extraction of shrimp shells which are irradiated using gamma radiation. The growth hormone content in oligo chitosan is able to increase the growth and production of crop cultivation on conventional agriculture. The oligo chitosan application is generally sprayed on plants, especially on the leaves and stems of plants. This research aims to find out the most influential method of oligo chitosan application if it’s applied to the cultivation of hydroponic floating raft systems, also to explain the effect of the application of oligo chitosan on the growth and production of spinach plants in the cultivation of the hydroponic system. There are three different ways of treatments in this study applying oligo chitosan to floating raft hydroponic system, which are sprayed out on plants (P1), dissolved in hydroponic nutrient solutions (P2), a combination of both (P3), and accompanied by controls. The oligo chitosan concentration given was 100 ppm in each treatment. The method used in this research is a descriptive comparative method, using primary data which is then analyzed quantitatively by using graphs and T-test. The results of this research were the application of oligo chitosan influences the growth and production of spinach plants to the hydroponic floating raft system. The treatment of oligo chitosan dissolution in the hydroponic nutrient solution (P2) was the treatment that gave the best influence to the height of the plant, number of leaves, and the amount of the yield of spinach compared to the other treatments. The width of the leaf does not have a significant effect on each treatment given.
Neutron diffraction and the residual stress distribution of magnesium processed by equal channel angular pressing
Authors: Rifai Muhammad , Mujamilah  , Muslich Muhammad Refai , Ridwan  , Sarr Mouhamadou Moustapha , Miyamoto Hiroyuki
Published: February 2020

Neutron diffraction and the residual stress distribution of magnesium processes by equal channel angular pressing was investigated in term of the grain refinement process. Magnesium is one of the metallic material for a biomedical implant due to the biodegradable properties. The structure and strength of biodegradable metallic material are quite essential to discuss for biomedical implant purposes. The ultrafine-grained structure of magnesium was prepared by equal channel angular pressing until four passes by route Bc at 523 K. The specimen was characterized by electron backscattering diffraction for the structure and neutron diffraction for residual stress. The grain refinement happened during the equal channel angular pressing on magnesium. The texture after four passes of ECAP shows a random orientation compare to coarse grain. The result shows that the strength of the ultrafine grain structure is lower than the coarse grain structure due to the crystal structure of magnesium as hexagonal. The other reason is that the distribution of residual stress on ultrafine grain bulk specimens, which measured by neutron scattering facilities.
Characteristic of natural radionuclide in the rivers of palembang, pontianak and palangkaraya
Authors: Suhariyono Gatot , Winarni Ilma Dwi , Mellawati June
Published: February 2020

River water is very beneficial for households and industries. River functions for households are include drinking, washing, bathing, transportation and tourism. River functions for the industry are electrical energy sources, irrigation, aquaculture, transportation of industrial products and others. Therefore, the characteristics of the Musi River in Palembang, the Kapuas River in Pontianak, and the Kahayan River in Palangkaraya, need to be researched, especially the natural radionuclide content. Water is taken 1 liter each with a plastic container at several sampling locations every 3 km along the river, especially water located near the industry. Samples were taken to the laboratory, allowed to stand for a month, put in Marinelli 1 Liter and measured by gamma spectrometry. The measured radionuclides were Pb-201, Th-230, Th-234, Ra-226, Th-232, Th-228, U-238, K-40 and Cs-137. Radionuclides found in the three river waters are Ra-226, Th-228 and K-40. The concentrations of Ra-226 radionuclide in Palembang, Pontianak and Palangkaraya are 0.06-3.09; 0.02-3.92; and 0.09-4.07 Bq/L respectively. Th-228 concentrations in Palembang, Pontianak and Palangkaraya are 0.03-0.60; 0.05-2.32; and 0.061.09 Bq/L respectively. K-40 concentrations in Palembang, Pontianak and Palangkaraya are 0.19-1.99; 0.19-58.41 and 0.69-1.95 Bq/L. The average concentration of natural radionuclides found in the three river waters is still below the limit value of environmental radioactivity, according to PERKA BAPETEN No. 7 of 2013 namely Ra-226 (1 Bq/L), Th-228 (0.35 Bq/L), Th-232 (0.73 Bq/L), Cs-137 (0.25 Bq/L) and K-40 (1.104 Bq/L).
Assessment of heavy metals pollution in the sediment of Ciliwung river
Authors: Mulyaningsih T R , Irmawati M , Istanto  , Alfian
Published: February 2020

Thirteen (13) rivers flowing in the city of Jakarta and Ciliwung is one of them. This river flows through residential, offices, industrial and factories. Activities that exist around the river can cause rivers to become polluted. River sediments act as a potential sink for many hazardous chemicals that can be used as indicators for pollution monitoring of the river. The objective of this study is to assess the heavy metal contamination in the Ciliwung river sediment based on single and combination indices. For the assessment of the Ciliwung sediment quality, measurements of metal concentration in river sediments have been performed. Sampling was carried out at four sampling locations, namely in Kelapa Dua, Kalibata, Condet, and Depok. Analysis of heavy metals in the sample was carried out using instrumental neutron activation analysis method. The analysis result shows that the detected elements in sediment include: Br, Al, As, Ca, Ce, Cr, Co, Cs, Mg, Mn, Na, Sb, Eu, Fe, Hf, K, Sc, Sm, Ta, Tb, Th, Yb, and Zn. The assessment based on the value of the enrichment factor indicates that there has been an increase in the concentration of heavy metals As, Cr, Sb, and Zn in moderate levels due to anthropogenic factors. Based on the geo accumulation index value, it is known that the sampling area is not polluted to moderate contamination. Heavy metals As, Cr, Sb, and Zn in sediments provide a low level of ecological risk to the aquatic environment. Based on the pollution load index value (PLI), all sampling locations are in no pollution conditions. From the evaluation, it can be seen that even for some heavy metals namely As, Cr, Sb, and Zn has been an increase in the concentration value but has not yet reached the polluted level and the ecological risk of heavy metals in the sediments also still provides a low ecological risk.
Safety Study of topaz irradiation management at the in core RSG-GAS Position
Authors: Sihombing Edison , Prasuad W.
Published: February 2020

Safety study of topaz irradiation management at the core rsg-gas position. A study of the management of Topaz stones in the irradiation process in the core position of the Multipurpose reactor G.A Siwabessy in the Batan Serpong (PRSG) has been carried out. A complex process of management because it must meet the technical and administrative requirements of the nuclear power supervisory body (BAPETEN), national and international transportation, and its safety management aspects. From the results of a study of hazard control and risk assessment (HIRADC) a risk rating with rating B is obtained, fulfilling the exposure aspect of container surface according to international transportation requirements (IATA) of <0.4 micro Sv/hour, production requirements as well as fulfilling transportation permits In a predictable safety aspect, a management strategy has been made so that the potential hazards can be overcome, because the results of this study show that Topaz management in in-Core positions with acceptable risk and supervision is required. fulfill administrative requirements, permit the production and be safe for the executor, transportation and environment and fulfill the requirements for re-export.
Design of low-flow oxygen monitor and control system for respiration and SpO2 rates optimization
Authors: Puspitasari Ayu Jati , Famella Deshinta , Sulthonur Ridwan M , Khoiri M
Published: February 2020

The importance of respiration rates and oxygen saturation (SpO2) monitoring and the high need for oxygen therapy opens the opportunity for the development of non-invasive respiration rate and oxygen saturation monitoring and controlling system. There are two modes of controlling in this system, automatic and manual mode. In automatic mode, the oxygen flow rate is based on the measurement of the respiration rate using the MLX90614 temperature sensor and tidal volume determination based on the patient’s body weight. Oxygen flow control uses a DC motor to open and close the oxygen regulator valve. Oxygen flow will stop when the respiration rate and oxygen saturation level are normal. Oxygen saturation is measured using the MAX30100 sensor. The fabricated regulator control system is capable of flowing oxygen by 5-8 liters per minute using an oxygen mask. The respiration rate measurement was compared with the palpation test, and the deviation was 0.99%. Oxygen saturation reading that used MAX30100 as an oximeter sensor was compared with pulse oximeter fingertip reading, and the deviation was 1.62%. The average flow deviation between the fabricated regulator control system and the calibrated regulator is 2.93%. The result of measuring the response time of the motor for an increase of one liter per minute (LPM) is 1.54 seconds.
A study on radiation dose estimation of argon-41 and nitrogen-16 airborne released from the Kartini research reactor
Authors: Salam M , Elisabeth S
Published: February 2020

A study on radiation doses estimation of Argon-41 and Nitrogen-16 airborne released from the Kartini research reactor is already carried out. Kartini reactor is a research reactor with the operating license of 100 KW. Estimation of radiation doses due to the radionuclide released in the airborne from the operating reactor is absolutely needed. This study is performed in order to estimate the internal dose contributions of the Argon-41 and N-16 received by radiation workers as well as the society in the reactor vicinity and to ensure that their dose contributions to the environment are still below the allowable limit value. Argon-41 and Nitrogen-16 are the activation products of gases containing Argon and Oxygen dissolved into primary coolant and released through the ventilation system. The estimated doses were calculated based on the fraction of Ar-41 and N-16 released to the environment through a reactor stack. The discharge rate was calculated by the normal condition for 400 hours of reactor operating in one year. The results showed that the estimated dose for the worker in the reactor building was 0.403 μSv/year, while the society in the reactor building vicinity was 4.45 x 10−3 μSv/year. This value is very small compared to the dose constraint that appointed at Center for Accelerator Science and Technology which is 15 mSv/year for the radiation worker and 0.3 mSv/year for the society surrounding Yogyakarta Nuclear Facility.
Determination of Potassium in Foodstuffs Consumed in Mamuju Indonesia by Neutron Activation Analysis
Authors: As’ari A H , Yusuf S , Mulyaningsih T R
Published: February 2020

Potassium (K) is an essential nutrient and one of the main minerals in the blood as a counterweight to electrolyte and blood pressure. Decreasing K intake can be one of the causes of increased blood pressure. Mamuju is one area with high hypertension cases. Potassium is widely obtained from foodstuffs. In this study, food was collected from the markets in Mamuju Indonesia and analyzed using neutron activation analysis to determine K concentration. The results for the meat and egg category show that beef has a higher potassium concentration than chicken meat, and Negeri chicken eggs are higher than Kampung chicken eggs. For the vegetable category, six samples have very high concentrations of potassium, namely caisim, kemangi, fern leaves, chinese cabbage, spinach, and beans; and the spices namely turmeric and kencur have high concentrations of potassium. For the fish and seafood category, tilapia has the highest potassium concentration and the lowest shrimp. For staples, the highest concentration of potassium is found in potatoes, the lowest in sticky rice; and the processed soybeans, tempeh has a higher potassium concentration than tofu. Therefore, it is important to pay attention to daily potassium intake by looking at the combination of food and potassium concentration in it, such as by increasing consumption of vegetable foods. On the other hand, high potassium intake needs to be followed by a reduction in sodium and salt intake in food.
Non-destructive Evaluation of Nuclear Grade IG-110 Graphite Using Constant Potential X-Ray
Authors: Himawan R. , Sutrasno  , Santoso S.B.
Published: February 2020

The main structures of the High Temperature Gas-cooled Reactor’s core are made of graphite material. High temperature and the high flux of neutron exposure in the HTGR reactor affects the integrity of graphite material. In order to ensure the integrity of the graphite materials, and in-service non-destructive inspection is needed. Commonly, prior to the operation, the radiography technique is conducted to evaluate the graphite material. The aim of this study is to develop a non-destructive inspection method in order to evaluate the quality of graphite materials. Five specimens made from nuclear grade graphite IG-110 produced by Toyo Tanso, Co. Ltd has been radiographically tested using X-ray constant potential machine to evaluate the graphite material. The parameter of the energy and intensity of X-ray has also been used in this computed radiography technique with a white type of phosphor imaging plate. A scanning machine of HD CR 35 NDT with 50 μm laser size and a 300 rpm scan rate equipped with a 16-bit system has been used to result in the digital image of the graphites. The results show that the increase of energy and intensity of the radiation to some extent produces better image contrast. The radiograph of the specimens also shows that there is no defect in the material. According to these results, it could be concluded that the digital radiography technique is appropriate for evaluating graphite material.
Validation and calibration of efficiency of various standard source for radioactivity analysis of gamma soil samples
Authors: Purnama D S , Akbari M K
Published: February 2020

Gamma Spectroscopy is one of the instruments used in measuring the radioactivity of environmental components. However, an efficiency value from the gamma spectroscopy detector is needed in order to obtain an accurate measurement. Efficiency calibration of the detector can be determined from the calibration curve of the standard source used. The calibration curve of a standard source can be affected by the matrix. The study aims to examine the two of the adjacency matrixes from various standard source for radioactivity analysis of gamma soil samples. The efficiency calibration of standard matrix sand (EG-ML) and ore (IAEA-RGU-1) are y = 3.1761x−0,838 and y = 4.3459x−0,913 respectively. The qualitative measurement of the radioactivity analysis was not influenced by differences in the two standard sources used, where the analyzed soil samples contained K-40, Bi-212, Pb-212, Bi-214, Pb-214, Ra-226, and Ac-228 which were natural radionuclides. However, the quantitative results of radioactivity values show differences with a percentage of 1.1% to 26.2% respectively. The validation of the method carried out on each EG-ML and IAEA RGU-1 standard source obtained satisfactory results with a bias value of ⩽ 2% is 1.2% and 4.3%, the precision value of ⩽ 8% is 0.6% and 1.4%, and the value of Z ⩽ 2 is 0.32 and 0.03 respectively.