Suitable Application Method Research Articles

Evaluating circulating tumour cell enrichment techniques to establish an appropriate method for clinical application in glioblastomas.

Brain tumours reduce life expectancy for an average of 20 years per patient, the highest of any cancer. A third of brain tumour patients visit their GP at least five times before diagnosis and many of those are diagnosed late through emergency departments. A possible solution to this challenge is to utilise a "liquid biopsy" blood test designed for circulating tumour cells (CTCs). Such a test could be applied at a primary healthcare centre, contributing to informed decision making for diagnostic imaging referrals. Furthermore, it could also be applied at secondary health care centres for the ongoing monitoring of disease recurrence. There is increased interest in CTC enrichment methods as a potential approach for faster diagnosis and monitoring of disease progression. The aim of this review to compare four CTC enrichment methods - OncoQuick®, Screen Cell®, pluriBead® and Cell Search® - with the objective of identifying a suitable method for application in the clinical setting for the isolation of CTCs from glioblastomas.

Digestate Application Methods and Rates with Regard to Greenhouse Gas Emissions and Crop Conditions

Digestate is commonly used as a liquid organic fertilizer, as it contains nutrients that are important for plant growth and thus help reduce usage of mineral fertilizers. Since the digestate application leads to the release of greenhouse gases (GHGs) into the atmosphere, it is necessary to find a suitable application method and fertilizer rate with minimal gas emissions while providing sufficient nutrients to crops. The aim of this study was to investigate the relationship between selected GHGs and ammonia (NH3) release into the atmosphere and different rates of digestate applied, i.e., 0, 10, 20, 30, and 40 m3 ha−1. Two digestate incorporation methods were used, i.e., a disc application unit (D) and strip-till (S). The fluxes, i.e., methane (CH4), ammonia, and carbon dioxide (CO2), were monitored using the wind tunnel method. Crop growth and potential nutrient utilization by silage maize were assessed through stand condition monitoring by the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) using remote sensing. Under the given conditions, the digestate rates and the compared application methods had significant effects on the level of fluxes. The rate of digestate was confirmed to affect the yield of silage maize. The yield increased by more than 8% when using the disc applicator. Based on our results, it is advisable to apply digestate by strip-till technology at rates of approximately 20 m3 ha−1.

CoFe2O4 decorated graphene/C18-functionalized mesoporous silica nanocomposites prepared for magnetic enrichment and electrochemical detection of promethazine in beef

Promethazine (PHZ) is used as a sedative in veterinary medicine, and its residue can threaten the health of human. The electrochemical detection of PHZ is suitable method for application in the field. However, the traditional electroanalysis is difficult to perform directly in meat samples due to matrix interference. This work integrates magnetic solid-phase extraction and differential pulse voltammetry for highly sensitive and selective determination of PHZ in beef and beef liver for the first time. CoFe2O4/graphene coated with C18-functionalized mesoporous silica (MG@mSiO2-C18) is synthesized as dispersed magnetic adsorbent to extract PHZ. Magnetic glassy carbon electrode modified with nitrogen-doped hollow carbon microspheres (HCM) attracts the MG@mSiO2-C18 with PHZ, and directly detects the PHZ without elution procedure. MG@mSiO2-C18 can separate PHZ to avoid the interference of impurities on following detection, and also concentrate PHZ on magnetic electrode. Additionally, the electrode modification with HCM can amplify the electrochemical signal of PHZ. Finally, the integrated PHZ determination method exhibits a wide linear range from 0.08 µmol/L to 300 µmol/L with a low limit of detection of 9.8 nmol/L. The beef sample analysis presents excellent recovery, demonstrating that this protocol is promising for the rapid and onsite detection of PHZ in real meat samples

A Discussion on Utilization of Zinc Anode Applied in Cross-section Repair of RC Member Damaged by Chloride Attack - Time-Lag Application of Different Zinc Anodes -

This paper discusses the effectiveness of zinc anode cathodic protection applied to RC beam specimens severely damaged by chloride attack. Based on the experiment, that is, the zinc anode cathodic protection is applied to the 41-year-old RC beam specimens exposed to natural marine environments, suitable application method of zinc anode is discussed. In the experiment, repair was performed in three stages. In the first stage, polymer-modified mortar was cast to replace existing concrete in the middle tensile part with zinc anodes embedded in the repair mortar. After protective current became stable value, the anodes were disconnected from steel bars for a year defined as the second stage. During the one year of second stage, the steel bar in the repair area remained be passive state, without any sign of corrosion. As for the third stage, additional zinc anodes were installed in the existing concrete part in order to protect the steel in old chloride contaminated concrete. From one-year observation after the application of zinc anodes in old concrete part, it is confirmed that “time lag application” could stop the corrosion of steel bar in both parts.

Overview of statistical methods of process monitoring

At present, process monitoring by comparing the current parameters against a specified setpoint is widespread at thermal power plants. This approach does not allow diagnosing the emergence of a trend leading to an emergency mode at early stages. On the other hand, the analysis of time series of parameters by means of methods of statistical process monitoring allows detecting deviations from normal mode of equipment operation before emergency conditions appear. The purpose of this work is to analyze existing works in the field of application of statistical methods of monitoring. A systematic literature review (SLR) method was used in the analysis. The research process included clarifying research questions, searching for articles in databases, and forming article evaluation criteria. The specifics of the process at TPPs, which impose restrictions on the application of individual methods of statistical monitoring, were formulated. The study resulted in 64 publications, which were filtered and classified into rating groups. The highest ranked articles were used to determine the most effective statistical monitoring methods to be used on thermal power equipment. The answer to the questions posed in the study also reveals the existing problems of applying statistical methods of monitoring. The results of the study will help to identify the most applicable statistical methods for thermal power industry. It is concluded that the most suitable methods for application on thermal power equipment are methods of control charts (both Shewhart charts and Hotelling charts) based on either process parameters or generalized variance, as well as the use of autocorrelation models.

The influence of using wet cellulose poultice on nanolime consolidation treatments applied on a limestone

Consolidation treatment with nanolime is a common conservation intervention which needs more research to enhance penetration and mechanical properties while also minimizing the undesired white veil on the surface which significantly alters the surface appearance. In this light, the application of a cellulose poultice soaked in distilled water over the treated surface with nanolime tries to prevent the formation of white hazes and to favour nanolime carbonation and penetration in the pore structure. However, the real influence of this practice on the consolidation effectiveness has never been studied yet and is not yet well understood. In order to provide more insights about its most suitable application method, in this study, we investigated the effectiveness of a wet cellulose poultice for two different nanolime consolidation treatments on a weathered limestone. Nanolime has been synthetized by anion exchange processes and dispersed in two mediums: i) water and ii) 50% v/v of water and alcohol. The influence of the poultice on the penetration and aesthetic properties has been studied by drilling resistance measurement, ultrasounds test, stereomicroscopy, measurements of roughness and static contact angle, spectrophotometry and scanning electron microscopy (superficial and cross sectioned samples). Additionally, consolidation effectiveness has been evaluated through the changes in apparent density, open porosity, porosity network in the outer 5 mm of the surface by mercury intrusion porosimetry and surface cohesion by the peeling test. Results show that, contrary to what is usually assumed, samples where a wet cellulose poultice was applied after the consolidant reached the lowest penetration levels and retained lower dry matter in comparison to their counterparts without poultice. A consolidation treatment with nanolime is more complex that it is generally considered, and the application of poultices is not always enhancing consolidation level; the most suitable application procedure must be chosen with regards to the nanolime and substrate specific characteristics.

The Effect of Application Method and Dosage of Manure on Growth and Yield of True Shallot Seed in West Sumatera

To increase shallot productivity, it is necessary to apply true shallot seed (TSS) cultivation technology. This study aimed to determine the suitable method of application and dosage manure in increasing the bulb yield of true shallot seed. The research was conducted at the Experimental Garden of Sukarami AIAT, West Sumatera (altitude 1000 m above sea level and soil type Andosol). The research arranged using a Split Plot Design in randomized blocks, each with 3 replications. Main plot treatment (A) is a application method of manure which consists of 2 types, namely: A1 (given in a spread) and A2 (given in the planting hole). While the treatment of subplots (B) was the dosage of cow manure consisting of 6 types, namely: B1 (0 t/ha), B2 (5 t/ha), B3 (10 t/ha), B4 (15 t/ha), B5 (20 t/ha) and B6 (25 t/ha). The seeds of the Lokananta variety were six weeks after sowing, planted at a spacing of 10x10 cm, 1 seedling/planting hole, on a plot measuring 5x1 m. The results showed that there were highly significant interactions were only found in bulb weight per clump and bulb diameter. The highest dry bulb yield was obtained at a dosage of 15-25 t/ha of manure. In order to make farming activities more efficient, it is recommended to use 15 t/ha of cow manure with the application method by spreading or in planting holes in the cultivation of true shallot seed in West Sumatera.

A simple method for the application of exogenous phytohormones to the grass leaf base protodermal zone to improve grass leaf epidermis development research

BackgroundThe leaf epidermis functions to prevent the loss of water and reduce gas exchange. As an interface between the plant and its external environment, it helps prevent damage, making it an attractive system for studying cell fate and development. In monocotyledons, the leaf epidermis grows from the basal meristem that contains protodermal cells. Leaf protoderm zone is covered by the leaf sheath or coleoptile in maize and wheat, preventing traditional exogenous phytohormone application methods, such as directly spraying on the leaf surface or indirectly via culture media, from reaching the protoderm areas directly. The lack of a suitable application method limits research on the effect of phytohormone on the development of grass epidermis.ResultsHere, we describe a direct and straightforward method to apply exogenous phytohormones to the leaf protoderms of maize and wheat. We used the auxin analogs 2,4-D and cytokinin analogs 6-BA to test the system. After 2,4-D treatment, the asymmetrical division events and initial stomata development were decreased, and the subsidiary cells were induced in maize, the number of GMC (guard mother cell), SMC (subsidiary mother cell) and young stomata were increased in wheat, and the size of the epidermal cells increased after 6-BA treatment in maize. Thus, the method is suitable for the application of phytohormone to the grass leaf protodermal areas.ConclusionsThe method to apply hormones to the mesocotyls of maize and wheat seedlings is simple and direct. Only a small amount of externally applied substances are needed to complete the procedure in this method. The entire experimental process lasts for ten days generally, and it is easy to evaluate the phytohormones’ effect on the epidermis development.

Phenology, Growth, Yield and Nitrogen Uptake of Wheat in Response to Nitrogen, Potassium and Their Application Methods

Application of macronutrients in less amount along with improper application method(s) are the major factors for low yield. Experiments were designed with the objectives to determine the optimum rate of nitrogen (N) and potassium (K) along with suitable application method to minimize nutrients losses. The experimental site was New Developmental Farm of the University of Agriculture Peshawar and experiments were conducted for two consecutive years i.e. 2010-11 and 2011-12. After analysis, the results indicated that both N and K significantly affected days to phenology (anthesis and maturity). Days to phenology increased linearly with increase in rate of N and K and more days to phenology were recorded when both were at their highest rates. Similarly plant height, leaf area/tiller, flag leaf area, leaf area index, leaf area duration, grain yield, N uptake by grains and straw were increased with increasing level of N and K and attained maximum value when N and K was applied at the rate of 180 and 90 Kg/ha, respectively. Nutrients application method significantly affected plant height, leaf area/tiller, flag leaf area, grain yield and N uptake by straw and grains with maximum values for these traits were recorded when nutrients (N and K) were applied in such a combination that 15% nutrients were supplied through foliar and 85% through soil application. Application methods had a non-significant effect on days to phenology, leaf area index and leaf area duration. It is concluded from the results that application of N and K at the rate of 180 and 90 Kg/ha respectively in such a way that 15% is applied through foliar spray and 85% through soil application improved growth, yield and N uptake of wheat crop under the semi-arid climate.
 

Application of Herbal Essential Oil Extract Mixture for Honey Bees (Apis mellifera L.) Against Nosema ceranae and Nosema apis

Abstract In recent years, interest in herbal essential oil extracts for the treatment of nosemosis has steadily increased. The great importance of this study is in evaluating and validating the synergistic effect caused by the mixture of different herbal extracts. The aim of the study was to investigate through cage experiments and field studies the effect of mixed herbal essential oil extracts and to determine the most suitable application methods and doses of the product in the treatment of nosemosis. The duration of the experiments was three weeks. Results show that the herbal essential oil extract mixture (HEOEM) is effective on both Nosema apis and Nosema ceranae, and on the two together (mixed infection). With respect to application methods, the results revealed that the most suitable method is spraying HEOEM with sterilized distilled water on adult bees and on both sides of frames; 500 µL per cage and 2,000 µL per frame were found to be effective doses of HEOEM in the experimental cages and hives. HEOEM can be a viable alternative to synthetic products in the immediate future as the contents are natural and have no toxic effect on honey bees.

Review of electrodeposition perspectives towards anticorrosion mitigation of mild steel

The study of corrosion is vital to reducing the overhead costs in the manufacturing industries. However, finding suitable application methods for prevention is a concern due to manufacturer specification and resource investment procedure. The coating is recognized as one of the foremost ways of applying resistance to corrosion damage. Electrodeposition is a unique technology because of its fine control of the chemical properties, mechanical strengthening behavior, and structural evolution over time. Thus, these overview studies discuss the possible protective coatings, corrosion as a major problem and its protection methods, electrodeposition process, and inherent characteristics. It intricacy of mild steel structural responses and its efficacy was also established.

Evaluation of Plant Growth Parameters by In vitro and Ex vitro Inoculation of Micropropagated Banana Plantlets with Rhizospheric and Endophytic Bacterial Inoculum

Banana propagation is dependent on propagation by tissue culture for industrial purposes. Due to lack of native endophytes in tissue culture plantlets, reintroduction of beneficial microorganisms to tissue culture plantlets become popular as a useful foundation for improving the level of establishment, increasing plant growth parameters, protecting the plantlets against pest and diseases and overall performance for field plantation. In the present study, rhizospheric and endophytic four bacterial species (Pseudomonas fluorescens, Bacillus putida, Bacillus pumilus, Bacillus amyloliquefaciens were isolated from different parts of healthy banana plants such as root, leaf and pseudostem. Banana tissue culture plantlets were cultured for root formation stage on MS medium and used as host for artificial inoculation. Then, bacterial inoculation was carried out with tissue culture plantlets both in vitro and ex vitro conditions. All banana plantlets used for this experiment were successfully acclimatized and survived in the greenhouse. The experiment consisted of three treatments: (1) bacterial inoculum with in vitro rooted plantlets for 2 weeks (2) bacterial inoculum with ex vitro (hardening) plantlets (3) control with sterilized distilled water. Among these treatments, in vitro inoculation affected significantly increased plant height, number of leaves and plant girth for all data collection times with the highest increment indices: (24.0, 7.0, and 7.3). Ex vitro inoculation showed the second highest increment indices: (22.0, 6.9 and 6.3) for plant height, number of leaves and plant girth, respectively. The lowest number of plant growth parameters were observed in control treatment for all four data collection time (19.0, 6.2, and 6.0). According to the results, application of mixtures of bacterial inoculum was effective for enhanced plant growth parameters of tissue culture banana plantlets under greenhouse condition. In addition, two weeks artificial inoculation during in vitro plantlets stage was found the most suitable method for application of microbes with tissue culture banana plantlets which can promote the microbial rhizosphere of banana prior to field plantation.

The impact of silver and chitosan nanoparticles on A. fumigatus isolates from Ras cheese and sputum of respiratory patients

This work was designed to study the incidence of A.fumigatus in Ras cheese sold in different markets at Sohag city, Egypt and also in sputum samples of respiratory diseases patients admitted to Sohag University Hospital, as well as study the effect of silver (SNPs) and chitosan (CNPs) nanoparticles against the A. fumigatus isolates. Potato dextrose agar (PDA) was used for mycological culture of samples and the antifungal effect of nanoparticles (with different concentrations) using well diffusion method. High resolution transmission electron microscope (HRTEM) was used for detection of nanoparticles size, and scanning electron microscope (SEM) was used for investigation of nanoparticles effect on A. fumigatus morphology. The isolation rate of A. fumigatus were 22.11 % (21/95), 32.17 % (37/115) from Ras cheese and sputum samples, respectively. SNPs had inhibitory effect at concentrations 1 and 2 µg/ml, and complete growth inhibition with concentrations 4, 8, and 16 µg/ ml. While CNPs had no effect in concentrations 1 and 2 µg/ ml, but at concentrations 4, 8 and 16 µg/ ml represented inhibitory effect with mean inhibition zones 5±0.21, 9±0.41 mm and 11 ±0.77mm, respectively. SNPs and CNPs by SEM patently damaged the A.fumigatus cell structure. Using nanoparticles against A. fumigatus from food and human sources is important to stop food spoilage and protect human health. So, further studies are necessary for the investigation of suitable application methods, and the expected hazards which may occur after nanoparticles usage.

Phosphorus Nutrient Management through Synchronization of Application Methods and Rates in Wheat and Maize Crops.

Management of inorganic fertilizer is very important to obtain maximum crop yield and improved nutrient use efficiency in cereal crops. Fixation of phosphatic fertilizers in alkaline soils due to calcareousness is one of the major hurdles. It induces phosphorus nutritional stress that can decrease the yield of maize and wheat. Selection of a suitable application method and proper stage of crop for phosphorus (P) fertilizer has prime importance in better uptake of P and crop production. Among different application methods, soil and foliar application are widely adopted. In wheat and maize, knee height + tasseling and stem elongation + booting are critical stages towards P deficiency. That is why field trials were conducted to evaluate the supplemental effect of foliar P on maize and wheat yields. For that, 144 mM KH2PO4 was applied as foliar at knee height + tasseling and stem elongation + boot stages in maize and wheat, respectively. Soil application of 0, 20, 40 and 60 kg P ha−1 was done through broadcast and band methods. Results showed that foliar spray of 144 mM KH2PO4 at knee height + tasseling and stem elongation + boot stages in wheat and maize significantly enhanced grains yield and phosphorus use efficiency (PUE) where P was applied as banding or broadcast at the time of sowing. A significant decreasing trend in response to increasing soil P levels validated the efficacious role and suitability of foliar P. In conclusion, the use of P as foliar at knee height + tasseling and stem elongation + boot stages is an efficacious way to manage P fertilizer.

Efficacy of Fungicides Applied for Protectant and Curative Activity Against Myrtle Rust.

Myrtle rust, caused by the pathogen Austropuccinia psidii, affects species of the Myrtaceae, many of which are endemic to Australia and New Zealand. Originating from South America, A. psidii is now present in both countries, necessitating effective chemical control for disease management. Using an artificial inoculation protocol, the efficacy of eight fungicides (tebuconazole/trifloxystrobin, cyproconazole/azoxystrobin, fosetyl aluminum, triforine, triadimenol, oxycarboxin, copper, and tebuconazole) applied as curative or protectant treatments was tested on two native New Zealand species (Lophomyrtus × ralphii and Metrosideros excelsa). The impacts of rate (×2), frequency (single or double), and timing (pre- or postinfection) of fungicide application were investigated. Overall, the most effective fungicides tested across both species were those that included a demethylation inhibitor and strobilurin mix, notably tebuconazole/trifloxystrobin (Scorpio) and cyproconazole/azoxystrobin (Amistar Xtra). These fungicides significantly reduced infection of host plants relative to the water control. Timing of application significantly affected bioefficacy, with applications made 7 days before inoculation or 7 days after inoculation being generally the most effective. The rate of fungicide application was not significant for both host species, with few interaction terms showing overall significance. Key findings from this study will set the foundation for further fungicide bioefficacy research conducted to evaluate formulations and adjuvant mixtures, determine suitable application methods for enhanced retention and coverage, and derive optimum application time for effective protection of native and exotic Myrtaceae species in New Zealand.

Efficacy of Bacillus thuringiensis Treatment on Aedes Population Using Different Applications at High-Rise Buildings.

Bacillus thuringiensis israelensis (Bti) is an effective biological insecticide for killing mosquito larvae. However, choosing the suitable application method for larviciding is critical in increasing its effectiveness. Therefore, this study aimed to determine the effectiveness of Bti (VectoBac®) WG using various applications at high-rise buildings. Three different applications of Bti treatment were applied at three high-rise buildings in Bandar Saujana Putra. The ULV machine is used for Pangsapuri Impian, a mist blower for Pangsapuri Seri Saujana and a pressured sprayer for BSP 21. BSP Skypark does not undergo treatment and acts as a control. The efficacy of Bti treatment was measured by analyzing the ovitrap surveillance data collected (POI and MLT) for pre and post-treatment. Post-treatment ovitrap surveillance indicates that the Aedes sp. mosquito density was lower than the density at the time of pre-treatment surveillance. Overall, the Aedes albopictus species in both an indoor and outdoor environment setting had shown a reduction. The highest Aedes sp. density reduction is seen through the use of mist blowers in outdoor settings for Aedes albopictus, (%POI reduction = 87.4%; %MLT reduction = 93.8%). The mist blower yielded results that is significantly higher compared to other larviciding applications; the order from greatest to the least was mist blower > pressured sprayer > ULV. It can be concluded that each application produces different degrees of effectiveness in reducing the Aedes sp. density in different environmental settings.

IEEE 1815.1-Based Power System Security With Bidirectional RNN-Based Network Anomalous Attack Detection for Cyber-Physical System

The introduction of the cyber-physical system (CPS) into power systems has created a variety of communication requirements and functions that existing legacy systems do not support. To this end, the IEEE 1815.1 standard defines the mapping between existing distributed network protocol networks and IEC 61850 networks that reflect new requirements. However, advanced CPS cyberattacks have been reported, and in order to address cyberattacks, security research on new power systems that use network devices and heterogeneous communication is necessary. In this study, we propose an intrusion detection system for an IEEE 1815.1-based power system using CPS. We 1) analyze an IEEE 1815.1-based power system network and propose a suitable application method for an intrusion detection system, 2) suggest a bidirectional recurrent neural network-based anomaly detection system for an IEEE 1815.1-based network, and 3) demonstrate the verification of the proposed technique using various power system-specific attack data, including real power system using CPS network traffic, CPS malware behavior (CMB), false data injection (FDI), and disabling reassembly (DR) attacks. Proposed technique successfully detected five types of CMB attacks, three types of FDI and DR attacks.

Effects of biochar application during different periods on soil structures and water retention in seasonally frozen soil areas

Currently, little is known about soil improvement by biochar in seasonally frozen soil areas. It is not clear whether the effects of biochar application on soil physical properties differ based on application period. Therefore, the purpose of this study was to explore the effects of biochar on soil structure and water retention in cold regions during different application periods. Three biochar applications during different periods were set up through field trials (A: in the early stage of freezing, B: in the middle period of thawing and C: addition of half of the biochar in the early stage of freezing and other half in the middle period of thawing), including four biochar application rates (3, 6, 9 and 12 kg·m−2), and no biochar was applied as a control (CK). The results showed that the selection of the biochar application period had a significant effect on the soil structure, but there was no significant difference in the stability of the soil structure. Biochar significantly increased the total porosity (TP) and the content of aggregates with diameters >0.25 mm in the soil, and all 9 kg·m−2 biochar treatments showed the best structural stability index. The improvement of the soil structure led to the enhancement of the water storage capacities. The plant available water content (PAWC) increased from 0.0638 to 0.0927–0.1767 cm3·cm−3, and this result was significantly related to the increases in soil TP and large aggregates (LAs: >2 mm). The optimum field capacity (FC = 0.372 cm3·cm−3) was obtained when the applied amount was 9 kg·m−2. This was beneficial for the stable storage of soil moisture. However, compared with the CK, none of the treatments in area B increased the liquid water content in the field soil. In summary, we suggest that treatment C9 is the most suitable method for application in seasonally frozen soil areas.

Design and experiment of noncontact eddy current damping module in air bearing–guided linear motion system

As a method for reducing the friction of high-precision system, air bearings have been widely used for various industrial applications. However, their small damping leads to poor in-position stability and therefore systems are susceptible to residual vibration and disturbance. In this study, a linear motion stage which is guided by air bearing for a noncontact eddy current damping module is proposed. The eddy current damping module consists of a Halbach array of permanent magnets and a fixed conductor plate. An eddy current is generated in the conductor in the direction opposing the change in the magnetic field when the magnets move, after which the resistivity in the conductor dissipates the kinetic energy of the moving part; therefore, the module has a damping effect without contact and system is shown good in-position stability. In order to specify the damping effect, the motion of the moving part was experimentally analyzed. The step response confirmed that the eddy current damping module can improve the performance of the positioning system: the settling time decreased by 36.8% and the resolution improved by 59.4%. These improvements verify that eddy current damping is a suitable method for application in precision industries.

A comparison of the quantification aspects of human reliability analysis methods in nuclear power plants

Human reliability analysis (HRA) is a method for evaluating human errors and providing human error probabilities (HEPs) for application in probabilistic safety assessment (PSA). Up to date, there has not been a universally accepted HRA method for estimating HEPs, because such acceptance still has several challenges, including 1) data scarcity for predicting HEPs, 2) limited representation of cognitive aspects of human performance, and 3) significant differences in HRA results from different analysts, even when applying the same method. Some comparison studies were conducted to study differences among the HRA methods, or to select the most suitable method for application in the corresponding fields. However, these studies have several weak points in understanding differences among HRA methods.This study compared quantification aspects of HRA methods. Four typically-used HRA methods were considered. Seven post-initiators having representative conditions for the OPR1000 type of nuclear power plants (NPPs) were analyzed. Then, an investigation verified quantification differences among the HRA methods. As a result, eight findings are described. The result of this study could help HRA practitioners like NPP utilities or regulatory agencies to 1) aid in the selection of the proper method for its intended use or application, 2) estimate ranges of HEPs when using these HRA methods and 3) use this result as a reference of HEPs.