Experimental Research Center Research Articles

EUCLID: A New Approach to Constrain Nuclear Data via Optimized Validation Experiments using Machine Learning

Compensating errors between several nuclear data observables in a library can adversely impact application simulations. The EUCLID project (Experiments Underpinned by Computational Learning for Improvements in Nuclear Data) set out to first identify where compensating errors could be hiding in our libraries, and then design validation experiments optimized to reduce compensating errors for a chosen set of nuclear data. Adjustment of nuclear data will be performed to assess whether the new experimental data—spanning measurements from multiple responses—successfully reduced compensating errors. The specific target nuclear data for EUCLID are 239Pu fission, inelastic scattering, elastic scattering, capture, nu-bar, and prompt fission neutron spectrum (PFNS). A new experiment has been designed, which will be performed at the National Criticality Experiments Research Center (NCERC).

The Antioxidant Effects of Sesamol on Bleomycin-Induced Oral Submucous Fibrosis

Objective: Oral submucous fibrosis (OSF) is a disease characterized by abnormal collagen deposition that causes inflammation and malignancy in oral mucosal tissue. Fibroblasts and myofibroblasts, are the cells that show significant activation in the development of OSF. Bleomycin (BL) is a chemotherapeutic agent commonly used in cancer treatment that also causes inflammatory changes in the oral mucosa, initiating fibrosis in the oral submucosal tissue. Sesamol (SE) has antioxidative and anti-inflammatory properties which are abundant in sesame seeds and sesame oil, and SE has a beneficial effect on the mucosal layer. This experimental study aimed to investigate SE’s effects on BL-induced OSF. Materials and Methods: The study obtained 18 healthy adult male albino rats aged 3-4 months and weighing 200-250g from Bolu Abant Izzet Baysal University’s Experimental Animal Application and Research Center. The rats were divided randomly into control, BL, and BL + SE groups (n = 6 in each group). A model of OSF was established in the rats by administering 0.5 mg/mL of BL and 50 mg\kg of SE to the BL+SE group each day. The hematoxylin and eosin stain and Masson’s trichrome stain were used to assess histopathological changes in the oral mucosa. Results: The results revealed SE to have beneficial effects on BL-induced OSF through its antioxidant and anti-inflammatory properties. Histopathological evaluations and biochemical analysis of oral submucosal tissue samples also revealed SE to provide statistically significant protection against fibrosis in the oral mucosa (p < 0.01). Conclusion: This study has demonstrated oral submucous fibrosis that develops due to BL as well as SE to have an antioxidant effect on OSF regarding BL-induced reactive oxygen species (ROS) activation and collagen synthesis.

Polymeric Approach to Adjuvant System in Antibody Production against Leishmaniasis Based on Hybridoma Technology.

Leishmaniasis is a zoonotic disease, which is one of the serious public health problems in the world. Nowadays, antibody production using hybridoma technology may be a correct approach in terms of sensitivity in the diagnosis of diseases such as leishmaniasis. The aim of this study was investigation of the effectiveness of different adjuvants on polyclonal antibody production against L. tropica based on hybridoma technique. Accordingly, Freund's adjuvant (1956, M. tuberculosis), as a classic adjuvant in studies, was used comparatively with the non-toxic polymeric based Polyoxidonium adjuvant. All animal immunization procedures were conducted at Bezm-i Alem University Experimental Animal Research Center. The adjuvant response was tested both in the serum sample and in the antibodies produced by the hybridomas. The antibody titers were determined with ELISA. Freund's and Polyoxidonium (PO) group blood titer's increased approximately 5.5 fold compared to control after the 6th and 8th immunization. Hybridomas produced from mice immunized with PO adjuvant induced only antigen-specific antibody response and did not develop an immune response against the adjuvant. Adjuvant selection is very important in terms of the specificity of antibody responses of cells produced in hybridoma technology. Therefore, PO is recommended as a new adjuvant system in this study.

Development and application of a full-scale mechanical rock-cutting platform for measuring the cutting performance of TBM cutter

With the massive development of mechanical equipment for underground space construction, understanding the cutting mechanism and measuring the cutting performance of various cutters used in tunnelling boring machine prior to the construction is vital for increasing tunnelling efficiency and reducing cost. Mechanical rock-cutting tests have been an indispensable method for investigating the cutting characteristics, which can be effectively used for guiding the mechanical excavation of underground engineering. In this paper, a novel full-scale cutting platform developed by Shanghai Shield Design and Experimental Research Center Co., Ltd is introduced. The rock types, rock structure types, cutter types, cutting radius, rotation speed, penetration depth, cutting modes, cutter spacing and cutter installation angle are considered and integrated into the design of cutting platform. Specifically, different cutters, including disc cutters, scraper cutters, shell cutters and pick cutters, can be considered in this platform. Moreover, the circular cutting mode can be conducted with cutting diameter ranging from 0 to 6.2 m, and the arc cutting method is originally proposed to perform a rotary cutting test with cutting diameter above 6. 2 m. Notably, a laser measurement method is newly performed to measure the rock surface profile and calculate the rock cutting volume in the rotary cutting mode. The rock-cutting platform consists of mechanical system, hydraulic system, cutterhead system, control system, data sensing and acquisition system. The measuring reliability and accuracy of the newly designed rock-cutting platform and laser measurement is experimentally verified by the rotary cutting tests on granite and mortar using disc cutter and scraper cutter. A critical cutting radius of 1000 mm for side force is acquired, and the effects of cutting radius and cutting depth are initially investigated. The development of the full-scale rock-cutting platform is an effective measurement method for cutting performance, which can provide data support for optimization of cutterhead layout and determination of working parameters.

Protective effect of Tulbaghia violacea extract on cardiac damage: deep circulatory arrest rat model

Objectives: Total circulatory arrest (TCA) technique is a method used in cardiac surgery accompanied by cardiopulmonary bypass (CPB). It has been shown that Tulbaghia violacea extract increases antioxidant capacity, regulates blood pressure, decreases lipid peroxide, and reduces atherosclerosis. In this experimental study, we aimed to investigate the effect of T. violacea extract administration on serum oxidative stress parameters (Total antioxidant status [TAS], total oxidant status [TOS] and oxidative stress index [OSI] and deoxyribonucleic acid [DNA] damage level with 8-Hydroxy-2-Deoxyguanosine [8-OHdG]) and histopathological changes in the heart and other organs in rats with deep circulatory arrest model. Methods: In this study, 48 Wistar Albino adult rats, 24 female and 24 male, obtained from Harran University Experimental Animals Research Center were used. The average weight of female rats was 250-300 g, and the average weight of male rats was 450-500 g. These rats were randomly divided into four groups. 6 male and 6 female rats were used in each group (Group 1 = Sham, Group 2 = Injury, Group 3 = Treatment and Injury, Group 4 = Treatment). Results: As a result of this experimental study, the changes in the biochemical 8-OHdG, TOS, OSI and TAS levels of the groups were found to be statistically significant (p < 0.001). In the subgroup analyzes of the data, 8-OHdG level, which is an oxidative DNA damage marker in Group 2 was higher than the Group 1, Group 3 and Group 4 and there was a statistically significant difference (p < 0.001, p = 0.027 and p < 0.001; respectively). The TOS level of the injury group was higher than Group 1, Group 3 and Group 4 and there was a statistically significant difference (p < 0.001, p = 0.003 and p < 0.001; respectively). Conclusions: As a result of our study, we revealed that T. violacea extract has a protective effect on organ and tissue damage in the TCA model.

Advancements in Yttrium Hydride Moderator Development

As microreactors evolve to become a more affordable and efficient worldwide energy source, the development of moderator material within the system to decrease the required mass of low-enriched uranium fuel is important. The use of low- instead of high-enriched uranium in small nuclear reactors stems from recent national policies associated with nonproliferation. New designs are being developed for a range of applications and nuclear space systems in particular. Using system geometries such as those described in this paper, the next step is to advance the technology readiness level of moderator material such as delta-yttrium hydride (YHx,x = 1.6–2.0) so that it can be qualified for use in a microreactor system. Although characterization of unirradiated material has been documented previously, to fully understand the performance of this material, behavior in relevant irradiation environments must occur. This paper describes the fabrication of yttrium hydride samples through innovative techniques and how these samples were tested in two relevant neutron environments. These two experiments include (1) a critical experiment performed at the National Criticality Experiments Research Center (NCERC) to evaluate reactivity changes in a neutron-critical environment and (2) irradiation in the Advanced Test Reactor (ATR) to assess structural integrity/material form, thermophysical data, hydrogen permeability, and other features post irradiation. For this purpose, hundreds of samples were fabricated for the NCERC and ATR experiments and are described within this paper.

Yarı entansif şartlarda yetiştirilen İvesi ırkı koyunlarda süt verimi ve süt kalite özellikleri

This research was carried out to determine milk yield and milk quality parameters of Awassi sheep raised under semi-intensive conditions in Harran University Experimental Animal Research and Application Center. In the study, 2 and 3 years old, 46 heads of Awassi sheep were used as animal material. The care and feeding of the ewes were made in a way that the Animal Research and Application Center routinely applied. Average daily milk yield in Awassi sheep was determined as 1002.82±52.57 g. Lactation milk yield and lactation period were calculated as 168.10±8.44 kg and 166.10±2.11 days, respectively. In the study, the overall mean fat, protein, lactose and dry matter ratios were determined. % 6.27±0.10; 5.12±0.05; 4.81±0.05 and 17.44 ± 0.13 respectively. Somatic cell count and pH values in Awassi sheep milk were determined as 207.56±21.29 cell/ml and 6.29±0.03 respectively. L*, a* and b* values in sheep milk were determined as 72.69±0.16; -6.11±0.04 and 6.92±0.08. respectively. It was determined that the amount of butyric acid (C4:0), which is one of the short-chain fatty acids, was higher than the values reported for sheep milk in all groups examined in the study. As a result, it has been determined that there is a wide variation in milk yield in Awassi sheep. A rapid genetic improvement may be achieved by utilizing this variation.

The Hypatia Experiment: Yttrium Hydride and Highly Enriched Uranium Critical Experiment

The Hypatia measurement campaign with YHx moderators and highly enriched uranium (HEU) was completed in January 2021 at the U.S. Department of Energy’s National Criticality Experiments Research Center at the Nevada National Security Site. This measurement campaign provided unique integral measurements based on two experimental configurations and investigated the temperature effects of yttrium hydride (YHX = 1.8 and 1.9) in a critical reactor system, which is of potential interest for microreactor designs. The Hypatia experiment consisted of a fuel column composed of HEU, 93 wt% 235 U discs, encapsulated YHX, aluminum oxide heater plates, and other moderator and reflector materials (beryllium, depleted uranium, and graphite) inserted into a thick beryllium reflector. During the Hypatia experiment, baseline measurements were taken at room temperature. The aluminum oxide heater plates were specially designed and used for this project to increase the central core temperature to a range of temperatures, after which additional reactivity measurements were taken. Thermal and neutronic calculations predicted that YHX is a unique material that can exhibit a positive temperature coefficient of reactivity (i.e., reactivity can increase as the temperature in the YHX increases). Reactors using YHX should account for this unique feature during design, and the results of the Hypatia experiment significantly aid that process. For configuration 1, six different temperature reactivity measurements were taken with four YHX cans in the fuel column. For configuration 2, six different temperature reactivity measurements were taken with two YHX cans in the fuel column. The use of these two configurations provide a comparison of neutronic effects from the YHX cans versus other components. Preliminary conclusions show the positive temperature coefficient is similar but slightly less than predicted by simulations. These two sets of data will be used to separate the reactivity coefficients of the fuel and other materials in the fuel column.

Biochemical and hematological profiles of wistar rats at the selcuk university experimental medicine research and application center

Biochemical and hematological profiles of wistar rats at the selcuk university experimental medicine research and application center

A New Era of Nuclear Criticality Experiments: The First 10 Years of Radiation Test Object Operations at NCERC

The work presented in this paper focuses on the first 10 years (2011–2020) of radiation test object (RTO) operations at the National Criticality Experiments Research Center. RTOs are subcritical configurations of special nuclear material that are built by hand. These configurations are utilized for benchmark experiments, detector testing/characterization, and training. An overview of the types of measurements used in RTO operations is given as well as a history of RTO operations at Los Alamos National Laboratory from 1944–2011.

A New Era of Nuclear Criticality Experiments: The First 10 Years of Planet Operations at NCERC

Planet is a vertical-lift assembly machine currently located at the National Criticality Experiments Research Center (NCERC) at the Nevada National Security Site. In the past, Planet resided at Technical Area-18 in Los Alamos, New Mexico, as part of the Los Alamos Critical Experiments Facility (LACEF). Following the de-inventorying of LACEF, the Planet assembly was relocated to NCERC in 2008 and became fully operational in June of 2011. The Class Foils experiment, which involves stacking highly enriched uranium foils to obtain a critical configuration, was the first critical experiment performed on Planet. As a major component of the Nuclear Criticality Safety Class taught for the U.S. Department of Energy (DOE) Nuclear Criticality Safety Program, the Class Foils experiment allows personnel from all over the DOE complex to handle nuclear material and to complete the approach to critical safely and successfully. This paper describes the Planet vertical assembly and recent engineering upgrade and a selection of the experiments that have been performed on Planet since its transition to NCERC 10 years ago.

A New Era of Nuclear Criticality Experiments: The First 10 Years of Godiva IV Operations at NCERC

The work presented in this paper focuses on the first 10 years (2011–2020) of Godiva IV operations at the National Criticality Experiments Research Center (NCERC). Godiva IV is a fast burst critical assembly constructed of approximately 65 kg of highly enriched uranium fuel alloyed with 1.5% molybdenum for strength. Godiva is one of the last such critical assemblies in the United States and can be used for studies of super-prompt-critical behavior as well as irradiations and demonstrations. An overview of the startup of Godiva IV at NCERC is given followed by a summary of the experiments performed utilizing Godiva IV over the first 10 years of operation at NCERC.

A New Era of Nuclear Criticality Experiments: The First 10 Years of Flattop Operations at NCERC

The Flattop critical assembly was built and operated from 1958 through 2004 at the Pajarito Site (Technical Area-18), home to the Los Alamos Critical Experiments Facility. Flattop was disassembled in 2005 and refurbished over the course of 3 years. In 2008, Flattop was installed in the National Criticality Experiments Research Center (NCERC) located in the Device Assembly Facility at the Nevada National Security Site. Startup of Flattop with a uranium core occurred in 2011. This paper details the first 10 years of Flattop operations at NCERC (2011–present).

Special issue on the National Criticality Experiments Research Center

I am honored to introduce this special issue of Nuclear Science and Engineering dedicated to and in honor of the 10th operational anniversary of the Department of Energy’s (DOE’s) and the National ...

A New Era of Nuclear Criticality Experiments: The First 10 Years of Comet Operations at NCERC

Comet is a general-purpose, heavy-duty, vertical-lift assembly designed for flexibility in conducting a variety of critical experiments. It is currently located at the National Criticality Experiments Research Center (NCERC) in Nevada. In the past, Comet resided at Technical Area-18 in Los Alamos, New Mexico, as part of the Los Alamos Critical Experiments Facility (LACEF). The Comet assembly was relocated to NCERC in 2008 and became fully operational in June of 2011. The first critical experiment performed on Comet at NCERC was a verification of one of the previous configurations of the Zeus experiment series. Over the next 10 years, many additional experiments followed including other Zeus configurations as well as completely new designs. This paper discusses the Comet vertical-lift assembly, the transition from LACEF to NCERC, and a selection of experiments that have been performed on Comet during its first 10 years of operation at NCERC.

Effect of Sirolimus on Intra-Abdominal adhesion development in a rat model

Objective: Postoperative intraabdominal adhesions still cause significant morbidity in surgical patients. This study aims to evaluate the effects of an immunosuppressor known as Sirolimus and an antiadhesive membrane which is formed with sodium hyaluronate carboxymethylcellulose-based bioresorbable membrane (Seprafilm™) to the intraabdominal adhesion formation in a rat model.
 Materials and Methods: This experimental study was performed at an experimental research center, Yeditepe University Faculty of Medicine, Istanbul. Spraque-Dawley Rats, at a weight of about 250±20 gr, were used. Group 1 (n=8): Abdomen was closed after applying cecal abrasion (control group), group 2 (n=8): 10 x 30 mm Seprafilm™ was applied under the abdominal wall after cecal abrasion ( Seprafilm™ group ). Group 3 (n =8): Sirolimus (0,5 mg/kg) was applied (Sirolimus group). Adhesions quantitatively evaluated by a blinded assessor according to the classification of Nair and his colleagues.
 Results: Statistically significant difference in terms of adhesion severity scores according to the Nair classification was found between the Sirolimus and the control group (p=0,03). Whereas, no statistically significant difference was found between the Seprafilm™ and the control group (p=0,17). Similarly, no statistically significant difference was found between Seprafilm™ and sirolimus group (p=0,64).
 Conclusion: Although there was no statistically significant difference between intraperitoneal application of Sirolimus and Seprafilm™ group (p = 0.57), a statistically significant difference was found when each group compared with the control group (p=0,03). Combined anti-adhesive effect of Sirolimus and Seprafilm™ can be evaluated in future studies.

COMPARISON BETWEEN STRONTIUM RANELATE AND METAL SUBSTITUTED HYDROXYAPATITE AS GRAFTING MATERIALS IN TREATMENT OF PERI-IMPLANT BONY DEFECTS WITH IMMEDIATE IMPLANTS (CLINICAL AND EXPERIMENTAL STUDY)

Objective:The aim of this study is to compare between both of strontium ranelate and metallic substitute of hydroxyapatite as grafting materials in the treatment of peri-implant bony defects with immediate placement of dental implant in type I extraction sites within maxillary esthetic zone among clinical and experimental levels. This assessment was based on clinical, radiographic and histological studies. Subjects and Methods: The present study was carried on two types of population among both experimental levels on experimental white albinus rabbits and on clinical level among human patients for replacement of non-restorable maxillaryanterior and/or premolar teeth within esthetic zone by immediate implant. A written informed consent was obtained from all patients before their participation in this study.Patients were classified into two groups: the first one was with five patients with non-restorable maxillary anterior or premolar tooth that was treated by an immediately placed implant in conjunction with metallic substituted hydroxyapatite while the second one was treated by an immediately placed implant in conjunction with strontium ranelate as grafting material.The second sample population of study was carried out among ten male white (newzland) experimental rabbits with average body weight between 2.5 and 3 KG and within suitable environmental conditions in Medical Experimental Research Center (MERC) in faculty of medicine, Mansoura University. All rabbits sample was also divided equally and randomly in two groups with five rabbits within each one by the same criteria as mentioned where the first group was composed of five rabbits that received dental implant within intentionally made defect in tibia by trephine bur in conjunction with metallic substituted hydroxyl apatite as grafting material within gap between implant and defect and the second group was with the same criteria and procedures with strontium ranelategafting material within the defect. Pre-oparative photographs and cone beam computed topography (CBCT) were taken for study sample population. Within clinical patients, immediately paced dental implant have been placed in anterior esthetic zone with bone grafting around dental implant according to each group, Immediate CBCT and implant stability measurements has been taken after surgery followed by six months follow-up period to evaluate marginal bone loss, bone density, papillary esthetic score, implant stability and probing depth around dental implants. While within experimental animals trephine bur was used to intentionally create the bony defect that will simulate defect around immediate dental implant with grafting material around according to each group with six months follow-up to evaluate marginal bone loss, implant stability,bone density and for histological examination around implant within grafted area. All data were collected and statistically analyzed. Results:Generally among both clinical and experimental levels within both of clinical patients and experimental rabbits, metal substituted hydroxyl apatite (MSHAP) showed better results with significant difference than that presented in other group that has received Strontium ranelate (Sr) as a grafting material to fill the bony marginal gap around immediate dental implant during six months follow-up study period. Results presented high difference of significance between two groups in experimental and clinical levels in concern with both implant stability, marginal bone loss and even in bone quality and denisty when measured after six months follow-up. On the other hand there was no significant difference in concern with soft tissue response after six months in relation with peri-implant probing depth and MSHAP showed slight better results than that of Sr in records of papillary esthetic scores among clinical patients. Histological results showed better response of surrounding bony tissues towards MSHAP than that of Sr with more affinity of osteoblasts and osteocytes to the site of the grafted area. Conclusions:Metallic substituted hydroxyl-apatite (MSHAP) with its additive magnetic molecules within hydroxyapatite structure has better bony response from surrounding bony tissues than that provided by Strontium Ranelate (Sr) according to bone filling and preservation with less marginal loss, more affinity of new osteoblasts and mature osteocytes, long term implant stability after grafting and better bone density and quality at the grafted area around immediate dental implants in anterior maxillary area.

Moderate Aerobic Exercise May Reduce Metabolic Syndrome Induced Testicular Oxidative Stress and Deterioration in Sperm Parameters

Aims: Studies on testicular oxidative stress, sperm density, motility and morphology of exercise applications in the case of metabolic syndrome is limited. In the present study, it was aimed to investigate the effects of aerobic and anaerobic exercise applications on sperm parameters and testicular oxidative stress parameters in metabolic syndrome induced rats.
 Study Design: Controlled Trial.
 Place and Duration of Study: Firat University Experimental Research Center, Elazığ/Turkey.
 Methodology: A total of 24 male Wistar-Albino rats were used in the study. For inducing the metabolic syndrome, 30% fructose solution was prepared fresh every day and administered ad-libitum through the drinking water of the animals. The rats were divided into 4 groups (G1: Control, G2: Metabolic Syndrome, G3: Metabolic Syndrome + Aerobic Ex., G4: Metabolic Syndrome + Anaerobic Ex.). Exercise practices continued 3 days in a week for 6 weeks.
 Results: Sperm concentrations of G2 and G4 were statistically significantly lower than the control group. The abnormality percentage of G4 was statistically significantly higher than the other groups in terms of head abnormality and total abnormality. MDA level of G2 was statistically significantly higher than the other groups, while GSHpx and catalase levels were low.
 Conclusion: It can be said that metabolic syndrome may cause oxidative damage in testicular tissue and deterioration in sperm parameters. Moderate-intensity aerobic exercise reduces the deterioration in sperm parameters by creating a protective response against oxidative damage.

Isolation of Scopulariopsis brevicaulis from Wistar Rats

Scopulariopsis brevicaulis is a saprophytic fungus that has wide geographic distribution. This study describes a case of hair loss and skin lesions observed in male and female Wistar rats due to Scopulariopsis brevicaulis infection in Turkey. Skin scrapings and hair samples from three male and two female rats were provided by the Experimental Animal Production and Experimental Research Center of Mehmet Akif Ersoy University to the Faculty of Veterinary Medicine, Department of Microbiology Laboratory in Burdur for analysis in July 2019. Microbiological methods were used for species identification and Scopulariopsis brevicaulis was isolated from all of the samples. The rats completely recovered without treatment and had no recurrence of clinical signs at one month post-sampling. This study is the first report of S. brevicaulis causing an infection in Wistar rats in Turkey.

The Effect of Feeding with Resveratrol on Myogenin and mTOR Levels in Mice

Aim: It is reported that resveratrol may induce muscle hypertrophy and myogenesis. Accordingly, resveratrol is promising for the treatment of muscle diseases and ergogenic aid for athletes. In this study it is aimed to observe the effects of resveratrol on myogenin and mTOR levels and muscle mass.
 Material and Methods: The study is performed on 14 Swiss albino young adult mice at Başkent University Experimental Animal Research Center. The mice are divided randomly into study (n:7) and control (n:7) groups. During consecutive 7 days, 20 mg/kg trans-resveratrol was given to the study group intraperitoneally. After the seventh day administration, the right gastrocnemius muscles are disected, weighted and stored at -80 °C for mTOR and myogenin analysis. Then, myogenin and mTOR levels are determined by enzyme-linked immunosorbent assay (ELISA) method in homogenised muscle mass.
 Results: According to mean myogenin and mTOR levels, there was no significantly difference between groups (p>0.05). Total body weight and the right gastrocnemius muscle weight of the study group (22.11±3.22 g, 0.09±0.03 g, respectively) at the 7th day was found significantly lower than control group (28.63±3.80 g, 0.12±0.02 g, respectively) (p<0.05).
 Conclusion: It was observed that resveratrol administration had no effect on myogenin and mTOR levels which is a fore-step for muscle hypertrophy. On the other hand, interestingly total body weight and muscle mass decrease was observed in the study group. The effects of resveratrol on muscle tissue is a relatively less studied topic. However, the authors are suggesting more studies on the resveratrol usage or administration for the effective dose and time interval investigation.