Design and characterization of multi-spectral underwater beam-port for pool-type research reactors

“The beam-port is a cardinal facility at research reactors necessary for dry irradiation, testing and measurement experiments. The Missouri University of Science and Technology Reactor (MSTR) is one such reactor with a beam-port. Installation of additional beam-port in such reactor facilities can be prohibitive. A novel remedy to this is an underwater beam-port for pool-type reactors. The design and characterization of a conceptual underwater multi-spectral beam-port for neutron and gamma fluxes were completed for the MSTR. The neutron spectra from the MSTR were simulated using the Monte Carlo N-particle (MCNP). The determined neutron spectra were experimentally validated using SAND-II. The underwater beam-port system was designed to be portable so that it could be moved in and out of the reactor pool. Filters and collimators were used to modify the neutron beams for thermal and fast neutron densities as well as gamma energy spectra at the target location. In its most thermal neutron configuration, the beam-port delivered 1.43 × 109 n cm-2 s-1 to the target with 91.7% of the flux having energies no greater than 0.55 eV. The hardest spectrum achievable in its fast neutron configuration was 4.95 × 109 n cm-2 s-1 with 51.8% of the flux having energies greater than 0.1 MeV. The beam-port was able to deliver gamma flux of 3.19×1010 photons/cm2s to the target. A predictive algorithm was developed in MATLAB so that: 1.) beam flux quality could be determined given collimator and filter dimensions and 2.) Collimator and filter dimension could be determined given desired flux qualities. For both scenarios, the maximum prediction errors were 19% and 8.5%, respectively. The algorithm reduced time required for one simulation to 0.007 seconds from 179 minutes when using MCNP --Abstract, page iii

Topological distances and geometry over the symmetrized Omega algebra

[EN] The aim of this paper is to study some topological distances properties, semidendrites and convexity on th symmetrized omega algebra. Furthermore, some properties and exponents on the symmetrized omega algebra are introduced.Alqahtani, M.; Özel, C.; Zekraoui, H. (2020). Topological distances and geometry over the symmetrized Omega algebra. Applied General Topology. 21(2):247-264. https://doi.org/10.4995/agt.2020.13049OJS247264212A. C. F. Bueno, On the exponential function of right circulant matrices, International Journal of Mathematics and Scientific Computing 3, no. 2 (2013).L. Hörmander, Notions of convexity, Progress in Mathematics 127, Birkh¨auser, Boston- Basel-Berlin (1994).S. Khalid Nauman, C. Ozel and H. Zekraoui, Abstract Omega algebra that subsumes min and max plus algebras, Turkish Journal of Mathematics and Computer Science 11 (2019) 1-10.G. L. Litvinov, The Maslov dequantization, idempotent and tropical mathematics: a brief introduction, Journal of Mathematical Sciences 140, no. 3 (2007), 426-444. https://doi.org/10.1007/s10958-007-0450-5D. Maclagan and B. Sturmfels, Introduction to Tropical Geometry, Graduate Studies in Mathematics, vol. 161, American Mathematical Society, 2015. https://doi.org/10.1090/gsm/161C. Ozel, A. Piekosz, E. Wajch and H. Zekraoui, The minimizing vector theorem in symmetrized max-plus algebra, Journal of Convex Analysis 26, no. 2 (2019), 661-686.J.-E. Pin, Tropical semirings, Idempotency (Bristol, 1994), 50-69, Publ. Newton Inst., vol. 11, Cambridge Univ. Press, Cambridge, 1998. https://doi.org/10.1017/CBO9780511662508.004I. Simon, Recognizable sets with multiplicities in the tropical semiring, in: Mathematical Foundations of Computer Science (Carlsbad, 1988), Lecture Notes in Computer Science, vol. 324, Springer, Berlin, 1988, pp. 107-120. https://doi.org/10.1007/BFb001713

Soft nodec spaces

Following van Douwen, we call a soft topological space soft nodec if every soft nowhere dense subset of it is soft closed. This paper considers soft nodec spaces, which contain soft submaximal and soft door spaces. We investigate the basic properties and characterizations of soft nodec spaces. More precisely, we show that a soft nodec space can be written as a union of two disjoint soft closed soft dense (or soft open) soft nodec subspaces. Then, we study the behavior of soft nodec spaces under various operations, including the following: taking soft subspaces, soft products, soft topological sums, and images under specific soft functions with the support of appropriate counterexamples. Additionally, we show that the Krull dimension of a soft nodec soft $T_{0}$-space is less than or equal to one. After that, we present some connections among soft nodec, soft strong nodec, and soft compact spaces. Finally, we successfully determine a condition under which the soft one-point compactification of a soft space is soft nodec if and only if the soft space is soft strong nodec

New Topology on Symmetrized Omega Algebra

The purpose of this paper is to define a new topology called symmetrized omega algebra topology and discuss some of its topological properties. Two different examples from an ordered infinite set of symmetrized omega topology are introduced. Furthermore, we study the relationship between symmetrized omega topology and weaker kinds of normality

Online project-based learning for ESP: Determinants of learning outcomes during Covid-19

Evaluating the learning outcomes of a certain course implementation can improve the quality of education. This study is focused on Indonesian EFL undergraduates’ perceptions of the relationships between teacher performance, technological resources, online project-based learning (OPJBL), and ESP learning outcomes. Participants of the study have attended English for specific purposes (ESP) online courses during school closures due to Covid-19. A survey was addressed to 350 undergraduates after a one-semester implementation of the OPJBL. The students were requested to rate their perceptions on validated items using a 7-point Likert-type scale for the data collection. The data were modelled and computed through partial least square structural equation modelling (PLS-SEM). The main findings of the study revealed that teacher performance and technological resources were significant in predicting OPJBL. Similarly, OPJBL was found to play a significant role in affecting ESP learning outcomes. Teacher performance and technological resources were also correlated to ESP learning outcomes. Significant differences were found among students’ locations for all variables. The findings highlight the benefits of the SEM approach for establishing the proposed framework and assessing the links between variables concerning the OPJBL and learning outcomes

Unlocking English proficiency: Youtube's impact on speaking skills among indonesian university students

This study examines the factors affecting the intention to use and actual use of YouTube in improving English-speaking skills in Indonesia. To meet the aims, we extended the theory of technology acceptance model (TAM); two external factors, subjective norms, and perceived enjoyment, to support the TAM variables (perceived ease of use, perceived usefulness, attitude, intention to use, and actual use). Data were collected through a survey with 526 measurable responses from Indonesian preservice English teachers in three Indonesian universities. The data were analyzed through partial least square structural equation modeling (PLS-SEM), measurement, and structural model. The findings informed that all hypothesized relationships were accepted and confirmed. The strongest relationship emerged between intention to use and actual use. Meanwhile, the weakest correlation was between subjective norms and perceived ease of use. The study facilitates recommendations for future researchers, language educators, and all related parties

First evidence for human occupation of a lava tube in Arabia: The archaeology of Umm Jirsan Cave and its surroundings, northern Saudi Arabia

Recent advances in interdisciplinary archaeological research in Arabia have focused on the evolution and historical development of regional human populations as well as the diverse patterns of cultural change, migration, and adaptations to environmental fluctuations. Obtaining a comprehensive understanding of cultural developments such as the emergence and lifeways of Neolithic groups has been hindered by the limited preservation of stratified archaeological assemblages and organic remains, a common challenge in arid environments. Underground settings like caves and lava tubes, which are prevalent in Arabia but which have seen limited scientific exploration, offer promising opportunities for addressing these issues. Here, we report on an archaeological excavation and a related survey at and around Umm Jirsan lava tube in the Harrat Khaybar, north-western Saudi Arabia. Our results reveal repeated phases of human occupation of the site ranging from at least the Neolithic through to the Chalcolithic/Bronze Age. Pastoralist use of the lava tube and surrounding landscape is attested in rock art and faunal records, suggesting that Umm Jirsan was situated along a pastoral route linking key oases. Isotopic data indicates that herbivores primarily grazed on wild grasses and shrubs rather than being provided with fodder, while humans had a diet consistently high in protein but with increasing consumption of C3 plants through-time, perhaps related to the emergence of oasis agriculture. While underground and naturally sheltered localities are globally prominent in archaeology and Quaternary science, our work represents the first such combined records for Saudi Arabia and highlight the potential for interdisciplinary studies in caves and lava tubes

Prevalence of Bipolar Disorder and Associated Risk Factors Among Population in Western Region Of Saudi Arabia: A Cross-Sectional Study

Objective: To determine the prevalence of bipolar disorder and associated risk factors among the population in the Western Region, KSA. Methods:This research will employ a cross-sectional study design. Cross-sectional studies are well-suited for assessing the prevalence and risk factors of a particular condition in a specific population at a single point in time. This design will allow us to gather data on the prevalence of bipolar disorder and identify associated risk factors among the population in the Western region of Saudi Arabia. Results: The study included 407 participants. The most frequent weight among them was 51-65 kg (n= 109, 26.8%), followed by 66-75 kg (n= 93, 22.9%). The most frequent height among study participants was 1.61-1.70 m (n= 137, 33.7%) followed by 1.51-1.60 m (n= 128, 31.4%). The most frequent body mass index value was 18.5-24.9 kg/m2 (n= 161, 39.6%), followed by 25-29.9 kg/m2 (n= 142, 34.9%). The gender of study participants is almost equal with male (n= 204, 50.1%) and female (n= 203, 49.9%). The most frequent age among them was 62 years and above (n= 157, 38.6%), followed by 40-50 years (n= 92, 22.6%). Participants were asked the participants about what is the duration of their mental illness(bipolar). The most frequent answer was nothing (n=277,68.1%), followed by one year (n=96, 23.6%), and the least of them were six years (n=1,0.2%). Conclusion: The results showed that most of the study participants are married and intermediate owners and most of them have a university education. Most participants are not overweight according to their body's bodies. Most of the study participants had a good social link

Potential bioactivity of Phoenix dactylifera fruits, leaves, and seeds against prostate and pancreatic cancer cells

The use of functional foods’ phytochemicals in the chemoprevention of different cancer diseases has become one of the hot scientific areas in the clinical nutrition field. For instance, the Khalas palm cultivar (KPC; Phoenix dactylifera) is one of the natural sustainable resources that have high bioactivity and functionality. This study aimed to investigate the antiproliferative activity and mode of action of KPC’s different parts on prostate (Pc3) and pancreatic (panc1) cancer cells at a molecular level. In the methods, KPC’s leaves, seeds, and fruits’ chemical composition and phytochemical analysis were analyzed. Also, the cytotoxic effects of each extract were assessed against pc3 and panc1 cell lines. Besides, induction of apoptosis, cell cycle analysis, and gene expression of both Cap3 and Cap9 were studied. The obtained results indicated that KPC leaves extract exhibited the highest significant (P < 0.01) anti-proliferation activity against the utilized cancer cell lines compared to fruits and seeds extracts. Also, there were significant (P < 0.05) differences in the phenolic contents, flavonoid of compounds, and antioxidant power of the leaves when compared to the seeds and fruits. Additionally, the highest cytotoxic effect (lowest IC50) was recorded with leave extract than seeds and fruits. Meanwhile, the seeds extract induced (P < 0.05) the apoptosis and arrested cells in the G2/M phase as well as up-regulated the gene expression of the apoptotic-related genes (Casp3 and Casp9) compared to the control group. In conclusion, this study showed that the presence of bioactive components in the KPC different parts extracts have the significant ability to induce the apoptotic pathway that could down-regulate the proliferation of prostate (pc3) and pancreatic (panc1) cancer cells. The pathway mechanism of action was induced by the phytol molecule presented in its leaves extract

Optimising Imaging Protocols for Whole-Body SPECT/CT

Aim: This thesis investigates the application of whole-body single photon emission computed tomography/computed tomography (WB-SPECT/CT) imaging in clinical practice. Method: The first study was a systematic review and meta-analysis of 11 studies to examine the diagnostic performance of WB-SPECT/CT in detecting bone metastasis and its added value compared to planar bone scintigraphy (PBS). The second study optimised the acquisition and reconstruction parameters to preserve image quality while reducing acquisition time by utilising a phantom and clinical example. In the third study, 5 patients recruited to evaluate the clinical image quality, noise, and diagnostic confidence for various acquisition durations and iterative reconstructions. In the fourth study, 11 participants referred for bone scintigraphy using PBS and SPECT/CT to investigate the feasibility of reprojected fast WB SPECT/CT images in clinical practice. Results: The first study showed that WB-SPECT/CT performed better than PBS. The second study revealed that as the number of iterations increased, there was a corresponding improvement in overall contrast recovery, but it also increased noise levels. Additionally, the two smallest spheres (13 and 10 mm) were invisible at 3 s/view as they did not conform to the Rose criterion of Contrast to noise ratio> 5. The final study showed that the data acquired for 480 s and 450 s corresponded to ratings of good image quality, average noise and fair confidence, with no statistically significant difference between the two acquisition times. Conclusion: Rapid scanning approaching 450 seconds per bed position is feasible for WB bone SPECT/CT to provide an optimal balance between acquisition time and image quality. Furthermore, R-PBS derived from fast WB bone SPECT/CT data may be a viable alternative to PBS. Moreover, a reduced acquisition time for SPECT/CT imaging increases the potential of WB-SPECT to be adopted in a broader range of clinical applications