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Determination of the Earth’s gravity field and geopotential value is one of the fundamental topics in physical geodesy. Traditional terrestrial gravity and precise leveling measurements can be used to determine the geopotential values at a local or regional scale. However, recent developments in optical atomic clocks have not only rapidly improved fundamental science but also contributed to applied research. The latest generation of optical clocks is approaching the accuracy level of 10−18 when facilitating atomic clock networks. These systems allow examining fundamental theories and many research applications, such as atomic clocks applications in relativistic geodesy, to precisely determine the Earth’s gravity field parameters (e.g., geopotential values). According to the theory of relativistic geodesy, the frequency difference measured by an optical clock network is related to the gravity potential anomaly, provided that the effects of disturbing signals (i.e., tidal and non-tidal contributions) are filtered out. The relativistic geodesy principle could be used for a practical realization of global geodetic infrastructure, most importantly, a vertical datum unification or realization of height systems. This paper aims to review the background of relativistic (clock-based) geodesy and study the variations of optical atomic clock measurements (e.g., due to hydrology loading and land motion).

One of the main factors that cause the devil to interfere in human thoughts and actions and affect it is exaggeration in religion. One of the most important threats to religion in every day is misconceptions in this area. One of the most important religious misconceptions is exaggerated beliefs and thoughts. These beliefs can have adverse consequences in various areas related to religion, including a kind of baseless conflict between religion and reason or religion and science that arises from some exaggerated beliefs. In Islam, the middle of the first century AH, ie the period of the caliphate of Imam Ali (as), is the origin of the emergence of exaggerated ideas or excesses in religious beliefs among Muslims. Not only did these beliefs not disappear in the following centuries, but they continued on their way, openly and secretly, until in the time of Sadeghin (AS), they became currents that systematically tried to fabricate hadith and promote beliefs. In the present study, by passing an exaggeration from the point of view of the Imams and the books of the Ahl al-Bayt, which sometimes causes methods such as examining the document and trusting the famous sayings and books in recognizing them, are ineffective. Then, by examining and analyzing examples of important hadiths that have been a refuge for exaggerated thoughts so far, the method of discovering exaggerated beliefs, relying on the method that has been emphasized by the Imams (AS), reveals the explanation and rejection of these ideas.

Introduction The lenticular Shahneshin barite deposit (N: 35°39'36'' and E: 46°36'11'') is located 80 km northeast of Marivan, Kurdistan Province; north Sanandaj-Sirjan Zone (Stöcklin, 1968). The deposit consists of stratiform ore and stringer zone. The stringer zone has occurred with alteration sericite- quartz in the footwall dacitic unit (Kv) and evident in a series of vein-veinlets under stratiform ore. The stratiform ore has been located concurrently on the dacite unit and below the Sanandaj Shale unit (Hasankhanloo, 2015). The study area mainly consists of Mesozoic succession dominated by the dacite tuff, andesitic-basaltic lava and pillow lava (Kv: the host rock), black slate and phyllite (Kss: Sanandaj Shale), dolomitic limestone with intercalation of sandstone (Kl), and black shale and slate (Ks: Sanandaj Shale). In this study, samples of the Shahneshin barite deposit have been analyzed for their 87Sr/86Sr and δ34S isotopes and trace elements (plus REE) geochemistry to assess the source of the deposit. Materials and methods Forty samples were collected from the Shahneshin barite deposit and country rocks. Polished blocks (6 samples) and thin sections (34 samples) were prepared for SEM images and petrographic examination at the University of Kurdistan. Trace elements (plus REE) were determined by ICP-MS in the Geological Survey center of Iran (Karaj). The detection limits for elements are between 0.08-0.6 ppm. Three whole-rock samples for Sr and S isotopes were analyzed at the Department of Earth and Space Sciences of the University of Science and Technology of China. Sulfur isotope analyses were measured by the use of a Delta V Plus Gas Isotope Ratio Mass Spectrometer. The analysis accuracy was determined to be ±0.2‰ (2σ) by using Canyon Diablo Troilite (CDT) as a standard (34S/32S=0.0450045). The strontium isotopic composition was completed on a Thermal Ionization Mass Spectrometry instrument by Phoenix. The measured strontium isotope normalized to 86Sr/88Sr=0.1194 and its NBS-987 standard was 0.7102477±0.000014 (2σ). Results Strontium isotopes, sulfur isotopes, trace-element (plus REE) composition, fluid inclusion, and petrography of barites help to identify sources of mineral-forming components and environments of precipitation (Baioumy, 2015). The Shahneshin barite deposit includes sulfate barium without valuable Pb and Zn elements. Barite crystals are mainly coarse (>20µ m) with euhedral, tabular, and bladed morphologies. Fluid inclusion microthermometry indicates that the barite formed from low salinity (2.0-8.5 wt.% NaCl eq.) fluids at low temperatures, between 115 to 215oC (Hasankhanloo, 2015). Chondrite-normalized REE patterns for the barite samples reflect enrichment of the LREE/HREE ratios, as is shown by the high (Nd/Er)CN> 11 ratios. They also show Eu/Eu*CN (0.5-7.0), Ce/Ce*SN (0.1-1.16), La/Lu*CN >1, and ratios of the Ce/La (mostly>1), and Eu/Sm (0.1-2.83). The geochemistry of the barite samples represents variation in the abundance of trace elements and REECN patterns. The 87Sr/86Sr and S-isotopic values of Shahneshin barite samples are 0.70649-0.70651 and δ34S=19.05-21.53‰, respectively. Discussion Barite has very little Rb in its structure, and the isotopic composition of the original Sr is preserved in it (Martin et al., 1995). The 87Sr/86Sr values of the barite samples are consistent with 87Sr/86Sr=0.70649-0.70651, which itself is higher than those for host volcanic rocks (0.704-0.705) but lower than that of the Cretaceous seawater (0.7075), the time of barites formation. We may conclude that strontium in the barites is a mixture of predominantly juvenile hydrothermal fluid of low Sr isotope and seawater that contains more radiogenic strontium. δ34S (=19.05-21.53‰) of the samples indicate that much of the sulfur in barite was derived from seawater (δ34S=20-22‰). Fluid inclusion salinities (Hasankhanloo, 2015), crystal sizes and morphology, abundance of sulfate mineral, lack of valuable Pb and Zn, distribution patterns of trace elements (plus REE) of barite reveal that mixture of magmatic fluid and seawater, with different ratios, were the source of the barite-forming fluid. That is supported by the δ34S values, the location of samples on the Th-U diagram (seawater sources), variations in trace element (plus REEs), and Au anomaly (magmatic sources) in the samples. REEs, La enrichment, variations in abundance of trace elements, as well as δ34S and 87Sr/86Sr isotope values of the samples are consistent with the Kuroko massive sulfide-type (Marumo, 1989) and submarine hydrothermal volcanic model. In this model, barium has leached from the bedrocks by circulation of reduced hydrothermal fluid and transported along the syn-sedimentary normal faults to the sea-floor. Then, fluid is mixed with SO42- of seawater and it causes the barite to precipitate. These barites have been formed in an open system, on or immediately below the sea-floor. The Shahneshin barite deposit was, most probably, formed within caldera structures on top of the volcanic complexes in the late-stage of submarine volcanic activity with andesite-dacite in composition. It has occurred at continental margin tectonic setting between subduction zone and passive continental margin due to oblique collision along the Sanandaj-Sirjan Zone in the Late Cretaceous.

Employing 3D printing bone scaffolds with various polymers is growing due to their biocompatibility, biodegradability, and good mechanical properties. However, their biological properties need modification to have fewer difficulties in clinical experiments. Herein, the fused‐deposition modeling technique is used to design triply‐periodic‐minimal‐surfaces polylactic‐acid scaffolds and evaluate their biological response under static and dynamic cell culture conditions. To enhance the biological response of 3D‐printed bone scaffolds, graphene‐oxide (GO) is coated on the surface of the scaffolds. Fourier‐transform infrared spectroscopy, X‐ray diffraction, and energy‐dispersion X‐ray analysis are conducted to check the GO presence and its effects. Also, computational fluid dynamics analysis is implemented to investigate the shear stress on the scaffold, which is a critical parameter for cell proliferation under dynamic cell culture conditions. Compression tests and contact‐angle measurements are performed to assess the GO effect on mechanical properties and wettability, respectively. Also, it was shown that surface‐treated scaffolds have lower mechanical properties and higher wettability than uncoated scaffolds. A perfusion bioreactor is used to study cell culture. Also, field‐emission‐scanning‐electron‐microscope and 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5 diphenyl‐tetrazolium‐bromide (MTT) assay analyses are conducted to observe cell viability and cell attachment. An increase of up to 220% in viability was achieved with GO and dynamic cell culture. [ABSTRACT FROM AUTHOR]

In a qualitative and descriptive-analytical manner, this paper seeks to achieve Islam’s view about the priority of the encouragement or punishment approaches in education, and to provide Quranic methods for applying the Quran’s view and its application in the official and public education of the country, in order to facilitate the educational process and to increase the effectiveness of the educational and developmental teachings. The analytical corpus includes the text of the Quran, and the analytical sample includes all the verses that have both words of annunciation and admonition together. Data analysis was carried out simultaneously and continuously along with the process of data collection, categorization, classification, encoding, explanation, and interpretation. The findings indicate that the Holy Quran has prioritized encouragement by prioritizing annunciation. To explain and analyze how this aim is achieved, this paper deals with the expression of the mind-tospeech connection, purposefulness of speech, the application of prioritization and postponement in the accurate interpretations of the Quran verses, Imams’ use of Quranic prioritization and postponement for the precise determination of the Islamic priorities as the authoritative basis of Quranic prioritization and postponement, and the prioritization of annunciation over admonition in the Holy Quran. Similarly, the (verbal, material, emotional, and value-based) encouragement methods extracted from the Quranic text are: admiration, expressing satisfaction, praying, persuasion, expressing good deeds, saluting, and promising as verbal methods; affection and dignity as emotional methods; and taking into account the individual’s special status, and expressing satisfaction as the value-based methods.

Enjoyment of the rewards of preserving (or memorizing) forty hadiths for the nation, which has been mentioned in the Prophetic narratives, has led to a type of hadith writings called 'Arba'een writings. This style among Shiites and Sunnis, since the first 'Arba'een has compiled in the second century AH until the writings in the present day, has passed its evolution in two different tracks; these writings can be divided in two types of thematic and documentary (sanad) 'Arba'een writings. This study investigated interactions between Shi'as and Sunnis in periods of ups and downs of Arba'een writing to achieve the status of a style of an evolved tradition writing. It shows that Sunnis firstly commenced compiling 'Arba'een books and before Shi'as they evolved its thematic and documentary types. It has begun by Shi'as through compiling virtues and usually continued in thematic type. In contemporary, the interest has been reduced among Sunnis, but Shiite authors have considered it continuously.

In this article, the transverse vibrations of bi-directional functionally graded (FG) nanobeams subjected to a longitudinal magnetic field are investigated. The nonlocal elasticity theory is exploited to consider the small-scale effect. Material properties of FG nanobeam are assumed to vary continuously along the thickness and length with arbitrary function. The equations of motion and boundary conditions are obtained using Hamilton's principle. These equations are solved by employing the generalized differential quadrature method. The effect of different parameters such as bi-directional FG parameters, size-dependent parameter, and value of the magnetic field on vibration are investigated. It is concluded that different factors as notated, play significant roles in the vibrational response of bi-directional FG nanobeams, and by using the magnetic field, the vibration frequencies of nanostructures can be controlled. Communicated by Jie Yang. [ABSTRACT FROM AUTHOR]

This article presented a solution for torsion vibration a nanotube made of pores material. Based on the porosity distribution, the material properties are assumed to vary according to a function along radius of nanotube. Moreover, the cross-section area of nanotube varied in the longitudinal direction by nonlinear function. As for the torque effect of the axial magnetic field, the well-known Maxwell's relation is used. Couple stress theory is employed to study the influence of small-scale on torsional vibration of nanotube. The Navier equation and boundary conditions of the size-dependent porous nanotube were derived by the Hamilton principle. These equations were solved by employing the generalized differential quadrature method. Comparison between the results of the present work with the other paper reveals the accuracy of this study. To the best of authors' knowledge, so far all previous torsional vibration of nanotube address the case of ignoring porosity. The novelty of this work is to present a solution by taking into account the existence of porosity. Finally, numerical results are presented to study the small scale effect and porosity on the frequency of the porous nanotube. [ABSTRACT FROM AUTHOR]