Undiscovered Elements Research Articles

Understanding the Mechanisms of Earth Fissuring for Hazard Mitigation in Najran, Saudi Arabia

Being a fast-growing city with a high rate of urbanization and agricultural development, the city of Najran, situated in the southwest of the Kingdom of Saudi Arabia, has witnessed a series of earth fissuring events and some other geo-environmental hazards in recent times. These fissures have posed a significant threat to inhabitants and infrastructure in the area. A few studies suggest that excessive groundwater withdrawal is responsible for fissuring activities. Because of the intensity of this geo-hazard, this article presupposes that groundwater extraction alone cannot be responsible for the magnitude of fissuring activity in the area and discusses other severe factors that could be responsible for the earth fissures. The study proposes that the cause of the problem is multifaceted and synergistic, and outlines threatening factors that can inherently trigger more fissures in the region, based on the geologic history of the area and a critical review of investigative studies conducted in the area and beyond. Predicated on the region’s structural history, some undiscovered elements that can potentially cause fissuring in the region were identified and discussed. Some of these include the pre-existence of a fault system, a crack from the bedrock ridge, the existence of paleochannels, the collapsibility of loess, the tectonic (earthquake) history of the area, and differential compaction due to heterogeneity. The use of a metaheuristic and a combined application integrating other optimization algorithms can be utilized to determine optimum hyperparameters and present their statistical importance, thereby improving accuracy and dependability in fissure prediction in Najran. Reliable models would primarily be used to monitor active fissures and identify key factors utilizing spatial information, subsidence, groundwater-related data sets, etc.

Elements of Heroism

Abstract In today’s periodic table, 118 elements stand side by side, neatly arranged in rows and columns, mapping out their relative size, proudly sharing their family’s traits, and showcasing their relative reactivity and predicted behaviour in different situations. Back in 1869 when Dmitri Mendeleev devised the arrangement of elements we use to this day, there were notable gaps left for elements that had not yet been discovered. As the arrangement of the elements was based on a range of physical and chemical properties, it was easy to predict some of the properties of the missing elements. It was in these gaps that both scientists and artists alike dared to dream about elemental discoveries with both predicted and unpredicted properties. Comic book and science fiction writers in particular had fun postulating some of the possible elements that would give their superheroes the characteristics they required to carry out their tasks. They created fictional elements in place of some of the as yet undiscovered elements, many of which now share properties with elements that exist today.

The role of tonic glycinergic conductance in cerebellar granule cell signalling and the effect of gain-of-function mutation.

A T258F mutation of the glycine receptor increases the receptor affinity to endogenous agonists, modifies single-channel conductance and shapes response decay kinetics. Glycine receptors of cerebellar granule cells play their functional role not continuously, but when the granule cell layer starts receiving a high amount of excitatory inputs. Despite their relative scarcity, tonically active glycine receptors of cerebellar granule cells make a significant impact on action potential generation and inter-neuronal crosstalk, and modulate synaptic plasticity in neural networks; extracellular glycine increases probability of postsynaptic response occurrence acting at NMDA receptors and decreases this probability acting at glycine receptors. Tonic conductance through glycine receptors of cerebellar granule cells is a yet undiscovered element of the biphasic mechanism that regulates processing of sensory inputs in the cerebellum. A T258F point mutation disrupts this biphasic mechanism, thus illustrating the possible role of the gain-of-function mutations of the glycine receptor in development of neural pathologies. Functional glycine receptors (GlyRs) have been repeatedly detected in cerebellar granule cells (CGCs), where they deliver exclusively tonic inhibitory signals. The functional role of this signalling, however, remains unclear. Apart from that, there is accumulating evidence of the important role of GlyRs in cerebellar structures in development of neural pathologies such as hyperekplexia, which can be triggered by GlyR gain-of-function mutations. In this research we initially tested functional properties of GlyRs, carrying the yet understudied T258F gain-of-function mutation, and found that this mutation makes significant modifications in GlyR response to endogenous agonists. Next, we clarified the role of tonic GlyR conductance in neuronal signalling generated by single CGCs and by neural networks in cell cultures and in living cerebellar tissue of C57Bl-6J mice. We found that GlyRs of CGCs deliver a significant amount of tonic inhibition not continuously, but when the cerebellar granule layer starts receiving substantial excitatory input. Under these conditions tonically active GlyRs become a part of neural signalling machinery allowing generation of action potential (AP) bursts of limited length in response to sensory-evoked signals. GlyRs of CGCs support a biphasic modulatory mechanism which enhances AP firing when excitatory input intensity is low, but suppresses it when excitatory input rises to a certain critical level. This enables one of the key functions of the CGC layer: formation of sensory representations and their translation into motor output. Finally, we have demonstrated that the T258F mutation in CGC GlyRs modifies single-cell and neural network signalling, and breaks a biphasic modulation of the AP-generating machinery.

The Expansion of the Periodic Table to Its Natural Limits.

One hundred and fifty years after its conception the periodic table of the elements contains 118 members with the 7th period being completely filled. This raises the question of what are the natural limits of the periodic table and whether yet undiscovered elements can be synthesized. Nowadays the alchemists' dream of producing new elements from already known ones has become reality. However, only single, short-lived atoms can be produced and investigated. The current article will give insights into the state of the art concerning the synthesis and chemical investigation of heavy and superheavy elements and discuss limits to the further expansion of the periodic table to even heavier elements in the 8th period.

Setting the table.

![Figure][1] Theodore Gray's literal periodic table of elements PHOTO: MIKE WALKER The United Nations has designated 2019 as the International Year of the Periodic Table of the Chemical Elements ([www.iypt2019.org][2]) and, with it, the 100th anniversary of the founding of the International Union of Pure and Applied Chemistry. The organizing committee declared that “The Periodic Table of Chemical Elements is one of the most significant achievements in science, capturing the essence not only of chemistry, but also of physics and biology.” Indeed, many nonscientists recognize the periodic table simply by the distinctive shape of its border, but within this border lie many aspects of science beyond chemistry. Science is about the interplay of experimental results and theory. A sufficient number of elements needed to be discovered and their properties and reactivity understood before systematic trends could be inferred. Science is also fundamentally about making testable predictions. Part of the success of Dmitri Mendeleev's original table published in 1869 was that he left gaps for the placement of undiscovered elements. Mendeleev predicted some properties of these elements, setting off a chain of scientific testing of hypotheses. The structure of the periodic table was later understood to arise from quantum mechanics. The elements themselves are produced by a complex chain of stellar nucleosynthesis processes, and the frontier of the periodic table—the search for stable superheavy elements—tests the limits of experimental atomic physics. A large periodic table is frequently displayed in classrooms (not just chemistry classrooms) but is often placed too high on the wall for anyone to make out more than the element symbols and atomic numbers. Periodic tables hung this way really serve as banners or flags and declare to anyone who enters the room that “We're doing science here.” [1]: pending:yes [2]: http://www.iypt2019.org

The Philosopher’s Stone of Reprogramming

A hierarchical transcriptional mechanism governs direct conversion of mouse embryonic fibroblasts to neurons.

Automated RNA Structure Prediction Uncovers a Kink-Turn Linker in Double Glycine Riboswitches

The tertiary structures of functional RNA molecules remain difficult to decipher. A new generation of automated RNA structure prediction methods may help address these challenges but have not yet been experimentally validated. Here we apply four prediction tools to a class of double glycine riboswitches that can bind two ligands cooperatively. A novel method (BPPalign), RMdetect, JAR3D, and Rosetta 3D modeling give consistent predictions for a new stem P0 and a kink-turn motif. These elements structure the linker between the RNAs' double aptamers. Chemical mapping on the Fusobacterium nucleatum riboswitch with N-methylisatoic anhydride, dimethyl sulfate and 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide metho-p-toluenesulfonate probing, mutate-and-map studies, and mutation/rescue experiments all provide strong evidence for the structured linker. Under solution conditions that permit rigorous thermodynamic analysis, disrupting this helix-junction-helix structure gives 120- and 6-30-fold poorer dissociation constants for the RNA's two glycine-binding transitions, corresponding to an overall energetic impact of 4.3 ± 0.5 kcal/mol. Prior biochemical and crystallography studies did not include this critical element due to over-truncation of the RNA. We speculate that several further undiscovered elements are likely to exist in the flanking regions of this and other functional RNAs, and automated prediction tools can play a useful role in their detection and dissection.

Covalency in f-element bonds

The actinide concept proposed by Seaborg in 1945 involves a close relationship between the trivalent 4f (Ln) and the 5f (An) elements. The trivalent ions of these two families have very similar properties due to strong ionic bonding and similar ionic radii. Their similarity led to the successful formation of element 95–103 over the next 30 years by accurate prediction of the chemistry of the undiscovered elements. In the early 1950s, a small degree of covalency was proposed in the bonding of the lanthanide elements. However, controversy continues today on the degree of covalency in the bonds of the 4f and 5f elements. The interpretation of data in terms of covalency in the M–L bonds is reviewed with emphasis on which orbitals are involved.

Production and decay of element 120

Abstract We discuss decay properties of nuclei predicted to be a result of a sequence of decays initiated by a so far undiscovered element 120. This element might be obtained in the reaction 208 Pb 126 ( 88 Sr 50 ,1 n ) 295 120 175 . The synthesis of 295 120 175 , if successful, might be observed by measurement of α -decay energy and half-life for nuclei in its decay chain.

Sir Johan Gadolin of Turku: the grandfather of gadolinium.

Acad Radiol 1996;3:S 165-$169 9 1996, Association of University Radiologists J ohan Gadolin was 33 years old in the spring of 1794, when his most important work was published [1]. In 28.5 pages, he carefully described his detailed chemical analysis of a new, black, heavy mineral that had recently been discovered at the Ytterby quarry on the island of Roslaga near Stockholm. A small sample had been given to him by the supervisor of the quarry in 1792. From it, he concluded that 38% of the mineral consisted of a previously undiscovered element. He named this substance ytterbia after the village near the quarry, but the name was soon shortened to yttria. The substance that he discovered was actually yttrium oxide, and it was the first of the so-called rare earths to be discovered and isolated [2]. The mineral from which he had isolated yttrium oxide soon acquired the name gadolinite in his honor. Although Gadolin and other chemists initially believed that he had discovered a new element, in 1808 Sir Humphry Davy showed that metallic earths are oxides, not pure elements. The rare-earth elements caused chemists considerable confusion for the next half century until tile introduction of the spectroscope in 1859 (99 years after Gadolin's birth) and Dmitri Mendeleev's first report of his periodic table in 1870. It was not until 1880, 120 years after Gadolin's birth, that Swiss chemist Jean-Charles-Galinard de Marignac isolated gadolinium oxide. The French chemist Paul-l~mile Lecoq de Boisbaudmn, a codiscoverer of gadolinium oxide, persuaded de Marignac to name this gadolinia. This occurred in 1886, 34 years after Gadolin's death. Pure elemental, metallic gadolinium was first purified in 1935 by French chemist E Trombe [2]. Gadolinium is not particularly rare, ranking 43rd among the elements in abundance, and it is 10 times more abundant than iodine. Among its many uses, it is a fluorescent agent in television screens and X-ray intensifying screens [2]. Since Hanns-Joachim Weinmann's pioneering work in 1981 [3], chelates of gadolinium have been introduced as tile first and, until 1995, tile only commercial paramagnetic contrast media used for magnetic resonance (MR) imaging.

Evolution of the Modern Periodic Table

In this review, the evolution of the Modern Periodic Table is traced beginning with the original version of Dimitri Mendeleev in 1869. Emphasis is placed on the upper end with a description of the revision to accommodate the actinide series of elements at the time of World War II and the more recent research on the observed and predicted chemical properties of the transactinide elements (beyond atomic number 103). A Modern Periodic Table includes undiscovered elements up to atomic number 118 and a Futuristic Periodic Table with additional undiscovered elements up to atomic number 168 is included.

Taxonomy in Psychology: Looking for Subatomic Units

Abstract A taxonomy is a model helpful in subsequent theory building because it provides lawful representation of the elements that comprise a theory. A taxonomy also permits scientists to predict the internal structure of previously undiscovered elements. Though taxonomic abstractions exist in the vernacular and in the practice of psychology, no scheme comparable to that of the Linnaean or Mendeleev systems in biology or chemistry has been developed. The following discussion suggests a method for developing any of three such schemes from the systematic explication of “subatomic” units of behavior.

Origin of unusual radioactive haloes

Abstract Formation of some enigmatic haloes (such as giant, super-giant, intermediate types, dwarf, polonium haloes etc.) has been explained, in an unified approach, on the basis of α-recoil and α-particle damage density distribution from the decay series of radon and thoron diffusing out of the highly radiation damaged inclusion and the surrounding host matrix. It is shown that the origin of these haloes can be explained without invoking the presence of any hitherto undiscovered radioelement or superheavy element in the halo inclusion. An order of magnitude estimate of the diffusion coefficient has been made. The data available in literature on different haloes have been shown to fit in well with the diffusion mechanism.

Eka-eka-lead?

The author points out the origin of the prefix eka used by Mendeleev to designate undiscovered elements.

The Transuranium Elements

UNTIL the past decade and a half, authors of textbooks of chemistry were not in the least reluctant to state that uranium, with an atomic number of 92, filled in the last space in the periodic table. They predicted that, in all probability, there remained no undiscovered elements. Since 1940, however, periodic charts have been under constant revision, and, at the present time the list of known chemical elements totals 98. Discovery of elements 93 through 98, the transuranium elements, is accredited to two University of California scientists, Edwin Mattison McMillan and Glenn Theodore Seaborg, and their associates. Their combined discoveries opened the doors to a great unknown and led to science's highest accolade, the Nobel prize in chemistry, which was jointly awarded to them last month in Stockholm, Sweden. Early Claims of Transuranium Elements Investigation of nuclear fission was the starting point which eventually led to the discovery of elements heavier than uranium. ...

The Future of Literary Scholarship

O NE might summarily describe literary scholarship in the nineteenth century as a continuous struggle between the philologists and the historians. In the one corner, we had the philologists. They were influenced by the new discoveries in chemistry and geology. They tried to break literature also into its elements-words. Each word they subjected to analysis, studying its roots and variations. As the chemists postulated undiscovered elements in their table and the astronomers undiscovered planets, they could formulate a Sanskrit word that they had not yet found. In their studies the beauties of literature, the rhythms of poetry, the structure of drama were lost in the pursuit of each separate word. Such was philology, scholarship made in Germany, the science of language. In the other corner were the historians. They sought not for elements but for links in the great chain of being. Darwin was their hero; they applied evolution not merely to horses and men but to the drama, the ode, the novel. Under their scrutiny the once Dark Ages became the Middle Ages. Sources, parallels, influences were their concern. The masterpieces were not broken up into separate words by them, but were hidden under webs of cross reference. After their analyses, the finest literary tapestry looked like a patchwork quilt. Through the late nineteenth century the warfare between the schools continued. Literary history was the easier task, but each university needed also its philologist, born or trained in Germany, as a sign of real scholarship. But the twentieth century saw a change in this warfare one side undermined, the other victorious. The study of the history and origin of words may be dying slowly-but it is dying surely. Ancient languages, and some modern ones, have gone out of the high schools and almost out of the colleges. In i900 a student might enter college with four years of Latin, two of Greek, two of German, and two of French. In I94i he would be unlikely to enter the graduate school with that equipment. The linguistic teacher may discover in each graduate class a student with the gift of tongues but never a whole class. The study of comparative philology may still have a few disciples, in phonetic laboratories or dialectic excursions, but most of its followers have turned to other fields. On the other hand, the historians have flourished. Sources, parallels,

Predicting Undiscovered Elements: Part Two: "A Classic of Science"

Predicting Undiscovered Elements: Part Two: "A Classic of Science"

A Possible Origin of the Nebular Lines

THE hypothesis that the lines of unknown origin in the spectra of nebulae are due to the atom of some hitherto undiscovered element (“ nebulium ”) is not the only one that may be advanced. The recently developed quantum theory of band spectra makes it at least possible that these lines could have their origin in a molecule with small moment of inertia composed of atoms of those elements which are known to exist in nebulae. It is proposed in this letter to show that the existing astronomical evidence is not in contradiction to this alternative hypothesis, and also to indulge in some speculation as to the nature of such a molecule.

A System of Inorganic Chemistry

DURING the twenty-five years or so which have elapsed since the recognition of the periodic law of the chemical elements as a valid relationship, the pronounced influence which it has exercised both on the aspect and aims of chemical science cannot be questioned. Whether in the prediction of undiscovered elements, or as an indicator of needful research, especially in the department of atomic weight estimations, it has met with signal success. In connecting the physical properties of the elements themselves and of their compounds with atomic weight, it has opened up new fields of investigation, and thrown fresh interest into old ones. Properties so widely different as those measured by refraction equivalent and breaking stress find an explanation, nowadays, in the magnitudes of the atomic weights.