Products of particlelike representations of the homogeneous Lorentz group are used to construct the degrees of spin angular momentum of a composite system of protons and neutrons. If a canonical labeling system is adopted for each state, a shell structure emerges. Furthermore the use of the Dirac ring ensures that the spin is characterized by half-angles in accord with the neutron-rotation experiment. It is possible to construct a Clebsch-Gordan decomposition to reduce a state of complex angular momentum into simpler (...) states which can be identified with α and β particles, multipole operators, etc. Finally, ground-state energy levels are calculated for all the even-even nuclei by using a differentiable manifold that is spin-graded and gauge-invariant by construction. It is shown that this manifold is Grassmann. (shrink)

We provide a detailed history of the concepts of atomic number and isotopy before the discovery of protons and neutrons that draws attention to the role of evolving interplays of multiple aims and criteria in chemical and physical research. Focusing on research by Frederick Soddy and Ernest Rutherford, we show that, in the context of differentiating disciplinary projects, the adoption of a complex and shifting concept of elemental identity and the ordering role of the periodic table led to a relatively (...) coherent notion of atomic number. Subsequent attention to valency, still neglected in the secondary literature, and to nuclear charge led to a decoupling of the concepts of elemental identity and weight and allowed for a coherent concept of isotopy. This concept received motivation from empirical investigations on the decomposition series of radioelements and their unstable chemical identity. A new model of chemical order was the result of an ongoing collaboration between chemical and physical research projects with evolving aims and standards. After key concepts were considered resolved and their territories were clarified, chemistry and physics resumed autonomous projects, yet remained bound by newly accepted explanatory relations. It is an episode of scientific collaboration and partial integration without simple, wholesale gestalt switches or chemical revolutions. (shrink)

The relevance of exchange effects for the stability of superheavy nuclei is examined within a linear QHD-II model by comparing Hartree-Fock with meanfield results. To allow a scan of the complete superheavy regime the recently developed local density approximation (LDA) for the exchange potential is employed for the Hartree-Fock level calculations. It turns out that, while many nuclear properties obtained with the LDA approach differ significantly from the corresponding mean-field results, the predictions of the two methods for shell closures (...) are very similar. Furthermore, a comparison with a nonlinear variant of QHD-II shows that many nuclear properties obtained with the LDA in the framework of linear QHD-II are somewhere in-between the corresponding linear and nonlinear mean-field results. This indicates that the LDA exchange partially includes nonlinear contributions, which supports the interpretation of the meson self-coupling as a parametrization of many-body effects. (shrink)

The nuclear envelope has recently become the object of intense scrutiny because it is the site of nuclear transport and is possibly involved in the organization of the interphase genome, thereby affecting gene expression. The major structural support for the nuclear envelope is the nuclear lamina, composed of the nuclear lamin proteins. They lie on the surface of the inner nuclear membrane and are in direct contact with the chromatin at the edge of the (...) nucleus. The structure of the nuclear lamin proteins has recently been deduced from their cDNAs and shown to have remarkable homologies to the family of cytoplasmic intermediate filaments. However, the lamin proteins have been found to depolymerize in response to metaphase‐specific phosphorylation events, and reassemble around daughter chromosomes at the completion of cell division. Little is known of the mechanisms of these dynamics, nor of other post‐translational modifications evident in these proteins. In addition, we have as yet no concrete idea of the function of these highly conserved proteins in the cell. This review will summarize our present knowledge of nuclear lamin structure and the new experimental approaches designed to elucidate their function. (shrink)

It is now clear that two prominent nuclear domains, interchromatin granule clusters (IGCs) and Cajal bodies (CBs), contribute to the highly ordered organization of the extrachromosomal space of the cell nucleus. These functional domains represent structurally stable but highly dynamic nuclear organelles enriched in factors that are required for different nuclear activities, especially RNA biogenesis. IGCs are considered to be the main sites for storage, assembly, and/or recycling of the essential spliceosome components. CBs are involved in the (...) biogenesis of several classes of small RNPs as well as the modification of newly assembled small nuclear RNA. We have summarized data on the molecular composition, structure, and functional roles of IGCs and CBs in the nuclei of mammalian somatic cells and oocytes of some animals with a special focus on insects. We have focused on similarities and differences between the IGCs and CBs of oocytes and the well‐studied CBs and IGCs of cultured mammalian somatic cells. We have shown the heterogeneous character of oocyte IGCs and CBs, both in structure and molecular content. We have also demonstrated the unique capacity of oocytes to form close structural interactions between IGC and CB components. We proposed to consider these joint structures as integrated entities, sharing the features of both IGCs and CBs. (shrink)

The solution structures of several small proteins have recently been determined from high‐resolution nuclear magnetic resonance data. The principal features of the methods available to do this are outlined here, together with the advantages, limitations and future prospects of the technique.

Nuclear pore complexes mediate and control transport between the cytosol and the nucleus. They form a highly selective and, thus, tight nuclear barrier between these compartments. The nuclear barrier provides the cell with the opportunity to control access to its DNA, a defining feature of eukaryotes. The tightness of the nuclear barrier is therefore physiologically pivotal and any remarkable change in its structure and permeability can prove pathophysiological, e.g. as a result of viral attack. However, (...) there is accumulating evidence that nuclear barrier structure and permeability are highly responsive to hydrophobic cargos of crucial physiological and therapeutic relevance, glucocorticoids (steroid hormones). The present review highlights the glucocorticoid‐induced effects on the nuclear barrier structure and permeability concluding that they are physiologically essential to mediate glucocorticoid action. BioEssays 28: 935–942, 2006. © 2006 Wiley periodicals, Inc. (shrink)

In higher eukaryotes, ‘replication factories’ coordinate DNA synthesis within local clusters of chromatin domains. Recent experiments(1,2) have confirmed the complexity of these clusters and established that the organization of sites labelled during S phase persists throughout the cell cycle. This implies that domain clusters are critical elements of an hierarchy that is fundamental to both nuclear and chromosome structure.

Remarkable advances in cold fusion, known also as LENR, raised the hope for a safer and cheaper nuclear energy. The results, however, cannot be explained from the point of view of current physical understanding of nuclear fusion. This is an obstacle for research investment in this field. The present book suggests a new approach for analysis of the experimental results and practical recommendations based on the models of atomic nuclei derived in the BSM-Supergravitation Unified theory (BSM-SG). The book (...) provides: (1) a method for analysis of the LENR experiments using the BSM-SG atomic models; (b) a selection of isotopes suitable for a more efficient energy yield with a minimum of radioactive byproducts; (c) practical considerations for selection of the technical method and the reaction environment. (shrink)

The double membrane of the nuclear envelope is a formidable barrier separating the nucleus and cytoplasm of eukaryotic cells. However, movement of specific macromolecules across the nuclear envelope is critical for embryonic development, cell growth and differentiation. Transfer of molecules between the nucleus and cytoplasm occurs through the aqueous channel formed by the nuclear pore complex (NPC)Abbreviations: NPC, nuclear pore complex; GlcNac, N‐acetylglucosamine; WGA, wheat germ agglutinin. Although small molecules may simply diffuse across the NPC, transport (...) of large proteins and RNA requires specific transport signals and is energy dependent. A family of pore glycoproteins modified by O‐linked N‐acetylglucosamine moieties are essential for transport through the NPC. Recent evidence suggests that the regulation of nuclear transport may also involve the inteaction of RNA and nuclear proteins with specific binding proteins that recognize these transport signals. Are these nuclear pore glycoproteins and signal binding proteins the ‘gatekeepers’ that control access to the genetic material? Recent evidence obtained from a combination of biochemical and genetic approaches suggests – perhaps. (shrink)

Magic angle spinning (MAS) NMR methods provide a means of obtaining high resolution structural data on rhodopsin and its photoin termediates. Current work has focused on the structure of the retinal chromophore and its interactions with surrounding protein charges. The recent development of MAS NMR methods for measuring internuclear distances with a resolution of ∼0.2 will complement diffraction methods for addressing key mechanistic questions.

The specificity of eukaryotic DNA organization into loops fixed to the nuclear matrix/chromosomal scaffold has been studied for more than fifteen years. The results and conclusions of different authors remain, however, controversial. Recently, we have elaborated a new approach to the study of chromosomal DNA loops. Instead of characterizing loop basements (nuclear matrix DNA), we have concentrated our efforts on the characterization of individual loops after their excision by DNA topoisomerase II‐mediated DNA cleavage at matrix attachment sites. In (...) this review the results of applying this mapping approach are compared with the results and conclusions from studies of nuclear matrix DNA. An attempt is also made to reconsider all data about the specificity of DNA interactions with the nuclear matrix and to suggest a model of spatial organization of the eukaryotic genome which resolves apparent contradictions between these data. (shrink)

Increasing interest has been paid to applications of fluorescence measurements to analyze physiological mechanisms in living cells. However, few studies have taken advantage of DNA quantification by fluorometry for dynamic assessment of chromatin organization as well as cell motion during the cell cycle. This approach involves both optimal conditions for DNA staining and cell tracking methods. In this context, this report describes a stoichiometric method for nuclear DNA specific staining, using the bisbenzimidazole dye Hoechst 33342 associated with verapamil, a (...) calcium membrane channel blocker. This method makes it possible to correlate variations of nuclear DNA content with cell motion in cells that are maintained alive. Motion measurement is the second goal of this paper and it explains the snake-spline method, and the associated cell following method. (shrink)

Three‐dimensional structured illumination microscopy (3D‐SIM) has opened up new possibilities to study nuclear architecture at the ultrastructural level down to the ∼100 nm range. We present first results and assess the potential using 3D‐SIM in combination with 3D fluorescence in situ hybridization (3D‐FISH) for the topographical analysis of defined nuclear targets. Our study also deals with the concern that artifacts produced by FISH may counteract the gain in resolution. We address the topography of DAPI‐stained DNA in nuclei before (...) and after 3D‐FISH, nuclear pores and the lamina, chromosome territories, chromatin domains, and individual gene loci. We also look at the replication patterns of chromocenters and the topographical relationship of Xist‐RNA within the inactive X‐territory. These examples demonstrate that an appropriately adapted 3D‐FISH/3D‐SIM approach preserves key characteristics of the nuclear ultrastructure and that the gain in information obtained by 3D‐SIM yields new insights into the functional nuclear organization. (shrink)

Within the highly organized nuclear structure, specific nuclear domains (ND10) are defined by accumulations of proteins that can be interferon-upregulated, implicating ND10 as sites of a nuclear defense mechanism.Compatible with such a mechanism is the deposition of herpesvirus, adenovirus, and papovavirus genomes at the periphery of ND10. However, these DNA viruses begin their transcription at ND10 and consequently initiate replication at these sites, suggesting that viruses have evolved ways to circumvent this potential cellular defense and exploit (...) it. Other ND10-associated proteins belong to ubiquitin-related pathways. These findings, together with the accumulation of various overexpressed cellular and viral proteins, suggest that ND10 function as nuclear dumps or as nuclear depots. Consistent with the recruitment or deposition of various proteins and viral genomes adjacent to ND10, ND10 themselves may only be protein accumulations at specific but as yet undefined nuclear deposition sites. The concept of specific nuclear deposition sites may explain the juxtaposition of various nuclear bodies and allows testable predictions about a potential supramolecular regulatory mechanism whereby proteins are selectively segregated or released by global changes induced in nuclear functions such as viral infections, stress, or hormonal induction. BioEssays 20:660–667, 1998.© 1998 John Wiley & Sons Inc. (shrink)

Within the highly organized nuclear structure, specific nuclear domains (ND10) are defined by accumulations of proteins that can be interferon-upregulated, implicating ND10 as sites of a nuclear defense mechanism.Compatible with such a mechanism is the deposition of herpesvirus, adenovirus, and papovavirus genomes at the periphery of ND10. However, these DNA viruses begin their transcription at ND10 and consequently initiate replication at these sites, suggesting that viruses have evolved ways to circumvent this potential cellular defense and exploit (...) it. Other ND10-associated proteins belong to ubiquitin-related pathways. These findings, together with the accumulation of various overexpressed cellular and viral proteins, suggest that ND10 function as nuclear dumps or as nuclear depots. Consistent with the recruitment or deposition of various proteins and viral genomes adjacent to ND10, ND10 themselves may only be protein accumulations at specific but as yet undefined nuclear deposition sites. The concept of specific nuclear deposition sites may explain the juxtaposition of various nuclear bodies and allows testable predictions about a potential supramolecular regulatory mechanism whereby proteins are selectively segregated or released by global changes induced in nuclear functions such as viral infections, stress, or hormonal induction. BioEssays 20:660–667, 1998.© 1998 John Wiley & Sons Inc. (shrink)

Paraspeckles are nuclear condensates, or membranelees organelles, that are built on the long noncoding RNA, NEAT1, and have been linked to many diseases. Although originally described as constitutive structures, here, in reviewing this field, we develop the hypothesis that cells increase paraspeckle abundance as part of a general stress response, to aid pro‐survival pathways. Paraspeckles increase in many scenarios: when cells transform from one state to another, become infected with viruses and bacteria, begin to degenerate, under inflammation, in aging, (...) and in cancer. Cells increase paraspeckles by increasing transcription of NEAT1 and adjusting its RNA processing. These increases in NEAT1 are driven by numerous stress‐sensing signaling pathways, including signaling to mitochondria and stress granules, revealing crosstalk between the cytoplasm and nucleoplasm in the stress response. Thus, paraspeckles are an important piece of the puzzle in cellular homeostasis, and could be considered RNA‐scaffolded nuclear equivalents of dynamic stress‐induced structures that form in the cytoplasm. We speculate that, in general, cells rely on phase‐separated paraspeckles to transiently tweak gene regulation in times of cellular flux. (shrink)

Transport of macromolecules from the nucleus to the cytoplasm is essential for nearly all cellular and developmental events, and when mis‐regulated, is associated with diseases, tumor formation/growth, and cancer progression. Nuclear Envelope (NE)‐budding is a newly appreciated nuclear export pathway for large macromolecular machineries, including those assembled to allow co‐regulation of functionally related components, that bypasses canonical nuclear export through nuclear pores. In this pathway, large macromolecular complexes are enveloped by the inner nuclear membrane, transverse (...) the perinuclear space, and then exit through the outer nuclear membrane to release its contents into the cytoplasm. NE‐budding is a conserved process and shares many features with nuclear egress mechanisms used by herpesviruses. Despite its biological importance and clinical relevance, little is yet known about the regulatory and structural machineries that allow NE‐budding to occur in any system. Here we summarize what is currently known or proposed for this intriguing nuclear export process. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Direct Nuclear Reprogramming: Response to Condic, Lee, and GeorgeGerard Magill, Ph.D. and William B. NeavesWe read with great interest the response of Maureen Condic, Patrick Lee, and Robert George (2009) to our essay, “Ontological and Ethical Implications of Direct Nuclear Reprogramming” in the March 2009 issue of the Kennedy Institute of Ethics Journal (Magill and Neaves 2009). Much of their response addressed issues that are not in (...) dispute: somatic cells are not zygotes, neurons and hepatocytes are different, growth-factor signals from the trophoblast influence development of the inner cell mass, membranes derived from the trophectoderm are critically required for embryonic survival, and stem cells cannot produce a fetus “on their own.”The crucial point of disagreement deals with the fact that iPS cells are not totipotent but zygotes are. Zygotes can generate their own placental structures while iPS cells must be given them through tetraploid complementation. Condic, Lee, and George consider totipotency to be crucial to natural potentiality. We present an alternative view in our essay (Magill and Neaves 2009, pp. 28–29). Placental structures make no lasting contribution to the postnatal organism, and the equivalency of iPS cells with the inner cell mass of the blastocyst is apparent from tetraploid complementation experiments.The respondents acknowledge the following:... somatic cells can be “converted” into zygotes by the process of somatic cell nuclear transfer (SCNT) or direct reprogramming in combination with tetraploid complementation—just as sperm and egg cells can be “converted” into a zygote by the process of natural fertilization—....(Condic, Lee, and George 2009, p. 35)As the respondents recognize, different ways of manipulating cells can lead to embryogenesis: sperm and egg cells in the process of natural fertilization, the enucleated egg and an ordinary body cell in the process of somatic cell nuclear transfer, and reprogrammed skin cells and a tetraploid blastocyst in the case of induced pluripotent stem (iPS) cells. In each case, different cells are manipulated—or “converted” in the respondents’ terminology—in a process that alters their biological fate within a supportive environment facilitating embryogenesis.The developmental potential that resides in the human genome does not unfold in isolation, not even in a zygote. In all cases, whether involving a zygote or an iPS cell, interaction with a supportive environment is required to express the developmental program residing in the genome. [End Page 201]This biological reality supports what we have described as “early cellular development along the continuum of natural potentiality that can result in the formation of a fetus” (Magill and Neaves 2009, p. 30), and it presents a significant challenge to the natural potentiality argument.Gerard MagillVernon F. Gallagher Chair for the Integration of Science, Theology, Philosophy, and Law, and Professor, Center for Healthcare Ethics Duquesne University Pittsburgh, PA.William B. NeavesPresident and CEO Stowers Institute for Medical Research and Professor of Basic Medical Science University of Missouri at Kansas City School of Medicine Kansas City, MOReferencesCondic, Maureen L.; Lee, Patrick; and George, Robert P. 2008. Ontological and Ethical Implications of Direct Nuclear Reprogramming: Response to Magill and Neaves. Kennedy Institute of Ethics Journal 19: 33–40. Google ScholarMagill, Gerard, and Neaves William B. 2009. Ontological and Ethical Implications of Direct Nuclear Reprogramming. Kennedy Institute of Ethics Journal 19: 23–32. Google ScholarCopyright © 2009 The Johns Hopkins University Press... (shrink)

Given the known hazards of nuclear energy in seismically active Japan after the Fukushima meltdowns as well as the presence of viable conservation and renewable energy options, the question of Japan’s stalled energy transition warrants critical interrogation. To better understand why, after Fukushima, Japan’s energy policy trajectory maintained the nuclear status quo and an increased reliance on fossil fuels, this article employs network and historical analyses to examine the confluence of post-Fukushima political forces connected to Japan’s nuclear (...) energy sector. Our novel network dataset combines with historical analysis to identify a dense network of overlapping executives and officials in Japan that forge long-term ties between the nuclear energy industry, the state, and the leading business federation in Japan. Following the 3.11 disaster and the meltdowns at the Fukushima-Daiichi facility, a long-standing nuclear safety myth and a tightly networked nuclear energy industrial complex provided an ideological and structural context to re-legitimize nuclear energy in spite of widespread public concern. Instead of a bold, ecologically rational policy to quickly phase out nuclear power and phase in renewable energy, well-worn class and state networks aligned to recommit Japan to a nuclear-reliant energy path. These findings support a theoretical synthesis around our concept of an energy industrial complex with applications in environmental and political sociology. (shrink)

Mammalian telomeres have evolved safeguards to prevent their recognition as DNA double‐stranded breaks by suppressing the activation of various DNA sensing and repair proteins. We have shown that the telomere‐binding proteins TRF2 and RAP1 cooperate to prevent telomeres from undergoing aberrant homology‐directed recombination by mediating t‐loop protection. Our recent findings also suggest that mammalian telomere‐binding proteins interact with the nuclear envelope to maintain chromosome stability. RAP1 interacts with nuclear lamins through KU70/KU80, and disruption of RAP1 and TRF2 function (...) result in nuclear envelope rupture, promoting telomere‐telomere recombination to form structures termed ultrabright telomeres. In this review, we discuss the importance of the interactions between shelterin components and the nuclear envelope to maintain telomere homeostasis and genome stability. (shrink)

Nuclear intermolecular duplexes appear to be a general feature of nucleated cells. Most of these duplexes are formed between large RNA as well as between large and small RNA molecules. A significant portion of the large molecules belong to a special class of RNA that is restricted to the nucleus and, therefore, not designated for export. These molecules are assembled with proteins and form a structure of a higher order. The possibility that these molecules and a set of (...) small nuclear RNAs are components of a complex machine, “the transportosome”, which functions in nucleocytoplasmic traffic, is discussed. (shrink)

The export of processed RNA molecules from the nucleus is an intricately regulated process, subject to various developmental and physiological controls. The structural and biochemical properties of the nuclear envelope that are involved in this process are described here.

This book examines, through a multi-disciplinary lens, the possibilities offered by relationships and family forms that challenge the nuclear family ideal, and some of the arguments that recommend or disqualify these as legitimate units in our societies. That children should be conceived naturally, born to and raised by their two young, heterosexual, married to each other, genetic parents; that this relationship between parents is also the ideal relationship between romantic or sexual partners; and that romance and sexual intimacy ought (...) to be at the core of our closest personal relationships - all these elements converge towards the ideal of the nuclear family. The authors consider a range of relationship and family structures that depart from this ideal: polyamory and polygamy, single and polyparenting, parenting by gay and lesbian couples, as well as families created through current and prospective modes of assisted human reproduction such as surrogate motherhood, donor insemination, and reproductive cloning. (shrink)

Novel forms of matter, such as states made of gluons (glueballs), multiquark mesons or baryons and hybrid mesons are predicted by low energy QCD, for which several candidates have recently been identified. Searching for such exotic states of matter and studying their production and decay properties in detail has become a flourishing field at the experimental facilities now available or being built - e.g. BESIII in Beijing, BELLE II at SuperKEKB, GlueX at Jefferson Lab, PANDA at FAIR, J-PARC and in (...) the upgraded LHC experiments, in particular LHCb. A modern primer in the field is required so as to both revive and update the teaching of a new generation of researchers in the field of QCD. These lectures on hadron spectroscopy are intended for Master and PhD students and have been originally developed for a course delivered at the Stefan Meyer Institute of the Austrian Academy of Sciences. They are phenomenologically oriented and intended as complementary material for basic courses in particle and nuclear physics. The book describes the spectra of light and heavy mesons and baryons, and introduces the fundamental properties based on symmetries. Further, it derives multiplet structures, mixing angle, decay coupling constants, magnetic moments of baryons, and predictions for multiquark states and compares these with suitable experimental data. Basic methods of calculating decay angular distributions and determining masses and widths of resonances are also presented. The appendices provide students and newcomers to the field with the necessary background information, and include a set of problems and solutions. (shrink)

The multifunctional zinc‐finger protein CCCTC‐binding factor (CTCF) is a very strong candidate for the role of coordinating the expression level of coding sequences with their three‐dimensional position in the nucleus, apparently responding to a “code” in the DNA itself. Dynamic interactions between chromatin fibers in the context of nuclear architecture have been implicated in various aspects of genome functions. However, the molecular basis of these interactions still remains elusive and is a subject of intense debate. Here we discuss the (...) nature of CTCF‐DNA interactions, the CTCF‐binding specificity to its binding sites and the relationship between CTCF and chromatin, and we examine data linking CTCF with gene regulation in the three‐dimensional nuclear space. We discuss why these features render CTCF a very strong candidate for the role and propose a unifying model, the “CTCF code,” explaining the mechanistic basis of how the information encrypted in DNA may be interpreted by CTCF into diverse nuclear functions. (shrink)

Recent events have put the acceptability of the risks of nuclear energy production technologies under the spotlight. A focus on risks, however, could lead to the neglect of other aspects of NEPT, such as their irreversibility. I argue that awareness of the socio-historical development of NEPT is helpful for understanding their irreversibility. To this end, I conceptualize NEPT development as a process of structuration in which material, institutional and discursive elements are produced and/or reproduced by purposive social actors. This (...) conceptualization is used to structure an analysis of how irreversibility arose in the first decades of NEPT development in India, France and the USA, and how some NEPT have been reversed or partially reversed. Lastly, two general conditions for reversible NEPT are formulated based on this analysis. (shrink)

The theory of Yin and Yang and the Five Movements is based on the concept of cyclical time. This ancient cosmological model postulates that when expansive energy reaches its apex, mutual life-saving relations prevail over mutually conflictual societal relations, and that this cycle repeats. This cosmic change model was first presented in ancient Korea and China, by Hado-Nakseo, via numerological configurations and symbols. The Hado diagram was drawn by a Korean thinker, Bok-hui (?-BC3413), also known as Great Empeor Fuzi or (...) Fu-hsi in Chinese mythology. Confucius once recognized him as the father of I Ching (Book of Changes). The Eastern cosmology was further developed by King Wen and the Duke of Zhou and compiled by Confucius (BC551?-BC 479) during the Spring and Autumn Period and the Warring States Period. Nakseo diagram was first discovered by the famous King Wu of China, who founded the Xia dynasty. In contrast to the harmonious mathematical matrix of Hado, Nakseo symbolizes the conflictual and dynamic expansion of the universe. In the Nakseo world, masculine energy is structurally greater than feminine energy, continuously breeding disequilibrium and conflict. The Yin and Yang model suggests that everything in the universe exists as a combination of opposing dynamics. At any given time, one of the two dynamics grows while the other declines. When Yang energy is at its peak, Yin energy is at its nadir; then, a reversal occurs; and envetually the whole cycle repeats. It would thus be logical to express that when conflictual energy has reached its apex harmonious energy begins to wax. It can be argued that since the state of disequilibrium within the universe represented by Nakseo cannot indefinitely sustain its dynamic of expansion, harmonious international relationships eventually come to pervade the world. This argument represents a unique applicationof the concept of Yin and Yang logic to international arms race and arms control. This cyclical dynamics can explain the long-term process of arms build-up followed by eventually by nuclear standoff and subsequent nuclear arms control regimes as NPT, CTBT, MTCR, SALT, START, PSI and etc. One can boldly claim that Yin and Yang logic offers a clue to creating a theory of structural peace by discovering a constructivist element in the model. The esoteric matrixes of ancient Korea and China thus provide humanity with an new vision for nuclear disarmament and a sustainable peace. (shrink)

The nuclear pore complex (NPC) is emerging as a center for recruitment of a class of “difficult to repair” lesions such as double‐strand breaks without a repair template and eroded telomeres in telomerase‐deficient cells. In addition to such pathological situations, a recent study by Su and colleagues shows that also physiological threats to genome integrity such as DNA secondary structure‐forming triplet repeat sequences relocalize to the NPC during DNA replication. Mutants that fail to reposition the triplet repeat locus (...) to the NPC cause repeat instability. Here, we review the types of DNA lesions that relocalize to the NPC, the putative mechanisms of relocalization, and the types of recombinational repair that are stimulated by the NPC, and present a model for NPC‐facilitated repair. (shrink)

ArgumentThis article describes the efforts of one fifty-year-old nuclear physics research center to stay relevant as the boundaries of nuclear physics have expanded and distributed collaborations have become increasingly common. In adapting to these shifts, SENSE, a university-based institute in the United States, has seen notable changes in power relations, forms of legitimation, and social structures. This article recognizes and investigates these changes through an interpretative investigation of four common media objects incorporated into research practice at the institute: (...) collaboration wikis, telephones, computer simulations, and government reports. In doing so, this article adopts an approach from media studies through which hard-to-see changes in social and cultural life can be investigated by observing media objects in research practice. Ultimately, this article tells the story of a research organization and an entire discipline working to adapt to a rapidly changing scientific landscape. (shrink)

In eukaryotic cells, messenger RNAs are formed by extensive posttranscriptional processing of primary transcripts, assembled with a large number of proteins and processing factors in ribonucleoprotein complexes. The protein moiety of these complexes mainly constitutes a class of about 20 major polypeptides called heterogeneous nuclear ribonucleoproteins or hnRNPs. The function and the mechanism of action of hnRNPs is still not fully understood, but the identification of RNA binding domains and RNA binding specificities, and the development of new functional assays, (...) has stimulated interest in them. In contrast to previous models that hypothesised a mere structural (histone‐like) function, a more diversified and dynamic role for these proteins is now emerging. In fact, they can be viewed as a subset of the trans‐acting pre‐mRNA maturation factors. They might actively participate in post‐transcriptional events such as regulated splicing and mRNA export. Moreover, recent data suggest an involvement of some of these proteins in molecular diseases. Here we present an overview of the most relevant properties of hnRNPs and discuss some emerging ideas on theiir roles. (shrink)

Thomas Kuhn's Structure of Scientific Revolutions became the most widely read book about science in the twentieth century. His terms 'paradigm' and 'scientific revolution' entered everyday speech, but they remain controversial. In the second half of the twentieth century, the new field of cognitive science combined empirical psychology, computer science, and neuroscience. In this book, the theories of concepts developed by cognitive scientists are used to evaluate and extend Kuhn's most influential ideas. Based on case studies of the Copernican (...) revolution, the discovery of nuclear fission, and an elaboration of Kuhn's famous 'ducks and geese' example of concept learning, this volume, first published in 2006, offers accounts of the nature of normal and revolutionary science, the function of anomalies, and the nature of incommensurability. (shrink)

Following with the discovery of the electron by J. J. Thomson at the end of the nineteenth century a steady elucidation of the structure of the atom occurred over the next 40 years culminating in the discovery of nuclear fission in 1938–1939. The significant steps after the electron discovery were: discovery of the nuclear atom by Rutherford (Philos Mag 6th Ser 21:669–688, 1911 ), the transformation of elements by Rutherford (Philos Mag 37:578–587, 1919 ), discovery of artificial (...) radioactivity by Joliot-Curie and Joliot-Curie (Comptes Rendus Acad Sci Paris 198:254–256, 1934 ), and the discovery of the neutron by Chadwick (Nature 129:312, 1932a , Proc R Soc Ser A 136:692–708, 1932b ; Proc R Soc Lond Ser A 136:744–748, 1932c ). The neutron furnished scientists with a particle able to penetrate atomic nuclei without expenditure of large amounts of energy. From 1934 until 1938–1939 investigations of the reaction between a neutron and uranium were carried out by E. Fermi in Rome, O. Hahn, L. Meitner and F. Strassmann in Berlin and I. Curie and P. Savitch in Paris. Results were interpreted as the formation of transuranic elements. After sorting out complex radio-chemistry and radio-physics O. Hahn and F. Strassmann came to the conclusion, beyond their belief, that the uranium nucleus split into smaller fragments, that is nuclear fission. This was soon followed in 1939 by its theoretical interpretation by L. Mietner and O. Frisch. (shrink)

Plastids and mitochondria arose through endosymbiotic acquisition of formerly free-living bacteria. During more than a billion years of subsequent concerted evolution, the three genomes of plant cells have undergone dramatic structural changes to optimize the expression of the compartmentalized genetic material and to fine-tune the communication between the nucleus and the organelles. The chimeric composition of many multiprotein complexes in plastids and mitochondria (one part of the subunits being nuclear encoded and another one being encoded in the organellar genome) (...) provides a paradigm for co-evolution at the cellular level. In this paper, we discuss the co-evolution of nuclear and organellar genomes in the context of environmental adaptation in species and populations. We highlight emerging genetic model systems and new experimental approaches that are particularly suitable to elucidate the molecular basis of co-adaptation processes and describe how nuclear-cytoplasmic co-evolution can cause genetic incompatibilities that contribute to the establishment of hybridization barriers, ultimately leading to the formation of new species. (shrink)

The International Court of Justice advisory opinion on the Legality of the Threat or Use of Nuclear Weapons in 1996 was a landmark case because, for the first time in history, the legal aspect of nuclear weapons was addressed. The decision has evoked controversies regarding the Court’s conclusion, the legal status of international humanitarian law in relation to nuclear weapons, and a newly introduced concept of state survival. While much legal scholarship discusses and criticizes the legal significance (...) of the opinion, there has not been enough scholarship examining the Court’s specific choice of words and concepts that sustain its wider ideological and political position in the opinion. The paper argues that the Court’s vague and controversial logic is attributed to its confrontation with two international orders/codes: the legal order and the political order. The paper engages in legal semiotics as methodology to decode legal text and discover a deep structure that sustains networks of codes, according to which text is interpreted. Through the semiotic examination of three sets of key concepts “permitted” and “prohibited,” “threat of use” and “possession of the weapon,” and “state survival,” the paper shows the ICJ’s confrontation with two orders/codes and eventual prioritization of the political order over the international legal order. The analysis of the opinion based on legal semiotics indicates an intimate and inseparable relationship between state practice and international law, which must be disentangled for the sake of the rule of law. (shrink)

Rapidly advancing studies on rhodopsin have focused on new strategies for crystallization of this integral membrane protein for x-ray analysis and on alternative methods for structural determination from nuclear magnetic resonance data. Functional studies of the interactions between the apoprotein and its chromophore have clarified the role of the chromophore in deactivation of opsin and in photoactivation of the pigment.

Drawing upon the concepts of civic epistemologies and sociotechnical imaginaries, this article delves into the history of nuclear energy in Portugal, analyzing the ways in which the nuclear endeavor was differently enacted by various sociopolitical collectives – the Fascist State, post-revolutionary governments and the public. Following the 1974 revolution - known as the Carnation Revolution - this paper analyzes how the nuclear project was fiercely contested by a vibrant anti-nuclear movement assembled against the construction of the (...) Ferrel Nuclear Plant, the first sociotechnical controversy in Portugal, paving the way for the emergence of a combative civic epistemology. Supported by semi-structured interviews with scientists, activists and local residents of Ferrel and the analysis of historical material, this article presents the failed Portuguese nuclear endeavor as an emblematic case study to explore the co-production of science and society, in particular the role of revolutionary processes in the unfolding of sociotechnical controversies. (shrink)

John Canaday, The Nuclear Muse: Literature, Physics, and the First Atomic Bombs. Madison: University of Wisconsin Press, 2000. Pp. xviii+310. ISBN 0-299-16854-9. £19.50.Septimus H. Paul, Nuclear Rivals: Anglo-American Atomic Relations 1941–1952. Columbus: Ohio State University Press, 2000. Pp. ix+266. ISBN 0-8142-0852-5. £31.95.Peter Bacon Hales, Atomic Spaces: Living on the Manhattan Project. Urbana and Chicago: University of Illinois Press, 1997. Pp. 448. ISBN 0-252-02296-3. £22.00.A decade after the end of the Cold War, the culture and technology of nuclear (...) weapons had lost much of the overt sense of dread they once inspired. The decline in international tension following the end of the communist regimes of the Soviet bloc produced a massive shift in the ideology of the nuclear in the 1990s. The de-targeting and dismantling of large numbers of nuclear weapons and the demise of the threat of nuclear annihilation created new conditions both for international security and for the writing of nuclear history. With the declassification and release of large quantities of official documentation from the former adversaries, as well as the fiftieth anniversary of the bombings of Hiroshima and Nagasaki in 1995, a burst of histories of various aspects of the nuclear age have appeared over the last ten years, exploring not just the technopolitics, strategy and operational logistics of the Cold War and the arms race, but the cultural history of the nuclear age, its imagery, its architecture, its oppositional politics and its effects on the landscape, national and regional economies and cultures and indeed everyday life. At a time of global economic and political uncertainty and the emergent threat of capricious international terrorism and new nuclear proliferation, the apparent certainties of the Cold War now even evoke a certain nostalgia, and its artefacts and structures are being recast as ‘heritage’. (shrink)

It may be that eukaryotic nuclei contain a collection of operationally independent units (genes), each controlled through its interactions with soluble protein factors which diffuse at random throughout the nucleoplasmic space. Alternatively, nuclei might be organized in such a sophisticated fashion that specific genes, occupy distinct sites and that spatially ordered RNA synthesis, processing and transport delivers mature RNAs to predestined sites in the cytoplasm.Different fields of research support each of these extreme views. Molecular biologists inspecting the precise details of (...) specific interactions, usually in vitro, inevitably favour the former, while cell biologists working with far more complicated systems generally assume that more elaborate arrangements exist. In considering the importance of nuclear architecture, I have attempted to relate a collection of experiments each of which intimates some close relationship between structural aspects of chromatin organization and the precise mechanisms underlying nuclear function. I will argue that higherorder structures are crucial for achieving the observed efficiency and coordination of many nuclear processes. (shrink)

This essay explores the faultlines, poetic pressures and social structures of feeling determining poetry “after” Hiroshima. Nuclear bombs, accidents and waste pose theoretical and poetic challenges. The argument outlines a model of nuclear implicature that reworks Gricean conversational implicature. Nuclear implicature helps to describe ways in which poems “represent” nuclear problems implicitly rather than explicitly. Metonymic, metaphorical, and grammatical modes of implication are juxtaposed with recognition of social attitudes complicit with nuclear problems. Mushroom and lichen (...) metaphors are analysed and distinguished. There are brief accounts of The Chernobyl Herbarium, The Nuclear Culture Source Book and poems by Aidan Semmens, Lorine Niedecker, George Oppen, Denise Levertov, Adrienne Rich, Allen Ginsberg and Gerry Loose. The argument attempts to keep open the fragile agency of writing in poems that confront nuclear power. Poetry after Hiroshima is also contrasted with Adorno’s provocative questions about poetry after Auschwitz, amid Cold War arguments that have distorted recognition of the reality of nuclear production. The essay concludes by considering the emergence of poetry within E.P. Thompson’s theoretical account of “Exterminism,” sketching ways in which poetics and theory might inform both the nuclear imagination and the difficulties of nuclear song. (shrink)

Basic proteins and nucleic acids are assembled into complexes in a reaction that must be facilitated by nuclear chaperones in order to prevent protein aggregation and formation of non‐specific nucleoprotein complexes. The nucleophosmin/nucleoplasmin (NPM) family of chaperones [NPM1 (nucleophosmin), NPM2 (nucleoplasmin) and NPM3] have diverse functions in the cell and are ubiquitously represented throughout the animal kingdom. The importance of this family in cellular processes such as chromatin remodeling, genome stability, ribosome biogenesis, DNA duplication and transcriptional regulation has led (...) to the rapid growth of information available on their structure and function. The present review covers different aspects related to the structure, evolution and function of the NPM family. Emphasis is placed on the long‐term evolutionary mechanisms leading to the functional diversification of the family members, their role as chaperones (particularly as it pertains to their ability to aid in the reprogramming of chromatin), and the importance of NPM2 as an essential component of the amphibian chromatin remodeling machinery during fertilization and early embryonic development. BioEssays 29: 49–59, 2007. © 2006 Wiley Periodicals, Inc. (shrink)

Literature expects that an attitude toward nuclear power is in direct proportion to the perceived risk of accidents at an operational nuclear power plant; that is, the oppositional attitude is based on the view that nuclear technology is risky and support for nuclear power is related to a perceived low risk and/or potential benefit. However, it is misleading to assume that individuals’ risk perception alone can linearly explain their position after such an accident. The association between (...) risk perception and attitude toward nuclear power varies significantly according to country but, until now, has been largely unexamined. This article takes into consideration the effects of structural factors on that relationship by examining public attitudes toward nuclear energy after the Fukushima nuclear accident in March 2011 and reveals that the need for the efficient production of electricity (i.e., nuclear energy) outweighs concern for the potential danger of a nuclear incident. Although a country's dependence on nuclear power for the production of electricity engenders anti-nuclear attitudes, it is evident that a level of economic development largely alleviates any negativity relative to that energy source. (shrink)

Despite the radical changes in the global political and military situation in the past ten years, U.S. nuclear forces retain the same mission and the same basic structure they had when Moscow was the seat of the “Evil Empire.” As it has for decades, the United States maintains thousands of nuclear warheads on a variety of land-, sea- and air-based platforms. These forces are on a level of high alert, ready to launch within minutes of an attack (...) warning. It is a distinctly Cold War footing in a world that has long since come in from the cold of U.S.–Soviet antagonism. (shrink)

The objective of this article is to examine the nature of individual and social responses to the nuclear threat from psychological and sociological perspectives on ignorance. It is argued that a constructed and managed ignorance concerning the nuclear threat serves many functions, structuring an individual and social reality which is reassuring, meaningful, and both individually and collectively self-serving. A sociology of ignorance framework is employed to articulate the possible benefits of “not knowing about” and collaboratively “not dealing with” (...) the nuclear threat, as well as to define the longer-term costs of ignoring this threat. The distinctive roles played by various kinds of ignorance regarding this important issue are investigated, and the conventional wisdom that knowledge of the consequences of a nuclear war is the only way to prevent its occurrence is challenged. (shrink)

Results of two survey studies are presented. It is shown that attitudes of the public about "technology in general" are not stable and can easily be affected by how the subject is introduced. Eight areas of technology are compared on the basis of empirical relations in attitudinal judgments, in attribute ratings, in self- assigned importance weights of attributes, and in importance of reference groups and persons. On the basis of similarities in these four kinds of judgments, three clusters of technology (...) areas were identified: a cluster of modern reproductive technologies, an information cluster containing automation, computer, and communication technologies, and a cluster containing nuclear energy and military technology. The attitude toward "technology in general" can not be considered as an aggregation of attitudes toward these areas of technology: The relations between general attitude and specific attitudes are only moderate to negligible. (shrink)

Relativistic mean field theory with mesons σ, ω, π and ρ mediating interactions and nucleons as basic fermions has been very successful in describing nuclear matter and finite nuclei. However, in heavy-ion collisions, where the c. m. energy of two colliding nucleons will be in the hundreds of GeV region, nucleons are not expected to behave as point-like particles. Analyses of elastic pp and ¯pp scattering data in the relevant c. m. energy range show that the nucleon is a (...) composite object—a topological soliton or Skyrmion embedded in a condensed quark-antiquark ground state. Against this backdrop, we formulate an effective field theory model of nuclear matter based on the gauged linear σ-model where quarks are the basic fermions, but the mesons still mediate the interactions. The model describes the nucleon as a Skyrmion and produces a q¯q ground state analogous to a superconducting ground state. Quarks are quasi-particles in this ground state. When the temperature exceeds a critical value, the scalar field in the ground state vanishes, quarks become massless, and a chiral phase transition occurs leading to chiral symmetry restoration. We explore the possibility of a first order phase transition in this model by introducing suitable self-interactions of the scalar field. Internal structures of the Skyrmions are ignored, and they are treated as point-like fermions. (shrink)