Weapon Division (W-DO) Weapon Surety and Military Liaison Group (W-10) Weapons 101 Overview
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This paper opens a new door to macroscopic modeling for thermal and chemical non-equilibrium. In a game-changing approach, we discard conventional theories and practices stemming from the separation of internal energy modes and the Landau-Teller relaxation equation. Instead, we solve the fundamental microscopic equations in their moment forms but seek only optimum representations for the microscopic state distribution function that provides converged and time accurate solutions for certain macroscopic quantities at all times. The modeling makes no ad hoc assumptions or simplifications at the microscopic level and includes all possible collisional and radiative processes; it therefore retains all non-equilibrium fluid physics. We formulate the thermal and chemical non-equilibrium macroscopic equations and rate coefficients in a coupled and unified fashion for gases undergoing completely general transitions. All collisional partners can have internal structures and can change their internal energy states after transitions. The model is based on the reconstruction of the state distribution function. The internal energy space is subdivided into multiple groups in order to better describe non-equilibrium state distributions. The logarithm of the distribution function in each group is expressed as a power series in internal energy based on the maximum entropy principle. The method of weighted residuals is applied to the microscopic equations to obtain macroscopic moment equations and rate coefficients succinctly to any order. The model’s accuracy depends only on the assumed expression of the state distribution function and the number of groups used and can be self-checked for accuracy and convergence. We show that the macroscopic internal energy transfer, similar to mass and momentum transfers, occurs through nonlinear collisional processes and is not a simple relaxation process described by, e.g., the Landau-Teller equation. Unlike the classical vibrational energy relaxation model, which can only be applied to molecules, the new model is applicable to atoms, molecules, ions, and their mixtures. Numerical examples and model validations are carried out with two gas mixtures using the maximum entropy linear model: one mixture consists of nitrogen molecules undergoing internal excitation and dissociation and the other consists of nitrogen atoms undergoing internal excitation and ionization. Results show that the original hundreds to thousands of microscopic equations can be reduced to two macroscopic equations with almost perfect agreement for the total number density and total internal energy using only one or two groups. We also obtain good prediction of the microscopic state populations using 5-10 groups in the macroscopic equations.
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Obtaining a unified description of the quasi-degenerate neutrino mass spectrum together with the hierarchical charged fermions is a challenging task. In this talk, we discuss two distinct possible scenarios leading to such spectra in the supersymmetric SO(10) grand unified framework. Consistency of both scenarios is demonstrated through detailed fits to fermion masses and mixing angles, all of which can be explained with reasonable accuracy in a model with the most general Yukawa sector of SO(10). The origin of large neutrino mixing angles is linked to neutrino mass degeneracy in both the scenarios.
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Recently type-II seesaw in a supersymmetricSO(10) framework has been found useful in explaining large solar and atmospheric mixing angles as well as a larger value of {theta}{sub 13} while unifying quark and lepton masses. An important question in these models is whether there exists consistency between coupling unification and type-II seesaw dominance. Scenarios where this consistency can be demonstrated have been given in a SUSY framework. In this paper we give examples where type-II dominance occurs in SO(10) models without supersymmetry but with additional TeV-scale particles and also in models with split-supersymmetry. Grand unification is realized in a two step process via breaking of SO(10) to SU(5) and then to a TeV-scale standard model supplemented by extra fields and an SU(5) Higgs multiplet 15{sub H} at a scale of about 10{sup 12} GeV to give a type-II seesaw. The predictions for proton lifetime in these models are in the range {tau}{sub p}{sup 0}=2x10{sup 35} yrs. to 6x10{sup 35} yrs. A number of recent numerical fits to GUT-scale fermion masses can be accommodated within this model.
We consider an SU(3){sub c} x SU(2){sub L} x SU(2){sub R} x U(1){sub B-L} left-right symmetric model with three Higgs scalars including an SU(2){sub L} doublet, an SU(2){sub R} doublet and an SU(2){sub L} x SU(2){sub R} bidoublet. In addition to usual SU(2)-doublet fermions, our model contains SU(2)-triplet fermions with Majorana masses. The neutral components of the left-handed triplets can contribute a canonical seesaw while the neutral components of the right-handed triplets associated with the right-handed neutrinos can contribute a double/inverse-type seesaw. Our model can be embedded into an SO(10) grand unification theory where the triplets belong to the 45=(1,3,1,0)+(1,1,3,0)+... representations.
We analyse the prospects for constructing hybrid models of inflation that provide a dynamical realisation of the apparent closeness between the supersymmetric GUT scale and the possible scale of cosmological inflation. In the first place, we consider models based on the flipped SU(5)×U(1) gauge group, which has no magnetic monopoles. In one model, the inflaton is identified with a sneutrino field, and in the other model it is a gauge singlet. In both cases we find regions of the model parameter spaces that are compatible with the experimental magnitudes of the scalar perturbations, A{sub s}, and the tilt in the scalar perturbation spectrum, n{sub s}, as well as with an indicative upper limit on the tensor-to-scalar perturbation ratio, r. We also discuss embeddings of these models into SO(10), which is broken at a higher scale so that its monopoles are inflated away.
Hepatocellular carcinoma (HCC) is one of the most common cancers and can be induced by chronic HBV infection. The role of HBV-specific immune responses in mediating tumorigenesis and HCC prognosis is debated. The effect of intratumoral microenvironment on tumor-infiltrating lymphocytes (TILs) is also unclear. Here, we examined resected tumor tissue from 36 patients with HBV-induced HCC. We categorized study cohort based on ex vivo IL-10 secretion by tumor cells into high IL-10-secreting (Hi10) and low IL-10-secreting (Lo10) groups, and found that the Lo10 group was less sensitive to TLR ligand stimulation. TILs from the Lo10 group contained higher frequencies of HBV-specific IFN-g-producing cells and total IFN-g-producing cells, and possessed higher proliferative capacity. Moreover, the proliferative capacity of TILs from the Hi10 group was negatively correlated with IL-10 secretion from tumor cells. Together, our data demonstrated that low IL-10-producing capacity in HBV-induced HCC tumors is associated with enhanced TIL activity. - Highlights: • We examined intratumoral IL-10 production in HBV-induced HCC. • We grouped HCC tumors into Hi10 and Lo10 groups based on their IL-10 production. • Lo10 groups had better IFN-g response by TILs. • Lo10 groups had better TIL proliferative capacity. • Lo10 group tumor cells were refractory to TLR ligand stimulation.
We study SO(10), SU(5) and flipped SU(5) GUT models with non-universal soft supersymmetry-breaking scalar masses, exploring how they are constrained by LHC supersymmetry searches and cold dark matter experiments, and how they can be probed and distinguished in future experiments. We find characteristic differences between the various GUT scenarios, particularly in the coannihilation region, which is very sensitive to changes of parameters. For example, the flipped SU(5) GUT predicts the possibility of ∼t{sub 1}−χ coannihilation, which is absent in the regions of the SO(10) and SU(5) GUT parameter spaces that we study. We use the relic density predictions in different models to determine upper bounds for the neutralino masses, and we find large differences between different GUT models in the sparticle spectra for the same LSP mass, leading to direct connections of distinctive possible experimental measurements with the structure of the GUT group. We find that future LHC searches for generic missing E{sub T}, charginos and stops will be able to constrain the different GUT models in complementary ways, as will the Xenon 1 ton and Darwin dark matter scattering experiments and future FERMI or CTA γ-ray searches.
A previous report of a novel pneumovirus (PnV) isolated from the respiratory tract of a dog described its significant homology to the rodent pathogen, pneumonia virus of mice (PVM). The original PnV–Ane4 pathogen replicated in and could be re-isolated in infectious state from mouse lung but elicited minimal mortality compared to PVM strain J3666. Here we assess phylogeny and physiologic responses to 10 new PnV isolates. The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to the characterized PVMs, and suggest division into groups A and B. While we observed significant differences in cytokine production and neutrophil recruitment to the lungs of BALB/c mice in response to survival doses (50 TCID{sub 50} units) of representative group A (114378-10-29-KY-F) and group B (7968-11-OK) PnVs, we observed no evidence for positive selection (dN>dS) among the PnV/PnV, PVM/PnV or PVM/PVM G/glycoprotein or F/fusion protein sequence pairs. - Highlights: • We consider ten novel isolates of the pneumovirus (PnV) first described by Renshaw and colleagues. • The G/glycoprotein sequences of all PnVs include elongated amino-termini when compared to PVM. • We detect cytokine production and neutrophil recruitment to the lungs of mice in response to PnV. • We observed no evidence for positive selection (dN>dS) among the gene sequence pairs.
Ziegler-type hydrogenation catalysts are important for industrial processes, namely, the large-scale selective hydrogenation of styrenic block copolymers. Ziegler-type hydrogenation catalysts are composed of a group 8-10 transition metal precatalyst plus an alkylaluminum cocatalyst (and they are not the same as Ziegler-Natta polymerization catalysts). However, for {approx}50 years two unsettled issues central to Ziegler-type hydrogenation catalysis are the nature of the metal species present after catalyst synthesis, and whether the species primarily responsible for catalytic hydrogenation activity are homogeneous (e.g., monometallic complexes) or heterogeneous (e.g., Ziegler nanoclusters defined as metal nanoclusters made from combination of Ziegler-type hydrogenation catalyst precursors). A critical review of the existing literature (Alley et al. J. Mol. Catal. A: Chem. 2010, 315, 1-27) and a recently published study using an Ir model system (Alley et al. Inorg. Chem. 2010, 49, 8131-8147) help to guide the present investigation of Ziegler-type hydrogenation catalysts made from the industrially favored precursors Co(neodecanoate){sub 2} or Ni(2-ethylhexanoate){sub 2}, plus AlEt{sub 3}. The approach and methods used herein parallel those used in the study of the Ir model system. Specifically, a combination of Z-contrast scanning transmission electron microscopy (STEM), matrix assisted laser desorption ionization mass spectrometry (MALDI MS), and X-ray absorption fine structure (XAFS) spectroscopy are used to characterize the transition metal species both before and after hydrogenation. Kinetic studies including Hg(0) poisoning experiments are utilized to test which species are the most active catalysts. The main findings are that, both before and after catalytic cyclohexene hydrogenation, the species present comprise a broad distribution of metal cluster sizes from subnanometer to nanometer scale particles, with estimated mean cluster diameters of about 1 nm for both Co and Ni. The XAFS results also imply that the catalyst solutions are a mixture of the metal clusters described above, plus unreduced metal ions. The kinetics-based Hg(0) poisoning evidence suggests that Co and Ni Ziegler nanoclusters (i.e., M{sub {ge}4}) are the most active Ziegler-type hydrogenation catalysts in these industrial systems. Overall, the novelty and primary conclusions of this study are as follows: (i) this study examines Co- and Ni-based catalysts made from the actual industrial precursor materials, catalysts that are notoriously problematic regarding their characterization; (ii) the Z-contrast STEM results reported herein represent, to our knowledge, the best microscopic analysis of the industrial Co and Ni Ziegler-type hydrogenation catalysts; (iii) this study is the first explicit application of an established method, using multiple analytical methods and kinetics-based studies, for distinguishing homogeneous from heterogeneous catalysis in these Ziegler-type systems; and (iv) this study parallels the successful study of an Ir model Ziegler catalyst system, thereby benefiting from a comparison to those previously unavailable findings, although the greater M-M bond energy, and tendency to agglomerate, of Ir versus Ni or Co are important differences to be noted. Overall, the main result of this work is that it provides the leading hypothesis going forward to try to refute in future work, namely, that sub, M{sub {ge}4} to larger, M{sub n} Ziegler nanoclusters are the dominant, industrial, Co- and Ni- plus AlR{sub 3} catalysts in Ziegler-type hydrogenation systems.
Minimal SO(10) models which utilize a 126-plet of Higgs for breaking B - L symmetry are predictive schemes for neutrino masses and mixings. These models have been known to predict sin{sup 2}2{theta}{sub 13} Asymptotically-Equal-To 0.09, which is consistent with recent measurements. It is shown that the same class of models generates naturally baryon number violating dimension seven operators leading to novel nucleon decay modes such as n{yields}e{sup -}K{sup +}, e{sup -}{pi}{sup +} and p{yields}{nu}{pi}{sup +} which violate B - L by two units. We find that in two-step breaking schemes of non-supersymmetric SO(10), the partial lifetimes for these modes can be within reach of experiments. The interactions responsible for these decay modes also provide a new way to understand the origin of matter in the universe via the decays of GUT scale colored scalar bosons. Their (B - L)-violating nature guarantees that the GUT scale induced baryon asymmetry is not washed out by the electroweak sphaleron interactions. In minimal SO(10) models this asymmetry is closely tied to the masses of quarks, leptons and the neutrinos.
Conventional SO(10) models involve more than one scale for a complete breaking of the GUT symmetry requiring further assumptions on the VEVs of the Higgs fields that enter in the breaking to achieve viable models. Recent works where the breaking can be accomplished at one scale are discussed. These include models with just a pair of 144+144 of Higgs fields. Further extensions of this idea utilizing 560+560 of Higgs representations allow both the breaking at one scale, as well as accomplish a natural doublet-triplet splitting via the missing partner mechanism. More generally, we discuss the connection of high scale models to low energy physics in the context of supergravity grand unification. Here we discuss a natural solution to the little hierarchy problem and also discuss the implications of the LHC data for supersymmetry. It is shown that the LHC data implies that most of the parameter space of supergravity models consistent with the data lie on the Hyperbolic Branch of radiative breaking of the electroweak symmetry and more specifically on the Focal Surface of the Hyperbolic Branch. A discussion is also given of the implications of recent LHC data on the Higgs boson mass for the discovery of supersymmetry and for the search for dark matter.
We argue that non-supersymmetric SO(10) models based on a renormalizable Higgs sector in which spontaneous symmetry breaking is triggered by the VEVs of a 45-dimensional adjoint and a 126-dimensional tensor representations can provide a potentially realistic yet relatively simple framework for a future robust estimate of the proton lifetime. Following closely the work [1] we comment on the gauge unification constraints on the B - L breaking scale and show that there are several regions in the parameter space of the minimal model where the seesaw scale in the phenomenologically favoured ballpark of around 10{sup 13 Division-Sign 14}GeV is consistently supported.
We employ third family Yukawa unification, predicted by simple supersymmetric SO(10) models, to estimate the lightest MSSM Higgs boson mass. For {mu} > 0 (or {mu} < 0) and m{sub t} = 173.1GeV, the Higgs mass is estimated to lie close to 123-124 GeV. The theoretical uncertainty in this estimate is {+-}3 GeV. We highlight some LHC testable benchmark points which also display the presence of neutralino-stau coannihilation channel.
Diverse mass and mixing patterns between the quarks and leptons makes it challenging to construct a simple grand unified theory of flavor. The SO(10) SUSY GUT with type II seesaw mechanism giving neutrino masses provide a natural framework for addressing this issue. Proton decay suppression is also an important issue to construct SUSY GUT models. We will investigate the flavor structure which are favored to suppress proton decay in SUSY GUT models. The structure in the SO(10) GUT model provides a prediction of the neutrino mixing, and the lepton flavor violating decays will be an important probe of the model.