Indirect Searches of the Degenerate MSSM

A degenerate sfermionic particle spectrum can escape constraints from flavor physics, and at the same time evade the limits from the direct searches if the degeneracy extends to the gaugino-higgsino sector. Inspired by this, we consider a scenario where all the soft terms have an approximately common mass scale at $M_{\text{SUSY}}$, with splittings $\lesssim \mathcal{O}(10\%)$. As a result, the third generation sfermions have large to maximal (left-right) mixing, the same being the case with charginos and some sectors of the neutralino mass matrix. We study this scenario in the light of discovery of the Higgs boson with mass $\sim$ 125 GeV. We consider constraints from $B$-physics, the anomalous magnetic moment of the muon and the dark matter relic density. We find that a supersymmetric spectrum as light as 600 GeV could be consistent with all current data and also account for the observed anomalous magnetic moment of the muon within $2\sigma$. The neutralino relic density is generally too small to saturate the measured cold dark matter relic density. Direct detection limits from XENON100 and LUX put severe constraints on this scenario which will be conclusively probed by XENONnT experiment.Comment: 27 pages, 8 figures; Comments welcom

Fermion Dipole Moments in Supersymmetric Models with Explicitly Broken R-parity

We present a simple analysis that allows us to extract the leading mass dependence of the dipole moment of matter fermions that might be induced by new physics. We present explicit results for the supersymmetric model with broken R-parity as an illustration. We show that the extra contributions to the electric dipole moment (edm) of fermions from R-parity violating interactions can occur only at two loop level, contrary to claims in the literature. We further find that unlike the generic lepto-quark models, the extra contributions to the dipole moments of the leptons can only be enhanced by m_b/m_l and not by m_t/m_l relative to the expectations in the Standard Model. An interesting feature about this enhancement of these dipole moments is that it does not involve unknown mixing angles. We then use experimental constraints on the electric dipole moments of electron and neutron to obtain bounds on (the imaginary part of) products of R-parity violating couplings, and show that bounds claimed in the literature are too stringent by many orders of magnitude.Comment: 16 pages latex, 7 figure

The Mouse Hindbrain As a Model for Studying Embryonic Neurogenesis

The mouse embryo forebrain is the most commonly employed system for studying mammalian neurogenesis during development. However, the highly folded forebrain neuroepithelium is not amenable to wholemount analysis to examine organ-wide neurogenesis patterns. Moreover, defining the mechanisms of forebrain neurogenesis is not necessarily predictive of neurogenesis in other parts of the brain; for example, due to the presence of forebrain-specific progenitor subtypes. The mouse hindbrain provides an alternative model for studying embryonic neurogenesis that is amenable to wholemount analysis, as well as tissue sections to observe the spatiotemporal distribution and behavior of neural progenitors. Moreover, it is easily dissected for other downstream applications, such as cell isolation or molecular biology analysis. As the mouse hindbrain can be readily analyzed in the vast number of cell lineage reporter and mutant mouse strains that have become available, it offers a powerful model for studying the cellular and molecular mechanisms of developmental neurogenesis in a mammalian organism. Here, we present a simple and quick method to use the mouse embryo hindbrain for analyzing mammalian neural progenitor cell (NPC) behavior in wholemount preparations and tissue sections

Cross-talk between blood vessels and neural progenitors in the developing brain

The formation of the central nervous system (CNS) involves multiple cellular and molecular interactions between neural progenitor cells (NPCs) and blood vessels to establish extensive and complex neural networks and attract a vascular supply that support their function. In this review, we discuss studies that have performed genetic manipulations of chick, fish and mouse embryos to define the spatiotemporal roles of molecules that mediate the reciprocal regulation of NPCs and blood vessels. These experiments have highlighted core functions of NPC-expressed ligands in initiating vascular growth into and within the neural tube as well as establishing the blood-brain barrier. More recent findings have also revealed indispensable roles of blood vessels in regulating NPC expansion and eventual differentiation, and specific regional differences in the effect of angiocrine signals. Accordingly, NPCs initially stimulate blood vessel growth and maturation to nourish the brain, but blood vessels subsequently also regulate NPC behaviour to promote the formation of a sufficient number and diversity of neural cells. A greater understanding of the molecular cross-talk between NPCs and blood vessels will improve our knowledge of how the vertebrate nervous system forms and likely help in the design of novel therapies aimed at regenerating neurons and neural vasculature following CNS disease or injury

Probing SUSY beyond the reach of LEP2 at the Fermilab Tevatron: low |M_3| dark matter models

In supersymmetric models where the magnitude of the GUT scale gaugino mass parameter M_3 is suppressed relative to M_1 and M_2, the lightest neutralino can be a mixed higgsino-bino state with a thermal relic abundance in agreement with the WMAP central value for \Omega_{\rm CDM} h^2 and consistent with all other phenomenological constraints. In these models, the gluino can be as light as 200 GeV without conflicting with the LEP2 bounds on the chargino mass. Thus, gluino pair production can be accessible at the Fermilab Tevatron at high rates. In this framework, gluinos decay radiatively with a large branching fraction to a gluon plus a neutralino. We find that experiments at the Fermilab Tevatron, with 5 fb^{-1} of integrated luminosity, will be sensitive to gluino pair production in the m_{\tg}\sim 200-350 GeV range via the multi-jet +etmissing and multi-jet +\ell^+\ell^- + etmissing channels at the 5\sigma level, while trilepton signatures are expected to be below this level of detectability. Dilepton mass edges from both \tz_2 and \tz_3 decays may be measurable in the dilepton + multi-jet +etmissing channel.Comment: 14 pages including 6 EPS figure

A scalable system for microcalcification cluster automated detection in a distributed mammographic database

A computer-aided detection (CADe) system for microcalcification cluster identification in mammograms has been developed in the framework of the EU-founded MammoGrid project. The CADe software is mainly based on wavelet transforms and artificial neural networks. It is able to identify microcalcifications in different datasets of mammograms (i.e. acquired with different machines and settings, digitized with different pitch and bit depth or direct digital ones). The CADe can be remotely run from GRID-connected acquisition and annotation stations, supporting clinicians from geographically distant locations in the interpretation of mammographic data. We report and discuss the system performances on different datasets of mammograms and the status of the GRID-enabled CADe analysis.Comment: 6 pages, 4 figures; Proceedings of the IEEE NNS and MIC Conference, October 23-29, 2005, Puerto Ric

Addressing \mu-b_\mu and proton lifetime problems and active neutrino masses in a U(1)^\prime-extended supergravity model

We present a locally supersymmetric extension of the minimal supersymmetric Standard Model (MSSM) based on the gauge group $SU(3)_C\times SU(2)_L\times U(1)_Y\times U(1)^\prime$ where, except for the supersymmetry breaking scale which is fixed to be $\sim 10^{11}$ GeV, we require that all non-Standard-Model parameters allowed by the {\it local} spacetime and gauge symmetries assume their natural values. The $U(1)^\prime$ symmetry, which is spontaneously broken at the intermediate scale, serves to ({\it i}) explain the weak scale magnitudes of $\mu$ and $b_\mu$ terms, ({\it ii}) ensure that dimension-3 and dimension-4 baryon-number-violating superpotential operators are forbidden, solving the proton-lifetime problem, ({\it iii}) predict {\it bilinear lepton number violation} in the superpotential at just the right level to accommodate the observed mass and mixing pattern of active neutrinos (leading to a novel connection between the SUSY breaking scale and neutrino masses), while corresponding trilinear operators are strongly supppressed. The phenomenology is like that of the MSSM with bilinear R-parity violation, were the would-be lightest supersymmetric particle decays leptonically with a lifetime of $\sim 10^{-12}-10^{-8}$ s. Theoretical consistency of our model requires the existence of multi-TeV, stable, colour-triplet, weak-isosinglet scalars or fermions, with either conventional or exotic electric charge which should be readily detectable if they are within the kinematic reach of a hadron collider. Null results of searches for heavy exotic isotopes implies that the re-heating temperature of our Universe must have been below their mass scale which, in turn, suggests that sphalerons play a key role for baryogensis. Finally, the dark matter cannot be the weakly interacting neutralino.Comment: 33 pages, 2 figures, Discussion on proton decay and radiative neutrino masses augmented, and references adde

Sentencing and plea bargaining : guilty pleas versus trial verdicts

In the daily work of the criminal justice process, the relationship between plea decision-making and sentencing is one of the most important. Meanwhile, in the academic and policy literatures it is one of the most controversial. This essay examines the moral arguments for and against the practice of altering a sentence as a consequence of a plea of “not guilty” or “guilty”. It also appraises the state of international empirical knowledge about the practice and raises questions for future research. It is widely believed that a defendant who pleads guilty is likely to receive a reduced sentence if s/he pleads ‘guilty’ than if s/he is found guilty, as a result of a trial, of exactly the same charges. Various terms are used to describe this practice (e.g. “Sentence Reduction”, “Guilty Plea Discount”, “Sentence Deduction”, “allowance in respect of a guilty plea”, “Trial Penalty”, et cetera.). However, as discussed below, these terms are value laden and imply different normative positions. Thus, in the interests of neutrality, this essay will generally use the term “Plea-Dependent Sentence Differential” (or “Sentence Differential” for short). The foundation for the Sentence Differential varies depending on the jurisdiction. In some jurisdictions statue or case law may permit, or even require, a Sentence Differential. In others the basis of the Sentence Differential is found in guideline schemes. In certain jurisdictions the Sentence Differential may have little formal basis and is routed in the informal practices of sentencers. However, regardless of its basis, in most criminal justice systems there is a widely held perception that there is a Sentence Differential. This essay will provide an overview of the main issues and debates resulting from the Sentence Differential. In doing so, it also raises some provocative questions and suggestions for future research, not least the pressing need for a fuller appreciation of defendants’ perspectives and decision-making

Process Capability Database Usage In Industry: Myth vs. Reality

Process capability data (PCD) is needed for robust design, optimal tolerance allocation, and variation simulation analysis. Process capability databases (PCDBs) have been developed in many industries and are being used by the manufacturing community to monitor quality; however, they are not being effectively utilized by design. When the PCDBs1 were developed, the intent was for design to use PCD for optimization and product cost minimization, but this ideal situation has not been realized. A survey of a variety of design and manufacturing companies was circulated to determine both the state-ofthe- art in PCDBs and the barriers preventing design from fully utilizing PCD. Two key barriers were identified for internal PCDBs: lack of a company-wide vision for PCD usage and poor communication between manufacturing and design. Supplier PCDBs have the additional barriers of lack of trust between suppliers and customers and time lag for data entry. Management support, training, database population, and common systems were identified as potential solutions to the identified barriers