Mycobacterium tuberculosis strains contain different genomic insertions or deletions called large sequence polymorphisms (LSPs). Distinguishing between LSPs that occur one time versus ones that occur repeatedly in a genomic region may provide insights into the biological roles of LSPs and identify useful phylogenetic markers. We analyzed 163 clinical M. tuberculosis isolates for 17 LSPs identified in a genomic comparison of M. tuberculosis strains H37Rv and CDC1551. LSPs were mapped onto a single-nucleotide polymorphism (SNP)-based phylogenetic tree created using nine novel SNP markers that were found to reproduce a 212-SNP-based phylogeny. Four LSPs (group A) mapped to a single SNP tree segment. Two LSPs (group B) and 11 LSPs (group C) were inferred to have arisen independently in the same genomic region either two or more than two times, respectively. None of the group A LSPs but one group B LSP and five group C LSPs were flanked by IS6110 sequences in the references strains. Genes encoding members of the proline-glutamic acid or proline-proline-glutamic acid protein families were present only in group B or C LSPs. SNP- versus LSP-based phylogenies were also compared. We classified each isolate into 58 LSP types by using a separate LSP-based phylogenetic analysis and mapped the LSP types onto the SNP tree. LSPs often assigned isolates to the correct phylogenetic lineage; however, significant mistakes occurred for 6/58 (10%) of the LSP types. In conclusion, most LSPs occur in genomic regions that are prone to repeated insertion/deletion events and were responsible for an unexpectedly high degree of genomic variation in clinical M. tuberculosis. Group B and C LSPs may represent polymorphisms that occur due to selective pressure and affect the phenotype of the organism, while group A LSPs are preferable phylogenetic markers.
The $R$-parity violating decays of Bino neutralino LSPs are analyzed within the context of the $B-L$ MSSM "heterotic standard model". These LSPs correspond to statistically determined initial soft supersymmetry breaking parameters which, when evolved using the renormalization group equations, lead to an effective theory satisfying all phenomenological requirements; including the observed electroweak vector boson masses and the Higgs mass. The explicit RPV decay channels of these LSPs into standard model particles, the analytic and numerical decay rates and the associated branching ratios are presented. The analysis of these quantities breaks into two separate calculations; first, for Bino neutralino LSPs with mass larger than $M_{W^{\pm}}$ and, second, when the Bino neutralino mass is smaller than the electroweak scale. The RPV decay processes in both of these regions is analyzed in detail. The decay lengths of these RPV interactions are discussed. It is shown that for heavy Bino neutralino LSPs the vast majority of these decays are "prompt", although a small, but calculable, number correspond to "displaced" decays of various lengths. The situation is reversed for light Bino LSPs,
Relatively light sneutrinos which are experimentally allowed and are not theoretically disfavoured may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible channel. In certain cases the second lightest neutralino may also decay invisibly leading to two extra carriers of missing energy (in addition to the lightest supersymmetric particle (LSP) ) - the virtual LSPs (VLSPs). The lighter charginos which would be produced in pairs with reasonably large cross-sections at TEVATRON energies, decay dominantly into the hadronically quiet lepton + sneutrino ($ ot{E_T}$ ) modes with large branching ratios leading to interesting unlike sign dilepton events which are not swamped by the standard model background. The kinematical cuts required to eliminate the backgrounds from WW, Drell-Yan and $τ$ pair production are discussed in detail. With 100 $pb^{-1}$ luminosity 10 - 35 background free events can be found in a large region of the SUSY parameter space.
Relatively light sneutrinos, which are experimentally allowed, may significantly affect the currently popular search strategies for supersymmetric particles by decaying dominantly into an invisible channel. In certain cases the second lightest neutralino may also decay invisibly leading to two extra carriers of missing energy -- in addition to the lightest supersymmetric particle (LSP) \zi\ -- the virtual LSPs (VLSPs). It is shown that these VLSPs are allowed in supergravity models with common scalar and gaugino masses at the unification scale for a sizable region of parameter space and are consistent with all constraints derived so far from SUSY searches. The pair production of right handed sleptons, which can very well be the lightest charged SUSY particles in this scenario, at LEP 200 and their decay signatures are discussed. The signal survives kinematical cuts required to remove the standard model background. Charginos are also pair produced copiously if kinematically accessible; they also decay dominantly into hadronically quiet di--lepton + \etmiss\ modes leading to interesting unlike sign dilepton events which are again easily separable from the Standard Model backgrounds a
Currently popular search strategies for supersymmetric particles may be significantly affected due to relatively light sneutrinos which decay dominantly into invisible channels. In certain cases the second lightest neutralino may also decay invisibly leading to two extra carriers of missing energy (in addition to the lightest supersymmetric particle (LSP)) -- the virtual LSPs (VLSPs). It is shown that if the sneutrino masses happen to be in the small but experimentally allowed range ~ 45 - 55 GeV, these particles together with neutralino pairs may contribute significantly to the missing energy in the process e+ e- ---> γ+ missing energy at LEP-2 energies as an enhancement over the Standard Model or the conventional MSSM predictions. It is further shown that a much larger region of the parameter space can be scanned at a high luminosity e+ e- collider at 500 GeV like the proposed NLC machine. Moreover this process can play a complementary role to direct chargino searches at LEP-2 and NLC which may fail due to a near mass degeneracy of the chargino and the sneutrino. Formulae for the cross sections taking into account full mixings of the charginos and the neutralinos are derived.
The $R$-parity violating decays of both Wino chargino and Wino neutralino LSPs are analyzed within the context of the $B-L$ MSSM "heterotic standard model". These LSPs correspond to statistically determined initial soft supersymmetry breaking parameters which, when evolved using the renormalization group equations, lead to an effective theory satisfying all phenomenological requirements; including the observed electroweak vector boson and Higgs masses. The explicit decay channels of these LSPs into standard model particles, the analytic and numerical decay rates and the associated branching ratios are presented. The decay lengths of these RPV interactions are discussed. It is shown that the vast majority of these decays are "prompt", although a small, but calculable, number correspond to "displaced vertices" of various lengths. It is demonstrated that for a Wino chargino LSP, the NLSP is the Wino neutralino with a mass only slightly higher than the LSP-- and vice-versa. As a consequence, we show that both the Wino chargino and Wino neutralino LSP/NLSP $R$-parity violating decays should be simultaneously observable at the CERN LHC.
We have examined the capability of the LHC, running at both 7 and 8 TeV, to explore the 19(20)-dimensional parameter space of the pMSSM with neutralino(gravitino) LSPs and soft masses up to 4 TeV employing the ATLAS SUSY analysis suite. Here we present some preliminary results for the gravitino model set, following the ATLAS analyses whose data were publically available as of mid-September 2012. We find that the impact of the reduced MET, resulting from models with gravitino LSPs on sparticle searches is more than off-set by the detectability of the many possible long-lived NLSPs.
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We explore the LHC phenomenology of the dark matter candidate arising from the extension of warped Higgsless models. In particular, we consider a model of warped supersymmetry in the bulk and on the IR brane in which the lightest Neutralino is rendered stable by an R parity and serves as a realistic cold dark matter candidate. The production of the LSP and NLSP in association with third generation quarks is simulated using an implementation in O'Mega/Whizard.
The pMSSM provides a broad perspective on SUSY phenomenology. In this paper we generate two new, very large, sets of pMSSM models with sparticle masses extending up to 4 TeV, where the lightest supersymmetric particle (LSP) is either a neutralino or gravitino. The existence of a gravitino LSP necessitates a detailed study of its cosmological effects and we find that Big Bang Nucleosynthesis places strong constraints on this scenario. Both sets are subjected to a global set of theoretical, observational and experimental constraints resulting in a sample of \sim 225k viable models for each LSP type. The characteristics of these two model sets are briefly compared. We confront the neutralino LSP model set with searches for SUSY at the 7 TeV LHC using both the missing (MET) and non-missing ET ATLAS analyses. In the MET case, we employ Monte Carlo estimates of the ratios of the SM backgrounds at 7 and 8 TeV to rescale the 7 TeV data-driven ATLAS backgrounds to 8 TeV. This allows us to determine the pMSSM parameter space coverage for this collision energy. We find that an integrated luminosity of \sim 5-20 fb^{-1} at 8 TeV would yield a substantial increase in this coverage compared to t
We consider the minimal supergravity model (mSUGRA) with one additional R-parity violating operator at the GUT scale. The superparticles mass spectra at the weak scale are generally altered due to the presence of the R-parity violating coupling in the renormalization group equations. We show that a lepton number violating coupling at the GUT scale can lead to a sneutrino as the lightest supersymmetric particle (LSP) in a large region of parameter space consistent with the muon anomalous magnetic moment and other precision measurements. We also give characteristic collider signatures at the LHC.
Purpose The purpose of this paper is to provide new insights into the reactions and lessons learned with regard to the COVID-19 pandemic in terms of how logistics service providers (LSPs) managed to maintain supply chains resilience and what focus areas have been changed to keep operations functional and uphold financial stability. Design/methodology/approach Based on data-gathering techniques in interpretive research this study collected primary data via semi-structured interviews, interviewing informants from selected LSPs that operate on a global scale. Findings The results show that LSPs have built their reactions and actions to the COVID-19 outbreak around five main themes: “create revenue streams,” “enhance operational transport flexibility,” “enforce digitalization and data management,” “optimize logistics infrastructure” and “optimize personnel capacity.” These pillars build the foundation to LSP resilience that enables supply chains to stay resilient during an external shock of high impact and low probability. Originality/value The results of this study provide insights into how LSPs have managed the downsides and found innovative ways to overcome operational and financial challenges during the COVID-19 outbreak. As one of the first studies that specially focuses on the role of LSPs during the COVID-19 pandemic, this study categorizes the LSPs’ reactions and provides a “lessons learned” framework from a managerial perspective. From a theoretical perspective, this paper discusses the strategic role of LSPs in supply chain management and thereby extends current supply chain literature with a focus on LSP resilience.
A liver-specific lipoprotein (LSP) which is present in 105,000 g supernatants of human liver has previously been shown to produce a lesion resembling chronic active hepatitis in rabbits immunized with human liver fractions containing this lipoprotein. In addition, it has been implicated as the principal target antigen involved in the liver cell cytotoxicity exhibited in vitro by lymphocytes from patients with chronic active hepatitis. The organ-specificity and species cross-reactivity of LSP is confirmed. Although very labile, is has been prepared in a stable form by gel filtration of Sepharose 6B in a Tris buffer containing 1 mm disodium EDTA. LSP is also stable in a borate buffer containing EDTA but is unstable in a number of other buffer systems tested. When prepared by this method it contains approximately 2% albumin as the only detectable contaminant. Gel filtration studies on the apoprotein of LSP revealed that it has an apparent mol. wt of between 4 X 10(6) and 20 X 10(6). SDA-polyacrylamide gel electrophoresis indicated that the lipoprotein may be composed of up to thirteen sub-units of different molecular sizes.
Liver specific membrane lipoprotein (LSP), the target for anti-LSP antibodies in various liver diseases, is thought to be comprised of fragments of the hepatocellular plasma membrane. In the present study, therefore, evidence has been sought for the presence in LSP of the hepatocyte surface receptor (hepatic lectin) that binds desialylated glycoproteins. Eight guinea-pig anti-LSP antisera (four anti-human and four anti-rabbit LSP) were found to react by ELISA and/or RIA against affinity purified human and rabbit hepatic lectin. Binding of the antisera to 125I-hepatic lectins was inhibited by the unlabelled lectins, by human and rabbit LSP and by purified rabbit liver plasma membranes but not by a 50,000-fold excess of kidney homogenate. The results indicate that hepatic lectin is a liver specific, species cross-reactive antigen comprising about 0.25% of the protein in LSP.
Approximately one-third of luminous pulsating red giant stars exhibit long secondary periods (LSPs): stable photometric variability with periods of several months to years in addition to their much shorter primary pulsation cycles. Now nearly a century after their discovery, the physical origin of LSPs remains unresolved. A leading explanation invokes binarity, in which the LSP corresponds to the orbital period of a low-mass companion responsible for both the photometric variability and the radial-velocity (RV) modulation. We test this hypothesis using a nearby sample of LSP stars from the {\it Gaia} Focused Product Release, which provides multi-epoch RVs and contemporaneous optical photometry. We find that interpreting the observed RV variability as orbital motion implies companion masses narrowly distributed around $M_2 \approx 0.1~{\rm M_\odot}$ with separations of 1--3 au, placing them squarely in the brown dwarf desert observed around their solar-type progenitors. Assuming such companions exist, we then forward-model the astrometric signature expected in {\it Gaia} DR3 and predict systematically elevated {\tt RUWE} values for nearby LSPs. In contrast, the observed {\tt RUWE} o
Large language models (LLMs) excel at natural language reasoning but remain unreliable on tasks requiring strict rule adherence, determinism, and auditability. Logic Sketch Prompting (LSP) is a lightweight prompting framework that introduces typed variables, deterministic condition evaluators, and a rule based validator that produces traceable and repeatable outputs. Using two pharmacologic logic compliance tasks, we benchmark LSP against zero shot prompting, chain of thought prompting, and concise prompting across three open weight models: Gemma 2, Mistral, and Llama 3. Across both tasks and all models, LSP consistently achieves the highest accuracy (0.83 to 0.89) and F1 score (0.83 to 0.89), substantially outperforming zero shot prompting (0.24 to 0.60), concise prompts (0.16 to 0.30), and chain of thought prompting (0.56 to 0.75). McNemar tests show statistically significant gains for LSP across nearly all comparisons (p < 0.01). These results demonstrate that LSP improves determinism, interpretability, and consistency without sacrificing performance, supporting its use in clinical, regulated, and safety critical decision support systems.
We analyse relevant signals expected at the LHC, assuming that the gluino is the lightest supersymmetric particle (LSP) in the framework of the $μν$SSM. In this $R$-parity violating model, the presence of couplings involving right-handed neutrinos solves simultaneously the $μ$ problem and the accommodations of neutrino masses and mixing angles. We study gluino pair production in quark-antiquark and gluon-gluon collisions. The main decay channels for the gluino LSP are the three-body decays to two quarks and a lepton or a neutrino. In both cases, the leading channels occur for the third family of quarks. We compare the predictions of this scenario with LHC searches for prompt and long-lived particles. To analyse the parameter space we sample the $μν$SSM for a gluino LSP, paying special attention to reproduce the current experimental data on neutrino and Higgs physics, as well as flavour observables. Our results imply a lower limit on the mass of the gluino LSP of about 2600 GeV, and an upper limit for the decay length of about 6 cm.
We analyse relevant signals expected at the LHC for a squark of the first two families as the lightest supersymmetric particle (LSP). The discussion is established in the framework of the $μν$SSM, where the presence of $R$-parity violating couplings involving right-handed neutrinos solves simultaneously the $μ$-problem and the accommodation of neutrino masses and mixing angles. The squarks are pair produced and decay dominantly to a neutrino and a quark. They also have two sub-dominant three body decays to quark, Higgs and neutrino/charged lepton. The decays can be prompt or displaced, depending on the regions of the parameter space of the model. We focus the analyses on squarks of right up-type, right down-type, and left up-type; since squarks of left down-type cannot be the LSP because of D-term contributions. We compare the predictions of these scenarios with ATLAS and CMS searches for prompt and long-lived particles. To analyse the parameter space we sample the $μν$SSM for a squark LSP, paying special attention to reproduce the current experimental data on neutrino and Higgs physics, as well as flavour observables. Because of the contribution of squark-squark final states to th
We briefly review the phenomenon of long secondary periods (LSPs) in red giants, and the LSP variable stars classification introduced in the All-Sky Automated Survey for Supernovae (ASAS-SN) variable star catalog; they are red giant Long Period Variables (LPVs) in which their LSP variability is significantly greater than their pulsational variability. We then describe and discuss the results of a period and amplitude analysis of a random sample of 35 LSP variables in the ASAS-SN catalog, using ASAS-SN data and the AAVSO VStar time-series analysis software. The pulsation period and amplitude, and LSP, all increase with increasing luminosity or size of the star, as expected. The behavior of the LSP amplitude is more complicated; it appears to be larger in moderate-luminosity stars, and smaller in low- and high-luminosity stars. In particular, it is relatively small in a sample of 27 Mira stars, analyzed separately using AAVSO visual data. These results are discussed in the context of the current model for the LSP phenomenon, namely that it is caused by eclipses of the red giant star by a dust-enshrouded companion.
Assuming that the sbottom is the lightest supersymmetric particle (LSP), we carry out an analysis of the relevant signals expected at the LHC. The discussion is established in the framework of the $μν$SSM, where the presence of $R$-parity violating couplings involving right-handed neutrinos solves simultaneously the $μ$-problem and the accommodation of neutrino masses and mixing angles. The sbottoms are pair produced at the LHC, decaying to a lepton and a top quark or a neutrino and a bottom quark. The decays can be prompt or displaced, depending on the regions of the parameter space of the model. We focus the analysis on the right sbottom LSP, since the left sbottom is typically heavier than the left stop because of the D-term contribution. We compare the predictions of this scenario with ATLAS and CMS searches for prompt and long-lived particles. To analyze the parameter space we sample the $μν$SSM for a right sbottom LSP, paying special attention to reproduce the current experimental data on neutrino and Higgs physics, as well as flavor observables. For displaced (prompt) decays, our results translate into lower limits on the mass of the right sbottom LSP of about $1041$ GeV ($1