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.
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.
Purpose – The purpose of this paper is to provide an insight to the outsourcing decision-making through investigating if the old evaluation/selection criteria and methods still fit with current business priorities or not and, therefore, to identify the appropriate criteria and methods to develop a new selection framework. Since the economic recession of 2008, logistics outsourcing decisions have become more prominent to avoid high fixed costs and heavy investment requirements and to achieve competitive advantages. Design/methodology/approach – This is a focused literature review prepared after analyzing 56 articles related to the logistics service provider (LSP) evaluation and selection methods and criteria during 2008-2013. The academic articles are analyzed based on research focus/area, evaluation and selection methodology/methods and evaluation and selection criteria. Then reviewed result is compared with previous literature studies for the periods (1991-2008) to identify any possible shifts. Findings – The review reveals that: several problems in current LSPs literature have been identified; the reviewed papers can be categorized into seven groups, the usage and importance of evaluation and selection criteria fluctuate during different periods; 12 crucial criteria have been identified, increasing the importance of specific selection methods and the integrated models and fuzzy logic in logistics literature. Then, a comprehensive LSPs’ evaluation and selection framework has been developed. Originality/value – To the best of our knowledge, this is the first focused logistics outsourcing study that reviews the 2008-2013 period in detail, comparing results with previous literature studies, identifies current LSPs literature problems/gaps, new trends and shifts in the way that LSPs are evaluated and selected, identifies crucial selection criteria and proposes a new holistic LSPs evaluation and selection framework. In addition, it identifies important issues for future research.
This document describes extensions to Resource Reservation Protocol - Traffic Engineering (RSVP-TE) for the set up of Traffic Engineered (TE) point-to-multipoint (P2MP) Label Switched Paths (LSPs) in Multi- Protocol Label Switching (MPLS) and Generalized MPLS (GMPLS) networks. The solution relies on RSVP-TE without requiring a multicast routing protocol in the Service Provider core. Protocol elements and procedures for this solution are described. There can be various applications for P2MP TE LSPs such as IP multicast. Specification of how such applications will use a P2MP TE LSP is outside the scope of this document. [STANDARDS-TRACK]
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Traffic engineering aims to optimize the utilization of existing network resources for load balance and failure recovery, and these are to be accomplished in a scalable fashion. This paper proposes a traffic engineering scheme using multiple multipoint-to-point (m-t-p) label switched paths (LSP) which can reduce the number of LSP and required labels in links. The scheme consists of m-t-p LSP creation and flow assignment. Routes are first selected, and m-t-p LSP are designed to include them. The m-t-p LSP design problem is formulated as a 0-1 integer programming problem. The flow assignment problem is formulated as a mixed integer programming problem in which maximum link load, i.e., maximum congestion, is minimized. Numerical comparisons with the conventional point-to-point LSP approach show that the m-t-p LSP approach can reduce the number of required LSP and labels. Moreover, numerical comparisons with conventional shortest path fast-based flow assignment show that our flow assignment scheme can reduce maximum link load.
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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.
This document defines RSVP-TE extensions to establish backup label- switched path (LSP) tunnels for local repair of LSP tunnels. These mechanisms enable the re-direction of traffic onto backup LSP tunnels in 10s of milliseconds, in the event of a failure. Two methods are defined here. The one-to-one backup method creates detour LSPs for each protected LSP at each potential point of local repair. The facility backup method creates a bypass tunnel to protect a potential failure point; by taking advantage of MPLS label stacking, this bypass tunnel can protect a set of LSPs that have similar backup constraints. Both methods can be used to protect links and nodes during network failure. The described behavior and extensions to RSVP allow nodes to implement either method or both and to interoperate in a mixed network. [STANDARDS-TRACK]
To improve scalability of Generalized Multi-Protocol Label Switching (GMPLS) it may be useful to aggregate Label Switched Paths (LSPs) by creating a hierarchy of such LSPs. A way to create such a hierarchy is by (a) a Label Switching Router (LSR) creating a Traffic Engineering Label Switched Path (TE LSP), (b) the LSR forming a forwarding adjacency (FA) out of that LSP (by advertising this LSP as a Traffic Engineering (TE) link into the same instance of ISIS/OSPF as the one that was used to create the LSP), (c) allowing other LSRs to use FAs for their path computation, and (d) nesting of LSPs originated by other LSRs into that LSP (by using the label stack construct). This document describes the mechanisms to accomplish this.
Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards " (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice
We analyze relevant signals expected at the LHC for a left sneutrino as the lightest supersymmetric particle (LSP). The discussion is carried out in the “[Formula: see text] from [Formula: see text]” supersymmetric standard model [Formula: see text], where the presence of [Formula: see text]-parity breaking couplings involving right-handed neutrinos solves the [Formula: see text] problem and reproduces neutrino data. The sneutrinos are pair produced via a virtual [Formula: see text], [Formula: see text] or [Formula: see text] in the [Formula: see text] channel. From the prompt decay of a pair of left sneutrinos LSPs of any family, a significant diphoton signal plus missing transverse energy (MET) from neutrinos can be present in the mass range 118–132 GeV, with 13 TeV center-of-mass energy and an integrated luminosity of 100 fb[Formula: see text]. In addition, in the case of a pair of tau left sneutrinos LSPs, given the large value of the tau Yukawa coupling diphoton plus leptons and/or multileptons can appear. We find that the number of expected events for the multilepton signal, together with properly adopted search strategies, is sufficient to give a significant evidence for a sneutrino of mass in the range 130–310 GeV, even with the integrated luminosity of 20 fb[Formula: see text]. In the case of the signal producing diphoton plus leptons, an integrated luminosity of 100 fb[Formula: see text] is needed to give a significant evidence in the mass range 95–145 GeV. Finally, we discuss briefly the presence of displaced vertices and the associated range of masses.
We propose a compact combined system which supports compound spoof surface resonances due to the coupling between spoof surface plasmon polaritons (SPPs) and localized surface plasmons (LSPs). The system is composed of ultrathin metallic spiral structures for discrete LSP resonances and an ultrathin corrugated metallic strip to guide continuous SPP modes. We demonstrate both theoretically and experimentally that the LSP resonances can be efficiently excited and captured by the SPP waveguide, while the SPP transmissions can be judiciously controlled by the LSP structures. The spoof SPP-LSP combined system may find potential applications in sensing and integrated photonic circuitry in the microwave and terahertz frequencies.
Line Spectrum Pair (LSP) was first introduced by Itakura [1,2] as an alternative LPC spectral representations. It was found that this new representation has such interesting properties as (1) all zeros of LSP polynomials are on the unit circle, (2) the corresponding zeros of the symmetric and anti-symmetric LSP polynomials are interlaced, and (3) the reconstructed LPC all-pole filter preserves its minimum phase property if (1) and (2) are kept intact through a quantization procedure. In this paper we prove all these properties via a "phase function." The statistical characteristics of LSP frequencies are investigated by analyzing a speech data base. In addition, we derive an expression for spectral sensitivity with respect to single LSP frequency deviation such that some insight on their quantization effects can be obtained. Results on multi-pulse LPC using LSP for spectral information compression are finally presented.
The systematic study of structures with gold and silver nanoparticles (MeNPs) of various shapes and dielectric functions immobilized onto the silver grating is performed. The structures may serve as double resonance SERS (surface-enhanced Raman spectroscopy) systems with coupling between surface plasmon polariton (SPP) supported by the silver grating and localized surface plasmons (LSPs) excited on the grafted metal nanoparticles (MeNPs). The silver grating supports SPP excitation under the 785 nm wavelength illumination. Spherical silver and gold nanoparticles, triangular silver nanoprisms and gold nanorods are prepared and used with the aim to gradually cover the LSP excitation in the 400–850 nm wavelength range. MeNPs are grafted through the 4,4′-biphenyldithiol (BFDT) linkers. Rhodamine 6G (R6G) molecules are added onto SERS substrates and located above and between the MeNPs. Several wavelengths (470, 532, and 785 nm) are applied to probe the SERS response. Depending on the nanoparticles type and excitation wavelength a significant SERS signal is produced by R6G or BFDT molecules. Properties of the prepared structures are simulated using the Finite-difference time-domain method (FDTD). The measured and simulated SERS data are in reasonable agreement, the measured values being lower than those calculated.
Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards " (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice
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We consider a class of anomaly-mediated supersymmetry breaking models where gauginos acquire masses mostly from anomaly mediation while masses of other superparticles are from Kähler interactions, which are as large as gravitino mass ∼O(10–100)TeV. In this class of models, the neutral wino becomes the lightest superparticle in a wide parameter region. The mass splitting between charged and neutral winos are very small and experimental discovery of such winos is highly non-trivial. We discuss how we should look for wino-induced signals at Large Hadron Collider.