The role of leadership in salespeople’s price negotiation behavior

Salespeople assume a key role in defending firms’ price levels in price negotiations with customers. The degree to which salespeople defend prices should critically depend upon their leaders’ influence. However, the influence of leadership on salespeople’s price defense behavior is barely understood, conceptually or empirically. Therefore, building on social learning theory, the authors propose that salespeople might adopt their leaders’ price defense behavior given a transformational leadership style. Furthermore, drawing on the contingency leadership perspective, the authors argue that this adoption fundamentally depends on three variables deduced from the motivation–ability–opportunity (MAO) framework, that is, salespeople’s learning motivation, negotiation efficacy, and perceived customer lenience. Results of a multi-level model using data from 92 salespeople and 264 salesperson–customer interactions confirm these predictions. The first to explore contingencies of salespeople’s adoption of their transformational leaders’ price negotiation behaviors, this study extends marketing theory and provides actionable guidance to practitioners

Existence Conditions for Bounded Solutions of Weakly Perturbed Linear Impulsive Systems

The weakly perturbed linear nonhomogeneous impulsive systems in the formẋ A t x εA 1 t x f t , t ∈ R, t / ∈ T : {τ i } Z , Δx| t τi γ i εA 1i x τ i − , τ i ∈ T ⊂ R, γ i ∈ R n , and i ∈ Z are considered. Under the assumption that the generating system for ε 0 does not have solutions bounded on the entire real axis for some nonhomogeneities and using the VishikLyusternik method, we establish conditions for the existence of solutions of these systems bounded on the entire real axis in the form of a Laurent series in powers of small parameter ε with finitely many terms with negative powers of ε, and we suggest an algorithm of construction of these solutions

Existence Conditions for Bounded Solutions of Weakly Perturbed Linear Impulsive Systems

The weakly perturbed linear nonhomogeneous impulsive systems in the form ẋ=A(t)x  +  εA1(t)x  +  f(t),  t∈R,  t∉T:={τi}Z, Δx|t=τi=γi+εA1ix(τi-),  τi∈T⊂R,  γi∈Rn, and i∈Z are considered. Under the assumption that the generating system (for ε=0) does not have solutions bounded on the entire real axis for some nonhomogeneities and using the Vishik-Lyusternik method, we establish conditions for the existence of solutions of these systems bounded on the entire real axis in the form of a Laurent series in powers of small parameter ε with finitely many terms with negative powers of ε, and we suggest an algorithm of construction of these solutions

Perturbed Fredholm boundary value problems for delay differential systems

Boundary value problems for systems of ordinary differential equations with a small parameter ε and with a finite number of measurable delays of the argument are considered. Under the assumption that the number m of boundary conditions does not exceed the dimension n of the differential system, it is proved that the point ε=0 generates ρ-parametric families (where ρ=n−m) of solutions of the initial problem. Bifurcation conditions of such solutions are established. Also, it is shown that the index of the operator, which is determined by the initial boundary value problem, is equal to ρ and coincides with the index of the unperturbed problem. Finally, an algorithm for construction of solutions (in the form of Laurent series with a finite number terms of negative power of ε) of the boundary value problem under consideration is suggested

Human Endothelial Cells Enhance Human Immunodeficiency Virus Type 1 Replication in CD4(+) T Cells in a Nef-Dependent Manner In Vitro and In Vivo

Infected CD4(+) T cells are the primary sites of human immunodeficiency virus type 1 (HIV-1) replication in vivo. However, signals from professional antigen-presenting cells (APCs), such as dendritic cells and macrophages, greatly enhance HIV-1 replication in T cells. Here, we report that in cocultures, vascular endothelial cells (ECs), which in humans can also serve as APCs, can enhance HIV-1 production of both CCR5- and CXCR4-utilizing strains approximately 50,000-fold. The observed HIV-1 replication enhancement conferred by ECs occurred only in memory CD4(+) T cells, required expression of major histocompatibility complex class II (MHC-II) molecules by the ECs, and could not be conferred by fixed ECs, all of which are consistent with a requirement for EC-mediated T-cell activation via T-cell receptor (TCR) signaling. Deletion of nef (Nef(−)) decreased HIV-1 production by approximately 100-fold in T cells cocultured with ECs but had no effect on virus production in T cells cocultured with professional APCs or fibroblasts induced to express MHC-II. Human ECs do not express B7 costimulators, but Nef(−) replication in CD4(+)-T-cell and EC cocultures could not be rescued by anti-CD28 antibody. ECs act in trans to enhance wild-type but not Nef(−) replication and facilitate enhanced wild-type replication in naïve T cells when added to T-cell or B-lymphoblastoid cell cocultures, suggesting that ECs also provide a TCR-independent signal to infected T cells. Consistent with these in vitro observations, wild-type HIV-1 replicated 30- to 50-fold more than Nef(−) in human T cells infiltrating allogeneic human skin grafts on human huPBL-SCID/bg mice, an in vivo model of T-cell activation by ECs. Our studies suggest that ECs, which line the entire cardiovascular system and are, per force, in frequent contact with memory CD4(+) T cells, provide signals to HIV-1-infected CD4(+) T cells to greatly enhance HIV-1 production in a Nef-dependent manner, a mechanism that could contribute to the development of AIDS

2-APCAs, the Novel Microtubule Targeting Agents Active against Distinct Cancer Cell Lines

Microtubules are known as the most attractive molecular targets for anti-cancer drugs. However, the number of serious limitations of the microtubule targeting agents (MTAs) including poor bioavailability, adverse effects (e.g., systemic and neural toxicity), and acquired resistance after initiation of MTA-based therapy remain the driving forces to develop the novel therapeutic agents effectively targeting microtubules and exhibiting potent anti-tumor activities. Here, we report the discovery of 2-amino-pyrrole-carboxamides (2-APCAs), a novel class of MTA, which effectively inhibited the growth of the broad spectrum of cancer cell lines in vitro, including various types of breast, prostate, and non-small lung cancer (NSLC), soft tissue sarcomas (STS) (e.g., leio-, rhabdomyo-, and fibrosarcomas), osteosarcomas and gastrointestinal stromal tumors (GISTs). Importantly, 2-APCAs were also effective in cancer cell lines exhibiting resistance to certain chemotherapeutic agents, including MTAs and topoisomerase II inhibitors. The anti-proliferative effect of 2-APCAs was due to their ability to interfere with the polymerization of tubulin and thereby leading to the accumulation of tumor cells in the M-phase. As an outcome of the mitotic arrest, cancer cells underwent apoptotic cell death which was evidenced by increased expression of cleaved forms of the poly-ADP-ribose polymerase (PARP) and caspase-3 and the increased numbers of Annexin V-positive cells, as well. Among the compounds exhibiting the potent anti-cancer activities against the various cancer cell lines indicated above, 2-APCA-III was found the most active. Importantly, its cytotoxic activities correlated with its highest potency to interfere with the dynamics of tubulin polymerization and inducement of cell cycle arrest in the G2/M phase. Interestingly, the cytotoxic and tubulin polymerization activities of 2-APCAs correlated with the stability of the «tubulin—2-АРСА» complexes, illustrating the “tubulin-2-APCA-III” complex as the most stable. Molecular docking showed that the binding site for 2-АРСА-III is located in α tubulin by forming a hydrogen bond with Leu23. Of note, single-cell electrophoresis (Comet assay) data illustrated the low genotoxic activities of 2-APCAs when compared to certain anti-cancer chemotherapeutic agents. Taken together, our study describes the novel MTAs with potent anti-proliferative and pro-apoptotic activities, thereby illustrating them as a scaffold for the development of successful chemotherapeutic anti-cancer agent targeting microtubules