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Diverse Spectrum (diverse + spectrum)
Selected AbstractsEvolving the UPS brandDESIGN MANAGEMENT REVIEW, Issue 2 2004Larry Bloomenkranz When it was designed in 1961, the corporate identity was a compelling symbol for UPS. In the intervening decades, however, things had changed,dramatically! The company was significantly larger, a leader in a diverse spectrum of interrelated businesses, and publicly traded. In this context, Larry Bloomenkranz details the rationale, the research, and the meaning of the company's most recent brand developments. [source] Ant versus bird exclusion effects on the arthropod assemblage of an organic citrus groveECOLOGICAL ENTOMOLOGY, Issue 3 2010JOSEP PIÑOL 1. Predation-exclusion experiments have highlighted that top-down control is pervasive in terrestrial communities, but most of these experiments are simplistic in that they only excluded a single group of predators and the effect of removal was evaluated on a few species from the community. The main goal of our study was to experimentally establish the relative effects of ants and birds on the same arthropod assemblage of canopy trees. 2. We conducted 1-year long manipulative experiments in an organic citrus grove intended to quantify the independent effects of bird and ant predators on the abundance of arthropods. Birds were excluded with plastic nets whereas ants were excluded with sticky barriers on the trunks. The sticky barrier also excluded other ground dwelling insects, like the European earwig Forficula auricularia L. 3. Both the exclusion of ants and birds affected the arthropod community of the citrus canopies, but the exclusion of ants was far more important than the exclusion of birds. Indeed, almost all groups of arthropods had higher abundance in ant-excluded than in control trees, whereas only dermapterans were more abundant in bird-excluded than in control trees. A more detailed analysis conducted on spiders also showed that the effect of ant exclusion was limited to a few families rather than being widespread over the entire diverse spectrum of spiders. 4. Our results suggest that the relative importance of vertebrate and invertebrate predators in regulating arthropod populations largely depends on the nature of the predator,prey system. [source] Prey availability directly affects physiology, growth, nutrient allocation and scaling relationships among leaf traits in 10 carnivorous plant speciesJOURNAL OF ECOLOGY, Issue 1 2008Elizabeth J. Farnsworth Summary 1Scaling relationships among photosynthetic rates, leaf mass per unit area (LMA), and foliar nitrogen (N) and phosphorus (P) content hold across a diverse spectrum of plant species. Carnivorous plants depart from this spectrum because they dedicate substantial leaf area to capturing prey, from which they derive N and P. We conducted a manipulative feeding experiment to test whether scaling relationships of carnivorous plant leaf traits become more similar to those of non-carnivorous taxa when nutrients are not limiting. 2We examined the effects of prey availability on mass-based maximum photosynthetic rate (Amass), chlorophyll fluorescence, foliar nutrient and chlorophyll content, and relative growth rate of 10 Sarracenia species. We hypothesized that increased prey intake would stimulate Amass, reduce stress-related chlorophyll fluorescence, increase photosynthetic nutrient-use efficiencies (PNUEN, PNUEP), and increase relative biomass allocation to photosynthetically efficient, non-carnivorous phyllodes. 3Two plants per species were assigned in a regression design to one of six weekly feedings of finely ground wasps: 0,0.25 g for small plant species; 0,0.5 g for intermediate-sized species; and 0,1.0 g for large species. The first two leaves emerging on each plant were fed. 4Increased prey availability increased photosystem efficiency (Fv/Fm ratio) in the first two leaves, and chlorophyll content and Amass in younger leaves as older leaves rapidly translocated nutrients to growing tissues. Higher prey inputs also led to lower N : P ratios and a shift from P- to N-limitation in younger leaves. PNUEP was significantly enhanced whilst PNUEN was not. Better-fed plants grew faster and produced a significantly higher proportion of phyllodes than controls. 5Feeding shifted scaling relationships of P relative to Amass, N and LMA from outside the third bivariate quartile to within the 50th bivariate percentile of the universal spectrum of leaf traits; other scaling relationships were unaffected. Carnivorous plants can rapidly reallocate P when nutrients are plentiful, but appear to be less flexible in terms of N allocation. 6Synthesis. Our results support the general hypothesis put forward by Shipley et al. (2006) that observed scaling relationships amongst leaf traits derive from trade-offs in allocation to structural tissues vs. liquid-phase (e.g. photosynthetic) processes. These trade-offs appear to be especially constraining for plants growing in extremely nutrient-poor habitats such as bogs and other wetlands. [source] Group A Streptococcus causing a life-threatening postpartum necrotizing myometritis: A case reportJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 4pt2 2008Samuel Lurie Abstract During childbirth, group A Streptococcus (GAS) can cause a diverse spectrum of disorders ranging from asymptomatic infection to puerperal sepsis and toxic shock syndrome. We report on a healthy parturient who survived a life-threatening necrotizing myometritis due to GAS following an unremarkable spontaneous delivery. Approximately 29 h after an unremarkable spontaneous vaginal delivery, a generally healthy 28-year-old multiparous woman developed a life-threatening necrotizing myometritis due to GAS. The patient subsequently underwent a total abdominal hysterectomy. Following the surgery, she made a prompt and complete recovery. The course of this extremely rare complication might be so fulminant that the diagnosis is sometimes made after the patient cannot be saved. Clinicians should still consider GAS in life-threatening infections occurring during the perinatal period. [source] Malignant solitary fibrous tumor arising from the pineal region: case study and literature reviewNEUROPATHOLOGY, Issue 3 2010Jing Zhang We report a case of malignant solitary fibrous tumor involving the pineal region in a 49-year-old woman. The patient presented with headache, slowly progressive weakness of the right lower extremities and upgaze palsy over the past year. Histologically, the tumor was composed of moderately hypercellular proliferated spindle cells with eosinophilic collagen bands. These cells were diffusely and strongly immunoreactive with CD34, CD99, and vimentin, but were negative with epithelial membrane antigen, S-100 protein, Bcl-2, smooth muscle actin, cytokeratin and glial fibrillary antigenic protein. MIB-1 labeling indices and mitosis rates were 7.3 ± 1.8% and 5 per 10 high power fields, respectively. Ultrastructural examination revealed that the neoplastic cells had features of fibroblastic differentiation. Differential diagnoses included fibrous meningioma and hemangiopericytoma. The present case provides one unique example of a rare entity to the already diverse spectrum of the pineal region neoplasms encountered in neuropathology. [source] Cryptococcosis in ferrets: a diverse spectrum of clinical diseaseAUSTRALIAN VETERINARY JOURNAL, Issue 12 2002R MALIK Cryptococcosis was diagnosed in seven ferrets (five from Australia; two from western Canada) displaying a wide range of clinical signs. Two of the ferrets lived together. One (5-years-old) had cryptococcal rhinitis and presented when the infection spread to the nasal bridge. Its sibling developed cryptococcal abscessation of the right retropharyngeal lymph node 12 months later, soon after developing a severe skin condition. DNA fingerprinting and microsatellite analysis demonstrated that the two strains isolated from these siblings were indistinguishable. Two ferrets (2- to 3-years-old) developed generalised cryptococcosis: one had primary lower respiratory tract disease with pneumonia, pleurisy and medi-astinal lymph node involvement, while in the other a segment of intestine was the primary focus of infection with subsequent spread to mesenteric lymph nodes, liver and lung. The remaining three ferrets (1.75 to 4-years-old) had localised disease of a distal limb, in one case with spread to the regional lymph node. Cryptococcus bacillisporus(formerly C neoformansvar gattii) accounted for three of the four infections in Australian ferrets where the biotype could be determined. The Australian ferret with intestinal involvement and the two ferrets from Vancouver had C neoformansvar grubiiinfections. [source] Parsing the Effects of Binding, Signaling, and Trafficking on the Mitogenic Potencies of Granulocyte Colony-Stimulating Factor AnaloguesBIOTECHNOLOGY PROGRESS, Issue 3 2003Casim A. Sarkar The pharmacodynamic potency of a therapeutic cytokine interacting with a cell-surface receptor can be attributed primarily to three central properties: [1] cytokine/receptor binding affinity, [2] cytokine/receptor endocytic trafficking dynamics, and [3] cytokine/receptor signaling. Thus, engineering novel or second-generation cytokines requires an understanding of the contribution of each of these to the overall cell response. We describe here an efficient method toward this goal in demonstrated application to the clinically important cytokine granulocyte colony-stimulating factor (GCSF) with a chemical analogue and a number of genetic mutants. Using a combination of simple receptor-binding and dose-response proliferation assays we construct an appropriately scaled plot of relative mitogenic potency versus ligand concentration normalized by binding affinity. Analysis of binding and proliferation data in this manner conveniently indicates which of the cytokine properties,binding, trafficking, and/or signaling,are contributing substantially to altered potency effects. For the GCSF analogues studied here, two point mutations as well as a poly(ethylene glycol) chemical conjugate were found to have increased potencies despite comparable or slightly lower affinities, and trafficking was predicted to be the responsible mechanism. A third point mutant exhibiting comparable binding affinity but reduced potency was predicted to have largely unchanged trafficking properties. Surprisingly, another mutant possessing an order-of-magnitude weaker binding affinity displayed enhanced potency, and increased ligand half-life was predicted to be responsible for this net beneficial effect. Each of these predictions was successfully demonstrated by subsequent measurements of depletion of these five analogues from cell culture medium. Thus, for the GCSF system we find that ligand trafficking dynamics can play a major role in regulating mitogenic potency. Our results demonstrate that cytokine analogues can exhibit pharmacodynamic behaviors across a diverse spectrum of "binding-potency space" and that our analysis through normalization can efficiently elucidate hypotheses for the underlying mechanisms for further dedicated testing. We have also extended the Black-Leff model of pharmacological agonism to include trafficking effects along with binding and signaling, and this model provides a framework for parsing the effects of these factors on pharmacodynamic potency. [source] | |||||||||||||