283 research outputs found
Results from a three year testing project of new strawberry cultivars in Verticillium infested soils and under organic farming conditions
As part of a research project 13 cultivars were planted in 2005 at 11 sites on 9 farms in 5
different Austrian regions. The aim was to find new cultivars tolerant to soil-borne
pathogens and leaf/fruit diseases, with high yield, winter hardness and good fruit quality, to
serve as alternative to the highly susceptible cultivar ‘Elsanta’, regarding soil-borne
diseases. Plant vigour and infestation with Verticillium dahliae and leaf diseases were
evaluated in 2005 und 2006 at 7 sites and in 2007 at 3 sites.
In addition, following parameters were assessed on 2 organically managed sites in 2006
and 2007: marketable yield, percentage of different categories of unmarketable fruits and
incidence of the blossom weevil. In 2006 fruit characteristics and consumer acceptance
were studied.
‘Elsanta’ showed the highest infestation with V. dahliae whereas ‘Salsa’, ‘Daroyal’ and
‘Alice’ were most tolerant. ‘Dora’, ‘Eva’, ‘Queen Elisa’ and ‘Daroyal’ recorded significantly
higher losses by the blossom weevil than ‘Alice’. ‘Alba’ and ‘Divine’ were the earliest
cultivars in ripening time. Highest marketable yield per plant had the late ripening cultivars,
particularly ‘Salsa’ and ‘Sonata’. Of all early ripening cultivars tested, ‘Elsanta’ showed the
highest productivity, followed by 'Alba', ‘Darselect’, ‘Daroyal’ and ‘Eva’. Regarding fruit
firmness, content of ascorbic acid, shelf life and appearance, ‘Alba’, ’Clery’, ‘Eva’ and
‘Queen Elisa’ were most convincing. The best tasting cultivars were ‘Clery’, ‘Daroyal’ and
‘Divine’.
Summing up all the results, ‘Alba’, ‘Alice’ and ‘Salsa’ can be recommended for organic
production, whereas ‘Clery’, ‘Daroyal’, ‘Darselect’, ‘Elsanta’, ‘Eva’, ‘Queen Elisa’ and
‘Sonata’ are classified as suitable for only a limited extent. ‘Elsanta’, ‘Divine’, ‘Dora’ and
‘Sonata’ are particularly unsuitable for growing in Verticillium infested soils. ‘Divine’, ‘Dora’,
and ‘Record’ cannot be recommended for organic production at all
Independent Orbiter Assessment (IOA): Assessment of the landing/deceleration (LDG/DEC) subsystem FMEA/CIL
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Landing/Deceleration (LDG/DEC) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter LDG/DEC hardware. The IOA product for the LDG/DEC analysis consisted of 259 failure mode worksheets that resulted in 124 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 267 FMEA's and 120 CIL items. This comparison produced agreement on all but 75 FMEA's which caused differences in 51 CIL items
Effect of dynamic stall on the aerodynamics of vertical-axis wind turbines
Accurate simulations of the aerodynamic performance of vertical-axis wind turbines pose a significant challenge for computational fluid dynamics methods. The aerodynamic interaction between the blades of the rotor and the wake that is produced by the blades requires a high-fidelity representation of the convection of vorticity within the wake. In addition, the cyclic motion of the blades induces large variations in the angle of attack on the blades that can manifest as dynamic stall. The present paper describes the application of a numerical model that is based on the vorticity transport formulation of the Navier–Stokes equations, to the prediction of the aerodynamics of a verticalaxis wind turbine that consists of three curved rotor blades that are twisted helically around the rotational axis of the rotor. The predicted variation of the power coefficient with tip speed ratio compares very favorably with experimental measurements. It is demonstrated that helical blade twist reduces the oscillation of the power coefficient that is an inherent feature of turbines with non-twisted blade configurations
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Symmetry lowering in crystalline solid solutions: A study of cinnamamide-thienylacrylamide by x-ray and neutron diffraction and solid-state photochemistry
Principles are outlined for symmetry lowering of a mixed crystal. A survey is given of methods used to detect reduced symmetry: changes in crystal morphology, detection of enantiomeric segregation of chiral additives in centrosymmetric'' crystals, generation of second harmonic optical signals, optical birefringence, asymmetric photoreactions in the crystalline state and X-ray and neutron diffraction. The last two methods are applied to mixed crystals of cinnamamide host and thienylacrylamide. Diffraction demonstrated that the mixed crystals are composed of six sectors of reduced symmetry, from monoclinic centrosymmetric P2[sub 1]/c to triclinic P1 in four sectors and possibly Pc in the remaining two. The X-ray diffraction data were not sufficiently accurate for assigning the absolute structures of the PI sectors of anomalous X-ray scattering. Thus, by this method one could not ascertain the absolute orientation of the guest molecules on the surface sites through which they were selectively occluded. This ambiguity was resolved by assignment of the absolute configuration of the chiral heterophotodimers, between host and guest, in enantiomeric excess in the PI sectors, after irradiation with UV light. This leads to the conclusion that the selective occlusion of thienylacrylamide arises from replacement of attractive C-H[pi] (electron) interactions between host molecules by a repulsive sulfur (lone pair electron)[pi](electron) interactions between guest and host at the crystal surfaces
CDK-inhibitor independent cell cycle progression in an experimental haematopoietic stem cell leukaemia despite unaltered Rb-phosphorylation
A CD34-negative haematopoietic progenitor cell line, D064, derived from canine bone marrow stromal cells is able to differentiate into haematopoietic progenitors under the influence of growth factor-mediated signalling. While differentiating, these cells eventually start to express MHC class II molecules (DR homologues) on their surface. The stable transfection of the fibroblast-like wild-type cells with retroviral constructs containing the cDNA for the canine MHC class II DR-genes (DRA and DRB) induces a change in morphology, accelerates cell cycle progression and leads to a loss of anchorage-dependent growth. Transfected cells show features of an immature stem cell leukaemia, such as giant cell formation. In wild-type D064 cells the accumulation of the cyclin-dependent kinase inhibitor (cdki) p27kip-1 induces differentiation, which is dependent upon signalling via the ligand for the tyrosine kinase receptor c-kit (stem cell factor). DR-transfected cells instead apparently grow independently of any growth factor-mediated signals and express high levels of the cdkis p27kip-1 and especially p21waf-1/cip-1, concurrently with accelated cell cycle progression. In contrast to the overexpression of cdkis and despite accelerated cell cycle progression, the expression of the G2/M phase transition kinase p34cdc2 is significantly reduced in DR-transfected and transformed cells as compared to the haematopoietic wild-type cell line D064. This might suggest a possible alternative cell cycle progression pathway in this experimental stem cell leukaemia by by-passing the G0/G1 phase arrest, although retinoblastoma (Rb)-phosphorylation remains unaltered. These results provide evidence that mechanisms normally controlling the cell cycle and early haematopoietic differentiation are disrupted by the constitutive transcription and expression of MHC class II genes (DR) leading to a progression and growth of this experimental stem cell leukaemia independent from cell cycle controlling regulators such as p27 and p21. © 1999 Cancer Research Campaig
a randomized, placebo-controlled phase II AIO trial with serum biomarker program
Background As a multi-targeted anti-angiogenic receptor tyrosine kinase (RTK)
inhibitor sunitinib (SUN) has been established for renal cancer and
gastrointestinal stromal tumors. In advanced refractory esophagogastric cancer
patients, monotherapy with SUN was associated with good tolerability but
limited tumor response. Methods This double-blind, placebo-controlled,
multicenter, phase II clinical trial was conducted to evaluate the efficacy,
safety and tolerability of SUN as an adjunct to second and third-line FOLFIRI
(NCT01020630). Patients were randomized to receive 6-week cycles including
FOLFIRI plus sodium folinate (Na-FOLFIRI) once every two weeks and SUN or
placebo (PL) continuously for four weeks followed by a 2-week rest period. The
primary study endpoint was progression-free survival (PFS). Preplanned serum
analyses of VEGF-A, VEGF-D, VEGFR2 and SDF-1α were performed retrospectively.
Results Overall, 91 patients were randomized, 45 in each group (one patient
withdrew). The main grade ≥3 AEs were neutropenia and leucopenia, observed in
56 %/20 % and 27 %/16 % for FOLFIRI + SUN/FOLFIRI + PL, respectively. Median
PFS was similar, 3.5 vs. 3.3 months (hazard ratio (HR) 1.11, 95 % CI
0.70–1.74, P = 0.66) for FOLFIRI + SUN vs. FOLFIRI + PL, respectively. For
FOLFIRI + SUN, a trend towards longer median overall survival (OS) compared
with placebo was observed (10.4 vs. 8.9 months, HR 0.82, 95 % CI 0.50–1.34,
one-sided P = 0.21). In subgroup serum analyses, significant changes in VEGF-A
(P = 0.017), VEGFR2 (P = 0.012) and VEGF-D (P < 0.001) serum levels were
observed. Conclusions Although sunitinib combined with FOLFIRI did not improve
PFS and response in chemotherapy-resistant gastric cancer, a trend towards
better OS was observed. Further biomarker-driven studies with other anti-
angiogenic RTK inhibitors are warranted. Trial registration This study was
registered prospectively in the NCT Clinical Trials Registry
(ClinicalTrials.gov) under NCT01020630 on November 23, 2009 after approval by
the leading ethics committee of the Medical Association of Rhineland-
Palatinate, Mainz, in coordination with the participating ethics committees
(see Additional file 2) on September 16, 2009
Activation of Innate and Adaptive Immunity by a Recombinant Human Cytomegalovirus Strain Expressing an NKG2D Ligand.
Development of an effective vaccine against human cytomegalovirus (HCMV) is a need of utmost medical importance. Generally, it is believed that a live attenuated vaccine would best provide protective immunity against this tenacious pathogen. Here, we propose a strategy for an HCMV vaccine that aims at the simultaneous activation of innate and adaptive immune responses. An HCMV strain expressing the host ligand ULBP2 for the NKG2D receptor was found to be susceptible to control by natural killer (NK) cells, and preserved the ability to stimulate HCMV-specific T cells. Infection with the ULBP2-expressing HCMV strain caused diminished cell surface levels of MHC class I molecules. While expression of the NKG2D ligand increased the cytolytic activity of NK cells, NKG2D engagement in CD8+ T cells provided co-stimulation and compensated for lower MHC class I expression. Altogether, our data indicate that triggering of both arms of the immune system is a promising approach applicable to the generation of a live attenuated HCMV vaccine
Elevated frequencies of leukemic myeloid and plasmacytoid dendritic cells in acute myeloid leukemia with the FLT3 internal tandem duplication
Some 30% of acute myeloid leukemia (AML) patients display an internal tandem duplication (ITD) mutation in the FMS-like tyrosine kinase 3 (FLT3) gene. FLT3-ITDs are known to drive hematopoietic stem cells towards FLT3 ligand independent growth, but the effects on dendritic cell (DC) differentiation during leukemogenesis are not clear. We compared the frequency of cells with immunophenotype of myeloid DC (mDC: Lin−, HLA-DR+, CD11c+, CD86+) and plasmacytoid DC (pDC: Lin−, HLA-DR+, CD123+, CD86+) in diagnostic samples of 47 FLT3-ITD− and 40 FLT3-ITD+ AML patients. The majority of ITD+ AML samples showed high frequencies of mDCs or pDCs, with significantly decreased HLA-DR expression compared with DCs detectable in ITD− AML samples. Interestingly, mDCs and pDCs sorted out from ITD+ AML samples contained the ITD insert revealing their leukemic origin and, upon ex vivo culture with cytokines, they acquired DC morphology. Notably, mDC/pDCs were detectable concurrently with single lineage mDCs and pDCs in all ITD+ AML (n = 11) and ITD− AML (n = 12) samples analyzed for mixed lineage DCs (Lin−, HLA-DR+, CD11c+, CD123+). ITD+ AML mDCs/pDCs could be only partially activated with CD40L and CpG for production of IFN-α, TNF-α, and IL-1α, which may affect the anti-leukemia immune surveillance in the course of disease progression
Revisiting histories of anti-racist thought and activism
This piece reconsiders histories of anti-racist thought and practice, including the linkages between anti-racisms and other traditions of liberatory thought. We argue that anti-racism should be understood as a strand in radical thought linking internationalism, institutional critique and street activism, in the process interfeeding with other social movements. The traditions of anti-racist thought discussed in this special issue exemplify these cross-cutting influences
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