Rosy Apple Aphid

NYS IPM Type: Fruits IPM Fact SheetThe rosy apple aphid (RAA) can be found throughout the apple growing regions of North America. In the spring, the aphids feed on apple leaves and fruits, and in the summer move to alternate hosts, such as narrow-leaved plantain. The RAA will attack all apple varieties, but varieties such as Cortland, Monroe, Rhode Island Greening, Ida Red, and Golden Delicious are particularly susceptible

Control of Glycolytic Flux by AMPK and p53-mediated Signaling Pathways in Tumor Cells Grown at Low pH

Introduction: Tumor cells grow in nutrient and oxygen deprived microenvironments and adapt to the suboptimal growth conditions by altering metabolic pathways. This adaptation process characteristically results in a tumor phenotype that displays upregulated Hif-1α anaerobic glycolysis, chronic acidification, reduced rate of overall protein synthesis, lower rate of cell proliferation and aggressive invasive characteristics. Most transplantable tumors exhibit a pHe of 6.7- 7.0; the DB-1 melanoma xenografts used here have a pHe=6.7. Understanding tumor cell reaction to the microenvironment is a critical factor in predicting the tumor response to radiotherapy. The glucose regulatory molecule, 6-Phosphofructo-2-Kinase/Fructose-2,6- Biphosphatase Isoform-3 (PFKFB3), is a bifunctional enzyme central to glycolytic flux and downstream of the metabolic stress sensor AMP-activated protein kinase (AMPK), which we show activates an isoform of phosphofructokinase (PFK-2). Radiation Research Society (RRS) 8th Annual Meeting September 25-29, Maui, H

Control of Glycolytic Flux by AMPK and p53-Mediated Signaling Pathways in Tumor Cells Adapted to Grow at Low pH

Introduction: Tumor cells grow in nutrient and oxygen deprived microenvironments and adapt to the suboptimal growth conditions by altering metabolic pathways. This adaptation process characteristically results in a tumor phenotype that displays anaerobic glycolysis, chronic acidification and aggressive tumor characteristics. Understanding the tumor cell reaction to the microenvironment is a critical factor in predicting the tumor response to hyperthermia. The glucose regulatory molecule, 6-Phosphofructo-2-Kinase/Fructose-2,6-Biphosphatase Isoform-3 (PFKFB3), is a bifunctional enzyme central to glycolytic flux and downstream of the metabolic stress sensor AMP-activated protein kinase (AMPK), which has been shown to activate an isoform of Phosphofructokinase (PFK-2). Society for Thermal Medicine Annual Meeting April 23-26, Clearwater Beach, FL

Hot dense capsule implosion cores produced by z-pinch dynamic hohlraum radiation

Hot dense capsule implosions driven by z-pinch x-rays have been measured for the first time. A ~220 eV dynamic hohlraum imploded 1.7-2.1 mm diameter gas-filled CH capsules which absorbed up to ~20 kJ of x-rays. Argon tracer atom spectra were used to measure the Te~ 1keV electron temperature and the ne ~ 1-4 x10^23 cm-3 electron density. Spectra from multiple directions provide core symmetry estimates. Computer simulations agree well with the peak compression values of Te, ne, and symmetry, indicating reasonable understanding of the hohlraum and implosion physics.Comment: submitted to Phys. Rev. Let

In vitro transactivation of Bacillus subtilis RNase P RNA

AbstractDeletion of the ‘signature’ PL5.1 stem-loop structure of a Type II RNase P RNA diminished its catalytic activity. Addition of PL5.1 in trans increased catalytic efficiency (kcat/KM) rather than kcat. Transactivation was due to the binding of a single PL5.1 species per ribozyme with an apparent Kd near 600 nM. The results are consistent with the role of PL5.1 being to position the substrate near the active site of the ribozyme, and with the hypothesis that ribozymes can evolve by accretion of preformed smaller structures

Target diagnostics for intense lithium ion hohlraum experiments on PBFA II

A review of the diagnostics used at Sandia National Laboratories to measure the parameters of intense lithium ion-beam hohlraum target experiments on PBFA II will be presented. This diagnostic package contains an extensive suite of x-ray spectral and imaging diagnostics that enable measurements of target temperature and x-ray output. The x-ray diagnostics include time-integrated and time-resolved pinhole cameras, energy-resolved I-D streaked imaging, diagnostics, time-integrated and time-resolved grazing, incidence spectrographs, a transmission grating spectrograph, an elliptical crystal spectrograph, a bolometer array, an eleven-element x-ray diode (XRD) array, and an eleven-element PIN diode detector array. The incident Li beam symmetry and an estimate of incident Li beam power density can be measured from ion beam-induced characteristic x-ray line emission and neutron emission

The derivation of the formyl-group oxygen of chlorophyll b in higher plants from molecular oxygen.

The mechanism of formation of the formyl group of chlorophyll b has long been obscure but, in this paper, the origin of the 7-formyl-group oxygen of chlorophyll b in higher plants was determined by greening etiolated maize leaves, excised from dark-grown plants, by illumination under white light in the presence of either H218O or 18O2 and examining the newly synthesized chlorophylls by mass spectroscopy. To minimize the possible loss of 18O label from the 7-formyl substituent by reversible formation of chlorophyll b-71-gem-diol (hydrate) with unlabelled water in the cell, the formyl group was reduced to a hydroxymethyl group during extraction with methanol containing NaBH4: chlorophyll a remained unchanged during this rapid reductive extraction process. Mass spectra of chlorophyll a and [7-hydroxymethyl]-chlorophyll b extracted from leaves greened in the presence of either H218O or 18O2 revealed that 18O was incorporated only from molecular oxygen but into both chlorophylls: the mass spectra were consistent with molecular oxygen providing an oxygen atom not only for incorporation into the 7-formyl group of chlorophyll b but also for the well-documented incorporation into the 131-oxo group of both chlorophylls a and b [see Walker, C. J., Mansfield, K. E., Smith, K. M. & Castelfranco, P. A. (1989) Biochem. J. 257, 599–602]. The incorporation of isotope led to as much as 77% enrichment of the 131-oxo group of chlorophyll a: assuming identical incorporation into the 131 oxygen of chlorophyll b, then enrichment of the 7-formyl oxygen was as much as 93%. Isotope dilution by re-incorporation of photosynthetically produced oxygen from unlabelled water was negligible as shown by a greening experiment in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea. The high enrichment using 18O2, and the absence of labelling by H218O, unequivocally demonstrates that molecular oxygen is the sole precursor of the 7-formyl oxygen of chlorophyll b in higher plants and strongly suggests a single pathway for the formation of the chlorophyll b formyl group involving the participation of an oxygenase-type enzyme

Degeneracy of consistency equations in braneworld inflation

In a Randall-Sundrum type II inflationary scenario we compute perturbation amplitudes and spectral indices up to next-to-lowest order in the slow-roll parameters, starting from the well-known lowest-order result for a de Sitter brane. Using two different prescriptions for the tensor amplitude, we show that the braneworld consistency equations are not degenerate with respect to the standard relations and we explore their observational consequences. It is then shown that, while the degeneracy between high- and low-energy regimes can come from suitable values of the cosmological observables, exact functional matching between consistency expressions is plausibly discarded. This result is then extended to the Gauss-Bonnet case.Comment: 16 pages, 3 figures. v3: major revision. Changed title, updated references, rearranged material, new prescription for the tensor spectrum, new figures, extended and more robust conclusion

Unexpected enzyme-catalysed [4+2] cycloaddition and rearrangement in polyether antibiotic biosynthesis

Enzymes that catalyse remarkable Diels–Alder-like [4+2] cyclizations have been previously implicated in the biosynthesis of spirotetronate and spirotetramate antibiotics. Biosynthesis of the polyether antibiotic tetronasin is not expected to require such steps, yet the tetronasin gene cluster encodes enzymes Tsn11 and Tsn15, which are homologous to authentic [4+2] cyclases. Here, we show that deletion of Tsn11 led to accumulation of a late-stage intermediate, in which the two central rings of tetronasin and four of its twelve asymmetric centres remain unformed. In vitro reconstitution showed that Tsn11 catalyses an apparent inverse-electron-demand hetero-Diels–Alder-like [4+2] cyclization of this species to form an unexpected oxadecalin compound that is then rearranged by Tsn15 to form tetronasin. To gain structural and mechanistic insight into the activity of Tsn15, the crystal structure of a Tsn15-substrate complex has been solved at 1.7 Å resolution

Holography and Brane-bulk Energy Exchange

The five-dimensional description of generalized Randall-Sundrum cosmology is mapped via holography to a generalization of the Starobinsky model. This provides a holographic dual description of the cosmological brane-bulk energy exchange processes studied previously. Some simple solutions are presented in four dimensions.Comment: 41 pages, LaTe