Predicted future shifts in the magnitude and frequency (larger but fewer) of precipitation events and enhanced nitrogen (N) deposition may interact to affect grassland productivity, but the effects of N enrichment on the productivity response to individual precipitation events remain unclear. In this study, we quantified the effects of N addition on the response patterns of gross primary produc...

Forskolin activated adenylate cyclase of purified rat adipocyte membranes in the absence of exogenous guanine nucleotides. Guanyl-5”yl imidodiphosphate (Gpp(NH)p) inhibited the forskolin-activated cyclase immediately upon addition of the nucleotide at concentrations too low to activate adenylate cyclase (lo-’ to M). Inhibition seen with a very high concentration of Gpp(NH)p M) lasted for 3-4 m...

We have identified a novel gene named grappa (gpp) that is the Drosophila ortholog of the Saccharomyces cerevisiae gene Dot1, a histone methyltransferase that modifies the lysine (K)79 residue of histone H3. gpp is an essential gene identified in a genetic screen for dominant suppressors of pairing-dependent silencing, a Polycomb-group (Pc-G)-mediated silencing mechanism necessary for the maint...

In this paper, we describe the Geometric Path Planner (GPP) that produces routes for unmanned ground and air vehicles. The GPP generates plans that minimize a weighted, multi-metric cost function considering factors such as mobility risk, traversal time, sensor coverage, and stealth. In addition to cost minimization, the GPP is able to reason about hard constraints imposed on one or more of the...

Geranyl diphosphate (GPP), the precursor of most monoterpenes, is synthesized in plastids from dimethylallyl diphosphate and isopentenyl diphosphate by GPP synthases (GPPSs). In heterodimeric GPPSs, a non-catalytic small subunit (GPPS-SSU) interacts with a catalytic large subunit, such as geranylgeranyl diphosphate synthase, and determines its product specificity. Here, snapdragon (Antirrhinum ...

same extent as M-( -)-propranolol (by 80%). Treatment of membranes with isoprenaline + GMP converts N from the closed GDP-bound state to an open Gpp(NH)presponsive form (Braun et af . , 1982). This form of N was found to be relatively insensitive to propranolol and also attenuated the filipin inhibition of Gpp(NH)p stimulation, but to a lesser extent. The reason for this is unclear, but may be ...

Estimating gross primary production (GPP) and net primary production (NPP) are significant important in studying carbon cycles. Using models driven by multi-source and multi-scale data is a promising approach to estimate GPP and NPP at regional and global scales. With a focus on data that are openly accessible, this paper presents a GPP and NPP model driven by remotely sensed data and meteorolo...

D eveloping a single-processor platform is bad enough. Adding another to the mix could drive even the best developers over the edge, especially when the mix involves a general-purpose processor (GPP) and a DSP. Take heart. A new way of thinking and working allows DSP processes to make operating system calls that are processed by the GPP. Likewise, the operating system running on the GPP can con...

Temporal changes in plant tissue non-structural carbohydrates (NSC) may be sensitive to climate changes that alter forest phenology. We examined how temporal fluctuations in tissue NSC concentrations of Populus grandidentata and Quercus rubra relate to net and gross primary production (NPP, GPP) and their climatic drivers in a deciduous forest of Michigan, USA. Tissue NSC concentrations were co...

Determining the spatial and temporal distribution of terrestrial gross primary production (GPP) is a critical step in closing the Earth’s carbon budget. Dynamical global vegetation models (DGVMs) provide mechanistic insight into GPP variability but diverge in predicting the response to climate in poorly investigated regions. Recent advances in the remote sensing of solar-induced chlorophyll flu...