Transition from conventional farming to organic farming using bahiagrass

The necessity of ecologically friendly farming systems coupled with the desire for foods free from synthetic chemicals has made organic farming one of the fastest‐growing agricultural enterprises. The transition from conventional agriculture to organic farming is a difficult period for several reasons, (1) since it occurs at a time of least experience for the growers getting into organic farming, (2) because predator–prey links are not fully developed, (3) because farmers usually do not receive a full premium for their products and (4) because initial yields may be low. Transitioning from conventional to organic farming is at the very least region‐specific and frequently farm‐specific in nature. In the southeastern USA the use of perennial grasses such as bahiagrass (Paspalum notatum Fluegge) has been shown to have several benefits that may be useful in the transition process. Bahiagrass improves soil health by reducing erosion, increasing soil organic matter, recovering and conserving plant nutrients and promoting good soil structure. Furthermore, since bahiagrass is a non‐host to most soil‐borne pathogens, it reduces disease and nematode infestations. The resultant increase in soil organic matter from bahiagrass increases the abundance of beneficial organisms, which enables the new system to reach equilibrium quickly. Leguminous cover crops grown during the winter dormancy of bahiagrass provide the necessary nitrogen during the transitional stage. Cover crops also reduce weed emergence and improve soil structure and water retention. Copyright © 2007 Society of Chemical Industry     

Digital and analog signal applications of operational amplifiers II?Sample/hold modules, peak detectors, and comparators

There are two basic types of sample/hold circuits? inverting and noninverting?and two important parameters for these circuits?aperture time and acquisition time. Peak detectors are special forms of sample/hold modules in which the peak value of an input signal, once reached, is automatically held. The last networks discussed in this article are comparators, in which one or more summing resistors are connected to the inverting output of the operational amplifier.     

VGE-CUGrid: An integrated platform for efficient configuration,computation, and visualization of MM5

The platform of VGE-CUGrid integrates a computational grid (CUGrid) and a virtual geographic environment (VGE) to enable an efficient life-cycle process of MM5. The CUGrid is used to speed up MM5 computation. The VGE, which is supported by an underlying GIS system and virtual reality, is adopted as the friendly and efficient interface for initiation, computation, and visualization and analysis of MM5.     

On the Use of Surface Plasmon Resonance Biosensing to Understand IgG-FcγR Interactions

Surface plasmon resonance (SPR)-based optical biosensors offer real-time and label-free analysis of protein interactions, which has extensively contributed to the discovery and development of therapeutic monoclonal antibodies (mAbs). As the biopharmaceutical market for these biologics and their biosimilars is rapidly growing, the role of SPR biosensors in drug discovery and quality assessment is becoming increasingly prominent. One of the critical quality attributes of mAbs is the N-glycosylation of their Fc region. Other than providing stability to the antibody, the Fc N-glycosylation influences immunoglobulin G (IgG) interactions with the Fcγ receptors (FcγRs), modulating the immune response. Over the past two decades, several studies have relied on SPR-based assays to characterize the influence of N-glycosylation upon the IgG-FcγR interactions. While these studies have unveiled key information, many conclusions are still debated in the literature. These discrepancies can be, in part, attributed to the design of the reported SPR-based assays as well as the methodology applied to SPR data analysis. In fact, the SPR biosensor best practices have evolved over the years, and several biases have been pointed out in the development of experimental SPR protocols. In parallel, newly developed algorithms and data analysis methods now allow taking into consideration complex biomolecular kinetics. In this review, we detail the use of different SPR biosensing approaches for characterizing the IgG-FcγR interactions, highlighting their merit and inherent experimental complexity. Furthermore, we review the latest SPR-derived conclusions on the influence of the N-glycosylation upon the IgG-FcγR interactions and underline the differences and similarities across the literature. Finally, we explore new avenues taking advantage of novel computational analysis of SPR results as well as the latest strategies to control the glycoprofile of mAbs during production, which could lead to a better understanding and modelling of the IgG-FcγRs interactions.     

Photoreaction of aromatic compounds at alpha-FeOOH/H2O interface in the presence of H2O2: evidence for organic-goethite surface complex formation

The photoreactions of aromatic compounds were investigated in aqueous dispersions of alpha-FeOOH(goethite)/H(2)O(2) at neutral pHs. It was found that aromatic compounds could undergo rapid decomposition and mineralization (even to 100% yield) in the presence of both alpha-FeOOH and H(2)O(2) under UV irradiation, and the degradation rates of the organics were related to their sorption ability of the surface of alpha-FeOOH and were in the following order: salicylic acid approximately m-hydroxylbenzoic acid>p-hydroxylbenzoic acid approximately benzoic acid>p-biphthalic acid>phenol>benzenesulfonic acid. The interactions of salicylic acid and benzenesulfonic acid with goethite were examined by Fourier transform infrared spectroscopy (FTIR), and electron spin resonance (ESR) was applied to detect the intermediate radicals formed in the photoreaction. The effect of pH and foreign ligands on the degradation of salicylic acid, decomposition of H(2)O(2), and formation of dissolved iron was also examined.