Neural Relax

We present an algorithm for data preprocessing of an associative memory inspired to an electrostatic problem that turns out to have intimate relations with information maximization

Ytterbium divalency and lattice disorder in near-zero thermal expansion YbGaGe

While near-zero thermal expansion (NZTE) in YbGaGe is sensitive to stoichiometry and defect concentration, the NZTE mechanism remains elusive. We present x-ray absorption spectra that show unequivocally that Yb is nearly divalent in YbGaGe and the valence does not change with temperature or with nominally 1% B or 5% C impurities, ruling out a valence-fluctuation mechanism. Moreover, substantial changes occur in the local structure around Yb with B and C inclusion. Together with inelastic neutron scattering measurements, these data indicate a strong tendency for the lattice to disorder, providing a possible explanation for NZTE in YbGaGe.Comment: 4 pages, 4 figure, supplementary inf

Filling and wetting transitions of nematic liquid crystals on sinusoidal substrates

Close to sinusoidal substrates, simple fluids may undergo a filling transition, in which the fluid passes from a dry to a filled state, where the interface remains unbent but bound to the substrate. Increasing the surface field, the interface unbinds and a wetting transition occurs. We show that this double-transition sequence may be strongly modified in the case of ordered fluids, such as nematic liquid crystals. Depending on the preferred orientation of the nematic molecules at the structured substrate and at the isotropic-nematic interface, the filling transition may not exist, and the fluid passes directly from a dry to a complete-wet state, with the interface far from the substrate. More interestingly, in other situations, the complete wetting transition may be prevented, and the fluid passes from a dry to a filled state, and remains in this configuration, with the interface always attached to the substrate, even for very large surface fields. Both transitions are only observed for a same substrate in a narrow range of amplitudes

Supplying Improved Seed to Farmers in Rural Kenya: The Case of Freshco Kenya Ltd.

Freshco, a small producer and distributor of hybrid maize seed and macadamia seedlings, was one of the first private companies to enter the Kenya seed market after its liberalization. Currently, the company produces and markets six high yielding maize varieties that are suited for diverse agro-ecological conditions. Despite the company’s encouraging growth in the local maize seed market, Freshco’s executives recognize the need to scale up operations to stay competitive. The company’s challenge is to recognize business opportunities and customer needs in an environment susceptible to ecological, political, and socioeconomic change.Kenya, seed industry, smallholder farmers, scenario planning, Crop Production/Industries, Farm Management, Research Methods/ Statistical Methods, Q10, Q12,

Role of Light Vector Mesons in the Heavy Particle Chiral Lagrangian

We give the general framework for adding "light" vector particles to the heavy hadron effective chiral Lagrangian. This has strong motivations both from the phenomenological and aesthetic standpoints. An application to the already observed D \rightarrow \overbar{K^*} weak transition amplitude is discussed.Comment: 19 pages, LaTeX documen

Note on Tests of the Factorization Hypothesis and the Determination of Meson Decay Constants

We discuss various tests of the factorization hypothesis making use of the close relationship between semi-leptonic and factorized nonleptonic decay amplitudes. It is pointed out that factorization leads to truely model-independent predictions for the ratio of nonleptonic to semi-leptonic decay rates, if in the nonleptonic decay a spin one meson of arbitrary mass or a pion take the place of the lepton pair. Where the decay constants of those mesons are known, these predictions represent ideal tests of the factorization hypothesis. In other cases they may be used to extract the decay constants. Currently available data on the decays $\bar B^0 \to D^+\pi^-,\, D^{*+}\pi^-,\, D^+\varrho^-,\, D^{*+}\varrho^-$ are shown to be in excellent agreement with the factorization results. A weighted average of the four independent values for the QCD coefficient $a_1$ extracted from the data gives $a_1=1.15\pm 0.06$ suggesting that it may be equal to the Wilson coefficient $c_1(\mu)$ evaluated at the scale $\mu = m_b$.Comment: (9 pages, ReVTeX, no figures), HD-THEP-92-3

FAST, a method based on split-GFP for the detection in solution of proteins synthesized in cell-free expression systems

Cell-free protein synthesis (CFPS) systems offer a versatile platform for a wide range of applications. However, the traditional methods for detecting proteins synthesized in CFPS, such as radioactive labeling, fluorescent tagging, or electrophoretic separation, may be impractical, due to environmental hazards, high costs, technical complexity, and time consuming procedures. These limitations underscore the need for new approaches that streamline the detection process, facilitating broader application of CFPS. By harnessing the reassembly capabilities of two GFP fragments—specifically, the GFP1-10 and GFP11 fragments—we have crafted a method that simplifies the detection of in vitro synthesized proteins called FAST (Fluorescent Assembly of Split-GFP for Translation Tests). FAST relies on the fusion of the small tag GFP11 to virtually any gene to be expressed in CFPS. The in vitro synthesized protein:GFP11 can be rapidly detected in solution upon interaction with an enhanced GFP1-10 fused to the Maltose Binding Protein (MBP:GFP1-10). This interaction produces a fluorescent signal detectable with standard fluorescence readers, thereby indicating successful protein synthesis. Furthermore, if required, detection can be coupled with the purification of the fluorescent complex using standardized MBP affinity chromatography. The method's versatility was demonstrated by fusing GFP11 to four distinct E. coli genes and analyzing the resulting protein synthesis in both a homemade and a commercial E. coli CFPS system. Our experiments confirmed that the FAST method offers a direct correlation between the fluorescent signal and the amount of synthesized protein:GFP11 fusion, achieving a sensitivity threshold of 8 ± 2 pmol of polypeptide, with fluorescence plateauing after 4 h. Additionally, FAST enables the investigation of translation inhibition by antibiotics in a dose-dependent manner. In conclusion, FAST is a new method that permits the rapid, efficient, and non-hazardous detection of protein synthesized within CFPS systems and, at the same time, the purification of the target protein

An assessment framework for REDD+ benefit sharing mechanisms within a forest policy mix

Policy instruments for implementing the Reducing Emissions from Deforestation and Forest Degradation and the enhancement of forest carbon stocks (REDD+) mechanism operate within an orchestra of national contexts and policy mixes that affect the forest and other land sectors. How will policymakers choose between the myriad of options for distributing REDD+ benefits, and be able to evaluate its potential effectiveness, efficiency and equity (3Es) within the various institutional and governance structures a where such a REDD+ benefit sharing mechanism is situated? This is a pressing issue given the results- based aspect of REDD+. We present here a three-element assessment framework for evaluating outcomes and performance of REDD+ benefit sharing mechanisms, using the criteria of effectiveness, efficiency and equity: (1) the structures (objective and policies) of a REDD+ benefit sharing mechanism; (2) the broader institutional and policy contexts underlying forest governance; and (3) outcomes of REDD+ including emissions reductions, ecosystem service provision and poverty alleviation. A strength of the assessment framework is its flexible design to incorporate indicators relevant to different contexts; this helps to generate a shared working understanding of what is to be evaluated in the different REDD+ benefit sharing mechanisms (BSMs) across complex socio- political contexts. In applying the framework to case studies, the assessment highlights trade-offs among the 3Es, and the need to better manage access to information, monitoring and evaluation, consideration of local perceptions of equity and inclusive decision-making processes. The framework aims not to simplify complexity but rather, serves to identify actionable ways forward towards a more efficient, effective and equitable implementation and re- evaluation of REDD+ BSMs as part of reflexive policymaking

Structural analysis of ultrafast extended x-ray absorption fine structure with subpicometer spatial resolution: Application to spin crossover complexes

We present a novel analysis of time-resolved extended x-ray absorption fine structure (EXAFS) spectra based on the fitting of the experimental transients obtained from optical pump/x-ray probe experiments. We apply it to the analysis of picosecond EXAFS data on aqueous [FeII (bpy)3] 2+, which undergoes a light induced conversion from its low-spin (LS) ground state to the short-lived (τ≈650 ps) excited high-spin (HS) state. A series of EXAFS spectra were simulated for a collection of possible HS structures from which the ground state fit spectrum was subtracted to generate transient difference absorption (TA) spectra. These are then compared with the experimental TA spectrum using a least-squares statistical analysis to derive the structural change. This approach reduces the number of required parameters by cancellation in the differences. It also delivers a unique solution for both the fractional population and the extracted excited state structure. We thus obtain a value of the Fe-N bond elongation in the HS state with subpicometer precision (0.203±0.008 Å). © 2009 American Institute of Physics.This work was funded by the Swiss National Science Foundation via Contract Nos. 620–066145, 200021–107956, PP002–110464, 200020–116023, 200021–105239, and 200020-116533.Peer Reviewe