Chemoenzymatic peptide synthesis is potentially the most cost‐efficient technology for the synthesis of short and medium‐sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required and racemisation does not occur rendering purification easier compared to chemical peptide synthesis. In this paper, a novel interconversion reaction of peptide C‐terminal α‐carboxamides into primary alkyl esters with alcalase was used to develop a fully enzymatic peptide synthesis strategy. For each elongation step a cost‐efficient amino acid carboxamide building block was used followed by the interconversion of the elongated peptide carboxamide to the corresponding primary alkyl ester. These peptide esters are the starting materials for the next enzymatic peptide elongation step. 相似文献
SU-8 is often used as a structural material in Microsystems. In this work, the outgassing characteristics from such cross-linked SU-8 layers are studied using mass spectrometry and gas-chromatography techniques. With these methods the composition of the released matter can be identified, also the outgassing rate can be quantitatively characterized. A qualitative estimate of outgassing from SU-8 is given for cross-linked layers. The effect of hard-bakes is studied in situ by measuring at typical hard-bake temperatures. These tests indicate that a hard-bake is needed to provide good performance in UHV environments. Using gas-chromatography the outgassing rate from SU-8 is determined. The total outgassing rate is inversely proportional with time which further illustrates the effect of a hard-bake step. 相似文献
H 3 R inverse agonists based on an aminopropoxy‐phenyloxazoline framework constitute highly valuable druglike lead compounds that display efficacy in a mouse model of recognition memory.
This paper aims to identify and evaluate a potential ecological network including core areas and large-scale corridors in the İzmir Province and its surrounding areas, Turkey. It is one of the first studies on the connectivity for mammal species and the detection of potential ecological corridors for Turkey. Four wide-ranging species (Hyaena hyaena, Lynx lynx, Caracal caracal, and Felis chaus) have been chosen as target species. Existing Key Biodiversity Areas (KBAs) and surrounding lands have been evaluated based on a three criteria: (1) vegetation/habitat types, (2) carrying capacity and (3) road density using simple GIS-based models.The results are evaluated using the Minimum Viable Metapopulation (MVMP) standards. No KBA in the study region has a Key Population (KP) or Minimum Viable Population (MVP) with the exception of Boz Dağlar. Least cost-path analysis has been applied to identify linkages between KBAs relevant for the four target species. The conclusion is that it is possible to maintain MVPs in the region when the KBAs are linked by ecological corridors. 相似文献
A subset of ADA is introduced, ADA-CF, to study the basic synchronization and communication primitive of ADA, the rendezvous. Basing ourselves on the techniques introduced by Apt, Francez and de Roever for their CSP proof system, we develop a Hoare-style proof system for proving partial correctness properties which is sound and relatively complete. The proof system is then extended to deal with safety, deadlock, termination and failure. No prior exposure of the reader to parallel program proving techniques is presupposed. Two non-trivial example proofs are given of ADA-CF programs; the first one concerns a buffered producer-consumer algorithm, the second one a parallel sorting algorithm due to Brinch Hansen. Features of ADA expressing dynamic process creation and realtime constraints are not covered by our proof methods. Consequently, we do not claim that the methods described can be extended to full ADA without serious additional further research. 相似文献
The objective of this study was to develop and parametrize a mathematical model of the sensitivity of pooled sampling of faeces to detect Salmonella infection in pigs. A mathematical model was developed to represent the effect of pooling on the probability of Salmonella isolation. Parameters for the model were estimated using data obtained by collecting 50 faecal samples from each of two pig farms. Each sample was tested for Salmonella at individual sample weights of 0.1, 0.5, 1, 10 and 25 g and pools of 5, 10 and 20 samples were created from the individual samples. The highest test sensitivity for individual samples was found at 10 g (90% sensitivity), with the 25 g test sensitivity equal to 83%. For samples of less than 10 g, sensitivity was found to reduce with sample weight. Incubation for 48 h was found to produce a more sensitive test than incubation for 24 h. Model results found increasing sensitivity with more samples in the pool, with the pools of 5, 10 and 20 being more sensitive than individual sampling, and the pools of 20 being the most sensitive of those considered. 相似文献
We offer a new formal criterion for agent-centric learning in multi-agent systems, that is, learning that maximizes one’s rewards in the presence of other agents who might also be learning (using the same or other learning algorithms). This new criterion takes in as a parameter the class of opponents. We then provide a modular approach for achieving effective agent-centric learning; the approach consists of a number of basic algorithmic building blocks, which can be instantiated and composed differently depending on the environment setting (for example, 2- versus n-player games) as well as the target class of opponents. We then provide several specific instances of the approach: an algorithm for stationary opponents, and two algorithms for adaptive opponents with bounded memory, one algorithm for the n-player case and another optimized for the 2-player case. We prove our algorithms correct with respect to the formal criterion, and furthermore show the algorithms to be experimentally effective via comprehensive computer testing. 相似文献
The research evaluated the efficacy of an intervention to reduce the onset and extent of binge drinking during the 1st year of college. The approach was on influencing the students before they start college, through their parents, during the critical time between high school graduation and the beginning of college. Specifically, parents were educated about binge drinking and how to convey information to their teens, and then encouraged to talk with their teens just before their teens embarked on their college education. Teens whose parents implemented the intervention materials were compared with a control sample during their 1st semester on drinking outcomes, perceptions about drinking activities, perceived parental and peer approval of drinking, and drinking-related consequences. As anticipated, teens in the treatment condition were significantly different (p?,?.05)on nearly all outcomes in the predicted directions (e.g., lower drinking tendencies, drinking consequences). The benefits of a parent-based intervention to prevent college drinking are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献