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61.
Colin T. Whittemore Annie R. Henderson 《Journal of the science of food and agriculture》1977,28(6):506-510
Silage made from young grass and which contained an average of 34.6 g nitrogen (N), 19.5 MJ gross energy (GE) and 271 g fibre/kg dry matter (DM), was found to have digestibility coefficients to sows of 0.73 for N, 0.60 for GE, 0.60 for cellulose and 0.51 for fibre. The addition of a cellulase enzyme preparation to the grass prior to ensilage decreased the fibre content by 38 g/kg DM and increased the water soluble carbohydrate (WSC) content by 154 g/kg DM, but did not influence the digestibility of the silage. 相似文献
62.
Annie Bonavita-Cougourdan Jean-Luc Clement Catherine Lange 《Journal of chemical ecology》1993,19(7):1461-1477
In the antCamponotus vagus, when selected foragers that had been earlier removed from the foraging arena and brood-tenders that had been earlier removed from the nest were placed together in a foraging arena, most of the brood-tenders and only a few of the selected foragers were carried back to the nest by nonselected foragers. We hypothesize that cuticular hydrocarbons serve as a cue that allows foragers to discriminate between members of their own subcaste and brood-tenders. It has been established that the proportions of certain hydrocarbons, which are the same regardless of the colony studied, vary from one worker subcaste to another and thus constitute a specific chemical signature. These hydrocarbons belong to a wide range of chemical families (alkanes, monomethylalkanes, and dimethylalkanes). The greatest differences between the two subcastes were observed on the thorax of workers. Principal component analyses performed on the hydrocarbons (or hydrocarbon combinations) corresponding to the 45 main peaks in the cuticular profiles of the head and thorax of brood-tenders and foragers of several colonies show that there exist quantitative differences between the various signatures that characterize the colony, the worker subcastes, and the various body parts within the same species, which can be classified in a hierarchy where the differences between worker subcastes are less pronounced than those between body parts or between colonies. 相似文献
63.
Mortier KA Renard V Verstraete AG Van Gussem A Van Belle S Lambert WE 《Analytical chemistry》2005,77(14):4677-4683
A quantitative method for the simultaneous determination of docetaxel (Taxotere), paclitaxel (Taxol), 6alpha-hydroxypaclitaxel, and p-3'-hydroxypaclitaxel in human plasma and oral fluid is developed and validated. Oral fluid (this term is now preferred to saliva) was sampled with a Salivette collection device. The procedure used a simple liquid/liquid extraction with methyl tert-butyl ether followed by LC-ESI-MS/MS. Gradient elution was applied and provided increased robustness to ion suppression by the drug formulation vehicle (polysorbate 80 and Cremophor EL). Adduct ion formation with sodium and potassium was noticed and controlled by mobile-phase optimization. The protonated analytes generated in the positive ion mode were monitored through multiple reaction monitoring. Calibration was performed by internal standardization with cephalomannine, and regression curves were constructed ranging between 2 and 1000 ng/mL in plasma and 0.125 and 62.5 ng/mL in oral fluid, using a weighing factor of 1/x2. The regression curves were quadratic for paclitaxel and docetaxel and linear for the paclitaxel metabolites. Accuracy varied from 91.3 to 103.6%, and imprecision did not exceed 12.7% for all analytes in plasma and oral fluid. In conclusion, a sensitive and robust method was obtained, which fulfilled all validation criteria. 相似文献
64.
Annie Blandin 《电信纪事》2006,61(7-8):759-772
The sector-based model stemming from the regulatory framework for telecommunications, was extended to electronic communications, a term which takes into account the convergence of the telecommunications, broadcasting andIt sectors. At the same time, this model tends to dissolve in the general competition rules which are supposed to replace the sectoral regulation. Already, this regulation applies exclusively to operators having a significant market power on the relevant markets. But this competition model itself is subordinated to general interest objectives, as universal service or cultural diversity. Thus, a new evolution is initiated, where the objectives of contents regulation could help to redefine some aspects of network regulation. 相似文献
65.
The emerging number of life‐threatening invasive fungal infections caused by drug‐resistant Candida strains urges the need for the development and application of fundamentally new and safe antifungal strategies in the clinical treatment. Recent studies demonstrated that the extracellular cysteine‐rich and cationic antifungal proteins (crAFPs) originating from filamentous fungi, and de novo designed synthetic peptide derivatives of these crAFPs provide a feasible basis for this approach. This mini‐review focuses on the global challenges of the anti‐Canidia therapy and on the crAFPs as potential drug candidates to overcome existing problems. The advantages and limitations in the use of crAFPs and peptide derivatives compared to those of conventional antifungal drugs will also be critically discussed. 相似文献
66.
Ming Tian Taylor Ticer Qikun Wang Sierra Walker Anthony Pham Annie Suh Sara Busatto Irina Davidovich Rawan Al‐Kharboosh Laura Lewis‐Tuffin Baoan Ji Alfredo Quinones‐Hinojosa Yeshayahu Talmon Shane Shapiro Felix Rückert Joy Wolfram 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)
Extracellular vesicles secreted from adipose‐derived mesenchymal stem cells (ADSCs) have therapeutic effects in inflammatory diseases. However, production of extracellular vesicles (EVs) from ADSCs is costly, inefficient, and time consuming. The anti‐inflammatory properties of adipose tissue‐derived EVs and other biogenic nanoparticles have not been explored. In this study, biogenic nanoparticles are obtained directly from lipoaspirate, an easily accessible and abundant source of biological material. Compared to ADSC‐EVs, lipoaspirate nanoparticles (Lipo‐NPs) take less time to process (hours compared to months) and cost less to produce (clinical‐grade cell culture facilities are not required). The physicochemical characteristics and anti‐inflammatory properties of Lipo‐NPs are evaluated and compared to those of patient‐matched ADSC‐EVs. Moreover, guanabenz loading in Lipo‐NPs is evaluated for enhanced anti‐inflammatory effects. Apolipoprotein E and glycerolipids are enriched in Lipo‐NPs compared to ADSC‐EVs. Additionally, the uptake of Lipo‐NPs in hepatocytes and macrophages is higher. Lipo‐NPs and ADSC‐EVs have comparable protective and anti‐inflammatory effects. Specifically, Lipo‐NPs reduce toll‐like receptor 4‐induced secretion of inflammatory cytokines in macrophages. Guanabenz‐loaded Lipo‐NPs further suppress inflammatory pathways, suggesting that this combination therapy can have promising applications for inflammatory diseases. 相似文献
67.
Elisabetta DE MARIA Abdorrahim BAHRAMI Thibaud L’YVONNET Amy FELTY Daniel GAFFÉ Annie RESSOUCHE Franck GRAMMONT 《Frontiers of Computer Science》2022,16(3):163404-115
Having a formal model of neural networks can greatly help in understanding and verifying their properties, behavior, and response to external factors such as disease and medicine. In this paper, we adopt a formal model to represent neurons, some neuronal graphs, and their composition. Some specific neuronal graphs are known for having biologically relevant structures and behaviors and we call them archetypes. These archetypes are supposed to be the basis of typical instances of neuronal information processing. In this paper we study six fundamental archetypes (simple series, series with multiple outputs, parallel composition, negative loop, inhibition of a behavior, and contralateral inhibition), and we consider two ways to couple two archetypes: (i) connecting the output(s) of the first archetype to the input(s) of the second archetype and (ii) nesting the first archetype within the second one. We report and compare two key approaches to the formal modeling and verification of the proposed neuronal archetypes and some selected couplings. The first approach exploits the synchronous programming language Lustre to encode archetypes and their couplings, and to express properties concerning their dynamic behavior. These properties are verified thanks to the use of model checkers. The second approach relies on a theorem prover, the Coq Proof Assistant, to prove dynamic properties of neurons and archetypes. 相似文献
68.
Stability effects associated with the introduction of a partial and a complete Ca2+-binding site into human lysozyme 总被引:2,自引:0,他引:2
Haezebrouck Petra; Baetselier Annie De; Joniau Marcel; Dael Herman Van; Rosenberg Steve; Hanssens Ignace 《Protein engineering, design & selection : PEDS》1993,6(6):643-649
Two mutants of human lysozyme were synthesized. Mutant A92D,in which Ala92 was substituted by Asp, contains a partial Ca2+-bindingsite and mutant M4, in which Ala83, Gm86, Asn88 and Ala92 werereplaced by Lys, Asp, Asp and Asp respectively, contains thecomplete Ca -binding site of bovine a-lactalbumin. The Ca2+-bindingconstants of wild type human lysozyme and of mutants A92D andM4, measured at 25C and pH 7.5, were 2(1) x 102 M"1, 8(2)x l^M"1 and 9(0.5) x 10* M"1 respectively. Information gatheredfrom mkrocalorimetrk and CD spectro-scopic measurements indicatesthat the conformational changes of the M4 mutant lysozyme, inducedby Ca2+ binding, are smaller than those observed for bovinea-lactalbumin and for the Ca2+-binding equine lysozyme. At pH4.5, the thermostability of both the apo and Ca2+ forms of theA92D human was decreased in comparison with that of native humanlysozyme. In particular, within the apo form of this mutantan a-helix-containing sequence was destabilized. In contrast,at the same pH the thermostability of the apo and Ca2+ formsof the M4 mutant lysozyme was increased. The e-ammonium groupof the Lys83 side chain is assumed to be responsible for thestabilization of the apo form of this mutant. 相似文献
69.
Any node in a wireless sensor network is a resource constrained device in terms of memory, bandwidth, and energy, which leads to a large number of packet drops, low throughput, and significant waste of energy due to retransmission. This paper presents a new approach for predicting congestion using a probabilistic method and controlling congestion using new rate control methods. The probabilistic approach used for prediction of the occurrence of congestion in a node is developed using data traffic and buffer occupancy. The rate control method uses a back-off selection scheme and also rate allocation schemes, namely rate regulation (RRG) and split protocol (SP), to improve throughput and reduce packet drop. A back-off interval selection scheme is introduced in combination with rate reduction (RR) and RRG. The back-off interval selection scheme considers channel state and collision-flee transmission to prevent congestion. Simulations were conducted and the results were compared with those of decentralized predictive congestion control (DPCC) and adaptive duty-cycle based congestion control (ADCC). The results showed that the proposed method reduces congestion and improves performance. 相似文献
70.
Andrew J. Chappell Daniel M. Allwood Rebecca Johns Samantha Brown Kiran Sultana Annie Anand Trevor Simper 《Journal of the International Society of Sports Nutrition》2018,15(1):42