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371.
This report describes a methodology for obtaining optimal operating rules for the equipment influencing the climatic conditions inside a greenhouse. The optimization is based on an economic criterion which takes into account the expected income from the crops versus the cost of operating and maintaining the greenhouse.The optimal control function is characterized and the analytic conditions for optimality are derived. A numerical scheme for obtaining the desired control is described and a sensitivity analysis is then carried out. This analysis enables derivation of simple operating rules for a real greenhouse. 相似文献
372.
Shmuel Glasner 《Israel Journal of Mathematics》1975,22(1):87-92
We show that a minimal metric flowX whose enveloping semigroupE(X), contains finitely many minimal ideals, is a PI-flow; i.e.X has a proximal extensionX' which can be built by iterating proximal and isometric extensions (starting with the trivial one point flow). An example is given which shows that the converse theorem does not hold. Finally, we show that ifX is a minimal, non-trivial, metric, weakly mixing flow and the group action is nilpotent thenE(X) contains infinitely many minimal ideals. 相似文献
373.
A countable family of minimal transformations (X, Z) is described for which no pair have a non-trivial common factor, and so that no pair is disjoint. This answers in the negative
a question of H. Furstenberg. 相似文献
374.
Ainelly Veerendhar Shmuel Cohen Julia Frant Claudiu T. Supuran Reuven Reich Eli Breuer 《Heteroatom Chemistry》2015,26(4):257-269
Carbamoylphosphonates (CPOs) have recently been identified as extracellular in vivo active inhibitors of the cancer and metastasis‐promoting extracellular enzymes, carbonic anhydrases (CAs) IX and XII, and matrix metalloproteinase‐2 (MMP‐2). This article describes the stereoselective synthesis and the evaluation of the biological properties of a pair of enantiomeric aminoalkylcarbamoylphosphonates, which have been enantioselectively synthesized from l ‐serine, using functional group‐transformations. The structures of the enantiomeric products have been determined by X‐ray crystallography. The enantiomeric purities of compounds have been confirmed by chiral shift reagent NMR experiments and by circular dichroism. In vitro evaluation of the CPOs synthesized revealed that they possess micromolar IC50 inhibitory action against CAIX and CAXII. The two enantiomers as well as the racemic or optically inactive ones do not differ by any significant extent from previously reported CPOs’ CA inhibitory values. On the other hand, MMPs inhibitory activities are rather weak; only MMP‐2 showed a notable IC50 value. 相似文献
375.
The energy and approximate structure of certain S(0)/S(1) conical intersections (CI) are shown computationally to be deducible from those of two bound states: the first triplet (T(1)), which is iso-energetic with the CI, and the second excited singlet state (S(2)). This is demonstrated for acepentalene (I) and its perfluoro derivative (II) using the twin state concept for three states systems and based on the fact that the triplet T(1) is almost degenerate with the CI. The stable S(2) (C(3v) configuration) state exhibits unusual exaltation of Jahn-Teller active degenerate mode-ν(JT) = 2058 cm(-1) (~500 cm(-1) higher than analogous e-mode of the symmetric (C(3v)) T(1) and the dianion I(-2) or any C-C vibration of the Jahn-Teller distorted (C(s)) ground state minimum). The acepentalene molecule, whose rigid structure and possibility to attain the relatively high symmetry C(3v) configuration, is a particularly suitable candidate for this purpose. 相似文献
376.
Eran Zahavy Vered Heleg-Shabtai Yossi Zafrani Daniele Marciano Shmuel Yitzhaki 《Journal of fluorescence》2010,20(1):389-399
Fluorescent semiconductor nanocrystals (q-dots) benefit from practical features such as high fluorescence intensity, broad
excitation band and emission diameter dependency. These unique spectroscopic characterizations make q-dots excellent candidates
for new fluorescent labels in multi-chromatic analysis, such as Flow-Cytometry (FCM). In this work we shall present new possibilities
of multi-labeling and multiplex analysis of pathogenic bacteria, by Flow-Cytometry (FCM) analysis and new specific IgG—q-dots
conjugates. We have prepared specific conjugates against B. anthracis spores (q-dots585-IgGαB. anthracis and q-dots655-IgGαB.anthracis). These conjugates enabled us to achieve double staining of B. anthracis spores which improve the FCM analysis specificity versus control Bacillus spores. Moreover, multiplexed analysis of B. anthracis spores and Y. pestis bacteria was achieved by using specific antibodies labeled with different q-dots to obtain: q-dots585-IgGαB. anthracis and q-dots655-IgGαY.pestis, each characterized by its own emission peak as a marker. Specific and sensitive multiplex analysis for both pathogens has
been achieved, down to 103 bacteria per ml in the sample. 相似文献
377.
Knop Dušan Koutecký Martin Levin Asaf Mnich Matthias Onn Shmuel 《Mathematical Programming》2023,200(1):199-227
Mathematical Programming - N-fold integer programs (IPs) form an important class of block-structured IPs for which increasingly fast algorithms have recently been developed and successfully... 相似文献