A method to measure orbital angular momentum (OAM) states of light beams by using gradually-changing-period gratings is reported. Two kinds of gradually-changing-period gratings were used for the measurement of OAM states. The OAM states of the incident beam can be measured easily from the Hermite-Gaussian-like diffraction patterns. The simulation results agree well with the experiments.

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Thirteen compounds were isolated from the anomalous fruits of Gleditsia sinensis on the basis of bioassay-guided fractionation. These saponins together with six analogues or related compounds were tested for their cytotoxicities against six tumor cell lines by the MTT method. The induction of apoptosis in HL-60 cells by these compounds was determined through flow cytometric analysis. Some structure-activity relationships in cytotoxicity and induction of apoptosis were identified. The evaluation of the cytotoxicity and the ability to induce apoptosis revealed that some important structural features are required for activity. A valuable model which enables prediction of their activities was established and may be employed for the drug design of new Gleditsia saponin analogues.

A quite popular approach to solving the Causal Exclusion Problem is to adopt a counterfactual theory of causation. In this paper, I distinguish three versions of the Causal Exclusion Argument. I argue that the counterfactualist approach can block the first two exclusion arguments, because the Causal Inheritance Principle and the Upward Causation Principle upon which the two arguments are based respectively are problematic from the perspective of the counterfactual account of causation. However, I attempt to show that the counterfactualist approach is unable to refute a sophisticated version (i.e. the third version) of the exclusion argument in that the Downward Causation Principle, a premise of the third exclusion argument, is actually implied by the counterfactual theory of causation. Therefore, even if other theories of causation might help the non-reductive physicalist to solve the exclusion problem, the counterfactual theory of causation cannot.