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The objective of this study was to provide an updated meta-analysis of the efficacy and safety of huperzine A (HupA) in Alzheimer's disease (AD). We searched for randomized trials comparing HupA with placebo in the treatment of AD. The primary outcome measures were mini-mental state examination (MMSE) and activities of daily living scale (ADL). Data were extracted from four randomized clinical trials and analyzed using standard meta-analysis and meta-regression methods. Oral administration of HupA for 8-24 weeks (300-500 microg daily) led to significant improvements in MMSE and ADL. The results of meta-regression showed that the estimated effect size of MMSE and ADL was increased over the treatment time. Most adverse events were cholinergic in nature and no serious adverse events occurred. Huperzine A is a well-tolerated drug that could significantly improve cognitive performance and ADL in patients with AD.

Consider a two-party correlation that can be generated by performing local measurements on a bipartite quantum system. A question of fundamental importance is to understand how many resources, which we quantify by the dimension of the underlying quantum system, are needed to reproduce this correlation. In this Letter, we identify an easy-to-compute lower bound on the smallest Hilbert space dimension needed to generate a given two-party quantum correlation. We show that our bound is tight on many well-known correlations and discuss how it can rule out correlations of having a finite-dimensional quantum representation. We show that our bound is multiplicative under product correlations and also that it can witness the non-convexity of certain restricted-dimensional quantum correlations.In what ranks as one of the most important achievements of modern physics, it was shown by John Bell in 1964 that some correlations generated within the framework of quantum mechanics can be nonlocal, in the sense that the statistics generated by quantum mechanics cannot always be reproduced by a local hidden-variable model [1,2]. Over the last 40 years, there have been significant efforts in trying to verify this fact experimentally. The first such experimental data [3] was published in 1972 and this remains an active area of research [4]. Moreover, as a central concept in quantum physics and quantum information theory, fully understanding quantum entanglement and nonlocality still remains a very interesting and important problem with far-reaching applications. Indeed, profound relationships between quantum nonlocality and other fundamental quantum concepts or phenomena such as entanglement measures [5,6], entanglement distillation [7,8], and teleportation [9] have been identified. Meanwhile, for many tasks, e.g. in cryptography [10,11], it has been realized that due to quantum nonlocality, quantum strategies enjoy remarkable advantages over their classical counterparts.However, even though quantum nonlocal effects can lead to interesting and often surprising advantages in some applications, this does not paint the full picture. After all, for practical applications, it is just as important to understand the amount of quantum resources required for these advantages to manifest. For instance, if there is an exponential blowup in the amount of resources required, then whatever advantage gained by employing quantum mechanics may not be useful in practice. Quantifying the amount of quantum resources needed to perform a certain task is the central focus of this Letter.We study quantum nonlocality from the viewpoint of two-party quantum correlations that arise from a Bell experiment. A two-party Bell experiment is performed between two parties, Alice and Bob, whose labs are set up in separate locations. Alice (resp. Bob) has in her possession a measurement apparatus whose possible settings are labelled by the elements of a finite set X (resp. Y ) and the possible measurement outcomes are labelled by a finite set A (resp. B). After repeat...