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151.
William C. Neuhaus Ian J. Bakanas Joseph R. Lizza Charles T. Boon Jr. 《Green Chemistry Letters and Reviews》2016,9(1):39-43
Novel eco-friendly tetramethylguanidinium propanesulfonic acid trifluoromethylacetate ([TMGHPS][TFA]) ionic liquid was developed as catalyst and medium for the Fischer indole synthesis of a wide variety of hydrazines and ketones. The indole products were isolated in high yields and with minimal amounts of organic solvent. This reaction showed that [TMGHPS][TFA] can be regenerated and reused with reproducible yields without eroding the integrity of the ionic liquid. 相似文献
152.
153.
154.
Hejian Xiong Xiuying Li Peiyuan Kang John Perish Frederik Neuhaus Jonathan E. Ploski Sven Kroener Maria O. Ogunyankin Jeong Eun Shin Joseph A. Zasadzinski Hui Wang Paul A. Slesinger Andreas Zumbuehl Zhenpeng Qin 《Angewandte Chemie (International ed. in English)》2020,59(22):8608-8615
Remote and minimally‐invasive modulation of biological systems with light has transformed modern biology and neuroscience. However, light absorption and scattering significantly prevents penetration to deep brain regions. Herein, we describe the use of gold‐coated mechanoresponsive nanovesicles, which consist of liposomes made from the artificial phospholipid Rad‐PC‐Rad as a tool for the delivery of bioactive molecules into brain tissue. Near‐infrared picosecond laser pulses activated the gold‐coating on the surface of nanovesicles, creating nanomechanical stress and leading to near‐complete vesicle cargo release in sub‐seconds. Compared to natural phospholipid liposomes, the photo‐release was possible at 40 times lower laser energy. This high photosensitivity enables photorelease of molecules down to a depth of 4 mm in mouse brain. This promising tool provides a versatile platform to optically release functional molecules to modulate brain circuits. 相似文献
155.
156.
The paper presents some permutation test procedures for multivariate location. The tests are based on projected univariate versions of multivariate data. For one-sample cases, the tests are affine invariant and strictly distribution-free for the symmetric null distribution with elliptical direction and their permutation counterparts are conditionally distribution-free when the underlying null distribution of the sample is angularly symmetric. For multi-sample cases, the tests are also affine invariant and permutation counterparts of the tests are conditionally distribution-free for any null distribution with certain continuity. Hence all of the tests in this paper are exactly valid. Furthermore, the equivalence, in the large sample sense, between the tests and their permutation counterparts are established. The power behavior of the tests and of their permutation counterparts under local alternative are investigated. A simulation study shows the tests to perform well compared with some existing tests in the literature, particularly when the underlying null distribution is symmetric whether light-tailed or heavy-tailed. For revealing the influence of data sparseness on the effect of the test, some simulations with different dimensions are also performed. 相似文献
157.
The d + d, t + p and h + n relative wavefunctions and their asymptotic normalizations are considered in the framework of the generator coordinate method
(GCM) and compared with ATMS (amalgamation of two-body correlation into multiple scattering processes) method which used the
realistic Reid soft core interaction. The asymptotic normalization of relative wavefunctions provide various coupling constants,
the cluster probability amplitude (the so-called Z
1/2-factor) and matter RMS radii. These wavefunctions are also used to obtain 4He − d − d, 4He − t − p and 4He − h − n vertex functions in the virtual decay of 4He. The extrapolation of vertex functions for negative values of q
2 upto the corresponding poles provide the vertex constants which are comparable with other estimates. It is noticed that in
GCM the coupling constants C
2 for 4He − d − d vertex is less than 2 as has been obtained in the forward dispersion relation technique. 相似文献
158.
Georg Neuhaus 《Journal of multivariate analysis》1976,6(1):95-110
The asymptotic power of the Cramér-von Mises test (CvM test) when parameters are estimated from the data is studied under certain local (contiguous) alternatives. The notion of (asymptotic) direction and distance from the null hypothesis of alternatives is introduced, and it is shown that there exist directions with maximum, minimum, and arbitrary intermediate power. For each direction, there exists a natural asymptotic testing problem with an uniformly most powerful test that is compared with the CvM test. For that, the notion of asymptotic local efficiency (ALE) of the CvM test is introduced. finally, the influence of more information on the (unknown) parameter is studied for three tests of the CvM-type for independence. it is shown that for certain directions, a better knowledge of the parameter may increase the power, and for other ones decrease it. These properties are analogous to that of the X2-test in similar situations. 相似文献
159.
160.
Hammack W Carson MC Neuhaus BK Hurlbut JA Nochetto C Stuart JS Brown A Kilpatrick D Youngs K Ferbos K Heller DN 《Journal of AOAC International》2003,86(6):1135-1143
An existing method for chloramphenicol (CAP) determination in shrimp using a gas chromatograph with electron capture detector was adapted for confirmation of CAP with a liquid chromatograph interfaced to a triple quadrupole mass spectrometer. CAP residues are extracted from tissue with ethyl acetate, isolated via liquid-liquid extraction, and concentrated by evaporation. Extracts are chromatographed by using a reversed-phased column and analyzed by electrospray negative mode tandem mass spectrometry. Four product ions (m/z 152, 176, 194, and 257) of precursor m/z 321 were monitored. Moving from gas chromatography to liquid chromatography-tandem mass spectrometry improved the sensitivity of the method greatly, enabling reliable confirmation of CAP residues at 0.3 microg/kg (ppb). The method meets confirmation criteria recommended by the U.S. Food and Drug Administration and 4-point identification criteria established by the European Union. With slight modifications to accommodate different equipment, the method was validated in 3 laboratories. 相似文献