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1.
Bao WANG Penghang YIN Andrea Louise BERTOZZI P. Jeffrey BRANTINGHAM Stanley Joel OSHER Jack XIN 《数学年刊B辑(英文版)》2019,40(6):949-966
Real-time crime forecasting is important. However, accurate
prediction of when and where the next crime will happen is
difficult. No known physical model provides a reasonable
approximation to such a complex system. Historical crime data are
sparse in both space and time and the signal of interests is weak.
In this work, the authors first present a proper representation of
crime data. The authors then adapt the spatial temporal residual
network on the well represented data to predict the distribution of
crime in Los Angeles at the scale of hours in neighborhood-sized
parcels. These experiments as well as comparisons with several
existing approaches to prediction demonstrate the superiority of the
proposed model in terms of accuracy. Finally, the authors present a
ternarization technique to address the resource consumption issue
for its deployment in real world. This work is an extension of our
short conference proceeding paper [Wang, B., Zhang, D., Zhang, D.
H., et al., Deep learning for real time Crime forecasting, 2017,
arXiv: 1707.03340]. 相似文献
2.
A space is left-separated if it has a well ordering for which initial segments are closed. We explore when the union of two left-separated spaces must be left-separated. We prove that if X and Y are left-separated and \({X \cup Y}\) is locally countable, then whenever \({{\rm ord}_\ell(Y ) \leq \omega_{1}, X \cup Y}\) is left-separated. In 1986, Fleissner [2] proved that if a space has a point-countable base, then it is left-separated if and only if it is \({\sigma}\)-weakly separated. We provide a new proof of this result using elementary submodels and add an additional characterization. 相似文献
3.
A new organic reference material,l‐glutamic acid,USGS41a,for δ13C and δ15N measurements − a replacement for USGS41 下载免费PDF全文
4.
In this paper we address the existence of smooth manifolds proper homotopy equivalent to nonuniform arithmetic manifolds M = Γ\G/K that are not homeomorphic to it. While the manifolds M are properly rigid if rankℚ(Γ) ≤ 2, we show that the so‐called virtual structure group has infinite rank as a ℚ‐vector space if rankℚ(Γ) ≥ 4.© 2015 Wiley Periodicals, Inc. 相似文献
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6.
Stanley E. Ukwueze Patience O. Osadebe Festus B.C. Okoye 《Natural product research》2015,29(18):1728-1734
Bioactivity-guided fractionation of methanol extract from the leaves of Psidium guajava L. (Myrtaceae) yielded a new benzophenone glycoside, Guajaphenone A (2) together with two known compounds, Garcimangosone D (1) and Guaijaverin (3). Their structures were elucidated by analysis of spectroscopic data including 1D and 2D NMR and electrospray ionisation mass spectrometry (ESI-MS). The isolated compounds were screened against standard strains of Gram-positive and Gram-negative bacteria using broth dilution assay method, and the MIC values determined and compared with reference antibiotic ceftriaxone. They were found to have significant antibacterial activities against Escherichia coli and Staphylococcus aureus with all of them showing better activities against S. aureus, but displaying weaker activities, in comparison to ceftriaxone. However, despite reduced effect of these compounds against the organisms, this work opens the perspective to use these molecules as ‘leads’ for the design of novel and selective drug candidates for some tropical infectious diseases. 相似文献
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9.
Dr. Christoph Kieninger Dr. Klaus Wurst Dr. Maren Podewitz Dr. Maria Stanley Dr. Evelyne Deery Dr. Andrew D. Lawrence Prof. Dr. Klaus R. Liedl Prof. Dr. Martin J. Warren Prof. Dr. Bernhard Kräutler 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20304-20311
The (formal) replacement of Co in cobalamin ( Cbl ) by NiII generates nibalamin ( Nibl ), a new transition-metal analogue of vitamin B12. Described here is Nibl , synthesized by incorporation of a NiII ion into the metal-free B12 ligand hydrogenobalamin ( Hbl ), itself prepared from hydrogenobyric acid ( Hby ). The related NiII corrin nibyric acid ( Niby ) was similarly synthesized from Hby , the metal-free cobyric acid ligand. The solution structures of Hbl , and Niby and Nibl , were characterized by spectroscopic studies. Hbl features two inner protons bound at N2 and N4 of the corrin ligand, as discovered in Hby . X-ray analysis of Niby shows the structural adaptation of the corrin ligand to NiII ions and the coordination behavior of NiII. The diamagnetic Niby and Nibl , and corresponding isoelectronic CoI corrins, were deduced to be isostructural. Nibl is a structural mimic of four-coordinate base-off Cbls , as verified by its ability to act as a strong inhibitor of bacterial adenosyltransferase. 相似文献
10.
Matthew J. Haines Stanley R. Huddy 《International Journal of Mathematical Education in Science & Technology》2013,44(4):598-611
We consider the effect of constraints on the number of non-negative integer solutions of x+y+z = n, relating the number of solutions to linear combinations of triangular numbers. Our approach is geometric and may be viewed as an introduction to proofs without words. We use this geometrical perspective to prove identities by counting the number of solutions in two different ways, thereby combining combinatorial proofs and proofs without words. 相似文献