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Utilization of Freon-type methanes as functional one-carbon synthons in the synthesis of various deuterated indoline alkaloids was demonstrated here. A series of halomethyl radicals were generated from electro-reductive C-X cleavage of Freon-type methanes and captured efficiently by acrylamides to provide various halogenated oxindoles

With the advent of the information age, big data put forward higher requirements for capacity of storage devices. Compared with the method of reducing the size of the device to enhance the integration level, the high density storage of increasing the memory state of the single device will be very beneficial to solving the problem. In this work, we propose an idea of two-parameter and multi-state memory device involved in both resistance and capacitance operation levels. At first, a new donor-acceptor (D-A)-type copolymer is designed and synthesized. Then, the memory device of Al/copolymer/ITO structure is fabricated, and the current-voltage (I-V) and capacitance-voltage (C-V) curves are measured by a KEITHLEY 4200 semiconductor characterization system. The device not only displays the obvious memory resistance characteristics, but also has the memory capacitance behavior in single resistance state, which results in two resistance states and four capacitance states, so that the device has the capability of two-parameter and multi-state memory. In addition, the device shows more capacitance states after the switching behavior has been modulated by the voltage amplitude, which provides an effective method to control the memory states. In order to study the conductive mechanism of the device, we test the relationship between resistance and temperature. It is found that the resistance decreases with the increase of temperature, indicating that the device has the obvious semiconductor properties. Furthermore, the fitting results of I-V data show that the mechanism of resistance switching is in good consistence with the classical trap-controlled space charge limited current theory. The capacitance switching in single resistance state is closely related to the polarization characteristic of D-A structure in the copolymer film. The polarization force microscopy phase image shows that the copolymer film has obvious polarization and depolarization characteristics under the external electric field. Based on the polarization characteristics of copolymer, the correlation between memory resistance and memory capacitance is established by introducing a polarization operator of molecules, and the matrix model describing the two-parameter and multi-state memory characteristics is given. The above results show that the multi-state memory characteristics will store more information than 2-bits mode in a single cell, which will provide a reference for improving the storage density of information.

Recurrent spontaneous abortion (RSA), defined as three or more sequential abortions before the twentieth week of gestation. Some studies have led to the awareness that immunological factors play an important role in establishing a successful pregnancy. The aim of present study was to investigate the relationship between RSA and polymorphisms of cytokine genes coding for TNF-α (-308 G→A, -238 G→A), TNF-β (+252 G→A) as Th1 or pro-inflammatory factors as well as IL-6 (-634 G→C, -174 G→C), IL-10 (-1082 A→G, -819 C→T, -592C→A) as Th2 cytokines in women with RSA compared with healthy women. A total of 284 women with RSA and 284 control women with at least two successful pregnancies and no history of abortion were included in the study. The polymerase chain reaction (PCR), allele-specific oligonucleotide polymerase chain reaction (ASO-PCR) or PCR-RFLP (restriction fragment length polymorphism) methods were used for genotyping. In addition, the ELISA was conducted to investigate four cytokine serum levels in women with RSA and healthy women. Results showed that: TNF-α -308G/A, IL-6 -174 G/C and IL-10 -819 G/C polymorphisms showed statistically significant differences between the RSA patients and controls (P=0.008, P=0.0005 and P=0.03 separately). Levels of four cytokines in the serum showed that there were no significant differences in TNF-α and TNF-β between patients and control (P>0.05), while the level of IL-6 and IL-10 were lower than control group and the differences were statically significant (P