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Increased demand for higher spectrum efficiency, especially in the space-limited chip, base station, and vehicle environments, has spawned the development of full-duplex communications, which enable the transmitting and receiving to occur simultaneously at the same frequency. The key challenge in this full-duplex communication paradigm is to reduce the self-interference as much as possible, ideally, down to the noise floor. This paper provides a comprehensive review of the self-interference cancellation (SIC) techniques for co-located communication systems from a circuits and fields perspective. The self-interference occurs when the transmitting antenna and the receiving antenna are co-located, which significantly degrade the system performance of the receiver, in terms of the receiver desensitization, signal masking, or even damage of hardwares. By introducing the SIC techniques, the self-interference can be suppressed and the weak desired signal from the remote transmitter can be recovered. This, therefore, enables the full-duplex communications to come into the picture. The SIC techniques are classified into two main categories: the traditional circuit-domain SICs and the novel field-domain SICs, according to the method of how to rebuild and subtract the self-interference signal. In this review paper, the field-domain SIC method is systematically summarized for the first time, including the theoretical analysis and the application remarks. Some typical SIC approaches are presented and the future works are outlooked.

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aims: Under suboptimal storage and transport conditions, influenza virus (flu-v) RNA is prone to degradation and lysis buffers from RNA extraction kits have a potential to stabilize RNA. The aim of this study was to investigate the effects of different lysis buffers on the stability of flu-v RNA. Materials & methods: Aliquots of flu-v suspension were processed in parallel with two lysis buffers, and then underwent cyclic freeze-thaw or prolonged storage at 4, 22 and -20°C. The viral RNA was analyzed by using real-time and conventional RT-PCR amplifying, respectively, partial and full-length sequences of the flu-v matrix gene. Results: The viral RNA remained intact in samples treated with either of the two lysis buffers for at least 7 days at 4°C, 90 days at -20°C or following seven freeze-thaw cycles, but buffer A was superior to buffer B in protecting RNA from degradation at 4°C and 22°C, or following a further increase of freeze-thaw cycles. conclusion: Lysis buffer preservatives provide viral RNA stabilization, whereas different lysis buffers vary in their ability to stabilize viral RNA, and thus their performance characteristics should be evaluated prior to their application in clinical practice. KeywordsNucleic acid (NA)-based techniques are now widely used in influenza surveillance and diagnosis [1,2]. However, suboptimal storage and transport conditions of influenza virus (flu-v) samples will most likely result in viral RNA degradation [3][4][5], and in some settings it is difficult to ensure certain sample conditions required by WHO, such as ultra-low-temperature freezing, especially for resource-limited areas; consequently, the efficacy of the NA-based assays will be compromised. Thus, inexpensive, simple and efficient sample stabilization methods need to be developed for facilitating flu surveillance and diagnosis.Earlier studies have shown that lysis buffers of NA extraction kits have the potential to be used as RNA stabilization agents at adverse temperatures and over an extended period of time [6,7], and have potential to inactivate viruses completely [8], which would reduce the biohazard risk from sample leakage during transit and simplify transportation requirements while preserving the integrity of viral RNA before testing. Nevertheless, these studies did not give a comprehensive picture of the abilities of lysis buffers in protecting viral RNA from degradation and there are still some questions that remain unanswered. First, could intact viral RNA be recovered from the samples preserved in lysis buffer at adverse temperatures and over an extended period of time, considering that a real-time RT-PCR (rRT-PCR) targeting a shorter fragment was only employed to evaluate the presence, quantity and/or quality of viral RNA in these studies [6,7]? Second, what is the consequence of virus samples preserved in lysis buffer and subjected to repeated freeze-thaw cycles, For reprint orders, please contact: reprints@futuremedicine.com

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Two infinite complexes {[Cu2(O2CCH3)4](3-tpt)(CH3OH)2}∞ (1) and {[Cu2(O2CPh)4](3-tpt)(C6H6)1.5}∞ (2) were obtained by reactions of 2,4,6-tris(3′-pyridyl)-1,3,5-triazine (3-tpt) with Cu2(O2CCH3)4 and Cu2(O2CPh)4, respectively, which have been structurally established by single-crystal X-ray diffraction. Complex (1) consists of one-dimensional zig-zag chains in its solid state, which can encapsulate methanol molecules; complex (2) consists of one-dimensional helical chains in its solid state, providing large channels which can selectively enclathrate benzene molecules. (1) crystallizes in the monoclinic space group P21/c with a 8.2892(4), b 22.8479(8), c 16.9258(10) Å, β 99.1480(10)°, V 3164.8(3) Å3, and Z 4; (2) crystallizes in the triclinic space group P1 with a 10.7641(8), b 12.0908(8), c 18.9039(12) Å, α 82.514(3)°, β 85.268(2)°, γ 79.746(4)°, V 2395.9(3) Å3, and Z 2. The inclusion selectivity toward aromatic molecules was discussed.

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Background: When any equipment is running, the physical collision occurs in the machinery, which requires the hydraulic buffer devices to absorb and dissipate the impact energy in order to avoid the large vibration and even the damage to the structure caused by the impact load on the equipment. Therefore, the design of hydraulic buffers is very necessary. Objective: Through the analysis of the research status of hydraulic buffers, some valuable conclusions are extracted from the representative and prospective results to predict the future research and development direction of hydraulic buffers. Methods: The researches on hydraulic buffers are summarized and compared, and the characteristics of energy absorption and energy consumption of hydraulic buffers are expounded. Combined with the principle of hydraulic buffers, the related patents of hydraulic buffer are studied. Results: By tracing the characteristics of different types of hydraulic buffers, the main problems existing in the development of hydraulic buffers are analyzed, such as short working life, low energy absorption efficiency, etc. Solving such problems as a prerequisite, the patents’ development of the structure and design method of hydraulic buffers is prospected. Conclusion: The optimization and development of hydraulic buffers are conducive to improving the energy absorption efficiency and frequency of hydraulic buffers. This paper, thus, summarizes the advantages and disadvantages of different kinds of hydraulic buffers by tracing and summarizing the previous patents, learning that the most widely used buffer is the porous hydraulic buffer, but the cushioning performance of core rod buffer is more, which is the main development trend in the future.