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Fengjiao Yao, Yacong An, Xundou Li, Zhaoyi Li, Jinhong Duan, Xian-Da Yang Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of ChinaCorrespondence: Xian-Da Yang Email ayangmd@hotmail.comPurpose: Chemotherapy is the primary treatment for advanced colon cancer, but its efficacy is often limited by severe toxicities. Targeted therapy in the form of selectively drug delivery system (SDDS) is an important strategy to reduce adverse effects. Here, we aim to design a novel SDDS with potential for practical application using biocompatible components and scalable production process, for targeted delivery of doxorubicin (Dox) to colon cancer cells.Methods: The SDDS was made of a self-assembled DNA nano-cross (Holliday junction, or HJ) functionalized by four AS1411 aptamers (Apt-HJ) and loaded with Dox.Results: Apt-HJ had an average size of 12.45 nm and a zeta potential of − 11.6 mV. Compared with the monovalent AS1411 aptamer, the quadrivalent Apt-HJ showed stronger binding to target cancer cells (CT26). A complex of Apt-HJ and doxorubicin (Apt-HJ-Dox) was formed by intercalating Dox into the DNA structure of Apt-HJ, with each complex carrying approximately 17 Dox molecules. Confocal microscopy revealed that Apt-HJ-Dox selectively delivered Dox into CT26 colon cancer cells but not the control cells. Moreover, Apt-HJ-Dox achieved targeted killing of CT26 cancer cells in vitro and reduced the damage to control cells. Importantly, compared with free Dox, Apt-HJ-Dox significantly enhanced the antitumor efficacy in vivo without boosting the adverse effects.Conclusion: These results suggest that Apt-HJ-Dox has application potential in targeted treatment of colon cancer.Keywords: colon cancer, targeted therapy, aptamer, holliday junction, doxorubicin

We explored the effect of psychological contract breach on employees' unethical behavior and examined the mediating and moderating roles of organizational disidentification and organizational ethical climate, respectively, using data from 362 paired questionnaires. The results of multiple linear regression analysis showed that psychological contract breach was positively related to employees' unethical behavior and also that organizational disidentification completely mediated the relationship between psychological contract breach and employees' unethical behavior. In addition, organizational ethical climate moderated the relationship between psychological contract breach and employees' unethical behavior by weakening the mediating role of organizational disidentification. The results demonstrated that avoidance of organizational disidentification and cultivation of a higher level of organizational ethical climate were conducive to the reduction of employees' unethical behavior.

This paper proposed an effective interference alignment algorithm based on channel state feedback concentration (FCIA) for device-to-device (D2D) communications. The algorithm iteratively calculates the precoding matrix by using the global channel state information. Furthermore, as D2D discovery is the premise of the D2D communications, an effective interference alignment algorithm based on D2D discovery is also proposed. Simulation results show that, the proposed FCIA algorithm reduces the feedback overhead for transmission coordination compared with the existing full feedback based algorithm. The proposed interference alignment scheme based on D2D discovery feedback is compared with the existing D2D discovery scheme: it is found that although the discovery time slots has increased by about 6.2%, the sum rate achieved by interference alignment is improved by almost 50%.

Background. Chemotherapy-induced peripheral neuropathy (CIPN) remains as a big unsolved challenge for cancer patients and oncologists. However, there is no effective treatment to prevent and cure it. This systematic review and meta-analysis chiefly aimed to assess the effectiveness and safety on the method of activating blood and dredging collaterals in traditional Chinese medicine (TCM) for reducing CIPN. Methods. Two authors comprehensively searched all the randomized controlled trials (RCTs) via PubMed, Cochrane, China National Knowledge Infrastructure (CNKI), and Wanfang Database of China Science Periodical Database (CSPD). The Review Manager (RevMan) 5.0 was used to conduct the meta-analysis. Results. 20 trials including 1481 participants were analyzed. 15 trials tested the incidence of all-grade CIPN which was significantly lower in intervention arm and 16 trails presented that the result of high-grade CIPN was the same. The total effective rate of the use of Chinese herbs was 77.19% versus 45.79% in the comparator group. Besides, the use of Chinese herbs statistically promoted the sensory nerve conduction velocity (SNCV) and the motor nerve conduction velocity (MNCV). Besides, the quality of life (QoL) in the intervention group was better than the comparator one. Herbs-related adverse events were skin allergy, skin chap, and scald, which could be managed well. Conclusions. The work involving studies of the effectiveness and safety on TCM for reducing CIPN proves to be encouraging. Herbs with the function of activating blood and dredging collaterals were found to potentially promote the curative effects as well as making improvements of SNCV and MNCV. However, in the future, more double-blind, multicenter, large-scale RCTs and more comprehensive researches are still required.

Metasurfaces, a new class of artificial media attracting great research interest, are composed of a two-dimensional ensemble of designer optical antennas arranged with subwavelength separation that introduce spatially-varying optical properties (e.g., amplitude, phase and polarization). By engineering the subwavelength optical antennas and integrating with functional materials, metasurfaces can manipulate light at one’s will and have led to the demonstration of many exotic electromagnetic phenomena. Metasurfaces have the potential to replace bulky optical components and devices as they are ultra-thin (subwavelength thickness), light weight, and able to provide new functionalities and overcome the limitations of their conventional counterparts. There are a number of promising areas in fundamental research and practical applications where metasurfaces could have a significant impact. In this dissertation, I studied the fundamental physics of the strong interaction between light and metasurfaces and explored passive and active nanophotonic devices based on metasurfaces. I demonstrated metasurface-based devices showing record-breaking or completely novel functionalities; these devices include optical modulators for dynamic control of light propagating in free space over an unprecedented broad wavelength range, photonic integrated devices with record-small footprints, and metasurface sensors orders of magnitude more sensitive than the state-of-art sensing techniques. Strongly correlated perovskites possess widely tunable electronic structure that can host a variety of phases. Nickelates, in particular, undergo electric-field-tunable phase transitions with dramatic changes in the optical properties. In Chapter 2, I will describe my discovery of a new optical phase-transition material SmNiO3 and experimental demonstration of strong optical modulation utilizing the large and non-volatile optical refractive index change associated with electron-doping induced phase transition of SmNiO3. Large electrical modulation of light over a broad wavelength range, from the visible to the mid-infrared,  = 0.4 m – 17 m, is demonstrated using thin-film SmNiO3. By integrating SmNiO3 and plasmonic metasurface structures, modulation of a narrow band of light that resonantly interacts with the metasurfaces is realized. Furthermore, solid-state electro-optic modulators are demonstrated by integrating SmNiO3 and solid polymer electrolytes. Correlated perovskites with tunable and non-volatile electronic phases create a new platform for active photonic devices, such as optoelectronic modulators, electrically programmable optical memories, smart windows, and variable emissivity coatings. Research on metasurfaces has so far focused on controlling wavefronts of light propagating in free space, and the implication of metasurfaces on integrated photonics has not been explored. I conducted initial work on using metasurfaces to control light propagation on a chip. In chapter 3, I will show that gradient metasurface structures consisting of phased arrays of plasmonic or dielectric nano-antennas provide a platform to control guided waves via strong optical scattering at subwavelength intervals. Such gradient metasurfaces enable the creation of small-footprint, broadband, and low-loss photonic integrated devices. I will describe experimental demonstration of waveguide mode converters, polarization rotators, and asymmetric optical power transmission in waveguides patterned with plasmonic gradient metasurfaces. I will also describe experimental demonstration of all-dielectric on-chip polarization rotators that are based on phased arrays of Mie resonators and have negligible insertion losses. Metasurfaces emerge as a new promising photonic platform for biosensing because they offer strong optical confinement and tunable optical resonances. In chapter 4, I will show that metasurface-based biosensors consisting of gold nano-antenna arrays loaded with graphene and working in the mid-infrared spectral range can achieve simultaneous high-sensitivity and high-specificity detection of biomolecules. The biosensors support a hybrid plasmon-phonon resonant mode that concentrates incident light into deeply subwavelength optical spots with local light intensity enhancement by a factor of 104. Strong light-molecule interactions in these optical spots allow for determing protein molecule concentrations via spectral shifts of the plasmon-phonon resonance. A combination of passive and active tuning of the metasurface sensors allows for spectrally overlapping the plasmon-phonon resonance and the vibrational modes of protein molecules, so that I can identify protein molecules via their characteristic mid-infrared “fingerprints”. The high sensitivity and specificity of the metasurface sensors enable the detection of the secondary structure of protein immunoglobulin (IgG) molecules with a sensitivity four orders of magnitude higher than that of conventional attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR).