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Myeloid Derived Suppressor Cells (MDSCs) play important roles in constituting the immune suppressive environment promoting cancer development and progression. They are consisted of a heterogeneous population of immature myeloid cells including polymorphonuclear MDSC (PMN-MDSC) and monocytes MDSC (M-MDSC) that are found in both the systemic circulation and in the tumor microenvironment (TME). While previous studies had shown that all-trans retinoic acid (ATRA) could induce MDSC differentiation and maturation, the very poor solubility and fast metabolism of the drug limited its applications as an immune-modulator for cancer immunotherapy. We aimed in this study to develop a drug encapsulated liposome formulation L-ATRA with sustained release properties and examined the immuno-modulation effects. We showed that the actively loaded L-ATRA achieved stable encapsulation and enabled controlled drug release and accumulation in the tumor tissues. In vivo administration of L-ATRA promoted the remodeling of the systemic immune homeostasis as well as the tumor microenvironment. They were found to promote MDSCs maturation into DCs and facilitate immune responses against cancer cells. When used as a single agent treatment, L-ATRA deterred tumor growth, but only in immune-competent mice. In mice with impaired immune functions, L-ATRA at the same dose was not effective. When combined with checkpoint inhibitory agents, L-ATRA resulted in greater anti-cancer activities. Thus, L-ATRA may present a new IO strategy targeting the MDSCs that needs be further explored for improving the immunotherapy efficacy in cancer.

Previous studies have revealed changed functional connectivity patterns between brain areas in chess players using resting-state functional magnetic resonance imaging (rs-fMRI). However, how to exactly characterize the voxel-wise whole brain functional connectivity pattern changes in chess players remains unclear, which could provide more convincing evidence for establishing the relationship between long-term chess practice and brain function changes. In this study, we employed newly developed whole brain functional connectivity pattern homogeneity (FcHo) method to identify the voxel-wise changes of functional connectivity patterns in 28 chess master players and 27 healthy novices. Seed-based functional connectivity analysis was used to identify the alteration of corresponding functional couplings. FcHo analysis revealed significantly increased whole brain functional connectivity pattern similarity in anterior cingulate cortex (ACC), anterior middle temporal gyrus (aMTG), primary visual cortex (V1), and decreased FcHo in thalamus and precentral gyrus in chess players. Resting-state functional connectivity analyses identified chess players showed decreased functional connections between V1 and precentral gyrus. Besides, a linear support vector machine (SVM) based classification achieved an accuracy of 85.45%, a sensitivity of 85.71% and a specificity of 85.19% to differentiate chess players from novices by leave-one-out cross-validation. Finally, correlation analyses revealed that the mean FcHo values of thalamus were significantly negatively correlated with the training time. Our findings provide new evidences for the important roles of ACC, aMTG, V1, thalamus and precentral gyrus in chess players and indicate that long-term professional chess training may enhance the semantic and episodic processing, efficiency of visual-motor transformation, and cognitive ability.

Unmanned aerial vehicles (UAVs) have tremendous potential to improve wireless network capacity, but are challenging to operate in ultra-dense networks, mainly due to the strong interference received from the dominated lineof- sight channels of the UAVs. By forming multiple highly directional beams, millimeter-wave (mmWave) communication technology allows concurrent user transmissions via beam-division multiple access (BDMA), and thus has emerged as a promising solution to mitigate interference for the fifth generation (5G) UAV communication. However, due to the limited number of beams generated in practical mmWave communication systems, conventional BDMA cannot meet the ever increasing capacity requirement. A new multiple access technique is intensely desired. In this article, we integrate mmWave communication with UAV-aided 5G ultra-dense networks, and design a novel link-adaptive constellation- division multiple access (CoDMA) technique. We discuss key challenges in efficient multiple access technique design, and then investigate design principles on new multiplexing methods and beamwidth optimization for interference management in UAV-aided dynamic networks. We further apply flexible constellation division in rateless codes, and put forward the system-level design of CoMDA with beamwidth adaptation to unleash the multiplexing gain. Finally, we show that our design can successfully enable multiple-user access within a single beam without causing any intra-beam interference while efficiently mitigating interference from adjacent beams. We also demonstrate that the proposed design is adaptive to the UAV network dynamics, and can greatly improve the system throughput.

An outstanding chess player needs to accumulate massive visual and spatial information for chess configurations. Visual motion area (MT) is considered as a brain region specialized for visual motion perception and visuospatial attention processing. However, how long-term chess training shapes the functional connectivity patterns of MT, especially its functional subregions, has rarely been investigated. In our study, using resting-state functional connectivity (RSFC) and Granger causality analysis (GCA), we studied the changed functional couplings of MT subregions between 28 chess master players and 27 gender- and age-matched healthy novices to reveal the neural basis of long-term professional chess training. RSFC analysis identified decreased functional connections between right dorsal-anterior subregion (CI1.R) and left angular gyrus, and increased functional connections between right ventral-anterior MT subregion (CI2.R) and right superior temporal gyrus in chess experts. Moreover, GCA analyses further found increased mutual interactions of left angular gyrus and CI1.R in chess experts compared to novice players. These findings demonstrate that long-term professional chess training could enhance spatial perception and reconfiguration and semantic processing efficiency for superior performance.

A pulsation measurement algorithm was presented in this study, by using the phase-based method to visualize ocular pulse in the anterior chamber of healthy eyes. The algorithm mainly tracks the relative displacement between the cornea and lens by extracting the phase difference between adjacent images separated by 5 ms time intervals. The anterior chamber structural image in vivo is achieved by full-range, complex spectral domain, optical coherence tomography (FRC SD-OCT). Phase tracking was performed on a total of 1000 images within 5 s. In order to eliminate the noise phase caused by human motion during the acquisition process, the high-order phase compensation algorithm was used to eliminate the phase motion of large tissues. The frequency of the phase change in the relative motion after the noise subtraction was 1.2 Hz. Comparing with the heart beat measured by a finger pulse oximeter at the same time, the frequency of the phase change was consistent with the heart beat frequency. This measurement technique can be used to evaluate the biomechanical properties of ocular tissue and has a positive effect on the pathological studies of glaucoma.

The retinal nerve fiber layer (RNFL) evaluation is becoming a very effective method for the clinical diagnosis of early glaucoma. The purpose of this paper is to extract the pulsations of the RNFL, which might be used as a novel biomarker for glaucoma diagnosis. To demonstrate that the optical coherence tomography (OCT) could extract the subtle RNFL dynamic pulsatile motion in normal eyes in vivo, the subjects’ retina was imaged by spectral domain optical coherence tomography (SD-OCT) based on histogram RNFL pulse extraction algorithm. Firstly, B-scan images of multiple retinal layers in normal subjects were acquired. The RNFL was identified from each B-scan with a segmentation algorithm based on shortest path and convolutional neural network. Secondly, a histogram-based RNFL pulsation extraction algorithm was proposed to track the displacement of the RNFL which is based on the acquired RNFL B-scan images. Finally, in evaluating the dynamic pulse signal extracted from the pulsating motion of RNFL, an experiment was designed to collect heart rate using an infrared pulse sensor device. The cardiac pulse waveform and the RNFL pulse waveform were compared and analyzed in time and frequency domain. The results show that the extracted RNFL pulse has the same frequency as the cardiac pulse, which validate the feasibility and accuracy of the in vivo extraction scheme used in this paper.

UAV aided communication technology holds tremendous potential to upgrade outdoor link throughput and provide on-demand wireless services. The flexible deployment characteristic makes UAV-aided networks competent at emergency situations, including natural disasters and sudden traffic hotspots. In this backdrop, UAVs are required to be densely deployed to accommodate the huge volume of data traffic, where interference amid the neighboring cells turns out to be extremely challenging. To break this stalemate, this article systematically investigates spectrum sharing technology for ultra-dense UAV-aided networks from the architecture level down to the physical layer. We shed light on design principles and key challenges in utilizing overlapped spectrum for interference-enabled concurrent transmissions. With these principles in mind, we introduce SpecShare, which utilizes coding redundancy at the PHY layer for UAV spectrum sharing. We explore the optimal UAV placement strategy in the network layer to fully unleash the potential of such spectrum sharing capacity. We discuss the feasibility of SpecShare, and demonstrate its effectiveness in terms of network throughput.

A room-temperature photochemical method was introduced to fabricate SnO 2 -reduced graphene oxide (SnO 2 -rGO) composite with a new type of structure. SnO 2 dense layers were directly grown on the two sides of an rGO sheet through ultraviolet light (UV) irradiation of a mixed precursor solution of SnSO 4 , H 2 SO 4 , and graphene oxide for 6 h. The composite possessed a novel flat flake-like structure consisting of two SnO 2 dense layers and an rGO sheet sandwiched in between. In contrast to most graphene-based composites, the fabricated composite was non-flexible, wrinkle-free and rGO surfaces were completely covered. The composite could be used in photocatalysis and exhibited remarkably enhanced activity in degradation of p -nitrophenol under low intensity of UV light or sunlight. The activity was more than 12 times that of pure SnO 2 and considerably higher than that of other SnO 2 -rGO composites. The dense layer immobilized the flat structure, promoted the photocatalytic activity, and maintained the long-term stability of the composite. After preservation of more than 12 months in ambient condition, the composite showed a nearly constant activity. This photochemical method can be used to fabricate graphene-based composites with regular structure, high performance, and long-term stability.

For the construction of a resistive-type gas-sensor, it is usually required for a sensing film to be fabricated on a non-conductive substrate. The in situ construction of a sensor by subjecting the substrate to an electrodeposition method is impossible and there have been no related reports on this. Herein, taking the in situ construction of a SnO2 film sensor as an example, a novel electrodeposition-based method was introduced. A conductive graphite coating was firstly fabricated on the non-conductive substrate for the implementation of the electrodeposition, and then a calcining process was employed. The conductive pristine graphite coating was found to become non-conductive after being calcined for more than 70 min at 500 °C, resulting in the final electrodeposited film being able to work as a sensing film. Some important parameters related to the sensing performances, including the formation, the conductivity, the electrodeposition time, the calcining time and the working temperature, were systematically studied. Under the optimal conditions, the SnO2 film sensor exhibited high sensitivity, a fast response and recovery, and long-term stability in the detection of ethanol gas with concentrations ranging between 1–100 ppm. The electrodeposition-based method is reproducible, mass-productive and general. It is therefore practical and promising for the construction of various semiconductor film sensors.

Atmospheric humidity is one of the most important environmental attributes for weather condition. It affects the economy of nature as well as human life. Many environmental processes are affected by this attribute. For example, rice has the most powerful photosynthesis when the atmospheric humidity is in between 50% and 60%. For most of the human being, the humidity in between 20% and 80% is good to have a healthy life. Consequently, humidity measurement methods are urgently required. The existing methods are neither convenient for large scale deployment due to the high cost nor accurate enough to use. Recently, researchers found that humidity has a direct effect on radio propagation. This observation is undoubtedly useful to measure humidity in the environment. However, the humidity estimation based on received signal strength indicator (RSSI) is easily affected by the temporal and spatial variance due to multipath effect. Meanwhile, the change of radio signals incurred by RSSI-based systems is not that much obvious when the transmitter and receiver are in close distance. As a result, it is challenging to measure humidity in indoor environments. In this work, we provide a novel system, namely WiHumidity, to tackle this problem. The system utilizes the special diversity of channel state information (CSI) to alleviate multipath effect at the receiver. Extensive experiments have been conducted to verify the effectiveness of WiHumidity. The experimental results verify that on average, WiHumidity can achieve 79% measurement accuracy.

A new general method for the fabrication of a reduced graphene oxide (rGO)-based ordered monolayer macroporous film composed of a layer of closely arranged pores is introduced. Assisted by the polystyrene microsphere monolayer colloid crystal by a simple solution-heated method, pure rGO, rGO-SnO2, rGO-Fe2O3, and rGO-NiO composite monolayer ordered porous films were examplarily constructed on the curved surface of a ceramic tube widely used in gas sensors. The rGO-oxide composite porous films could exhibit much better sensing performances than those of the corresponding pure oxide films and the composite films without the ordered porous structures in detecting ethanol gas. The enhancement mechanisms induced by distinctive rGO-oxide heterojunctions and porous structures as well as the effects of the rGO content and the pore-size on the sensitivity of the composite films were systematically analyzed and discussed. This study opens up a kind of construction method for an rGO-based composite film gas sensor with uniform surface structures and high performance.

A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2. The growing and the as-formed SnO2, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO2-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties.

A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2. The growing and the as-formed SnO2, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO2-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties.