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The power of natural evolution lies in the adaptability of biological organisms but is constrained by the time scale of genetics and reproduction. Engineering artificial molecular machines should not only include adaptability as a core feature but also apply it within a larger design space and at a faster time scale. A lesson from engineering electromechanical robots is that modular robots can perform diverse functions through self-reconfiguration, a large-scale form of adaptation. Molecular machines made of modular, reconfigurable components may form the basis for dynamic self-reprogramming in future synthetic cells. To achieve modular reconfiguration in DNA origami assemblies, we previously developed a tile displacement mechanism in which an invader tile replaces another tile in an array with controlled kinetics. Here, we establish design principles for simultaneous reconfigurations in tile assemblies using complex invaders with distinct shapes. We present toehold and branch migration domain configurations that expand the design space of tile displacement reactions by two orders of magnitude. We demonstrate the construction of multitile invaders with fixed and variable sizes and controlled size distributions. We investigate the growth of three-dimensional (3D) barrel structures with variable cross sections and introduce a mechanism for reconfiguring them into 2D structures. Last, we show an example of a sword-shaped assembly transforming into a snake-shaped assembly, illustrating two independent tile displacement reactions occurring concurrently with minimum cross-talk. This work serves as a proof of concept that tile displacement could be a fundamental mechanism for modular reconfiguration robust to temperature and tile concentration.

DNA-based neural networks are a type of DNA circuit capable of molecular pattern recognition tasks. Winner-take-all DNA networks have been developed to scale up the complexity of molecular pattern recognition with a simple molecular implementation. This simplicity was achieved by replacing negative weights in individual neurons with lateral inhibition and competition across neurons, eliminating the need for dual-rail representation. Here we introduce a new type of DNA circuit that is called loser-take-all: an output signal is ON if and only if the corresponding input has the smallest analog value among all inputs. We develop a DNA strand-displacement implementation of loser-take-all circuits that is cascadable without dual-rail representation, maintaining the simplicity desired for scalability. We characterize the impact of effective signal concentrations and reaction rates on the circuit performance, and derive solutions for compensating undesired signal loss and rate differences. Using these approaches, we successfully demonstrate a three-input loser-take-all circuit with nine unique input combinations. Complementary to winner-take-all, loser-take-all DNA circuits could be used for recognition of molecular patterns based on their least similarities to a set of memories, allowing classification decisions for patterns that are extremely noisy. Moreover, the design principle of loser-take-all could be more generally applied in other DNA circuit implementations including k-winner-take-all.

A Gram-positive, cellulose-degrading actinobacterium, designed strain NEAU-YM18T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) sampled in Langfang, Hebei Province, PR China. The novel strain was characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed that strain NEAU-YM18T belonged to the genus Catellatospora . Cells of strain NEAU-YM18T were observed to contain meso- and 3-hydroxy-diaminopimelic acids as diagnostic cell-wall amino acids. The acyl type of the cell-wall muramic acid was glycolyl. The whole-cell hydrolysates were xylose, glucose and ribose. The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were iso-C15 : 0, iso-C16 : 0, C18 : 1 ω9c and summed feature 5 (anteiso-C18 : 0/C18 : 2 ω6,9c). The menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The DNA G+C content was 71.1 %. The results of 16S rRNA gene sequence and phylogenetic analyses indicated that strain NEAU-YM18T was closely related to Catellatospora chokoriensis 2-25(1)T (98.4 % 16S rRNA gene sequence similarity), Catellatospora vulcania NEAU-JM1T (98.3%) and Catellatospora sichuanensis H14505T (98.3 %) and formed a branch with C. sichuanensis H14505T. Furthermore, the whole genome phylogeny of strain NEAU-YM18T showed that the strain formed an independent clade. The digital DNA–DNA hybridization results between NEAU-YM18T and C. chokoriensis 2-25(1)T, C. vulcania NEAU-JM1T and C. sichuanensis H14505T were 25.0, 24.7 and 24.7 %, respectively, and the whole-genome average nucleotide identity values between them were 81.5, 81.4 and 81.4 %, respectively. These genetic results and some phenotypic characteristics could distinguish strain NEAU-YM18T from its reference strains. In addition, genomic analysis confirmed that strain NEAU-YM18T had the potential to decompose cellulose and produce bioactive compounds. Therefore, strain NEAU-YM18T represents a novel species of the genus Catellatospora , for which the name Catellatospora tritici sp. nov. is proposed. The type strain is NEAU-YM18T (=CCTCC AA 2020040T=JCM 33977T).

A novel cellulase-producing actinobacterium, designated strain NEAU-L178T, was isolated from soil sample collected from Qiqihaer, Heilongjiang Province, PR China. A polyphasic study was carried out to determine the taxonomic status of the strain. On the basis of 16S rRNA gene sequence analysis, strain NEAU-L178T should be classified into the genus Nonomuraea and is closely related to Nonomuraea cavernae SYSU K10005T (99.31 % 16S rRNA gene sequence similarity), Nonomuraea glycinis NEAU-BB2C19T (98.75 %), Nonomuraea guangzhouensis NEAU-ZJ3T (98.75 %) and ‘Nonomuraea rhizosphaerae’ NEAU-mq18T (98.34 %). The digital DNA–DNA hybridization values between them are 27.1, 26.1, 42.0 and 30.9 %, and the whole-genome average nucleotide identity values between them are 83.1, 82.3, 90.3 and 85.8 %, respectively. The whole-cell hydrolysates contained glucose, ribose, arabinose and madurose. The menaquinones were identified as MK-9(H0), MK-9(H4) and MK-9(H2). The major fatty acids were C16 : 0, iso-C17 : 0 and C17 : 0 10-methyl. The detected polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylinositol and three unidentified phospholipids. The genomic DNA G+C content was 69.7 mol%. In addition, whole-genome analysis indicated that strain NEAU-L178T had the potential to degrade cellulose. Based on the phenotypic, genotypic, chemotaxonomic and phylogenetic data, strain NEAU-L178T can be differentiated from its close phylogenetic relatives and represents a novel species of the genus Nonomuraea , for which the name Nonomuraea aurantiaca sp. nov. is proposed. The type strain is NEAU-L178T (=JCM 34799T=CGMCC 4.7741T).

Developmental self-assembly of DNA nanostructures provides an ideal platform for studying the power and programmability of kinetically controlled structural growth in engineered molecular systems. Triggered initiation and designated sequencing of assembly and disassembly steps have been demonstrated in structures with branches and loops. Here we introduce a new strategy for selectively activating distinct subroutines in a developmental self-assembly program, allowing structures with distinct properties to be created in response to various molecular signals. We demonstrate this strategy in triggered self-assembly of a DNA ring, the size and growth direction of which are responsive to a key molecule. We articulate that reversible assembly steps with slow kinetics at appropriate locations in a reaction pathway could enable multiple populations of structures with stimulus-responsive properties to be simultaneously created in one developmental program. These results open up a broad design space for the self-assembly of molecules with adaptive behaviors toward advanced control in synthetic materials and molecular motors.

A novel actinobacterium, designated strain NEAU-7082T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) and characterized by using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed the affiliation of strain NEAU-7082T to the genus Glycomyces . 16S rRNA gene sequence analysis indicated that strain NEAU-7082T belonged to the genus Glycomyces and was closely related to Glycomyces mayteni JCM 16217T (99.0 % 16S rRNA gene sequence similarity), Glycomyces sambucus DSM 45047T (98.4 %), Glycomyces scopariae DSM 44968T (98.3 %), Glycomyces paridis DSM 102295T (98.1 %), Glycomyces artemisiae NBRC 109773T (98.0 %) and Glycomyces dulcitolivorans DSM 105121T (97.9 %). Phylogenetic analysis using the 16S rRNA gene sequence showed that the strain formed a stable clade with G. mayteni JCM 16217T and clustered with G. sambucus DSM 45047T, G. scopariae DSM 44968T, G. artemisiae NBRC 109773T and G. dulcitolivorans DSM 105121T in the genus Glycomyces . The cell wall contained meso-diaminopimelic acid and the whole-cell hydrolysates were glucose and xylose. The polar lipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), glycolipid (GL), phosphatidylinositol mannoside (PIM) and an unidentified lipid (UL). The menaquinones were MK-11(H4), MK-11 and MK-10. Major fatty acids were anteiso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. These chemotaxonomic data substantiated the affiliation of strain NEAU-7082T to the genus Glycomyces . The DNA G+C content was 71.3 mol%. A combination of DNA–DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-7082T could be distinguished from its closest relatives. Therefore, strain NEAU-7082T is considered to represent a novel species of the genus Glycomyces , for which the name Glycomyces albidus sp. nov. is proposed. The type strain is NEAU-7082T (=CCTCC AA 2019045T=JCM 33458T).

Radiotherapy is a common treatment for lung cancer. However, radiation pneumonitis caused by radiotherapy can affect the quality of life and prognosis of lung cancer patients. miR-513a-3p has been found to sensitize human lung adenocarcinoma cells to chemotherapy by targeting glutathione S-transferase P1 (GSTP1). Here, we found that x-ray induced the apoptosis of BEAS-2B and miR-513a-3p expression in a dose- and time-dependent manner, and miR-513a-3p-mimic significantly increased x-ray induced apoptosis, while miR-513a-3p-inhibitor significantly decreased x-ray induced apoptosis. Dual luciferase gene reporter system showed that miR-513a-3p targeted to inhibit the expression of GSTP1 in BEAS-2B cells. Moreover, knockdown of GSTP1 significantly increased, while overexpression of GSTP1 decreased the apoptosis of BEAS-2B induced by x-ray. Importantly, overexpression of GSTP1 significantly reduced miR-513a-3p-mimic elevated x-ray -induced apoptosis in BEAS-2B cells. In conclusion, x-ray caused increased expression of miR-513a-3p, and miR-513a-3p promoted x-ray-induced apoptosis of human lung cells by inhibiting GSTP1.

On the basis of the existing test data of high temperature mechanical properties of 1860 grade steel strands, a regression model of high temperature performance of steel strands that can be used for theoretical analysis and numerical calculation is obtained. Based on the non-stationary temperature field model in the fire of tall and large space buildings, the non-linear finite element numerical analysis method considering the time integral effect is used to establish the fire resistance numerical model of the large-span prestressed steel structure. Through the fire-resistance calculation example of Beam String Structure, the influence of different fire source positions on the fire-resistance of prestressed steel structures is discussed.

DNA catalysts are fundamental building blocks for diverse molecular information-processing circuits. Allosteric control of DNA catalysts has been developed to activate desired catalytic pathways at desired times. Here we introduce a new type of DNA catalyst that we call a cooperative catalyst: a pair of reversible reactions are employed to drive a catalytic cycle in which two signal species, which can be interpreted as an activator and an input, both exhibit catalytic behavior for output production. We demonstrate the role of a dissociation toehold in controlling the kinetics of the reaction pathway and the significance of a wobble base pair in promoting the robustness of the activator. We show near-complete output production with input and activator concentrations that are 0.1 times the gate concentration. The system involves just a double-stranded gate species and a single-stranded fuel species, as simple as the seesaw DNA catalyst, which has no allosteric control. The simplicity and modularity of the design make the cooperative DNA catalyst an exciting addition to strand-displacement motifs for general-purpose computation and dynamics.

A novel actinobacterium, designated strain NEAU-THZ27T, was isolated from soil collected from the Cornel peak in Jiaozuo, Henan Province, PR China and characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics of the strain coincided with those of members of the genus Kribbella . The results of 16S rRNA gene sequence analysis showed that strain NEAU-THZ27T belongs to the genus Kribbella and was most closely related to Kribbella podocarpi YPL1T (98.96 %), Kribbella karoonensis Q41T (98.89 %), Kribbella aluminosa HKI 0478T (98.86%) and Kribbella hippodromi S1.4T (98.85 %), similarities to other type strains of species of the genus Kribbella were found to be less than 98.7 %. Phylogenetic analyses using the 16S rRNA gene sequence and multilocus sequence analysis using the concatenated gene sequences of the gyrB, rpoB, recA, relA and atpD genes all showed that the strain formed a separate branch in the genus Kribbella . The cell wall contained ll-diaminopimelic acid as the major diamino acid and the whole-cell hydrolysates were ribose and glucose. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The predominant menaquinone was MK-9(H4). Major fatty acids were iso-C16 : 0, iso-C14 : 0 and anteiso-C15 : 0, these chemotaxonomic data supported the affiliation of strain NEAU-THZ27T to the genus Kribbella . The DNA G+C content was 68.0 mol%. Furthermore, the strain could be clearly distinguished by concatenated gene genetic distances, the combination of DNA–DNA hybridization results and some phenotypic characteristics. Therefore, it is proposed that strain NEAU-THZ27T represents a novel species of the genus Kribbella , for which the name Kribbella jiaozuonensis sp. nov. is proposed. The type strain is NEAU-THZ27T (=CGMCC 4.7504T=DSM 105535T).

BackgroundGastric cancer is one of the most common malignancies worldwide and vasculogenic mimicry (VM) is considered to be the leading cause for the failure of anti-angiogenesis therapy in advanced gastric cancer patients. Tenascin-c (TNC) plays a pivotal role in VM. Thus, we explored the role of TNC in VM formation in gastric cancer.MethodsGastric cancer tissues and corresponding adjacent tissues were collected from gastric cancer patients after surgery. We used western blot and immunohistochemistry to examine the expression of TNC in tissues and used siRNA and lentivirus to knockdown the TNC expression in gastric cancer cell lines. Then three-dimensional culturing, CCK-8, Edu assay, flow cytometry, trasnwell and pseudopodia formation assay were used to evaluate the function of TNC in gastric cancer cells and bioinformatic prediction was used to explore the mechanism underlying TNC modulating the VM in gastric cancer. Xenograft and peritoneal dissemination model were used to further explore the role of TNC in vivo.ResultsIn this study, we demonstrated that TNC was highly expressed in gastric cancer tissues and correlated with poor prognosis of gastric cancer. Furthermore, knockdown of TNC significantly inhibited VM formation and proliferation of gastric cancer cells in vitro and in vivo, with a reduction in cell migration and invasion. Mechanistically, TNC knockdown suppressed the phosphorylation of ERK and subsequently inhibited the process of EMT, both of which play an important role in VM formation. What’s more, rescue experiments showed that activation of p-ERK could reverse the suppressive role of TNC knockdown in gastric cancer cells.ConclusionsTNC plays an important role in VM formation in gastric cancer. Combining inhibition of TNC and ERK may be a potential therapeutic approach to inhibit gastric cancer growth and metastasis and decrease anti-angiogenic therapeutic resistance.

A Gram-positive, aerobic, non-motile, non-spore-forming, short rod-shaped strain, NEAU-LLCT, was isolated from cow dung in Shangzhi city, Heilongjiang Province, northeast China and identified by a polyphasic taxonomic study. Colonies was light yellow, round, with entire margin. Strain NEAU-LLCT was grown at 15–45℃ and pH 6.0–10.0. NaCl concentration ranged from 0 to 5% (W/V). The 16S rRNA gene sequence of NEAU-LLCT showed the high similarities with Microbacterium kyungheense JCM 18735T (98.5%), Microbacterium trichothecenolyticum JCM 1358T (98.3%) and Microbacterium jejuense JCM 18734T (98.2%). The whole-cell sugars were glucose, rhamnose, and ribose. The menaquinones contained MK-12 and MK-13. Ornithine, glutamic acid, lysine, and a small amount of alanine and glycine were the amino acids in the hydrolyzed products of the cell wall. The major fatty acids were iso-C16:0, iso-C18:0, anteiso-C15:0 and anteiso-C17:0. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The genome of NEAU-LLCT was 4,369,375 bp and G + C content is 70.28 mol%. A combination of DNA-DNA hybridization result and some phenotypic characteristics demonstrated that strain NEAU-LLCT could be distinguished from its closely related strains. Therefore, the strain NEAU-LLCT was considered to represent a novel specie and was named Microbacterium helvum sp. (Type strain NEAU-LLCT =CCTCC AA 2018026T = JCM 32661T).

DNA origami tilings provide methods for creating complex molecular patterns and shapes using flat DNA origami structures as building blocks. Square tiles have been developed to construct micrometer-scale arrays and to generate patterns using stochastic or deterministic strategies. Here we show triangular tiles as a complementary approach for enriching the design space of DNA tilings and for extending the shape of the self-assembled arrays from 2D to 3D. We introduce a computational approach for maximizing binding specificity in a fully symmetric tile design, with which we construct a 20-tile structure resembling a rhombic triacontahedron. We demonstrate controlled transition between 3D and 2D structures using simple methods including tile concentration, magnesium, and fold symmetry in tile edge design. Using these approaches, we construct 2D arrays with unbounded and designed sizes. The programmability of the edge design and the flexibility of the structure make the triangular DNA origami tile an ideal building block for complex self-assembly and reconfiguration in artificial molecular machines and fabricated nanodevices.

From bacteria following simple chemical gradients to the brain distinguishing complex odour information, the ability to recognize molecular patterns is essential for biological organisms. This type of information-processing function has been implemented using DNA-based neural networks, but has been limited to the recognition of a set of no more than four patterns, each composed of four distinct DNA molecules. Winner-take-all computation has been suggested as a potential strategy for enhancing the capability of DNA-based neural networks. Compared to the linear-threshold circuits and Hopfield networks used previously, winner-take-all circuits are computationally more powerful, allow simpler molecular implementation and are not constrained by the number of patterns and their complexity, so both a large number of simple patterns and a small number of complex patterns can be recognized. Here we report a systematic implementation of winner-take-all neural networks based on DNA-strand-displacement reactions. We use a previously developed seesaw DNA gate motif, extended to include a simple and robust component that facilitates the cooperative hybridization that is involved in the process of selecting a ‘winner’. We show that with this extended seesaw motif DNA-based neural networks can classify patterns into up to nine categories. Each of these patterns consists of 20 distinct DNA molecules chosen from the set of 100 that represents the 100 bits in 10 × 10 patterns, with the 20 DNA molecules selected tracing one of the handwritten digits ‘1’ to ‘9’. The network successfully classified test patterns with up to 30 of the 100 bits flipped relative to the digit patterns ‘remembered’ during training, suggesting that molecular circuits can robustly accomplish the sophisticated task of classifying highly complex and noisy information on the basis of similarity to a memory.

As the third pole of the earth, Qinghai Tibet Plateau breeds many unique species; their population size, living environment and migration process have been observed and studied by many researchers. However, these observations are mainly carried out in summer with UAVs when the temperature is high, while they are hard to work in winter since the harsh environment such as low temperature and strong wind. Here, we used a tethered balloon to observe and monitor Tibetan animals in the winter of Tibet Plateau with a long wave refrigeration infrared camera (resolution is 0.2 m@2 Km). The camera was installed on a two dimensional stable platform and was raised up to 150 m by the tethered balloon. The experiment results show that the camera on the tethered balloon can complete the observation in the harsh environment and obtain better images and videos including the mating process of two Tibetan antelopes. After this experiment, the acquired videos were used for further processing, such as motion detection and animal counting. This method can be used to observe other species occupying similar environment, such as Tibetan yak and Equus kiang.

As a common tracer in the atmosphere, airglow can be used as an important means to study the interaction between the lower atmosphere, near space, and ionosphere. In the near-Earth space, the high-altitude balloon can realize long time flight, which makes the airglow detection realize both high range resolution and time resolution. In this paper, a balloon-based multi-band airglow imager is designed, which can observe OI (557.7 nm), Na (589.3 nm), OI (630.0 nm), and OH (720–910 nm) with annular field of view (30° inner ring and 80° outer ring), and its resolution is 500 m at 250 km. The multi-band airglow imager designed in this paper is equipped in the payload cabin and raised to above 30 km for flat flying for more than 6 h. The experimental results show that the imager worked normally, and airglow images were photographed and stored; the optical system can stand the harsh environment in the near space. The multi-band airglow imager designed in this paper will take part in other near-space exploration tasks in the future and obtain corresponding results.

With the rapid development of image sensor research, mobile industry processor interface (MIPI) was used to meet the massive data throughput capacity since the higher frame rate and more pixels on the smaller sensors. This paper realized the image processing of MIPI based on FPGA. The image sensor used here is OS08A10, which has 8Mega Pixels and contains up to 4-lane MIPI serial output interface. The resolution of image sensor is 3840*2160 at frame rate of 25fps and each pixel is 10 bit, so the data throughput is 2Gbps. Since the FPGA used in this project is Spartan 6 series and it cannot deal with MIPI data directly, it is necessary to change these MIPI data into LVDS data beforehand. After receiving the processed sensor data, FPGA stores these data into DDR3 and output them through HDMI for display. The result shows that the data transmission and process of MIPI is stable and reliable which can be widely used in other MIPI sensor control.

Inflammation is a basal host defense response that eliminates the causes and consequences of infection and tissue injury. Macrophages are the primary immune cells involved in the inflammatory response. When activated by LPS, macrophages release various pro-inflammatory cytokines, chemokines, inflammatory mediators, and MMPs. However, unbridled inflammation causes further damage to tissues. Safinamide is a selective and reversible monoamine oxidase B (MAOB) inhibitor that has been used for the treatment of Parkinson's disease. In this study, we aimed to investigate whether safinamide has effects on LPS-treated macrophages. Our results show that safinamide inhibited the expression of pro-inflammatory cytokines such as IL-1α, TNF-α, and IL-6. Furthermore, safinamide suppressed the production of CXCL1 and CCL2, thereby preventing leukocyte migration. In addition, safinamide reduced iNOS-derived NO, COX-2-derived PGE2, MMP-2, and MMP-9. Importantly, the functions of safinamide mentioned above were found to be dependent on its inhibitory effect on the TLR4/NF-κB signaling pathway. Our data indicates that safinamide may exert a protective effect against inflammatory response.

The dynamic responses and load sharing features of a two-path split torque gear transmission system are investigated in this study. The possible combinations of shaft angles to ensure the gear pairs work properly are determined considering the adjacency relationship, concentric relationship, geometrical conditions and installation conditions. A dynamic model of the system considering time-varying mesh stiffness, backlash, static transmission error, stagger angle excitations and gyroscopic effects of gear body and flexible shaft is proposed. The natural characteristics of the system including natural frequencies and critical speeds are obtained. The influences of the shaft angle, asymmetric transmission error excitations and right-to-left stagger angle of double-helical gear teeth on the dynamic transmission error responses and load sharing features of the two-path split torque gear transmission system are investigated. Several references to determine the system parameters to improve the transmission property and load sharing performance of the system are provided based on the numerical simulation results.

The dynamic interactions between complex molecular structures underlie a wide range of sophisticated behaviors in biological systems. In building artificial molecular machines out of DNA, an outstanding challenge is to develop mechanisms that can control the kinetics of interacting DNA nanostructures and that can compose the interactions together to carry out system-level functions. Here we show a mechanism of DNA tile displacement that follows the principles of toehold binding and branch migration similar to DNA strand displacement, but occurs at a larger scale between interacting DNA origami structures. Utilizing this mechanism, we show controlled reaction kinetics over five orders of magnitude and programmed cascades of reactions in multi-structure systems. Furthermore, we demonstrate the generality of tile displacement for occurring at any location in an array in any order, illustrated as a tic-tac-toe game. Our results suggest that tile displacement is a simple-yet-powerful mechanism that opens up the possibility for complex structural components in artificial molecular machines to undergo information-based reconfiguration in response to their environments., Strand displacement is commonly used in DNA nanotechnology to program dynamic interactions between individual DNA strands. Here, the authors describe a tile displacement principle that is similar in concept but occurs on a larger structural level: the displacement reactions take place between DNA origami tiles, allowing reconfiguration of entire systems of interacting DNA structures.

The dynamic interactions between complex molecular structures underlie a wide range of sophisticated behaviors in biological systems. In building artificial molecular machines out of DNA, an outstanding challenge is to develop mechanisms that can control the kinetics of interacting DNA nanostructures and that can compose the interactions together to carry out system-level functions. Here we show a mechanism of DNA tile displacement that follows the principles of toehold binding and branch migration similar to DNA strand displacement, but occurs at a larger scale between interacting DNA origami structures. Utilizing this mechanism, we show controlled reaction kinetics over five orders of magnitude and programmed cascades of reactions in multi-structure systems. Furthermore, we demonstrate the generality of tile displacement for occurring at any location in an array in any order, illustrated as a tic-tac-toe game. Our results suggest that tile displacement is a simple-yet-powerful mechanism that opens up the possibility for complex structural components in artificial molecular machines to undergo information-based reconfiguration in response to their environments.

Three Gram-stain positive, aerobic actinomycete strains, designated NEAU-A15T, NEAU-A13 and NEAU-C4, were isolated from rhizosphere soil of wheat (Triticum aestivum L.) collected from Langfang, Hebei Province, China. Based on their morphological characteristics, biochemical features and molecular phylogenetic studies, these strains were concluded to belong to a new member of the genus Glycomyces. 16S rRNA gene sequence analysis showed that strain NEAU-A15T shares 99.91% and 99.80% 16S rRNA gene sequence similarity with NEAU-A13 and NEAU-C4, respectively, and these three strains showed high sequence similarities to Glycomyces algeriensis DSM 44727T (99.24, 99.45, 99.38%), Glycomyces lechevalierae DSM 44724T (98.97, 99.17, 99.11%) and Glycomyces rutgersensis DSM 43812T (98.83, 99.04, 98.97%). Phylogenetic analysis indicated that these three strains clustered together and formed a cluster with Glycomyces tritici NEAU-C2T (97.30, 97.73, 99.48%), G. algeriensis DSM 44727T, G. lechevalierae DSM 44724T and G. rutgersensis DSM 43812T. These three strains were observed to contain MK-10(H2), MK-10(H6) and MK-11 as menaquinones. The whole cell sugar profiles were found to contain galactose, ribose and xylose. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, phosphoglycolipid, phosphatidylinositol mannoside and an unidentified glycolipid. The major fatty acids were identified as anteiso-C15:0, iso-C16:0, anteiso-C17:0 and iso-C15:0. The DNA–DNA hybridization values between strain NEAU-A15T and NEAU-A13/NEAU-C4 were 86.2 ± 2.3% and 83.4 ± 3.5%, respectively. The values between these three strains and their close phylogenetic relatives were 48–52%, supporting the conclusion that they belong to a distinct genomic species. An array of phenotypic characteristics also differentiated these isolates from their closely related species. On the basis of the genetic and phenotypic properties, strains NEAU-A15T, NEAU-A13 and NEAU-C4 can be classified as representatives of a novel species of the genus Glycomyces, for which the name Glycomyces luteolus sp. nov., is proposed. The type strain is NEAU-A15T (= DSM 104643T = CGMCC 4.7394T).

Compared to conventional imaging spectrometry, coded aperture snapshot spectral imaging (CASSI) has the advantages of high throughput snapshot imaging etc. But because of the presence of the dispersive element, CASSI system suffers the effect of the same optical aberrations as traditional single slit spectrometer. To study the effect of keystone on signal acquisition, the model of spatial–spectral aliasing and the reconstructed result in CASSI system, combined with the principle of coded aperture spectral imaging and the reconstruction algorithm, the relative peak signal-to-noise ratio (PSNR) of the reconstructed image and the maximal error of the reconstructed spectral curve at different spectral band bending were calculated and analyzed. The experimental result showed that spectral band offset of the signal acquired by the detector will change the degree of spatial–spectral aliasing. Compared to the reconstructed results with no spectral band bending, distinct errors are exhibited when spectral band bending emerges. And the reconstructed spectral curve tends to be smooth on both sides of the spectral channel. In order to reconstruct the spectral cube with high accuracy, spectral band offset should be no more than half a pixel.

Fourier transform infrared spectroscopy is an important technique in studying molecular energy levels, analyzing material compositions, and environmental pollutants detection. A novel rotational motion Fourier transform infrared spectrometer with high stability and ultra-rapid scanning characteristics is proposed in this paper. The basic principle, the optical path difference (OPD) calculations, and some tolerance analysis are elaborated. The OPD of this spectrometer is obtained by the continuously rotational motion of a pair of parallel mirrors instead of the translational motion in traditional Michelson interferometer. Because of the rotational motion, it avoids the tilt problems occurred in the translational motion Michelson interferometer. There is a cosine function relationship between the OPD and the rotating angle of the parallel mirrors. An optical model is setup in non-sequential mode of the ZEMAX software, and the interferogram of a monochromatic light is simulated using ray tracing method. The simulated interferogram is consistent with the theoretically calculated interferogram. As the rotating mirrors are the only moving elements in this spectrometer, the parallelism of the rotating mirrors and the vibration during the scan are analyzed. The vibration of the parallel mirrors is the main error during the rotation. This high stability and ultra-rapid scanning Fourier transform infrared spectrometer is a suitable candidate for airborne and space-borne remote sensing spectrometer.

INTRODUCTION Since the 1980s, the design and synthesis of molecular machines has been identified as a grand challenge for molecular engineering. Robots are an important type of molecular machine that automatically carry out complex nanomechanical tasks. DNA molecules are excellent materials for building molecular robots, because their geometric, thermodynamic, and kinetic properties are well understood and highly programmable. So far, the development of DNA robots has been limited to simple functions. Most DNA robots were designed to perform a single function: walking in a controlled direction. A few demonstrations included a second function combined with walking (for example, picking up nanoparticles or choosing a path at a junction). However, these relatively more complex functions were also more difficult to control, and the complexity of the tasks was limited to what the robot can perform within 3 to 12 steps. In addition, each robot design was tailored for a specific task, complicating efforts to develop new robots that perform new tasks by combining functions and mechanisms. RATIONALE The design and synthesis of molecular robots presents two critical challenges, those of modularity and algorithm simplicity, which have been transformative in other areas of molecular engineering. For example, simple and modular building blocks have been used for scaling up molecular information processing with DNA circuits. As in DNA circuits, simple building blocks for DNA robots could enable more complex nanomechanical tasks, whereas modularity could allow diverse new functions performed by robots using the same set of building blocks. RESULTS We demonstrate a DNA robot that performs a nanomechanical task substantially more sophisticated than previous work. We developed a simple algorithm and three modular building blocks for a DNA robot that performs autonomous cargo sorting. The robot explores a two-dimensional testing ground on the surface of DNA origami, picks up multiple cargos of two types that are initially at unordered locations, and delivers each type to a specified destination until all cargo molecules are sorted into two distinct piles. The robot is designed to perform a random walk without any energy supply. Exploiting this feature, a single robot can repeatedly sort multiple cargos. Localization on DNA origami allows for distinct cargo-sorting tasks to take place simultaneously in one test tube or for multiple robots to collectively perform the same task. On average, our robot performed approximately 300 steps while sorting the cargos. The number of steps is one to two magnitudes larger than the previously demonstrated DNA robots performing additional tasks while walking. Using exactly the same robot design, the system could be generalized to multiple types of cargos with arbitrary initial distributions, and to many instances of distinct tasks in parallel, whereas each task can be assigned a distinct number of robots depending on the difficulty of the task. CONCLUSION Using aptamers, antibodies, or direct conjugation, small chemicals, metal nanoparticles, and proteins could be transported as cargo molecules so that the cargo-sorting DNA robots could have potential applications in autonomous chemical synthesis, in manufacturing responsive molecular devices, and in programmable therapeutics. The building blocks developed in this work could also be used for diverse functions other than cargo sorting. For example, inspired by ant foraging, adding a new building block for leaving pheromone-like signals on a path, DNA robots could be programmed to find the shortest path and efficiently transport cargo molecules. With simple communication between the robots, they could perform even more sophisticated tasks. With more effort in developing modular and collective molecular robots, and with simple and systematic approaches, molecular robots could eventually be easily programmed like macroscopic robots, but working in microscopic environments.

Near earth space is a space which has important strategic significance and application value in military, scientific exploration and other industry fields, one of the most practical application is to make a reconnaissance platform that can work normally in the near earth space. In this paper, a two-dimensional photoelectric turntable for video surveillance in near-earth space is designed, which can observe the azimuth angle 360° and pitch angle from −110° to 10°, and the capacity of this photoelectric turntable is 7 kg in a space of ϕ300 mm. The optical imaging load in the photoelectric turntable can output high-definition video in real time and the original image is stored in the memory card simultaneous. What is more, the imaging effect can be adjusted by controlling the magnification and focal length by sending commands through serial communication ports. The two-dimensional photoelectric turntable designed in this paper is mounted on the payload cabin and raised to 32.5 km for surveillance imaging. The experimental results show that the two-dimensional photoelectric turntable can work normally in the harsh near space environment, and the optical imaging load can output and record fluent high-definition video. The photoelectric turntable designed in this paper will be equipped with other optical load and take part in some near space exploration tasks in the future and obtain corresponding result.

DNA origami and other DNA nanostructures have been used as scaffolds to organize various molecules with high programmability and spatial precision, but of a limited size. Arrays of DNA origami and smaller DNA tiles have been created to provide structural patterns on a larger scale, but either with limited pattern complexity, or requiring specific tile-tile interactions that limit practical experimental demonstrations. Here we show that the principle of non-deterministic Truchet tiling can be applied to provide a simple solution for creating complex nanoscale patterns that have combinatorial diversity and programmable features. As an example, we constructed patterns of random mazes with distinct emergent properties and with sizes of up to several microns, each self-assembled from thousands of square DNA origami tiles that are labeled with simple local patterns. We further demonstrated precise control of pattern complexity by creating DNA origami arrays with unprecedented yield and finite sizes ranging from 4 to 25 tiles in each assembly, and showed the generality of our approach using arrays of triangular DNA origami tiles. The nanoscale mazes that we created could be used to test the robustness of molecular machines against a variety of operating environments with increasing complexity. Broadly speaking, by attaching proteins, metal nanoparticles, and organic dyes to origami arrays with combinatorial patterns of programmable features, our approach could potentially enable efficient screening of functional molecular devices and advance nanoscale fabrication. Importantly, our work highlights the need for better understanding of programmable disorder and how it can be more generally applied in engineered molecular systems to enable solutions for problems that simultaneously demand complexity, diversity, and efficiency -- much like the algorithms we see in nature that exploit a sophisticated blend of deterministic and random processes.

A solution-phase DNA chip is produced using DNA origami-based asymmetric self-assembled tiles incorporating single-stranded DNA linear probes. This DNA origami chip is fully spatially addressable, without having to use position index oligonucleotides. The DNA hybridization is readily detected via atomic force microscopy.

This paper presents a DNA algorithm which adds two nonnegative binary integers using self-assembly in constant steps. The approach has the benefit of greater experimental simplicity when compared with previous DNA addition algorithms. For the addition of two binary n-bit integers, O(n) is different from DNA strands and only O(1) biochemical experimental procedures are required.

Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophin in the central nervous system (CNS), and performs many biological functions such as neural survival, differentiation, and plasticity. Previous studies have suggested that variants in the BDNF gene increase the risk of schizophrenia. In this study, we genotyped one (GT)n dinucleotide repeat and three SNPs (rs6265, rs2030324, and rs2883187) in a Chinese sample (617 cases and 672 controls). In addition, we performed an updated meta-analysis based on 16 population-based case-control studies examining association between rs6265 and schizophrenia. In single-locus analysis, no significant association was found between BDNF polymorphisms and schizophrenia in our subjects. The meta-analysis based on Asian and Caucasian subjects did not give positive result that rs6265 is associated with schizophrenia. However, haplotype analysis found a common four-locus haplotype is protective against schizophrenia (Case 3.1% vs Control 7%, p = 0.0011). Our data provides evidence that BDNF is a susceptibility gene for schizophrenia in Chinese subjects.

Smart-phone is a major channel of interpersonal communication. As the rapid development of communication technology, its function is becoming ever more powerful. Meanwhile, people are far more dependent on it. This study aims at investigating how long undergraduate students spend on their smart-phones everyday and the relationship between the time of smart-phone use and loneliness, as while as examining the role of interpersonal personality characteristics in moderating this relationship. The design of the study involved an experience sampling methodology (ESM), 97 undergraduates completed loneliness survey and reported time of smart-phone use every day for a whole week, resulting in a total of 679 observations. And the Inventory of Interpersonal Problems (IIP-32) was used to attain their needs and motivations on interpersonal communication. Results showed that: a) college students spend 5.26±3.40 hours on the smart-phone including 2.37 hours for social communication, b) there is no significant correlation between the time of smart-phone use and loneliness, c) Social-Avoidant (FG) of IIP was negatively associated with smart-phone use, and Exploitable (JK) was positively associated with this time, especially on social communication, d) Cold (DE) impacts the degree of association between loneliness and smart-phone social communication, mainly in the aspect of online social communication.

The pathogenesis of Mycoplasma pneumoniae infection involves cytoadherence of M. pneumoniae to the ciliated respiratory epithelium (CRE), followed by CRE injury caused by the M. pneumoniae. However, whether CRE abnormalities are related to the severity of M. pneumoniae pneumonia (MP) remains to be determined.Thirty-eight patients with MP and 8 controls who underwent fiber-optic bronchoscopy with bronchial biopsy were included in this study. Patients with MP were divided into 2 groups: a mild disease group (12 patients) and a severe disease group (26 patients). The clinical features, laboratory findings, chest radiographic findings, and CRE abnormalities were characterized.Patients with severe pneumonia had a higher epithelial integrity score than those with mild pneumonia (5.1 ± 0.76 vs 3.8 ± 0.75; p0.01). Patients with severe CRE abnormalities had a longer duration of fever (p0.01), higher C-reactive protein (p0.01), and lower proportion of blood lymphocytes (p0.05) compared to those with mild abnormalities. Patients with a positive bacteria culture had a higher epithelial integrity score compared to those with a negative culture (6.0 ± 0.44 vs 4.8 ± 0.71; p0.01).CRE abnormalities are closely related to the severity of MP. These findings extend our current knowledge of MP.

In the field of Fourier-transform spectroscopy, tilt and shearing problems caused by the moving components in a translational type of spectrometer reduce the quality of the interferogram dramatically. While, the spectrometer based on rotational motion can avoid these problems. In this paper, a novel rotational type of interferometer, called rotating parallel-mirror-pair interferometer (RPMPI), is presented. Its principle and properties are studied. This interferometer consists of one beam splitter, two fixed flat mirrors, and one rotating wedged parallel-mirror-pair (PMP). The optical path difference (OPD) is obtained by the rotational motion of the PMP. Factors that affect the maximum OPD include the wedged angle of the rotating PMP, the distance between the two parallel mirrors, the direction of the incident ray, and the range of rotating angle. This interferometer can operate either in swinging mode or continuous rotary mode depending on the range of the rotating angle. In swinging mode, the OPD function is linear. In continuous rotary mode, the sampling efficiency is higher and it can operate as an ultra rapid scanning interferometer.

DNA origami (Rothemund, 2006) and smaller DNA tiles (Winfree et al., 1998) have been used as effective scaffolds to create complex patterns for organizing molecules with nanometer precision but of a limited size. Arrays of DNA origami (Liu et al., 2011) and DNA tiles have been shown to be capable of creating patterns in a larger scale, either periodically or following a specific set of rules defined by a cellular automaton (Rothemund et al., 2004). Here we aim to create a variety of large-scale complex patterns by using a combinatorial approach with a mathematically simple and elegant rule called Truchet tiling.

We propose a theoretical framework that uses a novel DNA strand displacement mechanism to implement abstract chemical reaction networks (CRNs) on the surface of a DNA nanostructure, and show that surface CRNs can perform efficient algorithmic computation and create complex spatial dynamics. We argue that programming molecular behaviors with surface CRNs is systematic, parallel and scalable.

To construct sophisticated biochemical circuits from scratch, one needs to understand how simple the building blocks can be and how robustly such circuits can scale up. Using a simple DNA reaction mechanism based on a reversible strand displacement process, we experimentally demonstrated several digital logic circuits, culminating in a four-bit square-root circuit that comprises 130 DNA strands. These multilayer circuits include thresholding and catalysis within every logical operation to perform digital signal restoration, which enables fast and reliable function in large circuits with roughly constant switching time and linear signal propagation delays. The design naturally incorporates other crucial elements for large-scale circuitry, such as general debugging tools, parallel circuit preparation, and an abstraction hierarchy supported by an automated circuit compiler.

This paper presents an approach to enhance the resolution of refocused images by super resolution methods. In plenoptic imaging, we demonstrate that the raw sensor image can be divided to a number of low-resolution angular images with sub-pixel shifts between each other. The sub-pixel shift, which defines the super-resolving ability, is mathematically derived by considering the plenoptic camera as equivalent camera arrays. We implement simulation to demonstrate the imaging process of a plenoptic camera. A high-resolution image is then reconstructed using maximum a posteriori (MAP) super resolution algorithms. Without other degradation effects in simulation, the super resolved image achieves a resolution as high as predicted by the proposed model. We also build an experimental setup to acquire light fields. With traditional refocusing methods, the image is rendered at a rather low resolution. In contrast, we implement the super-resolved refocusing methods and recover an image with more spatial details. To evaluate the performance of the proposed method, we finally compare the reconstructed images using image quality metrics like peak signal to noise ratio (PSNR).

Bennett's proposed chemical Turing machine is one of the most important thought experiments in the study of the thermodynamics of computation. Yet the sophistication of molecular engineering required to physically construct Bennett's hypothetical polymer substrate and enzymes has deterred experimental implementations. Here we propose a chemical implementation of stack machines -- a Turing-universal model of computation similar to Turing machines -- using DNA strand displacement cascades as the underlying chemical primitive. More specifically, the mechanism described herein is the addition and removal of monomers from the end of a DNA polymer, controlled by strand displacement logic. We capture the motivating feature of Bennett's scheme: that physical reversibility corresponds to logically reversible computation, and arbitrarily little energy per computation step is required. Further, as a method of embedding logic control into chemical and biological systems, polymer-based chemical computation is significantly more efficient than geometry-free chemical reaction networks.

The impressive capabilities of the mammalian brain--ranging from perception, pattern recognition and memory formation to decision making and motor activity control--have inspired their re-creation in a wide range of artificial intelligence systems for applications such as face recognition, anomaly detection, medical diagnosis and robotic vehicle control. Yet before neuron-based brains evolved, complex biomolecular circuits provided individual cells with the 'intelligent' behaviour required for survival. However, the study of how molecules can 'think' has not produced an equal variety of computational models and applications of artificial chemical systems. Although biomolecular systems have been hypothesized to carry out neural-network-like computations in vivo and the synthesis of artificial chemical analogues has been proposed theoretically, experimental work has so far fallen short of fully implementing even a single neuron. Here, building on the richness of DNA computing and strand displacement circuitry, we show how molecular systems can exhibit autonomous brain-like behaviours. Using a simple DNA gate architecture that allows experimental scale-up of multilayer digital circuits, we systematically transform arbitrary linear threshold circuits (an artificial neural network model) into DNA strand displacement cascades that function as small neural networks. Our approach even allows us to implement a Hopfield associative memory with four fully connected artificial neurons that, after training in silico, remembers four single-stranded DNA patterns and recalls the most similar one when presented with an incomplete pattern. Our results suggest that DNA strand displacement cascades could be used to endow autonomous chemical systems with the capability of recognizing patterns of molecular events, making decisions and responding to the environment.

The prospects of programming molecular systems to perform complex autonomous tasks has motivated research into the design of synthetic biochemical circuits. Of particular interest to us are cell-free nucleic acid systems that exploit non-covalent hybridization and strand displacement reactions to create cascades that implement digital and analog circuits. To date, circuits involving at most tens of gates have been demonstrated experimentally. Here, we propose a DNA catalytic gate architecture that appears suitable for practical synthesis of large-scale circuits involving possibly thousands of gates.