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The article titled "Retraction Note: LncRNA LINC00152 promoted glioblastoma progression through targeting the miR-107 expression" has been retracted by the Editor-in-Chief of Environmental Science & Pollution Research. The retraction was due to concerns raised about Figure 3A, which appeared to be identical to a panel from a previously published article by different authors. As a result, the Editor-in-Chief no longer has confidence in the results and conclusions of the retracted article. The publisher has been unable to contact the authors. [Extracted from the article]

Biological systems mainly utilize chemical energy to fuel autonomous molecular motors, enabling the system to be driven out of equilibrium1. Taking inspiration from rotary motors such as the bacterial flagellar motor2 and adenosine triphosphate synthase3, and building on the success of light-powered unidirectional rotary molecular motors4–6, scientists have pursued the design of synthetic molecular motors solely driven by chemical energy7–13. However, designing artificial rotary molecular motors operating autonomously using a chemical fuel and simultaneously featuring the intrinsic structural design elements to allow full 360° unidirectional rotary motion like adenosine triphosphate synthase remains challenging. Here we show that a homochiral biaryl Motor-3, with three distinct stereochemical elements, is a rotary motor that undergoes repetitive and unidirectional 360° rotation of the two aryl groups around a single-bond axle driven by a chemical fuel. It undergoes sequential ester cyclization, helix inversion and ring opening, and up to 99% unidirectionality is realized over the autonomous rotary cycle. The molecular rotary motor can be operated in two modes: synchronized motion with pulses of a chemical fuel and acid–base oscillations; and autonomous motion in the presence of a chemical fuel under slightly basic aqueous conditions. This rotary motor design with intrinsic control over the direction of rotation, simple chemical fuelling for autonomous motion and near-perfect unidirectionality illustrates the potential for future generations of multicomponent machines to perform mechanical functions.A homochiral rotary molecular motor shows autonomous unidirectional rotation around a single bond driven by a chemical fuel. [ABSTRACT FROM AUTHOR]

The debate on technological innovation shocks and its effect on the environment are of great interest to academicians and environmentalists worldwide. At present, primary focus of this research is to investigate the asymmetric technology shocks and its impact on CO2 emissions for BRICS economies. The linear and non-linear panel ARDL models are applied to compute both short-run and long-run dynamics of technology shocks and CO2 emissions. Asymmetric estimates confer that a positive shock in patents reduces the CO2 emissions by 0.418%, whereas negative shock increases the CO2 emissions by 0.854%. Contrariwise, the trademark positive shock increases the carbon emissions by 0.416% and vice versa. The non-linear analysis provides an opportunity to measure the direction and magnitude of positive and negative shocks in technology on the environmental quality of BRICS economies. Hence, policymakers and environmentalists should devise their strategies by keeping in mind the impacts of positive and negative shocks. [ABSTRACT FROM AUTHOR]

This paper uses a novel numerical approach to approximate the coupled Cahn–Hilliard equations, which are a highly nonlinear system depicting the phase separation of the homopolymer and copolymer mixtures. The new method is named 3S-IEQ, and its construction and calculation are more straightforward than the invariant energy quadratization and scalar auxiliary variable methods. Notably, we only need to solve two linear decoupled constant-coefficient equations at each time step. Numerical simulations are shown [ABSTRACT FROM AUTHOR]

Fog computing has been recently proposed to move certain cloud computing services down to edge networks especially for mobile applications, aiming at improving the throughput and delay through the collaboration of mobile devices at edge wireless networks. Yet, the current edge wireless networks are the bottleneck that prohibits mobile devices to efficiently share their resources, due to the lack of an efficient mechanism of coordinating heterogeneous wireless networks (e.g., LTE, WiFi, and WiMax) to better utilize the radio resources. In this paper, we propose MiFo, a novel hierarchical dual-layer edge network integration framework for fog computing. At the lower level, the Mist layer manages the baseband resources of homogeneous networks in a centralized way, which can enhance the transmission performance through physical layer cooperation among base stations. At the upper level, the Fog layer coordinates the heterogeneous network access and the resource scheduling. In MiFo, we also propose a multi-stream concurrent (MSC) transmission protocol, which can make full use of diverse wireless network resources and significantly improve the data transmission rate of multi-mode mobile devices. The proposed MSC transmission protocol can also achieve smart handover and improve the energy efficiency as well. [ABSTRACT FROM AUTHOR]

Expression of recombinant proteins in Escherichia coli often requires use of inducible promoters to shorten the lag phase and improve protein productivity and final protein titer. Synthetic molecules that cannot be metabolized by E. coli, such as isopropyl thiogalactopyranoside (IPTG), have been frequently used to trigger the protein expression during early exponential growth phase. This practice has many drawbacks, including high cost and toxicity of IPTG, complex operating procedure, and non-uniform protein expression pattern (some cells in the population do not express recombinant proteins). A few auto-inducible protein expression systems have been developed recently to overcome some of these limitations, but they required use of an additional plasmid or presence of large (a few kilobases) DNA part to be functional, making plasmid construction to be difficult, especially when multiple genes need to be expressed. In this study, by using RNA sequencing, we identified a short, endogenous promoter (PthrC) that can be auto-induced during early exponential growth phase, and improved its performance by use of native and mutated regulatory elements. We found that the developed mutants of PthrC drove uniform protein expression—close to 100% of cells were fluorescent when green fluorescence protein was used as target protein—and cells carrying them could achieve much higher cell density than those with T7 promoter (PT7), a commonly used inducible promoter. In terms of promoter strength (product protein quantity per cell), the developed promoter mutants can cover a range of strength, from 30 to 150% of maximal strength of PT7. One strong mutant (PthrC3_8) was found to work well at a large range of temperature (22, 30, 37 °C) and in various media, and was also confirmed to cause less stress to host cell than PT7 when they were used to express a toxic protein. We foresee that PthrC3 and its mutants will be useful genetic parts for various applications including metabolic engineering and biocatalysis. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) LINC00152 plays important roles in the progression of some tumors. However, the role of LINC00152 in human l glioblastoma is still unknown. In this study, we indicated that LINC00152 expression level was upregulated in glioblastoma tissues and cell lines. Overexpression of LINC00152 promoted the U87 and LN229 cell proliferation and invasion. Moreover, overexpression of LINC00152 suppressed the E-cadherin expression, where ectopic expression of LINC00152 promoted the N-cadherin, Vimentin, and Snail expression. These results suggested that LINC00152 enhanced epithelial-to-mesenchymal transition (EMT) program in the glioblastoma cell. Overexpression of LINC00152 suppressed the miR-107 expression in the U87 cell and enhanced the HMGA2 expression, which is a direct target gene of miR-107. In addition, we showed that the miR-107 expression was downregulated in the glioblastoma tissues and cell lines. Interesting, the expression of LINC00152 was negatively related with miR-107 expression in the glioblastoma tissues. Furthermore, LINC00152 promoted the glioblastoma cell proliferation and invasion through inhibiting miR-107 expression. These data suggested that LINC00152 acted as oncogene roles in the glioblastoma cell partly through targeting the miR-107 expression. [ABSTRACT FROM AUTHOR]

A new method for characterizing architectural elements of fractured-cavernous carbonate reservoirs was proposed, with application to an Ordovician reservoir in the Tahe Oilfield, Tarim basin. The new method integrates observations from outcrop analogs and concepts from modern karst theory for the mapping and modeling of fractured-cavernous reservoirs. In this paper, fractured-cavernous reservoirs were divided into 4 architectural element types—underground river caverns, sinkholes, discrete internal caverns, and faults. Architectural elements of the Ordovician reservoir in Tahe oilfield were identified and characterized by integrating well logs and seismic data. A new method constrained by faults, karst zones, and seismic acoustic impedance data, was introduced to build a 3D model of architectural elements of fractured-cavernous reservoir in the S48 unit of Tahe Oilfield. A porosity model was then derived from the architectural element model using facies-constrained method. The research provides a work-flow for the characterization of fracturedcavernous reservoirs and determining optimal methods for maximizing oil recovery in the study area or in similar areas. [ABSTRACT FROM AUTHOR]

In this paper, we propose an energy-efficient compressed data aggregation framework for three-dimensional underwater acoustic sensor networks (UASNs). The proposed framework consists of two layers, where the goal is to minimize the total energy consumption of transmitting the data sensed by nodes. The lower layer is the compressed sampling layer, where nodes are divided into clusters. Nodes are randomly selected to conduct sampling, and then send the data to the cluster heads through random access channels. The upper layer is the data aggregation layer, where full sampling is adopted. We also develop methods to determine the number of clusters and the probability that a node participates in data sampling. Simulation results show that the proposed framework can effectively reduce the amount of sampling nodes, so as to reduce the total energy consumption of the UASNs. [ABSTRACT FROM AUTHOR]

Fracture-cavity reservoirs can be described in terms of storage space, filling materials and distribution, however, characterizing these variables remains a challenge. In this study, a method was developed to characterize complex reservoirs by integrating outcrop, core, well log, and seismic data from the Tahe oilfield. Outcrop analogs were used to identify and qualitatively analyze the genesis of different reservoir spaces. Cores, well logs, and seismic data were used to identify different types of reservoir space in the subsurface, to describe the spatial distribution, and to establish the distribution pattern of fracture-cavity reservoirs. Clastic sediments, collapse breccia, and chemical fillings were described from the cores and used to assess porosity and permeability. On the basis of the results, a three-dimensional geological model was constructed incorporating a structural model, a reservoir space model, and a property model. Caves and fractures were the main storage spaces and seepage passages. The cave model was built using multi-point geostatistical simulation, while the fracture model was established using deterministic modeling combined with manual interpretations and ant-tracking technology. [ABSTRACT FROM AUTHOR]

Video streaming has become one of the most popular networked applications and, with the increased bandwidth and computation power of mobile devices, anywhere and anytime streaming has become a reality. Unfortunately, it remains a challenging task to compress high-quality video in real-time in such devices given the excessive computation and energy demands of compression. On the other hand, transmitting the raw video is simply unaffordable from both energy and bandwidth perspective. In this paper, we propose DualEMC, a novel cloud-assisted video compression mechanism for mobile devices. DualEMC leverages the abundant cloud server resources for motion estimation (ME), which is known to be the most computation-intensive step in video compression, accounting for over 90 % of the computation time. With DualEMC, a mobile device selects and uploads only the key information of each picture frame to cloud servers for mesh-based ME, eliminating most of the local computation operations. We develop smart algorithms to identify the key mesh nodes, resulting in minimum distortion and data volume for uploading. Our simulation results demonstrate that DualEMC saves almost 30 % energy for video compression and transmission. [ABSTRACT FROM AUTHOR]

Ab initio calculations of the magnetic and electric hyperfine fields and the magnetic moments were performed for the Fe doped SnO dilute magnetic semiconductors with the Wien2k code embodying the full-potential linearized augmented plane-wave method. The calculated results for the neutral system and the different charged state systems with and without the oxygen vacancy show clearly that the ground state is all magnetic and that the addition of electrons and the appearance of oxygen vacancy can increase the magnetic moment and the magnetic hyperfine field and reduce the electric hyperfine field. The energy level splitting of the Fe- 3d orbit can lead to enhancing the magnetic moment and, therefore, a very large magnetic moment of 5 μ is obtained for the SnFeO charged system. [ABSTRACT FROM AUTHOR]

The g-factors of the rotational states of the positive parity yrast band from spin I=10 to spin I=16 in even-even nucleus Cd have been measured by the transient-magnetic-field ion implantation perturbed angular distribution method. The high spin states of Cd were populated by the fusion evaporation reaction Ge (Cl, 1p4n) Cd. The measured g-factors increase gradually as the spin increases from 10 to 16 due to the g neutron alignment. The g neutrons are fully aligned at spin I=16. This state is the band head state of the anti-magnetic rotational band in Cd. The measured g-factor of this state is -0.09. The present results support that this band head state may have the configuration $\pi (g_{9/2})^{-2}_{J=0}\otimes \nu (h_{11/2})^{2}_{J=10}\nu (g_{7/2})^{2}_{J=6}$. [ABSTRACT FROM AUTHOR]

YouTube-like video sharing sites (VSSes) have gained increasing popularity in recent years. Meanwhile, Face-book-like online social networks (OSNs) have seen their tremendous success in connecting people of common interests. These two new generation of networked services are now bridged in that many users of OSNs share video contents originating from VSSes with their friends, and it has been shown that a significant portion of views of VSS videos are attributed to this sharing scheme of social networks. To understand how the video sharing behavior, which is largely based on social relationship, impacts users' viewing pattern, we have conducted a long-term measurement with RenRen and YouKu, the largest online social network and the largest video sharing site in China, respectively. We show that social friends have higher common interest and their sharing behaviors provide guidance to enhance recommended video lists. In this paper, we take a first step toward learning OSN video sharing patterns for video recommendation. An autoencoder model is developed to learn the social similarity of different videos in terms of their sharing in OSNs. We, therefore, propose a similarity-based strategy to enhance video recommendation for YouTube-like social media. Evaluation results demonstrate that this strategy can remarkably improve the precision and recall of recommendations, as compared to other widely adopted strategies without social information. [ABSTRACT FROM AUTHOR]

d-Amino acid oxidase is an important biocatalyst used in a variety of fields, and its economically justified level recombinant expression in Escherichia coli has not been established. To accomplish this, after a single Phe54Tyr substitution, fusion proteins of d-amino acid oxidase from Trigonopsis variabilis (TvDAO) with 6 × His-tags were constructed and expressed in E. coli. The effects of his-tags fusing position were revealed. Significant increase in holoenzyme percent and protein solubility made N-terminus tagged TvDAO (termed NHDAO) a suitable choice for TvDAO production. However, reduced cell growth and protein production rates were also observed for the NHDAO bearing strains. To optimize the performance of NHDAO production, changes of culture medium were tested. Finally, a production of 140 U/mL or 3.48 g active enzyme per liter which accounted for 41.4 % of the total protein, and a specific activity of 16.68 U/mg for the crude extract, were achieved in a 3.7 L fermenter in 28.5 h. This indicated a possibility for functional and economical TvDAO expression in E. coli to meet the industrial need. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs), often composed of a large number of sensor nodes with limited power, have been widely used for environmental monitoring and battlefield surveillance. A basic operation in such networks is data gathering. In the applications of data gathering without aggregation, the 1-hop nodes always incur much heavier traffic load compared with other nodes, which determine the lifetime of the whole network. Due to the energy constrained nature of sensor devices, energy-efficient methods should be employed for data gathering. In this paper, we propose a Load-Balanced and energy-efficient Tree (LBT) algorithm to maximize the lifetime of WSNs, which takes into account the load balance and energy efficiency of 1-hop nodes. To the best of our knowledge, we are the first to present the upper bound of network lifetime for data gathering without aggregation with tree-based topology. Simulation results demonstrate that our algorithm utilizes up to 98 % of the total energy of the 1-hop nodes and outperforms the state-of-the-art algorithms in terms of network lifetime. Furthermore, LBT can achieve a lifetime consistently close to the upper bound. [ABSTRACT FROM AUTHOR]

Recent decades have witnessed the fast development of high-speed railway systems in many countries, which have significantly shortened the travel time between distant cities. Accompanied with this convenience is the challenge for cell phone vendors to provide broadband Internet access for passengers, particularly considering the fast changing channel conditions in high-speed trains and the limited battery of cell phones, which often cannot be re-charged in trains. In this paper, inspired by the unique spatial-temporal characteristics of wireless signals along high-speed railways, we propose a novel energy-efficient scheduling approach for uploading data from cell phones, both with soft deadlines (e.g., documents) and hard deadlines (e.g., video streaming). Our solution effectively predicts the signal strength through its spatial-temporal periodicity in this new application scenario, and smartly adjusts the transmission rate to maximize the overall data transmission rate and yet conserves the energy consumption. Performance evaluation based on realistic railway scenarios and H.264 video traces demonstrate the effectiveness of our solution and its superiority as compared to the existing solutions. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Here we report GT (Guanin/Thymine) standard (GTS) for plasmid construction under which DNA sequences are defined as two types of standard, reusable parts (fragment and barcode). We develop a technology that can efficiently add any two barcodes to two ends of any fragment without leaving scars in most cases. We can assemble up to seven such barcoded fragments into one plasmid by using one of the existing DNA assembly methods, including CLIVA, Gibson assembly, In-fusion cloning, and restriction enzyme-based methods. Plasmids constructed under GTS can be easily edited, and/or be further assembled into more complex plasmids by using standard DNA oligonucleotides (oligos). Based on 436 plasmids we constructed under GTS, the averaged accuracy of the workflow was 85.9%. GTS can also construct a library of plasmids from a set of fragments and barcodes combinatorically, which has been demonstrated to be useful for optimizing metabolic pathways. Construction of plasmids from multiple fragments often uses customised parts and leaves scars where fragments are joined. Here the authors develop a method for barcoding fragments and constructing plasmids in a scarless manner from a collection of standard parts. [ABSTRACT FROM AUTHOR]