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The threat of cyber-attacks is on the rise in the digital world today. As such, effective cybersecurity solutions are becoming increasingly important for detecting and combating cyber-attacks. The use of machine learning techniques for network intrusion detection is a growing area of research, as these techniques can potentially provide a means for automating the detection of attacks and abnormal traffic patterns in real-time. However, misclassification is a common problem in machine learning for intrusion detection, and the improvement of machine learning models is hindered by a lack of insight into the reasons behind such misclassification. This paper presents an interactive method of visualizing network intrusion detection data in three-dimensions. The objective is to facilitate the understanding of network intrusion detection data using a visual representation to reflect the geometric relationship between various categories of network traffic. This interactive visual representation can potentially provide useful insight to aid the understanding of machine learning results. To demonstrate the usefulness of the proposed visualization approach, this paper presents results of experiments on commonly used network intrusion detection datasets.

To improve profitability and reduce demand uncertainty, lateral transshipment is employed in this study to reallocate inventory with updated demand information. A decentralized inventory system with two retailers ordering from one common supplier is analyzed. Each retailer places the order independently before the selling season begins based on original demand forecast. As lead time elapses, more information is collected to update the demand forecast and transshipment is examined. This study constructs a two-stage model and applies backward induction to solve the problem. A threshold transshipment policy is proposed at stage 2. The existence of unique Nash equilibrium is proven at stage 1. Both the centralized system with transshipment and the newsvendor-like system without transshipment are studied as benchmarks to evaluate the performance of transshipment in the decentralized system. Extensive numerical examples are conducted to provide some valuable management implications. The results show that transshipment can lead to profit increase, especially in the system with high informative value of demand forecast updates.

Poor Data Quality (DQ) is amajor culprit in the failure of ERP implantation. Previous DQ solutions focus more on technical approaches, ignoring the importance of seeking the root causes. Th...

Computational fluid dynamics (CFD) model of coal combustion is coupled with the one-dimensional hydrodynamic model of supercritical steam, and applied in the simulation of the superheater. The convective heat exchangers are neglected. Complex tube arrangements can be modeled with the aid of AutoCAD, and therefore the simulation could offer detailed information on heat exchangers. It is found that the outlet steam temperature of the tube is very sensitive to the variation of ash deposit temperature. Therefore it is not reasonable to use decoupled method for predicting the energy flux transported to the steam. The outlet steam temperature of a row of tubes is compared with the running data from the power plant. The simulation result fits well with running data. Nevertheless, one can impose an average steam temperature plus 50 K as the tube outside surface temperature; then calculates the temperature of the ash deposit according to the thermal resistance of ash deposit and energy flux. The result from this “simplified” coupled method is very close to fully coupled method.

Purpose The design and retrofit of the heat exchangers in a boiler should take into account the processes occurring on the side of combustion and steam. For this reason, this study aims to couple a one-dimensional hydrodynamic model of steam with computational fluid dynamics (CFD) simulation of flue gas. Design/methodology/approach Radiant/semi-radiant platen heat exchangers are simplified as plane surfaces for CFD, while convective heat exchangers are introduced into the CFD simulation as energy/momentum absorption sources. Findings Numerical simulation is performed for a 1,000 MWe coal-fired ultra-supercritical boiler. The calculation results are validated by the thermodynamic design data. Tube outside surface temperature, as well as ash deposit temperature distributions, are obtained. Originality/value Complex tube arrangements can be completed with the aid of AutoCAD, and therefore, the simulation could offer detailed information of heat exchangers. In a word, a more reliable modeling of the whole steam generation process is achieved.

Unraveling the role of transition-metal doping in affecting the native spinel-structured nanosheets' water splitting remains a grand challenge. In this work, a series of spinel-structured nanosheets wrapped hollow nitrogen-doped carbon polyhedrons were constructed, and doped transition-metal domains were deliberately introduced on the surface. Theoretical investigations show that their energy level can be finely tuned via direct transition-metal doping engineering. As a prototype, an Fe-doped NiCo₂O₄ nanosheets wrapped hollow nitrogen-doped carbon polyhedron (Fe–NiCo₂O₄@HNCP) exhibits outstanding bifunctional electrocatalytic performances with low overpotentials (η = 270 mV for OER, η = 84 mV for HER), low Tafel slopes (b = 42 mV dec⁻¹ for OER, b = 47 mV dec⁻¹ for HER), and high durability. The enhanced performance is attributed to the synergistic effects of energy level matching for electron transfer, and partial charge delocalization-induced rich active sites for reactant adsorption via thermodynamic and kinetic acceleration. This work may open a new pathway to design highly active and stable transition-metal doped electrocatalysts by manipulated energy levels for efficient overall water splitting. We are really grateful for the financial support from the National Natural Science Foundation of China (51433001, 21674019, 21604010), the Science and Technology Commission of Shanghai Municipality (16520722100), the Program of Shanghai Academic Research Leader (17XD1400100), the “Chenguang Program” supported by the Shanghai Education Development Foundation and Shanghai Municipal Education Commission (16CG39) and the Engineering and Physical Sciences Research Council (EPSRC, EP/L015862/1). The computational center of USTC is acknowledged for computational support.

The first priority of drug combination therapy in the treatment of cancer is to achieve enhanced therapeutic efficacy and reduced side effects. The main issue in drug combination therapy is the inscrutable interaction between different drug components. Herein, we developed a multicompartmentalized architecture as a new delivery system. A host liposome encapsulates multiple guest liposomes, where various drug components were loaded into disparate compartments separately. This strategy avoids the interaction among different components before their arrival at the targeting sites and provides the fixed drug combination ratio as needed. Doxorubicin (DOX) and 5-fluorouacil (5FU) loaded smaller liposomes were encapsulated into bigger liposomes with a fixed dose ratio of DOX to 5FU. In vivo tumor growth inhibition by vesosomes was evaluated in HeLa tumor-bearing nude mice, which confirms the enhancement of the delivery system on the synergism of the drug combination.

Biological membrane plays an important role in maintaining an osmotic equilibrium between the cytoplasm and the extracellular solution of cells. Here, the giant unilamellar vesicles (GUVs) as cell models were used to investigate the effect of osmotic stress on phospholipid membranes. The deformation of GUVs, including inward budding and outward budding, was systematically investigated by the osmotic press from glucose, sucrose, LiCl, and KCl solutions. The permeability (P) of DMPC, DMPC/10 mol% Chol GUVs, DMPC/25 mol% Chol GUVs, and DMPC/40 mol% Chol GUVs in glucose, sucrose, LiCl, and KCl solutions were all obtained. The P value decreases with the addition of more cholesterol in the bilayer. The monovalent cations caused higher permeability of lipid bilayer membranes due to their combination with phospholipids. The molar flux of water (J) value was found to be the key factor for determining the deformation state from mainly inward budding to mainly outward budding. The findings in this paper may help us to understand cell transformation triggered with osmotic stress.

Hydrogen evolution reaction (HER) has been severely suppressed by the first proton adsorption step, due to the “shackles” of the surrounding water in the form of hydronium ions (H13O6+). Here, it has been found anionic vacancies in NiCo2A4 (A = O, S, Se) can weaken the shackles of surrounding water in H13O6+, resulting into efficient capture of H+ to form a H+-enriched field. Taking selenium vacancy-rich NiCo2Se4 nanowires on nitrogen-doped carbon nanofibers as an example, it displays higher electrocatalytic activities with low overpotential of 168 mV at 10 mA cm−2 and a Tafel slope of 49.8 mV dec−1. The HER performance is strongly related to the anionic vacancy size, the larger the anionic vacancy size is (VSe > VS > VO), the higher the HER activity does. Guided by density functional theory calculations, it is found that the point defect structures can not only strengthen its interfacial linkage force with H+ by weakening the hydration force of contiguous hydronium ion, but also increase its charge density for efficient electron transfer to adsorbed H+. Therefore, this work creates a useful strategy to optimize the HER performance of traditional bimetallic compounds by engineering the solid-liquid-gas three-phase interfacial interaction.

Electrochemical nitrogen-to-ammonia conversion by the nitrogen reduction reaction (NRR) under ambient conditions is regarded as a potential approach to tackle the energy-intensive Haber–Bosch process with excessive CO2 emission. However, the NRR is still restricted by low faradaic efficiency and NH3 yield, which is due to the chemical inertness of N-related groups for efficient adsorption/activation on the electrocatalysts. Here, a series of spinel-structured nanosheet wrapped hollow nitrogen-doped carbon polyhedra with abundant oxygen vacancies are constructed successfully. From theoretical aspects, these materials show increased charge density on their surface for enhanced capture and activation of N2 molecules. As a result, oxygen vacancy-rich NiCo2O4 on hollow N-carbon polyhedra (Vo-rich NiCo2O4@HNCP) shows outstanding electrocatalytic NRR performance with high production yield (NH3: 4.1 μg h−1 cm−2/17.8 μg h−1 mg−1; faradaic efficiency: 5.3%) and high stability under ambient conditions and is superior to the counterpart oxygen vacancy-poor electrocatalysts. Oxygen vacancy engineering introduces a new concept for rational design of advanced NRR catalysts for energy conversion systems.

The effect of specific surface area (SSA) of Fe 2 O 3 was investigated while evaluating the raw material of Y 3 Fe 5 O 12 (yttrium iron garnet (YIG)) preparation. For YIG ferrite, the specific surface area of Fe 2 O 3 , rather than average particle size ( D 50 ), was found to markedly affect the mixing homogeneity of powders in the mixing procedure and the magnetic properties. Increasing the specific surface area of Fe 2 O 3 resulted in the increase of the remanence ( B r ) and squareness ratio ( SQR ); meanwhile, it also caused an obvious reduction in coercivity ( H C ) for the sintered specimens. An upgrade in the specific surface area of raw material Fe 2 O 3 could further resulted in a decrease in slurry viscosity in the mixing procedure, which promotes slurry mixing homogeneity and further promotes reactivity in the calcination and sintering processes. Consequently, a larger B r and SQR and a smaller H C were obtained. In addition, good ferromagnetic resonance (FMR) line width (i.e., Δ H ) properties were also realized as 36.7 Oe at 3.2 GHz using the selected Fe 2 O 3 . As found in this study, the strict control of raw material Fe 2 O 3 is critical in tailoring suitable B r and H C for the YIG ferrite manufacturing process.

The fabrication of artificial cells containing nature components is challenging. Herein we construct a thylakoid containing artificial cell (TA-cell) by forming multicompartmental structure inside giant unilamellar vesicles (GUVs) using osmotic stress. The thylakoids are selectively loaded inside each compartment in GUVs to mimic “chloroplast”. The TA-cells are able to carry out photosynthesis upon light on. The TA-cells keep their 50% functionality of electron transfer for 12 days, which is twice of those of free thylakoids. Using TA-cells the inhibition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and heavy metal ions (Hg2+, Cu2+, Cd2+, Pb2+ and Zn2+) on the electron transfer process in TA-cells is systematically investigated. Their half maximal inhibitory concentration (IC50) values are 36.23 ± 1.87, 0.02 ± 0.01, 0.42 ± 0.08, 0.82 ± 0.12, 1.97 ± 0.21, and 4.08 ± 0.18 μM, respectively. Hg2+ is the most toxic ion for the photosynthesis process among these five heavy metal ions. This biomimetic syste...

Doxorubicin, one of the most effective antitumor drugs, causes serious adverse cardiac effects. As a derivative of tanshinone IIA, sodium tanshinone IIA sulfonate was exploited for curing cardiovascular disorders. The synergistic effect of the above drugs as a combination was investigated for treating cancer cells and attenuating myocardial apoptosis. A multicompartmentalized vesosome (MCV) was produced to co-deliver the drug combination. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and western blotting analysis demonstrated that the MCV can enhance the synergistic effect of the drug combination and promote the protection of STS in Dox-induced cardiomyocyte apoptosis.

Purpose The purpose of this paper is to develop and empirically test a conceptual framework to analyze how inter-organizational knowledge sharing facilitates enterprise resource planning (ERP) implementation. Design/methodology/approach Data were collected from a 2014 survey on 283 Chinese companies. Structural equation modeling was used to test the structural model of the framework. Findings The results of the study indicated that organizational preparedness (in terms of internal culture, organizational structure, availability of resources, and technological capabilities), positive benefits and costs perception, and external influences (in terms of environmental uncertainty, competitive pressure, and partner readiness) would facilitate inter-organizational knowledge sharing, which in turn, would enhance ERP implementation effectiveness. Research limitations/implications Convenience samples from an author’s MBA classes were used in the survey, and a single respondent from each organization answering all questions for such complicated issues also posed the risk of measurement bias and inaccuracy. Practical implications The study provided evidences to practitioners about how organizations should collaborate with supply chain partners at a full scale in knowledge generation, maintenance, dissemination, and application in order to enhance their effectiveness on ERP implementation. Originality/value ERP projects are predominately observed in existing research as internal initiatives that companies take independently within their own organizational boundaries. This study represents one of the early large-scale empirical efforts to investigate ERP implementation from an inter-firm supply chain collaboration perspective. Additional contribution includes some interesting empirical evidences on the current state of ERP utilization in the Chinese market.

Many of the nominal-the-best quality characteristics of important machine tool components, such as inner or outer diameters, have asymmetric tolerances. An asymmetric tolerance index is a function for the average of the process and the standard deviation. Unfortunately, it is difficult to obtain the 100(1−α)% confidence interval of the index. Therefore, this study adopts Boole’s inequality and DeMorgan’s theorem to find the combined confidence region for the average of the process as well as the standard deviation. Next, using the asymmetric tolerance index for the target function and the combined confidence region for the feasible region, this study applies mathematical programming to find the confidence interval as well as employs this confidence interval for statistical hypothesis testing. Lastly, this study demonstrates the applicability of the proposed approach with an illustrative example.

Lithium-sulfur (Li–S) batteries have been regarded as one kind of the most attractive candidates for next-generation energy storage devices for their high theoretical energy density and fairly low cost. However, the “shuttle effect” caused by diffusion of soluble polysulfides and uncontrollable growth of lithium dendrite seriously deteriorate the long-term cycle stability and safety of Li–S batteries in practical applications. Herein, a highly porous polyvinyl alcohol (PVA)/sodium carboxylmethyl cellulose (CMC) composite separator with three-dimensional ion-selective nanochannels has been successfully fabricated via a facile non-solvent induced separation method. The abundant negative –COO- groups inside the nanochannels can hinder the undesired polysulfides penetrating through the separator, but allow Li+ transporting rapidly and induce uniform lithium stripping/plating. As a result, the Li–S battery using the porous PVA/CMC composite separator realizes stable cycling with a low decay rate of 0.045% per cycle over 500 cycles at 1 C. This work offers a feasible strategy to design advanced multifunctional Li–S battery separators.

An ideal nanotheranostic agent should be able to achieve efficient tumor accumulation, retention, and fast elimination after its theranostic functions exhausts. However, there is an irreconcilable contradiction on optimum sizes for effective tumor retention and fast elimination. Herein, a programmed size-changeable nanotheranostic agent based on polyprodrug-modified iron oxide nanoparticles (IONPs) and aggregation-induced emission photosensitizer is developed for enhanced magnetic resonance imaging (MRI)-guided chemo/photodynamic combination therapy. The nano-sized theranostic agents with an initial diameter of about 90 nm can accumulate in tumor tissue through passive targeting. In the acidic tumor microenvironment, large aggregates of IONPs are formed, realizing enhanced tumor retention and MR signal enhancement. Under the guidance of MRI, light irradiation is applied to the tumor site for triggering the generation of reactive oxygen species and drug release. Moreover, after chemo/photodynamic combination therapy, the large-sized aggregates are re-dispersed into small-sized IONPs for fast elimination, reducing the risk of toxicity caused by long-term retention. Therefore, this study provides a promising size-changeable strategy for the development of nanotheranostic agents.

In order to maximize the value of an organization's data assets, it is important to keep data in its databases up-to-date. In the era of big data, however, constantly changing data sources make it a challenging task to assure data timeliness in enterprise systems. For instance, due to the high frequency of purchase transactions, purchase data stored in an enterprise resource planning system can easily become outdated, affecting the accuracy of inventory data and the quality of inventory replenishment decisions. Despite the importance of data timeliness, updating a database as soon as new data arrives is typically not optimal because of high update cost. Therefore, a critical problem in this context is to determine the optimal update policy for database systems. In this study, we develop a Markov decision process model, solved via dynamic programming, to derive the optimal update policy that minimizes the sum of data staleness cost and update cost. Based on real-world enterprise data, we conduct experiments to evaluate the performance of the proposed update policy in relation to benchmark policies analyzed in the prior literature. The experimental results show that the proposed update policy outperforms fixed interval update policies and can lead to significant cost savings.

In order to increase the loading efficiency of drug carriers, here we demonstrated a microfluidic method to fabricate an asymmetric vesicle, which contains trichloro(1H,1H,2H,2H-perfluoroocty-l)silane (TPS) inner leaflet and lipid outer leaflet. The asymmetric vesicle was characterised by fluorescence microscopy and Fourier transform infra-red spectrum. In vitro cytotoxicity of the vesicles carrying 5-fluorouacil (5-FU) has also been studied.

Schizophrenia is associated with disrupted cognitive control and sleep-wake cycles. Here we identify diurnal rhythms in gene expression in the human dorsolateral prefrontal cortex (dlPFC), in schizophrenia and control subjects. We find significant diurnal (24 h) rhythms in control subjects, however, most of these transcripts are not rhythmic in subjects with schizophrenia. Instead, subjects with schizophrenia have a different set of rhythmic transcripts. The top pathways identified in transcripts rhythmic only in subjects with schizophrenia are associated with mitochondrial function. Importantly, these rhythms drive differential expression patterns of these and several other genes that have long been implicated in schizophrenia (including BDNF and GABAergic-related transcripts). Indeed, differential expression of these transcripts is only seen in subjects that died during the night, with no change in subjects that died during the day. These data provide insights into a potential mechanism that underlies changes in gene expression in the dlPFC with schizophrenia., Sleep disturbance is common in psychiatric disease, and this may contribute to altered circadian rhythm in gene expression. Here the authors show that rhythms in gene expression in the dorsolateral prefrontal cortex in schizophrenia are different to that seen in healthy controls.

Nowadays, network intrusion detection is researched extensively due to increasing global network threats. Many researchers propose to incorporate machine learning techniques in network intrusion detection systems since these techniques allow for automated intrusion detection with high accuracy. Furthermore, dimensionality reduction techniques can improve the performance of machine learning models, and as such, are widely used as a pre-processing step. Nevertheless, many researchers consider machine learning techniques as a black box because of its complex intrinsic mechanism. Visualization plays an important role in facilitating the understanding of such sophisticated techniques because visualization is able to offer intuitive meaning to the machine learning results. This research investigates the performance of two dimensionality reduction techniques on network intrusion detection datasets. In addition, this work also demonstrates visualizing the resulting data in 3-dimensional space. The purpose of this is to possibly gain insight into the results, which can potentially aid in the improvement of machine learning performance.

With the increasing threat of cyber attacks, machine learning techniques have been researched extensively in the area of network intrusion detection. Such techniques can potentially provide a means for the real-time automated detection of attacks and abnormal traffic patterns. However, misclassification is a common problem in machine learning techniques for intrusion detection, and a lack of insight into why such misclassification occurs impedes the improvement of machine learning models. This paper presents an approach to visualizing network intrusion detection data in 3D. The purpose of this is to facilitate the understanding of network intrusion detection datasets using a visual representation to reflect the geometric relationship between various categories of network traffic. This can potentially provide useful insight to aid the design of machine learning techniques. This paper demonstrates the usefulness of the proposed 3D visualization approach by presenting results of experiments on commonly used network intrusion detection datasets.

Resveratrol in Polygonum cuspidatum is a β-glycoside, which can be hydrolyzed to resveratrol by β-glucosidase. it is an efficient production process to degrade polydatin from Polygonum cuspidatum extract by immobilized β-glucosidase. It is of great significance to explore suitable immobilization conditions to improve the catalytic efficiency and reusability of β-glucosidase for polydatin degradation and cost reduction. In this paper, the recombinant Escherichia coli bgl2238, which was screened and constructed from corn soil of Heilongjiang Province in the early laboratory, was immobilized by chitosan adsorption and glutaraldehyde crosslinking. The preparation conditions and immobilization process of bgl2238 were determined by single factor method: the optimal crosslinking time was 1 h, the optimal crosslinking temperature was 20 °C, the recovery rate of enzyme activity of bgl2238 was 87 %, and the enzyme activity was 859.65 mU/g. The optimum temperature of the immobilized bgl2238 is 50 °C, which is 6 °C higher than that of the free bgl2238, and the temperature stability and pH stability are improved. After six consecutive hydrolysis of Polygonum cuspidatum, the degradation rate of polydatin is still over 70 %, which proves that the immobilized bgl2238 has good reusability. This will be helpful to evaluate the application prospect of β - glucosidase immobilized in this system and determine the best conditions for its production.

The sodium-ion storage property in two-dimensional transition metal dichalcogenides (TMDs) is still seriously confined due to the lacking of efficient pathways for Na+ insertion, which enlightens the construction of multi-dimensional ion channels a necessary. Herein, we prepared interlayer defect, sulfur vacancy-contained ReS2 nanosheets on porous nitrogen-doped carbonized bacterial cellulose (dr-ReS2-x/NCBC). In such dual-defect configuration, the interlayer defects provide interconnected in-plane/interlamination channels for offering extra pathways of Na+ insertion/extraction and shortening ionic diffusion distance, while the sulfur vacancy could further enhance the electronic conductivity and induce more active sites for Na+ storage. Therefore, the dr-ReS2-x/NCBC anode displays an enhanced rate capacity (231.2 mAh g−1 at 5 A g−1) and a good cycling stability (187.3 mAh g−1 at 5 A g−1 after 500 cycles). Furtherly revealed by density functional theory calculations, the sodium-ion storage property is attributed to its negatively shifted binding energy for sodium ions (from −0.771 to −1.791/-1.244 eV), and alleviated structural change (from 5.8% to 3.4%/-1.6%) during sodiation/desodiation processes. The dr-ReS2-x/NCBC anode was also assembled coupling with Na3V2(PO4)3 cathode as a sodium-ion full cell for practical applications. This work is expected to offer an in-depth understanding between dual-defect engineering in TMDs-based anodes and as-enhanced sodium-storage performance.

A method is presented for the online prediction of the terrain-shearing parameters for a wheeled Unmanned Ground Vehicles (UGVs) traversing on an unknown terrain. The method uses a trained multiple-output least squares support vector machine (LS_SVM) to map engineering data and predict the terrain-shearing parameters such as cohesion, internal friction angle and shear deformation modulus without requiring information on wheel sinkage. The predicted terrain-shearing parameters can be used to predict vehicle drawbar pull which can be used for trafficability prediction, traction control and performance optimization. Experiments were performed using a single-wheel soil bin to measure the sinkage, drawbar pull and torque for a griddle net wheel under different slip ratio. An additional experiment was performed under a continuous slip ratio from 0.2 to 0.6 with a wheel load of 50 N to validate the method. The experimental results show that the multiple output LS_SVM model can accurately predict the terrain-shearing parameters using the slip ratio, torque and wheel load without the need of wheel sinkage.

Stimuli-responsive drug carriers are considered to play important roles in chemotherapy. We fabricated pH-sensitive polydopamine-protected liposomes (liposome@PDA) drug delivery systems, which were characterised with microscope, scanning electron microscope (SEM), UV-vis spectrometer and Fourier transform infrared (FTIR) technieques. The typical chemotherapeutic agent, 5-fluorouracil (5-FU), was loaded into liposome@PDA capsules. The maximum release percentages of 5-FU are 3.2%, 29.5%, 52.7%, 76.7% in the solution with pH 7.42, 6.87, 4.11 and 3.16, respectively. The in vitro cell cytotoxity experiments were carried out using 5-FU-loaded capsules at pH 6.87 solution, which simulate the true pH around cancerous cells. At 1.5 μM concentration, the free 5-FU, 5-FU-loaded liposome capsules and 5-FU-loaded capsules showed the cell viability of 50.56%, 22.66% and 21.63%, respectively. It confirms that drug-loaded capsules performed better than free drug. The results demonstrate the great potential of liposome@PDA capsules as carriers in biomedical applications.

A nanocomposite consisting of zinc sulfide quantum dots and polyaniline (ZnSQD@PANI) was placed on a gold electrode along with antibody against clenbuterol to give an amperometric immunosensor for clenbuterol. Compared to the use of pristine PANI, the electrode modified with the ZnSQD@PANI nanocomposite adsorbs clenbuterol antibody much better and therefore exhibits higher sensitivity to clenbuterol. The biosensor, when operated at a working potential of 0.21 V (vs. Ag/AgCl), displays a detection limit as low as 5.5 pg⋅mL−1 and works over the 0.01 to 10 ng⋅mL−1 concentration range. Related species such as salbutamol and ractopamine, urine components such as urea and uric acid, and the ions Ca(II), Na(I), and K(I) do not interfere.

The construction of advanced micro-supercapacitors (MSCs) with both wide working-voltage and high energy density is promising but still challenging. In this work, a series of nitrogen-doped, cross-coupled micro-mesoporous carbon-metal networks (N-STC/Mx Oy ) is developed as robust additives to 3D printing inks for MSCs fabrication. Taking the N-STC/Fe2 O3 nanocomposite as an example, both experimental results and theoretical simulations reveal that the well-developed hierarchical networks with abundantly decorated ultrafine Fe2 O3 nanoparticles not only significantly facilitate the ion adsorption at its three-phase boundaries (Fe2 O3 , N-STC, and electrolyte), but also greatly favor ionic diffusion/transport with shortened pathways. Consequently, the as-prepared N-STC/Fe2 O3 electrode delivers a high gravimetric capacitance (267 F g-1 at 2 mV s-1 ) and outstanding stability in a liquid-electrolyte-based symmetric device, as well as a record-high energy density of 114 Wh kg-1 for an asymmetric supercapacitor. Particularly, the gravimetric capacitance of the ionogel-based quasi-solid-state MSCs by 3D printing reaches 377 F g-1 and the device can operate under a wide temperature range (-10 to 60 °C).

The lack of precise control of particle sizes is the critical challenge in the assembly of 3D interconnected transition-metal oxide (TMO) for newly-emerging energy conversion devices. A self-embedded templating strategy for preparing the TMO@carbon quasiaerogels (TMO@C-QAs) is proposed. By mimicking an aerogel structure at a microscale, the TMO@C-QA successfully assembles size-controllable TMO nanoparticles into 3D interconnected structure with surface-enriched carbon species. The morphological evolutions of intermediates verify that the self-embedded Ostwald ripening templating approach is responsible for the dual-channel TMO@C-QA formation. The general self-embedded templating strategy is easily extended to prepare various TMO@C-QAs, including the Co3O4@C-QA, Mn3O4@C-QA, Fe2O3@C-QA, and NiO@C-QA. Benefiting from the unparalleled 3D interconnected network of aerogels, the Co3O4@C-QA displays superior bifunctional catalytic activities for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), as well as high specific capacity and excellent long-term stability for lithium-ion battery (LIB) anode. A proof-of-concept battery-powered electrolyzer with Co3O4@C-QA cathode and anode powered by a full LIB with Co3O4@C-QA anode is presented. The battery-powered electrolyzer made of the state-of-the-art TMOs can exhibit great competitive advantages due to its supreme multifunctional energy conversion performance for future water electrolysis.

Electrocatalytic nitrogen reduction reaction (NRR) and hydrogen evolution reaction (HER) are intriguing approaches to nitrogen fixation and hydrogen production under ambient conditions, given the need to discover efficient and stable catalysts to light up the “green chemistry” future. However, bottlenecks are often found during N2/H2O activation, the very first step of NRR/HER, due to energetic electron injection from the surface of electrocatalysts. It is reported that the bottlenecks for both NRR and HER can be tackled by engineering the energy level via low‐valent transition‐metal doping, simultaneously, where rhenium disulfide (ReS2) is employed as a model platform to prove the concept. The doped low‐valent transition‐metal domains (e.g., Fe, Co, Ni, Cu, Zn) in ReS2 provide more active sites for N2/H2O chemisorption and electron transfer, not only weakening the NN/OH bonds for easier dissociation through proton coupling, but also elevating d‐band center toward the Fermi level with more electron energy for N2/H2O reduction. As a result, it is found that iron‐doped ReS2 nanosheets wrapped nitrogen‐doped carbon nanofiber (Fe‐ReS2@N‐CNF) catalyst exhibits superior electrochemical activity with eightfold higher ammonia production yield of 80.4 µg h−1 mg−1cat., and lower onset overpotential of 146 mV and Tafel slope of 63 mV dec−1, when comparing with the pristine ReS2.

The success of nanoparticulate formulations in drug delivery depends on various aspects including their toxicity, internalization, and intracellular location. Vesicular assemblies consisting of phospholipids and amphiphilic block copolymers are an emerging platform, which combines the benefits from liposomes and polymersomes while overcoming their challenges. We report the synthesis of poly(cholesteryl methacrylate)-block-poly(2-(dimethylamino) ethyl methacrylate) (pCMA-b-pDMAEMA) block copolymers and their assembly with phospholipids into hybrid vesicles. Their geometry, their ζ-potential, and their ability to adsorb onto polymer-coated surfaces were assessed. Giant unilamellar vesicles were employed to confirm the presence of both the phospholipids and the block copolymer in the same membrane. Furthermore, the cytotoxicity of selected hybrid vesicles was determined in RAW 264.7 mouse macrophages, primary rat Kupffer cells, and human macrophages. The internalization and lysosomal escape ability of the hybrid vesicles were confirmed using RAW 264.7 mouse macrophages. Taken together, our findings illustrate that the reported hybrid vesicles are a promising complementary drug delivery platform for existing liposomes and polymersomes.

The use of free-standing carbon-based hybrids plays a crucial role to help fulfil ever-increasing energy storage demands, but is greatly hindered by the limited number of active sites for fast charge adsorption/desorption processes. Herein, an efficient strategy is demonstrated for making defect-rich bismuth sulfides in combination with surface nitrogen-doped carbon nanofibers (dr-Bi2 S3 /S-NCNF) as flexible free-standing electrodes for asymmetric supercapacitors. The dr-Bi2 S3 /S-NCNF composite exhibits superior electrochemical performances with an enhanced specific capacitance of 466 F g-1 at a discharge current density of 1 A g-1 . The high performance of dr-Bi2 S3 /S-NCNF electrodes originates from its hierarchical structure of nitrogen-doped carbon nanofibers with well-anchored defect-rich bismuth sulfides nanostructures. As modeled by density functional theory calculation, the dr-Bi2 S3 /S-NCNF electrodes exhibit a reduced OH- adsorption energy of -3.15 eV, compared with that (-3.06 eV) of defect-free bismuth sulfides/surface nitrogen-doped carbon nanofiber (df-Bi2 S3 /S-NCNF). An asymmetric supercapacitor is further fabricated by utilizing dr-Bi2 S3 /S-NCNF hybrid as the negative electrode and S-NCNF as the positive electrode. This composite exhibits a high energy density of 22.2 Wh kg-1 at a power density of 677.3 W kg-1 . This work demonstrates a feasible strategy to construct advanced metal sulfide-based free-standing electrodes by incorporating defect-rich structures using surface engineering principles.

Network Intrusion Detection Systems (NIDS) are essential to combat security threats in network environments. These systems monitor and detect malicious behavior to provide automated methods of identifying and dealing with attacks or security breaches in a network. Machine learning is a promising approach in the development of effective NIDS. One of the problems faced in the development of such systems is that the datasets used in the construction of classifiers are typically imbalanced. This is because the classification categories do not have relatively equal representation in the datasets. This study investigates a two-stage classifier approach to NIDS based on imbalanced intrusion detection datasets by separating the training and detection of minority and majority intrusion classes. The purpose of this is to allow flexibility in the classification process, for example, two different classifiers can be used for detecting minority and majority classes respectively. In this paper, we performed experiments using the random forests classifier and the contemporary UNSW-NB15 dataset was used to evaluate the effectiveness of the proposed approach.

Free-form reticulated shells should not only satisfy the requirement of a specific geometric configuration but also have rational mechanical properties. This article introduced two form-finding methods of free-form configuration. The first method was a reverse realization method that is based on hanging fabric with a given boundary condition; the second method was a numerical simulation method that is based on the equilibrium characteristics of a natural tension membrane combined with a geometrical characteristics analysis and a mechanical properties optimization. The article then discusses the conducted beneficial comparison. The analytical results demonstrate that both these form-finding methods are feasible for obtaining rational free-form shells, and the numerical simulation method is more convenient for obtaining the surface family.

The quality of master data is crucial for the accurate functioning of the various modules of an enterprise resource planning ERP system. This study addresses specific data problems arising from the generation of approximately duplicate material records in ERP databases. Such problems are mainly due to the firm’s lack of unique and global identifiers for the material records, and to the arbitrary assignment of alternative names for the same material by various users. Traditional duplicate detection methods are ineffective in identifying such approximately duplicate material records because these methods typically rely on string comparisons of each field. To address this problem, a machine learning-based framework is developed to recognise semantic similarity between strings and to further identify and reunify approximately duplicate material records – a process referred to as de-duplication in this article. First, the keywords of the material records are extracted to form vectors of discriminating words. Second, a machine learning method using a probabilistic neural network is applied to determine the semantic similarity between these material records. The approach was evaluated using data from a real case study. The test results indicate that the proposed method outperforms traditional algorithms in identifying approximately duplicate material records.

As promising drug delivery vehicles, previous investigations of liposomes as carriers are primarily focused on insertion and modification of lipid membrane interfaces. The utility of the inner core seems to be overlooked. Herein, we developed pH-sensitive liposomes (PSLs) containing an aqueous two phase system (ATPS), and intriguingly discovered their hierarchical release under acidic stimuli. ATPS containing two polymers (poly(ethylene glycol) (PEG) and dextran) is homogeneous above phase transition temperature when producing ATPS-liposomes, and separated into PEG-rich phase and dextran-rich phase after cooling down to room temperature. The overall release time of ATPS-liposomes is divided into two stages and prolonged compared to simple aqueous liposomes. The unique release profile is due to the disproportional distribution of drugs in two phases. Doxorubicin (DOX) is loaded in the ATPS-liposomes, and their half maximum inhibition concentration on HeLa cells is 0.018 μmol L-1, which means 27.5 fold increase in inhibition efficiency over free DOX.

The use of artificial cells has attracted considerable attention in various fields from biotechnology to medicine. Here, we develop a cell-sized vesicle-in-vesicle (VIV) structure containing a separate inner vesicle (IV) that can be loaded with DNA. We use polymerase chain reaction (PCR) to successfully amplify the amount of DNA confined to the IV. Subsequent osmotic stress-induced fission of a mother VIV into two daughter VIVs successfully divides the IV content while keeping it confined to the IV of the daughter VIVs. The fission rate was estimated to be ∼20% quantified by fluorescence microscope. Our VIV structure represents a step forward toward construction of an advanced, fissionable cell model.

The rapid growth in Internet and communication technology has facilitated an escalation in the exchange of digital multimedia content. This has resulted in an increase in copyright infringement, which has led to a greater demand for more robust copyright protection mechanisms. Digital watermarking is a means of detecting ownership and illegal use of digital products. This paper presents an approach to watermarking images by embedding QR code information in a digital image. The notion of the proposed scheme is to capitalize on the error correction mechanism that is inherent in the QR code structure, in order to increase the robustness of the watermark. By employing the QR code’s error correction mechanism, watermark information contained within a watermarked image can potentially be decoded even if the image has been altered or distorted by an adversary. This paper studies the characteristics of the proposed scheme and presents experiment results examining the robustness and security of the QR code watermarking approach.

Variable stiffness actuation (VSA) has been paid more attention to as a novel actuating class for robotics to change the apparent output stiffness. However, most designs internally present a set of elastic elements. This paper proposes a novel VSA based on a brief planetary with dual motor inputs, and presents some variable stiffness analyses based on power flow, torque, force and motor performance. It is shown that, when the VSA is driven by differential drives, the stiffness is determined by the external load (load force, load velocity and force impact) and the internal inputs (motor voltage, torque performance and electrical characteristics). In particular, the VSA can be manipulated by controlling motor performance without common elastic elements and complex mechanism.

An ultrasonic image speckle noise removal method by using total least squares model is proposed and applied onto images of cardiovascular structures such as the carotid artery. On the basis of the least squares principle, the related principle of minimum square method is applied to cardiac ultrasound image speckle noise removal process to establish the model of total least squares, orthogonal projection transformation processing is utilized for the output of the model, and the denoising processing for the cardiac ultrasound image speckle noise is realized. Experimental results show that the improved algorithm can greatly improve the resolution of the image, and meet the needs of clinical medical diagnosis and treatment of the cardiovascular system for the head and neck. Furthermore, the success in imaging of carotid arteries has strong implications in neurological complications such as stroke.

Cave animals are often adapted to digging and life underground, with claw toes similar in structure and function to a sampling scoop. In this paper, the clawed toes of the Himalayan marmot were selected as a biological prototype for bionic research. Based on geometric parameter optimization of the clawed toes, a bionic sampling scoop for use on Mars was designed. Using a 3D laser scanner, the point cloud data of the second front claw toe was acquired. Parametric equations and contour curves for the claw were then built with cubic polynomial fitting. We obtained 18 characteristic curve equations for the internal and external contours of the claw. A bionic sampling scoop was designed according to the structural parameters of Curiosity’s sampling shovel and the contours of the Himalayan marmot’s claw. Verifying test results showed that when the penetration angle was 45° and the sampling speed was 0.33 r/min, the bionic sampling scoops’ resistance torque was 49.6% less than that of the prototype sampling scoop. When the penetration angle was 60° and the sampling speed was 0.22 r/min, the resistance torque of the bionic sampling scoop was 28.8% lower than that of the prototype sampling scoop.