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Listeria monocytogenes (L. monocytogenes) is a ubiquitous foodborne pathogens responsible for listeriosis, which is associated with high morbidity and mortality. Development of simple and fast methods for L. monocytogenes detection is of great needed. In this study, we present a simple method for L. monocytogenes detection combined aptamers decorated magnetic beads for selective capture and gold nanoparticles (AuNPs) mediated signal amplication. A NH2 labeled aptamer specific to L. monocytogenes was decorated on magnetic beads for selective capture and isolation of L. monocytogenes from food sample. AuNPs was functionalized with sulfhydryl modified primers specific to hly gene of L. monocytogenes in acidic environments. The AuNP@primers could catalyze TMB-H2O2 to TMB2+ and generate a significant blue color, this reaction was found to be enhanced by DNA. AuNP@primers was used as a signal indicator for the presence of L. monocytogenes DNA by enhancing the catalytic reaction of TMB-H2O2. The colour change was observed by naked eye and the optical density of TMB2 + was analyzed to quantify the result. The developed assay was highly specific and the limit of detection was 101 CFU/mL of L. monocytogenes. For the detection of L. monocytogenes in spiked food samples, the recoveries were ranging from 73.63 to 84.21% with the coefficient of variation less than 2.41% in meat, and ranged from 94.13 to 100.71% with the coefficient of variation less than 2.82% in milk, respectively. Therefore, the developed colorimetric assay is suitable for food sample testing, the detection takes less than 1.5 h, which enables on-site screening. This study offers a promising approach for rapid, sensitive and accurate detection of L. monocytogenes in food. [ABSTRACT FROM AUTHOR]

This study delves into the interplay between learning motivation, organizational performance, and the innovative climate within Chinese firms. It is a subject of frequent discussion in literature but there is little concrete evidence supporting this viewpoint within the context of small and medium size enterprises in China. Drawing upon a comprehensive review of existing literature and empirical data gathered, this research aims to uncover the connections between employee learning motivation and its impact on the organizational dynamics in the context of Chinese firms. A cross sectional survey is used to collect the data of 115 Chinese firms and structural equation modelling (SEM) is used for empirical analysis. The results show that success of firms in terms of innovation is significantly influenced by organizational learning motivation. Moreover, innovative environment of the firms increases the overall performance of the organizations. It is also found that factors affecting the innovations have a significant impact on organizational performance. The findings of the study suggest that firms should develop organizational learning motivation to boost their innovation capability and overall performance. This study offers insights and recommendations for organizations and policymakers seeking to harness the potential of learning motivation to drive sustainable growth, competitiveness, and innovation in Chinese firms. [ABSTRACT FROM AUTHOR]

Using biodegradable films as a substitute for conventional polyolefin films has emerged as a crucial technology to combat agricultural white pollution. To address the shortcomings in the tensile strength, water vapor barrier properties, and degradation period of PBAT-based biodegradable films, this investigation aimed to create a composite film that could improve the diverse properties of PBAT films. To achieve this, a PBAT/PLA-PPC-PTLA ternary blend system was introduced in the study. The system effectively fused PBAT with PLA and PPC, as evidenced by electron microscopy tests showing no apparent defects on the surface and cross-section of the blended film. The developed ternary blend system resulted in a 58.62% improvement in tensile strength, a 70.33% enhancement in water vapor barrier properties, and a 30-day extension of the functional period compared to pure PBAT biodegradable films. Field experiments on corn crops demonstrated that the modified biodegradable film is more suitable for agricultural production, as it improved thermal insulation and moisture retention, leading to a 5.45% increase in corn yield, approaching the yield of traditional polyolefin films. [ABSTRACT FROM AUTHOR]

Bemisia tabaci is distributed globally and incurs considerable economic and ecological costs as an agricultural pest and viral vector. The entomopathogenic fungus Metarhizium anisopliae has been known for its insecticidal activity, but its impacts on whiteflies are understudied. We investigated how infection with the semi-persistently transmitted Cucurbit chlorotic yellows virus (CCYV) affects whitefly susceptibility to M. anisopliae exposure. We discovered that viruliferous whiteflies exhibited increased mortality when fungus infection was present compared to non-viruliferous insects. High throughput 16S rRNA sequencing also revealed significant alterations of the whitefly bacterial microbiome diversity and structure due to both CCYV and fungal presence. Specifically, the obligate symbiont Portiera decreased in relative abundance in viruliferous whiteflies exposed to M. anisopliae. Facultative Hamiltonella and Rickettsia symbionts exhibited variability across groups but dominated in fungus-treated non-viruliferous whiteflies. Our results illuminate triangular interplay between pest insects, their pathogens, and symbionts—dynamics which can inform integrated management strategies leveraging biopesticides This work underscores the promise of M. anisopliae for sustainable whitefly control while laying the groundwork for elucidating mechanisms behind microbe-mediated shifts in vector competence. [ABSTRACT FROM AUTHOR]

The environment friendly Cu2ZnSnSe4 (CZTSe) quantum dot-sensitized solar cells (QDSSCs) has become one of the most promising photovoltaic technologies due to its earth-abundant component and excellent photoelectric properties. However, the power conversion efficiency (PCE) is far behind other high-efficiency chalcogenide sensitizer systems and the main obstacle can be attributed to the inappropriate conduction band position relative to the TiO2 films. Herein, we developed a partial substitution approach to transform CZTSe QDs to Cu2Zn(SnxGe1−x)Se4 (CZTGSe) QDs to resolve the CBM mismatch problem in QDSSCs. The CZTGSe QDs with narrow size distribution were synthesized via one-step method and Ge/(Ge+Sn) ratios were prepared. It is found that the introduction of Ge upshifts the CBM and broadens the band gap of CZTGSe QDs. Benefiting from the enhanced driving force of photoelectron injection and depressed charge recombination at TiO2/QDs/electrolyte interface, the short-circuit current (Jsc) and open-circuit voltage (Voc) of Ge-substituted QDSSCs are synchronously improved and the PCE of the 30% Ge content device finally is increased from 3.83 to 4.42%. This Ge-assisted band engineering approach solves the main obstacle for the further development of panchromatic CZTGSe QDSSCs. [ABSTRACT FROM AUTHOR]

Foodborne pathogens Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli O157:H7 continue to be leading causes of foodborne illness. Herein, we describe a sensitive and reliable lateral flow immunoassay for the simultaneous detection of these three bacteria via multiplex PCR and test strip by using gold nanoparticles (AuNPs) as label. Biotin, FITC and digoxin were used as tags for Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli O157:H7, respectively. AuNPs were conjugated with thiolated probes and detected by multiplex lateral flow strip with three test lines corresponding to the three bacteria. The proposed method exhibited excellent specificity (no cross-reactivity with other tested foodborne bacteria were observed), good precision with the coefficient of variation less than 8.73%, and satisfactory recoveries (82.34–98.34%). The limits of detection were from 0.3 × 101 to 3.5 × 102 CFU mL−1 for the three bacteria in chicken breast sample, without culture enrichment, revealing the feasible and reliable of this method. The developed process, including sample preparation, PCR amplification, AuNPs conjugation and test strip detection, can be completed within 4 h. In light of the high level of targets specificity and sensitivity, this method provides a novel application potential for the simultaneous detection of foodborne pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Nonspecific adsorption has always been a critical challenge for sensor detection; thus, an efficient and facile approach for fabricating antifouling sensors is highly desirable. Here, we developed an antifouling coating on sensor surfaces, conveniently made with a simple drip of phase-transited BSA (PTB) followed by a modification with a peanut allergen antibody, which unexpectedly provides synergistic antifouling properties in sensors. Atomic force microscopy and scanning electron microscopy were used to evaluate the surface evenness. Optimizations in terms of PTB modification time and concentrations were performed using surface plasmon resonance by measuring protein resistance capabilities. Compared to bare Au surfaces, the PTB-modified surfaces exhibited low adsorption against BSA (<10 ng/cm2) and good resistance against lysozyme (Lyz). After immobilizing antibodies, the antifouling performance of the sensor coatings had an obvious enhancement, with almost no BSA adsorption and low lysozyme adsorption. The target recognition was also analyzed to verify the good sensing performance of the antifouling sensor. This understanding of antibody synergy provides suggestions for the development of antifouling sensors. [ABSTRACT FROM AUTHOR]

With the reliance on ocean resources, the nuclear power powers have set their sights on marine nuclear power plants to break through the bottleneck of energy supply for the development of ocean resources. In this paper, the computational fluid dynamics software ANSYS CFX 2021 is used to simulate the TOSQAN benchmark experiment. Three different turbulence models, the k − ε model, R N G   k − ε model, and S S T model, are selected to analyze the adaptability of the turbulence model. The simulation results are compared with the benchmark experimental results, and the selected numerical calculation model is used to analyze the influence of vapor on the pressure, temperature, hydrogen distribution, and hydrogen risk in the containment space when a hypothetical serious accident occurs in a marine nuclear power plant. The results show that the results simulated with the k − ε turbulence model are closer to the benchmark experimental results. Vapor has no obvious effect on the response speed of pressure balance at each position in the closed containment space, and the condensation of the vapor wall can effectively reduce the pressure peak in the closed containment space. The existence of vapor and the increase in vapor concentration will increase the temperature in the closed containment space. The condensation of vapor on the wall surface will cause the temperature in the containment space to have a peak value, which can effectively reduce the temperature in the containment space. Vapor will promote the mixing of gas in the containment space and make the hydrogen distribution tend to be uniform. The presence of vapor and the increase in vapor concentration can reduce the hydrogen risk in the containment space, but the condensation of vapor may increase the hydrogen risk in the containment space. [ABSTRACT FROM AUTHOR]

Herein, a novel core-shell material Fe3O4@MIL-100(Fe) was synthesized for developing a novel LFIA by a two-step solvothermal method with good magnetic properties and high specific surface area. It was used as both magnetic separation and label agents in LFIA for the detection of Listeria monocytogenes. The enrichment of target bacteria can be achieved quickly and easily by direct adsorption of Fe3O4@MIL-100(Fe) on the bacteria and by the action of an applied magnetic field. It was beneficial in separation and concentration of target bacteria from food samples. The Fe3O4@MIL-100(Fe)-bacterial was then detected by the anti-Listeria monocytogenes antibody on the T line under the capillary action of the LFIA strip, resulting in the formation of a visible orange band. Under the optimal conditions, there was a good linear relationship between the intensity of the T line and the quantity of Listeria monocytogenes in the range of 105-108 CFU mL− 1, with a visual detection limit of 3.3 × 106 CFU mL− 1. The strip showed strong specificity for L. monocytogenes, and the detection could be finished in 45 min, without the needing of pre-treatment. Thus, the proposed Fe3O4@MIL-100(Fe)-based strip was simple prepared, label-free, low cost, rapid and convenience. [ABSTRACT FROM AUTHOR]

Anthocyanins (ANs) have strong antioxidant activities and can inhibit chronic diseases, but the instability of ANs limits their applications. The conservation of preheating whey protein concentrate (WPC) on the stability of purple sweet potato ANs was investigated. The retention of ANs in WPC-ANs was 85.88% after storage at 25 °C for 5 h. WPC-ANs had higher retention of ANs in heating treatment. The retention rates of ANs in WPC-ANs exposed to light and UV lamps for 6 h were 78.72% and 85.76%, respectively. When the concentration of H2O2 was 0.50%, the retention rate of ANs in the complexes was 62.04%. WPC-ANs' stability and antioxidant activity were improved in simulated digestive juice. The WPC-ANs connection was static quenching, and the binding force between them was a hydrophobic interaction at one binding site, according to the fluorescence quenching spectroscopy. UV-visible absorption spectroscopy and Fourier transform infrared spectroscopy (FTIR) analysis further indicated that the secondary structure and microenvironment of amino acid residues in WPC can be impacted by the preheating temperature and preheating times of WPC. In conclusion, preheating WPC can successfully preserve the stability of purple sweet potato ANs by binding to them through a non-covalent interaction. [ABSTRACT FROM AUTHOR]

To optimize the bamboo heat treatment process, the corresponding evolution rules under various heat treatment conditions must be determined. When the heat treatment time and temperature remained constant, the effects of different heat treatment pressures on the equilibrium moisture content, dimensional stability, mechanical properties, and chemical composition of bamboo were systematically investigated. In this experiment, bamboo without heat treatment was used as the control group. The experimental findings demonstrate the following: (1) The equilibrium moisture content of heat-treated bamboo gradually decreases with increasing treatment pressure. When the heat treatment pressure was set at 0.1, 0.15, 0.2, and 0.25 MPa, the bamboo's equilibrium water content decreased to 12.1%, 11.7%, 9.9%, and 8.6%, respectively, while that of the control group was 13.8%. (2) The dimensional stability of bamboo was enhanced with increasing heat treatment pressure. At pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the radial air-dry shrinkage rates of the heat-treated bamboo decreased to 3.4%, 3.4%, 2.6%, and 2.3%, respectively, while the tangential air-dry shrinkage rates reduced to 5.6%, 5.1%, 3.3%, and 3.0%. In comparison, the radial and tangential air-dry shrinkage rates of the control group were measured as 3.6% and 5.8%, respectively. Similarly, the radial and tangential full-dry shrinkage of bamboo exhibited a similar trend. (3) With the increase in heat treatment pressure, the bending strength and longitudinal compressive strength of bamboo exhibited an initial rise followed by a decline. When it was at heat treatment pressures of 0.1, 0.15, 0.2, and 0.25 MPa, the corresponding bending strengths of the heat-treated bamboo were measured as 41.2, 26.7, 22.4, and 20.4 MPa, respectively; while the longitudinal compressive strengths were recorded as 42.6, 38.1, 29.1, and 25.3 MPa. In comparison, the bending and longitudinal compressive strengths of the control group were measured as 39.8 and 38.5 MPa, respectively. It is evident that the optimal heat treatment pressure for bamboo is 0.1 MPa, resulting in a significant increase of 3.5% and 10.6% in bending strength and longitudinal compressive strength, respectively, compared to the control group. (4) Based on the FTIR and XRD patterns of bamboo samples, a range of physical and chemical transformations were observed during the heat treatment process, including cellulose adsorb water evaporation, hemicellulose and cellulose degradation, as well as acetyl group hydrolysis on the molecular chain of hemicellulose. These changes collectively impacted the physical and mechanical properties of bamboo. [ABSTRACT FROM AUTHOR]

In this study, the effect of chickpea dietary fiber (CDF) concentration (0%, 0.4%, 0.8%, 1.2%, 1.6%, and 2.0%) on emulsion gel properties of myofibrillar protein (MP) was investigated. It was found that the emulsifying activity index (EAI) and emulsifying stability index (ESI) of MP increased with the increasing content of CDF. Moreover, the water- and fat-binding capacity (WFB), gel strength, storage modulus (G'), and loss modulus (G") of MP emulsion gel also increased with increasing content of CDF. When the concentration of CDF was 2%, the most significant improvement was observed for EAI, breaking force, and WFB (p < 0.05); the three-dimensional gel network structure of the MP emulsion gel was denser and the pore diameter was smaller. The T21 relaxation time of emulsion gel decreased while the PT21 increased significantly with the increasing content of CDF, suggesting that the emulsion gel with CDF had a better three-dimension network. The addition of CDF led to an increased content of β-sheet and reactive sulfhydryl and increased surface hydrophobicity of MP, thus improving the gel properties of the MP emulsion gel. In conclusion, the addition of CDF improved the functional properties and facilitated the gelation of the MP emulsion, indicating that CDF has the potential to improve the quality of emulsified meat products. [ABSTRACT FROM AUTHOR]

Nowadays, corporations constantly innovate to stay ahead of the competition in the contemporary business environment. Thus, enterprises invest in high-performance work systems (HPWS) that foster employee growth and improve their abilities, in turn, to accomplish digital innovation in the circular economy. The primary objective of this study is to better understand how high-performance work systems (HPWS) and digital innovation interact, while also examining the potential mediating roles of e-learning and the moderating effects of a supportive organisational culture between them. For data collection, a questionnaire and quantitative method was used, and the survey included a sample of 575 workers from the tourism sector of China. According to the findings, HPWS is favourably correlated with digital innovation, and e-learning serves as a partial intermediary in this relationship. The outcomes also demonstrate that an encouraging organisational culture further strengthens the connection between HPWS and digital innovation. These findings emphasized the value of introducing HPWS and e-learning initiatives in organisations to promote digital innovation while also highlighting the necessity of a supportive culture to maximize the advantages of these projects. [ABSTRACT FROM AUTHOR]

Conjugated small molecules bearing the cyano group were reviewed. These organic compounds are extensively used as active layers of solar cells and light-emitting diodes as well as materials with high second- and third-order nonlinearities. Typical organic light conversion agents are also based on CN-capped π-conjugated scaffolds that, in addition, are also increasingly popular for building various organic sensors and probes. More recently, cyanoarenes and dicyanopyrazines were identified as efficient photoredox catalysts. Fundamental structure–property relationships of CN-capped molecules used across the aforementioned areas were elucidated and discussed. The cyano group possessing electron-withdrawing character and linear arrangement is capable of significantly altering electronic and optical properties, and supramolecular arrangement. Hence, extensive property tuning/regulation through the CN group has been demonstrated. [ABSTRACT FROM AUTHOR]

The composition/content of aroma compounds in tobacco leaves in the different producing areas varies too much, and it is very meaningful to develop advanced analysis techniques to investigate the composition/content-producing area correlation. Here, gas chromatography-ion mobility spectroscopy (GC-IMS) was used to analyze the composition/content of aroma compounds in tobacco samples from eight different producing areas. With this technique, ion mobility spectrum, differential ion mobility spectrum, and fingerprint spectrum were constructed for two-dimensional analysis. Then, the principal component analysis (PCA) and similarity analysis were performed for the eight tobacco samples. The results showed that the GC-IMS can detect 197 volatile aroma compounds in tobacco leaves and 75 of them are well identified. The fingerprint spectrum directly showed the difference in the composition/content of volatile aroma compounds in tobacco leaves from different producing areas. PCA and similarity analysis can clearly distinguish tobacco samples from different producing areas. This work demonstrated that the application of GC-IMS in analyzing the composition/content of aroma compounds in tobacco leaves is efficient. GC-IMS is a very powerful tool to give a direct and visual comparison of the composition/content of aroma compounds in tobacco leaves from different producing areas. The relationship between the composition/content of aroma compounds and producing areas could be established by this advanced technology. This work offers the possibility of planting or grading tobacco with different taste and smell more precisely in the future. [ABSTRACT FROM AUTHOR]

Fixation nitrogen using renewable energy has attracted much attention recently. However, the performance is limited by the competing hydrogen evolution reaction (HER) and the difficulty in activating N2. Here, an attractive strategy was proposed to enhance the electrochemical nitrogen reduction reaction (NRR) activity by introducing Pd into the HKUST‐1 framework. After thermal treatment, the obtained Pd/HKUST‐1 (250 °C) catalyst exhibited an ammonia production rate of 42.0 mg/gcat ⋅ h at −0.4 V vs. RHE with Faradaic efficiency of 4.6 %. The ammonia production reached as high as 415 mg/gcat in a 10‐hours stability test. With the assistance of density functional theory (DFT) calculations, the incorporated Pd was revealed to have the unique property to react with adsorbed H (Had) atom from HER and form α‐PdH species. Compared with other metals such as Ag, Au, and Pt, the in situ formed α‐PdH species could reduce the energy barrier of the rate‐limiting *N2H step, resulting in an enhanced NRR activity. [ABSTRACT FROM AUTHOR]

Polycaprolactone (PCL) is one of the promising linear aliphatic polyesters which can be used as mulching film. Although it has suitable glass transition temperature and good biodegradability, further practical applications are restricted by the limited temperature-increasing and moisturizing properties. The rational design of the PCL structure is a good strategy to enhance the related properties. In this study, thermally-induced phase separation (TIPS) was introduced to fabricate a PCL nanoporous thin film. The introduction of a nanoporous structure on the PCL surface (np-PCL) exhibited enhanced temperature-increasing and moisturizing properties when used as mulch film. In detail, the average soil temperature of np-PCL was increased to 17.81 °C, when compared with common PCL of 17.42 °C and PBAT of 17.50 °C, and approaches to PE of 18.02 °C. In terms of water vapor transmission rate, the value for np-PCL is 637 gm−2day−1, which was much less than the common PCL of 786 and PBAT of 890 gm−2day−1. As a result, the weed biomass under the np-PCL was suppressed to be 0.35 kg m−2, almost half of the common PCL and PBAT. In addition, the np-PCL shows good thermal stability with an onset decomposition temperature of 295 °C. The degradation mechanism and rate of the np-PCL in different pH environments were also studied to explore the influence of nanoporous structure. This work highlights the importance of the nanoporous structure in PCL to enhance the temperature-increasing and moisturizing properties of PCL-based biodegradable mulching film. [ABSTRACT FROM AUTHOR]

This study aimed to develop an effective technique for extracting total anthocyanins from purple sweet potato (Mianzishu 9) (PSP9) by ultrasound-assisted compound enzymatic extraction (UAEE). Single-factor experiments, Plackett-Burman experimental design, and response surface methodology were utilized for optimizing extraction conditions, and the antioxidant activities were evaluated. Anthocyanins were also measured using an ultra-performance liquid chromatograph linked to a mass spectrometer (UPLC-MS). The maximum yield of total anthocyanins was 2.27 mg/g under the following conditions: the ethanol concentration was 78%, the material-to-liquid ratio was 1:15 g/mL, the enzyme ratio (cellulase: pectinase: papain) was 2:2:1 and its hydrolysis was at 41 °C, pH = 4.5, 1.5 h, the ultrasonication was at 48 °C and conducted twice for 20 min each time. In addition to higher yield, anthocyanins extracted from purple sweet potato by UAEE showed great ability to scavenge DPPH (IC50 of 0.089 μg/mL) and hydroxyl radicals (IC50 of 100.229 μg/mL). Five anthocyanins were found in the purple sweet potato extract from UAEE. Taken together, the ultrasound-assisted compound enzymatic method can rapidly and effectively extract anthocyanins with greater antioxidant capacity from purple sweet potato. [ABSTRACT FROM AUTHOR]

The optimization effect of evaporative cooling ventilation cooling system for air compressor room in textile mills were studied. For on-site test of the air compressor room in one textile mill, the standard k-e model in RANS method of numerical simulation was used to simulate the air distribution of air compressor room.Reginal cooling optimization design was performed for the air compressor device. And the effect was compared. The test results showed that the average temperature around 1 m front and back of the device was decreased obviously.The unevenness coefficient of the temperature was decreased from 0.157 6 to 0.112 0. It is considered that the optimization scheme can obviously reduce the surface temperature of the air compressor. The indoor temperature evenness is improved too.It has better cooling effect. [ABSTRACT FROM AUTHOR]

Clustering, a traditional machine learning method, plays a significant role in data analysis. Most clustering algorithms depend on a predetermined exact number of clusters, whereas, in practice, clusters are usually unpredictable. Although the Elbow method is one of the most commonly used methods to discriminate the optimal cluster number, the discriminant of the number of clusters depends on the manual identification of the elbow points on the visualization curve. Thus, experienced analysts cannot clearly identify the elbow point from the plotted curve when the plotted curve is fairly smooth. To solve this problem, a new elbow point discriminant method is proposed to yield a statistical metric that estimates an optimal cluster number when clustering on a dataset. First, the average degree of distortion obtained by the Elbow method is normalized to the range of 0 to 10. Second, the normalized results are used to calculate the cosine of intersection angles between elbow points. Third, this calculated cosine of intersection angles and the arccosine theorem are used to compute the intersection angles between elbow points. Finally, the index of the above-computed minimal intersection angles between elbow points is used as the estimated potential optimal cluster number. The experimental results based on simulated datasets and a well-known public dataset (Iris Dataset) demonstrated that the estimated optimal cluster number obtained by our newly proposed method is better than the widely used Silhouette method. [ABSTRACT FROM AUTHOR]

In-memory big data computing, widely used in hot areas such as deep learning and artificial intelligence, can meet the demands of ultra-low latency service and real-time data analysis. However, existing in-memory computing frameworks usually use memory in an aggressive way. Memory space is quickly exhausted and leads to great performance degradation or even task failure. On the other hand, the increasing volumes of raw data and intermediate data introduce huge memory demands, which further deteriorate the short of memory. To release the pressure on memory, those in-memory frameworks provide various storage schemes options for caching data, which determines where and how data is cached. But their storage scheme selection mechanisms are simple and insufficient, always manually set by users. Besides, those coarse-grained data storage mechanisms cannot satisfy memory access patterns of each computing unit which works on only part of the data. In this paper, we proposed a novel task-aware fine-grained storage scheme auto-selection mechanism. It automatically determines the storage scheme for caching each data block, which is the smallest unit during computing. The caching decision is made by considering the future tasks, real-time resource utilization, and storage costs, including block creation costs, I/O costs, and serialization costs under each storage scenario. The experiments show that our proposed mechanism, compared with the default storage setting, can offer great performance improvement, especially in memory-constrained circumstances it can be as much as 78%. [ABSTRACT FROM AUTHOR]

Two novel nonlinear optical (NLO) chromophores JC-T-TCF and JC-F-TCF utilizing tetramethyljulolidine-based coumarin and tricyanofuran(TCF) as the electron donor and acceptor, respectively, were designed and synthesized. The two chromophores were linked with different π conjugated electron bridge (thiophene group and furan group), which provide the opportunity to study the structure–property relationship of coumarin-based chromophores. Both the novel obtained chromophores exhibited reasonable stability and solvatochromic effect. The theoretical calculation results indicated that both chromophores possess microscopic hyperpolarizability (β) in excess of 320 × 10−30esu, and the chromophore JC-T-TCF utilizing thiophene group as the electron bridge exhibited obviously larger β value (456.8 × 10−30esu). The larger β value, combination with the larger µ value, endowed JC-T-TCF with larger electro-optic activity of 70 pm V−1 at the wavelength of 1310 nm in the guest–host films of chromophores doped into PMMA, which provide the potential application opportunity in the field of optical waveguide devices. [ABSTRACT FROM AUTHOR]

As greater numbers of data-intensive applications are required to process big data in bandwidth-constrained datacenters with heterogeneous physical machines (PMs) and virtual machines (VMs), network core traffic is experiencing rapid growth. The VMs of a virtual cluster (VC) must be allocated as compactly as possible to avoid bandwidth-related bottlenecks. Since each PM/switch has a certain failure probability, a VC may not be executed when it meets with any PM/switch fault. Although the VMs of a VC can be spread out across different fault domains to minimize the risk of violating the availability requirement of the VC, this increases the network core traffic. Therefore, avoiding the decrease in availability caused by the heterogeneous PM/switch failure probabilities and bandwidth-related bottlenecks has been a constant challenge. In this paper, we first introduce a joint optimization function to measure the overall risk cost and overall bandwidth usage in the network core to allocate the same set of data-intensive applications. We then introduce an approach to maximize the value of the joint optimization function. Finally, we performed a side-by-side comparison with prior algorithms, and the experimental results show that our approach outperforms the other existing algorithms. [ABSTRACT FROM AUTHOR]

Featured Application: Solanesol molecularly imprinted polymers (SSO-MIPs) can specifically recognize solanesol to achieve the purpose of improving the purity of solanesol. The obtained high-purity solanesol can be used in pharmaceuticals, such as anti-cancer and anti-ulcer drugs, etc. High-purity solanesol can be used for pharmaceutical applications, but the current method for purifying solanesol has high cost and difficult continuous operation, and the use of molecular imprinting to purify natural products is a hot research topic of current research. Solanesol molecularly imprinted polymers were synthesized via emulsion polymerization for the first time. The morphology of the SSO-MIPs was observed with a scanning electron microscope, and the effects of the synthesis time, initiator dosage, functional monomer dosage, and cross-linking agent dosage on the adsorption effects under high-temperature and rapid synthesis conditions were discussed. The results demonstrate that the optimum synthesis conditions were a ratio of the template molecules to the functional monomers to the cross-linking agents of 1:8:30 (mol:mol:mol), 10 mg of the initiator, and a synthesis temperature of 70 °C. The imprinting factor of SSO-MIPs synthesized under the optimized process was found to reach 2.51, and the SSO-MIPs synthesized by this method exhibited a good adsorption effect, emitted less pollution during the synthesis process, and are convenient for demulsification. This research reports a reliable method for the synthesis of solanesol molecularly imprinted polymers. [ABSTRACT FROM AUTHOR]

Since service level agreement (SLA) is essentially used to maintain reliable quality of service between cloud providers and clients in cloud environment, there has been a growing effort in reducing power consumption while complying with the SLA by maximizing physical machine (PM)-level utilization and load balancing techniques in infrastructure as a service. However, with the recent introduction of container as a service by cloud providers, containers are increasingly popular and will become the major deployment model in the cloud environment and specifically in platform as a service. Therefore, reducing power consumption while complying with the SLA at virtual machine (VM)-level becomes essential. In this context, we exploit a container consolidation scheme with usage prediction to achieve the above objectives. To obtain a reliable characterization of overutilized and underutilized PMs, our scheme jointly exploits the current and predicted CPU utilization based on local history of the considered PMs in the process of the container consolidation. We demonstrate our solution through simulations on real workloads. The experimental results show that the container consolidation scheme with usage prediction reduces the power consumption, number of container migrations, and average number of active VMs while complying with the SLA. [ABSTRACT FROM AUTHOR]

Developing new organic chromophores with a large electro-optic coefficient (r33) is highly desirable for fabricating electro-optic (EO) materials. Building on the fact that the 1,1,7,7-tetramethyl julolidine fused furan ring is a good electron donor and lengthening the π-bridge of a chromophore with a five-membered heterocycle ring could lead to the improvement of r33. Here we design and synthesize two new chromophores C1 and C2 by using a 1,1,7,7-tetramethyl julolidine fused furan ring as the electron donor and 2-(3-cyano-4,5,5-trimethyl-5H-furan-2-ylidene)-malonitrile (TCF) as the acceptor, but with two different π-bridges (furan-vinylene and thiophene-vinylene accordingly). When doping C1 or C2 into PMMA with a loading density of 20 wt%, the poled films containing C1 or C2 exhibited an r33 value of 75 pm V−1 and 94 pm V−1, respectively. When compared with chromophore C3 (an ene unit as the π-bridge, r33 = 52 pm V−1), an enhanced r33 of C1 and C2 was achieved due to the introduction of a heterocycle ring into the π-bridge. This work uncovers the influence of the heterocycle ring on the julolidine fused furan based chromophore's physical and chemical properties and demonstrates that the new chromophores are a promising candidate for EO material application. [ABSTRACT FROM AUTHOR]

Two principally novel chromophores A, B based on fluorene electron donor were synthesized and explored by 1H NMR, 13C NMR, and MS spectra. The delocalized energy levels have been estimated by UV–Vis absorption spectra. The principal innovation consists in modification by addition of amino group. The titled materials have demonstrated a high solubility in common organic solvents, good compatibility with polymers. The maximally achieved electro-optic efficiency of the poled film possessing 25 wt% of A doped in PMMA (25 wt% A/PMMA) achieved a value of 18 pm/V at wavelength 1310 nm, and 25 wt% B/PMMA possessed an electrooptical coefficient equal to 43 pm/V. This one open a perspective of their direct application in optoelectronic telecommunication devices for laser light modulation. [ABSTRACT FROM AUTHOR]

Cloud data center traffic is experiencing a rapid growth as more and more data-intensive applications are required to process big data in a cloud data center. Although fat-tree networks own rich path multiplicity, and have been widely adopted as network topologies in cloud data center networks to transmit vast bisection bandwidth, they lead to bandwidth-related bottlenecks. To address this issue, in this paper, we propose a traffic-aware virtual cluster reallocation approach via biogeography-based optimization to allocate some reallocated virtual machines (VMs) as compact as possible with those VMs in the same virtual clusters. In order to validate our approach, we build a system model to perform a thorough evaluation of its performance. Experimental results show that our proposed approach outperforms six existed approaches in term of total transmission cost, total processing time, and total network resource consumption. [ABSTRACT FROM AUTHOR]

Organic nonlinear optical materials have been widely explored because of their advantages in the design of materials with large electro-optic coefficients used in the fabrication of novel optoelectronic and telecommunication devices. However, the huge dipole-dipole interactions between organic nonlinear optical chromophores have limited further improvements in the electro-optic coefficients and long-term material stability. Here, a novel polymer based on poly(aryl ether ketone) was designed and prepared to enhance the electro-optic coefficients and achieve higher long-term stability. This novel poly(aryl ether ketone) has a relatively high glass transition temperature and offers active functional groups for the attachment of organic nonlinear optical chromophores. After attachment of nonlinear optical chromophores the materials showed higher chromophore loading density, less inter-molecular interaction, and suitable solubility. This resulted in better film-forming ability, higher electro-optics coefficients and better long-term stability. Quantum chemical simulations of the second order hyperpolarizabilities and ground sate dipole moments were done to understand the origin of the effects. [ABSTRACT FROM AUTHOR]

Principally novel crosslinking nonlinear optical and optoelectronics system based on Diels-Alder reaction was designed. The copolymer of methyl methacrylate and anthracen-9-ylmethyl methacrylate (PMMA-AMA) was used as a host polymer; chromophore ETO was used as guest chromophore; chromophore ETO and N,N-(methylenediphenyl)bismaleimide were used as crosslinker. The thermodynamic property of crosslinking system studied by differential scanning calorimeter (DSC) showed us that the glass transition temperature was about 65 °C and the crosslinking temperature was varied between 80 and 120 °C The crosslinking reactive speed and effectiveness were studied by ultraviolet absorption and infrared absorption spectroscopy with spectral resoluiotn 1 cm. These results have indicated that the cross linking process could be finished at 110 °C for 20 min. Surprisingly, such EO polymer showed us a large EO coefficient of about 96.3 pm/V at wavelength 1 µm and excellent long term stability about 85% with respect to its initial value and can be kept after 250 h of heating at 80 °C. [ABSTRACT FROM AUTHOR]

A series of chromophores J1–J4 have been synthesized based on julolidine donors modified with different rigid steric hindrance groups. Compared with the chromophore (J1) without the isolation group, chromophores J2, J3 and J4 show better stability. Structural analysis and photophysical property measurements were carried out to compare the molecular mobility and steric hindrance effect of the different donor-modified chromophores. All of these chromophores with isolation groups showed superb thermal stabilities with high thermal decomposition temperatures above 250 °C. Furthermore, with rigid steric hindrance, chromophores J3 and J4 showed more enhanced thermal stabilities with thermal decomposition temperatures of 269 °C and 275 °C, respectively. Density functional theory was used to calculate the hyperpolarizability (β), and the high molecular hyperpolarizability of these chromophores can be effectively translated into large electro-optic coefficients. The electro-optic coefficients of poled films containing 20 wt% of these new chromophores doped in amorphous polycarbonate were 127, 266 and 209 pm V−1 at 1310 nm for chromophores J1–J3, respectively, while the film containing chromophore J4 showed the largest r33 value of only 97 pm V−1 at 25 wt%. These results indicated that the introduced isolation group can reduce intermolecular electrostatic interactions, thus enhancing the macroscopic electro-optic activity, while the size of the isolation group should be suitable. [ABSTRACT FROM AUTHOR]

Due to the simple preparation technology and appropriate crosslinking process, polyurethane was selected as the host polymer for the preparation of organic electro-optics (EO) materials. The synthesis and crosslinking process of polyurethane demanded the nonlinear optical (NLO) chromophore possessing strong stability in acid environment. Fortunately, after the introduction of azo group in the electronic bridge, the stability of this kind of chromophores in acidic environment was improved greatly. Polyurethane EO polymers and EO films based on this kind of chromophore were prepared successfully. The crosslinking process was monitored by infrared spectroscopy clearly. The crosslinking process has direct relationship with the molecular weight of the crosslinkers. Crosslinker of triethanolamine with small molecular weight showed low crosslinking temperature (80 °C) and short crosslinking time (20 min). The crosslinking temperature and time was improved to 140 °C and 60 min based on Poly(bisphenol A glycidyl ether aniline) (BPAN) crosslinker with large molecular weight. More importantly, this kind of EO polymers showed us large second order nonlinear optical coefficients (76.1 pm/V) and good long term stability (130 °C). [ABSTRACT FROM AUTHOR]

Three novel second order nonlinear optical (NLO) chromophores based on julolidinyl donors and tricyanofuran (TCF) acceptors linked together via modified polyene π-conjugation with rigid benzene derivative steric hindrance groups (chromophore CL1 and CL2) or unmodified polyene π-conjugation (chromophores CL) moieties as the bridges have been synthesized in good overall yields and systematically characterized. Density functional theory (DFT) was used to calculate the HOMO–LUMO energy gaps and first-order hyperpolarizability (β) of these chromophores. Besides, to determine the redox properties of these chromophores, cyclic voltammetry (CV) experiments were performed. Compared with CL, after introducing benzene derivative steric hindrance groups into the bridge, chromophores CL1 and CL2 had good thermal stabilities with high thermal decomposition temperatures which were 32 °C and 24 °C higher than chromophore CL, respectively. Most importantly, the introduction of rigid steric hindrance groups can effectively reduce dipole–dipole interactions to translate their relatively small β values into bulk high EO activities. By doping chromophores CL, CL1 and CL2 with a high loading of 45 wt% in APC, EO coefficients (r33) of up to 121, 197 and 202 pm V−1 at 1310 nm can be achieved, respectively. The r33 values of new chromophores CL1 and CL2 were about 1.6 times of chromophore CL. The high r33 value, good thermal stability and high yield suggest the potential use of the new chromophores in an nonlinear optical area. [ABSTRACT FROM AUTHOR]

A series of Y-shaped chromophores A1, A2, B1 and B2 based on the same thiophene π-conjugation and tricyanofuran acceptor (TCF) but with different donors (modified phenothiazine and triphenylamine) have been synthesized and systematically investigated in this paper. Density functional theory (DFT) was used to calculate the HOMO–LUMO energy gaps and first-order hyperpolarizability (β) of these chromophores. These chromophores showed excellent thermal stability with their decomposition temperatures all above 270 °C. Most importantly, the high molecular hyperpolarizability of these chromophores can be effectively translated into large electro-optic (EO) coefficients (r33) in poled polymers. The doped film-C containing 25 wt% chromophore B1 displayed an r33 value of 72 pm V−1 at 1310 nm, and the doped film-D containing B2 showed a value of 95 pm V−1 at a concentration of 25 wt%. These values are all much higher than the traditional FTC chromophore (39 pm V−1). High r33 values indicated that the special Y structure can reduce intermolecular electrostatic interactions and thus enhance the macroscopic EO activity. These properties, together with the good solubility, suggest the potential use of these new chromophores as materials for advanced devices. [ABSTRACT FROM AUTHOR]

A series of chromophores FTC, L1 and L2 have been synthesized based on three different types of electron donors, including diethylaminophenyl, tetrahydroquinolinyl and N-(4-dimethylaminophenyl) tetrahydroquinolinyl groups respectively, with the same thiophene bridges and strong tricyanovinyldihydrofuran (TCF) acceptors. In particular, the donor part of the chromophore L2 was modified with an additional donor N-(4-dimethylaminophenyl) substituent, resulting in enhanced thermal stability and electro-optic activity. Cyclic voltammetry measurements showed that chromophore L2 had a smaller energy gap than chromophore L1 due to the additional donor. Moreover, density functional theory calculations suggested that the molecular quadratic hyperpolarizability (μβ) value of chromophore L2 is 29% and 44% larger than that of chromophores L1 and FTC, respectively. The doped film containing the chromophore L2 showed an r33 value of 100 pm V−1 at the concentration of 25 wt% which is much higher than the EO activity of the chromophore L1 (57 pm V−1) and two times higher than that of the traditional chromophore FTC (39 pm V−1). [ABSTRACT FROM AUTHOR]

A series of chromophores T1–T3 based on the same thiophene π-conjugation and tricyanofuran acceptor (TCF) but with different heteroatoms in the triarylaminophenyl (TAA) donors have been synthesized and systematically investigated in this study. Density functional theory (DFT) was used to calculate the HOMO–LUMO energy gaps and first-order hyperpolarizability (β) of these chromophores. Moreover, to determine the redox properties of these chromophores, cyclic voltammetry (CV) experiments were performed. After introducing the heteroatom to the benzene ring of the TAA donor, reduced energy gaps of 1.28 and 0.84 eV were obtained for chromophores T2 and T3, respectively, which was much lower than for chromophore T1 (ΔE = 1.46 eV). These chromophores showed excellent thermal stability with their decomposition temperatures all above 280 °C. Compared with results obtained from the chromophore without the heteroatom (T1), these new chromophores show better intramolecular charge-transfer (ICT) absorption. Most importantly, the high molecular hyperpolarizability (β) of these chromophores can be effectively translated into large electro-optic (EO) coefficients (r33) in the poled polymers. The electro-optic coefficient of poled films containing 25 wt% of these new chromophores doped in amorphous polycarbonate (APC) afforded values of 16, 58 and 95 pm V−1 at 1310 nm for chromophores T1–T3, respectively. High r33 values indicated that introducing heteroatom to the benzene ring of the TAA donor can efficiently improve the electron-donating ability, which improves the hyperpolarizability (β). The long-chain on the benzene ring of the TAA donor, acting as the isolation group, may reduce intermolecular electrostatic interactions, thus enhancing the macroscopic EO activity. These properties, together with the good solubility, suggest the potential use of these new chromophores as advanced material devices. [ABSTRACT FROM AUTHOR]