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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. monocytogenesdetection is of great needed. In this study, we present a simple method for L. monocytogenesdetection combined aptamers decorated magnetic beads for selective capture and gold nanoparticles (AuNPs) mediated signal amplication. A NH2labeled aptamer specific to L. monocytogeneswas decorated on magnetic beads for selective capture and isolation of L. monocytogenesfrom food sample. AuNPs was functionalized with sulfhydryl modified primers specific to hlygene of L. monocytogenesin acidic environments. The AuNP@primers could catalyze TMB-H2O2to 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. monocytogenesDNA 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 101CFU/mL of L. monocytogenes. For the detection of L. monocytogenesin 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. monocytogenesin food.

The COVID-19 pandemic has elicited interest in the development of novel, low-cost solutions for tele-healthcare that patients can use to consult with doctors using consumer electronics (CEs). Android CEs typically have multiple network interfaces. Simultaneous access to multiple interfaces can greatly enhance users’ quality of experience (QoE). To enhance data transmission throughput and robustness in tele-healthcare systems, we propose a QoE-driven data communication framework which can cater to all types of healthcare apps. The framework includes a QoE-driven congestion controller (QCC) and a QoE-driven MPTCP (multipath transmission control protocol) scheduler (QMS). Different app types correspond to specific QoE parameters that influence the QCC and QMS for meeting diverse healthcare app requirements. No server-side modifications are needed for this framework; only changes on the Android client side are necessary. We implement and experiment with the framework on an Android 13 smartphone in a real environment. Experimental results confirm the framework’s effectiveness and availability, and show that the QCC and QMS reduce completion time for transferring small files by at least 4.71% and for transferring big file by at least 13.94% compared with existing solutions.

Foodborne pathogens Listeria monocytogenes, SalmonellaTyphimurium and Escherichia coliO157: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, SalmonellaTyphimurium and Escherichia coliO157: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 × 101to 3.5 × 102CFU mL−1for 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.

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 monocytogenesantibody 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 monocytogenesin the range of 105-108CFU mL− 1, with a visual detection limit of 3.3 × 106CFU 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.

Listeria monocytogenesis one of the major foodborne pathogens, which may cause serious food safety problems and illnesses in humans and animals. Consequently, sensitive, fast and reliable detection methods, as well as effective sample preparation methods are in great demand. In this study, a magnetic separation method based on a aptamer functionalized positively-charged magnetic beads (Fe3O4@aptamer) was established and a fluorescent test strip sensor was constructed for the rapid, sensitive and specific detection of Listeria monocytogenes. Benefiting from the dual recognition and signal amplification process of Fe3O4@aptamer enrichment and the polymerase chain reaction of the hlygene, the fluorescent strip sensor for the detection of Listeria monocytogeneswas determined to be reliable and sensitive, with a linear curve obtained in the range of 1.0 × 102to 1.9 × 108CFU mL−1, and a detection limit of 1.0 × 102CFU mL−1. The detection was achieved in 3 h without culture enrichment. Furthermore, the developed method was successfully applied for the detection of Listeria monocytogenesin pork tenderloin, with the recoveries ranging from 91.1% to 97.1%, and a coefficient of variation of less than 23.4%, revealing the feasible and reliable application of this method in practical samples. The proposed fluorescent strip sensor is rapid, sensitive and specific, giving it great application prospects for use in the field of pathogenic bacterium detection.

Listeria monocytogenes(L. monocytogenes) is one of the most lethal pathogenic bacteria. Although the traditional microbial culture method has high sensitivity and selectivity for the diagnosis of L. monocytogenes, it is time-consuming and not suitable for on-site detection. A rapid, convenient and visualized on-site detection method is particularly needed. In this work, Fe3O4@UiO-66-NH2was prepared for both magnetic separation and lateral flow immunoassay (LFIA) for the detection of L. monocytogenesby taking advantage of the easy separation of the magnetic core Fe3O4and the high surface area of the outer layer UiO-66-NH2. Fe3O4@UiO-66-NH2with a high surface area and good water-dispersibility and optical properties was synthesized by a simple hydrothermal process. It could directly adsorb on the surface of target bacteria and form Fe3O4@UiO-66-NH2-bacteria conjugates, without the labeling of an antibody. After magnetic separation and concentration, the Fe3O4@UiO-66-NH2-bacteria conjugates were detected by the antibody on the test line of the LFIA strip, resulting in a visible orange band. The capture efficiency and LFIA detection of Fe3O4@UiO-66-NH2were optimized in this study. Under the optimal conditions, a good linear correlation between the test line intensity and the concentration of L. monocytogeneswas obtained in the range of 105–108CFU mL−1, and the limit of detection was 2.2 × 106CFU mL−1by the naked eye. The Fe3O4@UiO-66-NH2-based LFIA strip showed strong specificity for L. monocytogenes, and the detection took 45 min without culture enrichment. Therefore, the proposed Fe3O4@UiO-66-NH2-based strip showed the advantages of simple synthesis, being label-free, low cost, good selectivity and convenience.

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.

Solanesol has antibacterial, anticancer, anti-inflammatory and antiulcer biological activities, and is a key intermediate in the synthesis of coenzyme Q10, vitamin K2, and the anticancer synergist N-solanesyl-N,N'-bis(3,4-dimethoxy-benzyl)ethylenediamine (SDB) and other ubiquinone drugs. Due to its unique chemical structure, the chemical synthesis of solanesol is difficult, so solanesol is currently mainly isolated from solanaceous plants. Tobacco (Nicotiana tabacum) has the highest content of solanesol compared to other solanaceous plants. Currently, the research on the extraction of solanesol from tobacco focuses on its extraction and purification. This article reviews the extraction methods, saponification, separation and purification methods of solanesol, as well as the research progress on tobacco solanesol, in China and abroad in recent years. Studies show that the organic solvent extraction method is time-consuming and has a low extraction rate. Modern technology- assisted extraction methods, such as ultrasound-assisted extraction, microwave-assisted extraction, and supercritical carbon dioxide (CO2) extraction not only can improve the extraction rate but also can effectively shorten the extraction time. The separation and purification of solanesol from the extracting solution are critical steps to meet the purity requirements of synthetic drugs, and are also key in limiting the large-scale industrial production of high-purity solanesol. Molecular Imprinting Technology (MIT) has the advantages of small investment, simple operation and ease of large scale production compared to chromatographic methods. Solanesol separated by MIT can meet the requirements for synthesizing coenzyme Q10. Nowadays, the synthesis of molecularly-imprinted solanesol polymers with better adsorption efficiency is one of the important directions in the future research of solanesol purification.

AbstractMatrix metal proteinases-12 (MMP-12) is a hot pharmaceutical target on the treatment of many human diseases. There’s a crying need for designing and finding new MMP-12 inhibitors. In this work, four machine learning approaches, support vector machine, k-nearest neighbor, C4.5 decision tree, and random forest, were employed to derive statistical models from datasets with well distributed biological activities and predict a compound whether it is a MMP-12 inhibitor. The prediction accuracies of the models are in the range of 96.15–98.08% for sensitivity, 87.23–100.00% for specificity, 91.92–98.99% for the overall prediction accuracy and 0.8401–0.9800 for Matthews correlation coefficient, all producing satisfactory results. By means of diverse feature selection methods, several sets of critical descriptors with key information of inhibitory properties were selected by different models, accelerating the classification for MMP-12 inhibitors and non-inhibitors.Communicated by Ramaswamy H. Sarma

Conversion efficiency between electrical and optical signals is very important for the development of modern information technologies. Due to their advantages in half-wave voltage, bandwidth, cost and integration, as well as organic electro-optic (EO) parameters, these materials are widely studied and used in microwave photonic devices. Second order nonlinear optical (NLO) chromophores, as the core of organic EO materials have an increasing interest in this branch. Auxiliary donors present a new direction for the design and improvement of organic NLO chromophores. In this short review, the advantages, theoretical calculations and experimental results of auxiliary donors are reviewed and discussed in detail.

In this review, small-molecule donors for application in organic solar cells reported in the last three years are highlighted. Especially, the effect of donor molecular structure on power conversion efficiency of organic solar cells is reported in detail. Furthermore, the mechanism is proposed and discussed for explaining the relationship between structure and power conversion efficiency. These results and discussions draw some rules for rational donor molecular design, which is very important for further improving the power conversion efficiency of organic solar cells based on the small-molecule donor.

Main-chain nonlinear optical polymers based on novel chromophores with special structures presented good solubility in most of the organic solvents. Polymers PE-1 and PE-2 attained the thermal decomposition temperatures of 305 and 223 °C and glass transition temperatures of 113 and 108 °C, and exhibited only negligible decay in the SHG signal baked at 85 °C over hundreds of hours, respectively. The SHG coefficients of poled films from polymers PE-1 and PE-2 were 26.3 and 35.8 pm/V, respectively. These results indicated that this class of polymers can be used in the preparation of organic electro-optic devices.

Binary polymer blends that can form hydrogen-bond networks were prepared and used to fabricate the guest-host organic electro-optic (EO) materials. The hydrogen-bonds network in the solid films of novel guest-host organic EO materials was verified by FT-IR spectra. After corona poling, two kinds of EO films revealed the maximum EO coefficient value (r33) of 19.5 and 30 pm/V at the wavelength of 1310 nm. The EO activity and the order parameter of the chromophores in the poled films both indicated that the hydrogen-bond network has little impact on the motion of the chromophores while poling. These new EO films exhibited better temporal stability after 250 h at 55 and 85 °C compared with the conventional guest-host systems that have the similar or higher Tgs. Moreover, the results also indicated that polymer blends as the host of EO materials can change the dielectric strength of the materials, which directly influence the poling efficiency.

Abstract: This article reports a synthesis a new class of nonlinear optical (NLO) polymer, containing 3-methyl-4-cyano-5-dicyanomethylidene-2-oxo-3-pyrroline (TCP) acceptor. TCP chromophore was synthesized and characterized by Uv-Vis absorption, 1H NMR, and mass-spectrometry. The titled polymer shows high thermal stability and large optical nonlinearity. A high glass transition temperature of 125°C was determined by DSC measurement, and measured electrooptical (EO) at wavelength 1.31 mm was equal to 37.4 pm/V. The order parameter of these films evaluated by absorption was equal to about 24%.

Plasma nitride SiON films have been widely used as gate dielectric in advanced CMOS device fabrication since 90nm technology node. As a replacement material for conventional silicon dioxide, it can provide increased dielectric constant and serve as an effective boron barrier. Post nitridation anneal (PNA), a critical step for plasma nitride SiON formation, is used to stabilize plasma incorporated nitrogen radicals and ions through form thermal stable Si-N banding. Furthermore, PNA can repair the damaged Si/SiO2 interface by interface substrate re-oxidation under oxygen contained ambient. In this work, several PNA conditions were studied. Their effect on transistor performance and PMOS NBTI (Negative Bias Temperature Instability) lifetime were evaluated. It demonstrates that NBTI performance can be improved 20% by PNA process optimizing, while keeping the same Tinv thickness and Ioff/Ion performance.

Abstract: The paper describes the growth of a germanium (Ge) film on a thin relaxed Ge-rich SiGe buffer. The thin Ge-rich SiGe buffer layer was achieved through a combination of ultrahigh vacuum chemical vapor deposition (UHVCVD) SiGe epitaxial growth and SiGe oxidation. A lower Ge content strained SiGe layer was first grown on the Si (001) substrate and then the Ge mole fraction was increased by oxidation. After removal of the surface oxide, a higher Ge content SiGe layer was grown and oxidized again. The Ge mole fraction was increased to 0.8 in the 50 nm thick SiGe layer. Finally a 150 nm thick pure Ge film was grown on the SiGe buffer layer using the UHVCVD system. This technique produces a much thinner buffer than the conventional compositionally graded relaxed SiGe method with the same order of magnitude threading dislocation density. [Copyright &y& Elsevier]

Energy, information, and materials are the three main factors required for the survival and development of modern humankind, with energy being the cornerstone of all development. In recent years, self-powered devices have received widespread attention. As a new generation device, Triboelectric nanogenerators (TENGs) assembled from flexible materials possess the characteristics of flexible design, low-cost, stable output performance, etc., and can be widely used in wearable and self-powered medical detection sensors of human body. In this paper, flexible bromobutyl rubber (BIIR) and PET were used as friction materials, and assembled into arched vertical contact-separation triboelectric nanogenerators following various film formation and surface roughening treatments. The treatment and assembly methods of the friction materials were studied in order to obtain the best power generating effects. In addition, due to the biocompatibility and intrinsic antibacterial property of BIIR films, the fabricated triboelectric nanogenerator was also applied to wearable self-powered sensor equipment, proving its potential in the fields of identification and gait analysis.

An iatrogenic pseudoaneurysm of the radial artery and spontaneous venous malformation are associated with median nerve compression. However, the superficial brachial artery (SBA) has rarely been described as the cause of neurological deficits due to median nerve compression. A 61-year-old man was admitted to our clinic with a 1-year history of intermittent aching palsy in the left thumb that had progressed to the first three fingers. Clinical examination revealed mild sensory disturbance and hyperpathia in the first three fingers and weakness of the opponens pollicis. Ultrasound and magnetic resonance imaging confirmed that the SBA was compressing the median nerve by almost one-third. When anomalies of the SBA impinge on the median nerve, pulsatile pressure is applied to the nerve trunk. This may trigger ectopic stimulation of sensory fibers, leading to severe pain, sensory neuropathy, and motor disturbance. Considering the substantial difficulties and risks of a surgical operation as well as the patient’s wish to undergo conservative treatment, we performed muscle relaxation and acupuncture to relieve the pressure of the surrounding soft tissue and in turn decrease the impingement of the SBA on the median nerve. A satisfactory treatment effect was reached in this case.

Near‐infrared (NIR) light‐responsive nanoparticles (NPs) of organic photosensitizers (PS) hold great promise as phototherapeutic agents for precision photoinduced cancer therapy. However, highly photostable PS nanoparticles with extraordinary photoconversion capacities are urgently desired to fully realize potent phototherapy. Here, NIR nonlinear organic chromophore nanoparticles (NOC‐NPs) are shown as single‐component PS for dually cooperative phototherapy. Upon 785 nm irradiation, excited NOC‐NPs pass through intrinsic intramolecular charge transfer (ICT) channel to generate both abundant singlet oxygen and local hyperthermia, affording synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) for tumor ablation. Furthermore, NOC‐NPs exhibit dramatic photostability, enhanced cellular uptake, effective cytoplasmic translocation, as well as preferable tumor accumulation, further ensuring favorable in vivo singlet oxygen generation and hyperthermia for photoinduced tumor ablation. Thus, NOC‐NPs may represent novel high‐performance PS for synergistic photoinduced cancer therapy, providing new insights into the development of potent PS for clinical translation. Ultrastable near‐infrared (NIR) nonlinear organic chromophore nanoparticles are deliberately fabricated for dually cooperative phototherapy via intrinsic intramolecular charge transfer channel, achieving tumor photoablation surgery upon NIR light exposure. This strategy provides a new avenue for the development of potent photosensitizers (PS) for phototherapeutic applications.

For 20/16nm HK-last and MG-last process, Dummy poly is removed by Wet process. This paper studies the factors impacting the dummy poly removal process, and presents some models to explain the impacting factors. Implant process is one of main factors influencing dummy poly removal capability because the differences of implant ions and doping amount into dummy poly induce difference of poly removal rate by wet process. We also study poly surface single clean, multiple clean and thermal process. Based on the model, we plan N-type doping poly and P-type doping poly with different ion doping amounts on blank wafer and 20nm structure wafers to evaluate dummy poly removal. We find dummy poly removal rate is different between N-type doping poly and P-type doping poly, and receive different dummy poly removal trend by ion amount on N-type doping poly and P-type doping poly. The model can help to improve dummy poly removal process control.

Interfacial oxide (IL) /high-k (HK) gate dielectric stack is widely used in 45nm logic technology and beyond nodes. Interfacial oxide, which is buffer layer between silicon substrate and HK dielectric, is a crucial factor to control Silicon/IL, IL/high-k interface charge and high-k film quality. In this work, atom layer deposition (ALD) Hf based HK film is deposited on two classes of IL by thermal oxidation (process A or B) and chemical oxidation (process C or D), respectively. XPS is used to characterize the film bonding energy, while non contact CV and spectroscopic ellipsometry (SE) are used to characterize the interface trap. The electric properties of the film stacks are characterized by C-V and I-V curves. The results reveal that interface trap of chemical oxide film has positive surface voltage and less dense SiOx, as compared with that of thermal oxide. With the same interfacial oxide thickness and HK deposition process, the chemical oxide/HK stack got 3.4A thick EOT, which is about two orders lower leakage than that of thermal oxide/HfO2. It can be explained by the fact that chemical oxide had plenty of O-H bonds, which is good for ALD Hf based HK film nucleation and growth and resulted in good film quality. However, due to the high Si/chemical oxide interfacial charge, the chemical oxide/HfO2dielectric stack has a disadvantage of the larger C-V hysteresis.

Plasma nitride SiON films have been widely used as gate dielectric in advanced CMOS device fabrication since 90nm technology node. As a replacement material for conventional silicon dioxide, it can provide increased dielectric constant and serve as an effective boron barrier. Post nitridation anneal (PNA), a critical step for plasma nitride SiON formation, is used to stabilize plasma incorporated nitrogen radicals and ions through form thermal stable Si-N banding. Furthermore, PNA can repair the damaged Si/SiO2 interface by interface substrate re-oxidation under oxygen contained ambient. In this work, several PNA conditions were studied. Their effect on transistor performance and PMOS NBTI (Negative Bias Temperature Instability) lifetime were evaluated. It demonstrates that NBTI performance can be improved 20% by PNA process optimizing, while keeping the same Tinv thickness and Ioff/Ion performance.