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In this paper, we have demonstrated high performance back-gated MoS 2 MOSFETs with scandium (Sc) contact and high-k ZrO 2 dielectrics for improved contact resistance and electron mobility. Record drain current of 200 µA/µm has been achieved for 1-µm channel length multilayer MoS 2 MOSFETs on ZrO 2 /Si substrates. The intrinsic contact resistance of low work function metal Sc on exfoliated MoS 2 with strong gating effect on source region is significantly decreased to 0.9 kΩ·µm. By taking the impact of contact resistance into consideration, the intrinsic mobility extracted from Y function technique is 132 cm2/Vs, 3 times higher than SiO 2 substrate, originating from the significant screening effect of high-k ZrO 2 dielectrics on the impurity scattering.

Background: Excessive scarring of filtering blebs is the main cause of surgical failure in glaucoma. Previous studies have highlighted the role of chloride channels (ClCs) in scar formation, whereas the role of ClCs in scarring of filtering blebs has not been studied. Objectives: The objective of this study was to investigate the effects of the chloride channel 2 (ClC-2) on scar formation of filtering blebs after glaucoma filtering surgery. Methods: ClC-2 siRNA-transfected human conjunctival fibroblasts (HConFs) were cultured in type 1 collagen gels in the presence of transforming growth factor (TGF)-β1. Collagen gel contraction was evaluated based on the gel area. 3D-cultured HConFs were treated with the ClC blocker NPPB in the presence of TGF-β1, and cell proliferation collagen synthesis and contractility were measured. The expression levels of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in HConFs were assessed by Western blotting and qPCR. Results: TGF-β1 induced cell proliferation, cell cycle progression, collagen synthesis, and collagen gel contraction in HConFs. TGF-β1 increased MMP-2 and MMP-9 levels but inhibited the expression of TIMPs. NPPB and ClC-2 siRNA transfection inhibited TGF-β2-induced cell proliferation, cell cycle progression, collagen synthesis, and collagen gel contraction, mediated by HConFs. TGF-β2-induced increases in MMP-2 and MMP-9 were also inhibited by NPPB and ClC-2 siRNA transfection, but TIMP expression was increased by NPPB and ClC-2 siRNA transfection. Conclusions: These findings demonstrate that ClC-2 ClCs modulate TGF-β1-induced cell proliferation, collagen synthesis, and collagen gel contraction of HConFs by attenuating MMP-2 and MMP-9 production and by stimulating TIMP1 production. NPPB may therefore prove to be of clinical value for the inhibition of scar formation of filtering blebs.

Atherosclerosis (AS) is a chronic inflammatory disease that results from Oxidized low-density lipoprotein (Ox-LDL) induced endothelial dysfunction. Cytoplasmic polyadenylation element binding protein 1 (CPEB1) is closely related to the development of epithelial cells, but the role of CPEB1 in AS remains unknown. The RNA and protein levels of CPEB1 expression are increased by Ox-LDL exposure, which is abrogated by c-Jun amino-terminal kinase (JNK) inhibitor SP600125. CPEB1 small interfering RNA (siRNA) suppressed the oxidative stress, inflammation, and apoptosis. Furthermore, CPEB1 siRNA enhanced the sirtuin 1 (SIRT1) transcription levels in Ox-LDL-treated HUVECs. Co-Immunoprecipitation (Co-IP) assay showed that CPEB1 siRNA declined the ubiquitination of SIRT1, and SIRT1 siRNA enhanced the Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), which were decreased by CPEB1 siRNA. In addition, LOX-1 and SIRT1 attenuated the protection of SIRT1 siRNA on Ox-LDL-induced oxidative stress. Therefore, our study revealed that CPEB1 depletion might play an anti-inflammatory and antiapoptotic role in Ox-LDL-induced apoptosis and inflammation though SIRT1/LOX-1 signalling pathway.

Currently most of cyber-physical-human systems are built on the cloud centric architecture, which can not support delay-sensitive applications so well. With the development of edge computing, it is possible to construct time-critical cyber-physical-human systems based on edge platforms which can process users requests locally and provide low-latency interaction for users effectively. In this paper, we present our work on designing and implementing an edge platform, named WiPi. To verify its effectiveness in building time-critical cyber-physical-human systems, we use WiPi in building a system for human-in-the-loop control of an Unmanned Surface Vehicle (USV) for online water quality monitoring. Experimental results show that the edge-enabled system can reduce the interaction delay between the device and the user by 54% at least, as compared with the cloud-centric system.

Quality of experience (QoE) is crucial for wireless network operators with respect to both technical evolution and profit promotion. However, operators are still unable to monitor user QoE effectively because traditional network quality indices are not directly related to the user’s audiovisual experiences. Motivated by the fact that mobile devices are the network elements closest to the users, we explore the possibility of estimating user QoE by capitalizing on mobile terminal capabilities. For this purpose, we first collect over eighty thousand data records through a self-developed mobile application operating in the real world conditions with the support of a prominent Chinese wireless network operator (i.e., China Unicom). The collected data consist of 89 objective parameters concerning wireless video services and 4 types of subjective user scores. Then, we perform data preprocessing and feature selection based on Spearman correlation analyses. Finally, we establish two predictive models for QoE estimation based on the classification tree C4.5 algorithm and the gradient boosting decision tree (GBDT) algorithm, respectively. The experimental results demonstrate that the two decision tree-based models outperform other machine learning algorithms. Specifically, the prediction accuracy of the GBDT is approximately 70% for a five-level scale and approaches 90% for a more practical 3-level scale. Therefore, this study strongly demonstrates the feasibility of the user terminal-based approach for QoE prediction.

In this Letter, we report a back-end-of-line (BEOL), complementary metal–oxide–semiconductor (CMOS)-compatible Al0.64Sc0.36N-based ferroelectric diode that shows polarization-dependent hysteresis in its leakage currents. Our device comprises a metal/insulator/ferroelectric/metal structure (Pt/native oxide/Al0.64Sc0.36N/Pt) that is compatible with BEOL temperatures (≤ 350 °C) grown on top of a 4-in. silicon wafer. The device shows self-selective behavior as a diode with > 105 rectification ratio (for 5 V). It can suppress sneak currents without the need for additional access transistors or selectors. Furthermore, given the polarization-dependent leakage, the diode current–voltage sweeps are analogous to that of a memristor with an on/off ratio of ∼ 50 000 between low and high resistance states. Our devices also exhibit stable programed resistance states during DC cycling and a retention time longer than 1000 s at 300 K. These results demonstrate that this system has significant potential as a future high-performance post-CMOS compatible nonvolatile memory technology.

Solid-phase extraction (SPE) is a popular technique for environmental sample pretreatment. However, SPE usually requires complex sample pretreatment processes, which is time-consuming and inconvenient for real-time and on-site monitoring. Herein, a solvent-free, rapid, and user-friendly SPE device was developed by coating the polydimethylsiloxane (PDMS)/divinylbenzene (DVB) sorbent on the inner wall of a sample bottle. The extraction process and desorption process were both carried out in the bottle. The analytes trapped in the sorbent were thermally desorbed and simultaneously sucked out from the bottle by an air sampling tube equipped on field-portable GC-MS. Different to previous work, the sample pretreatment process didn’t require any complicated and time-consuming steps, such as centrifugation or filtration. The total analysis time for each sample was less than 25 min, which was feasible for rapid on-site detection, and thus avoided the losses and contamination of samples in conventional sample storage and transportation processes. Under optimal conditions, the proposed SPE method exhibited wide linear ranges, low detection limits (0.010–0.036 μg L−1, which were much lower than the maximum levels restricted by the US Environmental Protection Agency and the Chinese GB3838-2002 standard), good intra-bottle repeatability (6.13–7.17%, n = 3) and satisfactory inter-bottle reproducibility (4.73–6.47%, n = 3). Finally, the method was successfully applied to the rapid detection of BTEX in the field. The recoveries of BTEX in spiked water samples ranged from 89.1% to 116.2%. This work presents a novel SPE approach for rapid on-site monitoring in water samples.

In response to the current information needs of higher vocational mathematics and cultural teaching, Hadoop framework and collaborative recommendation algorithms are used to apply these two technologies to the construction of a shared platform for higher vocational mathematics and cultural infiltration teaching. Then through experiment and comparison, let the same teacher conduct mathematics and cultural infiltration teaching in two different classes. The results show that by investigating higher vocational students’ interest in mathematics and their understanding of mathematics, the number of people interested in vocational mathematics classes increased by 14.6%, and the number of people interested in control classes only increased by 10%. At the same time, in the assessment of mathematics culture penetration knowledge points, the number of outstanding people in the experimental group was significantly more than that in the control group.

Improvements are proposed in this paper to overcome the drawbacks of traditional fuzzy enhancement algorithms. Tanh operator is used as membership function, and fuzzy enhancement function are made up of simple power functions, and the image is divided into two regions by adaptive segmentation method, one is high grey region, the other is low grey region, pixels in one region are enhanced, and pixels in the other region are reduced. Simulation results show that this algorithm has good ability to increase image’s contrast, and it is a simple and efficient way to enhance blur edges.

Activities of Daily Living Scale (ADLs) is widely used to evaluate living abilities of the patients and the elderly. Most of the currently proposed approaches for tracking indicators of ADLs are human-centric. Considering the privacy concerns of the human-centric approaches, a new thing-centric sensing system, named TaRad, for detecting some indicators of ADLs (i.e. using fridge, making a phone call), through identifying vibration of objects when a person interacts with objects. It consists of action transceivers (named ViNode), smart phones and a server. By taking into account the limited computation resource of the action transceiver, and the drift and accuracy issues of the cheap sensor, a method of extracting features from the vibration signal, named ViFE, along with a light-weight activity recognition method, named ViAR, have been implemented in ViNode. Besides, an operator recognition method, named ViOR, has been proposed to recognize the acting person who generates vibration of action transceiver, when two or more people exist simultaneously within an area. Experimental results verify the performance of TaRad with different persons, in terms of the sensitivity to correctly detect the activities, and probability to successfully recognize the operators of the activities.

In this work, a novel series of morpholinyl dendrimer phthalocyanines were synthesized. Their structures were characterized by 1H NMR, IR, elemental analysis, ESI-MS as well as MALDI-TOF MS. The photophysical properties of these phthalocyanines were studied by UV/Vis and fluorescence spectroscopic methods. The photophysical properties of these dendrimer phthalocyanines exhibited dependence on the number of morpholinyl groups and the central ion. The photoinduced intramolecular electron transfer from the morpholinyl groups to the phthalocyanine ring was evidenced by the remarkably quenched fluorescence intensity and shortened lifetime of the silicon phthalocyanine. This difference in photoinduced intramolecular electron transfer effect for axially and peripherally substituted morpholinyl dendrimer phthalocyanines was also studied. Besides, introduction of morpholinyl groups on the dendrimer structure could enhance water solubility as well as increase the singlet oxygen quantum yield.

Miniaturized sample pretreatment platforms have simplified analytical tasks in diverse disciplines. Herein, a novel pipet microextraction (PME) device is reported by making use of the photothermal property of a light-heatable sorbent (LHS) for the first time. Efficient and staining-free heating treatment of small volumes of liquids confined in the PME device is now enabled through light illumination. The light-induced heating treatment is capable of dramatically accelerating solvent elution rates, effectively unlocking bound toxin from its antibody, and rapidly quenching enzymatic activities, thus, provides PME with higher efficiencies and enables its new applications in antibody-intermediated sampling of targeted toxin from stained food surfaces and powders, as well as in accurate revelation of enzymatic reaction kinetics. This study offers a new perspective of designing efficient and versatile microextraction platforms and demonstrates their potential applications in different fields including public security, new drug development, and environmental protection.

In order to enhance the carrier injection ofMoS2 field effect transistors (FETs,) understanding the injection mechanism of metal MoS 2 contacts is essential. In this work, MoS 2 (FETs) with Ti and Sc electrodes were faUricated and characterized, respectively. The carrier injection mechanism was studied from the perspective of the tunneling models. With the narrower barrier width, the MoS 2 contact shows a different injection mechanism from that of MoS 2 , making Sc a promising improvement as MoS 2 FETs electrodes.

In this paper, the curing mechanism of TiO2 photocatalytic film on the ceramic surface is introduced, and the relationship between photocatalysis, hydrophilicity and self-cleaning properties of TiO2 ceramics is analyzed. Finally, the mechanism of antimicrobial properties of TiO2 ceramics and its relationship with temperature were analyzed.

A novel initiator system containing KMO4, HIO4, and H2SO4 for synthesizing grafting starch copolymers is reported. In this system, KMnO4 was used to oxidize the primary hydroxyl group to aldehyde group of glucose in the starch, and the formed aldehyde group reacted with Mn(4+), Mn(3+) to afford starch free radical. At the same time HIO4 perform as the oxidant to open the C2C3 bond of glucose ring in starch to form two more aldehyde groups, and then two more free radicals are generated. As a result one glucose unit could provide ultimately three active sites for starch grafting reaction. Graft copolymers with a higher grafting ratio and grafting efficiency could be obtained by using the composite initiation system than the KMnO4/H2SO4 initiation system. The grafting of polyacrylamide onto the corn starch backbone was confirmed by viscometry, elemental analysis, infrared spectroscopy, nuclear magnetic resonance, X-ray diffraction and scanning electron microscopy.

The Asian hive bee Apis cerana has similar queen mandibular pheromones (QMP) to the Western honey bee Apismellifera. However the effects of individual QMP components have never been tested to determine their effects on the reproductive physiology of A. cerana workers. We fed one queen equivalent of each of the major components of A. cerana QMP to groups of c.a. 500 day-old, caged, workers twice a day until the workers were 10 days old. Half of the cages were also provided with 10% royal jelly in the food. Workers were sampled each day and dissected to determine the number of ovarioles and the degree of ovary activation (egg development). In cages treated with 9-carbon fatty acids ovary activation was minimal, whereas the 10-carbon acids suppressed ovary activation very little. Royal jelly enhanced ovary activation, especially in cages treated with 10-carbon acids. The number of ovarioles declined with bee age, but the rate of decline was slowed by the 9-carbon acids in particular. The results show conservation of the composition and function of QMP between A. cerana and A. mellifera and support the hypothesis that QMP is an honest signal of queen fecundity rather than a chemical castrator of workers.

Solid-phase microextraction (SPME) coupled with liquid chromatograph (LC) is widely used to detect polar and ionic organic compounds, including various pharmaceuticals and endogenous bioactive compounds. In this study, a small-sized insert tube for use in the commercial autosampler vial was designed for eluting the extracted analytes from SPME fibers for LC analysis. By using this custom-made insert tube as an alternative to the commercial insert tube, the volume of the elution solvent was reduced by four-fifths. Even though smaller fractions of the analytes were eluted from the fiber coatings, the analyte concentrations in the elution solutions were substantially increased by using the custom-made insert tube. Therefore, larger amounts of the analytes could be injected to LC and higher signal-to-noise ratios could be achieved, even at smaller injection volumes. Since the elution in the custom-made insert tube was nonexhaustive, four strategies were developed to figure out the extracted amounts in the fiber coatings. In combination with the sampling-rate calibration method, these strategies were successfully used to determine the concentrations of fluoxetine in living tilapias. This study provides a simple but effect way for improving the analytical sensitivity when coupling SPME with LC.

In this paper, the impact of gate voltage on the electron injection in a recently reported tunneling contact IGZO TFT has been studied. The dependence of the injection current on the temperature indicates thermionic emission dominates at small gate bias, while tunneling begins to contribute at large gate bias. The Schottky-barrier height at the metal/graphene/IGZO interface has been extracted, which is consistent with that obtained from previous photocurrent characterizations. The extracted barrier height implies the simplified contact physics and the applicability of the band alignment theory at the graphene inserted metal/IGZO interface.

In the social insects, ovary state (the presence or absence of mature oocytes) and ovary size (the number of ovarioles) are often used as proxies for the reproductive capacity of an individual worker. Ovary size is assumed to be fixed post-eclosion whereas ovary state is demonstrably plastic post-eclosion. Here, we show that in fact ovary size declines as honeybee workers age. This finding is robust across two honeybee species: Apis mellifera and A. cerana . The ovariole loss is likely to be due to the regression of particular ovarioles via programmed cell death. We also provide further support for the observation that honeybee workers with activated ovaries (mature oocytes present) most commonly have five ovarioles rather than a greater or smaller number. This result suggests that workers with more than five ovarioles are unable to physiologically support more than five activated ovarioles and that workers with fewer than five ovarioles are below a threshold necessary for ovary activation. As a worker's ovariole number declines with age, studies on worker ovariole number need to take this plasticity into account.

Sesuvium portulacastrum, a promising facultative halophyte species, has a remarkable ability to survival at severe salt of ~1000 mM NaCl. However, genes encoding proteins involved in the process of salt tolerance in S. portulacastrum are limited. In this study, suppression subtractive hybridization together with reverse northern blot analysis and RT-PCR was used to identify up-regulated genes in roots after treatment with seawater for 2–24 h. We identified a total of 148 unigenes, and most of these genes were predominantly associated with ‘signal transduction and transcription’, ‘stress/defense response’, ‘transport’ and ‘metabolism’. Comparative analysis between physiological response and differentially expressed genes highlighted that sodium (Na+) transport, compartmentation, reactive oxygen species (ROS) scavenging, and sugar-metabolizing regulation play important roles in salt tolerance of S. portulacastrum, whereas inhibition of root elongation induced by high salinity may be related to lignin deposition and disruption of calcium homeostasis.

Most models of animal choice behaviour assume that desirable but unavailable options, such as a high quality, but inhabited nest sites, do not influence an individual's preferences for the remaining options. However, experiments suggest that in mammals, the mere presence of such 'phantom' alternatives can alter, and even reverse, an individual's preferences for other items in a choice set. Phantom alternatives may be widespread in nature, as they occur whenever a resource is visible, but unavailable at the time of choice. They are particularly relevant for nectar-foraging animals, where previously rewarding flowers may sometimes be empty. Here, we investigate the effect of phantom alternatives on feeder preferences in the eastern honeybee, Apis cerana. First, we tested the effects of unattractive and attractive phantom alternatives by presenting individual bees with either a binary choice set containing two feeders that differed strongly in two qualities, but were equally preferred overall ('option 1' and 'option 2'), or a ternary choice set containing option 1, option 2 and one of two phantom types (unattractive and attractive). Secondly, we determined whether phantoms increase (similarity effect) or decrease (dissimilarity effect) preference for phantom-similar choices. In binary trials, bees had no significant preference for option 1 or option 2. However, after encountering an attractive phantom alternative, individual bees preferred option 2. The unattractive phantom did not influence bee preferences. Phantoms consistently changed individual bee preferences in favour of the phantom-similar choice. This means that the presence of an attractive food source, even if it is unavailable, can influence preference relationships between remaining items in the choice set. Our findings highlight the importance of considering the potential for phantom effects when studying the foraging behaviour of animals. Our results are particularly relevant for nectarivores, where empty but previously rewarding flowers are a common occurrence. Since an increase in pollinator visits can result in higher seed set, our results open up the possibility that by shifting pollinator preferences, empty flowers could have otherwise-unpredicted influences on community composition, plant-pollinator interactions and pollinator behaviour.

Objective With increasing expectations of a 5-year survival rate among cancer patients, there is growing interest in patient-reported outcome (PRO) measures, particularly measures of health-related quality of life (HRQOL) in cancer practice. The purpose of this review was to explore the existing interventions for patients coping with cancer in terms of intervention type, PRO measurements and outcomes; and to identify directions for future research. Methods Systematic review of randomised clinical trials. A systematic search of four databases was conducted to identify articles published in English or Chinese from January 2000 to July 2013. Studies were located using an electronic search, a manual search and an author search. Results A total of 34 articles corresponding to 33 original studies were identified and included in this review. These interventions were classified under four broad categories according to their approaches: psycho-education (15), case management (13), exercise (4) and feedback of PRO (1). The PRO measures covered different types of PRO measures, including HRQOL, functional status, symptom status, overall well-being and satisfaction with care. Positive outcomes of more than 70% (24) out of these interventions were reported. Conclusions These findings highlight the significant outcomes of cancer patient interventions that applied PRO measures to evaluate their outcomes. A theory-driven and careful design of the programme should be considered in the whole process of developing, delivering and assessing the programmes. Collaboration among patients, clinicians, researchers and policy makers is crucial to ensure the development of effective and accessible interventions targeting improving cancer survivors' HRQOL. Copyright © 2014 John Wiley & Sons, Ltd.

A cross-sectional study among a convenience sample of nurses in China was conducted to understand the factors affecting Chinese nurses’ willingness to report to work in a disaster. A total of 946 questionnaires were collected. Nearly 90 percent of nurses regarded disaster self-help information, an evacuation plan, and contingency measures a must in preparing for disaster care. Many nurses indicated willingness to work during a disaster that may threaten the safety of their family members than when there is a life-threatening infectious disease outbreak (83.6 and 69.6 percent, p = 0.000). Nurses with longer years of clinical experience were more willing to work in both situations (p = 0.014 and 0.000). Fear of contracting an infectious disease and spreading it to family members was a major factor for nurses’ unwillingness to report to work. Hospital administrators should understand their workforce’s willingness in reporting to work and provide appropriate disaster training and support to maximize workforce in a disaster.

In this manuscript, a series of catalyst SG n -[V V O 2 -PAMAM-MSA] (SG=silica gel, PAMAM=polyamidoamine, MSA=5-methyl salicylaldehyde, n =0, 1, 2, 3) was prepared and their structures were fully characterized by Fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and inductive coupled plasma emission spectrometer (ICP) etc . XPS revealed that the metal V and SG n -PAMAM-MSA combined more closely after the formation of Schiff base derivatives. Their catalytic activities for oxidation of dibenzothiophene were evaluated using tert -butyl hydroperoxide as oxidant. The results showed that the catalyst SG 2.0 -[V V O 2 -PAMAM-MSA] presented good catalytic activity and recycling time. Meanwhile, the optimal condition for the catalytic oxidation of SG 2.0 -[V V O 2 -PAMAM-MSA] was also investigated, which showed that when the oxidation temperature was 90 °C, time was 60 min, the O/S was 3U1, and the mass content of catalyst was 1%, the rate of desulfurization could reach 85.2%. Moreover, the catalyst can be recycled several times without significant decline in catalytic activity.

In the social insects, ovary state (the presence or absence of mature oocytes) and ovary size (the number of ovarioles) are often used as proxies for the reproductive capacity of an individual worker. Ovary size is assumed to be fixed post-eclosion whereas ovary state is demonstrably plastic post-eclosion. Here, we show that in fact ovary size declines as honeybee workers age. This finding is robust across two honeybee species: Apis mellifera and A. cerana. The ovariole loss is likely to be due to the regression of particular ovarioles via programmed cell death. We also provide further support for the observation that honeybee workers with activated ovaries (mature oocytes present) most commonly have five ovarioles rather than a greater or smaller number. This result suggests that workers with more than five ovarioles are unable to physiologically support more than five activated ovarioles and that workers with fewer than five ovarioles are below a threshold necessary for ovary activation. As a worker's ovariole number declines with age, studies on worker ovariole number need to take this plasticity into account.

In the social insects, ovary state (the presence or absence of mature oocytes) and ovary size (the number of ovarioles) are often used as proxies for the reproductive capacity of an individual worker. Ovary size is assumed to be fixed post-eclosion whereas ovary state is demonstrably plastic post-eclosion. Here, we show that in fact ovary size declines as honeybee workers age. This finding is robust across two honeybee species: Apis mellifera and A. cerana. The ovariole loss is likely to be due to the regression of particular ovarioles via programmed cell death. We also provide further support for the observation that honeybee workers with activated ovaries (mature oocytes present) most commonly have five ovarioles rather than a greater or smaller number. This result suggests that workers with more than five ovarioles are unable to physiologically support more than five activated ovarioles and that workers with fewer than five ovarioles are below a threshold necessary for ovary activation. As a worker's ovariole number declines with age, studies on worker ovariole number need to take this plasticity into account.

N-acyl-homoserine lactones (AHLs) are small diffusible molecules called autoinducers that mediate cell-to-cell communications. Enzymatic degradation of AHLs is a promising bio-control strategy known as quorum-quenching. To improve the quorum-quenching activity of a thermostable esterase Est816, which had been previously cloned, we have engineered the enzyme by random mutagenesis. One of the mutants M2 with double amino acid substitutions (A216V/K238N) showed 3-fold improvement on catalytic efficiency. Based on the crystal structure determined at 2.64 Å, rational design of M2 was conducted, giving rise to the mutant M3 (A216V/K238N/L122A). The kcat/KM value of the mutant M3 is 21.6-fold higher than that of Est816. Furthermore, activity assays demonstrated that M3 reached 99% conversion of 10-μM N-octanoyl-DL-homoserine lactone (C8-HSL) to N-octanoyl- DL-homoserine (C8-Hse) in 20 min, in contrast to the 8 h required by wild type Est816. The dramatic activity enhancement may be attributed to the increased hydrophobic interactions with the lactone ring by the mutation A216V, and the reduced steric clashes between the long side chain of L122 and the aliphatic tail of HSL by the mutation L122A, according to the crystal structure. This study sheds lights on the activity-structure relationship of AHL-lactonases, and may provide useful information in engineering AHL-degrading enzymes.

Alarm communication is a key adaptation that helps social groups resist predation and rally defenses. In Asia, the world’s largest hornet, Vespa mandarinia, and the smaller hornet, Vespa velutina, prey upon foragers and nests of the Asian honey bee, Apis cerana. We attacked foragers and colony nest entrances with these predators and provide the first evidence, in social insects, of an alarm signal that encodes graded danger and attack context. We show that, like Apis mellifera, A. cerana possesses a vibrational “stop signal,” which can be triggered by predator attacks upon foragers and inhibits waggle dancing. Large hornet attacks were more dangerous and resulted in higher bee mortality. Per attack at the colony level, large hornets elicited more stop signals than small hornets. Unexpectedly, stop signals elicited by large hornets (SS large hornet) had a significantly higher vibrational fundamental frequency than those elicited by small hornets (SS small hornet) and were more effective at inhibiting waggle dancing. Stop signals resulting from attacks upon the nest entrance (SS nest) were produced by foragers and guards and were significantly longer in pulse duration than stop signals elicited by attacks upon foragers (SS forager). Unlike SS forager, SS nest were targeted at dancing and non-dancing foragers and had the common effect, tuned to hornet threat level, of inhibiting bee departures from the safe interior of the nest. Meanwhile, nest defenders were triggered by the bee alarm pheromone and live hornet presence to heat-ball the hornet. In A. cerana, sophisticated recruitment communication that encodes food location, the waggle dance, is therefore matched with an inhibitory/alarm signal that encodes information about the context of danger and its threat level., Honey bees possess a vibrational alarm signal that encodes information about the level of danger at food and at the nest entrance., Author Summary Asian honey bees are attacked by formidable predators, giant hornets, at food sources and at their nests. We show that one species of honey bee, Apis cerana, has evolved an alarm signal, the stop signal, which warns nestmates of this danger. The stop signal consists of a brief vibrational pulse that encodes information about the danger level in signal frequency and the danger context in signal duration. Each danger level and danger context results in a distinctive signal. Receivers of these signals respond appropriately, stopping recruitment for the dangerous food location or remaining inside the safety of the nest, according to the encoded danger level and context. This is the first known example of such a complex alarm signal in an insect and demonstrates a new level of sophistication in bee communication.

In this manuscript, a novel probe RHBI based on the rhodamine-benzimidazole conjugate was designed and synthesized. RHBI showed an extreme selectivity for Fe(3+) over other metal ions such as Pb(2+), Ni(2+), Co(2+), Mn(2+), Zn(2+), Hg(2+), Cd(2+), Ag(+), Mg(2+), Ca(2+), Ba(2+), Na(+) and K(+) in acetonitrile. Upon the addition of 10 equiv. of Fe(3+), a 1098-fold fluorescence intensity enhancement was observed at the maximum emission wavelength of 582 nm. Both the Job's plot and ESI-MS showed that RHBI coordinated with Fe(3+) in a 1:1 stoichomitry and the calculated binding constant was 1.01 × 10(4) M(-1). The competition experiment for Fe(3+) ions mixed with other metal ions exhibited no obvious change except Cu(2+) that could induce a mild fluorescence quenching. Moreover, the fluorescence emission increased linearly with the Fe(3+) concentration in the range of 6 × 10(-6)-4 × 10(-5) M and the detection limit was 1.5 × 10(-8) M.

In this study, a novel tetrahedral molecule TPPY was successfully designed and synthesized. The self-assembly of TPPY with gold nanoparticles (Au NPs) in toluene has also been investigated. The aggregation morphologies of Au NPs can be controlled to produce different aggregate structures by changing the concentration of ligand TPPY.

Micro Pattern Gas Detector (MPGD) coupled to an optical imaging system is a good candidate for detecting polarization of X-ray, dark matter, neutron, etc. In this paper, a MicroMegas detector is designed for detecting the photoelectron track of X-ray, which working gas compose of an Ar+CF4 mixture and optical signal readout with an ICCD. The correlation of scintillation light intensity and electrical current is obtained in the varying strength of the electric field at avalanche region, and the position resolution is 385 mu m. The clear track images of the Am-241 alpha source and 5.9 KeV X-ray are obtained, and the X-ray imaging is achieved in the experiment.

The aim of this study was to investigate the effect of cigarette smoking on seminal plasma zinc levels and sperm parameters, and to examine the role of seminal plasma zinc. Semen samples from 79 non-smokers and 68 smokers were obtained. There was a significant decrease in seminal plasma zinc in smokers and a clear correlation between seminal plasma zinc levels and the extent of smoking. Sperm parameters (concentration, motility and morphology) among smokers were significantly lower in comparison to non-smokers. These parameters were also significantly decreased among smokers with abnormal zinc levels, while there was no significant difference between non-smokers with normal zinc and non-smokers with abnormal zinc levels. As previous studies have shown that seminal plasma zinc is associated with a decrease of anti-oxidant defences, seminal plasma zinc could be a contributor to the effects of cigarette smoking on sperm parameters. In conclusion, cigarette smoking can affect sperm parameters and this study may help towards providing a mechanistic explanation.

Animals may adjust their behavior according to their perception of risk. Here we show that free-flying honey bee (Apis cerana) foragers mitigate the risk of starvation in the field when foraging on a food source that offers variable rewards by carrying more ‘fuel’ food on their outward journey. We trained foragers to a feeder located 1.2 km from each of four colonies. On average foragers carried 12.7% greater volume of fuel, equivalent to 30.2% more glucose when foraging on a variable source (a random sequence of 0.5, 1.5 and 2.5 M sucrose solution, average sucrose content 1.5 M) than when forging on a consistent source (constant 1.5 M sucrose solution). Our findings complement an earlier study that showed that foragers decrease their fuel load as they become more familiar with a foraging place. We suggest that honey bee foragers are risk sensitive and carry more fuel to minimize the risk of starvation in the field when a foraging trip is perceived as being risky, either because the forager is unfamiliar with the foraging site, or because the forage available at a familiar site offers variable rewards.

Xenobiotics such as the neonicotinoid pesticide, imidacloprid, are used globally, but their effects on native bee species are poorly understood. We studied the effects of sublethal doses of imidacloprid on olfactory learning in the native honey bee species, Apis cerana, an important pollinator of agricultural and native plants throughout Asia. We provide the first evidence that imidacloprid can impair learning in A. cerana workers exposed as adults or as larvae. Adults that ingested a single imidacloprid dose as low as 0.1 ng/bee had significantly reduced olfactory learning acquisition, which was 1.6-fold higher in control bees. Longer-term learning (1-17 h after the last learning trial) was also impaired. Bees exposed as larvae to a total dose of 0.24 ng/bee did not have reduced survival to adulthood. However, these larval-treated bees had significantly impaired olfactory learning when tested as adults: control bees exhibited up to 4.8-fold better short-term learning acquisition, though longer-term learning was not affected. Thus, sublethal cognitive deficits elicited by neonicotinoids on a broad range of native bee species deserve further study.

If a honey bee (Apis spp.) colony becomes queenless, about 1/3 of young workers activate their ovaries and produce haploid male-producing eggs. In doing so queenless workers maximize their inclusive fitness because the normal option of vicarious production of relatives via their queen’s eggs is no longer available. But if many workers are engaged in reproduction, how does a queenless colony continue to feed its brood and forage? Here we show that in the Asian hive bee Apis cerana hypopharyngeal gland (HPG) size is larger in queenless workers than in queenright workers and that bees undertaking brood-rearing tasks have larger HPG than same-aged bees that are foraging. In queenless colonies, workers with a smaller number of ovarioles are more likely to have activated ovaries. This reinforces the puzzling observation that a large number of ovarioles reduces reproductive success in queenless A. cerana. It further suggests that reproductive workers either avoid foraging or transition to foraging later in life than non-reproductive workers. Finally, our study also showed that ovary activation and larger-than-average numbers of ovarioles had no statistically detectable influence on foraging specialization for pollen or nectar.

The theme of this study is innovative, and its aim is ar. The result of the research is valuable for medical ofessionals, especially for professionals engaged in pain anagements. The paper prompted the Acute Pain Nurses communicate with their patients more. As a result, they n know patients’ real pain feeling instead of overtimate and overtreatment. However, I think there are me drawbacks in the paper. Now, I show them for study d discussion. Firstly, the results showed in abstract of the article: ost patients considered NRS 4–6 as ‘‘bearable’’ pain. hile the Acute Pain Nurses considered NRS of 5 and gher not to be bearable. But in the conclusion, the author rote: A risk of overtreatment might arise when health re providers rigidly follow guidelines that prescribe ong analgesics for pain scores above 3 or 4. I wonder hy health care providers don’t prescribe strong analges for pain scores above 5 instead of 3 or 4 since the Acute in Nurses considered NRS of 5 and higher not to be arable. I think the author should interpret it clearly. Secondly, I don’t know why the author only give the percentage of the patients scored an NRS > 4, while did not calculate the percentage of the patients scored an NRS > 3 in Fig. 1. I think he/she should figure out both data because he/she presented the NRS threshold for prescribing analgesics varies: some guideline chose an NRS cut-off > 4, 4, while some chose an NRS cut-off > 3 as the criterion for administering analgesics in the introduction on page66. Further more, the latter is a new one. Similarly, in the results (3.1), when the author presented the distribution of the NRS scores of actual pain at rest 24 h after the operation, he/she should also describe the percentage of the patients scored for NRS > 3, except for the percentage scored with NRS > 4. Thirdly, the author said in the study design of Methods: The current study was part of a large cluster-randomized study. But I think the study used the convenience R T I C L E I N F O

An Artificial Neural Network (ANN) model of molten pool depth for Gas Metal Arc Welding process on plate with single-V groove and its intelligent control method are proposed in this paper. That how to select welding parameters as ANN models' input is mainly discussed, and fuzzy theory is used for molten pool depth control. The effectiveness of the proposed methods is demonstrated by the real experiments.

According to the characteristics that the paper currency image has low resolution and it is vulnerable to noise affect, the methods of paper serial number region extraction and segmentation are discussed, and multi-level 2DPCA algorithm is used for serial number recognition. Experiment results show that the methods proposed in this paper have the advantages of fast speed, high recognition accuracy and good anti-interference ability.

Introduced the present status of chain boiler efficiency is low, the system analysis of the chain boiler optimization and upgrading of technology, for the whole progress of chain boiler to provide some ideas and reference.

Background: Recent research has emphasized the importance of coping. There is virtually nothing known about coping strategies and their relationship with self-esteem, individual and environmental factors among Chinese female nursing students. This study was to identify different coping strategies, the relationship between coping and self-esteem and influencing individual factors among Chinese female students in different years of nursing school. Method: The study used a cross-sectional design. A representative sample composed of 686 female nursing students aged 14 years or older was surveyed in December 2010 using the Simplified Coping Styles Questionnaire, the Self-Esteem Scale and the Personal Data Form for assessment. Results: Nursing students more often used positive rather than negative coping styles ( P ＜0.001). There was significant difference in the positive coping between nursing students in different years of school ( P =0.018). The positive coping style was significantly correlated to a higher level of self-esteem, good interpersonal relationships, enough free time for study alone, a sense of self-fulfillment and satisfaction, adaptation to new study methods, close friendships, help-seeking behavior of an individual, and physical health in the past year ( P ＜0.05). The negative coping style was significantly associated with problems in romantic relationship, relationship with parents, worry about examinations and job assignment after graduation, feeling misunderstood, and frequent surfing on the internet ( P ＜0.05). Conclusion: There were different coping strategies and the important relationship between self-esteem, individual and environmental factors and coping strategies among Chinese female nursing students in different years of school. The teaching strategies that promote the self-esteem and pay more attention to students’ individual and environmental factors will be useful for helping nursing students develop effective coping styles.

SO2 measurements made in recent years at sites in Beijing and its surrounding areas are performed to study the variations and trends of surface SO2 at different types of sites in Northern China. The overall average concentrations of SO2 are (16.8 +/- 13.1) ppb, (14.8 +/- 9.4) ppb, and (7.5 +/- 4.0) ppb at China Meteorological Administration (CMA, Beijing urban area), Gucheng (GCH, relatively polluted rural area, 110 km to the southwest of Beijing urban area), and Shangdianzi (SDZ, clean background area, 100 km to the northeast of Beijing urban area), respectively. The SO2 levels in winter (heating season) are 4-6 folds higher than those in summer. There are highly significant correlations among the daily means of SO2 at different sites, indicating regional characteristics of SO2 pollution. Diurnal patterns of surface SO2 at all sites have a common feature with a daytime peak, which is probably caused by the downward mixing and/or the advection transport of SO2-richer air over the North China Plain. The concentrations of SO2 at CMA and GCH show highly significant downward trends (-4.4 ppb/yr for CMA and -2.4 ppb/yr for GCH), while a less significant trend (-0.3 ppb/yr) is identified in the data from SDZ, reflecting the character of SDZ as a regional atmospheric background site in North China. The SO2 concentrations of all three sites show a significant decrease from period before to after the control measures for the 2008 Olympic Games, suggesting that the SO2 pollution control has long-term effectiveness and benefits. In the post-Olympics period, the mean concentrations of SO2 at CMA, GCH, and SDZ are (14.3 +/- 11.0) ppb, (12.1 +/- 7.7) ppb, and (7.5 +/- 4.0) ppb, respectively, with reductions of 26%, 36%, and 13%, respectively, compared to the levels before. Detailed analysis shows that the differences of temperature, relative humidity, wind speed, and wind direction were not the dominant factors for the significant differences of SO2 between the pre-Olympics and post-Olympics periods. By extracting the data being more representative of local or regional characteristics, a reduction of up to 40% for SO2 in polluted areas and a reduction of 20% for regional SO2 are obtained for the effect of control measures implemented for the Olympic Games.